description
stringlengths 2.98k
3.35M
| abstract
stringlengths 94
10.6k
| cpc
int64 0
8
|
|---|---|---|
TECHNICAL FIELD
[0001] The present disclosure generally relates to vehicle infotainment systems, and more particularly, to systems and methods of providing radio station genre categorization features.
BACKGROUND
[0002] U.S. Pat. No. 7,403,755 generally discloses a monitoring receiver that accepts program preferences from an operator. When active, the receiver automatically monitors alternate frequencies for programming that matches the program preferences, alerts the operator when a match is found, and may switch to a preferred program.
[0003] U.S. Patent Publication No. 2006/0059535 generally discloses a receiver such as in an automobile and/or wireless communication device that is configured for a method of playing of live and recorded multimedia content. A desired genre of content is first defined. Both recorded and live content of that desired genre is identified and assembled into a playlist. Live content that is near a beginning of its being played can be rotated to a top of the playlist. In this way, live content, which a user may not have heard is given a priority of recorded content of the user. Since a start time of live content typically will not coincide with an end time of recorded content being played, the receiver can fade-in and fade-out to a the live content or buffer it for delayed play.
[0004] U.S. Patent Publication No. 2011/0028128 generally discloses an accessory device, such as a mobile telematics unit, that captures tags for user desired media content items from a content broadcast, such as a digital radio broadcast or television broadcast. Each tag provides one or more parameters for identification of a song or other audio selection. The accessory device sends each tag over a mobile communications network air interface, with an identifier of an account of a mobile communications network subscriber. A server receives such tag transmissions and compiles a list of one or more tags directly from the accessory device, for the subscriber on the identified mobile service account. In some situations, the server generates a playlist from the stored list of tags and communicates at least a portion of the playlist to a personal media device, upon access by the personal media device to the subscriber's account.
SUMMARY
[0005] In a first illustrative embodiment, a computer-implemented method includes receiving a request from a user to locate a radio station similar to a radio station currently providing content in a predefined genre to a radio receiver; accessing stored genre information compiled from a radio station scan to locate a second radio station providing content in the genre; and tuning the radio receiver to the second radio station.
[0006] In a second illustrative embodiment, a system includes at least one controller configured to receive a request from a user to locate a radio station similar to a radio station currently providing content in a predefined genre to a radio receiver; access stored genre information compiled from a radio station scan to locate a second radio station providing content in the genre; and tune the radio receiver to the second radio station.
[0007] In a third illustrative embodiment, a non-transitory computer readable medium includes instructions configured to cause at least one controller to receive a request from a user to locate a radio station similar to a radio station currently providing content in a predefined genre to a radio receiver; access stored genre information compiled from a radio station scan to locate a second radio station providing content in the genre; and tune the radio receiver to the second radio station.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an exemplary block topology of a vehicle infotainment system implementing a user-interactive vehicle information display system;
[0009] FIG. 2 is an exemplary block topology of an example system for integrating one or more nomadic devices with an infotainment system;
[0010] FIG. 3A illustrates an exemplary user interface for selection of a genre of radio station;
[0011] FIG. 3B illustrates an exemplary user interface for selection of a radio station within a selected genre;
[0012] FIG. 3C illustrates an exemplary user interface of a radio application tuned to a radio station and including a find similar feature;
[0013] FIG. 4 illustrates an exemplary process for gathering radio genre information; and
[0014] FIG. 5 illustrates an exemplary process for selection of radio stations utilizing genre-related features.
DETAILED DESCRIPTION
[0015] Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the embodiments. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.
[0016] The embodiments of the present disclosure generally provide for a plurality of circuits or other electrical devices. All references to the circuits and other electrical devices and the functionality provided by each, are not intended to be limited to encompassing only what is illustrated and described herein. While particular labels may be assigned to the various circuits or other electrical devices disclosed, such labels are not intended to limit the scope of operation for the circuits and the other electrical devices. Such circuits and other electrical devices may be combined with each other and/or separated in any manner based on the particular type of electrical implementation that is desired. It is recognized that any circuit or other electrical device disclosed herein may include any number of microprocessors, integrated circuits, memory devices (e.g., FLASH, random access memory (RAM), read only memory (ROM), electrically programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), or other suitable variants thereof) and software which co-act with one another to perform operation(s) disclosed herein. In addition, any one or more of the electric devices may be configured to execute a computer-program that is embodied in a non-transitory computer readable medium that is programmed to perform any number of the functions as disclosed.
[0017] A user may not know what content is being provided by an radio station until the user tunes a radio receiver to that station. Moreover, once the radio receiver is tuned to a station, it may be difficult for the user to determine more generally what genre of content is typically provided by that station.
[0018] Radio data system (RDS) is a communications protocol standard for embedding small amounts of digital information in conventional FM radio broadcasts, and standardizes several types of information transmitted, including time, station identification and program information. A vehicle system may scan the FM frequency band to retrieve RDS data transmitted by local FM stations. Based on the received RDS data, the vehicle system may compile a listing of genres and stations within each genre. This information may be maintained by the vehicle system, and utilized in the radio user interface to support additional genre-related station browsing features.
[0019] As one example, the vehicle user interface may include a feature to allow for browsing of radio stations according to genre. The user interface may provide a listing of genres based on the RDS data for a user to select. When selected, the user interface may further provide a listing of the stations within the selected genre for the user to select. As another example, the user interface may provide a find similar user interface element to allow a user to tune to another radio station indicated as being within the same genre as the currently tuned radio station.
[0020] FIG. 1 illustrates an example block topology for a vehicle based computing system 1 (VCS) for a vehicle 31 . An example of such a vehicle-based computing system 1 is the SYNC system manufactured by THE FORD MOTOR COMPANY. A vehicle enabled with a vehicle-based computing system may contain a visual front end interface 4 located in the vehicle. The user may also be able to interact with the interface if it is provided, for example, with a touch sensitive screen. In another illustrative embodiment, the interaction occurs through, button presses, spoken dialog system with automatic speech recognition and speech synthesis.
[0021] In the illustrative embodiment 1 shown in FIG. 1 , a processor 3 controls at least some portion of the operation of the vehicle-based computing system. Provided within the vehicle, the processor allows onboard processing of commands and routines. Further, the processor is connected to both non-persistent 5 and persistent storage 7 . In this illustrative embodiment, the non-persistent storage is random access memory (RAM) and the persistent storage is a hard disk drive (HDD) or flash memory. In general, persistent (non-transitory) memory can include all forms of memory that maintain data when a computer or other device is powered down. These include, but are not limited to, HDDs, CDs, DVDs, magnetic tapes, solid state drives, portable USB drives and any other suitable form of persistent memory.
[0022] The processor is also provided with a number of different inputs allowing the user to interface with the processor. In this illustrative embodiment, a microphone 29 , an auxiliary input 25 (for input 33 ), a USB input 23 , a GPS input 24 , screen 4 , which may be a touchscreen display, and a BLUETOOTH input 15 are all provided. An input selector 51 is also provided, to allow a user to swap between various inputs. Input to both the microphone and the auxiliary connector is converted from analog to digital by a converter 27 before being passed to the processor. Although not shown, numerous of the vehicle components and auxiliary components in communication with the VCS may use a vehicle network (such as, but not limited to, a CAN bus) to pass data to and from the VCS (or components thereof).
[0023] Outputs to the system can include, but are not limited to, a visual display 4 and a speaker 13 or stereo system output. The speaker is connected to an amplifier 11 and receives its signal from the processor 3 through a digital-to-analog converter 9 . Output can also be made to a remote BLUETOOTH device such as PND 54 or a USB device such as vehicle navigation device 60 along the bi-directional data streams shown at 19 and 21 respectively.
[0024] In one illustrative embodiment, the system 1 uses the BLUETOOTH transceiver 15 to communicate 17 with a user's nomadic device 53 (e.g., cell phone, smart phone, PDA, or any other device having wireless remote network connectivity). The nomadic device can then be used to communicate 59 with a network 61 outside the vehicle 31 through, for example, communication 55 with a cellular tower 57 . In some embodiments, tower 57 may be a WiFi access point.
[0025] Exemplary communication between the nomadic device and the BLUETOOTH transceiver is represented by signal 14 .
[0026] Pairing a nomadic device 53 and the BLUETOOTH transceiver 15 can be instructed through a button 52 or similar input. Accordingly, the CPU is instructed that the onboard BLUETOOTH transceiver will be paired with a BLUETOOTH transceiver in a nomadic device.
[0027] Data may be communicated between CPU 3 and network 61 utilizing, for example, a data-plan, data over voice, or DTMF tones associated with nomadic device 53 . Alternatively, it may be desirable to include an onboard modem 63 having antenna 18 in order to communicate 16 data between CPU 3 and network 61 over the voice band. The nomadic device 53 can then be used to communicate 59 with a network 61 outside the vehicle 31 through, for example, communication 55 with a cellular tower 57 . In some embodiments, the modem 63 may establish communication 20 with the tower 57 for communicating with network 61 . As a non-limiting example, modem 63 may be a USB cellular modem and communication 20 may be cellular communication.
[0028] In one illustrative embodiment, the processor is provided with an operating system including an API to communicate with modem application software. The modem application software may access an embedded module or firmware on the BLUETOOTH transceiver to complete wireless communication with a remote BLUETOOTH transceiver (such as that found in a nomadic device). Bluetooth is a subset of the IEEE 802 PAN (personal area network) protocols. IEEE 802 LAN (local area network) protocols include WiFi and have considerable cross-functionality with IEEE 802 PAN. Both are suitable for wireless communication within a vehicle. Another communication means that can be used in this realm is free-space optical communication (such as IrDA) and non-standardized consumer IR protocols.
[0029] In another embodiment, nomadic device 53 includes a modem for voice band or broadband data communication. In the data-over-voice embodiment, a technique known as frequency division multiplexing may be implemented when the owner of the nomadic device can talk over the device while data is being transferred. At other times, when the owner is not using the device, the data transfer can use the whole bandwidth (300 Hz to 3.4 kHz in one example). While frequency division multiplexing may be common for analog cellular communication between the vehicle and the internet, and is still used, it has been largely replaced by hybrids of Code Domain Multiple Access (CDMA), Time Domain Multiple Access (TDMA), Space-Domain Multiple Access (SDMA) for digital cellular communication. These are all ITU IMT-2000 (3G) compliant standards and offer data rates up to 2 mbs for stationary or walking users and 385 kbs for users in a moving vehicle. 3G standards are now being replaced by IMT-Advanced (4G) which offers 100 mbs for users in a vehicle and 1 gbs for stationary users. If the user has a data-plan associated with the nomadic device, it is possible that the data-plan allows for broad-band transmission and the system could use a much wider bandwidth (speeding up data transfer). In still another embodiment, nomadic device 53 is replaced with a cellular communication device (not shown) that is installed to vehicle 31 . In yet another embodiment, the ND 53 may be a wireless local area network (LAN) device capable of communication over, for example (and without limitation), an 802.11g network (i.e., WiFi) or a WiMax network.
[0030] In one embodiment, incoming data can be passed through the nomadic device via a data-over-voice or data-plan, through the onboard BLUETOOTH transceiver and into the vehicle's internal processor 3 . In the case of certain temporary data, for example, the data can be stored on the HDD or other storage media 7 until such time as the data is no longer needed.
[0031] Additional sources that may interface with the vehicle include a personal navigation device 54 , having, for example, a USB connection 56 and/or an antenna 58 , a vehicle navigation device 60 having a USB 62 or other connection, an onboard GPS device 24 , or remote navigation system (not shown) having connectivity to network 61 . USB is one of a class of serial networking protocols. IEEE 1394 (FireWire™ (Apple), i.LINK™ (Sony), and Lynx™ (Texas Instruments)), EIA (Electronics Industry Association) serial protocols, IEEE 1284 (Centronics Port), S/PDIF (Sony/Philips Digital Interconnect Format) and USB-IF (USB Implementers Forum) form the backbone of the device-device serial standards. Most of the protocols can be implemented for either electrical or optical communication.
[0032] Further, the CPU could be in communication with a variety of other auxiliary devices 65 . These devices can be connected through a wireless 67 or wired 69 connection. Auxiliary device 65 may include, but are not limited to, personal media players, wireless health devices, portable computers, and the like.
[0033] Also, or alternatively, the CPU could be connected to a vehicle based wireless router 73 , using for example a WiFi (IEEE 803.11) 71 transceiver. This could allow the CPU to connect to remote networks in range of the local router 73 .
[0034] In addition to having exemplary processes executed by a vehicle computing system located in a vehicle, in certain embodiments, the exemplary processes may be executed by a computing system in communication with a vehicle computing system. Such a system may include, but is not limited to, a wireless device (e.g., and without limitation, a mobile phone) or a remote computing system (e.g., and without limitation, a server) connected through the wireless device. Collectively, such systems may be referred to as vehicle associated computing systems (VACS). In certain embodiments particular components of the VACS may perform particular portions of a process depending on the particular implementation of the system. By way of example and not limitation, if a process has a step of sending or receiving information with a paired wireless device, then it is likely that the wireless device is not performing the process, since the wireless device would not “send and receive” information with itself. One of ordinary skill in the art will understand when it is inappropriate to apply a particular VACS to a given solution. In all solutions, it is contemplated that at least the vehicle computing system (VCS) located within the vehicle itself is capable of performing the exemplary processes.
[0035] FIG. 2 is an exemplary block topology of a system for integrating one or more connected devices with the vehicle based computing system 1 (VCS). To facilitate the integration, the CPU 3 may include a device integration framework 101 configured to provide various services to the connected devices. These services may include transport routing of messages between the connected devices and the CPU 3 , global notification services to allow connected devices to provide alerts to the user, application launch and management facilities to allow for unified access to applications executed by the CPU 3 and those executed by the connected devices, and point of interest location and management services for various possible vehicle 31 destinations.
[0036] As mentioned above, the CPU 3 of the VCS 1 may be configured to interface with one or more nomadic devices 53 of various types. The nomadic device 53 may further include a device integration client component 103 to allow the nomadic device 53 to take advantage of the services provided by the device integration framework 101 . Applications executed by the nomadic device 53 may accordingly utilize the device integration client component 103 to interact with the CPU 3 via the device integration framework 101 . As one example, a music player application on the nomadic device 31 may interact with the CPU 3 to provide streaming music through the speaker 13 or stereo system output of the VCS 1 . As another example, a navigation application on the nomadic device 31 may interact with the CPU 3 to provide turn-by-turn directions for display on the screen 4 of the VCS 1 .
[0037] The multiport connector hub 102 may be used to interface between the CPU 3 and additional types of connected devices other than the nomadic devices 53 . The multiport connector hub 102 may communicate with the CPU 3 over various buses and protocols, such as via USB, and may further communicate with the connected devices using various other connection buses and protocols, such as Serial Peripheral Interface Bus (SPI), Inter-integrated circuit (I2C), and/or Universal Asynchronous Receiver/Transmitter (UART). The multiport connector hub 102 may further perform communication protocol translation and interworking services between the protocols used by the connected devices and the protocol used between the multiport connector hub 102 and the CPU 3 . The connected devices may include, as some non-limiting examples, a radar detector 104 , a global position receiver device 106 , and a storage device 108 .
[0038] A VCS 1 may include one or more receivers configured to receive audio content. For example, the VCS 1 may include an FM radio receiver configured to receive frequency-modulated radio transmissions from radio stations broadcasting within the frequency band of 87.5 to 108.0 MHz. In addition to receiving audio content, the VCS 1 may be further configured to receive metadata regarding the radio stations providing the audio content. For example, the VCS 1 may be configured to scan the FM frequency band to retrieve RDS data transmitted by the radio stations.
[0039] The metadata may include, for example, station identification (e.g., via the RDS data program identification (PI) or program service (PS) data elements) and genre information indicative of the types of audio content provided by the radio station (e.g., via the RDS data program type (PTY) data element). These genres may include, as some non-limiting examples: news, information, sports, talk, rock, classic rock, adult hits, soft rock, top 40, country, oldies, soft, nostalgia, jazz, classical, rhythm and blues, soft rhythm and blues, language, religion music, religious talk, personality, public, college, Spanish talk, Spanish music, hip hop, unassigned, weather, emergency test or emergency. The metadata may also include information regarding the specifics of the audio content currently being provided, such as the song, artist, or radio show currently being broadcast (e.g., via the RDS data radio text (RT) data element).
[0040] In some cases, a system may utilize a single radio receiver. In such cases, the metadata content may be received using the same receiver used to receive the audio content. In other cases, a system may include multiple receivers. As one possibility, the VCS 1 may include a first receiver to receive the audio content, and a second receiver to scan the available stations for genre information. The second receiver may be implemented, for example, as a module connected to the VCS 1 via the multiport connector hub 102 . As another possibility, the VCS 1 may utilize multiple receivers for metadata retrieval to increase the speed of the scanning of available stations (e.g., both an internal receiver not currently being used to receive audio content and also a receiver module connected via the hub 102 ).
[0041] Based on the received audio metadata data, the VCS 1 may compile a listing of genres and stations within each genre. Continuing to use RDS as an example, each station may be associated with a genre corresponding to the PTY code received during the FM frequency scan. The genre information compiled based on the station scan may be maintained by the VCS 1 .
[0042] The VCS 1 may determine whether to rescan the radio stations for updated metadata based on various triggers. As one possibility, the VCS 1 may be configured to initiate a station scan when radio functionality of the VCS 1 is invoked. As another possibility, the VCS 1 may be configured to initiate a station scan if there is no currently cached station metadata information, or if the currently cached station metadata information is older than a predetermined amount of time (e.g., 24 hours old, 30 days old, etc.). As yet a further possibility, the VCS 1 may be configured to maintain an indication of a geographic location of the vehicle 31 when the scan was last performed (e.g. using the GPS input 24 ), and may initiate a station scan if the vehicle has moved at least a threshold distance from the geographic location of when a scan was last performed (e.g., 25 miles, 50 miles, etc.).
[0043] Using the genre information, the VCS 1 may be configured to provide additional genre-related station browsing features in the radio user interface. These additional features may include a user interface for browsing radio stations by genre, as well as a user interface for finding a radio station playing content in the same genre as the radio station to which the VCS 1 is currently tuned.
[0044] FIG. 3A illustrates an exemplary user interface 300 -A for selection of a genre of radio station. The user interface 300 -A may be displayed, for example, on a display screen 4 of the VCS 1 . Based on the compiled genre information, the user interface 300 -A may be configured to present a listing of genre user interface elements 302 that correspond to the available genres of radio station. The user interface 300 -A may also include or update a label 304 to indicate to the user that the current user interface 300 -A facilities selection of a genre of radio station. In the exemplary user interface, the genre user interface elements 302 include a sports genre element 302 -A, an adult hits genre element 302 -B, a top 40 genre element 302 -C, a country genre element 302 -D, a rhythm and blues genre element 302 -E, a public radio genre element 302 -F, an emergency information genre element 302 -G, and an unknown genre element 302 -H (e.g., for those stations for which a genre was specified as unknown, was not specified, or otherwise could not be identified). While the user interface 300 -A includes eight genre elements 302 -A through genre element 302 -H, it should be noted that based on the compiled genre information, more, fewer, or different genre elements 302 may be included in the user interface 300 -A.
[0045] The genre user interface elements 302 may be selectable by a user to allow the user to choose from stations in the selected radio station genre. For example, selection of the sports genre element 302 -A may cause the VCS 1 to present a listing of available sports stations, and selection of the rhythm and blues genre element 302 -E may cause the VCS 1 to present a listing of available rhythm and blues stations.
[0046] As illustrated, only genre user interface elements 302 for which stations exist may be appear in the user interface 300 -A. In other cases, the user interface 300 -A may include genre user interface elements 302 for various possible genres, regardless of whether any radio stations are associated with the genre. In such cases, the genre user interface elements 302 corresponding to genres in which no stations are present may be included in the user interface 300 -A but in a disabled form, such that they may not cause the VCS 1 to present a listing of available stations within the genre. Or, upon selection the user interface 300 -A may provide a notification message indicating that no stations are presently available within the selected genre.
[0047] FIG. 3B illustrates an exemplary user interface 300 -B for selection of a radio station within a selected genre. The user interface 300 -B may be configured to present a listing of radio station user interface elements 306 that are included in the genre corresponding to a genre element 302 selected from the user interface 300 -A. The user interface 300 -B may also be configured to include or update a label 304 in the user interface 300 -B to be indicative of the selected genre.
[0048] For example, the user interface 300 -B may be provided upon receipt of user selection of the rhythm and blues genre element 302 -E from the user interface 300 -A. The VCS 1 may identify based on the compiled genre information that the stations 97.9 FM, 103.5 FM, and 104.3 FM fall within the rhythm and blues genre. Accordingly, the VCA 1 may include a radio station user interface element 306 -A corresponding to 97.9 FM, a radio station user interface element 306 -B corresponding to 103.5 FM, and a radio station user interface element 306 -C corresponding to 104.3 FM.
[0049] The radio station user interface elements 306 may be selectable by a user to allow the user to choose to listen to the selected radio station. For example, selection of the radio station user interface element 306 -A may cause the VCS 1 to tune the radio to 97.9 FM, and selection of the radio station user interface element 306 -C may cause the VCS 1 to tune the radio to 104.3 FM.
[0050] FIG. 3C illustrates an exemplary user interface 300 -C of a radio application tuned to a radio station and including a find similar feature 310 . The user interface 300 -C may be configured to present details of the currently-tuned radio station in one or more radio information interface elements 308 . The information included in the elements 308 may include, for example, an indication of the currently tuned radio station, information regarding the genre of the radio station, and information regarding the content presently being provided by the station such as song, artist, radio show, etc. (e.g., determined according to retrieved RDS data, as one example). The user interface 300 -C may also be configured to include or update a label 304 in the user interface 300 -C to indicate that the user interface 300 -C represents information regarding the currently tuned radio station.
[0051] The user interface 300 -C may be provided based on selection of a radio station user interface element 306 from the user interface 300 -B. For example, the user interface 300 -C may be provided upon receipt of user selection of the radio station user interface element 306 -C associated with 104.3 FM from the user interface 300 -B.
[0052] It should also be noted that the user interface 300 -C may be displayed in situations other than resulting from user selection of the radio station user interface element 306 -C. For example, if only one radio station is included in a genre, then selection of a genre user interface element 302 form the user interface 300 -A for that genre may result in the VCS 1 providing the user interface 300 -C for that radio station, without requiring the user to select the only available choice from the user interface 300 -B.
[0053] The user interface 300 -C may be displayed based on other user interface flows as well. As some possibilities, the user interface 300 -C may be displayed in response to a user selecting a radio station preset, in response to the user seeking or scanning to the radio station, or in response to the user utilizing a direct tune feature to direct the radio to the radio station.
[0054] Moreover, the user interface 300 -C may also include a find similar user interface element 310 . The find similar user interface element 310 may be configured to allow a user to easily tune to another radio station in the same genre as the currently tuned radio station. Upon receipt of user selection of the find similar user interface element 310 , the VCS 1 may identify a similar station based on the compiled genre information, and may tune the radio to the identified similar radio station.
[0055] For example, as mentioned above with respect to the user interface 300 -B, in the illustrated example the genre information includes two other stations in the same genre as the currently tuned radio station (i.e., 97.9 FM and 104.3 FM are also in the rhythm and blues genre along with 104.3 FM). Thus, the VCS 1 may be tune the radio to either 97.9 FM or 104.3 FM. As one possibility, the VCS 1 may select the next station in frequency order. For instance, if the radio is tuned to 103.5 FM, then selecting the find similar user interface element 310 may tune the radio to 104.3 FM, selecting the find similar user interface element 310 again may tune the radio to 97.9 FM, and selecting the find similar user interface element 310 again may tune the radio back to 103.5 FM.
[0056] A user may accordingly use the find similar user interface element 310 to cycle through the available programming within a particular genre of music, without having to know which radio stations play content in what genre. Moreover, the user may be able to automatically browse content in an unfamiliar city, also without having to know which stations play what genres of content.
[0057] FIG. 4 illustrates an exemplary process for gathering radio genre information. As one possibility, the process 400 may be implemented using software code contained within the VCS 1 . In other embodiments, the process 400 may be implemented in other vehicle controllers, or distributed amongst multiple vehicle controllers.
[0058] At decision point 402 , the VCS 1 determines whether to capture updated genre information. For example, the VCS 1 may be configured to initiate a station scan when radio functionality of the VCS 1 is invoked, or when radio functionality requiring genre information is invoked. As another possibility, the VCS 1 may be configured to initiate a station scan if there is no currently cached station metadata information, or if the currently cached station metadata information is older than a predetermined amount of time (e.g., 24 hours old, 30 days old, etc.). As yet a further possibility, the VCS 1 may be configured to maintain an indication of a geographic location of the vehicle 31 when the scan was last performed, and may initiate a station scan if the vehicle has moved at least a threshold distance from the geographic location of when a scan was last performed (e.g., 25 miles, 50 miles, etc.). If the VCS 1 determines that updated genre information should be captures, control passes to block 404 . Otherwise, control remains at decision point 402 .
[0059] At block 404 , the VCS 1 performs a scan for genre information. For example, the VCS 1 may be configured to utilize one or more radio receivers to scan the FM frequency band to retrieve RDS data transmitted by the radio stations. The metadata may include, for example, station identification (e.g., via the RDS data program identification (PI) or program service (PS) data elements) and genre information indicative of the types of audio content provided by the radio station (e.g., via the RDS data program type (PTY) data element). These genres may include, as some non-limiting examples: news, information, sports, talk, rock, classic rock, adult huts, soft rock, top 40, country, oldies, soft, nostalgia, jazz, classical, rhythm and blues, soft rhythm and blues, language, religion music, religious talk, personality, public, college, Spanish talk, Spanish music, hip hop, unassigned, weather, emergency test or emergency. The metadata may also include information regarding the specifics of the audio content currently being provided, such as the song, artist, or radio show currently being broadcast (e.g., via the RDS data radio text (RT) data element).
[0060] At block 406 , the VCS 1 compiles the genre information. For example, based on the received audio metadata data, the VCS 1 may compile a listing of genres and stations within each genre. Continuing to use RDS as an example, each station may be associated with a genre corresponding to the PTY code received during the FM frequency scan.
[0061] At block 408 , the VCS 1 caches the compiled genre information. The compiled genre information may accordingly be maintained by the vehicle system, and utilized in the radio user interface to support additional genre-related station browsing features. Using the genre information, the VCS 1 may be configured to provide additional genre-related station browsing features in the radio user interface. These additional features may include, as some examples, a user interface for browsing radio stations by genre, as well as a user interface for finding a radio station playing content in the same genre as the radio station to which the VCS 1 is currently tuned. After block 408 , control passes to decision point 402 .
[0062] FIG. 5 illustrates an exemplary process for selection of radio stations utilizing genre-related features. As with the process 400 , the process 500 may be implemented using software code contained within the VCS 1 . In other embodiments, the process 500 may be implemented in other vehicle controllers, or distributed amongst multiple vehicle controllers.
[0063] At decision point 502 , the VCS 1 determines whether the user wishes to select a radio station by genre. For example, the user may select an element from a radio user interface 300 requesting to tune by genre. If the user wishes to select a radio station by genre, control passes to block 504 . Otherwise, control passes to block 514 .
[0064] At block 504 , the VCS 1 displays a listing of station genres. For example, the VCS 1 may display an exemplary user interface 300 -A for selection of a genre of radio station, such as the one discussed above with respect to FIG. 3A . The user interface 300 -A may be displayed, for example, on a display screen 4 of the VCS 1 . The user interface 300 -A may present, for example, a listing of genre user interface elements 302 that correspond to the available genres of radio station as determined based on the genre information, as well as a label 304 to indicate to the user that the current user interface 300 -A facilities selection of a genre of radio station.
[0065] At block 506 , the VCS 1 receives a genre selection from the user interface. For example, the genre user interface elements 302 of the user interface 300 -A may be selectable by a user, and the user may select one of the genre user interface elements 302 from the user interface 300 -A.
[0066] At block 508 , the VCS 1 displays stations in the selected genre. For example, the VCS 1 may display an exemplary user interface 300 -B for selection of a radio station within a selected genre, such as the one discussed above with respect to FIG. 3B . The user interface 300 -B may be configured to present a listing of radio station user interface elements 306 that correspond to a genre element 302 selected from the user interface 300 -A. The user interface 300 -B may also be configured to include or update a label 304 in the user interface 300 -B to be indicative of the selected genre.
[0067] At block 510 , the VCS 1 receives a station selection from the displayed stations. For example, the radio station user interface elements 306 of the user interface 300 -B may be selectable by a user, and the user may select one of the radio station user interface elements 306 from the user interface 300 -B.
[0068] At block 512 , the VCS 1 tunes to the selected station. For example, upon receipt of user selection of one of the radio station user interface element 306 from the user interface 300 -B, the VCS 1 may set a receiver of the VCS 1 to receive audio content from the selected radio station, and may provide the user interface 300 -C to indicate to the user that the selected station is now playing. After block 512 , control may pass to decision point 516 .
[0069] At block 514 , the VCS 1 receives a station selection through a mechanism other than via genre information. For example, the user may select a radio station preset, may utilize a seek or scan radio feature to browse to a station, or may utilizing a direct tune feature to directly enter a station frequency into the VCS 1 . After block 514 , control may pass to block 512 to tune to the selected station.
[0070] At decision point 516 , the VCS 1 determines whether the user requests the radio to tune to a similar station. For example, as discussed above with respect to FIG. 3C , the VCS 1 may include a find similar user interface element 310 in the user interface 300 -C to allow a user to easily tune to another radio station in the same genre as the currently tuned radio station. If the user selects the find similar user interface element 310 , control passes to block 518 . Otherwise, control passes to decision point 520 .
[0071] At block 518 , the VCS 1 tunes the radio to an identified similar radio station. For example, the VCS 1 may identify a similar station based on the compiled genre information. For example, based on the genre information, the VCS 1 may select another radio station in the same genre as the currently tuned radio station. After block 518 , control passes to block 512 to tune to the selected station.
[0072] At decision point 520 , the VCS 1 determines whether the user requests the radio to tune to another station. For example, user may select an element from a radio user interface 300 indicating that the user wishes to tune to another station. If the user requests to tune to another station, control passes to decision block 502 . Otherwise, control passes to decision point 516 .
[0073] Referring again to FIGS. 4-5 , the vehicle and its components illustrated in FIG. 1 and FIG. 2 are referenced throughout the discussion of the processes 400 and 500 to facilitate understanding of various aspects of the present disclosure. The processes 400 and 500 may be implemented through a computer algorithm, machine executable code, or software instructions programmed into a suitable programmable logic device(s) of the vehicle, such as the vehicle control module, the hybrid control module, another controller in communication with the vehicle computing system, or a combination thereof. Although the various steps shown in the process 500 and 600 appear to occur in a chronological sequence, at least some of the steps may occur in a different order, and some steps may be performed concurrently or not at all.
[0074] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes can include, but are not limited to cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and can be desirable for particular applications.
|
A computer-implemented method includes receiving a request from a user to locate a radio station similar to a radio station currently providing content in a predefined genre to a radio receiver; accessing stored genre information compiled from a radio station scan to locate a second radio station providing content in the genre; and tuning the radio receiver to the second radio station.
| 7
|
BACKGROUND OF THE INVENTION
[0001] The present invention is related to a managing computer connected to a network to which a plurality of computers are connected, for managing these computers. More specifically, the present invention is directed to a technique capable of managing administrate operations executed in the respective computers in a batch mode by the managing computer.
[0002] Managing computers for managing administrate operations are described in U.S. Pat. No. 5,169,655 entitled to Weng et al., and U.S. Pat. No. 5,642,508 entitled to Miyazawa. The administrate operations involve a job execution process; and a process executed when a specific event occurs.
[0003] In a large-scaled computer system where a plurality of administrate operations may be combined with each other to be executed, since definitions as to the respective administrate operations must be separately performed and also execution results must be independently confirmed, the management for the total computer system can be hardly carried out.
[0004] More specifically, in a large-scaled computer system, there are certain possibilities that a plurality of administrate operations which are executed in combination with each other are executed over a plurality of computers. Under such a circumstance, in order to realize a total management as a computer system, processed contents as to all of administrate operations may be preferably defined and execution results thereof may be preferably confirmed by using a single computer, namely a single managing computer.
[0005] However, in the case that the definitions of the processed contents and the confirmations of the execution results as to all of the administrate operations may be performed by one managing computer, since the managing computer must be communicated with the respective computers, a specific care should be paid to the network traffics.
SUMMARY OF THE INVENTION
[0006] Therefore, an object of the present invention is to realize such a computer system to which a plurality of computers are connected. In this computer system, a managing computer for managing these computers can manage administrate operations executed in the respective computers are managed in a batch mode.
[0007] Furthermore, another object of the present invention is to avoid such that an extra load is given to a network connecting a managing computer group, which is caused by an operation managing computer.
[0008] To achieve the above-described object, there is provided a managing computer comprising:
[0009] an acquiring device for acquiring log information and event information from any of plural computers connected via a network to each other, said log information indicating as to whether or not an execution of an operation process is carried out under normal condition, and said event information indicating concisely as to whether or not an execution of an operation process is carried out under normal condition;
[0010] a data controller for storing into a database, operation definition information used to define a schedule of process operations executed in said plural computers in relation to said log information and said event information acquired by said acquiring device; and
[0011] a display device for displaying said operation definition information in relation to event information related to a process operation defined by said operation definition information with reference to the information stored in said database. It is possible to provide a managing computer, according to a first aspect of the present invention, is featured by such a managing computer connected to a network to which a plurality of computers are connected, for managing these computers, comprising:
[0012] acquisition means for acquiring log information indicative of an execution result of an administrate operation executed in each of the computers and also event information indicative of an event occurred in an execution stage of the administrate operation from each of said computers;
[0013] storage means for into a database, operation definition information in which a schedule of the administrate operations executed in the respective computers, and also the log information and the event information acquired by said acquisition means; and
[0014] display means for displaying the operation definition information related to the respective computers in relation to log information and event information of an administrate operation defined by the operation definition information with reference to the information stored into the database by the storage means.
[0015] Also, a managing computer, according to a second aspect of the present invention, is featured by such a managing computer connected to a network to which a plurality of computers are connected, for managing these computers, comprising:
[0016] acquisition means for acquiring log information indicative of an execution result of an administrate operation executed in each of the computers and also event information indicative of an event occurred in an execution stage of the administrate operation from each of said computers;
[0017] storage means for into a database, operation definition information in which a schedule of the administrate operations executed in the respective computers, and also the log information and the event information acquired by said acquisition means; and
[0018] display means for displaying both a region for describing a list-of administrate operations defined by the operation definition information related to each of the computers and also another region for describing log information of said computer on the same screen with reference to the information stored into the database by the storage means. It is possible to display relative information between an event and event definition information together with either of them.
[0019] Also, a managing computer, according to a third aspect of the present invention, is featured by such a managing computer connected to a network to which a plurality of computers are connected, for managing these computers, comprising:
[0020] definition means for forming in a batch mode both a schedule of each of administrate operations and operation definition information in which a computer which should execute each of the administrate operations is defined;
[0021] distribution means for distributing the operations definition information;
[0022] acquisition means for acquiring the operation definition information individually formed by the computers from the respective computers and operation definition information in which a portion of the operation definition information distributed by the distribution means and related to the own computer is expanded by the computer from the distributed operation definition information, and also for acquiring log information indicative of an execution result of an administrate operation executed in each of the computers and also event information indicative of an event occurred in an execution stage of the administrate operation from each of said computers;
[0023] storage means for into a database, the operation definition information acquired by the acquisition means, and also the log information and the event information acquired by the acquisition means; and
[0024] display means for displaying the operation definition information related to the respective computers in relation to log information and event information of an administrate operation defined by the operation definition information with reference to the information stored into the database by the storage means.
[0025] It should be understood that each of the computers managed by the managing computer according to the third aspect many expand the operation definition information of a portion related to the own computer from the operation definition information distributed from the managing computer, and also many convert both the log information and the event information of the administrate operation executed by the own computer into a predetermined common format.
[0026] Also, in the third aspect, the above-explained definition means may define such a computer which should execute the administrate operation by employing predetermined information for indicating all of the computers as to the administrate operations to be executed by all of the computers.
[0027] Also, in any of the first aspect to the third aspect, the above-described acquisition means may acquire at regular timing, or preselected timing a predetermined sort of log information among the log information of the respective computers, and further may acquire other sorts of log information when these sorts of log information is required to be displayed by the display means.
[0028] Also, in any of the first aspect to the third aspect, the display means may immediately display either all or a portion of the event information acquired by the acquisition means after being acquired.
[0029] It should also be understood in this specification that a “computer” implies not only an apparatus for merely performing a calculation, but also an apparatus for executing a communication process and further various sorts of information process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] For a more better understanding of the present invention, reference is made of a detailed description to be read in conjunction with the accompanying drawings; in which:
[0031] [0031]FIG. 1 schematically shows an overall structural diagram of a computer system according to an embodiment of the present invention;
[0032] [0032]FIG. 2 is an explanatory diagram for explaining a system arrangement used to form by a managing computer in operation definition information for defining schedules of administrate operations executed by computers;
[0033] [0033]FIG. 3 is an explanatory diagram for explaining a system arrangement used to manage by the managing computer in both log information of administrate operations and event information, executed by the computers;
[0034] [0034]FIG. 4 schematically represents a hardware structural diagram of the managing computer and the computers;
[0035] [0035]FIG. 5 explanatorily indicates a sequential operation for defining/distributing in a batch mode the operation definition information in the system arrangement of FIG. 1, and another sequential operation for acquiring/managing in a batch mode the event information and the log information in the system arrangements of FIG. 3;
[0036] [0036]FIG. 6 is an explanatory diagram for showing an example of the operation definition information defined in a batch mode by the managing computer;
[0037] [0037]FIG. 7A and FIG. 7B are explanatory diagrams for indicating an example of the operation definition information of FIG. 6, which has been expanded;
[0038] [0038]FIG. 8 is an explanatory diagram for representing an example of an integrated management screen displayed in the managing computer;
[0039] [0039]FIGS. 9A and 9B are explanatory diagrams for showing examples of the event information displayed in the managing computer;
[0040] [0040]FIGS. 10A to 10 D are explanatory diagrams for representing examples of structures of various sorts of tables on a database;
[0041] [0041]FIG. 11 is a flow chart for describing a process operation after a job is ended under abnormal state;
[0042] [0042]FIG. 12 is a diagram for indicating a definition of a process operation after the job is ended under abnormal state; and
[0043] [0043]FIG. 13 is a flow chart for explaining a process operation by the managing computer which receives a specific event.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] Referring now to drawings, embodiment modes of the present invention will be described.
[0045] [0045]FIG. 1 schematically indicates an entire arrangement of a computer system according to an embodiment of the present invention. In this drawing, reference numeral 401 indicates a managing computer; reference numerals 402 to 407 computers which constitute subjects managed by the managing computer; and reference numerals 408 to 413 show networks.
[0046] In the computer system according to this embodiment, the managing computer 401 can form in a batch mode operation definition information used to define schedules of administrate operations executed in the computers 402 to 407 , and furthermore the managing computer 401 can manage in a batch mode both log information indicative of execution results obtained from the computers 402 to 407 , and event information indicative of events occurred during execution stage.
[0047] As a result, since the managing computer 401 can save the operation definition information, the log information, and the event information in a database form, this managing computer 401 may refer to the above-described information, if necessary, and also may display various items related to the above-explained information.
[0048] [0048]FIG. 2 schematically represents a system arrangement used to form by the managing computer 401 , the operation definition information which defines the schedules of the administrate operations executed by the computers 402 to 407 . It should be understood that although FIG. 2 represents only one computer 402 and the managing computer 401 of FIG. 1, other computers 403 to 407 may be similarly displayed.
[0049] As indicated in FIG. 2, the managing computer 401 is arranged by a managing application unit 101 , a definition information managing unit 102 , and a database 103 .
[0050] The managing application unit 101 contains a definition unit 104 and an integrated management screen display unit 105 . The batched definition unit 104 forms operation definition information used to define a schedule of administrate operations executed by the computers 402 to 407 . The integrated management screen display unit 105 displays an integrated management screen (will be discussed later) and so on. The definition information managing unit 102 contains a definition information distributing/acquiring unit 106 for distributing the operation definition information to the computers 402 to 407 , and for acquiring the operation definition information from the computers 402 to 407 . This definition information managing unit 102 stores the operation definition information into the database 103 , and retrieves/referring to the operation definition information stored in the database 103 .
[0051] As indicated in FIG. 2, each of the computers 402 to 407 is arranged by employing an operation execution unit and an integrated management agent 113 . This operation execution unit contains a job execution control unit 110 , a power supply control unit 111 , a print execution control unit 112 and the like, which execute the administrate operation defined by the operation definition information.
[0052] The integrated management agent 113 contains a definition information expanding unit 114 and a definition information notifying unit 115 . The definition information expanding unit 114 expands operation definition information of a portion related to the own computer from the operation definition information distributed from the managing computer 401 . The definition information notifying unit 115 notifies to the managing computer 401 , the operation definition information related to the own computer and involving also the operation definition information individually formed by the own computer.
[0053] [0053]FIG. 3 represents a system arrangement in which both log information and event information of administrate operations executed by the computers 402 to 407 are managed in a batch mode by the managing computer 401 . Although FIG. 3 shows only the managing computer 401 and one computer 402 of FIG. 1, other computers 403 to 407 are similarly applied to this computer 402 .
[0054] As indicated in FIG. 3, the managing computer 401 is arranged by employing a managing application unit 101 , an event/log managing unit 201 , and a database 103 .
[0055] The managing application unit 101 contains the integrated management screen display unit 105 for displaying the integrated management screen (will be explained later) and so on. The event/log managing unit 201 contains the event/log acquiring unit 202 for acquiring the event information and the log information from the computers 402 to 407 , and retrieves/refers to the event information and the log information, which are stored in the database 103 . Also, the event/log managing unit 201 stores into the database 103 and outputs to the integrated management screen display unit 105 as to event information which should be notified in real time to an operation manager and so on.
[0056] As indicated in FIG. 3, each of the computers 402 to 407 is arranged by employing an operation execution unit and an integrated management agent 113 . This operation execution unit contains a job execution control unit 110 , a power supply control unit 111 , a print execution control unit 112 and the like, which execute the administrate operation defined by the operation definition information.
[0057] The integrated management agent 113 contains a normalizing unit 210 and an event/log notifying unit 211 . The normalizing unit 210 converts both log information and event information of administrate operation executed by the own computer into a predetermined common format. The event/log notifying unit 211 notifies the normalized log information and the normalized event information to the managing computer 401 .
[0058] [0058]FIG. 4 schematically indicates a hardware structure of the managing computer 401 and the computers 402 to 407 .
[0059] As indicated in FIG. 4, each of the computers is arranged by employing a central processing unit 301 , a main storage apparatus 302 , a network control apparatus 305 , a disk control apparatus 307 , and a display control apparatus 309 . The network control apparatus 305 controls input/output of data between this network control apparatus 305 and a network such as a communication line 303 and a local area network 304 . The disk control apparatus 307 controls a disk apparatus 306 and also input/output thereof. The display control apparatus 309 controls a display apparatus 308 and also input/output thereof.
[0060] Among the structural blocks of FIG. 2 and FIG. 3, the database 103 is realized on the disk apparatus 306 . Other structural blocks are realized in such a way that a program stored in the disk apparatus 306 is loaded by the central processing unit 301 on the main storage apparatus 302 . It should be noted that this program may be recorded on, for instance, a recording medium such as a CD-ROM, and then may be read into a driver (not shown) to be stored into the disk apparatus 306 .
[0061] Referring now to FIG. 5, a description will be made of a sequential operation for defining and distributing the operation definition information in the system arrangement of FIG. 2.
[0062] As indicated in FIG. 5, in the managing computer 401 , the definition information managing unit 102 stores into the database 103 , the operation definition information defined by the batched definition unit 104 contained in the managing application unit 101 (step 601 ). The operation definition information stored in the database 103 is distributed to the computers 402 to 407 at preselected timing by the definition information distributing/acquiring unit 106 contained in the definition information managing unit 102 (step 602 ).
[0063] In the computers 402 to 407 to which the operation definition information is distributed, the definition information expanding unit 114 owned by the integrated management agent 113 expands operation definition information of a portion related to the own computer from the distributed operation definition information. The definition information expanding unit 114 transfers the expanded operation information to the operation execution unit such as the job execution control unit 110 , the power supply control unit 111 , and the print execution control unit 112 (step 603 ). The operation execution unit executes the administrate operation defined by the respective transferred operation definition information (step 604 ).
[0064] On the other hand, in the managing computer 401 , the definition information distributing/acquiring unit 106 of the definition information managing unit 102 acquires from the computers 402 to 407 , the operation definition information related to the computers 402 to 407 and also containing the operation definition information individually formed in the computers 402 to 407 (step 605 ). Subsequently, the definition information managing unit 102 stores the acquired operation definition information into the database 103 (step 606 ).
[0065] In the case that the integrated screen display unit 105 owned by the managing application unit 101 displays an integrated management screen (will be explained later) in response to a reference request issued from an operation manager and the like, the operation definition information stored into the database 103 in this manner will be retrieved/referred by the definition information managing unit 102 .
[0066] It should be understood that the operation definition information may be acquired in such a way that the definition information distributing/acquiring unit 106 contained in the definition information managing unit 102 in the managing computer 401 periodically issues a command to the computers 402 to 407 . Alternatively, the acquisition of the operation definition information may be realized by such that the definition information notifying unit 115 owned by the integrated management agent 113 in the computers 402 to 407 initiatively notifies the operation definition information to the managing computer 401 at preselected timing.
[0067] [0067]FIG. 6 shows an example of operation definition information which is defined by the managing computer 401 . In this drawing, reference numeral 701 shows operation definition information.
[0068] In a definition of the operation definition information 701 , a “definition subject 710 ” corresponds to a portion for defining a computer to be defined. The definition subject 710 may designate a group constituted by a plurality of computers, and a single computer. As represented in FIG. 6, it should be understood that when predetermined information (in this case, “default”) is designated in “definition subject 710 ”, this information implies that all of the computers are the definition subjects.
[0069] A “power supply control ( 711 )” corresponds to a portion used to define an execution schedule of a power supply turning ON/OFF process of a computer to be defined, and a turning OFF method. A “job execution control ( 712 )” corresponds to a portion used to define a job net on a computer to be defined, and a job on the job net. In the example of FIG. 6, a “job net A” defines that after an execution of a “job A 1 ” has been completed, a “job A 21 ” and a “job A 22 ” are executed in a parallel manner, and then when the executions of both these jobs A 21 and A 22 are completed, a “job A 3 ” is executed.
[0070] As previously explained, since the operation manager and the like designate such a computer for executing the schedule of the respective administrate operations and also the respective administrate operations in the managing computer 401 , the operation definition information can be formed in a batch manner, on which the schedule of the administrate operation to be executed by the computer is defined.
[0071] [0071]FIG. 7A and FIG. 7B show an example of the operation definition information 701 of FIG. 6 which is expanded by the computer. In FIG. 7A and FIG. 7B, there are shown operation definition information 801 to 802 which have been expanded in the computers 402 to 407 of FIG. 2. Each of the above-described operation definition information 801 and 802 is transferred to the power supply control unit 111 and the job execution control unit 110 .
[0072] Next, a sequential operation for acquiring and for managing in a batch mode the event information and the log information in the system arrangement of FIG. 3 will now be described with reference to FIG. 5.
[0073] As indicated in FIG. 5, in such a case that either the event information or the log information notified from the administrate operation unit is equal to a preselected sort of information which should be notified to the managing computer 401 , the normalizing unit 210 owned by the integrated management agent 113 in each of the computers 402 to 407 converts this event, or log information into a common format to which a discrimination of event/log information is added. Then, the converted common format is notified by the event/log notifying unit 211 to the managing computer 401 (step 610 ).
[0074] In the managing computer 401 to which either the event information or the log information is notified, the event/log acquiring unit 202 owned by the event/log managing unit 201 stores the notified event information, or the notified log information into the database 103 (step 611 ). The log information is related to an abnormal state occurred during processing operation and includes information related to an abnormal state occurred during processing operation, whereas the event information is such information which is more important and concise than the former and necessary to inform to the manager computer in real time as to an urgent abnormal event occurred in the operation stage to be cared for by an operator. As a result, in the case that the event information is notified, it is preferable to immediately display this event information on the display apparatus 308 by the integrated management screen display unit 105 owned by the managing application unit 101 (step 612 ). It should also be noted that information may be discriminated as either log information or event information based upon discrimination contained in this information. As another embodiment, this information may be discriminated as either log information or even information based upon the path through which this information is transferred.
[0075] As explained above, in the case that the integrated management screen display unit 105 owned by the managing application unit 101 displays an integrated management screen (will be explained later) in response to a reference request sent from the operation manager, both the event information and the log information stored in the database 103 are retrieved/referred by the definition information managing unit 102 .
[0076] The notifications of the event information and the log information may be preferably realized as to such event information with a high real time characteristic (in particular, event information indicative of failure) as follows. In the computers 402 to 407 , the event/log notifying unit 211 owned by the integrated management agent 113 initiatively notifies the event information to the managing computer 401 . As to the notification of the log information, in the managing computer 401 , the event/log acquiring unit 202 owned by the event/log managing unit 201 may be realized by regularly issuing a command to the computers 402 to 407 . Alternatively, the notification of the log information may be realized by that in the computers 402 to 407 , the event/log notifying unit 211 owned by the integrated management agent 113 initiatively notifies the log information to the managing computer 401 at preselected timing.
[0077] Subsequently, referring now to FIG. 8, a description will be made of one example of an integrated management screen which is displayed by the integrated management screen display unit 103 owned by the managing application unit 101 in the managing computer 401 .
[0078] As previously explained, since the operation definition information, the event information, and the log information are stored in the database 103 in the managing computer 401 , the operation manager and the like may grasp the operations conditions of the computer system by utilizing the above-explained information. In other words, within the managing computer 401 , the integrated management screen display unit 105 owned by the managing application unit 101 causes the definition information managing unit 102 to retrieve/refer to such information which is required by the operation manager to refer to. Then, this integrated management screen display unit 105 forms as integrated management screen by using the retrieved/referred information, and displays the formed integrated management screen on the display apparatus 308 . As a result, the operation manager can grasp the operation condition of the computer system by observing the integrated management screen displayed on the display apparatus 308 .
[0079] In FIG. 8, a first screen 501 is an integrated management screen used to confirm computers managed by the managing computer 401 and also to confirm a group of these computers. In this example, four sets of computers A to D are indicated. The respective computers A to D are displayed as icons. For example, in the first screen 501 , the operation manager double-clicks “computer A ( 502 )” by using a mouse, so that the first screen 501 can be transferred to a second screen 503 .
[0080] Also, in FIG. 8, the second screen 503 is an integrated management screen used to confirm an operation condition of “computer A ( 502 )”. With respect to the “computer A ( 502 )”, a present job execution condition ( 504 ), a list ( 505 ) of a job net whose execution is defined on the “computer A”, and a list ( 506 ) of log information corresponding to a past operation history are displayed in a message form on this second screen 503 . For example, when the operation manager wants to confirm an operation condition related to “job net A” on the second screen 503 , the operation manager double-clicks a column related to “job net A” listed in the job net list 505 by using the mouse, so that the second screen 503 can be transferred to a third screen 507 .
[0081] Also, in FIG. 8, the third screen 507 is an integrated management screen related to “job net A” on “computer A”. This integrated management screen indicates such operation definition information on which a series of administrate operations are defined as to “computer A”, i.e., “turning ON of power supply ( 509 )”, “execution of job net A ( 510 )”, and “printing of execution result ( 511 )”.
[0082] It should be noted that these administrate operations 509 to 511 are displayed as icons. Since a display mode of each of these icons is changed (for instance, color and shape are changed), various sorts of conditions may be displayed such as “not yet executed”, “under execution”, “execution is ended under normal state”, and “execution is ended under abnormal state”. In this case, when the display modes of the respective icons are changed by the integrated management screen display unit 105 , the latest event information of the corresponding administrate operations ( 509 to 511 ) is preferably acquired by the event/log acquiring unit 202 owned by the event/log managing unit 201 .
[0083] For example, when “job net A ( 501 )” is double-clicked by using the mouse by the operation manager, the third screen 507 can be transferred to a sixth screen 514 .
[0084] Also, in FIG. 8, a fifth screen 512 corresponds to an integrated management screen used to confirm the operation definition information displayed on the third screen ( 507 ) in a calendar format. For example, since the operation manager selects menu of “calendar display” (not shown) on the third screen 507 , the third screen 507 can be transferred to the fifth screen 512 . In this example, this fifth screen 512 displays that the job seen on the third screen is executed on a date 513 of a hatched portion.
[0085] Also, in FIG. 8, a sixth screen 514 is a detailed integrated management screen related to “job net A” on “computer A”. This sixth screen 514 defines such that as to “job net A”, after an execution of “job A 1 ( 515 )” is completed, both “job A 21 ( 516 )” and “job A 22 ( 517 )” are executed in a parallel manner, and when the executions of both “job A 21 ( 516 )” and “job A 22 ( 517 )” are completed, “job A 3 ( 518 )” is executed.
[0086] It should also be noted that these jobs are displayed as icons. Since a display mode of each of these icons is changed (for instance, color is changed), various sorts of conditions may be displayed such as “not yet executed”, “under execution”, “execution is ended under normal state”, and “execution is ended under abnormal state”. In this case, when the display modes of the respective icons are changed by the integrated management screen display unit 105 , the latest event information of the corresponding administrate operations ( 509 to 511 ) is preferably acquired by the event/log acquiring unit 202 owned by the event/log managing unit 201 .
[0087] Also, in FIG. 8, a fourth screen 508 corresponds to an integrated management screen used to confirm a log with respect to each of job nets. For instance, since the operation manager double-clicks a list ( 506 ) of the log information on the second screen 503 , the second screen 503 can be transferred to the fourth screen 508 . Alternatively, for example, while the operation manager designates a column related to “job net A” within the job list 505 by clicking this column by using the mouse, this operation manager selects menu of “log display” (not shown). As a result, the second screen 503 may be transferred to another screen (not shown) on which only log information of “job net A” is displayed.
[0088] It should be understood that when the operation manager selects, for example, the corresponding menu within any of the second screen 504 to the sixth screen 514 , the present screen may be transferred to other screens involving such not-shown screens (event information display screen, statistical display screen, operation definition information updating screen etc.). It will be possible to click a certain message shown in screen 508 to additionally display the window 514 or 507 as indicated with arrows.
[0089] As previously explained, in accordance with this embodiment, in the managing computer 401 , the operation definition information related to the respective computers is displayed in connection with both the log information and the event information of the administrate operations defined by this operation definition information. As a consequence the operation manager can grasp the operation conditions of the computer system, and furthermore can readily reflect the grasped operation conditions onto a further plan of the operation schedule.
[0090] As previously described, after the event information is notified, the managing computer 401 preferably and immediately displays this notified event information on the display apparatus 308 . At this time, a screen displayed in the managing computer 401 is represented in, for instance, FIG. 9A.
[0091] [0091]FIG. 9A represents an example of a screen on which event information of a computer A is displayed as a message among the notified event information. In this drawing, the message is constructed of an importance degree 901 of the event information, day/time 902 to 903 when the event is notified, a computer 904 of a notification source, and a message main body 905 .
[0092] The managing computer 401 may display all of the notified event information as a message. Alternatively, as indicated in FIG. 9B, the managing computer 401 may display only pre-designated sorts of event information. As a pre-designated basis, the following items may be conceived, e.g., an importance degree; a range for a date and a time instant; a computer of a notification source; a sort of administrate operation; and a pattern of a character string contained in event information. The operation manager may designate a sort of event information displayed as a message by either the managing computer 401 or the respective computers 402 to 407 .
[0093] Then, in the managing computer 401 , the event/log managing unit 201 judges as to whether or not the notified event information is displayed as the message. The event/log managing unit 201 immediately notifies to the integrated management screen display unit 105 owned by the managing application unit 101 , such event information which is judged to be displayed as a message. Then, the integrated management screen display unit 105 displays this judged event information. Therefore, for instance, as represented in FIG. 9, only such event information indicative of a failure may be displayed as a message. It should be understood that event/log managing unit 201 stores the notified event information into the database 103 irrespective of such a judgment result as to whether or not the notified event information is displayed as the message.
[0094] [0094]FIG. 10A and FIG. 10B represent one example of structures of various sorts of tables on the database 103 . In the drawings, reference numeral 1001 shows an event/log table, and reference numeral 1002 indicates an operation definition table.
[0095] The event/log table 1001 is such a table used to store thereinto the events and the log information acquired from the computer by the managing computer 401 in a time sequence. A single record is arranged by “identifier ( 1010 )” “computer name ( 1011 )”, “time ( 1012 )”, “event/log sort ( 1013 )”, “identifier ( 1014 )”, and “detailed information ( 1015 )”. The identifier 1010 is for the event information and the log information. The computer name 1011 is a name of a computer for notifying this information. The time 1012 is time when this information is notified. The sort 1013 is the sort of this information. The identifier 1014 is an identifier of operation definition information on which administrate operation where this information is produced is defined. In the computer, the information 1010 to 1014 other than the detailed information 1015 is normalized as the common format commonly used to all of the event information and the log information by the normalizing unit 210 owned by the integrated management agent 113 .
[0096] As indicated in FIG. 10B to FIG. 10D, an operation definition table 1002 is constituted by a common table 1003 arranged by an identifier 1016 of operation definition information, a name ( 1017 ) of a computer to be defined, and a sort ( 1018 ) of operation definition information; and also operation definition detailed tables 1004 to 1005 corresponding to the respective sorts ( 1018 ) of the operation definition information.
[0097] The operation definition detailed table 1004 related to the power supply control is arranged by, for example, an identifier ( 1019 ) of operation definition information; a power supply initiation date ( 1020 ); a power supply initiation time ( 1021 ); and a power supply turn-OFF date ( 1022 ), and also a power supply turn-OFF time ( 1023 ). The operation definition detailed table 1005 related to the job net is arranged by, for instance, an identifier ( 1024 ) of operation definition information; a name ( 1025 ) of a job net; a job net initiation date ( 1026 ); a job net initiation time ( 1027 ); and a structural job ( 1028 ).
[0098] In the managing computer 401 , both the definition information managing unit 102 and the event/log managing unit 201 retrieve the tables 1001 to 1004 shown in FIG. 10A to FIG. 10D based on a language of, for instance, SQL. As a result, the integrated management screen display unit 105 owned by the managing application unit 101 can display such a screen as indicated in FIG. 8. In particular, the relationship among the event information, the log information, and the operation definition information may be established by employing the identifier ( 1014 ) of the operation definition information contained in the event/log table 1001 and the identifiers 1016 , 1019 , 1024 of the operation definition information contained in the operation definition table 1002 .
[0099] It should be noted that when the screen is displayed, in such a case that information required to be displayed is not present in the tables 1001 to 1004 of FIG. 10, the managing computer 401 is operated in a similar manner to that shown in FIG. 5 so as to acquire this information required to be displayed.
[0100] In the case that such information indicative of a failure occurred in operation conditions of the computer system is notified as an event, this computer system may be operated as follows. First, for example, when a specific job is accomplished under abnormal state while a job net is being executed, after removing a factor for causing this abnormally ended job (e.g., a specific file required to execute a job is not present), the computer system may instruct that this interrupted job is restarted. This instruction may be realized as follows. That is, as indicated in FIG. 11 , in the managing computer, “reexecution command” for designating “subject computer”, “job net name”, “job name to be reexecuted” is entered ( 1101 ); this command is transferred to the above-explained subject computer ( 1102 ) so as to be executed ( 1103 ). Secondly, the computer system may instruct this job net to be canceled. This second idea may be realized as follows. That is, as shown in FIG. 11, in the managing computer, “cancel command” for designating “subject computer ” and “job net name” is entered ( 1101 ); this command is transferred to the above-described subject computer ( 1102 ) so as to be executed ( 1103 ). Furthermore, thirdly, when a specific job is ended under abnormal state while a job net is being executed, a specific job and also a specific job net, by which an abnormal end event is previously defined as a trigger, may be executed. This alternative method may be realized as follows. That is, as represented in FIG. 12, while the managing computer defines such a process operation which should be executed when a specific event is received ( 1201 ), when the managing computer receives this specific event as shown in FIG. 13 ( 1301 ), this managing computer instructs a subject computer to execute the designated process operation ( 1302 ). Then, the subject computer may execute this instruction ( 1303 ). At this time, the definition of either the job or the job net which should be executed by the subject computer may be transferred to be registered when the instruction is issued. Otherwise, this definition may be previously transferred to be registered.
[0101] Subsequently, a description will now be made of effects achieved in such a case that the operation definition information, the event information, and the log information are processed in the database form by the managing computer 401 to be stored.
[0102] As a first effect, a network traffic can be reduced. In accordance with the present invention, since the operation definition information, the event information, and the log information are stored in the database form by the managing computer 401 , the managing computer 401 need not acquire the necessary information from the computer every time the operation manager and the like refer to these information.
[0103] For instance, in the network structure of FIG. 1, when log information of 1 K bytes is acquired from each of the six computers 402 to 407 by the managing computer at a frequency of 1,000 messages/day, a network traffic of 6 M bytes/day is produced. In the case that the log information is referred by the operation manager at a frequency of 10 times/day, a network traffic of 60 M bytes/day in total is produced.
[0104] Furthermore, as to such log information with a low demand of a real-time characteristic, if such log information is collected within such a time range where the normal network traffic is low, for example, in a night time range, the network traffic reduction effect can be apparently achieved.
[0105] As a second effect, since the operation definition information, the event information, and the log information are stored in the database form by the managing computer 401 , as represented in the integrated management screen of FIG. 8, there is another effect that the above-explained information can be readily displayed in various relationship aspects.
[0106] In the computer system according to this embodiment, the computers 402 to 407 are set to be defined in a batch mode by the managing computer 401 . However, it is conceivable that other computers which do not constitute a definition subject are connected to the networks 408 to 413 . In this case, as a method for recognizing a subject computer to be managed by the managing computer 401 , for example, there is a method for automatically detecting the integrated management agent 113 assembled into the computer by using, for example, a broadcasting method. As another method, a subject computer to be defined may be previously defined on the managing computer 401 .
[0107] Also, in accordance with the computer system according to this embodiment, the operation definition information in which the schedule of the administrate operations executed by the computers 402 to 407 is defined can be formed in a batch mode by the managing computer 401 , and furthermore both the log information and the event information of the administrate operations executed by the computers 402 to 407 can be managed by the managing computer 401 , resulting in better results. Alternatively, if at least both the log information and the event information can be managed, then the operation manager may grasp the operation condition of the computer system.
|
A managing computer is arranged by an acquiring device for acquiring log information and event information from any of plural computers connected via a network to each other, the log information indicating as to whether or not an execution of an operation process is carried out under normal condition, and the event information indicating concisely as to whether or not an execution of an operation process is carried out under normal condition; a data controller for storing into a database, operation definition information used to define a schedule of process operations executed in the plural computers in relation to the log information and the event information acquired by the acquiring device; and a display device for displaying the operation definition information in relation to event information related to a process operation defined by the operation definition information with reference to the information stored in the database. Each of the log information and the event information owns a tag indicative of said log information and a tag representative of said event information. This managing computer may have a definition device for forming a schedule of process operations which are commonly executed in all of the plural computers; and a distributor for distributing the process operation schedule formed by the definition device to all of the plural computers. The display device displays on the same display screen, the operation definition information and the event information in relation to predetermined log information among the log information. The acquiring device acquires a preselected sort of log information at predetermined timing. The acquiring device acquires information other than the preselected sort of log information in response to a request. Thus, an integrated management screen can be provided to a user.
| 7
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a method and apparatus for interconnecting circuit boards and, in particular, to circuit boards adapted to be housed within an enclosure. This invention further relates to a method and apparatus for interconnecting circuit boards of different modules, wherein a module comprises two circuit boards.
[0003] 2. Statement of the Problem
[0004] Circuit boards are widely used in electronic devices and systems. It is commonplace to use a plurality of circuit boards in a television, a laptop computer, a mobile telephone, an MP3 player, a digital voice recorder, etc. In general, the more complex the device, the greater number of circuit boards that are required for the device.
[0005] It is a problem in the industry to use multiple boards within a device because of problems related to efficiently and economically mounting and interconnecting the multiple boards to each other. Industry standard specification PC 104 characterizes the recommended specifics of stacking or mounting a plurality of circuit boards vertically. This standard specifies that vertically stacked circuit boards must have a ½″ space between them. The component's are mounted on only one side of the circuit board and are contained within this ½″ spacing. This ½″ spacing increases the overall size of the device containing the stacked circuit boards. Thus, a device containing four circuit boards would have a height of 2″; a device with six circuit boards would have a height of 3″, etc. Compliance with this standard precludes such devices from being used in laptops, mobile telephones and other devices that must be thin to be commercially attractive.
[0006] The PCI standard characterizes the requirements for devices containing a motherboard or backplane. The requirements include having a plurality of the circuit boards spaced at least ½″ from each other, connecting the circuit boards at right angles to the motherboard or backplane. Compliance with this standard precludes the use of the circuit boards and the motherboard in devices such as cell phones of a like where the devices must be thin in order to be commercially acceptable.
[0007] In accordance with the PC 104 and PCI standards, electronic elements such as resistors, capacitors, coils, transformers, etc. are positioned on only one side of the board in the ½″ spacing between circuit boards. When the components are of a heat generating type, it is difficult to mount the components in this ½″ spacing because of thermal problems created by the generated heat. This in turn, may require the use of fans and the like to maintain a satisfactory temperature of the circuit boards and its components. Further, the use of motherboards connected to multiple circuit boards presents a problem protecting the boards from vibrations.
[0008] It can be seen that prior art arrangements having multiple circuit boards creates problems that preclude their use in miniaturized devices. These problems include space, thermal, and vibration problems.
SUMMARY OF THE SOLUTION
[0009] The present invention solves the above and other problems by the provision of a method and apparatus that provides for the interconnection of multiple modules and circuit boards within a device. In accordance with the invention, a module is provided which comprises multiple circuit boards interconnected with a plurality of connectors. Further, a pair of circuit boards, herein referred to as a module, may also be interconnected to other like modules. The multiple circuit boards and modules are interconnected by contacts that permit the circuit boards and modules to be removably coupled to each other, and that permit circuit boards to be positioned by a spaced amount that results in a small spacing between circuit boards. This small spacing facilitates the use of modules in miniaturized devices where small dimensions are a prerequisite to commercial success of the devices. The use of the method and apparatus of the present invention permits the use of the modules in mobile telephones, laptop computers, MP3 players, digital voice recorders, etc., where space is at a premium. This enables devices housing the circuit boards to be commercially attractive by permitting the device to have increased functionality without an increase in size.
[0010] The method and apparatus of the present invention also permits the removal and insertion of modules. This permits a module to be removed for maintenance and then repaired or replaced by another module. This is particularly advantageous since it permits a working device to be easily repaired instead of being discarded since it is often not feasible to repair a single motherboard and/or a plurality of a circuit boards interconnected by wires and the like.
[0011] The ability of the modules to be removed is advantageous since it permits modules to be used for different applications by inserting a combination of modules into the device to create a device having a required functionality. This feature allows a manufacturer to store generic modules that can be stored and later converted into a device having a specific functionality by the insertion of a specific combination of modules. This feature permits a manufacturer or assembler to store a fewer number of parts that can be converted to a specific use using different types of circuit boards and modules.
[0012] The method and apparatus of the present invention is further advantageous in that it provides increased thermal capabilities for the module in which it is used. This is achieved by thermally coupling components to the faces of a module, with the face being in contact with surreally conductive material that dissipates heat by conduction rather than by thermal convection requiring airflow. This permits a device to use modules of smaller size since space does not have to be provided within the device to accommodate airflow or the like.
[0013] The method and apparatus of the present invention is ubiquitous in that the modules are equipped with contacts along the perimeter of their top and bottom faces. This permits modules to be placed side-by-side or stacked vertically. When the modules are vertically positioned, they are interconnected to each other by engaging the perimeter contacts of stacked modules to each other. These perimeter contacts also permit modules to be horizontally positioned in the same plane and connected to each other by a thin connector sheet that enables a module to be connected to an adjacent module by pressing the connector sheet down so that its contacts interconnect the perimeter contacts of the adjacent modules.
[0014] The contacts may be on one or all of the perimeters of the module. This provides great flexibility in the assembly of a device using a plurality of modules with different functionality. For example, a device can be equipped with a single pair of circuit boards (i.e., a module). Also, a device can have modules positioned in a plane and connected to each other by their perimeter contacts. A device may also have modules vertically stacked atop each other. Further, a device may have any number of horizontally interconnected modules as well as any number of vertically stacked modules.
[0015] The space between the upper and lower circuit boards of a module is used to mount components on one side of each circuit board. The components may be controllably positioned on the surface of the lower and upper circuit boards of the module. The components on the upper or lower circuit boards of a module may be positioned so that a tall element on one of the circuit boards does not abut a tall element on the other circuit board. In other words, a tall element on a lower circuit board may be positioned vertically opposite a smaller element on the upper circuit board, or vice versa. The capability of positioning the elements in this manner permits a smaller spacing between two vertical circuit boards of a module, since the component's on adjacent vertical circuit boards are controllably positioned to fill the space available between the two circuit boards.
[0016] In use, modules may be stacked vertically and mounted within an enclosure so that the lower surface of the bottom circuit board of the module abuts the lower surface of the enclosure. The top surface of the top circuit board of the module engages the bottom surface of the upper wall of the enclosure. This provides for increased thermal capabilities as above discussed.
[0017] The invention may include other exemplary embodiments described below.
DESCRIPTION OF THE DRAWINGS
[0018] The above and other advantages and features of the invention may be better understood from a reading of the detailed description taken in conjunction with the drawings. The same reference number represents the same element on all drawings.
[0019] FIG. 1 is an exploded top isometric view of a module in an exemplary embodiment of the invention.
[0020] FIG. 2 is an exploded bottom isometric view of a module in an exemplary embodiment of the invention.
[0021] FIG. 3 is an isometric view of a module in an exemplary embodiment of the invention.
[0022] FIG. 4 is an exploded top isometric view of a 3×2 enclosure adapted to house a plurality of modules in an exemplary embodiment of the invention.
[0023] FIG. 5 is an exploded bottom isometric view of a 3×2 enclosure adapted to house a plurality of modules in an exemplary embodiment of the invention.
[0024] FIG. 6 is a top view of a 3×3 enclosure adapted to house a plurality of modules in an exemplary embodiment of the invention.
[0025] FIG. 7 is an exploded isometric view of a multi-layered enclosure adapted to house a plurality of layers of modules in an exemplary embodiment of the invention.
[0026] FIG. 8 is a side view of the connection between the two circuit boards of a module in an exemplary embodiment of the invention.
[0027] FIG. 9 is a side view of two modules matingly engaged in a stacked configuration in an exemplary embodiment of the invention.
[0028] FIG. 10 is a side view of two modules matingly engaged in a side-by-side configuration in an exemplary embodiment of the invention.
[0029] FIG. 11 is an isometric view of a row of inside contacts in an exemplary embodiment of the invention.
[0030] FIG. 12 is an isometric view of a row of outside contacts in an exemplary embodiment of the invention.
[0031] FIG. 13 is an isometric view of insulator material separating the top outside contacts, the bottom outside contacts, and the inside contacts in an exemplary embodiment of the invention.
[0032] FIG. 14 is an isometric view of an apparatus adapted to connect a module to an external device in an exemplary embodiment of the invention.
[0033] FIG. 15 is a flow chart of a method for forming a module in an exemplary embodiment of the invention.
ASPECTS
[0034] An aspect of the invention comprises a system, the system including at least one module. The module comprises a first circuit board having a component surface; a second circuit board having a component surface, the component surface of the second circuit board disposed facing the component surface of the first circuit board; and an apparatus adapted to physically and electrically couple the first circuit board and the second circuit board, and further adapted to matingly engage the module with a second module.
[0035] Preferably, the apparatus for physically and electrically coupling the first circuit board and second circuit board comprises: a plurality of outside spring leaf contacts that clamp the outer sides of the first and second circuit boards along each edge of the first and second circuit boards to keep the first and second circuit boards from moving apart, each outside spring leaf contact extending beyond the outer faces of the first and second circuit boards and adapted to matingly engage contact pads on the outer faces of the module with the second module; and a plurality of inside spring leaf contacts pressed between the component sides of the first and second circuit boards along each edge of the first and second circuit boards to keep the first and second circuit boards from moving together, each inside spring leaf contact adapted to matingly engage with contact pads on the component sides of the first and second circuit boards to electronically couple the first circuit board and the second circuit board.
[0036] Preferably, the apparatus for physically and electrically coupling the first circuit board and second circuit board further comprises: insulator material substantially a same length as an edge of the module, the insulator material having a plurality of slots adapted to electrically isolate each pair of matingly engaged outside spring leaf contacts and inside spring leaf contacts from other pairs of matingly engaged outside spring leaf contacts and inside spring leaf contacts.
[0037] Preferably, the plurality of outside spring leaf contacts further comprises: at least one power contact; at least one ground contact; at least one control signal contact; and at least one data signal contact.
[0038] Preferably, the system comprises a plurality of modules.
[0039] Preferably, sizes of each edge of the first circuit board and the second circuit board are integer multiples of a base value.
[0040] Preferably, the first circuit board and the second circuit board further comprise means for securing the module in place in an enclosure housing the module.
[0041] Preferably, the module comprises: a cut-out on each of the four corners of the first circuit board, and a cut-out on each of the four corners of the second circuit board, the cut-outs on the first circuit board and the cut-outs on the second circuit board adapted to pass through a spacer in the enclosure housing the module to secure the module in place around the spacer.
[0042] Preferably, the enclosure comprises a plurality of spacers arranged in a grid pattern, each spacer being equally spaced apart in an X-direction and a Y-direction of the enclosure, with the base value equal to a distance between centers of two of the plurality of spacers.
[0043] Another aspect of the invention is a system comprising: a plurality of modules, each module comprising: a first circuit board having a component surface; and a second circuit board having a component surface, the component surface of the second circuit board disposed facing the component surface of the first circuit board; and an apparatus adapted to physically and electrically couple the first circuit board and the second circuit board and adapted to matingly engage the module with at least one of the other plurality of modules, and the system further comprising an enclosure adapted to house the plurality of modules; and a plurality of spacers coupled to the enclosure, the plurality of spacers arranged in a grid pattern, each spacer being equally spaced apart in an X-direction and a Y-direction of the grid pattern, wherein sizes of each edge of the first circuit board and the second circuit board of each module are integer multiples of a base value, the base value equal to a distance between centers of two of the plurality of spacers.
[0044] Preferably, the apparatus for physically and electrically coupling the first circuit board and second circuit board comprises: a plurality of outside spring leaf contacts that clamp the outer sides of the first and second circuit boards along each edge of the first and second circuit boards to keep the first and second circuit boards from moving apart, each outside spring leaf contact extending beyond the outer faces of the first and second circuit boards and adapted to matingly engage contact pads on the outer faces of the module with the second module; and a plurality of inside spring leaf contacts pressed between the component sides of the first and second circuit boards along each edge of the first and second circuit boards to keep the first and second circuit boards from moving together, each inside spring leaf contact adapted to matingly engage with contact pads on the component sides of the first and second circuit boards to electronically couple the first circuit board and the second circuit board.
[0045] Preferably, the system comprises a plurality of layers of modules housed in the enclosure, wherein at least one layer of modules is stacked atop a lower layer of modules.
[0046] Preferably, the plurality of layers of modules are electronically coupled together by the outside spring leaf contacts, the outside spring leaf contacts electrically coupling a first module on a first layer and a second module on a second layer, the second module stacked atop the first module.
[0047] Preferably, the system comprises an apparatus adapted to electrically couple at least one of the plurality of modules with an external device, the apparatus comprising: a cable electrically coupled to the apparatus module, the cable adapted to electrically couple the apparatus module with the external device.
[0048] Another aspect of the invention are modules with footprints that are restricted to closed shapes that can be constructed by arranging segments of a unit length end-to-end such that all segments are either parallel or perpendicular to one-another and where said modules have a plurality of electrical contacts centered along the edge of at least one of said segments and extending above and below the edge such that a plurality of modules can be electrically connected to one-another by way of said contacts when said plurality of modules are stacked atop one-another.
[0049] Preferably, the modules are also arranged side-by-side in a plane and connected by an apparatus that contains conductive strips where said apparatus is oriented parallel to said modules in order to mate with said perimeter contacts of both modules in order to effect electrical connection between the contacts of said modules.
[0050] Another aspect of the invention is a method for forming a module, the method comprising: providing a first circuit board having a component surface; providing a second circuit board having a component surface, the component surface of the second circuit board disposed facing the component surface of the first circuit board; and positioning components on the component surface of the first circuit board and the component surface of the second circuit board to minimize un-utilized space between the first circuit board and the second circuit board.
[0051] Preferably, there is a first height between the first circuit board and the second circuit board, and positioning components further comprises: positioning a first component on the component surface of the first circuit board, the first component having a second height less than the first height; determining a remaining height based on the first height minus the second height; and positioning a second component on the component surface of the second circuit board, the second component having a third height which is less than or equal to the remaining height.
DETAILED DESCRIPTION OF THE INVENTION
[0052] FIGS. 1-15 and the following description depict specific exemplary embodiments of the invention to teach those skilled in the art how to make and use the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects of the invention have been simplified or omitted. Those skilled in the art will appreciate variations from these embodiments that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific embodiments described below, but only by the claims and their equivalents.
[0053] FIG. 1 is an exploded isometric view of a module 100 in an exemplary embodiment of the invention. FIG. 1 illustrates an internal view of the bottom of module 100 . Module 100 includes a bottom circuit board 101 and a top circuit board 102 . Top circuit board 102 has a component surface (not visible in FIG. 1 ) which is disposed facing a component surface of bottom circuit board 102 . The component surface of bottom circuit board 102 contains components 112 and 113 of differing heights. The terms top and bottom are used for illustrative purposes only. Module 100 may be oriented in any number of directions such that bottom circuit board 101 and top circuit board 102 may be disposed in opposite positions, or may comprise opposite sides of module 100 . Module 100 includes a connector 103 adapted to physically and electrically couple bottom circuit board 101 and top circuit board 102 . To electrically couple bottom circuit board 101 and top circuit board 102 , the connector 103 comprises a plurality of inside contacts 107 that engage inside contact pads 108 A on circuit board 102 with contact pads 108 B (not visible in FIG. 1 ) on circuit board 101 . The engagement of bottom inside contact pads 108 B and top inside contact pads 108 A will be subsequently described. As illustrated in FIG. 1 , there are twenty-five pairs of bottom inside contacts 108 B and top inside contacts 108 A along each edge of module 100 . However, any number of pairs of bottom inside contacts 108 B and top inside contacts 108 A may be disposed along each edge of module 100 depending on desired design criteria.
[0054] The coupling apparatus of module 100 may further include a plurality of outside contacts 109 A and 109 B adapted to matingly engage module 100 with another like module (not shown) to electrically couple the two modules. A portion of outside contacts 109 B and 109 A are electrically coupled to bottom outside contact pads 110 B (not visible in FIG. 2 ) of circuit board 101 and outside contact pads 110 A of circuit board 102 respectively to electrically couple bottom circuit board 101 and top circuit board 102 with other modules. As illustrated in FIG. 1 , there are thirteen outside contacts 109 A on the top and thirteen outside contacts on the bottom along each edge of module 100 . Thus, thirteen top outside contacts 109 A may be electrically coupled to another module on each side of module 100 and thirteen bottom outside contacts 109 B may be electrically coupled to another module on each side of module 100 . Module 100 as illustrated may be electrically coupled to eight other modules, two on each side of module 100 .
[0055] Corner clips 104 are captured between circuit boards 101 and 102 when corner clip posts 105 A and 105 B pass through holes 106 A and 106 B respectively in circuit boards 102 and 101 respectively. Said corner clips hold connectors 103 to module 100 by way of tab 114 of connector 103 snapping into slot 115 of corner clip 104 .
[0056] Bottom circuit board 101 includes a plurality of cut-outs 111 B on each corner of bottom circuit board 101 . Top circuit board 102 includes a corresponding plurality of cut-outs 111 A on each corner of top circuit board 102 . The cut-outs 111 A and 111 B are adapted to secure module 100 in place in an enclosure (not shown in FIG. 1 ). The enclosure and securing of module 100 within the enclosure will be subsequently described.
[0057] FIG. 3 is an isometric view of module 100 in an exemplary embodiment of the invention. More specifically, FIG. 3 illustrates the final assembly of module 100 after bottom circuit board 101 and top circuit board 102 are physically and electrically coupled by connectors 103 and corner clips 104 . While module 100 is illustrated as a square, module 100 may be other types of parallelepipeds, such as a rectangle.
[0058] To minimize a height of module 100 , components may be disposed on the inside surfaces of both bottom circuit board 101 and top circuit board 102 . Preferably, components disposed on bottom circuit board 101 and top circuit board 102 are staggered to avoid having two large components on corresponding locations of bottom circuit board 101 and top circuit board 102 . If one tall component 113 is disposed on bottom circuit board 101 , and a second tall component is disposed on top circuit board 102 immediately above the tall component on bottom circuit board 101 , then the height of module 100 may become larger than necessary. Thus, it may be beneficial to place a tall component 113 on bottom circuit board 101 , and place a short component in the corresponding location on top circuit board 102 above the tall component. Likewise, a tall component may be placed on top circuit board 102 , and a short component may be placed on bottom circuit board 101 below the tall component on top circuit board 102 . Further, if a relatively tall component is placed on either bottom circuit board 101 or top circuit board 102 , then the corresponding location on the other circuit board may be left empty to minimize the overall height of module 100 . This staggering of components is advantageous, because a minimum height of the module is kept as small as physically possible depending on the largest component that may be disposed on bottom circuit board 101 or top circuit board 102 .
[0059] FIG. 4 is an isometric view of a 3×2 enclosure 400 adapted to house a plurality of modules 100 in an exemplary embodiment of the invention. Enclosure 400 comprises a bottom plate 401 and a plurality of spacers 403 . More specifically, enclosure 400 comprises twelve spacers 403 . Spacers 403 are arranged in a grid pattern, with each spacer 403 being equally spaced apart in an X-direction and a Y-direction of the grid pattern. Each module 100 has corresponding cut-outs 111 to fit within spacers 403 . Further, the size of each edge of bottom circuit board 101 and top circuit board 102 may be integer multiples of a base value. The base value is equal to a distance between the centers of two of the spacers 403 . Thus, modules 100 may be placed at any location of enclosure 400 and fit within any four spacers 403 . Connector strips 408 on circuit substrate 406 electrically couple adjacent modules 100 . Circuit plane 407 on circuit substrate 406 distributes ground to modules 100 . Thermal contact pad 405 passes through circuit substrate 406 to thermally couple bottom plate 401 to modules 100 . Holes 404 in spaces 403 accommodate fasteners (not shown) to affix top plate 402 to bottom plate 401 and to compress modules 100 with connector strips 408 and ground plane 407 . Enclosure 400 is adapted to house a total of six square modules 100 .
[0060] FIG. 5 is an isometric view of a 3×2 enclosure 400 showing the inside surface of top plate 402 and circuit substrate 506 . Connector strips 508 on circuit substrate 506 electrically couple adjacent modules 100 . Circuit plane 507 on circuit substrate 506 distributes power to modules 100 . Thermal contact pad 505 passes through circuit substrate 506 to thermally couple top plate 501 to modules 100 .
[0061] FIG. 6 is a top view of a 3×3 enclosure 600 adapted to house a plurality of modules 100 in an exemplary embodiment of the invention. As illustrated, enclosure 600 includes sixteen spacers 403 , and is adapted to house nine square modules 100 . However, if each edge of a module 100 is an integer multiple of a base value, modules do not need to be square shaped, but rather, may be any type of parallelepiped, or could even be other shapes, such as L-shaped or U-shaped. For example, an L-shaped module may comprise three or more 1×1 modules, and a U-shaped module may comprise five or more 1×1 modules. Exemplary dimensions of a 1×1 square module 100 are 25.6 mm×25.6 mm, with a height of 3.2 mm. Exemplary dimensions of cut-outs 111 A and 111 B of a 1×1 square module 100 have a 2 mm radius. Thus, a spacer 403 may have a 4 mm diameter to secure up to four 1×1 modules in place.
[0062] As illustrated in FIG. 6 , module 602 is a 1×2 module (e.g., is twice the length of module 100 , but the same width as module 100 ). Thus, module 602 may be 25.6 mm by 51.2 mm. Module 602 includes six cut-outs, one on each corner of module 602 , and two cut-outs 603 in the middle along the longest edge of module 602 .
[0063] Module 604 is a 2×2 module (e.g., is twice the length and twice the width of module 100 ). Thus, module 604 may be 51.2 mm by 51.2 mm. Module 604 includes nine cut-outs, four on each corner of module 604 , one cut-out 605 in the center of module 604 , and one cut-out 606 in the middle of each side of module 604 .
[0064] Spacers 403 have been described as arranged in a grid pattern, where each spacer 403 is spaced equally apart from other spacers 403 in both an X-direction and a Y-direction of the grid pattern. However, design criteria may dictate that some spacers 403 are not needed in the grid pattern. For example, a space in an enclosure may be selected to hold a module which is larger than a 1×1 module. Therefore, in some embodiments, a portion of the spacers 403 may be omitted from the grid pattern. For example, two adjoining spacers 403 may be placed two base value units of length apart, while other spacers 403 are placed one base value unit of length apart. This permits the utilization of the standard grid pattern, while accommodating large modules which do not require cut-outs to be placed in the middle of the component.
[0065] FIG. 7 is an isometric view of a multi-layered enclosure 700 adapted to house a plurality of layers of modules 100 in an exemplary embodiment of the invention. Enclosure 700 comprises a bottom plate 701 , and a plurality of spacers 403 coupled to bottom plate 701 . Each spacer 403 is twice the height of a module 100 . A first layer of modules 100 may be placed horizontally on bottom plate 701 . A second layer of modules 100 may be vertically stacked atop the first layer of modules 100 . Stacked modules 100 are connected by outside contacts 109 . A top plate 402 is placed above the second layer of modules 100 to secure modules 100 in a Z-direction. Multi-layered enclosure 700 allows six 1×1 modules 100 to be horizontally configured in an X-direction and a Y-direction of multi-layer enclosure 700 . Additionally, multi-layered enclosure 700 allows for two layers of modules 100 to be stacked together, allowing up to twelve 1×1 modules 100 to be enclosed in multi-layered enclosure 700 . However, any number of layers may be stacked, and any number of modules 100 may be horizontally placed on each layer depending on desired design criteria. Additionally, as described in FIG. 6 , different sized modules having edges which are integer multiples of a base value may be horizontally and vertically configured in multi-layered enclosure 700 .
[0066] FIG. 8 is a side view of circuit boards 101 and 102 of module 100 being connected by inside contacts 107 of connector 103 . Circuit board 102 is clamped between spring leaf outside contacts 109 A and spring leaf inside contacts 107 of connector 103 causing electrical coupling of outside contacts 109 A to outside contact pads 110 A and electrical coupling of inside contacts 107 with inside contact pads 108 A. Circuit board 101 is clamped between spring leaf outside contacts 109 B and spring leaf inside contacts 107 of connector 103 causing electrical coupling of outside contacts 109 B to contact pads 110 B and electrical coupling of inside contacts 107 with contact pads 108 A. Thus circuit board 101 is electrically coupled to circuit board 102 through contacts 107 .
[0067] Module 100 is electrically coupled to other modules using outside spring leaf contacts. FIG. 9 is a side view of the connection between two stacked modules in an exemplary embodiment of the invention. More specifically, the left portion of FIG. 9 illustrates two modules prior to coupling, and the right portion of FIG. 9 illustrates two modules coupled together. FIG. 10 is a side view of the connection between two modules laid side-by-side in the same plane. More specifically, the left portion of FIG. 10 illustrates two modules prior to coupling, and the right portion of FIG. 10 illustrates two modules coupled together. The side-by-side coupling uses connector strips 1002 on enclosure base 1001 to couple with contacts 109 B on the two modules.
[0068] As illustrated in FIGS. 1-3 , module 100 comprises thirteen bottom spring leaf outside contacts 109 B and thirteen top spring leaf outside contacts 109 A. In the described embodiment, these thirteen pairs of connectors comprise a power contact, two ground contacts, two control signal contacts, and eight data signal contacts for transferring 8-bit data. However, any number of contacts and configurations may be used depending on desired design criteria.
[0069] FIG. 11 is an isometric view of connector 103 showing inside spring leaf contacts 107 in an exemplary embodiment of the invention. Each inside contact matingly engages with inside contact pads on the circuit boards 101 and 102 of a module 100
[0070] FIG. 12 is an isometric view of connector 103 showing outside spring leaf contacts 109 A and 109 B in an exemplary embodiment of the invention.
[0071] FIG. 13 is an isometric view of insulator material 1101 separating the top outside contacts, the bottom outside contacts, and the inside contacts in an exemplary embodiment of the invention. Insulator material 1101 may run substantially the length of top circuit board 102 (i.e., run the length of the edge between two cut-outs 111 B). Insulator material 1101 has a plurality of slots 1301 adapted to electrically isolate each of the plurality of bottom outside contacts 109 B. More specifically, insulator material 1101 may have thirteen slots 1301 to physically and electrically isolate each bottom outside contacts 109 B. Additionally, insulator material 1101 has a plurality of slots 1303 adapted to electrically isolate each of the plurality of top outside contacts 109 A. More specifically, insulator material 1101 may have thirteen slots 1303 to physically and electrically isolate each top outside contacts 109 A. Additionally, insulator material 1101 has a plurality of slots 1302 adapted to electrically isolate each of the plurality of inside contacts 107 . More specifically, insulator material 1101 may have twenty-five slots 1302 to physically and electrically isolate each inside contacts 107 .
[0072] It may become necessary to couple an enclosure of modules 100 , or one or more modules 100 to an external device. For example, if an enclosure comprises the components of a handheld computer, then it may become necessary to couple the modules of the enclosure to a printer, input device, network connection, external storage device, etc. An exemplary embodiment of the invention comprises provisions for coupling one or more modules 100 to an external device.
[0073] FIG. 14 is a view of a module enclosure 1400 connected to an external device 1401 in an exemplary embodiment of the invention. Module enclosure 1400 may house any number of modules 100 , including a plurality of layers of modules 100 . Module enclosure 1400 may also be one of a plurality of module enclosures which are vertically stacked atop one another. Module enclosure 1400 may further comprise a case for an electronic device, e.g., a handheld computer, mobile telephone, etc. External device 1401 may be a printer, external storage system, network connection, or any other type of external device connected to a computer, handheld computer or electronic device.
[0074] FIG. 15 is a flow chart of a method 1500 for forming a module in an exemplary embodiment of the invention. The steps of method 1500 will be described in reference to the module of FIGS. 1-3 . The steps of method 1500 are not all inclusive, and may include other steps not shown for the sake of brevity.
[0075] Step 1502 comprises providing a first circuit board 101 having a component surface. Step 1504 comprises providing a second circuit board 102 having a component surface, the component surface of the second circuit board disposed facing the component surface of the first circuit board. Next, components on positioned on the component surface of the first circuit board and the component surface of the second circuit board to minimize un-utilized space between the first circuit board and the second circuit board. There is a first height between the first circuit board and the second circuit board. In step 1506 , a first component is positioned on the component surface of the first circuit board. The first component has a second height which is less than the first height. In step 1508 , a remaining height is determined based on the first height minus the second height. In step 1510 , a second component is positioned on the first surface of the second circuit board, with the second component having a third height which is less than or equal to the remaining height. This results in a module with minimal un-utilized space, while providing a module which may be constructed of a uniform height as other modules.
[0076] Although specific embodiments were described herein, the scope of the invention is not limited to those specific embodiments. The scope of the invention is defined by the following claims and any equivalents therein.
|
A method and apparatus are provided for the interconnection of multiple circuit boards within a device. A module is provided which comprises multiple circuit boards interconnected with a plurality of connectors. Modules may be interconnected to other modules using the same connectors. Circuit components are disposed on inner surfaces of the circuit boards of the module. Multiple circuit boards and modules are interconnected by contacts that do not require soldering, that permit the circuit boards and modules to be removably coupled to each other by the contacts, and that permit circuit boards to be positioned by a spaced amount that results in a small spacing between circuit boards. Enclosures are also provided, which allow modules to be configured and secured in both a horizontal and vertical direction. Thus, modules may be interconnected to other modules on each side, as well as interconnected to other modules stacked above or below the module.
| 7
|
FIELD OF THE INVENTION
[0001] The present invention relates generally to the field of fixation mechanisms for facet joint stabilization.
BACKGROUND
[0002] The vertebrae in a patient's spinal column are linked to one another by the intervertebral disc and the facet joints. Each vertebra has four facet joint surfaces: a pair of articulating surfaces located on the left side, and a pair of articulating surfaces located on the right side. Each facet joint is a synovial joint consisting of two overlapping articulating surfaces, an superior articular process of one vertebra and an inferior articular process of the vertebra directly above it. The biomechanical function of each facet joint is to guide and limit the motion of the spinal motion segment. These functions can be disrupted by disc or bone degeneration, dislocation, fracture, injury, trauma-induced instability, osteoarthritis, and surgery. Such damage to the facet joint can result in pain, a misaligned spine, impinged nerves, and loss of mobility. In certain cases, partial or complete immobilization of one or more facet joints by intervertebral stabilization is desirable to alleviate the patient's symptoms.
[0003] Intervertebral stabilization is designed to prevent or restrict relative motion between the vertebrae of the spine. One method of intervertebral stabilization is to directly fasten one or both of the facet joints in a spinal motion segment together, thereby limiting intervertebral motion. From a surgical perspective, the facet joint is more easily accessible than the vertebral body or the pedicles, thus reducing operative time, decreasing blood loss, decreasing incision size, reducing incidence of reoperation, and decreasing the risk of potential deleterious effects on nearby anatomic structures, including the spinal cord.
[0004] In order to provide effective fixation of the facet joint, a fixation device should create compression between the two articular processes. The compression, which causes or enhances immobilization of the joint by encouraging stability through the joint, should be maintained over a significant length of time. In addition, the device must work to prevent loosening of the device. Because the facet joint is designed to be a mobile, weight-bearing joint, forces will continue to be transmitted through the joint after the implantation of a fixation device. Without a specific way to prevent loosening of the device, loosening will likely occur as a result of the micromotion caused by such forces. Once the device has loosened, the device may begin to protrude or regress from the bone, causing pain, joint damage, or danger to the surrounding tissues.
[0005] Surgeons have used various fixation devices, including bone screw assemblies, to immobilize the facet joint. Examples of facet fixation devices currently used to stabilize the spine include trans-lamina facet screws and trans-facet pedicle screws. The previously proposed facet fixation devices, however, have presented significant shortcomings. Both trans-lamina facet screws and trans-facet pedicle screws can be difficult to surgically place, have long trajectories, and may deleteriously interfere with the local anatomy once implanted. In addition, though a standard fully threaded bone screw may be sufficient for adjoining two bone surfaces, a fully threaded screw may not be capable of creating a desirable amount of compression between two bone surfaces. Any compression generated between the bone surfaces would be limited to the compressive forces generated by the screw threads themselves. Further, a bone screw may loosen overtime. When a screw is over-tightened and threads are stripped within the bone, or when threads strip over time as a result of micromotion, the compressive force between the facet joint surfaces will diminish and loosening will likely occur. To prevent loosening, still other bone screws are designed such that a portion of the screw expands within the bone after the device is implanted. However, the expansion of the device within bone generates great stress on the bone, making this device ill-suited for use in the relatively small bones of the facet joint. In an attempt to simultaneously maintain compression and prevent loosening, nut-and-bolt type assemblies have been presented as a method of facet joint immobilization. In this type of assembly, a threaded bolt or screw is passed through the facet joint and a nut with mating threads is placed around the distal end of the bolt or screw. Though this approach is successful in maintaining compression and preventing loosening, this approach mandates a surgical procedure that is more invasive than desired because the nut must be introduced to the back side of the facet joint.
[0006] Thus, though various systems in the prior art have attempted to achieve effective facet joint fixation, none of the prior art systems enable facet joint fixation through a minimally invasive, compressive, and stable facet fixation device. Accordingly, there is a need for instrumentation and techniques that facilitate the safe and effective stabilization of facet joints. Therefore, it would be advantageous to provide a system and method of facet joint fixation that can be implanted simply, accurately, and quickly, while providing suitable stabilization to the facet joint.
[0007] The device and methods disclosed herein overcome one or more of the shortcomings discussed above and/or in the prior art.
SUMMARY
[0008] The present invention relates to devices and methods for accomplishing bone fixation, and more particularly in some embodiments, to devices and methods for fixation of spinal facet joints.
[0009] In one exemplary aspect, the present disclosure is directed to a spinal implant extendable across a facet joint to aid in fixation of the facet joint. The implant may comprise an elongate connecting member sized to extend across a facet joint, a bone allograft, and a locking member. The elongate connecting member may have a distal end comprising a distal bone anchor. The bone allograft may be sized for placement in a bore formed through the facet joint and configured to be placed about the elongate connecting member. The locking member may include a longitudinal bore sized to receive the elongate connecting member, and may have an unlocked condition permitting movement relative the elongate connecting member and a locked condition rigidly fixing the locking member in place on the elongate connecting member. The locking member may be configured to cooperate with the distal bone anchor to compress the facet joint, and the locking member may be configured to lock the spinal implant across the facet joint.
[0010] In another exemplary aspect, the present disclosure is directed to a spinal implant for fixation of a facet joint. The implant may comprise an elongate connecting member sized to extend across a facet joint, a bone allograft, a locking member, and a stabilization member. The elongate connecting member may have a distal end comprising a distal bone anchor. The bone allograft may be sized for placement in a bore formed through the facet joint and configured to be placed about the elongate connecting member. The locking member may include a longitudinal bore sized to receive the elongate connecting member, and may have an unlocked condition permitting movement relative the elongate connector and a locked condition rigidly fixing the locking member in place on the elongate connecting member. The locking member may be configured to cooperate with the distal bone anchor to compress the facet joint, and the locking member may be configured to lock the spinal implant across the facet joint. The stabilization member may include a bone contacting surface and an opposing surface, and the stabilization member may be configured to seat the locking member on the opposing surface. The stabilization member may include a hole extending therethrough sized to receive the elongate connecting member, wherein the stabilization member slides over a portion of the elongate connecting member such that the portion extends through the hole.
[0011] In another exemplary aspect, the present disclosure is directed to a method for fixation of a facet joint, the facet joint having a superior articular process and an inferior articular process. The method may comprise: forming a drill hole through the facet joint, inserting an elongate connecting member having a distal anchor into the facet joint and advancing the elongate connecting member and the distal anchor into the facet joint until the elongate connecting member spans the facet joint, drilling a well circumferentially around the elongate connector member, packing the well with a bone allograft, sliding a locking member over the elongate connector member such that locking member contacts the inferior articular process, and compressing the locking member around the elongate connector member to stabilize the facet joint.
[0012] Further aspects, forms, embodiments, objects, features, benefits, and advantages of the present invention shall become apparent from the detailed drawings and descriptions provided herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
[0014] FIG. 1 is a lateral view of a portion of the lumbar spine with a portion of a facet joint in cross-section, showing a spinal implant disposed within the facet joint in accordance with a first embodiment of the present disclosure.
[0015] FIG. 2 is a perspective view of the spinal implant shown in FIG. 1 .
[0016] FIG. 3 is a highly simplified drawing of a portion of a vertebral arch, showing a delivery cannula positioned through the skin and against the inferior articular process of a facet joint.
[0017] FIG. 4 is a lateral, partial cross-sectional view of a spinal motion segment showing an elongate connecting member and a distal anchor of the spinal implant of FIG. 1 inserted into a facet joint.
[0018] FIG. 5 is a lateral, partial cross-sectional view of a spinal motion segment showing a cannulated drill positioned around the elongate connecting member and against the inferior articular process.
[0019] FIG. 6 is a lateral, partial cross-sectional view of a spinal motion segment showing a drilled intrafacet cavity.
[0020] FIG. 7 is a lateral, partial cross-sectional view of a spinal motion segment showing a bone allograft within the intrafacet cavity.
[0021] FIG. 8 is a lateral, partial cross-sectional view of a spinal motion segment showing insertion of a locking member around the elongate connecting member.
[0022] FIG. 9 is a lateral view of a spinal motion segment showing a spinal implant inserted into and fixed against the facet joint.
[0023] FIG. 10 is a perspective view of a spinal implant in accordance with a second embodiment of the present disclosure.
[0024] FIG. 11 a is a highly simplified, partial cross-sectional view of the first embodiment of the spinal implant in its final, expanded state.
[0025] FIG. 11 b is a highly simplified, partial cross-sectional view of the second embodiment of the spinal implant in its final, expanded state.
DETAILED DESCRIPTION
[0026] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments, or examples, illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.
[0027] This disclosure describes implants and methods for stabilizing a facet joint. The implants described herein are structurally designed to span the facet joint and, due to the placement of a bone allograft across the joint, create stable fixation through fusion. The implants fasten one or both of the facet joints in a spinal motion segment together, thereby limiting intervertebral motion and alleviating the patient's symptoms.
[0028] FIG. 1 illustrates an implant 10 according to an exemplary embodiment of the present invention for fixing, stabilizing, and/or immobilizing a joint. The spinal implant 10 is shown implanted within a facet joint formed by a superior articular process 12 of one vertebra 14 and an inferior articular process 16 of the vertebra 18 immediately above. The implant 10 can also be utilized to stabilize other joints besides the facet joint. The implant 10 includes an elongate connecting member 20 , a distal anchor 22 , a bone allograft 24 , and a locking member 26 . FIG. 1 shows the implant 10 inserted into the facet joint such that the distal anchor 22 protrudes outside and lateral to the superior articular process 12 while the elongate connecting member 20 and the bone allograft 24 remain within the bony tissue of the facet joint. Accordingly, the elongate connecting member 20 is disposed through both the superior articular process 12 and the inferior articular process 16 through a drill hole formed through both the processes 12 , 16 . The bone allograft 24 promotes bone fusion between the superior articular process 12 and the inferior articular process 16 . The locking member 26 , which is sized to have a wider diameter than the drill hole, is positioned flush against the exterior surface of the inferior articular process 16 . The implant 10 provides stabilization and immobilization of the facet joint formed by the processes 12 , 16 through compressive forces applied by the distal anchor 22 and the locking member 26 . In addition, the amount of compressive force applied by the implant 10 can vary with the position of the locked locking member 26 relative to the distal anchor 22 . The closer to the distal anchor 22 that the locking member 26 is locked, the greater the compressive forces exerted on the facet joint.
[0029] FIG. 2 illustrates the exemplary implant 10 in an expanded state. As indicated above, the implant 10 includes the elongate connecting member 20 , the distal anchor 22 , the bone allograft 24 , and the locking member 26 . In the embodiment shown in FIG. 2 , the elongate connecting member 20 is approximately cylindrical and configured to be received within the prepared drill hole through the superior articular process 12 and the inferior articular process 16 of the facet joint. The elongate connecting member 20 is made of a flexible and durable biocompatible material configured as a cable. For example, the elongate connecting member 20 can be constructed of surgical stainless steel, titanium, cobalt-chromium alloy, Nitinol, ultra-high molecular weight polyethylene, poly(tetraflouroethylene) or poly(tetraflouroethene) (PTFE), polyethylene terephthalate (PET), or any other biocompatible material as is known in the art of medical device manufacture. Alternatively, the elongate connecting member could be configured as a wire, a braid, or a rod. Optionally, the elongate connecting member 20 can be constructed of a radiolucent material, such as polyaryletheretherketone (PEEK) or the like, such that it can be medically imaged and visualized. Further, the elongate connecting member 20 can be treated with growth factors, stem cells, or any other device coating known in the art, to be selected based on the desired outcome of the procedure. In some embodiments, the elongate connecting member 20 is substantially taut and rigid, while in other embodiments, the elongate connecting member 20 can flex. In these embodiments, the elongate connecting member 20 is flexible enough to be positioned within a prepared drill hole formed through the facet joint, but is rigid enough to immobilize the superior articular process 12 and the inferior articular process 16 with respect to one another. In some examples, the elongate connecting member 20 is configured to flex or bend laterally, but is configured to substantially resist axial elongation.
[0030] As shown in FIG. 2 , the elongate connecting member 20 extends from a proximal portion 30 to a distal portion 28 which is attached to the distal anchor 22 . In some embodiments, the distal portion 28 may extend to integrally form the distal anchor 22 . The elongate connecting member 20 is of a length suitable to fit through the facet joint from the exterior surface of the inferior articular process 16 to the exterior surface of the superior articular process 12 . The elongate connecting member 20 can include a variety of lengths and dimensions as required for different spinal morphologies.
[0031] The distal anchor 22 may be configured to have an unexpanded configuration or state and an expanded configuration or state. In the unexpanded configuration or state, the distal anchor 22 may be sized and configured to pass through a pilot hole formed through the facet joint. In the expanded configuration or state, the distal anchor 22 may be sized and configured as a hook-like structure to anchor the implant 10 and resist axial regression through the pilot hole. In the embodiment pictured in FIG. 2 , the distal anchor 22 in an expanded state has an arrowhead-like configuration including an exterior surface 32 , at least two flanges 34 , and bone-engaging surfaces 36 . In the example shown in FIG. 2 , the flanges 34 are moveable between two positions: an insertion position or unexpanded state wherein the flanges 34 are approximately parallel with a longitudinal axis 37 of the elongate connecting member 20 , and a bone-engaging position or expanded state wherein the flanges 34 are angled with respect to the longitudinal axis 37 of the elongate connecting member 20 . More specifically, in the insertion, unexpanded state, the flanges 34 are positioned generally flush against the distal portion 28 of the connecting member 20 . Upon emerging from the prepared drill hole through the facet joint, the flanges 34 flare away from the connecting member 20 and the distal anchor 22 assumes a bone-engaging, expanded state. At least a portion of the bone-engaging surfaces 36 of the distal anchor 22 then engages the exterior surface of the superior articular process 12 . The material composition of the distal anchor 22 resiliently biases the flanges 34 toward the bone-engaging, expanded state. In this example, the distal anchor 22 is made of a flexible, surgical-grade material that is configured to allow extensive short-term deformation without permanent deformation, cracks, tears, or other breakage. In particular, in this example, the distal anchor is made of a shape memory alloy having a memory shape in the expanded configuration. In other embodiments, the distal anchor 22 is formed of an elastic material allowing the flanges 34 to elastically deform to an unexpanded state to fit through the drilled hole, and spring back to an expanded state when the distal anchor 22 advances clear of the hole. In the embodiment pictured in FIG. 2 , the exterior surface 32 is smooth. However, in other embodiments, the exterior surface 32 can include features that engage bony tissue. The features can resemble screw threads or any other configuration that would interface with and provide friction with bony tissue. The features can include structures of various sizes, dimensions, shapes, and configurations.
[0032] As the embodiment pictured in FIG. 2 shows, the implant 10 also includes a bone allograft 24 . The bone allograft 24 has a generally cylindrical shape having generally planar and circular ends and a generally cylindrical sidewall. The bone allograft 24 includes a centrally disposed and cylindrically shaped bore 38 . The diameter of bore 38 is slightly larger than the diameter of the elongate connecting member 20 , such that the elongate connecting member 20 is slidable within the bore 38 . In some embodiments, the bone allograft 24 is composed of a bone dowel. In other embodiments, the bone allograft 24 is composed of loose allograft material, such that the allograft material surrounds the elongate connecting member 20 when the implant 10 is in final position across the facet joint.
[0033] As the embodiment pictured in FIG. 2 shows, the implant 10 also includes a locking member 26 . The locking member 26 is approximately cylindrical, and has a proximal surface 40 , a bone-engaging surface 42 , and a centrally disposed and cylindrically shaped longitudinal bore 44 . The proximal surface 40 can be flat or rounded or have a variety of configurations compatible with the adjacent anatomical tissue. In the example shown, the proximal surface 40 is rounded to avoid edges that may introduce additional tissue trauma. The bone-engaging surface 42 can be flat or curved or have a variety of configurations compatible with the exterior surface of the inferior articular process 16 . In some embodiments, the locking member 26 can be approximately spherical. In some embodiments, the locking member 26 can be non-continuous in that a longitudinal slot comprising the length of the locking member 26 extends from the sidewall 45 to the bore 44 .
[0034] The implant 10 pictured in FIG. 2 has features 46 that extend perpendicularly from the bone-engaging surface 42 . Here, the features 46 are triangular protrusions capable of stabilizing the locking member 26 against the exterior surface of the inferior articular process 16 . Pressure can be exerted on the locking member 26 to embed the features 46 in the surface of the inferior articular process 16 . The locking member 26 may include any number of features 46 . The features 46 can include structures of various sizes, dimensions, shapes, and configurations. Further, a single locking member 26 can include features 46 of different sizes, dimensions, shapes, and configurations. In addition, the locking member 26 can include any orientation of features 46 on the bone-engaging surface 42 . For example, the features can be equally spaced around the circumference of the bone-engaging surface, thereby allowing the locking member 26 to engage the inferior articular process 16 and adding to the overall stability of the implant 10 . In other embodiments, the features 46 can extend at acute or obtuse angles from the bone-engaging surface 42 .
[0035] The bore 44 extends longitudinally through the locking member 26 from the proximal surface 40 to the bone-engaging surface 42 . The diameter of bore 38 is slightly larger than the diameter of the elongate connecting member 20 , such that the elongate connecting member 20 is slidable within the bore 44 . The inner surface of the bore 44 can be textured such that the bore 44 of locking member 26 grips the connecting member 20 .
[0036] The locking member 26 is formed of a deformable and durable surgical-grade material. For example, the locking member 26 can be constructed of surgical stainless steel, titanium, cobalt-chromium alloy, Nitinol, ultra-high molecular weight polyethylene, poly(tetraflouroethylene) or poly(tetraflouroethene) (PTFE), polyethylene terephthalate (PET), or any other deformable biocompatible material as is known in the art of medical device manufacture. Optionally, the locking member 26 can be constructed of a radiolucent material, such as polyaryletheretherketone (PEEK) or the like, such that it can be medically imaged and visualized. In one example, after the implant 10 is positioned across the facet joint, the locking member 26 is fixedly secured to the elongate connecting member 20 by crimping the locking member 26 to the connecting member 20 such that the desired amount of compression is achieved across the facet joint.
[0037] The implant 10 is utilized to stabilize and/or immobilize the facet joint by limiting the motion between the superior articular process 12 and the inferior articular process 16 . The implant 10 is assembled and implanted in the following manner, described with reference to FIGS. 3-9 . In FIGS. 3-9 , the vertebrae are depicted in dashed lines to indicate that the drawings illustrate the two-dimensional positional relationship of the implant 10 relative to the three-dimensional vertebral structures.
[0038] First, access to the facet joint is gained through any suitable surgical technique using any suitable device. Advantageously, referring to FIG. 3 , the implant 10 can be implanted through a minimally invasive surgical procedure involving a single midline incision 50 through the skin S over the spinous process 52 of the vertebra 18 superior to the target facet joint. In FIG. 3 , a custom delivery cannula 54 (that is part of a delivery device) is shown resting against the inferior articular process 16 after being inserted through a midline incision 50 . The cannula 54 is operable to route the elongate connecting member 20 , the distal anchor 22 , the bone allograft 24 , and the locking member 26 into correct positions relative to the facet joint. The cannula 54 is made of a surgical-grade material, and in particular stainless steel, though other materials are suitable. The cannula 54 is cylindrical with an longitudinal passage extending along its entire length from a proximal end 56 to a distal end 58 . The diameter of the cannula 54 is larger than the diameter of the implant 10 in an expanded configuration such that the implant 10 in an expanded configuration is slidable within the passage of the cannula 54 . Further, the diameter of the cannula 54 is such that the bone allograft 24 and the locking member 26 are slidable within the passage of the cannula 54 .
[0039] The distal end 58 of the delivery cannula 54 includes at least one docking feature 60 that extends in the same plane as the longitudinal passage of the cannula 54 . The docking feature 60 is capable of stabilizing the cannula 54 to an anatomical structure. For example, the docking feature 60 can serve as a docking point on which the cannula 54 may securely rest against or penetrate the inferior articular process 16 , thereby preventing the cannula 54 from slipping from the surface of the inferior articular process 16 during the implantation procedure. Pressure can be exerted on the delivery cannula 54 to temporarily embed the feature in the surface of the inferior articular process 16 . The delivery cannula 54 may include any number of such docking features 60 . The docking features 60 can include structures of various sizes, dimensions, shapes, and configurations. Further, a single cannula 54 can include docking features 60 of different sizes, dimensions, shapes, and configurations. In addition, the cannula 54 can include any orientation of such docking features 60 on the bone contacting surface. For example, the docking features 60 can be equally spaced around the circumference of the distal end of the cannula 54 . In some embodiments, the docking feature 60 may be angled away from the side of the cannula 54 .
[0040] A hole is then formed through the facet joint by any of various mechanisms as are known in the art. An exemplary mechanism for forming a hole through the facet joint involves directing a drill through the cannula 54 , positioning the drill against the exterior surface of the inferior articular process 16 , and drilling a continuous hole through both the inferior articular process 16 and the superior articular process 12 . The hole is formed in a desired location to provide optimal stabilization/immobilization of the facet joint. The hole is dimensioned to allow passage of the elongate connecting member 20 and the distal anchor 22 . Other mechanisms for forming the hole are also contemplated. For example, an 11-gauge needle could be used to “punch” a hole through the facet joint. After the hole is prepared, the drill or other instrument used to form the hole is withdrawn from the cannula 54 .
[0041] Referring to FIG. 4 , the elongate connecting member 20 and the distal anchor 22 are passed through the cannula 54 to be inserted into the prepared drill hole in an insertion, unexpanded state. In this example, when in the insertion, unexpanded state, the flanges 34 of the distal anchor 22 are positioned generally flush against the distal portion 28 of the connecting member 20 such that the connecting member 20 and the folded distal anchor 22 possess a smaller diameter than the diameter of the prepared drill hole. The connecting member 20 is then pushed forward through the prepared drill hole until the distal anchor 22 emerges through the superior articular process 12 . Upon emerging from the prepared drill hole, the flanges 34 of the distal anchor 22 flare away from the connecting member 20 and the distal anchor 22 assumes a bone-engaging, expanded state. More specifically, once the distal anchor 22 has passed all the way through the inferior articular process 16 , across any gap between the inferior articular process and the superior articular process, and all the way through the superior articular process 12 , the flanges 34 of the distal anchor 22 flare out from their insertion, unexpanded position—in substantial alignment with the longitudinal axis 37 of the elongate connecting member 20 —into their bone-engaging, expanded position at an angle with the longitudinal axis 37 of the elongate connecting member 20 , as shown in FIG. 2 . At least a portion of the bone-engaging surfaces 36 of the distal anchor 22 then engages the exterior surface of the superior articular process 12 . Once in position, the elongate connecting member 20 and the distal anchor 22 function to properly align and hold the superior articular process 12 against the inferior articular process 16 . It is worth noting that although the elongate connecting member 20 is shown with a limited length, in some embodiments, the elongate connecting member 20 has an overall length greater than the length of the cannula 54 . Accordingly, the elongate connecting member 20 may extend out the proximal end of the cannula 54 for easy access by the surgeon.
[0042] Referring to FIG. 5 , a cannulated drill 70 is advanced through the cannula 54 and around the proximal portion 30 of the elongate connecting member 20 until it rests against the surface of the inferior articular process 16 . Using the cannulated drill, an intrafacet cavity 76 is drilled around the elongate connecting member 20 all the way through the inferior articular process 16 , and partially into the superior articular process 12 such that the intrafacet cavity 76 extends to a depth in the range of, for example, one third to one half of the thickness of the superior articular process 12 , as shown in FIG. 6 . In some embodiments, the cannulated drill 70 is configured to debride the cartilaginous tissue between the inferior articular process 16 and the superior articular process 12 , thereby “bloodying” the intrafacet cavity 76 and creating a favorable environment for the bone allograft 24 . In some embodiments, the cannulated drill 70 includes a suction channel, which is operatively arranged to remove excess bone and tissue debris created by the drilling process. After the intrafacet cavity 76 is prepared, the cannulated drill 70 is withdrawn from the cannula 54 .
[0043] Referring to FIG. 6 , the intrafacet cavity 76 is shown extending all the way through the inferior articular process 16 and extending partially into the superior articular process 12 . The intrafacet cavity 76 is shaped and sized to accommodate the bone allograft 24 .
[0044] Referring to FIG. 7 , the bone allograft 24 is passed through the cannula 54 and slid over the proximal portion 30 of the elongate connecting member 20 . In particular, the bore 38 of the bone allograft 24 is positioned to encircle the proximal portion 30 of the elongate connecting member 20 , and then the bone allograft 24 is slid down the elongate connecting member to rest in the intrafacet cavity 76 . The bone allograft 24 promotes bone fusion between the superior articular process 12 and the inferior articular process 16 .
[0045] Referring to FIG. 8 , after insertion of the bone allograft 24 into the intrafacet cavity 76 , the locking member 26 is passed through the cannula 54 and slid over the proximal portion 30 of the elongate connecting member 20 . In particular, the bore 44 of the locking member 26 is positioned to encircle the proximal portion 30 of the elongate connecting member 20 , and then the locking member 26 is slid down the elongate connecting member to rest against the exterior surface of the inferior articular process 16 . The features 46 on the bone-engaging surface 42 of the locking member 26 engage with the exterior surface of the inferior articular process 16 such that the locking member is stabilized against the exterior surface of the inferior articular process 16 . Pressure can be exerted on the locking member 26 to embed the features 46 in the surface of the inferior articular process 16 . Due to the diameter of the locking member 26 , which is greater than the diameter of the intrafacet cavity 76 into which the bone allograft 24 is inserted, the locking member 26 provides a mechanism by which the bone allograft is isolated within the facet joint and the implant 10 is fixed within the facet joint, thereby stabilizing the facet joint. Tension is provided by pulling the proximal portion 30 of the elongate connecting member 20 through the locking member 26 . As tension is provided, the locking member 26 is pushed against the inferior articular process 16 to achieve the desired alignment and compression of the facet joint. Specifically, the proximal portion 30 of the elongate connecting member 20 is pulled in the longitudinal axis 37 in a direction away from the distal anchor 22 while the locking member 26 is simultaneously pushed against the inferior articular process such that the desired alignment and compression of the superior articular process 12 against the inferior articular process 16 is achieved. After the desired alignment and amount of compression are realized, the locking member 26 is fixedly secured to the elongate connecting member 20 by crimping the locking member 26 to the connecting member 20 such that the desired alignment and amount of compression is maintained across the facet joint.
[0046] The implant 10 provides stabilization and immobilization of the facet joint formed by the processes 12 , 16 through compressive forces applied by the distal anchor 22 and the locking member 26 . In addition, the amount of compressive force applied by the implant 10 can vary with the position of the locked locking member 26 relative to the distal anchor 22 . The closer to the distal anchor 22 that the locking member 26 is locked, the greater the compressive forces exerted on the facet joint.
[0047] FIG. 9 shows the spinal implant 10 inserted into and fixed against the facet joint. The proximal portion 30 of the elongate connecting member 20 is shown extending proximally through the locking member 26 . The surgeon clips the proximal portion 30 of the elongate connecting member 20 such that the elongate connecting member 20 no longer substantially extends past the proximal surface 40 of the locking member 26 , as shown in FIG. 11 a . FIG. 11 a shows the spinal implant 10 spanning across the inferior articular process 16 and the superior articular process 12 in its final, expanded state.
[0048] FIG. 10 illustrates a second embodiment of the spinal implant 10 in its expanded state. In the embodiment illustrated in FIG. 10 , the implant 10 includes the elongate connecting member 20 , the distal anchor 22 , the bone allograft 24 , a locking member 78 , and a stabilization member 80 . The locking member 78 is substantially similar in shape and size to the locking member 26 , but the locking member 78 includes a distal surface configured to interface with a proximal surface of the stabilization member 80 . In this embodiment, the stabilization member 80 is configured as a gimbaled washer. As such, the stabilization member 80 includes a proximal surface 84 configured to seat the locking member 78 . The stabilization member 80 also includes a bone contacting surface 82 being configured to engage the exterior surface of the inferior articular process 16 . The stabilization member 80 includes a hole 86 extending from the bone contacting surface 82 to the proximal surface 84 sized to encircle the elongate connecting member 20 . The diameter of the hole 86 is less than the diameter of the locking member 78 , thereby allowing the stabilization member 80 to seat the substantially hemispherical bottom portion of the locking member 78 on the concave proximal surface 84 . As such, the hemispherical bottom portion of the locking member 78 being seated in the stabilization member 80 enables polyaxial motion of the locking member 78 relative to the stabilization member 80 . Providing such a polyaxial coupling allows greater versatility of the implant 10 because the stabilization member 80 and the locking member 78 can adjust to anatomical structures of various shapes, thereby allowing for a more personalized and precise fit of the implant 10 .
[0049] The stabilization member 80 includes at least one feature 88 extending perpendicularly from the bone contacting surface 82 capable of stabilizing the stabilization member 80 against the inferior articular process 16 . The features 88 can include structures of various sizes, dimensions, shapes, and configurations. Further, a single stabilization member 80 can include features 88 of different sizes, dimensions, shapes, and configurations. For example, the features 88 can be configured as any one of spikes, teeth, serrations, grooves, or ridges. Referring to FIG. 10 , the stabilization member 80 includes a plurality of features 88 configured as triangular protrusions adapted to pierce the outer portion of the inferior articular process 16 . The stabilization member 80 may include any number of such features. In addition, the stabilization member 80 can include any orientation of such features 88 on the bone contacting surface 82 . For example, the features 88 can be equally spaced around the circumference of the bone-contacting surface 82 , thereby allowing the stabilization member 80 to engage the inferior articular process 16 and adding to the overall stability of the implant 10 . In other embodiments, the features 88 can extend at acute or obtuse angles from the bone contacting surface 82 .
[0050] FIG. 11 b shows the second embodiment of the spinal implant 10 , as illustrated in FIG. 10 , spanning across the inferior articular process 16 and the superior articular process 12 in its final, expanded state.
[0051] The devices, systems, and methods described herein provide an improved and more accurate system of facet joint stabilization. Applicants note that the procedures disclosed herein are merely exemplary and that the systems and methods disclosed herein may be utilized for numerous other medical processes and procedures. Although several selected embodiments have been illustrated and described in detail, it will be understood that they are exemplary, and that a variety of substitutions and alterations are possible without departing from the spirit and scope of the present invention, as defined by the following claims.
|
A spinal implant extendable across a facet joint to aid in fixation of the facet joint includes an elongate connecting member, a bone allograft, and a locking member. The elongate connecting member is sized to extend across a facet joint and includes a distal bone anchor. The bone allograft is sized for placement in a bore formed through the facet joint and configured to be placed about the elongate connecting member. The locking member includes a longitudinal bore sized to receive the elongate connecting member, and the locking member has an unlocked condition permitting movement relative the elongate connecting member and a locked condition rigidly fixing the locking member in place on the elongate connecting member. The locking member is configured to cooperate with the distal bone anchor to compress the facet joint, and the locking member is configured to lock the spinal implant across the facet joint.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of Korean Patent Application No.2003-89362, filed on Dec. 10, 2003 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a handover method and apparatus in a mobile Internet protocol (IP) version 6 (IPv6) environment, and more particularly, to handover methods and handover apparatuses for a fast-moving terminal in a mobile IPv6 environment.
[0004] 2. Description of the Related Art
[0005] Recently, wireless network access has been a field of increasing interest because it allows nodes to move at a reasonable speed during communications and accessing a network.
[0006] FIG. 1 is a reference diagram to explain the structure of the prior art IPv6 wireless network. Mobile IPv6 is designed to manage movement of a mobile node among IPv6 networks.
[0007] Referring to FIG. 1 , when a mobile node 100 is in its home network determined as a cell of an access router (AR), old AR 110 , the mobile node 100 communicates with a correspondent node, as an IPv6 node. However, when the mobile node 100 moves to another subnet determined as a cell of a new AR 120 , the home address of the mobile node 100 is not valid any more and packets transmitted by the correspondent node are transferred to the previous home network. Accordingly, the mobile node 100 should obtain care-of address (CoA) that is a new valid address in the subnet being visited by the mobile node 100 and should register this new care-of address in its home agent 130 and the correspondent node. Thus connecting the home address of the mobile node and the current care-of address is referred to as “binding”.
[0008] The moving of a mobile node among access points belonging to an identical subnet is managed by layer 2 (L2) protocol. Meanwhile, if a mobile node is connected to an access point (AP) in another subnet, the IPv6 address of the mobile node is not valid any more, and this kind of moving should be managed by L3 protocol. L3 protocol provides a seamless connection, called L3 handover, to an IPv6 mobile node when the mobile node moves from one wireless point to another wireless point in another subnet.
[0009] The handover procedure will now be explained briefly. A mobile node analyzes router advertisement which is sent periodically by an access router, and thus detects whether or not the mobile node has moved to a new subnet. The mobile node may ask the access router to send a router advertisement, by sending a router solicitation message. Information contained in this router advertisement helps the mobile node generate a new care-of address. The mobile node performs address generation based on given information. First, address automatic formation is performed with a link local address and a network prefix included in router advertisement, and then redundant address detection is performed with this address to verify that this address is unique.
[0010] However, the mobile node is unable to receive an IP packet at the new point unless the handover is finished. This time comprises a time taken to detect a new prefix in a new subnet, a time taken to set a new care-of address, and a time taken to notify the new location of the mobile node to a correspondent node and the home agent, and is referred to as ‘handover latency’.
[0011] Actually, this handover latency may be too long in real time multimedia applications. In many cases, this handover latency may greatly degrade the quality of IPv6 streams of a mobile node.
[0012] A concept of fast handover has been introduced to reduce the handover latency and packet losses due to this handover of a mobile node.
[0013] Since the drawbacks are caused by the fact that the conventional handover method performs handover by using only layer 3 information, the fast handover method is intended to more actively perform a handover process by using layer 2 information. In order to optimize the moving of a mobile node, fast handover performs handover in two methods: one is an anticipated handover using L2 trigger, and the other is a tunnel-based handover.
[0014] In the anticipated handover method, the fact that a mobile node has moved to a new network is not recognized by receiving a router advertisement signal, but by receiving a signal (L2 trigger) in layer 2 at a moment when the mobile node moves into a new network. By doing so, changes in the network situation can be recognized a little earlier such that the handover can be performed.
[0015] FIG. 2 is a reference diagram to explain “anticipated handover” among related high speed handover methods.
[0016] Referring to FIG. 2 , in the anticipated handover method, a mobile node 200 or a current access router 230 receives the L2 trigger indicating that the mobile node 200 is to perform the L2 handover. This trigger contains information allowing identification of a target access router 240 .
[0017] If a mobile node 200 receives the L2 trigger, the mobile node 200 begins the handover, and asks a current access router 230 for a fast handover. Then, the current access router 230 transmits an IPv6 address available in a new subnet to the mobile node 200 and a target access router 240 .
[0018] Then, the target access router 240 verifies whether or not the received address is available in the subnet and if available, transmits the verification result to the current access router 230 . If the address is available, the current access router 230 transmits to the mobile node 200 an authentication message indicating that the address can be used.
[0019] When the mobile node establishes a connection to the new access point 220 , the mobile node can immediately use a new CoA as the source address of an outbound packet and transmit a binding update to the home agent and a correspondent node.
[0020] Tunnel-based handover enables routers of an existing network and a new network to form a channel to each other, and to process packets through this channel during handover generating a CoA. This method delays generation of a CoA and utilizes the existing CoA till a new communication connection is established, such that packet losses can be reduced.
[0021] FIG. 3 is a reference diagram to explain “tunnel-based handover” among related art high speed handover methods. Referring to FIG. 3 , in the tunnel-based handover method, when a mobile node 300 moves from a current access router AR 0 310 to a new access router AR 1 320 , the mobile node 300 delays setting a new CoA. Accordingly, the mobile node 300 performs only the L2 handover and continues to use the previous CoA in the new subnet. In addition, the mobile node 300 does not need to exchange any packet. Two access routers AR 0 310 and AR 1 320 set a bidirectional tunnel from the L2 trigger without interaction with the mobile node 300 . Packets transmitted to the mobile node arrive at the previous subnet and are forwarded to the new access router AR 1 320 by the previous access router AR 0 310 . Packets transmitted by the mobile node follow the reverse path from the new access router AR 1 320 to the previous access router AR 0 310 .
[0022] Then, the mobile node generates and registers a CoA while performing communications. The use of the L2 trigger enables an access router to detect the moving of a mobile node without a need to transmit any packet. Interface with a third access router AR 2 330 , as the mobile mode 300 moves, is carried out in a similar manner.
[0023] Meanwhile, as the use of IPv6 is being diversified, it is expected that IPv6 terminals will be installed in high-speed modes of transportation such as automobiles and high-speed trains. Terminals moving fast usually have directivity, by which those that are moving travel in a predetermined direction, thus, the motion can be predicted in such special situations.
[0024] Fast handover according to the two concepts of anticipated handover and tunnel-based handover as described above can solve many of the problems of the conventional mobile IPv6 handover process. However, it cannot solve all the problems and in particular, in a terminal moving at a high speed, there are additional problems.
[0025] For example, in the case of anticipated handover, the effect is maximized when a mobile node begins handover at an L2 trigger time point and already finishes the handover process when the mobile node cannot receive a packet from the previous network and has to use a new network. In this case, the handover process should begin earlier than the L2 trigger time point. When the speed of the mobile node is very high, there may be such a case where a mobile node has already moved to another network when handover is finished. Accordingly, a solution for a fast-moving terminal which needs faster beginning of handover has not been provided.
[0026] Also in the case of tunnel-based handover, in a situation where there are many fast-moving terminals, the load to form a channel becomes very large in each router. In addition, because a router should manage channel information for each mobile terminal, the load to a router becomes more serious on a freeway or high-speed train where fast-moving terminals are crowded. Accordingly, in order to provide a smooth handover function to a fast-moving terminal, a handover process which has an earlier handover beginning time, and puts less of a load on a router is needed.
[0027] Also, since major applications include VoIP and multimedia streaming, a real-time transmission concept reducing packet losses as much as possible while a packet can arrive at a receiver at a time when the transmitter and receiver want is also needed for operations of a variety of applications.
SUMMARY OF THE INVENTION
[0028] In an aspect of the present invention, a handover method and handover apparatus which can reduce handover latency and packet losses for a fast-moving terminal in a mobile IPv6 environment are provided.
[0029] According to an aspect of the present invention, there is provided a handover method including requesting handover to an access router based on the moving speed of a mobile node.
[0030] In an aspect, the requesting handover operation includes measuring the moving speed of the mobile node, or obtaining the moving speed of the mobile node by calculating the moving speed of the mobile node based on time information of the time when the mobile node is connected to the IP of routers visited by the mobile node.
[0031] In an aspect, the requesting handover also includes determining a handover mode for a fast-moving terminal which begins a handover operation before an L2 trigger of the mobile node based on the obtained moving speed data; and if the handover mode for a fast-moving terminal is determined, generating and transmitting a care-of address (CoA) request message before the L2 trigger of the mobile node.
[0032] According to another aspect of the present invention, there is provided a handover method provided to an access router including performing tunneling so that access routers on a path to a destination access router participate in tunneling, based on the destination access router information of a mobile node.
[0033] In an aspect, performing tunneling includes receiving a CoA request message including the destination access router information from the mobile node; transmitting a CoA request message having the destination access router as a destination; receiving a CoA response message from an intermediate access router which receives the CoA request message; and transmitting a duplicated packet of a packet directed to the mobile node, to the intermediate access router.
[0034] According to another aspect of the present invention, there is provided a handover method provided to an access router including a mobile node predicting an access router to be connected by the mobile node, based on information on access routers visited by the mobile node, and by using the predicted access router, performing handover.
[0035] In an aspect, the handover method further including receiving a CoA message including information on access routers visited by the mobile node, from the mobile node; predicting an access router to be connected by the mobile node, based on the access router information included in the CoA message; transmitting a CoA request message having the predicted access router as a destination; receiving a CoA response message from the predicted access router which receives the CoA request message; and transmitting a duplicated packet of a packet directed to the mobile node, to the predicted access router.
[0036] In an aspect, the handover method further including receiving a CoA message including information on access routers visited by the mobile node, from an access router; predicting a next access router to be connected by the mobile node, based on the moving speed information of the mobile node included in the CoA message; transmitting a CoA request message having the predicted access router as a destination; receiving a CoA response message from the predicted access router which receives the CoA request message; and transmitting a duplicated packet of a packet directed to the mobile node, to the predicted access router.
[0037] According to another aspect of the present invention, there is provided a handover method including at a first time point of an L2 trigger, receiving a CoA request message, which is received from a mobile node by a previous access router, from the previous access router, generating a CoA, and receiving a duplicated packet directed to the mobile node from the previous access router using the generated CoA; and at a second time point of the L2 trigger, transmitting the duplicated packet using the CoA, in response to a release request from the mobile node.
[0038] In an aspect of the handover method, the first time point of the L2 trigger indicates a time when the strength of an L2 signal corresponding to a cell which the mobile node belongs to currently goes down below a lower threshold and at the same time the strength of an L2 signal corresponding to a next cell goes up above an upper threshold, and the second time point of the L2 trigger indicates a time when the strength of an L2 signal corresponding to a cell which the mobile node belongs to currently goes down below an upper threshold and at the same time the strength of an L2 signal corresponding to a next cell goes up above a lower threshold.
[0039] According to a further aspect of the present invention, there is provided a handover apparatus provided to a mobile node including a handover booster which requests handover to an access router based on the moving speed of the mobile node.
[0040] According to an aspect of the present invention the handover apparatus, the handover booster includes a moving speed calculation/measurement unit which calculates or measures the moving speed of the mobile node.
[0041] According to an aspect of the present invention, the handover apparatus, the moving speed calculation/measurement unit includes a moving speed measurement unit which has a sensor for measuring the moving speed of the mobile node.
[0042] According to an aspect of the present invention the handover apparatus, the moving speed calculation/measurement unit includes a moving speed calculation unit which calculates the moving speed of the mobile node based on time information on the time when the mobile node is connected to the IP of routers visited by the mobile node.
[0043] According to an aspect of the present invention the handover apparatus the handover booster includes a handover mode determination unit which determines a handover mode for a fast-moving terminal which begins a handover operation before L2 trigger of the mobile node based on the moving speed data output by the moving speed calculation/measurement unit; and a handover request unit which if the handover mode determination unit determines the handover mode for a fast-moving terminal, generates and transmits a CoA request message before L2 trigger of the mobile node.
[0044] In an aspect of the present invention CoA request message includes the moving speed of the mobile node and information providing the destination of the mobile node.
[0045] According to an additional aspect of the present invention, there is provided handover apparatus provided to an access router including a pre-handover agent which performs tunneling so that access routers on a path to a destination access router participate in tunneling, based on the destination access router information of a mobile node.
[0046] In an aspect of the present invention, in the handover apparatus, a duplicated packet directed to the mobile node is transmitted to the access routers participating in the tunneling.
[0047] According to an additional aspect of the present invention, there is provided a handover apparatus provided to an access router comprising a pre-handover agent which predicts an access router to be connected by the mobile node, based on information on access routers visited by the mobile node, and requests handover to the predicted access router.
BRIEF DESCRIPTION OF THE DRAWINGS
[0048] The above aspects and/or advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings of which:
[0049] FIG. 1 is a reference diagram to explain the structure of the conventional IPv6 wireless network;
[0050] FIG. 2 is a reference diagram to explain “anticipated handover” among conventional high speed handover methods;
[0051] FIG. 3 is a reference diagram to explain “tunnel based handover” among conventional high speed handover methods;
[0052] FIG. 4 is a reference diagram to explain a pre-handover method for a terminal moving at a high speed according to an embodiment the present invention;
[0053] FIG. 5 is a block diagram showing an example of the structure of communication devices performing a pre-handover method according to an embodiment the present invention;
[0054] FIG. 6 is a block diagram showing an example of a detailed structure of the handover booster shown in FIG. 5 according to an embodiment of the present invention;
[0055] FIG. 7A is a block diagram showing an embodiment of a detailed structure of the moving speed calculation/measurement unit shown in FIG. 6 according to an embodiment of the present invention;
[0056] FIG. 7B is a block diagram showing another embodiment of a detailed structure of the moving speed calculation/measurement unit shown in FIG. 6 according an embodiment of to the present invention;
[0057] FIG. 8 is a reference diagram to explain a packet to which a handover message according to an embodiment the present invention is applied;
[0058] FIG. 9 is a diagram of the structure of a handover message according to an embodiment of the present invention;
[0059] FIG. 10 is a block diagram showing an example of a detailed structure of pre-handover agent of an access router shown in FIG. 5 ;
[0060] FIG. 11 is a reference diagram to explain router information of the access routers shown in FIG. 5 ;
[0061] FIG. 12 is a flowchart of a pre-handover operation method according to an embodiment of the present invention;
[0062] FIG. 13 is a flowchart of the operations performed by a tunneling operation method according to an embodiment of the present invention;
[0063] FIG. 14 is a diagram of a message flow according to an embodiment of the tunneling operation method of FIG. 13 ;
[0064] FIG. 15 is a diagram of a message flow according to another embodiment of the tunneling operation method of FIG. 13 ; and
[0065] FIG. 16 is a diagram of a message flow according to another embodiment of a tunneling operation method.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0066] Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below to explain the present invention by referring to the figures.
[0067] In an aspect of the present invention, the care-of address (CoA) establishing process from automatic formation to duplicated address detection (DAD), which takes a significant amount of time in a handover process, is performed in advance so that immediately after an L3 handover occurs, a mobile node can use a new CoA.
[0068] In addition, considering that fast-moving terminals usually have predetermined directivity, a bicasting technique which is used mainly for layer 2 in the conventional applications is expanded by applying a layer 3 tunneling technique in an aspect of the present invention. That is, in order to establish a route to a destination based on the directivity of a fast-moving mobile node, the speed of a terminal is measured by a time for connection between access routers and the fast-moving terminal so that even when the speed of the terminal increases, layer 3 handover can be performed in an appropriate time.
[0069] FIG. 4 is a reference diagram to explain a handover method for a fast-moving terminal according to an embodiment of the present invention. Referring to FIG. 4 , access router (AR) AR 0 410 belongs to the IP0 address network (cell 0), AR 1 420 belongs to the IP1 address network (cell 1), and AR 2 430 belongs to the IP2 address network (cell 2).
[0070] When an upper threshold and lower threshold are determined for an L2 signal, both an L2 trigger 1 and an L2 trigger 2 are used. The L2 trigger1 indicates a time point when a current L2 signal corresponding to a current cell goes down below the upper threshold and at the same time a next L2 signal corresponding to the next cell goes up over the lower threshold. The L2 trigger2 indicates a time point when the current L2 signal corresponding to the current cell goes down below the lower threshold and at the same time the next L2 signal corresponding to the next cell goes up over the upper threshold.
[0071] A mobile node 400 stores connection information whenever the mobile node 400 is connected to an access router (AR) in layer 2, and calculates the speed using the connection information. Meanwhile, when the mobile node 400 is connected to a new AR in layer 3, the speed calculation is performed in the same manner as in layer 2 and the speed of the mobile node 400 is calculated. At the L2 trigger 2 time point, a CoA to be used in the next cell is requested by the access router.
[0072] If the L2 trigger 1 occurs in cell 0, the mobile node 400 transmits a release request message to AR 0 410 . After receiving this message, AR 0 410 transmits a release message to AR 1 420 , and AR 1 420 begins to release packets by a new CoA of the mobile node 400 , which are being received, by the network.
[0073] Next, if the L2 trigger 2 occurs between cell 0 and cell 1, the mobile node 400 transmits a CoA request message and receives a new CoA from AR 1 420 , and by receiving packets on the new CoA, completes the handover process between cell 0 and cell 1. At this time, AR 1 420 which receives the CoA request message by the mobile node 400 according to the L2 trigger 2, analyzes the CoA request message and transmits the CoA request message to the access router AR 2 430 which the mobile node is to be connected to next, so that the AR 2 430 can generate a new CoA in advance. AR 2 performs a job to generate the new CoA for the mobile node 400 .
[0074] FIG. 5 is a block diagram showing an example of the structure of communication devices performing a handover method for a fast-moving terminal according an embodiment of to the present invention. Referring to FIG. 5 , the communication devices performing the handover method for a fast-moving terminal includes a mobile node 510 , an access point 520 and an access router 530 .
[0075] The mobile node 510 comprises a mobile IP stack 511 , a handover booster 512 , and an RF signal transmission and reception unit 513 . The mobile IP stack 511 stores mobile IP information, and the RF signal transmission and reception unit 513 communicates a signal with the access point 520 . The handover booster 512 calculates the speed of a mobile terminal and according to the speed information performs a handover request. The handover booster will be explained in detail later.
[0076] The access point 520 comprises an RF generator 521 which is provided so as to transmit and receive a signal between the access router 530 and the mobile node 510 .
[0077] The access router 530 comprises a pre-handover agent 531 , a mobile IP high-speed handover module 532 , and a router module 533 . The mobile IP high-speed handover module 532 performs the conventional high-speed handover operation, and the router module 533 provides the router function of an access router. The pre-handover agent 531 provides fast layer 3 handover function for a fast-moving terminal. The pre-handover agent 531 will be explained in detail later.
[0078] The handover operation for a fast-moving terminal according to the structure of communication devices shown in FIG. 5 will now be explained. Based on the moving speed of the mobile node 510 and destination information, the handover booster 512 of the mobile node 510 transmits a CoA request message to the access router 530 through the access point 520 at an L2 trigger 2 time point.
[0079] The pre-handover agent 531 of the access router 530 responds to the mobile node 510 with a CoA which the pre-handover agent 531 has already generated in the previous operation. Also, in order that the mobile node 510 can receive the CoA directly from an access router to be connected next, the pre-handover agent 531 analyzes the received CoA request message, determines the destination of the mobile node 510 and others, and requests the pre-handover agent 551 of another access router 550 to generate a CoA. If a CoA response from the pre-handover agent 551 is received, the pre-handover agent 531 transmits duplicated data of packet data directed to the mobile node 510 with the CoA as the destination address, to the pre-handover agent 551 .
[0080] If the mobile node 510 moves and then makes a release request to the access router 530 at an L2 trigger 1 time point, the access router 550 transmits the received duplicated packet data to the mobile node 510 through the access point 540 by using the already generated CoA.
[0081] FIG. 6 is a block diagram showing an example of a detailed structure of the handover booster shown in FIG. 5 according to an embodiment of the present invention. Referring to FIG. 6 , the handover booster 512 comprises a moving speed calculation/measurement unit 610 , a handover mode determination unit 620 , and a handover request unit 630 .
[0082] The moving speed calculation/measurement unit 610 calculates or measures the speed of a mobile node 510 , based on layer 2 and layer 3 handover information, and continuously stores and manages the information in a database (not shown).
[0083] The handover mode determination unit 620 receives information on the speed of a mobile node 510 calculated by the moving speed calculation/measurement unit 610 , and based on this, determines a handover mode. For example, if the speed exceeds a predetermined threshold, a handover mode for a fast-moving terminal is determined and if the speed does not exceed the predetermined threshold, a handover mode for an ordinary mobile terminal can be determined.
[0084] The handover request unit 630 receives the determined mode from the handover mode determination unit 620 , and if it is the handover mode for a fast-moving terminal, generates and transmits a handover message used in a handover method for a fast-moving terminal, and if it is the handover mode for an ordinary mobile terminal, generates and transmits the conventional handover message. The handover message used in the handover method for a fast-moving terminal according to an embodiment of the present invention will be explained in detail referring to FIGS. 8 and 9 .
[0085] FIG. 7A is a block diagram showing an embodiment of a detailed structure of the moving speed calculation/measurement unit shown in FIG. 6 according to an embodiment of the present invention.
[0086] Referring to FIG. 7A , the moving speed calculation/measurement unit 610 comprises a router history information 611 and a moving speed measurement unit 612 . The router history information 611 contains the layer 2 and layer 3 handover information described above. Layer 3 handover information includes information on routers visited previously by a mobile node, that is, each router IP and the timestamp which is speed information when the mobile node is connected to the router. Layer 2 handover information includes information on access points visited by the mobile node till now, that is, each access point IP and the timestamp which is speed information when the mobile node is connected to the access point. This router history information 611 comprises history information of about five routers including the router immediately before the current router connected to the mobile node.
[0087] The moving speed measurement unit 612 has a sensor measuring the moving speed of a mobile node and measures the moving speed. With this sensor, it is not needed to separately calculate the moving speed by using the router history information.
[0088] FIG. 7B is a block diagram showing another embodiment of a detailed structure of the moving speed calculation/measurement unit shown in FIG. 6 according to an embodiment of the present invention. Referring to FIG. 7B , the moving speed calculation/measurement unit 610 comprises a router history information 611 and a moving speed calculation unit 613 .
[0089] The router history information 611 is the same as described above in referring to FIG. 7A . The moving speed calculation unit 613 calculates a speed based on each distance between routers and timestamps included in the router history information 611 . In addition, by comparing a speed change using the layer 2 handover information with a speed change using the layer 3 handover information, the moving speed calculation unit 613 can finally modify the speed of a mobile node.
[0090] FIG. 8 is a reference diagram to explain the structure of a packet header of a handover message for a fast-moving terminal according to an embodiment of the present invention. A handover message comprises a packet header and contents.
[0091] The packet header complies with the standard IPv6 header structure and uses a hop by hop option header. The structure of a hop by hop extended header is as shown in FIG. 8 .
[0092] Next Header 1 is used to recognize a next header, Hdr Ext Len 2 indicates the length of an extended header, Padding 3 is a padding area to match the number of bits, and Options 4 defines an option.
[0093] The option field may use a router warning option defined in the standard. According to the standard, in Value 6 of the router warning option indicated by reference number 5, because 0, 1, 2 are already bound to other purposes, values from 3 to 65535 can be used. In order to be used for aspects of the present invention, the value of Value 6 can use any one of the values from 3 to 65535 excluding 0, 1, and 2.
[0094] Both a mobile node and a router form the packet headers of the structure shown in FIG. 8 to generate the handover message packet.
[0095] FIG. 9 shows the structure of the contents of a handover message according to an embodiment of the present invention. Referring to FIG. 9 , the contents of a handover message include a length 10 , a command 11 , a speed 12 , a reservation 13 , a mode 14 , an original device IP 15 , a destination IP 16 , and router ID & timestamps 17 through 21 .
[0096] The length 10 indicates with 4 bits the length of the entire handover message.
[0097] The command 11 indicates a packet for a situation determined by two bits. Bits of 00 indicate a CoA request message transmitted by a mobile node to an access router, bits of 01 indicate a CoA request message transmitted by the access router to another access router in a different network, bits of 10 indicate a CoA response message transmitted to the access router from another access router in a different network, and bits of 11 indicate a CoA response message transmitted by the access router to the mobile node. For a CoA response message, CoA information is further included in a message, though not shown in FIG. 9 .
[0098] The speed 12 indicates the speed of the mobile node with 10 bits.
[0099] The reservation 13 is a 14-bit space made to be empty for other purposes and also has a function of padding to make a 32-bit string.
[0100] The mode 14 indicates with 2 bits whether or not there is a final destination. For example, bits of 01 indicate that there is a final destination and 00 can indicate that an intermediate destination should be estimated continuously. When there is a predetermined destination, such as a case when a mobile node uses a freeway, a high-speed train, or an automatic path guide system using a global positioning system (GPS), an indication that destination information is included is written in the mode 14 field of a CoA request message, and final destination information is written in the destination IP 16 field of the handover request message.
[0101] The original device IP 15 indicates the initial IP of a mobile node with 128 bits, and is used by access routers to recognize the mobile node regardless of CoA changes.
[0102] The destination IP 16 indicates the final destination IP by 128 bits and, if there is no final destination, can be filled with zeros.
[0103] Each router ID & timestamp 17 through 21 indicates history information of an access router visited by the mobile node with 64 bits, and includes the router ID and timestamp. For example, in the case where there is no predetermined destination such as in an ordinary trunk road, the handover booster 512 of the mobile node 510 writes information on the router path visited by the mobile node 510 till in the router ID & timestamps 17 through 21 field of the handover request message.
[0104] FIG. 10 is a block diagram showing an example of a detailed structure of the pre-handover agent of the access router shown in FIG. 5 according to an embodiment of the present invention. Referring to FIG. 10 , the pre-handover agent 531 comprises a handover message analysis unit 561 , a router prediction unit 562 , a handover message generation/transmission unit 563 , and a duplicated packet processing unit 564 .
[0105] The handover message analysis unit 561 receives a handover message from the mobile node 510 or another access router 550 , and analyzes the contents of the handover message. The handover message includes a CoA request message which requests a response on a CoA after generating the CoA, a CoA response message which responds to the CoA request message after generating another CoA as a response to the CoA request message, and a release request message which requests an access router to transmit duplicated packet data stored in the access router 530 .
[0106] If the handover message is a CoA request message from the mobile node 510 , the handover message analysis unit 561 secures an L3 tunneling channel by communicating with pre-handover agents 551 of other access routers 550 . In this case, the handover message generation/transmission unit 563 generates and transmits a CoA request message to a destination router.
[0107] If the handover message analysis unit 561 receives a CoA request message from another access router 550 , the handover message generation/transmission unit 563 transmits the received CoA message to a next access router (not shown) so that the received CoA message can be forwarded to the destination. In addition, by performing CoA autoconfiguration and duplicated address detection (DAD), a predetermined module (not shown) of the pre-handover agent 531 secures an address that can be used immediately when the mobile node 510 enters into an area managed by the pre-handover agent 531 .
[0108] If the handover message analysis unit 561 receives a CoA response message from another access router 550 , the handover message generation/transmission unit 563 transmits the received CoA response message to the mobile node 510 , and by using the received CoA response message, the duplicated packet processing unit 564 transmits packets that are likely to be lost during the handover process, through the L3 tunneling channel established between access router 510 and 550 , respectively. Meanwhile, this duplicated packet processing unit 564 receives a duplicated packet from another access router and stores it, and if the mobile node 510 transmits a release request by an L2 trigger 2, the duplicated packet processing unit 564 converts the packet into a packet having a new CoA of the mobile node 510 as a target address, and transmits the converted packet to the mobile node 510 . A release request message is transmitted by the mobile node 510 to a current access router 530 , and the current message transmits the release request to the next access router 550 .
[0109] A CoA response message transmitted by an access router to the mobile node includes a newly generated CoA to be used by the mobile node. A CoA response message transmitted by an access router to another access router includes a CoA newly generated for the mobile node for receiving a duplicated packet.
[0110] If the received CoA request message includes the final destination, the handover message generation/transmission unit 563 generates a CoA request message to send to the final destination and transmits the CoA request message in a hop by hop method.
[0111] If a CoA request message includes only intermediate destination information, the router prediction unit 562 predicts a next access router to be connected to the mobile node by using the intermediate destination information. In addition, the router prediction unit 562 can predict two or more access routers to be connected by the mobile node according to the speed information of the mobile node included in the handover request message.
[0112] By using router information thus predicted by the router prediction unit 562 , the handover request message generation/transmission unit 563 can generate a CoA request message with this predicted router as a destination and transmit.
[0113] An example of a method for the router prediction unit 562 predicting a next router will now be explained referring to FIG. 11 . FIG. 11 is a reference diagram to explain router information which the access router shown in FIG. 5 uses according to an embodiment of the present invention.
[0114] Location information of a router can be given by allocating a unique ID for each access router, and in router distribution allocation by area as shown in FIG. 11 , Arabic numbers are arranged in the horizontal axis and the English alphabet letters are arranged in the vertical axis.
[0115] When an area to which an access router is allocated is divided in a 5-staged depth, an example of an ID allocated to an access router can be B2C6A1H7U9. By arranging the router information in this manner, the directivity of a router can be determined only by information on routers visited by the mobile node and an access router that should be connected next can be estimated. Each ID with the corresponding IP address of the router is managed in a table.
[0116] FIG. 12 is a flowchart of the operations performed by a pre-handover operation method according to an embodiment of the present invention.
[0117] The operations shown in FIG. 12 includes an operation requesting a CoA to an access router to obtain the CoA in advance when it is determined that the mobile node moves at a high speed, according to the moving speed of the mobile node before L2 trigger.
[0118] First, the handover booster 512 of the mobile node 510 monitors the time taken for establishing connections with the visited access routers in operation 1201 , and calculates the moving speed of the mobile node 510 based on the monitored data in operation 1202 .
[0119] Next, the handover booster 512 determines a handover mode for a fast-moving terminal based on the calculated moving speed data in operation 1203 , and transmits a CoA request message to the access router 530 at the L2 trigger 2 time point in operation 1204 . In this CoA request message, final destination information, or visited intermediate operation access router information and moving speed information of the mobile node are inserted as described referring to FIG. 9 .
[0120] FIG. 13 is a flowchart of the operations performed by a tunneling operation method according to an embodiment of the present invention. The operations shown in FIG. 13 include a tunneling process between a current access router which receives a CoA request from the mobile node, and next routers.
[0121] Referring to FIG. 13 , a mobile node transmits a CoA request message to a current access router at the L2 trigger 2 time point in operation 1301 , the pre-handover agent 531 of the current access router 530 which receives a request message analyzes the received CoA request message to determine whether or not it is a CoA request message for a fast-moving terminal in operation 1302 .
[0122] If the result of the analysis indicates that it is a CoA request message for a fast-moving terminal, the pre-handover agent 531 transmits a CoA response message as a response to the CoA request message, to the mobile node 510 , by using a CoA which the pre-handover agent 531 has already generated in the previous operation.
[0123] Then, the pre-handover agent 531 determines whether or not destination information is included in the CoA request message in operation 1303 , and if it is not included, predicts a next access router based on intermediate router information included in the CoA request message in operation 1304 . Then, the pre-handover agent 531 transmits a CoA request to the predicted router 550 in operation 1305 , and the pre-handover agent 551 of the predicted router 550 receives this CoA request, generates a CoA, and responds to the request in operation 1306 .
[0124] If destination information is included in the CoA request message, the pre-handover agent 531 requests a CoA to the destination router by using the destination information in operation 1307 . In the case where a CoA is thus requested to the final destination router, all routers on the path to the destination router determine by the hop by hop option header that the mobile node will come, and generate a new CoA, and respond in operation 1308 .
[0125] The pre-handover agent 531 of the access router 530 which receives the CoA response transmits a duplicated packet of the packet directed to the mobile node in operation 1309 .
[0126] If the mobile node 510 moves and transmits a release request to the access router 550 at an L2 trigger 1 time point, the access router 550 which has already received and stored a duplicated packet in the previous operation transmits a duplicated packet to the mobile node 510 in operation 1310 .
[0127] Operations performing handover among the access routers are explained above referring to the flowcharts shown in FIGS. 12 and 13 A- 13 B, and more detailed handover operations will now be explained referring to FIGS. 14 through 16 .
[0128] A basic handover process when final destination information is not in a CoA request message is shown in FIG. 14 , a handover process in which two or more access routers are made to participate in tunneling for a fast-moving terminal regardless of an L2 trigger when there is no final destination information is shown in FIG. 15 , and a handover process when there is final destination information is shown in FIG. 16 .
[0129] FIG. 14 is a diagram of a message flow according to a tunneling operation method according to an embodiment of the present invention. Referring to FIG. 14 , a mobile node in the AR 0 area transmits a CoA request to AR 0 , which is a current access router at an L2 trigger 2 time point in operation 1401 . AR 0 which receives the request transmits a CoA response to the mobile node by using a CoA which AR 0 has already generated in the previous operation in operation 1402 .
[0130] The mobile node which receives the CoA response from AR 0 begins to be able to receive a duplicated packet and a new packet from AR 0 .
[0131] The AR 0 which receives the CoA request predicts a next access router because there is no final destination information, and transmits a new CoA request to AR 1 which is the predicted access router in operation 1403 . The new access router AR 1 which receives the new CoA request generates a new CoA and transmits a new CoA response to AR 0 in operation 1404 .
[0132] AR 0 which receives the new CoA response transmits a duplicated packet directed to the mobile node to AR 1 in operation 1405 .
[0133] Next, the mobile node moves and then transmits a release request to current access router AR 0 at an L2 trigger 1 time point in operation 1406 , and AR 0 which receives the request transfers this release request to AR 1 in operation 1407 . Then, AR 1 which receives this release request transmits a duplicated packet, which AR 1 received from AR 0 and stored previously, to the mobile node by using the generated CoA.
[0134] This process is performed when the mobile node is both in an AR 1 area and in an AR 2 area in the same manner.
[0135] FIG. 15 is a diagram of a message flow according to a tunneling operation method according to another embodiment of the present invention. Referring to FIG. 15 , a mobile node in the AR 0 area transmits a CoA request to AR 0 , which is a current access router at an L2 trigger 2 time point in operation 1501 . AR 0 which receives the request, first transmits a CoA response to the mobile node by using a CoA which AR 0 has already generated in the previous operation. The mobile node which receives the CoA response from AR 0 begins to be able to receive a duplicated packet and a new packet from AR 0 .
[0136] Then, AR 0 predicts a next access router because there is no final destination information in the CoA request received from the mobile node, and transmits another CoA request to AR 1 , which is the predicted access router, as a destination in operation 1503 . AR 1 which receives the CoA request from the AR 0 checks the speed field of the received CoA request message, and if it is determined that the speed is very high, again predicts another next access router and transmits a CoA request to the predicted access router AR 2 as a destination in operation 1504 .
[0137] AR 1 which receives the CoA request from AR 0 generates a new CoA and transmits a CoA response to AR 0 in operation 1505 . AR 2 which receives the CoA request from AR 1 generates a new CoA and transmits a CoA response to AR 1 in operation 1506 .
[0138] AR 0 which receives the CoA response transmits a duplicated packet directed to the mobile node to AR 1 in operation 1507 and AR 1 which receives the duplicated packet from AR 0 transmits the duplicated packet to AR 2 in operation 1508 .
[0139] Next, the mobile node transmits a release request to AR 0 which is a current access router at L2 trigger 1 time point in operation 1509 . AR 0 which receives the request transmits the release request to AR 1 in operation 1510 . Then, AR 1 transmits the duplicated packet, which AR 1 received from AR 0 and stored in the previous operation, to the mobile node.
[0140] Next, if the mobile node moves to the AR 1 area and transmits a CoA request to AR 1 at an L2 trigger 2 time point in operation 1511 , AR 1 transmits a CoA response to the mobile node, by using a CoA which AR 1 has already generated in the previous operation, in operation 1512 , and AR 1 transmits another CoA request to AR 2 in operations 1513 . AR 2 which receives the request transmits a CoA response to AR 1 by using an already generated CoA in operation 1514 .
[0141] Then, if the mobile node transmits a release request to AR 1 at an L2 trigger 1 time point in operation 1515 , AR 1 transmits the release request to AR 2 in operation 1516 , and AR 2 , which receives the release request, transmits a duplicated packet, which AR 2 received from AR 1 and stored previously, to the mobile node.
[0142] Next, if the mobile node moves to the AR 2 area and transmits a CoA request to AR 2 at an L2 trigger 1 time point in operation 1517 , AR 2 transmits a CoA response to the mobile node by using a CoA which AR 2 has already generated, in operation 1518 , and the mobile node which receives the response begins to be able to receive a duplicated packet and a new packet from AR 2 .
[0143] FIG. 16 is a diagram of a message flow according to a tunneling operation method according to another embodiment of the present invention. Referring to FIG. 16 , a mobile node in the AR 0 area transmits a CoA request with a specified access router as a final destination, to an access router at an L2 trigger 2 time point in operation 1601 . This CoA request is transmitted to the final destination access router through access routers on a path to the final destination access router, in a hop by hop method.
[0144] AR 0 , which receives the CoA request, transmits a CoA response which AR 0 has already generated in the previous operation to the mobile node in operation 1602 . If the mobile node thus receives the CoA response, the mobile node can receive a new packet as well as a duplicated packet from AR 0 .
[0145] AR 1 , which receives the CoA request, generates a first new CoA and transmits a first CoA response to AR 0 in operation 1603 and AR 2 , which receives the CoA request, generates a second new CoA and transmits a second CoA response to AR 1 in operation 1604 .
[0146] AR 0 , which receives the first CoA response, transmits a duplicated packet directed to the mobile node to AR 1 in operation 1605 and AR 1 , which receives the duplicated packet from AR 0 , transmits the duplicated packet to AR 2 in operation 1606 .
[0147] If the mobile node transmits a release request to AR 0 at an L2 trigger 1 time point in operation 1607 , AR 0 transmits this release request to AR 1 in operation 1608 , and if AR 1 receives the release request, AR 1 transmits a duplicated packet, which AR 1 received from AR 0 and stored previously, to the mobile node.
[0148] Next, if the mobile node moves to the AR 1 area and transmits a CoA request to AR 1 at an L2 trigger 2 time point in operation 1609 , AR 1 transmits a CoA response to the mobile node by using a CoA which AR 1 has already generated in the previous step, in step 1610 , and AR 1 transmits a CoA request to AR 2 in operation 1611 . AR 2 which receives the CoA request transmits a CoA response to AR 1 by using an already generated CoA in operation 1612 .
[0149] Then, if the mobile node transmits a release request to AR 1 at an L2 trigger 1 time point in operation 1613 , AR 1 transmits the request to AR 2 in operation 1614 , and AR 2 which receives this release request, transmits a duplicated packet which AR 2 received from AR 1 and stored previously, to the mobile node.
[0150] Next, if the mobile node moves to the AR 2 area and transmits a CoA request to AR 2 at an L2 trigger 1 time point in operation 1615 , AR 2 transmits a CoA response to the mobile node by using a CoA which AR 2 has already generated, in operation 1616 , and the mobile node which receives the response begins to be able to receive a duplicated packet and a new packet from AR 2 .
[0151] As described above, with aspects of the present invention, smooth service can be provided for real-time data transmission for a fast-moving terminal which will be a major application of IPv6 in the future. The methods described can be applied to all traffic of a fast-moving terminal and its advantage can be displayed more particularly in a user datagram protocol (UDP) packet in which real-time availability is more important. It is because a UDP packet does not receive an acknowledge packet such that even in a packet forwarding process using tunneling, that a smaller burden is put on a router, and the transmission mechanism is relatively simpler than that of TCP such that the packet processing in each router is easier.
[0152] The related art was a passive method by which when a router advertisement signal is received or an L2 trigger occurs, handover begins. Compared to this, the method of embodiments of the present invention performs active handover based on the directivity of a fast-moving terminal such that the method has an advantage that the mobile node itself that can know the state of the mobile node most accurately can actively lead the handover. Through this method, packet loss rate can be reduced to zero, and real-time applications such as VoIP and real-time streaming can be provided reasonably in mobile IPv6 environments.
[0153] In addition, in an aspect of the present invention, the method is implemented completely by installing an agent program formed by software in each mobile node and access router. More accurate service can also be provided by interoperating with a GPS or speed measuring system.
[0154] The invention can be realized as a computer-readable code written on a computer-readable recording medium. The computer-readable recording medium includes nearly all kinds of recording devices, in which data can be stored in a computer-readable manner. For example, the computer-readable recording medium includes ROM, RAM, CD-ROM, a magnetic tape, a floppy disk, an optical data storage, or a carrier wave (e.g., data transmission through the Internet). In addition, the computer-readable recording medium can be distributed over a plurality of computer systems connected to one another in a network so that data written thereon can be read by a computer in a decentralized manner. Functional programs, codes, and code segments necessary for realizing the present invention can be easily inferred from the prior art by one of ordinary skill in the art that the present invention pertains to.
[0155] Embodiments of the present invention are designed for a fast-moving terminal having predetermined directivity such as a vehicle using a freeway or a terminal in a high-speed train and does not have any problem in using it together with the conventional high-speed handover method.
[0156] Applications applying mobile IPv6 to vehicles together with home networks are expected to increase in the future, and applying the method and apparatus described above can sufficiently provide services demanded by service providers and users, for example, listening to the Internet radio broadcasting or viewing film in a high-speed train, periodically checking the state of a vehicle, and using the Internet phone.
|
Communication handover methods and apparatuses for use in an environment involving terminals having mobile nodes moving at a high speed. The handover method includes actively requesting handover to an access router based on the moving speed of a mobile node. The handover methods and apparatuses reduce handover latency and packet losses in a handover process of a terminal moving at a high speed.
| 7
|
BACKGROUND OF THE INVENTION
This invention relates to artificial baby feeding.
I believe that there is a considerable difference between a baby's actions in suckling at the breast and sucking liquid from the artificial teats used on baby's bottles. In the first action, there is largely a biting action followed by a swallowing action, whereas in the second, it is necessary for the baby to create a negative pressure in its mouth before liquid, e.g. milk, can be caused to be drawn from the bottle by sucking. Not only this, but the bottle must be removed from the baby's mouth on occasions to allow air to enter into the bottle to replace the milk taken from the bottle by the baby. This has caused considerable disadvantages in the past in that some babies, particularly weak babies, do not quickly learn the necessary sucking action and it is believed that there are other physiological disadvantages in the present artificial baby feeding techniques.
OBJECTS AND SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide baby feeding methods and/or apparatus which will obviate or minimize the foregoing disadvantages in a simple yet effective manner or which will at least provide the public with a useful choice.
Accordingly, in one aspect, the invention consists in artificial baby feeding apparatus for use with a container and a teat, said apparatus comprising a flow directing means positioned, in use, between the container and the teat and pressure equalizing means adapted to prevent material negative pressure in the container during use, the construction and arrangement being such that, in use, milk or other liquid food supplied to the teat from the container may be expressed from the teat by squeezing parts of the teat towards each other while the container is elevated above the teat, milk flowing into the teat through said one way flow directing means on the teat distending after each compression and said pressure equalizing means operating to maintain substantially the same pressure inside as outside said container, with said flow directing means restricting or preventing flow of liquid back from the teat into the container.
In a further aspect, the invention consists in artificial baby feeding apparatus for use with a container, said apparatus comprising a teat fitted in use to the container, a flow directing means positioned, in use, between the container and the teat and pressure equalizing means adapted to prevent material negative pressure in the container during use, the construction and arrangement being such that, in use, milk or other liquid food supplied to the teat from the container may be expressed from the teat by squeezing parts of the teat towards each other while the container is elevated above the teat, milk flowing into the teat through said one way flow directing means on the teat distending after each compression and said flow directing means restricting or preventing flow of liquid back from the teat into the container.
To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.
One preferred form of the invention and modifications thereof will now be described with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical diagrammatic part cross section of a baby's feeding bottle associated teat and including apparatus according to the invention,
FIG. 2 is a perspective view of a valve used in the invention, and,
FIG. 3 is a plan view of an alternative perforated diaphragm used in the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, in one form of the invention, apparatus for the artificial feeding of a baby from a container is constructed as follows. The container e.g. a bottle 1 for liquid food, for example, milk is constructed in the normal way, except that an opening 2 may be provided e.g. a slot 2 adjacent the bottle mouth and open to atmosphere so that air may be admitted into the container. This preferred way of admitting air will, however, be referred to later. The container is preferably provided with a screw top 3, with the top having an aperture 4 through which a teat 5 may be fitted so that the teat is sealed to the top of the container with the exception of the air opening through slot 2. The teat is preferably arranged to have a harder nipple 6 than an adjacent part 7 of the teat which is softer to conform to the softer part of the breast adjacent the nipple in nature. This may be effected by having a thinner cross section of flexible material e.g. rubber in the softer part than in the harder nipple part. It may also be effected by shaping the softer part e.g. to a toroidal or other suitable form. The part 7 is shown as of toroidal form in FIG. 1 separated by a neck 25 from a base 24 of the teat 5, and/or the teat may have stiffening ribs 8 and a stiffening ring 9 to control collapsing of the teat in use. Flow directing means are provided, for example, a one way valve is fitted between the bottle 1 and the teat 5 and preferably this one way valve is in the form of a flap valve 12 (FIG. 2), integral with a cover 13 having an aperture 14 therein, with the flap valve 12 fitting, in use, on the upper face of the cover 13 and over the aperture 14 and being movable by liquid flow or pressure changes to allow the flow of liquid from the bottle 1 to the teat 5 but not vice versa. The cover 13 and flap valve 12 may be made of any suitable material, for example, rubber, but is preferably made of a plastic material, such as polyethylene or polypropylene and the flap valve 12 may be either a separate member fixed to the cover, for example, by heat sealing along a line or may be integral with the cover 13 as shown, with the cover and flap valve being cut out of a sheet of material and then the flap folded over on a fold line 15 coinciding with the edge of the cover 13 so that the flap extends over the aperture 14. To provide pressure equalizing means to equalize pressure as between the inside and outside of the bottle, a collapsible container may be used but I prefer to admit air to the bottle e.g. by the slot or groove 2 or in place of the groove 2 on the bottle 1, a groove 18 may be provided in a washer 19 (FIG. 2).
The preferred way of admitting air into the bottle, however, is to provide a slot or slit 20 in the cover 13 or cover 16 (FIG. 3) which extends to a point 21 (FIGS. 1 and 2) which is inside inner face 22 of the bottle 1 but leaving a portion 23 of the cover still covered by part of an annular disc base 24 of the teat 5 so that air does not enter the teat but enters the bottle 1 beyond washer 19 and which is shown as an alternate arrangement in FIG. 2 to the groove 18. Thus, the slot 20 extends from outside the bottle to within the same.
So that a user will know which way is up to use the cover 13 and flap valve 12 it may be either colored or have printing thereon, the printing for example, reading "this side up" and the color coding being prescribed in the package in which the cover 13 and flap valve are supplied.
The flow directing means above described may, of course, take other forms, it may for example comprise a ball valve and valve seat or may comprise a "tear" type of valve in which a plurality of segments of a valve are arranged on a curved surface, so that pressure from one side will cause them to open away from each other, and pressure from the other side will cause them to close to each other, or the valve may comprise a mitral or aortal type of valve or may comprise a series of flap valves disposed adjacent to each other, or any other convenient type of one way valve may be used. This valve may be replaced by any flow directing means which resists back flow of liquid into the container when the teat is compressed. The preferred alternative device consists of a disc 16 which has a series of perforations 17 provided therein. These may be normal or oblique to the disc 16.
The teat, as stated, preferably has a hard nipple portion adjacent a softer rear portion to give a natural action. The distal hardening may be by a thicker portion of rubber or thickened lines. The proximal dilated portion has annular thickenings to facilitate its restoration after compression.
The operation of the construction is as follows:
When the nipple is applied to a baby's mouth, the natural suckling action of the baby is to bite or chew at the nipple compressing and releasing the nipple. The compression of the nipple causes milk or other liquid contained therein to be squirted from the aperture or apertures in the teat into the baby's mouth. Because of the one way action when the baby's mouth releases the teat, it expands because of the resilience of the material and this draws further milk into the teat, with this milk coming, of course, from the bottle 1. The milk which has thus been removed from the bottle, then creates a slight reduction in pressure in the bottle which draws air into the bottle through groove 2, groove 18 or slot 20 (FIGS. 2 or 3) and this action continues. Of course, the bottle is maintained above the teat in normal use so that the flow of milk is effected by gravity and reverse flow of milk from the teat back into the bottle is prevented or restricted by the flow restricting means.
The construction has many advantages, in particular it is believed that the simulated action is substantially the same as that in natural feeding so that no new technique has to be learned by a baby and consequently weak babies and others who find it difficult to learn artificial feeding can readily be artificially fed. Furthermore, it is believed that the sucking action may have some detrimental physiological action on the baby and consequently from this point alone the construction is justified.
Furthermore, a good flow of milk is provided and there is little likelihood of the baby taking in air with his milk.
|
Artificial baby feeding apparatus for use with a container and teat has a flow directing means in the form of a one way valve or a restriction to prevent or restrict backflow of liquid from the teat to the container. A teat having a soft toroidal distal proximal portion assists in giving a satisfactory pumping action.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application contains disclosure from and claims the benefit under Title 35, United States Code, §119( e ) of the following U.S. Provisional Application: U.S. Provisional Application Ser. No. 60/316,590 filed Aug. 31, 2001, entitled IMPROVED EXCAVATION APPARATUS.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] One aspect of the present invention relates generally to the control of an excavator for breaking-up hard soils, rock, or concrete into manageable sized pieces for subsequent handling or processing. The excavator acts on an existing ground surface, acting on a layer of material to define a new ground surface that is below the original. The process is used for road construction and mining. This aspect of the present invention relates more particularly to the arrangement of sensors and methods of utilizing sensors, which allows control of the depth of cut, orientation of the resulting new ground surface, and location of the new ground surface.
[0005] 2. Description of the Related Art
[0006] Road Bed Preparation
[0007] In the preparation of a road bed one critical function is to establish the proper lateral grade. In most cases the desired lateral grade is level, with the exception of regions where the road curves and a banking effect is desirable. In both cases, when constructing new roads the grade of the native topography will typically need to be modified to achieve the desired grade. Certain ground conditions prohibit excavation in a manner wherein very fine adjustments can be made. These include conditions of rock and very hard soils. In these conditions the surface is typically excavated below the desired level, and finer more manageable materials backfilled to bring the grade to the desired level.
[0008] The process of replacing a damaged road surface often begins with the step of removing the existing road surface. The current methods of removing existing road surfaces of concrete are complicated by the existence of steel reinforcing rod that is integral to the concrete road surface. Current techniques of breaking up the road surfaces are slow and labor intensive often including the use of some form of impact wherein the existing road surface is struck from the above and broken into smaller pieces, and at the same time separating the reinforcing rod.
[0009] Mining
[0010] Many types of non-metallic rock are mined from shallow open-pit mines called quarries. The process is known as quarrying, open cast or surface mining. One quarrying technique involves drilling and blasting to break the rock. When usable rock is found, the surface is cleared to expose the desired rock. The area being mined is then drilled and blasted, a large number of low-powered explosives detonated at the same time to shatter the rock. The drillings are controlled to a depth to stay within the strata of desirable rock, as may have been determined by preliminary exploratory drillings. A single blast produces as much as 20,000 tons of broken stone. The broken stone is then loaded by handling equipment and transported to additional equipment to be crushed into smaller pieces and separated into uniform classes by screening methods. During that time the broken stone is exposed to the elements and some may be affected by weathering damage. This process is relatively labor intensive, produces work-in-process subject to damage. New techniques are recently being developed.
[0011] One such technique of quarrying is labeled as percussive mining in U.S. Pat. No. 5,338,102. In this reference a percussive mining machine is utilized to successively strike or impact the material with a cutting tool. In this case the cutting tools are mounted to a rotating drum that is propelled on a mining machine. The mining machine illustrated includes components representative of many machines which have recently been developed for this application. The machines typically include some form of ground drive, supporting frame for the drum, power unit to provide power to rotate the drum, a conveyance mechanism and some form of height control, to control the position of the drum. Examples of other machines, built specifically for this application, can be found in U.S. Pat. Nos. 5,092,659; 5,577,808; and 5,730,501. These machines are highly specialized, with limited additional use.
[0012] An example of a more versatile machine, built on a more generic platform, can be found in U.S. Pat. No. 4,755,001. This reference discloses an excavating machine that consists of a digging head mounted to an elongated digging member, both mounted to a main frame. The main frame resembles machines currently known as track trenchers.
[0013] Track trenchers, as is illustrated in FIG. 1, were originally designed for forming trenches for the installation of drainage lines or other utilities in open trench installations. The basic components of a Track Trencher 10 include:
[0014] 1) a main frame 30 ;
[0015] 2) a set of ground engaging track assemblies 20 which are fixedly supported by the main frame 30 in a manner that allows the drive sprocket 22 to be driven to propel the machine along the ground;
[0016] 3) a power unit 40 typically a diesel engine; and
[0017] 4) an excavation boom assembly 50 which is relatively narrow, as compared to its length, as most trenches are much deeper than they are wide.
[0018] The power unit 40 provides power to the driven/drive components of the machine. This is typically comprised of a diesel engine and a hydraulic system. The hydraulic power is transferred to various actuators mounted on the machine to perform the desired operations including:
[0019] 1) a hydraulic motor 24 mounted onto the track drive frame that drives the track drive sprockets 22 ;
[0020] 2) a hydraulic motor 52 mounted on frame 30 that supports and drives a sprocket which drives the excavation chain 54 that is supported on an idler sprocket 56 which is supported by the boom frame 51 ; and
[0021] 3) a hydraulic system that includes lift cylinders 62 to raise and lower the excavation assembly
[0022] In trenching the primary parameter that needs to be controlled is the depth of the trench. The machine provides this control by controlling the position of the boom relative to the ground engaging tracks, typically allowing the boom to pivot around an axis defined by the machine frame. This pivot is designed robustly to handle the severe loading, particularly experienced when excavating rock. Typically the only movement of the boom relative to the frame is provided by pivoting about this axis.
[0023] Controlling the height of each ground drive unit, track, independently allows the frame to be kept level and thus the orientation of the resulting trench can also be controlled. However, this technique of orientation is not ideal in that the entire machine is being controlled resulting in higher power requirements and reduced responsiveness.
BRIEF SUMMARY OF THE INVENTION
[0024] The present invention relates generally to an excavation machine having a frame and an excavation boom. The excavation boom is pivotally mounted to the frame at a boom mount pivot axis to allow control of the excavation depth. The excavation boom includes an excavating chain that drives an excavating drum, both rotating about an excavation axis. The boom further includes an integral pivot that allows the position and/or orientation of the excavating drum to be adjusted, relative to the frame and the boom mount pivot axis.
[0025] Road Bed Preparation
[0026] The present invention is particularly useful for providing a control system wherein the initial excavation for a road bed can be accomplished in a manner that is accurate and precise allowing the depth of excavation and the related amount of backfill material necessary to be reduced to a minimum.
[0027] Mining
[0028] The apparatus of the present invention is particularly useful for certain types of mining operations with its ability to control the excavating drum to optimize the orientation of the ground surface and the excavating parameters.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] [0029]FIG. 1 is a side view of the prior art track trencher with a standard boom;
[0030] [0030]FIG. 2 is a side view of a track trencher with an alternative boom;
[0031] [0031]FIG. 2 a is an enlarged partial side view of a track like that shown in FIG. 2;
[0032] [0032]FIG. 3 is a top view of a track trencher with an alternative boom;
[0033] [0033]FIG. 4A is a preferred embodiment of the hydraulic schematic illustrating an auto down pressure configuration for the boom;
[0034] [0034]FIG. 4B is the preferred embodiment of the hydraulic schematic illustrating an auto down pressure configuration for the stabilizers;
[0035] [0035]FIG. 5 is the preferred embodiment of a hydraulic schematic illustrating the position control configuration;
[0036] [0036]FIG. 6 is the preferred embodiment of a electrical schematic illustrating the pitch control circuit for the boom;
[0037] [0037]FIG. 7 is a schematic illustration of an operator control panel allowing appropriate selection of auto down pressure, position and pitch control;
[0038] [0038]FIG. 8 is a schematic of an alternate embodiment of a control system;
[0039] [0039]FIGS. 9A, 9B and 9 C are sequential side views that illustrate a trencher traveling along an existing ground surface that includes a bump; and
[0040] [0040]FIGS. 10A, 10B and 10 C are sequential side views that illustrate a trencher traveling along an existing ground surface that includes a bump like FIGS. 9A, 9B and 9 C but with the boom set to pitch control using the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0041] Referring now to the drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, FIGS. 2 and 3 illustrate a track trencher with an alternative excavation boom 100 , as disclosed in co-pending U.S. Patent Application Serial No. ______. The track trencher comprises track assemblies 20 , frame 30 , power unit 40 , and excavating boom 100 including head unit 130 , which supports excavation assembly 140 . The orientation of the base machine is defined by the existing ground surface 180 . The areas contacted by the two track assemblies 20 will define the effective ground plane 180 , oriented at an angle relative to gravity, the effective grade.
[0042] The location and orientation of the excavation assembly 140 will define the new ground surface 182 . This location and orientation is controlled by several elements. The position of the boom 100 relative to frame 30 is controlled with lift cylinders 62 , which effectively rotate boom 100 about axis 114 , defined by frame 30 as parallel to the existing ground surface 180 , to effectively control the excavation depth, relative to the track assemblies 20 .
[0043] The orientation of the excavation assembly 140 , relative to the frame 30 , is controlled with tilt cylinders 64 , which rotate the head unit 130 about swivel axis 124 . Swivel axis 124 , in this preferred embodiment, is perpendicular to axis 114 , allowing the orientation of the head unit 130 and excavation assembly 140 to be modified relative to axis 114 and the ground plane 180 . Alternatively, a swivel axis, not shown, could be merely parallel with swivel axis 124 .
[0044] The excavation assembly 140 is designed to be in contact with the ground in order to excavate a certain depth, the difference between the existing ground surface 180 and the new ground surface 182 . The amount of force necessary to hold the excavation assembly 140 in the position to maintain a consistent excavation depth, excavation force, depends greatly on the type of material being excavated. In some conditions the weight of the head unit 130 is sufficient, and the excavation force is equal to the weight of the head unit 130 . At other times additional force is required, and the lift cylinders 62 are utilized to effectively transfer some of the weight of the base machine to the excavation assembly 140 .
[0045] As shown in FIG. 2, the positioning assembly 170 also affects the loading and position of the excavation assembly 140 relative to the existing ground plane 180 . Stabilizer cylinders 66 extend from the frame of head unit 130 to bogey wheels 172 which may or may not be in contact with existing ground surface 180 . If in contact they carry at least a portion of the excavation load.
[0046] The positioning assembly 170 (FIGS. 2 and 2 a ) is comprised of a stabilizer frame 176 which connects to the stabilizer cylinder 66 at a pivot point 174 . The stabilizer frame 176 provides mounts for the bogey wheels 172 . The bogey wheel and frame 176 are free to rotate around the pivot point 174 . By freely rotating the pivot point 174 does not need to move as much when encountering relatively small surface irregularities. As illustrated in FIG. 2 a , with certain irregularities, such as bump 185 , the travel of pivot 174 will be approximately ½ the actual height of the bump as can be seen by comparing dimension A to dimension B.
[0047] The control of the position and orientation of the excavation assembly thus includes appropriate control of the lift cylinders 62 , the tilt cylinders 64 and the stabilizer cylinders 66 . The present invention involves techniques to control the excavation depth, or alternately to control the contour of the new ground surface 182 by coordinated control of these cylinders.
[0048] One technique for controlling the position of the excavation assembly 140 is to control the excavation force. The excavation force is comprised of a portion of the weight of the excavation boom 100 , that not carried by the base machine, plus the portion of the weight of the base machine transferred to the boom 100 minus the weight borne by the position stabilizer assembly 170 . Controlling the pressure applied to the lift cylinders 62 controls the portion of the weight of the base machine transferred to the boom 100 , a technique known as Auto-Down pressure. The preferred embodiment of the hydraulic circuit 450 that enables this control technique, in the configuration of Auto-Down for the boom 100 , is illustrated in FIG. 4A.
[0049] The basic circuit includes a pump assembly 450 , comprising pump 402 and control valves, that are capable of providing pressurized hydraulic fluid to a supply line 452 which transfers the fluid to valve 420 . Valve 420 is a directional control valve, known as a 3-position valve, illustrated directing the hydraulic fluid to port labeled B, and to line 454 which transfers the pressurized fluid to pressure reducing/relieving valve 410 . Valve 420 is controlled to be in this position by energizing solenoid 420 B.
[0050] The pressure reducing/relieving valve 410 is controlled by valve 456 , a poppet valve. If the solenoid of poppet valve 456 is energized, as illustrated in FIG. 4A, it will open a flow path from the pilot end of valve 410 to relief valve 460 through fluid supply line 458 . The relief valve will control the fluid pressure in fluid supply line 458 , which in turn controls the pressure at which valve 410 effectively operates. Valve 410 effective operates to reduce or relieve the fluid pressure in fluid supply line 462 , to a controlled pressure, as set by the adjustment of relief valve 460 . The fluid, under controlled pressure, in fluid supply line 462 is transferred to poppet valve 464 and counter balance valve 466 . Counter balance valve 466 functions during position control operation, but in the Auto-Down operation is not necessary. Thus, poppet valve 464 effectively bypasses the counterbalance valve 466 by energizing its solenoid at the same time that the solenoid of valve 456 is energized. The two solenoids are simply wired in parallel.
[0051] As illustrated by this hydraulic schematic of FIG. 4A, the hydraulic fluid is transferred from pump 402 to the cylinders 62 in a manner that the cylinders will exert a constant force, attempting to rotate the boom 100 counterclockwise with the machine as illustrated in FIG. 2. Hydraulic fluid will flow from the pump 402 to the cylinders 62 at the reduced pressure set by valve 410 , as valve 410 functions as a pressure reducing valve, when the boom 100 rotates counterclockwise. Hydraulic fluid will flow from the cylinders 62 to the tank, as valve 410 functions as a pressure relieving valve, through fluid supply line 468 , when the boom 100 is required to rotate clockwise, as when traveling over a surface irregularity. The desired result is that a nearly fixed amount of force, resulting from the transfer of weight from the base machine to the boom 100 , is applied to the excavation assembly 140 , as the boom 100 is allowed to float to follow the ground surface.
[0052] [0052]FIG. 4B illustrates a preferred embodiment of a hydraulic circuit in a configuration that enables a constant down force on the stabilizer assembly 170 . This circuit operates in a fashion similar to that described for the boom cylinders 62 as illustrated in FIG. 4A. In the configuration of FIG. 4B, constant down force is applied to the stabilizer assembly 170 by stabilizer cylinders 66 . Hydraulic fluid is transferred from the pump 402 to valve 422 through fluid supply line 452 . From valve 422 the fluid is transferred through counterbalance valve 470 , and pilot operated check valve 472 , both with functions unrelated to the auto down pressure. The fluid is then transferred to pressure reducing/relieving valve 474 . The pressure reducing/relieving valve 474 is controlled by valve 476 and relief valve 460 .
[0053] As illustrated in FIG. 4B, the solenoid of valve 476 is energized, allowing the pressure in pilot line 458 to effectively control valve 474 . Valve 474 functions to reduce the pressure from the pump 402 to a set value and by relieving the pressure, potentially generated by the cylinders 66 , to that same pressure. This allows the stabilizer cylinders 66 to move, to follow the topography, while maintaining a consistent force. This force is adjustable by adjusting the pressure in fluid transfer line 458 , by adjusting relief valve 460 . The pressure is adjustable from the operator's station 300 with adjustment 302 , as illustrated in FIG. 7, which effectively adjusts relief valve 460 which is physically located at the control panel. An operator, using pressure gauge 303 , can monitor the pressure in fluid transfer line 458 .
[0054] The operator's station 300 also includes a selector switch 304 , with 3 positions 304 A, 304 B and 304 C. In position 304 A Auto-Down is selected to control pressure to the boom, which increases the excavation force by transferring additional weight to the boom with lift cylinders 62 .
[0055] Still referring to FIG. 7, in position 304 C Auto-Down is selected for the Stabilizer, to apply a controlled pressure to the stabilizer cylinders 66 . The net effect on the excavation force is opposite that described for the auto down pressure for the boom. The controlled pressure is controlling the weight borne by the stabilizer cylinders 66 , which reduces the excavation force.
[0056] Still referring to FIG. 7, in position 304 B Auto-Down is turned off, resulting in de-energizing of the solenoids for valves 464 , 456 and 476 to effectively disable the pressure reducing/relieving valves 410 and 474 . Disabling these valves 464 , 456 and 476 will allow the hydraulic circuit to function in a position control mode, as illustrated in FIG. 5.
[0057] In some applications control of position/orientation is useful. The operator station 300 of FIG. 7 illustrates two position control options: pitch control and position control. The preferred hydraulic circuit is illustrated in the configuration for position control in FIG. 5 where valve 420 controls position of the boom 100 , valve 422 controls position of the stabilizer cylinders 66 , and valve 424 controls the tilt cylinders 64 . These valves 422 can be controlled manually by switches 320 , 322 and 324 as illustrated in FIG. 7, if the valves 422 are actuated by solenoids. Each of the switches 320 , 322 and 324 has a first position in which the appropriate cylinder 66 will be extended, a second position in which the appropriate cylinder 66 will be retraced and a third, middle, position in which the cylinders 66 are held in position. They could alternately be controlled mechanically through cables or direct linkage. Many techniques of controlling position control valves are well known, any such technique could be utilized.
[0058] Pitch control is another form of position control, and can be selected from operator station 300 (FIG. 7). Switch 326 allows selection of pitch control of the boom 100 , and switch 328 allows selection of pitch control of the tilt cylinders 64 . The pitch control is enabled by the preferred embodiment of electrical circuit illustrated in FIG. 6 for the boom 100 , comprising a four-way, three-position solenoid valve 420 , corresponding to valve 420 illustrated in FIGS. 4A, 4B and 5 , and a tilt sensor 351 . Tilt sensor 351 includes a center member 356 that freely rotates in housing 358 such that its position is determined by gravity. The tilt sensor 351 is secured to the excavation boom 100 , as illustrated in FIG. 2, contains two sensor pads 352 and 354 . When the housing is tilted clockwise, indicating the boom 100 has rotated clockwise, the center member 356 will contact pad 354 . This will result in energizing solenoid 420 B which will shift valve 420 into a position to direct oil to rotate the excavation boom 100 counterclockwise. Many types of tilt sensors are commercially available including those wherein there is no physical contact, wherein there are magnetic reed switches and the center member includes a magnet that causes the reed switches to close when in close proximity. The type of switch is not important.
[0059] Solenoid 420 B will remain energized until the boom 100 has rotated counterclockwise far enough such that the center member 356 of tilt sensor 350 is no longer contacting pad 354 . The system operates in a similar manner if the boom 100 is positioned too far counter clockwise wherein pad 352 is contacted, solenoid 420 A is energized resulting in the boom moving clockwise.
[0060] A similar electrical circuit will enable pitch control for the tilt cylinders 64 with a tilt sensor 350 installed to detect the orientation of the head unit 130 (as illustrated in FIG. 2) and is enabled by switch 328 .
Operation
[0061] In operation, the auto-down control is given precedence. For instance, referring to FIG. 7, the operator can select auto-down pressure for the boom 100 , by positioning switch 304 in position 304 C, and at the same time select pitch control for the boom 100 , by positioning switch 326 in position 326 A. In this scenario, the auto-down pressure overrides, and the tilt sensor is ignored.
[0062] This precedent relationship can be defined by appropriate wiring techniques, or could alternately be defined using a programmable logic controller of any known type.
[0063] The purpose of the auto-down control has previously been described in the description of the hydraulic circuits: to provide a consistent force to either the boom, to increase the excavation force, or to the stabilizer cylinders 66 to effectively reduce the excavation force. A preferred operating configuration is to have the auto-down control activated for the boom while the stabilizer cylinders 66 are set at a given position. This provides consistent load on the excavating assembly 140 while providing depth control with the position of the stabilizer cylinders 66 .
[0064] Referring again to FIG. 7, the pitch control (switch 328 ) for the tilt provides a mechanism to hold the tilt of excavation assembly 140 constant to provide a new ground surface 182 of a consistent pitch or grade. The purpose of the pitch control of the boom 100 , using switch 328 , is to provide a new ground surface 182 that is smoother than the existing ground surface 180 .
[0065] This is illustrated in FIGS. 9A, 9B, 9 C, 10 A, 10 B and 10 C. FIGS. 9A, 9B and 9 C illustrate trencher 10 traveling along an existing ground surface 180 that includes a bump 184 . In these figures, the excavation boom 100 is position controlled and its orientation relative to the base machine is fixed, while the stabilizer cylinders 66 are controlled for auto-down pressure.
[0066] As illustrated in FIG. 9B, the tracks will initially climb the bump 184 , causing the excavation assembly 140 to be lowered. The machine will continue to travel along the ground and, as illustrated in FIG. 9C, the bump 184 will eventually be under the opposite end of the tracks. In this position the excavation assembly would be raised, to the point it will not even contact the ground. The net effect is that the new ground plane 184 will contain a bump 186 that is larger than the original bump 184 as illustrated in FIG. 9C.
[0067] [0067]FIGS. 10A, 10B and 10 C illustrate the same base trencher of FIGS. 9A, 9B and 9 C traveling over the same bump 184 , but this time with the boom 100 set, using switch 238 , to pitch control. Using the pitch control, the boom 100 is controlled such that its engagement with the ground is improved, and the bump 186 in the new ground surface 184 is less defined than the original bump 184 . In this manner the surface is improved. FIG. 10A looks essentially like FIG. 9A. However, in FIG. 10B it can be seen that the pitch control has pivoted the boom 100 upwardly compared to the boom 100 shown in FIG. 9B so that the bump 186 is reduced in FIG. 10B compared to bump 186 in FIG. 9B. In FIG. 10C, the boom 100 is now lowered with respect to the surface 180 compared to the boom 100 in FIG. 9C so that it can better remove bump 184 .
[0068] [0068]FIG. 8 illustrates several alternative embodiments of a control system of the present invention that would provide increased capability. A hydraulic control system 60 includes lift cylinder(s) 62 , tilt cylinder(s) 64 and stabilizer cylinder(s) 66 in addition to control valves 67 .
[0069] A controller 200 is capable of accepting inputs and controlling outputs to control various mechanical elements of the trencher. The control system would be capable of controlling many systems other than illustrated in this Fig, including the drive motor to the tracks 24 and excavation boom hydraulic motor 52 as disclosed in U.S. Pat. Nos. 5,590,041; 5,574,642; 5,509,220 which are all incorporated herein by reference. For the purpose of explaining the current invention, the control aspects related to positioning the excavating boom are included in FIG. 8. The primary outputs required for this control are the outputs for controlling valves 67 and display 230 . Inputs could include:
[0070] 1) an indication of the relative position of the head unit 130 as tilted on axis 124 , which can be indicated with a rotary potentiometer 202 ;
[0071] 2) an indication of the relative position of the mount section 110 as tilted on axis 114 , an indication of cutting depth, which can be indicated with a rotary potentiometer 204 ;
[0072] 3) an indication of the position of the stabilizers as indicated with a rotary potentiometer 203 ;
[0073] 4) An indication of the relative height of the right side of the excavating drum 148 R, which can be indicated with a laser target 206 ;
[0074] 5) An indication of the relative height of the left side of the excavating drum 148 L, which can be indicated with a laser target 208 ;
[0075] 6) An indication of the pitch of the new ground surface 172 , which can be indicated by a tilt sensor 210 mounted on the head unit 130 of the excavating boom assembly 100 ;
[0076] 7) An indication of the depth of cut which can be indicated by a tilt sensor 211 mounted in fixed relationship to axis 124 ;
[0077] 8) An indication of the position of the excavating boom assembly 100 which can be indicated by a Global Position Sensor 212 mounted onto the head unit 130 ;
[0078] 9) An indication of the sub-surface conditions can be determined by a GPR unit 214 or other sensors. Techniques of performing these types of subsurface surveys are disclosed in U.S. Pat. Nos. 6,195,922; 6,119,376; 5,704,142; 5,659,985; 5,553,407 and pending application Ser. No. 60/211,431 all of which are hereby incorporated by reference. Mounting the sensors onto the track trencher in an appropriate location will provide the capability to do real-time monitoring and control of the excavating process.
[0079] 10) An alternate and preferable technique is be to mount a GPS sensor 216 , subsurface sensors like a GPR 218 or any other such sensor, possibly a relative height sensor as in a laser target 220 onto a separate cart and perform preliminary surveys. The information generated by the preliminary surveys could be contained in a database 222 , post processed by a planning/analysis system 224 wherein the 3-D contour of the desirable geology is identified. The contours can be evaluated and an optimized excavation route determined optimizing production rates, minimizing travel/turn requirements, minimizing any non-productive activity required, etc. The resulting excavation plan can then be insert into the controller 200 where it may be used to provide a control signal to an operator via display 230 , or alternatively to control the excavator directly.
[0080] With this or similar arrangements of components the excavation process can be controlled in a variety of manners to achieve various results.
[0081] If a subsurface survey is completed and a map/plan developed, the inputs which allow determination of the depth of the excavation, the rotary pots 204 and 202 and height sensors 206 and 208 , can be used to control the excavator to excavate to a certain depth while also maintaining control to a set depth of cut. The inputs can be used to control both in a manner to optimize the excavation process.
[0082] Likewise if the subsurface survey is completed in real-time, the ultimate depth of the excavation, the location of the new ground surface 182 , can be determined in a manner to optimize both the location of that surface and the depth of cut.
[0083] The result of the various embodiments is an excavation machine that provides a variety of control modes allowing the operator to select the mode best suited for the conditions. The embodiments range from basic switches with no controller, to the most complex system comprising a controller and the ability to incorporate logic.
[0084] A primary consideration in this excavation process is the quality of the excavated material. The previously described control systems provide a means of varying operation and control associated with depth of cut to affect the quality of this final product. Additionally the depth of cut can be utilized in conjunction with controlling the ground speed of the excavator to optimize the quality of the resulting product. It has been found that operating the machine in a mode of relatively high ground speed, with relatively shallow excavation depth yields the best quality of product and the highest productivity, for certain materials. With the control systems of the present invention the operation of the excavation machine can be controlled to achieve the desired result.
[0085] Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
|
A method and apparatus for controlling an excavator having a frame, engine, ground supports and an excavation boom with an excavating drum. The method includes fixing the orientation of the boom relative to gravity to approximately control the shape of an excavated ground plane.
| 4
|
[0001] This application is a continuation of International Application No. PCT/JP02/05891, filed Jun. 13, 2002, which claims the benefit of Japanese Patent Application Nos. 181416/2001, filed Jun. 15, 2001, 143441/2002, filed May 17, 2002, 143442/2002, filed May 17, 2002 and 143443/2002, filed May 17, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a light emitting device utilizing an organic compound, and more detailedly to a light emitting device, particularly an organic electroluminescent device (organic EL device), having excellent luminance, efficiency and drive durability by doping a light emitting layer with plural compounds.
[0004] 2. Related Background Art
[0005] The organic EL device is being actively investigated for its applications as a light emitting device capable of showing a high speed response and a high efficiency. The basic configuration of such device is shown in FIGS. 1A , 1 B and 1 C (for example see. Macromol. Symp., 125, 1-48 (1997)).
[0006] As shown in FIGS. 1A , 1 B and 1 C, the organic EL device is generally composed, on a transparent substrate 15 , of a transparent electrode 14 , a metal electrode 11 , and an organic layer sandwiched therebetween and consisting of plural organic films.
[0007] In the configuration shown in FIG. 1A , the organic layer consists of a light emitting layer 12 and a hole transport layer 13 . The transparent electrode 14 is composed for example of ITO having a large work function, thereby achieving satisfactory hall injection characteristics from the transparent electrode 14 into the hole transport layer 13 . The metal electrode 11 is composed of a metallic material of a small work function such as aluminum, magnesium or an alloy thereof for achieving satisfactory electron injection characteristics into the light emitting layer 12 . These electrodes have a film thickness of 50 to 200 nm.
[0008] In the light emitting layer 12 , there is employed for example an aluminum quinolinol complex having electron transporting property and light emitting characteristics (as exemplified by Alq3 shown in the following). Also in the hole transport layer 13 , there is employed a material showing electron donating property such as a biphenyl diamine derivative (as exemplified by α-NPD shown in the following).
[0009] The device of the above-described configuration shows an electric rectifying property, and, when an electric field is applied in such a manner that the metal electrode 11 becomes a cathode and the transparent electrode 14 becomes an anode, the electrons are injected from the metal electrode 11 into the light emitting layer 12 and the holes are injected from the transparent electrode 14 into the light emitting layer 12 through the hole transport layer 13 .
[0010] The injected holes and electrons cause recombination in the light emitting layer 12 to generate excitons, thereby generating light emission. In this operation, the hole transport layer 13 serves as an electron blocking layer, whereby the efficiency of recombination is increased at the interface of the light emitting layer 12 and the hole transport layer 13 thereby improving the light emitting efficiency.
[0011] In the configuration shown in FIG. 1B , an electron transport layer 16 is provided between the metal electrode 11 and the light emitting layer 12 in FIG. 1A . Such configuration separates the light emission from the transportation of electrons and holes, thereby achieving more efficient carrier blocking and realizing efficient light emission. As the electron transport layer 16 , there can be employed, for example, an oxadiazole derivative.
[0012] Conventionally, the light emission in the organic EL device is generally based on the fluorescence of molecules of a high emission center in a shift from a singlet exciton state to a base state. On the other hand, there is being investigated a device utilizing phosphorescence through a triplet exciton state, instead of the fluorescence through the singlet exciton state. Representative examples of the references reporting such device are:
1) D. F. O'Brien et al, Improved Energy Transfer In Electrophosphorescent Device, Applied Physics Letters Vol. 74, No. 3, p. 422 (1999), and 2) M. A. Baldo et al, Very High-efficiency Green Organic Light-emitting Devices Based On Electrophosphorescence, Applied Physics Letters, Vol. 75, No. 1, p. 4 (1999).
[0015] In these references, there is principally employed an organic layer of a 4-layered configuration as shown in FIG. 1C , consisting of a hole transport layer 13 , a light emitting layer 12 , an exciton diffusion preventing layer 17 and an electron transport layer 16 from the anode side. There are employed following carrier transporting materials and phosphorescence emitting materials, which are abbreviated as follows:
[0016] Alq3: aluminum-quinolinol complex
[0017] α-NPD: N4,N4′-dinaphthalen-1-yl-N4,N4′-dipheny-biphenyl-4,4′-diamine
[0018] CBP: 4,4′-N,N′-dicarbazole-biphenyl
[0019] BCP: 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline
[0020] PtOEP: platinum-octaethylporphilline complex
[0021] Ir(ppy) 3 : iridium-phenylpyridine complex
[0000]
[0022] Also Forrest et al., Nature, 403, p. 750 discloses an EL device of laminated structure utilizing CBP as a host material of the light emitting layer, and causing triplet-singlet energy transfer from a green light emitting layer based on Ir(ppy)) 3 to a red light emitting layer based on DCM (dicyanomethylene).
[0023] These configurations are different from that of the present invention in that the co-existing light emitting materials have distant light emitting wavelengths and that the forming method does not involve vacuum evaporation of a mixture, as will be clarified later in the examples.
[0024] In the above-described organic EL device utilizing phosphorescent light emission, it is important to inject a larger amount of carriers into the light emitting layer at a lower voltage while maintaining the balance of electrons and positive holes at such lower voltage, in order to achieve a high luminance and a high efficiency.
[0025] Among such phosphorescent materials, there are known ones with low charge injecting and charge transporting properties, in which it is difficult to cause a large current at a low voltage.
[0026] Also many organic materials are known to form a cluster of plural molecules at the evaporation, and the light emitting layer involving such clusters is considered to show a locally high concentration of the light emitting material, leading to a loss in the light emitting efficiency of the device.
[0027] Also the organic materials are known to cause deterioration of the characteristics, for example by crystallization of the same molecules in the light emitting layer.
[0028] Because of the above-described background, there is desired a light emitting device capable of providing a high luminance of light emission and a long service life.
SUMMARY OF THE INVENTION
[0029] In consideration of the drawbacks in the conventional technologies explained in the foregoing, the object of the present invention is to provide an organic EL device utilizing an organic light emitting material, enabling low-voltage drive and achieving a high luminance, a high efficiency and a high durability.
[0030] The above-mentioned object can be attained, according to the present invention, by a light emitting device provided with electrodes consisting of an anode and a cathode formed on a substrate and an organic light emitting layer between such electrodes, the device being featured in that the aforementioned light emitting layer contains a light emitting material and a dopant for improving the dispersibility thereof.
[0031] The light emitting device of the present invention is also featured in that the aforementioned dopant is composed of a light emitting compound, and that the light emission spectrum of the aforementioned light emitting material and that of the light emitting compound mutually overlap in a principal portion.
[0032] The relationship between the light emission wavelength and the quantum yield of the aforementioned light emitting material and the aforementioned light emitting compound is preferably such that the quantum yield of either having a shorter light emission wavelength is larger than that of the other having a longer light emission wavelength.
[0033] At least either of the aforementioned light emitting material and the aforementioned light emitting compound is preferably a metal complex and/or an organic compound, and they preferably have respectively different HOMO levels.
[0034] The difference in the peak wavelengths of the light emission spectra of such light emitting material and light emitting compound preferably does not exceed 30 nm.
[0035] The aforementioned light emitting material and light emitting compound are preferably composed of plural metal complexes having a same ligand skeletal structure with respectively different substituents in such ligand skeleton, and the central metal of the metal complexes is preferably iridium.
[0036] The present invention is also featured by a producing method in which the light emitting material and the light emitting compound are mixed and are subjected to vacuum evaporation in a single heating container.
[0037] The light emitting device of the present invention is also featured in that the aforementioned dopant is composed of a non-light emitting compound.
[0038] Such non-light emitting compound preferably has a boiling point lower than that of the aforementioned light emitting material.
[0039] Also such non-light emitting compound preferably has a band gap larger than that of the light emitting material.
[0040] The proportion of the light emitting material and the non-light emitting compound in the organic light emitting layer is preferably changed depending on the position therein. The light emitting material is preferably a phosphorescent light emitting material in terms of the light emitting efficiency.
[0041] The light emitting device of the present invention is further featured in that the organic light emitting layer contains a light emitting material and a current enhancing material.
[0042] Preferably such current enhancing material is composed of a light emitting material and has a quantum yield lower than that of the aforementioned light emitting material, and the difference of the peak wavelengths in the light emission spectra of these materials preferably does not exceed 30 nm.
[0043] The aforementioned current enhancing material has a band gap larger than that of the aforementioned light emitting material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] FIGS. 1A , 1 B and 1 C are schematic views showing examples of the configuration of the light emitting device of the present invention, wherein FIG. 1A shows a device configuration with a two-layered organic layer, FIG. 1B shows a device configuration with a three-layered organic layer, and FIG. 10 shows a device configuration with a four-layered organic layer;
[0045] FIG. 2 is a chart showing light emission spectra of the light emitting material and the light emitting compound employed in the present invention, with the abscissa representing wavelength and the ordinate representing normalized intensity of light emission, illustrating an example of an Ir complex C and an Ir complex D and showing a fact that the light emission spectra mutually overlap in a principal portion; and
[0046] FIG. 3 is a chart showing light emission spectra of a reference example, indicating that the light emission spectra mutually overlap less and have mutually distant peak wavelengths.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] The light emitting device of the present invention is provided with an anode, a cathode, and an organic light emitting layer sandwiched between the anode and the cathode. The organic light emitting layer is not particularly limited in configuration, and may assume configurations as shown in FIGS. 1A , 1 B and 1 C.
[0048] The light emitting device of the present invention is featured in that the organic light emitting layer contains a light emitting material and a dopant for improving the dispersibility of the light emitting material, particularly a light emitting compound, or a non-light emitting compound, or a current enhancing material. The aforementioned dopant provides various improvements such as:
[0049] (1) increasing the device current even in a device with a light emitting layer in which the carrier injection or carrier movement is difficult, for example a light emitting layer utilizing a phosphorescent light emitting material, thereby achieving a decrease in the drive voltage or a higher light emitting efficiency;
[0050] (2) suppressing the crystallization in the light emitting layer, thereby extending the service life of the device;
[0051] (3) reducing the evaporation temperature by co-evaporation with the light emitting material; and
[0052] (4) changing the light emitting position within the light emitting layer, thereby achieving an increase in the luminance etc.
[0053] The light emitting device of the present invention is featured, in comparison with a light emitting device having a similar configuration except for the organic light emitting layer, by a larger current or a higher light emission luminance under the application of a similar voltage, or a longer durability in continuous drive, because of a fact that the organic light emitting layer is not constituted by a single light emitting material but is a mixed light emitting layer consisting of a light emitting material and a light emitting compound.
[0054] The dopant, in case of a light emitting compound, preferably has a light emission quantum yield lower than that of the principal light emitting material. In this manner the principal light emitting material represents a major portion of the light emission luminance while the contribution of the dopant or the light emitting compound to the light emission luminance can be made smaller.
[0055] A second function of the dopant is to stabilize the light emitting material present in the light emitting layer. In such function, the light emitting compound preferably has a molecular structure different from that, of the light emitting material and capable of inhibiting the crystallization or dimerization in the base state or the formation of an associate in the excited state. The light emitting material and the light emitting compound are desirably similar in the light emitting property but are different in the molecular structure, for example, in case of metal complexes, having a same basic skeletal structure but being different in the substituents.
[0056] A third function of the dopant is to control the molecular flow at the evaporation. The evaporation under heating of a mixture of plural materials of different evaporation temperatures allows to suppress the formation of a cluster such as microcrystals. Such effect can be expected for example by evaporating a fluorinated organic compound together with the light emitting material.
[0057] For example following compounds can be conceived as a fluorinated ligand of iridium complex:
[0000]
[0058] In case a light emitting compound is employed as the dopant, it is important to obtain light emission as close as possible to a single color. It is therefore preferred that the light emission spectrum of such light emitting compound overlaps with that of the light emitting material in a principal portion, or that the difference of the peak wavelengths in the light emission spectra of the two does not exceed 30 nm.
[0059] For example, in case the light emitting material emits red light and the intensity ratio of the light emission of the light emitting material and the light emitting compound is 10:1, it is confirmed by a simulation that the CIE coordinate value of the emitted light does not change significantly if the difference of the peak wavelengths in the light emission spectra is 30 nm or less. Therefore, from the standpoint of obtaining light emission of a high color saturation, it is preferred that the difference of the peak wavelengths in the light emission spectra of the light emitting material and the light emitting compound does not exceed 30 nm.
[0060] In this manner there can be obtained a device showing little change in the color saturation even when light is emitted from both the light emitting material and the light emitting compound. Also, in case an energy transfer is involved from the light emitting compound to the light emitting material, there can be obtained an advantage of facilitating such energy transfer because of the small energy difference.
[0061] Also by selecting the band gap of the light emitting compound larger than that of the light emitting material, the recombination of electron and positive hole tends to take place easier on the light emitting material than on the light emitting compound, whereby the light emission can be obtained principally from the light emitting material.
[0062] In the present invention, the proportion of the light emitting material and the light emitting compound may be varied depending on the location within the organic light emitting layer, thereby controlling the distribution of the electrons and the positive holes within the light emitting layer, and regulating the position of the electron-positive hole recombination within the light emitting layer. In this manner there can be prepared a device of high efficiency with satisfactory light emission color.
[0063] In the present invention, the non-light emitting compound means a compound which is significantly inferior to the aforementioned light emitting compound in the light emitting property and does not emit electroluminescent light singly, thus not contributing to the light emission of the EL device.
[0064] The light emitting layer is generally composed of the light emitting material dispersed in a host material having electroconductivity, but can also be composed of the light emitting material only. The present invention is featured in that a dopant is further added to such materials. The host material can be, for example, CBP or TAZ, and the light emitting compound employable in the present invention can be, for example, the compound A shown below, CBP or Ir complex A.
[0065] The light emitting material can be, for example, Ir complex B, Ir(ppy) 3 , or Ir complex C.
[0066] In the following there are shown the structures of other compounds, in addition to those mentioned in the foregoing:
[0000]
EXAMPLES
[0067] At first there will be explained a common part of the device preparation processes employed in the examples 1 and 2.
[0068] In these examples, there was employed a device configuration with a four-layered organic layer as shown in FIG. 1C . An ITO film (transparent electrode 14 ) of a thickness of 100 nm was patterned on a glass substrate (transparent substrate 15 ). On thus prepared ITO substrate, following organic layers and electrode layers were formed in succession by vacuum evaporation by resistance heating in a vacuum chamber of 10 −4 Pa:
[0069] hole transport layer 13 (40 nm): α-NPD
[0070] light emitting layer 12 (40 nm): host material+light emitting material+light emitting compound
[0071] exciton diffusion preventing layer 17 (10 nm): BCP
[0072] electron transport layer 16 (30 nm): Alq3
[0073] metal electrode layer 1 (15 nm): AlLi alloy (Li content 1.8 wt. %)
[0074] metal electrode layer 2 (100 nm): Al
[0075] These layers were so patterned that the electrodes have an opposed area of 3 mm 2 .
Example 1
[0076] A device was prepared by employing CBP as the host material of a light emitting layer and doping the light emitting layer with the Ir complex C as the light emitting material at a concentration of 7 wt. % and with the Ir complex A as the light emitting compound at a concentration of 3 wt. %. The employed Ir complex A has a function of increasing the current in the device, thus also serving as the current enhancing material.
Comparative Example 11
[0077] A device was prepared as in the example 1, except that the doping with the Ir complex A as the light emitting compound was not executed.
[0078] Table 1 shows the results of measurement of current and luminance of these devices under the application of a DC voltage of 10 V.
[0000]
TABLE 1
Current (mA/cm 2 )
Luminance (cd/m 2 )
Example 1
80.2
806
Comp. Ex. 11
11.8
426
[0079] The example 1, utilizing the Ir complex A as the light emitting compound, showed increases in the current and in the luminance. Also the current enhancing effect of the Ir complex A could be confirmed from a significant increase in the device current.
[0080] The light emission spectrum shows not only the light emission from the Ir complex C but also from the Ir complex A. The Ir complex C has a light emission spectrum having a peak at 620 nm, while the Ir complex A has a light emission spectrum having a peak at 610 nm. Since the difference of the peak wavelengths in the light emission spectra did not exceed 30 nm, the value on the CIE coordinates did not show any significant change.
[0081] The complex A had a quantum yield of 0.3 while the Ir complex C had a quantum yield of 0.66. The quantum yield was determined in the following manner:
[0000] Φ(sample)/Φ( st )=[ Sem (sample)/ Iabs (sample)]/[ Sem ( st )/ Iabs ( st )]
[0082] Φ (sample): quantum yield of measured sample
[0083] Φ (st): quantum yield of standard substance
[0084] Iabs(st): absorption coefficient at excitation wavelength of standard substance
[0085] Sem(st): area intensity of light emission spectrum of standard substance when excited at the same wavelength
[0086] Iabs(sample): absorption coefficient at excitation wavelength of measured sample
[0087] Sem(sample): area intensity of light emission spectrum of the measured sample when excited at the same wavelength.
[0088] The quantum yield Φ mentioned herein is represented by a relative value, taking Φ of the Ir complex G (to be explained later) as unity. Also labs was measured with a UV spectrophotometer (Shimadzu Mfg. Co.: UV3100), and Sem was measured with a fluorescent spectrophotometer (Hitachi Co.: F4500).
Example 2
[0089] A device was prepared by employing CBP as the host material of the light emitting layer, and doping the region of a thickness of 10 nm at the side of the hole transport layer within the light emitting layer of a thickness of 40 nm, with the Ir complex C as the light emitting material at a concentration of 7 wt. % and with the Ir complex A as the light emitting compound at a concentration of 3 wt. %, while co-evaporating the Ir complex C alone at a concentration of 7 wt. % in the remaining 30 nm region. The employed Ir complex A has a function of increasing the current in the device, thus also serving as the current enhancing material.
[0090] Table 2 shows the results of measurement of current and luminance of the above-described device and the device of the comparative example 11 under the application of a DC voltage of 10 V.
[0000]
TABLE 2
Current (mA/cm 2 )
Luminance (cd/m 2 )
Example 2
23.5
621
Comp. Ex. 11
11.8
426
[0091] The results in Table 2 confirm that the device of the example 2 showed an increase in the current and the luminance in comparison with the device of the comparative example 11, and that the light emitting compound, even in case of doping only a part of the light emitting layer, has an effect of increasing the current and the luminance. Following Tab. 3 shows the quantum yield and band gap of the Ir complex A and the Ir complex C. The Ir complex A has a larger band gap and a smaller quantum yield.
[0000]
TABLE 3
Quantum yield
Band gap
Ir complex A
0.3
2.02 eV
Ir complex C
0.66
2 eV
[0092] In the comparison of the examples 1 and 2, the light emission spectrum of the example 2 showed a weaker light emission from the Ir complex A and a higher proportion of the light emission from the Ir complex C in comparison with the example 1. This is because the injection of positive holes became easier by the current enhancing effect, whereby the electron-positive hole recombination and the light emission principally took place in the Ir complex C.
Example 3
[0093] In this example, there was employed a device configuration with a four-layered organic layer as shown in FIG. 1C . An ITO film (transparent electrode 14 ) of a thickness of 100 nm was patterned on a glass substrate (transparent substrate 15 ). On thus prepared ITO substrate, following organic layers and electrode layers were formed in succession by vacuum evaporation by resistance heating in a vacuum chamber of 10 −4 Pa:
[0000] Hole transport layer 13 (40 nm): FL03 (following chemical formula)
[0000]
[0000] Light emitting layer 12 (40 nm): host material+light emitting material 1 +light emitting material 2 Electron transport layer 17 (50 nm): Bphen (following chemical formula)
[0000]
[0000] Electron injection layer 16 (1 nm): KF
Metal electrode layer (100 nm): Al
It was so patterned that the electrodes had an opposed area of 3 mm 2 .
[0094] In forming the light emitting layer 12 , the Ir complex C was employed as the light emitting material 1 , and the Ir complex D was employed as the light emitting material 2 .
[0000]
[0095] The Ir complex C and the Ir complex D were measured in equal amounts and were agitated and mixed under crushing of the crystals in an agate mortar to obtain powder mixture.
[0096] Thus obtained powder mixture was charged in an evaporation boat and was subjected to co-evaporation with CBP as the host material. The co-evaporation with the host material was conducted in such a manner that the aforementioned mixture of the Ir complex C and the Ir complex D represented 7 wt. %.
[0097] The characteristics of thus prepared device are shown in the following table.
Comparative Example 31
[0098] A device was prepared utilizing only the Ir complex C of the light emitting material 1 as the light emitting material.
Comparative Example 32
[0099] A device was prepared utilizing only the Ir complex D of the light emitting material 2 as the light emitting material.
[0100] The results of evaluation of these devices are also shown in the following table.
[0000]
TABLE 4
Luminance
Characteristics at luminance
half-life
100 cd/m 2
(hr) from
Light
current
power
initial
emitting
voltage
efficiency
efficiency
value
material
(v)
(cd/A)
(lm/W)
1000 cd/m 2
Example 3
Ir complex
5.7
13.5
7.6
52
C +
Ir complex D
Comp.
Ir complex C
5
7.6
4.8
50
Ex. 31
Comp.
Ir complex D
7.5
6.8
2.9
5.4
Ex. 32
[0101] In the device of the present example, the drive voltage required for light emission at 100 cd/m 2 was 5.7 V, which was somewhat higher than 5 V in the comparative example 31 but was significantly lower than 7.5 V in the comparative example 32.
[0102] Also the current efficiency (measured in cd/A) was 13.5 cd/A, which was significantly higher than 7.6 cd/A in the comparative example 31 and 6.8 cd/A in the comparative example 32.
[0103] The situation was similar also in the power efficiency, and the device of the present example was very efficient with a power efficiency of 7.61 m/W which is significantly higher than 4.81 m/W in the comparative example 31 and 2.91 m/W in the comparative example 32.
[0104] Furthermore, the half life of the luminance in the continuous drive of the device from an initial luminance of 1000 cd/m 2 was 52 hours, corresponding to a significant improvement in comparison with 50 hours in the comparative example 31 and 5.4 hours in the comparative example 32. The half life of the luminance attained an improvement of more than 10 times in comparison with the comparative example 32, and is considered to represent a particularly large effect of the present invention.
[0105] In the present example, the Ir complex C has a quantum yield of 0.66 while the Ir complex D has a quantum yield of 0.92. The peak wavelength of light emission is 620 nm in the Ir complex C and 595 nm in the Ir complex D.
[0106] However, in case of employing an Ir complex I having a peak wavelength of light emission of 595 nm same as in the Ir complex D but having a lower quantum yield of 0.29, the light emission efficiency at the luminance of 300 cd/m 2 and the half life were inferior to those in the device employing the Ir complex D. It is therefore found desirable that the quantum yield of the light emitting material having a shorter wavelength of light emission is larger than that of the light emitting material having a longer wavelength of light emission.
[0000]
TABLE 5
Light emitting
Efficiency (300 cd/m 2 )
Half life
material
cd/A
(hours)
Ir complex C +
11.1
93
Ir complex D
Ir complex C +
8.3
18.2
Ir complex I
[0107] In the iridium complexes employed in the present example, the levels of the highest occupied molecular orbit (HOMO) and of the lowest unoccupied molecular orbit (LUMO) were as follows.
[0000]
TABLE 6
Ir complex C
Ir complex D
HOMO (eV)
−5.13
−5.32
LUMO (eV)
−2.47
−2.6
[0108] Both the HOMO level and the LUMO level were higher in the iridium complex C than in the iridium complex D.
[0109] The electron levels were determined, based on the measurement of oxidation-reduction potential by cyclic voltammetry (model: Electrochemical Interface SI 1287, Solartron Inc.) and the data of band gap measurement by optical absorption, by conversion with reference to the separately measured HOMO of the Ir complex C (model: AC-1, Riken Kiki Co.).
[0110] Then, FIG. 2 shows the photoluminescence (optically excited light emission spectra in dilute toluene solution) of the Ir complex C and the Ir complex D employed in the present example. The light emission spectra of these two compounds are mutually very close and mutually overlap in the principal portion of the spectra. The shift in color is not conspicuous because of the use of the light emitting materials having very close light emission wavelengths.
[0111] The Ir complex C and the Ir complex D, employed in the present example, have the evaporation temperature in vacuum of 267° C. and 234° C. respectively, and, in general, the evaporation temperature is lower in the iridium complex including fluorine atoms. One of the features of the present invention lies in a fact that the molecular flow in the evaporation process can be controlled (for example control of cluster size) by evaporating a mixture of light emitting materials of different evaporation temperatures from a same crucible.
[0112] Also the electric current supplied to the heating container, required for evaporation of the present example, was lower in the mixture, indicating a less thermal impact at the evaporation. These results are shown in the following table.
[0000]
TABLE 7
Efficiency
Boat current
Light emitting material
(cd/A)
(Amp)
Ir complex C
6.5
56.1
Ir complex C + Ir complex D
12.8
53.7
Comparative Example 33
[0113] Following table shows comparison with a case of evaporating the Ir complex C and the Ir complex D from different boats.
[0000]
TABLE 8
Evaporation
Characteristics at luminance 100 cd/m 2
of light
Current
Power
emitting
efficiency
efficiency
material
Voltage (V)
(cd/A)
(lm/W)
Example 3
same boat
5.7
13.5
7.6
Comp. ex. 33
different
5.5
9.6
5.8
boats
Comp. ex. 31
Ir complex
5
7.6
4.8
C only
[0114] In comparison with the case of evaporating the Ir complex C only, the current efficiency and the power efficiency were improved even in case of forming the mixed light emitting layer with the Ir complex D by evaporation from different boats. On the other hand, in the present example 3, in which the two complexes are mixed and evaporated from a same boat, the current efficiency and the power efficiency were improved in comparison with the comparative examples 31 and 33. This is presumably ascribable to a fact that the temperature at evaporation was lowered by the use of a mixture, thereby reducing the evaporation temperature and improving the film quality.
Comparative Example 34
[0115] As a next comparative example, a device was prepared by mixing and evaporating an Ir complex G (next structural formula) and the Ir complex C.
[0000]
[0116] The Ir complex G has a light emission peak at 514 nm, while the Ir complex C has a light emission peak at 620 nm, so that the light emission spectra show little overlapping as shown in FIG. 3 . In the present comparative example, the current efficiency and the power efficiency are inferior to those of the example 3. This fact indicates that the device characteristics can be improved if the overlapping portion of the light emission wavelength of each light emitting material is larger than the non-overlapping portion.
[0000]
TABLE 9
Characteristics at luminance 100 cd/m 2
Light
Current
Power
emitting
efficiency
efficiency
material
Voltage (V)
(cd/A)
(lm/W)
Comp. ex.
Ir complex C +
6.3
10.5
5.4
34
Ir complex G
Example 3
Ir complex C +
5.7
13.5
7.6
Ir complex D
Example 4
[0117] In this example, there was employed a device configuration with a four-layered organic layer as shown in FIG. 1C . An ITO film (transparent electrode 14 ) of a thickness of 100 nm was patterned on a glass substrate (transparent substrate 15 ).
[0118] On thus prepared ITO substrate, following organic layers and electrode layers were formed in succession by vacuum evaporation by resistance heating in a vacuum chamber of 10 −4 Pa. In the light emitting layer, there were used plural light emitting materials:
[0000] Hole transport layer 13 (40 nm): FL03
Light emitting layer 12 (40 nm): host material+light emitting material 1 +light emitting material 2 +light emitting material 3 +light emitting material 4 .
Electron transport layer 17 (50 nm): Bphen
Electron injection layer 16 (1 nm): KF
Metal electrode layer (100 nm): Al
It was so patterned that the electrodes had an opposed area of 3 mm 2 .
[0119] In the present example, the Ir complex C was employed as the light emitting material 1 , and the Ir complex D was employed as the light emitting material 2 . An Ir complex E (following structural formula) was employed as the light emitting material 3 :
[0000]
[0120] Also an Ir complex F (following structural formula) was employed as the light emitting material 4 :
[0000]
[0121] The Ir complexes C, D, E and F were mixed in a ratio of 3:1:2.5:3.5 to obtain a powder mixture. Thus obtained powder mixture was charged in an evaporation boat and co-evaporated with CBP as the host material. The film formation was so executed that the above-mentioned Ir complex mixture represented 7 wt. % of the host material. The characteristics of thus prepared device are shown in the following table 10, together with the evaluation results thereof.
[0000]
TABLE 10
Luminance
Characteristics at luminance
half life
100 cd/m 2
(hr) at
Light
Current
Power
initial
emitting
Voltage
efficiency
efficiency
luminance
material
(V)
(cd/A)
(lm/W)
1000 cd/m 2
Example 4
Ir
4.2
11.7
8
116
complexes
C, D, E, F
Comp.
Ir
5
7.6
4.8
50
ex. 31
complex C
Comp.
Ir
7.5
6.8
2.9
5.4
ex. 32
complex D
[0122] In the device of the present example, the drive voltage required for light emission at 100 cd/m 2 was 4.2 V, which corresponds to a significant improvement in comparison with 5 V in the comparative example 31 and 7.5 V in the comparative example 32. Also the current efficiency (measured in cd/A) was 11.7 cd/A, which was significantly higher than 7.6 cd/A in the comparative example 31 and 6.8 cd/A in the comparative example 32. The situation was similar also in the power efficiency, whereby a highly efficient device could be obtained.
[0123] Furthermore, the half life of the luminance in the continuous drive of the device from an initial luminance of 1000 cd/m 2 was 116 hours, corresponding to a significant improvement in comparison with 50 hours in the comparative example 31 and 5.4 hours in the comparative example 32. The half life of the luminance attained an improvement of from 2 to over 20 times in comparison with the comparative example, and is considered to represent a particularly large effect of the present invention.
[0124] Also the electric current supplied to the evaporation boat of the present example was lower in the mixture, indicating a lower temperature at the film formation of the light emitting layer and a less thermal damage. These results are shown in the following table.
[0000]
TABLE 11
Light emitting material
Boat current (Amp)
Ir complex C
56.1
Ir complexes C, D, E, F
55.7
Example 5
[0125] In this example, there was employed a device configuration with a three-layered organic layer as shown in FIG. 1B . An ITO film (transparent electrode 14 ) of a thickness of 100 nm was patterned on a glass substrate (transparent substrate 15 ).
[0126] On thus prepared ITO substrate, following organic and electrode layers were formed in succession by vacuum evaporation by resistance heating in a vacuum chamber of 10 −4 Pa.
[0000] Hole transport layer 13 (40 nm): FL03
Light emitting layer 12 (40 nm): host material+light emitting material 1 +light emitting material 2
Electron transport layer 17 (50 nm): Bphen
Metal electrode layer (100 nm): Al
It was so patterned that the electrodes had an opposed area of 3 mm 2 .
[0127] In the present example, a compound C (abbreviated as DCM) was employed as the light emitting material 1 .
[0000]
[0128] As the light emitting material 1 , there may also be employed a compound D represented by the following structural formula:
[0000]
[0129] The light emitting material 2 was composed of the aforementioned Ir complex C.
[0130] The compound C and the Ir complex C were measured in equal amounts and were agitated and mixed under crushing of the crystals in an agate mortar to obtain powder mixture. Thus obtained powder mixture was charged in an evaporation boat and was subjected to co-evaporation with CBP as the host material.
[0131] The co-evaporation with the host material was conducted in such a manner that the aforementioned mixture of the compound C and the Ir complex C represented 7 wt. %.
Example 6
[0132] In this example, there was employed a device configuration with a three-layered organic layer as shown in FIG. 1B . An ITO film (transparent electrode 14 ) of a thickness of 100 nm was patterned on a glass substrate (transparent substrate 15 ). On thus prepared ITO substrate, following organic and electrode layers were formed in succession by vacuum evaporation by resistance heating in a vacuum chamber of 10 −4 Pa:
[0000] Hole transport layer 13 (40 nm): FL03
Light emitting layer 12 (40 nm): host material+light emitting material 1 +light emitting material 2
Electron transport layer 17 (50 nm): Bphen
Electron transport/injection layer 16 (1 nm): KF
Metal electrode layer (100 nm): Al
It was so patterned that the electrodes had an opposed area of 3 mm 2 .
[0133] In the present example, the Ir complex C was employed as the light emitting material 1 , and an Ir complex H (following structural formula) was employed as the light emitting material 2 :
[0000]
[0134] The Ir complex C and the Ir complex H were measured in equal amounts and were agitated and mixed under crushing of the crystals in an agate mortar to obtain powder mixture. Thus obtained powder mixture was charged in an evaporation boat and was subjected to co-evaporation with CBP as the host material.
[0135] The co-evaporation with the host material was conducted in such a manner that the aforementioned mixture of the Ir complexes represented 7 wt. %.
Comparative Example 61
[0136] A device was prepared utilizing the Ir complex C only as the light emitting material, and executing co-evaporation with the host material in such a manner that the light emitting material represented 7 wt. %.
Comparative Example 62
[0137] A device was prepared utilizing the Ir complex H only as the light emitting material, and executing co-evaporation with the host material in such a manner that the light emitting material represented 7 wt. %.
[0138] The results of evaluation of these devices are shown in the following table.
[0000]
TABLE 12
Luminance
Characteristics at luminance
half life
100 cd/m 2
(hr) at
Light
Current
Power
initial
emitting
Voltage
efficiency
efficiency
luminance
material
(V)
(cd/A)
(lm/W)
1000 cd/m 2
Example 6
Ir complex
5.7
10.5
5.9
80
C +
Ir complex H
Comp. ex.
Ir complex C
5
7.6
4.8
50
61
Comp. ex.
Ir complex H
5.8
16.2
8.8
1.5
62
[0139] In the device of the present example, the drive voltage required for light emission at 100 cd/m 2 was 5.7 V, which was somewhat higher than 5 V in the comparative example 61 but was significantly lower than 5.8 V in the comparative example 62. Also the current efficiency was 10.5 cd/A, which corresponds to a significant improvement in comparison with 7.6 cd/A in the comparative example 61. The situation was similar also in the power efficiency, and the device of the present example was very efficient with a power efficiency of 5.91 m/W in comparison with 4.81 m/W in the comparative example 61.
[0140] Furthermore, the half life of the luminance in the continuous drive of the device from an initial luminance of 1000 cd/m 2 was 80 hours, corresponding to a significant improvement in comparison with 50 hours in the comparative example 61 and 1.5 hours in the comparative example 62.
[0141] The present example was inferior to the comparative example 62 in the current efficiency and the power efficiency, but was improved in the light emission color toward red in comparison with the comparative example 62. More specifically, the present example had CIE coordinate values of (0.68, 0.33) in comparison with the values (0.65, 0.35) of the comparative example 62. The values of light emission of the comparative example 61 were (0.68, 0.33) and were almost same as those of the present example. The half life of the luminance attained an improvement of more than 10 times in comparison with the comparative example 62, and is considered to represent a particularly large effect of the present invention.
[0142] In the iridium complexes employed in the present example, and the HOMO level of the Ir complex C was −5.13 eV and was higher than the HOMO level of −5.19 eV of the Ir complex H.
[0143] On the other hand, the LUMO level of the Ir complex C was −2.47 eV and was higher than the LUMO level of −2.6 eV of the Ir complex H.
[0144] The Ir complex C and the Ir complex H, employed in the present example, have the evaporation temperature in vacuum of 267° C. and 230° C. respectively, and, in general, the evaporation temperature is lower in the iridium complex including fluorine atoms. One of the features of the present invention lies in a fact that the evaporation temperature can be lowered and the cluster size can be made smaller at the evaporation by evaporating a mixture of light emitting materials of different evaporation temperatures from a same crucible.
[0145] Also the electric current supplied to the evaporation boat was lower in the mixture, indicating a less thermal deterioration at the device preparation.
[0146] These results are shown in the following table.
[0000]
TABLE 13
Efficiency
Boat current
Light emitting material
(cd/A)
(Amp)
Ir complex C
6.5
56.1
Ir complex C + Ir complex H
10
52.6
Example 7
[0147] In this example, there was employed a device configuration with a four-layered organic layer as shown in FIG. 1C , with conditions described in the example 1.
[0148] A device was prepared by employing CBP as the host material and doping the light emitting layer with the Ir complex B as the light emitting material at a concentration of 7 wt. % and with the compound A as the non-light emitting compound at a concentration of 3 wt. %. The employed compound A has a function of increasing the current in the device, thus also serving as the current enhancing material.
Comparative Example 71
[0149] A device was prepared as in the example 7, except that the doping with the compound A was not executed.
[0150] Following table shows the results of measurement of current and luminance of these devices under the application of a DC voltage of 10 V.
[0000]
TABLE 14
Current (mA/cm 2 )
Luminance (cd/m 2 )
Example 7
50.1
386
Comp. Ex. 71
36.3
312
[0151] Table 14 indicates that the device of the example 7 showed increases in the current and in the luminance in comparison with that of the comparative example 71, thus confirming the effect of addition of the non-light emitting compound and the effect as the current enhancing material thereof. The light emission spectrum was almost same for the example 7 and the comparative example 71, and the light emission was observed only from the Ir complex B.
Example 8
[0152] A device was prepared by employing TAZ as the host material and doping the light emitting layer with CBP as the non-light emitting compound at a concentration of 10 wt. % and with the Ir complex B as the light emitting material at a concentration of 7 wt. %. The employed CBP has a function of increasing the current in the device, thus also serving as the current enhancing material.
Comparative Example 81
[0153] A device was prepared as in the example 8, except that the doping with CBP was not executed.
[0154] Following table shows the results of measurement of current and luminance of these devices under the application of a DC voltage of 10 V.
[0000]
TABLE 15
Current (mA/cm 2 )
Luminance (cd/m 2 )
Example 8
6.56
140
Comp. Ex. 81
3.18
99.4
[0155] Table 15 indicates that the device of the example 8 showed increases in the current and in the luminance in comparison with that of the comparative example 81, thus confirming the effect of addition of the non-light emitting compound and the effect as the current enhancing material thereof. The light emission spectrum was almost same for the example 8 and the comparative example 81, and the light emission was observed only from the Ir complex B.
[0156] CBP has a band gap of 2.5 to 3.0 eV, which is larger than that of 2 eV of the Ir complex B.
Example 9
[0157] There was prepared a device similar to that of the example 3 except for the configuration of the light emitting layer. The light emitting layer was composed of a mixture of a host material, a light emitting material and a non-light emitting compound.
[0158] In the present example, the Ir complex C including phenylisoquinoline as the ligand was employed as the light emitting material, and a compound 3 (following structural formula) was employed as the non-light emitting compound:
[0000]
[0159] The Ir complex C and the compound 3 were measured in equal amounts and were agitated and mixed under crushing of the crystals in an agate mortar to obtain powder mixture. Thus obtained powder mixture was charged in an evaporation boat and was subjected to co-evaporation with CBP as the host material which was charged in another evaporation boat. The co-evaporation of the mixture of the Ir complex C with the host material was conducted in such a manner that the aforementioned mixture of the compound C represented 20 wt. %.
[0160] The electric current supplied to the heating container at the evaporation of the mixture of the present example was found to be lower, whereby the evaporation temperature could be significantly reduced. This fact alleviated the thermal damage at the preparation of the device, thereby enabling stable preparation of the device.
[0161] The HOMO and LUMO levels of the iridium complex and the compound 3 employed in the present example are shown in the following table.
[0000]
TABLE 16
Ir complex C
Compound 3
HOMO
−5.13
−5.38
LUMO
−2.47
−1.94
Band gap
2.66
3.44
[0162] It will be understood that the Ir complex C constituting the light emitting material has a band gap narrower than that of the non-light emitting compound 3.
Example 10
[0163] There was prepared a device similar to that of the example 3 except for the configuration of the light emitting layer. The light emitting layer was composed of a mixture of a host material, a light emitting material and a non-light emitting compound.
[0164] In the present example, the compound C was employed as the light emitting material, and the aforementioned compound 3 was employed as the non-light emitting compound.
[0165] The compound C and the compound 3 were measured in equal amounts and were agitated and mixed under crushing of the crystals in an agate mortar to obtain powder mixture. Thus obtained powder mixture was charged in an evaporation boat and was subjected to co-evaporation with CBP as the host material. The co-evaporation was conducted in such a manner that the mixture of the compound C and the compound 3 represented 7 wt. %.
Example 11
Comparative Example 71
[0166] In this example, there was employed a device configuration with a four-layered organic layer as shown in FIG. 10 , and the conditions described in the example 1 were employed for the device configuration other than the light-emitting layer.
[0167] A device was prepared by employing CBP as the host material and doping the light emitting layer with the Ir complex B as the light emitting material at a concentration of 7 wt. % and with PBD represented by the following structural formula as the current enhancing material at a concentration of 3 wt. %.
[0168] Also a device was prepared as in the example 11, except that the doping with PBD was not executed (comparative example 71).
[0000]
[0169] Following table shows the results of measurement of current and luminance of these devices under the application of a DC voltage of 10 V.
[0000]
TABLE 17
Current (mA/cm 2 )
Luminance (cd/m 2 )
Example 11
62
450
Comp. Ex. 71
36.3
312
[0170] Table 17 indicates that the device of the example 11 showed increases in the current and in the luminance in comparison with that of the comparative example 71, thus confirming the effect of the current enhancing material. The light emission spectrum was almost same for the example 11 and the comparative example 71, and the light emission was observed only from the Ir complex B.
[0171] In this case, the host material CBP has a strong hole transporting property, and doping with an electron transporting material such as PBD is effective for increasing the device current.
[0172] As the current enhancing material employable in the present invention, there may also be employed, for example, an electron transporting material such as PySPy represented by the following structural formula, but such example is not restrictive.
[0000]
Example 12
Comparative Example 81
[0173] In this example, there was employed a device configuration with a four-layered organic layer as shown in FIG. 1C , and the conditions described in the example 1 were adopted in the device configuration other than the light emitting layer.
[0174] A device was prepared by employing TAZ as the host material and doping the light emitting layer with the Ir complex B as the light emitting material at a concentration of 7 wt. % and with NPD represented by the following structural formula as the current enhancing material at a concentration of 3 wt. %.
[0175] Also a device was prepared as in the example 12, except that the doping with NPD was not executed. This configuration was same as that of the comparative example 81.
[0000]
[0176] Following table shows the results of measurement of current and luminance of these devices under the application of a DC voltage of 10 V.
[0000]
TABLE 18
Current (mA/cm 2 )
Luminance (cd/m 2 )
Example 12
82
180
Comp. Ex. 81
3.18
99.4
[0177] Table 18 indicates that the device of the example 12 showed increases in the current and in the luminance in comparison with that of the comparative example 81, thus confirming the effect of the current enhancing material. The light emission spectrum was almost same for the example 12 and the comparative example 81, and the light emission was observed only from the Ir complex B.
[0178] In this case, since the host material TAZ is an electron transporting material, doping with a hole transporting material such as NPD is effective as the current enhancing material.
[0179] As the current enhancing material employable in the present invention, there may also be employed, for example, a hole transporting material such as m-MTDATA represented by the following structural formula, but such example is not restrictive.
[0000]
[0180] In the foregoing examples, there have been explained cases employing a host material, but the present invention provides similar effects also in a case not including the host material.
[0181] In summary of the foregoing results, the luminance, efficiency and life time of the light emission were improved in comparison with a case not including the non-light emitting compound.
POSSIBILITY OF INDUSTRIAL APPLICATION
[0182] As explained in the foregoing, the present invention enables to increase the current flowing in a light emitting device, to drive such device with a lower voltage, and to improve the luminance and the light emission efficiency.
[0183] The highly efficient light emitting device of the present invention is applicable to products requiring energy saving or a high luminance. Examples of such application include a display apparatus, an illumination apparatus, a light source of a printer and a back light of a liquid crystal display. In the application to the display apparatus, there can be realized a flat panel display of a low energy consumption, high visibility and a light weight. Also in the application to the light source of a printer, the laser light source currently employed in the laser beam printer can be replaced by the light emitting device of the present invention. In such case, an image is formed by arranging independently addressable elements in an array and by giving an exposure of a desired form to a photosensitive drum. The use of the device of the present invention allows to significantly reduce the volume of the entire apparatus. Also in the illumination apparatus or in the back light, there can be expected the energy saving effect of the present invention.
|
A light emitting device comprises a pair of electrodes and an organic light emitting layer between the electrodes. The organic light emitting layer includes a host material, a first phosphorescent dopant, and a second dopant different from the first phosphorescent dopant. The amount of the second dopant is greater than the amount of the first dopant in the organic light emitting layer. The host material, the first phosphorescent dopant and the second dopant are mixed throughout the organic light emitting layer.
| 8
|
TECHNICAL FIELD
The present invention relates to production of organic compounds, particularly polyoxymethylene dimethyl ethers, which are suitable components for blending into fuel having improved qualities for use in diesel engines. More specifically, it relates to employing a heterogeneous, condensation promoting catalyst capable of hydrating dimethyl ether in conversion of dimethyl ether and formaldehyde to form a condensation effluent. A dimethyl ether-free mixture, separated form the effluent, is heated in a catalytic distillation column to convert methanol and formaldehyde present to methylal and higher polyoxymethylene dimethyl ethers and separate the methylal from the higher polyoxymethylene dimethyl ethers. Advantageously, the catalytic distillation column has a section containing an anion exchange resin whereby an essentially acid-free product is obtained which can be used directly as a blending component, or fractionated, as by further distillation, to provide more suitable components for blending into diesel fuel.
This integrated process also provides its own source of formaldehyde which is an un-purified liquid stream derived from a mixture formed by oxidative dehydrogenation (oxy-dehydrogenation) of dimethyl ether using a catalyst based silver as an essential catalyst.
BACKGROUND OF THE INVENTION
Conversion of low molecular weight alkanes such as methane to synthetic fuels or chemicals has received increasing attention because low molecular weight alkanes are generally available from secure and reliable sources. For example, natural gas wells and oil wells currently produce vast quantities of methane. Reported methods for converting low molecular weight alkanes to more easily transportable liquid fuels and chemical feedstocks can be conveniently categorized as direct oxidative routes and/or as indirect syngas routes. Direct oxidative routes convert lower alkanes to products such as methanol, gasoline, and relatively higher molecular weight alkanes. In contrast, indirect syngas routes typically involve production of synthesis gas as an intermediate product.
Routes are known for converting methane to dimethyl ether. For example, methane is steam reformed to produce synthesis gas. Thereafter, dimethyl ether and methanol can be manufactured simultaneously from the synthesis gas, as described in U.S. Pat. No. 4,341,069 issued to Bell et al. They recommend a dimethyl ether synthesis catalyst having copper, zinc, and chromium co-precipitated on a gamma-alumina base. Alternatively, methane is converted to methanol, and dimethyl ether is subsequently manufactured from methanol by passing a mixed vapor containing methanol and water over an alumina catalyst, as described in an article by Hutchings in New Scientist (Jul. 3, 1986) 35.
Formaldehyde is a very important intermediate compound in the chemical industry. The extreme reactivity of the formaldehyde carbonyl group and the nature of the molecule as a basic building block has made formaldehyde an important feedstock for a wide variety of industrially important chemical compounds. Historically, formaldehyde has found its largest volume of application in the manufacture of phenol-formaldehyde resins, urea-formaldehyde resins and other polymers. Pure formaldehyde is quite uncommon since it polymerizes readily. It was usually obtained as an aqueous solution such as formalin, which contains only about 40 percent formaldehyde. However, more recently, formaldehyde is usually transported as an item of commerce in concentrations of 37 to 50 percent by weight. A solid source of formaldehyde called paraformaldehyde is also commercially available.
Because of the reactivity of formaldehyde, its handling and separation require special attention. It is a gas above -19° C. and is flammable or explosive in air at concentrations of about 7 to about 12 mol percent. Formaldehyde polymerizes with itself at temperatures below 100° C. and more rapidly when water vapor or impurities are present. Since formaldehyde is usually transported in aqueous solutions of 50 percent by weight or lower concentration, producers have tended to locate close to markets and to ship the methanol raw material, which has a smaller volume.
It is known that some reactions may be carried out by means of catalytic distillation. In catalytic distillation, reaction and separation are carried out simultaneously in a distillation column with internal and/or external stages of contact with catalyst.
In U.S. Pat. No. 4,215,011, Smith, Jr. discloses a method for the separation of an isoolefin, preferably having four to six carbon atoms, from streams containing mixtures thereof with the corresponding normal olefin, wherein the mixture is fed into a reaction-distillation column containing a fixed-bed, acidic cation exchange resin and contacted with the acidic cation exchange resin to react the isoolefin with itself to form a dimer and the dimer is separated from the normal olefin, the particulate catalytic material, i.e., the acidic cation exchange resin, being contained in a plurality of closed cloth pockets, which pockets are arranged and supported in the column by wire mesh.
In U.S. Pat. No. 4,443,559, Smith, Jr. discloses a catalytic distillation structure which comprises a catalyst component associated intimately with or surrounded by a resilient component, which component is comprised of at least 70 vol. percent open space for providing a matrix of substantially open space. Examples of such resilient component are open-mesh, knitted, stainless wire (demister wire or an expanded aluminum); open-mesh, knitted, polymeric filaments of nylon, Teflon, etc.; and highly-open structure foamed material (reticulated polyurethane).
In U.S. Pat. No. 5,113,015, David A. Palmer, K. D. Hansen and K. A. Fjare disclose to a process for recovering acetic acid from methyl acetate wherein the methyl acetate is hydrolyzed to methanol and acetic acid via catalytic distillation.
In German Democratic Republic DD 245 868 A1 published May 20, 1987 in the text submitted by the applicant, preparation of methylal is carried out by reaction of methanol with trioxane, formalin or paraformaldehyde in the presence of a specific zeolite. Autoclave reactions of 1 to 8 hours are described using a zeolite of the "LZ40 type" with a ratio of silicon dioxide to alumina ratio of 78 at temperatures from 493 to 543 K. Methylal content of the product as high as 99.8 percent (without methanol) is reported for trioxane at 523 K for 3 hours. Reaction pressures did not exceed 5 MPa in the autoclave. Neither conversions nor selectivity are reported.
In U.S. Pat. No. 4,967,014, Junzo Masamoto, Junzo Ohtake and Mamoru Kawamura describe a process for formaldehyde production by reacting methanol with formaldehyde to form methylal, CH 3 OCH 2 OCH 3 , and then oxidizing the resulting methylal to obtain formaldehyde. In the methylal formation step, a solution containing methanol, formaldehyde and water was brought into solid-liquid contact with a solid acid catalyst, and a methylal-rich component was recovered as a distillate. This process employs reactive distillation performed using a distillation column and multireaction units. The middle portion of the distillation column was furnished with stages from which the liquid components were withdrawn and pumped to the reactor units, which contained solid acid catalyst. The reactive solutions containing the resulting methylal were fed to the distillation column, where methylal was distilled as the overhead product.
Polyoxymethylene dimethyl ethers are the best known members of the dialkyl ether polymers of formaldehyde. While diethyl and dipropyl polyoxymethylene ethers have been prepared, major attention has been given to the dimethyl ether polymers. Polyoxymethylene dimethyl ethers make up a homologous series of polyoxymethylene glycol derivatives having the structure represented by use of the type formula indicated below:
CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3
Chemically, they are acetals closely related to methylal, CH 3 OCH 2 OCH 3 , which may be regarded as the parent member of the group in which n of the type formula equals 1. They are synthesized by the action of methanol on aqueous formaldehyde or polyoxymethylene glycols in the presence of an acidic catalyst just as methylal is produced. On hydrolysis they are converted to formaldehyde and methanol. Like other acetals, they possess a high degree of chemical stability. They are not readily hydrolyzed under neutral or alkaline conditions, but are attacked by even relatively dilute acids. They are more stable than the polyoxymethylene diacetates.
Due to the relatively small differences in the physical properties (melting points, boiling points, and solubility) of adjacent members in this series, individual homologs are not readily separated. However, fractions having various average molecular weight values have been isolated. The normal boiling point temperature of a fraction having average n of 2 in the type formula is reported as 91° to 93° C. Boiling points at atmospheric pressure calculated from partial pressure equations range from 105.0° C. for n of 2, to 242.3° C. for n of 5. (Walker, Joseph Frederic, "Formaldehyde", Robert E. Krieger Publishing Co., issued as No. 159 of American Chemical Society Monograph series (1975), pages 167-169)
Polyoxymethylene dimethyl ethers are prepared in laboratory scale by heating polyoxymethylene glycols or paraformaldehyde with methanol in the presence of a trace of sulfuric or hydrochloric acid in a sealed tube for 15 hours at 150° C., or for a shorter time (12 hours) at 165° to 180° C. Considerable pressure is caused by decomposition reactions, which produce carbon oxides, and by formation of some dimethyl ether. The average molecular weight of the ether products increases with the ratio of paraformaldehyde or polyoxymethylene to methanol in the charge. A high polymer is obtained with a 6 to 1 ratio of formaldehyde (as polymer) to methanol. In these polymers, the n value of the type formula CH 3 O(CH 2 O) n CH 3 is greater than 100, generally in the range of 300 to 500. The products are purified by washing with sodium sulfite solution, which does not dissolve the true dimethyl ethers, and may then be fractionated by fractional crystallization from various solvents.
U.S. Pat. No. 2,449,469 in the names of W. F. Gresham and R. E. Brooks reported obtaining good yields of polyoxymethylene dimethyl ethers containing 2 to 4 formaldehyde units per molecule. This procedure is carried out by heating methylal with paraformaldehyde or concentrated formaldehyde solutions in the presence of sulfuric acid.
In the past, various molecular sieve compositions, natural and synthetic, have been found to be useful for a number of hydrocarbon conversion reactions. Among these are alkylation, aromatization, dehydrogenation and isomerization. Among the sieves which have been used are Type A, X, Y and those of the MFI crystal structure as shown in "Atlas of Zeolite Structure Types," Second Revised Edition, 1987, published on behalf of the Structure Commission of the International Zeolite Associates and incorporated by reference herein. Representative of the last group are ZSM-5 and AMS borosilicate molecular sieves.
Prior art developments have resulted in the formation of many synthetic crystalline materials. Crystalline aluminosilicates are the most prevalent and, as described in the patent literature and in the published journals, are designated by letters or other convenient symbols. Exemplary of these materials are Zeolite A (Milton, in U.S. Pat. No. 2,882,243), Zeolite X (Milton, in U.S. Pat. No. 2,882,244), Zeolite Y (Breck, in U.S. Pat. No. 3,130,007), Zeolite ZSM-5 (Argauer, et al., in U.S. Pat. No. 3,702,886), Zeolite ZSM-11 (Chu, in U.S. Pat. No. 3,709,979), Zeolite ZSM-12 (Rosinski, et al., in U.S. Pat. No. 3,832,449), and others.
It is well known that internal combustion engines have revolutionized transportation following their invention during the last decades of the 19th century. While others, including Benz and Gottleib Wilhelm Daimler, invented and developed engines using electric ignition of fuel such as gasoline, Rudolf C. K. Diesel invented and built the engine named for him which employs compression for autoignition of the fuel in order to utilize low-cost organic fuels. Development of improved diesel engines for use in automobiles has proceeded hand-in-hand with improvements in diesel fuel compositions, which today are typically derived from petroleum. Modern high performance diesel engines demand ever more advanced specification of fuel compositions, but cost remains an important consideration.
Even in newer, high performance diesel engines combustion of conventional fuel produces smoke in the exhaust. Oxygenated compounds and compounds containing few or no carbon-to-carbon chemical bonds, such as methanol and dimethyl ether, are known to reduce smoke and engine exhaust emissions. However, most such compounds have high vapor pressure and/or are nearly insoluble in diesel fuel, and they have poor ignition quality, as indicated by their cetane numbers. Furthermore, other methods of improving diesel fuels by chemical hydrogenation to reduce their sulfur and aromatics contents, also causes a reduction in fuel lubricity. Diesel fuels of low lubricity may cause excessive wear of fuel injectors and other moving parts which come in contact with the fuel under high pressures.
Recently, U.S. Pat. No. 5,746,785 in the names of David S. Moulton and David W. Naegeli reported blending a mixture of alkoxy-terminated poly-oxymethylenes, having a varied mixture of molecular weights, with diesel fuel to form an improved fuel for autoignition engines. Two mixtures were produced by reacting paraformaldehyde with (i) methanol or (ii) methylal in a closed system for up to 7 hours and at a temperatures of 150° to 240° C. and pressures of 300 psi to 1,000 psi to form a product containing methoxy-terminated poly-oxymethylenes having a molecular weight of from about 80 to about 350 (polyoxymethylene dimethyl ethers). More specifically, a 1.6 liter cylindrical reactor was loaded with a mixture of methanol and paraformaldehyde, in molar ratio of about 1 mole methanol to 3 moles paraformaldehyde, and in a second preparation, methylal (dimethoxymethane) and paraformaldehyde were combined in a molar ratio of about 1 mole methylal to about 5 moles paraformaldehyde. In the second procedure, a small amount of formic acid, about 0.1 percent by weight of the total reactants, was added as a catalyst. The same temperatures, pressures and reaction times are maintained as in the first. Disadvantages of these products include the presence of formic acid and thermal instability of methoxy-terminated polyoxymethylenes under ambient pressure and acidic conditions.
There is, therefore, a present need for catalytic processes to prepare oxygenated organic compounds, particularly polyoxymethylene dimethyl ethers, which do not have the above disadvantages. An improved process should be carried out advantageously in the liquid phase using a suitable condensation-promoting catalyst system, preferably a molecular sieve based catalyst which provides improved conversion and yield. Such an improved process which converts lower value compounds to higher polyoxymethylene dimethyl ethers would be particularly advantageous. Dimethyl ether is, for example, less expensive to produce than methanol on a methanol equivalent basis, and its condensation to polyoxymethylene dimethyl ethers does not produce water as a co-product.
The base diesel fuel, when blended with such mixtures in a volume ratio of from about 2 to about 5 parts diesel fuel to 1 part of the total mixture, is said to provide a higher quality fuel having significantly improved lubricity and reduced smoke formation without degradation of the cetane number or smoke formation characteristics as compared to the base diesel fuel.
This invention is directed to overcoming the problems set forth above in order to provide Diesel fuel having improved qualities. It is desirable to have a method of producing a high quality diesel fuel that has better fuel lubricity than conventional low-sulfur, low-aromatics diesel fuels, yet has comparable ignition quality and smoke generation characteristics. It is also desirable to have a method of producing such fuel which contains an additional blended component that is soluble in diesel fuel and has no carbon-to-carbon bonds. Furthermore, it is desirable to have such a fuel wherein the concentration of gums and other undesirable products is reduced.
SUMMARY OF THE INVENTION
Economical processes are disclosed for production of a mixture of oxygenated organic compounds which are suitable components for blending into fuel having improved qualities for use in compression ignition internal combustion engines (diesel engines).
According to the present invention, there is now provided a continuous process for catalytic production of oxygenated organic compounds, particularly polyoxymethylene dimethyl ethers. More specifically, continuous processes of this invention include contacting a source of formaldehyde and a predominately dimethyl ether feedstream comprising dimethyl ether and methanol with a condensation promoting catalyst capable of hydrating dimethyl ether, in a form which is heterogeneous to the feedstream, under conditions of reaction sufficient to form an effluent of the condensation comprising water, methanol, formaldehyde, dimethyl ether, one or more polyoxymethylene dimethyl ethers having a structure represented by the type formula
CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3
in which formula n is a number from 1 to about 10.
For this aspect of the invention, suitable condensation-promoting catalysts include at least one member of the group consisting of molecular sieves. A preferred class of molecular sieve is crystalline metallosilicates exhibiting the MFI crystal structure, such as crystalline aluminosilicates and crystalline borosilicates. More preferably the molecular sieve is crystalline aluminosilicate exhibiting the MFI crystal structure with a silicon-to-aluminum atomic ratio of at least 10, or the molecular sieve is crystalline borosilicate exhibiting the MFI crystal structure, and has the following compositions in terms of mole ratios of oxides:
0.9±0.2 M.sub.2 /.sub.n O:B.sub.2 O.sub.3 :Y SiO.sub.2 :Z H.sub.2 O,
wherein M is at least one cation having a valence of n, Y is between 4 and about 600, and Z is between 0 and about 160.0.
In another aspect, this invention provides continuous processes which further comprise fractionating the effluent of the condensation to obtain an overhead stream which is predominantly dimethyl ether, and an essentially dimethyl ether-free bottom stream comprising formaldehyde, methanol and at least methylal. Preferably at least a portion of the overhead stream containing dimethyl ether is recycled to contacting with the condensation-promoting catalyst.
According to a further aspect of this invention, the essentially dimethyl ether-free bottom stream comprising formaldehyde, methanol and at least methylal is heated with an acidic catalyst, which is heterogeneous to the feedstream, under conditions of reaction sufficient to convert formaldehyde and methanol present to methylal and higher polyoxymethylene dimethyl ethers.
Preferably, the heating of the bottom stream with the acidic catalyst employs at least one catalytic distillation column with internal and/or external stages of contact with the acidic catalyst, and internal zones to separate the methylal from the higher polyoxymethylene dimethyl ethers.
Suitable acidic catalysts include at least one member of the group consisting of bentonites, montmorillonites, cation-exchange resins, and sulfonated fluoroalkylene resin derivatives, preferably comprises a sulfonated tetrafluoroethylene resin derivative. A preferred class of acidic catalysts comprises at least one cation-exchange resin of the group consisting of styrene-divinylbenzene copolymers, acrylic acid-divinylbenzene copolymers, and methacrylic acid-divinylbenzene copolymers. Preferably, the heating of the bottom stream with the acidic catalyst employs at least one distillation column with internal and/or external stages of contact with the acidic catalyst.
Advantageously, the mixture of polyoxymethylene dimethyl ethers is contacted with an anion exchange resin to form an essentially acid-free mixture. Contacting with the anion exchange resin is preferably carried out within a section of the catalytic distillation column below the stages of contact with the acidic catalyst to form an essentially acid-free mixture.
In a preferred embodiment of the invention the essentially acid-free mixture of polyoxymethylene dimethyl ethers is fractionated within a section of the distillation column below the stages of contact with the acidic catalyst to provide an aqueous side-stream which is withdrawn from the distillation column, and an essentially water-free mixture of higher molecular weight polyoxymethylene dimethyl ethers (values of n greater 1) which is withdrawn from the distillation column near its bottom. Advantageously, at least a portion of the aqueous side-stream is used for recovery of an aqueous formaldehyde solution in an adsorption column.
In another aspect, this invention is an integrated process wherein the source of formaldehyde is formed by a process comprising continuously contacting a gaseous feedstream comprising dimethyl ether, dioxygen and diluent gas with a catalytically effective amount of an oxidative dehydrogenation promoting catalyst comprising silver as an essential catalyst component at elevated temperatures to form a gaseous mixture comprising formaldehyde, methanol, dioxygen, diluent gas, carbon dioxide and water vapor; cooling the gaseous dehydrogenation mixture with an adsorption liquid and adsorbing formaldehyde therein; and separating the resulting liquid source of formaldehyde from a mixture of gases comprising dioxygen, diluent, carbon monoxide, carbon dioxide and water vapor.
At least a portion of the mixture of gases separated the resulting aqueous source of formaldehyde is recycled into the gaseous feedstream.
Preferably the formaldehyde formed is recovered as an aqueous solution containing less than about 60 percent water, preferably less than about 50 percent water and more preferably less than about 25 percent water by using at least one continuous adsorption column with cooling to temperatures in a range downward from about 100° C. to 25° C.
Suitable sources of dioxygen are air or a dioxygen-enriched gas stream obtained by physically separating a gaseous mixture containing at least about 10 volume percent dioxygen into a dioxygen-depleted stream and a dioxygen-enriched gas stream. Preferably the gaseous mixture contains at least 60 volume percent dinitrogen and wherein the dioxygen-enriched gas stream comprises a volume ratio of dinitrogen to dioxygen of less than 2.5 to 1.
For this aspect of the invention, suitable oxidative dehydrogenation promoting catalyst comprises silver and optionally up to about 8 percent by weight of a compound selected from the group consisting of oxides of boron, phosphorous, vanadium, selenium, molybdenum and bismuth, phosphoric acid, ammonium phosphate and ammonium chloride.
For a more complete understanding of the present invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawing and described below by way of examples of the invention.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic flow diagram depicting a preferred aspect of the present invention for continuous catalytic production of polyoxymethylene dimethyl ethers by chemical conversion of dimethyl ether and formaldehyde in which unreacted dimethyl ether is recovered from the effluent for recycling, and a resulting dimethyl ether-free liquid mixture is heated in a catalytic distillation column with internal stages of contact to convert formaldehyde and methanol present to methylal and higher polyoxymethylene dimethyl ethers. This reaction mixture is contacted with an anion exchange resin to form an essentially acid-free product mixture and fractionated to provide suitable components for blending into diesel fuel. The source of formaldehyde in the integrated process depicted in FIG. 1 is a stream of aqueous formaldehyde in methanol derived from oxidative dehydrogenation of dimethyl ether. In this aspect of invention, recycle gas from the formaldehyde absorber is combined with air, mixed with dimethyl ether, preheated against reactor product, and then fed to the formaldehyde reactor.
GENERAL DESCRIPTION
The improved processes of the present invention employ a heterogeneous, condensation promoting catalyst capable of hydrating dimethyl ether in conversion of dimethyl ether and formaldehyde to form a condensation effluent. In general, after the feedstream is passed over the catalyst it will contain a mixture of organic oxygenates at least one of which is of higher molecular weight than the starting dimethyl ether. For example, effluent mixtures can comprise water, methanol, formaldehyde, dimethyl ether, methylal and other polyoxymethylene dimethyl ethers having a structure represented by the type formula
CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3
in which formula n is a number ranging between 1 and about 15, preferably between 1 and about 10. More preferably the mixture contains a plurality of polyoxymethylene dimethyl ethers having values of n in a range from 2 to about 7. Conditions of reaction include temperatures in a range from about 50° to about 300° C., preferably in a range from about 150° to about 250° C.
Stoichiometry of this condensation may be expressed by the following equations;
CH.sub.3 OCH.sub.3 +n CH.sub.2 OCH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3
2CH.sub.2 OH+m CH.sub.2 OCH.sub.3 O(CH.sub.2 O).sub.m CH.sub.3 +H.sub.2 O
which may be combined as in the following equation when n is equal to m;
CH.sub.3 OCH.sub.3 +2CH.sub.3 OH+2n CH.sub.2 O2CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 +H.sub.2 O
As shown above, the synthesis of methylal and higher polyoxymethylene dimethyl ethers from dimethyl ether, methanol, and formaldehyde is a reversible reaction that yields water as a co-product. Under certain conditions at least a portion of the water may be consumed in a dehydrogenation reaction expressed by the following equations;
CH.sub.3 OCH.sub.3 +CH.sub.3 OH+H.sub.2 O→3CH.sub.2 O+3H.sub.2
and
CH.sub.3 OCH.sub.3 +H.sub.2 O2CH.sub.3 OH
Sources of dimethyl ether useful herein are predominantly dimethyl ether, preferably at least about 80 percent dimethyl ether by weight, and more preferably about 90 percent dimethyl ether by weight. Suitable dimethyl ether sources may contain other oxygen containing compounds such as alkanol and/or water, preferably not more than about 20 percent methanol and/or water by weight, and more preferably not more than about 15 percent methanol and/or water by weight.
The process can be performed at any temperature and pressure at which the reaction proceeds. Preferred temperatures are between about 20° and about 150° C., with between about 90° and about 125° C. being more preferred. The most preferred temperatures are between about 115° and about 125° C.
According to the present invention, the ratio of formaldehyde to dimethyl ether in the feedstreams is any mole ratio which results in the production of the desired oxygenated organic compound. The ratio of formaldehyde to dimethyl ether is preferably between about 10:1 and about 1:10 moles. The ratio of formaldehyde to dimethyl ether is preferable between about 5:1 and about 1:5 moles. More preferably, the ratio of formaldehyde to dimethyl ether is between about 2:1 and about 1:2 moles.
The process can be performed at any temperature and pressure at which the reaction proceeds. Preferred temperatures are between about 20° and about 150° C., with between about 90° and about 125° C. being more preferred. The most preferred temperatures are between about 115° and about 125° C.
The pressure can be atmospheric or super-atmospheric pressure. Preferred pressures are, according to the present invention, between about 1 and about 100 atmospheres, with between about 15 and about 25 atmospheres being most preferred.
The reaction mixture feed gas flow rate, expressed as gas hourly space velocity, can be between about 50 and about 50,000 hr -1 , most preferably, between about 100 and about 2,000 hr -1 . Un-converted dimethyl ether can be recovered from the mixture by methods well known in the art. One particularly desirable method is the use of distillation of the condensed product.
The process of this invention can be performed in either a fixed or fluid bed reactor, using either continuous or batch processing methods. It is preferred to use a fixed bed reactor and a continuous mode of operation.
Broadly, according to the present invention, a catalyst system is provided which comprises at least one molecular sieve, preferably a crystalline metallosilicate exhibiting the MFI crystal structure. Generally the crystalline metallosilicate is combined with active or inactive materials, synthetic or naturally occurring zeolites, as well as inorganic or organic materials which would be useful for binding the crystalline metallosilicate. Other well-known materials include mixtures of silica, silica-alumina, alumina sols, clays, such as bentonite or kaolin, or other binders well known in the art. The crystalline metallosilicate can also be mixed intimately with porous matrix materials, such as silica-magnesia, silica-alumina, silica-thoria, or silica-titania. The crystalline metallosilicate content can vary anywhere from a few up to 100 percent by weight of the total finished product. Typical catalytic compositions contain about 5 percent to about 80 percent by weight of the crystalline metallosilicate.
Generally, the term "molecular sieve" includes a wide variety of positive ion-containing crystalline materials of both natural and synthetic varieties. They are generally characterized as crystalline aluminosilicates, although other crystalline materials are included in the broad definition. The crystalline aluminosilicates are made up of networks of tetrahedra of SiO 4 and AlO 4 moieties in which the silicon and aluminum atoms are cross-linked by the sharing of oxygen atoms. The electrovalence of the aluminum atom is balanced by the use of positive ions such as alkali metal or alkaline earth metal cations.
Zeolitic materials useful herein, both natural and synthetic, have been demonstrated in the past to have catalytic capabilities for many hydrocarbon processes. Zeolitic materials, often referred to as molecular sieves, are ordered porous crystalline aluminosilicates having a definite structure with large and small cavities interconnected by channels. The cavities and channels throughout the crystalline material are generally uniform in size allowing selective separation of hydrocarbons. Consequently, these materials in many instances have come to be classified in the art as molecular sieves and are utilized, in addition to the selective adsorptive processes, for certain catalytic properties. The catalytic properties of these materials are also affected, to some extent, by the size of the molecules which are allowed selectively to penetrate the crystal structure, presumably to be contacted with active catalytic sites within the ordered structure of these materials.
Manufacture of the ZSM materials utilizes a mixed base system in which sodium aluminate and a silicon-containing material are mixed together with sodium hydroxide and an organic base, such as tetrapropylammonium hydroxide and tetrapropylammonium bromide, under specified reaction conditions to form the crystalline aluminosilicate.
A preferred class of useful molecular sieves, according to the present invention, are crystalline borosilicate molecular sieves disclosed in commonly assigned U.S. Pat. No. 4,268,420, U.S. Pat. No. 4,269,813, U.S. Pat. No. 4,292,457, and U.S. Pat. No. 4,292,458 to Marvin R. Klotz, which are incorporated herein by reference.
Suitable for use according to the present invention are, broadly, crystalline borosilicates which comprise a molecular sieve material having the following compositions in terms of mole ratios of oxides:
0.9±0.2 M.sub.2 /.sub.n O:B.sub.2 O.sub.3 :Y SiO.sub.2 :Z H.sub.2 O,
where M is at least one cation having a valence of n, Y is between 4 and about 600, and Z is between 0 and about 160.
Embodiments of such borosilicate provide an X-ray diffraction pattern comprising the following X-ray diffraction lines:
______________________________________ Assigned d (Å) Strength______________________________________ 11.2 ± 0.2 W-VS 10.0 ± 0.2 W-MS 5.97 ± 0.07 W-M 3.82 ± 0.05 VS 3.70 ± 0.05 MS 3.62 ± 0.05 M-MS 2.97 ± 0.02 W-M 1.99 ± 0.02 VW-M______________________________________
wherein the assigned strengths correspond to the following values of relative peak heights:
______________________________________Assigned Strength Relative Peak Height______________________________________VW less than 10W 10-19M 20-39MS 40-70VS greater than 70______________________________________
and "d" represents interplanar spacings, expressed in terms of Angstrom units. A range of assigned strengths comprises all strengths between the limits shown.
Embodiments of these borosilicates are prepared by the method which comprises: (1) preparing a mixture containing an oxide of silicon, an oxide of boron, a hydroxide of an alkali metal or an alkaline earth metal, an alkyl ammonium cation or a precursor of an alkyl ammonium cation, and water; and (2) maintaining said mixture at suitable reaction conditions to effect formation of said borosilicate, said reaction conditions comprising a reaction temperature within the range of about 25° to about 300° C., a pressure of at least the vapor pressure of water at the reaction temperature, and a reaction time that is sufficient to effect crystallization.
After recovering a dimethyl ether-free mixture form the condensation effluent, the mixture is heated in a catalytic distillation column with an acidic catalyst, which is heterogeneous to the feedstream, under conditions of reaction sufficient to convert formaldehyde and methanol present to methylal and higher polyoxymethylene dimethyl ethers. Examples of the solid acidic catalyst for use in the present invention include cation exchange resins, sulfonated fluoroalkylene resin derivatives, and crystalline aluminosilicates.
Cation exchange resins that can be used in the present invention may be carboxylated or sulfonated derivatives, but sulfonated derivatives are preferred because of the high reaction yield that can be attained. Ion exchange resins that can be used may be gel-type cation exchange resins or macroporous (macroreticular) cation-exchange resins, but the latter as exemplified by Amberlite 200C of Organc Co, Ltd. and Lewalit SP112 of Bayer A.G. are preferred because of the high reaction yield that can be attained. Specific examples of useful ion exchange resins include a styrene-divinylbenzene copolymer, an acrylic acid-divinylbenzene copolymer, a methacrylic acid-divinylbenzene copolymer, etc.
A sulfonated tetrafluoroethylene resin derivative (trade name, Naflon H) is preferably used as a sulfonated fluoroalkylene resin derivative.
The most desirable of these solid acidic catalysts are macroreticular cation exchange resins having sulfonate groups.
According to an integrated process of the invention a source of formaldehyde is formed by subjecting dimethyl ether in the vapor phase to oxidative dehydrogenation in the presence of a catalytically effective amount of an oxidative dehydrogenation promoting catalyst comprising silver as an essential catalyst component at elevated temperatures to form a gaseous mixture comprising formaldehyde, methanol, dioxygen, diluent gas, carbon dioxide and water vapor; cooling the gaseous dehydrogenation mixture with an adsorption liquid and adsorbing formaldehyde therein; and separating the resulting liquid source of formaldehyde from a mixture of gases comprising dioxygen, diluent, carbon monoxide, carbon dioxide and water vapor.
According to this aspect of the present invention, the ratio of dioxygen to total dimethyl ether is any mole ratio which results in the production of the desired source of formaldehyde. The ratio of dioxygen to total ether and, if present, alkanol is preferably between about 1:1 and about 1:1000 moles. More preferably, the ratio of dioxygen to dimethyl ether is between about 1:1 and about 1:100 moles. Most preferably, the ratio of dioxygen to dimethyl ether is between about 1:1 and about 1:10 moles.
Operating conditions of reaction usually fall in the following ranges:
Dimethyl ether: 1 mol percent up to 17.4 mol percent
Air: 99 mol percent to 82.6 mol percent
Reaction temperature: 200° to 450° C.
Space velocity: 1,000-20,000 hr -1
Preferable conditions are as follows:
Dimethyl ether: 3 mol percent to 12 mol percent
Reaction temperature: 250° to 400° C.
Space velocity: 1,000-10,000 hr -1
The dioxygen can be added to the reaction mixture as pure molecular oxygen, or diluted with an inert gas such as nitrogen or argon. It is preferred to keep the dioxygen at no more than 10 mole percent of the entire reaction feed so as to avoid the formation of explosive mixtures.
The Karl Fischer process, developed in the early 1900s by Karl Fischer Apparate and Rohrleitungsbau of Germany, is probably the most widely used silver catalyst process.
Several features distinguish this type of process from those catalyzed by metal oxides. Whereas the metal oxide processes achieve an overall yield of about 93 percent, commercial silver catalyzed units are generally believed to achieve an overall yield of about 88 percent. Per-pass methanol conversion is about 80 percent, with 90 percent selectivity to formaldehyde. The silver-catalyzed process operates with an excess of methanol and requires a specialized piece of equipment, such as a packed tower or a methanol boiler equipped with a special air mixer, to generate the methanol-air feed mixture. Since less air is used, however, equipment sizes are smaller and power consumption is less than for the metal oxide process.
The silver-catalyzed reaction is endothermic; but depending on the amount of feed preheat and air added, the exothermic reaction of oxygen with hydrogen sustains the reaction at temperatures in excess of 550° C. Steam can then be generated by cooling the reactor effluent before it is fed to the absorber. However, the steam has a lower pressure (about 30 psig), and the amount produced is insufficient to satisfy process steam requirements. This steam deficit is offset by the fuel value of the substantial amount of hydrogen (more than 18 vol percent) that remains in the absorber off-gas. If the absorber offgas is processed in a thermal oxidizer, a blower for additional combustion air is required, but a substantial amount of 200 psig steam may be produced.
The dioxygen can be added to the reaction mixture as pure molecular oxygen, or diluted with an inert gas such as nitrogen or argon. It is preferred to keep the dioxygen at no more than 10 mole percent of the entire reaction feed so as to avoid the formation of explosive mixtures.
According to the present invention, within the oxidation reaction zone methanol is oxidized with a source of dioxygen in the presence of an oxy-dehydrogenation catalytic composition containing, as an essential ingredient, silver with or without up to about 10 percent of a supplemental inorganic compound based upon the total weight of metal oxide and supplemental inorganic compounds. Suitable oxy-dehydrogenation catalysts have been developed for converting methanol with a source of dioxygen to produce formaldehyde, as described in U.S. Pat. No. 5,401,884, U.S. Pat. No. 5,102,838, U.S. Pat. No. 4,786,743, U.S. Pat. No. 4,521,618, U.S. Pat. No. 4,474,996 and U.S. Pat. No. 4,359,587 which patents are specifically incorporated herein in their entirety by reference.
The starting materials are fed through a silver-containing fixed-bed catalyst installed in a vertical tubular reactor. The catalyst preferably comprises silver crystals having a particle size of from 0.1 to 3 mm, in particular from 0.2 to 2.5 mm. The fixed-bed catalyst can have a multi-layer structure through arrangement of the silver crystals in layers of different particle size.
The starting mixture of methanol vapor, oxygen-containing gas, and, if used, steam and inert gas is preferably passed through the tubular reactor from top to bottom.
Otherwise, the process is carried out in one step by passing the starting mixture through the fixed catalyst bed at from 550° to 750° C., in particular from 600° to 720° C., particularly advantageously at from 660° to 700° C. The process is preferably carried out continuously at from 0.5 to 3 bar, in particular at from 0.8 to 2 bar, preferably at from 1 to 1.5 bar. The residence times in the catalyst zone are from 0.001 to 1 second, preferably from 0.002 to 0.1 second. The reaction gases leaving the catalyst zone are advantageously cooled within a short time, for example to below 350° C. The cooled gas mixture can expediently be fed to an adsorption tower, in which the formaldehyde is washed out of the gas mixture by means of water.
In the present method, dimethyl ether may be used alone, or methanol and dimethyl ether can be used in admixture with each other to produce formaldehyde.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In order to better communicate the present invention, still another preferred aspect of the invention is depicted schematically in FIG. 1. Referring now to FIG. 1, a mixture containing dimethyl ether in substantially liquid form is unloaded, for example from a road tanker (not shown), into dimethyl ether storage vessel 12 which supplies charge pump 14 through conduit 13. Charge pump 14 transfers the liquid dimethyl ether from storage vessel 12 into catalytic reactor 20 through conduit 16 and manifold 22. Aqueous formaldehyde is supplied to manifold 22 through conduit 18, and into catalytic reactor 20 which contains a condensation-promoting catalyst based upon a suitable molecular sieve.
It should be apparent that effluent from the catalytic reactor is a valuable product in itself. A portion of the stream can optionally be diverted from catalytic reactor 20 for delivery to a destination (not shown) where stream may subsequently be separated to recover, for example, dimethyl ether, formaldehyde, methylal and/or other polyoxymethylene dimethyl ethers. The stream can alternatively be utilized as a source of feed stock for chemical manufacturing.
The effluent stream from catalytic reactor 20 is transferred through conduits 23 and 26, by means of pump 24, and into ether recovery column 30, where unreacted dimethyl ether is separated from the effluent stream to form a resulting liquid mixture of condensation products containing any unreacted formaldehyde. A dimethyl ether fraction is taken overhead through conduit 32 and into condenser 34 where a liquid condensate is formed. A suitable portion of the liquid condensate is refluxed into column 30 through conduits 35 and 36 while another portion of the condensate is supplied to manifold 22 through conduits 37 and 39, by means of pump 38, and into catalytic reactor 20.
Conduit 28 supplies pump 40 with liquid from the bottom of column 30. A suitable portion of the liquid stream from the bottom of column 30 is transferred through conduits 41 and 42, by means of pump 40, and into reboiler 43 which is in flow communication with the bottom of the column through conduit 44. A liquid stream from the bottom of column 30 is transferred through conduit 45 into reactive distillation column 50, where simultaneous chemical reaction and multicomponent distillation are carried out coextensively in the same high efficiency, continuous separation apparatus. Optionally, a stream containing methanol from storage vessel 46 may by fed into the reactive distillation column 50. Charge pump 48 transfers methanol in substantially liquid form into the reactive distillation column 50 through conduits 47 and 49.
Solid acidic catalyst is present in the reactive distillation column 50 to allow solutions containing water, methanol, formaldehyde, methylal and one or more other polyoxymethylene dimethyl ethers to be brought into solid-liquid contact counter-currently with the catalyst to form products including methylal and higher molecular weight polyoxymethylene dimethyl ethers. More volatile reaction products are taken overhead from the high efficiency separation apparatus, whereas water and less volatile reaction products are carried down the high efficiency separation apparatus.
The overhead vapor stream from reactive distillation column 50 is transferred through conduit 52 into condenser 54. A suitable portion of condensate from condenser 54 is refluxed into reactive distillation column 50 through conduits 55 and 56. A product stream containing methylal is transferred through conduit 58 to product storage (not shown). Conduit 59 supplies pump 60 with liquid containing higher molecular weight polyoxymethylene dimethyl ethers from the bottom of column 50. A suitable portion of liquid from the bottom of column 50 is transferred, by means of pump 60, through conduits 62 and 63 into reboiler 64 which is in flow communication with the bottom of the column by means of conduit 66. A product stream containing higher molecular weight polyoxymethylene dimethyl ethers is transferred through conduit 68 to product storage (not shown). Preferably, an anion exchange resin is disposed within a section of the distillation column below the stages of contact with the acidic catalyst to form an essentially acid-free mixture.
An aqueous side stream containing low levels of unreacted formaldehyde and/or methanol is discharged from column 50 through conduit 72.
In this aspect of invention, recycle gas from the formaldehyde absorber is combined with air, mixed with dimethyl ether, preheated against reactor product, and then fed to the formaldehyde reactor.
Referring now to the upper portion of FIG. 1, a mixture containing dimethyl ether in substantially liquid form is supplied from dimethyl ether storage vessel 12 to pump 14 through conduit 13. Dimethyl ether is transferred through conduit 15 into feed manifold 92. A recycle stream of wet gas is transferred into feed manifold 92 by means of blower 88. A gaseous stream containing dioxygen and dinitrogen from a source (not shown) is supplied to compressor 94 through conduit 93. Compressed gas is transferred through conduit 95, combined in feed manifold 92 with the recycle stream of wet gas from the formaldehyde adsorber and the dimethyl ether. The resulting mixture is heated against reactor effluent in heat exchanger 80, and transferred into oxidation reactor 90 through conduit 82 and feed manifold 84.
Formaldehyde reactor 90 contains an oxidative dehydrogenation catalyst disposed in thin layer directly above a vertical heat exchanger where effluent from the catalyst layer is promptly cooled. Boiler feed water at about 110° to 130° C. is supplied through conduit 85 to the heat exchanger for generation of low pressure steam in the lower section of the formaldehyde reactor. The steam is transferred through conduit 86, mixed with the preheated mixture of dimethyl ether, wet recycle gas and air stream in feed manifold 84, and transferred into formaldehyde reactor 90. Steam is metered into the preheated methanol-air mixture to control the reactor outlet temperature. The mole ratio of fresh air feed to methanol is between 0.5 and 2.0, preferably about 1.25 and typically the mole ratio of dimethyl ether to steam is about 3. The pressure is only slightly above atmospheric. Since the catalyst layers are less than one inch in thickness, the pressure drop is negligible.
In this embodiment of the invention, metallic silver catalyzes the conversion of dimethyl ether to formaldehyde by a reversible dehydrogenation reaction at temperatures from about 500° to 700° C.:
CH.sub.3 OCH.sub.3 +1/2O.sub.2 →2CH.sub.2 O+H.sub.2
The oxidative dehydrogenation catalyst is generally silver crystals supported on a stainless steel mesh, or a shallow bed of silver crystals, spherical particles, or granules. The reaction is endothermic, and theoretical equilibrium is approximately 50 percent yield at 400° C., 90 percent at 500° C., and 99 percent at 700° C. To conveniently sustain elevated reaction temperatures required to obtain high yields, a portion of the hydrogen formed is oxidized to water. Formation of water is exothermic and provides heat to maintain the endothermic hydrogenation reaction. Heat is also provided by the direct oxidation of methanol:
CH.sub.3 OH+1/2O.sub.2 →CH.sub.2 O+H.sub.2 O
These reactions are rapid and therefore the process is essentially adiabatic. At 650° C., the reaction is substantially complete with contact times of less than 0.01 second. Methanol conversion in the reactor is typically between 65 percent and 80 percent, depending largely on the amount of steam introduced at the methanol vaporization step. Formaldehyde is lost by several side reactions, including those producing co-products including carbon monoxide, carbon dioxide, methane, formic acid, and methyl formate.
To minimize side reactions, it is important to avoid excess oxygen and to operate with exposure time of products and reactants to the catalyst at high temperatures as short as possible. An excess of methanol or methanol and steam is also important, serving to avoid an explosive feed composition. A mixture containing between 6.7 mol percent and 36.5 mol percent methanol in air at 1 atm constitutes a severe explosion hazard.
Gaseous effluent from oxidation reactor 90 is transferred through conduit 96, cooled against the reactor feedstream in exchanger 80 and then passed to an absorption system, where methanol and formaldehyde are absorbed. The effluent gases flow through conduit 98 into spray column 100 where a solution of formaldehyde is formed. Formaldehyde solution from the bottom of spray column 100, at temperatures in a range downward from about 100° C. to about 75° C., is supplied to pump 104 through conduit 103. As previously described, a portion of the aqueous formaldehyde is transferred through conduit 18 and manifold 22 into catalytic reactor 20. Formaldehyde solution from the spray column is generally about 55 percent by weight formaldehyde, about 43 methanol weight percent about 2 weight percent water and less than 350 ppm of formic acid. Another portion of the formaldehyde solution is combined with crude formalin solution, supplied from the bottom adsorption column 110 through conduits 113 and 108, by means of pump 114, and circulated to the top of spray column 100 through conduit 106. It is important to maintain the temperature of the pump-around stream above about 70° C. to prevent paraformaldehyde formation. Optionally, a portion of the cooling required in spray column 100 may be obtained by including a heat exchanger in the flow through conduit 106.
A gaseous overhead stream from spray column 100 is transferred through conduit 102 into adsorption column 110, which contains a high efficiency packing or other means for contacting counter-currently the gaseous stream with aqueous adsorption liquid. A dilute aqueous formaldehyde from the bottom of adsorption column 110 is circulated in a pump-around to the bottom section of the column through conduits 113 and 115, cooler 116, and conduit 117 by means of pump 114.
Further up the column pump-arounds are be cooled to successively lower temperatures. In this embodiment of the invention a liquid side stream is supplied to pump 124 through conduit 125, transferred through manifold 127, cooled in cooler 126, and returned to adsorption column 110 through conduit 128.
In some configurations, the lower pump-around stream is not cooled at all. Caustic solution may be added to the chilled water to improve absorber performance, but it leaves traces of sodium as a contaminant in the product.
A vapor side draw from adsorption column 110 is transferred through conduit 112 and mixed with fresh air as previously described.
The adsorber overhead passes through conduit 118 into condenser 122. An appropriate amount of condensate is formed and refluxed to the top section of the adsorber column through conduit 123. Overhead temperatures in adsorption column 110 are in a range of about 15° to about 55° C., preferably about 30° to about 40° C. Gases are vented from condenser 122 through conduit 120 to disposal, typically, in a thermal oxidation unit (not shown).
The absorber overhead, which contains trace amounts of formaldehyde (about 10-30 ppm), is treated in several ways by catalytic or thermal converter to oxidize hydrocarbons and recuperative heat exchange. Typically, 170 psig to 200 psig steam is generated to improve overall economics of preferred embodiments of the invention.
In view of the features and advantages of the continuous catalytic processes for direct condensation of formaldehyde and dimethyl ether to form a mixture containing one or more polyoxymethylene dimethyl ethers in accordance with this invention, as compared to the known methanol condensation systems previously used, the following examples are given.
EXAMPLES 1 to 3
In Examples 1, 2 and 3 a crystalline borosilicate catalyst exhibiting the MFI crystal structure was used to convert a predominately dimethyl ether feedstream and a liquid feedstream of aqueous formaldehyde in methanol. Effluent of the condensation reactor comprised water, methanol, formaldehyde, dimethyl ether, methylal and higher polyoxymethylene dimethyl ethers having a structure represented by the type formula
CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3
in which formula n is a number from 1 to about 7.
Crystalline borosilicate molecular sieve in the form of an extrudate (1/16 inch) was calcined overnight at 500° C. The calcined extrudate was crushed and sieved to 18-40 mesh. A tubular quartz reactor was charged with 3.27 grams (5 cc) of the sieved particles. The tubular quartz reactor (approx. 10 mm inside diameter) was equipped with a quartz thermowell terminating at about the midpoint of the catalyst bed.
A liquid feed solution was prepared in a pressurized 50 mL autoclave using 11.13 grams of paraformaldehyde (95%), 15.94 grams of methanol, and 1.80 grams of water. Contents of the autoclave were stirred and heated to temperatures of 130° to 140° C. for 1 hour, and then cooled. The resulting solution was fed by a syringe pump into a preheat zone above the catalyst bed. Using mass flow controllers, a gas feed mixture of dimethyl ether and nitrogen was also fed to the top of the reactor.
Liquid products from the reactor were collected in a cool (0° C.) 25 mL flask for subsequent weighing and GC analysis. Gases exiting the collection flask were analyzed by on-line GC using both TCD and FID detectors. Samples of liquid products were collected during sampling intervals of 2 hours over an approximately 16 hour period of operation. Gas analyses were obtained by GC during each sampling interval.
Two samples were collected while temperature of the catalyst bed was controlled to three progressively higher temperatures. Each sample was about 7 grams. Operating conditions and results are summarized in Tables I, II and III.
Net conversion of the methoxy moiety (Net MeO, percent) is an indication of the conversion of groups regardless of origin, i.e., both methanol (MeOH) which has one MeO per mole and dimethyl ether (DME) which has two MeO per mol. Net MeO may be expressed as follows: ##EQU1##
EXAMPLE 4
In this example an acidic catalyst was used to convert a liquid feedstream of formaldehyde in methanol under conditions which allowed gas-liquid contacting of the solid catalyst (trickle bed operation). Effluent of the condensation comprised water, methanol, formaldehyde, dimethyl ether, methylal and higher polyoxymethylene dimethyl ethers.
The acidic catalyst was a proton exchanged sulfonic acid based ion exchange resin. This polymeric material is a Bronstead (protic) acid. A tubular quartz reactor was charged with 5 cc of acidic catalyst particles. The tubular quartz reactor (approx. 10 mm inside diameter) was equipped with a quartz thermowell terminating at about the midpoint of the catalyst bed.
A liquid feed solution was prepared in a pressurized 50 mL autoclave using 7.42 grams of paraformaldehyde (95%) and 15.93 grams of methanol. Contents of the autoclave were stirred and heated to temperatures of 130° to 140° C. for 1 hour, and then cooled. The resulting solution was fed by a syringe pump into a preheat zone above the catalyst bed. Using mass flow controllers, a gas feed mixture of dimethyl ether and nitrogen was also fed to the top of the reactor.
Liquid products from the reactor were collected in a cool (0° C.) 25 mL flask for subsequent weighing and GC analysis. Gases exiting the collection flask were analyzed by on-line GC using both TCD and FID detectors. Operating conditions and results are summarized in Table IV.
EXAMPLE 5
In this example an acidic catalyst was used to convert a mixture of formaldehyde in methanol under conditions which allowed liquid contacting of the solid catalyst. A liquid feed solution was prepared in a pressurized 50 mL autoclave using 7.4 grams of paraformaldehyde (95%) and 15.9 grams of methanol. Contents of the autoclave were stirred and heated to temperatures of 130° to 140° C. for 1 hour, and then cooled. The autoclave was opened and charged with 1.0 gram of catalyst. Contents of the autoclave were heated to reaction temperature for 2 to 3 hours with stirring. After cooling to ambient temperature and settling, the supernatant liquid was sampled for GC analysis and formaldehyde titration analysis. Results are summarized in Table V.
EXAMPLE 6
Products of several condensation runs were composited, and the composite vacuum filtered through a medium glass frit. A 90 gram aliquot of filtrate was shaken with 20 grams of basic ion-exchange resin beads (DOWEX 66) which were then allowed to settle for one hour. The resulting supernatant liquid was then gravity filtered through a medium paper filter. A suitable amount (54 grams) of molecular sieve type 3A, which had been activated by calcination at about 538° C., was mixed into the filtrate, and the mixture allowed to stand overnight at ambient temperatures. Liquid was separated from the sieve by vacuum filtration through a medium glass frit. A 45.97 gram aliquot of this acid-free, dry filtrate was charged to a small distillation apparatus consisting of a 100 mL 3-neck flask, a fractionating column and condenser. The charge was distilled into eight overhead fractions which were collected at temperature cuts according to the following schedule.
______________________________________Schedule of Overhead and Bottom TemperaturesFraction Temperatures, ° C.Number Overhead Bottom______________________________________1 42 to 46 70 to 942 47 to 76 95 to 1093 77 to 94 110 to 1184 95 to 100 119 to 1275 101 to 107 128 to 1366 108 to 112 137 to 1467 113 to 123 147 to 1628 124 to 150 163 to 174______________________________________
White solids (possibly paraformaldehyde) were observed in the column and condenser during cuts 2 through 4, but not thereafter. Composition of the distilled fraction and bottoms are given in Table VI.
EXAMPLE 7
In this Example a silver catalyst in the form of needles was used at several elevated temperatures to provide a source of formaldehyde by oxidative dehydrogenation of dimethyl ether, steam and methanol. A tubular quartz reactor was charged with 3.83 grams (1 cc) of the silver needles. The tubular quartz reactor (approx. 10 mm inside diameter) was equipped with a quartz thermowell terminating at about the midpoint of the catalyst bed. Quartz wool was placed above the catalyst zone to assist in vaporizing liquid feed. The liquid feed solution containing 18.6 percent methanol and 81.4 percent by weight water was fed by a syringe pump into the preheat zone above the catalyst bed. Using mass flow controllers, a gaseous feedstream of 59.93 percent by volume dimethyl ether, 31.59 volume percent nitrogen and 8.48 percent by volume dioxygen was also fed to the top of the reactor. Samples were collected while temperature of the catalyst bed was controlled to temperatures in a range from about 400° to about 650° C. Operating conditions and results are summarized in Table VII.
EXAMPLE 8
In this Example a silver catalyst in the form of needles was used at several elevated temperatures to provide a source of formaldehyde by nonoxidative dehydrogenation of dimethyl ether and steam. The liquid feed of water was fed by a syringe pump into the preheat zone above the catalyst bed. Using mass flow controllers, a gaseous feedstream of 89.1 percent by volume dimethyl ether and 10.9 volume percent nitrogen was also fed to the top of the reactor. Samples were collected while temperature of the catalyst bed was controlled to temperatures in a range from about 400° to about 650° C. Operating conditions and results are summarized in Table VIII
For the purposes of the present invention, "predominantly" is defined as more than about fifty percent. "Substantially" is defined as occurring with sufficient frequency or being present in such proportions as to measurably affect macroscopic properties of an associated compound or system. Where the frequency or proportion for such impact is not clear, substantially is to be regarded as about twenty per cent or more. The term "essentially" is defined as absolutely except that small variations which have no more than a negligible effect on macroscopic qualities and final outcome are permitted, typically up to about one percent.
TABLE I______________________________________Conversion of Feedstreams at about 100° C.Using a Crystalline Borosilicate Catalyst Exhibiting the MFICrystal StructureTemperature, ° C. 100 101Run Time, min 95 155______________________________________Gas Feed, mol percentNitrogen 32.925 32.925DME 67.075 67.075Liquid Feed, weight percentMethanol 55.20 55.20Formaldehyde 38.55 38.55Water 6.25 6.25Feed RatesGas scc/min 34.1 34.1Liquid mL/min 0.00756 0.00756Conversions, mole percentMethanol 67.15 66.96DME 4.36 2.71Net MeO 28.20 27.10Formaldehyde 78.84 78.84Selectivities, percentGases CO 0 0 CO.sub.2 0 0Liquids Methylal 80.548 78.269 HPE 0.750 0.751DME/MeOH 5.38 5.44Carbon Balance 92.57 93.39______________________________________ Where MeOH is methanol, HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
TABLE II______________________________________Conversion of Feedstreams at about 130° C.Using a Crystalline Borosilicate Catalyst Exhibiting the MFICrystal StructureTemperature, ° C. 132 131Run Time, min 245 305______________________________________Gas Feed, mol percentNitrogen 32.925 32.925DME 67.075 67.075Liquid Feed, weight percentMethanol 55.20 55.20Formaldehyde 38.55 38.55Water 6.25 6.25Feed RatesGas scc/min 34.1 34.1Liquid mL/min 0.00756 0.00756Conversions, mole percentMethanol 53.59 53.68DME 5.12 4.75Net MeO 23.52 23.33Formaldehyde 86.71 86.71Selectivities, percentGases CO 0 0 CO.sub.2 0.095 0.086Liquids Methylal 64.480 64.699 HPE 0.323 0.326DME/MeOH 3.48 3.50Carbon Balance 91.63 91.53______________________________________ Where MeOH is methanol, HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
TABLE III______________________________________Conversion of Feedstreams at about 160° C.Using a Crystalline Borosilicate Catalyst Exhibiting the MFICrystal StructureTemperature, ° C. 164 160Run Time, min 345 400______________________________________Gas Feed, mol percentNitrogen 32.925 32.925DME 67.075 67.075Liquid Feed, weight percentMethanol 55.20 55.20Formaldehyde 38.55 38.55Water 6.25 6.25Feed RatesGas scc/min 34.1 34.1Liquid mL/min 0.00756 0.00756Conversions, mole percentMethanol 34.82 35.19DME 7.45 1.12Net MeO 17.84 14.05Formaldehyde 90.59 90.59Selectivities, percentGases CO 0 0 CO.sub.2 0.370 0.317Liquids Methylal 42.970 43.410 HPE 0.094 0.096DME/MeOH 2.37 2.54Carbon Balance 92.40 94.76______________________________________ Where MeOH is methanol, HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
TABLE IV______________________________________Trickle Bed Conversion of Feedstreams Using an Ion ExchangeResin Based Catalyst Exhibiting Bronstead Acid SitesTemperature, ° C. 71______________________________________Feed RatesGas scc/min 10Liquid mL/min 0.0756Conversions, mole percentMethanol 87.04Formaldehyde 92.27Selectivities, percentMethylal 97.78HPE 1.77______________________________________ Where HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1.
TABLE V______________________________________Liquid Phase Conversion Using an Ion Exchange Resin BasedCatalyst Exhibiting Bronstead Acid SitesTemperature, ° C. 67______________________________________Conversions, mole percentMethanol 73.38Formaldehyde 77.91Selectivities, percentMethylal 88.20HPE 6.03______________________________________ Where HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1.
TABLE VI__________________________________________________________________________COMPOSITION OF OVERHEAD FRACTIONS AND BOTTOMSCompound CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 where the value of n is:Fraction Methylal Methanol Hemiacetals Trioxane 2 3 4 5 6 7__________________________________________________________________________Starting 49.95 0.0 0.69 2.42 22.60 12.42 6.40 3.15 1.45 0.611 97.21 0.95 0.05 0.0 0.46 0 0 0 0 02 93.83 2.52 0.38 0.0 2.84 0 0 0 0 03 20.81 12.92 8.85 2.39 54.80 0.17 0 0 0 04 3.24 11.12 6.40 4.49 74.19 0.57 0 0 0 05 0.56 8.47 2.29 5.83 82.07 0.78 0 0 0 06 0.40 3.10 0.16 7.21 88.05 1.08 0 0 0 07 0.43 0.99 0.0 9.38 86.60 2.55 0.05 0 0 08 0.32 0.47 0.0 11.77 82.98 4.37 0.08 0 0 0Bottoms 0.29 0.02 0.0 0.54 1.10 49.49 26.19 13.05 6.34 2.96__________________________________________________________________________
TABLE VII______________________________________Oxidative Dehydrogenation of Dimethyl EtherUsing a Catalyst of Silver NeedlesTemperature, ° C. 397 508Run Time, min 60 100______________________________________Gas Feed, mol percentNitrogen 31.59 31.69DME 59.93 59.93Dioxygen 8.48 8.48Liquid Feed, weight percentMethanol 18.6 18.6Water 81.4 81.4Feed RatesGas scc/min 146 146Liquid mL/min 0.4125 0.4125Conversions, mole percentMethanol 9.21 10.55DME 15.44 16.41Net MeO 14.01 15.08Dioxygen 94.40 93.85Selectivities, percentLight Alkanes 1.37 4.07CO 18.19 20.15CO.sub.2 9.06 7.92Formaldehyde 56.57 59.16Methylal 0 0HPE 0 0DME/Methanol 3.23 3.20______________________________________ Where HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
TABLE VII Continued______________________________________Oxidative Dehydrogenation of Dimethyl EtherUsing a Catalyst of Silver NeedlesTemperature, ° C. 614 660Run Time, min 150 195______________________________________Gas Feed, mol percentNitrogen 31.59 31.69DME 59.93 59.93Dioxygen 8.48 8.48Liquid Feed, weight percentMethanol 18.6 18.6Water 81.4 81.4Feed RatesGas scc/min 146 146Liquid mL/min 0.4125 0.4125Conversions, mole percentMethanol 13.53 15.30DME 17.18 23.94Net MeO 16.34 21.96Dioxygen 94.28 94.53Selectivities, percentLight Alkanes 19.47 28.59CO 25.41 20.15CO.sub.2 5.29 3.39Formaldehyde 45.79 37.70Methylal 0 0HPE 0 0DME/Methanol 3.30 3.10______________________________________ Where HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
TABLE VIII______________________________________Nonoxidative Dehydrogenation of Dimethyl EtherUsing a Catalyst of Silver NeedlesTemperature, ° C. 408 511Run Time, min 115 175______________________________________Gas Feed, mol percentNitrogen 10.9 10.9DME 89.1 89.1Liquid Feed, weight percentWater 100 100Feed RatesGas scc/min 102 102Liquid mL/min 0.07563 0.07563Conversions, mole percentDME 3.63 2.56Net MeO 3.63 2.56Selectivities, percentLight Alkanes 46.21 46.48CO 0 0CO.sub.2 0 0Formaldehyde 53.79 53.52Methylal 0 0HPE 0 0______________________________________ Where HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
TABLE VIII Continued______________________________________Nonoxidative Dehydrogenation of Dimethyl EtherUsing a Catalyst of Silver NeedlesTemperature, ° C. 612 650Run Time, min 290 465______________________________________Gas Feed, mol percentNitrogen 10.9 10.9DME 89.1 89.1Liquid Feed, weight percentWater 100 100Feed RatesGas scc/min 102 102Liquid mL/min 0.07563 0.07563Conversions, mole percentDME 9.38 23.39Net MeO 9.36 23.28Selectivities, percentLight Alkanes 53.06 52.51CO 5.51 14.96CO.sub.2 0.34 0.25Formaldehyde 41.10 32.29Methylal 0 0HPE 0 0______________________________________ Where HPE is higher polyoxymethylene dimethyl ethers which are CH.sub.3 O(CH.sub.2 O).sub.n CH.sub.3 having n greater than 1, MeO is methoxy moiety, and DME is dimethyl ether.
|
A particularly useful process which includes the steps of providing a source of formaldehyde formed by conversion of dimethyl ether in the presence of a catalyst comprising silver as an essential catalyst component; and contacting the source of formaldehyde and a predominately dimethyl ether feedstream with a heterogeneous, condensation promoting catalyst capable of hydrating dimethyl ether under conditions of reaction sufficient to form an effluent comprising water, methanol, formaldehyde, dimethyl ether, and polyoxymethylene dimethyl ethers is disclosed. Unreacted dimethyl ether is recovered from the effluent and recycled to the formation of polyoxymethylene dimethyl ethers. The resulting dimethyl ether-free liquid mixture is heated in the presence of an acidic catalyst to convert at least the methanol and formaldehyde present to polyoxymethylene dimethyl ethers. Advantageously, methylal and higher polyoxymethylene dimethyl ethers are formed and separated in a catalytic distillation column. By including in the column an anion exchange resin, an essentially acid-free product is obtained which can be used directly as a blending component, or fractionated, as by further distillation, to provide more suitable components for blending into diesel fuel.
| 8
|
BACKGROUND OF THE INVENTION
There are currently at least four commercial systems being used to space dye yarns used to fabricate multi-color carpets. These four systems may be divided into two basic classifications known as continuous systems and batch systems.
One of the two continuous systems used in the textile industry is the knit-de-knit space dyeing process which is generally described in U.S. Pat. No. 3,012,303, issued Dec. 12, 1961, to Ralph Whitaker. This process consists of six basic steps. The yarn is first knitted into a fabric after which a stripe or other pattern is printed on the knitted fabric. The color is set by steam color fixation of the knitted fabric which is then scoured to remove gums and excess dyes. After the knitted fabric is dried, the final step includes de-knitting of the knitted fabric to a cone of yarn.
The other of the continuous systems is generally known as warp printing. It also involves six basic steps including preparation of warp sheets (creeling) and thereafter application of a stripe or pattern which is printed on the warp sheet. The color is set by steam color fixation of the warp sheet which is then scoured to remove gums and excess dyes. After the warp sheet is dried, it is split and the yarns rewound onto cones.
Both types of the continuous systems suffer from similar disadvantages in that they require high levels of water consumption and expensive water treatment to remove pollutants. Costs of operation are high due to wasted energy in atmospheric steaming, continuous drying and high labor requirements.
The two batch systems in commercial use are injection dyeing and skein dyeing. Injection dyeing processes have been known for over a half of a century. Still, injection dyeing accounts for only a small portion of the textile yarn being dyed into multi-colors. A typical process for injection dyeing is described in U.S. Pat. No. 1,726,984 to Louis Hasbrouck, dated Sept. 3, 1929. Another injection dyeing process is disclosed in U.S. Pat. No. 3,120,422, dated Feb. 4, 1964. Both of these patents cover dyeing of one cone at a time with the use of hypodermic needles inserted into the cone of yarn to apply the dyes. As hereinbefore noted, injection dyeing processes have not found a great deal of commercial acceptance.
In the other of the batch systems used in the textile industry, the yarn is first unwound from its cones or bobbins to skeins which are loaded into the vat of a dye machine. The skeins are totally submerged in a dye bath and a base color is applied. The skeins are then partially raised out of the dye bath, and may further be rotated depending on the design of the machine and a second color is applied to the portion of the yarn submerged in the dye bath. This step is repeated for each additional color desired, after which the skeins are removed from the dye machine and put into a centrifugal extractor to remove the excess water. The skeins are then dried in an oven drier after which the skein dyed yarn is rewound on cones for further processing.
A typical apparatus for space dyeing of skeins by total submersion and application of a base color and thereafter selective withdrawal or raising of the skeins to apply additional colors to the partially immersed yarn was placed in commercial production in late 1971 by James H. Eakes and is described and illustrated in his application Ser. No. 480,026, filed June 17, 1974, now abandoned. Such apparatus for producing space dyed skeins of yarns is also described and illustrated in O'Mahony et al. U.S. Pat. Nos. 3,926,547 and 3,986,375.
For example, the supercarriers of skeins in such apparatus must be so constructed as to support the greatly increased weight of the yarn following immersion. Generally, a compromise must be accepted by operation at less than full capacity of the apparatus to prevent bending of the cantilever yarn supporting tubes. Additional problems experienced with skein dyeing are: maintaining the liquor ratio constant, high water consumption and high energy requirements. Some of the latter problems are overcome by the vat dyeing process described in my copending application Ser. No. 846,988 filed Oct. 31, 1977 and entitled Method and Apparatus For Randomly Coloring Textile Yarns In A Batch System.
Multi-color or space dyed yarn has experienced a high degree of popularity among carpet manufacturers who continually strive for materials which enable them to meet the demands for continuous changes in styling and an objective of this invention is to provide a much more economical, practical and convenient method and apparatus for the space dyeing of yarns.
More particularly, it is an objective of the invention to provide a continuous process for space dyeing yarns which economizes on the consumption of water and energy while utilizing a comparatively simple and inexpensive apparatus.
Another objective is to provide a continuous process for space dyeing yarns which avoids the drawbacks of the prior art knit-de-knit, warp printing processes and vat dyeing processes.
Other objectives and advantages of the invention will become apparent during the course of the following description.
SUMMARY OF THE INVENTION
A multiplicity of yarns are continuously fed in spaced relationship from yarn supply bobbins to a skein winding mechanism. During their movements, the yarns are engaged at two separated dyeing stations by reciprocating guide devices which cause the yarns to deviate or oscillate back and forth laterally at the two stations from their primary longitudinal paths of movement. At the two dyeing stations and while the yarns are oscillated back and forth, multiple dye streams from overhead banks of dye feeder tubes are directed onto the moving yarns. Each dye tube is positioned such that its dye stream or streams, as the case may be, intersects the primary path of movement of and associated strand of yarn. As a result of this, the continuous dye streams impinge on the yarns. at longitudinally spaced portions therealong, leaving intervening portions of the yarns undyed. The spacing of the dyed and undyed regions on the yarns can be varied by changing the transport speed of the yarns, the amplitude and speed of the reciprocating yarn guide means, and by selectively operating varying numbers of dye feeder tubes in one or both banks of tubes.
A complete system embodying the invention comprises continuously transporting the spaced yarns from their supply bobbins to the skein winding mechanism while space dyeing the yarns in the above-described manner, followed by steam fixing of the dye in the space dyed skeins, and then overdyeing the skeins in a vat type batch dyer, followed by additional conventional fixing, washing and liquid expelling steps.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a yarn space dyeing apparatus employed in the practice of the method.
FIG. 2 is an enlarged vertical section taken on line 2--2 of FIG. 1.
FIGS. 3, 4 and 5 are partly schematic plan views showing stationary and reciprocating yarn guides which cause the yarns to deviate laterally from their main paths of travel at the dyeing stations.
FIG. 6 is an enlarged schematic view showing the sinusoidal path of movement of one point on each yarn at each dyeing station.
FIG. 7 is an enlarged fragmentary elevational view of a section of yarn after space dyeing in accordance with the invention.
FIG. 8 is a flow diagram for the space dyeing apparatus.
FIG. 9 is a block diagram of a complete yarn dyeing system embodying the invention.
FIG. 10 is a fragmentary side elevation of a reciprocating yarn guide and support means.
FIG. 11 is a fragmentary side elevation and cross sectional view of the end of a dye tube terminating at an adapter for splitting an individual dye stream into a plurality of streams.
DETAILED DESCRIPTION
Referring to the drawings in detail wherein like numerals designate like parts, a space dyeing apparatus employed in the practice of a yarn dyeing method is shown in FIG. 1 and comprises a support frame 20 on which are mounted first and second fixed vertical guide plates 21 and 22 in spaced parallel relation, each plate having a multiplicity of equidistantly spaced yarn guide apertures 23 formed therethrough.
Slightly downstream from the fixed guide plate 21, in relation to the direction of movement of the yarns, and slightly upstream from the guide plate 22 are first and second yarn guides 24 and 25 or channels which extend transversely of the yarns and parallel to the fixed guide plates 21 and 22. Each yarn guide is formed by a pair of spaced opposed parallel angle bars 26', see FIG. 2, rigidly interconnected near their ends by cross brackets 26a or by other suitable means. Continuous slots 27', for a purpose to be described, are formed between the angle bars 26' of each guide 24 and 25. The vertical webs of the angle bars 26' have top opening slots 26 formed therein in the same spaced relationship as the apertures 23 of the fixed plates 21 and 22. The slots 26 receive and guide individual yarns being transported through the apparatus at right angles to the guides 24 and 25, as will be further described.
As shown in FIG. 1, multiple yarns Y, preferably corresponding in number to the guide apertures 23 and slots 26, are drawn from bobbins or cones 27 of a conventional creel 28, FIG. 9, by the operation of a conventional skein winding mechanism 29 at the downstream end of the space dyeing apparatus. The individual yarns Y are threaded through the fixed guide apertures 23 of both guide plates 21 and 22 and are engaged within the slots 26 of the guides 24 and 25, as best shown in FIG. 2.
Means are provided to simultaneously reciprocate the guides 24 and 25 at desired rates and amplitudes of reciprocation. This means comprises a suitable drive motor 30 on the frame 20 which powers a take-off belt 31, connected with and driving a countershaft 32, which in turn drives vertical belts 33 and 34. Belts 33 and 34 are connected with the drive pulleys 35 mounted on short horizontal drive shafts held in bearings 36 on the Frame 20. The two drive shafts carry eccentrics 37, connected at 38 to oscillating drive links 39, which in turn are connected at 40 to pairs of reciprocating slides 41 at each end of the apparatus on which the guides 24 and 25 are fixedly mounted. The slides 41 for the reciprocating guides are in turn slidably mounted on short cantilever support members 41' at each side of the frame 20, the members 41' having suitable bearing pads 41a, FIG. 2, fixed to their top faces to reduce friction in the two reciprocating guides 24 and 25. The slides 41 of the reciprocating guides terminate slightly inwardly of the opposite ends of the paired angle bars 26' and lap the bottoms of the same for a sufficient distance only to support the angle bars firmly, as shown in FIG. 10. This arrangement allows the longitudinal slots 27' of the two reciprocating guides to be open and unobstructed throughout their lengths for the free passage of multiple dye streams downwardly therethrough, as will be further described.
The strokes of the two reciprocating yarn guides 24 and 25 composed of the elements 26' and 41 may be regulated in any conventional way, as by changing the location of the eccentric connections 38 of drive links 39. Also, the speeds of reciprocation of the two guides may be varied conventionally to render the process more versatile.
In the space dyeing apparatus, the locations of the two reciprocating yarn guides 24 and 25 and their slots 27' establish first and second dyeing stations A and B in the apparatus where multiple streams of liquid dye are delivered onto the moving yarns Y. To accomplish this, first and second dye headers 42 and 43 are fixedly mounted on an elevated extension of the apparatus frame 20 at the center of the apparatus. The two headers 42 and 43 are parallel to the yarn guiding means and substantially co-extensive lengthwise therewith, as shown. Dye stream feeder tubes 45 in two banks lead from the headers 42 and 43 and are directed downwardly in parallel spaced relationship, the feeder tubes corresponding in number and spacing to the yarn guide apertures 23 and slots 26. The lower dye discharge ends of the feeder tubes 45 terminate at the same elevation slightly above and in alignment with the slots 27' of reciprocating guides 24 and 25 at the two dyeing stations A and B of the apparatus. The lower or delivery ends of the dye streams exiting from the feeder tubes are preferably arranged to feed into individual adapters 46 associated with each tube which serve to break up the individual dye streams flowing through the tubes into one or more dye streams. To this end, as shown in FIG. 11, each adapter 46 includes one or more outlet apertures 46' in its lowermost wall and an upwardly extending inlet nipple 45' over which the discharge end of the associated tube 45 is anchored. Advantageously, tubes 45 may be of soft plastic material of a diameter equal to or slightly less than the outside diameter of nipple 45'. This enables a tube 45 to be stretched in a tight sealing engagement with the associated nipple 45'. If desired, suitable hose clamps may be used to ensure a tight seal or tube 45 may be fabricated of metallic material and provided with internal threads or a threaded fitting for threaded engagement with mating threads provided on nipple 45. Adapters 46 are anchored to fixed frame bars 47 slightly above the guides 24 and 24, FIG. 2. The discharge ends of the adapters 46 are centered relative to the two reciprocating guides 24 and 25 and their slots so that the dye streams delivered downwardly from the tubes in the two banks are at right angles to the yarns Y, which yarns travel in a plane slightly below the discharge ends of the adapters.
Referring to FIG. 8, the dye headers 42 and 43 are continuously supplied with dye through a conduit 48-48', fed by a pump 49 which receives dye from a dye mixer 50. An overflow conduit 51 connected in conduit 48 downstream from the pump 49 returns excess dye to the mixer 50. Powdered dye is dissolved in tank 52 and is delivered by pump 53 and line 54 into mixer 50--and a recirculating line 55 connected in line 54 allows the dissolved powdered dye to be recirculated to insure proper dye solution. A pair of excess dye recovery troughs 56 positioned below the slots 27' of reciprocating guides 24 and 25 at the two dyeing stations A and B collect and return excess dye from the tubes 45 through return conduits 57 to a holding tank 58, from which another pump 59 moves the dye through a return line 60 back to the dye mixer 50.
The operation of the apparatus in the practice of the yarn space dyeing method is best understood by reference to FIGS. 3 through 6. FIGS. 3 to 5 show the constantly changing relationship of the moving web of yarns Y to the fixed dye stream delivery tubes 45 caused by reciprocation of the guides 24 and 25 across the primary paths of movements of the yarns at dyeing stations A and B. FIG. 3 shows the reciprocating slotted yarn guide 24 at the median position where the yarns Y are directly under the discharge ends of tubes 45 and therefore intersecting the associated dye streams traveling downwardly from the tubes.
FIG. 4 shows the reciprocating guide 24 shifting the yarns laterally to one side of the fixed tubes 45 as at Y a , with the yarns out of alignment with the tubes and thus escaping the action of the dye stream, as the yarns continue to advance through the apparatus. At this time, the dye streams simply pass through the slots 27' and into the recovery troughs 56 at the two dyeing stations without effecting any dyeing of yarns.
FIG. 5 shows a condition similar to FIG. 4, except that the yarns Y are shifted by the guide 24 laterally beyond the other sides of the fixed tubes 45 so that the yarns are again escaping the dye streams while continuing to travel through the apparatus toward the skein builder 29.
For purposes of illustration and simplification, the dye streams are represented as exiting from the dye tubes 45. In actual practice, the dye stream exits from an adapter 46 (FIG. 11). If adapter 46 contains a single opening, the resultant dye stream is directly over the yarn in the median position. Where adapter 46 contains two or more openings, the resultant dye streams may be displaced from the medium position; however, the breadth of the multiple dye streams from an adapter is such that at maximum lateral movement of the yarn in either direction, the yarn is beyond the fall of the associated dye streams as shown in FIGS. 4 and 5.
In shifting from their positions in FIG. 4 to those shown in FIG. 5, it will be understood that the yarns Y in the web of yarns again pass through the median position shown in FIG. 3 and in doing so, again intersect the dye streams which are constantly delivered from the tubes 45. Thus, the yarns are again dyed at localized points. This continuous back and forth deviation or lateral shifting of the yarns on opposite sides of their primary paths of travel caused by the reciprocating guides 24 and 25 at the two dyeing stations is rapid and repetitive, and as a result, all of the yarns Y are randomly dyed or space dyed at a multiplicity of localized regions shown at 61 in FIG. 7 with the intervening regions 62 of the yarns remaining undyed, as these are the regions which escaped the dye streams from the tubes 45 with the yarns in the shifted positions of FIGS. 4 and 5.
FIG. 6 illustrates that during the simultaneous longitudinal and transverse movements of the yarns at dyeing stations A and B a given point on each yarn Y follows a sinusoidal path S while traveling beneath the tubes 45. Broken lines 63 in FIG. 6 denote the limits of the back and forth stroke of each reciprocating guide 24 and 25. Depending on the length of this stroke and the transport speed of the yarns, the yarns may deviate laterally back and forth on the sinusoidal paths several times at each dyeing station as graphically illustrated in FIG. 6.
As previously noted, the process is versatile and the space dyeing of yarns may be widely varied in the process to change the spacing of the colored and uncolored zones 61 and 62, FIG. 7. For example, the transport speed of the yarns through the apparatus can be adjusted, a typical linear speed being about 400 yards per minute as the yarns travel between the supply cones 27 and skein builder 29. The reciprocation strokes of the guides 24 and 25 may be varied, a typical stroke being one inch and a typical rate of reciprocation being about 180 strokes per minute. Also, the apparatus may operate with only one dye header 42 active and with the other header shut off by closing the valve 64 shown in FIG. 8 which is connected in the conduit 48'. Similarly, during the operation of one or both of the headers 42 and 43, selected numbers of dye feeder tubes 45 in one or both banks may be operated while other selected tubes are shut off by closing valves 65 provided therein. Thus, a variety of space dyeing patterns can be obtained in the process.
If the dye pump 49 is an expensive metered pump, the two headers 42 and 43 can be maintained full of dye at all times and equal volumes of dye will be discharged through all of the tubes 45. Alternatively, as illustrated, where a less expensive pump 49 is employed in the apparatus, a pair of upstanding sight tubes 42' and 43' may be provided on the headers 42 and 43 near their centers to form small overflow reservoirs and to also serve as sight tubes or gages. As long as the tubes 42' and 43' contain liquid dye above the level of the headers 42 and 43, the operator of the process is assured that the headers are full and equal streams of dye are being delivered from all of the tubes 45 in the two banks of tubes at dyeing stations A and B. The arrangement dispenses with the necessity for a more expensive metered pump in the system.
FIG. 9 is a block diagram of a complete yarn dyeing system including the space dyeing apparatus and process herein as a part thereof. The described space dyeing process in FIG. 9 is illustrated by the block numbered 2. Ahead of this block, the creel for bobbins or cones 27 is shown in block 1 at 28 while the skein builder 29 is shown in block 3. The usual batch steamer to fix the dye in the space dyed skeins is indicated at block 4, and at block 5 of the diagram the space dyed skeins are over-dyed in any desired shade in a batch dyeing vat, followed by other conventional treatment dye fixing and washing steps, not shown. Suitable apparatus for vat dyeing and treatment may take the form shown in U.S. Pat. No. 1,911,305, the aforementioned abandoned application Ser. No. 480,026 of James Eakes, U.S. Pat. No. 3,926,547 or my aforementioned application Ser. No. 846,988 or any conventional batch skein dyeing apparatus.
The continuous space dyeing process forming the main subject matter of the invention is fast and economical and free of the drawbacks present in the prior art which were discussed in the introduction to the application. Notably, the invention economizes the use of water and energy compared to the prior art.
It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be restored to, without departing from the spirit of the invention or scope of the subjoined claims.
|
Multiple strands of undyed yarn are fed continuously from supply spools or bobbins supported on a creel to a skein winding apparatus. The strands each pass along a substantially horizontal path through one or more spaced dyeing stations where they are engaged by an oscillating frame and caused to oscillate laterally back and forth from said paths while streams of dye individual to the yarns are continuously directed onto the yarns from a series of overhead tubes at the dyeing stations. The strands thus periodically interrupt the dye stream of the associated tubes and receive dye at a multiplicity of spaced portions along their lengths with intervening portions of the yarns remaining uncolored. The space dyeing can be varied by changing the speed of movement of the yarns, by varying the amplitude and speed of movement of yarn guide means which produces the lateral oscillation of the yarns and by selectively operating varying numbers of dye stream feeders at one or both dyeing stations. Upon completion of the space dyeing operation, the individual skeins of yarn can be batch dyed in an overcolor.
| 3
|
STATE OF THE ART
[0001] Orlistat is an active principle belonging to the therapeutic anti-obesity agents group of formula
[0000]
[0002] Orlistat is administered in conjunction with low calorie diets for treating patients affected by obesity having a body mass index (BMI) greater than or equal to 30 kg/m 2 , or overweight patients with a BMI ≧28 kg/m 2 with associated risk factors. Orlistat is a substance which, from the technological viewpoint, has some stability problems; in this respect the active principle Orlistat is low melting (around 44° C.) and undergoes rapid hydrolysis in the presence of water or moisture. Stability studies of the raw material, under ICH conditions (25° C., 65% RH) show a 15% degradation of the active principle after 7 days' storage.
[0003] Furthermore, degradation is directly proportional to temperature; at a temperature of 40° C. and RH of 75% degradation is greater than 40%.
[0004] In order to overcome said degradation, formulations in soft capsules have been produced as described in U.S. Pat. No. 4,598,089 filed on 18 Jun. 1984 in which the active principle was dissolved in the triglyceride mixture NEOBEE M-5, then distributed into soft gelatin capsules.
[0005] Subsequently, in U.S. Pat. No. 6,004,996 filed on 6 Jan. 1998, a formulation in granules/pellets was described containing as excipient a stabilizer able to control the degree of humidity and not to degrade the Orlistat. This formulation contains excipients such as: diluents, surfactants and disintegrants.
[0006] In U.S. Pat. No. 6,358,522 filed on 10 Aug. 1999, formulations in the form of a powder and chewable tablets containing Orlistat combined with a thickening agent and an emulsifier are described.
SUMMARY OF THE INVENTION
[0007] The present invention relates to a pharmaceutical formulation based on Orlistat solubilized in mixtures of saturated hydrocarbons obtained from petroleum. These substances due to their lipophilicity do not contain water, the Orlistat being easily solubilized therein. An ionic, non-ionic or amphoteric surfactant is then added to the Orlistat solution obtained.
[0008] Surprisingly, the formulation thus attained is found to be stable with an excellent in-vitro dissolution profile.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The invention relates to highly stable pharmaceutical preparations for treating obesity which contain Orlistat as the active principle.
[0010] The Orlistat is solubilized in mixtures of pharmaceutically acceptable saturated hydrocarbons obtained from petroleum, with an active principle:solvent ratio of between 1:0.5 and 1:10, preferably between 1:1 and 1:2.
[0011] Suitable mineral oils are paraffin oil, light paraffin oil, Liquid Paraffin and Paraffin Light Liquid (as described in the European Pharmacopeia). The Paraffin Hard product described in the European Pharmacopeia while having a waxy consistency has also shown an excellent capacity for solubilizing Orlistat, either alone or mixed with other paraffinic oils.
[0012] The mineral oil Paraffin Liquid has a relative density of 0.82-0.89.
[0013] The mineral oil Paraffin Light Liquid has a relative density of 0.810-0.875.
[0014] The product Paraffin Hard has a melting point of 50-61° C.
[0015] The Orlistat solution in saturated hydrocarbon mixtures obtained from petroleum is further supplemented with one or more ionic, non-ionic or amphoteric surfactants in a ratio of active principle:surfactant of between 1:0.001 and 1:1, preferably between 1:0.01 and 1:0.05.
[0016] Examples of suitable surfactants are sodium lauryl sulfate, Tween 20, 60, 80, alkylamidobetaine and phospholipids, either taken singly or mixed together. Other surfactants useful for implementing the present invention are: Macrogolglycerol ricinoleate, Macrogolglycerol hydroxystearate, Polysorbate 20, Polysorbate 21, Polysorbate 40, Polysorbate 61, Polysorbate 65, Polysorbate 81, Polysorbate 85, lauryl alcohol polyethanoleate, soya, maize or egg lecithins, lecithins purified to the extent of 60, 70, 80, 90 and 95% phosphatidylcholine and 80, 90 and 100% hydrogenated phosphatidylcholine.
[0017] The solution of active principle in the paraffinic oil containing the surfactant can be inserted into soft capsules or hard gelatin capsules.
[0018] Some purely illustrative examples of the invention are given below with relative solubility and stability data of the prepared products.
EXAMPLES
Example 1
Soft Capsules
[0019]
[0000]
Active principle:
Orlistat
120,000
mg
Excipients for the fill:
light paraffin oil
280,140
mg
Sodium lauryl sulfate
2,805
mg
Excipients for the shell:
Gelatin
132,800
mg
Glycerol
77,200
mg
Titanium Dioxide
6,200
mg
Capsule characteristics: oval D
Preparation Method
Preparation of the Fill
[0020] 0.350 kg of light paraffin oil were introduced into a stainless steel container and, stirring gently with rotating paddles, 0.0035 kg of sodium lauryl sulfate were added. Stirring was continued until complete dissolution of the surfactant.
[0021] The Orlistat (0.15 kg) was added to the solution thus obtained, gently stirring until complete dissolution.
[0022] The solution thus obtained was deaerated and maintained under vacuum.
Preparation of the Shell
[0023] 9.41 kg of purified water was introduced into a container equipped with heated jacket and stirrer, the temperature being controlled at 80° C.
[0024] While stirring vigorously the glycerol (6.76 kg) and the gelatin (12.65 kg) were added, to the warmed water until complete dissolution.
[0025] The gelatin/glycerol/water solution thus obtained was maintained under vacuum, controlling the temperature at 80° C.
[0026] The colouring agent was then added to this solution, prepared by dispersing titanium dioxide (0.59 kg) in glycerol (0.59 kg) with a turboemulsifier.
[0027] The titanium dioxide in glycerol dispersion was added to the gelatin/glycerol/water solution to disperse the colouring while maintaining the temperature always at 80° C.
Encapsulation
[0028] By means of an encapsulating machine, the coating mass was placed in the two appropriate hoppers and passed through laminators at 60° C. so as to form the coating.
[0029] The sheets were moulded through suitable rollers and 403.0 mg of the Orlistat solution were inserted between the two gelatin sheets with a suitable dosing needle.
Drying
[0030] The thus prepared capsules were placed in rotating drying tubes and, after pre-drying, were positioned on suitable racks in temperature controlled cupboards at 21-22° C. and 20% RH for 1-2 days.
Solubility Tests
[0031] The dissolution profile was characterized in-vitro in accordance with the following methodology:
Method: USP Apparatus: Paddle II Medium: phosphate buffer pH 6.9 Volume: 900 ml Rotation speed: 100 r.p.m Temperature: 37° C.
Solubility results (%)
[0000]
Sample
After 10′
After 20′
After 30′
After 45′
No. 1
12.7
55.6
75.9
85.8
No. 2
15.2
50.7
79.9
88.7
No. 3
11.0
60.4
80.1
86.7
No. 4
16.4
58.8
77.9
86.4
No. 5
14.4
61.1
76.1
89.3
No. 6
14.9
60.2
80.7
95.1
[0038] The Orlistat-based preparations in soft capsules were subjected to ICH stability studies at conditions of 25° C. 60% RH, 30° C. 70% RH and 40° C. 75% RH and demonstrated excellent active principle stability.
[0039] The active principle titres were determined by analysis with HPLC Diode Array MD1510, using 70:30 methanol:water as the mobile phase, with Lichrosphere RP8 column 125×4 mm, 5 mcm (Merck), at a wavelength of 210 nm.
Stability Results:
[0040]
[0000]
isothermal 25° C. 60% RH
T zero
1 month
3 months
6 months
9 months
12 months
orlistat HPLC
100.00%
100.01%
100.00%
100.20%
100.01%
100.2%
titre
isothermal 30° C. 70% RH
T zero
1 month
3 months
6 months
9 months
12 months
orlistat HPLC
100.00%
100.01%
100.00%
100.20%
100.01%
100.2%
titre
isothermal 40° C. 75% RH
T zero
1 month
3 months
6 months
orlistat HPLC
100.00%
99.90%
99.80%
99.90%
titre
Example 2
Soft Capsules
[0041]
[0000]
Active principle:
Orlistat
120,000 mg
Excipients for the fill:
paraffin oil
263,000 mg
Tween 80
20,000 mg
Excipients for the capsule:
Gelatin
132,800 mg
Glycerol
77,200 mg
Iron oxide
6,200 mg
Capsule characteristics: 10 oval D
Preparation Method
Preparation of the Fill
[0042] The paraffin oil (0.263 kg) was weighed and inserted into a stainless steel container and, stirring gently with rotating paddles, Tween 80 (0.020 kg) was added and dissolved. Stirring was continued until complete dissolution of the surfactant.
[0043] The Orlistat (0.12 kg) was added to the solution thus obtained and dissolved while gently stirring.
[0044] The solution thus obtained was deaerated and maintained under vacuum.
[0000] Preparation of the Capsule 5 9.41 kg of purified water were introduced into a container equipped with heated jacket and stirrer, the temperature being controlled at 80° C.
[0045] While stirring vigorously the glycerol (6.76 kg) then the gelatin (12.65 kg) were added to the thus heated water and dissolved.
[0046] The gelatin/glycerol/water solution thus obtained was maintained under vacuum and temperature controlled at 80° C.
[0047] The colouring agent, prepared by dispersing the iron oxide (0.59 kg) in glycerol (0.59 kg) with a turboemulsifier, was added to this solution.
[0048] The iron oxide in glycerol dispersion was added to the gelatin/glycerol/water solution to disperse the colouring while maintaining the temperature at 80° C.
Encapsulation
[0049] By means of an encapsulating machine, the coating mass was placed in the two appropriate hoppers and passed through laminators at 60° C. so as to form the coating.
[0050] The sheets were passed through suitable rollers to allow moulding and 403.0 mg of the Orlistat solution were inserted between the two gelatin sheets with a suitable dosing needle.
Drying
[0051] The already prepared capsules were placed in rotating drying tubes and, after pre-drying, were placed onto suitable racks in temperature controlled cupboards at 21-22° C. and 20% RH for 1-2 days.
Example 3
Hard Gelatin Capsules
[0052]
[0000]
Active principle:
Orlistat
120,000 mg
Excipients:
Paraffin Liquid
100,000 mg
Paraffin Hard
60,000 mg
Phosphatidylcholine (80)
20,000 mg
Capsule: size 00 white opaque, average weight 118 mg ± 7.0 mg.
Preparation Method
Preparation
[0053] The Paraffin Liquid (10.000 kg) and Paraffin Hard (6.000 kg) were weighed, placed in a stainless steel container and melted at a temperature of 70° C., stirring gently with rotating paddles; the phosphatidylcholine (2.000 kg) was then added and melted. Stirring was maintained until this latter dissolved completely, controlling the temperature at 30° C.
[0054] The Orlistat (12.00 kg) was added to the solution thus obtained and dissolved while gently stirring.
Encapsulation
[0055] Using a hard capsule filling machine equipped to dispense liquids, the liquid was dispensed into hard gelatin capsules, size 00, to a weight of 300 mg/cps of fill.
|
Pharmaceutical compositions are for administered orally for treating patients affected by obesity. The compositions include orlistat (tetrahydrolipstatin) solubilized in pharmaceutically acceptable saturated hydrocarbons obtained from petroleum and one or more surfactants.
| 0
|
FIELD OF THE INVENTION
This invention relates to weighted gloves, and more particularly to a glove worn on the free hand of a bowler with weights located both above and below the metacarpal region of the hand.
DESCRIPTION OF THE PRIOR ART
Participants in the sport of bowling are well aware of the imbalance created by the one-sided pull of the bowling ball during its delivery. The arm motion involved in delivering a bowling ball tends to pull the ball-side shoulder downward, and if this shoulder position is not corrected, it interferes with the bowler's accuracy in hitting the target. It is thus well recognized in bowling that accurate delivery of the ball on target is fostered by maintaining the shoulders square at the foul line. It is also known that bowling scores are enhanced by not rushing the foul line, by providing a consistent ball release and by providing firmer slide-foot position at the foul line.
It has heretofore been suggested that the provision of a weight on the bowler's free hand operates to counterbalance the one-sided pull of the bowling ball. Devices embodying this technique are disclosed in U.S. Pat. No. 3,203,006, issued to L. H. Shirey and U.S. Pat. No. 3,149,839, issued to F. S. Materia.
However, some prior glove devices have not been found to be fully effective in forcing a bowler to use proper bowling movements, and have sometimes been somewhat uncomfortable and impractical to wear while bowling. A need has thus arisen for a weight glove which is operable to teach proper bowling techniques. The weight glove must be comfortable to wear, while at the same time placing a correct sized weight as far from the body as possible to serve as a counterbalancing force. For the beginning bowler, such a weight glove would create good bowling techniques much easier and quicker, while for the experienced bowler, the weight glove could be worn to replace undesirable and deeply engrained bowling habits with the proper delivery from, thereby leading to higher scoring and more enjoyment of the game.
SUMMARY OF THE INVENTION
The present invention provides a weight glove which eliminates and reduces the problems heretofore associated with prior art devices. The present weight glove is particularly weighted and configured to be worn by a bowler on his free hand to foster correct bowling techniques by counterbalancing the one-sided shoulder pull of the bowling ball.
In accordance with the present invention, a glove has a plurality of attached weight receiving pockets which are disposed both above and below the metacarpal area of the hand. A first weight is positioned within the weight receiving pocket above the metacarpal region of the hand, while a second weight is positioned below the metacarpal region of the hand. The glove includes a rectangularly shaped piece of material with a slot formed therein for receiving the wearer's thumb, and including structure for removably fastening the glove around the hand. The first and second weights are anatomically shaped to conform to the contour of the wearer's hand.
In accordance with another aspect of the present invention, a glove has two weight receiving pockets attached to it, the first of the pockets positioned over the metacarpal area of the hand and the second of the pockets positioned under this area. A first weight is positioned within the first weight receiving pocket and a second weight is positioned within the second weight receiving pocket. The first weight is anatomically shaped to conform to the contour of the back of the wearer's hand, while the second weight is anatomically shaped to fit the contour of the palm area of the hand. The first weight is a solid weight having a concave surface on one side to conform to the contour of the back of the wearer's hand, with a convex surface formed on the weight's opposite side. The first weight has a pad adhesively affixed to the concave surface pressing against the back of the wearer's hand, while the convex surface is regularly indented to give a waffle like appearance. The second anatomically shaped weight is kidney shaped, with the concave surface of the weight opposing the base of the thumb. The glove itself is an essentially rectangular flexible sheet having a slot formed in it for inserting the thumb, with structure for fastening the glove to the wearer's hand.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further objects and advantages thereof, reference is now made to the following description taken in conjunction with the following drawings:
FIG. 1 is a perspective view of a bowler wearing the preferred embodiment of the present invention on his free hand while delivering a bowling ball at the foul line;
FIG. 2 illustrates a top view of the lefthand version of the preferred embodiment of the invention;
FIG. 3 is a bottom view of the lefthand version of the present invention;
FIG. 4 is a front side view of the lefthand version of the present invention taken along line 4--4 in FIG. 2;
FIG. 5 is a perspective view of the first weight in the preferred embodiment of the invention;
FIG. 6 is a perspective view of the second weight of the preferred embodiment of the invention; and
FIG. 7 is a perspective view, partially broken away, of the lefthand version of the preferred embodiment of the invention as it is worn by a bowler.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates the preferred embodiment of the present weight glove, generally indicated by reference numeral 10, worn on the left hand by a right-handed bowler. The weight glove 10 produces a counterbalancing force on the free hand of the bowler to correct the one-sided pull on the right side caused by the motion of delivering the bowling ball, and to improve other aspects of the bowling delivery.
Referring to FIGS. 2, 3 and 4, the weight glove 10 includes a substantially rectangular sheet of material 12 having a generally elliptical slot 14 formed therethrough for receiving the thumb of the left hand, the free hand of a right-handed bowler. The sheet 12 may be constructed of any suitable material well known to those in the art of making gloves. Porous materials, such as porous types of Naugahyde (trademark), are particularly suited for use as sheet 12 due to the comfort they afford the wearer by allowing air to circulate through the material. The sheet 12 includes a set of Velcro-type fastening pads 16 at the top of the glove, and a second set of Velcro-type fastening pads 18 attached at the bottom of the glove. Velcro-type fastening pads are useful for securely and quickly fastening the wrap around sheet 12 together when it is placed on the hand. The Velcro-type fastener includes a pad with a plurality of exposed fibers suitable for holding the fiber hooks of an opposed pad when pressed together. It will be understood that other suitable fastening structure, such as snaps and buckles, for example, could also be used to secure sheet 12 in place around the wearer's hand.
The weight glove 10 is shown constructed from a sheet of material 12 that is wrapped around a hand of the wearer, but it should be understood that a glove could be constructed utilizing the present inventive concepts in the well known manner covering the hand and having a separate sheath for each finger. The preferred embodiment of the invention shown in FIGS. 2, 3 and 4 has the advantages of being economical to manufacture, comfortable to wear, and quickly put on or taken off by the wearer.
A first weight receiving pocket 20 is affixed to the top side of the sheet 12 so that the weight pocket 20 is positioned over the metacarpal region of the hand when the glove 10 is worn. A second weight receiving pocket 22 is affixed to the opposite side of the sheet 12, so that the weight receiving pocket 22 is positioned below the metacarpal region of the hand on the palm, when the glove 10 is worn.
A first anatomically shaped weight 23 is positioned within the weight receiving pocket 20 and a second anatomically shaped weight 24 is positioned within the second weight receiving pocket 22. The first weight 23, shown more clearly in FIG. 5, includes a convex surface 26 having a waffle configuration formed by regular indentations 28 and a concave surface 30 having a thin flexible pad 32 adhesively affixed to the surface 30. The waffle configuration facilitates the forming of the weight 23 so that it achieves the desired curved anatomical shape. The first weigh 23 is oriented within the first weight receiving pocket so that the concave surface 30 with its pad 32 is adjacent the back of the wearer's hand. The concave surface 30 of the weight 23 conforms to the contour of the back of the wearer's hand, while the pad 32 cushions the hand from the weight to reduce any discomfort in wearing the glove 10. The pad 32 may be constructed of any material useful for cushioning or absorbing shock, such as a 1/8 inch sprip of microfoam plastic. The weight 23 may also be adhesively affixed to the interior surfaces of weight receiving pocket 20 to prevent its movement.
The second anatomically shaped weight 24, shown more clearly in FIG. 6, is kidney shaped. A concave portion 34 of the weight 24 is positioned within the second weight receiving pocket 22 so that it will oppose the base of the thumb when the glove 10 is worn. The weight 24 may also be adhesively affixed within the pocket 22 to prevent its movement. No pad is required to be affixed to second weight 24, since it is adjacent the fleshy surface of the palm of the wearer's hand.
The weights 23 and 24 may be formed from lead in molds to create the desired anatomical shapes. The weight 23 with regular indentation 28 may be inserted in a lead press to create the desired concave-convex shape to conform more readily to the contour of the hand.
In order to be effective for an adult bowler of ordinary size, it has been found that the combined weight of the first weight 23 and the second weight 24 should be at least 24 ounces. Due to many variables, including the weight of the bowling ball used and the level of experience of the bowler, it has been found desirable to vary the combined weight from the minimum of 24 ounces upwards to 36 ounces. A weight greater than 36 ounces is generally not necessary to create the proper counterbalancing force in the weight glove 10. Children could use a weight glove in such a weight range, but it is understood a lighter weight than 24 ounces may be more comfortable for use by a child. Various combinations of the first weight 23 and the second weight 24 may be used to achieve the desired combined weight. For example, in constructing a weight glove 10 having a combined weight of 32 ounces, the first weight 23 on top of the hand may be provided with a weight of 18 ounces and the second weight 24 on the palm of the hand with a weight of 14 ounces.
The first weight receiving pocket 20 or the second weight receiving pocket 22 may be affixed to the sheet 12 of the weight glove 10 by heat sealing means or sewing the pocket 20 to the glove. In the preferred embodiment of the invention shown in FIGS. 2 and 7, the first weight receiving pocket 20 is affixed by heat sealing means and the second weight receiving pocket 22 is stitched to the underside of sheet 12 of the glove 10. In addition, a first elastic strap 36 is sewn along the top of the glove and a second elastic strap 38 is sewn along the bottom of the glove to provide a proper fit of the glove 10 to the hand.
The weight glove 10 of the present invention improves a bowler's ability to maintain body control while delivering a bowling ball. The particular combination of weights 23 and 24 is swung from the axis of the shoulder some distance from the side of the body in a generally rearward and upward direction, as the bowling ball is swung forward. The moment of the counterbalancing effect is produced by the force of gravity acting on the total mass of weights 23 and 24 at some perpendicular distance from the axis, the moment arm of the force. By distally locating weights 23 and 24 over and under the metacarpal region of the hand, the moment arm is optimized for equalizing the moment of force produced by the bowling ball on the opposite side of the body.
The direct result of the improved body balance created by the weight glove 10 is the player's ability to maintain his equilibrium while approaching the foul line to deliver the bowling ball. This has the desirable additional effect of squaring the bowler's shoulders at the foul line during the instant the ball is released for allowing accurate release of the ball. Use of the glove 10 reduces the tendency to rush the foul line and promotes a more consistent release and follow through with a steadier slide-foot position at the foul line. The long accepted good bowling technique promoted by use of the weight glove 10 can give every type of player a more accurate and consistent delivery of the ball on target, which is the object of the game. Participants in the sport of bowling for recreational purposes or for physical exercise will find learning good bowling technique easier by use of the present invention.
Although the preferred embodiment of the invention has been illustrated in the accompanying drawings and described in the foregoing detailed description, it will be understood that the invention is not limited to the embodiment disclosed, it is capable of numerous rearrangements, modifications, and substitutions of materials and elements without departing from the spirit of the invention.
|
A weight glove which positions weights both above and below the metacarpal region of a bowler's free hand. The weights are thus distally located on the hand of the bowler's free arm and are particularly weighted to counterbalance the one-sided pull of the bowling ball. The weights are anatomically shaped to allow the bowler to comfortably use his gloved hand with the weights in place.
| 8
|
FIELD OF THE INVENTION
The present invention relates generally to disk array storage systems, and more specifically to replacing a disk in a disk array.
BACKGROUND OF THE INVENTION
Disk arrays are arrangements of disks that are often configured to enhance reliability and/or performance. Because hard disk operation involves mechanical and electronic components and continuous energy consumption, hard disks have many failure modes, which include mechanical failures, electronic failures, and power failures. To improve a reliability and performance of hard disk storage, arrays of hard disks are formed into systems that may employ disk and data redundancy, data partitioning, disk health monitoring, and parity generation and checking techniques. Data are often stored in patterns on the disks in an array to enhance the speed and reliability with which the data may be accessed.
Redundant Array of Independent Disks (RAID) is a storage technology that combines multiple disk drive components into a logical unit. Data is distributed across the drives in one of several ways called “RAID levels”, depending on a desired level of availability and performance. RAID disk array configurations are a set of standard configurations that distribute data across multiple disks, using striping, mirroring and/or parity techniques, to provide various degrees of reliability and/or performance enhancement. Data striping techniques segment logically sequential data, e.g., a file, such that accesses to sequential segments of the data are made to different physical disks. Disk minoring replicates data across multiple physical disks. Various parity techniques enable the detection and often the reconstruction of erroneous or lost data. RAID 5 is a standard RAID configuration that uses striping and parity techniques to enable the data on any one disk in the configuration to be totally reconstructed from error-free data and parity on remaining disks in the array.
SUMMARY
Exemplary embodiments of the present invention disclose a method and system for reducing a probability of generating an unrecoverable error on a disk array during a disk rebuild. In a step, an exemplary embodiment identifies a disk to be replaced in the disk array, the disk array including a spare disk. In another step, an exemplary embodiment locates a region in the disk array that incurs a high number of reads and writes during a period prior to replacing the disk in the disk array. In another step, an exemplary embodiment scrubs data in a region in the disk array that has incurred a high number of accesses. In another step, an exemplary embodiment replaces the disk identified to be replaced with the spare disk in the disk array. In another step, an exemplary embodiment rebuilds data on the replaced disk on the spare disk in the disk array.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a block diagram of a computer system containing processors and a storage system, in accordance with an embodiment of the present invention.
FIG. 2 is a block diagram of a RAID 5 array containing a spare disk, in accordance with an embodiment of the present invention.
FIG. 3 is a flow diagram that depicts steps taken in preparation for and recovery from a failure in a disk in a RAID 5 array, in accordance with an embodiment of the present invention.
FIG. 4 depicts a block diagram of components of a computing device, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system, method or computer program product. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.” Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer-readable medium(s) having computer readable program code/instructions embodied thereon.
Any combination of computer-readable media may be utilized. Computer-readable media may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of a computer-readable storage medium would include the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. A computer-readable medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e, g., light pulses passing through a fiber-optic cablw), or electrical signals transmitted through a wire.
Program code embodied on a computer-readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.
Computer program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java®, Smalltalk, C++ or the like and conventional procedural programming languages, such as the “C” programming language or similar programming languages. The program code may execute entirely on a user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).
Aspects of the present invention are described below with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks.
The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
Prognostic techniques are often used to anticipate a disk failure before a total failure occurs, enabling a failing disk to be preventively replaced with a spare disk and the data of the failing disk to be reconstructed on the spare disk with minimal impact to overall system operation. Dedicated sparing in a RAID 5 array incorporates a standby spare disk into the array, decreasing down time when a disk in the array is to be replaced by obviating the need for an immediate physical replacement. When data is stored in a RAID 5 array, parity is generated and stored on a disk that is different from the disks on which the data is stored. If a disk fails or is preventively replaced, the parity and data on the remaining disks can regenerate the data that was on the replaced disk and enable the data to be written to a spare disk. This occurs during an array rebuild. A problem occurs if there is a data error on a disk other than a disk that is being replaced. In this case, the parity and data on the remaining disks will regenerate incorrect data during a rebuild, and consequently the data stored on the spare disk will not match the data on the replaced disk, resulting in one or more unrecoverable errors. This problem, which can be caused by a loss of power or a disk failure during a write to a disk, is primarily associated with regenerating a disk in a RAID 5 array and is commonly referred to as the “write hole” problem.
The minimum amount of data that can be written to or erased at once from a hard disk is often a block of data of a constant size that depends on a design of the disk, an operating system in use, and a file system in use. A technique of block-level striping is used in RAID 5 arrays in which data at sequential addresses that is to be written to an array is partitioned into blocks of data and the blocks of data at sequential addresses are written to disks in sequence, e.g., a first block is written to a first disk, a second block is written to a second disk, and so on, wrapping back to the first disk as necessary. While striping provides no data protection, distributing data across disks usually improves performance by enabling disks to access data in a common strip in parallel.
Many systems periodically or opportunistically scrub data in an array to clean parity errors and to refresh a magnetic field (or other physical phenomenon) representing the data. A scrub operation reads data, determines if the data's parity is correct and, if not, rewrites the data with a “write verify” operation. A write verify operation writes data and then immediately reads the data to determine if the data and parity have been correctly written. The data is moved to another region on a disk if the data continues to be incorrectly written. A frequency with which write verifies and data movements are necessary reflect a health of a drive and may lead to a preventive replacement of a disk in an array.
Many systems that store large amounts of data partition data storage media into levels based on access time, with storage in a higher level being logically closer to a processor and having a faster access time than media in a lower level. These storage media are usually smaller in capacity and more costly than media in a lower level. A search for specific data begins at the highest level (nearest to a processor) and, if not found, continues to a next lower level as necessary until the data is found. By moving frequently accessed data up in a storage level hierarchy, an average access time near to that of fast media with a cost near to that of slower media in a lower level can often be approached. Techniques and applications are available that monitor “hot spots” in a storage hierarchy, regions of recent and frequent access, and move the data associated with these regions up in the hierarchy, logically closer to the processors, to enhance performance. Likewise data that has not been recently and frequently accessed may be moved downward to a lower level to free valuable capacity at a higher level. An example application detects and moves hot spots in a hard disk array upward to solid state disk (SSD), in a hierarchy that incorporates both, to enhance performance. SSD mimics an operation of a hard disk with non-volatile semiconductor memory and is significantly faster, more reliable, and more costly than hard disk storage. For example, an IBM Storwize® V7000 storage system includes IBM® System Storage® Easy Tier®, a function that responds to the presence of solid-state drives in a storage system that also contains hard disk drives. The system automatically identifies and moves frequently accessed data from hard disk drives to SSDs, thus placing frequently accessed data in a level of storage that provides a faster access time.
FIG. 1 is a block diagram of a computer system containing processors and a storage system, in accordance with an embodiment of the present invention. FIG. 1 depicts a computer system 101 that includes processors 103 , a hard disk mass storage system 102 , which stores data in magnetic field patterns on rotating disks coated with ferromagnetic material. RAID 5 disk array 104 is a level 5 RAID array that employs sparing. Sparing is a technique whereby an unused spare disk is physically included in an array, to be immediately available if a disk in the array is replaced with the spare disk and the array is rebuilt. RAID 5 disk array 104 incorporates parity and data distribution techniques to enable one disk in the array to be rebuilt using redundant information stored on the remaining disks in the array. Until a disk rebuild is accomplished, a RAID 5 array can continue to operate with one failed disk, but with reduced performance.
Storage system 102 includes hot spot monitor 105 which monitors data usage on RAID 5 disk array 104 . Hot spot monitor 105 identifies and records a hot spot, a location of frequently accessed data during a recent period of time. The record of hot spots direct a scrubbing operation on the hot spots prior to an array rebuild to decrease the probability of a “write hole” error which can lead to permanent data loss.
Storage system 102 includes disk health monitor and scrub system 106 which monitors the frequency with which correctable errors may occur on the disks in RAID 5 disk array 104 . A scrubbing function in disk health monitor and scrub system 106 is used to clean correctable errors by rewriting data that incorporates the correctable errors.
RAID 5 disk array 200 in FIG. 2 depicts RAID 5 disk array 104 in more detail. RAID 5 disk array 200 includes five disks, disk 201 , disk 202 , disk 203 , disk 204 , and a spare disk 205 , in array positions 0 , 1 , 2 , 3 , and 4 respectively. RAID 5 disk array 200 employs sparing with spare disk 205 to facilitate a quick array rebuild when necessary and striping to enable data that is in a common strip across multiple disks to be accessed in parallel, enhancing performance.
Data to be stored on RAID 5 disk array 200 is partitioned into a sequence of blocks of data having consecutive addresses and a parity block. Three blocks of data and a parity block form a strip. A strip is stored on RAID 5 disk array 200 such that one of the blocks of the strip is stored on each disk in the array (except that nothing is stored on the unused spare disk). Therefore, a strip in RAID 5 disk array 200 includes one block of data on each of three disks and a parity block, stored on a fourth disk, that is generated from the three blocks of data. In an example, in RAID 5 disk array 200 , block 206 , block 207 , block 208 , and parity block 209 form a first strip. A second strip includes blocks 210 , 211 , 212 , and 213 . A parity block for the second strip is block 212 , stored on disk 203 , which is generated from blocks 210 , 211 , and 213 . The position of a disk on which a parity block is stored in each succeeding strip on RAID 5 disk array 200 is shifted to the left by one position. When a position of a parity block in a strip reaches position 0 , a next parity block is written to position 3 in the next strip, and continues to rotate through the disk positions in like manner in succeeding strips.
If disk 203 , for example, begins to fail by incurring correctable errors, disk health monitor and scrub system 106 detects an occurrence of a frequency of correctable errors on disk 203 . If a frequency of errors on disk 203 exceeds a threshold, disk health monitor and scrub system 106 may recommend that disk 203 be replaced with spare disk 205 . If a decision is made to replace disk 203 with spare disk 205 , any hot spots identified by disk health monitor and scrub system 106 on remaining disks 201 , 202 and 204 are scrubbed by disk health monitor and scrub system 106 to decrease a probability of incurring a “write hole” error during an array rebuild.
FIG. 3 depicts a sequence of steps by which a probability of an unrecoverable “write hole” error occurring during an array rebuild is decreased. RAID 5 disk array 200 is monitored by disk health monitor and scrub system 106 in step 301 for disk health and disk hot spots. A decision is made by disk health monitor and scrub system 106 in step 302 as to whether a disk in RAID 5 disk array 200 is failing. If a disk in RAID 5 disk array 200 is not failing, monitoring is continued in step 301 . If a disk in RAID 5 disk array 200 is failing, disk health monitor and scrub system 106 scrubs hot spots on disks in RAID 5 disk array 200 in step 303 that are not on the failing disk. For example, if disk 203 is found to be failing, hot spots on disks 201 , 202 , and 204 are scrubbed. In step 304 , a spare disk in the array logically replaces a failing disk. In step 305 the spare disk is rebuilt with the data on failing disk 203 by using data on disks 201 , 202 , and 204 . To correctly reconstruct the data on failing disk 203 , the data on disks 201 , 202 , and 204 must be correct, and the probability that the data on disks 201 , 202 , and 204 is correct is increased by scrubbing hot spots on disks 201 , 202 , and 204 . Each step in a sequence of steps depicted in FIG. 3 may be performed automatically and/or with operator assistance.
FIG. 4 depicts a block diagram of components of computer system 101 in accordance with an illustrative embodiment of the present invention. It should be appreciated that FIG. 4 provides only an illustration of one implementation and does not imply any limitations with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environment may be made.
Computer system 101 includes communications fabric 402 , which provides communications between computer processor(s) 404 , memory 406 , persistent storage 408 , communications unit 410 , and input/output (I/O) interface(s) 412 . Communications fabric 402 can be implemented with any architecture designed for passing data and/or control information between processors (such as microprocessors, communications and network processors, etc.), system memory, peripheral devices, and any other hardware components within a system. For example, communications fabric 402 can be implemented with one or more buses.
Memory 406 and persistent storage 408 are computer-readable storage media. In this embodiment, memory 406 includes random access memory (RAM) 414 and cache memory 416 . In general, memory 406 can include any suitable volatile or non-volatile computer-readable storage media.
Hot spot monitor 105 and disk health monitor and scrub 106 are stored in persistent storage 408 for execution by one or more of the respective computer processors 404 via one or more memories of memory 406 . In this embodiment, persistent storage 408 includes a magnetic hard disk drive. Alternatively, or in addition to a magnetic hard disk drive, persistent storage 408 can include a solid state hard drive, a semiconductor storage device, read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, or any other computer-readable storage media that is capable of storing program instructions or digital information.
The media used by persistent storage 408 may also be removable. For example, a removable hard drive may be used for persistent storage 408 . Other examples include optical and magnetic disks, thumb drives, and smart cards that are inserted into a drive for transfer onto another computer-readable storage medium that is also part of persistent storage 408 .
Communications unit 410 , in these examples, provides for communications with other data processing systems or devices, including resources of computer system 101 . In these examples, communications unit 410 includes one or more network interface cards. Communications unit 410 may provide communications through the use of either or both physical and wireless communications links. Hot spot monitor 105 and disk health monitor and scrub system 106 may be downloaded to persistent storage 408 through communications unit 410 .
I/O interface(s) 412 allows for input and output of data with other devices that may be connected to computer system 101 . For example, I/O interface 412 may provide a connection to external devices 418 such as a keyboard, keypad, a touch screen, and/or some other suitable input device. External devices 418 can also include portable computer-readable storage media such as, for example, thumb drives, portable optical or magnetic disks, and memory cards. Software and data used to practice embodiments of the present invention, e.g., hot spot monitor 105 and disk health monitor and scrub system 106 can be stored on such portable computer-readable storage media and can be loaded onto persistent storage 408 via I/O interface(s) 412 . I/O interface(s) 412 also connect to a display 420 .
Display 420 provides a mechanism to display data to a user and may be, for example, a computer monitor.
The programs described herein are identified based upon the application for which they are implemented in a specific embodiment of the invention. However, it should be appreciated that any particular program nomenclature herein is used merely for convenience, and thus the invention should not be limited to use solely in any specific application identified and/or implied by such nomenclature.
The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
|
Exemplary embodiments of the present invention disclose a method and system for reducing a probability of generating an unrecoverable error on a disk array during a disk rebuild. In a step, an exemplary embodiment identifies a disk to be replaced in the disk array, the disk array including a spare disk. In another step, an exemplary embodiment locates a region in the disk array that incurs a high number of reads and writes during a period prior to replacing the disk in the disk array. In another step, an exemplary embodiment scrubs data in a region in the disk array that has incurred a high number of accesses. In another step, an exemplary embodiment replaces the disk identified to be replaced with the spare disk in the disk array. In another step, an exemplary embodiment rebuilds data on the replaced disk on the spare disk in the disk array.
| 6
|
CLAIM OF PRIORITY
The present application claims priority from Japanese application JP2007-036328, filed on Feb. 16, 2007, the content of which is hereby incorporated by reference into this application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor light emitting diode (LED), an opto-electronic integrated circuit (OEIC), and a method of fabricating the OEIC; and, more particularly, to an integrated semiconductor, which is in a mixed arrangement with a semiconductor integrated circuit performing an electric signal processing and which integrates a high-brightness LED, a phototransistor capable of controlling optical output power/wavelength with a gate voltage, a silicon laser element, a light receiving element, and a waveguide, and methods of fabricating them.
2. Description of the Related Arts
Optical communications are used in broadband networks supporting the Internet industry. Optical transmission and receiving in the optical communications are made possible by employing Group III-V or Group II-VI compound semiconductor lasers.
Although diverse structures have been suggested for compound semiconductor lasers, a double hetero structure is mostly used. In the double hetero structure, two different kinds of compound semiconductors are joined together by fitting a compound semiconductor with a small band gap into a compound semiconductor with a large band gap. In order to form the double hetero structure, a conductive n-type compound semiconductor, a non-doped i-type compound semiconductor, and a p-type compound semiconductor are sequentially epitaxially grown and laminated in a vertical direction on a substrate. It is then necessary to notice a band structure of the non-doped i-type compound semiconductor sandwiched in between the other two compound semiconductors as it is important that the i-type compound semiconductor has a smaller band gap than the n-type and p-type compound semiconductors, a lower conduction band level than the n-type, and a higher valence band level than the p-type. That is, electrons and holes are confined together in the i-type region. Because electrons and holes are likely to be in the same region, it is highly possible that electrons and holes collide with each other and cause pair annihilation, thereby increasing luminescence efficiency. Moreover, because refractive index tends to increase as the band gap gets smaller, light can also be confined within the i-type compound semiconductor by selecting a material having a refractive index of the i-type compound semiconductor lower than a refractive index of the n-type or p-type compound semiconductor. This confined light efficiently induces or promotes recombination of electrons and holes causing a population inversion, which in turn leads to laser oscillation.
With enhancements in optical communications using an efficient light-emitting compound semiconductor, long distance instantaneous information communications are realized in large quantities. Namely, information processing or saving is carried out on an LSI having a silicon backbone, and information transmission is carried out by a laser having a compound semiconductor used as the backbone.
If silicon can be illuminated at high efficiency, then it is very industrially worthwhile because an electronic device and an LED can be integrated together on a silicon chip. To keep abreast with it, researches on the illumination of silicon have expanded and are in progress.
However, it is difficult to illuminate silicon at high efficiency because silicon has an indirect transition type band structure. In the indirect transition type band structure, either a value of momentum at the lowest conduction band energy or a value of momentum at the lowest valence band energy is not zero. In case of silicon, the lowest energy point of the valence band is a point G where a value of momentum is 0, while the lowest energy point of the conduction band is not the point G but exists between the points G and X. To be more specific, suppose k 0 =0.85*p/a, where ‘a’ is a lattice constant. Then, it degenerates to 6 points of (0,0,±k 0 ), (0,±k 0 ,0), (±k 0 ,0,0), as shown in FIG. 1A .
Meanwhile, most of compound semiconductors are called direct transition type semiconductors because the conduction band and the valence band respectively have the lowest energy at the point G.
Next, the following will explain why luminescence efficiency is bad in an indirect transition type semiconductor and why luminescence efficiency is good in a direct transition type semiconductor.
As described earlier, in order to illuminate a semiconductor element, electrons and holes collide with each other and are annihilated, and an energy difference of both has to be emitted as a photon or light. At this time, both the energy conservation law and the momentum conservation law must be satisfied. An electron has energy levels within the conduction band, while a hole has energy levels for electronless regions within the valence band. A difference between them becomes light energy. As the wavelengths of light vary depending on energy, an energy difference between the conduction band and the valence band, i.e., the band gap size, determines the wavelength of light, i.e., color. Viewed in this light, there is not much difficulty in the law of energy conservation being satisfied.
Meanwhile, since a collision between electrons and holes is involved in light emission, it is also crucial that momentum is conserved. According to the quantum mechanics that rules the microscopic world, electrons, holes, and photons are not only wavelengths but also elastically scattering particles, so the law of momentum conversation is satisfied. Momentum is a physical quantity which measures how much force is input to make particles fly away from the site of collision. From the perspective of the dispersion relation of light (ω=ck, where ω is an angular frequency, c is a high velocity, and k is momentum of a photon) or the light energy, one can guess that the momentum of a photon during crystallization is almost zero. This means that light collisions may cause a substance to fly away, their impact on the scattering of the substance is very little, which perfectly coincides with our instincts.
On the other hand, a hole has nearly no momentum because its lowest energy point is also at the point G. However, in case of silicon which is an indirect transition type semiconductor, electrons hardly exist at the point G but at the lowest energy point around X. Thus, silicon has a momentum as large as k 0 =0.85*p/a.
To be short, as far as silicon is concerned, it is impossible to satisfy the momentum conservation law as well as the energy conservation law simply during the electron-hole collisions. Therefore, a phonon which is an oscillating quantum of a photon in crystals was absorbed or emitted to convert only electron-hole pairs into light, trying to satisfy both the momentum and energy conservation laws by any means. Although we are not to imply this mechanism or process does not exist physically, its probability of occurrence is still slim because electrons, holes, photons, and phonons in silicon exhibit a high-dimensional scattering where they collide with each other at the same time. This is primarily why silicon, the indirect transition type semiconductor, is reported to show very poor luminescence efficiency.
On the contrary, a lowest energy point of the conduction band and a lowest energy point of the valence band for most direct transition type compound semiconductors are found at the point G, so the law of momentum conservation and the law of energy conservation are satisfied at the same time. Therefore, luminescence efficiency in compound semiconductors is high indeed.
There has been reported about a transistor laser diode which drives laser in use of a compound semiconductor with a high luminescence efficiency by a bipolar transistor made out of a compound semiconductor (see R. Chan, M. Feng, N. Holonyak, Jr., A. James, and G. Walter, “Applied Physics Letters”, vol. 88, pp. 143508-1-143508-3, 2006).
As mentioned before, even though silicon in the bulk state shows very poor luminescence efficiency, it is also known that the luminescence efficiency increases if silicon is made to a porous state or to nano-sized particles. For example, there is a report that when silicon having been anodized in a hydrofluoric acid solution becomes porous, it emits light at room temperature and in the visible wavelength band (see L. T. Canham, “Applied Physics Letters”, vol. 57, pp. 1046-1048, 1990). The mechanism involved here is not perfectly explained, but many acknowledge the possible importance of the quantum size effect to allow porous silicon to be trapped in a narrow region. Generally, inside a small size silicon, electrons are confined in their regions and do not have a definite amount of momentum, according to the uncertainty principle in quantum mechanics. It is considered that this causes electrons and holes to recombine very easily.
As another way of using silicon, light emitting diode acting as a luminescent element can be fabricated by implanting Er ions during pn junction formed on a Si substrate (see, for example, S. Coffa, G. Franzo, and Priolo, “Applied Physics Letters”, vol. 69, pp. 2077-2079, 1996). When Er ions are implanted into the Si substrate, it creates an impurity orbit which is a spatially localized state. Therefore, if electrons within the conduction band of Si are captured into the impurity orbit, it is possible that their momentums practically become zero and recombine with holes within the valence band to emit light. Since the light emission in result of Er-ion implantation is of a 1.54 μm wavelength, light is likely to propagate without being adsorbed by surrounding silicon. Moreover, this also is a wavelength featuring a low energy loss when a prior art optical fiber is utilized. Therefore, even when technical advances in future may bring a new age of Si-based LEDs using Er ions, many suspect that investment in large-scale facilities will not be necessary because any existing optical network can be employed as it is.
Still another way of using silicon is combining the quantum size effect and the idea of Er-ion for implantation of Er ions into silicon nano-particles, so as to be able to increase luminescence efficiency (see, for example, F.Iacona, G. Franzo, E. C., Moreira, and F. Priolo, “Journal of Applied Physics”, vol. 89, pp. 8354-8356, 2001, or S. Coffa, “IEEE Spectrum”, pp. 44-49, October 2005).
It was a customarily accepted belief about a prior art technique for illuminating silicon that silicon should be put in the porous state or made in nano-size particles according to the quantum size effect, in order to change the structure of a silicon conduction band to the bulk band structure and to lower the momentum from the point k 0 according to the uncertainty principle. However, there is a problem that the surface of a nano-sized silicon particle for example is much more likely to be oxidized and silicon dioxide is produced on the surface. As silicon oxide is an insulator with a very large band gap, the silicon dioxide film formed on the surface consequently makes it difficult to efficiently implant electrons or holes. Therefore, although the prior art silicon light emitting diode may be very high in photoluminescence intensity, it certainly is very low in electroluminescence efficiency. In addition, crystallinity of material used for an emissive layer becomes important for light emission, but unlike single crystalline silicon, silicon nano particles obtained by chemical vapor deposition (CVD) or porous silicon having plural irregular pores formed on the surface due to anode oxidation might suffer deterioration in crystallinity. In effect, poor crystallinity may cause light emission through a defect level. However, the light emission using a defect shows poor efficiency, consequently making it unable to fabricate any device that can put itself to a practical use like information communications.
As mentioned before, a variety of approaches have been made to illuminate silicon by porous silicon or nano-size silicon particles or Er doping, but luminescence efficiency has not yet reached a level for practical applications.
In the meantime, as inventors we came to discover that a light emitting diode featuring high luminescence efficiency can easily be formed, through a prior art silicon process, over a Si substrate, the light emitting diode comprising a first electrode for electrons, a second electrode for holes, and a light emitting section electrically connected to the first and the second electrode, wherein the light emitting section is made out of single crystalline silicon and has a first surface (upper surface) and a second surface (lower surface) facing the first surface, and wherein with respect to (100) plane of the first and second surfaces, the light emitting section crossing at right angles to the first and second surfaces is made thinner. First of all, illumination principles and verification results thereof are provided, followed by objects of the present invention for practical applications.
A principle for efficiently illuminating a Group IV semiconductor such as silicon or germanium equivalent thereto will be explained with reference to accompanying drawings.
Wave function ψ(r) indicating electronic states in crystals of silicon and the like can be expressed in the following equation 1 as a best approximation.
ψ( r )=φ k 0 ( r )ξ( r ) Equation 1
Here, k 0 is a momentum that gives a band valley in a conduction band, r=(x,y,z) indicates a position in space, Φk 0 (r) gives Bloch's relation in a band valley of the conduction band, and ξ(r) is an envelope function. Further, Φk 0 (r) can be expressed in Equation 2 in terms of a periodic function uk 0 (r+a)=u k0 (r) reflecting periodicity against a unit lattice vector (a) in crystals.
φ k 0 ( r )= u k 0 ( r ) e ik 0 ·r Equation 2
As is evident, it is an atom-scale distance function, highly oscillating. Meanwhile, the envelope function ξ(r) describes slowly-varying components in atom scale, and indicates a response to the physical configuration of a semiconductor or externally applied electric fields. Assuming, including the case of ψ(r) as a wave function in semiconductor structures not necessarily having bulk crystals but finite sizes, a satisfactory formulation of ξ(r) can be induced as follows Equation 3.
[ε( k 0 −i ∇)+ V ( r )]ξ( r )= Eξ ( r ) Equation 3
Here, ε=ε(k) indicates a band structure in a bulk of conduction band electrons having the momentum k, in which a sum of a differential operator −i∇ and a momentum k 0 are substituted for the momentum k, i.e., ε(k 0 −i∇). In addition, V=V(r) indicates a potential an electron feels. For instance, if an insulator or a different kind of semiconductor comes in contact with the boundary of a given semiconductor, a potential barrier is made and an electric field is applied by external electric field effects to control a value of V=V(r). For simplicity of description, only changes in z-direction of V are discussed.
For a better understanding, suppose that there is a silicon film formed on a designated plane 100 for a semiconductor. As described before, in a bulk it has a band structure similar to one shown in FIG. 1A , so the valley in a conduction band existing in k z direction (0,0,±k 0 ) is approximate to Equation 4.
ɛ
(
k
)
=
ℏ
2
2
m
t
*
(
k
x
2
+
k
y
2
)
+
ℏ
2
2
m
l
*
(
k
z
∓
k
0
)
2
❘
Equation
4
Here, m* t and m* 1 are effective masses in silicon crystals obtained respectively from a curvature in a direction of the long axis and the short axis for a conduction band valley having a rotary ellipse shape.
Also, Equation 3 may be substituted into Equation 4 to get Equation 5.
[
-
ℏ
2
2
m
t
*
(
∂
x
2
+
∂
y
2
)
-
ℏ
2
2
m
l
*
∂
z
2
+
V
(
r
)
]
ξ
(
r
)
=
E
ξ
(
r
)
❘
Equation
5
By applying the envelope function to Equation 6, Equation 5 can be written in the form Equation 7, provided that (x,y) denotes a direction parallel to the (100) plane, W is a width, and L is a length.
ξ
(
r
)
=
ⅇ
ⅈ
(
k
x
x
+
k
x
y
)
LW
χ
(
z
)
Equation
6
[
-
ℏ
2
2
m
l
*
∂
z
2
+
V
(
z
)
]
χ
(
z
)
=
Δ
E
χ
(
z
)
Equation
7
Here, ΔE is energy in the z-direction, and all electron energies measured from the bottom of a conduction band can be expressed in Equation 8.
E
=
ℏ
2
k
x
2
2
m
t
*
+
ℏ
2
k
y
2
2
m
t
*
+
Δ
E
❘
Equation
8
First of all, it is confirmed that Equation 7 reproduces bulk electronic states. To this end, an answer in continuous state when V(r)=0 may be obtained. This can be confirmed in that with a thickness t as the z-direction, an envelope wave function is then written as shown in Equation 9, and ΔE is as expressed in Equation 10.
χ
(
z
)
=
1
t
ⅇ
ⅈ
k
z
z
Equation
9
Δ
E
=
ℏ
2
(
k
z
∓
k
0
)
2
2
m
l
*
Equation
10
That is, the wave function oscillates severely in a continuously spread state over the entire bulk crystals. At this time, a quantum mechanical expected value of the momentum in the z-direction naturally becomes Equation 11, k z being a momentum operator in the z-direction.
〈
k
^
z
〉
=
∫
ⅆ
3
r
ψ
*
(
r
)
(
-
i
∂
z
)
ψ
(
r
)
=
k
z
±
k
0
❘
Equation
11
As is clear from the equation, in an indirect transition type semiconductor such as silicon, the probability of electrons being far away from the point G in momentum space is overwhelmingly high, which means that electrons move with great momentum.
The present invention is based on facts that if an ultra-thin film having a thickness ‘t’ in the z-direction, the fact that a direct transition type semiconductor in a bulk changes practically into a direct transition type semiconductor by quantum confined effects is used as a basic principle. More details are followed.
For a better understanding, suppose that silicon has a very small thickness ‘t’ in the z-direction and an insulator made out of SiO 2 for example with a large band gap is nearby on the top and bottom along the z-direction to be in contact with vacuum of a great energy barrier or the air. The same effects can be expected by trapping electrons in a narrow area under the influence of the electric field effect for example. In these cases, the wave function of electrons in silicon becomes zero on a vertical interface of the z-direction. Although technically there is always a possibility that effusion of the quantum mechanic wave function exists, because a large energy barrier reduces the effusion exponentially with respect to the distance in the z-direction, the assumption that wave function of electrons in silicon becomes zero on the interface is almost correct in the strict sense. Therefore, even if an externally applied potential is V(r)=0, protons in the envelop function are completely different from a case where ‘t’ is large. In effect, an envelope wave function for quantum-confined electrons and holes can be explained in Equation 12 if n indicating an exponent indicating a discrete energy level is an even number (n=0,2,4, . . . ), while expressed in Equation 14 if n is an odd number (n=1,3, 5 . . . ) regardless of whether the value of an energy level is an even number of an add number.
χ
n
(
z
)
=
2
t
cos
(
π
z
t
(
n
+
1
)
)
Equation
12
χ
n
(
z
)
=
2
t
sin
(
π
z
t
(
n
+
1
)
)
Equation
13
Δ
E
=
ℏ
2
2
m
l
*
π
2
t
2
(
n
+
1
)
2
❘
Equation
14
Needless to say, the energy level is the lowest when n=0. To plot an envelope wave function, the origin of the z-axis was set up as a center of thin film silicon and it was assumed that there existed an interface having an energy barrier of z=±t/2. Before getting into further details, the nature of the envelope wave function X n (z) will be explained first. In case n is zero or an even number, the wave function becomes symmetric with respect to symbol changes in z, i.e., X n (z)=X n (−z). In this example, it is said that the parity is even. On the other hand, in case n is an odd number, the wave function behaves as X n (z)=−X n (−z). In this example, it is said that the parity is odd.
Because of this symmetric structure, the evaluation of the envelope wave function's contribution to momentum yields Equation 15 below.
〈
χ
n
k
^
z
χ
n
〉
=
∫
ⅆ
zx
n
*
(
z
)
(
-
i
∂
z
)
χ
n
(
z
)
=
0
❘
Equation
15
This shows a well-known nature that if X n (z) is differentiated with respect to the z-direction, the original parity of X n (z) is changed, so it becomes zero when integrated with respect to the z-direction. After all, since electrons are strongly trapped along the z-direction, the envelope wave function becomes a standing wave where electrons do not move at all. This is totally contradictory to Equation 9 where the envelope wave function is an exponential function in the silicon bulk state and electrons move the entire bulk crystals with great momentum. One thing to be careful, though, is that all wave functions having taken Bloch functions into consideration are built up by substituting Equation 2, Equation 6 and Equation 13 or Equation 14 into Equation 1, so quantum mechanical expected values of momentum in the z-direction yield Equation 16.
〈
k
^
z
〉
=
∫
ⅆ
3
r
ψ
*
(
r
)
(
-
i
∂
z
)
ψ
(
r
)
=
±
k
0
❘
Equation
16
Namely, if an original semiconductor material is in bulk, the valley of a conduction band is not found at the point G but as (0,0,±k 0 ), so the wave function overall reflects this nature. That is, although electrons seem to be able to move with momentum ±k 0 even in a thin-film semiconductor material, one should be careful to draw hasty conclusions. For example, in case a material is inversely symmetric in crystals like silicon, the valley (0,0,+k 0 ) and the valley (0,0,−k 0 ) are energically equivalent and degenerated. As in this example, when a quantum mechanical state having a degenerated energy level in general is confined to the spatially same area, hybridization occurs between these states. In other words, if there is an energy bond connecting the valley (0,0,+k 0 ) and the valley (0,0,−k 0 ) even for an instant, two discrete levels form a bound orbit and a non-bound orbit. For example, the Coulomb interaction between electrons (this has not been much included in band calculation) works rather strongly between electrons trapped in a narrow area. The interactions between electrons are called an electron correlation and known to cause serious problems including many transit metal oxides such as a high-temperature superconductor. However, this reflects that, in the bulk silicon, sp orbit of an original silicon atom is big, and this fortunately has not caused any serious problems so far. However, when electrons are trapped in a very narrow area where quantum mechanic effects play a crucial role, the Coulomb interaction becomes so strong that it cannot be ignored. Meanwhile, if elements of a Hamiltonian matrix are to be calculated taking the Coulomb interaction into consideration, hybridization occurs in connection between the valley (0,0,+k 0 ) and the valley (0,0,−k 0 ). And, diagonalization of the Hamiltonian matrix exhibits the formation of split orbits, i.e., a bound orbit and a non-bound orbit. This is similar to a H-atom formation process from two adjacent hydrogen atoms, and evaluation methods on this have been available for about 70 years since the quantum mechanics was established by Heitler-London. In the meantime, we first discovered the formation of a bound state understood by Heitler-London is also important for intervalley bonding especially when Group IV semiconductors such as silicon are confined in a narrow area. Moreover, even though no such energy bond existed at all, it was still possible to produce, through a unitary conversion between two states, a standing wave where electrons do not move in the z-axis direction. The following will provide more details on this.
A Bloch state has a property of U− k0 (r)=U k0 (r) due to inversely symmetric crystals, so the Bloch wave function for the valley (0,0,+k 0 ) and the valley (0,0,−k 0 ) can be expressed as Φ k0 (r)=u k0 (r)e ik0z and Φ−k 0 (r)=uk 0 (r)e −ik0z , respectively. Therefore, the e ±ik0z is a part that is going to require attention. For the formation of a new base state using the sum and difference of those wave functions, conversion to Equation 17 preferably takes place based on the unitary conversion U.
U
(
ⅇ
ⅈ
k
0
z
ⅇ
-
ⅈ
k
0
z
)
=
1
2
(
1
1
-
i
i
)
(
ⅇ
ⅈ
k
0
z
ⅇ
-
ⅈ
k
0
z
)
=
2
(
cos
(
k
0
z
)
sin
(
k
0
z
)
)
Equation
17
Thus, one may learn that a change in the wave function for atomic levels can be expressed in terms of a wave function of two standing waves, i.e., 2 1/2 u k0 (r)cos(k 0 z) and 2 1/2 u k0 (r)sin(k 0 z). And, the entire wave function can be arranged as follows:
ψ( r )=√{square root over (2)} u k 0 ( r )cos( k 0 z )ξ( z ) Equation 18
ψ( r )=√{square root over (2)} u k 0 ( r )sin( k 0 z )ξ( z )| Equation 19
Reflecting a fact that an expected value of momentum in the z-axis direction is a standing value yields another equation below.
〈
k
^
2
〉
=
∫
ⅆ
z
ψ
*
(
z
)
(
-
i
∂
z
)
ψ
(
r
)
=
0
Equation
20
Therefore, it is clear that electrons do not move towards the z-axis direction at all. Meanwhile, one should be careful not to misunderstand that an expected value of momentum seems to vary simply by changing the base. In fact, base wave functions like Equation 18 and Equation 19 do not necessarily show intrinsic momentum. That is, matrix elements of a momentum operator may be rearranged as in Equation 21 out of Equation 18 and Equation 19, in which diagonal matrix elements become zero and non-diagonal matrix elements are pure imaginary numbers.
U
(
k
0
0
0
-
k
0
)
U
-
1
=
(
0
ik
0
-
ik
0
0
)
❘
Equation
21
Whether it is physically appropriate for taking such a base is determined entirely depending on the properties of a target material. Although we assume a very thin single crystalline silicon film which is hardly translation symmetric in the z-axis direction, it is better to take the form of standing waves such as v2u k0 (r)cos(k 0 z) or v2u k0 (r)sin(k 0 z), instead of taking the intrinsic state of momentum such as uk 0 (r)e ±ik0z . When bulk silicon is involved, however, uk 0 (r)e ±ik0z is preferably taken because the bulk silicon is translation symmetric. Moreover, in the bulk state, electrons having momentum ±k 0 move very actively inside crystals. At this time, the electrons are strongly scattered by phonons which are oscillating quantum of photons in crystals, and phase of the wave function changes dynamically, so one cannot possibly expect to form the momentum +k 0 and the momentum −k 0 in a coherent state. On the contrary, a wave function that is sufficiently determined even at room temperature can form a standing wave with fixed phase if a very thin single crystalline silicon film for example where electrons are trapped in an extremely narrow area even thinner than a mean free path 1 controlling a scattering length is employed. In a quantitative sense, it means that a standing wave with a perfect matching or compatible size with the narrow area can be formed while an electron wave moves forwards and backwards at high speed in that narrow area.
As explained so far with reference to simple equations, if electrons are confined in an extremely narrow area as in a very thin single crystalline silicon film, electrons in the bulk state or electrons contained in a material, e.g., silicon, having no electrons of a conduction band at the point G do not move in the vertical direction of the thin film. Again, in the quantitative sense, this means that there is no vertical direction for the thin film, so it is rather natural that the vertical motion of electrons on the thin film is absent. In short, although electrons may have been moving at high speed inside crystals in the bulk state, they come to stop on the thin film because there is eventually going to be no direction for them to move along.
This phenomenon is depicted in a band diagram shown in FIG. 1B . Because no movement can be made towards the z-axis direction, the band structure of bulk shown in FIG. 1A is projected on the plane k 2 =0, while a band structure shown in FIG. 1B is formed by the application of a thin film or electric field effects. The band structure similar to one shown in FIG. 1B is essential for designing a field effect transistor in use of silicon and a basis of device physics. This two-dimensionally trapped material is called a two-dimensional electric or magnetic field. Further, a one-dimensional electric or magnetic field can also be generated if a cell structure, not the thin film, is employed.
Assuming that the band structure shown in FIG. 1B is used, bulk electrons having been at the valley (0,0,±k 0 ) of FIG. 1A are now found at the point G in FIG. 1B . Therefore, electrons in this state do not move in the z-axis direction.
Returning to the basic of device physics, the inventors reached a concept that electrons existing at the point G in FIG. 1B recombine with holes efficiently and can be used as a light emitting diode. Therefore, since confined electrons are not free to move around, when they collide with small holes with low momentum existing at the point G, light with low momentum are emitted, without violating both the energy conservation law and the momentum conservation law. As mentioned before, momentum is a measure of how much impact is required for scattering a particle upon a particle colliding with another particle. As inventors, we entrapped electrons into a narrow area to immobilize them and observed that the electrons lose momentum in such state. When the momentum of an electron decreases, the momentum conservation law during scattering is satisfied (this was difficult to achieve by prior art techniques), enabling even Group IV such as silicon semiconductors to efficiently emit light.
Based on this concept, a very thin Si film cut into 1 cm×1 cm size was actually formed on a portion of a substrate, and its photoluminescence measurement results are shown in FIGS. 2 , 3 and 4 B. Particularly, FIG. 2 and FIG. 4B show luminescence intensities as a result of photoluminescence. As is seen from the results, a very strong enhancement in the luminescence intensity is observed in the very thin Si film. This intensity, compared with the luminescence by an indirect transition type bulk silicon semiconductor, is higher by several figures. From this, we came to believe that those trapped electrons in a narrow area make Group IV such as silicon semiconductors change into a direct transition type. FIG. 3 shows a peak wavelength of the spectrum obtained by this experiment. This confirms that a bigger wavelength is obtained as much as an energy level being displayed in form of silicon band gap (Equation 4). This implies that the more energy scatters, the greater the band gap, conforming to the principle of the quantum confined effect explained above. Changes in wavelength excitation in result of increased band gaps are shown in FIG. 4A . As described above, silicon can be illuminated at high efficiency by using the plane 100 as a surface, making the silicon film thinner, and practically setting the point G as a valley of energy.
Next, we performed verification experiments on electroluminescence by fabricating a light emitting diode based on the structure described above.
FIG. 5A-FIG . 5 H show cross sectional structures of a light emitting diode in order of fabricating process. In addition, FIG. 6A-FIG . 6 H are diagrams showing the fabricating process, seen from the top of an SOI substrate. Here, FIGS. 5A-5H are horizontal cross-sectional views of FIGS. 6A-6H , respectively. For example, FIG. 5H shows a cross-sectional structure of FIG. 6 H(a) cut along a plane 13 . Moreover, FIG. 7 is a diagram showing a cross-sectional structure of FIG. 6 H(a) cut along a plane 14 . A complete form of the device is shown in FIGS. 5H , 6 H(a) and (b), and 7 .
The following sequentially explains a fabricating process.
As shown in FIG. 5A , an SOI (Silicon On Insulator) substrate used as a support base plate is first prepared by sequentially laminating a silicon substrate 1 , a buried oxide (hereinafter referred to as BOX) 2 , and an SOI layer 3 from the bottom to up. When seen from the top of the substrate, only the SOI layer 3 is seen as shown in FIG. 6A . In fact, if the SOI substrate is substantially thin, one may be able to see through to the bottom substrate during the test. A substrate having a plane orientation 100 is used as the SOI layer 3 made out of single crystalline silicon. An initial film thickness of the tested SOI layer 3 prior to the process was 55 nm. In addition, BOX 2 had a film thickness of about 150 nm.
Next, a resist is coated and exposed by a mask through photolithography, leaving out only a desired region of the resist. An anisotropic dry etching is performed to obtain the mesa-shaped SOI layer 3 as shown in FIG. 5B and FIG. 6B . For simplicity of description, only one element is shown in the drawings, but it would be needless to say that a large number of elements are actually formed over a substrate, and many elements can be integrated at high productivity through the silicon process.
Although not shown in the drawings, the anisotropic dry etching is carried out further to make corners of the mesa-shaped SOI layer 3 round. By rounding the corners, a subsequent oxidation process can be performed entirely including the etched portion where a tensile stress is easily gathered, interfering with the oxidation. If the corners are not removed or rounded, more current flows into this SOI layer 3 because of its relatively greater thickness than other parts and as a result, luminescence efficiency is deteriorated.
In order to protect the surface, the surface of the SOI layer 3 is then oxidized by about 15 nm to form a silicon dioxide film 4 as shown in FIG. 5C and FIG. 6C . The silicon dioxide film 4 not only reduces damages on the substrate caused by ion implantation in the following process, but also controls impurities escaping into the air as a result of activation annealing.
Thereafter, resist patterning is carried out by using photolithography to leave the resist only in a desired region, and BF 2 ions are implanted with energy 15 keV and a dose of 1×10 15 /cm 2 to form a P-type impurity implantation region 5 in the SOI layer 3 .
After the resist is removed, resist patterning is carried out again by using photolithography to leave the resist only in a desired region, and P ions are implanted with energy 10 keV and a dose of 1×10 15 /cm 2 to form an N-type impurity implantation region 6 in the SOI layer 3 . This state is shown in FIG. 5D . The top view of FIG. 5D is provided in FIG. 6 D(a). Meanwhile, the ion implanted state is found in FIG. 6 D(b) showing the bottom of the silicon dioxide film 4 . In effect, when examined through an optical microscope during the fabrication, the silicon dioxide film 4 made out of glass looks clear, while an impurity implanted region as shown in FIG. 6 D(b) looks in a slightly different color.
In the ion plantation process, an ion implanted portion on the SOI layer 3 becomes amorphous and is poorly crystallized. Therefore, although not shown in the drawings, it is important to make only the surface of the SOI layer 3 be amorphized and let crystalline silicon remain in an interfacial area between the SOI layer 3 and the BOX 2 . Meanwhile, if acceleration voltage for the ion implantation is set too high, all the ion implanted region on the SOI layer 3 is amorphized, so that the single crystallinity may not be restored even under a subsequent annealing process and the SOI layer 3 is polycrystallized. Therefore, after the ion implantation, crystallinity should be restored by activation annealing and the like. As discussed before, having good single crystallinity is a crucial factor for improving luminescence efficiency.
FIGS. 5 D and 6 D(b) show that the N-type impurity implantation region 6 is formed next to the P-type impurity implantation region 5 , but it is not mandatory to put them close by. When the photolithography using a mask is included in the fabricating process, the two regions may be dislocated. In such case, the P-type impurity implantation region 5 and the N-type impurity implantation region 6 are either separated or overlapped with each other. In this example, a mask pattern is carefully selected to purposely leave a non-ion implanted SOI layer 3 between the P-type impurity implantation region 5 and the N-type impurity implantation region 6 at the same time. A diode having such a non-ion implanted region (i-region) is known as a pin diode. A pn diode and a pin diode, each comprising an ultra-thin silicon layer, are fabricated at the same time for an experiment.
Thereafter, the activation annealing is customarily carried out to active impurities and at the same time, the single crystallinity of the damaged region of the SOI layer 3 due to the ion implantation process may be restored. To reduce the number of processes, however, the activation annealing is not included for the fabricating process in this example, so the impurities are activated at the same time with an oxidation treatment. The reduced number of processes also opens up possibilities for reducing the fabricating cost. Here, the activation and annealing for restoring the single crystallinity may be included as well.
Next, a silicon nitride film 7 is deposited on the front face to a thickness of 100 nm, leading to a state shown in FIGS. 5E and 6E .
Then, resist patterning is carried out by using photolithography to leave the resist only in a desired region. The silicon nitride film 7 is then processed by anisotropic dry etching, leading to a state shown in FIGS. 5F and 6F .
A cleansing process is carried out, followed by an oxidation treatment to make a desired region of the SOI layer 3 as thin as possible. Here, conditions for oxidation are very important. As inventors, we learned that under a prior art oxidation treatment at a temperature of 1000° C. or below, which is often used as the silicon process, the thickness of a silicon dioxide film formed on the P-type impurity implantation region 5 differs by up to twice the thickness of a silicon dioxide film formed on the N-type impurity implantation region 6 . As explained above, the SOI layer 3 needs to be even thinner than the mean free path 1 to enhance luminescence efficiency. For example, the mean free path 1 of silicon is about 10 nm at room temperature. Therefore, the film thickness of the SOI layer 3 has to be 10 nm or less, preferably 5 nm or less. In order to produce a thin, evenly spread film, using impurity ions having different oxidation rates by conductive regions are not allowed. With different oxidation rates, if a conductive region on one side is 5 nm thick, a conductive region on the other side may become too thick or all of it may be oxidized and destroyed. In the meantime, we discovered that even when a 100 nm thick oxide needs to be formed under dry oxidation treatment at an oxidation temperature of 1000° C., a difference between the thickness of the silicon dioxide film formed on the P-type impurity implantation and the thickness of the silicon dioxide film formed on the N-type impurity implantation region 6 may be reduced as small as 1 nm or so.
In this example, an approximately 90 nm-thick silicon dioxide film 8 was formed by the dry oxidation treatment at 1100° C. Consequently, it was possible to reduce the film thickness of an ultra-thin silicon layer to about 5 nm. Moreover, the difference between the film thickness of the N-type doped region and the film thickness of the P-type doped region could be suppressed to 1 nm or less. During the oxidation treatment, one has to watch the film thickness of an ultra-thin silicon layer through a spectrum ellipsometry with an ultra-precision of 1 nm or less, while carefully checking the film thickness of the other silicon layer. For mass production, it is preferred that an oxidation device has a built-in ellipsometry. Moreover, a wafer to be fabricated may preferably have a pre-set pattern for use in film thickness testing. As the luminous region of FIGS. 2 and 3 shows, a pattern for about 1 cm 2 -size testing is provided within a wafer, so as to thoroughly check a film thickness distribution in the wafer surface, while carrying out the oxidation treatment at the same time. In addition, since 1100° C. is high enough to activate ions, impurities that are introduced through ion implantation by this oxidation treatment are readily activated to form a P-type SOI region 9 , an N-type SOI region 10 , a P-type ultra-thin silicon region 11 , and an N-type ultra-thin silicon region 12 . This state is shown in FIGS. 5G and 6G , respectively.
Thereafter, the silicon nitride layer 7 is removed by a cleaning process and by wet etching with hot phosphoric acid. Then, the hydrogen annealing treatment is carried out at a temperature of 400° C., and any bonds produced during the process are H-terminated. FIG. 5H depicts a full cross-sectional view of a finished light emitting diode product. FIG. 6 H( 1 ) is a top view of FIG. 5H , and FIG. 6 H(b) is a bottom view of the silicon dioxide layer 8 to show an implantation pattern. FIG. 7 is a diagram showing the light emitting diode cut along the plane 14 . In detail, FIG. 7 illustrates the formation of the silicon dioxide layer 8 as a result of oxidation of side walls adjacent to the N-type ultra-thin silicon region 12 .
Finally, a desired wiring is carried out to complete the formation of a high-efficiency silicon light emitting diode on the silicon substrate 1 .
FIG. 8 diagrammatically shows how to measure LED properties having the structure described above. A probe 15 is connected to the P-type SOI region 9 , while a probe 16 is connected to the N-type SOI region 10 . Diode properties can be obtained by flowing current between the probe 15 and the probe 16 . A threshold value of the current-voltage characteristics reflects an increment of the band gap shown in FIG. 4A . A proportional dependence of band gap shown in FIG. 4A on the film thickness was observed even in film thicknesses of the P-type and N-type ultra-thin silicon regions 11 and 12 which are differently designed as 13.6 nm, 6.3 nm, 4.0 nm, and 1.3 nm. FIG. 4B shows a spectrum by photoluminescence. As is evident from the drawing, as the SOI film thickness in the ultra-thin silicon region decreases, the luminescence intensity sharply increases. And, luminescence 17 occurs, as shown in FIG. 8 , in the P-type ultra-thin silicon region 11 , the N-type ultra-thin silicon region 12 , and an interface therebetween. For a better understanding, the luminescence 17 overlapped with an upper portion of the P-type ultra-thin silicon region 11 and an upper portion of the N-type ultra-thin silicon region 12 is not shown, but it is needless to say that luminescence 17 takes place on the upper portions as well. The luminescence 17 also proceeds in a direction parallel to the substrate, as illustrated in FIG. 8 .
Next, FIGS. 9A-9F respectively shows a contrast luminescent image superimposed with an optical image of a device element being photographed at the same time, under forward bias conditions applying bias voltages of 0, 1, 2, 3, 4, and 5V to the PN junction, where the image is. Here, the element has a width W of 100 μm and an ultra-thin silicon film has a length L (sum of lengths of the P-type ultra-thin silicon region 11 and the N-type ultra-thin silicon region 12 ) of 10 μm. A grayish band portion in the vertical direction between the probe 1 and the probe 2 in FIG. 9A is an area where the P-type ultra-thin silicon region 11 and the n-type ultra-thin silicon region 12 are formed. Even though luminescence intensities are observed in many areas, the luminescence intensity from an area with the P-type ultra-thin silicon region 11 and the N-type ultra-thin silicon region 12 is definitely stronger, while the luminescence intensity from the relatively thin P-type or N-type SOI region 9 or 10 on the SOI layer is almost zero. These results coincide with the principle discussed earlier that bulk silicon has very week luminescence intensity and the luminescence intensity increases if an ultra-thin silicon layer is employed. In effect, when the number of CCD-observed photons excited from light emission was counted, the luminescence intensity from an ultra-thin silicon layer was definitely larger by several figures than that of a thick silicon layer. Moreover, when luminescence was spectroscopically analyzed by using an insert-filter, it turned out the luminescence intensity was highest around the 1000 nm wavelength and lowest around the 500 nm wavelength. This indicates that light emission in this case is the result of recombination due to the band gap in an ultra-thin silicon layer, not by radiation from a photoelectron and the like having a large kinetic energy, and verifies the principle discussed before is indeed correct.
Next, FIGS. 10A-10F respectively show an image photographed by a low magnification lens under forward bias conditions applying 0, 5, 10, 20, 30, and 40V. Again, it turned out that luminescence intensity was strong from the P-type ultra-thin silicon region 11 and the N-type ultra-thin silicon region 12 , being spread onto a concentric circle.
By using this structure, it becomes possible to obtain a device demonstrating high luminescence efficiency and good productivity and having a Group IV semiconductor as a basic component formed over a silicon substrate for example.
SUMMARY OF THE INVENTION
As discussed earlier, although a light emitting diode is obtained in use of silicon, light needs to be propagated more efficiently as optical communications are taken into consideration. Unfortunately, no one succeeded in obtaining a silicon light emitting diode until now, and a structure for building a light emitting diode within one chip and causing light emission was something no one could imagine.
In view of the foregoing problems, it is, therefore, an object of the present invention to provide a light emitting diode demonstrating high luminescence efficiency and comprising a Group IV semiconductor such as silicon or germanium equivalent thereto as a basic component formed on a silicon substrate by a prior art silicon process, and a fabricating method of waveguide thereof.
It is another object of the present invention is to provide a device based on a Group IV semiconductor, capable of performing laser oscillation by using a waveguide laser cavity, and a fabricating method thereof.
Among many inventions disclosed here, a representative embodiment of the present invention will now be explained briefly as follows.
A light emitting diode according to the present invention comprises a first electrode for implanting electrons, a second electrode for implanting holes, and a light emitting section electrically connected to the first and the second electrode, wherein the light emitting section is made out of single crystalline silicon and has a first surface (upper surface) and a second surface (lower surface) facing the first surface, and wherein with respect to plane orientation (100) of the first and second surfaces, the light emitting section crossing at right angles to the first and second surfaces is made thinner. As such, a waveguide is formed by depositing a material with a high refractive index around a target thin film.
According to the present invention, a light emitting diode demonstrating high luminescence efficiency is easy to form over a silicon substrate for example by using a prior art silicon process, and a waveguide capable of guiding light at high efficiency.
Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, objects and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings wherein:
FIG. 1A shows a band structure in bulk silicon for explaining the operating principle of a light emitting diode according to one embodiment of the present invention;
FIG. 1B shows a band structure in a silicon thin film or during the application of a gate electric field for explaining the operating principle of a light emitting diode according to one embodiment of the present invention;
FIG. 2 shows luminescence intensity from an ultra-thin silicon layer as experimental data for verifying the operating principle of a light emitting diode according to one embodiment of the present invention;
FIG. 3 shows a luminous wavelength from an ultra-thin silicon layer as experimental data for verifying the operating principle of a light emitting diode according to one embodiment of the present invention;
FIG. 4A shows the dependence of luminous wavelength on the film thickness of an ultra-thin silicon layer, based on the operating principle of a light emitting diode according to one embodiment of the present invention;
FIG. 4B shows the dependence of luminous wavelength/intensity on the film thickness of an ultra-thin silicon layer, based on the operating principle of a light emitting diode according to one embodiment of the present invention;
FIGS. 5A through 5H are cross-sectional views stepwisely showing the fabricating process of a light emitting diode for verifying the operating principle of a light emitting diode according to one embodiment of the present invention;
FIGS. 6A through 6H are top views stepwisely showing the fabricating process of a light emitting diode for verifying the operating principle of a light emitting diode according to one embodiment of the present invention;
FIG. 7 is a cross-sectional view of a light emitting diode for verifying the operating principle of the light emitting diode according to one embodiment of the present invention;
FIG. 8 is an explanatory view of a verification test for verifying the operating principle of the light emitting diode according to one embodiment of the present invention;
FIGS. 9A through 9F respectively shows a picture of a light emitting diode in luminescent state for verifying the operating principle of the light emitting diode according to one embodiment of the present invention;
FIGS. 10A through 10F respectively shows a picture of a light emitting diode in luminescent state for verifying the operating principle of the light emitting diode according to one embodiment of the present invention;
FIG. 11 is a planar layout for explaining an integrated light emitting diode according to the first embodiment of the present invention;
FIG. 12 is a planar layout for explaining a light receiving element according to the first embodiment of the present invention;
FIGS. 13 through 18 are schematic cross-sectional views of an integrated light emitting diode for explaining the fabricating process of the device according to the first embodiment of the present invention;
FIGS. 19 through 22 are schematic cross-sectional views of an integrated light emitting diode for explaining other exemplary fabricating processes of the device according to the first embodiment of the present invention;
FIGS. 23 through 27 are schematic cross-sectional views of a light receiving element for explaining the fabricating process of the device according to the first embodiment of the present invention;
FIGS. 28 and 29 are schematic cross-sectional views for explaining the fabricating process of a waveguide according to the first embodiment of the present invention;
FIG. 30 is a planar layout for explaining other exemplary fabricating processes of the waveguide according to the first embodiment of the present invention;
FIGS. 31 through 36 are schematic cross-sectional views for explaining other exemplary fabricating processes of the waveguide according to the first embodiment of the present invention;
FIGS. 37 and 38 are schematic cross-sectional views for explaining the integration of an integrated light emitting diode, a waveguide, and a light receiving element according to the first embodiment of the present invention with a prior art multilayer wiring;
FIGS. 39 through 42 are schematic cross-sectional views for explaining the fabricating process that involves the integration of an integrated light emitting diode, a waveguide, and a light receiving element according to the first embodiment of the present invention with a prior art multilayer wiring;
FIGS. 43 and 44 are planar layouts for explaining other exemplary integrated light emitting diodes according to the first embodiment of the present invention;
FIGS. 45 through 57 are schematic cross-sectional views for explaining other exemplary fabricating processes of an integrated light emitting diode according to the first embodiment of the present invention;
FIG. 58 is a planar layout for explaining an integrated light emitting diode according to the second embodiment of the present invention;
FIG. 59 is a schematic cross-sectional view for explaining an integrated light emitting diode according to the second embodiment of the present invention;
FIGS. 60 through 65 are schematic cross-sectional views for explaining the fabricating process of an integrated light emitting diode according to the second embodiment of the present invention;
FIGS. 66 through 68 are schematic cross-sectional views for explaining an integrated structure of a light emitting device, a waveguide, and a light receiving element according to the second embodiment of the present invention;
FIG. 69 is a schematic cross-sectional view for explaining the structure of an integrated light emitting diode according to the third embodiment of the present invention;
FIG. 70 is a planar layout for explaining the structure of an integrated light emitting diode according to the third embodiment of the present invention;
FIGS. 71 through 81 are schematic cross-sectional view for explaining the fabricating process of an integrated light emitting diode according to the third embodiment of the present invention;
FIG. 82 is a planar layout for explaining the structure of an integrated light emitting diode according to the third embodiment of the present invention;
FIG. 83 is a schematic cross-sectional view for explaining an integrated light emitting diode and a waveguide according to the fourth embodiment of the present invention;
FIG. 84 is a planar layout for explaining an integrated light emitting diode and a waveguide according to the fourth embodiment of the present invention;
FIG. 85 is a schematic cross-sectional view for explaining an integrated light emitting diode, a waveguide, and a light receiving element according to the fourth embodiment of the present invention;
FIGS. 86 through 93 are schematic cross-sectional views for explaining an integrated light emitting diode and a waveguide according to the fifth embodiment of the present invention;
FIGS. 94 and 95 are schematic cross-sectional views for explaining an integrated structure of an integrated light emitting diode, a waveguide and CMOS according to the sixth embodiment of the present invention; and
FIGS. 96 through 111 are schematic cross-sectional views for explaining the fabricating method of an integrated structure of an integrated light emitting diode, a waveguide and CMOS according to the seventh embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the present invention will now be described with reference to the accompanying drawings. In the following description, same drawing reference numerals are used for the same elements even in different drawings. While the present invention has been described with respect to the specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.
Embodiment 1
FIG. 11 is a planar layout for an integrated light emitting diode according to the present invention; FIG. 12 is a planar layout for a light receiving element according to the present invention; and FIGS. 13 through 18 are schematic cross-sectional views for stepwisely explaining the fabricating process of the integrated light emitting diode. In each of the drawings, a cross-sectional view taken along line A-A′ of the planar layout ( FIG. 11 ) is shown on the left hand side, and a cross-sectional view taken along line B-B′ of the planar layout ( FIG. 11 ) is shown on the right hand side.
A 1 μm thick silicon oxide film 1900 is formed on a silicon support substrate 1100 and an SOI wafer having a 100 nm thick single crystalline silicon layer 1120 is thermally oxidized on the silicon oxide film, to form a 20 nm oxide film ( FIG. 13 ). A silicon thin film formation region (fin) and a contact region are formed ( FIG. 14 ) by using an active region pattern 1150 shown in FIG. 11 . Hereinafter, a thin film-shaped, single crystalline region formed in perpendicular to the substrate is called a fin. A silicon surface exposed towards the side of the fin is thermally oxidized ( 1920 ) to set the silicon width formed by the fin to a predetermined thickness (5 nm). At this time, the crystal orientation of the SOI wafer is set to make the exposed silicon surface become a plane 100 ( FIG. 15 ). A resist mask 1800 is formed by a hole pattern 1850 of FIG. 11 , and arsenic is doped by ion implantation method with energy 25 keV and 2×10 15 cm −3 to form an N-type impurity diffusion layer 1200 ( FIG. 16 ). Next, although not shown, a resist mask formed by inverting the pattern 1850 is formed, and boron is doped by ion implantation method with energy 5 keV and 2×10 15 cm −3 to form a P-type impurity diffusion layer 1300 . In this way, a diode having a PN junction is formed. In order to set a desired electric field, a P-N distance may be adjusted to form an i-region between P and N wells, instead of using the inverted mask as in this embodiment.
A 300 nm silicon nitride film is deposited by CVD method, and a waveguide 1500 is processed by using a waveguide pattern 1550 of FIG. 11 . In this configuration, parallely arranged fins are coated with the waveguide 1500 . Here, the term ‘waveguide’ is not limited to a single wavelength, but used as a light path in a broad sense (FIG. 17 ).
A contact hole 1650 ( FIG. 11 ) is formed in the oxide film 1910 to form a metal wiring 1600 (not shown in FIG. 11 ).
With wiring in the P and N regions, a forward bias can be applied to the PN junction. This enables to obtain the luminescence at a junction inside the parallely arranged fins. In case of arranging a plurality of fins, they are spaced away from each other by a half wavelength to more effectively increase luminescence. Moreover, this structure may be covered with a reflection film (to be described) for laser oscillation.
In this embodiment, the waveguide was put in the air, and a difference in refractive index between the silicon nitride film and the air was utilized to be able to confine light in the waveguide. However, a widely used method in ULSI is sealing a multilayer metal wiring or a chip in a package. To be compatible with this, a method shown in FIG. 19 and FIG. 110 may be used. FIG. 24 shows the results obtained in the process of FIG. 17 . Thereafter, a silicon oxide film 1930 is deposited to 1 μm and polishing by CMP is carried out to planarize it. At this time, since the waveguide is made out of a silicon nitride film, the silicon oxide film having a relatively lower refractive index than the nitride film can act as a reflection coating. A contact hole is perforated into a corresponding oxide film to form a metal wiring 1600 . In this manner, an integrated light emitting diode and a waveguide compatible with the prior art ULSI may be formed.
FIGS. 21 and 22 show other waveguide connecting configurations. Following the process shown in FIG. 16 , the silicon oxide film 1910 is removed by wet etching in hydrofluoric acid and the BOX 1900 is etched at the same time to remove an oxide film below the fins. At this time, the fin section is separated from the oxide film as shown in the drawing on the right hand side ( FIG. 21 ). As described before, the silicon nitride film is deposited to cover the entire fin section with the waveguide 1500 ( FIG. 22 ).
An example of light receiving element is shown. The light receiving element has been used until now. FIG. 12 shows a planar layout of the light receiving element. FIGS. 23 through 26 show the fabricating process in reference to its cross-sectional structure. Because the light emitting diode explained earlier and the light receiving element being explained here are integrated on the same wafer, they are originally formed at the same time. They are separately described for convenience in explaining the structure of the integrated light emitting diode. A P-type doped SOI layer 1120 is processed by using an active region pattern 1160 of FIG. 12 . This process ( FIG. 23 ) corresponds to the SOI layer processing illustrated in FIG. 14 . Hereinafter, reference numerals of corresponding processes will be referred in the following description.
An N-type diffusion region 1210 is formed by using a pattern 1860 in FIG. 12 . In addition, a P-type high concentration impurity region 1310 is formed ( FIG. 24 ). A silicon nitride film 1500 waveguide is formed (see FIG. 25 and FIG. 17 ). A light receiving element is obtained by forming a metal wiring on an electrode layer (see FIG. 26 and FIG. 20 ). A PN diode of the light receiving element can be arranged in a horizontal direction ( FIG. 27 ). Meanwhile, if the PN diode is arranged in a vertical direction, an electric field region by the PN junction can be great whereas the width of the electric field by the PN junction is limited depending on the film thickness of the SOI layer.
The structure using the SOI wafer explained here is characterized by having a sufficiently thick BOX 1900 . Therefore, this oxide film may be utilized even for the formation of the waveguide 1500 . As shown in FIG. 28 , the BOX 1900 is processed concurrently with the processing of the waveguide 1500 to obtain a convex shape. A silicon oxide film 1960 , a silicon nitride film 1961 , a silicon oxide film 1962 , and a silicon nitride film 1963 are laminated by CVD to form a high reflection film (HR film), and a clad having the waveguide 1500 as a core layer is formed ( FIG. 29 ). In this way, it becomes possible to trap light in the waveguide 1500 more efficiently. In this case, a well-known HR formation method can also be utilized, wherein the film thickness of a laminate forming the HR is set to ¼ of the wavelength. For example, in case of a 1 μm wavelength, the film thickness of the laminate becomes about 100-200 nm for the silicon nitride film and the silicon oxide film because of refractive index. Since this is done in similar order to the interlayer insulation film used for a prior art LSI wiring process, it is rather convenient to apply the prior art formation process. Moreover, stacking a laminate with different refractive index for increasing the reflection efficiency can be done repeatedly without difficulty.
Sometimes light traveling direction needs to be changed especially when a light emitting diode and a light receiving element are integrated and signal transfer by light is carried out via waveguide. As a representative example, in case that a waveguide is taken out of the integrated light emitting diode in the perpendicular direction to the substrate plane and then pulled in parallel to the substrate plane, the connection part is raised. This structure can equally be applied to the light receiving element. FIG. 30 shows a planar layout of an exemplary withdrawal portion, and FIGS. 31 through 41 stepwisely show the fabricating process in reference to the cross-sectional structures taken along lines A-A′, B-B′, and C-C′ in FIG. 30 . In the drawings, A-A′ is shown on the left, B-B′ is shown on the center, and C-C′ is shown on the right. In the cross-sectional structure, the integrated light emitting diode region or the light receiving element region is shown diagrammatically with reference numeral 1400 . FIG. 31 shows the formation of a nitride film plug, wherein a light emitting element is formed, and the silicon oxide film 1930 is deposited, planarized by CMP, and perforated by a waveguide withdrawal pattern 1560 of FIG. 30 . Finally, the silicon nitride film 1510 is deposited and etched back. It is also possible to utilize the CMP method instead of an etch back technique for this process. The silicon nitride film functioning as a waveguide is deposited by CVD, and a resist pattern 1700 of FIG. 32 is formed by using 1750 shown in FIG. 30 . A nitride film 1500 is then dry etched by using the resist pattern. At this time, etching conditions are selected to create a deposition atmosphere for the reaction product, to thereby make the processed side in an inclined form ( FIG. 33 ).
A resist 1555 is formed ( FIG. 34 ) by the waveguide pattern 1550 of FIG. 30 . The silicon nitride film 1500 is processed by using the resist 1555 as a mask ( FIG. 35 ). The high reflection film 1970 which is a laminate of the silicon oxide film and the silicon nitride film is deposited to cover the waveguide 1500 . Here, the silicon oxide film and the silicon nitride film have refractive index of about 1.5 and 2, respectively. Moreover, by employing silicon oxy-nitride (SiON) whose composition contains nitrogen in the silicon oxide film, refractive index from the silicon oxide film to the silicon nitride film can be designed. As such, a horizontal waveguide 1500 placed over the vertical waveguide 1510 and the oxide film 1930 is connected at an angle, i.e., with a 45-degree reflective plane. A light that is propagated in the normal direction from the integrated light emitting diode to the substrate plane can travel in a different direction, such as, in the direction parallel to the substrate plane. Although this embodiment illustrated the connection from the integrated light emitting diode, the same structure may also be formed in the light receiving element section.
This waveguide formation process is characterized in that it can adopt the ULSI wiring process as it is. This is shown in FIG. 37 by using the cross-sectional structure, which diagrammatically shows a ULSI wiring with a wide metal multilayer wire. The drawing also shows an integrated light emitting diode 1400 and a light receiving element 1410 formed on the BOX 1900 , respectively. As an example of a multi-layer wire, three metal layers 1600 , 1601 , and 1603 are shown. Each of the interlayer insulation films is denoted by reference numerals 1930 , 1931 , and 1932 . Insulation films of the silicon oxide and silicon nitride are used as materials for the waveguide formation process, and they are actually major ingredients during the wiring process up to now. Therefore, they can be introduced to the multi-layer wiring structure of up to now. After the interlayer 1930 is planarized, the vertical waveguide 1510 is formed, similar to the formation of a contact in the metal wiring. This is repeated for every layer of the multi-layer wiring to form a vertical direction waveguide. Needless to say, this can be performed separately from the formation of contact in the metal wiring. Thus, the hole as in the vertical waveguide can be perforated en bloc after the formation of double or multi-layer interlayer film. Because the laminate high reflection layer 1970 can also function as an interlayer insulation film, as shown in the drawing, the metal wiring 1602 can be put on the clad 1970 .
FIG. 38 illustrates a case where a waveguide is formed below the metal wiring. In the drawing, 1600 denotes a metal plug layer, and 1601 is a metal wiring layer formed by a so-called damascene process. When the waveguide is formed, the metal wiring layer is not yet formed. Thus, a high-temperature deposition technique can be applied to deposit the silicon nitride film used as a waveguide, and the refractive index is easily set.
Because the waveguide and the reflection film used here consists of only an insulating matter employed in the prior art silicon process, they can be integrated with the ULSI of up to now. This new structure does not damage electric properties of the ULSI but improves the waveguide properties. FIGS. 39 through 42 stepwisely show the formation of a structure where a waveguide is covered with a high reflection film. An integrated light emitting diode 1400 and a light receiving element 1410 are formed, and a laminate high reflection film 1971 combining an insulating film 1930 , a silicon oxide film, and a silicon nitride film ( FIG. 39 ) is formed. A vertical waveguide 1510 is formed ( FIG. 40 ). By using the waveguide formation process illustrated earlier (see FIGS. 31 through 36 ), a clad 1970 having the waveguide 1500 as a core layer is formed ( FIG. 41 ). FIG. 47 depicts the formation of the metal wiring 1600 in each diode. As the entire area can be covered by the high reflection films 1970 and 1971 , it becomes possible to trap light in the waveguide 1500 more efficiently.
Embodiment 2
In this embodiment, a plurality of fins are employed as an integrated light emitting diode. The fins can be formed, independently of the patterning. A so-called spacer process is employed as follows. FIG. 43 shows an exemplary planar layout, and FIGS. 45 through 60 stepwisely show the fabricating process by using cross-sectional views (A-A′ cross section of FIG. 43 ). This method is based on a dummy pattern 1152 , but the dummy pattern can be arranged in two different forms, i.e., a convex pattern or a hole pattern. FIG. 43 shows a convex pattern, and FIG. 44 shows a hole pattern. According to the fabricating process of this embodiment, after the dummy pattern 1152 of FIG. 43 and FIG. 44 is formed, fins are self-aligned with respect to the dummy pattern. In general, because of the self-alignment, spacers 1202 , 1203 , 1204 , 1205 , 1981 , 1982 , and 1983 used for fin formation are not necessarily found in a photo mask, but they are indicated at pattern positions of the layout after the formation in order to show the arrangement relation.
Referring now to FIG. 45 , a 300 nm silicon nitride film is deposited on a 50 nm thick SOI 1201 , and a convex shape pattern is formed by the hole pattern 1152 shown in FIG. 43 . Here, the convex shape looks like a projected shape 1102 formed on the plane in the cross-sectional view. Meanwhile, if the hole pattern 1152 of FIG. 44 is used, a concave shape is formed instead of the convex shape. Although the process described hereinafter is provided, assuming that the convex pattern is used, the same process is equally applied when the hole pattern is used.
Referring to FIG. 46 , an amorphous silicon 1202 is deposited to a thickness of 10 nm and heated to be crystallized. Because crystal growth occurs in a seed layer of single crystalline silicon 1201 , single crystals 1201 having crystal orientation are obtained below the side of the projected shape 1102 . In this manner, fins are produced. Here, the silicon surface may be thermally oxidized to adjust the film thickness of the fin to a predetermined thickness. The silicon nitride film 1981 is deposited to a thickness of 20 nm and etched by anisotropic dry etching by the deposition thickness to form the silicon nitride film 1981 in side wall spacer shape.
In FIG. 47 , the process explained above is repeated to obtain a laminate structure consisting of thin, amorphous silicon layers 1203 , 1204 , and 1205 and the nitride film spacers 1982 and 1983 .
In FIG. 48 , a photoresist hole pattern is formed by using the pattern 1165 shown in FIG. 43 to etch the laminate film of the silicon nitride film and the silicon thin film and expose the BOX 1900 (not shown). The silicon nitride film 1500 is then deposited to a thickness of 500 nm to cover the integrated light emitting diode.
In FIG. 49 , the deposited nitride film by CMP is planarized to expose a dummy 1102 . By using the pattern 1150 shown in FIG. 43 as a mask, an N-type region is formed below the fin and on the plane 1300 and a P-type region 1200 is formed on the upper portion by ion implantation, so that a PN junction is formed inside the fin in the vertical direction.
In FIG. 50 , a polycrystalline silicon 1240 doped with a P-type high concentration impurity is deposited to a thickness of 50 nm and processed with the pattern 1855 shown in FIG. 43 .
In FIG. 51 , the silicon nitride film 1500 is processed by using the waveguide pattern 1550 to form a waveguide. On the other hand, if a hole pattern is used for the formation of a dummy shown in FIG. 44 , the processing in use of the pattern 1165 which was explained in reference to FIG. 53 and the formation of the waveguide 1500 can be carried out at the same time. That is, a hole is formed by the pattern 1165 shown in FIG. 44 and the silicon nitride film 1500 is deposited by CMP, to obtain a silicon nitride film waveguide of the hole pattern 1165 . In this manner, the formation of the silicon nitride film 1500 having been discussed in FIG. 51 may be omitted.
In FIG. 52 , the silicon oxide film as an interlayer film is deposited and planarized, followed by performing the metal wiring on each electrode.
Even though the PN junction was formed in the vertical direction to enable high density illumination, the same spacer process can be used to form fins on the SOI substrate by etching.
In FIG. 53 , the surface of the SOI substrate 1120 is thermally oxidized to form an oxide film 1905 with a thickness of 20 nm. A dummy pattern 1103 is formed by polycrystalline silicon, and the silicon nitride film 1985 and the polycrystalline silicon 1206 are alternately deposited to produce a thick nitride film 1986 .
In FIG. 54 , a convex region is planarized by CMP to expose an upper portion of the dummy pattern 1103 .
In FIG. 55 , the nitride film is etched by wet etching, and a polycrystalline silicon pattern is formed.
In FIG. 56 , a target mask is etched anisotropically and transferred as a pattern to the oxide film 1905 .
In FIG. 57 , the SOI silicon layer is etched by using the oxide film pattern as a mask to obtain a fin pattern.
This fin pattern is preferably used to form a light emitting diode. In this embodiment, a minute fin pattern was obtained by the laminate film. However, as mentioned earlier in reference to FIG. 43 and others, a mask pattern may be obtained to form fins by the spacer process.
So far, fins were used primarily for forming an integrated light emitting diode, but the integrated light emitting diode can also be obtained by laminating the silicon thin film in parallel to the substrate plane.
FIG. 58 shows a planar layout, and FIG. 59 is a cross-sectional view taken along line B-B′ of FIG. 58 . The following will explain the fabricating process, referring to FIGS. 60 through 65 which are A-A′ cross sections of FIG. 58 .
In FIG. 60 , a 10 nm silicon germanium film 1121 and a 10 nm silicon layer 1120 are epitaxially grown in turn on the SOI substrate 1120 by MBE technique.
In FIG. 61 , a laminate film 1155 is etched by using an active region pattern 1150 of FIG. 58 .
In FIG. 62 , a PN junction is formed by using an ion implantation mask 1850 and its inversed pattern shown in FIG. 58 .
In FIG. 63 , the silicon germanium crystalline layer is selectively etched by using a thin mask pattern 1165 of FIG. 58 , to obtain a hollow shaped thin film structure of the silicon thin film having the PN junction.
In FIG. 64 , the silicon nitride film is deposited and processed by using the waveguide pattern 1550 ( FIG. 58 ). The hollow shaped region that is formed with the silicon thin film has a buried structure by the silicon nitride film.
In FIG. 65 , an interlayer insulation film and a metal wiring are formed to obtain an integrated light emitting diode that integrates a thin film in the vertical direction.
So far, it has been described about the integration of an integrated light emitting diode and a light receiving element on the same chip and the waveguide junction therebetween. Needless to say, it is possible to integrate a light emitting diode and a light receiving element on different chips and connect them with the same waveguide.
In FIG. 66 , the integrated light emitting diode 1400 and the light receiving element 1410 are formed on two wafers, respectively, and a waveguide 1510 is formed. While the waveguide 1510 being exposed, a low reflection film (AR film) 1990 is formed by laminating the silicon oxide film and the silicon nitride film, and both wafers with the AR film interposed therebetween may be joined for waveguide connection.
Moreover, as shown in FIG. 67 , a support base plate of SOI is removed and layers are laminated to obtain a multi-layer structure. At this time, the AR film may be inserted in the junction interface.
In case of connecting a wafer laminate structure with a waveguide, the outer circumference of the waveguide 1500 is covered with the HR film 1970 and the AR film 1990 is placed at the junction. This structure makes it possible to realize high propagation efficiency of light.
Embodiment 3
This embodiment discloses a luminous region expansion method that does not require a laminate film or plural wall-type silicon thin films disclosed in Embodiment 1 and Embodiment 2. In a light emitting diode according to this embodiment, as shown in FIG. 69 , silicon semiconductor regions 3303 and 3304 of different conductive types are arranged adjacent each other on a silicon oxide film 3302 formed on the surface of the silicon substrate 3301 , and a silicon oxide film 3305 is formed in the periphery of the interface of these two semiconductor regions only in such a manner that it covers a portion of the surfaces of the two semiconductor regions. Meanwhile, a silicide 3306 , the compound of silicon and a metal, is formed on the surface of a semiconductor region that is not covered with the silicon oxide film 3305 . In addition, a part of the silicon substrate 3301 , that is, the silicon substrate in a region having the light emitting diode formed thereon, is removed to expose the silicon oxide film 3302 , and a metal layer 3307 functioning as a light reflection film is deposited thereon.
FIG. 70 shows a planar structure of the light emitting diode of this embodiment 3, where 3301 and 3302 denote a silicon substrate and a silicon oxide film formed thereon, respectively. What is on the top surface is the silicon oxide film 3302 . In the drawing, 3304 denotes a conductive type semiconductor region on one side, and 3303 denotes a conductive type semiconductor region on the other side. Moreover, 3305 denotes a silicon oxide region formed in a manner to cover the two conductive type semiconductor regions. Therefore, the light emitting diode of this embodiment is characterized by its planar structure where the circumference of one conductive type silicon semiconductor region is covered by the other conductive type semiconductor region. The junctions in the circumference become luminous regions. Therefore, the luminous area can be expanded simply by increasing the number of junctions as much as desired. At this time, the semiconductor region whose circumference is covered may be laid out in a narrow and long shape instead of a circular shape or a rectangle shape close to a square, so that the length of the luminous PN junction can be increased relatively larger than the layout area. Another characteristic of the light emitting diode of this embodiment is that all the junctions are formed inside the semiconductor regions, and its edges never stick out of the ends of the semiconductor region. Therefore, leak current caused by the edges does not occur. Still another characteristic of the light emitting diode of this embodiment is that the surfaces of the two conductive type semiconductor regions not being covered with the silicon oxide film 3305 are covered with the silicide film. The light generated by this silicide film can easily and efficiently get out through the silicon oxide film 3305 acting like a window. Furthermore, in presence of silicide, uniform voltage can be applied and a stable operation can be realized.
Next, the fabricating method of the light emitting diode of this embodiment is explained, in reference to FIG. 71 and others. First of all, as shown in FIG. 71 , a silicon oxide film 3302 is grown on a surface of the silicon substrate to a thickness of 100-200 nm by a prior art heat oxidation method or the like. Then, a single crystalline silicon film 3310 is laminated on a surface of the oxide film by using a well-known laminating technique. This is a so-called Silicon On Insulator (SOI) structure, which is a kind of silicon substrates used broadly as a part of a semiconductor product such as a high performance micro processor, etc. This embodiment also employs the SOI substrate purchased from a wafer manufacturer, provided that the SOI substrate has plane orientation 100 and is about 50 nm thick.
Next, the silicon thin film 3310 on the oxide film is processed in a desired shape, a convex shape for example ( FIG. 72 ). The size of the silicon thin film 3310 varies depending on the size of a region formed therein and the size of a luminous region. In order to form two different conductive type semiconductor regions in the silicon thin film, a photoresist pattern 3311 to function as an ion implantation mask is first formed by lithography as depicted in FIG. 73 , and only an impurity implanted region is perforated. In this embodiment, arsenic or phosphor is implanted with a dose of 10 14 -10 15 /cm 2 through this opening or hole.
Next, in FIG. 73 , a photoresist pattern used as an ion implantation mask is removed by cleansing. Thereafter, a photoresist pattern 3312 is formed by lithography to cover an already implanted impurity region. Then, boron ions are implanted with a dose of 10 14 -10 15 /cm 2 by using the photoresist pattern as a mask.
Thereafter, as shown in FIG. 75 , the photoresist pattern is removed by cleansing and heated to activate impurities. Through this series of processes, an N-type semiconductor region 3303 with plenty of electrons and a P-type semiconductor region 3304 with plenty of holes are formed. The heating treatment was performed at 900° C. In addition, it is also possible to overlap the N-type and P-type semiconductor regions or interpose a so-called i-region with no impurities between the N-type and the P-type semiconductor region, by adjusting an aperture or a shielding portion on the photoresist mask during ion implantation.
Next, as shown in FIG. 76 , a silicon nitride film 3313 for covering a surface of the substrate is processed by lithography and dry etching to expose the surface of the silicon thin film in the periphery of the interface between the N-type semiconductor region 3303 and the P-type semiconductor region 3304 .
Next, as shown in FIG. 77 , the entire substrate is placed under a high-temperature oxidation atmosphere, so that a silicon oxide film 3305 may selectively grow only on a portion of the surface of the N-type and the P-type semiconductor region not being covered with the silicon nitride film 3313 . This technique is called a selective oxidation of silicon and has already been used by many. The oxidation atmosphere contains hot steam of 1000° C. This hot steam oxidation atmosphere, unlike the oxygen atmosphere, helps a relatively thick oxide film to grow within a short amount of time. The grown oxide film is about 80 nm thick, so a silicon region (this includes an interface between the N-type and the P-type) of about 10 nm in thickness is formed on the partially oxidized silicon thin film.
The silicon nitride film 3313 that became a selected oxidation mask during the process shown in FIG. 77 is selectively removed. To this end, the substrate is impregnated in a hot phosphoric acid solution. It turned out, as shown in FIG. 78 , a semiconductor region is exposed while leaving the grown oxide film.
Next, a metal such as titan, cobalt, nickel and so on is deposited on the entire surface to a thickness of several tens of nanometers and heated at 450° C. under nitrogen atmosphere to remove, by using a hydrogen peroxide containing solution, nonreacted metals that are deposited on the oxide film 3305 . On the other hand, the metal deposited on the silicon thin film causes a chemical reaction under heating and is silicided, so it is not to be removed by a solution. In this manner, a silicide-free structure is formed on the oxide film 3305 , as shown in FIG. 79 . One thing to be careful here is that because silicide has a high resistance, an additional heating operation at 700° C. needs to be performed to lower the resistance of silicide. This technique is already customarily used in the silicon semiconductor process.
Next, as shown in FIG. 80 , only a portion of the silicon substrate (a region having the light emitting diode) is selectively removed. Finally, as shown in FIG. 81 , a metal layer used as a light reflection plate is formed by deposition to complete the fabrication of a light emitting diode. Even though only the fabricating method of a light emitting diode has been explained in this embodiment, it is actually incorporated with the fabricating method of a peripheral semiconductor device or the process for electrically and optically connecting such a semiconductor device with a light emitting diode. Because of this, the metal layer functioning as a reflection plate is adhered to a back surface of the substrate customarily at the end of the process. In case of including a wiring process, a wiring via which current flows into the two semiconductor regions in the light emitting region and a contact hole are formed, as shown in FIG. 82 .
Embodiment 4
In this embodiment, a waveguide for guiding light emitted by the light emitting diode to the light receiving element is mounted. Light emitted by the light emitting diode shows the highest luminescence intensity around 1000 nm wavelength, which is because light emission has occurred as a result of recrystallization due to the band gap of ultra-thin silicon. To trap the light in the waveguide, the light emitting diode 3318 is fully covered with a silicon nitride film 3317 and the silicon nitride film 3317 is arranged in a waveguide pattern on the substrate, similarly to the state shown in FIG. 84 , and a light receiving element 3319 is arranged at the end thereof. The circumference of the waveguide made out of the silicon nitride film 3317 is covered with a silicon oxide film (this is omitted in FIG. 83 for simplicity) having a smaller refractive index than that the silicon nitride film, and light from the light emitting diode does not leak to the outside the nitride film. Meanwhile, a conventional silicon device is used for the light receiving element. FIG. 85 is a cross-sectional view of a chip comprising a group of elements that consists of a light emitting diode 3318 , a light receiving element 3319 , and a silicon nitride film 3317 being integrated together. A typical light receiving element made out of silicon is used for the light receiving element 3319 . Similar to the light emitting diode, the light receiving element is prepared in use of a single crystalline silicon thin film formed over the oxide film on the surface of the substrate 3301 and formed concurrently with others by the prior art silicon semiconductor process.
Embodiment 5
This embodiment is related to a waveguide for efficiently propagating light. First of all, as shown in FIG. 86 , a silicon oxide film 3320 is deposited as an interlayer insulation film in a manner that it covers the entire light emitting diode 3318 and then planarized by the prior art CMP. Next, as shown in FIG. 87 , a waveguide 3321 is arranged right above the periphery of two conductive interfaces (a luminous region). As in Embodiment 4, the waveguide is made out of a silicon nitride film and traps light therein. Therefore, the nitride film waveguide 3321 is inevitably covered with a silicon oxide film for example having a small dielectric constant. In the interest of brevity, this is not going to be explained in further detail.
Here, the cross section of the waveguide is almost semicircular. Moreover, the end portion of the waveguide where the light emitting diode and the light receiving element is arranged has a shape of a quarter of a sphere. Therefore, light from the light emitting diode is reflected from the end at high rate to propagate the waveguide. As the other end portion of the waveguide has also a shape of a quarter of a sphere, the light having propagated the waveguide is now reflected from the end of the waveguide and directed nearly perpendicularly to the light receiving element. Further details on the effects of a waveguide configuration of this shape are provided in U.S. Pat. No. 6,868,214B1.
In order to fabricate such a waveguide, a method that is highly compatible with the prior art silicon semiconductor process was employed. A waveguide made out of silicon nitride film will be discussed first, followed by a waveguide made out of silicon oxide film.
For simplicity in description, a cross section without a luminous region is going to be used as an example. As shown in FIG. 88 , a silicon nitride film 3321 is deposited on a surface of the interlayer insulation film 3320 . Next, as shown in FIG. 89 , the nitride film is processed in a rectangular shape by lithography or dry etching of the prior art. Since the silicon nitride film and the silicon oxide film functioning as an interlayer insulation film are dry etched at different speeds, the processing of the nitride film may be interrupted with the oxide film.
Next, the silicon nitride film is deposited by CVD so that a film of even thickness can be deposited over the surface of the rectangular silicon nitride film as well as the surface of the interlayer insulation film. When prior-art anisotropic dry etching is carried out on the deposited nitride film, as depicted in FIG. 90 , a side wall film 3322 with a circumference drawing an arc only on the side walls of the rectangular silicon nitride film 3321 is formed. In the formation of this side wall film, although it is difficult to make the cross section of the waveguide have a perfect hemisphere shape, the anisotropic dry etching method being frequently used in the silicon semiconductor process and the silicon nitride film may be utilized to form side wall films as desired. This approach is actually known to be highly compatible with a silicon semiconductor. The side wall film formation is preferably repeated several times to get a more hemispherical shaped cross section. Another method is to make a waveguide out of glass having a relatively low melting point.
However, to fulfill a role as a waveguide, the waveguide has to be made of a material that has a greater refractive index than the silicon oxide film functioning as an interlayer insulation film and that is capable of sustaining heat treatment (about 500° C.) in the following wiring process. As such, glass 3323 is applied to the surface of the interlayer insulation film 3320 as shown in FIG. 91 and processed with the rectangular waveguide pattern as shown in FIG. 92 , by dry etching of the prior art. And, this is heated at about 600° C. and fluidified to form a waveguide having a hemisphere cross section as illustrated in FIG. 93 .
Embodiment 6
A light emitting diode of this embodiment is easily fabricated by using a silicon thin film, so it can be mixed with a semiconductor element having a silicon substrate, e.g., Metal Oxide Semiconductor Field Effect Transistor (MOSFET), etc. FIG. 94 illustrates a case that both of a light emitting diode and a semiconductor element (a switching element configured with CMOS: nMOSFET and pMOSFET) are formed on a single crystalline silicon thin film on a silicon oxide film 3302 over a substrate. That is, it is the MOSFET with the SOI structure. In the drawing, 3324 denotes a first conductor type silicon thin film, 3325 denotes a second conductor type silicon thin film, 3326 denotes an element isolation oxide film that is a silicon oxide for performing electrical insulation-separation of two MOSFETs, 3327 denotes a gate oxide film of MOSFET, 3328 denotes a gate electrode of MOSFET, 3329 denotes a second conductive type semiconductor region, 3330 denotes a first conductive type semiconductor region, 3331 denotes a buried metal called a plug for electric connection between a wiring and a semiconductor element, and 3332 denotes a wiring metal. These semiconductor elements can be fabricated concurrently with a light emitting diode by applying the typical fabricating process of silicon semiconductor elements.
FIG. 95 depicts a MOSFET formed over a silicon substrate. A single crystalline silicon film formed on an oxide film 3302 over the substrate and the oxide film 3302 are removed to expose the surface of the silicon substrate. In the example shown in FIG. 95 , this silicon substrate is employed to form a MOSFET. However, because the oxide film 3302 has a thickness of 100-200 nm, a stepped difference due to an oxide film is produced between the silicon thin film used for a light emitting diode and the substrate for MOSFET applications. Therefore, according to this embodiment, a silicon was selectively epitaxially grown on the exposed silicon surface and a single crystalline silicon layer having a thickness of 100-200 nm was grown. In consequence, the stepped difference was substantially reduced and the light emitting diode and the semiconductor device could be fabricated at the same time.
Embodiment 7
FIG. 96 and subsequent drawings describe a method for integrating a light emitting diode with an electric device such as MOSFET at the same time. The example shown in FIG. 96 used a SOI substrate having a single crystalline silicon film 3310 formed over a silicon oxide film 3302 . However, there is not much difference in the fabricating process even when silicon substrates without a BOX 3302 in one portion may be used instead as shown in FIG. 95 .
At first, as shown in FIG. 97 , an element isolation oxide film 3326 is formed for electrical insulation-separation of elements. For this process, any of the prior art silicon microscopic processing techniques such as silicon hole processing, silicon oxidation, silicon oxide burial, polishing, etc., can be employed. FIG. 97 illustrates a case that a luminous region forming area (the single crystalline silicon region on the left side), a first conductive type MOSFET forming area (the single crystalline silicon region at the center), and a second conductive type MOSFET forming area (the single crystalline silicon region on the right side) are formed.
First, a light emitting diode is fabricated. As shown in FIG. 98 , a first conductive type region 3304 is formed by ion implantation of the prior art, and a second conductive type region 3303 is formed inside the first conductive type region by ion implantation as well. To be more specific, arsenic ions were implanted in the first conductive type region 3304 with a dose of 10 15 /cm 2 , and boron ions were implanted in the second conductive type region 3303 with a dose of about 10 15 /cm 2 .
Next, as shown in FIG. 99 , a region 3324 used as a base plate for the first conductive type MOSFET is prepared by ion implantation, and a region 3325 used as a base plate for the second conductive type MOSFET is also prepared by ion implantation. To be more specific, phosphor ions were implanted in the base plate area 3324 for the first conductive type MOSFET with a dose of about 10 13 /cm 2 , and boron ions were implanted in the base plate area 3325 for the second conductive type MOSFET with a dose of about 10 13 /cm 2 .
Next, as shown in FIG. 106 , silicon oxidation is carried out to reduce the thickness of a silicon film in the proximity of the interface between the first and the third conductive type luminous areas. At this time, only an oxidized area deposits an apertured silicon nitride film 3313 ( FIG. 100 ). It is placed in an oxidation kiln containing hot moisture of about 1000° C. to oxidize the silicon thin film by about 40 nm only. Then, an oxide film with a thickness of about 80 nm grows and a single crystalline silicon region with a thickness of about 10 nm remains ( FIG. 101 ).
Thereafter, fabrication of MOSFET proceeds. As shown in FIG. 102 , a gate oxide film 3327 of MOSFET is grown by silicon oxidation technique of the prior art. Here, the film thickness was set to about 2 nm.
Next, polycrystalline silicon is first deposited to a thickness of about 250 nm on the entire surface of the substrate to form the gate electrode of MOSFET. It is processed in the MOSFET's gate electrode shape 3328 as shown in FIG. 103 . The processed size is about 90 nm. At this time, it is important that the processing of the gate electrode stops on a thin gate oxide film (i.e., 2 nm).
In order to form a diffusion layer functioning as a source drain of MOSFET, impurities of a different conductive type from the substrate are implanted by using each gate electrode 3328 as a mask. In case of the MOSFET at the center of FIG. 104 , because the substrate contains phosphor, boron ions are implanted in the diffusion layer in a dose of about 10 15 /cm 2 . On the other hand, in the case of the MOSFET at the right, because the substrate includes boron, phosphor or arsenic is implanted in the diffusion layer in a dose of about 10 15 /cm 2 . Each impurity is implanted in the gate electrode, and low resistivity and work function of the gate electrode are determined thereby.
Next, a side wall insulation film is formed only on the side walls of the gate electrode as shown in FIG. 105 , as a step prior to silicidation of areas in the diffusion layer, gate electrode and light emitting diode, which the areas are not covered by an oxide film. To this end, a silicon oxide film or a silicon nitride film is first deposited on the entire surface of the substrate by CVD of the prior art. When anisotropic dry etching is carried out, a side wall insulation film 3333 remains only on the side walls of the rectangular gate electrode as shown in FIG. 105 .
An exposed silicon surface during the formation of the side wall insulation film is washed, and a 20-30 nm thick metal selected from titan, cobalt, nickel, etc., is deposited thereon. And, a heat treatment at around 450° C. is carried out to cause a reaction between silicon and the metal, thereby producing a metal silicate (silicide) 3306 . The silicide is formed only on the exposed silicon surface, and not formed on the side walls of the gate electrode coated with the side wall insulation film 3333 , or on the silicon oxide covering a luminous region in a light emitting diode. Therefore, these areas remain in metal state. Because these nonreacted metals are removed by using a hydrogen peroxide containing solution, silicide is eventually formed only on an interface with silicon as shown in FIG. 106 . However, because silicide is high in resistance in this case, an additional heating treatment at about 750° C. needs to be performed to lower the resistance of silicide. Accordingly, the resistance of the gate electrode and the resistance of the diffusion layer are lowered, while the MOSFET and the light emitting diode is driven at low voltage.
Next, as shown in FIG. 107 , an interlayer insulation film 3334 is deposited in a manner that it covers the light emitting diode and the MOSFET. The interlayer insulation film 3334 is then polished and planarized.
Next, as shown in FIG. 108 , an optical waveguide 3321 is fabricated at an upper portion of a luminous region, as explained before. And, the waveguide is covered with an insulation film having a refractive index smaller than the waveguide, and is planarized. After that, as shown in FIG. 109 , a wiring, a diffusion layer or a gate electrode of MOSFET, and a metal plug for connecting the silicon region of the limit emitting diode are sequentially formed. The metal plug is formed by perforating a contact hole in the interlayer film, filling the contact hole with metals, and scraping by polishing the metal film adhered onto the surface of the interlayer insulation film.
Finally, as shown in FIG. 110 , the wiring is performed in use of aluminum for example, and an aperture (or opening) is formed into a support base substrate of the light emitting section as shown in FIG. 111 . Next, a metal layer functioning as a light reflection plate is formed to complete the fabrication of an opto-electronic integrated circuit (OEIC).
While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
|
A light emitting diode demonstrating high luminescence efficiency and comprising a Group IV semiconductor such as silicon or germanium equivalent thereto as a basic component formed on a silicon substrate by a prior art silicon process, and a fabricating method of waveguide thereof are provided. The light emitting diode of the invention comprises a first electrode for implanting electrons, a second electrode for implanting holes, and a light emitting section electrically connected to the first and the second electrode, wherein the light emitting section is made out of single crystalline silicon and has a first surface and a second surface facing the first surface, wherein with respect to plane orientation (100) of the first and second surfaces, the light emitting section crossing at right angles to the first and second surfaces is made thinner, and wherein a material having a high refractive index is arranged around the thin film section.
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to the cleaning and preventive maintenance of sailboats, and more particularly, to a device for maintaining a spar track for the free running of sail slides and boltropes under sail loadings.
2. Background Information
Sails, supporting spars and rigging form a sailboat system for movement and navigation. A spar can generally be defined as a pole or system of poles used to support sails. Spars are used herein to describe other sail supports such as mast, booms, gaffs and headfoils. The handling of sails to allow navigation of the sailboat, particularly the hoisting and lowering of sails, depends on spar tracks or grooves and mating slides, slugs, boltropes and luffropes.
Tracks can generally be described as elongated slot-like or channel-like fittings having a T-shaped or bottle-shaped profile and are normally longitudinally positioned on a spar. Slides or slugs are usually interchangeably referred to and may be simply described as fittings that interconnect the sail and the spar track to hold the sail thereto.
Similarly, boltropes and luffropes typically function to interconnect and hold the sail to the spar. Boltropes are usually stitched to a bottom edge or foot of a sail, while luffropes are typically stitched to a luff edge or forward edge of a sail. Boltropes and luffropes are substantially equivalent to one another, although boltropes normally are used with different types of spars than luffropes. For instance, boltropes are typically used with boom tracks, while luffropes are normally used with mast tracks. Therefore, boltropes will be defined herein to include luffropes.
A number of spar tracks are fabricated from metal, metal alloy, or plastic materials. Spar tracks so constructed are designed to mate with boltropes and slides fabricated from non-metallic natural materials or non-metallic synthetic materials. Some spar track and mating slide arrangements are completely made of metal, metal alloy or plastic materials. The metal of popular choice for fabricating spar tracks is aluminum. This choice is dictated in part because of aluminum's great strength, durability, light weight and low cost with respect to other marine metals; and because aluminum spars will normally be hollow and comprise extruded aluminum tracks.
Slides and boltropes are inserted within the spar tracks through openings therein. The inserted slides and boltropes cannot become free at the narrow slotted area of a spar track, and thus, are retained within a larger internal portion thereof. Lowering or raising a sail requires the slides and boltrope to slide within the spar track usually under heavy loadings of the sail. As alluded to previously, maintaining the spar tracks for the free running of the slides and boltropes are of prime importance for sail, track and slide preservation, as well as sailboat safety and enjoyment. Impediments to the lowering and raising of sails through the binding, jamming, buckling or breaking of slides and boltropes can be disastrous. This is particularly true on choppy or rough water and windy during conditions.
Friction caused by the effects of weathering and corrosion are the main villains to prevent the free and sure running of boltropes and slides within the spar tracks. A build-up of grime, and when in seawater, salt, is an ongoing problem with tracks and slides fabricated from plastic. Dampness, salt spray and high humidity exposes all metal tracks and metal slides to a constant threat of corrosion and oxidation. Even stainless steel and aluminum fittings will corrode or oxidize under certain circumstances, depending on the alloy used in their manufacture, and the amount of exposure the stainless steel and aluminum receive.
Metal tracks and slides, like all metals used for marine applications, are normally subjected to three types of corrosion, which contributes to causing undesirable friction and related difficulties in sail handling. The three types are galvanic corrosion, electrolyte corrosion and atmospheric corrosion.
Generally, galvanic corrosion occurs when two dissimilar metals, wherein one acts as an anode and the other acts as a cathode, are coated with an electrolyte. An electrolyte can simply be described as a liquid that produces an electric current. The current flows from the anode to the cathode which causes corrosion through deterioration of the anode. Large bodies of freshwater usually carry impurities that can harmfully serve as an electrolytic. Saltwater, however, is a much better conductor than freshwater, and thus, poses a more serious problem to metal spar tracks and slides.
Electrolytic corrosion normally results from an electric current coming from an outside source, such as a leakage due to an improper grounding systems, and is not self-generating. An electrolytic must still be present to carry the current from the anode to the cathode, but the metals do not have to be dissimilar.
Lastly, atmospheric corrosion usually occurs through a presence of corrosive elements such as oxygen, carbon dioxide, sulfur and chlorine with water or dampness. Atmospheric corrosion typically results in etching, pitting and rusting in iron, steel and other ferrous metals. Also, atmospheric corrosion forms greenish or brown oxide films on bronze and brass, as well as causing brittleness in brass. Similarly, it results in pitting and the forming of cloudy or dull oxide streaks or films on aluminum spars with extruded tracks.
As mentioned previously, the results of corrosion-induced pitting, rusting and the forming of oxide films and streaks at the metal tracks and slides, as well as the build-up of salt or grime thereon increases the unwanted friction between surfaces of the tracks and slides. This friction resists the movement of the slides and boltropes and effectively acts to break their movement during sail hoisting or lowering.
In some instances, slides bent or buckled through jamming cause an additional stress to adjoining sail cloth resulting in premature wear, fatigue and subsequent breakdown or failure. Additionally, the build-up of salt or grime or the fouling effects of corrosion within the spar tracks often acts as an abrasive. The abrasive track surface frequently results in harmful chafing and abrasion of the boltrope as it runs through the track, especially when the boltrope is under tension, and there is a likelihood of movement. Unfortunately, boltrope tension and movement are conditions that are almost always present when a sailboat is on the water. Further, metal tracks which discolor through oxidization, in turn, often undesirably discolor or stain the sail cloths. Discolored and stained sailcloth enhances the sail's ability to pick up abrasive dirt and grime and increases its ability to and associated premature failure.
Various approaches to the needs and problems associated with eliminating friction caused by corrosion and weathering at the surfaces of spar tracks and mating slides and boltropes include, for example, the following. Bare metal spars and their tracks are usually washed and treated with a mild abrasive or a sandpaper to remove corrosion, and thereafter, are waxed to reduce friction. However, this surface treatment is extremely difficult to perform once the spar has been stepped or mounted to the sailboat keel or the deck. The upper, narrow, slot-like opening in the spar track makes reaching, cleaning and coating the wider, lower portion of the internal track surface particularly difficult even when the spar is not standing.
Once the spar is stepped, the internal track surface, especially the portion of the track adjacent the mast head, is virtually inaccessible without going aloft in a bosun's chair, climbing steps, or hauling oneself aloft on a halyard. Notably, a bosun chair is typically needed to free both hands to effectively perform the cleaning and maintenance tasks. Trying to enter the bosun's chair from climbing steps at the sparhead while the boat is even gently rocking can result in being pitched over, and thus, can be very risky. Additionally, building or purchasing climbing steps, which are normally welded or riveted to aluminum spars and bolted to wooden spars, are usually a costly option.
Bare metal spar tracks are also painted to form an impervious layer thereon. This layer denies access to the metal by an electrolyte and oxygen and prevents current flow and oxidation. The main shortcomings of paints, resins, lacquers and similar coatings and films is that the coating must be applied to the entire internal surface, that is, every corner, crevice and curve. As previously mentioned, it is extremely troublesome to generally access and coat the internal track surface of a standing spar without going aloft. To coat the entire internal track surface even with the help of a spraying device is difficult whether the spar is standing, or is laying down in a cradle. This shortcoming is greatly intensified when it is realized that preventing microscopic holes supplied by time and abrasion within the protective coatings that allow corrosion to begin is especially tough.
Bare metal tracks, other than stainless steel, are frequently anodized to coat the metal with a corrosive-resistant material. Chrome and gold are sometimes used for this purpose. Unfortunately, scratches or damages of any kind to the anodized surface exposes the metal and initiates corrosion. Also, corrosive-resistent anodic coatings frequently do not protect against direct spray that detrimentally pits the anodized surface with deposits.
To protect anodized surfaces from pitting, they are often initially treated with a clear plastic lacquer or an epoxy paint and then waxed. However, as previously mentioned, the application of paints and other coatings to provide a protective film over the entire internal spar track surface is an arduous task after the spar has been stepped.
Some metals other than the popular aluminum have been selected to fabricate tracks because of their extremely corrosive-resistant characteristics and their excellent strength, such as, monel and titanium. However, these metals are comparatively expensive with respect to aluminum. Other metals are often too heavy for track applications.
Some metal tracks are provided with slides having metal or plastic ball or roller bearings and are mechanically designed to be adjustable under sail loads. However, these slides are typically comparatively complex in construction, are mostly used on large boats from about 35 feet and longer, and are comparatively costly with respect to other slides.
Some spar tracks use plastic and nylon slides. The disadvantage of plastic and nylon slides in seawater is that even a slight coating of salt on them will often stop the movement of the plastic and nylon slides.
To cope with these problems, prior art cleaning, lubricating and waxing devices usually comprised rags and sponges, which are coated with an anti-corrosive material and caused to run inside a spar tracks by tieing the rag or sponge between a downhaul line and a hoisting line. A major disadvantage of such devices, however, is that the rags and sponges do not satisfactorily reach and contact the entire internal surface of the spar tracks.
U.S. Pat. No. 4,278,472 describes an implement for cleaning bolt line tracks in sailboats, which includes a pair of stiff, transversely spaced, insertion cores that are enclosed in a bonded nappy fabric to make a stiff, non-buckling assembly. The implement is connected between a halyard line and a trailing line, and the first core is inserted into the bolt line track. The two lines are worked reciprocally to move the implement along the bolt line track to dislodge material. However, this stiff, non-folding, non-buckling design may not allow substantial conformance to and contact with the entire internal bolt line track surface; may not be adjusted to substantially conform to and engage the entire internal surface after insertion within the track when it initially does not conform to nor engage the track surface; and may not allow the second core to assist the inserted first core in cleaning the upper slot-like area of the bolt line track.
OBJECTS OF THE INVENTION
It is therefore a general object of the present invention to provide a low-cost, easy-to use, device and process to simplify the cleaning and maintenance of spar tracks.
It is another general object to provide a device and process to facilitate and simply the lubricating and waxing of spar tracks.
It is still a general object to provide a device and process to inhibit corrosion of the internal surface of spar tracks.
It is a specific object to provide a low-cost, simply constructed device and simplified process to maintain a spar track to allow the free-running of slides and boltropes under vertical or horizontal sail loadings.
It is another specific object to provide a device and process to clean and maintain of a spar track after the spar is stepped without the need of a bosun's chair, climbing steps, or a need to hoist oneself aloft on a halyard.
It is still a specific object to provide a cleaning and maintenance device for spar tracks that adjustably allows said device to compress and snugly conform to an internal shape of a spar track while maintaining slidable contact therewith.
Additional objects, advantages and novel features of the present invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
SUMMARY OF THE INVENTION
To achieve the foregoing and other objects, and in accordance with the purpose of the invention as embodied and broadly described herein a spar track cleaning and maintenance device comprises: a compressible, working surface for cleaning, lubricating and maintenance of a longitudinally extending, irregularly-shaped, spherical opening defined by the spar track; at least one first compressible, resiliently flexible, cordage member for inserting into the spar track opening and for slidably engaging an internal surface of the track opening; and a control means for adjustably shaping the working surface and the first cordage member upon being inserted within the spar track opening. The control means adjustably shapes the working surface and the first cordage member, which is integrally formed with the working surface, to allow the working surface and the first cordage member to compress and substantially conform to the shape of the internal track surface and to be in slidable engagement therewith. The compressed working surface and the first cordage member upon being slidably moved within the track opening reduce friction at the internal track surface and enhance the sliding of track slides and boltropes when under loadings from the sail.
BRIEF DESCRIPTION OF THE INVENTION
The accompanying drawings, which are incorporated in and from a part of the specification, illustrate the preferred embodiments of the invention and together with the description, serve to explain the principals of the invention. In the drawings:
FIG. 1 is a perspective view of the spar track cleaning and maintenance device constructed in accordance with the invention.
FIG. 2 is a perspective view of the spar track cleaning and maintenance device of FIG. 1 with sides thereof separated illustrating a control means connected thereto in accordance with the invention.
FIG. 3 is a perspective view of the spar track cleaning and maintenance device of FIG. 1 inserted within an extruded track of a hollow aluminum spar before being adjustably compressed to effect cleaning and maintenance in accordance with the invention.
FIG. 4 is a perspective view of the spar track cleaning and maintenance device of FIG. 1 inserted within an extruded track of a hollow aluminum spar upon being adjustably compressed to slidably engage the track opening in accordance with the invention.
FIG. 5 is a cross-sectional, top view of the spar track cleaning and maintenance device of FIG. 1 illustrating a working surface and united first and second cordage members disposed within a spherical-shaped internal, spar track surface.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIGS. 1 and 2, the present invention relates generally to a spar track cleaning and maintenance device 10. Device 10 comprises a compressible or contractible, resiliently flexible, fabric member 12 having suitable characteristics to resist abrasion and chemical attack by cleaning and maintenance materials. Fabric member 12 defines a working surface or bearing surface that is capable of receiving or being impregnated with a friction-reducing material.
As is contemplated and defined herein, a friction-reducing material includes any number of well-known coatings used to protect spar tracks and spar grooves from the harmful effects of weathering and corrosion. The friction-reducing material also includes several well-known materials used to reduce friction between boltropes, slides, spar tracks, and grooves at their surfaces of contact. Such friction-reducing materials include, for example, but are not limited to paints, lubricants, waxes, oils, lacquers, abrasives, resins, gels, soaps and cleaning solvents. Incidently, it will be noted that spar tracks are substantially equivalent to spar grooves, that spar tracks are used interchangeably for spar grooves in the marine art, and therefore, are used herein to define spar grooves.
Fabric member 12 may be manufactured from numerous well-known natural materials such as cotton cloths and woolen cloths, as well as synthetic materials such as nylon, polyester and teflon cloths. Fabric member 12 is preferably manufactured from cotton. However, it will be understood that other suitable materials having adequate compression and tensile characteristics, as well as adequate weave, finish, porosity and abrasiveness, and other characteristics for bearing friction-reducing materials thereon may be used to manufacture fabric member 12, as will occur to those skilled in the art.
Fabric member 12 comprises a rectangular shape and is folded along a longitudinally extending, imaginary centerline 14 to form a sleeve having two sides 16 and 18. The folded fabric member 12 defines two opposed, transversely spaced, longitudinally extending first and second peripheral edges 20 and 22, and two opposed, transversely extending, peripheral edges 24 and 26.
Longitudinal edge 20 and transverse edges 24, 26 for each of the two sides 16 and 18 are preferably permanently attached to one another through serge stitching 28. It will be apparent that longitudinal edge 20 and transverse edges 24, 26 are not limited to being attached with serge stitching. Alternatively, longitudinal edge 20 and transverse edges 24, 26 may be attached through other well known stitches, such as zig-zag stitching or straight stitching.
Moreover, longitudinal edge 20 and transverse edges 24, 26 may also be attached through any number of well-known adhesives or fasteners. Such adhesives and fasteners should be suitable for enabling the attached longitudinal edge 20 and transverse edges 24, 26 to provide little resistance to crushing and distortion. The adhesives and fasteners should also be suitable for receiving tensile and compression forces during cleaning and maintenance applications, while simultaneously inhibiting failure or separation of the longitudinal edge 20 and transverse edges 24 and 26, as will become more apparent hereinafter.
Enclosed within the folded fabric member 12 is a first compressible or contractible, resiliently flexible, elongated, cordage member 30. Cordage member 30 may be fabricated from many well-known natural materials and synthetic materials having the aforesaid suitable flexibility and compression characteristics required for cleaning and maintenance applications. Suitable tensile and strength characteristics, as well as wear-resistent and chemical-resistent characteristics are also desirable. Examples of such materials are nylon, polyester, manilla, sisal, hemp, coir, metal and etc. A preferred cordage material comprises nylon having a double-braid-type weave.
As is best illustrated in FIG. 5, cordage member 30 preferably comprises an external shape that corresponds to the internal shape of the spar track surface. This is accomplished by providing cordage member 30 with a spherical shape for use with spherically shaped tracks, as is depicted in FIG. 5.
Cordage member 30 is disposed within the folded fabric member 12 so as to extend longitudinally in parallel relationship to adjacent edge 22. Additionally, cordage member 30 is preferably attached through stitching to fabric means 12 along a longitudinally extending edge 32 thereof, which edge 32 is transversely spaced from edge 22.
A second compressible or contractible, resiliently flexible, elongated cordage member 34 is disposed within the folded fabric member 12 so as to longitudinally extend in parallel relationship to first cordage member 30. Cordage member 34 is constructed of the same material as cordage member 30, and is preferably attached through stitching to folded fabric means 12 along longitudinally extending opposed edges 36 thereof. Upon inspection of FIGS. 1 and 2, a distance 31 between the two cordage members 30, 34 is sufficiently narrow to allow cordage member 34, when subjected to compression, to substantially slidably contact the slotted portion of the spar track, as will be more fully explained hereinafter.
Referring again to FIGS. 1 and 2, in accordance with the invention, fabric member 12 includes a control or regulator means 38 for adjustably shaping the working surface of fabric member 12. Control means 38 comprise a high-strength, flexible member and notably is preferably fabricated from the same materials used to fabricate the two cordage members 30, 34. Additionally, control means 38 is preferably in the form of a drawline as will be more fully explained hereinafter.
Control means 38 is longitudinally disposed within folded fabric member 12 between the two cordage members 30, 34 so as to extend in parallel relationship therewith. As is best illustrated in FIG. 2, control member 38 also defines a first peripheral end 40 thereof, which is attached to fabric member 12 through stitching adjacent transverse edges 24. A second peripheral end 41 of control means 38 projects from fabric member 12 by means of a cringle or a grommet 42 disposed at side 16 adjacent transverse end 26.
Grommet 42 distributes stress and prevents tearing and is attached to fabric member 12 with well-known fastening techniques. Grommet 42 may be fabricated from any number of well-known corrosive-resistant materials normally used in marine applications. Marine metals having anodic corrosive-resistent, protective coatings; metal alloys designed to resist corrosion; and plastics are suitable materials for manufacturing grommet 42. Grommet 42 is preferably manufactured from brass.
As is best illustrated in FIG. 1, peripheral end 41 of control member 38 is connected to a locking or fastening member 44 through a rope knot 45. Locking member 44 comprises a cylindrical-shaped grip or peg member having an aperture 46 centered between opposed ends thereof. Locking member 44 is received by aperture 46 such that locking member 44 is slidably moveable, back and forth, in a first direction towards grommet 42 and in an opposite direction towards rope knot 45.
While the locking member 44 has been described in connection with a cylindrical-shaped grip fastened to peripheral end 41 of a drawline with a rope knot, one skilled in the art will appreciate that the adjustable, locking arrangement is not necessarily so limited, and that the arrangement may comprise any number of well-known grips suitably for cinching and releasably maintaining fabric member 12 in a compressed condition, as will be more fully explained hereinafter.
Fabric member 12 further defines two longitudinally spaced grommets 48 disposed in a planar portion of fabric member 12, which planar portion extends from cordage member 34 to longitudinal edge 20. Each one of the two grommets 48 is disposed adjacent to a different one of the two transverse edges 24 and 26. Moreover, the two grommets 48 are preferably fabricated from the identical material used to fabricate grommet 42 and are attached to fabric member 12 in the same manner used to attach grommet 42 thereto.
It will now be appreciated that the size of device 10 depends on the specific cleaning and maintenance application being performed, as well as the type and size of the spar track being treated. In the present embodiment, device 10 will be from around about 152 mm (6 in) long to around about 610 mm (24 in) long, and from around about 76 mm (3 in) wide to around about 152.4 mm (6 in) wide.
It will further be appreciated that device 10 is not limited to a folded-sleeve construction. Specifically, device 10 may be fabricated with two completely separated sides 16, 18 with longitudinal edge 22 being attached in any well-known manner suitable for allowing device 10 to satisfactory conform to the internal shape of spar track surface, as will occur to those skilled in the art. In this construction, the remaining edges 16, 18 and 20 would be attached, as previously described.
Moreover, it will be appreciated that device 10 is not limited to always having a second cordage number 34. That is, device 10 may comprise solely the first cordage number 30 in conjunction with the control means 38 to perform cleaning and maintenance, as will become more apparent hereinafter.
The process of using device 10 for cleaning and maintenance of spar tracks may be best understood upon reference to FIGS. 3 through 5. To clean and provide preventive maintenance at an internal and external working surface of a spar track 50, device 10 is initially inserted or bent on to spar track 50 through an opening therein. It will be noted that the specific details of the opening which receives device 10 forms no part of the present invention and has been omitted from the drawing for the sake of clarity and brevity, since such openings are well known in the marine art. It will be further noted that to optimally clean and provide maintenance to a spherically-shaped, internal, spar track surface 56, as depicted in FIG. 5, spherical-shaped cordage members 30, 34 are used.
Upon inserting device 10 within spar track 50, a pulling or a tugging means is attached to each one of the two grommets 48 to enable fabric member 12 to be reversibly moved therein. It is contemplated that one of the pulling means comprises a halyard or similar rope or line normally utilized for hoisting sails, while the remaining pulling means comprises any downhaul line or similar rope normally utilized for lowering sails. Halyards and downhaul lines are well-known in the marine art, and thus, have been omitted from the drawings for the sake of clarity and brevity. The halyard is attached through a rope knot or shackle to one of the two grommets 48, and is pulled to move the fabric member 12 in a first upward direction. Likewise, the downhaul is attached to the remaining grommet 48 through a rope knot or shackle and is pulled to move the fabric member 12 in a second direction opposite to the first direction.
It will now be apparent that sequentially applying pulling forces to the halyard and downhaul lines causes a smooth slipping movement of device 10 within spar track 50 in first and second reversible directions. It will further be apparent that device 10 is not limited to cleaning and maintenance requiring vertical movement, but may be employed to effect horizontal movement as well. For example, the device 10 can be used for cleaning and maintenance applications at a track disposed along a horizontally positioned boom-type spar.
Thereafter, the control means 38 is actuated or operated to adjust or regulate the compression of the external surface of fabric member 12 and cordage member 30 united thereto. A pulling or tugging force is initially applied to the peripheral end of control means 38 through locking member 44. In response to the pulling force, fabric member 12 and cordage member 30 are squeezed within a wide portion 56 of the internal surface of spar track 50 so as to substantially correspond to the shape thereof.
Additionally, cordage member 34 and the associated working surface 33, which transversely extends between cordage members 30, 34 are also squeezed to substantially correspond to the identical shape of the narrow-slot-like portion 58 of the internal track surface. As just mentioned, track surface portion 58 is comparatively smaller or narrower than track surface portion 56, such that, a third portion 60 of the internal track surface, where the two portions 56, 58 merge, is squeezed between the two cordage members 30, 34.
Moreover, transverse surface 33 is caused through the squeezing to be in substantial contact with third internal surface 60. Notably, third portion 60 of the internal spar track surface is defined herein as all bevels or angled or slanted surface areas defined by the merged internal surfaces 56, 58, or other surface portions thereof.
It will now be appreciated that during the operation of control means 38, cordage member 34 shortens and swells so as to form a sinusoidal-like curve or shape, while substantially snugly engaging an external surface 62 of the extruded spar 64 adjacent the slot-like spar track opening 58 therein, as is best illustrated in FIG. 4. Incidently, it will further be appreciated that serge stitching 28 enables the device 10 to be subject to tensile and compression forces, while substantially inhibiting failure or separation of longitudinal edge 20 and transverse edges 24, 26 without a need to use reinforcing material thereabout.
Upon activation of control means 38, the desired level of contraction and snugness is adjustably maintained by slidably moving locking member 44 along peripheral end 41 of control 38, which projects from grommet 42. By this adjustment, locking member 44 is releasably cinched or put in contact with fabric member 12 through a rope knot 66. When in contact with fabric member 12, locking member 44 functions to check tensile forces acting thereon through the compression of fabric member 12, and thereby, prevents the expansion of fabric member 12.
Thereafter, the cleaning and maintenance of spar track is performed by alternately slidably moving the compressed device 10 within spar track 50, back and forth, to and fro, in first and second opposite directions. For this purpose, the movement can be an oscillating, vibratory-type movement, or it can be a sustained slipping-type movement. A sustained movement is performed by initially moving device 10 in a first direction over a substantial longitudinal length of a spar track, and then subsequently reversibly moving the device 10 in an opposite direction.
In accordance with further aspects of operation, fabric member 12 may also be caused to release the friction-reducing material impregnated therein so as to feed onto internal spar track surfaces 56, 58, and 60, as well as external surface 62 after being hoisted aloft. For example, fabric member 12, while impregnated with the friction-reducing material, can be inserted within spar track 50 and be advanced in a first upward vertical direction by the halyard line attached thereto. An additional downhaul line connected to locking member 44 can then be throttably pulled to actuate control means 38. Throttling control means 38 compresses device 10 and measurably or variably releases the impregnated friction-reducing material therein. It is obvious that the released material under the pull of gravity will controllably flow onto and down internal track surfaces 56, 58 and 60 and adjacent external spar track surface 62. It will be evident that during the release of the friction-reducing material, tension will be maintained on the hoisting and trailing lines, as well as on the throttlable downhaul line connected to locking member 44.
Having observed the details of construction and operation of the device 10, it will be apparent that the present invention provides several additional advantages as follows. Device 10 is of simple construction and provides a low-cost simple method for substantially improving the ease of hoisting and lowering of sails by reducing friction between the external sliding surfaces of tracks and slides and boltropes and the sliding surfaces of the spar track so as to prevent jamming, binding and buckling. Device 10 allows cleaning and maintenance of a spar track to reduce friction therein after the spar has been stepped without a need for a bosun's chair, climbing steps, or a need to hoist oneself aloft on a halyard. Device 10 improves an ability to reach and to fully coat the entire internal surfaces of a spar track including all crevices, curvatures, microscopic holes, abrasion and scratches with a friction-reducing material.
Other advantages can also be described. For instance, device 10 improves an ability to inhibit the forming of oxides and associated discoloration of anodized metals, particularly aluminum, which, in turn, improves an ability to minimize an associated discoloration and sailing of sail cloths. Device 10 increases sailing safety by enabling sails to be easily lowered and hoisted. Device 10 simplifies maintenance and cleaning procedures. Device 10 minimizes harmful chafing and abrasion of boltropes at the spar tracks, which, in turn, inhibits premature failure of the sailcloth. Finally, the ability to adjust the compression of device 10 within a spar track allows one device size to be used with spar tracks that initially provide a loose fit with device 10 upon insertion into the spar track without a need to change to a second device having a larger surface area.
The foregoing description of the preferred embodiment of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed; obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.
|
The spar track cleaning and maintenance device comprises: a compressible, working surface for cleaning, lubricating and maintenance of a longitudinally extending, irregularly-shaped, spherical opening defined by a spar track; at least a first compressible, resiliently flexible, cordage member for inserting into the spar track opening and for slidably engaging an internal surface of the track opening; and a control means for adjustably shaping the working surface and the first cordage member upon being inserted within the spar track opening.
The control means adjustably shapes the working surface and the first cordage member which is integrally formed with the working surface to allow the working surface and the first cordage member to compress and substantially conform to the irregular spherical shape of the internal track surface and be in slidable engagement therewith. The compressed working surface and the first cordage member upon being slidably moved within the track opening reduces friction at the internal track surface and enhances the sliding of the mating slides and boltropes when under loadings from the sail.
| 1
|
PRIOR APPLICATION
This current application is a utility application, filed from and benefiting from the earlier filed U.S. Provisional Application No. 61/071,150, filing date Apr. 15, 2008, titled Modified Dimming Led Driver. All of the disclosures of the Provisional application is incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to drivers for illumination devices such as LEDs (light emitting diodes). The use of LEDs in illumination systems is well known. These devices are especially useful for lighting components, systems, and finished goods. LED lighting is a fast growing segment of the lighting industry due to the efficiency, reliability and longevity of LEDs. Product usage applications include but are not limited to interior and exterior signage, cove lighting, architectural lighting, display case lighting, under water lighting, marine lighting, informational lighting, task lighting, accent lighting, ambient lighting and many others. The present invention includes lighting drivers compatible with LED bulbs, color changing LED strips, LED architectural lights, LED color changing disks, LED traffic/warning lights, LED sign lighting modules and the like. Although the preferred embodiments of the invention are discussed in relation to LED devices, it should be understood that the present invention can be applied to other lighting technologies, such as incandescent, plasma, liquid crystal display or the like. Additionally, the present invention can be applied to switching power supply circuits in general where a variable output voltage or current is desired in response to a varying input voltage waveform such as that produced by standard AC dimmers.
BACKGROUND OF THE INVENTION
LEDs are current-controlled devices in the sense that the intensity of the light emitted from an LED is related to the amount of current driven through the LED. FIG. 1 shows a typical relationship of relative luminosity to forward current in an LED. The longevity or useful life of LEDs is specified in terms of acceptable long-term light output degradation. Light output degradation of LEDs is primarily a function of current density over the elapsed on-time period. LEDs driven at higher levels of forward current will degrade faster, and therefore have a shorter useful life, than the same LEDs driven at lower levels of forward current. It therefore is advantageous in LED lighting systems to carefully and reliably control the amount of current through the LEDs in order to achieve the desired illumination intensity while also maximizing the life of the LEDs.
LED driving circuits, and any circuit which is designed to regulate the power delivered to a load can generally be categorized as either linear or active. Both types of circuits limit either the voltage, or current (or both) delivered to the load, and regulate it over a range of changing input conditions. For example, in an automotive environment the voltage available to an LED driving circuit can range from 9V to 15Vdc. A regulator circuit would preferably be employed to keep the current delivered to the LEDs at a relatively constant rate over this wide input range so that the LED output intensity does not noticeably vary with every fluctuation in the system voltage.
Linear regulators are one type of device or circuit commonly employed to accomplish this task. A linear regulator keeps its output in regulation only as long as the input voltage is greater than the required output voltage plus a required overhead (dropout voltage). Once the input to the regulator drops below this voltage, the regulator drops out of regulation and begins lowering its output in response to a lowering input. In a linear regulation circuit, the input current drawn by the circuit is the same as the output current supplied to the load (plus a negligible amount of current consumed in the regulator itself). As the input voltage presented to the linear regulator rises, the excess power delivered to the system is generally dissipated as heat in the regulator. When the input voltage is above the dropout threshold, the power dissipated in the regulator is directly proportional to the input voltage. For this reason, linear regulators are not very efficient circuits when the input voltage is much larger than the required output voltage. However, when this input to output difference is not too great, linear regulators can be sufficient, and are commonly used due to their simplicity, small size and low cost.
Because linear regulators drop out of regulation when the input is below a certain operating threshold, they can also be employed in LED driving circuits to effect a crude dimming function in response to an input voltage which is intentionally lowered with the desire to reduce the LED intensity. The dimming is “crude” in that it is not a linear response for two reasons. First, in the upper ranges of the input voltage above the dropout threshold, the regulator will hold the output in regulation and the LEDs will not dim at all. Once the dropout threshold is reached, the output voltage will drop fairly linearly with a further drop in input. However, LEDs are not linear devices and small changes in voltage may result in large changes in current which correspondingly effect large changes in output intensity. As the voltage applied to an LED is lowered below a certain threshold, no current will flow through the LED and no light will be produced. FIG. 2 is an example of a linear regulator circuit configured to drive and LED load. FIGS. 3 and 4 give an example of the response of this linear regulated LED circuit to a dimmed input voltage.
The lower power efficiency of linear regulators generally makes them a poor choice in large power systems and in systems where the input voltage is much larger than the required LED driving voltage. As such, these systems typically do not employ them. As LEDs have increased in power and luminous output, it has become common to employ driving circuits that are active, meaning the power delivered to the end system is dynamically adapted to the requirements of the load. This results in increased system efficiency and less heat dissipated by the driving circuitry. Such active driving circuits are commonly implemented using switching regulators configured as buck, boost, or buck-boost regulators with outputs that are set to constant-voltage, or constant-current depending on the circuit. Typically, in LED driving applications, the switching regulator circuit is adapted to sense the current through the LEDs, and dynamically adjust the output so as to achieve and maintain a constant current through the LEDs. FIG. 8 depicts a typical buck regulator circuit configured to drive an LED load at a constant current.
Many switching regulator devices have been specifically designed for driving high powered LEDs. Manufacturers have built into these devices, inputs which can be pulsed with a PWM (pulse width modulation) or PFM (pulse frequency modulation) control signal or other digital pulsing methods in order to effect a lowering of the output of the switching regulator specifically designed to dim the LEDs. Some devices also have analog inputs which lower the output to the LEDs in response to an input which is lowered over an analog range. With such dimming capabilities built into the switching regulators, very accurate linear dimming of the LEDs can be achieved. Such dimming is controlled via a network, or some user interface which generates input signals that are converted to the required digital pulses or analog signals that are sent to the switching regulator driver. This method of dimming in LED lighting systems is common. However, it requires control circuitry and user interface equipment which adds a level of cost and complexity to the lighting system.
In many cases, lighting systems and wiring are already installed, and it is desired to replace these lights with LED lights. Or, it is desired to add LED lights to an existing system and have them work in harmony with lights and equipment which are not LED based. There are common household wall dimmers which are employed to dim incandescent lights, and there are high-end theatrical dimming systems which are used to dim entire lighting installations. These types of dimmers only affect the input voltage delivered to the Lights. There is no additional control signal which is sent to them. Therefore, LED lights which are designed to work in these systems must dim in response to a change in the input voltage.
As noted above, linear regulator based LED drivers will dim in response to a lowering of the input voltage. However the dimming is very non-linear and these regulators are inefficient. Switching regulator drivers will also fall out of regulation and dim their output when the input voltage drops below a certain threshold, but as with linear regulators, when the input is above a threshold, their outputs will be held in regulation and the LED intensity will remain unchanged. And, as in linear regulation circuits, when the switcher circuit is out of regulation, the LED response to the lowering output is very non-linear.
An even greater problem with dimming switching regulator drivers is that these circuits need a certain start-up voltage to operate. Below this voltage, the switching regulator either shuts off completely, or provides sporadic pulses to the LEDs as it attempts to start-up, or passes some leakage current to the LEDs which causes them to glow slightly and never dim to zero. In LED circuits employing multiple lights, each driver circuit can have slightly different thresholds, resulting in differing responses at low dimming ranges. As a result, some lights may flicker, some may be off and some may glow below the threshold voltage. This is unacceptable in most lighting systems that are required to dim using standard ac dimming controllers.
There is a need in the industry for an LED driver based on efficient switching regulators which provides a smooth and linear dimming response to the dimming input voltage that is provided with industry standard ac dimmers, and which can dim the LEDs reliably from 100% to completely off.
It is an object of the present invention to provide an efficient high power LED driver circuit utilizing common switching regulators, capable of dynamically varying the current delivered to the LEDs in proportional response to the varying input voltage provided by standard ac dimmers and dimming systems.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph showing a typical relationship of relative luminosity to forward current in an LED.
FIG. 2 is a diagram of a linear regulator circuit as an LED driver.
FIG. 3 is a graph showing the relationship of the luminous intensity of the LEDs versus the input voltage in a linear regulated LED circuit.
FIG. 4 is a graph of the dimming response in a linear regulated LED circuit.
FIG. 5 is an illustration of a typical forward phase control waveform with a dimmer set to half in an ac power system.
FIG. 6 is an illustration of a typical reverse phase control waveform with a dimmer set to half in an ac power system.
FIG. 7 is an illustration of the ac sinewave input and output from an autotransformer set to half.
FIG. 8 is an illustration of a typical buck regulator circuit driving an LED load at a constant current.
FIG. 9 is a block diagram of a Modified Dimming LED driver implemented in a buck regulator circuit.
FIG. 10 is a circuit diagram of one embodiment of the invention implemented in a buck-boost regulator circuit.
FIG. 11 is the power circuit for the Modified Dimming LED Driver shown in FIG. 10 .
SUMMARY OF THE INVENTION
The present invention concerns a driver circuit for LED products, particularly those that employ dimming and color changing effects. An advantage of the present invention is that it enhances the dimming response of the Driver through a voltage sensing and control circuit which controls the output of a power regulator through digital or analog feedback. The present invention provides greater control over illumination intensity for LED lighting systems which must respond to typical changes in input voltage produced by standard ac dimmers. Additionally, the present invention is adapted to high-power LED systems incorporating switching regulator driving circuits, providing these benefits in arbitrarily large power LED systems. Further advantages of the invention will become apparent to those of ordinary skill in the art through the disclosure herein.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 5-7 show the typical shapes of the ac voltage input presented to a light or lighting system by standard ac dimmers. FIG. 5 shows a forward-phase control chopped sinewave typical of most silicon controlled rectifier (SCR) type incandescent wall dimmers. FIG. 6 shows a reverse-phase waveform which is sometimes provided by dimmers made for electronic or capacitive loads. FIG. 7 shows the type of ac voltage waveform presented by an autotransformer, and some higher-end dimming systems designed for theater lighting. In all of these cases, it is the input voltage that is modified (reduced in amplitude or chopped out during part of the sinewave) in order to present a lower average or rms voltage to the load. As explained in the Background section, this type of dimming can cause non-linear and unpredictable results when it is used with a switcher regulator circuit as is often the case in LED lighting products.
The present invention is best understood by starting with a typical implementation of a prior-art switching regulator LED driver circuit. FIG. 8 shows a diagram of a typical buck switching regulator circuit configured to output a constant current to a load. A detailed description of the operation of a buck switching regulator is beyond the scope of this discussion, but can be found in such reference documents as the National Semiconductor application note AN-556, and the article “Understanding Buck Regulators.” (See for example, National Semiconductor Application Note AN-556, September 2002, and “Understanding Buck Regulators”, Super Nade, Overclockers.com—Nov. 25, 2006 MCP1630/MCP1630V High-Speed Pulse Width Modulator Data Sheet MCP1630 Boost Mode LED Driver Demo Board User's Guide)
Referring to FIG. 8 , the rectifier bridge, CR 1 transforms the ac input voltage (which alternates in polarity from positive to negative in a sinusoidal fashion) to a rectified (all positive) voltage to the input VIN of the regulator. The bulk capacitor C 1 provides storage and smoothes out the rectified ac into a dc voltage. The switching regulator U 1 using an internal pass transistor (not shown) will connect the input voltage VIN to the inductor L 1 through U 1 output VSW. This causes current to flow through the inductor L 1 , and the capacitor C 2 begins to build up a charge. As the C 2 voltage builds up, a current will begin to flow through the LED load and feedback resistor R SENSE causing a sense voltage to appear at the U 1 feedback input FB according to the equation FB=I OUT ×R SENSE . An internal comparator circuit (not shown) within U 1 senses when FB reaches a predetermined level, and then disconnects the input VIN from VSW. As the LOAD draws current from the circuit, the capacitor begins to discharge, and the sense voltage FB begins to drop. The switching regulator senses the drop on FB, and then reconnects the input VIN to the inductor L 1 . based on the values of L 1 , C 1 and the sense resistor R SENSE , U 1 will preferably continue connecting and disconnecting the input voltage VIN to the inductor L 1 in order to keep the output at a level which provides the proper feedback voltage FB. This connecting and disconnecting operation in a pulsed fashion causes the output current I OUT to regulate at a constant level which can be shown from the previous equation to be I OUT =FB×R SENSE . The circuit detailed in FIG. 8 is called a constant current output, because it regulates the output current IOUT that is presented to the load.
FIG. 8 shows an additional input, PWM on the switching regulator U 1 which is sometimes available on these regulators, especially recent devices tailored for LED driving applications. This input generally allows the regulator output to be reduced according to the relative duty cycle of the PWM input pulses when such a control signal is presented. These input pulses can represent any digital pulsed modulation technique, provided the frequency and “on” and “off” pulse durations fall within the specified parameter ranges of the regulating device. This input is specifically provided for dimming; however, as explained in the Background section, in the case of an ac input dimmed with standard dimmers, there is no separate control signal available. In these cases, the regulator's PWM input is connected to the VIN so that the regulator U 1 is always operating to regulate the output when there is sufficient voltage on the input VIN.
It is an object of the present invention to preferably create a separate dimming control signal from information extracted from the input voltage in order to intelligently lower the output of the switching regulator driver circuit.
FIG. 9 shows a block diagram of the circuit of FIG. 8 with one example of the added circuitry to create such a dimming signal. The bridge CR 2 rectifies ac input voltage VAC into the positive voltage VRAC. As in the prior art circuit of FIG. 8 , this rectified input is presented to the VIN of the switcher U 2 , and is smoothed to dc via the bulk capacitor C 3 . However, there is preferably an added diode D 4 which isolates the rectified input VRAC so that it can also be presented to a filter circuit U 3 . The filter U 3 further smoothes and averages the VRAC input so that it can be presented to the analog input of a microcontroller U 4 . The filter U 3 may also contain a voltage divider so that the maximum average voltage filtered from the VRAC input (when there is no dimming) will equal the maximum voltage that can be sampled at the analog input ADC_IN of the microcontroller U 4 . When the VAC input is dimmed from a standard dimmer, the VRAC will correspondingly lower, and the filter output VLVL will reflect the dimming level by presenting a lower dc signal to the microcontroller's ADC_IN analog input. The microcontroller is preferably programmed to periodically sample this input, and generate a pulsed output signal PWM which is proportional in relative duty cycle to the dimming level of the original VAC input. This signal PWM is preferably input to the switching regulator U 2 which correspondingly lowers its output and dims the LEDs.
As noted above, the digital pulsed dimming signal which is referenced here as PWM need not be a strict pulse width modulated signal. Any digital modulation method with parameters adhering to the regulator's specifications for this input may be used. One such method commonly used in power regulator circuits, which is also the method chosen in this embodiment, is pulse frequency modulation (PFM). In PFM, both the cycle frequency and pulse widths of the digital signal are manipulated. Within any given cycle, the relative duty factor (% of total cycle time that the pulse is logic “1”) represents the dimming level. However, instead of simply varying this “on” time in a fixed cycle period, the cycle period itself is changed, thus also varying the signal frequency. This can be accomplished by holding the signal's “off” time constant while varying the cycle time, or vice versa. PFM has the added advantage over PWM of distributing the radiated power over a wider frequency range, reducing the radiated electromagnetic noise at any given frequency. Thus, devices can more readily comply with FCC mandated EMI restrictions.
The microcontroller U 4 can be programmed to begin dimming at any level of dimmed input, or may be set to hold the switcher output at maximum until a certain dimming level is sensed on VRAC, in this way providing some buffer against unwanted dimming from spurious fluctuations on the ac input. More importantly, the microcontroller can be programmed so that the LEDs are fully dimmed to off at a point in the range of the dimmed VRAC input when there is still sufficient input voltage for the switcher U 2 to operate (above its startup threshold). In this way, circuit tolerances between multiple LED lights can be accounted for, and the flickering and glowing seen in prior art implementations when dimmed to a low level can be completely eliminated.
It should be noted that although a microcontroller is used to create the PWM signal to the switcher U 2 , other circuits may be used such as simple pulse generators, common 555 Timer chips, or other methods. It should also be noted that although this embodiment is generating a PFM signal, other dimming control signals can be generated such as frequency modulated pulse signals, bit-angle modulated pulses, analog signals, or combinations of control signals such as that presented in U.S. Pat. No. 7,088,059 referenced above, and are within the scope of the invention.
Further modifications and adaptations of the invention can be realized through alternate implementations of the regulator circuit, using similar added input voltage sampling and dimming control circuitry. FIGS. 10 and 11 detail one such embodiment of the invention based on a Boost Mode LED driver circuit provided by Microchip Technology Inc. As shown in FIG. 10 , the regulator circuit is based on the Microchip MCP1630V High-Speed, Microcontroller-Adaptable, Pulse Width Modulator developed for implementing intelligent power systems. A Detailed explanation of the operation of the MCP1630V and the Boost Mode LED driver circuit can be found in the references sited above. However, following is a basic description of this circuit, including the modifications comprising this embodiment of the invention.
The implementation of the regulator circuit in FIG. 10 is a modification of the standard Boost Mode LED driver provided by Microchip in that the extra capacitor C 12 and inductor L 4 have been added to convert the regulator topology to a Buck-Boost configuration. In this configuration, the output voltage required to drive the LED load can be higher or lower than the input voltage provided to the circuit. This particular embodiment of the invention is adapted to drive a series string of five one-watt high-intensity LEDs from a dimmable 12Vac input.
Referring to FIG. 10 , the 12Vac input is first rectified through the Bridge CR 3 , and smoothed by the bulk input capacitor C 5 to produce the 12VDC input. In actual operation, the 12VDC signal may not be a steady DC level, but may have some amount of ripple based on the size of the input capacitance C 5 , and considering the high output current (350 mA) presented to the LED load. Assuming a 12Vac sine wave input, the 12VDC will have a peak voltage of V PEAK =(V IN *√2)−V BRIDGE where V BRIDGE is equivalent to two standard diode voltage drops through the Bridge CR 3 . Therefore, 12VDC will have a peak of about (12*1.414)−(2*0.7)=15.6V. At 3.6 to 4.0V forward voltage drop for the white LEDs intended for this implementation, the five series LED load will require about 18V-20V when driven at the rated 350 mA output, so the regulator will usually be boosting the output voltage in this application.
The resistor R 14 in FIG. 10 serves as the output current sense resistor which presents a voltage at the FB pin of the MCP1630V (U 6 ) that is proportional to the output current being supplied to the LED load, which returns through the LED-connection through R 14 to ground.
The MCP1630V PWM controller (U 6 ) is comprised of a high-speed comparator, high bandwidth error amplifier and set/reset flip flop, and has a high-current driver output (pin VEXT) used to drive a power MOSFET Q 1 . It has the necessary components to develop a standard analog switch-mode power supply control loop. The MCP1630V is designed to operate from an external clock source which, in this embodiment, is provided by a microcontroller (U 5 ). The frequency of the clock provided by the GP 2 output of U 5 and presented to the OSC_IN input of U 6 , sets the buck-boost power supply switching frequency. The clock duty cycle sets the maximum duty cycle for the supply.
The microcontroller U 5 in this embodiment, operates from its own internal oscillator and has an on chip Capture/Compare/PWM (CCP) peripheral module. When operating in PWM mode, the CCP module can generate a pulse-width modulated signal with variable frequency and duty cycles.
In this embodiment, the CCP module in U 5 is configured to provide a 500 kHz clock source with 20% duty cycle. The 20% duty cycle produced by the CCP module limits the maximum duty cycle of the MCP1630 to (100%-20%)=80%. The clock frequency and duty cycle are configured once at the beginning of the microcontroller software program, and then left alone.
The CCP output is also connected to a simple ramp generator that is reset at the beginning of each MCP1630V clock cycle. The ramp generator is composed of transistor Q 2 , resistors R 2 , R 3 and capacitor C 10 . It provides the reference signal to the MCP1630V comparator through its CS input. The MCP1630V comparator compares this ramp reference signal to the output of its internal error amplifier in order to generate a PWM signal. The PWM signal is output through the high-current output driver on the VEXT pin of U 6 . This PWM signal controls the on/off duty cycle of the external switching power MOSFET Q 1 which sets the power system duty cycle so as to provide output current regulation to the LED load.
A resistor voltage divider (R 5 and R 6 ) and filter capacitor C 8 is used to set the reference voltage presented to the internal error amplifier of the MCP1630V for the constant current control and is driven by the GP 5 pin of the microcontroller U 5 . With GP 5 set to logic level 1, the voltage presented to the resistor divider is 3.3V. The voltage present on the VREF input of U 6 will be 3.3V*R 5 /(R 5 +R 6 )=196 mV. Therefore the internal error amplifier of U 6 will trip when the voltage presented to the FB pin reaches 196 mV. This occurs when the LED current=0.196/0.56 (R 14 ). So, with the component values shown in the implementation of FIG. 10 , the regulated LED current is 350 mA.
R 4 and C 11 form an integrator circuit in the negative feedback path of the internal error amplifier in U 6 , providing high loop gain at DC. This simple compensation network is sufficient for a constant current LED driver.
R 9 and R 10 form a voltage divider that is used to monitor the output voltage of the buck-boost circuit. The output of this voltage divider is connected to pin GP 4 of the microcontroller U 5 and monitored in the software program to provide failsafe operation in case the LED load becomes an open circuit. Since the buck-boost power circuit would try to increase (boost) the output voltage to infinity in the case of a disconnected load (the error amplifier in U 6 would never trip), the software program in the microcontroller U 5 monitors the feedback voltage V_FB to ensure it stays at a safe level. In normal operation, the intended 5 LED load would require a maximum of 20V to drive at 350 mA. In this case, V_FB=20V*R 10 /(R 9 +R 10 )=2.2V. If V_FB rises above this level, the microcontroller U 5 can shut off the clock to the MCP1630V U 6 .
L 3 , Q 1 , C 12 , L 4 , D 5 , and C 13 form a basic voltage buck-boost circuit. Details of the operation of a buck-boost regulator circuit are beyond the scope of this discussion, however, will be understood by those skilled in the art. The value of C 13 has been selected to keep the LED current ripple less than 20% at the rated load conditions.
FIG. 11 details the power circuitry used to provide 5V to the MCP1630V (U 6 in FIG. 10 ), and 3.3V to the microcontroller (U 5 in FIG. 10 ). The rectified voltage 12VDC is presented to U 7 , a 5V low drop out (LDO) linear regulator which provides the input voltage VIN to U 6 . The 12VDC is also presented to U 8 , a 3.3V LDO linear regulator which provides the 3.3V to the U 5 microcontroller in FIG. 10 . In this embodiment of the invention, it is desirable to run the microcontroller U 5 at a lower voltage to ensure it has stable power to monitor and control the circuit when the input voltage is dimmed to the point where it is desired to have the LEDs off. The 3.3V Zener diode D 6 in FIG. 11 is used to limit the maximum input voltage presented to the MCP1703 regulator U 8 .
For the circuit of FIGS. 10 and 11 to function as a standard buck-boost regulator and drive a regulated 350 mA current to the output LED load, all that is necessary in the microcontroller U 5 software program is to initialize the CCP module in PWM mode as discussed above, in order to produce the clock to the MCP1630V U 6 , and to drive its output pin GP 5 high in order to provide the voltage reference for the MCP1630V control loop.
However, additional circuitry has been added to preferably allow the microcontroller U 5 to sample the input voltage, and with modifications to the software, intelligently dim the LED output by controlling the MCP1630V U 6 . These modifications, which comprise the invention as implemented in this embodiment, will now be explained.
R 7 , R 8 , and C 6 in FIG. 10 form a voltage divider and filter which samples the rectified input voltage 12VDC from the bridge CR 3 , and presents it to the microcontroller U 5 on input GP 0 . Note that if the bulk capacitor C 5 were large enough to filter the input to DC, the 12VDC voltage level would be 15.6V as explained above, and the voltage at GP 0 of U 5 would be V GP0 =15.6*R 8 /(R 7 +R 8 )=5.2V. However, in this implementation, there is considerable ripple on the 12VDC voltage, and the actual voltage presented to GP 0 of U 5 is much less. The values of these components have been chosen to present 3V to the microcontroller U 5 when the input is 12Vac. As the input voltage is dropped below 12Vac using any of the standard dimming methods described in the Background section above, the voltage presented to GP 0 of U 5 will correspondingly lower. The microcontroller is programmed to monitor this input and execute a dimming algorithm based on the sampled input voltage level.
In this implementation, the dimming algorithm has been set to begin dimming when GP 0 drops below 3V, and dim linearly to off when GP 0 drops to 50% (1.5V). At 50%, there is still sufficient voltage on the 12VDC line to reliably power the microcontroller U 5 and the MCP1650V U 6 . Thus, a stable linear dimming output is achieved which is consistent from LED lamp to LED lamp, and eliminates the low-end dimming problems of prior-art LED drivers when used in retrofit lamp applications as explained in the Background section above.
The output dimming in this implementation is achieved through manipulation of the VREF reference voltage presented to the internal error amplifier of the MCP1630V U 6 . As explained above, when the GP 5 output of U 5 is set high, the VREF input of U 6 will be 196 mV, and the output current will regulate at 350 mA which has been chosen to be the maximum (no dimming) current output through the LEDS. With GP 5 low, VREF will be 0V, and no current will be output to the LEDs. Under software control, the microcontroller preferably pulses this output in a PFM fashion to cause the LED current to alternate between 0 and 350 mA at a rate that is undetectable to the human eye, and which results in a dimmed illumination level proportional to the PFM duty cycle. As noted above, the output pulses of U 5 GP 5 need not be PFM. Any other digital modulation technique or a combination of several can be used with equal effectiveness, and should be considered as within the scope of the present invention.
It should also be noted that the value of capacitor C 8 in FIG. 10 can be chosen to filter out the GP 5 pulses, and integrate them into an analog voltage level so that the LED current reduces in absolute value, rather than pulsed between maximum and minimum levels. Thus, the pulse integration occurs at the circuitry level rather than with the human eye. Additionally, a microcontroller can be chosen for U 5 which has an onboard digital-to-analog converter (DAC), so that an analog output voltage is presented to VREF, rather than digital pulses. Or, analog voltages could be provided to VREF by an external DAC which is controlled by the microcontroller U 5 . All of these methods will be recognized by one skilled in the art as within the scope of the present invention.
Because the microcontroller U 5 has complete control over the LED current through its control of the MCP1630V U 6 , alternate and complex dimming algorithms can be achieved in response to sampled changes in the input voltage. The dimming algorithm discussed above is linear from 350 mA LED current at 12Vac input to 0 LED current at 6Vac input. It may be desirable to have a non-linear response where greater dimming occurs in response to changes in the upper input voltage ranges and less in response to changes at lower ranges to compensate for the greater sensitivity of the human eye at lower light levels. Or, it may be desirable to have the LED lamp mimic the dimming curve seen by a halogen lamp in a fixture in close proximity to the LED lamp.
The present invention provides far greater control over the dimming of an LED lamp than has previously been capable in retrofit or other applications where there is no separate external dimming control signal. It allows for custom and tuned dimming response in systems employing standard AC or DC dimmers which only affect changes in the input voltage to the lamp.
|
A driver circuit produces variable current output for an LED lighting system providing improved dimming capability and greater power efficiency when responding to industry standard lighting dimmers, through the use of an input voltage monitoring circuit which variably controls the current output of a switching regulator. Output current modulation methods such as analog, PWM, Pulse Frequency Modulation, or other digital modulation, and combination or hybrid methods may be employed. The current invention marries such output modulation techniques with a control method which is derived through intelligent monitoring of the input voltage waveform. The circuit and method described is adapted to higher current applications such as LED lighting systems using the latest high-power LEDs.
| 7
|
BACKGROUND OF THE INVENTION
There is need for electric switches of small size for both consumer appliance applications, and in low voltage-low current electronic apparatus. For consumer appliances, such switches must be capable of relatively high electrical ratings, while their use in electronic applications often requires satisfactory operation and circuit completion under, or near, "dry circuit" conditions. Competitive market conditions require that such switches be economical to manufacture, and that they avoid use of expensive contact materials.
OBJECTS OF THE INVENTION
It is a primary object of the present invention to provide an improved snap-action switch which is economical to manufacture, capable of high electrical ratings, and also useable in low voltage-low current applications, and
A further more specific object is to provide a novel form of snap-action mechanism which is characterized by affording contact wiping action in circuit breaking operation, and abutting contact making operation.
Other objects and advantages of the invention will hereinafter appear.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view in side elevation of an electric switch constructed in accordance with the invention;
FIG. 2 is a view in longitudinal cross section, to enlarged scale, of the switch of FIG. 1;
FIG. 3 is a view in transverse cross section taken along the line 3--3 of FIG. 2;
FIG. 4 is a view taken along the line 4--4 of FIG. 2;
FIG. 5 is an exploded isometric view of parts of the movable contactor used in the switch, and
FIG. 6 is a fragmentary view of a modified form of switch incorporating the invention shown in FIGS. 1 to 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The switch of the present invention generally comprises main base 10, combined cover and bushing member 12, frame 14, external paddle type lever 16, and contact terminals 18, 20 and 22.
Base 10 is provided with an enlarged internal cavity in which are mounted the contact portions of contact terminals 18, 20 and 22, a contactor 24, a contactor actuator member 26, a helical compression spring 28, and the contactor operating portion 16b of lever 16. The contact portions of the contact terminals 18, 20 and 22 are each of the bifurcated or U-shaped form in transverse section as shown for contact terminal 20 in FIG. 3.
Upwardly depending contact portions 20a and 20b of terminal 20 fit within vertical channels 10a formed between pairs of inwardly extending bosses 10b which are formed on the opposite inner side walls of the base cavity. The bosses 10b are generally rectangular in cross section and terminal below the upper end of the base. The cover and bushing member 12 seat on the upper ends of the bosses 10b, and seat against the upper ends of the contact portions 20a and 20b in recesses 12a which are spaced apart on opposite sides of the bushing portion 12b. The contact portions 20a and 20b integrally join with a terminal portion 20c which extends through a closely fitting rectangular opening formed in the bottom of the base 10.
Contact terminals 18 and 22 as aforedescribed are provided with bifurcated or U-shaped contact portions like the portions 20a and 20b of contact terminal 20 and the upper ends of these portions fit within pairs of recesses 12c and 12d respectively found adjacent the longitudinal margins of the member 12. Members 18 and 22 near the bights thereof abut on opposite sides of boss portions 10c which extend centrally upwardly from the inner bottom wall of base 10. Such members then extend at a right angle towards the opposite end walls with the bar cavity and then at a right angle through closely fitting rectangular openings formed in the bottom wall of base 10.
As best shown in FIGS. 2 and 3, compression spring 28 seats as its lower end within a frusto-conical recess 10d formed in the boss portion 10c of base 10 and astride a restraining nib 20d which is integrally formed on the bight of contact terminal 20. At its upper end spring 28 seats against a downwardly extending hollow frusto conical boss portion 24a of the contactor 24. As best shown in FIG. 5, contactor 24 is integrally formed, preferably of a good electrical conducting metal such as brass, and is symmetrical about its generally square central portion 24b. Arm portions 24c angle downwardly and then laterally outwardly and merge at their ends with contact portions 24d which extend upwardly at a right angle therefrom.
The contact portions 24d are of a width greater than the distance between the bifurcated contact portion of the contact terminal 18, 20 and 22, and as will hereinafter be more fully explained, are adapted to abut against both the contact portions of each pair of contact portions of the members 18 and 22. The central portion 24b and arms 24c of contactor 24 are relatively narrow in relation to the spaces between the bifurcated contact portions of members 18, 20 and 22 to insure good electrical clearance.
Contact actuator 26 is of the form best shown in FIG. 5, and is preferably formed of resilient, berylium-copper metal. The central portion 26a is of inverted V-shape and overlies in spaced apart relation the central portion 24b of actuator 24. Such portion 26a engages with the downwardly extending portions of the arms 24c and merges with arm portions 26b which overlie the outwardly extending part of arm portions 24c of member 24. The arm portions 26b at their respective ends turn upwardly at a right angle and abut against the insides of the contact portions 24d. At opposite sides of the central portion 26a are outwardly and downwardly extending flexible contact portions 26d which engage with the insides of the contact portions 20a and 20b of contact terminal 20 as best shown in FIG. 3.
As best shown in FIGS. 2 and 3, the actuating lever 16 has a paddle lever 16a which is integrally joined with a main body portion 16c which is of a semicylindrical shape with depending sides 16d and 16e. The sides 16d and 16e have aligned circular apertures 16f which accommodate and pivot about complementally formed trunnion portions 12e which extend outwardly from opposite sides of the bushing portion 12b of member 12. The actuator lever portion 16b extends downwardly centrally between the sides 16d and 16e and engages at a lower hemispherical end 16g with the upper surface contactor actuator 26.
The frame comprises a top portion 14a which overlies the cover and bushing member 12 and the upper end of base 10. A central aperture 14b is provided to accommodate the bushing portion 12b and upstanding short cylindrical bosses 14c on opposite sides of bushing portion are provided for a purpose hereinafter described. Frame 14 has end portions 14d which extend downwardly at a right angle from the portion 14a and abut tightly against the end walls of the base 10. Pairs of spaced apart mounting tangs 14e extend downwardly from each of the lower extremeties of the portions 14d for a purpose to later be described. The frame 14 also has four assembly fastening and securing tabs 14f which extend down along the sides of base 10 adjacent the corners thereof. The tabs 14f adjacent their lower ends are bent inwardly and clinched into recesses 10f formed in the outer surface of base 10. It will be seen that the aforedescribed formation and arrangement of the frame 14 provides for holding and maintaining all of the parts in the switch cavity, the bushing and cover member 12 and base 10 in assembled relation.
As shown in FIG. 2 the switch is in its operating position in which electrical circuit is completed and maintained between center or common contact terminal 20 and contact terminal 22. In this position the contact portion 26d of contactor actuator 26 are outwardly biased into engagement with the inner side surfaces of contact portions 20a and 20b, while the inner surface of the right hand contact portion 24d of contactor 24 engages with the right hand most surface of the bifurcated vertical contact portions of contact terminal 22.
Now let it be assumed that the lever 16a of actuating lever 16 is pivoted clockwise as viewed in FIG. 2. The end 16g then moves to the left, engages with and cams the inverted V-shaped portion 26a of member 26. This causes the latter and contactor 24 to simultaneously pivot clockwise and move downwardly and compress spring 28. With such cammed movement of actuator 26 and contactor 24, the right hand portion 24d of the latter slides with wiping action on the right hand surfaces of the contact portion of contact terminal 22, and the portions 26d of the actuator slide on the inner surface of contact portions 20a and 20b.
The above mentioned cammed movement continues until the end 16g of the actuator engages the apex of the central portion 26a of the actuator. When the end 16g moves over and beyond the apex, stored energy in spring 28 causes snap-action upward and longitudinal movement of members 24 and 26, thereby moving the right hand contact portion 24d out of engagement with the contact portion of terminal 22, and effecting abutting engagement of the left hand contact portion 24d with the contact portions of terminal 18. During such snap-action movement, the portions 26d of the actuator slide on the contact portion 20a and 20b of terminal 20.
When lever 16 is moved from its last mentioned right hand position back to its position of FIG. 2, similar movement of actuator 26 and contactor 24 will occur as the actuator and its inverted V-shaped surface are symmetrical about its center point. It will be apparent that the aforementioned sliding, wiping action of contactor 24 on the contact portions of terminals 18 and 22 will afford positive breaking of tack welds that can occur because or arcing under high current conditions, and also promotes cleaning of oxides that build up under low voltage-low current operating conditions.
As will be noted the mounting tangs 14e and terminal portions of contact terminals 18, 20 and 22 are of a size and shape permitting their insertion through openings on printed circuit boards so that they may be secured thereto and circuit connections made thereon by soldering. However, the switches of this invention are not limited to the exterior terminal configuration and mounting arrangements depicted, and it will be apparent that other exterior terminal forms can be readily adapted.
FIG. 6 shows a modification of the switch of FIGS. 1 to 5, in which a coil compression spring 30 is disposed about and seats at its lower end about the right hand boss 14c on frame 14, and seats at its upper end against a hemispherical boss 16h formed on the lower surface of lever 16. When lever 16 is pivoted clockwise to provide the circuit interrupting and completing operations above described in connection with FIG. 2, spring 30 will be compressed. If lever 16 is then released the energy stored in the compressed spring 30 will cause lever 16 to pivot counter clockwise and restore the contactor 24 and actuator 26 to their positions shown in FIG. 2. This modified switch version of FIG. 6 provides a maintained circuit condition between contact terminals 20 and 22 and a momentary type circuit between contact terminal 18 and 20 whereas the version of FIGS. 1 to 5 provides maintained circuits in both operating positions of lever 16.
|
An electric snap-action electric switch is disclosed which employs movable contact means having an inverted V-shaped cam surface. The movable contact means is spring biased into engagement along its cam surface with the end of a pivoted operator lever. Upon movement from one extreme position the lever cams and pivots the contact means inwardly of the switch until the end of the lever rides beyond the apex of the V-shaped surface, whereupon the contact means moves with snap action under spring action to change switch circuits. Contact wiping action occurs during inward pivotal movement of said contact means, and abutting stationary contact engagement results from its snap-action movement.
| 7
|
[0001] This application is a divisional of U.S. patent application Ser. No. 11/335,916, filed Jan. 18, 2006, which claims priority to U.S. patent application Ser. No. 10/622,130, filed Jul. 16, 2003, which claims priority to 60/397,367, filed Jul. 18, 2002, the contents of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates to heteroatom-containing diamondoids (i.e., “heterodiamondoids”) which are compounds having a diamondoid nucleus in which one or more of the diamondoid nucleus carbons has been substitutionally replaced with a noncarbon such as a group IIIB, noncarbon group IVB, group VB or VIB atom. (Groups are based on the previous IUPAC Periodic Table groups as referenced in Hawley's Condensed Chemical Dictionary, 14 th ed. John Wiley & Sons, Inc, 2001.) These heteroatom substituents impart desirable properties to the diamondoid. In addition, the heterodiamondoids can be functionalized affording compounds carrying one or more functionalization groups covalently pendant therefrom. Functionalized heterodiamondoids having polymerizable functional groups are able to form polymers containing heterodiamondoids.
[0003] In a preferred aspect the diamondoid nuclei are triamantane and higher diamondoid nuclei. In another preferred aspect, the heteroatoms are selected to give rise to diamondoid materials which can serve as n- and p-type materials in electronic devices.
BACKGROUND INFORMATION
[0004] Diamondoids are cage-shaped hydrocarbon molecules possessing rigid structures which are tiny fragments of a diamond crystal lattice. Adamantane is the smallest member of the diamondoid series and consists of a single cage structure of the diamond crystal lattice. Diamantane contains two adamantane subunits face-fused to each other, triamantane three, tetramantane four, and so on. While there is only one isomeric form of adamantane, diamantane and triamantane, there are four different isomeric tetramantanes (i.e., four different shapes containing four adamantane subunits). Two of the isomeric tetramantanes are enantiomeric. The number of possible isomers increases rapidly with each higher member of the diamondoid series.
[0005] Adamantane, which is commercially available, has been functionalized. For instance, U.S. Pat. No. 3,832,332 describes a polyamide polymer formed from alkyladamantane diamine; U.S. Pat. No. 5,017,734 discusses the formation of thermally stable resins from ethynyl adamantane derivatives; and, U.S. Pat. No. 6,235,851 reports the synthesis and polymerization of a variety of adamantane derivatives.
[0006] The following references related to adamantane and derivatives formed from adamantane:
Capaldi, et al., Alkenyl Adamantanes, U.S. Pat. No. 3,457,318, issued Jul. 22, 1969 Thompson, Polyamide Polymer of Diamino Methyl Adamantane and Dicarboxylic Acid, U.S. Pat. No. 3,832,332, issued Aug. 27, 1974 Baum, et al., Ethynyl Adamantane Derivatives and Methods of Polymerization Thereof U.S. Pat. No. 5,017,734, issued May 21, 1991 Ishii, et al., Polymerizable Adamantane Derivatives and Process for Producing Same, U.S. Pat. No. 6,235,851, issued May 22, 2001 McKervey, et al., Synthetic Approaches to Large Diamondoid Hydrocarbons, Tetrahedron 36, 971-992 (1980) Lin, et al., Natural Occurrence of Tetramantane ( C 22 H 28 ), Pentamantane ( C 26 H 32 ) and Hexamantane ( C 30 H 36 ) in a Deep Petroleum Reservoir, Fuel 74:10, 1512-1521 (1995) Chen, et al., Isolation of High Purity Diamondoid Fractions and Components, U.S. Pat. No. 5,414,189, issued May 9, 1995 Balaban et al., Systematic Classification and Nomenclature of Diamond Hydrocarbons -1, Tetrahedron 34, 3599-3606 (1978) Gerzon et al., The Adamantyl Group in Medicinal Agents, 1. Hypoglycemic N- Arylsulfonyl - N - adamantylureas, Journal of Medicinal Chemistry 6 (6), 760-763 (November 1963) Marshall et al., Further Studies on N - Arylsulfonyl - N - alkylureas, Journal of Medicinal Chemistry 6, 60-63 (January 1963) Marshall et al., N - Arylsulfonyl - N - alkylureas, Journal of Organic Chemistry 23, 927-929 (June 1958) Reinhardt, Biadamantane and Some of its Derivatives, Journal of Organic Chemistry 27, 3258-3261, (September 1962) Sasaki et al., Synthesis of Adamantane Derivatives. II. Preparation of Some Derivatives from Adamantylacetic Acid, Bulletin of the Chemical Society of Japan 41:1, 238-240 (June 1968) Stetter et al, Ein Beitrag zur Frage der Reaktivitat von Bruckenkopf - Carboniumionen, Uber Verbindungen mit Urotropin - Struktur, XXVI, Chem. Ber. 96 550-555, (1963) Hass et al, Adamantyloxycarbonyl, a New Blocking Group. Preparation of 1- Adamantyl Chloroformate, Journal of the American Chemical Society 88:9, 1988-1992 (May 5, 1966) Stetter et al, Neue Moglichkeiten der Direktsubstitution am Adamantan, Uber Verbindungen mit Urotropin - Struktur, XLIII, Chem. Ber. 102 (10), 3357-3363 (1969) von H. U. Daeniker, 206. 1- Hydrazinoadamantan, Helvetica Chimica Acta 50, 2008-2010 (1967) Stetter et al, Uber Adamantan - phosphonsaure -(1)- dichlorid, Uber Verbindungen mit Urotropin - Struktur, XLIV, Chem. Ber. 102 (10), 3364-3366 (1969) Lansbury et al, Some Reactions of ∀ - Metalated Ethers, The Journal of Organic Chemistry 27:6, 1933-1939 (Jun. 12, 1962) Stetter et al, Herstellung von Derivaten des 1- Phenyl - adamantans, Uber Verbindungen mit Urotropin - Struktur, XXXI, Chem. Ber. 97 (12), 3488-3492 (1964) Nordlander et al, Solvolysis of 1- Adamantylcarbinyl and 3- Homoadamantyl Derivatives. Mechanism of the Neopentyl Cation Rearrangement, Journal of the American Chemical Society 88:19 (Oct. 5, 1966) Sasaki et al, Substitution Reaction of 1- Bromoadamantane in Dimethyl Sulfoxide: Simple Synthesis of 1- Azidoadamantane, Journal of the American Chemical Society 92:24 (Dec. 2, 1970) Chakrabarti et al, Chemistry of Adamantane. Part II. Synthesis of 1- Adamantyloxyalkylamines, Tetrahedron Letters 60, 6249-6252 (1968) Stetter et al, Derivate des 1- Amino - adamantans, Uber Verbindungen mit Urotropin - Struktur, XXIV, Chem. Ber. 95, 2302-2304 (1962) Stetter et al, Zur Kenntnis der Adamantan - carbonsaure, Uber Verbindungen mit Urotropin - Struktur, XVII, Chem. Ber. 93, 1161-1166 (1960) Makarova et al, Psychotropic Activity of Some Aminoketones Belonging to the Adamantane Group, Pharmaceutical Chemistry Journal, 34:6 (2000)
[0033] As noted above, heterodiamondoids are those diamondoids in which at least one cage carbon atom is replaced by a heteroatom. The following references describe more details about heteroadamantanes and heterodiamantanes.
Meeuwissen et al, Synthesis of 1- Phosphaadamantane, Tetrahedron Letters, 39:24, 4225-4228 (1983) Boudjouk et al, The Reaction of Magnesium with cis -1,3,5- Trsi ( bromomethyl ) cyclohexane. Evidence For a Soluble Tri - grignard, Journal of Organometallic Chemistry 281, C21-C23 (1985) Boudjouk et al, Synthesis and Reactivity of 1- Silaadamantyl Systems, Journal of Organometallic Chemistry 2, 336-343 (1983). Krishnamurthy et al, Heteroadamantanes. 2 . Synthesis of 3- Heterodiamantanes, Journal of Organometallic Chemistry, 46:7, 1389-1390 (1981) Udding et al, A Ring - opening Reaction of and Some Cyclisations to the Adamantane System. A Quasi - favorsky Reaction of a ∃ - bromoketone, Tetrahedron Letters 55, 5719-5722 (1968) Blaney et al, Chemistry of Diamantane, Part II. Synthesis of 3,5- disubstituted Derivatives, Synthetic Communications 3:6, 435-439 (1973) Henkel et al, Neighboring Group Effects in the ∃ - halo Amines. Synthesis and Solvolytic Reactivity of the anti -4- Substituted 2-Azaadamantyl System, Journal of Organometallic Chemistry 46, 4953-4959 (1981) Becker et al, A Short Synthese of 1- azaadamantan -4- one and the 4 r and 4 s Isomers of 4- Amino -1- azaadamantane, Synthesis, (11), 1080-1082 (1992) Eguchi et al, A Novel Route to the 2- Aza - adamantyl System via Photochemical Ring Contraction of Epoxy 4- Azahomoadamantanes, Journal of Organometallic Chemistry, Commun., 1147-1148 (1984) Gagneux et al, 1- Substituted 2- Heteroadamantanes, Tetrahedron Letters 17, 1365-1368 (1969) Bubnov et al, A Novel Method of Synthesis of 1- azaadamantane from 1- boraadamantane, Journal of Organometallic Chemistry 412, 1-8 (1991). Sasaki et al, Synthesis of Adamantane Derivatives. 39. Synthesis and Acidolysis of 2- Azidoadamantanes. A Facile Route to 4- Azahomoadamant -4- enes, Heterocycles 7:1 315-320 (1977) Sasaki et al, Synthesis of Adamantane Derivatives. 47. Photochemical Synthesis of 4- Azahomoadamant -4- enes and Further Studies on Their Reactivity in Some Cycloadditions, Journal of Organometallic Chemistry, 44:21, 3711-3712 (1979) German Patent No. DE 2,545,292 issued April, 1979 Suginome et al, Photoinduced Transformations. 73 . Transformations of Five -( and Six -) Membered Cyclic Alcohols into Five -( and Six -) Membered Cyclic Ethers - A New Method of a Two - Step Transformation of Hydroxy Steroids into Oxasteroids, Journal of Organometallic Chemistry 49, 3753-3762, (1984)
[0049] Adamantane and substituted adamantane are the only readily available diamondoids. Diamantane and triamantane and substituted diamantanes have been studied, and only a single tetramantane has been synthesized. The remaining diamondoids were provided for the first time by the inventors Dahl and Carlson, and are described for example, in U.S. Patent Application Ser. No. 60/262,842 filed Jan. 19, 2001 and PCT US02/00505 filed 17 Jan. 2002.
SUMMARY OF THE INVENTION
[0050] The invention provides heterotriamantanes and hetero higher diamondoids. Heteroatoms are selected from atoms of group IIIB elements such as B or A1; noncarbon group IV B elements such as Si; group V B elements such as N, P or As, and particularly N or P; and group VI B elements such as O, S, or Se. It will be noted that the group VB elements are generally classed as electron-donating (hole-accepting) or “electropositive” atoms and the group III B elements are generally classed as electron-accepting (hole-donating) or “electronegative” atoms.
[0051] These heterodiamondoids of the invention are a triamantane or a higher diamondoid nucleus with 1 or more (for example 1 to 20 and especially 1 to 6) of its cage carbons replaced by a heteroatom. The heterodiamondoids can also be substituted with up to 6 alkyl groups per diamondoid unit.
[0052] This invention is further directed to functionalized heterodiamondoids. In this embodiment the heterotriamantanes and higher heterodiamondoids contain at least 1 and, preferably 1 to 6 functional group(s) covalently bonded to cage carbons, presented as Formula I:
[0000]
[0000] wherein, G is a heterotriamantane or a higher heterodiamondoid nucleus with one or more heteroatoms as described; and, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are each independently selected from a group consisting of hydrogen and covalently bonded functional groups, provided that there is at least 1 functional group. More preferably, the functionalized heterodiamondoids contain either 1 or 2 functional groups and from 1 to 6 heteroatoms.
[0053] These heterodiamondoids and functionalized heterodiamondoids can exist as discrete individual molecules. They can also exist as crystalline aggregates. These crystalline structures can be pure heterodiamondoids or pure functionalized heterodiamondoids or can, intentionally or inadvertendly, be a mixture of more than one diamondoid with or without functionalization, with heterodiamondoid and/or functionalized heterodiamondoid.
[0054] Some of these functionalized heterodiamondoids can be prepared from heterodiamondoids in a single reaction step. These materials are referred to herein as “primary functionalized heterodiamondoids” and include, for example, heterodiamondoids of Formula I wherein the functionalizing groups are halogens (such as -bromos, and chloros), -thios, -oxides, -hydroxyls, and -nitros, as well as other derivatives formed in one reaction from a heterotriamantane or a higher heterodiamondoid.
[0055] Others of these functionalized heterodiamondoids are materials prepared from a primary functionalized heterodiamondoids by one or more subsequent reaction steps. These materials are referred to herein as “secondary functionalized heterodiamondoids.” It will be appreciated that in some cases one primary functionalized heterodiamondoid may be conveniently formed by conversion of another “primary” material. For example, a poly-bromo material can be formed either by single step bromination or by several repeated brominations. Similarly, a hydroxyl heterodiamondoid can be formed directly from a heterodiamondoid in one step or can be prepared by reaction of a bromo-heterodiamondoid, a diamondoid-oxide or the like. Notwithstanding this, to avoid confusion, the “primary” materials will not be included here in the representative secondary materials. They will, however, be depicted in various figures showing reactions for forming primary and secondary materials to depict both routes to them.
[0056] Representative “secondary functionalized heterodiamondoid” functional groups include haloalkyl, haloalkenyl, haloalkynyl, hydroxyalkyl, heteroaryl, alkylthio, alkoxy; aminoalkyl, aminoalkoxy, heterocycloalkoxy, cycloalkyloxy, aryloxy, and heteroaryloxy.
[0057] Other functional groups that can be present in the secondary functionalized heterodiamondoids are represented by the formula —C(O)Z wherein Z is hydrogen, alkyl, halo, haloalkyl, halothio, amino, monosubstituted amino, disubstituted amino, cycloalkyl, aryl, heteroaryl, heterocyclic; —CO 2 Z wherein Z is as defined previously; —R 7 COZ and —R 7 CO 2 Z wherein R 7 is alkenyl aminoalkenyl, or haloalkenyl and Z is as defined previously; —NH 2 ; —NHR′, —NR′R″, —N + R′R″R′″ wherein R′, R″, and R′″ are independently alkyl, amino, thio, thioalkyl, heteroalkyl, aryl, or heteroaryl; —R 8 NHCOR 9 wherein R 8 is —CH 2 —, —OCH 2 —, —NHCH 2 —, —CH 2 CH 2 —, —OCH 2 CH 2 — and R 9 is alkyl, aryl, heteroaryl, aralkyl, or heteroaralkyl; and —R 10 CONHR 11 — wherein R 10 is selected from —CH 2 —, —OCH 2 —, —NHCH 2 —, —CH 2 CH 2 —, and —OCH 2 CH 2 —, and R 11 is selected from hydrogen, alkyl, aryl, heteroaryl, aralkyl, and heteroaralkyl.
[0058] In a further preferred embodiment, the functional group on the functionalized heterodiamondoid is —COOR 16 wherein R 16 is alkyl, aryl, or aralkyl; —COR 17 , wherein R 17 is alkyl, aryl, or heteroalkyl; —NHNH 2 ; —R 18 NHCOR 19 wherein R 18 is absent or selected from alkylene, arylene, or aralkylene, R 19 is hydrogen, alkyl, —N 2 , aryl, amino, or —NHR 20 wherein R 20 is hydrogen, —SO 2 -aryl, —SO 2 -alkyl, SO 2 aralkyl or —CONHR 21 wherein R 21 is hydrogen, alkyl, aralkyl, or —CSNHR 21 wherein R 21 is as defined above; and —NR 22 —(CH 2 ) n —NR 23 R 24 , wherein R 22 , R 23 , R 24 are independently selected from hydrogen, alkyl, and aryl, and n is from 1 to 20.
[0059] In an additional embodiment, the functional group on the functionalized heterodiamondoid may be independently selected from —N═C═S; —N═C═O; —R—N═C═O; —R—N═C═S; —N═S═O; R—N═S═O wherein R is alkyl; —PH 2 ; —POX 2 wherein X is halo; —PO(OH) 2 ; halo; —OSO 3 H; —SO 2 H; —SOX wherein X is halo; —SO 2 R wherein R is alkyl; —SO 2 OR wherein R is alkyl; —SONR 26 R 27 wherein R 26 and R 27 are independently hydrogen or alkyl; —N 3 ; —OC(O)Cl; or OC(O)SCl.
[0060] In further an additional embodiment, one or more of the functional groups on the functionalized heterodiamondoids may be of the formula:
[0000]
[0000] wherein n is 2 or 3; X is oxygen, sulfur, or carbonyl; Y is oxygen or sulfur; and R 8 is selected from the group consisting of hydrogen, alkyl, heteroalkyl, aryl, and heteroaryl.
[0061] In a further aspect, the functionalizing group may form a covalent bond to two or more of these heterodiamondoids and thus serve as a linking group or polymerizable group between the two or more heterodiamondoids. This provides functionalized heterodiamondoids of formula II:
[0000] G-L-(G) n or G-L-(D) n or G-(L-G) n or G-(L-D) n or (G-L) n or the like II
[0000] wherein D is a diamondoid nucleus, G is a heterotriamantane or a higher heterodiamondoid nucleus and L is a linking group and n is 1 or more such as 2 to 1000 and especially 2 to 500.
[0062] In this embodiment, the linking group L may be, for example, aryls, alkenyls, alkynyls, esters, amides, —N═C—N—;
[0000]
[0000] wherein R 28 , R 29 , R 30 , R 31 , R 32 , R 33 are independently hydrogen or alkyl, and n and m are independently from 2 to 20;
[0000]
[0000] wherein R 28 , R 29 , R 30 , R 31 , R 32 , and R 33 are hydrogen or alkyl; R 34 , R 35 , R 36 , and R 37 are independently absent or hydrogen or alkyl with the proviso that at least one of R 34 , R 35 , R 36 , and R 37 is present; and n and m are independently from 2 to 20 or the like.
[0063] In another aspect, the present invention relates to functionalized heterodiamondoids of formula III:
[0000] (R′) n -G-G′-(R″) m III
[0000] wherein G and G′ are each independently a heterodiamondoid nucleus and R′ and R″ are substituents on the heterodiamondoid nucleus and are independently hydrogen or a functionalizing group. n and m are 1 or more such as 1 to 10 and preferably 1 to 6. More preferably the material contains either 1 or 2 functional groups. Preferably R′ and R″ are halo; cyano; aryl; arylalkoxy; aminoalkyl; or —COOR 40 wherein R 40 is hydrogen or alkyl.
[0064] The heterodiamondoids and functionalized heterodiamondoids of the present invention are useful in for instance, nanotechnology, drugs, drug carriers, pharmaceutical compositions, precursors for the synthesis of biologically active compounds, photoresist materials and/or photoresist compositions for far UV lithography, synthetic lubricants, heat resist materials and solvent-resistant resins, and so on. For example, these heterodiamondoid derivatives may have desirable lipophilic properties, which may improve the bioavailability of pharmaceutically active groups attached thereto. These heterodiamondoids and derivatives may also be useful as chemical intermediates for the synthesis of further functionalized heterodiamondoids to form a variety of useful materials. Such materials include composite matrix resins, structural adhesives and surface files that are used for aerospace structural applications. Furthermore, coating layers or molded products with excellent optical, electrical or electronic and mechanical properties are produced for use in optical fibers, photoresist compositions, conduction materials, paint compositions and printing inks. In addition, these heterodiamondoid derivative-containing materials will have high thermal stability making them suitable for use in environments requiring such stability including for example, devices such as semiconductors, coatings for refractory troughs or other high temperature applications.
[0065] In applications of particular importance, the heteroatoms introduced into the triamantane of higher diamondoid nucleus are electron-donating or electron-accepting. The semiconducting heterodiamondoids that result have utility in a variety of transistor and other electronic and microelectronic settings.
[0066] In addition, when the heteroatoms in the heterodiamondoids are electron-donating, and particularly nitrogen, this gives rise to the possibility that the donated electrons can be excited from the normal valence bond through a bond gap into a conductive bond. When the excited electrons decay back to their base state, particularly if a vacancy is adjacent to the electron-donating heteroatom, a photon can be emitted. This suggests that these hetrodiamondoids could have properties to provide molecular size and crystallite-sized flouresent species, lasing species and photodetecting species. (See Kurtsiefer, C, et al Stable Solid - State Source of Single Photons, Physical Review Letters 85, 2, 290-293 (2000).
BRIEF DESCRIPTION OF THE DRAWINGS
[0067] This invention will be further described with reference to the drawings in which:
[0068] FIG. 1 shows the numbering of four tetramantanes and points out representative secondary, tertiary and quaternary carbon atoms.
[0069] FIG. 2 presents exemplary computer modeling calculations that illustrate the feasibility of the synthesis of heterodiamondoids.
[0070] FIGS. 3-5 illustrate reaction routes for introducing an oxygen heteroatom into a diamondoid.
[0071] FIG. 6 illustrates routes for introducing a sulfur heteroatom into a diamondoid.
[0072] FIGS. 7-8 illustrate routes for introducing a nitrogen heteroatom into a diamondoid.
[0073] FIGS. 9-23 illustrate representative routes for functionalizing heterodiamondoids.
[0074] FIGS. 24-33 illustrate representative polymers containing heterodiamondoids and routes to prepare them.
[0075] FIG. 34 shows the total ion chromatogram (TIC) of the photohydroxylated mixture of Example 2 containing hydroxylated tetramantanes including hydroxylated alkyl tetramantanes.
[0076] FIG. 35 is the m/z 308 ion chromatogram showing the presence of monohydroxylated tetramantanes in the TIC of the reaction mixture of Example 2.
[0077] FIG. 36 is the mass spectrum of a monohydroxylated tetramantane with GC/MS retention time of 19.438 minutes from FIG. 35 . The base peak in this spectrum is the m/z 308 molecular ion.
[0078] FIG. 37 is the m/z 322 ion chromatogram showing the presence of monohydroxylated methyltetramantanes in the TIC of the reaction product of Example 2.
[0079] FIG. 38 is the mass spectrum of monohydroxylated methyltetramantane from FIG. 37 with GC/MS retention times of 19.998 minutes.
[0080] FIG. 39 shows the total ion chromatogram (TIC) of the oxa tetramantane-containing reaction mixture also produced in Example 2.
[0081] FIG. 40 is the m/z 294 ion chromatogram showing the presence of oxa tetramantanes in the TIC of the reaction product of Example 2.
[0082] FIG. 41 is the mass spectrum of an oxa tetramantane with GC/MS retention time of 17.183 minutes from FIG. 40 .
[0083] FIG. 42 shows the total ion chromatogram (TIC) of the azahomo tetramantane-ene-containing reaction mixture of Example 3.
[0084] FIG. 43 is the m/z 305 ion chromatogram showing the presence of azahomo tetramantane-enes in the TIC of the reaction mixture of Example 3.
[0085] FIG. 44 is the mass spectrum of an azahomo tetramantane-ene with GC/MS retention time of 18.062 minutes from FIG. 43 .
[0086] FIG. 45 is the m/z 319 ion chromatogram showing the presence of azahomo methyltetramantane-enes in the TIC of the reaction product.
[0087] FIG. 46 is the mass spectrum of an azahomo methyltetramantane-ene with GC/MS retention time of 18.914 minutes from FIG. 45 .
[0088] FIG. 47 shows the total ion chromatogram (TIC) of the epoxy azahomo tetramantane-containing reaction mixture produced in Example 3.
[0089] FIG. 48 is the m/z 321 ion chromatogram showing the presence of epoxy azahomo tetramantanes in the TIC of the reaction product of Example 3.
[0090] FIG. 49 is the mass spectra of an epoxy azahomo tetramantane with GC/MS retention times of 21.929 from FIG. 48 .
[0091] FIG. 50 is the m/z 335 ion chromatogram showing the presence of epoxy azahomo methyltetramantanes in the TIC of a reaction product of Example 3.
[0092] FIG. 51 is the mass spectrum of an epoxy azahomo methyltetramantane with GC/MS retention time of 21.865 minutes from FIG. 50 .
[0093] FIG. 52 shows the total ion chromatogram (TIC) of the N-formyl aza tetramantane-containing reaction mixture of Example 3.
[0094] FIG. 53 is the m/z 321 ion chromatogram showing the presence of N-formyl aza tetramantanes in the TIC of the reaction product of Example 3.
[0095] FIG. 54 is the mass spectrum of a N-formyl aza tetramantanes with GC/MS retention time of 21.826 minutes from FIG. 53 .
[0096] FIG. 55 is the m/z 335 ion chromatogram showing the presence of the N-formyl aza methyltetramantanes in the TIC of a reaction product of Example 3.
[0097] FIG. 56 is the mass spectrum of a N-formyl aza methyltetramantane with GC/MS retention time of 21.746 minutes from FIG. 55 .
[0098] FIG. 57 shows the total ion chromatogram (TIC) of the aza tetramantane-containing reaction mixture produced in Example 3.
[0099] FIG. 58 is the m/z 293 ion chromatogram showing the presence of the aza tetramantanes in the TIC of the reaction product shown in Example 3.
[0100] FIG. 59 is the mass spectrum of an aza tetramantane with GC/MS retention time of 19.044 minutes.
[0101] FIG. 60 is the m/z 307 ion chromatogram showing the presence of the aza methyltetramantanes in the TIC of a reaction product of Example 3.
[0102] FIG. 61 is the mass spectrum of an aza methyltetramantane with GC/MS retention time of 22.936 minutes.
[0103] FIG. 62 is the m/z 321 ion chromatogram showing the presence of the aza dimethyltetramantanes in the TIC of a reaction product of Example 3.
[0104] FIG. 63 is the mass spectrum of an aza dimethyltetramantane with GC/MS retention time of 22.742 minutes from FIG. 62 .
DETAILED DESCRIPTION OF THE INVENTION
[0105] This detailed description is presented in the following subsections:
DEFINITIONS
Synthesis of Heterodiamondoids
[0106] Functionalization of Heterodiamondoids and Derivatives Therefrom
[0107] Heterodiamondoid-Containing Polymers
Definitions
[0108] As used herein, the following terms have the following meanings.
[0109] The term “diamondoid” is given a special meaning. It refers to substituted and unsubstituted caged compounds of the adamantane series beginning with triamantane and including, in addition, tetramantane, pentamantane, hexamantane, heptamantane, octamantane, nonamantane, decamantane, undecamantane and dodecamantane. A higher diamondoid is tetramantane or higher. Substituted diamondoids preferably comprise from 1 to 10 and more preferably 1 to 4 substituents independently selected from the group consisting of alkyl, including linear (i.e., straight chain) alkyl, branched alkyl or cycloalkyl groups.
[0110] The term “heteroatom” refers to an atom selected from IIIB, non-C IVB, VB and VIB elements in the Periodic Table of the Elements, e.g. B, Al, Si, N, P, As, O, S, etc.
[0111] The terms “heterodiamondoid” and “hetero diamondoid” refer to diamondoid (as specifically defined) in which at least one cage carbon atom is replaced by a heteroatom. Heterodiamondoids include heterotriamantane, heterotetramantane, heteropentamantane, heterohexamantane, heteroheptamantane, heterooctamantane, heterononamantane, heterodecamantane, heteroundecamantane, heteroundecamantane and heterododecamantane. Substituted heterodiamondoids preferably comprise from 1 to 10 and more preferably 1 to 4 substituents independently selected from the group consisting of alkyl, including linear (i.e., straight chain) alkyl, branched alkyl or cycloalkyl groups.
[0112] The terms “functionalized heterodiamondoid” and “derivatized heterodiamandoid” refer to a heterodiamondoid which has at least one covalently bonded functional group.
[0113] The term “alkyl” refers to a linear saturated monovalent hydrocarbon group having 1 to 40 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms; or a branched saturated monovalent hydrocarbon group having 3 to 40 carbon atoms, preferably from 3 to 10 carbon atoms, and more preferably 3 to 6 carbon atoms. This term is exemplified by groups such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, n-hexyl, n-decyl, tetradecyl, and the like.
[0114] The term “functional group” refers to halos, hydroxyls, oxides, nitros, aminos, thios, sulfonyl halides, sulfonates, phosphines and the like, as well as such groups attached to hydrocarbyl materials such as alkyls, alkenyls, alkyaryls and aryls with or without substitution.
Synthesis of Heterodiamondoids
[0115] Prior to attempting an actual synthesis, it is often advantageous to utilize the methods of molecular modeling and computational chemistry in order to predict the properties of a desired molecule, and to facilitate the design of a synthetic pathway. These methods calculate the potential energy surface of a molecule, which takes into account the forces of interaction between the constituent atoms.
[0116] After optimizing the molecular structure and calculating the minimized energy, the heat of formation was calculated. The results of an exemplary calculation for the hetero-iso-tetramantane are provided in the table shown in FIG. 2 . In FIG. 2 , “X” represents a heteroatom that has been inserted into the diamond lattice substitutionally. The second column of the table denotes the position where the heteroatom replaces a host carbon atom, and these positons are either denoted “C-2” for secondary positions, or “C-3” for tertiary positions. Identification of secondary and tertiary positions is shown with four representative diamondoids in FIG. 1 and FIG. 2 . The third column of the table are the heats of formation in kcal/mol.
[0117] The present calculations serve to demonstrate that the preparation of such compounds is synthetically feasible.
[0118] A similar set of calculations was made for the hetero-[121212121] decamantane, with the results shown in Table 1:
[0000]
TABLE 1
Heteroatom
Heat of formation
(X)
Position
(Kcal/mol)
C
−76.08
O
C-2
−103.45
S
C-2
−58.71
Se
C-2
−53.26
B
C-2
−42.40
C-3
−31.76
N
C-2
−56.91
C-3
−48.15
P
C-2
−28.44
C-3
−27.10
As
C-2
−43.59
C-3
−44.52
[0119] Similar to the example above, those calculations indicate that the synthesis of the heterodiamondoids are feasible.
[0120] A final example of a calculation is presented for hetero-[1212121212] undecamantane. For this particular isomer, the results of the calculations are shown in Table 2. In this example, the substitution is made at either the secondary C-2 atom at position 25, or the C-3 atom at position 26. The results of the calculation are shown in Table 2:
[0000]
TABLE 2
Heteroatom
Heat of formation
(X)
Position
(Kcal/mol)
C
−79.81
O
C-2
106.92
S
C-2
61.95
Se
C-2
56.82
B
C-2
−45.45
C-3
−35.85
N
C-2
−60.32
C-3
−52.45
P
C-2
−32.05
C-3
−29.80
As
C-2
−47.70
C-3
−47.96
[0121] Once again, the calculations indicate that the synthesis is feasible.
[0122] Thus, molecular modeling calculations have demonstrated that it is feasible to substitutionally position a boron, nitrogen, phosphorus, arsenic, oxygen, or sulfur heteroatom into the diamond lattice of a diamondoid.
[0123] Starting from the diamondoids, there are several methodlogies for the synthesis of heterodiamondoids such as oxa and thia diamondoids. For example, FIGS. 3-5 illustrate three different synthesis pathways to oxadiamondoids. FIG. 6 shows two different pathways to thiadiamondoids. For another example, FIGS. 7 and 8 show different ways to prepare azadiamondoids. It is understood that while in the FIGS. 3-8 only iso-tetramantane is shown as the starting diamondoid, triamantane and other higher diamondoids may also be used.
[0124] Nitrogen heterodiamondoids may be synthesized by the method of T. Sasaki et al., Synthesis of adamantane derivatives. 39 . Synthesis and acidolysis of 2- azidoadamantanes. A facile route to 4- azahomoadamant -4- enes, Heterocycles Vol. 7, No. 1, p. 315 (1977). The procedure consists of a substitution of a hydroxyl group with an azide function via the formation of a carbocation, followed by acidolysis of the azide product.
[0125] Another synthetic pathway is provided by T. Sasaki et al., Synthesis of Adamantane Derivatives. XII. The Schmidt Reaction of Adamantane -2- one, J. Org. Chem. Vol. 35, No. 12, p. 4109 (1970).
[0126] Alternatively, a 1-hydroxy-2-azaadamantane may be synthesized from 1,3-dibromoadamantane, as reported by A. Gagneux et al. in 1- Substituted 2- heteroadamantanes, Tetrahedron Letters No. 17, pp. 1365-1368 (1969). This is a multiple-step process, wherein first the di-bromo starting material is heated to a methyl ketone, which subsequently undergoes ozonization to a diketone. The diketone is heated with four equivalents of hydroxylamine to produce a 1:1 mixture of cis and trans-dioximes; this mixture is hydrogenated to the compound 1-amino-2-azaadamantane dihydrochloride. Finally, nitrous acid transforms the dihydrochloride to the hetero-adamantane 1-hydroxy-2-azadamantane.
[0127] Alternatively, a 2-azaadamantane compound may be synthesized from a bicyclo[3.3.1]nonane-3,7-dione, as reported by J. G. Henkel and W. C. Faith, in Neighboring group effects in the β - halo amines. Synthesis and solvolytic reactivity of the anti -4- substituted 2- azaadamantyl system , in J. Org. Chem. Vol. 46, No. 24, pp. 4953-4959 (1981). The dione may be converted by reductive amination (although the use of ammonium acetate and sodium cyanoborohydride produced better yields) to an intermediate, which may be converted to another intermediate using thionyl choloride. Dehalogenation of this second intermediate to 2-azaadamantane was accomplished in good yield using LiAlH 4 in DME.
[0128] A synthetic pathway that is related in principal to one useful in the present invention was reported by S. Eguchi et al. in A novel route to the 2- aza - adamantyl system via photochemical ring contraction of epoxy 4- azahomoadamantanes, J. Chem. Soc. Chem. Commun, p. 1147 (1984). In this approach, a 2-hydroxyadamantane is reacted with a NaN 3 based reagent system to form the azahomoadamantane, with is then oxidized by m-chloroperbenzoid acid (m-CPBA) to give an epoxy 4-azahomoadamantane. The epoxy is then irradiated in a photochemical ring contraction reaction to yield the N-acyl-2-aza-adamantane.
[0129] An exemplary reaction pathway for synthesizing a nitrogen-containing hetero iso-tetramantane is illustrated in FIG. 7 . It will be known to those of ordinary skill in the art that the reaction conditions of the pathway depicted in FIG. 7 will be substantially different from those of Eguchi due to the differences in size, solubility, and reactivities of tetramantane in relation to adamantane. A second pathway available for synthesizing nitrogen-containing heterodiamondoids is illustrated in FIG. 8 .
[0130] A phosphorus-containing heterodiamondoid may be synthesized by adapting the pathway outlined by J. J. Meeuwissen et. al in Synthesis of 1- phosphaadamantane, Tetrahedron Vol. 39, No. 24, pp. 4225-4228 (1983). It is contemplated that such a pathway may be able to synthesis heterodiamondoids that contain both nitrogen and phosphorus atoms substitutionally positioned in the diamondoid structure, with the advantages of having two different types of electron-donating heteroatoms in the same structure.
[0131] After preparing the heterodiamondoids, they may be functionalized with at least one functional group. Representative pathways are provided in the Examples. Additional disclosure of derivatization methods is provided below and in FIGS. 9-23 .
Functionalization of Heterodiamondoids and the Derivatives Therefrom
[0132] Table 3 provides a representative list of heterodiamondoid derivatives.
[0000]
TABLE 3
Representative Heterodiamondoid Derivatives
HETERODIAMONDOID
FUNCTIONAL GROUP
hetero trimantane-hetero undecamantane
—F
hetero trimantane-hetero undecamantane
—Cl
hetero trimantane-hetero undecamantane
—Br
hetero trimantane-hetero undecamantane
—I
hetero trimantane-hetero undecamantane
—OH
hetero trimantane-hetero undecamantane
—CO 2 H
hetero trimantane-hetero undecamantane
—CO 2 CH 2 CH 3
hetero trimantane-hetero undecamantane
—COCl
hetero trimantane-hetero undecamantane
—SH
hetero trimantane-hetero undecamantane
—CHO
hetero trimantane-hetero undecamantane
—CH 2 OH
hetero trimantane-hetero undecamantane
—NH 2
hetero trimantane-hetero undecamantane
—NO 2
hetero trimantane-hetero undecamantane
═O (keto)
hetero trimantane-hetero undecamantane
—CH═CH 2
hetero trimantane-hetero undecamantane
—C≡CH
hetero trimantane-hetero undecamantane
—C 6 Hphd 5
hetero trimantane-hetero undecamantane
—NHCOCH 3
hetero trimantane-hetero undecamantane
—NHCHO
hetero trimantane-hetero undecamantane
—CH 2 Br
hetero trimantane-hetero undecamantane
—CH═CHBr
hetero trimantane-hetero undecamantane
—C≡CBr
hetero trimantane-hetero undecamantane
—C 6 H 4 Br
hetero trimantane-hetero undecamantane
—CH 2 Cl
hetero trimantane-hetero undecamantane
—CH═CHCl
hetero trimantane-hetero undecamantane
—C≡CCl
hetero trimantane-hetero undecamantane
—C 6 H 4 Cl
hetero trimantane-hetero undecamantane
—CH 2 OH
hetero trimantane-hetero undecamantane
—C 6 H 4 OH
hetero trimantane-hetero undecamantane
—OCOCl
hetero trimantane-hetero undecamantane
—OCSCl
hetero trimantane-hetero undecamantane
—OCH 3
hetero trimantane-hetero undecamantane
—OCH 2 CH 2 NH 2
hetero trimantane-hetero undecamantane
—OCH 2 C(CH 3 ) 2 N(CH 3 ) 2
hetero trimantane-hetero undecamantane
—O(CH 2 ) 5 NH 2
hetero trimantane-hetero undecamantane
—O(CH 2 ) 5 NH 2 HCl
hetero trimantane-hetero undecamantane
hetero trimantane-hetero undecamantane
hetero trimantane-hetero undecamantane
—OCH 2 CH 2 NHC(O)CH 3
hetero trimantane-hetero undecamantane
—C≡N
hetero trimantane-hetero undecamantane
—CH 2 CO 2 H
hetero trimantane-hetero undecamantane
—CH 2 CO 2 CH 3
hetero trimantane-hetero undecamantane
—CF 3 CO 2 H
hetero trimantane-hetero undecamantane
—COCH 3
hetero trimantane-hetero undecamantane
—N═C═S
hetero trimantane-hetero undecamantane
—N═C═O
hetero trimantane-hetero undecamantane
—N═S═O
hetero trimantane-hetero undecamantane
—PH 2
hetero trimantane-hetero undecamantane
—POCl 2
hetero trimantane-hetero undecamantane
—PO(OH) 2
hetero trimantane-hetero undecamantane
—SO 2 H
hetero trimantane-hetero undecamantane
—OSO 3 H
hetero trimantane-hetero undecamantane
—SO 2 CH 3
hetero trimantane-hetero undecamantane
—SOCl
hetero trimantane-hetero undecamantane
—SO 2 OCH 3
hetero trimantane-hetero undecamantane
—SON(CH 3 ) 2
hetero trimantane-hetero undecamantane
—N 3
hetero trimantane-hetero undecamantane
hetero trimantane-hetero undecamantane
hetero trimantane-hetero undecamantane
hetero trimantane-hetero undecamantane
Heterodiamondoid-Containing Polymers
[0133] Polymerization of polymerizable heterodiamondoid derivatives to form heterodiamondoid-containing polymers is similar to what we have already disclosed in U.S. patent application Ser. No. 10/046,486 filed on Jan. 16, 2002 entitled “polymerizable higher diamondoid derivatives”, which is hereby incorporated herein by reference. FIGS. 24-33 present some exemplary heterodiamondoid-containing polymers and the polymerization reactions which provide them.
EXAMPLES
[0134] Example 1 describes a most universal route for isolating higher diamondoids components which can be applied to all feedstocks used herein. This process uses HPLC as its final isolation step.
[0135] Example 2 describes methods that could be used to prepare a oxadiamondoid from a diamondoid-containing feedstock.
[0136] Example 3 describes methods that could be used to prepare a azadiamondoid from a diamondoid-containing feedstock.
[0137] Examples 4-10 describe methods that could be used to prepare heterodiamondoids (e.g. oxa-, thia-, aza-diamondoids, etc.) from diamondoids.
[0138] Examples 11-46 describe methods that could be used to prepare heterodiamondoid derivatives.
[0139] Examples 47-64 describe methods that could be used to prepare heterodiamondoid-containing polymers.
Example 1
[0140] This Example has seven steps.
[0141] Step 1. Feedstock selection
[0142] Step 2. GCMC assay development
[0143] Step 3. Feedstock atmospheric distillation
[0144] Step 4. Vacuum fractionation of atmospheric distillation residue
[0145] Step 5. Pyrolysis of isolated fractions
[0146] Step 6. Removal of aromatic and polar nondiamondoid components
[0147] Step 7. Multi-column HPLC isolation of higher diamondoids
[0148] a) First column of first selectivity to provide fractions enriched in specific higher diamondoids
[0149] b) Second column of different selectivity to provide isolated higher diamondoids.
[0150] This example is written in terms of isolating several hexamantanes but the other higher diamondoids can be isolated using it, as well.
Step 1—Feedstock Selection
[0151] Suitable starting materials were obtained. These materials included a gas condensate, Feedstock A, and a gas condensate containing petroleum components, Feedstock B. Although other condensates, petroleums, or refinery cuts and products could have been used, these two materials were chosen due to their high diamondoid concentration, approximately 0.3 weight percent higher diamondoids, as determined by GC and GC/MS. Both feedstocks were light colored and had API gravities between 19 and 20° API.
Step 2—GC/MS Assay Development
[0152] Feedstock A was analyzed using gas chromatography/mass spectrometry to confirm the presence of target higher diamondoids and to provide gas chromatographic retention times for these target materials. This information is used to track individual higher diamondoids through subsequent isolation procedures.
Step 3—Feedstock Atmospheric Distillation
[0153] A sample of Feedstock B was distilled into a number of fractions based on boiling points to separate the lower boiling point components (nondiamondoids and lower diamondoids) and for further concentration and enrichment of particular higher diamondoids in various fractions.
Step 4—Fractionation of Atmospheric Distillation Residue by Vacuum Distillation
[0154] The Feedstock B atmospheric residium from Step 3 (comprising 2-4 weight percent of the original feedstock) was distilled into fractions containing higher diamondoids.
Step 5—Pyrolysis of Isolated Fractions
[0155] A high-temperature reactor was used to pyrolyze and degrade a portion of the nondiamondoid components in various distillation fractions obtained in Step 4 thereby enriching the diamondoids in the residue. The pyrolysis process was conducted at 450° C. for 19.5 hours.
Step 6—Removal of Aromatic and Polar Nondiamondoid Components
[0156] The pyrolysate produced in Step 5 was passed through a silica-gel gravity chromatography column (using cyclohexane elution solvent) to remove polar compounds and asphaltenes.
Step 7—Multi-Column HPLC Isolation of Higher Diamondoids
[0157] An excellent method for isolating high-purity higher diamondoids uses two or more HPLC columns of different selectivities in succession.
[0158] The first HPLC system consisted of two Whatman M20 10/50 ODS columns operated in series using acetone as mobile phase at 5.00 mL/min. A series of HPLC fractions were taken.
[0159] Further purification of this HPLC fraction was achieved using a Hypercarb stationary phase HPLC column having a different selectivity in the separation of various hexamantanes than the ODS column discussed above.
Example 2
Oxatetramantanes from a Feedstock Containing Tetramantanes (FIG. 3 )
[0160] A fraction as described in Example 1 containing all of the tetramantanes including some alkyltetramantanes and hydrocarbon impurities was obtained.
[0161] A solution of 200 mg of the above feedstock containing tetramantanes in 6.1 g of methylene chloride was mixed with 4.22 g of a solution of 1.03 g (13.5 mmol) of peracetic acid in ethyl acetate. While being stirred vigorously, the solution was irradiated with a 100-watt high intensity UV light. Gas evolution was evident from the start. The temperature was maintained at 40-45° C. for an about 21-hour irradiation period. Then the solution was concentrated to near dryness, treated twice in succession with 10-mL portions of toluene and reevaporated to dryness followed by CH 2 Cl 2 extraction (15 mL×2). The combined organic extract was then dried over Na 2 SO 4 , Solvent was evaporated to almost dryness to yield a product which was subjected to GC/MS characterization showing the presence of a mixture hydroxylated tetramantanes as shown in FIG. 3 . The chromatograms and mass spectra illustrating the presence of hydroxylated tetramantanes are provided as FIGS. 35-38 .
[0162] To a portion of the hydroxylated tetramantanes in dry benzene (10 mL) was added mercury(II) oxide (100 mg) and iodine (170 mg). After the addition, the reaction mixture was irradiated for about 7 h in an atmosphere of nitrogen by the procedure reported by Suginome et al. ( J. Org. Chem., 1984, 49, 3753). Work-up gave a product mixture which was subjected to GC/MS characterization showing the presence of the oxatetramantane product 3 of FIG. 3 . The chromatogens and mass spectra are provided as FIGS. 39-41 .
Example 3
Azatetramantanes from a Feedstock Containing a Mixture of Tetramantane Isomers
[0163] In the next step, an azahomo tetramantane-ene may be produced from the above hydroxylated tetramantanes, or from photooxidized tetramantanes. To a stirred and ice cooled mixture of 98% methanesulfonic acid (1.5 mL) and dichloromethane (3.5 ml) was added solid sodium azide (1.52 g, 8.0 mmol). To that mixture was added the hydroxylated tetramantanes (2) as prepared in Example 2 above. To this resulting mixture was added in small increments sodium azide (1.04 g, 16 mmol) over a period of about 0.5 h. Stirring was continued for about 8 h at 20-25° C., and then the mixture was poured into ice water (ca. 10 ml). The aqueous layer was separated, washed with CH 2 Cl 2 (3 mL), basified with 50% aqueous KOH-ice, and extracted with CH 2 Cl 2 (10 mLx4). The combined extracts were dried with Na 2 SO 4 , and the solvent was removed to afford a brownish oil product. The product was characterized by GC/MS to show the presence of azahomo tetramantane-ene isomers (14). The chromatograms and mass spectra showing the azahomo molecules are shown in FIGS. 42-46 .
[0164] In the next step, an epoxy azahomo tetramantane was made from the azahomo tetramantane-enes. The above mixture was treated with m-CPBA (1.1 eq.) in CH 2 Cl 2 —NaHCO 3 at a temperature of about 20° C. for about 12 h, and the reaction mixture was then worked up with a CH 2 Cl 2 extraction to afford a crude product that was characterized by GC/MS ( FIGS. 47-51 ) to show the presence of epoxy azahomo tetramantane.
[0165] In the next step, a mixture of N-formyl aza tetramantanes was prepared from the epoxy azahomo tetramantane mixture by irradiating the epoxy aza tetramantane mixture in cyclohexane using a high intensity Hg lamp for about 0.5 hours. The reaction was carried out in an argon atmosphere. Generally speaking, a simpler reaction product was obtained if the reaction was allowed to proceed for only a short time; longer periods gave a complex mixture. The initial product was characterized by GC/MS ( FIGS. 52-56 ) as a mixture of N-formyl aza tetramantanes.
[0166] In a final step, aza tetramantanes were prepared from the above described N-formyl aza tetramantanes by mixing the N-formyl aza tetramantanes with 10 mL of 15% hydrochloric acid. The resultant mixture was heated to a boil for about 24 hours. After cooling, the mixture was subjected to a typical workup to afford a product which was characterized by GC/MS ( FIGS. 57-63 ) showing the presence of aza tetramantanes.
Example 4
Oxidation of Hydroxylated Compound 2 to Keto Compound 1
[0167] Photohydroxylated iso-tetramantane containing a mixture of C-2 and C-3 hydroxylated iso-tetramantanes dissolved in acetone is prepared as set out in Example 2. The oxygenated components go into the solution but not all of the unreacted iso-tetramantane. Chromic acid-sulfuric acid solution is added dropwise to the solution until an excess is present, and the reaction mixture is stirred overnight. The acetone solution is decanted from the precipitated chromic sulfate and the unreacted iso-tetramantane, and is dried with sodium sulfate. The unreacted iso-tetramantane is recovered by dissolving the chromium salts in water and filtering. Evaporation of the acetone solution affords a white solid. This crude solid is chromatographed on alumina with standard procedures eluting first with 1:1 (v/v) benzene/light petroleum ether followed by ethyl ether or a mixture of ethyl ether and methanol (95:5 v/v) to collect the unreacted iso-tetramantane and the keto compound 1 ( FIG. 3 ), respectively. Further purification by recrystallization from cyclohexane affords a pure product 1.
[0168] Alternatively, iso-tetramantane is directly oxidized to keto compound 1 according to the procedures of McKervey et al. ( J. Chem. Soc., Perkin Trans. 1, 1972, 2691).
Reduction of Keto Compound 1 to C-2 Hydroxylated iso-Tetramantane 2a
[0169] As shown in FIG. 3 , the keto compound 1 is reduced with lithium aluminum hydride (a little excess) in ethyl ether at low temperatures to prepare C-2 hydroxylated iso-tetramantane 2a. After completion of the reaction, the reaction mixture is worked up by adding saturated Na 2 SO 4 aqueous solution to decompose excess hydride at low temperature. Decantation from the precipitated salts gives a dry ether solution, which, when evaporated, affords a crude monohydroxylated iso-tetramantane substituted at the secondary carbon, i.e. C-2 tetramantan-ol which is purified by recrystallization from cyclohexane.
C-2 Methyl Hydroxyl iso-Tetramantane 2b from Keto Compound 1
[0170] Alternatively, as shown in FIG. 3 , to a stirred solution of keto compound 1 (2 mmol) in dry THF (20 mL) at −78° C. (dry ice/methanol) is added dropwise a 0.8 molar solution (2.8 mL, 2.24 mmol) of methyllithium in ether. Stirring is continued for about 2 h at −78° C. and for another about 1 h at room temperature. Then, saturated ammonium chloride solution (1 mL) is added, and the mixture extracted with ether (2×30 mL). The organic layer is dried with sodium sulfate and concentrated to give the product 2b which is subjected to further purification by either chromatography or recrystallization.
Oxa iso-Tetramantane 3 from C-2 Hydroxylated iso-Tetramantane 2a
[0171] A solution of C-2 hydroxylated iso-tetramantane 2a (1.32 mmol) in dry benzene (60 mL) containing mercury(II) oxide (850 mg) and iodine (1.006 g) is irradiated for about 7 h in an atmosphere of nitrogen by the procedure reported by Suginome et al. ( J. Org. Chem., 1984, 49, 3753). Work-up as reported gives a product which is subjected to preparative TLC on silica gel benzene/ether to give the product 3, as well as some amount of lactone 4 and the starting material 2a.
Oxa iso-Tetramantane 3 from C-2 Methyl Hydroxylated iso-Tetramantane 2b
[0172] A solution of C-2 methyl hydroxyl iso-tetramantane 2b (0.6 mmol) in dry benzene (30 mL) containing mercury(II) oxide (392 mg) and iodine (459 mg) is irradiated for about 3 h in an atmosphere of nitrogen by the above procedure. Work-up of the solution gives a product which is subjected to preparative TLC on silica gel with benzene/ether to give the product 3.
Oxa iso-Tetramantane 3 from C-2 Methyl Hydroxyl iso-Tetramantane 2b
[0173] C-2 methyl hydroxyl iso-tetramantane 2b (6.02 mmol) is added to a solution of TFPAA (trifluoroperacetic acid) in TFAA (trifluoroacetic acid) (13 g, 48.5 mmol) at 0° C. After being stirred for about 15 min. at 0° C., the reaction mixture is allowed to warm to r.t., stirring for about 1 h, and then poured into a solution of 15% NaOH (50 mL) with ice. The mixture is extracted with CH 2 Cl 2 (3×15 mL). The combined extract is then washed with water and 5% aqueous Na 2 SO 3 . The organic layer is dried over Na 2 SO 4 and the solvent evaporated. The residue is separated on a silica column eluting with a mixture of hexane-ether to afford the preduct oxa iso-tetramantane 3.
Example 5
Preparation of Lactone 4
[0174] Lactone 4 of FIG. 4 is prepared according to the general procedure of [Udding et al., Tetrahedron Lett., 1968, 5719].
Preparation of Compound 5a from Compound 4
[0175] To a solution of lactone 4 (4.5 mmol) in dry toluene (80 mL) at −78° C. (cooled by dry ice/methanol) is added dropwise diisobutylaluminium hydride (20% in hexane, 5 mL) over a period of 20 min. The solution is stirred for 2 h at −78° C. and then poured into ice water. After removal of the precipitates, the solution is washed with water (1×50 mL) and dried with sodium sulfate. The solvent is evaporated to give the crude lactol 5a, which is recrystallized from hexane for further purification.
Preparation of Compound 5b from Compound 4
[0176] To a stirred solution of lactone 4 (2 mmol) in dry tetrahydrofuran (THF) (20 mL) at −78° C. (dry ice/methanol) is added dropwise a 0.8 molar solution (2.8 mL, 2.24 mmol) of methyllithium in ether. Stirring is continued for about 2 h at −78° C. and for about 1 h at room temperature. Then, saturated ammonium chloride solution (1 mL) is added, and the mixture extracted with ether (2×30 mL). The organic layer is dried with sodium sulfate and concentrated to give the crystalline product 5b which is recrystallized from petroleum ether for further purification.
Preparation of Compound 6a by Irradiation of 5a
[0177] To a solution of lactol 5a (1.2 mmol) in dry benzene (60 mL) containing pyridine (0.5 mL) is added mercury(II) oxide (520 mg) and iodine (610 mg). The solution is placed in a Pyrex vessel, flushed with nitrogen, and irradiated by a 100-W high-pressure mercury arc. The irradiation is discontinued after about 2 h. The solution is then washed with aqueous 5% sodium thiosulfate solution (30 mL), water (50 mL), and saturated sodium chloride solution (50 mL) and is dried with sodium sulfate. The solvent is evaporated to give the crude product 6a. Preparative TLC of this product with benzene affords two fractions A and B in the order of decreasing mobility. Fraction A is product 6a while fraction B is lactone 4.
Preparation of Compound 6b from 5b
[0178] To a solution of lactol 5b (1.2 mmol) in dry benzene (55 mL) containing pyridine (1 mL) are added mercury(II) oxide (477 mg) and iodine (588 mg). The solution is photolyzed as in the case of lactol 5a to give a crude product. The product is subjected to preparative TLC with benzene to give product 6b.
Example 6
Fragmentation of Keto Compound 1 to Unsaturated Carboxylic Acid 9 of FIG. 5
[0179] Fragmentation of iso-tetramantone 1 as prepared above to the unsaturated carboxylic acid 9 by an abnormal Schmidt reaction likewise follows McKervey et al. ( Synth. Commun., 1973, 3, 435) and is analogous to the behavior reported for adamantane and diamantane (Sasaki et al., J. Org. Chem., 1970, 35, 4109; Fort, Jr. et al., J. Org. Chem., 1981, 46(7), 1388).
Preparation of Compound 10 (exo- and endo) from Acid 9
[0180] To 4.6 mmol of the carboxylic acid 9 are added 12 mL of glacial acetic acid and 3.67 g (4.48 mmol) of anhydrous sodium acetate. The mixture is stirred and heated to about 70° C. Lead(IV) acetate (3.0 g, 6.0 mmol, 90% pure, 4% acetic acid) is added in three portions over 30 min. Stirring is continued for 45 min at 70° C. The mixture is then cooled down to room temperature and diluted with 20 mL of water. The resulting suspension is stirred with 20 mL of ether, and a few drops of hydrazine hydrate are added to the dissolve the precipitated lead dioxide. The ether layer then is separated, washed several times with water and once with saturated sodium bicarbonate, and dried over anhydrous sodium sulfate. Removal of the ether gives an oily material from which a mixture of the two isomers (exo- and endo-) of compound 10 is obtained. Further purification and separation of the stereochemical isomers (exo- and endo-) can be achieved by distillation under vacuum.
Preparation of Compound 11 (exo- or endo) from Compound 10 (exo- or endo)
[0181] To a solution of compound 10 (0.862 mmol) in 5 mL of anhydrous ether is added 0.13 g (3.4 mmol) of lithium aluminum hydride, and the mixture is refluxed with stirring for about 24 h. The excess lithium aluminum hydride is destroyed by addition of water dropwise, and the precipitated lithium and aluminum hydroxides are dissolved in excess 10% hydrochloric acid. The ether layer is separated, washed with water, dried over anhydrous sodium sulfate, and evaporated to give compound 11 (mixtures of exo-11 and endo-11 isomers if using mixtures of exo-10 and endo-10). Further purification can be achieved by recrystallization from methanol-water.
Preparation of Compound 12 from Compound 11 (exo- and endo-Mixture)
[0182] A solution of a mixture of the alcohols 11 (1.05 mmol) in 5 mL of acetone is stirred in an Erlenmeyer flask at 25° C. To this solution is added dropwise 8 N chromic acid until the orange color persists, the temperature being kept at 25° C. The orange solution is then stirred at 25° C. for about additional 3 h. Most of the acetone is removed, and 5 mL of water is added to the residue. The aqueous mixture is extracted twice with ether, and the combined extracts are washed with saturated sodium bicarbonate, dried over anhydrous sodium sulfate, and evaporated to give crude 12. Sublimation on a steam bath gives pure 12.
Preparation of Compound 12 from exo-11
[0183] A solution of exo-11 (1.05 mmol) in 5 mL of acetone is stirred in an Erlenmeyer flask at 25° C. To this solution is added dropwise 8 N chromic acid until the orange color persisted, the temperature being kept at 25° C. The orange solution is then stirred at 25° C. for about additional 3 h. Most of the acetone is removed, and 5 mL of water is added to the residue. The aqueous mixture is extracted twice with ether, and the combined extracts are washed with saturated sodium bicarbonate, dried over anhydrous sodium sulfate, and evaporated to give crude 12. Sublimation on a steam bath gives pure 12.
Preparation of Compound 12 from Acid 9
[0184] A solution of the carboxylic acid 9 (4.59 mmol) in 15 mL of dry THF is stirred under dry argon and cooled to 0° C. A solution of 1.5 g (13.76 mmol) of lithium diisopropylamide in 25 mL of dry THF under argon is added through a syringe to the solution of 9 at such a rate that the temperature does not rise above 10° C. The resulting solution of the dianion of 9 is stirred at 0° C. for about 3 h. It is then cooled to −78° C. with a dry ice-acetone bath, and dry oxygen is bubbled slowly through the solution for about 3 more. A mixture of about 10 mL of THF and 1 mL water is added to the reaction mixture, which is then allowed to warm to room temperature and is stirred overnight. The solution is concentrated to about 10 mL at water pump pressure, poured into excess 10% HCl, and extracted with ether. The ether layer is washed with 5% NaOH to remove unreacted 9, which is recovered by acidification of the basic wash. The ether layer is dried over anhydrous sulfate and stripped to yield crude 9. Sublimation on a steam bath at 3-5 torr gives pure product.
Preparation of endo-11 from Compound 12
[0185] To a solution of ketone 12 (0.9 mmol) in 5 mL of anhydrous ether is added 0.13 g (3.4 mmol) of lithium aluminum hydride, and the mixture is stirred and refluxed for about 24 h. The excess lithium aluminum hydride is destroyed by dropwise addition of water, and the precipitated lithium and aluminum hydroxides are dissolved in excess 10% HCl. The ether layer is separated and dried over anhydrous sodium sulfate. Removal of the solvent gives the crude but stereochemically pure endo-11, which is further purified by sublimation on a steam bath under water pump pressure.
Oxa iso-tetramantane 3 from endo-11
[0186] To endo-11 (1.58 mmol) is added 25 mL of 50% sulfuric acid, and the solution is stirred vigorously at room temperature for about 24 h. The reaction mixture is then poured onto 100 g ice and the mixture extracted twice with ether. The ether extract is dried over anhydrous sodium sulfate and evaporated. The crude product is purified by sublimation on a steam bath at water pump pressure.
Example 7
Oxa iso-Tetramantane 3 from 6a or 6b with Methyllithium as Shown in FIG. 4
[0187] To a stirred solution of compound 6a (0.19 mmol) in dry THF (5 mL), a 0.8 molar solution (0.52 mL, 0.424 mmol) of methyllithium in ether is added dropwise at −78° C. Stirring is continued for about 1 h at −78° C. and for about another 1 h at room temperature. Water (10 mL) is then added and the mixture is extracted with ether (2×20 mL). The organic layer is washed with water (20 mL) and saturated sodium chloride solution (20 mL) and is dried with sodium sulfate. The solvent is evaporated to give crystals. The product is further purified by preparative TLC on silica gel using mixtures of benzene and ether.
Oxa iso-Tetramantane 3 from 6a by Column Chromatography on Silica Gel
[0188] Compound 6a (0.09 mmol) in dichloromethane (1 mL) is adsorbed on a column of silica gel for about 24 h. Elution of the column with dichloromethane gives the product 3 and some starting compound 6a.
Oxa iso-Tetramantane 3 from 6a Thermally
[0189] Compound 6a (0.09 mmol) is heated at 60° C. for about 30 min., and then subjected to preparative TLC with benzene/ether to yield the product 3 and the starting material 6a.
Example 8
Preparation of Thia-iso-Tetramantane Starting from iso-Tetramantone 6b of FIG. 6
Preparation of Compound 7 from 6b
[0190] Compound 6b is prepared as described in a previous example. To a solution of compound 6b (0.78 mmol) in dry carbon tetrachloride (4 mL) is added to iodotrimethylsilane (312 mg, 1.56 mmol) at room temperature and the mixture is stirred for about 4 h. Water (20 mL) is then added and the mixture is extracted with ether (2×30 mL). The organic extract is washed with 5% sodium thiasulfate (20 mL), water, and saturated sodium chloride solution (30 mL) and is dried with sodium sulfate. The solvent is evaporated to give the crystalline product 7, which decomposes upon heating above about 90° C.
Preparation of Thia iso-Tetramantane 8 from Compound 7
[0191] Compound 7 (1 mmol) is dissolved in ethanol (10 mL) by warming Sodium sulfide (Na 2 S.9H 2 O, 950 mg, 3.96 mmol) is added and the mixture is refluxed for about 10 h. Then, water (30 mL) is added and the mixture is extracted with ether (2×30 mL). The organic extract is washed with water (40 mL) and with saturated sodium chloride solution (40 mL) and is dried with sodium sulfate. The solvent is evaporated to give crystalline thia iso-tetramantane 8 which is further purified by preparative TLC on silica gel (hexane/benzene).
Example 9
Preparation of Compound 13 from Compound 12 (FIG. 6 )
[0192] Compound 12 is prepared as described in a previous example starting from iso-tetramantone 1. Hydrogen sulfide is passed continuously for 2 days through a solution of compound 12 (1.06 mmol) in 15 mL of absolute ethanol. The solution is kept acidic by passing hydrogen chloride during every other 12-h period. The reaction mixture is kept at 0° C. during the passage of the gases. The resulting orange solution is extracted with 50 mL of ether in portions. The ether extracts are washed twice with water, dried over anhydrous sodium sulfate, and stripped to yield an orange semisolid. No further purification is needed and the material is used directly in the following reaction.
Thia iso-Tetramantane 8 from Compound 13
[0193] The crude compound 13 is dissolved in 100 mL of anhydrous ether, and 500 mg (13.16 mmol) of lithium aluminum hydride is added. The mixture is stirred at reflux for about 2 days. Excess lithium aluminum hydride is destroyed with water, and the precipitated lithium and aluminum hydroxides are dissolved in excess 10% HCl. The layers are separated, and the aqueous phase is extracted with 50 mL of ether. The combined ether extracts are dried over anhydrous sodium sulfate and stripped. Sublimation of the residue on a steam bath at water pump pressure gives the product 8 contaminated with a small amount of endo-11. This mixture is chromatographed on neutral alumina. Elution with hexane gives pure 8; subsequent elution with ether gives endo-11. Further purification of 8 is by sublimation on a steam bath at water pump pressure.
Example 10
Preparation of Aza iso-Tetramantane from iso-Tetramantane (FIGS. 7 & 8 )
[0194] In this example, an aza iso-tetramantane is prepared from a single tetramantane isomer, iso-tetramantane, as shown in FIGS. 7-8 . As with the reactions using a mixture of tetramantanes shown in Example 2, this synthetic pathway begins with the photo-hydroxylation of iso-tetramantane using the method of Example 2 or chemical oxidation/reduction to the hydroxylated compound 2a shown in FIG. 7 .
[0195] This photo-hydroxylated iso-tetramantane containing a mixture of C-2 and C-3 hydroxylated iso-tetramantanes is converted to keto compound 1 via the process set out in Example 4.
[0196] In the next step, the azahomo iso-tetramantane-ene 14 is prepared from the hydroxylated compound 2 using the general method set out in Example 3.
[0197] In the next step, an epoxy azahomo iso-tetramantane 15 is prepared also as shown in Example 3.
[0198] In the next step, N-acyl aza iso-tetramantane 16b is prepared from the epoxy azahomo iso-tetramantane 15b by irradiating the epoxy azahomo iso-tetramantane 15b in cyclohexane for about 0.5 hours with a UV lamp. The radiation passes through a quartz filter and the reaction is carried out under an argon atmosphere. Generally speaking, a single product is formed when the reaction is allowed to proceed for only a short time: longer periods gives a complex mixture of products. Products may be isolated by chromatographic techniques.
[0199] N-formyl aza iso-tetramantane 16a can be similarly prepared from the epoxy azahomo iso-tetramantane 15a.
[0200] In the next step, the aza iso-tetramantane 17 is prepared from N-acyl aza-isotetramantane 16b by heating the N-acyl aza iso-tetramantane 16b (5 mmol) to reflux for about 5 hours with a solution of 2 g powdered sodium hydroxide in 20 mL diethylene glycol. After cooling, the mixture is poured into 50 mL water and extracted with ethyl ether. The ether extract is dried with potassium hydroxide. The ether is distilled off to afford the product aza iso-tetramantane 17. The hydrochloride salt is generally prepared for analysis. Thus, dry hydrogen chloride is passed into the ether solution of the amine, whereby the salt separates out as a crystalline compound. The salt may be purified by dissolving it in ethanol, and precipitating with absolute ether. Typically, the solution is left undisturbed for several days to obtain complete crystallization.
[0201] Alternatively, the aza iso-tetramantane 17 may be prepared from the N-formyl aza iso-tetramantane 16a by mixing the N-formyl aza iso-tetramantane 16a (2.3 mmol) with 10 mL of 15% hydrochloric acid as shown in Example 3.
Example 11
Preparation of the Aza iso-tetramantane 17 by Fragmentation of a Keto Compound 1 (FIG. 8 )
[0202] To a solution of compound 12 ( FIG. 5 ) (1.6 mmol) in a mixture of pyridine and 95% ethanol (1:1) is added 250 mg (3.6 mmol) of hydroxylamine hydrochloride, and the mixture is stirred at reflux for about 3 days. Most of the solvent is evaporated in a stream of air, and the residue is taken up in 25 mL of water. An ether extract of the aqueous solution is washed with 10% HCl to extract the oxime 18. Neutralization of the acid wash with 10% sodium hydroxide precipitates the oxime 18, which is filtered off and recrystallized from ethanol-water.
[0203] In a final step, the aza iso-tetramantane 17 is prepared from compound 18 by the dropwise addition of a solution of compound 18 (0.98 mmol) in 25 mL of anhydrous ether to a stirred suspension of 250 mg (6.58 mmol) of lithium aluminum hydride in 25 mL of anhydrous ether. The mixture is stirred at reflux for about 2 days. Excess lithium aluminum hydride is destroyed with water, and the precipitated lithium and aluminum hydroxides are dissolved in excess 25% sodium hydroxide. The resulting basic solution is extracted twice with ether, and the combined extracts are then washed with 10% HCl. Neutralization of the acidic wash with 10% sodium hydroxide precipitates product 6, which is extracted back into fresh ether. The ether solution is dried over anhydrous sodium sulfate and stripped. The crude product is purified by repeated sublimation on a steam bath under vacuum.
Example 12
Monobromination of Heterodiamondoids
[0204] As shown in FIG. 13 , a heterodiamondoid (7.4 mmol) is mixed with anhydrous bromine (74 mmol) in a 150 mL round bottom flask. While stirring, the mixture is heated in an oil bath for about 4.5 h, whereby the temperature is gradually raised from an initial 30° C. to 105° C. After cooling, the product monobrominated heterodiamondoid dissolved in excess bromine is taken up with 100 mL carbon tetrachloride and poured into 300 mL ice water. The excess bromine is then removed with sodium hydrogen sulfide while cooling with ice water. After the organic phase has been separated, the aqueous solution is extracted once more with carbon tetrachloride. The combined extracts are washed three times with water. After the organic phase has been dried with calcium chloride, the solvent is distilled off and the last residues are removed under vacuum. The residue is dissolved in a small amount of methanol and crystallized in a cold bath. Further purification of the crystals is carried out by sublimation under vacuum.
Example 13
Dibromination of Heterodiamondoids Without Catalysts
[0205] As shown in FIG. 13 , a heterodiamondoid (37 mmol) is heated to 150° C. for about 22 h with anhydrous bromine (0.37 mol) in a pressure vessel. Usual work-up and recrystallization of the reaction product from methanol is performed as described above. The crystals are sublimated in vacuum. The sublimate is recrystallized several times from a very small amount of n-hexane affording a dibrominated derivative.
Example 14
Brominated Heterodiamondoids from Hydroxylated Compounds (FIG. 13 )
[0206] A mixture of a suitable hydroxylated heterodiamondoid and excess 48% hydrobromic acid is heated to reflux for a few hours (which can be conveniently monitored by GC analysis), cooled, and extracted with ethyl ether. The extract is combined and washed with aqueous 5% sodium hydroxide and water, and dried. Evaporation and normal column chromatography on alumina eluting with light to petroleum ether, hexane, or cyclohexane or their mixtures with ethyl ether affords the bromide with reasonable high yields.
Example 15
G-CH 2 CH 2 —Br from G-Br
[0207] A solution of a suitable monobrominated heterodiamondoid G-Br (0.046 mole) in 15 mL n-hexane in a 150-mL three-necked flask equipped with a stirrer, a gas inlet tube and a gas discharge tube with a bubble counter is cooled to −20 to −25° C. in a cooling bath. While stirring one introduces 4.0 g powdered freshly pulverized aluminum bromide of high quality, and ethylene is conducted in such a way that the gas intake can be controlled with the bubble counter. The reaction starts with a slight darkening of the color and is completed after about 1 h. The reaction solution is decanted from the catalyst into a mixture of ether and water. The ether layer is separated off, and the aqueous phase is extracted once more with ether. The combined ether extracts are washed with water and dilute sodium carbonate aqueous solution. After they have been dried over calcium chloride, the solvent is distilled off. Recrystallizing from methanol affords the pure heterodiamondoid ethyl bromide G-CH 2 CH 2 —Br.
Example 16
G-CH═CH—Br from G-Br
[0208] Step 1: in a 150-mL two-necked flask with a stirrer and a drying tube, a mixture of 0.069 mole of a suitable monobromonated heterodiamondoid G-Br and 20 mL vinyl bromide is cooled to −65° C. in a cooling bath. While stirring, 4.5 g powdered aluminum bromide is added in portions and the mixture is stirred for an additional about 3 hours at the same temperature. Then the reaction mixture is poured into a mixture of 30 mL water and 30 mL ethyl ether. After vigorously stirring, the ether layer is separated and the aqueous layer is extracted once more with ether. The combined ether extracts are washed with water and dilute sodium carbonate solution. After it has been dried with calcium chloride and the solvent has been distilled off, the residue is distilled under vacuum.
[0209] Step 2: a solution of 0.7 g fine powdered potassium hydroxide and the above compound (0.012 mole) in 10 mL diethylene glycol is heated to 220° C. in the oil bath for 6 hours. After cooling down the mixture is diluted with 30 mL water and exacted with ethyl ether. The ether extract is washed twice with water and dried over calcium chloride. The residue left behind after the ether has been distilled off is sublimated in vacuum, and if necessary, the compound can be recrystallized from methanol.
[0210] G-C≡C—Br can also be formed from G-Br using this method and appropriate starting materials.
Example 17
G-C 6 H 4 —Br from G-Br
[0211] 1.1 g sublimated iron(III) chloride and high pure C 6 H 5 Br (excess) are placed in a 150-mL three-necked flask, which is equipped with a stirrer, a reflux condenser and a dropping funnel. While stirring and heating in the steam bath, a suitable monobrominated heterodiamondoid G-Br (0.018 mole) is slowly added to the above flask over about 30 minutes. The reaction mixture is heated for about an additional 3 hours until the production of hydrogen bromide drops off. The mixture is kept standing over night and poured onto a mixture of ice and hydrochloric acid. The organic phase is separated out and the aqueous solution is extracted twice with benzene. The combined benzene extracts are washed several times with water and dried with calcium chloride. The residue solidifies upon cooling and is completely free of the solvent in vacuum. Recrystallization from a small amount of methanol while cooling with CO 2 /trichloroethylene and further sublimation under vacuum afford a pure product.
Example 18
Monochlorination of Heterodiamondoids
[0212] A solution of 0.074 mole of a heterodiamondoid and 10 mL (8.5 g, 0.092 mole) of tert-butyl chloride in 40 mL of anhydrous cyclohexane is prepared in a 0.1 L, three-necked, round-bottom flask fitted with a thermometer, a stirrer, and a gas exhaust tube leading to a bubbler submerged in water. The catalyst, aluminum chloride (total 0.46 g, 0.006 mole) is added in batches of 0.05 g at regular intervals over a period of about 8 hours. Progress of the reaction is followed conveniently by the rate of escaping isobutane gas. Upon completion of the reaction, 10 mL of 1.0 N hydrochloride acid solution is added with vigorous stirring, followed by 50 mL of ethyl ether. The organic layer is separated, washed with 10 mL of cold water and 10 mL of a 5% sodium bicarbonate solution, and dried over anhydrous calcium chloride. After removal of the solvents under reduced pressure, the crude product is obtained. GC analysis of this material reveals a composition of mainly monochlorinated heterodiamondoid with a small amount of unreacted heterodiamondoid. If necessary, recrystallization of a sample of this material from ethanol at −50° C. affords a pure monochlorinated heterodiamondoid.
Example 19
Monohydroxylation of Heterodiamondoids
[0213] A solution of 11.0 mmol of a heterodiamondoid in 18.7 g of methylene chloride is mixed with 4.22 g of a solution of 1.03 g (13.5 mmol) of peracetic acid in ethyl acetate. While being stirred vigorously, the solution is irradiated with a 100-watt UV light placed in an immersion well in the center of the solution. Gas evolution is evident from the start. The temperature is maintained at 40-45° C. for an about 21-hour irradiation period. At the end of this time, about 95% of the peracid had been consumed. The solution is concentrated to near dryness, treated twice in succession with 100-mL portions of toluene and reevaporated to dryness. Final drying in a desiccator affords a white solid. A portion of the above material is dissolved in a minimum amount of benzene-light petroleum ether. This solution is then subjected to chromatography on alumina in the usual manner eluting with firstly 1:1 benzene/light petroleum ether, followed by a mixture of methanol and ethyl ether to collect the unreacted heterodiamondoid, and the hydroxylated heterodiamondoid isomers, respectively. Further separation of the isomers can be achieved by using HPLC technique.
Example 20
Polyhydroxylation of Heterodiamondoids
[0214] Into a 4-neck flask immersed in a cooling bath and equipped with a low temperature condenser (−20° C.), and an air driven, well sealed mechanical stirrer, a solid addition funnel and a thermocouple, is added 0.037 mole of a heterodiamondoid, 150 mL methylene chloride, 200 mL double distilled water, 192 grams sodium bicarbonate and 300 mL t-butanol. The mixture is stirred and cooled to 0° C. and 200 grams 1,1,1-trifluoro-2-propanone (TFP) are added. The mixture is stirred and cooled down to −8° C. 200 grams oxone are added from the solid addition funnel over the course of 3 hours. The reaction mixture is stirred at 0° C. overnight (16 hours). The TFP is recovered by distillation (heating pot to 40° C. and condensing TFP in a receiver immersed in dry ice/acetone). The remainder mixture is filtered by suction and a clear solution is obtained. The solution is rotavapped to dryness, providing a mixture of polyhydroxylated heterodiamondoids that are purified by chromatography and/or recrystallization.
Example 21
Monohydroxylated Heterodiamondoids from Monobrominated Compounds (FIG. 15 )
[0215] A suitable monobrominated heterodiamondoid (0.066 mol) is heated to reflux for about 1 h in a round bottom flask, which is equipped with a stirrer and a reflux condenser, while stirring and adding 35 mL water, 3.5 mL tetrahydrofuran, 2.0 g potassium carbonate and 1.3 g silver nitrate. After cooling, the reaction product, which has crystallized out, is separated out and is extracted with tetrahydrofuran. The extract is diluted with water and the precipitate is suctioned off, dried and purified by sublimation under vacuum.
Example 22
G-CH 2 CH 2 —OH from G-CH 2 CH 2 Br (FIG. 15 )
[0216] A suitable G-CH 2 CH 2 —Br (0.066 mol) is heated to reflux for about 1 h in a round bottom flask, which is equipped with a stirrer and a reflux condenser, while stirring and adding 35 mL water, 3.5 mL tetrahydrofuran, 2.0 g potassium carbonate and 1.3 g silver nitrate. After cooling, the reaction product is separated out and is extracted with chloroform. Evaporating the solvent affords the product after purification by column chromatography.
Example 23
C-2 G-OH from G=O (FIG. 15 )
[0217] A suitable hetero diamondoidone G=O is reduced with lithium aluminum hydride (a little excess) in ethyl ether at low temperatures. After completion of the reaction, the reaction mixture is worked up by adding saturated Na 2 SO 4 aqueous solution to decompose excess hydride at low temperature. Decantation from the precipitated salts gives a dry ether solution, which, when evaporated, affords a crude C-2 monohydroxylated heterodiamondoid substituted at the secondary carbon, i.e. C-2 G-OH. Further recrystallization from cyclohexane gives an analytically pure sample.
Example 24
Diesterified Heterodiamondoids from Dihydroxylated Compounds
[0218] To 2 mL of dioxane is added a dihydroxylated heterodiamondoid (1.0 mmol) and triethylamine (2.2 mmol) at a temperature of 50° C. The resultant mixture is added dropwise to a solution of acrylic acid chloride (2.2 mmol) in dioxane (2 mL). The mixture is maintained at 50° C. for about 1 hour. The product is analyzed by GC. When the analysis confirms the formation of the desired diacrylate, the compound is isolated using standard methods.
Example 25
Oxidation of Heterodiamondoids to Heterodiamondoidones
[0219] A solution of 11.0 mmol of a suitable heterodiamondoid in 18.7 g of methylene chloride is mixed with 4.22 g of a solution of 1.03 g (13.5 mmol) of peracetic acid in ethyl acetate. While being stirred vigorously, the solution is irradiated with a 100-watt UV light placed in an immersion well in the center of the solution. Gas evolution is evident from the start. The temperature is maintained at 40-45° C. for an about 21-hour irradiation period. At the end of this time, about 95% of the peracid had been consumed. The solution is concentrated to near dryness, treated twice in succession with 100-mL portions of toluene and reevaporated to dryness. Final drying in a desiccator affords a crude white solid.
[0220] The crude hydroxylated heterodiamondoid mixture is then partially dissolved in acetone. The oxygenated components go into the solution but not all of the unreacted heterodiamondoid. Chromic acid-sulfuric acid solution is added dropwise until an excess is present, and the reaction mixture is stirred overnight. The acetone solution is decanted from the precipitated chromic sulfate and the unreacted heterodiamondoid, and is dried with sodium sulfate. The unreacted heterodiamondoid is recovered by dissolving the chromium salts in water and filtering. Evaporation of the acetone solution affords a white solid. This crude solid is chromatographed on alumina with standard procedures eluting first with 1:1 (v/v) benzene/light petroleum ether followed by ethyl ether or a mixture of ethyl ether and methanol (95:5 v/v) to collect the unreacted heterodiamondoid and the heterodiamondoidone, respectively. Further purification by recrystallization from cyclohexane affords a pure heterodiamondoidone.
Example 26
2,2-Bis(4-hydroxyphenyl) Heterodiamondoids from Keto Compounds
[0221] A flask is charged with a mixture of a heterodiamondoidone (0.026 mole), phenol (16.4 g, 0.17 mole), and butanethiol (0.15 mL). Heat is applied and when the reaction mixture becomes liquid at about 58° C., anhydrous hydrogen chloride is introduced until the solution becomes saturated. Stirring is continued at about 60° C. for several hours, during which period a white solid begins to separate out from the reddish-orange reaction mixture. The solid obtained is filtered off, washed with dichloromethane and dried to afford the bisphenol heterodiamondoid product. It is purified by sublimation after recrystallization from toluene.
Example 27
2,2-Bis(4-aminophenyl) Heterodiamondoids from Keto Compounds
[0222] To a solution of a heterodiamondoidone (0.041 mole) in 15 mL of 35% HCl aqueous solution in a 100 mL autoclave equipped with a stirrer is added excess aniline (15.7 g, 0.17 mole) and the mixture is stirred at about 120° C. for about 20 hours. After cooling, the solution is made basic with NaOH aqueous solution to pH 10 and the oily layer is separated and distilled to remove the unreacted excess aniline. The residual crude product is recrystallized from benzene.
Example 28
2,2-Bis[4-(4-aminophenoxy)phenyl]Heterodiamondoids from Bisphenol Heterodiamondoids
[0223] A mixture of a 2,2-bis(4-hydroxyphenyl) heterodiamondoid (0.01 mole), p-fluoronitrobenzene (3.1 g, 0.022 mole), potassium carbonate (3.31 g, 0.024 mole) and N,N,-dimethylacetamide (DMAc, 10 mL) is refluxed for about 8 hours. The mixture is then cooled and poured into a ethanol/water mixture (1:1 by volume). The crude product is crystallized from DMF to provide yellow needles of the 2,2-bis[4-(4-nitrophenoxy)phenyl]heterodiamondoid.
[0224] Hydrazine monohydrate (20 mL) is added dropwise to a mixture of the above product (0.002 mole), ethanol (60 mL), and a catalytic amount of 10% palladium on activated carbon (Pd/C, 0.05 g) at the boiling temperature. The reaction mixture is refluxed for about 24 hours, and the product 2,2-Bis[4-(4-aminophenoxy)phenyl]heterodiamondoid is precipitated during this period. The mixture is then added to enough ethanol to dissolve the product and filtered to remove Pd/C. After cooling, the precipitated crystals are isolated by filtration and recrystallized from 1,2-dichlorobenzene.
Example 29
Mononitration of Heterodiamondoids
[0225] A mixture of 0.05 mole of a heterodiamondoid and 50 mL of glacial acetic acid is charged to a stirred stainless 100 mL autoclave which is pressurized with nitrogen to a total pressure of 500 p.s.i.ga. After the mixture is then heated to 140° C., 9.0 g (0.1 mole) of concentrated nitric acid is introduced into the reaction zone by means of a feed pump at a rate of 1-2 mL per minute. When the acid feed is completed, the reaction temperature is maintained at 140° C. for 15 minutes, after which time the reaction mixture is cooled down to room temperature and diluted with an excess of water to precipitate the products. The filtered solids are slurried with a mixture of 10 mL of methanol, 15 mL of water, and 1.7 g of potassium hydroxide for 18 hours at room temperature. After dilution with water, the alkali-insoluble material is extracted by light petroleum ether. The petroleum ether extracts are washed by water and dried over anhydrous magnesium sulfate. Concentration of this solution affords a white solid. The aqueous alkali solution from which the alkali-insoluble material had been extracted is cooled to 0-3° C. and neutralized by the dropwise addition of an aqueous acetic acid-urea mixture to regenerate some more products. GC analysis shows that the alkali-insoluble sample is mainly mononitro heterodiamondoid.
Example 30
Monocarboxylation of Heterodiamondoids
[0226] A mixture of 29.6 g (0.4 mole) tert-butanol and 55 g (1.2 mole) 99% formic acid is added dropwise over about 3 hours to a mixture of 470 g 96% sulfuric acid and 0.1 mole heterodiamondoid dissolved in 100 mL cyclohexane while stirring vigorously at room temperature. After decomposing with ice, the acids are isolated and purified by recrystallization from methanol/water giving the monocarboxylated heterodiamondoid.
Example 31
G-CHClCOOH from G-Br
[0227] A mixture of a suitable monobrominated heterodiamondoid G-Br (0.012 mole) and 9.0 g trichloroethylene CHCl═CCl 2 is added dropwise in the course of about 4 hours into 24 mL 90% sulfuric acid at 103-106° C. while stirring. After the addition is completed, the mixture is stirred for about an additional 2 hours at the specified temperature, then cooled down and hydrolyzed with ground ice. The precipitated product can be freed from the neutral fraction by dissolution in dilute sodium hydroxide solution and extraction with ethyl ether. When acidified with dilute hydrochloric acid solution, the carboxylic acid precipitates out of the alkaline solution.
Example 32
G-NHCOCH 3 from G-Br
[0228] A suitable monobrominated heterodiamondoid G-Br (0.093 mole) is dissolved in 150 mL acetonitrile. While stirring, 30 mL concentrated sulfuric acid is slowly added to the above solution, whereby the mixture heats up. After it has been left standing for about 12 hours, the solution is poured into 500 mL ice water, whereby the monoacetamino heterodiamondoid separates out in high purity.
Example 33
G-NHCHO from G-COOH
[0229] Within 7 minutes 8.16 g (0.17 mole) sodium cyanide and a suitable monocarboxylated heterodiamondoid G-COOH (0.028 mole) are added to 100 mL 100% sulfuric acid while stirring vigorously. After ½ hour, decomposition is carried out by pouring the reaction mixture onto 250 g crushed ice which is then made basic by the addition of a sufficient amount of odium hydroxide solution and extracted five times with benzene/ether. The solvent is removed in vacuo from the combined extracts and the residue is recrystallized from benzene/hexane.
Example 34
G-CO 2 CH 2 CH 3 from G-COOH via G-COCl
[0230] 0.017 mole of a suitable monocarboxylated heterodiamondoid G-COOH is mixed with 4.2 g PCl S in a 50-mL flask with a stirrer and a reflux condenser. The reaction starts after 30-60 seconds with liquefaction of the reaction mixture. The mixture is heated for an additional about 1 hour while stirring on the steam bath. The POCl 3 formed is distilled off under vacuum. The acid chloride left behind as a residue is cooled with ice water, and 6.0 mL absolute ethanol is added dropwise. The mixture is heated for an additional around 1 hour on the steam bath and then poured into 50 mL water after it has been cooled down. The ester is taken up with ethyl ether and then washed with potassium carbonate aqueous solution and water. After drying, fractionation is carried out over calcium chloride under vacuum.
Example 35
G-CH═CH 2 from G-Br
[0231] Step 1: a solution of a suitable monobrominated heterodiamondoid G-Br (0.046 mole) in 15 mL n-hexane in a 150-mL three-necked flask equipped with a stirrer, a gas inlet tube and a gas discharge tube with a bubble counter is cooled to −20 to −25° C. in a cooling bath. While stirring one introduces 4.0 g powdered freshly pulverized aluminum bromide of high quality, and ethylene is conducted in such a way that the gas intake can be controlled with the bubble counter. The reaction is completed after about 1 h. The reaction solution is decanted from the catalyst into a mixture of ether and water. The ether layer is separated off, and the aqueous phase is extracted once more with ether. The combined ether extracts are washed with water and dilute sodium carbonate aqueous solution. After they have been dried over calcium chloride, the ether is distilled off. The residue is separated by distillation under vacuum. Recrystallizing from methanol affords crystals of the heterodiamondoidyl ethyl bromide G-CH 2 CH 2 Br.
[0232] Step 2: a solution of 0.7 g fine powdered potassium hydroxide and the above heterodiamondoidyl ethyl bromide G-CH 2 CH 2 Br (0.012 mole) in 10 mL diethylene glycol is heated to 220° C. in the oil bath for 6 hours. After cooling down the mixture is diluted with 30 mL water and exacted with ethyl ether. The ether extract is washed twice with water and dried over calcium chloride. The residue left behind after the ether has been distilled off is sublimated in vacuum, and if necessary, the compound can be recrystallized from methanol.
Example 36
G-C≡CH from G-Br
[0233] Step 1: in a 150-mL two-necked flask with a stirrer and a drying tube, a mixture of 0.069 mole of a suitable monobromonated heterodiamondoid and 20 mL vinyl bromide is cooled to −65° C. in a cooling bath. While stirring, 4.5 g powdered aluminum bromide is added in portions and the mixture is stirred for an additional about 3 hours at the same temperature. Then the reaction mixture is poured into a mixture of 30 mL water and 30 mL ethyl ether. After vigorously stirring, the ether layer is separated and the aqueous layer is extracted once more with ether. The combined ether extracts are washed with water and dilute sodium carbonate solution. After it has been dried with calcium chloride and the solvent has been distilled off, the residue is distilled under vacuum.
[0234] Step 2: 15 g powdered potassium hydroxide in 30 mL diethylene glycol is heated to reflux with 0.046 mole of the above product for about 9 hours in the oil bath. Compound monoethynylated heterodiamondoid which is formed is then sublimated in the condenser and must be returned to the reaction mixture from time to time. At the end of the reaction time, the reaction mixture is distilled until no more solid particles go over. The distillate is extracted with ethyl ether and the ether phase is washed with water and dried over calcium chloride. A short time after the ether has been distilled off, the residue solidifies. It is sublimated under vacuum and, if necessary, recrystallized from methanol.
Example 37
G-O—CH 2 —C 6 H 5 from G-Br
[0235] To a solution of benzyl alcohol C 6 H 5 —CH 2 —OH (0.28 mole) containing 0.03 mole of sodium benzylate is added 0.01 mole of G-Br and the resulting mixture heated for about 4 hours, during which a copious precipitate NaBr formed. After cooling, the reaction mixture is poured into water and the aqueous phase extracted with ethyl ether and the later dried over sodium sulfate, then evaporated. Most of the benzyl alcohol is removed by distillation, leaving ca. 4 mL of oil which is chromatographed over alumina Elution with petroleum ether afford the product.
Example 38
[0236] Heterodiamondoidyl acetic acid, e.g. G-COOH is prepared as shown in Example 29. The corresponding acid chloride G-COCl is obtained by stirring a mixture of the acid and thioyl chloride diluted with petroleum ether at room temperature for about 50 hours. Treatment of the acid chloride G-COCl with an excess amount of ethereal diazomethane gives the heterodiamondoidyl acetyl diazomethane G-COCHN 2 . Reactions of the acid chloride G-COCl with such amines as ammonia and aniline give the corresponding amides, in those cases G-CONH 2 and G-CONHC 6 H 5 respectively.
Example 39
G-CONH 2 from G-COCl
[0237] Concentrated aqueous ammonia (11.0 mL) is, over a period of 30 min., stirred, drop by drop, into a stirred solution of G-COCl, prepared from 5.5 mmole of G-COOH, in 4.0 mL of dry THF under cooling with ice-water. The stirring is continued for about 6 hours, and then, the precipitates are filtered out. The addition of water to the filtrate gives the second crop. The combined precipitates are washed with water and dried to give the title compound.
Example 40
Hofmann Reaction of G-CONH 2
[0238] Into an ice-cooled bromine-alkali reagent, freshly prepared from 1.0 g of bromine, 1.0 g of sodium hydroxide, and 10 mL of water, 0.5 g of G-CONH 2 is added and stirred. The temperature is then slowly raised to about 80° C. over a 3.5 hour period and kept there for about 10 min. After cooling, the separated solids are filtered and washed with water. Recrystallization from chloroform-petroleum ether gives the pure product G-NHCONHC(O)-G.
Example 41
G-N 3 from G-Br
[0239] A mixture of G-Br (2 mmole) and sodium azide (1.3 g) in dry dimethyl sulfoxide (DMF, 20 mL) is heated with stirring at 100° C. for about two days. The mixture is poured onto ice-water to give precipitates which can be purified by recrystallization from aqueous methanol to give the pure product.
Example 42
G-OCOCl from G-OH
[0240] To a solution of liquid phosgene (COCl 2 , 30 g) in anhydrous benzene (100 mL), a solution of G-OH (53 mmoles) and pyridine (7 g) in benzene (200 mL) is added dropwise and with stirring over a 1 hour period, while maintaining the reaction temperature at about 4° C. when solids precipitate, additional benzene is added.
[0241] The reaction mixture is filtered and the filtrate is poured into ice water and shaken in a separatory funnel. The organic layer is dried with sodium sulfate and concentrated to about one-fifth of its original volume under reduced pressure at room temperature, and the concentrated solution is stored in a freezer. The yield may be considered essentially quantitative for the purpose of synthetic use of the solution.
[0242] When a sample of the concentrate is evaporated to dryness at room temperature, the solid is obtained. Recrystallization from anhydrous petroleum ether at low temperature, e.g. −20° C., may give crystals of the product.
Example 43
G-OCONHNH 2 from G-OCOCl and H 2 NNH 2
[0243] A solution of G-OCOCl (9.3 mmoles) in anhydrous benzene (150 mL) is added slowly to a stirred solution of anhydrous hydrazine (2.5 g) in t-butyl alcohol (20 mL). After stirring for about 2 hours, the solvent is removed in vacuo. The residue is dissolved in a mixture of ether (150 mL) and water (10 mL). The ether layer is washed with 35 mL portions of water, 5 mL of 1% sodium carbonate solution, and 5 mL of water, and dried. Anhydrous hexane (10 mL) is added and the solution is concentrated to about 10 mL. Cooling the solution at about ±10° C. gives the product G-OCONHNH 2 .
Example 44
Heterodiamondoidyloxycarbonyl Amino Acids from G-OCOCl and Amino Acids
[0244] A suitable amino acid (5 mmoles) is suspended in water (about 20 mL). The mixture is stirred and cooled in an ice bath. Sodium hydroxide (1N, 5 mL) is added whereupon the amino acid usually dissolved. To this mixture, 0.8 g sodium carbonate (7.5 mmoles) is added. From a solution of G-OCOCl, the solvent is removed in vacuo on a flash evaporator at a bath temperature of about 30° C. (the concentration of the chloroformate in the benzene solution is determined by removing the solvent from an aliquot in vacuo at about 30° C. and weighting the residue). To the residue which may be oily or semisolid, dry petroleum ether is added and removed in vacuo. This is repeated once more to remove traces of phosgene which may be left in the preparation of the chloroformate. The residue is dissolved in anhydrous dioxane (5 mL) and added in about four portions to the solution of the amino acid over a period of about 1 hour with continued stirring and cooling. If solid precipitates, ether is added (5 mL) after the first and last addition of the chloroformate. After the addition of the chloroformate, the container of the chloroformate is washed twice with a small amount of dioxane. After stirring in ice for about 2 hours, the solution is extracted three times with ether or ethyl acetate, and under stirring and cooling acidified with 85% phosphoric acid or 10% sulfuric acid to a pH of about 2. The precipitated product is extracted into the organic layer and the aqueous phase is extracted with two more portions of fresh organic solvent. The combined extracts are dried over sodium sulfate and the solvent is removed in vacuo. The residue is recrystallized from a suitable solvent, e.g. ether-petroleum ether, ethyl acetate or ethyl acetate-petroleum ether.
Example 45
G-POCl 2 from G-Br (FIG. 21 )
[0245] 0.1 mole of G-Br, 40 g (0.15 mol) of AlBr 3 and 200 mL of PCl 3 are heated for about 5 hours under reflux while being stirred. After cooling down and filtration, the residue is washed with 100 mL of benzene, suspended in 300 mL of CCl 4 and decomposed carefully with water while cooling with ice. The organic phase is separated out, washed with water, dried over CaCl 2 and concentrated in vacuum. Separation and purification of the product G-POCl 2 can be conducted by distilling the residue and recrystallization from acetone. Please note that G-POCl 2 does not reaction with ethanol in pyridine or piperidine in benzene. Thus, 0.05 mole of G-POCl 2 together with 9.2 g (0.2 mole) ethanol and 7.9 g (0.1 mole) pyridine are heated under reflux for about 3 hours. Then the reaction mixture is poured onto ice while adding dilute hydrochloric acid. The product is filtered off and recrystallized from acetone affording the unreacted G-POCl 2 . In addition, 0.05 mole of G-POCl 2 and 17 g (0.2 mole) of piperidine are dissolved in 200 mL absolute benzene, and then heated for about 48 hours under reflux while stirring. After filtration, the filtrate is concentrated to dryness affording the unreacted G-POCl 2 .
[0246] 20 mmoles of G-POCl 2 is heated for about 6 hours with 100 mL water under reflux. The aqueous solution is filtered after cooling, and the residue is recrystallized from glacial acetic acid affording the product G-PO(OH) 2 .
[0247] Under nitrogen a solution of 0.1 mole of G-POCl 2 in 150 mL absolute ether is added dropwise over a period of about 2 hours to a suspension of 7 g LiAlH 4 in 400 mL absolute ether. After the addition, the mixture is stirred for an additional 1 hour under reflux. The excess LiAlH 4 is destroyed by adding about 200 mL dilute hydrochloric acid. The organic phase is separated out, washed with water, dried over MgSO 4 and concentrated under nitrogen. The residue is fractionated under nitrogen in vacuum to give the product G-PH 2 .
[0248] About 50 mmoles of G-PH 2 is heated carefully at approximately 50° C. with 50 mL of 30% hydrogen peroxide (H 2 O 2 ) until the reaction starts. Then the reaction mixture is diluted to one and half with water, boiled briefly and filtered in hot. After cooling down it is possible to isolate some of the product G-P(OH) 2 . The residue is extracted with CHCl 3 and then recrystallized from glacial acetic acid to give some additional amount of the product.
[0249] 0.05 mole of G-P(OH) 2 is added in small portions to 75 mL of PCl 3 within 10 minutes. After the addition, the reaction mixture is stirred for an additional 5 minutes. The phosphoric acid produced is separated out and the residue is concentrated under vacuum and distilled to give the product G-PCl 2 . Purification can be carried out by sublimating several times to give a pure sample for analysis.
[0250] 0.01 mole of G-PCl 2 is stirred in 50 mL water intensively for about 10 hours at room temperature. Then the mixture is filtered and the residue is recrystallized several times from acetonitrile to yield the product G-P(OH) 2 .
Example 46
G-SOCl from G and Subsequent Reactions (FIG. 22 )
[0251] 40 g (0.3 mole) of AlCl 3 and 200 mL of SOCl 2 are reacted at about −15° C. for about 2 hours with 0.3 mole of a heterodiamondoid. The mixture is stirred for an additional 1 hour at this temperature. Then the clear solution is allowed to warm to room temperature, and the excess SOCl 2 is removed under vacuum. The residue is taken up in 300 mL of CCl 4 and carefully decomposed with water. The organic phase is separated out, washed with water, dried over CaCl 2 and concentrated in vacuum. The residue is distilled to give the product G-SOCl. Please note that G-Cl is produced as the major by-product.
[0252] 0.1 mole of G-SOCl is heated under reflux for about 6 hours with 200 mL of absolute methanol. The solvent is then removed in vacuum and the residue is distilled to give the product. Further purification can be carried out by sublimation under vacuum.
[0253] 0.1 mole of LiAlH 4 is suspended in 100 mL of absolute ether and heated under reflux for about 1 hour. Then a solution of 0.02 mole of G-SO 2 CH 3 in 100 mL of absolute ether is added dropwise over a period of about 2 hours. After about additional 17 hours of stirring under reflux, the excess LiAlH 4 is decomposed with a saturated Na 2 SO 4 solution, and the ether phase is separated out after 100 mL of concentrated hydrochloric acid has been added. The aqueous phase is washed for an additional two times with ether. The extracts are combined and dried over CaCl 2 and concentrated under vacuum. The residue is sublimated to give G-SH.
[0254] To 650 mL 5% sodium hydroxide solution is added about 0.25 mole of G-SOCl (crude product) at room temperature. After about 5 hours of intense stirring, the temperature is increased slowly to about 50° C., then filtration. Approximately 12% chlorination products remain as residue. The filtrate is acidified with concentrated hydrochloric acid while cooling with ice, and extracted several times with ether. The combined extracts are washed with water, dried over MgSO 4 and concentrated to a dry product. Recrystallization from acetonitrile gives a pure product G-SO 2 H.
[0255] 5 mmoles of G-SO 2 H is suspended in 25 mL water while adding 1 mL 30% hydrogen peroxide. Then the mixture is heated while stirring on a water bath and an additional 3 mL 30% hydrogen peroxide are added dropwise within 30 minutes. The solution is briefly boiled, filtered and concentrated under vacuum to dryness at about 30° C. to give the heterodiamondoidyl sulfonic acid monohydrate G-SO 3 H H 2 O.
[0256] 0.1 mole of G-SH dissolved in 100 mL ethanol is added while stirring into a solution of 8 g (0.2 mole) of NaOH in 200 mL water and treated for about 1 hour at 50° C. with 15.4 g (0.1 mole) of diethylsulfate. After an additional 1 hour stirring under reflux, the reaction mixture is cooled down and extracted several times with ether. The combined extracts are concentrated in vacuum and the residue is distilled over CaCl 2 to give the product G-SC 2 H 5 .
[0257] 0.05 mole of G-SC 2 H 5 in 100 mL glacial acetic acid is heated to reflux with 17.5 g (0.15 mole) 30% hydrogen peroxide. After about 1 hour of stirring under reflux, the reaction mixture is poured onto ice and filtered. Recrystallization from ethanol/water gives the product G-SO 2 C 2 H 5 .
[0258] 0.02 mole of G-SO 2 C 2 H 5 and 12 g KOH are heated to 250° C. with 3-5 drops of water. Then the temperature is raised to 275° C. in the course of about 45 minutes, whereby a strong development of a gas takes place. After cooling down, the mixture is dissolved in a little water, acidified with concentrated hydrochloric acid while cooling with ice and extracted several times with ether. The distillation residue from the ether extract gives, after recrystallization from acetonitrile, a pure product of G-SO 2 H.
[0259] 0.05 mole of G-SO 2 H is left standing over night with 100 mL freshly distilled SOCl 2 at room temperature. The excess SOCl 2 is carefully removed under vacuum, and the residue is distilled, whereby the product G-SOCl solidifies in the receiver.
[0260] 0.1 mole of G-SOCl together with 200-300 mL absolute alcohol and 7.9 g (0.1 mole) pyridine is heated for 8-12 h under reflux. The excess alcohol is then removed under vacuum and the residue is mixed with ether. The ether solution is washed twice with dilute hydrochloric acid and water, dried over MgSO 4 and concentrated. The residue is distilled to give the corresponding ester.
[0261] 45 mmoles of G-SOCl is heated with 300 mL 25% aqueous ammonia or 150 mL 40% aqueous dimethylamine for about 2 hours while stirring under reflux. Then the reaction mixture is concentrated to dryness in vacuum and the residue is extracted with ether. The distillation residue from the ether extract is recrystallized from cyclohexane to afford the corresponding amide.
[0262] Into a clear solution of 0.05 mole G-SO 2 H and 2 g (0.05 mole) NaOH in 200 mL water is introduced a strong chlorine gas flow at approximately 5° C. temperature increase within 45 minutes. After filtration, the residue is extracted in ether. The ether solution is washed chlorine-free with NaHSO 3 solution, dried over MgSO 4 and concentrated to dryness in vacuum at room temperature. Recrystallization from ethanol gives the product G-SO 2 Cl. Further recrystallization several times from petroleum ether can afford a pure sample for analysis.
[0263] 0.01 mole G-SO 2 Cl in 100 mL absolute ether is added dropwise within 1 hour to a suspension of 3 g LiAlH 4 in 100 mL absolute ether. After the addition, the reaction mixture is stirred for about 3 hours under reflux, then the excess LiAlH 4 is destroyed with dilute hydrochloric acid. The organic phase is separated out, dried over MgSO 4 and concentrated. The residue is sublimated several times to give G-SH.
[0264] 10 mmoles G-SO 2 Cl and 100 mL 10% sodium hydroxide solution are heated on a water bath for about 4 hours while adding 1 g pyridine. After cooling and filtration, the filtrate is acidified with concentrated hydrochloric acid and perforated over night with ether. The ether extract is dried over MgSO 4 and concentrated to yield G-SO 2 H.
[0265] 20 mmoles G-SO 2 Cl together with 30 mL absolute methanol and 3 g pyridine is heated for about 4 hours at 50° C. while stirring vigorously. Then the reaction mixture is poured on ice and extracted with ether. The ether solution is washed with dilute hydrochloric acid, dried over MgSO 4 and concentrated. The residue is sublimated to give G-Cl.
[0266] 10 mmoles G-SO 2 Cl and 100 mL 25% aqueous ammonia are heated on a water bath for about 3 hours while stirring. The solution is concentrated in vacuum to dryness, and the residue is sublimated to give G-OH.
[0267] 0.02 mole of the corresponding hetero diamondoidyl sulfinic acid ester or amide is treated in 150-400 mL acetone at reflux with a saturated solution of KMnO 4 in acetone until a violet color remains. After an additional 30 minutes of stirring under reflux, the reaction mixture is filtered from MnO 2 and the residue is extracted several times with acetone. The combined filtrates are then concentrated in vacuum to give the corresponding hetero diamondoidyl sulfonic acid esters or amides.
Example 47
G-G from G-Br
[0268] A monobrominated heterodiamondoid G-Br (50 mmole) is dissolved in 30 mL of xylene and heated to reflux in a three-necked flask fitted with thermometer, nitrogen inlet, stirrer, and reflux condenser, under a slow stream of nitrogen. Then a total of 1.15 g of small pieces of sodium metal is added to the stirred reaction mixture over a period of about 4 hours. After all sodium has been added, the mixture is refluxed for about an additional hour and then filtered in the hot state. On cooling to room temperature, the product G-G is crystallized from the filtrate. This G-G product can itself be di brominated and thereafter converted to dicyano, decarboxyl diamino and diacetamido derivatives as desired.
Example 48
CH 3 OC 6 H 4 -G-G-C 6 H 4 OCH 3 from Br-G-G-Br
[0269] To Br-G-G-Br (11.5 mmole) is added 25 mL of anisole and the mixture is heated to reflux (about 155° C. pot temperature) for about 5 hours. After about 15 minutes refluxing, hydrogen bromide is evolved. The evolution of hydrogen bromide is ceased after about 1 hour. The reaction product is filtered hot and on cooling to room temperature, a crude product is collected which is then recrystallized from xylene to give the pure product CH 3 OC 6 H 4 -G-G-C 6 H 4 OCH 3 .
Example 49
HClH 2 NCH 2 -G-G-CH 2 NH 2 HCl and H 2 NCH 2 -G-G-CH 2 NH 2 from NC-G-G-CN
[0270] Powdered lithium aluminum hydride (0.6 g) is charged into a three-neck flask fitted with a thermometer, nitrogen inlet, addition funnel, and reflux condenser together with 15 mL of anhydrous THF. A solution of NC-G-G-CN (7.8 mmole) in 20 mL of anhydrous THF is added over a period of about 20 min. the reaction product, after cooling to room temperature, is poured onto ice containing dilute hydrochloric acid. Recrystallization from dilute hydrochloric acid gives the dihydrochloride product HClH 2 NCH 2 -G-G-CH 2 NH 2 HCl. The free diamine H 2 NCH 2 -G-G-CH 2 NH 2 is obtained from the dihydrochloride by reaction with ammonia.
Design of Heterodiamondoid-Containing Polymers or Co-Polymers
[0271] Polymers such as polyamides, polyimides, polyesters, polycarbonates which are easily processed soluble, mechanically strong and thermally stable are very important materials in a wide range of industries, such as the microelectronics industry. Introduction of different pendant groups such as heterodiamondoid groups along the polymer backbone can impart greater solubility and enhanced rigidity as well as better mechanical and thermal properties of the resulting polymers. Of particular interest is introducing such heteroatom-containing cage hydrocarbons into the polymer chain because such cardo groups show significant characteristics such as high cardo/hydrogen ratio, high thermal and oxidative stability, rigidity, hydrophobicity, and transparency. They also can impart desired electrical and optical properties to the polymers.
Example 50
Polymerization of Diacrylated Heterdiamondoids
[0272] The following compositions are subjected to polymerization: diacrylated heterodiamondoid; monoacrylated heterodiamondoid; a 50:50 mixture by weight of monoacrylated heterodiamondoids and methyl methacrylate; and, a 50:50 mixture by weight of monoacrylated heterodiamondoid and diethylene glycol bis allylcarbonate. To the various compositions is added 0.1 part by weight of a photo-polymerization initiator (benzophenone). The mixture is applied to a glass plate and photo-polymerized by irradiation with ultraviolet light.
Example 51
Polymerization of Diethynylated Heterodiamondoids
[0273] A sample of a diethynylated heterodiamondoid (275 mg) is sealed in a glass tube and heated to 200° C. for 14 hours and at 250° C. for 48 hours. The tube is cooled to room temperature and opened to afford a polymeric resin.
Example 52
Polyesters Derived from 2,2-Bis(4-hydroxyphenyl) Heterodiamondoids by Solution Polycondensation
[0274] A 2,2-bis(4-hydroxyphenyl) heterodiamondoid (0.005 mole) is mixed with pyridine (2 mL) at room temperature for about 20 minutes. Terephthaloyl chloride (1.015 g, 0.005 mole) in nitrobenzene (20 mL) is added to the above solution at room temperature for about 5 minutes and then the mixture is heated to about 150° C. for about 10 hours. The resulting polymer solution is poured into methanol to precipitate the polymer. The polymer is washed with hot methanol, collected on a filter, and dried in vacuo at about 60° C. for about 24 hours.
Example 53
Polyamides Derived from 2,2-Bis[4-(4-aminophenoxy)phenyl]Heterodiamondoids by Solution Polycondensation
[0275] A flask is charged with a mixture of a 2,2-bis[4-(4-aminophenoxy)phenyl]heterodiamondoid (0.9 mmol), terephthalic acid (0.149 g, 0.9 mmol), triphenyl phosphite (0.7 mL), pyridine (0.6 mL), N-methyl-2-pyrrolidone (NMP, 2 mL) and calcium chloride (0.25 g). It is refluxed under argon for about 3 hours. After cooling, the reaction mixture is poured into a large amount of methanol with constant stirring, producing a precipitate that is washed thoroughly with methanol and hot water, collected on a filter, and dried to afford a polyamide containing heterodiamondoid components along the polymer chain.
Example 54
Polyimides Derived from 2,2-Bis[4-(4-aminophenoxy)phenyl]Heterodiamondoids by Chemical Imidization
[0276] To a stirred solution of a 2,2-bis[4-(4-aminophenoxy)phenyl]heterodiamondoid (1.2 mmol) in DMAc (7 mL) is gradually added pyromellitic dianhydride (0.262 g, 1.2 mmol). The mixture is stirred at room temperature for 2-4 hours under argon atmosphere to form the poly(amic acid). Imidization is carried out by adding DMAc and an equimolar mixture of acetic anhydride and pyridine into the above-mentioned poly(amic acid) solution with stirring at room temperature for about 1 hour and then heating at about 100° C. for an additional about 3 hours. The reaction product is subsequently poured into methanol and the precipitate is filtered off, washed with methanol and hot water, and dried to afford the polyimide containing heterodiamondoid components along the polymer chain.
Example 55
Polyimides Derived from 2,2-Bis(4-aminophenyl) Heterodiamondoids by Chemical Imidization
[0277] To a solution of a 2,2-bis(4-aminophenyl) heterodiamondoid (5 mmol) in 17.9 mL of NMP, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA, 98.6%, 1.61 g, 5 mmol) is added with a solid content of 15 wt %. The solution is continuously stirred at room temperature for about 24 hours. To the reaction mixture are added 1.5 mL of acetic anhydride and 2.0 mL of pyridine and then the temperature is raised to about 120° C. and kept at this temperature for about 3 hours. The resulting solution is poured into excess methanol and filtered. The precipitated polymer is washed several times with water and methanol, and then the polymer is dried at about 100° C. for around 12 hours in vacuo.
Example 56
Polyimides Derived from 2,2-Bis(4-aminophenyl) Heterodiamondoids by Solution Polymerization
[0278] To a solution of a 2,2-bis(4-aminophenyl) heterodiamondoid (5 mmol) in 19 mL of freshly distilled m-cresol, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (98.6%, 1.61 g, 5 mmol) and isoquinoline (0.95 mL) as a catalyst are added at room temperature under nitrogen atmosphere. The reaction mixture is heated to about 70˜80° C. over 2 hours and kept at this temperature for about 2 hours. Afterwards, the solution temperature is slowly raised to about 200° C. over 2 hours and refluxed for 6 hours. The polymerization is performed under a gentle nitrogen stream to remove the water produced during imidization. Work-up is done by pouring the resulting solution into excess methanol and filtering. The precipitated polymer is washed several times with water and methanol, and then the polymer is dried at about 100° C. for around 12 hours in vacuo.
Example 57
Linear Polyaspartimides Derived from 2,2-Bis[4-(4-aminophenoxy)phenyl]Heterodiamondoids by the Michael Addition Reaction
[0279] In a 100 mL three necked flask equipped with a magnetic stirrer, a reflux condenser, thermometer and nitrogen inlet, 0.553 g (1.25 mmol) of bis(3-ethyl-5-methyl-4-maleimidophenyl)methane (BEMM) is added to 3.5 mL of m-cresol. When all the BEMM is dissolved, 1.25 mmol of a diamine 2,2-bis[4-(4-aminophenoxy)phenyl]heterodiamondoid is added. Then 0.1 mL of glacial acetic acid, used as a catalyst, is added into the mixture so that the above diamine is completely dissolved. The reaction mixture is then immersed in an oil bath maintained at 100-110° C. for about 100 hours to polymerize. The resulting polymer is isolated by pouring the viscous reaction mixture into excess ethanol under vigorous stirring. The polymer precipitate is collected by filtration and washed thoroughly with ethanol and extracted with hot ethanol using a Soxhlet extractor and subsequently dried in a vacuum oven at 70° C. for about 24 hours.
Example 58
4-(1-Heterodiamondoidyl)-1,3-Benzenediols from Brominated Compounds and Subsequent Reactions
[0280] A suitable brominated heterodiamondoid (0.046 mole), resorcinol (5.51 g, 0.05 mole), and benzene (50 mL) are combined in a reaction flask equipped with a nitrogen inlet, a condenser fitted with a caustic scrubber, and a stirrer. This mixture is heated to reflux and for about 72 hours to allow for reaction under a constant nitrogen purge to assist in the removal of HBr formed. The reaction mixture is cooled to ambient temperature and the hetero diamondoidyl substituted resorcinol is crystallized from solution. Residual resorcinol is removed by precipitating a solution of the product in methanol into warm water followed by filtrating and washing with water. Subsequent purification to a polymerization quality monomer is accomplished by vacuum drying to remove residual water, recrystallizing from toluene, and finally subliming to afford the product which is used in the following reactions.
[0281] A mixture of a 4-(1-heterodiamondoidyl)-1,3-benzenediol (13 mmol), p-chloronitrobenzene (4.53 g, 28.8 mmol), potassium carbonate (4.3 g, 31.2 mmol) and dry N,N-dimethylformamide (DMF, 30 mL) is refluxed for about 8 hours. The mixture is then cooled and poured into a methanol-water solution (1:1 by volume). The crude product is recrystallized from glacial acetic acid.
[0282] Hydrazine monohydrate (10 mL) is added dropwise to a mixture of the above product (4-(1-heterodiamondoidyl)-1,3-bis(4-nitrophenoxy)benzene, 12.3 mmol), ethanol (25 mL), and a catalytic amount of 10% palladium on activated carbon (Pd/C, 0.05 g) at the boiling temperature. The reaction mixture is refluxed for about 24 hours, and the diamine product is precipitated during this period. The mixture is then added to a sufficient amount of ethanol to dissolve the diamine product and filtered to remove Pd/C. After cooling, the recipitated crystals are isolated by filtration and recrystallized from 1,2-dichlorobenzene to afford a pure diamine product.
[0283] A flask is charged with 1.73 mmol of a 4-(1-heterodiamondoidyl)-1,3-bis(4-aminophenoxy)benzene, 0.68 g (3.54 mmol) of trimellitic anhydride, and 5 mL of DMAc. The mixture is stirred at room temperature for about 5 hours under argon atmosphere. While continuing to maintain agitation and room temperature, 2.4 mL of acetic anhydride and 1.5 mL of pyridine are added incorporating for about 1 hour. Afterwards the mixture is heated at 100° C. for about 4 hours and then cooled and poured into methanol. The precipitate is filtered off and is purified by extraction with hot ethanol using a Soxhlet extractor and subsequently dried in a vacuum oven at 70° C. for 24 hours to afford diimide-dicarboxylic acid: 4-(1-hetero diamondoidyl)-1,3-bis(4-trimellitimidophenoxy)benzene.
[0284] A mixture of the diimide-dicarboxylic acid (4-(1-heterodiamondoidyl)-1,3-bis(4-trimellitimidophenoxy)benzene, 0.7 mmol), 0.362 g of a diamine (2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 0.7 mmol), 0.25 g of calcium chloride, 0.6 mL of triphenyl phosphite, 0.6 mL of pyridine, and 3.0 mL of NMP is heated with stirring at 100° C. for about 2 hours under argon stream. After cooling, the reaction mixture is poured into a large amount of methanol with constant stirring, producing a precipitate that is washed thoroughly with hot water and methanol, collected on a filter, and dried at 100° C. under vacuum for 24 hours to afford a pure polyamide-imide containing heterodiamondoid components in the polymer backbone.
[0285] A 4-(1-heterodiamondoidyl)-1,3-benzenediol (20.5 mmol) and 4,4′-difluorobenzophenone (4.468 g, 20.5 mmol) mixture is dissolved in 35 mL DMAc and 10 mL toluene in a reaction flask fitted with a nitrogen blanket, mechanical stirrer, and a Dean-Stark trap. To this mixture K 2 CO 3 (2.969 g, 21.48 mmol) is added while stirring and heating to reflux. Reflux is held at around 130° C. for about 1 hour followed by the gradual removal of toluene from the reaction flask until the flask temperature reaches around 160° C. (ca. 2 hours). The reaction mixture is maintained at 160° C. for 10 hours and then cooled to ambient temperature. The polymer solution is diluted with chloroform, filtered to remove the inorganic salts, acidified, and then precipitated into methanol. Filtration and drying of the product at about 120° C. under vacuum gives the homopolymer.
Example 59
Co-Polymerization from 4-(1-Heterodiamondoidyl)-1,3-Benzenediols and 2,2-Bis(4-Hydroxyphenyl)propane by Nucleophilic Aromatic Substitution
[0286] Co-polymerizations are carried out with different molar ratios of co-monomers (2,2-bis(4-hydroxyphenyl)propane and a 4-(1-heterodiamondoidyl)-1,3-benzenediol) using either DMAc or tetramethylene sulfone (sulfolane) as solvent. For instance, a 4-(1-hetero diamondoidyl)-1,3-benzenediol (10.25 mmol) and 2,2-bis(4-hydroxyphenyl)propane (10.25 mmol) and 4,4′-difluorobenzophenone (4.468 g, 20.5 mmol) can be dissolved in 35 mL DMAc and 10 mL toluene in a reaction flask fitted with a nitrogen blanket, mechanical stirrer, and a Dean-Stark trap. To this mixture K 2 CO 3 (2.969 g, 21.48 mmol) is added while stirring and heating to reflux. Reflux is held at around 130° C. for about 1 hour followed by the gradual removal of toluene from the reaction flask until the flask temperature reaches around 160° C. (ca. 2 hours). The reaction mixture is maintained at 160° C. for 10 hours and then cooled to ambient temperature. The polymer solution is diluted with chloroform, filtered to remove the inorganic salts, acidified, and then precipitated into methanol. Filtration and drying of the product at about 120° C. under vacuum gives the copolymer. If sulfolane is used as the solvent, the co-polymers are Soxhlet extracted with methanol to remove solvent and salts from the insoluble polymer.
Example 60
Poly(3-benzyloxypropyl malate-co-ethyl heterodiamondoidyl malate (85/15) from 3-Benzyloxypropylmalolactonate and Ethyl Heterodiamondoidyl Malolactonate by Anionic Ring-Opening Co-Polymerization
[0287] A flask is charged with a mixture of 3-benzyloxypropylmalolactonate (85 mol %), ethyl heterodiamondoidyl malolactonate (15 mol %) and tetraethylammonium benzoate (10 −3 eq. per mole of total moles of the co-monomers, acting as an initiator of the anionic ring-opening co-polymerization) under nitrogen. The mixture is then well stirred and warmed to 37° C. under nitrogen atmosphere and is maintained at this temperature for 15 days. After completion of the co-polymerization reaction, the co-polymers are collected and washed with small amount of water, ethanol, and dried in vacuum for about 24 hours.
Example 61
Phenyl Heterodiamondoid-Modified PEGs [Poly(ethylene glycol)s]from Alcoholate of Heterodiamondoidylphenol
[0288] To a stirred solution of a poly(ethylene gylcol) (PEG, 1 mmol) in 15 mL dichloromethane, 1 mL of triethylamine is added. This solution is cooled in an ice bath under nitrogen atmosphere. Then 1 g of 4-toluenesulfonylchloride (5.2 mmol) is added. The reaction is continued at 0° C. for 2 hours and then the mixture stirred at room temperature overnight. The product is precipitated in diethyl ether. An additional recrystallization from ethanol is performed in order to remove the triethylammonium chloride formed during the reaction affording a pure PEG tosylate.
[0289] Under a nitrogen atmosphere, a heterodiamondylphenol (4 mmol) dissolved in 70 mL of freshly distilled dichloromethane is added dropwise to 0.24 g of sodium hydride suspended in 30 mL of distilled dichloromethane. The solution is stirred for 2 hours at room temperature before adding dropwise the PEG tosylate (a little excess) dissolved in 50 mL of dichloromethane. The reaction mixture is kept at 40° C. for 24 hours. The obtained polymer is precipitated in ethyl ether, recrystallized from ethanol and stored at 4° C.
Example 62
Water Soluble Poly(ethylene glycol)s (PEGs) Containing Heterodiamondoids for Potential Drug Delivery Purposes
[0290] Host-guest interactions are very important processes in human biology. The water solubility of drugs is a key factor in determining their medical efficacy in living tissue. In order to enhance drug efficiency, poly(ethylene glycol)s (PEGs) can be modified by heterodiamondoid hydrocarbon compounds at their OH terminal ending(s). These hydrophobic groups may be selected based upon their potentially strong interactions with other groups in “cavities” formed in PEG polymer chains and thus can help deliver the drugs which have low solubility in water. Examples are shown in FIG. 28 .
Example 63
Carbon-Rich Polymers for Nanolithography
[0291] Rapid advances in the miniaturization of microelectronic devices require the development of new imageable polymeric materials for 193 nm microlithography (The National Technology Roadmap for Semiconductors, Semiconductor Industry Association ( SIA ), San Jose, Calif., 1997). The design challenge for 193 nm resist materials is the trade-off between plasma-etch resistance (which requires a high carbon/hydrogen ratio in the polymer structure) and optical properties for lithographic performance.
[0292] FIG. 29 shows the design of a carbon-rich cyclopolymer incorporating both imageable functionalities (tert-butyl esters) for chemical amplification, and high etch-resistance moieties (heterodiamondoids based on tetramantanes, pentamantanes, hexamantanes and the like). To adjust the physical properties of polymers, such as wettability and adhesion properties, a wide range of co-polymers can be prepared. This was shown to be feasible for adamantane-containing cyclopolymers and co-polymers by D. Pasini, E Low and J. M. J. Fréchet ( Advanced Materials, 12, 347-351 (2000)), and those materials showed excellent imaging properties. In addition, since the synthetic routes involve free radical polymerization techniques, metal contamination of the underlying semiconductor substrates is not an issue, as is the case for polymers based on norbornene ( Chemical of Materials, 10, 3319 (1998); 10, 3328 (1998)). Furthermore, adamantane-containing polymers show high glass transition temperatures (T g ) and high deposition temperature (T d ) and good film-forming properties. Polymers based on heterodiamondoids would be expected to have even better properties.
Example 64
Soluble Heterodiamondoid-Containing Polyesters Based on Heterodiamondoid Bisphenol
[0293] Polyarylates derived from bisphenol and iso/terephthalic acid are well accepted as highly thermally stable materials. However, polyarylates are generally difficult to process because of their limited solubility in organic solvents and their high melting temperatures or high T g 's by virtue of their rigid structures. It has been reported that incorporation of bulky pendant cardo groups, such as adamantyl groups, into polymer backbones, results in enhanced thermal properties of the polymers compared with polymers containing aromatic bisphenols. As an example of this type of polymer, FIG. 26 shows the design of such polyesters.
Example 65
Soluble Heterodiamondoid Containing Polyamides Based on Heterodiamondoid Diamines
[0294] Aromatic polyamides attract much interest because of their high-temperature resistance and mechanical strength. However, the applications of polyamides are limited by processing difficulties arising from their low solubility in organic solvents and their high glass transition or melting temperature. A number of successful approaches to increasing the solubility and processability of polyamides, without sacrificing their thermal stability, employ the introduction of flexible or non-symmetrical linkages into the polymer backbone or the incorporation of bulky substituents, such as pendant groups, into the polymer backbone. The inter-chain interaction of the polymers can be decreased by the introduction of bulky pendant groups, resulting in improved solubility of the polymers. Generally, the incorporation of pendant groups results in amorphous materials with increased solubility in common organic solvents.
[0295] FIG. 27 presents an example of this design which incorporates heterodiamondoid groups in the polyamide backbone.
Example 66
Soluble Heterodiamondoid-Containing Polyimides Based on Heterodiamondoid Diamines
[0296] The outstanding properties of aromatic polyimides, such as excellent thermo-oxidative stability and superior chemical resistance, led to the use of polyimides in many applications such as insulating materials for electronics, semipermeable membranes for gas separations, and high-temperature adhesives and coatings (J. M. Sonnett, T. P. Gannett, Polyimides: Fundamental and Applications , M. K. Ghosh and K. L. Mittal, Ed., Marcel Dekker, New York, 1996). However, in general, aromatic polyimides are insoluble and intractable and are, only processable under extreme conditions. To overcome these processing problems, heterodiamondoid groups can be placed in polyimide polymer backbone ( FIG. 28 ), and in polyaspartimides ( FIG. 29 ).
Example 67
Soluble Heterodiamondoid Containing Polyamide-Imides Based on Heterodiamondoid Diamide-Dicarboxylic Acids and Diamines
[0297] Aromatic polyimides are recognized as a class of high performance materials because of their remarkable thermal and oxidative stabilities and their excellent electrical and mechanical properties, even during long periods of operation. Unfortunately, strong interactions between polyimide chains and their rigid structure make them intractable. Poor thermoplastic fluidity and solubility are the major problems for wide applications of polyimides. On the other hand, polyamides have the advantage of good solubility and processability, as do polyetherimides. Therefore, polyamide-imide or polyetherimide might be the most useful materials, combining the advantages of both polyimides (such as high-temperature stability) and polyamides (such as good processability). In combination with the advantages of diamondoid hydrocarbons, we present a sample design of a polyamide-imide containing heterodiamondoid groups in the polymer chain ( FIG. 30 ). The diamines involved in the polymerization reaction could be either heterodiamondoid diamines such as shown in FIG. 29 or other aromatic diamines.
|
This invention is related to heteroatom containing diamondoids (i.e., “heterodiamondoids”) which are compounds having a diamondoid nucleus in which one or more of the diamondoid nucleus carbons has been substitutionally replaced with a noncarbon atom. These heteroatom substituents impart desirable properties to the diamondoid. In addition, the heterodiamondoids are functionalized affording compounds carrying one or more functional groups covalently pendant therefrom. This invention is further related to polymerizable functionalized heterodiamondoids. In a preferred aspect of this invention the diamondoid nuclei are triamantane and higher diamondoid nuclei. In another preferred aspect, the heteroatoms are selected to give rise to diamondoid materials which can serve as n- and p-type materials in electronic devices can serve as optically active materials.
| 2
|
CLAIM OF PRIORITY
[0001] This application is a US non-provisional, utility application that claims, without relinquishing future claims, no currently known priority to any previous US patent application or other equivalent documentation.
FIELD OF THE INVENTION
[0002] The invention relates to liners for storage compartments, and in particular motor vehicle cargo spaces, such as the rear compartment of a sport utility vehicle (SUV), for example.
BACKGROUND OF THE INVENTION
[0003] Owners of sport utility vehicles (SUV) frequently use them for hauling trash and yard trimmings to disposal stations. The cargo carrying compartments of most modern day SUV's are finished with fabric or composition materials. Unless the compartment is lined, these materials can become easily cut (e.g. by rose bush thorns or barbs) or scarred. A lining is also desirable for keeping the cargo compartment clean. Small leaves, bush berries, twigs, etc. become dislodged and fall into, and become difficult to remove from, crevices and below the seats.
[0004] Usually the owner attempts to use a piece of canvas, a plastic tarp, a blanket, or the like, as a liner for the storage compartment. A disadvantage of this arrangement is that the tarp or blanket must be propped up on the sides and also at both the front and rear of the compartment. Otherwise, there is no cover for the upright boundaries of the compartment which are usually made of less durable materials than the floor and need protection the most. Also, even if the liner is initially successfully propped, the props are easily knocked down by the trash or other cargo as it is inserted into the compartment.
DESCRIPTION OF THE RELATED ART
[0005] The relevant prior art involving cargo liners includes:
[0006] U.S. Pat. No. 3,653,710 issued to Barnard on Apr. 4, 1972 entitled “STORAGE COMPARTMENT LINER WITH INFLATABLE SUPPORT RIBS” that describes a liner of sheet fabric construction. It includes a bottom that is approximately the same size as the compartment floor. A side wall is provided on at least the sides and forward end. At least some of the walls include inflatable ribs for giving the side walls standup rigidity.
[0007] U.S. Pat. No. 4,516,906 issued to Krein on May 14, 1985 entitled “Free standing, waterproof lining for truck industry” that describes a method of installing a continuous moisture proof essentially disposable film liner within a conventional cargo trailer to protect moisture sensitive cargo during shipment. A polyolefin bag is inflated directly into an empty tractor trailer by attaching the lower edge of the bag opening along the bottom of the doorway of the trailer and blowing a gentle stream of air into the bag as sufficient tension is applied to the upper edge and surface of the bag to direct the air to the rear of the trailer. In this manner, the bag inflates from the rear of the trailer forward, thus pushing the air trapped between the bag and the inside of the trailer out the open doorway without the bag exiting the trailer. Once the bag is properly inflated and in contact with the inside of the trailer, it has been found that it tends to remain in place for sufficient time to load the cargo, even without continued use of the blower.
[0008] U.S. Pat. No. 5,683,132 issued to Danzo, et al. pm Nov. 4, 1997 entitled “Sport utility vehicle cargo area liner” that describes a sport utility vehicle cargo area liner is provided which is made of a flexible semi-rigid material such as ABS plastic. The liner has a bottom, two side walls each of which have at their uppermost edges near the wheel well a ledge which fits over the wheel well, and a leading edge and trailing edge. The leading and trailing edges are curved upwardly to allow the liner to easily slide over the sill of the sport utility vehicle cargo area and also to allow objects longer than the liner itself to be placed into the cargo area without the necessity of removing the liner or interfering with the vehicle seats. A stop strap system with a quick disconnect feature is provided to keep the liner safely in place yet it allows the quick removal of the liner. A harness is also provided to secure items in the liner.
[0009] U.S. Pat. No. 7,597,373 issued to McAuliffe, Jr. on Oct. 6, 2009 entitled “Flexible adjustable cargo area liner for station wagons, minivans and sport utility vehicles” that describes a flexible adjustable liner for station wagons, minivans and SUVs comprising a water-resistant material with sealed bottom, front and side sections to prevent spillage or leakage into the storage area, and a rear section that opens and closes with the tailgate or hatch door, thereby allowing cargo items to be easily placed onto or removed from the liner. The liner is suspended by an adjustable tether-support system. The adjustable support system comprises a system of cords that are attached along the ceiling or upper windows of the vehicle via a series of suction cups and/or the original equipment clothes hooks, conforming the liner to the entire storage area. The cords are adjustable in length and are set by spring-detent cinches to vary the coverage of the liner across the cargo area.
[0010] Various implements are known in the art, but fail to address all of the problems solved by the invention described herein. One embodiment of this invention is illustrated in the accompanying drawings and will be described in more detail herein below.
SUMMARY OF THE INVENTION
[0011] The present invention relates to a removable, drapable liner for a cargo space of a vehicle.
[0012] In a preferred embodiment, the removable, drapable liner may have a base and four sides that may all be made of a flexible, tear resistant, water resistant fabric. The removable, drapable liner is preferably transformable between a stored state, in which it may fold flat or be rolled up, and a drapable, open-topped, box-shaped state when it may be used to provide protection for a cargo space of a vehicle.
[0013] Although box shaped, the liner may not be rigid or self standing. In a preferred embodiment, the removable, drapable liner may have up to four supportive draping strips, each forming a part of, and extending along substantially the entire length of, a join between two sides of the liner. These supportive draping strips may provide sufficient support to easily conform the liner to the shape of the cargo space, effectively drapping it against the sides and base of the cargo container. In such a configuration the liner is both easy to fill and maximizes the use of the cargo space, while protecting the vehicle.
[0014] Therefore, the present invention succeeds in conferring the following, and others not mentioned, desirable and useful benefits and objectives.
[0015] It is an object of the present invention to provide a cargo space liner that is easy to use and easy to clean.
[0016] It is another object of the present invention to provide a liner for transporting recyclable materials that is itself made of recyclable material.
[0017] Yet another object of the present invention is to provide a cargo liner that may be printed on or painted for branding or advertising purposes.
[0018] Yet another object of the present invention is to provide a cargo liner having a simple, easy to fabricate design that minimizes both material and manufacturing costs.
[0019] Still another object of the present invention is to provide a cargo liner that may be easily and quickly removed from the cargo space.
[0020] Still another object of the present invention is to that, after removal, may be easily and quickly cleaned by turning upside down and shaking, sweeping or washing.
[0021] Yet another object of the present invention is to provide a cargo liner that is easily and quickly stored when not in use.
[0022] Still another object of the present invention is to provide a cargo liner that may be turned upside down and easily and quickly used to cover equipment, materials and or other articles, either indoors or outdoors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 shows an isometric view of a preferred embodiment of present invention.
[0024] FIG. 2 shows an isometric view of a preferred embodiment of the present invention in a flat, rolled or folded, stored state within a cargo space of a vehicle.
[0025] FIG. 3 shows an isometric view of a preferred embodiment of the present invention in a drapable, open-topped, box-shaped state and containing objects to be transported.
[0026] FIG. 4 shows a plan view of materials sized to form an embodiment of a removable, drapable liner.
[0027] FIG. 5 shows an isometric view of a supportive draping strip of a preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] The preferred embodiments of the present invention will now be described with reference to the drawings. Identical elements in the various figures are identified with the same reference numerals.
[0029] Reference will now be made in detail to embodiment of the present invention. Such embodiments are provided by way of explanation of the present invention, which is not intended to be limited thereto. In fact, those of ordinary skill in the art may appreciate upon reading the present specification and viewing the present drawings that various modifications and variations can be made thereto.
[0030] FIG. 1 shows an isometric view of a preferred embodiment of a removable, drapable liner 100 of the present invention.
[0031] In a preferred embodiment, the removable, drapable liner 100 may have a base 130 and four sides 140 . The base 130 and the four sides 140 may all be made of a suitable material that may be a flexible, tear resistant, water resistant fabric.
[0032] In FIG. 1 , the removable, drapable liner 100 is shown in a drapable, open-topped, box-shaped state 160 . This drapable, open-topped, box-shaped state 160 may be facilitated by, for instance, by one or more supportive draping strips 170 . Each of the supportive draping strips 170 may form a part of, and extend along substantially the entire length of, a join between two sides of the liner. The supportive draping strips 170 may be configured such that when the removable liner is in the drapable, open-topped, box-shaped state, the supportive draping strips 170 protrude outwards, and away from, the liner.
[0033] The supportive draping strips 170 may, however, allow the removable, drapable liner 100 to be quickly and easily transformed into a flat, rolled or folded, storable state 220 (not shown in FIG. 1 ).
[0034] The flexible, tear resistant, water resistant fabric that the removable, drapable liner 100 may be made of may, for instance, be a suitable woven or nonwoven fabric such as, but not limited to, a polyethylene, a polypropylene fabric, a suitably coated canvas, a tarpaulin fabric, a cotton fabric, a bamboo fabric or some combination thereof.
[0035] In a preferred embodiment, the removable, drapable liner 100 may be made from a flexible, tear resistant, water resistant fabric 150 that may be fully or partially recyclable.
[0036] FIG. 2 shows an isometric view of a preferred embodiment of the removable, drapable liner 100 in a flat, rolled or folded, stored state 220 within a cargo space 110 of a vehicle.
[0037] FIG. 3 shows an isometric view of a preferred embodiment of the removable, drapable liner 100 the present invention in a drapable, open-topped, box-shaped state 160 within a cargo space of a vehicle 210 . The removable, drapable liner 100 may contain objects to be transported 310 . A function of the removable, drapable liner 100 may, for instance, be to protect the cargo space of a vehicle 110 from damage or despoilment by the objects to be transported 310 .
[0038] The removable, drapable liner 100 shown in FIG. 3 is sized to be substantially equal in depth to the cargo space of a vehicle 210 . In alternate embodiments, the removable, drapable liner 100 may only be approximately equal in size to the cargo space of a vehicle 210 . Such an undersized or oversized removable, drapable liner 100 may rely on its drapability to conform to the dimensions of the cargo space of a vehicle 210 , especially as materials are added to the removable, drapable liner 100 .
[0039] The removable, drapable liner 100 may, for instance, be sized, when in said drapable, open-topped box-shaped state, to extend outward from a rear end of the cargo space 230 . The removable, drapable liner 100 may, for instance, be sized to extend outward from the rear end of the cargo space 230 by a distance in a range of 1 foot to 6 feet, though more preferably in a range of 1.5 feet to 2.5 feet.
[0040] When the removable, drapable liner 100 extends outwards from the rear end of the cargo space 230 , the removable, drapable liner 100 may form a substantially 3 sided liner within the cargo space of the vehicle 210 . The fourth side 140 may drape down toward the ground, allowing easy assess for placing objects such as, but not limited to, the objects to be transported 310 , into the removable, drapable liner 100 . Once the removable, drapable liner 100 is loaded, the fourth side 140 may then be draped over the top of the loaded objects, forming both a fourth side and a top, or partial top, to the load.
[0041] To unload the objects to be transported 310 , the procedure may be reversed. After opening the rear door of the vehicle 240 , the side 140 of the removable, drapable liner 100 forming the rear side and top may be unfolded and allowed to drape down toward, and if necessary, onto the ground. The removable, drapable liner 100 may then effectively be a three sided container, supported against the walls of the cargo space of the vehicle 210 . Such an arrangement may allow easy access for unloading the objects on the removable, drapable liner 100 .
[0042] FIG. 4 shows a plan view of materials sized to form an embodiment of a removable, drapable liner 100 .
[0043] The removable, drapable liner 100 may, for instance, be made from three pieces of fabric, a main piece of fabric 410 , a left side piece of fabric 420 and a right side piece of fabric 430 . The main piece of fabric 410 may be used to form the base 130 and the front and back sides 140 . The left side piece of fabric 420 and the right side piece of fabric 430 may be substantially equal in size and may, for instance, be used to form the left and right sides 140 of the removable, drapable liner 100 .
[0044] In a preferred embodiment, the main piece of fabric 410 may have a length that is substantially equal to the length of the left side piece of fabric 420 or the right side piece of fabric 430 plus twice the width of the left side piece of fabric 420 or the right side piece of fabric 430 . That is, the main piece of fabric 410 may have a length substantially equal to the base of the removable, drapable liner 100 plus the height of two sides of the removable, drapable liner 100 .
[0045] The removable, drapable liner 100 may then be formed by, for instance, joining the left side piece of fabric 420 to the main piece of fabric 410 along a first join line 440 , and the right side piece of fabric 430 to the main piece of fabric 410 along a second join line 440 . This joining may be accomplished by any suitable means such as, but not limited to, stitching, stapling, gluing, welding, sewing or some combination thereof.
[0046] A front portion of the main piece of fabric 410 may then be folded up along a first fold line 450 while the left side piece of fabric 420 and the right side piece of fabric 430 are folded up along their respective join lines 440 . A narrow edge of the left side piece of fabric 420 may then be joined to the main piece of fabric 410 to form a first side edge, while a narrow edge of the right side piece of fabric 430 may be joined to the main piece of fabric 410 to form a second side edge. Although this joining may be accomplished by any suitable means such as, but not limited to, stitching, stapling, gluing, welding, sewing or some combination thereof, in a preferred embodiment, the joining may be done by double stitching in accordance with the method described below so that the side edges may form supportive draping strips 170 .
[0047] This procedure may be repeated using a rear portion of the main piece of fabric 410 folded up along a second fold line 450 . In this way the rear side 140 of the removable, drapable liner 100 may be formed, along with two further supportive draping strips 170 .
[0048] Advantages of this method of construction include, but are not limited to, the ability to make the width of the base 130 of the removable, drapable liner 100 equal to the widest available rolls of the fabric being used. This may not only reduce material costs, but may also reduce material waste. Such a design may, for instance, also reduce labor costs by reducing the amount of stitching required to construct a removable, drapable liner 100 .
[0049] FIG. 5 shows an isometric view of a supportive draping strip 170 of a preferred embodiment of the present invention.
[0050] The supportive draping strips 170 may be formed by joining two sides 140 of the removable, drapable liner 100 using a suitable join method such as, but not limited to, a double stitched seam 460 . The join is preferably made so that the supportive draping strips 170 protrudes outward from the removable, drapable liner 100 , i.e. outward from the space enclosed by the joined base 130 and the sides 140 . Having the supportive draping strips 170 protrude out may have a number of advantages such as, but not limited to, simplifying the manufacture of the removable, drapable liner 100 , making the removable, drapable liner 100 easier to use, and allowing maximum use of the inside space of the removable, drapable liner 100 .
[0051] The supportive draping strips 170 may typically have a width in a range of 0.25 to 3 inches, though they are more preferably in a range of 0.5 to 2 inches, and most preferably in a range of 0.75 to 1.5 inches.
[0052] The Society for Plastics Industry, based in Washington, D.C., has classified plastics according to the following code:
Type 1—PETE Polyethylene Terephthalate (PET)
Soda & water containers, some waterproof packaging.
Type 2—HDPE High-Density Polyethylene
Milk, detergent & oil bottles. Toys and plastic bags.
Type 3—V Vinyl/Polyvinyl Chloride (PVC)
Food wrap, vegetable oil bottles, blister packages.
Type 4—LDPE Low-Density Polyethylene
Many plastic bags. Shrink wrap, garment bags.
Type 5—PP Polypropylene
Refrigerated containers, some bags, most bottle tops, some carpets, some food wrap.
Type 6—PS Polystyrene
Throwaway utensils, meat packing, protective packing.
Type 7—OTHER Usually layered or mixed plastic.
No recycling potential—must be landfilled.
[0067] Of these, types 1 and 2 are commonly recycled, while type 4 is less commonly recycled. The other types are generally not recycled, except perhaps in small test programs. Common plastics polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) do not have recycling numbers.
[0068] Although plastic recycling is in its infancy, and the process may be messy and inefficient, advances are, and will continue to be made. Making the removable, drapable liner 100 of recyclable materials, including recyclable plastics may therefore be highly desirable. In a alternate preferred embodiment, the removable, drapable liner 100 may be made from fabrics that are recyclable materials such as, but not limited to, woven or nonwoven fabrics having plastics fibers that are classified as type 1, 2 or 4 type plastics by the SPI.
[0069] Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made only by way of illustration and that numerous changes in the details of construction and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention.
|
A removable, drapable liner intended for protecting a cargo space of a vehicle. The liner has a base and four sides, all being made of a flexible, tear resistant, water resistant fabric, and is transformable between a stored state, in which it may fold flat or be rolled up, and a drapable, open-topped, box-shaped state. The liner is neither rigid nor self standing, but does have supportive draping strips that provide sufficient support to easily conform the liner to the shape of the cargo space, effectively draping it against the sides and base of the cargo container. The four supportive draping strips each form part of a join between two sides of the liner. The draping strips extending along the length of the joins. Draped against the cargo space, the liner is easy to fill and maximizes the use of the cargo space, while protecting the vehicle.
| 1
|
CROSS-REFERENCE TO RELATED DOCUMENTS
This U.S. Utility Patent Application claims priority to U.S. Provisional Patent Application 61/075,158, filed Jun. 24, 2008, and U.S. Provisional Patent Application 61/100,488, filed Sep. 26, 2008. This reference and all additional references cited in this specification, and their references, are incorporated by reference herein where appropriate for teachings of additional or alternative details, features, and/or technical background.
BACKGROUND
The term Guided Motion Knees was formulated in the mid-1990's in an effort to conceptualize features in the femoral and tibial components of a total knee replacement (TKR) which would guide the motion of the knee during flexion and extension. The particular motion characteristics of interest were those on a natural anatomic knee itself; as the knee is flexed, posterior displacement (or rollback) of the femur on the tibia, external rotation of the femur on the tibia, and rotational and anterior-posterior laxity at all angles of flexion. Guided Motion in a basic form has already been addressed in many previous designs dating back to the early 1970's, using the geometry of the lateral and medial bearing surfaces, as well as central cam-post mechanisms. (Raymond P. Robinson, The Early Innovators of Today's Resurfacing Condylar Knees , Journal of Arthroplasty, Vol. 20, Suppl 1, 2005). Almost all of the total knee replacements on the market today have similar shapes for the lateral and medial sides, such that there is little lateral or medial bias to the motion. However, in recent years, designs have emerged which have attempted to produce asymmetric motion. One of the first was the Medial Pivot Knee (based on early concepts by Freeman et al., Wright Manufacturing) and the Journey Knee (Smith & Nephew). The Medial Pivot Knee is based on a completely stable medial side and a rotatable lateral side. The Journey Knee has more conformity medially than laterally with a slightly convex lateral tibial surface, together with a cam-post mechanism to produce femoral rollback with flexion. There is evidence that these designs do bring knee kinematics and function closer to natural anatomic than symmetric designs. However, there continues to be a need for a total knee replacement which, more perfectly, reproduces normal kinematics and function, and feels like a natural knee.
BRIEF SUMMARY
In one embodiment of the present invention there is provided a prosthetic knee joint comprising: a tibial component comprising an asymmetric lateral dished surface and an anteriorly elevated medial dished surface, and a protrusion located between the lateral dished surface and the anteriorly elevated medial dished surface, anterior portion of the protrusion defining an anterior ramp and posterior portion of the protrusion defining a posterior ramp, the medial dished surface further comprising an external rotation axis; a femoral component comprising asymmetric lateral and medial condylar shaped surfaces, an anterior femoral groove, and a cupola located between the lateral and medial condylar surfaces, the cupola being a continuation of the femoral groove; the lateral condylar shaped surface is in sliding contact with the lateral dished surface, the medial condylar shaped surface is in sliding contact with the medial dished surface, and, for angles of flexion within a specified range, a surface of the cupola is in contact, and conformal with the posterior ramp; the lateral and the medial condylar surfaces and the posterior ramp and the surface of cupola are respectively configured to maintain contact as the lateral condylar surface displaces posteriorly, with respect to the external rotation axis, in concert with flexure.
In embodiments is additionally disclosed a prosthetic knee joint wherein the medial condylar surface and the medial dished surface, at zero degree flexure, is substantially conformal. Embodiments also comprise the lateral condylar surface and the lateral dished surface, at zero degree flexure, is substantially conformal anteriorly and non-conformal posteriorly; that the medial and the lateral condylar surfaces have arcuate sagittal profiles comprising a connected sequence of substantially circular arcs; and that the medial condylar surfaces have arcuate sagittal profiles comprising a connected sequence of substantially circular arcs, having a diminished radius relative to the arc immediately anterior; and that the cupola surfaces and the ramp surfaces are mathematically continuous and have substantially non-constant derivatives; and that the cupola surface transitions to the adjoining surface with a rounded edge having a radius of greater than 3 millimeters. Additional embodiments include that the specified range of angles of flexion extends from 30 or 60 degrees to maximum flexion. Maximum flexion is typically approximately 155 degrees.
Embodiments further include that the medial dished surface, the lateral dished surface, and the ramp are defined as surfaces conformal to an envelope of maxima of the distal femoral surfaces resulting from a succession of incremental placements of the femoral component along the desired motion track corresponding to joint flexure; and that the tibial component further comprises a ligament clearance depression in the posterior vertical wall and the femoral component further comprises a ligament clearance notch located between the condylar surfaces; and that the tibial component and femoral component comprise separable portions contained by the ligament clearance depression and the ligament clearance notch respectively.
Embodiments also include an artificial knee comprising: a first component having an outer generally J-shaped surface and an inner generally J-shaped surface: the outer generally J-shaped surface comprising a first asymmetric bilateral lobular profile comprising a first lobe and a second lobe, the first lobe having first radius, and the second lobe having a larger second radius, the first asymmetric bilateral lobular profile being adjacent to a second accurate asymmetric bilateral profile, the bilateral profiles defined by an intermediate off-center depression of non-uniform depth traversing along the generally J-shaped outer surface, the depression including, along its traverse, a pit; the inner generally J-shaped surface comprising a first lateral surface, a bottom surface and a second lateral surface, the second lateral surface being taller in height than the first lateral surface, and the bottom surface comprising a ridge extending between the first lateral surface and the second lateral surface; a second component having an upper surface, a bottom surface and a circumscribing transverse surface between the upper surface and the bottom surface: the upper surface defining a first and second dished section, asymmetric to one another, the first dished section being anteriorly elevated with respect to the second dished section and the second dished section having a shallower profile than the first dished section, and the upper surface further defining an intervening elevated section between the two dished sections, the intervening elevated section having a discrete mound component emanating therefrom, the mount having a first slope and a second opposing slope, the first slope being angled steeper than the second opposing slope; the bottom surface defining one or more protrusions from such surface, wherein the mound of the intervening elevated section of the second component is configured to fit within the pit of the first component, the first lobe of the first component is configured to fit within the first dished section of the second component and rest on a surface thereof when the mound is fit within the pit, and the second lobe of the first component is configured to fit within the second dished section of the second component and rest on a surface the reof when the mound is fit within the pit.
Definitions
Condylar shaped surface is a surface located on the distal portion of the femoral component and having the shape of an anatomic condyle.
Conformity between two curves means that the radii at the contact are nominally the same.
Cupola is a cavity or depression in the distal surface of the femur located between the medial and lateral condyles. The posterior of the cupola serves as a surface which contacts the ramp or post, protruding from the tibia, during flexion.
Cupola height is the distance between the base of the cupola and the profile of the lateral and medial femoral condyles as seen in the sagittal view.
Drape is a free-form surface which overlays a composite of surfaces without penetrating any of the surfaces.
External rotation of the femur is the rotation of the femur about an axis, located on the medial condylar surface of the tibia, which is parallel to the long axis of the tibia.
External rotation axis is the axis on the medial side of the tibia about which the external femoral rotation takes place.
Frontal plane is mutually perpendicular to the sagittal and transverse planes.
Laxity is the amount of displacement or rotation that can occur due to lack of conformity between two adjacent surfaces.
Post is a ramp with a posterior surface having a slope of greater than approximately 45 degrees.
Protrusion is a mound-like structure, projecting upward from the tibial component. The surface of the protrusion defines an anterior ramp having an average slope rising from the anterior of the protrusion toward the posterior, and a posterior ramp having an average slope rising from the posterior of the protrusion toward the anterior.
Ram is the surface of a protrusion from the proximal surface located between the medial and lateral tibial bearing surfaces. The posterior of the ramp serves as a contact surface which contacts the cupola contained portion of the femur.
Sagittal plane is a plane which divides the femur and tibia into left and right halves
Transverse plane is a horizontal plane perpendicular to the long axis of the tibia.
Transverse plane projection is the geometric projection of a specified line segment onto the transverse plane.
BRIEF DESCRIPTION OF FIGURES
The following detailed description, given by way of example, will be best understood in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view of the femoral component.
FIG. 2 is an overhead view of the femoral component on the transverse plane, with anterior above, posterior below, lateral left, and medial right.
FIG. 3 is a frontal view of the femoral component on the frontal plane, with superior above and inferior below.
FIG. 4 is a side view of the femoral component on the sagittal plane, with anterior to the right, posterior to the left.
FIG. 5 shows sections S 1 thru S 9 from the sagittal view, showing the profiles of the femoral bearing surfaces.
FIG. 6 shows sagittal sections FL, FC, and FM, from the frontal view, showing the lateral profile, the cupola profile and the medial profile.
FIG. 7 shows the construction of a typical medial profile of the femoral component using circular arcs.
FIG. 8 shows the construction of a typical lateral profile of the femoral component using circular arcs.
FIG. 9 shows the medial profile located on a section of the tibial bearing surface at zero degrees flexion.
FIG. 10 shows the medial profile located on a section of the tibial bearing surface at 30 degrees flexion.
FIG. 11 is a perspective view of the tibial component.
FIG. 12 is a view of the tibial component on the transverse plane.
FIG. 13 is a view of the tibial component on the frontal plane.
FIG. 14 is a view of the tibial component on the sagittal plane.
FIG. 15 shows sections F 1 thru F 5 from the sagittal view, showing the profiles of the tibial bearing surfaces.
FIG. 16 shows sagittal sections TL, TC, and TM, from the frontal view, showing the lateral profile, the ramp profile and the medial profile.
FIGS. 17 , 18 , 19 show the sagittal sections through the lateral condyle, the ramp-post, and the medial condyles, at zero degrees flexion.
FIGS. 20 , 21 , 22 show the sagittal sections through the lateral condyle, the ramp-post, and the medial condyles, at 60 degrees flexion.
FIGS. 23 , 24 , 25 the sagittal sections through the lateral condyle, the ramp-post, and the medial condyles, at 120 degrees flexion.
FIG. 26 shows a section in the transverse plane through the contact area of the cupola and ramp at 60 degrees flexion.
FIG. 27 shows a section in the transverse plane through the contact area of the cupola and ramp at 90 degrees flexion.
FIG. 28 shows a section in the transverse plane through the contact area of the cupola and ramp at 120 degrees flexion.
FIG. 29 is a composite of femoral components at multiple positions in the prescribed motion path throughout the full range of flexion.
FIG. 30 is a sagittal plane view of the medial sections, corrected so that the lowest points lie on an arc RM.
FIG. 31 is a sagittal plane view of the lateral sections, corrected so that the lowest points lie on an arc RL.
FIG. 32 is a drape of the lower surface of the composite of corrected femoral components, which defines the tibial surface.
FIG. 33 is a tibial component where the surface including the bearing surfaces and ramp, is the aforementioned drape surface.
FIG. 34 shows two femoral components, the left being intended for resection of the cruciate ligaments, and the right being intended for retention of the posterior cruciate, together with a tibial component below which can be used with either femoral component.
DETAILED DESCRIPTION
During everyday activities, the knee joint experiences a variety of forces, including axial compressive and anterior-posterior shear, and moments, including varus-valgus and axial torque. The knee can achieve flexion angles of up to approximately 155 degrees, while the relative motions between the femur and the tibia include numerous combinations of femoral-tibial positional relationships at the bearing surfaces. Stability is essential, which is provided by a combination of bearing surface interaction, muscle forces and the soft tissues in and around the joint. There is now considerable evidence that the major anterior-posterior stability, of the femur with respect to the tibia, is derived from the medial side, which allows only a few millimeters of anterior-posterior displacement. In the anatomic knee, this stability is provided by the cruciate ligaments, together with the medial collateral ligament. The higher the compressive load, the more the stability is provided by the medial meniscus in combination with the dishing and anterior upsweep of the tibial plateau. In contrast, the lateral side of the knee is extremely mobile. During the full range of flexion, the lateral femoral condyle displaces posteriorly by about 20 mm. while the medial femoral displaces posteriorly only a few millimeters, and that only at the higher flexion angles. Hence the concept of knee mechanics is that the stability is provided by the medial side while the mobility is provided by the lateral side. This mode of function is necessary for the patient to feel that their artificial knee feels like their natural anatomic knee.
The Ramp Knee, a type of Guided Motion Knee, reproduces these mechanical properties, due to the design of the femoral and tibial bearing surfaces and the interaction of a central ramp or post on the tibial component which locates within a housing or cupola in the center of the femoral component. The cupola is blended to the surrounding bearing surfaces laterally, medially, anteriorly and posteriorly. The sagittal profiles in the centers of the lateral and medial condyles preferably resemble natural anatomic shapes. The radius of curvature of the distal sagittal profile of the medial side condyle is constant up to about 30 degrees flexion while the lateral condylar surface has a radius of curvature, at the point of tibial contact, which reduces with flexion. The depth of the femoral cupola reduces steadily from the distal end of the femur, where it can preferably be 10-15 mm in depth, to the posterior, where it becomes less than 7 mm in depth.
The respective medial and lateral tibial surfaces may be generated by mathematically superimposing multiple femoral surfaces, each of which corresponds to the correct orientation of the femur, with respect to the tibia, for a full range of flexion angles. The correct orientation of the femur may be determined to be a predefined function of the external femoral rotation and posterior displacement of the femur as a function of flexion angle based on empirical data of the neutral path of motion. The neutral path of motion is the trajectory followed by the femur, without the influence of superimposed shear or torque forces. Therefore, characterization of the orientation includes, in part, axial rotation of the femur about an external rotational axis in the tibia, together with corresponding posterior displacements of the femur on the tibia. The external rotation axis can change in position with flexion, but is within approximately 10 mm of the medial femoral-tibial contact point. The point of contact of the medial condyle and the associated external rotational axis undergoes a small displacement over the full range of flexion. A resulting surface of femoral contact is created by incrementing the flexion angle of the femur in small increments (i.e. 5 to 15 degrees) and generating a drape or envelope of the lower surfaces of the composite femoral positions.
Typically the medial side of the femur displaces 2-4 mm while the axial rotation is about 15-20 degrees, resulting in a lateral side posterior displacement of about 15-20 mm. In order to accommodate such a large lateral displacement, the transverse axis of the femur at zero degrees flexion, is rotated internally on the tibia, so that the lateral contact location is anterior to the center of the tibial plateau, resembling the screw-home mechanism of the femur on the tibia, as the femur comes into terminal extension. The lower surface of the composite envelope of the femoral surfaces, will be conformal with the tibial surface and is consistent with the required neutral path of motion. However it will be understood that for purposes of tolerances and to allow some laxity to occur, the tibial surface will be relieved slightly to avoid a tight femoral-tibial fit. In any case, laxity is inherent in this tibial surface except at the extremes of the flexion range. To produce this behavior, extra femoral surfaces can be added to provide the required laxity to the composite at the extremes.
After generating the composite femoral positions, a modification in the sagittal plane is carried out whereby the profiles are placed on arcs. On the medial side, the arc is of small radius, for example 40-50 mm, while on the lateral side, the arc is of large radius, for example 70-100 mm. The anterior parts of the arcs will preferably be of smaller radius than the posterior, to allow for a high flexion range and posterior displacement of the lateral femoral condyle in flexion. The final step is to mathematically smooth the composite of the corrected femoral surfaces, using a drape function. This resulting smoothed surface defines that portion of the tibia which is contacted by the condyles. The tibial surface also includes the central ramp or post surface which is similarly generated by the envelope of successive positions of the femoral cupola. This process results in a central ramp or post which is not as steep as a typical central post on typical PS total knees. However it will be appreciated that the steepness of the ramp will be determined by the pattern of cupola heights from the distal end of the femur to the posterior. An important feature of both the femoral and tibial surfaces is that all of the curves are continuous without corners or edges, for the purpose of avoiding stress concentrations and providing large areas of contact.
FIG. 1 is a perspective view of the femoral component 10 , where the general peripheral shape matches an average anatomical knee shape, Two short posts 20 , 25 are typically used for fixation. The upper surface of a shallow cupola 30 is seen centrally. FIG. 2 shows at the superior the typical anatomic shape of the patella groove 40 or trochlea. At the inferior, the lateral femoral condyle 50 is more prominent than the medial 60 . FIG. 3 shows the frontal view, where the anterior view of the lateral and medial femoral condyles are shown. The radii are 23 mm, which blends well with the patella groove 40 , and is typical of an anatomic shape. For a femoral component this radius can be increased, particularly towards the outsides of the component. FIGS. 2 and 3 show the planes of sagittal sections through the lateral femoral condyles (FL) 70 , center of the cupola (FC) 90 , and the medial femoral condyles (FM) 80 . FIG. 4 shows the sagittal view, with anterior to the right. The two fixation posts 20 , 25 can be seen. This view also shows the sections of the profiles of the condylar bearing surfaces 100 , which are shown in FIG. 5 .
FIG. 5 shows the condylar profiles around the femoral component, S 1 -S 6 being the profiles which contact the tibial bearing surfaces, S 7 -S 9 being on the patella trochlea. The height of the cupola H 110 is maximum in the region of profile 6 , and then the height reduces around the bearing surface until it reaches a minimum at about profile S 2 . This can be seen more clearly in FIG. 6 . The depth P 130 of section S 1 can be zero resulting in a cylindrical section of bearing surface running from lateral to medial. The difference between the maximum D 120 and minimum P 130 represents the height of the ramp or post on the center of the tibial component. The rate of change of heights also control the slope of the ramp or post. The angle of the posterior surface of the ramp to the horizontal will usefully be in the range of 30-90 degrees. The height at section S 1 will be less than or equal to the depth of the patella groove A 45 which is typically 7mm. However this may not have sufficient medial-lateral stability and hence a minimum depth of approximately 3 mm is preferable. As shown in FIGS. 6 , 7 , and 8 , the shapes of the lateral and medial profiles are different.
FIG. 7 shows a preferred profile of the medial bearing surface. Arc FE 140 , center S 150 , is the upper trochlea. From E to C 160 , center R 170 , is a constant radius, or close to constant. The arc CB 180 , center Q 190 , is reduced; and the arc BA 200 , center P 210 , is further reduced to facilitate a high range of flexion. FIG. 8 shows the equivalent profile of the lateral bearing surface. In this case, arc D′C′ 220 , center Q′ 230 , is much larger than arc C′B′ 240 , center P′ 250 . These profiles resemble anatomic, and many ways of describing these profiles by arcs or spirals can be accomplished while retaining the general shapes. For the medial profile, the advantage is described by FIGS. 9 and 10 . At zero flexion, the femoral and tibial surfaces are close to conformity (arrow), such that anterior sliding of the femur on the tibia is restricted. When the knee flexes to 30 degrees, the sliding is still restricted 260 . From 30-60 degrees, there is less restriction. However the ramp-cupola will start to act between 30-60 degrees, preventing the femur from displacing anteriorly on the tibia.
FIG. 11 shows a perspective view of the tibial component 270 , with the posterior to the lower left. In the center of the face is a curved notch 280 , both to fit the anatomic contour of the upper tibia, and for passage of the posterior cruciate if this is retained. The notch 280 can also be seen at the bottom of FIG. 12 . FIG. 13 shows a posterior view where dished surfaces 290 , 300 that receive the corresponding condyles 50 , 60 are separated by a central protrusion. The anterior medial side 320 to the right of FIG. 13 is higher than lateral side 310 to the left. This again illustrates the differences between the more conforming medial side 300 and less conforming lateral side 290 . The dished medial tibial surface 300 will restrict anterior femoral sliding. The sections TL 340 , TC 350 , and TM 360 , are the locations of sagittal sections on the lateral side 370 , ramp 380 , and medial side 390 , shown in FIG. 15 . In FIG. 14 , the slope of the posterior ramp 400 and the slope of the anterior ramp 405 is seen. In this case the slope of the posterior ramp is 45 degrees, but various slopes are possible. A shallower slope will provide less definitive motion guidance, while a steeper slope will generally require a higher cupola, a disadvantage in regard to removal of bone when fitting to the femur. F 1 -F 5 are the locations of frontal plane sections, shown in FIG. 16 .
In FIG. 15 , the frontal radii of the lateral and medial bearing surfaces are shown. Except for the extreme anterior section F 5 , the frontal radii are constant from anterior to posterior, shown with the dashed arcs 410 . However, towards the posterior, F 1 , the arc radius is the same but the arc length is reduced because of the reduced central height. The advantage of the constant radius is that there can be close conformity of the tibial bearing surface with the femoral bearing surface throughout the entire flexion range, minimizing contact stresses. In this figure, it can be seen that the posterior ramp 400 is disposed approximately 2 mm to the lateral side, to match the cupola 110 seen in FIG. 5 , this feature of a lateral shift being anatomic.
FIG. 16 shows a comparison between the sagittal profiles of the lateral TL 370 and medial TM 390 bearing surfaces. The medial is more dished both anteriorly and posteriorly to provide anterior-posterior stability, although the femoral radius is larger in order to allow 2-4 mm of anterior-posterior laxity, especially in high flexion. The lateral profile is shallow anteriorly to allow internal femoral rotation in extension, the so-called screw-home mechanism, and posteriorly to allow posterior displacement of the lateral femoral condyle in flexion.
FIGS. 17-20 , respectively show the lateral, central and medial sections at zero degrees flexion. The low lateral conformity and high medial conformity have already been described. The anterior ramp 405 now acts to limit extension, although rocking is possible to allow up to 5 degrees of hyperextension. FIGS. 20-22 show the sections at 60 degrees flexion. Here, the posterior ramp 400 and cupola 110 is seen to be in contact. The ideal initial contact is in the range of 30-60 degrees flexion. Finally, FIGS. 23-25 show the sections at 120 degrees flexion. The lateral femoral condyle 50 is posterior on the tibial surface 330 , while the medial femoral condyle 60 has displaced 2-4 mm, these actions due to the posterior ramp 400 and cupola 10 and the relative dishing of the lateral 290 and medial 300 sides. Due to the differential displacements, the femoral component has rotated approximately 20 degrees externally about an axis 420 on the medial side of the medial tibial bearing surface. During rotation, the location of axis 420 may minimally displace within the medial tibial bearing surface. Such minimal displacement may, for example, be limited to less than approximately 5 millimeters.
FIG. 26 shows a section in the transverse plane of the cupola 110 and the posterior ramp R 400 , at 60 degrees flexion. The interior of the cupola is rounded, and so is the posterior surface of the ramp, such that there is close conformity, which maximizes the contact area and minimizes the contact stresses. The same situation occurs at 90 degrees flexion ( FIG. 27 ) and 120 degrees flexion ( FIG. 28 ). This conformal contact is a major advantage in protecting the ramp, or post, from edge damage.
FIGS. 29-33 show one method for generating surface of the tibial component 270 . A composite is made of the femoral components at increments of flexion ( FIG. 29 ). The motion path is described by simple empirical equations which describe the axial rotation and the posterior displacement of the femoral component 10 on the tibial component 270 . In our case we use 20 degrees of external rotation and 4 mm of posterior displacement. However there are many values which will produce similar tibial component shapes and which would function satisfactorily. FIGS. 30 and 31 show that the sagittal sections are aligned on arcs RM 440 medially and RL 450 laterally. The radii of the arcs have been determined in previous studies of knee replacements to provide the correct combinations of stability and laxity. A drape function over the lower part of the composite of femoral components produces a surface which will replicate the combined motions of the femur, as shown in FIG. 32 . It will be appreciated that the tibial surface is modified to avoid an exact fit with the femoral component. This can be done by building in small side-to-side laxity movements in the femoral composites. The final tibial component 270 is thus generated ( FIG. 33 ) and completed by making a posterior notch 280 , and relieving the posterior of the medial side with a 45 degree chamfer to avoid impingement with the posterior femoral cortex in high flexion.
FIG. 34 shows a convenient combination of components which can be made. The standard femoral component 10 and tibial component 270 as described thus far are shown on the left. However there are many surgical cases where it is preferred to retain the posterior cruciate ligament. To accommodate this, a slot or ligament clearance notch 460 is made in the femoral component 470 . The posterior notch or ligament clearance depression 280 on the tibial component 270 allows passage of the posterior cruciate as stated already. The ramp does not interfere with motion of the cruciate retaining femoral component. However there is now no cupola to interact with the ramp and provide the posterior displacement. This function is now carried out by the posterior cruciate ligament. In an embodiment, the ligament clearance depression and ligament clearance notch may be formed by removal of separable portions of the respective tibial and femoral components.
Statement Regarding Preferred Embodiments
While the invention has been described with respect to preferred embodiments, those skilled in the art will readily appreciate that various changes and/or modifications can be made to the invention without departing from the spirit or scope of the invention, in particular the embodiments of the invention defined by the appended claims. All documents cited herein are incorporated in their entirety herein.
|
A recess-ramp knee joint prosthesis comprising a femoral and a tibial component is configured to reproduce normal kinematics and function. Asymmetric condular surfaces and a cupola of the femoral component interact with corresponding dished surfaces and a ramp of the tibia thereby duplicating the behavior of the anatomical knee.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Stage of International Application No. PCT/AT2005/000444, filed Nov. 8, 2005, and which claims the benefit of Austrian Utility Model Application No. GM 805/2004, filed Nov. 8, 2004. The disclosures of the above applications are incorporated herein by reference.
FIELD
The invention relates to a method for controlling a hydraulic actuator of a friction clutch which comprises a pump driven by an electric motor controlled by a control system, a pressure line including a check valve and running to an actuator cylinder having an actuator piston, with the pressure in the actuator cylinder having to be controlled or feedback controlled, and a fast drain valve including a slider responsive to the pressure prevailing at the side of the pump facing it. In this connection, in particular the actuator of a multiple-disk clutch in the drivetrain of a motor vehicle is being thought of, on which particular demands are made due to the special characteristics of such clutches and to the special demands in motor vehicles with driving dynamic systems.
BACKGROUND
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
The special demands on the controllability of friction clutches are present both with respect to the precision of the setting of a specific torque and with respect to the speed of the control. The latter in particular on the release of the clutch, for instance on an ABS intervention or an ESP intervention. Furthermore, the electric motor should use as little energy as possible over all, that is it should also only run when necessary. There is also the demand for intrinsic safety. This means that the most secure state (usually that is the released clutch) should be adopted automatically in the event of system failure.
These demands also require an embodiment of the actuator in accordance with the preamble of the first claim, such as is, for example, the subject matter of WO 2004/040158 A2 of the applicant. Further details can be seen from this. An actuator of this type is cost-effective because the control valves required with conventional actuators can be dispensed with. The control of the electric motor for the actuation of the actuator is, however, demanding from a technical control viewpoint and is the subject of the present invention, which can be used independently of the specific construction and of the control of the electric motor itself.
SUMMARY
The object underlying the invention is thus to teach a method and a control system that permits the precise setting of a specific pressure, the very fast lowering of the pressure and the maintaining of the pressure using a minimum of electrical energy and is moreover intrinsically safe. The latter means that the pressure reliably falls on a failure of the control.
This is achieved in accordance with the invention in that a control variable for the electric motor is determined from the desired pressure and the actual pressure in the actuator cylinder, with at least two different control algorithms being carried out in dependence on the sign of the difference of the desired pressure and actual pressure. The control variable for the electric motor depends on its specific construction and control. It can be a permanently excited direct current motor with control of the current strength or voltage or any other controllable electric motor. The sign of the difference is to be understood as the sign preceding it. It is positive when the desired pressure is larger than the actual pressure and negative in the reverse case. It is zero when the pressure difference is smaller than a predetermined tolerance, with this also being able to be preset by a higher level system (for example a driving dynamics controller). The different control algorithms first permit a precise setting of a specific pressure with a positive sign and an extremely fast lowering of the pressure with a negative sign, and also additional measures to maintain the respective pressure in as energy saving a manner as possible. This takes the fact into account that the control path in the two operating states has a different structure and behaves differently due to the interaction of the check valve and the fast drain valve.
To build up the pressure with a positive sign, the control algorithm compares the desired pressure in the actuator cylinder with the actual pressure and forms a control variable for the electric motor. The control parameters are adapted in dependence on operating parameters, in particular in dependence on the pressure in the actuator cylinder. The control algorithm is preferably that of a PID control; however, it can also be that of a state control or fuzzy logic. The control parameters of the controller are to be selected accordingly to match the properties of the control path comprising, on the build of pressure, electric motor, pump, check valve, pressure cylinder and friction clutch. The adaptation takes the fact into account that the package stiffness of the whole clutch (in other words: the spring characteristic) is highly non-linear over the closing path of the clutch. It breaks down into three part regions having greatly differing gradients.
In a further development of the control algorithm on the build up of pressure (positive sign), it is that of a cascade controller, with a desired speed of the electric motor being determined in a first controller from the difference of the desired pressure and actual pressure in the actuator cylinder, a desired electrical parameter being determined in a second controller from the difference of the desired speed of rotation and the actual speed of rotation of the electric motor, and a control variable with which the electric motor is controlled being determined in a third controller from the difference of the desired electrical parameter and the actual electrical parameter.
The cascading has the following advantages: more favorable dynamics because the time constants of the individual controllers can be adapted to the respective time constants of the control path; better control elimination of variable disturbance due to the internal feedback; protection of the electric motor from overloading. A further improvement is achieved with the cascading in that the control parameters of the first controller are adapted in dependence on operating parameters, in particular on the pressure in the actuator cylinder. Instead of the adaptation, a plurality of controllers with different control parameters and a subsequent selection can also be used.
For the pressure reduction (negative sign), the control algorithm forms, in a first variant, a control variable for the electric motor by a comparison of the desired position of the slider of the fast drain valve with its actual position, with the desired position of the slider primarily being formed from the values of the desired pressure and the actual pressure in the actuator cylinder. In this connection, the actual position of the slider is determined from one or more operating parameters of the actuator, for instance from a parameter corresponding to the angle of rotation of the electric motor. The position of the fast drain valve can, however, also be measured.
For the pressure reduction (negative sign), the control algorithm forms, in a second variant, a control variable for the electric motor by a comparison of the desired gradient with the actual gradient of the pressure in the actuator cylinder, with the desired gradient being formed as a function of the desired pressure and the actual pressure in the actuator cylinder by a time derivation of the actual pressure in the actuator cylinder.
In a further development of the control algorithm on the reduction of pressure (negative sign), it is that of a cascade controller, with a desired speed of the electric motor being determined in a first controller from the difference of the desired position and the actual position of the electric motor, a desired electrical parameter being determined in a second controller from the difference of the desired speed of rotation and the actual speed of rotation of the electric motor, and a control variable with which the electric motor is controlled being determined in a third controller from the difference of the desired electrical parameter and the actual electrical parameter. The aforesaid advantages of a cascade control are also utilized again here.
In a further development of the method in accordance with the invention, special measures are also to be provided for the maintenance of the pressure in the actuator cylinder (when the sign of the difference of the desired pressure and actual pressure is within a predetermined tolerance). In a first variant, the control algorithm then monitors the actual pressure in the actuator cylinder and forms, with a defined pressure drop, a control variable for the electric motor which accelerates it from a reduced speed or sets it in motion when at a standstill. In a second variant, the control algorithm monitors the position of the slider and forms a control variable for the electric motor on a defined deviation occurring. In this connection, the control variable for the electric motor is the motor current. If the pressure in the actuator cylinder should be maintained, only the fast drain valve has to be kept closed. The pressure required for this is determined by the force of the spring acting on the slider and a specific motor current corresponds to this pressure.
The invention also relates to a system for the control of a hydraulic actuator of a friction clutch, said hydraulic actuator including the components listed in the preamble of the first claim, with the system containing a processor and a driver stage for the control of the electric motor. It is characterized in that the processor forms at least two controllers with different control behaviors and contains a selection logic which selects the output signal of the one or the other controller in dependence on whether the pressure in the actuator cylinder should be raised or lowered. This takes the fact into account that the control path in the two operating states has a different structure and behaves differently due to the interaction of the check valve and the fast drain valve. A specific pressure can thus both be set precisely and be lowered very fast again with an overall minimal consumption of electrical energy.
In a further development of the system in accordance with the invention, the one and/or the other controller is made as a cascade controller, with, in the cascade, a first controller comparing the respective control parameters with one another and forming a desired speed for the electric motor, a second controller comparing the desired speed with the actual speed of the electric motor and forming a desired electrical parameter, and a third controller comparing the desired electrical parameter with an actual electrical parameter and determining a control variable with which the electric motor is controlled. The advantages of the cascade control listed further above are thus achieved, with the increased effort on the implementation in a processor only consisting of additional measurement devices for the operating parameters fed back in the internal loops or with the measurement devices anyway being present.
The invention also relates to a friction clutch for the drivetrain of a motor vehicle comprising an actuator and which has a control system with the torque transmissible by the friction clutch being substantially proportional to the pressure in the actuator cylinder.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
FIG. 1 illustrates a scheme of the actuator in accordance with the invention with a friction clutch;
FIG. 2 is a block diagram of the control system in accordance with the invention;
FIG. 3 illustrates a scheme of the control for a positive sign;
FIG. 4 illustrates a variant of the controller of FIG. 3 ;
FIG. 5 illustrates a scheme of the controller for a negative sign in a first embodiment;
FIG. 6 illustrates a variant of the controller of FIG. 5 ;
FIG. 7 illustrates a scheme of the controller for a negative sign in a second embodiment.
DETAILED DESCRIPTION
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
In FIG. 1 , a cylinder in piston unit is designated in summary by 1 , a valve unit by 2 and an electric motor and pump unit by 3 . A pressure space 4 is present in the cylinder in piston unit 1 and is in communication via a line 6 with the valve unit 2 , with the pressure fluid contained in the pressure space 4 acting on a piston 5 . This piston 5 is part of a friction clutch 7 or is directly in communication therewith. The friction clutch 7 is only indicated since it is of the usual construction with disks and a spring. In the friction clutch 7 , the pressure exerted by the piston 5 acts against the force of this spring and of the clutch disks. As the pressure increases, the torque transmissible by the clutch increases approximately proportionally with the pressure.
The valve unit 2 contains a fast drain valve 8 and a check valve 9 . The latter has a ball 9 ′ pressed toward a seat by a spring 9 ″. The fast drain valve 8 is formed by a socket 10 having at least one opening 11 , which opening is in communication with the pressure space 4 via the line 6 , and by a piston 12 displaceable in the socket 10 . The piston 12 separates a first space 13 containing a compression spring 14 from a second space 17 . The first space 13 is in communication via a drain line 15 with a sump 16 from which the electric motor and pump unit 3 sucks in fluid and into which it pumps fluid. A pressure line 18 is connected to the second space 17 and in turn establishes the connection between the electric motor and pump unit 3 and to the pressure space 4 via the check valve 9 .
The electric motor and pump unit 3 comprises a pump for the pressure fluid and a motor 20 which is controlled by a control system 21 . In the embodiment described, a permanently excited DC motor is used. As the input signal, the control system 21 receives actual values determined by sensors 22 (only a pressure sensor is indicated here) and, via a line 23 , a desired value of a pressure in the actuator cylinder which generates the contact pressure acting on the disks of the clutch 7 and corresponds to the maximum torque to be transmitted by the clutch. The previously described elements form the actuator of the clutch 7 .
The manner of operation of the described arrangement is as follows: In the position shown in FIG. 1 , the electric motor and pump unit 3 either does not pump at all or at a pressure which is not sufficient to open the check valve 9 or to close the fast drain valve 8 . No pressure is present in the pressure space 4 ; the clutch, which is not shown, is thus not acted on, that is does not transmit any torque. If the pressure of the pressure medium in the line 18 delivered by the pump 19 now increases, this acts in the second space 17 on the lower side of the slider 12 made as a piston against the force of the spring 14 . At a specific pressure, the slider 12 starts to move upwardly, with it closing the opening 11 and thus the outflow from the pressure space 4 . Only when the opening 11 is fully closed does the check valve 9 open and can pressure fluid flow into the pressure space 4 and control the clutch accordingly.
If the pump 19 is now stopped, the pressure acting on the slider 12 drops; the check valve 9 closes at the same time. The slider 12 is slowly pressed downwardly by the spring 14 (depending on the leakage of the pump), whereby the openings 11 become free again after a specific time and the pressure fluid can escape from the pressure space 4 into the sump 16 . If the electric motor and pump unit 3 is now switched over such that the pumping direction also reverses, that is the pump 19 pumps out of the pressure line 18 into the sump 16 , an underpressure arises under the slider 12 and substantially accelerates its downward movement. Then, on switching over of the motor 20 , the clutch is fully opened for a moment as is required, for example, in the case of ABS braking.
If the pressure space 4 is under pressure and the electric motor and pump unit 3 maintains the fast drain valve closed, the pressure continues to be maintained for a while with a good seal. This means that, in steady state operation with an engaged clutch, the electric motor and pump unit 3 only has to maintain the pressure for the slider to remain closed. The output amount is almost zero since leakage mainly takes place in the interior of the pump. A substantial saving in energy is thus achieved.
In FIG. 2 , the total control system 21 is shown as part of a feedback control circuit which it forms with an actuator and its control path which are here indicated together and designated by 28 . Various sensors are attached to the actuator and to the control path and generate signals 22 , and indeed:
22 a : actual pressure (p act ) in the actuator cylinder 4 ; 22 b : actual current strength (I act ) of the current supplied to the electric motor 20 ; 22 c : actual voltage (U act ) of the current supplied to the motor 20 ; 22 d : actual angle of rotation of the motor 20 ; 22 e : actual speed of the motor 20 , 22 f : the actual position (x act ) of the slider 12 ; 22 g : the position of the actuator piston 5 ; 22 h : a signal corresponding to the pressure signal (for example, determined from other signals, for instance from a torque signal or rotational speed signal).
The actual pressure signal 22 a or 22 h in any case and individual ones of the further signals 22 b to 22 g are available to the control system 21 , in the same way as a signal 23 which is emitted by a higher level control system, which indicates the desired pressure (p des ) in the actuator cylinder 4 and which is substantially proportional to the maximum torque to be transmitted by the clutch.
The control system 21 comprises in general terms an analog/digital converter 25 which makes the signals 22 and 23 available to a computing unit 26 in digital form. The latter's output signal 36 is a control variable for the motor 20 which is supplied to a driver stage 27 which controls electrical current supplied to the electric motor with respect to voltage and/or current strength. The input signal 23 can already be present in digital form and also additionally contain the width of the tolerance range.
Three controllers 30 , 31 , 32 and a selection logic 33 are provided in the computing unit 26 . All three are arranged in parallel, they receive, as input parameters, the desired pressure 23 (p des ) and the measured signals 22 , but at least the actual pressure 22 a or 22 h , and all three controllers provide, as the output signal, a control variable 34 a , 34 b , 34 c for the electric motor 20 , from which the selection logic 33 selects a signal 36 , likewise in dependence on the desired pressure 23 (p des ) and the measured signals 22 , but at least on that of the actual pressure 22 a or 22 h (p act ). The three controllers 30 , 31 , 32 connected in parallel come into effect, only one in each case, in different control situations. The first controller 30 , when the desired pressure 23 (p des ) is larger than the actual pressure 22 a or 22 h (p act ), that is when the pressure should increase in the actuator cylinder (and the clutch should be engaged). The sign of the pressure difference designates its preceding sign, which is positive in this case. The second controller 31 acts when the pressure difference, and thus the sign, is negative, which corresponds to a dropping pressure in the actuator cylinder (and a disengagement of the clutch). Finally, a third controller can be provided to maintain the pressure. It acts when the desired pressure and the actual pressure are within the preset tolerance. It is also called a maintaining controller. The control variable 36 for the motor 20 selected by the selection logic 33 is forwarded to the driver stage 27 .
In FIG. 3 , the first controller 30 comprises the actual controller 37 and a computer 38 for the calculation of the control parameters on the basis of individual input signals 22 , in particular, but not exclusively, of the actual pressure signal 22 a or 22 h . The control parameters calculated by it (with a PID controller, that is the factors determining the P, I and D functions) are provided to the actual controller 37 for adaptation. The controller 30 is thus adaptive overall. This takes into account the fact that the relationship between the pressure to be overcome by the actuator piston ( 5 ) (comprising the force of the clutch springs and the contact pressure of the clutch disks required for the transmission of a specific torque) and its path is strongly non-linear. Without the adaptation function, the positioning procedure in the range of low force would take much too long. The factors describing the controller (P, I, and D factors) are therefore set in accordance with the input signals 22 and 23 , in particular in accordance with the actual pressure 22 a , 22 h , such that the adjustment of the piston 5 corresponds to the demands on the dynamics in all ranges. The parameters determined by the computer 38 are forwarded to the actual controller 37 via the connection 39 .
When a controller, a connection or a loop are spoken of in the total description, a program module is meant, when a processor is used, which carries out the corresponding control algorithm.
In the variant of FIG. 4 , the controller 30 ′ is made as a cascade controller which comprises three sub-controllers 40 , 43 , 45 which are connected in cascade. The first sub-controller 40 is divided into three regions 40 ′, 40 ″, 40 ″′ with different control parameters, as an alternative solution to the adaptive controller 30 of FIG. 3 . It is followed by a selection logic 41 which, like the input of the controller 40 , receives the actual pressure signal (p act ) via the “line” 42 ; it ( 42 ) forms an outer return loop of the cascade. The output signal of the first sub-controller controller 40 is a desired speed of the motor (n des ). The second sub-controller 43 of the cascade is a speed controller to which the desired speed signal (n des ) of the first sub-controller 40 and, via a middle return loop 44 , an actual speed of rotation (n act ) of the motor is supplied. The output signal is a desired current signal (I des ) for the motor. It is compared in the third sub-controller 45 with the actual current (I act ) of the motor and generates a control variable 34 a for the motor 20 . The actuator and the control path 28 are indicated.
FIG. 5 shows the second controller 31 for a negative sign (pressure drop) in a first embodiment. An actual value 22 f (x act ) corresponding to the actual position of the slider 12 and a desired value of the position of the slider 12 (x des ) are supplied to the actual controller 50 . Said desired value is primarily calculated from the desired pressure 23 (p des ) in the actuator cylinder and from the actual pressure signal 22 a or 22 h (p act ). Further measured signals 22 can be supplied to the controller via the loop 52 . The output signal 34 of the actual controller 50 is in turn a control variable 34 b for the electric motor.
In the variant of FIG. 6 , the controller 31 for a negative sign is again made as a cascade controller. The computing unit 60 determines the desired position of the slider 12 (x des ) from the actual pressure 22 a or 22 h (p act ) and the desired pressure 23 (p des ) in the actuator cylinder 4 , with the desired value (x des ) of the position of the slider 12 being a function of the throughflow cross-section of the opening 11 . In a first sub-controller 63 , a desired speed of the motor (n des ) is determined from the desired value (x des ) of the position of the slider 12 and from its actual value (x act ), which is determined in a computing unit 61 from the signals 22 , preferably from the actual angle of rotation 22 d , actual speed of rotation (n act ) of the motor. The actual position (x act ) of the slider 12 is supplied to the first sub-controller 63 (a position controller) via an external return loop 62 . In a second sub-controller 65 (a speed controller), a desired current (I des ) for the motor is calculated from the desired speed of rotation (n des ) of the motor and an actual speed of rotation (n act ) of the motor communicated via a middle return loop 64 . This desired current (I des ) is in turn compared with the actual current (I act ) supplied via an internal return loop 66 and a control variable 34 b for the electric motor is determined from this in a third sub-controller 67 (a current controller).
FIG. 7 shows a second embodiment of the second controller 31 (negative sign) which differs from that of FIG. 5 in that, instead of the desired position (x des ) of the slider 12 , the pressure gradient (dp/dt) is used as the input parameter. The actual controller 70 compares a desired value (dp/dt des ) of the pressure gradient with an actual value (dp/dt act ) of the pressure gradient. The first is calculated in a computing unit 71 from the desired pressure 23 (p des ) and the actual pressure 22 a or 22 h (p act ) in the actuator cylinder 4 . The second is determined in a unit 72 from the actual pressure signal 22 a or 22 h (p act ). The output value is again the control variable 34 b for the electric motor.
The description is merely exemplary in nature and, thus, variations that do not depart from the gist of the present disclosure are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure.
|
A method of controlling a hydraulic actuator of a friction coupling that includes a pump, which is driven by an electric motor, a pressure line, which contains a non-return valve and which runs from the pump to an actuator cylinder with an actuator piston that acts on the friction coupling. A rapid drain valve has a flow connection to the actuator cylinder and contains a slide that responds to the pressure prevailing on the side of the pump that faces the slide. To optimize the dynamic and static control behavior of the actuator, a control variable is determined for the electric motor from the target pressure and the actual pressure in the actuator cylinder. At least two different control algorithms are executed, depending on whether the difference between the target pressure and the actual pressure is positive or negative.
| 5
|
TECHNICAL FIELD
[0001] The invention relates to a device for actuating double seat valves, especially for the food and beverage industry, according to the preamble of Claim 1 .
PRIOR ART
[0002] A device according to this generic type is known from EP 0 868 619 B1. The device diagrammed in FIG. 6 and explained briefly in the attached description is in fact not subject matter of the patent claims of this publication, however the features disclosed prove how through simple modification to the protected actuating device 1 (reference numbers of the figures therein) a double seat valve can be activated, whose independently actuated first closing element 4 is designed as a sliding piston with radial sealant and whose dependently actuated second closing element 5 is designed as a seat disc. In this closing element configuration the partially open position T 1 of the first closing element 4 is completed in the opposite direction to the opening stroke H, which is directed upwards relative to the diagrammed position of the valve. For execution of the partially open position T 1 a main piston 106 of the main adjustment device 1 a is loaded from above with pressurizing medium D 2 using a non-specified pressurizing medium connection. The partial stroke limit downwards of the first closing element 4 occurs in that a valve stem 104 takes its bearing on the latter through a non-specified recess above a spring abutment 119 . The partially open position T 2 of the attached actuated second closing element 5 , which only has a freedom of motion upwards due to its design as a seat disc, is done using a piston 108 , which is loaded with pressurizing medium D 3 using a first pressurizing medium connection 117 . The synchronization of a hollow bar 105 connected with the second closing element 5 upwards is done using its hollow bar head 105 a . The partial stroke limit of the piston 108 is implemented through a second recess 114 a on the stop sleeve 114 .
[0003] The preceding briefly described actuator is also designated in expert circles as a so-called “integrated” actuator, because it accommodates the main adjustment device 1 a for the full opening stroke H as well as the individual adjustment devices 1 b, 1 c for the partially open positions T 1 and T 2 in a common housing. These types of actuators are as a rule compactly built and make it possible to arrange a so-called control module and/or control head 8 ( FIG. 1 ) directly above the main adjustment device 1 a, if the individual adjustment devices 1 b, 1 c are arranged in the previously described manner in reference to the main adjustment device 1 a.
[0004] The significant disadvantages of the integrated actuators arise also from the fact that they are designed for the maximum requirements which are placed on double seat valves of the type under discussion. Maximum requirements are then given if, along with the full opening stroke H which is executed by the main adjustment device, the opposed partially open positions T 1 , T 2 of both closing elements for the execution of the respective seat cleaning, which is carried out by an individual adjustment device assigned to each closing element to be activated, are necessary. Since a large portion of the double seat valves placed in installations in the food and beverage industry are in applications without the possibility or necessity of seat cleaning, because only mixing efficiency is required, integrated actuators in which only the main adjustment device is activated are normally too complex and therefore uneconomical. In practice these types of applications then fall back on “normal” actuators (standard actuators) for double seat valves, which only accommodate a main adjustment device for the full open position H. Thereby the number of integrated actuators from a manufacturer of double seat valves is reduced, since each double seat valve corresponding to the requested requirements is at best equipped with a suitable actuator for this purpose and thereby results in an uneconomical number of manufactured integrated actuators as the case may be.
[0005] A further integrated actuator for a double seat valve according to this generic type is known from the EP 1 030 988 B1. The kinematics of this actuator corresponds in an identical manner to that according to FIG. 6 in the EP 0 868 619 B1. In contrast to the latter, in the former the partial stroke movement T 1 opposed to the full opening movement H of the independently actuated first closing element which is designed as a sliding piston is executed by a separate third working piston 30 , which is arranged above the first working piston 18 , which causes the full opening stroke H. The general arrangement is therefore in fact more complex, however by the separate third pressure chamber 39 created over the third working piston 30 the necessary volume for its loading with pressurizing medium is significantly reduced compared to the corresponding pressure chamber over the main piston in actuation of the double seat valve according to EP 0 868 619 B1, whereby less pressurizing medium is used when switching the assigned partial stroke movement T 1 and the actuation reacts quicker to the switching command in this regard. At the same time the integrated actuator according to EP 1 030 988 B1 is in turn also relatively complexly constructed and flawed with the preceding briefly presented further disadvantages in connection with the integrated actuator according to EP 0 868 619 B1.
[0006] In DE 31 33 273 C2 it was already proposed for a cleanable double seat valve with leakage control, to additively insert the individual adjustment devices between the main adjustment device and a lantern housing under the main adjustment device which exclusively creates the full stroke for the full open position as the only adjustment device without changing the neighboring standard member. However it is concerned here with a double seat valve, which has two closing elements designed as seat discs, so that the full stroke H for the full open position and both partial stroke movements T 1 , T 2 are aligned for gapwise removal of the closing elements from their respective seat surfaces. These attainable advantages with this so-called “modular” actuator concept especially exist in that to the greatest possible extent a standardized double seat valve, which has available a standard actuator for the creation of the fully open position through additive of relatively simple individual adjustment devices, contains special functions in regards to the previously described creation of partially open positions of both closing elements. From DE 31 33 273 C2 there are no details to be taken on whether the known modular actuator concept is applicable to double seat valves of the preliminary characterized type and not at all what this type of solution could look like.
[0007] The dependently actuated closing element of the double seat valve, which is also designated as a double disk with its two seals, is in fact not critical during the seat cleaning in regards to its partially open position T 2 and can therefore be moved against a fixed stop for the execution of the aligned seat cleaning position. This stop therefore needs no complex pre-adjustment or readjustment. During the seat cleaning the cleaning solution is normally under pressure on the dependently actuated closing element, so that this must be opened by the partial stroke T 2 against the resulting closing force from the corresponding pressure and the assigned effective surface of this closing element. To overcome this closing force or holding down force the assigned second individual adjustment device is to be dimensioned accordingly. Either a sufficiently large piston surface of the actuating piston in this second individual adjustment device is to be provided or the pressure of the pressurizing medium loaded on the actuating piston is to be correspondingly increased if there are restrictions in regards to the dimension of the diameter of the actuating piston. An adjustment of the actuator to the existing pressure conditions using a corresponding dimensioning of the actuating piston is always primarily a question of cost and is normally only chosen if other possibilities are not available. The choice of a higher pressure of the pressurizing medium is normally preferred; it is however always eliminated in practice if the installation or plant in which the cleanable double seat valve is installed does not have a pressure level available in this regard or out of cost considerations can not be additionally done.
[0008] It is the object of the present invention to design a device according to this generic type in such a manner that it is constructed as simply as possible and is easily and economically adjustable to the various requirements which are put onto a double seat valve of the type in discussion (only full opening stroke or full opening stroke as well as seat cleaning partial strokes).
[0009] Furthermore in the scope of an advantageous embodiment of the proposed device a larger flexibility should be ensured in the adjustment of the second individual adjustment device for the partial stroke movement of the dependently actuated closing element on the available pressure of the pressurized medium.
SUMMARY OF THE INVENTION
[0010] The object is solved by the features of Claim 1 . Advantageous embodiments of the proposed device are the subject matter of the subclaims.
[0011] One obvious first advantage of the proposed solution lies in that for the first time a solution is disclosed on how the motion kinematics of a double seat valve capable of seat cleaning of the type in discussion with a modular actuator concept is implemented, in which the main adjustment device has a standard actuator and the individual adjustment devices are independently designed and are inserted between the standard actuator and the valve housing or a lantern housing connected with it. For that reason henceforth it is possible to equip double seat valves which are capable of seat cleaning and those that are not capable of seat cleaning with the same standard actuator for the full opening movement of the valve. Thus on the one hand the best conditions for an economic number of production pieces of this type of standard actuators prevail and on the other hand for each double seat valve only the corresponding necessary actuator parts are used.
[0012] Furthermore the proposal makes possible the implementation of special functions, namely the execution of the partial stroke movement T 1 , T 2 of both closing elements for the purpose of their seat cleaning by means of stand-alone individual adjustment devices, economically justifiable for initial equipment of double seat valves, as well as for the refitting of already available double seat valves, which were previously normal switching, however more capable of seat cleaning.
[0013] The insertion of stand-alone individual adjustment devices in a relatively complex structure, as is demonstrated in a double seat valve, is therefore possible because the individual members within the scope of a modular system are normed or standardized in their connections and joints as far as possible. This is true for the main adjustment device (standard actuator) as well as for the lantern housing adjacent to the valve housing and the control rods led through from the upper valve housing member. The housing connection is done preferably using standardized so-called clamping ring connections and the control rods are screwed together at the corresponding locations. Due to the arrangement of the individual adjustment devices between the main adjustment device and the valve housing, the other side of the main adjustment device remains free for the arrangement of a control device, which among other things monitors the path of motion and the discrete end locations of the closing elements and takes over the entire control logic as well as the pilot valve.
[0014] A further advantage results from the axial decoupling of the first valve stem, which extends into the area of the individual adjustment devices in a second actuator stem, connected with the independently actuated first closing element or from the corresponding decoupling of the second actuating piston permanently axially connected with the first valve stem from a first actuator stem which is arranged in the main adjustment device and at the same time reaches into the area of the individual adjustment devices. The partial stroke movement T 1 of the independently actuated, first closing element which is designed as a sliding piston opposite to the full opening stroke H of the valve is first possible by this decoupling.
[0015] On the other hand it allows the first executable axially movable positioning of the second actuating piston by the previously named uncoupling onto the first actuator stem, this if needed, namely with the full opening movement to push in the direction of this opening movement so far on the bearing location until it arrives in a clamping connection. In this clamping connection the second actuating piston supports from now on the main adjustment device in the opening stroke H, since the second actuating piston according to the invention is able to be loaded with pressurizing medium on each of its two piston surfaces and through this can make an additional independent opening force available in the direction of the full opening movement of the double seat valve. The second actuating piston and with it the assigned individual adjustment devices thus have the function of a so-called “batch actuator” in this movement phase of the actuating.
[0016] The special actuating kinematics of the proposed device lies in that the force flow from the second actuating piston can act through the first actuator stem and the first actuating piston onto the prestress force of the main spring. Conversely however it is not possible through the axial decoupling between the main adjustment device and the individual adjustment devices, to transfer an opening force to the first closing element from the main adjustment device. An opening of the double seat valve alone with the help of the main adjustment device is therefore not possible. It is mandatory for the opening of the double seat valve to always be done according to specifications through the stroke movement of the first actuating piston, but only then when the second actuating piston of the first actuator stem in the main adjustment device follows in the corresponding force supporting trailing action.
[0017] Since the second actuating piston, not in a necessary but desirable manner, has approximately the same piston cross-section as the first actuating piston in the main adjustment device, the possibility arises through the aforementioned batch function to significantly reduce the size of the main adjustment device relevant to the opening force (this is primarily the diameter), whereby among other things a significant cost reduction takes place. On the other hand from the aforementioned circumstances the possibility arises to actuate the double seat valve without reduction of the size ratio of the actuator even with a low operating pressure of the pressurized medium.
[0018] Both stand-alone individual adjustment devices are built space-saving and compact, if they, as it is proposed, are arranged in a single housing designed from two housing members and with their actuating pistons there form three pressurizing medium chambers actuating independently of one another, whereby the second pressurizing medium chamber between the second actuating piston and the third housing member, the third pressurizing medium chamber between the third actuating piston and the fourth housing member and the fourth pressurizing medium chamber between both of the two actuating pistons form the individual adjustment devices.
[0019] If, as this is further proposed, the first actuator stem of the main adjustment device leads out through the latter in the direction of the individual adjustment devices and is guided axially movable there in the front end of the second actuator stem which is permanently connected to the first control rod up to a stop face, then it is possible to make the second actuating piston out of corrosion resistant light alloy, preferably out of aluminum. This would furthermore be proposed for the other actuating pistons as well, due to cost and weight saving reasons.
[0020] For easier adjustment of the actuator of the second individual adjustment device, which is assigned to implement the partial stroke T 2 for the dependently actuated closing element, a different, however above all relatively low pressure of the pressurized medium provides a further embodiment of the proposed device, that the third actuating piston is fixed, however able to be loosened, on its side toward the second actuating piston with a smaller diameter additional piston, that the additional piston working together with a housing ring fixed on the housing of the individual adjustment devices forms a fifth pressurizing medium chamber, which is connected with a third pressurizing medium chamber formed between the third actuating piston and the fourth housing member, and that with the introduction of a third pressurizing medium flow to the third pressurizing medium chamber also additionally in the fifth pressurizing medium chamber an additional force results affecting the additional piston, which additively superimposes on the force affecting the third actuating piston. Through the arrangement of an additional piston on the actuating piston of the second individual adjustment device the latter gains a function, which is also often designated as a so-called “batch function”. The actuating piston experiences quasi a surface enlargement through the additional piston, which indeed does not have the effect of a larger diameter piston surface by the chosen arrangement, but rather is found in a second, parallel plane. In the present case the pressurizing medium reaches the actuating piston first and finally the additional piston, in order each time to develop a force on the respectively arranged pistons through the installed piston surfaces, whereby these two forces, the force on the actuator pistons and the additional force on the additional pistons are additively superimposed on each other.
[0021] A compact arrangement of the second individual adjustment device with additional pistons is attained according to a further proposal, in that the additional piston has a larger diameter external piston section and a smaller diameter interior piston section, that the interior piston section is sealed on the face side against the third actuating piston and bolted to it, that the exterior piston section is sealed on the circumference against the shell of a cylindrical cutout in the housing ring and the interior piston section is sealed on the circumference in a coaxial through-bore in the housing ring, and that in the connection area of the third actuating piston with the additional piston are arranged in the former a first pressurizing medium channel and in the latter a second pressurizing medium channel, which correspond with one another and connect the third pressurizing medium chamber and the fifth pressurizing medium chamber with one another permeable to the pressurizing medium. The housing ring which is fixed in the housing of the individual adjustment devices forms on the one hand, with the additional pistons, the necessary additional fifth pressurizing medium chamber and creates on the other hand through its housing side support, the physical conditions for the addition of the additional force to the force on the third actuating piston. The latter borders the third pressurizing medium chamber in connection with the fourth housing member, in which the third pressurizing medium flow is first introduced in order to then finally reach into the fifth pressurizing medium chamber.
[0022] According to a further advantageous embodiment the housing ring has a radial projection on the circumferential side, with which the housing ring is arranged form fit to the connection area between the third and the fourth housing member. The assembly of the housing ring is simple under these conditions, since the latter is inserted in the third and the fourth housing member, before these are then connected with one another, preferably integrally joined. It shall be understood that also a detachable connection between the third and the fourth housing member can be made.
[0023] The device according to the invention is designed either with or without additional pistons. Since it is an advantage for the housing of the individual adjustment devices with the pressurizing medium connection which comes into question to always be designed identically regardless of whether an additional piston is present or not, a further embodiment of the proposed device is designed, that a fourth pressurizing medium connection for an alternative first pressurizing medium flow for loading the second actuating piston which is arranged in the third housing member discharges into an upstream fourth pressurizing medium chamber in the area between the third actuating piston and the housing ring, and that the upstream fourth pressurizing medium chamber is connected with a fourth pressurizing medium chamber designed between the second actuating piston on the one hand and the housing ring in connection with the additional piston on the other hand through at least one connection channel, which is arranged in one of the cylindrical cutout outside encompassing part of the housing ring. Through this arrangement the fourth pressurizing medium connection can remain on any position in the housing of the individual adjustment devices on which it is arranged if the second individual adjustment device is not equipped with an additional piston. The connection channel in the housing ring ensures the permeability for the pressurizing medium, so that the pressurizing medium introduced through the fourth pressurizing medium connection can get from one side of the housing ring to its other side under the second actuating piston.
[0024] The relatively simply designed total actuator, which experiences a clearly functional separation through its modular design, is relatively unproblematic in regards to adding additional manufacturing tolerances of its individual members, since the closing elements each open in their respective seat cleaning positions non-critical in the arranged valve housing members and therefore danger of collision in the process of the partially open positions T 1 , T 2 do not exist. For this reason the proposed device needs no adjustable stops for limiting the respective partial stroke movements of the closing elements in the process of their seat cleaning, rather there are conceivable simple end-of-travel limit stops. In this regard a proposal is envisaged that the end-of-travel limit stops of the second actuating piston for the first partially open position T 1 and that of the third actuating piston for the second partially open position T 2 are done by a stop-ring or housing ring arranged permanently between the actuating piston and axially movable on both sides.
[0025] It is further proposed that the fourth pressurizing medium chamber is connected according to the stream with a first pressurizing medium connection, which is equipped on a control device arranged in the connection to the main adjustment device. Since according to an advantageous embodiment this connection is done within the main adjustment and the individual adjustment devices, in this way the first pressurizing medium chamber of the main adjustment device can also be supplied with pressurizing medium, so that external pressurizing medium connections for controlling the full opening stroke H are not necessary either on the main adjustment device nor on the housing of the individual adjustment device.
[0026] Nevertheless a further embodiment is allowed for, alternative to the preceding proposed solution, to provide the fourth pressurizing medium chamber with a fourth pressurizing medium connection, which is designed to be on the housing of the individual adjustment devices. Through retention of the internal connection lines between the first and the fourth pressurizing medium chamber there exists an additional possibility for control with this solution, to activate the full opening stroke of the double seat valve over this external fourth pressurizing medium connection, whereby the first pressurizing medium connection on the control device is then omitted or can be blinded.
[0027] Along with the axial decoupling of the first valve stem or the second actuating piston from the first actuator stem in the main adjustment device there is a further advantageous embodiment allowed for, to additionally put into effect a rotating decoupling between the aforementioned members at this decoupling location. As is generally known in the axial deformation of a helical spring, as is provided as the main spring in the main adjustment device, considerable torsional moments are transferred from the spring onto its abutment, in this case on the first actuating piston loaded from this and therefore on the first actuator stem. These torsional moments can cause loosening of the actuator stems and adjustment rods which are bolted together. Through the proposed rotating decoupling between the main and the individual adjustment devices the aforementioned rotation on the first actuator stem remains limited; a transfer of a torque on other members in the area of the individual adjustment devices and the double seat valve is impossible.
[0028] The rotating decoupling proves to be especially advantageous if, according to a further proposal, the frontal end of the first actuator stem has a header, which engages into a cutout within one of the headpieces that is formed onto the second actuator stem and that has a larger diameter compared to it. The sliding conditions are thereby improved in that a plain bearing bush is placed between the header and the cutout.
[0029] In order to be able to realize the axial position of the independently actuated first closing element even after the axial decoupling of the first actuator stem in the control device, according to a further proposal a position indicator rod is provided, which each time concentrically penetrates the first actuator stem completely and the second actuator stem to the first control rod, which on the one side ends in a control device and on the other side is screwed with its frontal end in the second actuator stem and thereby counter secures the screw connection between the adjustment rod and the actuator stem on a first end surface of the first control rod with its arranged second end surface. The proposed jam nut makes difficult or prevents loosening of the screw connection between the first control rod and the second actuator stem in the area of the second individual adjustment device.
[0030] The ring channel, which is designed between the position indicator rod on the interior and the first actuator stem, the header, the headpiece and the second actuator stem each on the exterior, is advantageously used as a route of transport for the pressurizing medium to the first pressurizing medium chamber, as well as to the fourth pressurizing medium chamber, whereby the distribution of the pressurizing medium in these spaces is done with the appropriate cross holes.
[0031] Through the preceding described batch function of the first individual adjustment device working together with the main adjustment device designated for the generation of the full opening stroke H, a reduction of the diameter size of the main adjustment device is possible, so that the housing of the main adjustment device and that of the individual adjustment devices can be implicitly designed with the same diameter, whereby according to the requirements the latter must bring a lower actuating force than the main adjustment device. Thereby it is again possible, as a further proposal shows, to make the housing members of the main adjustment device and those of the individual adjustment devices from housing rough parts of the same shape, whereby a further cost reduction results.
[0032] The manufacturing costs can be further reduced in that the housing members of the main adjustment device and those of the individual adjustment device are each integrally joined together, preferably through welding. It is understood that the housing members coming into question can also be connected with each other in a detachable manner.
[0033] Overall it has been shown that the proposed device for actuating double seat valves, is realized first of all with a so-called modular actuating concept and secondly, further cost reducing actions were proposed compared to the known so-called integrated actuating leading to a significant reduction of the manufacturing costs which amounts to half of the previous costs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] Exemplary embodiments of the proposed device for actuating double seat valves according to the invention are represented in the drawing and are described following according to design and function, wherein:
[0035] FIG. 1 shows a middle cross-section through a first embodiment of a device for actuating double seat valves of the generic type according to the invention, whereby the referenced double seat valve in the closed position in this reference is arranged below the proposed device and a control device (in broken-out section) is arranged above it.
[0036] FIG. 2 shows a middle cross-section through the device according to FIG. 1 , whereby the illustrated device represents the position of the movement dependent members so that these correspond to the closed position of the two closing elements which are represented in the lower area of the illustration in sections.
[0037] FIG. 3 also shows a device in middle cross-section and both arranged closing elements according to FIG. 2 , whereby the members of the device coming into question henceforth are found in one of the corresponding locations of the full open positions of the two closing elements;
[0038] FIG. 4 also shows the device in middle cross-section and both arranged closing elements according to FIG. 2 , whereby the members of the device coming into question henceforth are found in one of the corresponding location of the seat cleaning positions of the first closing element designed as a sliding piston and
[0039] FIG. 5 also shows in middle cross-section the device and both arranged closing elements according to FIG. 2 , whereby the parts of the device coming into question henceforth are found in one of the corresponding locations of the seat cleaning positions of the second closing element designed as a seat disc;
[0040] FIG. 6 a middle cross-section through a second embodiment of the individual adjustment devices according to the invention, whereby the third actuating piston is connected with an additional piston and thus the arranged second individual adjustment device supports a so-called “batch function” and
[0041] FIG. 6 a a section from the individual adjustment devices according to FIG. 6 in the area of the screw connection between the third actuating piston and the additional piston.
DETAILED DESCRIPTION
[0042] The proposed device 100 , 200 ( FIG. 1 ) is used for actuating a double seat valve, that is essentially made up of a valve housing 1 with a first and a second valve housing member 1 a or 1 b, two closing elements 2 and 4 which move independently to each other using the arranged adjustment rods 3 a or 4 a in each case, a seat ring 2 which makes a connection between the valve housing members 1 a, 1 b using its inner connection orifice 2 c , a lantern housing 6 connecting the second valve housing member 1 b with the device 100 , 200 , as well as a control device 7 , whereby the latter is arranged on the side of the device 100 , 200 opposite to the double seat valve.
[0043] The independently actuated, first closing element 3 designed as a sliding piston is equipped on the circumference with a first seat seal 8 working exclusively in the radial direction, which is attached to a first seat surface 2 a ( FIG. 2 ), which is formed from the cylindrical surface in the seat ring 2 which borders the connection orifice 2 c . The dependently actuated second closing element 4 designed as a seat disc has in its seat area a second seat seal 9 which works in both the radial and axial direction, and which works together on the second seat surface 2 b also designed on seat ring 2 . Between the two closing elements 3 , 4 a leakage chamber 5 is formed which in the fully open position H of the double seat valve ( FIG. 3 ) is sealed against its environment by means of a seal 10 working exclusively in the axial direction, which is arranged on the end surface of the second closing element 4 facing the leakage chamber 5 .
[0044] The leakage chamber 5 , as well as the adjacent parts impinged by the flow, can be cleaned in the closed as well as in the open position of the double seat valve (see also FIGS. 2, 3 along with FIG. 1 ) by means of a cleaning solution R which is introduced through a cleaning solution connection 11 which is arranged in the area of the lantern housing 6 on the second control rod 41 , preferably a non-specified ring channel, between the first and the second control rods 3 a , 4 a . The removal of this type of “externally” introduced cleaning solution R from the leakage chamber 5 is done here by a non-specified connection line which is arranged in a tubular extension leading through the first valve housing part 1 a and out of it on the first closing element 3 .
[0045] The removal of an “internally” introduced cleaning solution by a particular seat cleaning stream R 1 , R 2 from the internal chamber 5 , which is introduced from the valve housing part 1 a or 1 b assigned at any one time during the seat cleaning of the first or the second closing element 3 , 4 (also see for this FIGS. 4 and 5 ), is done in the same manner as with the external cleaning introduction R. In the seat cleaning of the first closing element 3 , which is designed as a sliding piston, this is pushed so far in the direction of the first valve housing member 1 a ( FIG. 4 ), that a first partially open position T 1 consequently occurs, in which the first seat seal 8 has left the assigned first seat surface 2 a and the first seat cleaning stream R 1 from the first valve housing member 1 a is generated over the exposed first seat surface 2 a in the leakage chamber 5 .
[0046] For seat cleaning of the second closing element 4 , which is designed as a seat disc, this is pushed so far in the direction of the second valve housing member 1 b ( FIG. 5 ), that in a thus partially open position T 2 taken from the second closing element 4 , the second seat seal 9 left the assigned second seat surface 2 b and the second seat cleaning stream R 2 from the second valve housing member 1 b arrives into the leakage chamber 5 on the way over the exposed seat surface 2 b.
[0047] To limit the amount of cleaning solution in each of the seat cleaning streams R 1 , R 2 during the seat cleaning, if necessary known cylindrical projections are provided on the closing elements 3 , 4 , oriented toward the leakage chamber 5 , which during gapwise removal of the closing elements 3 , 4 from their assigned seat surfaces 2 a , 2 b still reaches sufficiently far with radial clearance into the connection orifice 2 c with the respective cylindrical projection and there in each case forming a so-called choking annular gap. Alternatively the limit of the seat cleaning streams R 1 , R 2 are thus also reached in that the particular partial stroke is not stationary generated, but rather oscillating.
[0048] To put into effect the preceding briefly illustrated switch movement of the closing elements 3 , 4 (full opening stroke H, partially open positions T 1 and T 2 ) hence-forth the double seat valve is equipped with the device 100 , 200 according to the invention, which has the main adjustment device 100 for the opening and closing of the double seat valve within the scope of the full opening stroke H ( FIG. 1 ) and the individual adjustment devices 200 for the generation of the partially open positions T 1 , T 2 . The main adjustment device 100 corresponds in its design to a so-called standard actuator, with which a double seat valve of the type in question can be opened and closed on its own; Special functions, such as seat cleaning, cannot be done with this standard actuator. The main adjustment device 100 is designed in a manner in regards to its peripheral housing connections and other necessary connections, so that when eliminating the individual adjustment devices 200 it can be directly connected with a lantern housing 6 , which is in fact adjusted in length but is otherwise not changed. The end (male threads) of the first control rod 3 a is in this regard designed in such a way, that it is complementary to an end section (female threads) of a second actuator stem 203 of the individual adjustment device 200 , as well as is complementary to an end section of a first actuator stem 103 of the main adjustment device 100 , with which it is screwed in each case, if necessary. The second control rod 4 a continues on above the cleaning solution connection 11 in a third actuator stem 204 designed as a hollow rod and ends in the individual adjustment devices 200 .
[0049] Since the main adjustment device 100 and the individual adjustment devices 200 are axially decoupled from each other in a special operating condition of the double seat valve, especially the location of the first closing element 3 must be recorded if needed at every point in time, a position indicator rod 7 a is provided, which each time concentrically penetrates the first actuator stem 103 completely and the second actuator stem 203 up to the first control rod 3 a , which ends in the control device on one end and with its frontal end is screwed into the second actuator stem 203 which is tightly screwed with the first control rod 3 a.
[0050] For the control of the main adjustment device 100 a first pressurizing medium connection 7 b is provided on the control device 7 through which a first pressurizing medium flow D 1 is charged or discharged. Alternatively to this the main adjustment device 100 can be charged using a fourth pressurizing medium connection 210 arranged on the individual adjustment devices 200 with an alternate first pressurizing medium flow D 1 *. To generate the partially open positions T 1 , T 2 the individual adjustment devices 200 have a second and a third pressurizing medium connection 208 , 209 available for a second and third pressurizing medium flow D 2 , D 3 .
[0051] The housing of the main adjustment device 100 ( FIG. 2 ; the multiplicity of seals of the device are here and in further figures not specified individually) consists of a first and a second housing member 101 , 102 , which are essentially made from housing rough parts of the same shape. A first actuating piston 104 with piston seal is arranged on the first actuator stem 103 and fixed there with a non-specified nut. A pretensioned main spring 105 finds its abutment on the one end on the first actuating piston 104 and on the other end on the first housing member 101 . After the installation of the first actuating piston 104 , the first actuator stem 103 and the main spring 105 in both housing members 101 , 102 the latter are preferably integrally joined together, especially by welding. The seals and guide bushings in housing 101 / 102 of the main adjustment device 100 are also exchangeable after their final assembly. The hollow first actuator stem 103 penetrated by the position indicator rod 7 a , and the ring channel 106 formed between these two rods 7 a , 103 serve for the transport of the first pressurizing medium flow D 1 or of the first alternate pressurizing medium flow D 1 *. In each case both reach through the first cross holes 106 a as the first pressurizing medium flow D 1 . 1 (s. FIG. 3 ) in a first pressurizing medium chamber 100 a formed between the first actuator piston 104 and the second housing member 102 , from where they also flow out in the opposite direction.
[0052] Below the main adjustment device 100 the individual adjustment devices 200 are additively inserted. The latter, seen from top to bottom, are made up of a first individual adjustment device 200 . 1 for generation of the first partially open position T 1 of the first closing element 3 and by a second individual adjustment device 200 . 2 for generation of the second partially open position T 2 of the second closing element 4 . The housings of the individual adjustment devices 200 are formed from a third and a fourth housing member 201 , 202 , which are made essentially from housing rough parts of the same shape, and after the assembly of the mounting parts are preferably integrally joined together, especially by welding.
[0053] In the first individual adjustment device 200 . 1 a second actuating piston 205 provided on the circumference with a piston seal is arranged by which a headpiece 203 a , which is molded on the second actuator stem 203 and enlarged in diameter compared to it, engages interlocking and sealing in such a way so that the second actuator stem 203 and the second actuating piston 205 can be seen as connected permanently together. A circlip 214 is used for fixing the headpiece 203 a in the second actuating piston 205 . Between the second actuating piston 205 and the third housing member 201 a second pressurizing medium chamber 200 a is formed, which is connected with the second pressurizing medium connection 208 .
[0054] Below the second actuating piston 205 a third working piston 206 is arranged with a provided piston seal on the circumference in the fourth housing member 202 , which is positioned moveable in the axial direction in the interior on the third actuator stem 204 which is designed as a hollow rod and is able to be brought with this in the direction of the second partially open position T 2 on a shaped recess 204 a on the end of the actuator stem 204 in a clamped connection. A third pressurizing medium chamber 200 b is formed between the third actuating piston 206 and the fourth housing member 202 , which is connected with the third pressurizing medium connection 209 . A fourth pressurizing medium chamber 200 c is circumferentially encompassed by the housing of the individual adjustment device 201 / 202 , on one face side by the second working piston 205 and on the other face side by the third working piston 206 . The fourth pressurizing medium chamber 200 c is fed if necessary either using the ring channel 106 and from this by a second pressurizing medium partial flow D 1 . 2 (see FIG. 3 ) below the second cross hole 203 c branching off from the headpiece 203 a or using the fourth pressurizing medium connection 210 of the alternate first pressurizing medium flow D 1 *. In the illustrated exemplary embodiment the fourth pressurizing medium connection 210 is actually blinded by a sealing plug 211 .
[0055] Between the headpiece 203 a and the third actuator stem 204 a second spring 207 is arranged in the area of the second individual adjustment device 200 . 2 within an expansion of the third actuator stem 204 having a hollow rod shaped design, whose pretensioning is measured so that the second closing member 4 , designed as a seat disc, is pressed in its closing position with sufficient force on the assigned second seat surface 2 b . In the open position of the double seat valve ( FIG. 3 ) the somewhat reduced pretensioning is still sufficient, because of an insignificant elongation of the second spring 207 , to press the closing elements 3 , 4 together with sufficient force so that the leakage chamber 5 is securely sealed from the environment by the seal 10 .
[0056] The end-of-travel limit of the second actuating piston 205 for the first partially open position T 1 ( FIG. 4 ) and that of the third actuating piston 206 for the second partially open position T 2 ( FIG. 5 ) is done by a stop ring 213 axially movable on both sides, which is permanently arranged on housings 201 / 202 between the actuating pistons 205 , 206 . The first partially open position T 1 results unavoidably by the axial distance between the stop ring 213 and the second actuating piston 205 (first partial piston travel a; T 1 =a), if the possible displacement between the headpiece 203 a and the end of the third actuator stem 204 (second partial piston travel b) is measured so that a≦b is given ( FIG. 2 ). Conformance to the condition a≧b guarantees on the other hand, that the closing element 4 is pressed by the headpiece 203 a in the partially open position T 1 statically determined by its assigned second seat surface 2 b , which then supports the headpiece 203 a on recess 204 a and not directly over the second actuating piston 205 on the stop ring 213 .
[0057] The possible travel distance of the third actuating piston 206 to its stop on the stop ring 213 is determined on the exterior by the third partial piston travel c, whereas the third actuating piston 206 can travel in the interior by a fourth partial piston travel d, which is designed inevitably smaller than the third partial piston travel c until it ends in the clamping connection with the recess 204 a . As a result through the actuation of the third actuating piston 206 results in the second partially open position T 2 , which is determined (T 2 =c−d) by the difference [c−d] ( FIG. 2 ).
[0058] The first control rod 3 a is screwed with the second actuator stem 203 in the area of the second individual adjustment device 200 . 2 ( FIG. 2 ). In order to prevent or at least to complicate a loosening of this screw connection, it is counter secured by the position indicator rod 7 a . For this presses the latter, which for its part is coaxially screwed in the second actuator stem 203 , with a second end surface 7 c on a first end surface 3 b of the first control rod 3 a . Through this the position indicator rod 7 a forms the immediate continuation of the first control rod 3 a , so that by this arrangement the respective position of the first closing element 3 is securely acquired.
[0059] In the frontal end of the first actuator stem 103 reaching into the individual adjustment devices 200 a header 103 a is screwed in, which engages into a cutout 203 b within the headpiece 203 a , whose diameter is enlarged compared to it and which is formed onto the second actuator stem 203 . The header 103 a is arranged in the cutout 203 b movable both in the axial as well as the rotational direction, whereby the axial movement is limited by a stop face 203 d , which forms the frontal end circumferential border of the recess 203 b . To reduce the friction a plain bearing bush 212 is provided between the header 103 a and the recess 203 b . Through the pertinent embodiment in the area of the header 103 a , the main adjustment device 100 and the individual adjustment devices 200 are axially and in the general direction of rotation decoupled from each other in the direction of the first partially open position T 1 .
[0060] The double seat valve is transported into its full open position H ( FIG. 3 ) if the first pressurizing medium flow D 1 of the proposed device is fed through the ring channel 106 . The first pressurizing medium flow D 1 branches out at the first cross hole 106 a into the first pressurizing medium partial flow D 1 . 1 , which arrives in the first pressurizing medium chamber 100 a of the main adjustment device 100 , and into the second pressurizing medium partial flow D 1 . 2 , which almost at the same time loads the fourth pressurizing medium chamber 200 c of the first individual adjustment device 200 . 1 through the second cross hole 203 c . Alternatively to the preceding described loading of the pressurizing medium chambers 100 a and 200 c with pressurizing medium, their loading can also be done through the fourth pressurizing medium connection 210 . In this case the alternate first pressurizing medium flow D 1 * first enters into the fourth pressurizing medium chamber 200 c completely, in order to then divert the first pressurizing medium partial flow D 1 . 1 from this through the second cross hole 203 c , the ring channel 106 and the first cross holes 106 a into the first pressurizing medium chamber 100 a.
[0061] The two actuating pistons 104 and 205 loaded with pressurizing medium in this manner take hold directly or indirectly (through header 103 a ) with their respective opening force, which results from the respective pressure in the assigned pressurizing medium chamber 100 a , 200 c and each provided effective piston surface, on the first actuator stem 103 and therefore together override the pretensioned force of the main spring 105 . Through the axial decoupling of the arrangement in the area of the header 103 a/ headpiece 203 a combination the grabbing pressure and/or friction forces against the opening movement on the two closing elements 3 , 4 can be overridden if necessary by only two second actuating pistons 205 . Seen as a whole both actuating pistons 104 , 205 in the process of the opening movement override the total resisting force which results from the pretensioning force of the main spring 105 and from the total pressure and/or friction forces, so that the first individual adjustment device 200 . 1 in this movement phase receives the task of a so-called batch actuator, whereby the preceding described diameter reduction of the main adjustment device 100 is justified and achievable.
[0062] The seat cleaning of the first closing element 3 ( FIG. 4 ) is done by the introduction of the second pressurizing medium flow D 2 in the second pressurizing medium chamber 200 a of the first individual adjustment device 200 . 1 on the route over the second pressurizing medium connection 208 . Thus the second actuating piston 205 which is loaded with pressurizing medium is pushed down in the partially open position T 1 =a (cf. also FIG. 2 ), whereby the assigned first seat surface 2 a is exposed and the first seat cleaning stream R 1 from the first valve housing member 1 a reaches on the way over the gapwise opened seat 2 a / 8 into the leakage chamber 5 . Since the first actuator stem 103 is end-of-travel limited in the direction of the individual adjustment devices 200 , the header 103 a also remains in its appropriate end position. Through the axial decoupling between the header 103 a and headpiece 203 a the second actuating piston 205 can axially slide itself onto the header 103 a , so that the stop face 203 d loosens itself from the later and distances so far until the actuating piston 205 takes its bearing on the exterior of the stop ring 213 . In order to ensure a stop of the actuating piston 205 on the stop ring 213 and not over the headpiece 203 a on frontal end of the third actuator stem 204 , to the recess 204 a , the condition a≦b must be met.
[0063] The seat cleaning of the second closing element 4 ( FIG. 5 ) is achieved in that the third pressurizing medium flow D 3 is introduced by the third pressurizing medium connection 209 into the third pressurizing medium chamber 200 b of the second individual adjustment device 200 . 2 . Thus the third actuating piston 206 which is loaded by pressurizing medium moves in the direction toward the stop ring 213 . On its travel distance up to resting on this it must overcome the third partial piston travel c (cf. FIG. 2 ). Beforehand it gets in a clamping connection after the fourth partial piston travel d with its clamping flat 206 a on recess 204 a , so that after a stop on the stop ring 213 from the third actuator stem 204 and thus the required partially open position T 2 =c−d is completed from the second closing element 4 against the pretension force of the second spring 207 . The latter finds an abutment on the headpiece 203 a , which supports itself unmoveablely with its stop face 203 d on the header 103 a , since the latter is securely fastened by the first actuator stem 103 in connection with the first actuating piston 104 from the pretensioning force of the main spring 105 in this end position. Through the second partially open position T 2 the second closing element 4 is removed gapwise from its assigned second seat surface 2 b , so that the second seat cleaning stream R 2 from the second valve housing member 1 b reaches over the gap between the exposed second seat surface 2 b and the second seat seal 9 into the leakage chamber 5 .
[0064] In the second individual adjustment device 200 . 2 inside the individual adjustment devices 200 ( FIG. 6 ), in which the third actuating piston 206 with a so-called “batch function” is provided, the latter is connected tightly, however able to be loosened, on its side facing the second actuating piston 205 with a smaller diameter additional piston 206 . 1 . The additional piston 206 . 1 working together with a housing ring 213 . 1 fixed on the housing 201 / 202 of the individual adjustment device 200 forms a fifth pressurizing medium chamber 200 d , which is connected with a third pressurizing medium chamber 200 b formed between the third actuating piston 206 and a non-specified bottom member of the fourth housing member 202 . At the same time the additional piston 206 . 1 has a larger diameter exterior piston section 206 . 1 a and a smaller diameter interior piston section 206 . 1 b, whereby the exterior piston section 206 . 1 a features an external diameter D a and the interior piston section 206 . 1 b an internal diameter D i ( FIG. 6 a ). The interior piston section 206 . 1 b is sealed on its frontal end by means of seals 217 which are coaxially arranged with each other against the third actuating piston 206 and screwed with this using a number of bolted connections 206 . 2 arranged distributed over its circumference. The exterior piston section 206 . 1 a is circumferentially sealed against the shell of a cylindrical recess 213 . 1 a in the housing ring 213 . 1 by means of a first piston seal 215 . In the same manner the interior piston section 206 . 1 b is sealed circumferentially in a coaxial through bore 213 . 1 b in the housing ring 213 . 1 by means of a second piston seal 216 . The third pressurizing medium flow D 3 is introduced over the third pressurizing medium connection 209 first to the third pressurizing medium chamber 200 b . From there the pressurizing medium reaches over a first pressurizing medium channel 206 b running between the two seals 217 in an axial direction through the third actuating piston 206 , in order to finally reach into a second pressurizing medium channel 206 . 1 d which is running corresponding with these in the additional piston 206 . 1 up to the fifth pressurizing medium chamber 200 d.
[0065] The housing ring 213 . 1 has a circumferential radial projection 213 . 1 c , with which it is positively fastened in the connection area between the third and the fourth housing member 201 , 202 . Between the housing ring 213 . 1 and the third actuating piston 206 a preceding fourth pressurizing medium chamber 200 c * is designed, in which the fourth pressurizing medium connection 210 discharges. Through the latter the alternate first pressurizing medium flow D 1 * is charged or discharged for implementation of the full opening stroke H for the independently actuated closing element 3 . The preceding fourth pressurizing medium chamber 200 c * is connected through at least one connection channel 213 . 1 d with the designed fourth pressurizing medium chamber 200 c which is between the second actuating piston 205 on one side and the housing ring 213 . 1 in connection with the additional piston 206 . 1 on the other side, which is located in a part of the housing ring 213 . 1 containing the cylindrical recess 213 . 1 a on the exterior.
[0066] The radial projection 213 . 1 c is designed on its side facing the third actuating piston 206 in a manner so that the latter, after implementation of the second partial piston travel c ( FIG. 6 a ), there meets an end-of-travel limit and thus the corresponding limit of the second partially open position T 2 within the second individual adjustment device 200 . 2 is guaranteed.
[0067] A corresponding limit of the first partial piston travel a under the condition a≦b (cf. also FIG. 2 ) is done by the first individual adjustment device 200 . 1 , which is put into effect by the first partially open position T 1 in that the second actuating piston 205 comes to rest on the housing ring 213 . 1 which is permanently located on the housing 201 / 202 . Under the condition a≧b after implementation of the first partially open position T 1 a modified headpiece 203 a * of the second actuator stem 203 (not specified) activated by the first closing element 3 comes to rest on recess 204 a (also not specified), as was already described in connection with the first embodiment of the individual adjustment devices 200 according to the FIGS. 1 to 5 , especially according to FIG. 4 .
[0068] The third actuating piston 206 strikes over the clamping flat 206 a on the recess 204 a (cf. also FIG. 5 ), to produce the completion of the second partially open position T 2 of the second closing element 4 in one or the other directions. The axial extension of the end of the modified headpiece 203 a * facing the third actuating piston 206 makes it necessary to provide the additional piston 206 . 1 with a coaxial piston bore 206 . 1 c , which surrounds the modified headpiece 203 a * with clearance outside.
REFERENCE NUMBERS OF THE ABBREVIATIONS USED
[0000]
1 valve housing
1 a first valve housing member
1 b second valve housing member
2 seat ring
2 a first seat surface
2 b second seat surface
2 c connection orifice
3 first closing element
3 a first control rod
3 b first end surface
4 second closing element
4 a second control rod
5 leakage chamber
6 lantern housing
7 control device
7 a position indicator rod
7 b first pressurizing medium connection
7 c second end surface
8 first seat seal (radial)
9 second seat seal (radial, axial)
10 seal (axial)
11 cleaning solution connection
100 main adjustment device
100 a first pressurizing medium chamber
101 / 102 main adjustment device housing
101 first housing member
102 second housing member
103 first actuator stem
103 a header
104 first actuating piston
105 main spring
106 ring channel
106 a first cross hole
200 individual adjustment device
200 . 1 first individual adjustment device
200 . 2 second individual adjustment device
200 a second pressurizing medium chamber
200 b third pressurizing medium chamber
200 c fourth pressurizing medium chamber
200 c * preceding fourth pressurizing medium chamber
200 d fifth pressurizing medium chamber
201 / 202 individual adjustment device housing
201 third housing member
202 fourth housing member
203 second actuator stem
203 a headpiece
203 a * modified headpiece
203 b cutout
203 c second cross hole
203 d stop face
204 third actuator stem
204 a recess
205 second actuating piston
206 third actuating piston
206 a clamping flat
206 b first pressurizing medium channel
206 . 1 additional piston
206 . 1 a exterior piston section
206 . 1 b interior piston section
206 . 1 c coaxial piston bore
206 . 1 d second pressurizing medium channel
206 . 2 bolted connection
207 second spring
208 second pressurizing medium connection
209 third pressurizing medium connection
210 fourth pressurizing medium connection
211 sealing plug
212 plain bearing bush
213 stop ring
213 . 1 housing ring
213 . 1 a cylindrical cutout
213 . 1 b coaxial through-bore
213 . 1 c radial projection
213 . 1 d connection channel
214 circlip
215 first piston seal
216 second piston seal
217 seal
a first partial piston travel
b second partial piston travel
c third partial piston travel
d fourth partial piston travel
D 1 first pressurizing medium flow
D 1 . 1 first pressurizing medium partial flow
D 1 . 2 second pressurizing medium partial flow
D 1 * alternate first pressurizing medium flow
D 2 second pressurizing medium flow
D 3 third pressurizing medium flow
D a outer diameter
D i inner diameter
H full opening stroke (fully open position)
R cleaning solution
R 1 first seat cleaning stream
R 2 second seat cleaning stream
T 1 first partially open position (T 1 =a)
T 2 second partially open position (T 2 =c−d)
|
The invention relates to a device for actuating double seat valves, which are especially suitable for the food and beverage industry and which have an independently actuated first closing element ( 3 ), which is designed as a sliding piston and a fully dependent on this actuated second closing element ( 4 ), which is designed as a seat disc, whereby the actuator ( 100, 200 ) produces at all times using a main adjustment device ( 100 ) for the fully open position (H) as well as, for the case of maximum requirements, the respective individual adjustment devices ( 200; 200.1, 200.2 ) which are assigned to the closing elements ( 3, 4 ) for generation of the partially open positions (T 1, T 2 ) acting in opposite directions for the seat cleaning of the closing elements ( 3, 4 ). The object of the invention is to design a device according to this generic type in such a manner that it is constructed as simply as possible and is easily and economically adjustable to the various requirements which are put onto a double seat valve of the type in discussion (only full opening stroke or full opening stroke as well as seat cleaning partial strokes). This is thus achieved in that the individual adjustment devices ( 200; 200.1, 200.2 ) are designed stand-alone and are additively inserted between the main adjustment device ( 100 ) and a valve housing ( 1 ), that the third working piston ( 206;206/206.1 ) is positioned able to be moved axially on the second control rod ( 4 a, 204 ) which is designed as a hollow rod, and encloses the first control rod ( 3 a, 203 ) and is able to be brought in the direction of the second partially open position (T 2 ) in a clamped connection, that the second actuating piston ( 205 ) is tightly connected on one side with the first control rod ( 3 a, 203 ) which adjusts the first closing element ( 3 ), that it is otherwise directly or indirectly positioned able to be moved axially on a first actuator stem ( 103 ) of the main adjustment device ( 100 ) and is able to be brought with this in the direction of the fully open position (H) in a clamping connection, and that it is able to be loaded with pressurizing medium on each of its two piston surfaces (FIG. 2 ).
| 8
|
[0001] This application is a continuation of U.S. application Ser. No. 10/908,738, filed May 24, 2005, which is a divisional of U.S. application Ser. No. 09/816,839, filed Mar. 23, 2001, now U.S. Pat. No. 6,998,468, which claims priority to U.S. Provisional Application No. 60/191,429, filed Mar. 23, 2000, the disclosure of each of which is incorporated herein by its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to inhibitor molecules specific to complement C2 and its activation fragment C2a, the use of such inhibitor molecules to block complement activation via the classical pathway and the lectin pathway, treatment of diseases associated with excessive complement activation, and the diagnostic determination of the amount of C2a present in a biological sample.
BACKGROUND OF THE INVENTION
[0003] The complement system is part of the innate immune system and consists of many components that act in a cascade fashion. This system plays a central role in both the clearance of immune complexes and the immune response to infectious agents, foreign antigens, virus-infected cells and tumor cells. However, complement is also involved in pathological inflammation and in autoimmune diseases. Therefore, inhibition of excessive or uncontrolled activation of the complement cascade could provide clinical benefit to patients with such diseases and conditions.
[0004] The complement system can be activated in three ways, either by one of the two primary activation pathways, designated the classical and the alternative pathways (V. M. Holers, In Clinical Immunology: Principles and Practice , ed. R. R. Rich, Mosby Press, 1996, 363-391), or by a third pathway, the lectin pathway activated by mannan-binding lectin (MBL) (M. Matsushita, Microbiol. Immunol., 1996, 40: 887-893; M. Matsushita et al., Immunobiol., 1998, 199: 340-347; T. Vorup-Jensen et al., Immunobiol., 1998, 199: 348-357).
[0005] The classical pathway is a calcium/magnesium-dependent cascade, which is normally activated by the formation of antigen-antibody complexes. C1, the first enzyme complex in the cascade, is a pentamolecular complex consisting of C1q, 2 C1r molecules, and 2 C1 s molecules. This complex binds to an antigen-antibody complex through the C1q domain to initiate the cascade. Once activated, C1s cleaves C4 resulting in C4b, which in turn binds C2. C2 is cleaved by C1s, resulting in the activated form, C2a, bound to C4b and forming the classical pathway C3 convertase.
[0006] The alternative pathway is a magnesium-dependent cascade and is antibody-independent. This pathway is activated by a variety of diverse substances including, e.g., cell wall polysaccharides of yeast and bacteria, and certain biopolymer materials. When the C3 protein binds on certain susceptible surfaces, it is cleaved to yield C3b thus initiating an amplification loop.
[0007] The lectin pathway involves complement activation by MBL through two serum serine proteases designated MASP-1 and MASP-2 (as opposed to C1r and C1s in the classical complement pathway). Like the classical complement pathway, the lectin complement pathway also requires C4 and C2 for activation of C3 and other terminal components further downstream in the cascade (C. Suankratay et al., J. Immunol., 1998, 160: 3006-3013; Y. Zhang et al., Immunopharmacol., 1999, 42: 81-90; Y. Zhang et al., Immunol., 1999, 97: 686-692; C. Suankratay et al., Clin. Exp. Immunol., 1999, 117: 442-448). Alternative pathway amplification is also required for lectin pathway hemolysis in human serum (C. Suankratay et al., J. Immunol., 1998, 160: 3006-3013; C. Suankratay et al., Clin. Exp. Immunol., 1998, 113: 353-359). In short, Ca ++ -dependent binding of MBL to a mannan-coated surface triggers activation of C3 following C4 and C2 activation, and the downstream activation of C3 and the terminal complement components then require the alternative complement pathway for amplification.
[0008] Activation of the complement pathway generates biologically active fragments of complement proteins, e.g. C3a, C4a and C5a anaphylatoxins and sC5b-9 membrane attack complex (MAC), which mediate inflammatory activities involving leukocyte chemotaxis, activation of macrophages, neutrophils, platelets, mast cells and endothelial cells, vascular permeability, cytolysis, and tissue injury
[0009] (R. Schindler et at., Blood, 1990, 76: 1631-1638; T. Wiedmer, Blood, 1991, 78: 2880-2886; M. P. Fletcher et al., Am. J, Physiol., 1993, 265: 111750-1761).
[0010] C2 is a single-chain plasma protein of molecular weight of 102 kD, which is specific for the classical and the lectin complement pathways. Membrane bound C4b expresses a binding site which, in the presence of Mg ++ , binds the proenzyme C2 near its amino terminus and presents it for cleavage by C1s (for the classical complement pathway) or MASP-2 (for the lectin complement pathway) to yield a 30 kD amino-terminal fragment, C2b, and a 70 kD carboxy-terminal fragment, C2a (S, Nagasawa et al., Proc. Natl. Acad. Sci. ( USA ), 1977, 74: 2998-3003). The C2b fragment may be released or remain loosely attached to C4b. The C2a fragment remains attached to C4b to form the C4b2a complex, the catalytic components of the C3 and C5 convertases of the classical and the lectin complement pathways. The enzymatic activity in this complex resides entirely in C2a, C4b acting to tether C2a to the activating surface.
[0011] Monoclonal antibodies (MAbs) to human C2 and its fragments C2a and C2b were made by immunizing mice with purified human C2 (E. I. Stenbaek et al., Mol. Immunol., 1986, 23: 879-886; T. J. Oglesby et al., J. Immunol., 1988, 141: 926-932). The novel anti-C2a MAbs of the present invention were made by immunizing mice with purified human C2a fragment and were shown to have inhibitory activity against the classical pathway complement activation (see below). These anti-C2a MAbs are distinct from the known anti-C2b MAb (see T. J. Oglesby et al., J. Immunol., 1988, 141: 926-932) because they bind to different segments of C2 and inhibit the classical complement pathway by interfering the interaction between C2 and C4 (T. J. Oglesby et al., J. Immunol., 1988, 141: 926-932). By virtue of this inhibition, the anti-C2a MAbs of the present invention are the first Mab demonstrated to be effective in inhibiting the classical complement pathway.
[0012] Targeting C2a and/or the C2a portion of C2 for complete inhibition of the classical and the lectin complement pathways has several advantages including, for example: (1) C2 and C2a are specific for the classical and the lectin complement pathways, and thus inhibition of C2 and/or C2a would achieve complete and selective inhibition of these two complement pathways without affecting the alternative complement pathway; (2) the concentration of C2 in human blood is one of the lowest (ca. 20 μg/ml) among other soluble complement components, therefore inhibitors of C2 or C2a would have a unique dose advantage; and (3) since C2a is the catalytic subunit of the C3 and C5 convertases, inhibition of C2 or the C2a portion of C2 would block the activation of C3 and C5.
[0013] The down-regulation of complement activation has been demonstrated to be effective in treating several disease indications in animal models and in ex vivo studies, e.g., systemic lupus erythematosus and glomerulonephritis (Y. Wang et al., Proc. Natl. Acad. Sci . ( USA ), 1996, 93: 8563-8568), rheumatoid arthritis (Y. Wang et al., Proc. Natl. Acad. Sci . ( USA ), 1995, 92: 8955-8959), in preventing inflammation associated with cardiopulmonary bypass and hemodialysis (C. S. Rinder et al., J. Clin. Invest., 1995, 96: 1564-1572; J. C. K. Fitch et al., Circulation, 1999, 100: 2499-2506; H. L. Lazar et al., Circulation, 1999, 100: 1438-1442), hyperacute rejection in organ transplantation (T. J. Kroshus et al., Transplantation, 1995, 60: 1194-1202), myocardial infarction (J. W. Homeister et al., J. Immunol., 1993, 150: 1055-1064; H. F. Weisman et al., Science, 1990, 249: 146-151), reperfusion injury (E. A. Amsterdam et al., Am. J. Physiol., 1995, 268: H448-H457), and adult respiratory distress syndrome (R. Rabinovici et al., J. Immunol., 1992, 149: 1744-1750). In addition, other inflammatory conditions and autoimmune/immune complex diseases are also closely associated with complement activation (V. M. Holers, ibid., B. P. Morgan. Eur. J. Clin. Invest., 1994, 24: 219-228), including thermal injury, severe asthma, anaphylactic shock, bowel inflammation, urticaria, angioedema, vasculitis, multiple sclerosis, psoriasis, dermatomyositis, myasthenia gravis, membranoproliferative glomerulonephritis, and Sjögren's syndrome.
SUMMARY OF THE INVENTION
[0014] The present invention includes inhibitor molecules having a binding region specific for C2a or the C2a portion of C2. The inhibitor molecule may be an antibody or a homologue, analogue or fragment thereof, a peptide, an oligonucleotide, a peptidomimetic or an organic compound. Antibody fragments can be Fab, F(ab′) 2 , Fv or single chain Fv. The inhibitor molecule may be in the form of a pharmaceutical composition.
[0015] One embodiment of the present invention includes an inhibitor molecule comprising a monoclonal antibody. The antibody may be chimeric, deimmunized, humanized or human antibody. Specifically, the monoclonal antibody may be the monoclonal antibody designated 175-62.
[0016] Another embodiment of the invention is a hybridoma producing the monoclonal antibody 175-62.
[0017] Another embodiment of the invention includes monoclonal antibodies or a fragment, analogue or homologue thereof, or a peptide, oligonucleotide, peptidomimetic or an organic compound which bind to the same epitope as the antibody 175-62. These antibodies can include Fab, F(ab′) 2 . Fv or single chain Fv, and may be chimeric, deimmunized, humanized or human antibody. In addition, the present invention includes cell lines that produces the monoclonal antibody or fragment thereof that bind to the same epitope as the antibody 175-62.
[0018] The present invention also includes molecules that inhibit complement activation by inhibiting both the classical and lectin complement pathways. The preferred molecules of the present invention inhibit complement activation at a molar ratio of inhibitor molecule to C2 at 1:2.
[0019] Another embodiment of the present invention includes a method of treating a disease or condition that is mediated by excessive or uncontrolled activation of the complement system by administering, in vivo or ex vivo, an inhibitor molecule that specifically binds C2a or the C2a portion of C2.
[0020] One example of a Mab, designated 175-62, that binds to C2a and blocks its ability to activate complement was generated as described below. The hybridoma producing this antibody was deposited at the American Type Culture Collection, 10801 University Blvd., Manassas, Va. 20110-2209, under Accession Number PTA-1553, on Mar. 22, 2000.
BRIEF DESCRIPTION OF THE FIGURES
[0021] FIG. 1 shows the binding of anti-C2a MAbs (175 series), anti-C5 Mab (137-76), and anti-factor D Mab (166-32) to purified human C2a in an ELISA. The Y-axis represents the reactivity of the MAbs with C2a expressed as optical density (OD) at 450 nm and the X-axis represents the concentration of the MAbs. MAb 175-62 shows the strongest reactivity with C2a.
[0022] FIG. 2 shows the inhibition of classical pathway hemolysis of sensitized chicken red blood cells (RBCs) by anti-C2a MAbs in the presence of 3% human serum. The controls were anti-factor D Mab (166-32) and the anti-C5 MAb (137-76). Anti-factor D Mab 166-32 specifically inhibits the alternative complement pathway, therefore it does not inhibit the classical pathway hemolysis. The Y-axis represents the % hemolysis inhibition, as further described in the text. The X-axis represents the concentration of the MAbs. All anti-C2a MAbs strongly inhibit classical pathway hemolysis.
[0023] FIG. 3 shows that anti-C2a MAb 175-62 inhibits classical pathway (CP) hemolysis at a molar ratio of 1:2 (MAb 175-62 to C2). The filled circles represent MAb 175-62. The open squares represent hemolysis in the absence of MAb 175-62. The Y-axis represents the % hemolysis inhibition. The X-axis represents the concentration of serum. The classical pathway hemolytic activity of C2 (0.2 μM) in normal human serum is completely inhibited when the serum was pre-treated with 0.1 μM of MAb 175-62.
[0024] FIG. 4 shows an assay for testing the inhibition of alternative pathway (AP) hemolysis of unsensitized rabbit RBCs by anti-C2a, anti-factor D and anti-C5 MAbs, in the presence of 10% human serum. The Y-axis represents the % hemolysis inhibition, as further described in the text. The X-axis represents the concentration of the MAbs. The data illustrate that none of the anti-C2a MAbs inhibit the alternative complement pathway.
DETAILED DESCRIPTION
[0025] The inhibitor molecules of the present invention include monoclonal antibodies as well as homologues, analogues and modified or derived forms thereof, including immunoglobulin fragments such as Fab, F(ab′) 2 , and Fv, and single chain antibodies. Also included are small molecules including peptides, oligonucleotides, peptidomimetics and organic compounds.
[0026] One embodiment of the invention includes anti-C2a MAbs, which can be raised by immunizing rodents (e.g. mice, rats, hamsters and guinea pigs) with either (1) native C2a derived from enzymatic digestion of C2 purified from human plasma or serum, or (2) recombinant C2a or its fragments expressed by either eukaryotic or prokaryotic systems. Other animals can be used for immunization, e.g. non-human primates, transgenic mice expressing human immunoglobulins, and severe combined immunodeficient (SCID) mice transplanted with human B-lymphocytes.
[0027] Hybridomas can be generated by conventional procedures by fusing B-lymphocytes from the immunized animals with myeloma cells (e.g., Sp2/0 and NS0), as described by G. Köhler and C. Milstein ( Nature, 1975, 256: 495-497). In addition, anti-C2a antibodies can be generated by screening recombinant single-chain Fv or Fab libraries from human B-lymphocytes in a phage-display system. The specificity of the MAbs to human C2a can be tested by enzyme linked immunosorbent assay (ELISA), Western immunoblotting, or other immunochemical techniques.
[0028] The inhibitory activity on complement activation of antibodies identified in the screening process can be assessed by hemolytic assays using either unsensitized rabbit or guinea pig RBCs for the alternative complement pathway, or sensitized chicken or sheep RBCs for the classical complement pathway. Those hybridomas that exhibit an inhibitory activity specific for the classical complement pathway are cloned by limiting dilution. The antibodies are purified for characterization for specificity to human C2a by the assays described above.
[0029] When treating inflammatory or autoimmune diseases in humans, the anti-C2a antibodies may be chimeric, deimmunized, humanized or human antibodies. Such antibodies can reduce immunogenicity, thereby avoiding a human/anti-mouse antibody (HAMA) response. It is preferable that the antibody be IgG4, IgG2, or other genetically mutated IgG or IgM which does not augment antibody-dependent cellular cytotoxicity (S. M. Canfield et al., J. Exp. Med., 1991, 173: 1483-1491) and complement mediated cytolysis (Y. Xu et al., J. Biol. Chem., 1994, 269: 3468-3474; V. L. Pulito et al., J. Immunol., 1996, 156: 2840-2850).
[0030] Chimeric antibodies are produced by recombinant processes well known in the art, and have an animal variable region and a human constant region. Humanized antibodies have a greater degree of human peptide sequences than do chimeric antibodies. In a humanized antibody, only the complementarity determining regions (CDRs), which are responsible for antigen binding and specificity, are animal derived. The amino acid sequence corresponding to the animal antibody, and substantially all of the remaining portions of the molecule (except, in some cases, small portions of the framework regions within the variable region) are human derived and correspond in amino acid sequence to a human antibody. See, e.g., L. Riechmann et al., Nature, 1988, 332: 323-327; G. Winter, U.S. Pat. No. 5,225,539; C. Queen et al., U.S. Pat. No. 5,530,101.
[0031] Deimmunized antibodies are antibodies in which the T-helper epitopes have been eliminated, as described in International Patent Application PCT/GB98/01473. They have either reduced or no immunogenicity when administered in vivo.
[0032] Human antibodies can be made by several different methods, including the use of human immunoglobulin expression libraries (Stratagene Corp., La Jolla, Calif.) to produce fragments of human antibodies (VH, VL, Fv, Fd, Fab, or F(ab′) 2 ) to construct whole human antibodies using techniques similar to those for producing chimeric antibodies. Human antibodies can also be produced in transgenic mice with a human immunoglobulin genome. Such mice are available from Abgenix, Inc., Fremont, Calif., and Medarex, Inc., Annandale, N.J.
[0033] One can also create single peptide chain binding molecules in which the heavy and light chain Fv regions are connected. Single chain antibodies (“scFv”) and the method of their construction are described in U.S. Pat. No. 4,946,778. Alternatively, Fab can be constructed and expressed by similar means (M. J. Evans et al., J. Immunol. Meth., 1995, 184: 123-138).
[0034] Antibodies, fragments thereof, and single chain antibodies that are wholly or partially derived from human are less immunogenic than wholly murine MAbs, and therefore, less likely to evoke an immune or allergic response. Consequently, human-derived antibodies are better suited for in vivo administration in humans than wholly animal antibodies, especially when repeated or long-term administration is necessary. In addition, smaller size antibody fragments may help improve tissue bioavailability, which may offer better dose accumulation in certain disease indications.
[0035] Based on the molecular structures of the variable regions of the anti-C2a antibodies, one can use molecular modeling and rational molecular design to generate and screen small molecules that mimic the molecular structures of the binding region of the antibodies and inhibit the activities of C2a. These small molecules can be peptides, peptidomimetics, oligonucleotides, or organic compounds. The mimicking molecules can be used as inhibitors of complement activation in inflammatory indications and autoimmune diseases. Alternatively, one can use large-scale screening procedures commonly used in the field to isolate suitable small molecules from libraries of combinatorial compounds.
[0036] Applications of the Anti-C2a Molecules
[0037] The anti-C2a binding molecules, antibodies, and fragments of the present invention can be administered to patients in an appropriate pharmaceutical formulation by a variety of routes, including, but not limited, intravenous infusion, intravenous bolus injection, and intraperitoneal, intradermal, intramuscular, subcutaneous, intranasal, intratracheal, intraspinal, intracranial, and oral routes. Such administration enables them to bind to endogenous C2a or C2 and thus inhibit the generation of C3b, C3a and C5a anaphylatoxins, and C5b-9.
[0038] The estimated dosage of such antibodies and molecules is between 10 and 500 μg/ml of serum. The actual dosage can be determined in clinical trials following the conventional methodology for determining optimal dosages, i.e., administering various dosages and determining which is most effective.
[0039] The anti-C2a inhibitor molecules can function to inhibit in vivo complement activation and inflammatory manifestations that accompany it, such as recruitment and activation of macrophages, neutrophils, platelets, mast cells and endothelial cells, edema, and tissue damage. These inhibitor molecules can be used for treatment of diseases or conditions that are mediated by excessive or uncontrolled activation of the complement system. These include, but are not limited to: (1) tissue damage due to ischemia-reperfusion following acute myocardial infarction, aneurysm, stroke, hemorrhagic shock, crush injury, multiple organ failure, hypovolemic shock and intestinal ischemia; (2) inflammatory disorders, such as, burns, endotoxemia and septic shock, adult respiratory distress syndrome, cardiopulmonary bypass, hemodialysis, anaphylactic shock, severe asthma, angioedema, Crohn's disease, psoriasis, dermomyositis, sickle cell anemia, poststreptococcal glomerulonephritis, and pancreatitis; (3) transplant rejections, such as, hyperacute xenograft rejection; and (4) adverse drug reactions, such as, drug allergy, IL-2 induced vascular leakage syndrome, and radiographic contrast media allergy. Autoimmune disorders including, but not limited to, systemic lupus erythematosus, myasthenia gravis, rheumatoid arthritis, Alzheimer's disease and multiple sclerosis, may also be treated with the inhibitor molecules of the invention.
[0040] The anti-C2a inhibitor molecules can also be used diagnostically to ascertain the presence of, or to measure, C2a in a tissue specimen or a body fluid sample, such as serum, plasma, urine or spinal fluid. In this application, common assay formats can be used, such as immunohistochemistry or ELISA, respectively. Such diagnostic tests could be useful in determining whether certain individuals are either deficient in or overproduce C2a.
[0041] Animal Models of the Therapeutic Efficacy of C2a Inhibitors
[0042] The therapeutic activity of C2a inhibitor molecules in various disease indications described above can be confirmed by using available animal models for various inflammatory and autoimmune manifestations.
[0043] Animal models relevant to various complement-related clinical diseases in humans can be used to confirm the in vivo efficacy of C2a inhibitors. These include, but are not limited to: myocardial ischemia/reperfusion injury (H. F. Weisman et al., Science, 1990, 249: 146-151); myocardial infarction (J. W. Homeister et al., J. Immunol., 1993, 150: 1055-1064), systemic lupus erythematosus and glomerulonephritis (S. K. Datta. Meth. Enzymol., 1988, 162: 385-442; D. J. Salvant et al., Meth. Enzymol., 1988, 162: 421-461), rheumatoid arthritis (Y. Wang et al., Proc. Natl. Acad. Sci . ( USA ), 1995, 92: 8955-8959), adult respiratory distress syndrome (R. Rabinovici et al., J. Immunol., 1992, 149: 1744-1750), hyperacute rejection in organ transplantation (T. J. Kroshus et al., Transplantation, 1995, 60: 1194-1202), burn injury (M. S. Mulligan et al., J. Immunol., 1992, 148: 1479-1485), cardiopulmonary bypass (C. S. Rinder et al., J. Clin. Invest., 1995, 96: 1564-1572).
Example 1
Generation of Anti-C2a MAb Hybridomas
[0044] Eight to twelve-week old male A/J mice (Harlan, Houston. TX) were subcutaneously injected with 20 μg of C2a in complete Freund's adjuvant (Difco Laboratories, Detroit, Mich.) in 200 μl of phosphate-buffered saline (PBS) pH 7.4. The C2a was generated by enzymatic digestion using C1s (Advanced Research Technologies, San Diego, Calif.) conjugated to CNBr-activated Sepharose® 6 MB (Pharmacia Biotech, Piscataway, N.J.), similar to the procedure described in T. J. Oglesby, J. Immunol., 1988, 141: 926-931. The resulting C2a was then purified by passage through a Sephadex®-200 size-exclusion HPLC column. The C2a preparation was tested to be >95% pure by sodium dodecylsulphate (SDS)-polyacrylamide gel electrophoresis (PAGE). C2 was purified from human serum (Advanced Research Technologies).
[0045] At two-week intervals, mice were twice injected subcutaneously with 20 μg of C2a in incomplete Freund's adjuvant. Then, two weeks later, three days prior to sacrifice, the mice were again injected intraperitoneally with 20 μg of the same antigen in PBS.
[0046] For each hybridoma, single cell suspensions were prepared from the spleen of an immunized mouse and fused with Sp2/0 myeloma cells. 5×10 8 of the Sp2/0 and 5×10 8 spleen cells were fused in a medium containing 50% polyethylene glycol (M. W. 1450) (Kodak, Rochester, N.Y.) and 5% dimethylsulfoxide (Sigma Chemical Co., St. Louis, Mo.). The cells were then adjusted to a concentration of 1.5×10 5 spleen cells per 200 μl of the suspension in Iscove medium (Gibco, Grand Island, N.Y.), supplemented with 10% fetal bovine serum, 100 units/ml of penicillin, 100 μg/ml of streptomycin, 0.1 mM hypoxanthine, 0.4 μM aminopterin, and 16 μM thymidine. Two hundred μl of the cell suspension were added to each well of about fifty 96-well microculture plates. After about ten days, culture supernatants were withdrawn for screening for reactivity with purified C2a in ELISA.
[0047] Wells of Immulon® 2 (Dynatech Laboratories, Chantilly, Va.) microtest plates were coated by adding 50 μl of purified human C2a at 50 ng/ml overnight at room temperature. The low concentration of C2a used for coating enabled the selection of high-affinity antibodies. After the coating solution was removed by flicking the plate, 200 μl of BLOTTO (non-fat dry milk) in PBS was added to each well for one hour to block the non-specific sites. An hour later, the wells were then washed with a buffer PBST (PBS containing 0.05% Tween® 20). Fifty microliters of culture supernatants from each fusion well were collected and mixed with 50 μl of BLOTTO and then added to the individual wells of the microtest plates. After one hour of incubation, the wells were washed with PBST. The bound murine antibodies were then detected by reaction with horseradish peroxidase (HRP)-conjugated goat anti-mouse IgG (Fc specific) (Jackson ImmunoResearch Laboratories, West Grove, Pa.) and diluted at 1:2,000 in BLOTTO. Peroxidase substrate solution containing 0.1% 3,3,5,5 tetramethyl benzidine (Sigma) and 0.0003% hydrogen peroxide (Sigma) was added to the wells for color development for 30 minutes. The reaction was terminated by addition of 50 μl of 2M H 2 SO 4 per well. The OD at 450 nm of the reaction mixture was read with a BioTek ELISA Reader (BioTek Instruments, Winooski, Vt.).
[0048] The culture supernatants from the positive wells were then tested for inhibition of classical pathway hemolysis of sensitized chicken RBCs by pre-titered human serum (3%) by the method described below. The cells in those positive wells were cloned by limiting dilution. The MAbs were tested again for reactivity with C2a and C2 in the ELISA. The selected hybridomas were grown in spinner flasks and the spent culture supernatant collected for antibody purification by protein A affinity chromatography. Ten MAbs were tested to be reactive with human C2a in ELISA. These MAbs are designated MAbs 175-50, 175-62, 175-97-1, 175-97-4, 175-101, 175-207, 175-283, 175-310, 175-322, and 175-326. As seen in FIG. 1 , MAb 175-62, MAb 175-101, MAb 175-207, MAb 175-310, MAb 175-322, and MAb 175-326 reacted strongly with human C2a in ELISA. In particular, MAb 175-62 shows the strongest reactivity with C2a among these binders. Interestingly, it binds weakly to immobilized C2 in ELISA.
Example 2
Inhibition of Complement-Activated Hemolysis
[0049] To study the functional activity of the anti-C2a MAbs in inhibiting complement activation in vitro, two hemolytic assays were used.
[0050] For the classical pathway, chicken RBCs (5×10 7 cells/ml), in gelatin/veronal-buffered saline (GVB ++ ) containing 0.5 mM MgCl 2 and 0.15 mM CaCl 2 , were sensitized with purified rabbit anti-chicken RBC immunoglobulins at 8 μg/ml (Inter-Cell Technologies, Hopewell, N.J.) for 15 minutes at 4° C. The cells were then washed with GVB ++ . The washed cells were re-suspended in the same buffer at 1.7×10 8 cells/ml. In each well of a round-bottom microtest plate, 50 μl of normal human serum (6%) was mixed with 50 μl of GVB ++ or serially diluted test MAb, then 30 μl of the washed sensitized chicken RBC suspension were added to the wells containing the mixtures. Fifty microliters of normal human serum (6%) was mixed with 80 μl of GVB ++ to give the serum color background. The final mixture was incubated at 37° C. for 30 minutes. The plate was then shaken on a micro-test plate shaker for 15 seconds, followed by centrifugation at 300×g for 3 minutes. Supernatants (80 μl) were collected and transferred to wells on a flat-bottom 96-well microtest plates for measurement of OD at 405 nm. The percent inhibition of hemolysis is defined as 100×[(OD without MAb−OD serum color background)−(OD with MAb−OD serum color background)]/(OD without MAb−OD serum color background).
[0051] The data in FIG. 2 show that the anti-C2a MAbs 175-62, 175-207, 175-310, 175-322, and 175-326 strongly inhibit classical pathway hemolysis. The anti-C5 MAb 137-76 also inhibits the hemolysis, but not the anti-factor D MAb 166-32, which is specific for inhibition of the alternative complement pathway.
[0052] The stoichiometric ratio of inhibition between MAb 175-62 and C2 in human serum by the classical pathway hemolytic assays was also measured as described above. Different molar ratios of MAb 175-62 to C2 were tested in the assays by combining normal human serum (containing 20 μg/ml or 0.2 μM of C2) with 0.4 μM, 0.2 μM, or 0.1 μM of MAb 175-62. The control was normal human serum treated with equal volume of GVB ++ . The mixtures were incubated at room temperature for 15 minutes. The mixtures were then serially diluted in GVB ++ . One hundred microliters of the diluted serum samples were added to each well of a round-bottom 96-well plate in duplicate. Thirty microliters of sensitized chicken RBCs were then added to each well for incubation as described above. The final mixture was incubated at 37° C. for 30 minutes. The plate was then shaken on a micro-test plate shaker for 15 seconds, followed by centrifugation at 300×g for 3 minutes. Supernatants (80 μl) were collected and transferred to wells on a flat-bottom 96-well microtest plates for measurement of OD at 405 nm.
[0053] The data in FIG. 3 show that the classical pathway hemolytic activity of C2 (0.2 μM) in normal human serum is completely inhibited when the serum was pre-treated with 0.1 μM of MAb 175-62. Therefore, MAb 175-62 inhibits human C2 at a molar ratio of 1:2 (Mab 175-62 to C2). In other words, MAb 175-62 is a very high-affinity anti-C2 antibody. Each of the two antigen binding sites in a molecule of MAb 175-62 can bind one molecule of C2.
[0054] For the alternative pathway, unsensitized rabbit RBCs were washed three times with gelatin/veronal-buffered saline (GVB/Mg-EGTA) containing 2 mM MgCl 2 and 1.6 mM EGTA. EGTA at a concentration of 10 mM was used to inhibit the classical pathway (K. Whaley et al., in A. W. Dodds (Ed.), Complement: A Practical Approach . Oxford University Press, Oxford, 1997, pp. 19-47). The procedures of the assay were similar to those of the classical pathway hemolysis as described above. The final concentration of human serum was 10%.
[0055] The data in FIG. 4 show that none of the anti-C2a MAbs inhibit the alternative pathway hemolysis, whereas anti-factor D MAb 166-32 effectively inhibits the hemolysis and anti-C5 MAb 137-76 moderately inhibits the hemolysis. Together with the results in FIGS. 2 and 3 , the anti-C2a MAbs have been shown to be specific for the classical complement pathway.
|
The invention relates to C2a inhibitors, which bind to C2a and block the functional activity of C2a in complement activation. The inhibitors include antibody molecules, as well as homologues, analogues and modified or derived forms thereof, including immunoglobulin fragments like Fab, F(ab′) 2 and Fv, small molecules, including peptides, oligonucleotides, peptidomimetics and organic compounds. A monoclonal antibody, which bound to C2a and blocked its ability to activate complement was generated and designated 175-62. The hybridoma producing this antibody was deposited at the American Type Culture Collection, 10801 University Blvd., Manassas, Va. 20110-2209, under Accession Number PTA-1553.
| 2
|
BACKGROUND OF THE INVENTION
This invention relates generally to a process for the treatment of oil-containing or oil-producing solids to extract fuel gases and liquid crude oil products therefrom. More particularly, the invention relates to a process for retorting arsenic-containing oil shale so as to produce a liquid shale oil which has a significantly lower arsenic content.
Vast deposits of oil shale, a sedimentary inorganic rock containing about 35 weight-percent calcite (CaCO 3 ), 15 weight-percent dolomite (MgCO 3 .CaCO 3 ), and 10 weight-percent alkali metal salts are known to exist in the United States, especially in the Green River formation in Colorado, Utah, and Wyoming. The oil shale in these deposits contains between 5 and 35 weight-percent of hydrocarbons in a form known as kerogen. When pyrolized, this kerogen decomposes to produce crude shale oil vapors, which, upon condensation, become a valuable source of fuel.
Several pyrolytic processes have heretofore been developed to produce crude shale oil from oil shale. One such process is shown in U.S. Pat. No. 3,361,644, which is incorporated herein by reference. In this process oil shale is fed upwardly through a vertical retort by means of a reciprocating piston. The upwardly moving oil shale continuously exchanges heat with a downwardly flowing, high-specific-heat, hydrocarbonaceous recycle gas introduced into the top of the retort at about 1200° F. In the upper section of the retort (the pyrolysis zone), the hot recycle gas educes hydrogen and hydrocarbonaceous vapors from the oil shale. In the lower section (the preheating zone), the oil shale is preheated to pyrolysis temperatures by exchanging heat with the mixture of recycle gas and educed hydrocarbonaceous vapors plus hydrogen. Most of the heavier hydrocarbons condense in this lower section and are collected at the bottom of the retort as a product oil. The uncondensed gas is then passed through external condensing or demisting means to obtain more product oil. The remaining gases are then utilized as a product gas, a recycle gas as hereinbefore described, and a fuel gas to heat the recycle gas to the hereinbefore specified temperature of 1200° F.
A problem with this and all similar oil shale retorting processes is that, during retorting, arsenic components present in oil shale either sublime to or are pyrolyzed into vaporous arsenic-containing components. As a result, arsenic in various forms collects with the educed hydrocarbonaceous vapors and condense with the heavier hydrocarbons in the preheating zone, or, in some processes, in a condenser situated outside of the retorting vessel. When oil shale obtained from the Green River formation is retorted, the concentration of arsenic in the produced crude shale oil is usually in the range of 30-80 ppmw. But since crudes containing such high concentrations of arsenic present problems in refining, especially with respect to poisoning hydrocarbon conversion catalysts used in catalytic cracking, hydrotreating, hydrocracking, reforming, etc., and since such oils also present an obvious pollution problem if burned without refining, the necessity for removing the arsenic from crude shale oil, or preventing its formation as vaporous components in the retorting zone, is clear.
However, presently available methods devised to produce an arsenic-free shale oil involve removing the arsenic from the liquid shale oil obtained from the retort. One such method is shown in my U.S. application Ser. No. 700,017 filed June 25, 1976, now U.S. Pat. No. 4,046,674 wherein arsenic-containing shale oil is contacted with an absorbent containing nickel sulfide, molybdenum sulfide, and alumina, under conditions of elevated pressure and temperature so as to obtain an arsenic-free shale oil. But although such a process is effective for removing arsenic from shale oil, it obviously would be more desirable to prevent the formation, or to minimize the amount, of vaporous arsenic components produced in the retorting zone. But no process for producing such a result is commercially available.
SUMMARY OF THE INVENTION
According to this invention, crushed oil shale about to be retorted in a conventional oil shale retort is admixed with at least sufficient of a nickel component additive so that in the resulting mixture of oil shale and additive the proportion of added nickel, as the metal, is at least 5 ppmw. When the mixture is fed to a retort wherein kerogen in the oil shale is pyrolyzed in a retorting zone at temperatures above about 600° F. to release shale oil vapors, the amount of vaporous arsenic also released in the retorting zone is reduced. Thus, the concentration of arsenic that will be present in the produced shale oil is reduced, with the concentration of arsenic in said shale oil decreasing with increasing proportions of added nickel in the shale-additive mixture fed to the retort.
As used herein, the terms "arsenic" and "arsenic components" are interchangeable and are intended to include arsenic in whatever form, elemental or combined, it may be present. Also, all oil shale and shale oil arsenic concentrations are herein calculated as elemental arsenic. Lastly, as herein calculated, the proportion of nickel additive in shale-additive mixtures is based on the weight of added nickel.
BRIEF DESCRIPTION OF THE DRAWING
The drawing shows a typical shale oil retort or retorting kiln in which a mixture comprising crushed oil shale and a nickel additive is passed countercurrently with an eduction gas through a retorting zone. Shale oil vapors released in the retorting zone are condensed in the preheating zone as an arsenic-free liquid shale oil.
DETAILED DESCRIPTION OF THE INVENTION
Any of a large number of naturally occurring, arsenic-containing, oil-producing solids can be used in this process. Typical of such solids are oil shales derived from the Green River formation, which usually contain 45-70 ppmw arsenic, or oil shales obtained from Morocco, which usually contain 10-20 ppmw arsenic. Regardless of the source of arsenic-containing shale, however, the shale should, for practical purposes, contain at least about 10, preferably at least 20, and usually between about 20 and about 80 gallons of oil per ton of raw shale by Fischer assay. Such shales when retorted will yield sufficient shale oil to justify the costs involved in retorting.
Referring now to the drawing, an arsenic-containing oil shale, crushed to particles no greater than 6 inches mean diameter, and preferably to particles no greater than 3 inches mean diameter, is fed at 2 with a nickel-containing additive into hopper 4 of shale feeder 6, the details of which shale feeder 6 are described in more detail in U.S. Pat. No. 3,361,644. The shale-additive mixture is forced upwardly by shale feeder 6 into retort 8 at a rate in excess of about 100, and preferably between about 400 and 2000, pounds per hour per square foot of cross-sectional area in the retort. These values refer to the average cross-sectional areas in the tapered retort illustrated in the drawing.
In retort 8, the shale-additive mixture traverses a preheating zone in the lower portion of retort 8 and a retorting (or pyrolysis) zone in the upper portion of retort 8. As the shale progresses upwardly through the retort, its temperature is gradually increased to retorting levels by a countercurrently flowing eduction gas comprising a preheated recycled portion of retort product gas from line 10. This product gas, and hence also the recycle gas, are of high BTU content, generally between about 700 and 1000 BTU/Ft 3 , and also of high specific heat, usually between about 14 and 18 BTU/mol/° F. Eduction temperatures in the retorting zone are conventional, usually in excess of about 600° F., and preferably between about 900° and about 1200° F. Essentially all of the oil will have been educed from the shale by the time it reaches a temperature of about 900° F. Gas temperatures above about 1300° F. in the retorting zone should not be exceeded since they result in excessive shale oil cracking. Other retorting conditions include shale residence times in excess of about 10 minutes, usually about 30 minutes to about one hour, sufficient to educe the desired amount of oil at the selected retort temperatures.
Pressure in retort 8 may be either subatmospheric, atmospheric, or superatmospheric. Retorting pressures normally exceed about 0.3 and are preferably between about 5 and about 1000 psia. The recycle gas is introduced via line 10 at a temperature and flow rate sufficient to heat the crushed shale to retorting temperatures. Heat transfer rates depend in large part on the flow rate, temperature, and heat capacity of this recycle gas. Flow rates of at least about 3000, generally at least about 8000, and preferably between about 10,000 and about 20,000 SCF of recycle gas per ton of raw shale feed are employed. The temperature differential between the recycle gas and solids at the top of the retorting zone is usually between 10° and 100° F. Excessive temperature differentials, e.g., in excess of about 400° F., should be avoided.
As the recycle gas from line 10 passes downwardly through retort 8, it continuously exchanges heat with the upwardly moving oil shale-additive mixture. In the upper portion of retort 8 oil contained within the oil shale is educed therefrom by pyrolysis, thereby producing shale oil vapors and fuel product gases comprising such normally uncondensable gases as methane, hydrogen, ethane, etc. These shale oil vapors and fuel product gases pass downwardly with the recycle gas, firstly into the lower portion (preheating zone) of retort 8 wherein the cool oil shale-additive mixture condenses the shale oil vapors, and thence into a frusto-conical product disengagement zone 12. This disengagement zone comprises peripheral slots 14 through which liquid shale oil and product gases flow into surrounding product collection tank 16. The liquid shale oil is withdrawn therefrom at a rate between about 5 and 60 gallons/ton of raw shale feed via line 18, while the aforementioned product gases at a temperature between about 80° and 300° F. are withdrawn via line 20.
The product gases are introduced into conventional venturi scrubber 22 wherein a liquid scrubbing medium is used to remove any remaining traces of water, shale oil vapors, and shale oil mist contained therein. The liquid scrubbing medium, after absorbing water and shale oil, is then sent via line 24 to conventional shale oil-water separation facilities (not shown), while the dry product vapors are sent to storage via lines 26 and 28 at a rate of 11,000 to 21,000 SCF/ton of shale feed. A portion of the product gases obtained in line 26 are passed by blower 30 and lines 26, 32, and 34 to preheater 36, wherein this portion of the product gases is heated to a temperature sufficient for retorting purposes in retort 8.
As product vapors are removed from retort 8 via line 20, the retorted oil shale overflowing the top of retort 8 falls onto inclined peripheral floor 38 of shroud 40, which is affixed in fluid-tight fashion to the outer wall of the retort. The retorted shale, now at a temperature between about 900° and 1300° F., preferably between about 900° and 1100° F., then gravitates down floor 38 into chute 42. From chute 42 the retorted shale may, by facilities not shown, be passed to a combustor wherein coke on said retorted shale is burned to produce a heated flue gas for use as a heat exchange medium in preheater 36. Alternatively, the retorted shale may be contacted with steam to further remove shale oil or product gas vapors. And alternatively still, the retorted shale may simply be discharged to a waste ash heap.
The critical feature of the invention as thus far described is the addition of a nickel-containing additive with the oil shale entering the retort. To obtain uniform distribution and intimate contacting of additive and shale rock, the additive is preferably introduced into the raw shale by spraying a solution of a nickel component into the shale particles about to be fed into hopper 4. The solution sprayed onto the shale particles should, in accordance with the invention, contain at least 0.10 grams of nickel per liter, and preferably at least 0.50 grams of nickel per liter. It is most highly preferred, however, that the solution contain between about 1 and 10 grams of nickel per liter.
The solutions of nickel components suitable herein may be organic or inorganic in nature. However, aqueous solutions of inorganic nickel compounds, such as aqueous solutions of such highly water-soluble nickel compounds as nickel chloride, nickel nitrate, and nickel sulfate, are preferred. Suitable aqueous solutions include aqueous, ammoniacal solutions of basic nickel carbonate (NiCO 3 .2Ni(OH) 2 .4H 2 O), and other aqueous solutions in which a water-insoluble nickel compound (or nickel itself is dissolved.
In the preferred mode of operation, the shale particles are sprayed so as to just wet the surfaces thereof with the aqueous, nickel-containing solution. Preferably, the resulting mixture of oil shale and additive contains at least 5 ppmw of added nickel, and most preferably between about 10 and 100 ppmw of added nickel. When the shale is so treated, and is then subjected to retorting in retort 8, the amount of arsenic released from said shale in vaporous forms is substantially reduced. Thus, the amount of arsenic which will collect with the produced shale oil will be minimized, and the concentration of arsenic in said shale oil is substantially less than that obtainable when no additive is utilized. For a typical shale obtained from the Green River formation, a reduction in the concentration of arsenic in the produced shale oil of at least 30% is obtainable when the oil shale contains about 15 ppmw of added nickel. And when the same shale contains higher proportions of added nickel, the concentration of arsenic in the produced shale oil is reduced still further, often by at least 75%, with the reduction of arsenic in the shale oil increasing with the increased proportions of added nickel.
The following example is provided to illustrate the invention.
EXAMPLE
Three 751-gram samples of oil shale obtained from the Green River formation in Colorado were crushed to less than 3/8-inch mean diameter granules. One sample was wetted with an ammoniacal solution of nickel carbonate (0.018 grams NiCO 3 .2Ni(OH) 2 .4H 2 O in 50 ml of 1.0 N NH 4 OH) so that the shale-additive mixture contained 11 ppmw nickel (as nickel). A second sample was wetted with aqueous nickel nitrate (0.0438 grams Ni(NO 3 ) 2 .6H 2 O in 10 ml water) so that the shale-additive mixture contained 12 ppmw nickel (as nickel). The third sample was admixed with no additive.
The following experiment was then performed on each sample individually. The sample was supported as a 16-inch column in a 2-inch diameter, 5-foot long, stainless steel tube. A synthetic retort product gas, dehydrated to a water vapor dewpoint of 100° F., and consisting, on a dry basis, of 28.3 mole percent H 2 , 50.0 mole percent CH 4 , 2.3 mole percent H 2 S, 7.0 mole percent CO, and 12.5 mole percent CO 2 , was then passed downwardly through the tube. The tube itself was gradually pushed upwardly through a furnace maintained at about 1000° F. such that any gradient of shale in the tube took 1 hour to heat up to 1000° F. and was maintained at 1000° F. for 1 hour. The educed shale oil vapors were condensed in a condenser situated external to the stainless steel tube, and the collected shale oil was analyzed for arsenic. These data and other data obtained in the three experiments are recorded in the following Table.
TABLE______________________________________Test No. 1 2 3______________________________________Additive Solution None NiCO.sub.3 . 2Ni(OH).sub.2 Ni(NO.sub.3).sub.2Added Nickel inmixture, ppmw 0 11 12Collected ShaleOil gm 67 67 84Arsenic in collectedshale oil afterfiltration ppmw 13 7.1 8.6Arsenic in collectedshale oil afterfiltration and extrac-tion in 2 N NH.sub.4 OH 8.2 6.1 5.2______________________________________
Although the invention has been described in conjunction with a specific example thereof, it is evident that many alterations, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and scope of the appended claims.
|
The concentration of arsenic in shale oil produced from retorting arsenic-containing oil shale in a conventional retorting kiln is reduced by blending with said oil shale a nickel-containing additive. During retorting, the amount of arsenic released in vaporous form from the oil shale is reduced, thereby decreasing the amount of arsenic which collects with the produced liquid shale oil. Thus, a shale oil is produced having a significantly lower arsenic content than is obtainable without the use of the nickel additive.
| 2
|
BACKGROUND OF THE INVENTION
This invention concerns control of the atmosphere in an operator enclosure of a self-propelled vehicle and, more particularly, the arrangement and combination of components within the enclosure of an off-the-road vehicle exposed to heavy concentrations of airborne dust and debris.
Concern for operator safety and comfort leads to the development of increasingly sophisticated operator enclosures (which, however, are still generally referred to as cabs). It is well-known that modern cab design deals not only with ergonomic considerations but also with the more passive environmental factors such as roll-over protection, isolation from noise and preservation of a comfortable and clean atmosphere. The present invention is concerned principally with the latter but improvement of atmosphere control in cabs is clearly most advantageously used in an operator station or enclosure in which other comfort and safety considerations have been adequately provided for. It is well-known, in a completely encloed cab, to provide an atmosphere control system which takes in and filters outside air, heats or cools the air as required, and circulates it in the cab while maintaining pressure in the cab slightly above atmospheric, so as to discourage the entry of dust or other contaminants through, for example, imperfectly sealed doors or windows. Efforts are still being made to improve the efficiency, serviceability and compactness of such systems. Means are sometimes provided for precleaning the intake air but typically precleaners are remote from the main components of the system and unsightly and fitted as an attachment or add-on rather than integrated into the system.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide for the operator enclosure of an off-the-road self-propelled vehicle, such as an agricultural tractor or combine, an atmosphere control arrangement which is compact, convenient to assemble, service and repair, and which is efficient in operation.
It is a feature of the invention to arragne all principal components in series with a view to efficiency in operation and simplicity of housing and ducting the components. In a preferred embodiment, there is a single (preferably elevated) inlet for fresh air intake and essentially a single outlet for circulating and pressurizing air combined. The system sequence is as follows: fresh air inlet, pressurizing blower, precleaner, fresh air filter, heat exchanger, circulating blower. Features which modify the simple series arrangement may include the precleaner being of the inertial (preferably translational) type in which case dust or dirt extracted is exhausted or ejected to atmosphere while the bulk of inlet air passes on to the fresh air filter. Another modifying feature may be the provision of a filtered inlet for admitting recirculated air into the system, upstream of the heat exchanger. Preferably the outflow of combined circulating and pressurizing air from the circulating blower will be distributed appropriately in the enclosure by suitable ducting. It will be understood that the incoming fresh air delivered by the pressurizing blower functions not only to maintain a positive pressure within the enclosure but also to make up air intentionally lost through "leaks" in the enclosure. Make-up air is required to maintain an acceptable level of air quality.
The simplicity of the series arrangement of components facilitiates the provision of a split housing for the components comprising principally upper and lower halves mating or meeting at a generally horizontal parting line. The lower half may be seated on the floor of the operator enclosure and may include molded forms for positioning and support of components such as the heat exchanger and recirculating air filter and precleaner, final completion of assembly and retention of components in place being made by placing the upper casing half in position.
It is a feature of the invention that a generally upstream compartment of the housing, defined locally by internally projecting portions of the upper and lower casing halves, may contain the precleaner and have, in one of its walls, an aperture covered by the main fresh air filter of the system. Preferably this filter compartment includes a wall adjacent or coincident with an external wall of the operator enclosure thus facilitating service access to the filter compartment. Preferably, molded and vertically aligned features in the upper and lower portions of the casing respectively receive and hold the precleaner with its inlet and bleed air outlet registering with opposite apertures in the casing. Thus the principal axis of air flow in the precleaner is vertically aligned and a dust and dirt outlet is readily provided in the floor of the operator enclosure. Preferably the pressurizing blower has an air delivery outlet directed downwards and communicating directly with the precleaner so that charging of the precleaner is direct and efficient.
Other objects and advantages of the invention will become apparent from reading the description which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a left-hand side elevation of an operator enclosure embodying the invention.
FIG. 2 is a simplified schematic of the atompshere control system based on a rear view of the operator enclosure of FIG. 1. The spatial relationship of components have been modified somewhat to simplify this representation of their functional relationships.
FIG. 3 is an enlarged overhead view of the rearward lower portion of the operator enclosure showing the general arrangement of the system within the enclosure.
FIG. 4 is a partial, generally front view approximately on line 4--4 of FIG. 3.
FIG. 5 is a partial rear view approximately on line 5--5 of FIG. 3 showing the pressurizing blower and precleaner.
FIG. 6 is a view approximately on line 6--6 of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention is embodied in the operator's station and enclosure of a self-propelled combine harvester shown in FIG. 1.
The enclosure is generally rectangular in shape and includes a floor 10, rear wall 12, opposite side walls 14 and a roof 16. There is an access door 18 in the left-hand side wall 14. The operator station includes a seat 20 supported on a seat pedestal 22, a steering column 24 and various controls and equipment not shown in the drawing.
The general dispostion of the enclosure atmosphere control system 30 is indicated in FIG. 1. The bulk of the system is supported on the floor 10 of the enclosure close to the rear wall 12. Clean make-up air for the system enters through louvers 32 in the roof 16 into a plenum 34 and thence by a duct 36 extending vertically downwards close to the rear left-hand corner of the enclosure, to broaden into a blower plenum area 38 immediately above the atmosphere control system 30.
The sequential and functional relationship of the principal components of the atmosphere control system are shown schematically in FIG. 2. This drawing is semi-pictorial but the orientation and disposition of some of the components has been changed somewhat for clarity. Casing 40 essentially houses all the main components including a pressurizing blower 42, precleaner 44, fresh air filter 46, heat exhanger 48, recirculating blower 50 and connects with distribution ducting 52. The heat exchanger 48 includes an evaporator (air conditioning) 54, a heater coil 56 and an adjustable air deflector or baffle 58. Recirculating air is admitted to the casing 40 through a recirculating air filter 60 into an air mixing chamber 62, downstream of the fresh air filter 46.
FIGS. 3 and 4 show the actual configuration of the system, supported on the floor 10 of the cab in the left-hand rear corner immediately to the left of the operator seat 20. As can be seen, the principal components, fresh air filter 46, heat exchanger components 48 and the recirculating blower 50 are substantially coaxial and the longitudinal axis of the system extends approximately diagonally with respect to the floor 10 of the cab.
FIGS. 3 and 4 particularly illustrate the compactness of the system and indicate the covenience and simplicity of assembly and service provided by the generally horizontally split or divided casing 40 which consists essentially of upper and lower portions 64 and 66, respectively, meeting at a flanged and bolted joint 68. The lower portion 66 is mounted on the floor of the cab by suitable fasteners (not shown) and, in common with the upper portion 64, it has appropriate recesses suitably molded to position and support the various components of the system. An example is the support of evaporator 54 in recesses 65 and 65a (FIG. 4).
In assembly, internal flange-like members define a transverse wall 70 with a through aperture 72 for mounting the cylinder-type fresh air filter 46. The internal space of the casing upstream of the wall 70 will be referred to as a filter chamber 74. The precleaner 44 also extends vertically through it, immediately rearward of the fresh air filter 46. The upstream end of the casing 40 connects with the left-hand side wall 14 and an access door 76 provides convenient access from outside of the cab to the filter chamber 74.
The precleaner 44, seen best in FIGS. 5 and 6, is of the translational inertial type, the general principles of which are described in Society of Automotive Engineers paper 880B, "High Performance Air Cleaners for the Army's Industrial Gas Turbines" presented in 1964(see especially pages 3-6). It is positioned by and supported between a pressurizing blower nozzle or outlet 80, molded into the upper casing portion 64, and an open recess 82 molded into the floor of the lower casing position 66. The precleaner 44 is essentially a tapered passage of rectangular cross section in which opposite body walls 84 are louvered, with louvers 86 extending laterally and defining a series of upwardly and outwardly directed slots 88. A top transitional portion 90 connects with the pressurizing blower 80 and an exit slot 92 connects with a downwardly directed outlet 94 in the recess 82 in the floor 10 of the cab. The lower outlet end of the precleaner 44 is supported in the recess 82 on a resilient gasket or grommet 96. This serves as a compression "spring" permitting insertion of the precleaner 44 and holding it in place, with a collar 98 engaging the blower nozzle 80. It is thus conveniently removable for service or replacement.
In operation, the cab door 18 is closed and pressurizing blower switched on drawing outside air in through the roof louvers 32. These louvers screen out larger pices of airborne trash, leaves, etc., but, typically, dust-laden air enters and is delivered downwards, "charging" the precleaner 44. The way in which translational inertial precleaners operate is wellknown. The relatively high axial air velocity developed carries dust and dirt downwards at such velocity that the particles have sufficient inertia to resist the deflection and near reversal of direction it would require to pass through the slots 88. The tapered form of the precleaner helps maintain the air velocity and also develops a static pressure so that much of the air delivered by the blower 42 passes through the louvered slots 88 into the filter chamber 74. In a typical precleaner of this type, about 15 percent of the initial flow of air is lost or bled. In this embodiment it exits vertically downwards through the slot 92 and outlet 94 in the floor 10 of the cab taking with it 80 to 95 percent of the dust which had been entrained in the incoming air.
As is conventional the cab structure is designed to "leak" at a rate which requires a make-up air flow sufficient to maintain air quality in the cab at an acceptable level.
Normally, the pressurizing blower 42, preferably of the constant volume type, runs continuously when the combine is operated with the cab closed. When the recirculating blower 50, preferably variable speed, is also in operation, air from inside the cab is drawn through the recirculating filter 60 to mix with fresh or make-up air passing from the filter chamber 74 through the fresh air filter 46 into the mixing chamber 62. The combined air then passes throuh heat exhanger 48 and is conditioned (heated or cooled and possibly dehumidified) according to setting of conventional controls (not shown). Conditioned air is then distributed appropriately in the cab by the distribution duct 52.
Among advantageous features of an operator enclosure atmosphere conditioning system according to the invention, and evident from the drawings and above description are the compact space saving and functionally efficient disposition and layout of the principal components. The "in-series" arrangement of principal components means that all air is drawn through the system with mimimum pressure loss and turbulence. The unobtrusive integration of the precleaner 44 achieved by placing it alongside the fresh air filter 46 in the filter chamber 74 enhances the convenience of the location of the main fresh air filter 46. Both the filter and precleaner may be insepected or serviced conveniently through a single access door 76. The inconvenience of the typically bulky and unsightly external precleaner is avoided. Here, is is completely concealed and is self-cleaning, and its location is such that dust and dirt extracted by it is discharged downwards relatively close to the ground with a reduced possibility of fouling other parts of the combine.
|
An atmosphere control system for the cab of a self-propelled combine has its principal components arranged for series flow and mounted compactly on a rear portion of the floor of the cab. A pressurizing blower injects fresh air into an upstream filter chamber through a translational inertial precleaner which discharges any removed dust along with bleed air vertically downwards through the floor of the cab. A filter further cleans fresh air as it continues into the system, to pass through a heat exchanger and into circulation by a circulation blower and suitable ducting. Both precleaner and fresh air filter are accessible through a door in an outside wall of the cab.
| 1
|
FIELD OF THE INVENTION
This invention relates to sliding tables for use in conjunction with any machine or workbench that is used for doing mechanical or practical work. More particularly the invention relates to a sliding table for use in conjunction with a workbench or a machine such as a table saw, router table, shaper, drill press, band saw or workbench. The sliding table has means for accurately guiding the movement of the table and minimizing rocking of the table on its longitudinal and transverse axes.
BACKGROUND OF THE INVENTION
Sliding tables for workbenches are known for providing lateral support to a piece of work or stock in front of or behind the workbench. Such tables usually travel on a path which is perpendicular to the longitudinal axis of the workbench. The path extends from in front of the workbench to behind it and, in general, the longer the path, the more useful and versatile the table is. However the table become increasing unstable as the path lengthens. That is because the longer the path, the larger the portion of the table that is cantilevered when the table is at the ends of its travel. The cantilevered portion is not supported and for that reason is relatively unstable. Any weight on the table may cause the machine or workbench to tip over or may cause the table to bend or fracture.
I have found a way of significantly extending the length of travel of a sliding table while at the same time providing improved control and guidance of a piece of work on the sliding table. The way in which I do so involves the use of, among other things, a movable carriage on which the piece of work is located. I also use spring-loaded rotating means such as rollers. Alternatively, bearing plates apply pressure to rollers for accurately guiding the table while it is sliding so that precise work can be carried out on the table.
SUMMARY OF THE INVENTION
Briefly, the sliding table of my invention is used for guiding a work piece including: a bed adapted to be immobilized and a carriage movable relative to the bed and having a surface upon which the work piece is adapted to be located. Either the bed or the carriage has rotating means and the other has a track in which the rotating means revolves. Resilient means is provided for causing the rotating means and the track to be biased toward each other.
DESCRIPTION OF THE DRAWINGS
The sliding table of the invention is described with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of the sliding table in conjunction with a table saw;
FIG. 2 is a plan view of the sliding table and table saw;
FIG. 3 is a perspective view of a bed of the sliding table;
FIG. 4 is an enlarged fragmentary perspective view of the bed;
FIG. 5 is a fragmentary perspective view of the carriage which slides on the bed;
FIG. 6 is a section of a portion of the carriage;
FIG. 7 is a enlarged fragmentary perspective view of the carriage and bed;
FIG. 8 is an elevation of the components illustrated in FIG. 7 from the front;
FIG. 8 a is an elevation of the bed and carriage in which the carriage is provided with rollers and the bed is provided with a track.
FIG. 9 is an elevation a portion of the bed from the side showing two rollers on which the carriage slides;
FIG. 10 is an exploded perspective view of the components of one of the rollers of a second embodiment of the sliding table;
FIG. 11 is a sectional view of the roller illustrated in FIG. 10 in conjunction with a sectional view of a portion of the carriage adjacent to the roller.
Like reference characters refer to like parts throughout the description of the drawings.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1 and 2 , the sliding table of the invention, generally 10 , is shown in conjunction with a table saw, generally 12 . The table saw is conventional and consists of a housing 14 and an upper panel 16 having a working surface 18 through which a circular saw blade 20 projects. An electrical box 22 having on-off switches control the operation of the saw.
The sliding table includes a bed, generally 30 and an upper carriage, generally 32 which is mounted for sliding on the bed.
With reference to FIGS. 1 and 3 , the bed is provided with a bracket 34 having a vertical leg 34 a which is bolted to the side edge 36 of the table saw and a lower horizontal leg 34 b on which a roller assembly, generally 38 , is mounted.
With reference to FIGS. 3 and 4 , the roller assembly includes a framework 40 to which a number of rollers 42 are mounted for rotation. The rollers are arranged in groups of six spaced along the length of the framework. A pair of rollers 42 a in each group is disposed centrally between the other rollers in the group and rotates about a vertical axis 44 - 44 . The remaining rollers 42 b in the group are arranged outwardly of the central rollers. The outer rollers are arranged in pairs on opposite sides of the central rollers and rotate about a horizontal axis 46 - 46 .
The framework has a central longitudinally extending I-shaped segment 50 . The central rollers 42 a are mounted for rotation on lower horizontal wall 50 a of the I-segment and extend through openings in its upper horizontal wall 50 b . On opposite sides of the central I-segment and spaced apart therefrom are distal I-shaped segments 52 . The outer rollers 42 b are mounted for rotation to the inner vertical walls 52 a of the distal segments and extend through openings in its outer vertical wall 52 b.
The spaces between the central and distal I-segments, marked by arrows 54 , constitute two parallel longitudinally extending slots or tracks for receipt of downwardly extending flanges 56 a,b formed on the carriage. The flanges are shown in FIG. 5 and are described in detail below.
With reference to FIGS. 5 and 6 , the carriage is provided with an upper wall 60 with an upper surface 62 which is flush with the working surface 18 of the table saw. Grooves, generally 64 , 66 , are formed in the upper wall. The grooves which are horizontally spaced and longitudinally extending are provided to accommodate a fence. An example of such a fence is described in my co-pending applications for patents filed in the United States Patent & Trademark Office under Ser. No. 10/678,228 and in the Canadian Intellectual Property Office under serial no. 2,444,371. Both applications were filed on Oct. 6, 2003.
The flanges 56 a,b are spaced apart from one another and each is made up of a downwardly extending vertical limb 70 and a short horizontal limb 72 at the lower end of the vertical limb. The side walls of vertical limbs which face one another define opposite sides of a track, generally 74 . On the inside wall of flange 56 a is a pair of vertically spaced longitudinally extending grooves 76 . Each groove receives an elongated strip 78 of rubber, O-ring cord stock or like deformable flexible material.
A longitudinally extending groove 80 is also formed in the horizontal limb 72 of flange 56 a and a second longitudinally extending groove 82 is formed in the lower surface of wall 60 . Groove 82 is vertically above groove 80 and both grooves receive a vertically extending bearing plate 84 . The bearing plate extends the length of the carriage and is biased outward by the resiliently deformable strips 78 .
Flange 56 b also has a bearing plate 84 mounted in grooves in the flange. The two bearing plates in flanges 56 a,b face one another and the space between them defines the side wall boundaries of track 74 in the carriage.
Flanges 56 a,b are arranged centrally of the carriage. Disposed outwardly of the central flanges are distal flanges 90 a,b . With reference to FIGS. 5 and 6 , the distal flanges are also L-shaped but their lower horizontal limbs 94 are longer than those of flanges 56 for accommodation of a pair of parallel grooves 96 . The latter grooves receive elongated strips 98 of resiliently deformable material.
Horizontally opening grooves 100 in each distal flange receive a bearing plate 102 which is biased outwardly by resiliently deformable strips 98 . Vertically above the bearing plate 102 is another bearing plate 104 mounted in a groove in a short flange 106 and in the vertical limb 108 of the distal flange. The two bearing plates 102 , 104 face one another and the space between them forms a outer track 110 in the carriage. The upper side face 102 a of the bearing plate is in contact with the roller within track 110 . The oppositely facing lower side face 102 b of the bearing plate faces grooves 96 in which the strips of resiliently deformable are located.
With reference to FIG. 8 , the central rollers 42 a are received in central track 74 in the carriage such that the outer walls of the rollers contact the bearing plates 84 on opposite sides of the rollers. Similarly outer rollers 42 b are received in tracks 110 such that their outer walls contact bearing plates 102 , 104 .
FIG. 8 a is the same as FIG. 8 except that rollers 42 a,b are provided on the carriage while the track 74 is provided in the bed. The bed is attached to the side edge 36 of the workbench while the carriage is floating.
In operation and with reference to FIG. 9 , the bearing plates, biased by the strips of resiliently deformable material, minimize rocking of the carriage on its longitudinal axis 142 . In that Figure the carriage has rocked clockwise and the upper wall of roller 42 d bears against the upper bearing plate 142 while the lower wall of roller 42 e bears against the lower bearing plate 146 and causes it to deform slightly. The resiliently deformable strips behind the two bearing plates will resist such deformation and will urge the plates to return to their undeformed state. As the plates return. they will dampen the rocking movement of the carriage.
In like manner and with reference to FIG. 7 , central rollers 42 a minimize rocking of the carriage on its transverse axis 148 - 148 since such rocking will force some of the central rollers into contact with the bearing plate behind which the resiliently deformable strips are located. The strips will resist deformation of the bearing plates and will urge the plates to return to their undeformed state. Lateral movement will be dampened by such movement.
In the embodiment of the sliding table just described, bearing plates biased by the strips of resiliently deformable material dampen the rocking of the carriage. In the second embodiment of the invention described below, the rollers are spring loaded and it is they that dampen the rocking of the carriage.
With reference to FIGS. 10 and 11 , roller 42 c is connected to eccentric 120 and the eccentric in turn is connected to a threaded shank 124 . The shank passes through an opening 126 in wall 128 of the framework and is held to the plate by means of nut 130 . The nut prevents the shank from withdrawing from wall 128 but does not prevent the shank from pivoting relative to the wall. A coil spring 132 encircles the shank and one of its ends is received in an opening 134 in the wall while the other end engages the outer wall of the shank. The spring urges the shank to pivot clockwise and as the shank pivots, the roller is urged in the direction of the arrow in FIG. 11 into contact with bearing plate 140 .
It will be understood that the rollers of FIGS. 10 and 11 may be substituted for the rollers of the preceding FIGS. 1 to 9 in which case pressure plates and rubber strips may be dispensed with. The carriage will resist rocking in both the longitudinal and lateral directions.
The rollers are biased into pressure plate 140 of the track 142 . Alternatively, the pressure plate may be provided on the carriage in which case the rollers are provided on the track.
It will be understood, of course, that modifications can be made in the embodiments of the invention illustrated and described without departing from the scope and purview of the invention as set in the appended claims.
|
The sliding table has a stationary bed and a carriage which is movable relative to the bed. The carriage has an upper surface on which a work piece is seated. The bed has rollers and the bed has a track. Alternatively, the bed has a track and the carriage has rollers. In either case, the rollers roll back and forth in the track. Either the rollers are biased into contact with the track or the track is biased into contact with the rollers. In the former case, an eccentric and a coil spring are used to bias the rollers. In the latter case, the track has a bearing plate which is biased by a rubber strip or O-ring cord stock into contact with the rollers.
| 5
|
RELATED APPLICATIONS/PRIORITY BENEFIT CLAIM
[0001] This application claims the benefit of U.S. Provisional Application No. 61/723,076, filed Nov. 6, 2012 by the same inventor (Halek), the entirety of which provisional application is hereby incorporated by reference.
FIELD
[0002] The subject matter of the present application is in the field of electroluminescent wire displays for bike wheels, and in particular devices for securing such wire to a bike wheel.
BACKGROUND
[0003] Many devices for illuminating bicycles (bikes) at night are known. One example is the Bikeglow™ safety light, consisting of an electroluminescent wire and a battery power unit adapted to be mounted on a bike. Normally the wire is wound around portions of the bike frame, away from moving parts and cables; however, I have seen the electroluminescent wire taped to the spokes of a bike wheel, with the power unit secured to rotate with the wheel between the spokes.
[0004] The Revolights™ bike lighting system consists of two narrow rings of LEDs that mount directly to each wheel using a series of clips and ring spacers. The clips are three-part clips, each clip having a spoke-clamping base with a screw-receiving bore and a slot that snaps loosely over a spoke, a cross-bar adapted to be secured to the spoke-clamping base with a screw, and the screw. The spoke-clamping base rotates loosely around the spoke until the cross-arm is tightened in place with the screw, activating the clamping halves of the base to frictionally lock it against rotation on the spoke. The cross-arm is sized to span the wheel width, and the ends of the cross-arms include screw-receiving bores so that slotted portions of the LED rings aligned over the rims on each side of the wheel can be fastened to the clips with screws.
[0005] While the Revolights™ LED rings produce a useful ground level headlight/taillight effect at the leading/trailing edges of the front and rear wheels, in addition to side illumination for visibility by others, the multi-part clips are relatively complicated to manipulate and secure to the spokes, and the LED rings and associated hardware needed to align, install, and operate the lights make a system that is unnecessarily complicated and expensive for simple side illumination of the wheels.
BRIEF SUMMARY
[0006] I have invented a spoke clip especially for mounting electroluminescent and equivalent lighted wire to the spokes of a bike wheel. My invention in a first aspect is the clip itself, and in a second aspect is the combination of the clips and the resulting illuminated wire array secured to the bike wheel with the clips.
[0007] My clip is a generally L- or T-shaped clip with a spoke-engaging stem and an integral wire-mounting arm generally perpendicular to the stem. The stem is split by an open-ended slot running from the outer end of the stem toward the junction of the stem and the wire-mounting arm, the slot dividing the stem longitudinally into flexible halves and oriented generally perpendicular to the wire-mounting arm. The slot has an initial width at its outer end narrower than the diameter of a spoke, and terminates at its inner end in a spoke nut socket having a second width greater than the diameter of a spoke and approximately equal to, and preferably slightly less than, the width of a spoke nut, sufficient for a snug fit. The wire-mounting arm includes at least one open-ended wire slot sized to securely receive and hold a wire on an axis generally parallel to the spoke-engaging stem.
[0008] When the clip is applied to a spoke, the spoke nut socket radially receives and loosely engages the spoke. Sliding the clip outwardly to the wheel rim along the spoke causes the spoke nut socket to axially mate with and tightly engage the spoke nut. The result is that the clip can be rotated freely when initially mounted on a spoke, but resists rotation when engaged with the spoke nut.
[0009] In its second aspect, the clip is mounted on a spoke nut, and rotated to a wire-engaging position in which the stem is generally parallel to the plane of the wheel, and in which the wire-mounting arm is generally perpendicular to the plane of the wheel. An electroluminescent (EL) wire is clipped to the slot in the wire-mounting arm, which positions the wire relative to the adjacent spokes, running generally in or parallel to the plane of the wheel. Mounting multiple clips around the wheel allows the wire to be mounted in whatever pattern desired in a plane generally parallel to the plane of the wheel, positioned close to the spokes.
[0010] The resulting illuminated display on the bike wheel is more secure, more aerodynamic, and provides a more steady or solid light pattern (without flickering) than prior art devices and systems. The resulting illuminated display is just as visible when stationary as when moving.
[0011] These and other features and advantages of the invention will become apparent from the detailed description below, in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an exploded assembly view, in perspective, of an exemplary clip according to the present invention being installed on a spoke.
[0013] FIG. 2 is an opposite perspective view of the clip of FIG. 1 .
[0014] FIG. 3 is a stem end view of the clip of FIG. 1 .
[0015] FIGS. 4A and 4B are top views of clips installed on successive spokes of a bike wheel, sectioned through the spokes, showing different ways of guiding the wire from spoke to spoke.
[0016] FIG. 5 is a side elevation view of the bike wheel with an array of clips according to FIG. 1 , supporting lighted wire on the side of the wheel and showing a wire control/power box secured to rotate with the wheel.
DETAILED DESCRIPTION
[0017] Referring first to FIGS. 1 through 3 , a spoke clip 10 is shown in exemplary form in order to teach how to make and use the claimed invention. Spoke clip 10 is designed to be attached to the spokes 22 of a bike wheel 20 , and in particular to be secured in use to the spoke nuts 24 that join the spokes to the rim 26 of the wheel. Bike wheel 20 in the illustrated example should be understood to represent primarily bicycle wheels, but also scooter, motorcycle, and other types of similarly-spoked wheel, without limitation.
[0018] Spoke clip 10 includes a spoke-mounting stem 12 and a wire-holding arm 14 generally perpendicular to the stem. Although clip 10 is illustrated as a generally T-shaped clip capable of holding two wires, one on each side of the stem, it will be understood that generally L-shaped clips for holding a single wire are also possible. FIG. 2 shows one of the wire-holding arms 14 in phantom, such that the solid line portion of the drawing represents such an L-shaped clip.
[0019] Wire-mounting arm 14 is integral with stem 12 , in that they are a single piece not requiring assembly at the point of application to the spokes of a bike wheel. The entire clip is preferably molded from a plastic material such as nylon or polypropylene that tends to deform rather than break when stressed; other suitable materials may be known to those skilled in the art, including relatively soft metals or metals with deformable inserts capable of a friction fit with a spoke nut. While molding is the preferred method of manufacture, other methods of forming clip 10 are possible, depending on the material used, including but not limited to machining or casting.
[0020] Still referring to FIGS. 1 through 3 , the stem 12 of clip 10 is split into two flexible longitudinal sections by a slot 13 , the slot divided into two regions: a narrower entry region 13 a whose width is less than the width of a spoke 26 , and a wider socket region 13 b at its terminal end adjacent the junction of stem 12 and wire-holding arm 14 . The socket region defines a nut socket 13 b whose diameter or width (depending on its cross-section and material) is sized approximately equal to and preferably slightly smaller than the spoke nut for a snug axial and radial friction fit over spoke nut 24 , so that the clip resists rotation around the nut and also resists sliding axially off the nut down onto the spoke.
[0021] The wire-mounting arm 14 of clip 10 ends in open wire-mounting slots 17 , having narrower entry portions 17 a smaller than the diameter of the EL wire and larger terminal portions 17 b approximating the diameter of the wire. The axis of terminal portions 17 b of the slots is generally parallel to the axis of stem 12 .
[0022] Spoke nuts such as 24 tend to have square cross-sections, although spoke nuts with circular cross-sections, or with half-square/half-round sections 24 a ; / 24 b ( FIG. 1 ) are also known. In the illustrated example, socket 13 b has a circular cross-section, which in combination with the use of a deformable plastic material for the clip body (for example, nylon or polypropylene) has been found to produce a secure frictional fit over either square or round spoke nuts whose width or diameter is slightly greater than the diameter of socket 13 b. It would also be possible to form socket 13 b with a polygonal (e.g. square) cross-section to mate with the shape of a particular style of polygonal spoke nut, but in such a case the dimensions of the socket should still be at least slightly less than the dimensions of the nut for a snug axial fit.
[0023] In FIG. 1 , clip 10 is first shown clipped over the spoke 22 , radially inwardly of spoke nut 24 (upper phantom lines), and then moved down the spoke into frictional engagement with the spoke nut (lower phantom lines). Clip 10 is also rotated to put stem 12 in alignment with rim 26 and to put wire-mounting arm 14 perpendicular to the plane of the wheel, preferably before engagement with the spoke nut depending on the relative dimensions of the socket 13 b and the nut and the tightness of the fit between them.
[0024] The initial fit of clip 10 over spoke 22 is rotationally and radially loose, allowing the clip to rotate freely on the spoke, and to slide up and down the spoke, while preventing the clip from popping off the spoke axially without a significant, intentional pull in the direction from which it was applied. The final fit of clip 10 over the spoke nut 24 is rotationally, radially, and axially tight, resisting rotation of the clip around the spoke nut, sliding of the clip off the spoke nut onto the spoke, and pulling or popping of the clip off the spoke nut (and off the wheel).
[0025] FIG. 2 shows approximately half of the wire-mounting arm 14 in phantom, illustrating the option in solid lines of a generally L-shaped clip rather than a T-shaped clip. It should be understood that the terms L-shaped and T-shaped are to be understood approximately and generally and not in a limiting sense, and that the illustrated shape and proportions of the clip stem 12 (rounded) and the wire-mounting arm 14 (flat) are not limiting, but represent a currently preferred example.
[0026] FIGS. 4A and 4B illustrated clips 10 mounted on successive spokes 22 of a wheel 20 . In FIG. 4A , clips 10 each support two wires 30 , one wire on each side of wheel 20 running in a straight line from clip to clip, and remaining on the outside of the spokes. In FIG. 4B , each clip supports one wire, and the wire is woven around successive spokes from side to side of the wheel. Other examples and patterns are also possible, whether using one or two wires and whether using T-shaped (two-wire holding) or L-shaped (one-wire holding) clips 10 . The wire-mounting arm 14 extends laterally beyond adjacent spokes 22 , but preferably has a length less than the width of the wheel rim, so that it remains within the width of wheel rim 26 in order to prevent contact with other parts of the bike when the wheel rotates.
[0027] In general, however, the wire 30 clipped to the spokes can be considered to form a generally planar illuminated array in the plane of the wheel, whether limited to the outside of the spokes on one side of the wheel or woven back and forth across the rim centerline from spoke to spoke. The alignment of the wire 30 between clips 10 will also vary somewhat depending on the alignment of successive spoke nuts on the wheel rim. Some wheels are noted to have spoke nuts aligned on the centerline of the wheel rim, while others have a staggered, alternating pattern of spoke nuts offset to either side of the rim centerline.
[0028] Although clips 10 are shown on every spoke 22 or on every other spoke 22 in the illustrated examples of FIGS. 4A and 4B , the spacing of clips 10 around the wheel can be varied.
[0029] FIG. 5 shows a bike wheel 20 with a completed array of clips 10 and EL wire 30 . Clips 10 hold the wire securely adjacent the wheel rim 26 on spoke nuts 24 , providing a steady circle of non-flickering, non-motion-dependent illumination when the wire is illuminated. Wire 30 may be powered and controlled by a combined battery power pack and controller unit 40 , for example the commercially available Bikeglow™ kit. Battery pack/controller 40 is secured to the wheel 20 to rotate with the wheel, for example by taping or clipping it to spokes 30 so that it does not protrude beyond the spokes.
[0030] While the entirety of the illuminated wire 30 is preferably lit in a steady fashion all the way around the wheel to prevent distracting flickering at night, it would also be possible to use a flashing light pattern for wire 30 , an option believed to be provided by the Bikeglow™ controller 40 with the press of a button.
[0031] While wire 30 is shown installed around the full circumference of wheel 20 in FIG. 5 , the wire 30 could alternately be installed partway around the wheel with clips 10 .
[0032] While actively-illuminated wire operated by a battery pack is shown in the illustrated example, and is preferred, “illuminated” could include reflective wire.
[0033] It will finally be understood that the disclosed embodiments represent presently preferred examples of how to make and use the invention, but are intended to enable rather than limit the invention. Variations and modifications of the illustrated examples in the foregoing written specification and drawings may be possible without departing from the scope of the invention. It should further be understood that to the extent the term “invention” is used in the written specification, it is not to be construed as a limiting term as to number of claimed or disclosed inventions or discoveries or the scope of any such invention or discovery, but as a term which has long been conveniently and widely used to describe new and useful improvements in science and the useful arts. The scope of the invention supported by the above disclosure should accordingly be construed within the scope of what it teaches and suggests to those skilled in the art, and within the scope of any claims that the above disclosure supports in this application or in any other application claiming priority to this application.
|
A spoke clip adapted to be removably secured to a spoke nut of a bicycle wheel, and further adapted to mount an illuminated wire to the spokes of the bicycle wheel. The clips are generally L- or T-shaped, with a slotted stem having a spoke-admitting initial width and terminating in a spoke nut socket, and a wire-mounting arm perpendicular to the stem and adapted to receive and hold a wire in parallel to the axis of the stem. The invention also includes the illuminated wire display created by securing an illuminated wire in a planar array to the spokes adjacent the wheel rim using a plurality of the spoke clips.
| 8
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Applications No. 60/289,159 filed May 7, 2001 and No. 60/311,472 filed Aug. 10, 2001.
REFERENCE REGARDING FEDERAL SPONSORSHIP
[0002] Not Applicable
REFERENCE TO MICROFICHE APPENDIX
[0003] Not Applicable
[0004] 1. Field of the Invention
[0005] The present invention relates to a device and method for monitoring the flow of liquids and, more particularly, for monitoring the flow of urine in a urinal, such as a waterless urinal, to determine when a trap cartridge needs to be changed or serviced.
[0006] 2. Description of Related Art and Other Considerations
[0007] Waterless urinals, such as are disclosed in U.S. Pat. No. 6,053,197 and U.S. patent application, Ser. No. 09/855,735 (filed May 14, 2001), typically use a water trap in which a low density sealant layer covers a small amount of wastewater remaining in the urinal trap. Such urinals conventionally do not have a flush mechanism; therefore, some amount of wastewater will remain in the trap at all times. The sealant layer prevents odors from escaping from and through the wastewater. Any slow draining of wastewater from the trap or blocking within the trap or sufficient use of the urinal to cause the supply of sealant to be significantly diminished, will result in unpleasant odors. Therefore, it is important for such urinals to be cleaned and serviced regularly, and especially when draining slowly, and a need exists for determining when the conditions for cleaning and servicing pertain.
SUMMARY OF THE INVENTION
[0008] These and other problems are successfully addressed and overcome by the present invention, along with attendant advantages. The present invention employs an electric device, including a PROM and associated algorithm, to monitor urine flow through the cartridge trap. Measuring the duration of such flow and the number of times the urinal is used will determine, in accordance with preset criteria, when servicing or replacement is needed, and alerts a janitor or repairman or other service person by a warning light or other signal. Because urine has a high mineral content, it is electrically conductive, effective to complete circuits between closely spaced metal contacts coupled to the PROM, which allows the manner and existence of the urine to be detected.
[0009] Other aims and advantages, as well as a more complete understanding of the present invention, will appear from the following explanation of an exemplary embodiment and the accompanying drawings thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a perspective view of the present invention depicting a removable trap utilized in a urinal with a liquid flow meter installed therein;
[0011] [0011]FIG. 2 is a cross-sectional view of the present invention illustrated in FIG. 1;
[0012] [0012]FIG. 3 is a perspective view of the liquid flow meter taken from its exterior or cover;
[0013] [0013]FIGS. 4 and 5 are side views of the exterior or cover of the liquid flow meter, with one taken 90° from the other;
[0014] [0014]FIG. 6 is an electric schematic diagram of the of the liquid flow meter;
[0015] [0015]FIG. 7 is an exploded perspective view of the present invention;
[0016] [0016]FIG. 8 is a perspective view of the liquid flow meter depicted in FIG. 3 with its outer cover removed to disclose the interior components thereof;
[0017] [0017]FIG. 9 is a top view of the liquid flow meter;
[0018] [0018]FIG. 10 is a bottom, upwardly looking view of the liquid flow meter, taken 90° from that depicted in FIG. 9;
[0019] [0019]FIGS. 11 and 12 are side views of the liquid flow meter, with one view being taken 90° from the other;
[0020] [0020]FIGS. 13 and 14 are perspective views of the respective negative and positive battery clips used in the liquid flow meter illustrated in FIGS. 7 - 11 ;
[0021] [0021]FIG. 15 is a perspective view of the sensor contact clips employed in the liquid flow meter illustrated in FIGS. 8 - 12 ;
[0022] [0022]FIG. 16 is a logic flow chart depicting the algorithm utilized in operating the liquid flow meter of the present invention; and
[0023] [0023]FIG. 17 is a chart setting forth the variables for programming the computer chip used in the liquid flow meter.
DETAILED DESCRIPTION
[0024] Accordingly, as depicted in FIGS. 1 and 2, an odor trap 20 , such as disclosed in above-mentioned U.S. Pat. No. 6,053,197 and U.S. patent application, Ser. No. 09/855,735, comprises a cylindrical housing 22 , a bottom portion 24 and a cover or top portion 26 , which define an interior 27 . Internally, odor trap 20 includes a vertical baffle 28 secured to and extending downwardly from cover 26 , a sloped, generally horizontal baffle 30 secured to vertical baffle 28 and an overflow riser 32 extending upwardly from bottom portion 24 . Overflow riser 32 comprises a walled section to form a discharge path from interior 27 of trap 20 through an exit 34 which is coupled to an external drain system. An entry 36 forms an opening into interior 27 .
[0025] The interior is adapted to retain a conductive liquid 38 , e.g., wastewater such as a mixture of water and urine, on which a sealant layer 40 of oily substance floats. Accordingly, the wastewater enters odor trap 20 through one or more openings 36 , flows into and passes through sealant layer 40 , and flows atop and beneath baffle 30 on its journey over overflow riser 32 and out of the odor trap through exit 34 .
[0026] Cover 26 is further provided with a centrally positioned opening 42 , surrounded by entry 36 .
[0027] As illustrated generally in FIGS. 3 - 5 and in greater detail in FIGS. 7 - 15 , a liquid flow meter 50 is adapted to be secured to odor trap 20 at cover opening 42 . Specifically, meter 50 is provided with connector 52 comprising a post 54 terminating in a pair of tangs 56 bulbous bosses 58 . Cover opening 42 and post 54 have approximately equal diameters to permit bosses 58 to pressed tangs 56 together as they pass through the cover opening and thence to snap outwardly to latch the liquid flow meter to odor trap 20 .
[0028] The electric circuit embodied in liquid flow meter 50 is shown in FIG. 6. The driving mechanism of the meter is embodied in a microcontroller 60 , such as a 12LC508A-04/SN microcontroller, which is one of a PICD12C5XX family of microcontrollers from Microchip Technology. The PICD12C5XX is defined as a family of low-cost, high performance, 8-bit, fully static, EEPROM/EPROM/ROM based CMOS microcontrollers. It employs a RISC architecture with 33 single word/single cycle instructions. All instructions are single style (1 μs) except for program branches which take two cycles. The PICD12C5XX includes 12-bit wide instructions which are highly symmetrical, resulting in 2:1 code compression.
[0029] Microcontroller 60 is provided with eight input and output pins (numbers 1 - 8 ) in which pins “6” and “7” are coupled to a pair of contact sensor probes 62 and 64 at their respective contact points 62 x and 64 x respectively by leads 62 ′ and 64 ′. Pin “5” is coupled through a resistor 66 to a LED 68 through the intermediary of leads 67 , and pin “1” is coupled to a source of power “VCC” 70 , such as a 3.3 volt lithium battery, e.g., CR1220. The couplings to the positive side of battery 70 is through a connection device having three termini, respectively designated battery clip (positive) 70 and 70 a′, a″, a′″ (see FIGS. 7 - 14 ). The couplings to the negative side of battery 70 is through a connection device having two termini, respectively designated battery clip (negative) 70 and 70 b′, b″ (also see FIGS. 7 - 14 ). These termini act both as clips and as electric connections aided, for example, by soldering. LED 68 is coupled to power source 70 . Pin “8” is grounded, as designated by indicium 76 . Functioning of the microprocessor and its circuit are described below.
[0030] The various connections among the several electric components including microcontroller 60 , sensor probes 62 and 64 , resistor 66 , positive and negative battery clips 70 a and 70 b are enabled by a circuit board 78 . Where needed, insulation is provided, such as by a clip insulator 80 .
[0031] As best shown in FIGS. 2 - 5 , sensor probes 62 and 64 are positioned in liquid flow meter 50 so that their exposed termini 63 do not extend to the bottom surface (designated by indicium 65 ) of the meter and, therefore, are spaced from cover 26 . This spacing of termini 63 avoids undesired closure between the probes, should, for example, the level of the liquids in odor trap 20 rise during use through entry 36 in cover 26 . Further, the spacing between termini 62 c and 64 b and between termini 62 b and 64 c, in particular, is limited to a minimum distance to avoid unintentional contact therebetween, for example, of droplets of wastewater that have not passed through entry 36 .
[0032] Reference is now made to FIGS. 16 and 17. FIG. 16 illustrates the flow of logic used in sensing and measuring the activities occurring in odor trap 20 . The glossary of terms used in the following is:
[0033] “Uses”—A use is when the sensor contacts detect the presence of a fluid, within a specified period of time.
[0034] “Use Counter” or “Counter #1”—Counts the total number of uses
[0035] “Use Timer” or “Timer #1”—A Use Timer determines the period of time between initial fluid contact and when the next fluid contact can be recorded.
[0036] “Blockage”—A blockage is when fluid is detected by the sensor contacts continuously for a specified amount of time.
[0037] “Blockage Timer” or “Timer #2”—Blockage Timer records records the duration of continuous fluid presence by the sensor contacts.
[0038] “Blockage Counter” or “Counter #2”—Blockage Counter records the number of blockages as determined by Blockage Timer, when the timer exceeds a specific minimum amount of time.
[0039] Further, in the following exposition of the algorithm, the term “X” indicates time which is a programmable variable, to which reference is directed to FIG. 17. Operation is assumed that meter 50 is in an inactive “turned-off” condition. Operation commences, as shown in enclosure 100 , when urine flow contacts sensors on indicator or meter to activate the system. As shown in enclosure 102 , counter #1 in microprocessor 60 records one use. Counter #1 will not record another use for “X1” amount of time or if probes 62 and 64 are submerged. If, as depicted in enclosure 104 , the urine maintains contact between the probes for a time longer than an “X3” period of time, counter #2 records one blockage. In the next step, as outlined in enclosure 106 , if blockage occurs “X4” number of times consecutively, LED 68 flashes to indicate a blockage. As shown in enclosure 108 , flashing continues until power is exhausted or reset is activated. However, as pointed out in enclosure 112 , if blockage does not occur for “X4” number of times consecutively, counter #2 resets to 0.
[0040] Alternatively, as stated in enclosure 110 , when the number of uses reaches “X5”, the end of the lifecycle of flashing LED 68 is activated for “X6” of a second and “X7” times a minute, and the program proceeds directly to the step outlined in enclosure 108 , that is, flashing continues until power is exhausted or reset is activated.
[0041] The next step proceeds to that embraced in enclosure 114 , if the reset feature is active in progress, that is, if the sensor contacts are closed “X8” number of times within 4 seconds, the indicator/meter 60 will proceed to a warning state. If the sensor contacts are closed “X8” number of times within 4 seconds again, the indicator will reset. Finally, as circumscribed in enclosure 116 , if reset is activated, all counters are reset to 0.
[0042] Optionally, as set forth in enclosure 118 , LED 68 will single flash for “X2” time per use.
[0043] Several materials may be used in the present invention. The cover shell may be made of any number of thermoplastic materials such as ABS or polypropylene plastic. The electronics are held in place in the mold by the location of the LED and the sensor contact points. Although injection molding is one method of encapsulation, other methods could be used successfully, such as potting and cold injection.
[0044] The present invention is installed by placing the split ball stem (connector 52 , post 54 , post 56 , pair of tangs 56 , bosses 58 ) located at the base of the indicator into mounting hole 42 located in the center of drain holes 36 on the top or cover of the cartridge.
[0045] The present invention operates in three states:
[0046] 1. Packaged: Preinstalled into the lid of the cartridge, the indicator is active but in a sleep mode.
[0047] 2. Installed: Indicator and cartridge is installed in a urinal and ready for first urine contact. No information is stored save for the ROM programming.
[0048] 3. Initial Fluid Detection: The high mineral content of the urine (or water, which has a lesser mineral content) will complete the circuit between the sensor probes, powering the chip and allowing information to be stored.
[0049] In one embodiment, the algorithm of the Fluid Detection state, as noted above, is as follows:
[0050] 1. Upon each detection of fluid, “Use Counter” will increment by (1), and “Use Timer” records Duration of fluid detection. The “Use Counter” will not record another use for a short, predetermined amount of time (e.g., 50 seconds) to avoid falsely recording two uses, when only one use should be recorded or as long as the fluid is still present).
[0051] 2. If number of uses (Use Counter) is greater than the predetermined number (in one embodiment, 7000), the unit activates Change Signal (continuous or flashing LED).
[0052] 3. If the Time Duration of fluid detection is greater than the predetermined value (in one embodiment, 75 seconds), Blockage Counter increments by (1).
[0053] 4. If Blockage Counter equals the predetermined number (in one embodiment, 3) and these events are consecutive, unit activates Change Signal (FLASH).
[0054] 5. If the predetermined number of Blockage Events is not consecutive then the Blockage Counter will reset to zero.
[0055] In an alternative embodiment, a reset feature is provided:
[0056] 1. If time duration of flow is less than one second, very short predetermined value (in one embodiment, 0.5 seconds), clicks the Reset Counter once, and tracks Reset Time.
[0057] 2. If the Reset Counter equals a predetermined value (in one embodiment, 10) and the Reset Time is less than or equal to a predetermined value (in one embodiment, 5 seconds), all counters are reset to zero.
[0058] 3. If Reset Time is greater than a predetermined value (in one embodiment, 5 seconds) resets Reset Counter and Reset Time to zero.
[0059] In a related alternative embodiment, a feature is provided to signal if the urinal is blocked: If time duration of flow is greater than a very long predetermined value (in one embodiment, 75 seconds, for example), the unit activates Change Signal.
[0060] In an alternative embodiment, the present invention will give a Change Signal triggered by a total time in service.
[0061] 1. Upon Initial Fluid Detection, Powers Chip and initiates Duration Clock.
[0062] 2. When Duration Clock reaches a predetermined number of days (in one embodiment, 90 days) activates Change Signal.
[0063] In another alternative embodiment, the present intention will flash an LED every time it is in use:
[0064] 1. Upon Fluid Detection, activates In-Use Flash Signal ({fraction (1/10)} second) to indicate the device is working. In-Use Flash Signal feature resets upon end of Fluid Detection.
[0065] In the another alterative embodiment, the present invention uses a second LED to provide an in-use signal, and the first LED for overfill. The two LED's may employ different colors. Further, different colors and different LED's may be used for different signals.
[0066] The device can be employed in a flush urinal, by connecting it to a solenoid valve that cuts off the flow of flush water in the event of blockage. The connection may be by hard wire or transmitter and receiver.
[0067] Although water has a lower mineral content and will work, a properly adjusted sensor is needed to determine the difference between water and urine. Thus, in an alternative embodiment, the resistance limit is set so that water, which may be used to flush out the system, is not recognized, but urine is.
[0068] Although the invention has been described with respect to a particular embodiment thereof, it should be realized that various changes and modifications may be made therein without departing from the spirit and scope of the invention.
|
A liquid flow meter ( 50 ), including a microcontroller ( 60 ) and associated algorithm, monitors urine flow through a cartridge trap ( 20 ). Measuring the duration of such flow and the number of times the urinal is used will determine, in accordance with preset criteria, when servicing or replacement is needed, and alerts a service person to that effect by a warning light ( 68 ) or other signal. Because urine has a high mineral content, it is electrically conductive, effective to complete circuits between closely spaced metal contacts ( 62 a - 62 c, 64 a - 64 c ) coupled to the PROM, which allows the manner and existence of the urine to be detected. The liquid flow meter is installed in the cartridge trap by utilizing and placing a split ball stem ( 52 ) located at the base of the meter into a mounting hole ( 42 ) located in the center of the drain holes ( 36 ) on the cartridge cover ( 26 ).
| 4
|
PRIORITY INFORMATION
This application claims the benefit of U.S. Provisional Application No. 60/474,486 filed on May 30, 2003.
FIELD OF THE INVENTION
The field of this invention is downhole packers and more particularly those that are set with expansion force and finally those that use a bias to increase diameter independently of the applied expansion force.
BACKGROUND OF THE INVENTION
Annular spaces downhole are typically sealed with packers. Packers can be used in cased or open hole. One type of packer involves an element mounted to a mandrel, where the element is made of an elastomer. The packer is placed downhole and can be set by mechanical compression of the element. The longitudinal mechanical compression increases the diameter. Another technique has been to simply expand the mandrel to increase the outside diameter of the annularly shaped element. One such technique is the Poroflex® product from Halliburton, which uses a solid ribbed elastomer sleeve that is longitudinally compressed by an advancing swage. The driving of the swage also increases the mandrel diameter. The ribbing allows part of the sleeve to collapse on itself in a series of accordion folds. The forming of the folds is claimed to bridge the annular gap around the mandrel. The swage is sized so as not to collapse the accordion folds of the collapsed elastomer sleeve. This product is advertised for cased hole applications and appears unsuitable for open hole applications. It also has some uncertainties as to how well it will seal. Longitudinal compression will not always assure that the sleeve will collapse uniformly over the ribbed length. The sealing occurs by end contact of each accordion fold with the casing wall. The number of such ends in contact with the casing wall due to collapse and expansion is uncertain. The possibility, even in cased hole, exists for channeling between the fold ends and the casing wall. The element is not pre-stretched to reduce its run in diameter and therefore can get thinner after swaging to the point where the sealing integrity may be in question. Accordingly, a design is needed that can better address the above described sealing problems in cased hole and that has the ability to seal effectively in open hole.
The present invention employs an annular sleeve as the sealing element and mounts a biasing element with it. The biasing element stores a force, which is liberated downhole to longitudinally compress the element and increase its diameter. In a preferred embodiment the advancing swage liberates a stored force to allow the element diameter to grow to its relaxed dimension. Preferably, the advancing swage liberates this force and increases the mandrel dimension when the element is already at its relaxed diameter forcing the element into the borehole wall or the casing. How this is accomplished, so that those skilled in the art will readily appreciate the scope of the invention, will be explained more fully in the detailed description of the preferred embodiment and the claims, which appear below.
Relevant to the general area of sealing devices, with some illustrating downhole applications are U.S. Pat. Nos. 2,449,514; 4,545,433; 5,062,482; 6,543,780 B1 and Re. 32,831.
SUMMARY OF THE INVENTION
A packer element has a biasing member incorporated with it. The element is either fabricated with the biasing element in a relaxed condition and then the element is stretched prior to insertion downhole or the element is created around the stressed biasing member and is held in that position until allowed to relax downhole. In either event the release of the element increases its diameter while shortening its length. Preferably, an advancing swage triggers the release to allow the element to expand as much as it can go or to the maximum relaxed diameter, whichever is larger. The swage then, preferably, drives the relaxed element toward the borehole wall or the casing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a run in cross-section of a coiled spring embodiment shown in an open hole application;
FIG. 2 is the view of FIG. 1 showing the coiled spring allowed to relax to expand the diameter of the element;
FIG. 3 is the view of FIG. 2 showing the swage advanced to expand the mandrel under the already diametrally enlarged element;
FIG. 4 is an alternate embodiment to FIG. 1 using a leaf spring and shown in the run in position;
FIG. 5 is the view of FIG. 4 in the spring-relaxed position where the diameter of the element has enlarged;
FIG. 6 is the view of FIG. 5 after expansion of the mandrel with a swage;
FIG. 7 is an alternative to FIG. 1 without any biasing and where the element is stretched to reduce its run-in diameter;
FIG. 8 is the view of FIG. 7 with the element in a relaxed position;
FIG. 9 is the view of FIG. 8 after the mandrel is swaged;
FIG. 10 is a detailed view of the latch at run in;
FIG. 11 is the view of FIG. 10 with expansion releasing the latch to allow the element to shrink in length and expand in diameter;
FIGS. 12–16 are a sequential view showing how the advancing swage releases the latch and passes through to finish the expansion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a mandrel 10 with an element 12 that has a biasing element 14 , which, in this Figure happens to be a coiled spring. Those skilled in the art will recognize that other types of biasing elements are contemplated, such as: leaf springs (see FIGS. 4–6 ), Belleville washers or even no biasing element at all (see FIGS. 7–9 ). The advantage of pre-stretching is that the initial outside diameter is reduced. For example, in a monobore application, the mandrel 10 and the element 12 must fit through the casing 16 and after expansion in open hole 18 , assume an inside diameter 20 (see FIG. 3 ) approximating that of the casing 16 . Without pre-stretching to reduce the outside diameter of the element 12 the element thickness has to be reduced for a given mandrel diameter. Later when expansion takes place in open hole, the element may not make sealing contact with the borehole wall 18 .
The present invention, as shown in FIG. 1 , involves building a relaxed spring into the un-stretched element 12 and then stretching the assembly and holding it in that position for run in. Preferably, retainer 22 is fixed to mandrel 10 while retainer 24 is temporarily secured by a latch or another equivalent device shown schematically as 26 . Advancing the swage 28 releases the latch 26 and allows the element 12 to shorten in length and to grow in diameter, aided by the stored force in spring 14 . Spring 14 wants to get shorter when latch 26 is tripped. Now, as shown in FIG. 2 element 12 has shrunk in length and grown in diameter so that its outside diameter is substantially larger than during the run in. Now, when the swage 28 advances under the element 12 there is a better assurance that the element 12 will seal against the borehole wall 18 . Those skilled in the art will appreciate that the illustrated embodiments of the device can be used in cased as well as in open hole.
An alternative way to make the device in FIG. 1 is to build an element 12 over an extended spring 14 and hold the element against shrinkage until it is delivered through casing 16 . When the swage 28 is advanced and latch 26 is released, the spring 14 can relax and shorten the element 12 to make its diameter increase before the swage 28 expands the mandrel 10 under the element 12 .
The spring 14 may be bonded to element 12 , which is preferably a cured elastomer. The boding may be total or partial. Alternatively, there may be no bonding at all. The spring 14 can be totally imbedded in the element 12 or it may be partially embedded or mounted externally in a manner that its relaxation will reduce the length and increase the diameter of the element 12 .
FIGS. 4–6 operate identically to FIGS. 1–3 and may be manufactured in the two ways described above for FIGS. 1–3 . Again, the casing is 16 ′. The difference is that the spring is a leaf spring 30 that collapses on itself when latch 26 ′ is released. Those skilled in the art will appreciate that the leaf spring 30 may be composed of segments that are independent or tied together or a solid ring. Similarly, spring 14 can be one or more springs which could be stacked or nested. Each coil spring can have a constant or variable diameter or a constant or a plurality of pitches. The wire diameter can vary, as can the materials of construction even within a single spring. If Belleville washers are used, they can be stacked in one direction or stacked in more than one direction and can incorporate material and dimensional variations to obtain the desired performance.
Ideally, after the element 12 or 12 ′ has attained its relaxed large diameter shown in FIGS. 2 and 5 , the expansion of mandrel 10 or 10 ′ will ensure that there is tight sealing contact with the borehole wall. Since expansion of mandrel 10 can further reduce its length, there is an added force created on the element 12 tending to longitudinally compress it. The element 12 makes contact with the borehole 18 over a substantial portion of its length, as compared with the contact of the accordion folded ends of the Halliburton product.
FIGS. 7–9 illustrate the same element 12 ″ that now is without any associated biasing structure. It is simply initially stretched to reduce its outer dimension for run in. Advancing the swage 28 ″ will allow it to shrink in length and expand in diameter. The mandrel 10 ″ can then be expanded to get the element 12 ″ up against the borehole wall 18 ″. Here again, expansion of the mandrel past retainer 24 ″ will result in a further compression of element 12 ″ that is trapped between retainer 24 ″, now fixed to mandrel 10 ″ due to expansion and retainer 22 ″ that was initially connected to mandrel 10 ″. This is because diametral expansion results in a shortening of length of the mandrel 10 ″. Alternatively, the swage 28 ″ can actually drive the retainer 24 ″ along mandrel 10 ″ so that the element 12 ″ is compressed against retainer 22 ″.
FIGS. 10 and 11 show respectively, the latch mechanism 26 which is preferably a ring 32 that shears on movement of the swage 28 to allow the element 12 to shrink, shown in the run in and released position. Other devices that release on mandrel expansion are within the scope of the invention. FIG. 10 shows ring 24 having a hook 40 that is retained by ring 32 . Ring 32 can be assembled in pieces that are held to each other by a breakable member 42 . Ring 32 is held from moving longitudinally by retaining rings 44 and 46 that are mounted on either side of it. Rings 44 and 46 can be overlapping open rings that simply grow in diameter when the swage 28 , see FIG. 11 , breaks the breakable member 42 to release the hook 40 to allow the spring 14 , if used, to draw up ring 24 while the element 12 shrinks in length and grows in diameter. FIGS. 12–16 show in sequence the latch release procedure just described as seen from a larger perspective. In FIGS. 12 and 13 , the swage 28 approaches the latch mechanism 26 . In FIG. 14 the latch mechanism 26 is released. FIG. 15 shows that on further advance of the swage 28 , the latch mechanism 26 has shifted because the mandrel 10 has shrunk in length due to the expansion. FIG. 16 shows the swage 28 passing under the element 12 , which is now pressed firmly against the casing wall 18 .
Those skilled in the art will appreciate that the present invention reduces the element thickness by stretching it. It can then pass through casing into open hole and be released. If a biasing member is used, it will aid in the longitudinal shrinking and the radial expanding of the element. The swage can be the trigger for the release of the element and ultimately the device that expands the mandrel to force the already relaxed and larger in diameter element against the borehole wall.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention.
|
A packer element has a biasing member incorporated with it. The element is either fabricated with the biasing element in a relaxed condition and then the element is stretched prior to insertion downhole or the element is created around the stressed biasing member and is held in that position until allowed to relax downhole. In either event the release of the element increases its diameter while shortening its length. Preferably, an advancing swage triggers the release to allow the element to expand as much as it can go or to the maximum relaxed diameter, whichever is larger. The swage then, preferably, drives the relaxed element toward the borehole wall or the casing.
| 4
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This applications of U.S. patent application Ser. No. 09/461,485, filed Dec. 14, 1999 now abandoned; which is a divisional of U.S. patent application Ser. No. 09/237,999, filed Jan. 26, 1999 now abandoned, which claims the benefit of U.S. Provisional Application Nos. 60/072,484, 60/072,487, 60/072,483 and 60/072,482, all filed Jan. 26, 1998.
THE TECHNICAL FIELD
The present invention relates generally to mitochondria protecting agents for treating diseases in which mitochondrial dysfunction leads to tissue degeneration and, more specifically, to compounds, compositions and methods for treating such diseases.
BACKGROUND OF THE INVENTION
Mitochondria are the subcellular organelles that manufacture essential adenosine triphosphate (ATP) by oxidative phosphorylation. A number of degenerative diseases may be caused by or associated with either direct or indirect alterations in mitochondrial function. These include Alzheimer's Disease, diabetes mellitus, Parkinson's Disease, neuronal and cardiac ischemia, Huntington's disease and other related polyglutamine diseases (spinalbulbar muscular atrophy, Machado-Joseph disease (SCA-3), dentatorubro-pallidoluysian atrophy (DRPLA) and spinocerebellar ataxias 1, 2 and 6), dystonia. Leber's hereditary optic neuropathy, schizophrenia, and myodegenerative disorders such as “mitochondrial encephalopathy, lactic acidosis, and stroke” (MELAS), and “myoclonic epilepsy ragged red fiber syndrome” (MERRF).
Defective mitochondrial activity, including but not limited to failure at any step of the elaborate multi-complex mitochondrial assembly, known as the electron transport chain (ETC), may result in 1) decreases in ATP production, 2) increases in the generation of highly reactive free radicals (e.g., superoxide, peroxynitrite and hydroxyl radicals, and hydrogen peroxide). 3) disturbances in intracellular calcium homeostasis and/or 4) release of apoptosis inducing factors such as, e.g., cytochrome c. Because of these biochemical changes, mitochondrial dysfunction has the potential to cause widespread damage to cells and tissues For example, oxygen free radical induced lipid peroxidation is a well established pathogenetic mechanism in central nervous system (CNS) injury such as that found in a number of degenerative diseases, and in ischemia (i.e., stroke).
Mitochondrial dysfunction also is thought to be critical in the cascade of events leading to apoptosis in various cell types (Kroemer et al., FASEB J . 9:1277-87, 1995). Altered mitochondrial physiology may be among the earliest events in apoptosis (Zamzami et al., J. Exp. Med . 182:367-77, 1995; Zamzami et al., J. Exp. Med . 181:1661-72, 1995. In several cell types, including neurons, reduction in the mitochondrial membrane potential (Δψm), a sign of mitochondrial dysfunction, precedes the nuclear DNA degradation that accompanies apoptosis. In cell-free systems, mitochondrial, but not nuclear, enriched fractions are capable of inducing nuclear apoptosis (Newmeyer et al., Cell 70:353-64, 1994). Perturbation of mitochondrial respiratory activity leading to altered cellular metabolic states may occur in mitochondria associated diseases and may further induce pathogenetic events via apoptotic mechanisms. For example, altered mitochondrial activity may lead to undesirable elevated levels of intracellular reactive oxygen species (ROS) and subsequent intracellular damage or cell death.
Stressed (e.g., stressors included free radicals, high intracellular calcium. loss of ATP, among others) mitochondria may release preformed soluble factors that can initiate apoptosis through an interaction with novel apoptosomes (Marchetti et al., Cancer Res . 56:2033-38, 1996; Li et al., Cell 91:479-89, 1997). Release of preformed soluble factors by stressed mitochondria, like cytochrome c, may occur as a consequence of a number events. In some cases, release of apoptotic molecules (apoptoqens) occurs when mitochondria undergo a sudden change in permeability to cytosolic solutes under 1.5 KDa. This process has been termed permeability “transition”. In other cases, the permeability may be more subtle and perhaps more localized to restricted regions of a mitochondrion. In still other cases, overt permeability transition may not occur but apoptogens can still be released as a consequence of mitochondrial abnormalities. Thus, changes in mitochondrial physiology may be important mediators of apoptosis. To the extent that apoptotic cell death is a prominent feature of degenerative diseases, mitochondrial dysfunction may be a critical factor in disease progression.
Diabetes mellitus is a common, degenerative disease affecting 5 to 10 percent of the population in developed countries. The propensity for developing diabetes mellitus is reportedly maternally inherited, suggesting a mitochondrial genetic involvement (Alcolado et al., Br. Med. J . 302:1178-1180, 1991; Reny, International J. Epidem . 23:886-890, 1994). Diabetes is a heterogeneous disorder with a strong genetic component; monozygotic twins are highly concordant and there is a high incidence of the disease among first degree relatives of affected individuals.
At the cellular level the degenerative phenotype that may be characteristic of late onset diabetes mellitus includes indicators of altered mitochondrial respiratory function for example impaired insulin secretion and responsivity decreased ATP synthesis and increased levels of reactive oxygen species. Studies have shown that diabetes mellitus may be preceded by or associated with certain related disorders. For example, it is estimated that tort million individuals in the U.S. suffer from late onset impaired glucose tolerance (IGT). IGT patients fail to respond to glucose with increased insulin secretion. A small percentage (5-10%) of IGT individuals progress to insulin deficient non-insulin dependent diabetes (NIDDM) each year. Some of these individuals further progress to insulin dependent diabetes mellitus (IDDM). These forms of diabetes mellitus. NIDDM and IDDM, are associated with decreased release of insulin by pancreatic beta cells and/or a decreased end-organ response to insulin. Other symptoms of diabetes mellitus and conditions that precede or are associated with diabetes mellitus include obesity, vascular pathologies, peripheral and sensory neuropathies, blindness and deafness.
Due to the strong genetic component of diabetes mellitus, the nuclear genome has been the main focus of the search for causative genetic mutations. However, despite intense effort, nuclear genes that segregate with diabetes mellitus are known only for rare mutations in the insulin gene, the insulin receptor gene, the adenosine deaminase gene and the glucokinase gene. Accordingly, mitochondrial defects, which may include but need not be limited to defects related to the discrete non-nuclear mitochondrial genome that resides in mitochondrial DNA, may contribute significantly to the pathogenesis of diabetes mellitus.
Parkinson's disease (PD) is a progressive, mitochondria associated neurodegenerative disorder characterized by the loss and/or atrophy of dopamine-containing neurons in the pars compacta of the substantia nigra of the brain. Like Alzheimer's Disease (AD), PD also afflicts the elderly. It is characterized by bradykinesia (slow movement), rigidity and a resting tremor. Although L-Dopa treatment reduces tremors in most patients for a while, ultimately the tremors become more and more uncontrollable, making it difficult or impossible for patients to even feed themselves or meet their own basic hygiene needs.
It has been shown that the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces parkinsonism in animals and man, at least in part through its effects on mitochondria. MPTP is converted to its active metabolite, MPP − , in dopamine neurons; it then becomes concentrated in the mitochondria. The MPP then selectively inhibits the mitochondrial enzyme NADH:ubiquinone oxidoreductase (“Complex I”), leading to the increased production of free radicals, reduced production of adenosine triphosphate and. ultimately the death of affected dopamine neurons.
Mitochondrial Complex I is composed of 40-50 subunits, most are encoded by the nuclear genome and seven by the mitochondrial genome. Since parkinsonism may be induced by exposure to mitochondrial toxins that affect Complex I activity, it appears likely that defects in Complex I proteins may contribute to the pathogenesis of PD by causing a similar biochemical deficiency in Complex I activity. Indeed, defects in mitochondrial Complex I activity have been reported in the blood and brain of PD patients (Parker et al., Am. J. Neurol . 26:719-723, 1989).
Similar theories have been advanced for analogous relationships between mitochondrial defects and other neurological diseases, including Alzheimer's disease (AD), Leber's hereditary optic neuropathy, schizophrenia, “mitochondrial encephalopathy, lactic acidosis and stroke” (MELAS), and “myoclonic epilepsy ragged red fiber syndrome” (MERRF).
For example, AD is a progressive neurodegenerative disorder that is characterized by loss and/or atrophy of neurons in discrete regions of the brain, and that is accompanied by extracellular deposits of β-amyloid and the intracellular accumulation of neurofibrillary tangles. It is a uniquely human disease, affecting over 13 million people worldwide. It is also a uniquely tragic disease. Many individuals who have lived normal, productive lives are slowly stricken with AD as they grow older, and the disease gradually robs them of their memory and other mental faculties. Eventually, they cease to recognize family and loved ones, and they often require continuous care until their eventual death.
There is evidence that defects in oxidative phosphorylation within the mitochondria are at least a partial cause of sporadic AD. The enzyme cytochrome c oxidase (COX), which makes up part of the mitochondrial electron transport chain (ETC), is present in normal amounts in AD patients; however, the catalytic activity of this enzyme in AD patients and in the brains of AD patients at autopsy has been found to be abnormally low (Parker et al., Neurology 44:1086-1090, 1994). This suggests that the COX in AD patients is defective, leading to decreased catalytic activity that in some fashion causes or contributes to the symptoms that are characteristic of AD.
One hallmark pathology of AD is the death of selected neuronal populations in discrete regions of the brain. Cell death in AD is presumed to be apoptotic because signs of cell death are observed whereas indicators of active gliosis and necrosis are not (Smale et al., Exp. Neiurolog . 133:225-230, 1995; Cotman et al., Molec. Neurobiol . 10:19-45, 1995). The consequences of cell death in AD, neuronal and synaptic loss, are closely associated with the clinical diagnosis of AD and are highly correlated with the degree of dementia in AD (DeKosky et al., Ann. Neurology 27:457-464, 1990).
Indeed. focal defects in energy metabolism in the mitochondria, with accompanying increases in oxidative stress, may be associated with AD. It is well-established that energy metabolism is impaired in AD brain (Palmer et al., Brain Res . 645:338-42, 1994: Pappolla et al., Am. J. Pathol . 140:621-28, 1992; Jeandel et al., Gerontol . 35:275, 1989: Balazs et al., Neurochem. Res . 19:1131-37, 1994; Mecocci et al., Ann Neurol , 36:747-751, 1994; Gsell et al., J. Neurochem . 64:1216-23, 1995). For example, regionally specific deficits in energy metabolism in AD brains have been reported in a number of positron emission tomography studies (Kuhl, et al., J. Cereb. Blood Flow Metab . 7:S406, 1987; Grady, et al., J. Clin. Exp. Neuropsychol . 10:576-96, 1988; Haxby et al., Arch Neurol . 47:753-60, 1990; Azari et al., J. Cereb. Blood Flow Metab . 13:438-47, 1993). Metabolic defects in the temporoparietal neocortex of AD patients apparently presage cognitive decline by several years. Skin fibroblasts from AD patients display decreased glucose utilization and increased oxidation of glucose, leading to the formation of glycosylation end products (Yan et al., Proc. Nat. Acad. Sci. USA 91:7787-91, 1994). Cortical tissue from postmortem AD brain shows decreased activity of the mitochondrial enzymes pyruvate dehydrogenase (Sheu et al., Ann. Neurol 17:444-49, 1985) and α-ketoglutarate dehydrogenase (Mastrogiacomo et al., J. Neurochem . 6:2007-14, 1994), which are both key enzymes in energy metabolism. Functional magnetic resonance spectroscopy studies have shown increased levels of inorganic phosphate relative to phosphocreatine in AD brain, suggesting an accumulation of precursors that arises from decreased ATP production by mitochondria (Pettegrew et al., Neurobiol Of Aging 15:117-32, 1994; Pettigrew et al., Neurobiol. Of Aging 16:973-75, 1995).
Signs of oxidative injury also are prominent features of AD pathology, and reactive oxygen species (ROS) are critical mediators of neuronal degeneration. Indeed, studies at autopsy show that markers of protein, DNA and lipid peroxidation are increased in AD brain probably as a result of increased ROS production secondary to mitochondrial dysfunction (Palmer et al., Brain Res . 645:338-42, 1994; Pappolla et al., Am. J. Pathol . 140:621-28, 1992; Jeandel et al., Gerontol . 35:275-82, 1989; Balazs et al., Arch. Neurol . 4:864, 1994; Mecocci et al., Ann. Neurol . 36:747-51, 1994; Smith et al., Proc. Nat. Acad Sci. USA 88:10540-43, 1991). In hippocampal tissue from AD but not from controls, carbonyl formation indicative of protein oxidation is increased in neuronal cytoplasm, and nuclei of neurons and glia (Smith et al., Nature 382:120-21, 1996). Neurofibrillary tangles also appear to be prominent sites of protein oxidation (Schweers et al., Proc. Nat. Acad. Sci. USA 92:8463, 1995: Blass et al., Arch. Neurol . 4:864, 1990). Under stressed and non-stressed conditions incubation of cortical tissue from AD brains taken at autopsy demonstrate increased free radical production relative to non-AD controls. In addition, the activities increased of critical antioxidant enzymes, particularly catalase, are reduced in AD (Gsell et al., J. Neurochem . 64:121623, 1995), suggesting that the AD brain is vulnerable to increased ROS production. Thus, oxidative stress may contribute significantly to the pathology of mitochondria associated diseases such as AD, where mitochondrial dysfunction and/or elevated ROS may be present.
Accordingly, there is a need for compounds, compositions and methods that limit or prevent damage to organelles, cells and tissues initiated by various consequences of mitochondrial dysfunction. In particular, because mitochondria are essential organelles for producing metabolic energy, agents that inhibit the production of, and/or protect mitochondria and cells against, ROS and other sources of injury would be especially useful. Such agents would be suitable for the treatment of degenerative diseases, including mitochondria associated diseases. The present invention fulfills these needs and provides other related advantages.
SUMMARY OF THE INVENTION
Briefly stated. the present invention is directed to the treatment of mitochondria associated diseases by administration to a warm-blooded animal in need thereof an effective amount of a mitochondria protecting agent having one of the following general structures (I) through (IV):
wherein X 1 , X 2 , X 3 , X 4 , Y 1 , Y 2 , Y 3 , Y 4 , Z 1 , Z 2 , Z 3 , W 1 , W 2 , W 3 , A 1 , R 1 , R 2 , R 3 and R 4 are as identified in the following detailed description.
The compounds of this invention have activity over a wide range of mitochondria associated diseases, including (but not limited to) Alzheimer's Disease, diabetes mellitus. Parkinson's Disease, neuronal and cardiac ischemia. Huntington's disease and other related polyglutamine diseases (spinalbulbar muscular atrophy, Machado-Joseph disease (SCA-3), dentatorubro-pallidoluysian atrophy (DRPLA) and spinocerebellar ataxias 1, 2 and 6), dystonia Leber's hereditary optic neuropathy, schizophrenia, and myodegenerative disorders such as “mitochondrial encephalopathy, lactic acidosis, and stroke” (MELAS), and “myoclonic epilepsy ragged red fiber syndrome” (MERRF).
Accordingly, this invention is also directed to method of treating a mitochondria associated disease by administration of an pharmaceutically effective mount of a mitochondria protecting agent to a warm-blooded animal in need thereof as well as to pharmaceutical compositions containing a mitochondria protecting agent of this invention in combination with a pharmaceutically acceptable carrier or diluent.
These and other aspects of the present invention will become evident upon reference to the following detailed description and attached drawings. To that end, various references are set forth herein which describe in more detail certain aspects of this invention, and are each incorporated by reference in their entirety.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is generally directed to compounds (also referred herein as “mitochondria protecting agents”) and to pharmaceutical compositions containing the same, as well as to methods useful for treating mitochondria associated diseases. More specifically, the mitochondria protecting agents of this invention have an IC 50 ≦50 μm, typically≦1 μm preferably≦200 nM, and more preferably≦70 nM in the dichlorofluorescin diacetate (DCFC) assay described herein, and have one of the following structures (I) through (IV):
including steroisomers and pharmaceutically acceptable salts thereof,
where in structure (I):
X 1 is selected from —OH, —OR a and —OCOCH 3 ;
Y 1 is selected from —OH, —R a OH, —OCOCH 3 and C 1-12 alkyl;
Z 1 is selected from —H, —NHH 2 , —OH, —NO 2 , —OCOCH 3 and C 1-12 alkyl; and
each occurrence of R a is selected from C 1-6 alkyl;
where in structure (II):
R 1 and R 2 are independently selected from —H, —C(═O)C 1-3 alkyl and C 1-3 alkyl;
X 2 is optionally present and selected from —(A 2 )(A 3 )—, —(CH 2 ) n —, —O— and —NH—;
Y 2 and Z 2 are independently selected from —H, —OH, —NH 2 , —NO 2 , —OR b , —NHCNHNH 2 , —NHR b and —NR b R c ;
A 2 and A 3 are independently selected from —H and C 1-3 alkyl;
R b and R c are independently C 1-4 alkyl; and
n is 2-9;
where in structure (III):
the dotted line represents a single or double bond;
A 1 is selected from —H and C 1-3 alkyl;
Y 3 is selected from —H, C 1-3 alkyl and —COR d ;
Z 3 is selected from —H, C 1-3 alkyl and —(CH,) m X 3 R d ;
X 3 is selected at each occurrence from —S—, —O— and —NH—;
R 3 is selected from —H, —CH 3 , —CH 2 CH 3 and —R d ;
R d is selected from a guanidino moiety, a cylcoguanidino moiety, and a non-steroidal anti-inflammatory drug; and
m is 1-4; and
where in structure (IV):
W 1 , W 2 and W 3 are independently selected from —H and C 1-3 alkyl;
X 4 is optionally selected from —NH—, —O— and —S—;
Y 4 is selected from —H and C 1-12 alkyl; and
R 4 is selected from —H, a guanidino moiety, a cylcoguanidino moiety, and a non-steroidal anti-inflammatory drug, or X 4 —R 4 taken together is selected from —CH 2 OH, —OC(═O)CH 3 , and C 1-3 alkyl.
As used herein, the following terms have the meanings set forth below:
A “C 1-12 alkyl” is a straight chain or branched, saturated or unsaturated hydrocarbon moiety having from 1 to 12 carbon atoms, such as methyl, ethyl, propyl, isopropyl butyl, isobutyl, tert-butyl and the like, pentyl, the pentyl isomers, hexyl and the hexyl isomers and the higher homologues having up to 12 carbon atoms such as, for example, heptyl, octyl, nonyl, decyl, undecyl, dodecyl and the like. In instances where a hydrocarbon having a different number of carbon atoms is recited, such as “C 1-3 alkyl”, “C 1-4 alkyl”, “C 1-6 alkyl”, “C 1-8 alkyl” and the like, a straight chain or branched, saturated or unsaturated hydrocarbon moiety is intended, but having the number of carbon atoms indicated.
A “guanidino moiety” and a “cycloguanidino moiety” have the following structure (a) and structure (b), respectively:
wherein R 5 and R6 are independently selected from —H and C,alkyl, and q is 0-3.
A “non-steroidal antiinflammatory drug” (NSAID) is a NSAID having a carboxylic moiety. A number of chemical classes of NSAID have been identified. The following text, the entire contents of which are hereby incorporated by reference in the present specification, may be referred to for various NSAID chemical classes: CRC Handbook of Eicosanoids: Prostaglandins, and Related Lipids, Volume II, Drugs Acting Via the Eicosanoids , pages 59-133, CRC Press, Boca Raton, Fla. (1989). The NSAID may be selected, therefore, from a variety of chemical classes including, but not limited to, salicylic acid or its derivatives including acetylsalicylic acid, fenamic acids, such as flufenamic acid, nitlumic acid and mefenamic acid; indoles, such as indomethacin, sulindac and tolmetin; phenylalkanoic acids, such as suprofen, ketorolac, flurbiprofen and ibuprofen; and phenylacetic acids, such as dictofenac. Further examples of NSAID include loxoprofen, pirprofen, naproxen, benoxaprofen, aceloferac, fleclozic acid, bromfenac, alcofenac, diflunisal, tolfenamic acid. clidanac, fenclorac, carprofen, fenbufen, amfenac, ketoprofen, orpanoxin, pranoprofen, indoprofen, fenoprofen, meclofenamate, isofezolac, etodolic acid, efenamic acid, fenclofenac, zomopirac, zaltoprofen and other NSAID compounds. The preferred compounds are those wherein the NSAID is selected from the ester or amide derivatives of salicylic acid or its derivatives including acetylsalicylic acid, naproxen, ibuprofen or acetylsalicic acid.
In one aspect, the mitochondria protecting agents of this invention have the following structure (I):
including steroisomers and pharmaceutically acceptable salts thereof, wherein
X 1 is selected from —OH, —OR a and —OCOCH 3 ;
Y 1 is selected from —OH, —R a OH, —OCOCH 3 and C 1-12 alkyl;
Z 1 is selected from —H, —NH 2 , —OH, —NO 2 , —OCOCH 3 and C 1-12 alkyl; and
each occurrence of R a is selected from C 1-6 alkyl.
For purpose of clarity, position of Z 1 will be referenced by the following numbering:
In one embodiment of structure (I), X 1 is —OH, Z 1 is —NH 2 , and the compounds of this invention have the following structure (I-1):
Thus, location of the Z 1 substituent in structure (I-1) is referred to herein as a “1—NH 2 ”.
In one embodiment of structure (I-1), Y 1 is C 1-12 alkyl, such as the following structures (I-2) or (I-3):
In another embodiment of structure (I), X 1 and Z 1 are —OH, and the compounds of this invention have the following structure (I-4):
In one embodiment of structure (I-4), Y 1 is C 1-12 alkyl, such as the following structures (I-5) or (I-6);
In still another embodiment of structure (I), X 1 and Z 1 are —OCOCH 3 , and the compounds of this invention have the following structure (I-7):
In one embodiment of structure (I-7), Y 1 is C 1-12 alkyl, such as the following structure (I-8):
In yet another embodiment of structure (I), X 1 and Y 1 are —OH, and the compounds of this invention have the following structure (I-9):
In one embodiment of structure (I-9), Z 1 is C 1-12 alkyl, such as the following structure (I-10):
Representative compounds of structure (I) are set forth in the following Table 1.
TABLE 1
Representative Compounds of Structure (I)
Compound
X 1
Z 1
Y 1
MW
(I-2)
OH
1-NH 2
n-octyl
221
(I-3)
OH
1-NH 2
tert-octyl*
221
(I-5)
OH
1-OH
(CH 2 ) 2 CH 2 OH
168
(I-6)
OH
1-OH
n-propyl
152
(I-8)
OCOCH 3
1-OCOCH 3
n-propyl
236
(I-10)
OH
1-n-propyl
OH
152
(I-11)
OCOCH 3
1-n-propyl
OCOCH 3
236
(I-12)
OH
2-OH
2-propenyl
150
(I-13)
OH
2-propenyl
OH
150
(I-14)
OCH 3
1-NH 2
n-octyl
235
(I-15)
OCH 3
1-NO 2
n-octyl
265
(I-16)
OH
1-NO 2
n-octyl
251
(I-17)
OH
1-NO 2
tert-octyl
235
(I-18)
OCOCH 3
1-NO 2
n-octyl
293
Compound
1 H NMR δ (500 MHz, CDCl 3 )
(I-2)
6.64 (d, 2H), 6.48 (dd, 1H), 2.45 (t, 2H), 1.53 (t, 2H), 1.27 (m, 10H),
0.87 (t, 3H)
(I-3)
6.76 (s, 1H), 6.66 (m, 2H), 1.66 (s, 2H), 1.30 (s, 6H), 0.73 (s, 9H)
(I-5)
6.64 (m, 2H), 6.51 (m, 1H), 3.54 (t, 2H), 2.51 (t, 2H), 1.76 (m, 2H) (in
CD 3 OD)
(I-6)
6.75 (d, 1H), 6.69 (d, 1H), 6.61 (dd, 1H), 2.47 (t, 2H), 1.57 (m, 2H),
0.91 (t, 3H)
(I-8)
7.05 (m, 2H), 7.0 (d, 1H), 2.57 (t, 2H), 2.28 (s, 3H), 2.27 (s, 3H), 1.62
(m, 2H), 0.94 (T, 3H)
(I-10)
6.71 (m, 3H), 5.15 (s, 1H), 5.12 (s, 1H), 2.59 (t, 2H), 1.64 (m, 2H),
0.97(t, 3H)
(I-11)
7.20-7.03 (m, 3H), 2.50 (t, 2H), 2.32 (s, 3H), 2.27 (s, 3H), 1.61 (m,
2H), 0.95 (t, 3H)
(I-14)
7.66 (m, 1H), 7.35-7.33 (m, 1H), 6.99 (d, 1H), 3.93 (s, 3H), 2.59 (t,
2H), 1.61-1.56 (m, 2H), 1.30-1.26 (m, 10H), 0.88 (t, 3H)
(I-15)
6.70 (d, 1H), 6.56-6.52 (m, 2H), 3.82 (s, 3H), 2.46 (t, 2H), 1.58-1.52
(m, 2H), 1.29-1.26 (m, 10H), 0.87 (t, 3H)
(I-16)
10.46 (s, 1H), 7.89 (d, 1H), 7.40 (dd, 1H), 7.07 (d, 1H), 2.59 (t, 2H),
1.60 (m, 2H), 1.32-1.23 (m, 10H), 0.88 (t, 3H)
*tert-octyl = C(CH 3 ) 2 CH 2 C(CH 3 ) 2 CH 3
The compounds of structure (I) may be made by know organic reaction techniques, including those set forth in Example 6 below. For example. as depicted below under reaction “a”, representative alkyl analogues at position Y 1 may be synthesized from the corresponding allyl as the starting material (such as eugenol for n-propyl) and involve hydrogenation of the allyl bond, followed by deprotection of the methyl ether using boron tribromide. Alternatively, as depicted by reaction “b”, the corresponding alkyl-phenol analogue may be employed as the starting material. followed by addition of the desired Z 1 substituent. For example, alkyl phenol derivatives may be made by nitration using nitric acid, optionally followed by reduction with activated iron. In yet a further variation, the alkyl Z 1 substituents can be introduced via Friedel Crafts alkylation of alkyl phenols via reaction “b”. Similarly, hydroxyalkylation of alkyl phenols can be achieved via treatment with an aldehyde and boron containing reagents, such as benzeneboronic acid.
In addition, it should be recognized that the starting materials for the synthesis of compounds of structure (I) are commercially available from a number of sources.
In another aspect, the mitochondria protecting agents of this invention have the following structure (II):
including steroisomers and pharmaceutically acceptable salts thereof, wherein
R 1 and R 2 are independently selected from —H, —C(═O)C 1-3 alkyl and C 1-3 alkyl;
X 2 is optionally present and selected from —C(A 2 )(A 3 )—, —(CH 2 ) n —, —O— and —NH—;
Y 2 and Z 2 are independently selected from —H, —OH, —NH 2 , —NO 2 , —OR b , —NHCNHNH 2 , —NHR b and —NR b R c ;
A 2 and A 3 are independently selected from —H and C 1-3 alkyl;
R b and R c are independently C 1-4 alkyl and
n is 2-9.
For purpose of clarity, position of Y 2 and Z 1 will be referenced by the following numbering:
In one embodiment of structure (II), R 1 and R 2 are —H, Y 2 and Z 2 are —NH 2 , and the compounds of this invention has the following structure (II-1):
In one embodiment of structure (II1), X 2 is —C(A 2 )(A 3 )—, such as the following structure (II-2):
In another embodiment of structure (II), R 1 and R 2 are —H, Y 2 is —H and Z 2 is —NH 2 , and the compounds of this invention has the following structure (II-3):
Representative compounds of structure (II) are set forth in the following Table 2.
TABLE 2
Representative Compounds of Structure (II)
Cpd.
R 1
R 2
X 2
Y 2
Z 2
MW
(II-2)
H
H
—C(CH 3 ) 2 —
1-NH 2
1-NH 2
258
(II-4)
H
H
—C(CH 3 ) 2 —
H
1-NH 2
243
(II-5)
H
H
—C(CH 3 ) 2 —
H
H
228
(II-6)
H
H
—C(CH 3 ) 2 —
1-N(CH 3 ) 2
1-N(CH 3 ) 2
314
(II-7)
H
H
—C(CH 3 ) 2 —
1-NO 2
1-NO 2
318
(II-8)
H
H
—C(CH 3 ) 2 —
H
1-NO 2
273
(II-9)
CH 3
CH 3
—C(CH 3 ) 2 —
H
1-NH 2
271
(II-10)
H
H
—C(CH 3 ) 2 —
H
1-NHC(═NH)NH 2
285
(II-11)
H
H
—C(CH 3 ) 2 —
H
1-N(CH 3 ) 2
271
(II-12)
COCH 3
COCH 3
—C(CH 3 ) 2 —
H
1-NO 2
333
Compound
1 H NMR δ (500 MHz, CDCl 3 )
(II-2)
6.61 (d, 2H), 6.56 (d, 2H), 6.49 (dd, 2H), 1.52 (s, 6H).
(II-4)
7.02 (dd, 2H), 6.58-6.65 (M, 4H), 6.50 (DD, 1H), 1.55 (S, 6H)
(II-6)
6.84-6.80 (m, 6H), 6.68 (d, 2H), 2.61 (s, 12H), 1.58 (s, 6H) (in
CD 3 OD)
(II-7)
10.54 (s, 2H), 8.04 (d, 2H), 7.33 (dd, 2H), 7.08 (d, 2H), 1.70 (s,
6H)
(II-8)
10.52 (s, 1H), 8.05 (d, 1H), 7.34 (dd, 1H), 7.07-7.02 (m, 3H), 6.76-
6.74 (m, 2H), 4.73 (s, 1H), 1.65 (s, 6H)
(II-9)
6.69-6.56 (m, 7H), 3.73 (s, 6H), 1.58 (s, 6H)
(II-10)
7.10-6.67 (m, 7H), 1.60 (s, 6H)
(II-11)
7.09-6.72 (m, 7H), 2.60 (s, 6H), 1.62 (s, 6H)
The compounds of structure (II) may be made by know organic reaction techniques, including those set forth in Example 7 below. For example, representative compounds of structure (II) may be made from the corresponding diphenol (such by 4,4-isopropylidenediphenol) as starting material as represented below by reaction “a”. Nitration provides the mono- and di-nitro derivatives that can be separated by silica gel chromatography. Reduction of the nitro groups provide the corresponding amines. The amines can be further modified by reductive amination using paraformaldehyde and sodium cyanoborohydride. 4,4-isopropyldenediphenol can be reacted with methyl iodide in the presence of potassium carbonate to provide, for example, the monomethyl and dimethyl ethers via reaction “b”, which ethers may be separated by silica gel chromatography. These dialkyloxy derivatives may require more severe nitrating conditions, and nitroniurn tetrafluoroborate may be utilized to furnish the mono- and di-nitro systems as depicted by reaction “c”. Reduction of the nitro functionalities may be achieved using iron in aqueous acetic acid.
In addition, it should be recognized that some of the compounds of structure (II), including starting materials therefor, are commercially available from a number of sources. Further, various references disclose additional techniques, such as published Japanese Application Nos. JP 07/278038 A2 to Hozumi et al. and JP 05/125180 A2 to Endo et al. (both of which are incorporated herein by reference), for the synthesis of compounds of structure (II).
In another aspect, the mitochondria protecting agents of this invention have the following structure (III):
including steroisomers and pharmaceutically acceptable salts thereof, wherein
the dotted line represents a single or double bond;
A 1 is selected from —H and C 1-3 alkyl;
Y 3 is selected from —H, C 1-3 alkyl and —COR d ;
Z 3 is selected from —H, C 1-3 alkyl and —(CH 2 ) m X 3 R d ;
each occurrence of X 3 is selected from —S—, —O— and —NH—;
R 3 is selected from —H, —CH 3 , —CH 2 CH 3 and —R d ;
R d is selected from a guanidino moiety, a cylcoguanidino moiety, and a non-steroidal anti-inflammatory drug; and
m is 1-4.
In one embodiment of structure (III), R 3 is R d , and R d is a guanidino moiety, and the compounds of this invention have the following structure (III-1):
In another embodiment of structure (III), R 3 is R d , R d is a cycloguanidino moiety, and the compounds of this invention have the following structure (III-2):
In still a further embodiment of structure (III), Y 3 is —COR d , where R d is a non-steroidal anti-inflammatory drug (NSAID). Such NSAIDs may be coupled to the nitrogen at the Y 3 position by formation of an amide linkage by, for example, reaction between a carboxylic acid moiety (—COOH) of the NSAID and secondary amine of structure (III) (—NH—). Thus, the designation “—COR d ” should be understood to represent the formation of such an amide linkage. Representative compounds of this embodiment include those of the following structures (III7), (III-8) and (III-9):
Representative compounds of structure (III) are set forth in the following Table 3.
TABLE 3
Representative Compounds of Structure (III)
Cpd
Bond
R 3
X 3
A 1
Y 3
Z 3
MW
(III-3)
double
H
O
CH 3
H
CH 3
189
(III-4)
double
C 2 H 5
O
CH 3
H
CH 3
217
(III-5)
single
C 2 H 5
O
CH 3
H
CH 3
219
(III-6)
double
CH 3
O
CH 3
H
CH 3
203
(III-7)
double
C 2 H 5
O
CH 3
—C═O-naproxen
CH 3
429
(III-8)
double
C 2 H 5
O
CH 3
—C═O-ibuprofen
CH 3
405
(III-9)
double
C 2 H 5
O
CH 3
—C═O-aspirin
CH 3
380
(III-10)
double
H
O
CH 3
CH 3
CH 3
203
Com-
pound
1 H NMR δ (500 MHz, CDCl 3 )
(III-7)
7.64-6.68 (m, 9H), 5.39 (s, 1H), 4.12 (q, 1H), 4.06 (q, 2H),
3.90 (s, 3H), 1.88 (s, 3H), 1.58 (s, 3H), 1.55 (d, 3H), 1.45 (t,
3H), 1.31 (s, 3H)
(III-8)
7.09 (br, 2H), 7.01 (d, 2H), 6.76 (s, 1H), 6.67 (s, 2H), 5.41 (s,
1H), 4.05 (m, 3H), 2.41 (d, 2H), 1.95 (s, 3H), 1.82 (m, 1H),
1.57 (s, 3H), 1.47 (d, 3H), 1.44 (t, 3H), 1.30 (s, 3H), 0.88 (d,
6H)
(III-9)
7.44 (d, 1H), 7.30 (m, 1H), 7.11 (t, tH), 6.92 (d, tH), 6.71 (d,
1H), 6.51 (d, 1H), 6.30 (m, 1H), 5.59 (s, 1H), 3.91 (q, 2H),
2.23 (s, 3H), 2.05 (s, 3H), 1.60 (s, 6H), 1.35 (t, 3H)
(III-10)
6.64-6.46 (m, 3H), 5.40 (s, 1H), 2.71 (s, 3H), 1.94 (s, 3H),
1.21 (s, 6H) (in CD 3 OD)
The compounds of structure (III) may be made by know organic reaction techniques, including those set forth in Example 8 below. For example, representative compounds of structure (III) may be made from ethoxyquin or suitable 6-substituted 2,2,4-trimethyl, 1,2-dihydroquinolines as depicted below by reaction “a”. Alkylation of the secondary amine may be carried out using reductive amination conditions. For example, acylation of the secondary amine to provide the NSAID derivatives may be accomplished by coupling with the corresponding acid halides at elevated temperatures. Alternatively, compounds of structure (III) may be made from the corresponding alcohol (or thiol) by reaction “b”, followed by conversion of the alcohol to the desired substituent.
In addition, it should be recognized that some of the compounds of structure (III), including starting materials therefor, are commercially available from a number of sources. Further, various references disclose additional techniques, such as published Japanese Application No. JP 63/058455 A2 to Tamaki et al. and German Patent No. DE 2156371 (both of which are incorporated herein by reference), for the synthesis of compounds of structure (III).
In another aspect, the mitochondria protecting agents of this invention have the following structure (IV):
including steroisomers and pharmaceutically acceptable salts thereof, wherein
W 1 , W 2 and W 3 are independently selected from —H and C 1-3 alkyl;
X 4 is optionally selected from —NH—, —O— and —S—;
Y 4 is selected from —H and C 1-12 alkyl; and
R 4 is selected from —H, a guanidino moiety, a cylcoguanidino moiety, and a non-steroidal anti-inflammatory drug, or X 4 —R 4 taken together is selected from —CH 2 OH, —OC(═O)CH 3 , and C 1-3 alkyl.
In one embodiment of structure (IV), R 4 is a guanidino moiety, and the compounds of this invention have the following structure (IV-1):
In another embodiment of structure (IV), R 4 is cycloguanidino moiety, and the compounds of this invention have the following structure (IV-2):
In another embodiment of structure (IV), X 4 is O and R 4 is H as represented by structure (IV-3), or X 4 and R 4 taken together is a C 1-3 alkyl as represented by structure (IV-4):
In still a further embodiment of structure (IV), R 4 is a non-steroidal anti-inflammatory drug (NSAID). Such NSAIDs may be coupled via X 4 by formation of a suitable bond, such as an amide, ester or thioester linkage. Thus, when X 4 is oxygen, a an amide or ester may be formed to join the NSAID. For example, an ester linkage may be formed to join a compound of structure (IV) to naproxen, aspirin and ibuprofen as represented by the following structures (IV-6), (IV-7) and (IV-8):
Representative compounds of structure (IV) are set forth in the following Table 4.
TABLE 4
Representative Compounds
Compound
W 1 , W 2 , W 3
Y 4
—X 4 —R 4
MW
(IV-3)
—CH 3
—CH 3
—OH
236
(IV-5)
—CH 3
—CH 3
—CH 3
220
(IV-6)
—CH 3
—CH 3
—O—Naproxen
434
(IV-7)
—CH 3
—CH 3
—O—Aspirin
398
(IV-8)
—CH 3
—CH 3
—O—Ibuprofen
424
(IV-9)
—CH 3
—CH 3
—NHNHC(═NH)NH 2
292
(IV-10)
—CH 3
—CH 3
—OCOCH 3
278
Com-
pound
1 H NMR δ (500 MHz, CDCl 3 )
(IV-3)
3.61 (m, 2H), 2.67 (m, 2H), 2.17 (s, 3H), 2.12 (s, 3H), 2.11
(s, 3H), 2.00 (m, 1H), 1.73 (m, 1H), 1.21 (s, 3H)
(IV-6)
7.65 (m, 3H), 7.39 (m, 1H), 7.11 (m, 3H), 3.97-4.22 (m, 3H),
3.91 (s, 3H), 3.89 (m, 1H), 2.54 (br t, 1H), 2.46 (m, 1H), 2.12
(d, 3H), 1.57 (s, 3H)
(IV-7)
7.84 (dd, 1H), 7.47 (t, 1H), 6.98 (d, 1H), 6.89 (t, 1H)4.36 (m,
2H), 2.68 (t, 2H), 2.33 (s, 3H), 2.34 (s, 3H), 2.09 (s, 3H), 2.02
(s, 3H), 1.39 (br s, 3H)
(IV-8)
7.17 (dd, 2H), 7.06 (d, 1H), 7.01 (d, 1H), 4.07 (1H), 3.72 (q,
1H) 2.54 (t, 1H), 2.42 (m, 2H) 0.87 (m, 6H)
(IV-9)
2.97 (s, 2H), 2.65 (t, 2H), 2.12 (s, 3H), 2.09 (s, 3H), 2.06 (s,
3H), 2.06-1.98 (m, 1H), 1.82-1.74 (m, 1H), 1.27 (s, 3H)
(in CD 3 OD)
(IV-10)
4.25 (s, 1H), 4.11 (dd, 2H), 2.64 (t, 2H), 2.16 (s, 3H), 2.11 (s,
3H), 2.09 (s, 6H), 1.96-1.91 (m, 1H), 1.82-1.75 (m, 1H) 1.28
(s, 3H)
The compounds of structure (IV) may be made by know organic reaction techniques, including those set forth in Example 9 below. For example, representative compounds of structure (IV) may be made from 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) as depicted below by reaction “a”. Reduction of the acid group to the alcohol followed by optionally by coupling with a variety of different moieties, such as an NSAID, provides the corresponding compounds of structure (IV). For example, an aminoguanidine derivative may be prepared by reductive amination of the aldehyde using aminoguanidine and sodium cyanoborohydride. The aldehyde can be formed by Swem oxidation of the primary alcohol as described in the synthesis of Example 9 (see synthetic procedure of compound (IV-9)). The chroman system containing a methylamine substituent may be prepared by hydride reduction of the amide of Trolox via reaction “b”. Keeping the phenolic hydroxyl protected, the amine may be coupled to a variety of moieties, such as NSAIDs, via reaction “c”. Deprotection of the hydroxyl group then provides compounds of structure (IV) wherein —X 4 —R 4 is, for example, —NH—NSAID.
In addition, it should be recognized that the starting materials for the synthesis of compounds of structure (IV) are commercially available from a number of sources.
Pharmaceutically acceptable salts of the compounds of this invention may be made by techniques well known in the art, such as by reacting the free acid or base forms of these compounds with a stoichiometric amount of the appropriate base or acid in water of in an organic solvent. Suitable salts in this context may be found in Remington's Pharmaceuitcal Sciences , 17 th ed., Mack Publishing Co., Easton, Pa., 1985, which is hereby incorporated by reference.
A mitochondria protecting agent of this invention, or a pharmaceutically acceptable salt thereof, is administered to a patient in a therapeutically effective amount. A therapeutically effective amount is an amount calculated to achieve the desired effect. It will be apparent to one skilled in the art that the route of administration may vary with the particular treatment. Routes of administration may be either non-invasive or invasive. Non-invasive routes of administration include oral, buccal/sublingual, rectal, nasal, topical (including transdermal and ophthalmic), vaginal, intravesical, and pulmonary. Invasive routes of administration include intarterial, intravenous, intradermal, intramuscular, subcutaneous, intraperitoneal, intrathecal and intraocular.
The required dosage may vary with the particular treatment and route of administration. In general, dosages for mitochondria protecting agents will be from about 1 to about 5 milligrams of the compound per kilogram of the body weight of the host animal per day; frequently it will be between about 100 μg and about 5 mg but may vary up to about 50 mg of compound per kg of body weight per day. Therapeutic administration is generally performed under the guidance of a physician, and pharmaceutical compositions contain the mitochondria protecting agent in a pharmaceutically acceptable carrier. These carriers are well known in the art and typically contain non-toxic salts and buffers. Such carriers may comprise buffers like physiologically-buffered saline. phosphate-buffered saline, carbohydrates such as glucose, mannose, sucrose, mannitol or dextrans, amino acids such as glycine, antioxidants, chelating agents such as EDTA or glutathione, adjuvants and preservatives. Acceptable nontoxic salts include acid addition salts or metal complexes, eg., with zinc, iron, calcium, barium, magnesium, aluminum or the like (which are considered as addition salts for purposes of this application). Illustrative of such acid addition salts are hydrochloride, hydrobromide, sulphate, phosphate, tannate. oxalate, famarate, gluconate, alginate, maleate, acetate, citrate, benzoate, succinate, malate, ascorbate, tartrate and the like. If the active ingredient is to be administered in tablet form, the tablet may contain a binder, such as tragacanth, corn starch or gelatin; a disintegrating agent, such as alginic acid; and a lubricant, such as magnesium stearate. If administration in liquid form is desired, sweetening and/or flavoring may be used, and intravenous administration in isotonic saline, phosphate buffer solutions or the like may be effected.
Mitochondria protecting agents of this invention also include prodrugs thereof. As used herein, a “prodrug” is any covalently bonded carrier that releases in vivo the active parent drug according the structures (I) through (IV) when such prodrug is administered to the animal. Prodrugs of the compounds of structures (I) through (IV) are prepared by modifying functional groups present on the compound in such a way that the modifications are cleaved, either in routine manipulation or in vivo, to the parent compound. Prodrugs include, but are not limited to, compounds of structures (I) through (IV) wherein hydroxy, amine or sulfhydryl groups are bonded to any group that, when administered to the animal, cleaves to form the free hydroxyl, amino or sulfhydryl group, respectively. Representative examples of prodrugs include, but are not limited to, acetate, formate and benzoate derivatives of alcohol and amine functional groups.
The effectiveness of a compound of this invention as a mitochondria protecting agent may be determined by various assay methods. Suitable mitochondria protecting agents are active in one or more of the following assays for maintenance of mitochondrial structural and functional integrity, or in any other assay known in the art that measures the maintenance of mitochondrial structural and functional integrity. Accordingly, it is an aspect of the invention to provide methods for treating mitochondria associated diseases that include methods of administering compounds that may or may not have known antioxidant properties. However, according to this aspect of the invention, the unexpected finding is disclosed herein that mitochondria protecting agents may exhibit mitochondria protecting activities that are not predictable based upon determination of antioxidant properties in non-mitochondrial assay systems.
A. Assay for Inhibition of Production of Reactive Oxygen Species (ROS) Using Dichlorofluorescin Diacetate
According to this assay, the ability of a mitochondria protecting agent of the invention to inhibit production of ROS intracellularly may be compared to its antioxidant activity in a cell-free environment. Production of ROS may be monitored using, for example by way of illustration and not limitation, 2′,7′-dichlorodihydroflurescein diacetate (“dichlorofluorescin diacetate” or DCFC), a sensitive indicator of the presence of oxidizing species. Non-fluorescent DCFC is converted upon oxidation to a fluorophore that can be quantified fluorimetrically. Cell membranes are also permeable to DCFC, but the charged acetate groups of DCFC are removed by intracellular esterase activity, rendering the indicator less able to diffuse back out of the cell.
In the cell-based aspect of the DCFC assay for inhibition of production of ROS, cultured cells may be pre-loaded with a suitable amount of DCFC and then contacted with a mitochondria protecting agent. After an appropriate interval, free radical production in the cultured cells may be induced by contacting them with iron (III)/ascorbate and the relative mean DCFC fluorescence can be monitored as a function of time.
In the cell-free aspect of the DCFC assay for inhibition of production of ROS, a mitochondria protecting agent may be tested for its ability to directly inhibit iron/ascorbate induced oxidation of DCFC when the protecting agent, the fluorescent indicator and the free radical former are all present in solution in the absence of cells.
Comparison of the properties of a mitochondria protecting agent in the cell-based and the cell-free aspects of the DCFC assay may permit determination of whether inhibition of ROS production by a mitochondria protecting agent proceeds stoichiometrically or catalytically. Without wishing to be bound by theory, mitochondria protecting agents that scavenge free radicals stoichiometrically (e.g., on a one-to-one molecular basis) may not represent preferred agents because high intracellular concentrations of such agents might be required for them to be effective in vivo. On the other hand, mitochondria protecting agents that act catalytically may moderate production of oxygen radicals at their source. or may block ROS production without the agents themselves being altered, or may alter the reactivity of ROS by an unknown mechanism. Such mitochondria protecting agents may “recycle” sothat they can inhibit ROS at substoichiometric concentrations. Determination of this type of catalytic inhibition of ROS production by a mitochondria protecting agent in cells may indicate interaction of the agent with one or more cellular components that synergize with the agent to reduce or prevent ROS generation. A mitochondria protecting agent having such catalytic inhibitor; characteristics may be a preferred agent for use according to the method of the invention.
Mitochondria protecting agents that are useful according to the instant invention may inhibit ROS production as quantified by this fluorescence assay or by other assays based on similar principles. A person having ordinary skill in the art is familiar with variations and modifications that may be made to the assay as described here without departing from the essence of this method for determining the effectiveness of a mitochondria protecting agent, and such variations and modifications are within the scope of this disclosure.
B. Assay for Mitochondrial Permeability Transition (MPT) Using 2-,4-Dimethylaminostyryl-N-Methylpyridinium (DASPMI)
According to this assay, one may determine the ability of a mitochondria protecting agent of the invention to inhibit the loss of mitochondrial membrane potential that accompanies mitochondrial dysfunction. As noted above, maintenance of a mitochondrial membrane potential may be compromised as a consequence of mitochondrial dysfunction. This loss of membrane potential or mitochondrial permeability transition (MPT) can be quantitatively measured using the mitochondria-selective fluorescent probe 2-,4-dimethylarninostyryl-N-methylpyridinium (DASPMI).
Upon introduction into cell cultures, DASPMI accumulates in mitochondria in a manner that is dependent on, and proportional to, mitochondrial membrane potential. If mitochondrial function is disrupted in such a manner as to compromise membrane potential, the fluorescent indicator compound leaks out of the membrane bounded organelle with a concomitant loss of detectable fluorescence. Fluorimetric measurement of the rate of decay of mitochondria associated DASPMI fluorescence provides a quantitative measure of loss of membrane potential, or MPT. Because mitochondrial dysfunction may be the result of reactive free radicals such as ROS, mitochondria protecting agents that retard the rate of loss of DASPMI fluorescence may be effective agents for treating mitochondria associated diseases according to the methods of the instant invention.
C. Assay of Apoptosis in Cells Treated with Mitochondria Protecting Agents
As noted above, mitochondrial dysfunction may be an induction signal for cellular apoptosis. According to this assay, one may determine the ability of a mitochondria protecting agent of the invention to inhibit or delay the onset of apoptosis. Mitochondrial dysfunction may be present in cells known or suspected of being derived from a subject with a mitochondria associated disease, or mitochondrial dysfunction may be induced in normal cells by one or more of a variety of physiological and biochemical stimuli with which those having skill in the art will be familiar.
In one aspect of the apoptosis assay, translocation of cell membrane phosphatidylserine (PS) from the inner to the outer leaflet of the plasma membrane is quantified by measuring outer leaflet binding by the PS-specific protein annexin. (Martin et al, J. Exp. Med . 182:1545, 1995; Fakok et al., J. Immunol . 148:2207, 1992.) In another aspect of the apoptosis assay, induction of specific protease activity in a family of apoptosis-activated proteases known as the caspases is measured, for example by determination of caspase-mediated cleavage of specifically recognized protein substrates. These substrates may include, for example, poly-(ADP-ribose) polymerase (PARP) or other naturally occurring or synthetic peptides and proteins cleaved by caspases that may be known in the art (See, e.g, Ellerby et al., J. Neurosci . 17:6165-6178, 1997.) In another aspect of the apoptosis assay, quantification of the mitochondrial protein cytochrome c that has leaked out of mitochondria in apoptotic cells may provide an apoptosis indicator that can be readily determined. (Liu et al., Cell 86:147, 1996) Such quantification of cytochrome c may be performed spectrophotometrically, immunochemically or by other well established methods for detecting the presence of a specific protein. A person of ordinary skill in the art will readily appreciate that there may be other suitable techniques for quantifying apoptosis, and such techniques for purposes of determining the effects of mitochondria protecting agents on the induction and kinetics of apoptosis are within the scope of the assays disclosed here.
D. Assay of Electron Transport Chain (ETC) Activity in Isolated Mitochondria
As described above, mitochondria associated diseases may be characterized by impaired mitochondrial respiratory activity that may be the direct or indirect consequence of elevated levels of reactive free radicals such as ROS. Accordingly, a mitochondria protecting agent for use in the methods provided by the instant invention may restore or prevent further deterioration of ETC activity in mitochondria of individuals having mitochondria associated diseases. Assay methods for monitoring the enzymatic activities of mitochondrial ETC Complexes I, II, III, IV, and ATP synthetase, and for monitoring oxygen consumption by mitochondria, are well known in the art. (See, e.g., Parker et al., Neurology 44:1090-96, 1994; Miller et al, J. Neurochem . 67:1897, 1996.) It is within the scope of the methods provided by the instant invention to identify a mitochondria protecting agent using such assays of mitochondrial function. Further, mitochondrial function may be monitored by measuring the oxidation state of mitochondrial cytochrome c at 540 nm. As described above, oxidative damage that may arise in mitochondria associated diseases may include damage to mitochondrial components such that cytochrome c oxidation state, by itself or in concert with other parameters of mitochondrial function including but not limited to mitochondrial oxygen consumption, may be an indicator of reactive free radical damage to mitochondrial components. Accordingly, the invention provides various assays designed to test the inhibition of such oxidative damage by mitochondria protecting agents. The various forms such assays may take will be appreciated by those familiar with the art and is not intended to be limited by the disclosures herein, including in the Examples.
For example by way of illustration and not limitation, Complex IV activity may be determined using commercially available cytochrome c that is fully reduced via exposure to excess ascorbate. Cytochrome c oxidation may then be monitored spectrophotometrically at 540 nm using a stirred cuvette in which the ambient oxygen above the buffer is replaced with argon. Oxygen reduction in the cuvette may be concurrently monitored using a micro oxygen electrode with which those skilled in the art will be familiar, where such an electrode may be inserted into the cuvette in a manner that preserves the argon atmosphere of the sample, for example through a sealed rubber stopper. The reaction may be initiated by addition of a cell homogenate or, preferably a preparation of isolated mitochondria, via injection through the rubber stopper. This assay, or others based on similar principles, may permit correlation of mitochondrial respiratory activity with structural features of one or more mitochondrial components. In the assay described here, for example, a defect in Complex IV activity may be correlated with an enzyme recognition site.
The following examples are offered by way of illustration, and not by way of limitation.
EXAMPLES
Example 1
DCFC Assay for Inhibition of ROS Production by Mitochondria Protecting Agents
In the cell-based aspect of the DCFC assay, monolayers of cultured adherent SH-SY5Y human neuroblastoma cells (Biedler et al., Cancer Res . 33:2643, 1973) at or near confluence were rinsed and harvested using trypsin according to standard methods. Single cell suspensions containing 7.5×10 4 cells in 200 μl of medium were seeded into 96-well plates for overnight incubation at 37° C. and 5% CO 2 in a humidified cell atmosphere. The following day the wells were gently rinsed once with warm Hanks balanced saline solution (HBSS, Gibco-BRL), 200 μl of 30 μM dichlorofluorescin-diacetate (DCFC-DA, Molecular Probes, Eugene, Oreg.) were added to each well and cultures were incubated for 2 hours at 37° C./ 5% CO 2 . The excess DCFC-DA was removed by needle aspiration and each well was gently rinsed twice with HBSS. Each well then received 80 μl of HBSS and 10 μl of mitochondria protecting agent, or vehicle control, diluted into HBSS from stock solutions of dimethylformamide or dimethylsulfoxide. The final concentration of the organic solvent was maintained at or below 0.1% (v/v) in HBSS while in contact with cells.
Cells were equilibrated for 15 minutes at room temperature with the mitochondria protecting agent (or vehicle control) and then 10 μl of fresh 500 μM ferric chloride/300 μM ascorbate solution was added to initiate free radical formation. Fluorescence of each microculture in the 96-well plate was quantified immediately using a Cytofluor fluorimetric plate reader (model #2350, Millipore Corp., Bedford, Mass.; excitation wavelength=485 nm, emission wavelength=530 μnm) and t 0 fluorescence was recorded. The 96-well plates were incubated 30 minutes at 37° C./5% CO 2 and fluorescence at 530 nm was again measured (t 30 ). The change in relative mean fluorescence (RMF) over the 30 minute period was calculated for each well.
The cells were then harvested by trypsinization and counted using a hemacytometer in order to normalize the data as Δ(t 30 ,−t 0 )RMF per cell. The efficacy of a candidate mitochondria protecting agent was determined by comparing its ability to inhibit ROS production relative to the vehicle control.
In the cell-free aspect of the DCFC assay, candidate mitochondria protecting agents are further evaluated for their ability to inhibit ROS oxidation of DCFC in solution in a microtitre plate format. Stock compound solutions are usually prepared in dimethylformamide (DMF) or dimethylsulfoxide (DMSO) and diluted further into working concentrations using HBSS. Inhibition studies are carried out over a range of concentrations. Ten μl of the compound solution or vehicle control and 10 μl of a 300 μM DCFC solution in HBSS buffer are added to 60 μl of HBSS buffer. Ten pi of fresh 500 μM ferric chloride/ 300 μM ascorbate solution is then added to initiate free radical formation. Fluorescence of each well in the 96-well plate is quantified immediately using a Cytofluor tluorimetric plate reader (model #2350, Millipore Corp., Bedford, Mass.; excitation wavelength=485 nm; emission wavelength=530 nm) and fluorescence is recorded. Ten μl of a 0.5% aqueous H 2 O 2 solution is then added to initiate hydroxyl radical formation through Fenton chemistry and a second fluorimetric reading is taken after 10 min. The concentration at which a candidate mitochondria protecting agent exerts 50% of its maximal inhibitory activity (IC 50 ) is calculated from a two-dimensional plot of relative fluorescence units against inhibitor concentration.
Data providing IC 50 values of representative mitochondria protecting agents of this invention in the cell-based assay described above are presented below in Table 6.
TABLE 6
Inhibition of ROS by Mitochondria Protecting Agents:
DCFC Assays
IC 50
Cell-
Compound
Based
(I-2)
25
nM
(I-3)
65
nM
(I-5)
100
nM
(I-6)
200
nM
(I-8)
400
nM
(I-10)
120
nM
(I-11)
600
nM
(I-12)
600
nM
(I-13)
200
nM
(II-2)
35
nM
(II-4)
55
nM
(II-5)
1
μM
(II-6)
10
nM
(II-10)
1
μM
(III-3)
70
nM
(III-4)
20
nM
(III-5)
30
nM
(III-6)
20
nM
(III-7)
100
nM
(III-8)
500
nM
(III-9)
160
nM
(IV-3)
300
nM
(IV-5)
20
nM
(IV-6)
30
nM
(IV-7)
50
nM
(IV-8)
40
nM
(IV-9)
1
μM
Example 2
Assay for Mitochondria Permeability Transition Using DASPMI
The fluorescent mitochondria-selective dye 2-,4-dimethylaminostyryl-N-methylpyridinium (DASPMI, Molecular Probes, Inc., Eugene, Oreg.) is dissolved in HBSS at 1 mM and diluted to 25 μM in warm HBSS. In 96-well microculture plates, cultured human cells from an individual known or suspected of having a mitochondria associated disease, or normal (control) cells, are incubated for 0.5-1.5 hrs in 25 μM DASPMI in a humidified 37 C/5% CO 2 incubator to permit mitochondrial uptake of the fluorescent dye. Culture supernatants are then removed and candidate mitochondria protecting agents diluted into HBSS from DNF or DMSO stocks, or vehicle controls, are added at various concentrations.
Fluorescence of each microculture in the 96-well plate is quantified immediately using a Cytofluor fluorimetric plate reader (model #2350, Millipore Corp., Bedford, Mass.; excitation wavelength=485 nm; emission wavelength=530 nm) and t 0 fluorescence is recorded. Thereafter, fluorescence decay is monitored as a function of time and the maximum negative slope (V-max) is calculated from a subset of the data using analysis software. In addition, the initial and final signal intensities are determined and the effects of candidate mitochondria protecting agents on the rate of signal decay is quantified.
Example 3
Effect of Mitochondria Protecting Agents on Apoptosis
In 96-well microculture plates. cultured human cells from an individual known or suspected of having a mitochondria associated disease, or normal (control) cells or cell lines, are cultured for a suitable period in the presence or absence of physiological inducers of apoptosis (e.g., Fas ligand. TNF-α, or other inducers of apoptosis known in the art) and in the presence or absence of candidate mitochondria protecting agents.
Exteriorization of plasma membrane phosphatidyl serine (PS) is assessed by adding to the 96 well plate annexin-fluorescein isothiocyanate conjugate (annexin-FITC, Oncogene Research Products, Cambridge, Mass.) dissolved in a suitable buffer for binding to cell surfaces at a final concentration of 5 μg/well. (Martin et al., J. Exp. Med . 182:1545, 1995) After 15-30 min in a humidified 37 ° C./ 5% CO 2 incubator, cells are fixed in situ using 2% formalin, washed to remove non-specifically bound FITC and read using a Cytofluor fluorimetric plate reader (model #2350, Millipore Corp., Bedford, Mass.; excitation wavelength=485 nm; emission wavelength=530 nm) to quantify cell surface bound annexin-FITC as a measure of outer leaflet PS, a marker for cells undergoing apoptosis.
Caspase-3 activity is assessed by diluting the fluorogenic peptide substrate Asp-Glu-Val-Asp-AMC (DEVD-AMC) from a DMSO stock solution into culture media to a final concentration of 20 μM for uptake by cells. Substrate cleavage liberates the fluorophore, which is measured continuously using a Cytofluor fluorimetric plate reader (model #2350, Millipore Corp., Bedford, Mass.; excitation wavelength=4355 nm; emission wavelength 460 nm). Caspase-1 is measured using the same protocol as that for caspase-3, except the caspase-1 specific fluorogenic substrate Tyr-Val-Ala-Asp-Z (Z-YVAD), is substituted for DEVD-AMC and fluorimetry is conducted using 405 nm excitation and 510 nm emission.
Cytochrome c released from mitochondria of cells undergoing apoptosis is recovered from the post-mitochondrial supernatant and quantified by reverse phase HPLC using a C-18 column, gradient elution (0-45% methanol in phosphate buffer, pH 7.4) and UV absorbance at 254 nm. Commercially-obtained authentic cytochrome c serves as the standard. Recovered cytochrome c is also quantified immunochemically by immunoblot analysis of electrophoretically separated post-mitochondrial supernatant proteins from apoptotic cells, using cytochrome c-specific antibodies according to standard and well accepted methodologies.
Example 4
Effect of Mitochondria Protecting Agents on Ionomycin Induced Apoptosis
SH-SY5Y neuroblastoma cells (1×10 5 cells) are rinsed with one volume 1×PBS, and then treated with 10 μM ionomycin (Calbiochem, San Diego, Calif.) in DMEM supplemented with 10% fetal calf serum (FCS) (Gibco, Life Technologies, Grand Island, N.Y.) for 10 minutes, followed by two washes with DMEM (10% FCS). After 6h incubation at 37° C. in DMEM (10% FCS), cells are visualized by light microscopy (20X magnification). Approximately 80% of ionomycin treated cells exhibit membrane blebbing, indicative of entry by those cells into a final stage of apoptosis, compared to negligible apoptosis (<5%) in untreated cells. When cells are simultaneously treated with ionomycin and 2 mM creatine, the proportion of cells undergoing apoptosis as evidenced by membrane blebbing is reduced to approximately 10%. Candidate mitochondria protecting agents are assayed to determine whether they provides the same magnitude of protection from induction of apoptosis as does creatine in this ionomycin induced apoptosis assay.
Example 5
Effect of Mitochondria Protecting Agents on Ionomycin Induced Apoptosis
Control cybrid cells (MixCon) produced by fusing ρ 0 SH-SY5Y neuroblastoma cells with mitochondria source platelets from normal subjects, and 1685 cells, a cybrid cell line produced by fusing ρ 0 SH-SY5Y cells with mitochondria source platelets from an Alzheimer's Disease patient (Miller et al., 1996 J. Neurochem. 67:1897-1907), are grown to complete confluency in 6-well plates (˜3×10 6 cells/well). Cells are first rinsed with one volume 1×PBS, and then treated with 10 μM ionomycin in the absence or presence of 100 μM of a candidate mitochondria protecting agent, in DMEM supplemented with 10% FCS, for 1 minute. At one minute, cells are rinsed twice with five volumes of cold 1×PBS containing a cocktail of protease inhibitors (2 μg/ml pepstatin, leupeptin, aprotinin, and 0.1 mM PMSF). Cells are then collected in one ml of cold cytosolic extraction buffer (210 mM mannitol, 70 mM mannitol, 5 mM each of HEPES, EGTA, glutamate and malate, 1 mM MgCl 2 , and the protease inhibitor cocktail at the concentrations given above. Homogenization is carried out using a type B dounce homogenizer, 25× on ice. Cells are spun at high speed in an Eppendorf microfuge for five minutes to separate cytosol from intact cells, as well as cell membranes and organelles. The supernatant is collected and an aliquot saved, along with the pellet, at −80° C. for citrate synthase and protein assays.
Cytochrome c antibody is covalently bound to solid support chips containing a pre-activated surface (ProteinChip, Ciphergen, Palo Alto, Calif.). The spot to be treated with antibody is initially hydrated with 1 μl of 50% CH 3 CN and the antibody solution is added before the CH 3 CN evaporated. The concentration of the antibody is approximately 1 mg/ml in either Na 3 PO 4 or PBS buffer (pH 8.0). The chip is placed in a humid chamber and stored at 4° C. overnight. Prior to addition of the cytosolic extract, residual active sites are blocked by treatment with 1.5 yl ethanolamine (pH 8.0) for thirty minutes. The ethanolamine solution is removed and the entire chip is washed in a 15 ml conical tube with 10 ml 0.05% Triton-X 100 in 1×PBS. for 5 minutes with gentle shaking at room temperature. The wash buffer is removed and the chip is sequentially washed. first with 10 ml 0.5 M NaCl in 0.1 M NaOAc (pH 4.5), and then with 0.5 M NaCl in 0.1 M Tris (pH 8.0). After removal of the Tris-saline buffer, the chip is rinsed with 1×PBS and is ready for capture of the antigen.
Fresh supernatant samples are spotted onto the Ciphergen ProteinChip containing covalently-linked anti-cytochrome c antibody (Pharmingen. San Diego, Calif.). For optimal antibody-cytochrome c interaction, 100 μl of the supernatant is used and the incubation is carried out overnight with shaking at 4° C. in a Ciphergen bioprocessing unit. The supernatant is then removed and the spots on the chip are washed in the bioprocessing unit three times with 200 μl of 0.1% Triton-X 100 in 1×PBS, and then twice with 200 μl of 3.0 M urea in 1×PBS. The chips are then removed from the bioprocessor and washed with approximately 10 ml of dH 2 O. The chips are then dried at room temperature prior to the addition of EAM solution (e.g. sinapinic acid, Ciphergen, Palo Alto, Calif.). A suspension of the EAM is made at a concentration of 25 mg/ml in 50% CH 3 CN/H 2 O containing 0.5% TFA. The saturated EAM solution is clarified by centrifugation and the supernatant is used for spotting on the ProteinChip surface. Prior to the addition of EAM to the chip, an internal standard of ubiqutin is added to the EAM solution to provide a final concentration of 1 pmol/μl. The quantification of cytochrome c released from mitochondria upon ionomycin treatment is based on normalization to the ubiquitin peak in the mass spectrum and the protein content of the cytosolic extracts. Citrate synthase activity of cytosolic extracts is measured to rule out the possibility of mitochondrial lysis during the sample preparation procedure. Data from this assay may be represented, for example, by graphing cytochrome c release in cells undergoing ionomycin induced apoptosis, and attenuation of cytochrome release in cells treated with a candidate mitochondria protecting agent compound at the same time ionomycin is introduced.
Example 6
Synthesis and Characterization of Representative Mitochondria Protecting Agents of Structure (I)
This example illustrates the synthesis and characterization of representative mitochondria protecting agents having structure (I) of this invention.
Structure (I-6):
To a solution of 123 mg (0.75 mmole) of 4-allyl-2-methoxyphenol (eugenol) and 1.4 gm (7.5 mmole)of p-toluenesulfonhydrazide in 15 ml of dimethoxyethane under reflex was added a solution of 1.7 gm of NaOAc in 15 ml water over a 4 hour period. The mixture was cooled to room temperature, poured into 20 ml of water, and extracted three times with 30 ml of CH 2 Cl 2 . The combined organic layers were washed with 50 ml of water, dried over MgSO 4 , and concentrated under vacuo. The resulting solid was flash chromatographed over silica gel using 10% ethyl acetate in hexane to afford 60 mg of 2-methoxy-4-propylphenol in 48% yield.
To 38 mg (0.23 mmole) of 2-methoxy4fpropylphenol in 0.4 ml of CH 2 Cl 2 at −78° C. and under argon was added 254 μl (0.252 mmole) of a 1M BBr 3 solution in CH 2 Cl 2 . The reaction mixture was stirred at −78° C. for one hour and then warmed to 0° C. The reaction was quenched by addition of 2 ml of water. The mixture was extracted three times with 5 ml of CH 2 Cl 2 dried over anhydrous Na2SO 4 and concentrated by rotary evaporation. The crude product was flash chromatqgraphed over silica gel using 25% ethyl acetate in hexane to farnish 30 mg of 2-hydroxy4-propylphenol, Structure (I-6), in 86% yield.
Structure (I-8):
To 60 mg (0.39 mmole) of 2-hydroxy4-propylphenol under argon was added 0.9 ml of pyridine and 0.75 ml of acetic anhydride. The mixture was stirred for 18 hours at 23° C. The reaction mixture was then taken up in 35 ml hexane, washed with 10 ml of brine, dried over anhydrous Na 2 SO 4 and concentrated. The product was purified by flash chromatography over silica gel using 15% ethyl acetate in hexane to provide 87 mg of Structure (I-8) in 93% yield.
Structure (I-2):
Concentrated sulfuric acid (204 μl) was carefully added of to 700 μl of water at 0° C. Then 223 mg (2.63 mmole) of NaiO 3 was added and the mixture was stirred at 0° C. till the salt went into solution. 4-Octylphenol (309 mg; 1.5 mmole) was then added in two equal portions. The reaction mixture turned reddish in color. The reaction was allowed to proceed at 0° C. for 10 min and then at 23° C. for 3 hours. The mixture was taken up in 60 ml of ethyl acetate, washed with 20 ml of brine, dried over anhydrous Na 2 SO 4 and concentrated. Purification by flash chromatography using 5% ethyl acetate in hexane provide 257 mg of 2-nitro-4-octylphenol in 68% yield.
To 95.4 mg(0.38 mmole) of 2-nitro-4-octylphenol in 2 ml of 1:1 glacial acetic acid and water mixture at 85-90° C. was added 0.35 gm of activated iron in three portions over a 15 min period. The reaction was allowed to proceed at the same temperature for 45 min. The reaction mixture was diluted then with 5 ml of water and extracted pith 20 ml ethyl acetate. The organic layer was dried over anhydrous Na 2 SO 4 and concentrated by rotary evaporation. The crude product was flash chromatographed over silica gel using 30% ethyl acetate in hexane to yield 56 mg of 2-amino4octyl phenol, Structure (I-2), in 67% yield.
Structure (I-3):
The compound of Structure (I-3) may be prepared in the same manner as set forth above for Structure (I-2), but using t-octylphenol in place of 4-octylphenol.
Example 7
Synthesis and Characterization of Representative Mitochondria Protecting Agents of Structure (II)
This example illustrates the synthesis and characterization of representative mitochondria protecting agents having structure (II) of this invention.
Structure (II-4):
Concentrated sulfuric acid (816 μl) was added dropwise to 2.8 ml water at 0° C., following which 892 mg (10.5 mmole) NaNO 3 was added and dissolved by magnetic stirring at 0° C. 4,4′-Isopropylidenediphenol (682 mg, 3 mmole) was added and the mixture was stirred for 15 minutes at 0° C. and then for 16 hours at 23° C. The reaction products were taken up in 120 ml of ethyl acetate, washed with 50 ml of water, dried over anhydrous Na 2 SO 4 and concentrated. The crude material was flash chromatographed over silica gel using 10% ethyl acetate in hexane to afford 200 mg (24% yield) of the mono-nitro derivative and 457 mg (48% yield) of the di-nitro compound.
To 66 mg (0.24 mmole) of the mono-nitro compound in 2 ml of 1:1 glacial acetic acid and water at 85-90° C. was added 0.3 gm activated iron in 3 portions over a 15 minute period. The reaction was allowed to proceed at the same temp for 45 min, with stirring. The reaction mixture was then diluted with 5 ml of water, extracted with 20 ml of ethyl acetate, dried over anhydrous Na 2 SO 4 and concentrated. Silica gel flash chromatography of the crude product using 10% methanol in chloroform provided 55.7 mg of Structure (II4) in 96% yield.
Structure (II-2):
Structure (II-2) was prepared by a similar procedure from the di-nitro compound in 45% yield.
Structure (II-6):
To 25 mg of the diamine in 0.85 ml of acetic acid was added 33 mg of paraformaldehyde and 71 mg of NaCNBH 3 . The solution was stirred for 16 hrs at 23° C. and then poured into 20 ml of saturated NaaHCO 3 and then extracted with 2×25 ml of ethyl acetate. The solution was dried over anhydrous Na 2 SO 4 , concentrated and the residue was purified by flash chromatography using a 5% CH 3 OH/CHCl 3 solvent system to afford 17 mg of the hexamethyl-benzhydryl derivative in 54% yield. (The N-methyl analogue of 2,2,4-trimethyl-1,2-dihydro-quinolin-6-ol, structure (III-11) may be prepared in an analogous manner.)
Structure (II-9)
To 171 mg of 4,4-isopropylidenediphenol (0.75 mmole) in 5 ml of dry DME was added 1.12 gm of K 2 CO 3 and 396 μl of CH 3 I (6.4 mmol) and the mixture was refluxed for 16 hours. The mixture was filtered, the residue was washed with ethyl acetate and combined with the filtrate. The solution was evaporated and the crude compound was flash chromatographed using 30% ethyl acetate in hexane to afford the 118 mg of dimethoxy derivative as one of the products (69% yield).
To 77 mg of the dimethoxy derivative in 560 ml of dry sulfolane at 4° C. was added 590 ml of a 0.5 M solution of nitronium tetrafluoroborate in sulfolane. The mixture was stirred for 15 min under argon, then diluted with 80 ml of ethyl ether. The solution was washed with 4×20 ml of water, dried over anhydrous magnesium sulfate and concentrated. The products were subjected to silica gel flash chromatography using 30% ethyl acetate in hexane to afford 29 mg of mono-nitrated product and 15 mg of the di-nitro derivative.
To 36 mg of the mono-nitro derivative in 1 ml of 1:1 glacial acetic acid/H2O was added 130 mg of activated iron and the mixture was refluxed at 85-90° C. for 45 min. Water (5 ml) was then added and the product was extracted with ethyl acetate, and concentrated in vacuo. The product was then purified by preparative thin layer chromatography using 50% ethyl acetatefhexane as the eluting system.
Structure (II-10):
To a round-bottomed flask fitted with an argon inlet were placed compound (II-4) (30 mg, 0.123 mmol), 1,3-bis(tert-butoxycarbonyl)-2-methyl-2-thiopseudourea (II-46 mg, 0.16 mmol) and dry N,N-dimethylformamide (630 μl). To the above stirred solution at room temperature were added triethylamine (52 μl, 0.37 mmol) and mercuric chloride (37 mg, 0.13 mmol). The resulting mixture was stirred at room temperature, whereupon a white precipitate soon formed. After stirring for 3 h, the reaction mixture was diluted with ethyl acetate and filtered through a pad of Celite. The filtrate was washed with 5% aqueous sodium carbonate (1×10 ml), water (2×10 ml) and brine (1×10 ml). The solution was dried over anhydrous magnesium sulfate and concentrated to provide the crude product. Purification by flash chromatography using 20% ethyl acetatelhexane provided 45 mg of the Bocprotected guanidine derivative.
Deprotection of the Boc group was achieved by treatment with trifluoroacetic acid (TFA). Thus, to 45 mg of the benzhydryl-Boc derivative under argon was added 1 ml of 50% TFA/CH 2 Cl 2 solution and the mixture was stirred for 3 h at 23° C. The solvent was then removed by rotary evaporation to provide 27 mg of pure guanidine derivative of structure (II-10) (single spot by TLC using 20% CH 3 OH/CHCl 3 solvent system containing 1% HOAc).
Example 8
Synthesis and Characterization of Representative Mitochondria Protecting Agents of Structure (III)
This example illustrates the synthesis and characterization of representative mitochondria protecting agents having structure (III) of this invention.
Coupling of NSAIDs with 6-ethoxy-1,2-dihydro-2,2,4-trimethylguinoline (ethoxyguin)
Ibuprofen, (S)-(+)-4isobutyl-α-methylphenylacetic acid, and naproxen, (S)-(+)-6-methoxy-α-2-methyl-2-naphthaleneacetic acid, were converted to their acid chlorides by the procedure described below. Acetyl salicyloyl chloride is commercially available from Aldrich Chemical Co. (Milwaukee, Wis.). The ibuprofen conjugate preparation is representative of the coupling procedure. Thus, to 103 mg (0.5 mmol) of ibuprofen in 7 ml of dry benzene was added 54 μl of oxalyl chloride that results in rapid gas evolution. The mixture was stirred for 30 min at 23° C. and then the solvent was removed by rotary evaporation. The oily residue was taken up in 7 ml of dry THF and the solvent was evaporated again to remove traces of oxalyl chloride. The acid chloride product was kept under high vacuum for an additional 30 min and used in the next step without purification. A solution of 74 μl (˜0.35 mmol) of ethoxyquin and the acid chloride from the previous reaction in 1 ml of dry benzene was stirred for 72 hrs at 23° C. followed by reflux for 4 hrs. The solvent was removed in vacuo and the product was purified by flash chromatography using 13% ethyl acetateihexane solvent system to furnish 82 mg of the ibuprofen conjugate in 57% yield. The naproxen conjugate and the acetylsalicylic acid conjugate were obtained in 57% and 10% yields respectively.
Synthesis of 6-alkylthio-1,2-dihydro-2,2,4-trimethylquinolines
6-Alkylthio-1,2-dihydro-2,2,4-trimethylquinolines are prepared by a two step procedure from 1-acetyl-1,2-dihydro-2,2,4-trimethylquinoline-6-thiol (1). Compound (2) was synthesized by the procedure described by Pearce and Wright (U.S. Pat. No. 5,411,969) from 2,2,4trimethyl-1,2ihydroquinolin-6-ol (1), that is listed in the Salor catalogue (S13857-8) and can be ordered through Sigma or Aldrich Chemicals. Briefly, (2) is synthesized by treatment of (1) with dimethylthiocarbamoyl chloride to afford the O-aryl dimethyl thiocarbamate that is rearranged to the S-aryl thiocarbamate using p-toluenesulfonic acid as the acid catalyst. The resulting intermediate is reacted with acetic anhydride to provide the N-acetyl derivative that is then treated with sodium methoxide in methanol to unmask the dimethylthiocarbamate to furnish the thiol (2).
Synthesis of 1,2-dihydro-6-thiomethoxy-2,2,4-trimethylquinoline
To 150 mg (0.61 mmol) of 1-acetyl-1,2-dihydro-2,2,4-trimethylquinoline-6-thiol (2) in 3 ml of anhydrous acetonitrile and under argon was added 126 mg (0.92 mmol) of potassium carbonate and 38 μl (0.61 mmol) of methyl iodide. The mixture was stirred at room temperature for 2 hours and then was taken up in 30 ml of ethyl acetate. washed with water and then brine. The organic layer was dried over anhydrous MgSO 4 , filtered and concentrated. 1-Acetyl-1,2,4-dihydro-6-thiomethoxy-2,2,4-trimethylquinoline was purified by silica gel flash chromatography using ethyl acetate/hexane as the eluting system.
To 1-acetyl-1,2-dihydro-2,2,4-methylquinoline-6-thiol (90 mg, 0.35 mmol) in 2 ml of dry THF at −10° C. and under argon was added in dropwise fashion 1.75 ml of a 1 M THF solution of lithium triethylborohydride. The mixture wasstirred for 10 min, then warmed to 23° C. and stirred for an additional 16 hours. Excess borohydride reagent was quenched by addition of saturated NH 4 Cl. The mixture was poured into water and then extracted with ethyl acetate. The organic layer was then washed with brine, dried over anhydrous MgSO 4 , filtered and concentrated. The crude aterial was purified by silica gel flash chromatography using ethyl acetate,lhexane to yield pure 1,2-dihydro-6-thiomethoxy-2,2,4-trimethylquinoline.
Example 9
Synthesis and Characterization of Representative Mitochondria Protecting Agents of Structure (IV)
6-t-butyldimethylsilyloxy-2,5,7,8-tetramethylchroman-2-carboxylic acid t-butyldimethylsilyl ester
To 500 mg (2 mmole) of Trolox in 2.8 ml of anhydrous DMF and under argon was added 952 mg (14 mmole) of imidazole and 1.06 gm (7 mmole) of t-butyldimethylsilyl chloride and the mixture was stirred at 23° C. for 72 hours. The reaction mixture was taken up in 200 ml of CH 2 Cl 2 and washed successively with 30 ml each of saturated sodium bicarbonate and brine. The organic layer was dried over anhydrous Na 2 SO 4 and then the solvent was removed in vacuo to provide 2.01 gm of crude reaction product. The carboxylic acid derivative was used in the next step without further purification
(6-t-butyldimethylsilyloxy-2,5,7,8-tetramethyl-3,4-dihydro-2H-1-benzo[1,2-b]pyran-2yl)methanol
To 511 mg (13.8 mmole) of lithium aluminum hydride (LAH) under argon was added 17 ml of anhydrous THF and the mixture was cooled to 0° C. The crude reaction product (2.01 gm) from the previous reaction was dissolved in 24 ml of anhydrous THF and the solution was added dropwise to the LAH suspension. The reaction mixture was stirred at 0° C. for 2 hours following which excess LAH was quenched by addition of saturated aqueous sodium sulfate solution. The resulting flocculate was poured over a bed of celite in a sintered glass funnel and ˜150 ml ethyl acetate was used to wash the celite bed. The solvent was removed by rotary evaporation and the desired silyl ether-alcohol derivative was purified by silica gel flash chromatography using chloroform to provide 583 mg (83% yield for two steps) of isolated material. 1 H NMR (500 MHz. CDCl 3 ) d 3.60 (m, 2H), 2.10 (m, 2H), 2.10 (s. 3H), 2.07 (s, 3H)2.06 (s, 3H), 1.21 (s. 31H). 1.05 (s. 9H), 0.119 (s, 3H)116 (s. 3H).
Structure (IV-6) (Chormanol-Nuuproxen Coniugate)
To 57.3 mg (0.16 mmole) of (6-t-butyldimethylsilyloxy-2,5,7,8-tetramethyl-3,4dihydro-2H-1-benzo[1,2-b]pyran-2yηmethanol in 1.7 ml of dry CH 2 Cl 2 was added 37.5 mg (0.16 mmol) of (+)-6-methoxy-α-methyl-2-napthaleneacetic acid (naproxen), 37 mg (0.18 mmole) 1,3-dicyclohexylcarbodiimide and 5.7 mg of 4-dimethylamino pyridine. The reaction mixture was stirred under argon for five hours and then the urea byproduct was removed by filtration. The product of the coupling reaction was purified by flash chromatography over silica gel using 10% ethyl acetate in to afford 78.2 mg (85%G) of pure material.
To a solution of 30.7 mg (0.06 mmole) of the above silyloxy ether derivative in 1 ml of anhydrous THF at 0° C. and under argon was added 164 μl (0.164 mmole) of a 1 M tetrabutylarunoniumfluoride solution in THF. The reaction was kept at 0° C. for 10 min and then at 23° C. for 30 min. The mixture was taken up in 30 ml ethyl acetate, washed with brine, dried over anhydrous Na 2 SO 4 and concentrated. The naproxen-chromanol conjugate was purified by preparatory thin layer chromatography using 20% ethyl acetate in hexane as the eluting solvent to provide 6 mg of purified material.
Structure (IV-7) (Chromanol-Salicylic acid Conjugate)
Structure (IV-7) was made in the same manner as disclosed above, but employing salicylic acid in place of naproxen.
Structure (IV-8) (Chromanol-Ibuprofen Conjugate)
Structure (IV-8) was made in the same manner as disclosed above, but employing salicylic acid in place of naproxen.
Structure (IV-3)
To a suspension of 251 mg (6.6 mmole) of LAH in 2 ml of anhydrous THF was added dropwise a solution of trolox (0.5 gm, 2 mmole) in 10 ml of anhydrous THF The solution was stirred for two hours and excess LAH was quenched by addition of saturated aqueous sodium sulfate solution. The aluminium salts were removed by filtering through a celite bed, the organic solution was dried over anhydrous NaSO 4 and concentrated. The crude mixture was purified by silica gel flash chromatography using 0.5/1/98.5 methanol/acetic acid/chloroform eluent to afford 323 mg (68%) of Structure (IV-3).
Structure (IV-9)
Lithium aluminium hydride (473 mg, 12.7 mmol) was suspended in 10 ml of dry THF and 1 gm of Trolox (4 mmol) in 12 ml of THF was added under argon. The reaction mixture was stirred for 2 hrs at 23° C. and then quenched by carefully pouring it into an ice/water mixture. The aqueous layer was extracted with 100 ml of ethyl acetate. The organic layer was separated, washed with brine, dried over anhydrous Na 2 SO 4 , and concentrated. The residue was purified by flash chromatography using 1:1:98 methanollacetic acid/CHCl 3 solvent system to afford 936 mg of diol (94% yield).
The primary alcohol was oxidized to the aldehyde using Swem oxidation conditions. Thus, to oxalyl chloride (100 μl) in 2 ml of CH 2 Cl 2 at −78° C. and under N 2 was added 100 μl of DMSO and the reaction mixture was stirred for 10 min. A solution of 97 mg of the above diol in 1 ml of CH 2 Cl 2 was then added and the reaction was stirred for 15 min. Triethylamine (750 μl) was then added and the mixture was warmed to 23° C. Water (1.5 ml) was then added and the mixture was stirred for an additional 10 min. The crude product was extracted with CH 2 Cl 2 , dried over anhydrous Na 2 SO 4 concentrated and flash chromatographed using 25% ethyl acetate in hexane to furnish 56 mg of the aldehyde in 67% yield. This material was used immediately in the subsequent reaction.
A mixture of 46 mg of aldehyde (0.2 mmol), 43.3 mg of aminoguanidine (0.4 mmol) and 123 mg of NaCNBH 3 in 2 ml of acetic acid was stirred for 16 hrs at 23° C. The reaction mixture was then poured into 50 ml of saturated NaHCO 3 and then extracted with 2×50 ml of ethyl acetate. The solution was dried over anhydrous Na 2 SO 4 , concentrated and the residue was purified by flash chromatography using a 1:14:85 HOAc/CH 3 OH/CHCl 3 solvent system to afford 54 mg of structure (IV-9). MS 293.3 (M+1)
From the foregoing, it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.
|
The present invention relates generally to mitochondria protecting agents for treating diseases in which mitochondrial dysfunction leads to tissue degeneration and, more specifically, to compounds, compositions and methods related to the same. The methods of this invention involve administration of a pharmaceutically effective amount of a mitochondria protecting agent to a warm-blooded animal in need thereof, and composition of this invention contain a mitochondria protecting agent in combination with a pharmaceutically acceptable carrier or diluent. Mitochondrial associated diseases which may be treated by the present invention include (but are not limited to) Alzheimer's Disease, diabetes mellitus. Parkinson's Disease, neuronal and cardiac ischemia. Huntington's disease and stroke.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. patent application Ser. No. 11/527,977 filed Sep. 28, 2006, now U.S. Pat. No. 7,905,117, issued Mar. 15, 2011.
FIELD OF THE INVENTION
The present invention relates to a to a process for the manufacture of a shaping camisole garment such as a short shirt, negligee jacket or a short sleeveless undergarment all for women and to a process for the manufacture of camisole type garments.
BACKGROUND OF THE INVENTION
Manufacturers constantly seek new, cost-effective, relatively inexpensive processes for manufacturing clothing for everyday use. Moreover, consumers are interested in active wear or light support garments that are comfortable and relatively inexpensive.
Previous and current methods for producing active wear or light support garments for women similar to those contemplated by the present invention usually require pieces of fabric of varying densities and support characteristics to be cut into specific patterns in a multi-step process for assembly into articles of clothing. The resulting garment usually resembles a girdle or some other undergarment without any substantial fashion value as an outer garment because of the numerous seams and design curvatures required to be employed. The manufacturing process is also labor intensive and relatively slow because of the numerous sewing stages required. From the foregoing discussion, it will be apparent that there is a need to develop a manufacturing process and a product made by that process that will enable the manufacture of a cost-effective, relatively inexpensive, high manufacturing efficiency body shaping garment having desirable fashion characteristics. It is to that objective that the present invention is directed.
SUMMARY AND OBJECTIVES OF THE INVENTION
One aspect of the present invention is a process for the manufacture of a camisole garment to be worn about the upper body comprising the steps of providing an inner body portion having front and back fabric portions each having first and second vertical edges formed from 40 denier nylon and 40 denier spandex yarn and having a minimum stretch characteristic of 80%, shaping each of the inner body formed front and back fabric portions to define an arm-encircling opening, a top edge and a strap formed thereby, joining the inner body front and back portions along abutting vertical edges to form the inner body portion, providing an outer body portion having front and back portions to achieve a desired appearance, shaping each of the outer body formed front and back fabric portions to define an arm-encircling opening, a top edge and a strap formed thereby, joining the outer body front and back portions along abutting vertical edges to form the outer body portion, and joining the inner body portion to the outer body portion to provide one double layer shaping camisole.
Another feature of the present invention is to provide a shaping camisole formed of two (2) body-encircling portions made on a multi-needle knitting machine each having arm-receiving openings, a top edge and straps formed thereby. The camisole has an inner body-encircling portion having front and back portions formed from nylon and spandex yarns combined to be knit on each yarn feed to yield a fabric with a fiber content of 80% nylon and 20% spandex and a stretch characteristic of at least 80%, the front and back portions being joined by two side stretchable seams and having a hem, and an outer body portion having front and back portions to achieve a desired appearance, the inner body portion joined to the outer body portion along the top edges and the formed straps.
From the foregoing summary, it can be seen that the primary objective of the present invention is to provide a process for making and a garment made by the process for shaping a wearer's body while providing a fashionable appearance which is made as two separate garments (an inner body portion and an outer body portion).
The inner body portion is designed to provide shaping benefits for the wearer and is made from a fabric that has compression characteristics and is designed to fit snugly to the body and tuck into the wear's pants or skirt. This provides the shaping benefit and is not visible when observing the wearer because of the outer body portion design.
The outer body portion of the camisole is designed to meet the fashion needs of the wearer. It can be constructed of many types of fabric and in many different configurations. The fabric can be any warp knit solid fabric or any Raschel closed or open lace fabric. The outer body portion can be sleeved, sleeveless, tank top or strapless and completely covers the inner body portion. This makes it possible for the wearer to have the shaping benefits of the inner body portion without disclosing that she is wearing a double layered garment.
Thus there has been outlined the more important features of the invention in order that the detailed description that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. In that respect, before explaining at lest one embodiment of the invention in detail, it is to be understood that the invention is not limited in its arrangement of the components set forth in the following description and illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways.
It is also understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting in any respect. Those skilled in the art will appreciate that the concept upon which this disclosure is based may readily be utilized as a basis for designing other structures, methods and systems for carrying out the several purposes of this development. It is important that the claims be regarded as including such equivalent methods and products resulting therefrom that do not depart from the spirit and scope of the present invention. The application is neither intended to define the invention, which is measured by its claims, nor to limit its scope in any way.
Thus, the objects of the invention set forth above, along with the various features of novelty which characterize the invention, are noted with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific results obtained by its use, reference should be made to the following detailed specification taken in conjunction with accompanying drawings wherein like characters of reference designate like parts throughout the several views.
The drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification. They illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the shaping camisole garment forming a part of the present invention and formed by the use of the process also constituting a part of the present invention.
FIG. 2 is a back view of the shaping camisole shown in FIG. 1 .
FIG. 3 is a perspective view of the shaping camisole shown in FIGS. 1 and 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and particularly to FIG. 1 , a shaping camisole garment (“camisole”) shown generally as 10 has arm-receiving openings 12 , a top edge 14 and straps 16 defined therein. Camisole 10 is formed of an inner body portion 18 and an outer body portion 24 as shown in FIG. 3 .
Inner body portion 18 is designed to provide shaping benefits for the wearer, being made from a fabric that has compressive characteristics and designed to fit snuggly to the body and tuck into the wear's pants or skirt 19 . Thus outer body portion 24 completely covers inner body portion 18 .
Inner body portion 18 has front and back portions 20 , 22 formed from nylon and spandex yarns. These yarns are combined to be knit on each yarn feed of a multi-needle knitting machine such as a tricot warp knit machine to yield a fabric with a fiber content of 80% nylon and 20% spandex having a minimum stretch characteristic of at least 80%. This means that a measured length of unstretched fabric, for example 5 inches, must be stretchable to a length of at least 9 inches and must return to its original length when the pull force is released. In order to consistently attain these stretch characteristics, the nylon and spandex yarns are maintained at constant tension levels during knitting by the use of yarn tension devices.
Outer body portion 24 has front and back portions 26 , 28 formed from less compressive and preferably decorative fabric. It can be any warp knit solid fabric or any Raschel type closed or open lace fabric. Outer body portion 24 can be sleeved, sleeveless, tank top or strapless.
Front and back inner body portions 20 , 22 have vertical edges positioned in FIG. 3 under the front and back outer body portions adjacent vertical edges 40 , 42 . These seams are preferably sewn using a four needle flat seam which provides maximum stretch, maximum comfort for the wearer and the least visibility of the seam when viewed from the outside during wearing. Since this seam is flat in construction, it does not cut into the wear's skin during body stretching and twisting. It is also invisible under clothing (and similarly under outer body portion 24 ), since there is no thick area or bulge to show through and be seen from the outside.
Inner body portion 18 is preferably secured to outer body portion 24 by a four needle flatseam positioned along top edge 14 and arm-receiving openings 12 .
Fabric is produced and provided to the cutting and sewing operation on rolls. These rolls are spread in layers on a cutting table. A predetermined pattern is used to cut front inner body and back inner body portions 20 , 22 of inner body portion 18 and front outer body and back outer body portions 26 , 28 of outer body portion 24 . The patterns are placed on the layers of fabric and the fabric layers are cut around each pattern. All necessary cut pieces are now available to produce inner and outer body portions 18 , 24 .
To fully complete outer body portion 24 , needed lace or trim accessories are attached before inner and outer body portions 18 , 24 are joined.
A hem 44 is formed along he bottom edge of inner body portion 18 using a two needle cover stitch which holds he end of the cut fabric in place and eliminates the rolling that can occur if more traditional overhead seams are used to lock the fabric at the bottom of the grment.
From the preceding description, it can be seen that a shaping camisole and process for making have been provided that will meet all of the advantages of prior art devices and offer additional advantages not heretofore achievable. With respect to the foregoing invention, the optimum dimensional relationship to the parts of the invention including variations in size, materials, shape, form, function, and manner of operation, use and assembly are deemed readily apparent to those skilled in the art, and all equivalent relationships illustrated in the drawings and described in the specification are intended to be encompassed herein.
The foregoing is considered as illustrative only of the principles of the invention. Numerous modifications and changes will readily occur to those skilled in the art, and it is not desired to limit the invention to the exact construction and operation shown and described. All suitable modifications and equivalents that fall within the scope of the appended claims are deemed within the present inventive concept.
|
A method for manufacturing a shaping camisole and the article produced therefrom having an outer decorative portion and an inner knit tube made with elastomeric yarn to provide midsection support.
| 3
|
FIELD OF INVENTION
This invention concerns improvements in the processing of filaments of a particular copolymer, namely an ethylene terephthalate/hexahydroterephthalate copolymer of 80-86 mol % terephthalic acid/20-14 mol % hexahydroterephthalic acid components, whereby such filaments are provided with improved properties, especially their load-bearing tenacity, and the resulting filaments, e.g., in the form of tows and staple fiber cut therefrom.
BACKGROUND OF THE INVENTION
Synthetic polymer fiber is used in textile fabrics, and for other purposes. For textile fabrics, there are essentially two main fiber categories, namely continuous filament yarns and staple fiber, i.e. cut fiber. Large amounts of filaments are used in small bundles of filaments, without cutting, i.e. as continuous filament yarn, e.g. in hosiery, lingerie and many silk-like fabrics based on continuous filament yarns; the present invention is not concerned with these continuous filament yarns, but with staple fiber and its precursor tow, which are prepared by very different equipment, and which require entirely different handling considerations because of the large numbers of filaments that are handled. Staple fiber has been made by melt-spinning synthetic polymer into filaments, collecting very large numbers of these filaments into a tow, which usually contains many thousands of filaments and is generally of the order of several hundred thousand in total denier, and then subjecting the continuous tow to a drawing operation between a set of feed rolls and a set of draw rolls (operating at a higher speed) to increase the orientation in the filaments, sometimes with an annealing operation to increase the crystallinity, and often followed by crimping the filaments, before converting the tow to staple fiber, e.g. in a staple cutter. One of the advantages of staple fibers is that they are readily blended, particularly with natural fibers, such as cotton (often referred to as short staple) and/or with other synthetic fibers, to achieve the advantages derivable from blending, and this blending may occur before the staple cutter, or at another stage, depending on process convenience.
It has been particularly desirable to blend synthetic staple fiber with cotton, particularly to improve the durability and economics of the fabrics made from the blends with cotton, because such synthetic staple fibers have a high load-bearing tenacity.
Synthetic polyester fibers have been known and used commercially for several decades, having been first suggested by W. H. Carothers, U.S. Pat. No. 2,071,251, and then by Whinfield and Dickson, U.S. Pat. No. 2,465,319. Most of the polyester polymer that has been manufactured and used commercially has been poly(ethylene terephthalate), sometimes referred to as 2G-T. This polymer is often referred to as homopolymer. Commercial homopolymer is notoriously difficult to dye. Such homopolymer is mostly dyed with disperse dyestuffs at high temperatures under elevated pressures, which is a relatively expensive and inconvenient process (in contrast to processes for dyeing several other commercial fibers at atmospheric pressure, e.g. at the boil), and so there have been several suggestions for improving the dyeability of polyester yarns. For instance, Griffing and Remington, U.S. Pat. No. 3,018,272, suggested the use of cationic-dyeable polyesters. Such polyesters, consisting essentially of poly [ethylene terephthalate/5-(sodium sulfo) isophthalate] containing about 2 mol % isophthalate groups in the polymer chain (2G-T/SSI), have been used commercially as a basis for polyester yarns for some 20 years.
Although such polyester fibers have been very useful, it has long been desirable to provide alternative fibers, having the desirable characteristics of commercial polyester fibers accompanied by excellent dyeing properties.
Watson, in U.S. Pat. No. 3,385,831, suggested textile fibers of copolymers of polyethylene terephthalate/hexahydroterephthalate. These fibers showed a surprising combination of enhanced dyeability and good overall physical properties, including low shrinkage values. These copolymer fibers are rather unique, considering the unusually large molar amounts of comonomer (i.e. the hexahydroterephthalate units, HT) in comparison with other comonomers in polymers with ethylene terephthalate (2G-T). Despite the advantages on paper, however, Watson's fibers were not produced in commercial quantities. Some reasons are believed to be the relatively low strength and relatively high sensitivity to elevated temperatures of Watson's fibers. As indicated, several properties do get less desirable as the proportion of comonomer is increased, although the dyeability is correspondingly improved. The improved dyeability from higher proportions of HT comonomer would have been very desirable, if such problems could have been solved.
An object of the present invention is to improve the properties of Watson's type of fibers of copolymers containing ethylene terephthalate (2G-T) and ethylene hexahydroterephthalate (2G-HT) units.
BRIEF SUMMARY OF THE INVENTION
According to one aspect of the invention, there is provided a process for preparing a tow of crimped filaments of ethylene terephthalate/hexahydroterephthalate copolymer of 80-86 mol percent terephthalic acid/20-14 mol percent hexahydroterephthalic acid components, said filaments having high load-bearing capacity, including the steps of melt-spinning said copolymer into filaments, forming a tow from a multiplicity of said filaments, and subjecting said tow to 2 stages of drawing, followed by annealing, and then crimping, wherein the annealing step is carried out by a hot roll annealing with the rolls heated to a temperature of 140°- 175° C. The filaments are preferably relaxed 2-10% as they are advanced during the annealing step.
According to another aspect of the invention, the resulting filaments and cut fibers are also provided.
DETAILED DESCRIPTION OF THE INVENTION
The particular copolymers and many of the details of their preparation and processing into fibers are described in Watson, U.S. Pat. No. 3,385,831, the disclosure of which is hereby specifically incorporated by reference. However, according to the present invention, it has proved possible to improve the properties of the fibers sufficiently so that the molar proportion may be as high as about 20 mol % of the hexahydroterephthalate(HT) comonomer component, i.e. about 12-20 mol % may be used, about 16-18% being preferred, especially about 17%. It is most unusual to find a satisfactory polymer of such high comonomer content, and much of the art prescribes that the amount should not exceed 15 mol%. Indeed, as indicated, as little as 2 mol % is used commercially for the 2G-T/SSI fiber.
Preferred drawing and annealing conditions for conventional polyester filaments have been disclosed in the art, e.g. Vail U.S. Pat. No. 3,816,486, the disclosure of which is also hereby specifically incorporated by reference. Generally, the apparatus described and illustrated by Vail may be used to practice the present invention, subject to the comments herein. In particular, Vail's recommendations about temperatures should be modified, as noted herein. However, it should be noted that it is surprising that any hot roll annealing process should give such advantageous results to fibers of high comonomer content such as are described by Watson, in view of the very high shrinkages disclosed. Indeed, the annealing stage of the process of the present invention must be carried out between critical temperature limits, as indicated in the Examples, herein after. A slightly higher roll temperature, such as 180° C., has been found to render the process inoperable, whereas too low a temperature does not provide significant improvement.
The invention is further illustrated in the following Examples, and contrasted with the process taught by Watson, in Example 4, column 6, of U.S. Pat. No. 3,385,831. The temperatures mentioned for the annealing heat treatment were the temperatures of the electrically heated rolls. The fiber properties were measured on filaments from the crimped tow for convenience.
EXAMPLE 1
A random copolymer of 17 mol % polyethylene hexahydroterephthalate and 83 mol % polyethylene terephthalate was prepared by ester exchange and polycondensation reactions to a fiber grade molecular weight (Relative Viscosity =20.5 LRV; IV =0.63). The polymer was melt-spun in a conventional manner using a spinneret temperature of 275° C. and was wound up at 1000 ypm to give a yarn having 1054 filaments and a total denier of 3150.
Bundles of yarn were collected together to form a tow of approximately 56250 filaments which were processed to staple fibers with two stages of drawing, followed by an annealing heat treatment under tension using electrically heated rolls, crimping, drying, and cutting. (By way of comparison, Watson used a single stage of drawing followed by heat treatment under tension in an oven with an air temperature of 180° C. for 24 seconds.)
The fibers were passed through a series of feed rolls, then through water at 45° C., to a first series of draw rolls maintained at a peripheral speed of 55 ypm to give a first stage draw ratio of 3.21×. This was followed by a second stage of drawing at a draw ratio of 1.22×to give a total draw ratio of 3.93X. The tow was then sprayed with water at 75° C. to cool the tow. We found that, when we tried to use 90° C. water in either the bath or spray, this gave excessive filament breakage and caused filaments to wrap on the rolls, and also resulted in an unacceptable level of dark-dyeing defects in the product fiber.
The cooled drawn tow was then passed to a series of electrically heated rolls which annealed the filaments by heating them under tension. During heat treatment under tension, a maximum operable roll temperature of 175° C. was determined. A temperature of 180° C. for the rolls rendered the process inoperable. Total residence time in the heat treatment process was 8 seconds. Fibers were allowed to relax 10% during the annealing process. At 1% relaxation level, the process gave inoperably high tensions in the tow band, resulting in high motor loads and broken filaments. A fiber finish was applied to the fibers which were crimped using a stuffer box crimper to a level of approximately 9 crimps per inch. Steam at 6 psi was introduced into the crimper during this stage. The crimped fibers were dried in an oven at 105° C. with a residence time of 8 minutes. The fibers were cut to staple.
The crimped filaments (and staple fiber) had a crystallinity index of approximately 30, a tenacity (T) of 6.6 gpd, a break elongation of 12%, an intermediate tenacity at 7% elongation (T7) of 3.4 gpd, an initial modulus of 60 gpd, a DHS (dry heat shrinkage at 160° C.) of about 10% and a shrinkage in boiling (BOS) water of 2.5%. Fibers produced according to the invention had, surprisingly, a higher tenacity than in Example 4 of Watson, although the new fibers were more highly modified (higher copolymer level of 17%), annealed with rolls at a lower temperature (175° C.) for a shorter time (24 seconds), and crimped, all of which would have been expected to lower the fiber tenacity.
The new fibers had better resistance to alkali hydrolysis, losing only approximately 0.2% per minute in 5% sodium hydroxide [compared to the 18 mol % fibers described by Watson which had a higher loss rate, approximately 0.3%, in a lower caustic concentration, 3% NaOH].
EXAMPLE 2
The random copolymer described in Example 1 was prepared at an increased molecular weight to a relative viscosity of 24 LRV (IV approximately 0.72). The polymer was spun in a conventional matter using a spinneret temperature of 285° C. and was wound up at 1450 ypm to give a yarn having 900 filaments and a total denier of approximately 2950.
Bundles of yarn were collected together forming a tow of approximately 45000 filaments which were drawn in two stages, heat-treated at l75° C. using electrically heated rolls, crimped, dried, and cut essentially as in Example 1 (except as indicated in Table 1). The physical properties of the fibers produced using this process are also given in Table 1.
TABLE 1______________________________________ Anneal ShrinkTotal Temp T BOS Ten DensityDR (°C.) DPF (GPD) % E (%) (MGPD) (G/CC)______________________________________2.80 175 1.35 5.02 19.3 1.1 65 1.3703.00 175 1.30 5.77 15.6 1.0 81 1.3723.20 175 1.16 6.59 13.2 1.7 70 1.370______________________________________
All these new fibers had a higher tenacity than those described by Watson. The relative disperse dye rate (RDDR) of the annealed fibers is approximately 6.5 times that of standard homopolymer.
EXAMPLE 3
A polymer with the same relative ratios of polyethylene hexahydroterephthalate and polyethylene terephthalate with the addition of 0.005 lb./lb. (of polymer) of tetraethyl silicate viscosity booster was made to a relative viscosity of approximately 16 LRV (IV approximately 0.57). The polymer was melt-spun in a conventional manner using a spinneret temperature of 275° C. and was wound up at 1200 ypm to give a yarn having 1054 filaments and a total denier of 5250.
Bundles of fibers were collected together forming a tow of approximately 42150 filaments which were drawn in two stages, heat-treated under constant tension, crimped, dried, and cut using the process, again, essentially as described in Example 1. The properties of the fibers resulting from this process are given in Table 2.
TABLE 2______________________________________To- Annealtal Temp T T.sub.10 % BOS RDDR DyeDR (°C.) DPF (GPD) (GPD) E (%) (%) Rate______________________________________3.87 170 1.42 3.45 2.3 19.0 2.2 432 0.212______________________________________
The relative disperse dye uptake RDDR, (with carolid carrier) of the fiber produced by this process was compared to a standard polyethylene terephthalate control and was found to be 432 versus 100 for the control. The Dye Rate of the fiber was found to be 0.212 versus a rate of approximately 0.05 for a typical polyethylene terephthalate fiber.
EXAMPLE 4
The random copolymer described in Example 1 was prepared to a relative viscosity of 20.5 LRV (IV - 0.63). The polymer was melt-spun in a conventional manner using a spinneret temperature of 275° C. and was wound up at 1200 ypm to give a yarn having 1200 filaments and a denier of approximately 5250.
Bundles of yarn were collected together forming a tow which was drawn (as before) in two stages, heat-treated under constant tension, crimped, dried, and cut. The physical properties of fibers produced using this process are:
TABLE 3______________________________________ AnnealTotal Temp T T.sub.10 BOS RDDRDR (°C.) DPF (GPD) (GPD) % E (%) %______________________________________3.80 140 1.17 5.7 2.2 32.8 8.6 3354.01 140 1.09 6.6 3.3 22.7 9.1 3334.11 140 1.03 7.8 2.8 26.0 7.6 3203.56 160 1.22 5.5 3.6 27.0 4.8 2903.56 165 1.25 5.9 3.7 31.5 3.8 3713.56 170 1.23 6.6 4.0 31.3 4.0 3503.56 175 1.21 6.6 3.6 30.7 3.4 344______________________________________
These results show (as expected) that fiber tenacity generally increased with draw ratio. At the same draw ratio, fiber tenacity increased with annealer temperature. We found that an annealer temperature of 180° C. resulted in fiber fusion, adhering to other fibers and process equipment. A reduction in annealer temperature gave lower T 10 and higher boil-off shrinkage values.
|
Improved fibers of a copolymer of ethylene terephthalate/hexahydroterephthalate containing a high proportion of hexahydroterephthalate are obtained by a 2-stage drawing process, involving annealing, and crimping, with the annealing being performed within a temperature range of about 140° to about 175° C.
| 3
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a scanning display device for forming an image by two-dimensional scanning with a light beam, and more particularly to a scanning display device having a plurality of scanning surfaces. In addition, the present invention relates to a video image taking apparatus such as a digital still camera or a digital video camcorder, having the scanning display device serving as an electronic viewfinder.
[0003] 2. Related Background Art
[0004] An apparatus for recording an image obtained by an image pickup device represented by a charge-coupled device (CCD) includes a so-called digital stall camera (hereinafter referred to as a DSC) and a digital video camcorder (hereinafter referred to as a DVC). The DSC and the DVC each are generally provided with a finder for exhibiting an image taking area to a user.
[0005] For a large number of apparatuses, an optical view finder having a specific optical system is used as the finder in addition to an optical system for performing image pickup by a CCD or the like. However, in the case of such an optical view finder system using the optical system in addition to the optical system utilized for image pickup, there is a problem in that an image taking region observed through the finder is different from an image taking region of an image which is actually taken by a so-called parallax, in particular, in close-up image taking.
[0006] In contrast to this, there is an electronic viewfinder for displaying, as an image, a signal from the image pickup device such as the CCD on a display panel like a small size liquid crystal panel and enlarging the image for observation using an optical system. According to the electronic viewfinder, without being processed, the signal from the image pickup device is utilized. Therefore, an image having same view angle as that of the image, which is actually to be taken, can be observed, so that the image taking region can be determined with parallax error-free view.
[0007] An electronic viewfinder system using a scanning image display device as described in Japanese Patent Application Laid-Open No. H11-084291 has been proposed as an electronic viewfinder system in which a high-resolution image can be obtained. The scanning image display device is of a finder system which does not utilize a conventional display device such as a liquid crystal panel, and can obtain the high-resolution image. Because the liquid crystal panel or the like is not utilized as the display device, for example, a manufacturing problem such as the occurrence of a pixel defect is unlikely to cause.
[0008] On the other hand, for a large number of DSCs and DVCs, a direct-view display element having a size of several inches is provided on the side surface or rear surface of a main body in addition to a conventional near eye viewfinder. The direct-view display element is utilized instead of the viewfinder by displaying the signal from the image pickup device without being processed as in the electronic viewfinder. In this case, as compared with the conventional viewfinder, an effect such as an improvement of the degree of freedom of posture in image taking is obtained. The direct-view display element is also used to display an image taking condition, a battery level, the number of taken images, and the like. Therefore, an effect such as an improvement of convenience is large when the DSC or the DVC is used.
[0009] However, the direct-view display element has a defect that display is hard to be viewed in an environment of lighted surroundings such as the outdoors on a bright day. Therefore, the direct-view display element cannot always serve as the viewfinder.
[0010] Therefore, in the DSC and the DVC, in order that an image taking region is checked regardless of a state such as lighting of the surroundings and convenience that information including a current image taking condition is also displayed is ensured, it is preferable that the direct-view display element is provided on the side surface or rear surface in addition to the electronic view finder.
[0011] When the DSC or the DVC is provided with two display systems, that is, both the electronic viewfinder and the direct-view display element, it is necessary to provide at least two display devices such as liquid crystal panels. Therefore, a reduction in size and weight of an image taking apparatus becomes difficult, so that an increase in cost of the image taking apparatus occurs.
SUMMARY OF THE INVENTION
[0012] An object of the present invention is to provide a scanning image display device capable of performing display on a plurality of display screens by a single scanning display mechanism.
[0013] Another object of the present invention is to provide a video image taking apparatus which includes, for example, a near eye electronic view finder, which is to be looked through, and a direct-view display element provided on a side surface or rear surface and can utilize two display modes of the electronic view finder and the direct-view display element with a single scanning display mechanism and perform high resolution display.
[0014] To solve the above-mentioned problems, an image display device according to an example of the present invention includes: a light source; a scanner for two-dimensional scanning with light from the light source; and a controller which is electrically connected with the light source and the scanner and controls the light source and the scanner so as to form an image on the scanning surface, in which the scanner is configured to be capable of scanning plurality of scanning surfaces independent from each other with the light from the light source.
[0015] An image taking apparatus of the present invention according to an example of the present invention includes: an image taking optical system; a photoelectric transducer for receiving an image formed by the image taking optical system and converting the image into an electrical signal; and the above-mentioned image display device, in which the controller of the image display device controls the light source and the scanner based on the electrical signal from the photoelectric transducer so as to form the image on the scanning surfaces.
[0016] The image taking apparatus has an electronic viewfinder and a direct-view display element as display portions of the image display device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic structural diagram showing a scanning image display device according to Embodiment 1 of the present invention;
[0018] FIG. 2 shows an example of a two dimensional scanner using a deflection mirror device (MEMS scanner) for the scanning image display device;
[0019] FIGS. 3A and 3B are explanatory views showing a switching means of a scanning center of the deflection mirror device in Embodiment 1;
[0020] FIG. 4 is an example of an explanatory graph showing scanning amplitude of the deflection mirror device in Embodiment 1;
[0021] FIG. 5 is another example of an explanatory graph showing the scanning amplitude of the deflection mirror device in Embodiment 1;
[0022] FIGS. 6A and 6B are explanatory views showing a scanning method using the scanner in the scanning image display device;
[0023] FIG. 7 shows an example of the two dimensional scanner used for the scanning image display device;
[0024] FIG. 8 is a schematic structural diagram showing a scanning image display device according to Embodiment 2 of the present invention;
[0025] FIG. 9 is an example of an explanatory graph showing scanning amplitude of a deflection mirror device in Embodiment 2;
[0026] FIG. 10 is an explanatory view showing a scanning center switching means used for a scanning image display device according to Embodiment 3 of the present invention;
[0027] FIG. 11 is an explanatory graph related to a scanning amplitude of a deflection mirror device in Embodiment 3; and
[0028] FIG. 12 is a schematic structural diagram showing an image taking apparatus according to Embodiment 4 of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Hereinafter, a scanning image display device and a video image taking apparatus according to embodiments of the present invention will be specifically described.
Embodiment 1
[0030] Embodiment 1 of the present invention will be described with reference to FIG. 1 . FIG. 1 is a schematic diagram showing a scanning image display device according to Embodiment 1. A reflection mirror 13 bends an optical path of a light beam 12 emitted from a light source 11 and the light beam 12 is incident on a reflection scanner 14 . The light beam 12 incident on the reflection scanner 14 is scanned in two-dimensional directions by the scanner 14 . Gradation of the light beam 12 emitted from the light source 11 and an angle of the light beam 12 with which the scanning performed by the scanner 14 are controlled by a controller 113 electrically connected with the light source 11 and the scanner 14 (which may be wired connection or wireless connection). Therefore, it is possible to draw a predetermined image. When a plurality of light sources having different wavelengths are used for the light source 11 , full color image display can be achieved.
[0031] For example, a light source for generating laser light, such as a laser diode (semiconductor laser) can be used as the light source 11 . When an LED or a light source for generating general scattering light is used, it is effective to provide an optical system for converting light from the LED or the light source into a sufficiently slit beam.
[0032] As described later, in FIG. 1 , the scanner 14 can scan at least one of or both of an optical element composing an eyepiece optical system 15 and a back screen 18 having a diffusion plate characteristic through a predetermined optical system 111 .
[0033] In the case where an object scanned with the light beam 12 by the scanner 14 is changed, when all the objects to be scanned are included in a region which can be scanned by the scanner 14 , by selecting the scanning region of the scanner 14 by the controller 113 , it is possible to scan a plurality of objects to be scanned.
[0034] On the other hand, when a plurality of objects to be scanned are not included in the scanning region, the scanning region may be changed by a means for changing a mounted angle of the scanner 14 as described later.
[0035] For example, when a position of the reflection mirror 13 is changed without changing the scanning angle and mounted angle of the scanner 14 , the object to be scanned can be changed by changing an incident angle of the light beam 12 incident on the scanners 14 .
[0036] Further, the object to be scanned can be also changeable by switching the optical path of the light flux exited from the scanner 14 to a different direction, such as by using a polarization beam splitter for transmitting or reflecting light according to a selected polarization state of the light, or by disposing a reflection mirror on an exit optical path of the light flux exited from the scanner 14 whose mounted angle is changeable.
[0037] In this embodiment, the case where a plurality of objects to be scanned are scanned by selecting the scanning region of the scanner 14 by the controller 113 , in particular, when the plurality of objects to be scanned are included in the region which can be scanned by the scanner 14 will be described below.
[0038] In FIG. 1 , the scanning center of the scanner 14 is located at an angle θ 1 relative to the incident direction of the light beam 12 (hereinafter referred to as State 1 ) and is on a first optical axis 19 which is the optical axis of the eyepiece optical system 15 . When the optical element composing the eyepiece optical system 15 is scanned with the light beam 12 by the scanner 14 , the light beam 12 is incident on the eyepiece optical system 15 . Here, the region scanned with the light beam 12 depends on the scanning angle of the scanner 14 . By configuring the eyepiece optical system 15 such that a deflection original position of the scanner 14 is made conjugate with a pupil 16 of an observer, the scanned light beam 12 passes through at substantially one point of the pupil 16 of the observer, thereby drawing a desirable image on a retina 17 . Thus, by two-dimensionally scanned with the light beam 12 by the scanner 14 , a two-dimensional image is formed on the retina 17 .
[0039] On the other hand, the scanning center of the scanner 14 makes an angle θ 2 , which is different from the angle θ 1 in State 1 , with the incident direction of the light beam 12 (hereinafter referred to as State 2 ) and is on a second optical axis 110 for scanning the back screen 18 which is the direct-view display element. In this case, the back screen 18 is scanned with the light beam 12 through the projection optical system 111 by the scanner 14 . By using a transmission type diffusion plate having a light diffusion characteristic as the back screen 18 , a two-dimensional image is formed on the back screen 18 scanned with the light beam 12 in the two dimensional directions by the scanner 14 . Therefore, the observer 112 can observe the formed image.
[0040] A function for determining a region of the back screen 18 scanned by the scanner 14 , a function correcting distortion caused by a positional relationship between the scanner 14 and the back screen 18 , and the like can be provided for the projection optical system 111 .
[0041] In this embodiment, a deflection mirror device produced by a MEMS technique is used as an example of the scanner 14 . FIG. 2 is a schematic view showing the deflection mirror device. A deflection mirror device 24 is a mirror having a scanning function, which is produced by processing a Si substrate using the MEMS technique. A mirror 23 that reflects an incident light is held by two torsion bars 21 and 22 . The two torsion bars 21 and 22 are orthogonal to each other. A light beam which is incident on the scanner 14 is reflected on the mirror 23 . At this time, each of the two torsion bars 21 and 22 is twisted about a reflection surface of the mirror 23 by external force. Therefore, it is possible to change the orientation of the reflection surface of the mirror 23 , thereby scanning with the light beam incident on the mirror in the two-dimensional directions.
[0042] A mechanism for changing a stationary position of the scanner 14 will be described below as an example of a means for changing the object to be scanned of the scanner 14 . The scanning center can be switched between State 1 and State 2 by, for example, changing the stationary position of the mirror of the deflection mirror device which is an example of the scanner 14 .
[0043] FIGS. 3A and 3B schematically show the occurrence of vibration motion in the rotating direction of the mirror of the deflection mirror device and an example of a switching means for switching the stationary position (scanning center). As shown in FIGS. 3A and 3B , electrodes 31 and 32 are disposed near the mirror 23 at opposite positions. Note that FIGS. 3A and 3B show the case where the mirror is observed from a direction parallel to the torsion bar 21 . Similarly, even in the case where the mirror is observed from a direction parallel to the torsion bar 22 , electrodes 33 and 34 are disposed. A different voltage is applied to each of the electrodes 31 and 32 to generate electrostatic forces each having a different strength between the mirror 23 and the electrodes 31 and 32 . Therefore, the mirror 23 can be rotated about the torsion bar 21 . In this time, an electric potential of the mirror 23 is kept constant.
[0044] FIG. 3A shows a state of the deflection mirror device 24 in State 1 . The mirror 23 vibrates about a horizontal state as an origin in the rotating direction.
[0045] In the state shown in FIG. 3A , respective voltages applied to the electrodes 31 and 32 are expressed by the following expressions.
[0000] V 31=− A ( t ) Electrode 31
[0000] V 32= A ( t ) Electrode 32
[0046] When the voltages whose amplitudes are equal to each other and polarities are opposed to each other are applied to the electrodes, the mirror 23 is rotated about the torsion bar 21 to perform scanning with the incident light beam. Here, t denotes a time and A(t) denotes an applied voltage component periodically varied with the time t.
[0047] In contrast to the state shown in FIG. 3A , FIG. 3B shows a state of the deflection mirror device 24 in State 2 . The mirror 23 vibrates about a position shifted from a horizontal state as an origin in the rotating direction. For example, when a bias voltage is applied to only the electrode 32 , electrostatic force is generated on only one side of the mirror 23 as shown in FIG. 3B , thereby vibrating the mirror 23 about a tilt state thereof as an origin. Therefore, the state shown in FIG. 3B can be realized.
[0048] In the state shown in FIG. 3B , respective voltages applied to the electrodes 31 and 32 are expressed by the following expressions.
[0000] V 31=− A ( t ) Electrode 31
[0000] V 32= A ( t )+ V 1 Electrode 32
[0049] According to the above-mentioned voltage application, as shown in FIG. 3B , the mirror 23 vibrates about a state in which the mirror 23 is tilted as the scanning center. Therefore, it is possible to scan the object to be scanned different from that in State 1 with the incident light beam. Here, V 1 denotes a bias voltage applied to only the electrode 32 . Not only in the case where the bias voltage is applied to one of the electrodes but also in the case where a voltage having a different amplitude is applied to each of the electrodes, the scanning center can be adjusted.
[0050] Only the motion about the torsion bar 21 is described. The motion about the torsion bar 22 is similarly produced.
[0051] FIG. 4 is a schematic graph showing scanning characteristics of the scanner 14 . FIG. 4 shows, of the scanning characteristics of the scanner 14 , in particular, a scanning characteristic in a vertical direction in the case where a scanning direction used for switching the scanning center corresponds to a vertical direction of a reproduced image.
[0052] A line 41 is an example of a scanning characteristic of the scanner 14 in a vertical scanning direction. In FIG. 4 , the ordinate indicates swing angle and the abscissa indicates time. It is possible that the scanner 14 has, as the scanning characteristic in the vertical scanning direction, a saw-tooth scanning characteristic including a linear region as indicated by the line 41 . Scanning in the horizontal direction corresponding to a position at each swing angle is performed in a part that slopes upward to the right, of each of regions drawn by the line 41 in FIG. 4 as described below.
[0053] In this time, the scanner 14 can has scanning amplitude 46 in the vertical direction, however, in practice, a single object to be scanned is not necessarily scanned with the scanning amplitude indicated by 46 . A range with the scanning amplitude 46 can be divided into two regions, that is, a region 47 and 48 having a scanning center 45 and 43 , respectively, different from the scanning center 45 to perform scanning having a small scanning amplitude 44 and 42 , respectively. For example, the region 47 is assigned to an optical path toward the eyepiece optical system 15 in FIG. 1 and the region 48 is assigned to an optical path toward the direct-view display element 18 in FIG. 1 . Therefore, it is possible to switch between two display modes. According to the above-mentioned mechanism, for example, in order to reproduce SVGA (800 in width and 600 in height) images on both screens of the view finder and the direct-view display element, which are disposed vertically adjacent to each other, by scanning using the scanner 14 through the optical path toward the eyepiece optical system 15 and the optical path toward the direct-view display element 18 , the scanner 14 requires the scanning amplitude 46 of at least 1200 lines corresponding to two times of 600 lines. When the image is displayed on the view finder, a signal is inputted from the controller 113 to the scanner 14 such that the mirror of the scanner 14 vibrates only with 600 lines corresponding to the region (amplitude) 47 , of the scanning amplitude 46 of 1200 lines, thereby performing scanning. Scanning is not performed on the other region. When the image is displayed on the direct-view display element, a predetermined bias is added to the signal from the controller 113 such that the mirror vibrates only with 600 lines corresponding to the region (amplitude) 48 . Thus, the image can be reproduced on the plurality of screens in the signal scanning display device.
[0054] FIGS. 6A and 6B show a scanning method of performing scanning with the light beam 12 using the scanner 14 . In the scanning image display device according to this embodiment, an image is produced by scanning with a single beam in the longitudinal and lateral directions by the scanner 14 . Specifically, scanning is performed on a line in the horizontal direction and then scanning is performed on a line located below the line by one line. Such scanning is repeated to scan the entire screen. With respect to the horizontal scanning direction in this case, as shown in FIG. 6B , it is effective for drawing to reverse the scanning direction every line in view of a drawing speed. This case is compared with the case where scanning is performed by a scanning method corresponding to a type of an image generally produced by an image pickup device or the like as shown in FIG. 6A . As a result, it should be noted that image signals on a line ( 64 ) drawing hatched pixels, corresponding to a return route are treated as image data in a reverse direction to a line direction ( 63 ) of data produced by the image pickup device.
[0055] In this embodiment, the scanning characteristic in the vertical scanning direction, which is used for switching of the display means, is set to the saw-tooth drive characteristic including the linear region. The scanning characteristic may be set to a sinusoidal drive characteristic as shown in FIG. 5 . In this case, the scanner has a scanning characteristic indicated by reference numeral 51 and scanning amplitude indicated by reference numeral 56 . In the case of State 1 , drawing can be performed by vertical direction scanning having a scanning characteristic 52 , a scanning center 54 , and scanning amplitude 57 . In the case of State 2 , drawing can be performed by vertical direction scanning having a scanning characteristic 53 , a scanning center 55 , and scanning amplitude 58 .
[0056] In this embodiment, the example using the two-dimensional deflection mirror device capable of performing scanning in the two-dimensional directions by itself as the scanner is described. Even when a two-dimensional scanning unit 73 in which a deflection mirror device 71 capable of performing scanning only in a one-dimensional direction is combined with a scanning mirror 72 for performing vertical direction scanning is used as shown in FIG. 7 , the same effect can be obtained.
Embodiment 2
[0057] FIG. 8 is an explanatory diagram showing a scanning image display device according to Embodiment 2 of the present invention. The scanning image display device according to Embodiment 2 has substantially the same structure as in Embodiment 1. However, a switching means for the display means serving as the objects to be scanned by the scanner 14 in Embodiment 2 is different from that in Embodiment 1. Hereinafter, assume that members for which the same reference numerals as those used in Embodiment 1 are provided have the same functions. Therefore, the detail descriptions related to the members are omitted here.
[0058] FIG. 9 shows, of the scanning characteristics of the scanner 14 in. Embodiment 2, in particular, a scanning characteristic in the vertical direction. In Embodiment 1, in order to switch the display means, the object to be scanned by the scanner 14 is changed by changing the rotation and vibration range of the mirror 23 included in the scanner 14 . In contrast to this, in Embodiment 2, as shown in FIG. 9 , the scanner always performs reciprocation in a range 96 corresponding to the entire area which can be scanned in the vertical scanning direction. An optical path 97 for the viewfinder and an optical path 98 for the direct-view display element are arranged adjacent to each other in the longitudinal direction within the range 96 subjected to the reciprocation. Therefore, simultaneous display can be performed on both screens in the range (optical path) 97 corresponding to the near eye viewfinder and the range (optical path) 98 corresponding to the direct-view display element.
[0059] For example, when the resolution of the view finder and a back panel each is a resolution of SVGA (800×600), the scanner 14 having the scanning amplitude equal to or larger than 1200 lines is prepared. Here, it is possible that an image having 800 pixels×600 lines is displayed on the view finder by 600 lines corresponding to the range 97 and simultaneously the image having 800 pixels×600 lines is displayed on the direct-view display element by 600 lines corresponding to the range 98 .
[0060] On the other hand, when either one of the displays is performed, the light beam 12 is emitted from the light source 11 to only an area corresponding to a specified display portion. Therefore, it is possible to prevent drawing in an area other than the area corresponding to the specified display portion. Even in this case, the lens of the scanner 14 vibrates with the entire scanning amplitude corresponding to the range 96 , so that the control becomes easier.
[0061] Switching between the display on the viewfinder and the display on the direct-view display element may be automatically performed using a sensor 81 provided below the finder system. The sensor 81 is composed of a light source for emitting infrared light and a detector for detecting reflection infrared light. When an observer looks through the viewfinder, the infrared light from the light source is reflected on the face of the observer and the reflected light is detected by the detector. When the reflected light is detected, it is determined that the observer looks through the viewfinder. Therefore, an image is displayed on the electronic finder side. When the reflected light is not detected, it is determined that the observer does not look through the viewfinder. Therefore, the display mode is automatically switched to the direct-view display element side. Of course, the display mode may be manually switched.
[0062] As described above, according to the structure in this embodiment, it is possible to simultaneously display the image on two display means, that is, the viewfinder and the direct-view display element or display the image on either one of the two display means. However, in practice, the possibility that both the viewfinder system and the back panel are simultaneously observed is low. In addition, the simultaneous display causes an increase in electric power consumption. Therefore, it is desirable to display the image on either one of the two display means. For example, when the direct-view display element is intended to use while the viewfinder is used, it is desirable to perform display switching to eliminate the display on the viewfinder. Of course, the image may be simultaneously outputted to the two display means.
Embodiment 3
[0063] Embodiment 3 will be described with reference to FIG. 10 . In Embodiment 3, a manner of switching between two display methods by rotating the entire scanner 14 about the mirror deflection original point of the scanner will be described as a modified example of Embodiment 1. According to the mechanism, even when the scanner 14 having a small swing angle is used, scanning can be performed by switching between a plurality of objects to be scanned which are separated from one another in view of an angle. A structure other than a display method switching means is identical to that in Embodiment 1 and therefore the detail description related to the structure other than the switching means is omitted here.
[0064] FIG. 10 is an explanatory view showing a mechanism for changing the object to be scanned by the scanner 14 in this embodiment. As shown in FIG. 10 , the scanner 14 can be mechanically rotated about a rotating center 1005 of the deflection mirror 23 in the vertical scanning direction as an axis, that is, in a direction parallel to paper. According to the rotation of the scanner, the incident angle of the light beam 12 on the deflection mirror can be changed to switch the scanning range from a range 1004 a to a range 1004 b.
[0065] FIG. 11 is a graph showing a scanning characteristic in the vertical scanning direction in this embodiment. Scanning in the vertical scanning direction has a saw-tooth scanning characteristic including a linear region as indicated by reference numeral 1101 . In State 1 in Embodiment 1, scanning is performed in a range 1004 a with a scanning center 1102 . When the display method is switched (to State 2 in Embodiment 1), the scanning center is shifted from an initial center 1102 to a position 1103 , thereby performing scanning in a range 1004 b . Therefore, by rotating the entire scanner to shift the scanning center in each of States 1 and 2 , the display means can be switched.
Embodiment 4
[0066] In Embodiment 4, a video image taking apparatus using the scanning image display device described above will be described. FIG. 12 is a schematic diagram showing the video image taking apparatus according to the present invention.
[0067] In FIG. 12 , an image pickup optical system 101 forms images of a light beam from the outside on an image pickup element (photoelectric transducer) 102 . The image pickup element 102 converts the incident light beam into an electric signal and outputs the signal to a signal processing means 103 . The signal processing means 103 converts the input signal in a format suitable for a memory means 104 and a format suitable for the controller 113 of the scanning image display device. Then, the converted signals are outputted to the memory means 104 and the controller 113 . That is, the controller 113 and the signal processing means 103 are electrically connected with each other, thereby electrically connecting the controller 113 with the image pickup element 102 . Note that “the electrical connection” indicates that a state in which an electrical signal can be communicated between both regardless of wired connection or wireless connection.
[0068] According to the mechanism as described above, the controller 113 makes at least one of the view finder and the direct-view display element to display an image taken by the video image taking apparatus. Therefore, the image can be provided for the observer and the contents of the image can be checked. The memory means 104 records image by storing the signal from the signal processing means 103 in a magnetic tape or a memory composed of a semiconductor device.
[0069] As described above, in the scanning image display device for scanning with a light beam in the two-dimensional directions to display an image, it is possible to display the image on a plurality of locations by the signal scanner by providing a plurality of objects to be scanned by the scanner. When the scanning image display device is applied to the video image taking apparatus, for example, displaying on the viewfinder display and displaying on the direct-view display element located on the rear surface can be realized by single scanner. When switching between the two kinds of display methods is performed by the single device, it becomes possible to simplify a system structure.
[0070] This application claims priority from Japanese Patent Application No. 2003-342959 filed on Oct. 1, 2003, which is hereby incorporated by reference herein.
|
Disclosed is a scanning image display device for displaying an image on a plurality of display screens. The image display device includes a light source, a scanner for two-dimensionally scanning with light from the light source, and a controller which is electrically connected with the light source and the scanner. The controller controls the light source and the scanner to form an image on the surfaces to be scanned. The scanner is configured to be capable of scanning the independent plurality of scanning surfaces with the light from the light source.
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the invention
This invention relates to a method and apparatus for protecting and maintaining shorelines, and more particularly to such a device for growing aquatic vegetation in soil-filled, wave energy-absorbent pilings.
2. Discussion of the Background
Wave and current movements cause erosion and sedimentation where water transfers energy to shorelines. Typical methods of halting this process fall into two categories. Sheet piling and retaining wall methods place a barrier that reflects wave energy, by providing a vertical surface at the land/water interface. Riprap or revetment construction methods employ a sloped hard surface to achieve the same result. The construction elements used for the above methods are rarely in harmony with nature, as corrosion-resistant materials available are generally employed in their construction. These methods of construction have resulted in vast stretches of shoreline that have no natural interface where land and water meet, and which do not take advantage of energy-absorbing properties of natural materials. In addition, wave reflecting construction practices typically lead to greater erosion adjacent to them, where the energy has been redirected. There is a need therefore for a stabilization method that is wave energy- absorbing, natural, and can be integrated into a structural design sufficient to withstand strong water forces.
U.S. Pat. No. 5,178,489issued to Suhayda discloses a shoreline protection technique that incorporates used automobile tires into walls or baffles used to absorb wave energy, divert water, and trap sediment. According to Suhayda, the tires are anchored to a water body bottom via pilings 58. However, Suhayda fails to incorporate natural materials, and contributes to water pollution by submerging automobile tires into water.
U.S. Pat. No.5,338,131issued to Bestmann overcomes some of the problems associated with traditional methods of shoreline protection. Bestmann discloses a shoreline construction technique that incorporates precultivated, emergent aquatic plants whose roots are held within a water-permeable, biodegradeable vegetative carrier system, and other botanical elements to protect shorelines. However, according to Bestmann the botanical elements are anchored by varying methods of staking the elements into the shoreline, a labor intensive approach which provides limited wave energy resistance. For example, Bestmann discloses an aquatic plant 14 rooted in a plant plug 12 which is disposed in a substrate 31. However, substrate 31 is disposed flush with the existing shoreline, and horizontal at its upper end, thereby offering little or no wave energy absorption. The elements used by Bestmann, such as "layers of biodegradable non-woven felt" and "geotextiles" can be cost prohibitive for large projects. Furthermore, biodegradable felt is a temporary stabilization measure meant to retard erosion only until it has biodegraded, after which it provides no further stabilization properties. Using such materials and methods requires extensive regrading of the shoreline area to create a nearly flat shoreline, which is labor intensive and cause erosion in and of itself
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an arrangement for shoreline construction, maintenance and protection which incorporates ecological elements on or about structures, which allows the creation of habitat area on or about structures at the land/water interface.
Another object of the present invention is to provide an arrangement for shoreline construction, maintenance and protection which uses ecological elements placed on or about structures, which allows the use of the wave absorbing properties of natural materials on or about structures to reduce or prevent erosion.
Another object of the present invention is to provide an arrangement for shoreline construction, maintenance and protection which uses ecological elements placed on or about structures, which provides additional area for the growth of plants, which filter pollutants, and trap sediments.
Another object of the invention is to provide a method for the placement of ecological elements on or about shorelines in a manner that reduces or prevents erosion of the stratum in which the elements are placed.
Another object of the invention is to provide a low-cost method for the placement of ecological elements on or about shorelines in a manner that provides substantial wave energy absorption.
These and other objects are achieved by providing a tubular piling system including a plurality of closely stacked hollow pilings arranged along a shoreline wherein the pilings have a bottom portion embedded in the water body bottom and an upper portion protruding above the water body bottom such that the upper portion absorbs and transfers wave energy to the water body bottom via the bottom portion. The upper ends of the pilings are beveled to mimic natural stable slopes and incorporate plant materials to mimic natural habitat areas.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing, wherein:
FIG. 1 is a cross-sectional view of an embodiment for a planting area tube.
FIG. 2 is a perspective view of the embodiment shown in FIG. 1.
FIG. 3 is a plan view of a typical installation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIG. 1 thereof, FIG. 1 illustrates the construction of one embodiment of the arrangement for shoreline construction, maintenance, and protection according to this invention. In this embodiment, a plurality of pilings 1 are anchored into the water body bottom 2 adjacent the shoreline.
Each of the pilings 1 have upper end 10 and lower end 14, and are constructed of a corrosion resistant material, such as polyvinyl chloride (PVC), polyethylene, painted fiberglass, fiberglass reinforced plastic, stainless steel, ceramic, or teflon, however, PVC is widely available in various shapes, thicknesses, and strengths. Pilings 1 are preferably formed into tube or pipes with an inner diameter of4 to 12 inches and wall thickness of approximately 0.25 to 0.5 inches. Wider tubes would be more susceptible to erosion, as the soil plug is kept in place by friction between soil particles and the tube. Other cross sectional shapes such as rectangular, pentagonal, hexagonal or ovoid can be used, however, flat surfaces tend to reflect energy and corners are susceptible to increased scour if in direct contact with waves. An ovoid cross section would be acceptable, but is not currently mass produced. Pilings 1 with round cross sections are widely available, have equal energy transfer no matter which direction the wave energy comes from, and are therefor preferred.
Lower ends 14 of pilings 1 are anchored into water body bottom 2. Preferably, lower ends 14 are driven to a depth consistent with the anticipated wave energy to be absorbed by pilings 1. Typically, pilings 1 must be driven to a minimum depth equal to eight times the tube diameter, e.g. a six inch diameter piling 1 would be driven 48 inches into water body bottom 2. Upper ends 10 protrude a short distance above the water body bottom 2 adjacent the shoreline, typically upper ends 10 are either approximately flush or protrude above water body bottom 2 up to a height equal to the diameter of piling 1.
Pilings 1 are stacked a distance W outwardly from shoreline. Typically, distance W is 3.3 times the height difference D, rounded to the nearest piling diameter, where height D is equal to the difference in elevation between water body bottom 2 and stable soil 18. Once embedded into the bottom 2, pilings are filled with soil 4. Aquatic plants 3 are anchored into the soil 4 provided in the tube interior. Plants 3 vary according to the particular climate and anticipated water levels at the installation site.
Preferably, the height of soil 4 in pilings 1 is such that a cavity 12 is formed between the top of soil 4, an inner wall 22 of upper end 10, and an aperture 20 formed in upper end 10 of pilings 1. Cavity 12 is thus capable of trapping sediments from water body 7 and allowing uptake of a variety of substances by the plants. The cavity will have a cross section equal to that of the piling 1, and a height approximately equal to the diameter of piling 1. The level of soil 4 would be maintained by friction along the interior of pilings 1. As the diameter of piling 1 is increased, so does the mean distance from inner wall 22 to a particle of soil. Therefore, large diameter pilings 1 must be filled with clay soils, mid-sized diameter pilings 1 would function best with loamy soils, and small diameter pilings 1 would work best with sandy soils.
As illustrated in FIGS. 2 and 3 and as noted above, pilings 1 would preferably be installed in rows parallel to the shoreline, thereby creating a wall of width W between the water body 7 and the shoreline 6. It is possible to increase the rigidity of the resulting wall of pilings 1 by attaching interlocking joints (not shown) between pilings, however, this would significantly add to production and installation costs.
By constructing pilings 1 from material such as PVC pipe or tubing, pilings 1 would have only limited strength and wave energy absorption ability. However, by driving closely spaced pilings 1 into water bottom 2 and filling pilings 1 with soil 4, the strength and wave energy absorption ability of pilings 1 are supplemented by being buttressed by adjacent pilings, by soil 4 and partially by material from bottom 2 that fills lower end 14 of piling 1 during anchoring. By installing pilings 1 in such a way, the present invention effectively maximizes the use of natural materials such as soil 4 and bottom 2, in contrast to barriers made wholly of fabricated structures such as pilings and walls made of cement or steel. Furthermore, because of the shape of pilings 1 and the inherent flexibility of PVC, wave energy is effectively absorbed by piling 1, reflected upwards by beveled upper ends 10, and absorbed by plants 3, rather than being reflected to an opposite shoreline.
As shown in FIG. 2, The upper ends 10 of pilings 1 are preferably cut on a slant facing the water body 7 so that the resulting slope 16 of the upper ends of the pilings 1 matches the slope of a stable slope for the installation site. Stable slopes are sometimes formed in nature where the combination of angle of the slope and plant life growing on the slope result in a shoreline that can withstand wave energy without erosion. A slope that rises 0.33 feet per foot of lateral extension, or a slope of approximately 18 degrees, is an accepted stable slope condition under known engineering standards. With pilings 1 cut and arranged in such a way as to mimic a stable slope with angle S being approximately 18 degrees, pilings 1 take advantage of the geometry best suited for wave energy absorption, while minimizing the width W of the piling arrangement, and thereby minimizing the cost of the apparatus. Furthermore, the sloped arrangement of pilings 1 and plants 3 simulates a natural habitat, and encourages wildlife to utilize the habitat.
Alternatively, some of upper ends 10 of pilings 1 may be positioned so that cavity 12 faces the shoreline, thereby forming better protected habitat sites. Another advantage gained by facing at least some of cavities 12 toward the shore line is that sediments are better trapped in cavities 12 as water recedes from the shoreline.
The method for making and using the invention includes a pile anchoring step, a pile filling step, and a planting step. During the pile anchoring step, pilings 1 are anchored into the water body bottom 2, by partially burying them, or preferably, pile driving. In the anchoring step, pilings are arranged substantially as shown in FIG. 3. To protect upper ends 10 of pilings 1 during pile driving, pilings 1 may be fitted with a removable protective hood (not shown) that includes a main boss, an inner sleeve and an outer sleeve, arranged to sandwich the wall of upper ends 10 of pilings 1, and uniformly contact the upper edge of upper ends 10. Constructed as such, the protective hood would evenly distribute the impact shock of the pile driver, thereby avoiding damage to pilings 1 during pile driving.
In the pile filling step, pilings 1 are filled with soil 4, where soil 4 is chosen according to the particular climate, anticipated water levels and the type of aquatic plants 3 to be planted in soil 4. In the planting step, plants 3 are planted in soil 4, where plants 3 are chosen according to the particular climate and anticipated water levels.
Obviously, numerous additional modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein.
|
An arrangement for shoreline construction, maintenance, and protection, and methods for making and using the same wherein wave energy-absorbent pilings are arranged in rows parallel to a shoreline such that a portion of the pilings are exposed above the water body bottom and filled with soil, thereby absorbing and transferring wave energy to the water body bottom, and where aquatic vegetation is provided in the soil in the pilings resulting in a shoreline that is stable, incorporates natural materials and provides a habitat for aquatic life.
| 4
|
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/782,625 filed Mar. 14, 2013. The foregoing prior application is hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
(Not Applicable)
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
(Not Applicable)
REFERENCE TO AN APPENDIX
(Not Applicable)
BACKGROUND OF THE INVENTION
The invention relates broadly to structures used to keep debris from gutters, and more particularly to a structure for preventing leaves from entering into gutters.
Rain gutters (also known as eavestroughs or, gutters) are narrow channels or troughs that collect and divert water flowing off of a roof. Gutters have been disposed at roof edges for centuries to catch precipitation and either redirect it to a storage vessel, such as an underground cistern, or away from the foundation of the building to prevent the precipitation from damaging the building to which the gutters are attached. Conventional gutters mount to a face of the building, such as a soffit fascia, with the lip of the rear edge of the gutter just under the drip edge of the building's roof. When water runs down the roof, it falls under the force of gravity into the gutter, collects in pools and flows by gravity out of the inclined gutter into a vertical downspout. The downspout carries the water to a storage vessel or away from the foundation of the building.
Solid particles that fall onto roofs also fall into uncovered gutters. For example, sticks, leaves, seeds, needles and other particles fall onto roofs, typically from overhanging trees, and then roll or slide into gutters. Smaller particles in small quantities can be carried by rain water out of gutters and are harmless, other than when they deteriorate in cisterns and cause spoilage. However, sticks and larger particles, or small particles in larger quantities, cannot be carried away by the water flowing in a gutter. Such sticks and particles collect together to form a barricade, and then smaller particles are filtered by the debris to block the satisfactory flow of water from the gutter into the downspout. The water then collects in the gutter and creates a sanitary hazard and/or overflows, thereby damaging the building and gutter and defeating the purpose of the gutter system.
There are numerous systems for preventing, or reducing, the infiltration of particles into the open tops of gutters. These are placed over gutters to keep water flowing instead of being clogged by leaves and debris. These systems include porous, filtering materials, such as expanded metal and polymer screens, along with solid “caps” that drive solid particles over the cap while depending on the surface tension of water to flow over the cap and gutter and around a solid panel into the gutter. Brush-like structures have also been placed in gutters, and coiled, spring-shaped wire structures have been placed in gutters to extend along the length of the gutter. One problem with the coil apparatus is that leaves and other debris that are low-hanging through the wires cannot clear the far edge of the gutter as they move downhill and they catch the far edge of the gutter. The surface tension method using a sheet-type cap over the gutter appears to be the best at self-clearing, but it can cause a mold slime-like formation in the darkened gutter.
The prior art of which the inventor is aware provides advantages over an open-top gutter, but also disadvantages. To applicant's knowledge, all prior art fails to provide sufficient certainty that debris will neither clog the gutter nor the filtering apparatus. Therefore, the need exists for a method and means for keeping gutters clear of leaves and other debris while allowing sunlight and airflow into the gutter, which reduces mold and slime buildup on the filter and gutter.
BRIEF SUMMARY OF THE INVENTION
The invention contemplates a means to bridge over a gutter to allow leaves and other debris to slide off the roof, across the bridging structure above the gutter, and onto the ground without dropping into or catching onto, the gutter or filter. This is accomplished with a novel bridging structure that is described herein and shown in the illustrations. The structure has a plurality of rods aligned parallel to and along the downward sliding direction of the leaves and other debris. These rods are positioned substantially parallel and as close to one another as possible to prevent significant debris from falling into the gutter between the rods while still allowing the water to pass through into the gutter through the openings between the rods.
Except for very small particulate, the apparatus prevents most or all debris that comes into contact with a roof from entering the gutter, while still allowing rain and other liquid and small particulate to be carried away in a desirable manner by the gutter and downspouts. The apparatus also allows wind to blow up through the gutter filter to dislodge leaves and other debris, as well as dry out the gutter by the sun penetrating through the aligned rods of the apparatus.
The apparatus is referred to herein as a gutter leaf slide bridge (GLSB). The GLSB is designed so that the water and small quantities of very small particles that constitute non-clogging debris fall into the gutter, and larger debris, such as leaves, sticks and large seeds, roll or slide across the GLSB beyond the outside edge of the gutter and fall to the ground. The GLSB allows sunlight and air movement through the gutters beneath it, thereby preventing a slimy mold buildup in the gutter found with many systems that enclose the gutter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a side schematic view illustrating an embodiment of the present invention.
FIG. 2 is a side schematic view illustrating an alternative embodiment of the present invention.
FIG. 3 is a top schematic view illustrating a mechanism for forming a portion of the present invention.
FIG. 4 is a side schematic view illustrating an alternative embodiment of the present invention.
FIG. 5 is a side schematic view illustrating an alternative embodiment of the present invention.
FIG. 6 is a side schematic view illustrating an alternative embodiment of the present invention.
FIG. 7 is a side view in section illustrating a fastener portion for the present invention.
FIG. 8 is a side schematic view illustrating an alternative embodiment of the present invention.
FIG. 9 is a schematic view in perspective illustrating an alternative embodiment of a portion of the present invention.
FIG. 10 is a side schematic view illustrating an alternative embodiment of the present invention.
FIG. 11 is a front schematic view illustrating the embodiment of FIG. 1 .
FIG. 12 is a front schematic view illustrating an alternative embodiment of the present invention.
FIG. 13 is a magnified schematic view illustrating the embodiment of FIG. 12 .
In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific term so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected or terms similar thereto are often used. They are not limited to direct connection, but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.
DETAILED DESCRIPTION OF THE INVENTION
U.S. Provisional Application No. 61/782,625 filed Mar. 14, 2013 is hereby incorporated in this application by reference.
In an embodiment shown in FIGS. 1 and 11 , the GLSB 10 uses substantially parallel, spaced rod members 12 to form the bridge that supports the debris as it is carried across the upwardly facing opening of the gutter 14 to the far edge 14 f of the gutter 14 . The rod members 12 can be made of any metal, such as steel or aluminum, or plastic, polymer-reinforced composites or any other suitable material. The rod members 12 preferably range in diameter from about 0.03 to about 0.06 inches. The rods should be of minimum diameter possible and the sizes listed can be combined with larger rods or smaller rods. Of course, other diameters are contemplated if they are sufficiently strong and otherwise suitable. The rods are a length that allows them to span the distance across the gutter 14 that is required to carry and support debris over the gutter 14 . As an example, for a conventional piece of five inch wide aluminum gutter, the rod member 12 is a length that permits it to overhang the far edge 14 f by about one-half to one and one-half inches. Therefore, useful rods could be six to seven inches long, depending on how and where the rods are attached to the building or gutter.
The rods are preferably spaced laterally from each next adjacent rod to form a gap therebetween of about one-quarter of an inch or less, but this distance can be modified as will become apparent to the person of ordinary skill. Each rod member 12 is preferably aligned substantially perpendicular to the gutter's longitudinal axis, although a small angle is possible as will become apparent from the description herein. When aligned substantially perpendicular to the gutter's longitudinal axis, the rod members 12 are aligned with their longitudinal axis substantially along the direction debris and water flow down the roof 20 when under the influence of gravity. That is, the rod members 12 are substantially parallel, or only slightly transverse, to the direction water and debris flow down the roof 20 under the influence of gravity (wind and other effects may vary the direction). The rods are also substantially parallel to one another. This configuration allows the rod members 12 to provide as little resistance to continued flow of debris over the gutter, while allowing water to flow between the rod members 12 into the gutter with little resistance. In order to maintain the rods parallel to one another, the rods themselves preferably have a spring effect that is substantial enough that if a rod is bent to one side, upon release it returns substantially to its original position. This “spring effect” can arise by using spring steel, for example.
Each rod member 12 can be mounted at the gutter 14 near the inner edge of the gutter 14 i . The rod members 12 extend from or near the roof's edge 20 e in cantilevered fashion above and beyond the far edge 14 f of the gutter 14 , as shown in FIGS. 1 and 11 . A vertical gap, g, is formed between the top surface of the far edge 14 f of the gutter and the lower surfaces of each of the rod members 12 . The vertical gap, g, is to allow leaves and leaf-like debris that have portions (stems, thorns, etc.) that may extend downwardly through the gaps between the rods to flow to the ends of the rods without resistance, such as from catching on the gutter's far edge, as the debris slides down the parallel rod members 12 . The vertical gap between the far ends of the rods and the top of the gutter allows leaves and other debris that are low-hanging between and beneath the rods to slide past the end of the gutter as they move downhill along the rods, and not catch thereon.
The rod members 12 are substantially parallel and form a “comb-like” structure over the gutter 14 with the “teeth” of the “comb” being formed by the rod members 12 . A spine or frame 12 f , to which the rods mount, is substantially perpendicular to the rods and attaches uphill of the gutter 14 . The rod members 12 are cantilevered to as far beyond the far edge 14 f of the gutter 14 as is necessary to assure most or all debris completely bypasses the gutter 14 and falls away from the gutter. The back or “spine” of the “comb” preferably attaches to the house structure 30 , roof edge 20 e , or inner edge 14 i of the gutter 14 , but the frame 12 f can simply rest upon the surface of the roof 20 . The rods 12 are preferably angled substantially parallel, or slightly transverse, to the roof 20 , so that a generally downhill slope results. The frame can be integrated into the lower edge 20 e of the roof 20 , such as by inserting rods into spaced apertures disposed along a half-round piece of plastic, wood or metal that is attached at the lower edge of the roof, within the thickness of the lower edge 20 e.
In one embodiment contemplated, the frame of the “comb” is integral to the gutter's inner edge 14 i , having been mounted there during manufacture of the gutter. In another embodiment contemplated, rubber or other flexible roofing sheet material that is self-adhesive is adhered to the roof and over the frame of the comb-shaped structure to direct water falling down the roof over the frame of the comb. The rods can extend through apertures formed in the rubber sheet so that the sheet extends beneath the rods a short distance after passing over the frame and toward the roof edge 20 e . The rods cantilever above the gutter's far edge.
The rods' lengths can be a few inches to about a foot or even more depending on whether the rear attachment point of the rods is at the back of the gutter or on the roof. Thus, the rods preferably extend from just above and just beyond the far edge 14 f of the gutter to as far back toward or on the roof 20 as is necessary to reach the desired mounting or resting point of the frame. The rods 12 are sloped downward from the rear attachment point at the frame to the far edge 14 f of the gutter 14 to form a self-clearing leaf slide that guides leaves and leaf-like debris along a continuously sloped structure away from the sloped roof, onto the sloped rods and then off of the rods to the ground or a container for collection.
One type of GLSB uses short lengths of rods attached to a frame formed from a pipe 150 or round drill stock, as shown in FIG. 2 . The pipe 150 is attached above the rear edge 114 i of the gutter 114 with u-bolts (not visible) or a novel snap-in fastening device that allows the pipe 150 to pivot within the u-bolts or other fastener in the manner of a hinge. This pivoting is along an angle of about 30 to 90 degrees to an “up position” (see dashed lines in FIG. 2 ) from the rods' 112 operable location above the front gutter edge 114 f . The pivoting allows access to the inside of the gutter 114 for periodic cleaning or other maintenance. As noted above, the pipe 150 can be mounted to a structure that is deliberately formed in the gutter during manufacture of the gutter (see FIG. 6 ), or the pipe 150 can be retro-fitted, or the pipe can be mounted to the house's roof 120 or fascia.
One advantage of the pipe 150 structure shown in FIG. 2 is that the water tends to be driven downwardly, perpendicular to the rods 112 . As the water flows off the roof 120 it immediately flows along the curved surface of the pipe 150 , which is substantially perpendicular to the rods 112 at the intersection of the rods 112 with the pipe 150 . By directing the flow of water perpendicular to the rods at the intersection, this configuration reduces the probability that the water will cling by surface tension to the rods 112 and flow off the ends of the rods rather than fall into the gutter 114 . Thus, when the pipe 150 forms an approximately ninety-degree angle with the rods 112 at their intersection, there is a substantial structural and functional advantage.
Another GLSB is made from a wire mat 200 , as shown in FIG. 3 . The mat 200 can be about one foot wide, and is made by bending one strand of wire 202 back and forth around a die that consists of a plurality of dowels 204 or other prepared, solid structures at each side to form parallel wires that serve as the rods spaced about one quarter inch apart (see FIG. 3 ). Once the wire 202 is wound through and around the dowels 204 , the dowels are moved apart by force to remove any slack in the wire 202 and form the final length of the rods. The curved portions at the ends of each pair of rods can be cut off, or they can be retained and bent downwardly and inwardly to allow the debris to clear the curved ends as it falls off the rods, and also direct water into the gutter using surface tension on the rods. In this case the downwardly bent portions may not touch the gutter, but form a barrier to prevent larger rodents and other creatures from entering the gutter. The curved portions can be bent downwardly and inwardly to form a support leg that rests upon the far edge of the gutter as described herein, which also provides a barrier for pests.
As shown in FIG. 4 , one side of the mat 200 so formed is attached to the roof 220 (such as by a screw 210 extending through the roof side curved portions) and the other side of the mat 200 cantilevers above the far edge 214 f of the gutter 214 . The vertical gap, g 2 , formed between the front gutter edge 214 f and the underside of the mat 200 can be maintained by forming support structures at periodic intervals along the mat's length using parts of the mat formed. For example, during manufacture of the wire mat 200 , some of the wire 202 can be bent toward the gutter to form spaced “legs” 240 under the mat 200 that rest on the far edge 214 f of the gutter (see FIG. 5 ). These legs are spaced supports that contact the gutter 214 and space the gutter 214 from the mat 200 . A continuous GLSB can be made using this configuration because the top surfaces of the rods extend past the far edge of the gutter.
The mat 200 can be bent in its long direction along the roof to fit into a valley formed between two intersecting and transverse roof sections. A rubber roofing material can be adhered over the uppermost portion of the mat and the roof in order to force water and debris onto the top of the mat. Such a configuration permits the mat to carry debris out of the valley where it would otherwise collect, but water is permitted to flow through the rods to the gutter. Preferably, the lower ends of the rods extend over the far edge of the intersecting gutters' corner (or any vertical shield that is mounted to the gutter lip at this corner to direct the large volume of water from the valley into the gutter) in order to bridge entirely over the gutter.
By using wire stock from a large spool of wire at the job site, a mat can be formed on-site of desired width, wire spacing and length using special wire-forming equipment made for this purpose. As the wire (about one-sixteenth inch diameter) comes off the reel it is work-hardened and made straight. Next it is placed in a flat die having dowels at each end of the mat's width to wrap around and form the wire spacing of the rods. The dowels at each end are pulled apart for forming the final length of the mat (see FIG. 3 ). The flat mat formed is cut into lengths, for example three feet long. Then the mat can be bent to curve the mat for each field need of gutter width and height to roof relationship. A gap can be formed between the far edge of the gutter and the wire mat bridge. Also a cantilever (ideal) mat can be formed by attaching a bent mat to the roof and cutting off the opposite end to form separate rods 212 as shown in the illustration of FIG. 4 .
In one embodiment, the invention is formed in units of a specific length, such as three feet, and each unit is attached to other units in series. The attached collection of units is mounted along the gutter's length. The length of each unit of the apparatus (as measured along the gutter's length) can be on the order of a few feet for ease of installation of each unit. Alternatively, the apparatus can be constructed to be continuous along the length of the gutter in some embodiments so that there are no connectors or weaknesses that might be present in a series of connected units that depend on the installer's skill in connecting them.
The invention can take the form of a “comb” with the “teeth” being the rods, rails or bridging components and the transverse spine being a frame to which the rods mount. Alternatively, the invention can be in the form of disks with spacers like a large diameter washer spaced with a smaller diameter washer. Alternatively, a broom-like device can be used with the broom straws acting as the bridge over the gutter, and the straws cantilevering above the ends of gutter the same as the comb teeth forming a gap.
As the parallel rods are made closer and closer together, this decreasing gap improves the action of sieving debris. However, the closer the rods are together the more likely capillary action will occur, which could cause some of the water to cling to, and flow along, the rods past the far edge of the gutter, thereby defeating the purpose of the gutter. The surface tension of the water and its velocity direction as it comes off the roof or rod-holding device can be in the direction of the rods. This problem can be reduced or eliminated by using finer and flatter rods. Another solution is to form sawtooth-shaped (when viewed from the side) and/or v-shaped (when viewed from the end) profiles on the bottoms of the rods that cause the water to have a smaller surface to cling to so it drops off into the gutter before reaching the ends of the rods.
An alternative solution can be obtained by placing the rods at an angle to the water direction coming off the roof, and another uses the surface tension of the water clinging to a sheet that the rods pass through to drop the water below the rods. For example, if a rubber sheet is adhered at its top edge to the roof and extends a short distance down the roof to cover the frame of the rods, the rods of the invention can pierce the sheet, which causes the rods to extend transversely (at an angle to the sheet) beyond the sheet's point of attachment to the roof. The sheet thus extends from above the rods to below the rods with the rods extending through the sheet. This configuration creates a flow path for water to flow onto the sheet from the roof, down the sheet and through the rods by clinging to the sheet due to surface tension. In this configuration, the water follows the sheet down through the rods, rather than following the rods at an angle to the sheet.
Shorter rods could be passed under and between the main rods 12 , 112 and 212 that carry off the leaves, and the shorter rods (which do not have to be as long as the main rods) cause the water on the bottoms of the main rods to be more likely to fall into the gutter, rather than be carried over the ends of the main rods and past the gutter. Such shorter rods could also help support the upper rods that cantilever over the far, outer edge of the gutter. Additionally, smaller diameter (e.g., one-thirty second of an inch) or shorter (or both) rods can be alternated with the preferred main rods (e.g., one sixteenth of an inch diameter) described herein to help carry smaller debris and thereby reduce the amount of matter that can hang down between the rods as the matter passes over the far lip of the gutter. This is illustrated in FIGS. 12 and 13 , in which the main rods 612 a are twice the diameter and long enough to reach past the far edge of the gutter, and the smaller diameter rods 612 b are substantially the same length, but half the diameter. The smaller diameter rods 612 b can be shorter, and preferably do not carry substantial weight of larger debris that falls onto the main rods 612 a . Instead, the row of smaller diameter rods 612 b filter the smaller debris that falls past the larger main rods 612 a , and, because they are smaller diameter, the rods 612 b promote water falling into the gutter 614 , rather than flowing past the gutter's far edge. Furthermore, the smaller diameter rods 612 b may be shorter than the gutter's width, so that even if water flows to their ends and then drops, the water falls into the gutter 614 . If a second row of smaller diameter rods is placed beneath the row of larger diameter rods, the gaps between the smaller rods can be smaller than the gaps between the larger rods.
If metal sheeting is used to hold the rods, the sheeting could be formed to have rods and bring the water into the gutter. This could also be done as a plastic or metal molding and look much like a hair comb with its teeth hanging out over the end of the gutter and the spine of the comb (above the teeth) attached to the roof above the gutter.
In order to test the embodiments discussed above, a work table was made to hold a roof section having a gutter section at the low end and a water flow device at the high end. The roof section can be held at different slopes and different type roofing was placed on the table and different flow rates were selected. Leaves and roof debris was placed between the water source and the gutter on the roof section and the results were observed under closely controlled conditions.
The testing work supports the efficacy of the embodiments described herein. Most of the testing used one-sixteenth inch diameter rods and flat rods turned on edge (thinnest edges up and larger surfaces facing the next-adjacent rod). The testing showed that holding the rods parallel to one another is very important. The rods need to spring back to their original positions if they are deformed downwardly against the far edge of the gutter or laterally to a non-parallel relation. Furthermore, the capillary attraction of water to and between the rods increased as the rods were moved closer together and increased as the diameter of the rods increased.
The GLSB method and structures described herein show promise, because during testing the GLSB embodiments cleared a range of debris made up of small and large leaves, seed pods, twigs, and pine needles with a minimum of small debris going into the gutter. The amount that went into the gutter was cleared by normal flow of water in the gutter to the down spout. GLSB rods can be incorporated into a gutter so that the rods are manufactured along with the gutter and the two are integral. Different climate locations and debris types could call for different solutions to reduce cost and maintenance.
Applicant's studies show the cantilevered ends of the GLSB rods allow the debris to clear the end of the gutter. However, when the lower edges of the distal ends of the rods are held against the upper, outer edge of the gutter, leaves and debris are held back and do not slide off the ends of the rods. The studies thus far show that the slide made of thin rods perpendicular to the gutter's length and held above the outside edge of the gutter work better than the surface tension leaf rejection method that is conventional.
The water was brought below the rods of some embodiments by having the rods pass through metal or plastic sheeting as described above. The rods of other embodiments have been attached through plastic piping (having a one inch diameter and a one-eighth inch wall) and in others into one-quarter inch diameter solid rod stock. The sheeting can be part of the drip edge on the roof's edge, the sheeting can be part of the one inch diameter pipe between the drip edge and the gutter, and the sheeting can be part of the one-quarter inch rod on the roof itself.
Both the one inch diameter piping and the one-quarter inch solid rod can be mounted using a fastener that forms a hinge means for pivoting the GLSB rods to access the gutter for cleaning. This can be by rotating the pipe or rod to lift the GLSB rods. Stops can be put on the pipe or holding rod to define the maximum down and/or up position.
Rods can be formed by cutting a sheet along spaced, parallel lines and twisting the formed flat segments 90 degrees. Although this is an inexpensive method for forming GLSB rods, there can be problems with water attraction (capillary action) and holding the rods parallel.
The method of attaching the rods (teeth) to the back of the gutter, when the “comb” design is being used, will now be described in detail. For a new gutter system using GLSB or for a flat, high-back gutter already in use, a holding device 360 can be attached to the upper part of the back edge of the gutter 314 that allows the GLSB to be snapped in place, moved up or taken off easily, as shown in FIG. 6 . The holding device 360 can be molded out of plastic or metal that is attached to a conventional gutter 314 , or the holding device 360 can be extruded as part of a plastic gutter. In the illustrations of FIGS. 7 and 8 , the pivot structure 400 defines a C-shaped opening 402 for the cylindrical frame 408 of the comb-shaped device 412 to snap into. The lower tip 404 of the “C” provides a limit for downward movement of the rods of the device 412 , because the rods will rest against the lower tip 404 and maintain the vertical spacing between the rods and the far edge of the gutter. In order for the rods to move any lower, they must be bent. However, the rods can be lifted upwardly for cleaning as shown in FIG. 8 in dashed lines.
As shown in FIG. 8 , the frame 408 of the comb-shaped structure 412 is mounted in the holding device 400 in such a way (such as a friction fit) that pivoting up or down is possible when a sufficient force is applied. However, it is preferred that downward pivoting does not occur without deliberately moving the rods, in order to maintain the space between the lip of the gutter 414 and the bottom of the rods. As shown in FIG. 9 , the comb can be molded or made from wire 500 attached to a dowel 502 , and that dowel 502 can serve as a frame and be inserted in the holding device 400 as shown above, with the wire 500 serving as the rods.
As shown in FIG. 9 , the wire 500 has curved ends 504 that join adjacent pairs of wire. This means that any large debris sliding down the wires can catch in the curved ends 504 and not fall off the structure. It is preferred to either cut the curved ends off back to the straight portions of the wire 500 , or bend the curved ends downward toward the gutter (not visible) and back to allow the debris to clear the curved ends. The curved ends can form legs that support the wire 500 at the far edge of the gutter when the wire contacts the far edge of the gutter.
This detailed description in connection with the drawings is intended principally as a description of the presently preferred embodiments of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. The description sets forth the designs, functions, means, and methods of implementing the invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and features may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention and that various modifications may be adopted without departing from the invention or scope of the following claims.
|
A gutter protecting apparatus includes a plurality of substantially parallel rods extending in a downward slope from near a roof edge to and beyond the far side of the gutter. The rods extend substantially perpendicular to the gutter's length and to a frame to which the rods connect at the upper edge. Preferably, the lower rod ends are spaced above and slightly beyond the far edge of the gutter to allow debris to pass the gutter without catching. Legs can extend down from some rods to the gutter's far edge to provide support. The apparatus can be pivotably mounted to the roof, the fascia or the gutter, permitting access beneath. The apparatus forms a cage-like covering over the gutter to exclude matter and small creatures, while allowing the liquid to flow past. Sunlight bypassing the rods and movement of air through the gutter make the water exiting the downspout cleaner.
| 4
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is the National Stage of International Application No. PCT/KR2009/006810, filed on Nov. 18, 2009, which claims the priority date of Korean Application 10-2008-0120589, filed on Dec. 1, 2008, and Korean Application 10-2009-0029521, filed on Apr. 6, 2009, the contents of which is being hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a canopy tent, and more particularly, to a canopy tent, which is easy to be installed and dismantled by an elastic force of a compression spring arranged in a connection device mounted on the top of the tent and by an elastic force of tent poles connected to support poles.
2. Background Art
In general, canopy tents are called “collapsible tents” or “folding tents”, and means tents, which can be installed and dismantled while support poles and tent poles constituting a tent frame are expanded or collapsed.
Recently, automatic umbrella style canopy tents configured to be rapidly and easily pitched or closed in a manner similar to the motion of a conventional automatic umbrella have been developed.
As shown in FIG. 1 , one of the conventional automatic umbrella style canopy tents includes: a connection member 1 mounted on the top of the tent; a plurality of support poles 2 radially hinge-coupled to the connection member 1 to form the outward appearance of the tent; and a guide shaft 3 vertically connected to a lower portion of the connection member 1 .
A compression spring 4 and a cylindrical elevation guide 5 are fit onto the outer face of the guide shaft 3 in order. The elevation guide 5 receives a downward-direction movement force by the compression spring 4 , and a stopper 6 is screw-fastened to a lower end of the guide shaft 3 in order to prevent a separation of the elevation guide 5 from the guide shaft 3 . Here, a plurality of auxiliary support poles are radially hinge-coupled to the elevation guide 5 , and then, are hinge-coupled to the support poles 5 one-to-one.
As described above, in the case that the elevation guide 5 is pulled downwardly or the support poles 2 are expanded outwardly, the conventional automatic umbrella style canopy tent is installed when the support poles 2 are expanded and the expanded support poles 2 are supported by the auxiliary poles 7 while the elevation guide 5 automatically moves downwardly along the guide shaft 3 by a restoring force of the compression spring 4 .
In this instance, because a strong descending force is applied to the elevation guide 5 by the restoring force of the compression spring 4 and a connection end portion of the auxiliary support pole 7 connected with the elevation guide 5 is located lower than a connection end portion connected with the support pole 2 , the expanded support poles 2 are not folded again and can keep the expanded state in a lock condition.
In the above state, when the compression spring 4 folds the support poles 2 with a power greater than the restoring force, the auxiliary support pole 7 applies an ascending force to the support poles 2 , and hence, the elevation guide 5 moves upwardly along the guide shaft 3 while contracting the compression spring 4 , so that the tent can be dismantled.
However, the conventional automatic umbrella style canopy tent is configured in such a way as to be installed while the auxiliary support pole 7 is expanded horizontally and to be dismantled while the auxiliary support pole 7 is folded vertically, and hence, an elevation height (h) of the elevation guide 5 becomes longer because a rotational angle of the auxiliary support pole 7 is increased.
Therefore, as the elevation height of the elevation guide 5 becomes longer, a height of the tent is reduced and the interior space of the tent becomes narrower, and hence, it requires a user's excessive operation force when the tent is installed or dismantled.
Moreover, because the compression spring 4 is exposed to the outside, the user may be injured while installing or dismantling the tent, and the tent may not be installed or dismantled smoothly when the compression spring 4 is corroded.
SUMMARY OF THE INVENTION
Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior arts, and it is an object of the present invention to provide a canopy tent, which can be rapidly and easily installed and dismantled by an elastic force of a compression spring disposed in a connection device mounted on the top of the tent and by an elastic force of tent poles connected to support poles.
It is another object of the present invention to provide a canopy tent, which includes a plurality of poles constituting a frame of the tent, first and second joint members for connecting the poles with each other, and a flexure preventing pipe mounted between the first joint member and the second joint member to prevent the installed tent from being collapsed by the external force or stumbled by a draft of air.
To accomplish the above object, according to the present invention, there is provided a canopy tent including: a main body having a plurality of joint rings formed on the outer surface thereof and a hollow interior; a sliding member having a plurality of joint rings formed on the outer surface thereof and a downwardly protruding cylinder formed therein; support poles, each having one end, which is hinge-coupled to the joint ring of the main body, and the other end, which is connected to a tent pole for standing the tent fabric upright, and which has a joint ring formed on the outer face of a pole connection portion; and a joint bar having one end, which is hinge-coupled to the joint ring of the sliding member, and the other end, which has one side hinge-coupled to a first connection bar hinge-coupled to the joint ring of the support pole and the other side hinge-coupled to a second connection bar hinge-coupled to the joint ring of the main body, wherein the hollow interior of the main body is equipped with a compression spring and a spring holder, the spring holder is coupled to the lower portion of the cylinder, and the cylinder of the sliding member is fitted into the hollow interior of the main body from the top of the hollow interior such that the cylinder is movable in the upward and downward directions.
Moreover, the sliding member further includes a retaining portion, which is formed on a side of the lower end portion thereof in such a way that a stopper is caught thereto, and a fastening ring, which is formed on the outer surface of the main body for fixing the stopper thereto.
Furthermore, a cover is connected to the top of the sliding member, and the cover has a through hole formed on the upper face thereof to allow a user to connect a cord to the retaining ring formed on one side of the stopper caught to the retaining portion of the sliding member to thereby release the stopper.
Additionally, the spring holder includes a through hole to allow the user to insert a cord into the through hole to form a ring so that the user can install the tent by downwardly pulling the ring.
In addition, each of the poles includes: a first pole having one end hinge-coupled with the connection device located on the top of the tent and the other end joined to the first joint member; a plurality of second poles, each having one end joined to the first joint member and the other end fixed to the second joint member; a plurality of third poles, each having one end joined to the second joint member and the other end fixed to the fixing member; and a flexure preventing pipe mounted on the outer face of the second pole for preventing flexure of the second pole, wherein the fixing member is joined with the third pole and has a T-shaped through hole to which a fixing ring mounted at an edge of the lower end portion of the tent fabric is inserted and fixed thereinto.
As described above, the canopy tent according to the present invention can be rapidly and easily installed by the elastic force of the compression spring disposed in the connection device and by the elastic force of the poles connected to the support poles and can be rapidly dismantled by the poles, which are folded in a direction of the central axis of the connection device mounted at the top of the tent.
Furthermore, the canopy tent according to the present invention is prevented from being collapsed by the external force or stumbled by a draft of air because it includes the flexure preventing pipe mounted on the outer face of each pole.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which:
FIG. 1 is a view showing an example of the use of a conventional canopy tent;
FIG. 2 is a view showing an example of the use of a canopy tent according to a first preferred embodiment of the present invention;
FIG. 3 is a partially exploded view of a connection device according to the first preferred embodiment of the present invention;
FIG. 4 is a view showing a folded state of the connection device;
FIG. 5 is a view showing an operation process of a stopper according to the first preferred embodiment of the present invention;
FIGS. 6 and 7 are views showing an operational state of the connection device;
FIG. 8 is a view showing a connected state of poles of the canopy tent according to a second preferred embodiment of the present invention;
FIG. 9 is a view showing a connected state of poles of the canopy tent according to the second preferred embodiment of the present invention;
FIG. 10 is an exploded view of a second joint member according to the second preferred embodiment of the present invention; and
FIG. 11 is view showing a used process of a fixing member according to the second preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will be now made in detail to the preferred embodiments of the present invention, which can be easily embodied by those skilled in the art, with reference to the attached drawings.
FIG. 2 is a view showing an example of the use of a canopy tent according to a first preferred embodiment of the present invention, FIG. 3 is a partially exploded view of a connection device according to the first preferred embodiment of the present invention, FIG. 4 is a view showing a folded state of the connection device; and FIG. 5 is a view showing an operation process of a stopper according to the first preferred embodiment of the present invention.
First, as shown in FIGS. 2 to 5 , the canopy tent according to the present invention includes a tent fabric 11 , poles 12 , sag preventing members 14 , connection members 16 and 17 , fixing members 18 , and a connection device 100 .
The poles 12 constitute a frame of the tent 10 and are mounted in various forms according to the structure and area of the tent fabric 11 produced in various shapes and colors.
At least one sag preventing member 14 is located on a part of the outer face of the tent fabric 11 , and the poles 12 are respectively inserted into the sag preventing member 14 to keep the form of the tent fabric 11 as it is when the poles 12 are expanded or folded, so that the tent 10 can be more easily installed or dismantled.
The connection device 100 is mounted on the top of the tent 10 for allowing the poles 12 , which are radially expanded, to be expanded or folded in one direction. The connection device 100 includes a cover 110 , a sliding member 120 , a main body 130 , support poles 140 , a joint bar 150 , a first connection bar 152 , a second connection bar 154 , and a stopper 160 .
The main body 130 of the connection device 100 includes: a hollow interior 132 formed therein, for example, in a cylindrical shape; a plurality of fastening rings 136 and 138 protruding from the outer surface of the central portion and the lower end portion; and a through hole 134 formed on the top thereof for inserting and moving the sliding member 120 therein.
The sliding member 120 includes: a cylinder 121 downwardly protruding from the inner surface thereof for allowing a upward insertion and movement of the main body 130 ; a joining portion 122 protruding from the outer surface of the central portion thereof for screw-coupling with the cover 110 ; a plurality of joint rings 124 protruding from the lower end portion thereof and hinge-coupled with the joint bar 150 ; and a retaining jaw 126 , to which the stopper 160 is retained between the joint rings 124 , which are formed at the lower end portion thereof, in one direction.
Each of the support poles 140 includes: a pair of hinge portions 142 formed on one side thereof and hinge-coupled to the joint rings 136 and 138 of the main body 130 ; a pole connection portion 144 for connecting the poles 12 to stand the tent fabric 11 upright; and a joint ring 146 protrudingly formed on the outer face of the pole connection portion 144 and hinge-coupled with the first connection bar 152 .
The joint bar 150 has one end hinge-coupled with the joint ring 146 of the sliding member 120 and the other end which has one side hinge-coupled to the first connection bar 152 hinge-coupled to the joint ring 146 of the support pole and the other side hinge-coupled with the second connection bar 154 hinge-coupled to the joint ring 138 of the main body 130 .
The cover 110 is screw-coupled to the top of the sliding member 120 , and includes a plurality of screw holes 112 formed on the upper portion thereof and a through hole 114 formed on a side of the lower end portion thereof.
The stopper 160 includes: a hinge coupling portion 162 hinge-coupled to a fastening ring 139 formed on the outer surface of the main body 130 ; an elastic spring 163 mounted at the lower portion of the hinge coupling portion 162 ; a retaining portion 164 caught to the retaining jaw 126 formed on a side of the lower end portion of the sliding member 120 ; and a retaining ring 165 , which is formed in the opposite direction of the retaining portion 164 , and, for instance, to which a cord is connected.
Here, in a state where the retaining portion 164 of the stopper 160 is caught to the retaining jaw 126 of the sliding member 120 , when the cord connected to the retaining ring 165 is exposed to the outside through the through hole 114 of the cover 110 , the user can release the retained state of the stopper 160 by pulling the exposed cord.
A compression spring 170 and a spring holder 172 are arranged on the hollow interior 132 of the main body 130 , the spring holder 172 and the lower portion of the cylinder 121 are screw-coupled with each other, and the cylinder 121 of the sliding member 120 is inserted into the hollow interior 132 from the top of the main body 130 , and then, moves vertically therein.
The spring holder 172 has a through hole 174 formed downwardly from the upper portion thereof. When the cord is inserted into the through hole 174 to form a ring and the tent 10 is spread out to be installed, the through hole 174 can help the user to finally install the tent 10 by downwardly pulling the ring.
FIGS. 6 and 7 are views showing an operational state of the connection device. In order to install the canopy tent according to the present invention, as shown in FIGS. 6 and 7 , when the user grasps the connection device 100 , which is located at the top of the folded tent 10 , with the hand, and upwardly rotates the support poles 140 , which are folded relative to the connection device 100 , with the hand, the tent poles 12 connected to the support poles 140 are upwardly expanded.
In this instance, while the compression spring 170 compressed inside the hollow interior 132 of the main body 130 is expanded, the tent poles 12 connected to the support poles 140 can be easily expanded in the upward direction even by a small external force transferred from the user's hand.
Here, when the tent poles 12 connected to the support poles 140 are expanded upwardly, the sliding member 120 slides down, and the joint bar 150 hinge-coupled to the sliding member 120 evenly at regular intervals in a radial direction moves downwardly.
Moreover, while the first and second connection bars 152 and 154 that respectively have one end of which is hinge-coupled with the joint bar 150 and the other end of which is connected to the support poles 140 and the main body 130 are expanded in the upward direction that the support poles 140 are expanded, the support poles 140 , the joint bar 150 , the first and second connection bar 152 and 154 , which are in a folded state, are rotated and expanded upwardly.
After that, in the state that the support poles 140 are expanded at a predetermined angle (for instance, within a range of 70 degrees to 80 degrees) relative to the main body 130 , when the user continuously pulls the cord, which is drawn out in the downward direction of the main body 130 and connected to the spring holder 172 , in the downward direction, the sliding member 120 lowers to the maximum, and the retaining portion 164 of the stopper 160 mounted on the side of the main body 130 is caught and fixed to the retaining jaw 126 of the sliding member 120 .
In the meantime, in order to dismantle the canopy tent, when the user pulls the cord, which is illustrated in FIG. 5 and connected to the retaining ring 165 of the stopper 160 mounted on the side of the main body 130 , with the hand, the retaining portion 164 caught and fixed to the retaining jaw 126 of the sliding member 120 is separated from the retaining jaw 126 , and hence, the retained condition is removed.
In this instance, while the compression spring 170 , which is in an expanded state inside the hollow interior 132 of the main body 130 , is compressed, the poles 12 , which are connected to the support poles 140 and radially expanded, are folded at a regular angle by their own elastic force.
Here, when the poles 12 connected to the support poles 140 are folded downwardly, the sliding member 120 slidably moves in the upward direction, and the joint bar 150 hinge-coupled to the sliding member evenly at regular intervals in the radial direction are moved in the upward direction.
Furthermore, while the first and second connection bars 152 and 154 , each of which has one end hinge-coupled with the joint bar 150 and the other end connected to the support poles 140 and the main body 130 , are folded in the downward direction that the support poles 140 are folded, the support poles 140 , the joint bar 150 , the first and second connection bar 152 and 154 , which are arranged around the main body 130 , are rotated and folded downwardly.
In the state where the poles 12 connected to the support poles 140 are folded at a predetermined angle (for instance, in the range of 60 degrees to 70 degrees) relative to the main body 130 , when the user collects and folds the support poles 140 more relative to the main body 130 , the sliding member 120 ascends to the maximum and the support poles 140 are completely folded relative to the main body 130 .
After that, the user can connect connection members 16 and 17 between the poles 12 inserted into the sag preventing members 14 of the tent fabric 11 in such a way as to make two-stage or three-stage foldable poles 12 . After that, the user folds the poles 12 inwardly or outwardly in one direction, and then, puts and keeps the canopy tent in a case (not shown) after rolling the tent fabric 11 in one direction.
Meanwhile, FIG. 8 is a view showing a connected state of poles of the canopy tent according to a second preferred embodiment of the present invention, FIG. 9 is a view showing a connected state of poles of the canopy tent according to the second preferred embodiment, FIG. 10 is an exploded view of a second joint member according to the second preferred embodiment, and FIG. 11 is view showing a used process of a fixing member according to the second preferred embodiment.
As shown in FIGS. 8 to 11 , the canopy tent according to the second preferred embodiment of the present invention includes first poles 210 , first joint members 220 , second poles 230 , second joint members 240 , third poles 250 , fixing members 260 , and flexure preventing pipes 270 .
The connection device is mounted on the top of the tent 10 for allowing the first poles 210 expanded radially to be expanded or folded in one direction, and each of the first poles 210 has one end hinge-coupled through the support poles 140 connected with the connection device 100 located at the top of the tent 10 and the other end hinge-coupled to each of the first joint members 220 .
Each of the first joint members 220 includes: hinge coupling portions 221 formed at both sides thereof and joined to the first pole 210 and the second pole 230 ; and a pole supporting portion 222 for supporting and preventing the first pole 210 and the second pole 230 joined to the hinge coupling portion 221 from being rotated at a predetermined angle, for instance, within the limit of 200 degrees to 220 degrees.
Each of the second poles 230 has one end hinge-coupled to the first joint member 220 and the other end fixed to the second joint member 240 .
Each of the second joint member 240 includes a coupling member 241 coupled with the second pole 230 and a rotation member 245 coupled with the third pole 250 .
The coupling member 241 has guide projections 242 formed at both sides thereof, an elongated hole 243 to which the rotation member 245 is hinge-coupled, and a fixing projection 244 formed on the lower end portion of the front face meeting the rotation member 245 .
The rotation member 245 has an open upper portion, guide grooves 246 , which are formed on the inner surface of both sides of the rotation member 245 and correspond to the guide projections, and a fixing hole 247 corresponding to the fixing projection 244 .
Each of the third poles 250 has one end joined to the second joint member 240 and the other end fixed to the fixing member 260 .
Each of the fixing members 260 has, for instance, a T-shaped through hole 262 , and a fixing ring 19 mounted at an edge portion of the lower end portion of the tent 10 is, as shown in FIGS. 11( a ) and ( b ), inserted and fit in a longitudinal direction of the T-shaped through hole 262 , and as shown in FIG. 11( c ), rotated at an angle of 90 degrees toward a head portion of the T-shaped through hole 262 , and then, is fixed.
The flexure preventing pipe 270 is mounted on the outer face of the second pole 230 mounted between the first joint member 220 and the second joint member 240 to prevent the outward flexure of the second pole 230 , so that the side of the canopy tent can keep a straight form as shown in FIG. 8 .
As described above, the canopy tent according to the present invention is configured in such a way that the tent poles can be easily folded or expanded relative to the central axis of the tent in a state where the poles are connected with one another, and hence, can be rapidly installed and dismantled.
Additionally, the canopy tent according to the present invention can be conveniently installed and dismantled with a small power and can prevent that the installed tent is collapsed by the external force or stumbled by a draft of air.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
|
The present invention relates to a connection device installed on a top of a canopy tent, comprising: a main body having a hollow interior, a sliding member having an interior with a downwardly protruding cylinder, support poles each having one end hinged to the main body, and the other end connected to a tent pole for standing the tent fabric upright, a joint bar having one end hinged to the sliding member, and the other end having one side hinged to a first connection bar hinged to the support pole and the other side hinged to a second connection bar hinged to the main body; The hollow interior of the main body is equipped with a compression spring and a spring holder. The cylinder of the sliding member is fitted into the hollow interior of the main body from the top of the hollow interior to be movable in the upward and downward directions to set up or taken of the tent canopy.
| 8
|
BACKGROUND
[0001] This invention relates to a process and a device for adding a controlled dose of fluid to the eye. Conventional eye drops are difficult to use even for experienced patients. They are more problematic for children, the elderly, patients with impaired motor skills, and caregivers. Patients risk improper dosing, contamination of the eye dropper container, expensive waste due to spillage, and injury to the eyes from contact with the dropper bottle. These factors contribute to poor compliance. In addition, preservatives are added to the drops to provide medicine stability and reduce microbial contamination. These preservatives are known to cause morphological changes to the cornea, conjunctiva, and surrounding areas, which lead to irritation, stinging, burning, epiphora, hyperemia, keratitis, allergic and immune response, and scarring (1).
[0002] Subsequent reflex tearing leads to dilution of the medication, which can further alter pharmacodynamics. The quantity and concentration of the drug from conventional eye drops must be increased in order to account for the decreased bioavailability due to reflex tearing and the biophysiologic dynamics of the eye's structure. At least 80% of the drop is lost from excess tearing, spillage due to overflow from the eye's cul de sac, and rapid drainage through the nasolacrimal duct which increases the risk of systemic side effects (2). The eye has a tear turnover rate of 16% per minute which doubles after using conventional eye drops (3). In order to reach the aqueous humor at measurable levels, high concentrations of a drug are needed for one drop to be effective since only 3% of conventional eye drops penetrate the cornea (4).
[0003] New delivery systems include solutions, suspensions, sprays, gels, inserts, emulsions, mucoadhesives, collagen shields, and contact lenses. These are in addition to devices designed to facilitate the instillation of a drop to the eye. Although these methods are relatively safe, they have not fully addressed the main problems associated with drop delivery. In addition, they have not been implemented on a large scale (5).
[0004] What is needed is a new method and device that overcomes the basic challenges of the current eye dropper system which are:
[0005] 1. Gravity.
[0006] 2. Reduced bioavailability due to reflex tearing, eye drop spillover, and eye drop splash-back.
[0007] 3. Difficult physical manipulation of the eye dropper bottle system by patients and caregivers.
[0008] 4. Psychological apprehension of the eye drop instillation process.
[0009] 5. Eye drop preservation process.
SUMMARY OF THE INVENTION
[0010] The subject invention provides a new method for applying a controlled dose of most any ophthalmic agent to the eye without an eyedropper. The device of the present invention comprises a filter matrix attached to an elongated flexible handle separated by a barrier membrane. With the present invention, the medication is impregnated within the filter matrix of the filter matrix applicator (FMA) through various methods and ready for activation at a later desired date.
[0011] The applicator facilitates the easy instillation of a fully medicated dose of controlled, precise concentration to provide an expected pharmaceutical effect.
[0012] Each medicated applicator can contain a single dose of medication within the filter matrix as intended for its own pharmaceutical intent. The medication would be impregnated into the sterile filter matrix, which can be designed with modifiable levels of absorption and saturation according to the pharmacodynamics or chemical properties of the drug being delivered. The length, width, and depth of the filter matrix along with the type of interwoven material determine the absorption and saturation level of the filter matrix.
[0013] The device and method of the present system is designed to provide an optimal ocular drug delivery, which increases compliance by patients and effectiveness of delivery of the pharmaceutical agent. The present invention further achieves the following objectives:
Objective 1: Making instillation easy, fast, and comfortable for the patient, clinician, or caregiver. Objective 2: Increasing bioavailability and optimizing contact time while maintaining or improving effective dosing. Objective 3: Decreasing or eliminating the use of preservatives while maintaining pH balance; thereby reducing side effects. Objective 4: Decreasing the dilution and drainage caused by excess tearing, spillage, and splash-back. Objective 5: Decreasing the risk of contamination and injury to the eye by eliminating the dropper bottle modality. Objective 6: Improving handling and transport (6).
BRIEF DESCRIPTION OF DRAWINGS
[0020] FIG. 1 illustrates a top perspective view of an embodiment of the filter matrix applicator (FMA).
[0021] FIG. 1A illustrates a cut away view of an embodiment of the filter matrix.
[0022] FIG. 2 illustrates the front perspective view of an embodiment of the FMA.
[0023] FIG. 3 illustrates an alternative disc form embodiment of the FMA before the treated disk is installed.
[0024] FIG. 3A illustrates a cutaway view of the treated disk of the alternative embodiment of the FMA.
[0025] FIG. 4 illustrates the bonded disk in the alternative disc form embodiment of the FMA.
[0026] FIG. 5 illustrates an alternative embodiment of the FMA with an un-bonded solid-state carrier.
[0027] FIG. 5A illustrates a view of the solid-state carrier for the FMA.
[0028] FIG. 6 illustrates the solid-state carrier bonded to form the FMA.
[0029] FIG. 7 illustrates the FMA inside a protective sleeve.
[0030] FIG. 7A illustrates an un-medicated FMA used as an applicator for ophthalmic agents from an eye dropper bottle
[0031] FIG. 8 illustrates the FMA with a handle which behaves as both the barrier membrane and the handle.
[0032] FIG. 9 illustrates the administration of an ophthalmic agent using the FMA by pulling down the lower lid and applying to the conjunctiva.
[0033] FIG. 10 illustrates the experiment using a mydriatic treated FMA to demonstrate dilation.
[0034] FIG. 11 illustrates the experiment using an antimuscurinic treated FMA to demonstrate the effect upon accommodation.
[0035] FIG. 12 illustrates the experiment using an ocular hypotensive treated FMA to demonstrate the efficacy in lowering intraocular pressure as compared to a standard ocular hypotensive eye drop.
[0036] FIG. 13 illustrates the experiment using an olopatadine treated FMA to treat ocular allergy.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Referring to FIGS. 1, 1A, and 2 , the present invention comprises a device, a filter matrix applicator (FMA) ( 10 ) comprising a flexible elongated handle ( 15 ) bonded to a sterile filter matrix ( 20 ), which can be medicated or un-medicated, separated by a barrier membrane ( 30 ). Flexible elongated handle ( 15 ) of a length of approximately but not limited to 2 inches, with a thickness of at least 0.004 inches. It can be made of paper, plastic or another suitable flexible material. The width of the handle can be 0.25 of an inch.
[0038] The barrier membrane ( 30 , 90 ) can be made of a semi-permeable or impermeable material such as rubber, plastic, waxes, petroleum base product, or another material that is waterproof. As shown in FIG. 7A , once the medicated fluid is placed upon the filter matrix ( 80 ), the barrier membrane ( 90 ) traps the fluid within the structure of the filter matrix ( 80 ) thereby providing a more exact dose of ophthalmic agent to be instilled to the eye. If a pre-medicated FMA ( 10 , 32 ) is used, as shown in FIGS. 1,2,3, and 4 , saline which is a non-irritant solution instead of a medicated fluid ( 95 ) is applied to the FMA prior to instillation to the eye as shown in FIG. 9 . With the present invention any non-irritant eye solution can be use.
[0039] In one embodiment, as shown in FIGS. 1 and 1A , the barrier membrane ( 30 ) extends the width of the top end of elongated handle ( 15 ) and forms a barrier thereto. In an alternative embodiment in FIG. 3 , the filter matrix ( 40 ) is in the form of a disc and the barrier membrane ( 52 ) forms the base at one end of handle ( 35 ). As depicted in FIGS. 3 and 3A , filter matrix ( 40 ) is bonded to base ( 52 ) of handle ( 35 ) to form FMA ( 32 ).
[0040] Referring to FIG. 8 , there is shown an alternative embodiment of FMA ( 100 ) wherein the handle ( 105 ) forms the barrier membrane. In alternative embodiment illustrated in FIG. 8 , the barrier membrane serves as both the handle ( 105 ) and the waterproof impermeable or semi-permeable membrane. In this embodiment barrier membrane extends the full length and width of the handle ( 105 ) and bonds to the filter matrix ( 110 ).
[0041] As shown in FIGS. 1, 2, and 3 , the filter matrix ( 20 , 40 ) is separated from the handle by a semi-impermeable or impermeable waterproof barrier-membrane ( 30 , 52 ) provides the mechanism wherein the FMA ( 10 ) facilitates the efficient and effective entrapment and release of medication into solution for the end-user. In use, the barrier membrane ( 30 , 52 ) optimizes the amount of medication captured within the FMA ( 10 , 32 ) and precipitated into the resultant drop that is instilled to the eye. The system and device ( 10 ) of the present invention reduces the amount of medication that is absorbed or lost in the elongated handle in the prior art without a barrier membrane.
[0042] In the present invention, as depicted in FIGS. 1, 2, 3 and 3A , the filter matrix ( 20 , 40 ) can comprise a plurality of strands or fibers interwoven to create a size that can vary to optimize the capture and release of the ocular agent being used. Interwoven fibers ( 20 , 40 ) form the matrix to capture the granules of the medicated ocular agent therein. The size of the filter matrix ( 20 ) can be ⅜ inches in depth to facilitate a surface area for saturation of the ocular agent within the matrix. The perimeter of the filter matrix ( 20 ) in FIG. 1 can be a total of 1 inch. Alternatively the diameter of the filter matrix ( 40 ) in FIG. 3 can be 0.25 of an inch in diameter.
[0043] However, the shape of the filter matrix ( 20 , 40 ) can vary in size and shape to aid in efficient instillation of the ocular agent to the eye. In the illustrated embodiment in FIG. 1 , the filter matrix ( 20 ) depicts a polygonal shape and in FIG. 3 , the filter matrix ( 40 ) is depicted having a circular shape. However, the shape of the filter matrix ( 20 , 40 ) is not limited to either shape; instead the shape can vary to optimize the capture and release of the ocular agent. The filter matrix ( 40 ) depicted in FIGS. 3 and 1 can be circular, oval, elliptical, or polygonal.
[0044] In the present invention, each medicated FMA ( 10 ) depicted in FIG. 1 can contain one prescribed medicated dose for a patient. The medication would be impregnated within the FMA ( 10 ) in a sterile environment. The fiber can be of various materials with variable levels of absorption and saturation. In use, the more water repellant the strands the lower the saturation level of the filter matrix and the more water absorbent the strands the higher the saturation level of the filter matrix. The strands of the filter matrix can be absorbent such as cotton or less absorbent such as plastic. In the present invention, the strands of the FMA can be made of cotton, rayon, silk, nylon, various plastic fibers, synthetic fibers and/or any other suitable material. The filter matrix can be made of a blend of fibers to adjust the capture and release properties of the FMA ( 10 ).
[0045] In FIGS. 1 and 3 , the semi-flexible handle ( 15 , 35 ), which is separated from the filter matrix ( 20 , 40 ) by the impermeable membrane ( 30 , 50 ) allows for easy placement of the fluid to the eye. The handle can be constructed in various shapes and sizes and of various materials to aid in easy instillation of an ophthalmic agent and to further facilitate proper drop formation to be applied to the matrix.
[0046] In an alternative embodiment illustrated in FIGS. 5 and 5A , the volume of the medication is stabilized within an inert semi-permeable carrier ( 55 ) made of materials similar to, but not limited to polyvinyl methylcellulose, loosely bound in place to the elongated handle ( 60 ) by an inert viscous carrier such as mineral oil or petrolatum or similar compounds ( 55 ). The solid-state filter matrix ( 65 ) shape can be flat or columnar. The filter matrix ( 65 ) size is based on the nature and quantity of active ingredient of the medication. This embodiment reduces the need for a drop to be stabilized on the FMA ( 62 ) and also allows for time—release of an ophthalmic compound.
[0047] An additional embodiment of the FMA is un-medicated ( 70 ), as shown in FIG. 7 . In this embodiment, the FMA can be used by placing one drop of ocular medication from an eye dropper bottle onto the FMA and applying directly to the eye in the fashion described in FIG. 9 . Therefore, medications not available in a prepackaged FMA form can be administered with the advantages of this new technology.
Creation of the FMA
[0048] Once the FMA ( 10 , 32 ) is manufactured as shown in FIGS. 1, 2, and 3 , the filter matrix ( 20 , 40 ) can be either non-medicated or pharmaceutically impregnated under aseptic conditions. The process of impregnation of filter matrix ( 20 , 40 ) can occur under aseptic conditions in one of a variety of ways enumerated below:
1) absorbing the medication into the filter matrix in liquid form followed by the removal of the liquid by evaporation within 72 hours; 2) pulverizing the powdered or crystallized form of the medication into the filter matrix; 3) freeze drying the medication into the filter matrix; or 4) stabilizing the volume of medication within an inert viscous carrier/semi-permeable barrier as depicted in the filter matrix in FIG. 7 .
[0053] As depicted in 1 , 2 , 3 , 3 A, 4 , and 5 , once the medicated FMA ( 10 , 32 , 62 ) is prepared under sterile conditions, it can be then individually aseptically packaged and sealed in a sterilized sleeve as depicted in FIG. 7 which can be made of paper, plastic or another suitable material. This medicated filter matrix applicator system of the present invention in FIGS. 1, 3, and 5 facilitates instilling ophthalmic agents in various head positions and body posture, virtually independent of gravity. FIG. 9 illustrates the administration of an ocular compound to the eye using the present invention FMA ( 10 ) depicted in FIG. 1 .
Operational Method
[0054] In use, the medicated filter matrix applicator is removed from the sterilized sleeve ( FIG. 7 ) and a drop of sterile saline is placed upon the filter matrix. In the case of FIG. 5 , the medicated FMA is simply removed from the protective sleeve and is ready for application without activation from sterile saline. The lower lid of the eye is then pulled down to expose the conjunctiva of the eye and the FMA is directly applied thereto ( FIG. 9 ). The pharmaceutically active solution then is released from the FMA to the eye via capillary action (which describes how a liquid can move against the forces of gravity), the forces of covalent bonding, and Van der Waal forces which determine the attraction of particles in a solution at different temperatures). This method of drug delivery would allow for the entrapment and effective release of medication for easy instillation of a dose of medicine to an eye nearly independent of gravity, less dependent on dexterity, with reduced spillage and overflow, and the possibility of fewer or no preservatives.
[0055] In the case of FIG. 5 , the semi-permeable component of the FMA ( 65 ) is slowly dissolved after being released from the inert viscous carrier. Furthermore, direct corneal and conjunctival absorption is able to be optimized because of reduced reflex tearing, drop spillage, and drop splash back, as is the case in all FMA embodiments ( 10 , 32 , 62 , 70 , 100 ). Alternatively, a dry medicated FMA ( 10 , 32 , 62 ) can be held in the lower fornix to enable the natural and reflex tears to extract the medication from the filter matrix.
[0056] This method of ophthalmic agent delivery is easy to use, safe, sanitary, comfortable, and effective. It greatly reduces the physical and psychological difficulties associated with eye drop instillation via standard eye dropper bottles and tubes. The medicated FMA has a vast range of applications ranging from personal use for eye medicine instillation for patients, to instillation of ocular agents by caregivers in a private or institutional setting, to the application of diagnostic ocular agents for practitioners, even to the instillation of ocular agents and pharmaceuticals in a veterinary setting. Patient, caregiver, and health care practitioner preference will result in significantly improved compliance and reduced side effects.
Experiments
[0057] Referring to FIG. 10-13 , there are shown several experiments conducted by the applicant to show the ease of use and efficacy of the device. Referring to FIG. 10 , there is shown an experiment measuring the level of dilation using hydroxyamphetamine/tropicamide. In this experiment, the filter matrix applicator (FMA) was impregnated with approximately ⅓ of a drop of hydroxyamphetamine/tropicamide. Then the FMA was air-dried at room temperature over a 72 hour period. To activate the FMA, a drop of saline solution was applied to the FMA and the FMA was subsequently applied to the left eye. Measurements were observed under normal room lighting. As depicted, it was noted that upon application of the hydroxyamphetamine/tropicamide—FMA (hFMA) to the left eye while leaving the right eye as an untreated control, the subject experienced a substantial and effectively sustained dilation in the left eye. The hFMA was easily self-applied in less than 2 seconds using a mirror. There was no report of burning upon instillation (as is usually noted with standard hydroxyamphetamine/tropicamide eye dropper bottle instillation). However, gradual onset of low grade burning was noted within 1 minute of application (although significantly less and of shorter duration than with hydroxyamphetamine/tropicamide in eye drop form from an eye dropper bottle). The subject was a 35 year old male.
[0058] Referring to FIG. 11 , there is shown the results of the experiment measuring the amplitude of accommodation using hydroxyamphetamine/tropicamide. The method of impregnation of the filter matrix applicator (FMA) was via solution absorption followed by air-drying at room temperature over a 3 day period. The FMA was then activated with the application of a drop of saline solution and then the FMA was subsequently applied to the left eye. The subject was a 35 year old male. It was noted that upon application of the hydroxyamphetamine/tropicamide—FMA (hFMA) to the left eye while leaving the right eye as an untreated control, that the subject experienced a 35% reduction in accommodative ability. Again, the subject reported no burning upon installation, which is usually noted with standard hydroxyamphetamine/tropicamide eye dropper bottle installation. However, gradual onset of low grade burning was noted within 1 minute of application using the FMA, but the burning was significantly less and of shorter duration than with hydroxyamphetamine/tropicamide using a conventional eye dropper bottle.
[0059] Referring to FIG. 12 , there is shown the results of the experiment using timolol. The method of impregnation of the filter matrix applicator (tFMA) was via solution absorption followed by air-drying at room temperature for a 24 hour period. The timolol—FMA (tFMA) was then activated with the application of saline solution and subsequently applied to the right eye. One eye drop of timolol from an eye dropper bottle was instilled in the left eye. The results were subsequently monitored and compared.
[0060] The FMA was easily self-applied by the patient in less than 2 seconds using a mirror. The subject reported no burning upon installation nor was there ocular irritation. In addition, no conjuctival or corneal staining was noted in the right eye. However, the subject reported significant and sustained irritation (grade 5 out of 10) of the left eye. In addition, there was mild corneal staining noted along with subsequent nasal conjunctival staining with grade 1 hyperemia upon eye drop instillation from the eye dropper bottle. The corneal staining and hyperemia persisted over a 24 hour period (in the left eye), while there continued to be no complaint about the right eye. Subject refused further testing from the eye dropper bottle of timolol due to the discomfort. A sizable reduction in intraocular pressure (IOP) was noted using both methods (nearly 30% reduction in the right eye and 35% reduction in the left eye). It should be noted that due to the impregnation technique, the tFMA contained approximately ⅓ of the volume of 1 standard eye drop (therefore it is assumed that the tFMA contained only ⅓ of the active ingredient of timolol, yet still attained a robust IOP reduction). This demonstrates similar efficacy at a significantly lower dose—which is closer to the minimum effective dose (MED) required to achieve the targeted IOP reduction (lowering the amount of active and inactive ingredients and preservatives to achieve the desired effect). The subject was a 65 year old male.
[0061] Referring FIG. 13 , there is shown the results of the experiment using olopatadine. The method of impregnation of the filter matrix applicator (FMA) was via solution absorption followed by air-drying at room temperature for a 24 hour period. The olopatadine—FMA (oFMA) was then activated with the application of saline solution and subsequently applied to the left eye. It was noted that upon application of oFMA to the left eye while leaving the right eye as an untreated control, that the subject experienced a substantial and sustained comfort over a 24 hour period in the left eye. The FMA was applied easily in less than 2 seconds using a mirror (as the oFMA was self-applied). There was no report of burning upon instillation nor was ocular irritation noted. In addition, no conjunctival or corneal staining was noted in the left eye. The right eye remained untreated for the duration of day 1. On day 2, one olopatadine eye drop from a bottle was instilled in the right eye due to the subject's request to relieve allergic conjunctivitis symptoms—after which, relief was quickly achieved at a rate similar to that of oFMA. Although no subsequent conjunctival redness, staining, nor corneal staining was noted for the right eye, significant difficulty with instillation was observed. It took the subject several attempts before 1 drop was successful instilled into the subject's right eye.
[0062] In conclusion, the foregoing experiments show that the method of the present invention provides an easy, safe, sanitary, comfortable, and effective delivery of ocular pharmaceuticals to the eye. It greatly reduces the physical and psychological difficulties associated with eye drop instillation via standard eye drop bottles and tubes. As stated before, the medicated FMA and un-medicated FMA have a vast range of applications ranging from primary uses for eye medicine instillation for the individual patient, to installation of eye medication by a caregiver in a private or institutional setting, to the application and instillation of diagnostic eye pharmaceuticals and agents by healthcare practitioners, even to the instillation of ophthalmic mediations to veterinary patients. Patient, caregiver, and healthcare practioner preference will result in improved compliance and reduced side effects. Previous systems have been mainly paper fiber based. In addition, they were mainly used for the delivery of dyes into the eye for diagnostic purposes. If they were impregnated with medication, the amount of medication precipitated out into a drop was variable due to loss through the fibered strip over a period of time of saturation. The medicated FMA addresses this issue with the addition of a variable/adjustable absorptive filter matrix and a semi-permeable to impermeable waterproof membrane. This allows the filter matrix to hold the medication in a given area until it is precipitated out to the eye by applying a water-based solution (saline) over that same given area. Thus the FMA would then deliver a consistent and precise dose to the eye. The ability to have increased accuracy of dose and drug concentration decreases wasteful drop application and increases drug efficacy. This method can be easily adapted to replace most eye dropper bottle systems.
REFERENCES
[0000]
(1) S Dinslage, M Diestellhorst, A Weichselbaum, R Swerkrup. British Journal of Ophthalmology 2002; 86 1114-1117 doi 10.11362 BJ0.86.10.114
(2) Abdul-Fattah A M, Bhargawa H N, Korb D R, Glonek T, Finnemore V M, Greiner J V, Optom Vis Sci 2002 July; 79(7): 435-8
(3), (4), (7) A Lux, S Maier, S Dinslage, R Suverkrup, M Deistelhorst, British Journal of Ophthalmology 2003; 87 436-440 doi 10.11436/bjo.87.4.436
(5), (6) Basics of Ocular Drug Delivery Systems. International Journal of Research in Pharmaceutical and Biomedical Sciences. ISSN: 2229-3701
|
The invention is a device and a method for delivering a dose of a pharmaceutical agent to the eye. The device and method provide a safe and effective way to instill a specified dose of the agent to the eye virtually independent of gravity and posture. The device includes a filter matrix in which the fluid capture and release properties can be modified. The filter matrix is attached to a flexible handle with an impermeable or semipermeable membrane there between.
| 0
|
BACKGROUND OF THE INVENTION
The present invention relates to a joint member and a method of forming a joint between two stepped cementitious surfaces. It is of particular relevance to the joints in concrete floors.
Conventional concrete floors may require a joint system to allow for movement. There are a variety of known method of forming such joints: sealing joints with an elastomer to allow for movement; using an epoxy sealant; using a combination of the two types of fillers; or any of the above methods with a saw cut through the jointing material to allow for movement. These styles of filling provide support for the cementitious faces of the joint, but do not perform well or are expensive to construct.
An improvement in the method of forming a joint and the joint member to fit in a joint are disclosed in New Zealand Patent Nos 229154 and 247968. The method disclosed incorporates the insertion of an elongate divider plate means between two faces in a groove, channel or slot, the plate means having projections which bear against but not into the cementitious faces in order to provide two regions filled with a settable material. The joint member of New Zealand Patent No 247968 discloses such a divider plate means, with projections sloping upwardly and outwardly from a base to hold the joint member in place.
However both the method and the joint member described above cannot be used where the cementitious faces are necked, stepped or shouldered so that the joint, in cross-section, has two different widths. The use of, or creation of, such a cross-section and a joint member for use therein can be used to reduce the amount of setting material required, permit an increase in the width of a joint that can be repaired/made; and increase the range of joints which can be filled and thus protected from wear and tear of the edges of the blocks in a floor.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is the provision of a method of forming a joint between two cementitious, stepped surfaces which overcomes the disadvantages of the known methods described above. A further object of the present invention is the provision of an improved joint member.
The present invention provides a method of forming a joint between two cementitious faces along the length of the faces in which the space between said faces is not of a uniform cross-section but has at least two different widths and is stepped; said method comprising:
positioning a joint member between said faces, said joint member incorporating: a central upright portion; a lower portion attached to the lower end of the central portion for positioning the joint member relative to the lower walls of the faces; at least two flanges, one on each side of the central portion and secured thereto, said member being positioned such that a part or all of each flange rests on a shoulder or at the transition point between two differing widths of said faces, but do not touch the cementitious faces;
inserting a filling material between said joint member and each cementitious face such that the volume in the region of greatest width of the space between the faces is filled by said material, said flanges preventing any material falling below them; and
allowing said filling material to mature or set to form a joint.
Said method can further comprise the step of forming the joint to the desired shape with one, two or three saw cuts, depending on the cross-sectional shape of the joint prior to the use of the method.
Preferably said filling material is one that is rigid yet retains a degree of compressibility, for example an epoxy resin or an elastomeric product.
The present invention further provides a joint member for positioning between cementitious faces in which the space between said faces is not of a uniform cross-section but has at least two different widths and is stepped; said joint comprising: a central upright portion; a lower portion attached to the lower end of the central portion for positioning the joint member relative to the lower walls of the faces; at least two flanges, one on each side of the central portion and secured thereto, said member being positioned such that a part or all of each flange rests on a shoulder or at the transition point between two differing widths of said faces, but do not touch the cementitious faces.
Preferably said joint member is formed integrally of one material which is flexible but reasonably self supporting, for example polyvinyl chloride. Preferably said flanges are hingedly secured to the central portion of the joint member and are capable of a limited amount of rotation about the joint.
BRIEF DESCRIPTION OF THE DRAWINGS
By way of example only, a preferred embodiments of the present invention are described in detail with reference to the accompanying drawings, in which:
FIG. 1 is a cross-section through a stepped joint with a first preferred embodiment of the joint member of the present invention in position and the joint completed; and
FIG. 2 is a cross-section through a second preferred embodiment of the joint member of the present invention in position and the joint complete.
DETAILED DESCRIPTION
Referring to FIG. 1, a space 2 between two cementitious faces 3, 4 is thereshown. The space 2 incorporates two regions (a lower region 5 and an upper region 6) of differing widths. A shoulder 7 which is approximately horizontal, links the faces 3, 4 between the two regions 5, 6. The faces 3, 4 are approximately parallel in each region 5, 6.
A first embodiment of a joint member 8 is shown in position in the space 2. The member 8 includes a central upright portion 9, a locating head 10 and two side flanges 11. The central portion 9 is shown as including a top portion 12 with a handle 13. A part of the top portion 12 and handle 13 is shown as protruding above the level of the faces 3, 4. If so desired, the protruding part can be broken off once the joint is formed. Alternatively, if so desired, the top portion 12 can be omitted from the member 8 so that the central portion 9 extends to the surface, level with the top of the faces 3, 4 or slightly below (when the joint member 8 is in position in the space 2).
The locating head 10 is positioned at the bottom of the member 8. Said head 10 includes two side projections 14, with one projection 14 on opposing sides of the member 8, about a longitudinal axis (not shown) of the joint member 8. The projections 14 are resilient and capable of upward movement in the direction shown by arrow A (relative to the central portion 9) when the member 8 is inserted into the space 2. The open or non-use position of the projections 14 is shown in dotted outline on the drawing. The width across from one end of one projection 14 to the opposite end of the opposed projection 14 is slightly greater than the width of the lower region 5 but less than the width of the upper region 6.
The side flanges 11 are positioned at least one or more on opposing sides of the central portion 9 about the longitudinal axis of the member 8 between the head 10 and top portion 12. In FIG. 1 two alternative embodiments of the shape of each said flange 11 are thereshown. In the first embodiment (on the left of FIG. 1) the shape of the flange 11 in cross-section is substantially rectangular. The flange 11 includes a necked area 15 which permits this area 15 to act as a hinge, allowing limited rotational movement of the flange 11 relative to the central portion 9. The width of each flange 11 is less than the distance from the longitudinal axis of the member 8 to a face (3 or 4) of the upper region 6. Thus the flanges 11 do not touch or bear against the faces 3 or 4 of the upper region 6, but touch or rest on the respective shoulder 7 between the two regions 5, 6.
The right hand flange 11 shows an alternative shape of the flange 11. The cross sectional shape of the flange 11 is rectangular with a semi-circular node 16 positioned on the underside of the flange 11 at the end remote from the central portion 9. The non-use or at rest position of the flange 11 relative to the central portion 9 is shown in dotted outline on the right hand flange 11.
Referring to FIG. 2, a second embodiment of the joint member 28 is thereshown. Parts with like numbers to the embodiment shown in FIG. 1 are like numbered. The member 28 includes a central upright portion 29, a locating head 30 and two side flanges 31. The central portion 29 includes a top portion 32. A part of this top portion 32 may protrude above the level of the faces 3, 4.
The locating head 30 includes two sets of side projections 14, one above the other on the head 30. Each set of projections 14 includes one projection 14 on opposing sides of the member 28, about a longitudinal axis (not shown) of the joint member 28.
The side flanges 31 are positioned at least one on opposing sides of the central portion 29 about the longitudinal axis of the member 28, and between the head portion 30 and top portion 32. The shape of each flange, in cross-section is arcuate and downwardly curved, so that when the member 28 is not in use the distance between the two outer ends of the flanges 31 is just great enough to rest on the shoulder 7. The end of the flanges 31 adjacent the central portion 29 of the member 28 are connected to a collar 29a, a thickened portion of the central portion 29. The flanges are of constant thickness along their length. The length of each flange 31 is such that the flange 31 does not touch the side walls 3, 4.
The joint member 8, 28 is made integrally, preferably of one material. However, the flanges 11, 31 may be of an alternative grade plastics material, if so desired, to provide the flanges 11, 31 with a greater degree of flexibility. The member 8, 28 can be made by injection or extrusion moulding, as is desired, or any other appropriate method. The member 8, 28 may be made of any appropriate long lasting resilient plastics material(s). An example of such material is polyvinyl chloride.
The joint member 8, 28 may be formed in pre-determined lengths of the described cross-sectional shape. Alternatively, if so desired, the member 8, 28 may be formed in indeterminate lengths and cut to suit the length of each space 2.
The above described joint member 8, 28 and method of forming a joint is as follows: the appropriately dimensioned space 2 is prepared. If the space 2 is to be formed along an expansion crack 18 in a concrete block or between two blocks of concrete, a saw or saws of appropriate radius and thickness can be used in known manner to cut and prepare the space 2. In practice it has been found that a space 2 with the following dimensions works well: an upper region 6 with a width 9 millimeters and depth between 10 to 15 millimeters; and a lower region with a width of 3 millimeters and a depth of 20 to 40 millimeters.
The joint member 8, 28 is inserted along the length of the space 2. The member 8, 28 is inserted to a depth sufficient for the projections 14 of the head 10 to engage with the surfaces of the lower region 5 of the space 2 and such that the flanges 11, 31 rest on the shoulder 7 of the space 2 along some or all of the underside of the flanges 11, 31. The filling material 17 is inserted into the spaces between the member 8, 28 and the faces 3, 4 of the upper region 6 of the space 2. The weight of the material 17 will tend to flatten the flanges 11, 31 slightly against the respective shoulder 7. The resilience of the projections 14 of the head 10, 30 and the shape of the flanges 11, 31 prevent the weight on the joint member 8, 28 from pushing the member 8, 28 further into the space 2.
In the embodiment shown in FIG. 1 the part of the top portion 12, 32 and handle 13 projecting above the top of the joint and top surface of the material 17 can be broken off or removed when the material 17 has set. If the joint member 8, 28 is dimensioned such that the top of the central portion 9 is level with the top of faces 3, 4, or slightly below this level, then a top portion 12, 32 will not be needed.
If so desired, the filling material 17 may actually be two separate materials--the space 2 being part filled with one material (which is allowed to set or mature) and then fully filled with a second material. As the joint member 8, 28 is of a material that can remain upright without further support the member 8, 28 will remain in the correct, upright position for such a process.
The filling material 17 may be any appropriate material suitable for use with concrete or cement products, and which is resilient and allows for some amount of movement, for example an epoxy resin or an elastomer.
|
A method of forming a joint (2) and the member (8, 28) used therein between two cementitious faces (3, 4) in which the space between the faces is not of uniform cross-section, but has at least two different widths (5, 6) and is stepped with a shoulder (7). The joint member has a central upright portion (9), a lower portion or head (10) for positioning the member relative to the lower faces (5). The lower portion includes one or more sets of projections (14) which are resiliently deformable. Flanges 11 on either side of the central portion have limited movement relative to the central portion rest on the shoulder (7) of the faces when the space between the member and the faces 3, 4 is filled with a resilient but compressible product.
| 4
|
This application is a continuation of application Ser. No. 07/526,842 filed May 22, 1990, now abandoned.
The invention relates to thermoplastically processable elastomeric block copolyetheresteretheramides, a process for producing them and their use for the production of shaped articles. Production takes place, in particular, by extrusion, injection molding, coinjection molding, injection welding, or blow molding.
BACKGROUND OF THE INVENTION
The block etheramides of the invention, such as the polyetherpolyamides described in DE-PS 30 06 961 or the polyetheresteramide block copolymers (polyetheresteramides) described in DE-PS 25 23 991, belong to the category of polyamide elastomers (PA-elastomers). The term "block copolyetheresteretheramide" emphasizes that the polyether contents of the products according to the invention are linked to the polyamide segments by ester or amide bonds. For the sake of simplicity, the term "PA-elastomers" will be used herein.
The most important PA-elastomers found in the market nowadays undoubtedly include those whose polyamide segments --CO--D--CO-- had resulted from the polymerization or the polycondensation of caprolactam, laurolactam, or the corresponding ω-amino-α-carboxylic acids in the presence of a dicarboxylic acid.
According to DE-PS 25 23 991, PA-segments having terminal carboxyl groups are esterified with α,ω-dihydroxypolyethers and the polyetheresteramides are thus obtained. According to DE-PS 30 06 961, PA-segments are reacted with α,ω-diamino polyethers to form polyetheramides. Both methods of synthesis of PA-elastomers are subject to a number of restrictions; hence, a highly flexible PA-6-elastomer having a flexural modolus of elasticity of less than about 200 N/mm 2 (measured in the dry state) and acceptable properties for processing and use cannot be produced by the batch processes according to the teachings of either of these references.
DE-PS 25 23 991 describes various linear or branched aliphatic polyoxyalkylene glycols as components which have a flexibilizing effect, in particular the following:
______________________________________I: Polyoxyethylene glycol = α, ω-dihydroxypoly-(oxy- ethylene).II: Polyoxypropylene glycol = α, ω-dihydroxypoly-(oxy- 1,2-propylene),III: Polyoxytetramethylene = α, ω-dihydroxypoly-glycol (oxytetramethylene),IV: Copolyethylene glycol-propylene glycol______________________________________
Although highly flexible products can be produced with component I, they have the distinct disadvantage that they absorb considerable quantities of water when in contact with moisture. Thus, with 50% by weight of segments of I, the water absorption corresponds approximately to the weight of the respective block polymer.
Polyoxypropylene glycol (II) can, if its average molar mass exceeds the value of 1000 required for highly flexible, readily processable PA-6-elastomers, be mixed only to a limited extent with the respective short-chain, carboxyl-terminated PA-6-segments (Mn≧1300), so a high molecular weight polymer cannot be built up. A further distinct disadvantage, at least for batchwise production processes, is that polyoxypropylene glycol is very sensitive to elevated temperatures and tends to discolor and decompose under the normal polycondensation conditions. In addition, it can only be esterified with difficulty due to its individual secondary alcohol function.
Polyoxytetramethylene glycol (III) is poorly miscible with PA-6-segments, which limits the potential polymers to less flexible products. The drawbacks mentioned with regard to I and II also apply to IV.
According to the teaching of DE-OS 30 06 961, PA-6-elastomers can be produced by condensation of PA-6 containing terminal carboxyl groups with
V: α,ω-diamino-poly-(oxy-1,2-propylene) or
VI: α,ω-bis-3-aminopropyl-poly-(oxytetramethylene),
wherein an industrial, hydrogenated or non-hydrogenated, dimerized fatty acid or "dimeric acid" containing 36 carbon atoms (which can contain a small quantity of trimerised fatty acid containing 54 carbon atoms) is preferably used as a chain length regulator.
It is just as impossible to produce a highly flexible PA-6-elastomer using the flexibilizing component V as with component II which is comparable therewith. This is due to the limited miscibility of PA-6-segments (Mn ≧1300) with the respective poly-(oxy-1,2-propylene)-segments. However, the thermal stability of diamine V is significantly higher than that of diol II. Its reactivity toward carboxyl groups is greater than that of diol II.
The use of component VI for producing a highly flexible PA-6-elastomer is hindered by its poor miscibility with the PA-segments. In addition, the diaminopolyether VI is so expensive (due to its complicated synthesis) that it cannot be considered for the commercial production of a highly flexible PA-6- or PA-12-elastomer.
According to the teaching of DE-PS 30 06 961, a satisfactory result cannot be achieved either with the polyether component V containing terminal amino groups or with VI for the synthesis of a highly flexible PA-12-elastomer. Polyetherdiamine VI fails for the above-mentioned reason and with diamine V, having contents of more than about 30% by weight in the PA-12-elastomer, only products which have yellow to brown discoloration and are sometimes markedly decomposed can be produced.
If a PA-12 containing terminal carboxyl groups is polycondensed with the above-mentioned components I to IV according to DE-PS 25 23 991, then the disadvantages already mentioned with regard to I, II or IV also apply. With III as flexibilizing component, PA-12-elastomers of almost any flexibility having very good properties for processing and use can generally be produced. However, these PA-12-elastomers still have the following distinct disadvantages.
The first disadvantage resides in the inadequate compatibility of PA-12-segments having an average molar mass higher than about 1000 and segments of the flexibilizing component III having an average molar mass higher than about 1100 in highly flexible elastomers having a content of III amounting to more than about 45% by weight. The lack of compatibility is revealed by the cloudy milky appearance of the PA-12-elastomers in the solidified (crystallized out) state; the strength of parts produced therefrom is diminished transversely to the processing direction owing to the delaminability of the layered structures. The increased susceptibility to mechanical wear, for example, the abrasion of such PA-12-elastomer products, is closely related. The above-mentioned disadvantages cannot be eliminated by modifying the production process.
The second disadvantage of these PA-12-elastomers is that they are not unreservedly suitable for coinjection molding or injection welding. The latter process is a special injection molding process in which polymer A is injected in a conventional injection mold onto a solidified part of the same-or usually a different-polymer inserted therein. Finished articles of which the functions can be optimally adapted to the specific requirements by suitable polymer combinations are obtained in this way. For example, it is possible by this process to restrict the elasticity in a given finished article to the regions where it is actually advantageous and to keep the remainder of the article rigid. The process also affords considerable advantages in the coloring of injection moldings.
The fundamental condition for the application of injection welding to a specific pair of polymers is good adhesive strength at the contact faces between the polymers. High strength interlayer adhesion is achieved because the injection molded polymer melts a thin layer of the inserted plastic part and the melts of the two materials are mixed together. The miscibility of the polymers must be ensured; obviously, the process fails if the polymers are incompatible.
With regard to PA-12-elastomers with co-component III according to DE-PS-25 23 991, they are preferably combined with other elastomers of this type or with unmodified PA-12. The adhesive strength achieved in these cases is generally good, but it does not meet all requirements, particularly if the molecular weight of the PA-12-elastomer is comparatively low.
The production of good adhesive strength is difficult at relative viscosities (as a measure of the molecular weight of the PA-12-elastomers) of less than 2.1 (measured as 0.5% solution in m-cresol at 25° C. according to DIN 53727).
DESCRIPTION OF THE INVENTION
The object of the present invention is to provide new polyamide elastomers without the above-mentioned numerous disadvantages in preparation and use.
The block copolyetheresteretheramides according to the invention cover a very wide flexibility range. Expressed in terms of the flexural modulus of elasticity--measured according to DIN 53452 on dry test pieces--this range lies between about 40 and 700 N/mm 2 . The products according to the invention are suitable for the production of injection molded, extruded, blow molded, coinjection or injection welded parts. Other processing methods can equally well be adopted for these products.
The invention also relates to a process for producing the block copolyetheresteretheramides according to the invention which resides in the fact that carboxyl-terminated polyamides (component --CO--D--CO--) are polycondensed with equimolar quantities of α,ω-dihydroxypolyoxytetramethylene (component --O--E--O--) or α,ω-diaminopolyoxy-1,2-propylene (component --NH--F--NH--). In other words, the CO--D--CO group is reacted with either the O--E--O group or the NH--F--NH group. The two resulting materials are then copolymerized to form the final product.
The carboxyl-terminated polyamides are preferably obtained from lactams containing 6 to 12 carbon atoms, or from linear ω-amino-α-carboxylic acids containing 6 to 12--especially 11 and 12--carbon atoms and dicarboxylic acids containing 6 to 36 carbon atoms for forming terminal carboxyl groups. It is preferably to use caprolactam and laurolactam and, as the ω-aminocarboxylic acid, ω-aminoundecanoic acid, ω-aminolauric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, and dimerized fatty acid.
Processes for producing carboxyl-terminated polyamides are known. Various processes for linking these polyamides to α,ω-dihydroxypoly-(oxytetramethylene) to the corresponding etheresteramide partial structure are also known. The process is usually carried out under reduced pressure at temperatures of between 200° and 280° C. in the presence of effective esterification/-transesterification catalysts. Tin(II)-compounds, for example Tin(II)-oxide, Tin(II)-salts of mono- or dicarboxylic acids, as well as zirconium compounds, for example Zr-tetraisopropylate are suitable, among others, as catalysts.
The etheramide partial structure is also formed in the above-mentioned temperature range. The partial structures can be built up in succession or simulataneously. The synthesis of one of the two or both partial structures can also take place simultaneously with the build-up of the polyamide segments --CO--D--CO. This shows that numerous variations of the process are possible. The examples demonstrate this more fully.
As already mentioned, the block copolyetheresteretheramides according to the invention can be modified with other polymers and can exist as a mixture with copolyolefins bearing one or more carboxyl, carboxylate, and carboxylic acid anhydride groups and other polar molecular radicals. They can very easily be mixed, for example, with grafting products of ethylene/propylene or ethylene/propylene/diene copolymers and maleic acid anhydride. In this, they are comparable to the PA-elastomers of the prior art, as described in CH-PS 655 941. The melt index, flexibility, notched impact strength, and processibility of PA-elastomers, among other things, can be positively influenced by the addition of, for example, polar copolyolefins.
The addition of reinforcing agents or fillers, such as glass fibers or minerals, is also possible. The PA-elastomers according to the invention can obviously contain the usual additives such as anti-oxidants, UV-stabilizers, antistatic agents, conductive carbon black, flame-retardant additives, etc.
The following examples illustrate but do not limit the invention.
The relative viscosities of the products have been measured in accordance with DIN 53727 using 0.5% solutions in m-cresol at 25° C. Mechanical properties were measured on dry test bars; the flexural modulusof elasticity according to DIN 53452, the notched impact strength accordingto DIN 53453, and the tensile strength and elongation at break according toDIN 53455. The melting temperatures (maxima) were measured using a DSC device, model 990 produced by DuPont. All other tests are described in theindividual examples.
COMPARATIVE EXAMPLE 1
according to DE-OS 30 06 961
Various block copolyetheramides with polyamide-6-segments are produced. Thechain length regulator of the PA-6-segments is non-hydrogenated dimeric acid having a molar mass of 570 g/mole (Pripol 1013 produced by Unichem), the flexibilizing component is an α,ω-diaminopoly(oxy-1,2-propylene) having an average molar mass of 1980 g/mole (Jeffamin D 2000 produced by Texaco). 0.3% (24 g) of antioxidant (Irganox 1330 produced by Ciba-Geigy) is added to the individual reaction mixtures in each case.
The block copolyetheramides are produced by pouring all components, together with 0.5 liter of water, into a steel autoclave with stirrer, temperature indicator, and the other necessary devices. The autoclave is thoroughly purged with pure nitrogen and then sealed. The reactants are heated to 260° C. with stirring, and the internal pressure is adjusted to about 18 bar. This pressure is maintained for two hours and isthen reduced to atmospheric pressure in the course of one hour by slowly opening the autoclave. Polycondensation is subsequently carried out for eight hours with passage of dry nitrogen. At the end, the polymer is extruded through a die and the strand of melt is granulated after cooling in a water bath.
Only batch 1.1, a milky cloudy product having a relative viscosity of 1.61,could be granulated. The other batches could not be granulated owing to their low viscosities (molar masses) and were brittle in the solidified state. Further details are given in Table I.
Test bars were injection molded from batch 1.1 and their flexural modulus of elasticity was determined to be 410N/mm 2 . Batches 2 to 5 could notbe injection molded. These products demonstrate that highly flexible PA-6-elastomers cannot be obtained by this method.
TABLE I__________________________________________________________________________ Characterisation of the block copolyetheramides Rel. PA-Segment PolyetherTest Cl a) DS b) P c) visc. Mn d) % by wt. e) Strength Appearance__________________________________________________________________________1.1 5.6 0.535 1.865 1.61 5910 23.4 delami- cloudy, like nated f) mother-of- pearl1.2 4.8 0.714 2.486 1.39 4040 31.3 brittle yellowish, opaque1.3 4.4 0.803 2.797 1.36 3395 35.2 brittle yellowish, opaque1.4 3.6 0.98 3.42 1.31 2315 43.2 brittle yellowish, opaque__________________________________________________________________________a) Caprolactam,b) dimeric acid,c) Jeffamin D 2000d) Calculated from the quantity of dimeric acid and the reacted caprolactam. Unreacted caprolactam was separated by 12hour extraction of the products with water at 95° C. The conversion of the caprolactawas uniformly about 90%.e) Calculated from the formulations.f) Delamination in processing direction on test pieces and extruded strands.
COMPARISON EXAMPLE 2
The general formula of these products corresponds to that given in DE-PS 2523 991. In particular, however, DE-PS 25 23 991 does not claim dimerized fatty acid, of the type used here, as co-component. Instead of a titanium compound as esterification catalyst according to DE-PS 25 23 991, a substantially more effective tin-(II)-compound according to DE-OS 34 28 404 is used in this case.
Test 2.1
28 kg of caprolactam, 8.28 kg of dimerized fatty acid and 150 g of Irganox 1330 (antioxidant) are poured into a 100 liter steel autoclave equipped with a stirrer, temperature indicator, and vacuum pump, are heated to 225° C. under nitrogen with continuous stirring; and are kept at this temperature for two hours. 9.04 kg of α,ω-dihydroxypoly(oxytetramethylene) having an molar mass of 1000 g/mole (Terathane 1000 produced by DuPont) and 10.25 kg of an equivalent dihydroxypolyether having an molar mass of 2000 g/mole (Terathane 2000 produced by DuPont) are then introduced together with 100 g of the tin-(II)-salt of 2-ethylhexanoic acid produced by Acima/Buchs, Switzerland.
The autoclave is closed immediately afterwards and nitrogen is introduced to a gauge pressure of about 1 bar. In the closed autoclave, the components are stirred for one hour at 250° to 255° C. The pressure is then released and a vacuum is applied immediately after normalpressure has been achieved. An internal pressure of 1/mbar is reached within about one hour. Polycondensation is carried out for 6 hours at thispressure and at a product temperature of 250° C.
The block copolyetheresteramide obtained is then quenched and granulated. The melt of the product is milky/cloudy, and opaque and yellowish in the solidified state. The relative viscosity is 1.54, the maximum melting point is 212° C., and 3.95 kg (14.1% based on caprolactam used) of the caprolactam is distilled off during polycondensation.
Despite its very high flexibility (flexural modulus of elasticity: 145 N/mm 2 ), this product was completely useless; injection molded test bars had a pronounced layered structure, the layers of which could easily be separated from one another mechanically. Extruded strands of the product cut longitudinally at one end could easily tear in the processing direction. The fibrillar structure of the polymers could be detected at the dull crack faces. The polymer consequently had very poor strength transverse to the processing direction. The other characteristic values ofthe polymers are as follows:
Molar mass of the PA-segments: 2132 g/mole (allowing for the caprolactam distilled off during production thereof as well as 1.1% by weight of caprolactam which had been extracted from the polymer with water at 85° C. within 8 hours):
Molar mass of the two polyethers (Terathane): 1365 g/mole
Melting point (maximum): 212° C.
Test 2.2
In the same way as described in Test 2.1, a block copolyetheresteramide is produced from 28 kg of caprolactam, 8.28 kg of Pripol 1013, and 14.53 kg of Terathane 1000. The relative viscosity of the product thus obtained is 1.65, the molar mass of its PA-segments is 2160 g/mole (corresponding to aloss of 3.9 kg of caprolactam during polycondensation and 0.9% by weight ofcaprolactam in the polymer; see Test 2.1).
Melting point (maximum): 213° C.
The measurement of the flexural modulus of elasticity on injection molded test bars yielded a value of 255 N/mm 2 . The test bars exhibited layers which could easily be removed mechanically but not in such a pronounced fashion as in product 2.1.
Comparison Example 2 shows that useful, highly flexible PA-6-elastomers cannot be obtained by this method.
EXAMPLE 3
Test 3.1: (to be compared with Comparison Example 1 and Test 2.1)
A block copolyetheresteretheramide is produced from 28 kg of caprolactam, 8.28 kg of Pripol 1013, 6.25 kg of Jeffamin D 2000, 9.04 kg of Terathane 1000, and 4 kg of Terathane 2000 using 100 g of Tin(II)-dioctoate (catalyst) and 150 g of Irganox 1330 (antioxidant). As in Comparison Example 2, caprolactam, Pripol 1013, Jeffamin D 2000, and Irganox 1330 arepoured into steel autoclaves and heated to 255° C. with stirring andthe passage of nitrogen. The reactants are kept at this temperature for 2 hours. The partial structure in which the PA-6-segment is linked to the α,ω-diamino-poly(oxy-1,2-propylene) is formed in the course ofthe reaction. The two types of Terathane are subsequently added along with the catalyst. After addition thereof, the procedure adopted in Test 2.1 ofComparison Example 2 is followed. The product is of the formula ##STR3##in which ##STR4##represents a polyamide segment
The product had the following characteristic values:
______________________________________Relative viscosity: 1.77Melting point (maximum): 211.5° C.Molar mass of the PA-segments: 2150 g/moleRatio x:y = 3.53:1______________________________________
The product was substantially transparent as a granulate. It did not exhibit layered structures or delamination/fibrillation either in the formof extruded strands or injection molded test bars. Its flexural modulus of elasticity was 140 N/mm 2 ; a value of 560 N/mm 2 was measured at -40° C. The elastomer did not exhibit a breakage to -40° C. in the test to measure the notched impact strength.
Test 3.2: (to be compared with Comparison Example 1 and Test 2.2)
A block copolyetheresteretheramide is produced from 28 kg of caprolactam, 8.28 kg of Pripol 1013, 6.25 kg of Jeffamin D 2000, and 11.04 kg of Terathane 1000 under the conditions given for Test 3.1; the catalyst and antioxidant are also the same as in Test 3.1.
The product had the following characteristic values:
______________________________________Relative viscosity: 1.699Melting point (maximum): 211.5° C.Molar mass of the PA-segments: 2160 g/moleRatio x:y = 3.53:1______________________________________
With the exception of its flexural modulus of elasticity, for which a valueof 165 N/mm 2 was measured, this elastomer corresponded to the product of Test 3.1.
The viscosity or the molar mass of such PA-6-elastomers can be readily increased by subsequent condensation in the solid phase which is normal for conventional polyamides. For this purpose, each product is treated in finely divided form - for example as a granulate - at a temperature slightly below its melting point under vacuum or under dry nitrogen.
The subsequent condensation conditions for this PA-6-elastomer were as follows:
______________________________________Temperature (heating medium): 180°Pressure: 0.1 to 0.2 mbarDuration: 7 hoursQuantity of granulate used: 250 g______________________________________
The subsequent condensation tests were carried out with four further batches. The results obtained can be inferred from the following Table.
______________________________________Relative viscosity Before AfterBatch Subsequent condensation Subsequent condensation______________________________________3.2/2 1.696 1.9563.2/3 1.693 1.9773.2/4 1.7 1.9393.2/5 1.696 1.914______________________________________
COMPARATIVE EXAMPLE 4
Product: according to DE-PS 25 23 991; production process: according to DE-OS 34 28 404 with a highly effective Tin(II-compound as the esterification catalyst.
88.5 g of ω-aminolauric acid, 16.92 g 1,12-dodecanedioic acid, 159.1 g of Terathane 2000, 0.5 g of Tin(II)-dibenzoate, and 0.75 g of Irganox 1330 are melted in a 1 liter multi-necked flask with metal stirrer, distillation receiver, temperature probe, nitrogen supply pipe, and vacuumconnection, with passage of nitrogen, and are mixed with stirring. The contents of the flask are further heated; polycondensation commences at about 175° C. with the formation of water (predominantly from ω-aminolauric acid). After about 2 hours and after the product temperature has reached 260° C., the evolution of water comes to a virtual standstill. At this moment, the melt is milky/cloudy and virtuallyopaque. The water of reaction (about 7 ml) is removed from the distillate receiver. Vacuum is then applied and polycondensation is carried out for 75 minutes with stirring at 255° to 260° C. and pressure of 0.4 to 0.6 mbar.
During polycondensation, the viscosity of the melt increases considerably, but its milky/cloudy appearance does not change. On completion of the reaction, a portion of the melt is pressed in a suitable mold to a 3 mm thick slab and is caused to solidify by slow cooling. The slab is white and opaque. The remainder of the melt is poured onto a metal plate as a strand having a cross section of 10 to 40 mm 2 and is cooled. The strand obtained in this way does not differ in appearance from the pressedslab. Some test bars, 1 cm wide and about 8 cm long, are cut from the slab.The flexural modulus of elasticity of the elastomer is determined as about 55N/mm 2 .
Despite its high flexibility, this PA-12 elastomer is useless for the production of extruded or injection molded parts owing to the defective transverse strength of the strands which, after applying a cut longitudinally to the direction of flow, could easily be torn over an average length of more than 5 cm (similarly to the products of Comparison Example 2). A pronounced fibrillar structure could be detected at the dullcrack faces. The shearing force acting upon the melt during the pouring of the strands was sufficient to expose the melt to such pronounced extensional deformation that a fibrillar structure was produced.
With normal processing methods, such as injection molding or extrusion, very much higher forces of extension and shearing occur, with the result that the fibrillation of such a PA-12-elastomer appears to a much more undesirable extent therein.
The other characteristic values of the elastomer were as follows:
______________________________________Relative viscosity: 1.836Melting point (maximum): 165.5° C.Average molar mass of the PA-segments: 1317 g/mole______________________________________
EXAMPLE 4
to be compared with Comparison Example 4
A block copolyetheresteretheramide is produced under the same reaction conditions as in Comparison Example 4 from 88.5 g of α-aminolauric acid, 16.92 g of 1,12-dodecanedioic acid, 103.67 g of Terathane 2000, and 55.32 g of Jeffamin D 2000. 0.5 g of Tin(II)-dibenzoate is used as the catalyst and 0.75 g of Irganox 1330 as the antioxidant.
On completion of polycondensation, which takes 60 minutes and is therefore shorter than in Comparison Example 4, the clear, firmly transparent melt of the elastomer is processed in the manner described hereinbefore into a 3 mm thick slab and into strands.
The flexural modulus of elasticity of the product was 53N/mm 2 . However, the strands had a much higher transverse strength than the elastomers from Comparison Example 4. They did not exhibit a fibrillar structure which would have enabled a crack longer than about 1 cm parallelto the direction of flow to be formed. Instead, the cracks swerved to the side. In contrast to Comparison Example 4, the crack faces were not dull but glossy.
Other characteristic values of the elastomer:
______________________________________Relative viscosity: 1.726Melting point (maximum): 165.5° C.Molar mass of the PA-segments: 1317 g/moleRatio x:y = 1.87:1______________________________________
COMPARISON EXAMPLE 5
The interlayer adhesion during the injection welding of two block copolyetheresteretheramides according to DE-PS 25 23 991, both produced bythe process according to DE-OS 34 28 404, are tested.
The more rigid product (5-1) is obtained from 36.7 kg of laurolactam, 1.27 kg of 1,12-dodecanedioic acid, and 5.5 kg of Terathane 1000. The quantity of catalyst used Tin(II)-dioctoate) is 90 g, and 100 g of Irganox 1330 serves as the antioxidant. The lactam and the dicarboxylic acid are initially melted in a 100 liter autoclave under nitrogen and the mixture obtained is homogenized by stirring. The two components are then reacted within four hours at 285° C. to 290° C. to form the corresponding carboxyl-terminated polyamide.
After the melt cools to 260° C., the other above-mentioned components are added and mixed with the polyamide. Polycondensation takes place with stirring at a pressure of 0.5 to 1 mbar. Polycondensation is completed about 40 minutes after the beginning of the vacuum phase.
The relative viscosity of the elastomer was 1.93. At a rate of 200 mm/min, its tensile strength was 33N/mm 2 and its elongation at break was 255%.
The more flexible product (5-2) is obtained in a similar manner from 30 kg of laurolactam, 2.57 kg of 1,12-dodecanedioic acid, and 12 kg of Terathane.
______________________________________Catalyst: 90 g of Tin(II)-dioctoateAntioxidant: 135 g of Irganox 1330______________________________________
After 60 minutes of polycondensation, the product was formed with a relative viscosity of 1.963. Its tensile strength was 35N/mm 2 and itselongation at break was 285 to 290%.
Half tensile test specimens (10 mm wide and 4 mm thick) are initially produced from the material of Test 5-1 to measure the adhesion strength between the two elastomers. For this purpose, half of the injection mold is filled with a suitably adapted piece of metal.
The polymer 5-1 is injection molded under the following conditions:
______________________________________Mass Temperature: 237° C.Pressure: 733 barMetering time: 10.8 secInjection time: 0.9 secCycle time: 38 sec______________________________________
The tensile test specimens of 5-1 are then inserted into the mold instead of the piece of metal. The elastomer 5-2 is then injected onto them under the following conditions:
______________________________________Mass Temperature: 234° C.Pressure: 733 barMetering time: 10.4 secInjection time: 1.35 secCycle time: 43.6 sec______________________________________
A tensile test is carried out on the parts composed of Tests 5-1 and 5-2, under the same conditions. A tensile strength of 16.4 N/mm 2 is found with an elongation at break of 35%.
EXAMPLE 5
As described in Comparison Example 5, the interlayer adhesion between elastomer 5-1 and the following block copolyetheresteretheramide 5-3 is tested. The PA-12-elastomer 5-3 produced from 30 kg of laurolactam, 3.65 kg of dodecanedioic acid, 10.15 kg of Terathane 1000, and 2.25 kg of α, ω-diamino-poly(oxy-1,2-propylene) having an molar mass of 425 g/mole (Jeffamin D 400 produced by the company Texaco), by a process similar to that employed in Test 5-2.
______________________________________Catalyst: 90 g of Tin(II)-dioctoateAntioxidant: 135 g of Irganox 1330______________________________________
The elastomer was formed with a relative viscosity of 1.957.
Ratio x:y=1.93:1.
With a flexural modulus of elasticity of 280 N/mm 2 , its flexibility corresponded to that of the elastomer 5-1 (275 N/mm 2 ). The tensile strength of 5-3 was 37 N/mm 2 with an elongation at break of 258%.
To produce an adhesive assembly with 5-1, 5-3 is processed under the following conditions:
______________________________________Mass Temperature: 236° C.Pressure: 733 barMetering time: 8.7 secInjection time: 1.31 secCycle time: 38.4 sec______________________________________
Tensile testing of the elastomer assembly 5-1/5-3 yields a tensile strengthof 16.7 N/mm 2 and an elongation at break of 157%. Energy at break is between 300 and 400% above the values of the combination of materials 5-1/5-2 (Comparison Example 5) as is determined from the respective stress/strain graphs by integration.
EXAMPLE 6
80 parts by weight of the product of Test 3.2 and 20 parts by weight of a highly flexible ethylene/propylene copolymer (ethylene content=84 mol %, melting point: about 48° C.) grafted with 0.5 parts by weight of maleic acid anhydride are fed into a twin screw extruder (WPF ZSK-30 produced by Werner and Pfleiderer, Stuttgart), and subsequently compoundedat 150 RPM and a melt temperature of about 250° C. The polymer mixture thus obtained is processed into test bars and the following mechanical properties were determined.
______________________________________Flexural modulus of elasticity: 100 N/mm.sup.2Notched bar strength at -40° C.: no breakage______________________________________
This Example shows that the flexibility can be increased by adding polyolefin elastomers of the type used here to the polyamide elastomers according to the invention.
|
Thermoplastically processable elastomeric block copolyetheresteretheramides from recurring units of the formula ##STR1## in which ##STR2## represents a polyamide segment containing terminal carboxyl groups and having an average molar mass of 700 to 10 000, --O--E--O-- is a poly-(oxytetramethylene)-segment having an average molar mass of 600 to 3 500, --NH--F--NH-- represents a poly-(oxy-1,2-propylene)-segment containing terminal amino groups and having an average molar mass of 350 to 2 500, x and y are integers from 3 to 35 and indicate the number of the respective, randomly arranged, recurring units, the ratio x:y of components A and B varying between 5:1 and 1:5.
The ether amides of the present invention can optionally be mixed with additives, fillers, modifiers, or other compatible polymers normally used in the processing of polyamides and which are suitable for the production of molded articles, for example by injection molding, coinjection, extrusion, blow molding, etc.
| 2
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the priority benefit of U.S. Provisional Patent Application Ser. No. 61/744,432 titled “MAGNETIC-ENABLED CONNECTOR DEVICE,” filed on Sep. 26, 2012, the specification of which is incorporated in its entirety herein by reference.
BACKGROUND
1. Technical Field
The disclosure relates to connectors for electronic devices and data communication. More particularly, the disclosure relates to self-aligning, magnetically biased connectors, including multi-pin connectors.
2. Prior Art
It is generally known to provide magnetic coupling elements in electrical and non-electrical connectors. Examples of connectors that include magnetic coupling elements are disclosed in U.S. Pat. Nos. 4,484,761; 4,776,406; 7,277,013 and 7,334,433. Examples of magnetic breakaway connection devices for power lines or cables are disclosed in U.S. Pat. Nos. 5,315,064 and 5,623,122.
Examples of other types of electrical connectors that include magnetic elements are described in U.S. Pat. Nos. 2,170,287; 3,363,214; 3,431,428; 3,521,216; 3,808,577; 4,844,582; 4,874,316; 5,401,175; 5,812,356; 5,816,825; 5,941,729; 5,954,520; 6,183,264; 6,250,931; 6,267,602; 6,478,614; 6,527,570; 6,561,815; 6,607,391; 6,623,276; 6,727,477; 6,988,897; 7,066,739; 7,264,479; 7,311,526; 7,351,066; 7,517,222; and in U.S. Patent Application Publication Nos. 2004/0209489; 2005/0208783 and 2005/0255718.
U.S. Pat. No. 7,264,479 describes a connector for connecting two coaxial cables, wherein the holding forces between two connector or adapter portions are formed by means of magnetic forces. The mutually facing end faces of the two adapter portions are each provided with disks or plates for grounding. For this reason, connectors of this type require a user to orient and align the two adapter portions axially with respect to one another before the magnetic forces act and peg-shaped contact elements can latch into the corresponding annular mating contact elements.
Multi-pin connectors are useful for connecting signal carriers, such as computer cables, to peripheral devices, such as printers or displays, or for connecting signal carriers or other cables to electronic equipment, such as medical equipment. Multi-pin connectors may incorporate elements for connecting a plurality of conductive paths. Known multi-pin connectors may include connectors known as “D-sub connectors.” A D-sub connector contains two or more parallel rows of pins or sockets usually surrounded by a D-shaped metal shield that provides mechanical support, ensures correct orientation, and may screen against electromagnetic interference.
One problem with prior art connectors that utilize threaded fasteners, for example, or which are not readily connected or disconnected, is that in environments where many cables and connectors are utilized, cable management becomes challenging. The rigid coupling implements, i.e., threaded fasteners, of known connectors makes untangling and proper wire or cable routing time consuming. A related problem is that sudden forces on such prior art connectors may cause irreparable damage to the connector, cable or electronic device. For example, in a hospital environment where electronic devices providing vital patient support functions are connected with prior art “hardline” connectors, medical personnel or others tripping over a cable could result in medical equipment falling and being damaged from impact, or other consequences that could be catastrophic to equipment and patients.
Another problem in the prior art is that connectors that utilize multiple pins are prone to damage from misalignment or attempting connection with respective portions in an improper orientation. Typical prior art multi-pin connectors utilize somewhat lengthy pins on the male connector portion, which may extend to a point that is generally flush with the connector shield. Because of their length, the pins are more prone to bending and deformation caused by damage when they are exposed, or by misalignment during the connection process. If connection is attempted before the connector portions are properly aligned, bending, deformation or other damage may result to one or more pin conductors, rendering the connector permanently damaged and useless.
Yet another shortcoming in prior art connectors, such as those that are mechanically connected to a computer, peripheral or other device, for example, using threaded fasteners or other rigid connectors, is that they require dexterity and visibility for connection in hard to reach or confined places, such as in the case where a number of connectors are engaged in the back of a computer or server in a tightly confined space, such as a server rack.
There is thus a need in the art for connectors that address the aforementioned problems in the prior art. The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above, and others.
SUMMARY OF THE INVENTION
One aspect of the invention provides a multi-pin connector assembly that may be connected more quickly and precisely than prior art connectors and which avoids a “hardline” connection to an electrical or electronic source or target. This aspect is achieved through the use of magnetic elements on respective male and female connector portions, as well as alignment surfaces, which cooperate to allow the user to bring the connector portions only into “rough” alignment before the magnetic forces pull the respective connectors into precise alignment and a complete connection. According to a related aspect of the invention, a connector may be used in confined locations, which would not permit the use of conventional connectors that require tools or manual turning of mechanical screws to complete connections.
Another aspect of the invention ensures proper orientation of the male and female portions of multi-pin connectors. This may be achieved through the use of a pair of magnetic elements on each of the male and female connector portions. The magnetic elements are oriented with opposite polarities, one of each pair having a north pole facing in a forward direction, and the other of each pair having a south pole facing in a forward direction. When the male and female connector portions are brought into proximity in the wrong orientation, the user experiences a tactilely-sensed repulsive force, indicating that the orientation is improper. When the connector portions are brought into proximity with the proper orientation, the attractive magnetic forces complete the connection and, in conjunction with alignment surfaces, bring the connectors and respective multiple pins into perfect alignment. According to another aspect of the invention, an audible “click” may be generated by the impact of respective connector surfaces to indicate to the user that the connector is in a completely connected state.
According to another aspect of the invention, contact pins are provided in a unique configuration which reduces the risk of damage from misalignment or otherwise. Contact pins on the male and female connector elements extend only a small amount beyond respective protective surfaces, such that the pins cannot be damaged from bending or breaking due to lateral forces. A male connector portion includes contact pins that extend only slightly beyond a protective annular opening in the male connector. A female connector portion includes spring-biased connector pins that extend only slightly beyond a protective annular opening in an unconnected state. In a connected state, the male connector pins push spring-biased female connector pins back into the respective annular openings and extend therein, providing further alignment and complete conductive paths.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other attendant advantages and features of the invention will be apparent from the following detailed description together with the accompanying drawings, in which like reference numerals represent like elements throughout. It will be understood that the description and embodiments are intended as illustrative examples and are not intended to be limiting to the scope of invention, which is set forth in the claims appended hereto.
FIG. 1 is an exploded view of a male portion of a connector according to an aspect of the invention.
FIG. 2 is an oblique exploded view of a female portion of a connector according to an aspect of the invention.
FIG. 3 is an oblique view showing male and female connector portions in a disconnected position.
FIG. 4 is an oblique view showing male and female connector portions in a connected position.
FIG. 5 is an enlarged, oblique view showing male and female connector portions in a connected position.
FIG. 6 is a planar, cross-sectional view taken on plane 6 - 6 in FIG. 5 , but showing the male and female connectors in a disconnected position.
FIG. 7 is a planar, cross-sectional view taken on plane 7 - 7 in FIG. 5 , showing the male and female connectors in a connected position.
FIG. 8 is an enlarged view of area “ 8 ” in FIG. 7 .
DETAILED DESCRIPTION
FIG. 1 is an exploded view of a female connector 10 , according to an aspect of the invention. A plurality of conductive contact pins 28 are disposed within respective annular openings 56 formed in a main seat body 30 of female connector 10 . Conductive contact pins 28 may be spring-biased by cooperating with springs 26 and pegs 24 , which may be disposed in correspondingly-shaped recesses or cavities 36 formed in an adapter element 18 , which cooperates with the main seat body 30 via, for example, threaded fasteners 14 , to retain the pins 28 , springs 26 and pegs 24 in an assembled position. Pegs 24 may include crimped connectors to receive and secure the ends of respective conductors or wires (not shown) from an electrical source and form a conductive path with springs 24 and pins 28 . Referring additionally to FIG. 6 , pins 28 may each include a narrow forward portion and a retaining collar or shoulder such that the forward portion is narrow enough to extend into the annular opening 56 , while the retaining collar or shoulder prohibits further passage of the pin 28 into the annular opening 56 , thereby retaining the pin 28 within the main seat body 30 .
According to an aspect of the invention, pins 28 , springs 26 and pegs 24 may be replaced with pre-assembled, telescoping spring-biased contact pins 25 , which each include a spring element (not shown) disposed within telescoping conductive elements. Contact pins 25 may include any commercially available pre-assemble, telescoping contact pins suitable for use in connector environments.
According to an aspect of the invention, connector 10 may be provided with magnetic elements 20 , disposed within complementary-shaped recesses formed in adapter 18 , which may be defined between posts or grip legs 19 . Sheaths 22 enclose magnets 20 and also partially or wholly enclose the length and depth of grip legs 19 and thereby cooperate with adapter 18 , recesses and grip legs 19 to secure the magnets thereon. In accordance with an aspect of the invention, sheaths 22 may be comprised of paramagnetic or non-magnetic material, such as copper, aluminum or bronze, which has the effect of distributing the magnetic field. Also in accordance with an aspect of the invention, sheaths 22 and grip legs 19 may be dimensioned so as to provide some movement of magnets while being retained therein to provide a “floating” mount of the magnets, which enhances the magnetic forces that secure the female connector to a counterpart. Sheaths 22 are received in elongated holes or recesses 36 in seat body 30 and retained therein when the seat body 30 and adapter 18 are in an assembled state.
Housing halves 54 may be provided to enclose the assembled seat body 30 and adapter 18 and may include threaded fasteners 14 . A neck grip or tension relief collar 16 secures an electric source or target cable wire (not shown) against slippage within housing 54 and absorbs tension on the cable wire. Alternatively, housing 54 may be formed integrally with seat body 30 and adapter 18 using an injection molding process.
In accordance with an aspect of the invention, seat body 30 is provided with notch recesses 34 , which, in a connected state, may receive a complementarily-shaped projection or protuberance, such as protuberances 48 on male connector 12 ( FIG. 2 ), which provides for vertical and lateral alignment of the female connector 10 with a counterpart male connector 12 . In accordance with an aspect of the invention, seat body 30 is provided with lateral ramps or inclined surfaces 100 , which may be at a 45-degree angle, which provide for lateral alignment of the female connector 10 with a counterpart.
FIG. 2 shows an exploded view of a male connector 12 in accordance with an aspect of the invention. The male connector 12 may include a male contact plate 46 and a male foundation plate 40 , which cooperate to retain male connector magnets 21 and male conductive pins 42 therein. Male contact plate 46 includes a plurality of pinholes or annuluses 60 formed therein to receive a like plurality of male conductive pins 42 in an array, such as parallel rows. The back ends of the male pins 42 may be seated in concavities 58 in foundation plate 40 . The male pins 42 extend in a forward direction through the annuluses 60 to thereby provide a conductive path from foundation plate 40 thru contact plate 46 . Foundation plate 40 includes protuberances or raised portions 41 for supporting magnets 21 thereon. Male sheaths 44 , which may partially or completely cover or enclose magnets and secure magnets 21 against protuberances 41 , are also received in elongate openings 50 of male contact plate 46 and retained therein, also retaining magnets within the male connector 12 in an assembled state. As shown in the zoomed-in view in FIG. 2 , male magnets 21 may be oriented such that a top magnet has a north polarity facing forward, toward a male connector counterpart (not shown in FIG. 2 ), whereas a lower magnet has a south polarity facing forward, toward the male connector counterpart. Threaded fasteners 14 may secure the male contact plate 46 to the foundation plate 40 and may also secure the assembled contact plate 46 and foundation plate 40 to a male housing 38 via threaded holes 62 .
Referring additionally to FIG. 3 , according to an aspect of the invention, contact plate 46 is provided with ramped or angled surfaces 102 , which cooperate with the ramps 100 ( FIG. 1 ) on female connector body 30 , to provide for easy connection and positive alignment of the male connector 12 and female connector 10 . Protuberances 48 are also received within recesses 34 to provide for positive vertical and lateral alignment. Magnetic biasing forces are provided via female connector magnets 21 (situated behind sheath 44 in FIG. 3 ) and male connector magnets (situated behind sheath 22 in FIG. 3 ) such that the male and female connectors are magnetically attracted to one another. As will be appreciated by those of ordinary skill in the art, owing to the alignment elements, including protuberances 48 , recesses 34 , ramps 100 and surfaces 102 , as the male and female connector portions are roughly aligned by a user and put in close proximity to one another, the magnetic forces further pull the respective connectors into perfect alignment and together, without a user having to precisely align them, to a completely connected state shown in FIGS. 4 and 5 . More specifically, the physical structure of male ramps 102 and female ramps 100 prevents the male connector 12 and female connector 10 from skipping one or more magnetic peaks and valleys to the right or to the left, prior to connecting, and thus prevents male pins 42 from misalignment or improper connection with female pins 28 . The cooperating ramp surfaces 100 and 102 sets up left to right, or lateral, physical centering, for approximate guidance at a gap distance, as well as precision guidance to final plug-in and contact as the connectors move to close proximity. The ramps set up a funneling effect to channel the connectors towards each other in the correct position.
According to an aspect of the invention, vertical, or top to bottom centering, as well as proper orientation, is facilitated by the female magnets 20 and male magnets 21 , as well as the female notches 34 and protuberances 48 . With regard to orientation, the reverse polarities of the top and bottom male and female magnets results in repulsive forces if the male connector is improperly oriented, i.e., rotated 180-degrees from a proper orientation. Thus, tactile sensing of repulsive forces may indicate to a user that orientation is improper without the user having to view the actual the orientation of the connector. In this way, the user is prevented from connecting the connectors in an improper orientation. As a result, potential damage to the connector, or more catastrophic consequences, such as failure or misalignment of an electronic connector in a medical environment, is prevented. Also, in accordance with an aspect of the invention, the contact of forward surfaces of respective sheaths 44 and 42 may cause an audible signal, such as a “click,” to indicate to the user that the connector is completely connected and aligned.
FIG. 6 is a planar cross-sectional view taken along lines 6 - 6 in FIG. 5 , showing the male 12 and female 10 connectors in a disconnected configuration. It can be seen that, in the disconnected configuration, the contact pins 28 of female connector 10 extend beyond a front surface 55 of the female seat body 30 . Contact pins 28 are biased in this direction by springs 26 . Contact pins 42 on male connector 12 also extend beyond a front surface 49 of the male contact plate 46 . Thus, contact between pins 42 and pins 28 is ensured as the male and female connector portions move to a connected state. Moreover, it will be noted that the contact pins 42 do not extend significantly beyond the male contact plate, thus preventing deformation (i.e., lateral bending) or damage to the pins when exposed in the disconnected state.
FIG. 7 is a planar cross-sectional view taken along lines 7 - 7 in FIG. 5 showing the male 12 and female 10 connectors in a connected configuration. In this configuration, male connector 12 and female connector 10 are held together by magnetic forces and, as may be seen in the enlarged view in FIG. 8 , female connector contact pins 28 are pushed back into annular openings 60 by male contact pins 42 , against the biasing force of springs 26 . Forward ends of male contact pins 42 may thus extend to some degree into the annular openings 60 on the female seat body 30 . Thus, each contact pin 28 is biased into contact with a respective contact pin 42 to make sufficient electrical contact and to allow for variances in pin length or wear that may occur.
It should be understood that implementation of other variations and modifications of the invention in its various aspects may be readily apparent to those of ordinary skill in the art, and that the invention is not limited by the specific embodiments described herein. It is therefore contemplated to cover, by the present invention any and all modifications, variations or equivalents that fall within the spirit and scope of the claims that follow.
|
An electrical connector, which may be a multi-pin connector, includes magnetic elements and mechanical alignment elements which provide connective forces and precision alignment and orientation. The magnetic elements permit a user to bring male and female connector portions only into “rough” alignment before magnetic forces bring the portions into the correct position. Pin contacts on the connector portions extend only a small amount beyond respective protective annular openings and are thereby protected. Spring-biased pin elements may be included on one of the connector portions to bias the contact pins into engagement and create conductive paths when the portions are in a connected position. Paramagnetic or non-magnetic sheaths may surround the magnetic elements to focus, or distribute, magnetic forces.
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the automated control of liquid discharge from a control structure or storage reservoir, and more particularly to the controlled release of stormwater to a conveyance system from a stormwater detention reservoir or system of reservoirs by automatic adjustment of the release rate from the reservoir in order to support a variety. of water management objectives.
2. Discussion of the Problem Solved
Stormwater is water generated by rainfall and is often collected and routed into storm water management facilities to prevent downstream flooding, erosion, sedimentation and water quality degradation. Uncontrolled stormwater runoff from development, forest and agricultural activities can cause flooding, channel erosion, sedimentation and degradation of wildlife habitat and water quality.
Many urban and developed areas require stormwater management, the objectives of which include runoff rate control, erosion and sedimentation control, as well as water quality improvement. Accomplishment of these objectives is often attempted with stormwater detention reservoirs and water quality improvement structures. The term "detention reservoir," used herein, refers to a facility or structure capable of detaining, storing or withholding surface water or other liquids. This includes ponds, lagoons, below ground pipes, vaults, tanks, ditches, wetlands and tidal marshes, as well as water controlled by dams, dikes, weirs or risers.
Development can drastically change the hydrology of a site. Roads, driveways, sidewalks, roofs and lawns cause greater volumes of stormwater runoff at higher rates than under natural conditions. To control peak runoff rates from developed areas, stormwater is typically collected and routed to a detention reservoir where the stormwater is stored and released to the downstream system at a designed rate. The design release rate is often determined by the capacity of the downstream conveyance system and is frequently limited to a designated proportion of the predeveloped runoff rate. Exceeding the capacity of the downstream conveyance system can create flooding, erosion and sedimentation.
The release rate from the detention reservoir is typically controlled by a restrictor unit. Prior art restrictor units embody a flow restrictor consisting of a fixed placement flow structure such as an orifice plate, weir, gate or combination thereof. The flow restrictor is configured to release stormwater from the detention reservoir at the design release rate. Fixed placement flow restrictors are configured to discharge at the design release rate only when the detention reservoir is full. As the storage level in the detention reservoir decreases, the hydraulic head on the flow restrictor also decreases, resulting in a decrease in the release rate from the detention reservoir. Therefore, optimal use of storage volume for managing stormwater is not attained with prior art flow restrictors.
The relationship between hydraulic head and flow rate through the flow restrictor is illustrated in FIG. 1. For this illustration, the flow restrictor is a circular orifice and flow rate can be calculated with the equation: ##EQU1## Where: Q=flow rate (cubic feet/second)
D=orifice diameter (feet)
H=hydraulic head (feet)
The flow rates for four different orifice diameters with hydraulic heads varying from 0.0' to 10.0' are shown in FIG. 1. The design release rate for each orifice occurs with a hydraulic head of 10.0'. For the 0.40' diameter orifice, this rate is 2.0 CFS. With the hydraulic head at 5.0', the flow rate for the 0.40' diameter orifice decreases below the design release rate to 1.4 CFS. With prior art control structures, decreases in hydraulic head on the flow restrictor reduce discharge from the detention reservoir below the design release rate resulting in ineffective use of available storage volume because more storage volume is required to detain runoff from a storm than would be required if discharge from the detention reservoir were maintained at the design release rate for all storage levels.
Ineffective use of available stormwater reservoir volume increases the costs of construction projects. In King County, Washington, for example, a developed acre of land can require up to 15,000 cubic feet of detention volume for stormwater management. Construction costs of detention reservoirs range from $5-10/cubic foot of storage. The value of the real estate occupied by the stormwater management detention reservoir is an additional cost which may be far more significant than construction costs.
Many stormwater management systems, installed in developed areas over five years ago, no longer meet current regulatory stormwater management requirements. More restrictive release rates and more stringent water quality standards have increased the storage volume requirements for detention reservoirs. Some inadequate stormwater detention systems cannot be upgraded to meet current standards, due to space or economic constraints. Stormwater detention reservoirs are typically designed to detain stormwater from the contributing watershed for a storm event of a specified return interval. A 10-year storm event is a storm of magnitude which is likely to occur once every 10 years. Larger storm events statistically occur at less frequent time intervals. Storm events of 10, 50 or 100-year return intervals are commonly used for sizing detention reservoirs. Stormwater inflow in excess of the design capacity of the detention reservoir bypasses the flow restrictor through an overflow outlet.
A flow restrictor mechanism has the potential to be blocked or clogged by debris carded in the stormwater. Blockage of the flow restrictor mechanism can cause the detention reservoir to fill to capacity and then overflow. Overflow from detention reservoirs is not uncommon and results in significantly higher flow rates than those regulated by the flow restrictor.
The design of the detention reservoir and the flow control structure is typically based on analytical methods using hydrologic models. The accuracy of the models and procedures used in the design process varies. Once in place, there is typically no convenient method for adjusting the design of currently used flow restrictors to improve the operation of the system based on actual performance.
Prior art flow restrictors are always in an open position. No flexibility exists in providing increased detention time under conditions which so permit. As a consequence, prior art flow restrictors do not allow appreciable improvements in water quality through increased detention time.
Stormwater is often routed through a vegetated swale to remove pollutants from the stormwater. Vegetated swales function primarily by slowing stormwater flow velocity with increased flow resistance from the vegetation, thereby enabling suspended solids to settle. Vegetated swales have a mixed record of success in terms of effective stormwater pollutant removal. In many instances, poor pollutant removal capabilities have been attributed to short detention time and resuspension of trapped pollutants. Pollutants such as sediment, grease, oils, nitrates, phosphates, metals, coliform bacteria and pathogens can adversely alter the physical, chemical and biological properties of the environment and decrease water quality.
Water management on agricultural and forest land is commonly practiced to improve soil moisture conditions for machine operations (such as planting and harvest) and plant growth. Controlling drainage rates from agricultural and forest land is considered to be a "Best Management Practice." Controlled drainage allows water tables to be managed more precisely, providing greater control over outflow rates and improving water quality. The benefits of controlled drainage are realized offsite through reduced peak flow rates and improved water quality. Onsite benefits include improved crop yields and improved soil operability. As with stormwater management systems, prior art fixed placement flow restrictors are typically used in agricultural and forest water management applications, often limiting the flexibility of water management alternatives.
Constructed wetlands are becoming a common means to mitigate losses of natural wetlands, manage stormwater, protect coastlines from erosion and enhance wildlife habitat. The successful design and implementation of constructed wetlands depend to a large extent on the site hydrology. With prior art fixed placement flow restrictors, maintaining desired plant species composition and wetland bathymetric conditions are often difficult tasks when constructing wetlands. It has been documented that approximately half of the constructed wetlands fail, primarily due to a lack of adequate control over the hydrology. At an average cost of $70,000/acre, construction of wetlands can be a significant project expense.
Construction and rehabilitation of tidal wetlands and marshes are increasingly more common methods of protecting coastal areas from erosion and enhancing wildlife habitat. The success of tidal wetlands in supporting a desired type of vegetation and wildlife relates to the hydroperiod and tidal fluctuations of the wetland. Plant species found in high marsh ecosystems may be desired in a specific constructed tidal marsh site, but existing tidal fluctuations or hydroperiod may prevent the establishment and success of such species.
Prior art flow control structures are limited in their effectiveness in managing stormwater and achieving other water management objectives. A system is needed which has the versatility to meet a variety of stormwater management objectives including making more effective use of available reservoir storage volume, improving water quality through increased detention time, routing stormwater, controlling wetland hydroperiod and improving agricultural and forest water management. In addition, a system is needed which allows site specific adjustment and refinement of operation.
OBJECTS OF THE INVENTION
An object of the invention is to improve the methods of stormwater, agricultural, wetland and tidal marsh water management. Another object of the invention is to provide more flexible and precise control over discharge of stormwater from a stormwater detention reservoir. Still another object of the invention is to provide a more effective means than prior art in controlling the rate and sequence of stormwater discharge from a stormwater detention reservoir. Still another object of the invention is to provide a constant discharge rate from the detention reservoir as the hydraulic head on the flow restrictor decreases, thereby minimizing required storage volume. An additional object of the invention is to improve the performance of inadequately designed existing stormwater detention systems without increasing the storage capacity of the reservoir. A further object of the present invention is to increase average detention time of first-flush and low volume stormwater inflows, thereby allowing more settling of suspended solids from the stormwater and improving water quality. A still further object of the invention is to provide an improved detention method to decrease the potential for overflow from a stormwater detention reservoir, thereby minimizing the occurrence of high discharge rates. Another object of the invention is to provide a flow control system which automatically clears the flow restrictor mechanism when blocked by foreign debris, thereby reducing risk of overflow and reducing manual maintenance. Still another object of the invention is to provide a flow restrictor mechanism that can be configured on a site specific basis with computer software as opposed to the conventional process of physical lubrication, allowing the invention to be used on any site and the refinement of installations to be based on actual performance. Still another object of the invention is to collect discharge rate and storage level data for evaluating the performance of the system in meeting desired water management objectives. A further object of the invention is to provide a means for allowing the stormwater detention reservoir to be used as a storage facility for irrigation water on a seasonal basis. A still further object of the invention is to allow more flexible and precise water management in agricultural and forest drainage systems. And another object of the invention is to provide a flexible and automated means to regulate constructed wetland surface water inflow and outflow, thus controlling the hydroperiod in those wetlands. Still another object of the invention is to allow regulation of tidal fluctuation, water level and hydroperiod in tidal marshes, allowing constructed tidal marshes to function as designed in terms of providing stormwater management control, erosion protection and wildlife habitat.
SUMMARY OF THE INVENTION
According to the present invention, the foregoing and other objects are attained by providing a control system to regulate liquid flow using a mechanical system driven by microprocessor programs. The control system includes an adjustable flow restrictor mechanism, a sensor, a microcontroller, microprocessor programs and an actuator. The adjustable flow resistor mechanism physically controls liquid flow. The sensor monitors environmental parameters and sends signals to the microcontroller. The microcontroller interprets the signals and applies microprocessor programs to control liquid flow by adjusting the flow control mechanism using the actuator.
The current invention provides more flexible and precise flow control than prior art. In the application of stormwater management, the invention dictates lower storage volume requirements and provides greater detention time for storm events where water quality is of highest concern.
The current invention allows the design release rate to be maintained for all storage levels in the reservoir. This is accomplished with the interactive combination of adjustable flow restrictor mechanism, sensor, microcontroller, microprocessor programs and actuator. The adjustable flow restrictor mechanism is operated by an actuator under the control of a microcontroller using microprocessor programs and data from one or more sensors. By increasing the orifice diameter to compensate for the decreases in hydraulic head, as shown in FIG. 2, a constant flow rate can be maintained. Using a 2.0 CFS design flow rate as an example, the orifice diameter is 0.40' when the reservoir is full. When the hydraulic head is 5.0', the corresponding orifice diameter is 0.48'. Maintaining the design release rate for all reservoir storage levels, as in the current invention, requires less storage volume to detain runoff from a given storm in comparison to prior art flow restrictors.
The current invention provides the ability to economically upgrade existing stormwater management systems which are not operating at current regulatory standards. As previously described, the invention makes more effective use of detention reservoir storage volume, thus many existing undersized detention reservoirs could be modified to perform at current standards if retrofitted with the flow control system. With more precise flow control, as offered by the current invention, existing stormwater detention reservoirs could perform more effectively. Watersheds with stormwater management facilities having few or no features for water quality improvement could additionally benefit from the current invention.
The invention can be programmed and installed to minimize the occurrence of reservoir overflow. One method in which this can be accomplished is by implementing sensors to sense conditions indicative of the rate of change of the storage level. If the reservoir is near capacity and the rate of inflowing water is apt to create overflow conditions, the microcontroller instructs the actuator to adjust the flow restrictor mechanism to increase the rate of flow. The incremental flow released to prevent overflow is at a rate less than that likely to occur in the event of overflow.
The current invention allows the flow restrictor mechanism to clear itself of debris. When conditions indicative of debris blockage are monitored, the microcontroller instructs the actuator to oscillate the flow restrictor mechanism between the open and closed positions to dislodge debris from the flow restrictor mechanism. Alternatively, the microcontroller can routinely instruct the actuator to oscillate the flow restrictor mechanism on a calender schedule.
The current invention allows adjustment of the flow restrictor mechanism to refine initial designs based on actual performance. The microcontroller can be programmed to collect various types of data useful in evaluation of the performance of the installed invention. Data such as storage depth and corresponding flow restrictor mechanism flow area can be used to calculate discharge rate from the detention reservoir over time. Inadequacies in flow restrictor design or control logic in operating the mechanism can be identified and corrected with automated or interactive onsite programming of the microcontroller. In addition, interactive adjustment of the flow restrictor mechanism through computer software allows the same flow control system to be used for a variety of sites and conditions.
The current invention provides opportunity for greater stormwater quality improvement over conventional flow control structures and vegetated swales. Substantial gains in water quality improvement can be achieved by detaining low volume storm events and first-flush runoff volumes for longer periods of time. Longer detention time allows suspended solids in the stormwater, which carry pollutants, to settle to the bottom of the detention reservoir. First-flush runoff occurs with the onset of storm events. Longer detention of first-flush runoff is important because this stormwater carries relatively high concentrations of pollutants which have accumulated on the impermeable portions of the watershed surface since the previous storm event. The flow control system can be programmed to identify low volume storm events and first-flush runoff volumes and provide longer detention time. The invention provides longer detention time by decreasing or completely closing the flow restrictor mechanism flow area. Detention time with the current invention can be increased from a matter of hours, as with prior art, to several days. Knowledge of seasonal rainfall patterns can be used in the control logic to further improve peak runoff rate control and water quality. The invention can be installed in construction sedimentation ponds to improve the quality of water leaving the site by maximizing detention time and allowing the solids from the turbid water to settle.
The invention can be configured to turn stormwater detention reservoirs into irrigation sources. This is accomplished by closing the flow restrictor mechanism and holding back stormwater when irrigation demands are high. Water held in the storage reservoir is then available as an irrigation source for a pump driven irrigation system.
From the preceding discussion, it is evident that the present invention can improve stormwater management for an individual detention reservoir. On a district or regional scale, downstream flooding, erosion and sedimentation problems could be improved with controlled stormwater routing as provided by the current invention. A drainage basin is typically comprised of one or more contributing watersheds which combine in the downstream conveyance system. By managing stormwater from individual watersheds in coordination with one another, downstream available conveyance capacity can be used most efficiently, thus minimizing flooding and erosion hazards. A network of detention reservoir flow control systems can be linked to a central controller which monitors downstream conveyance capacity as well as available stormwater storage capacity in the network of detention reservoirs. The central controller can be programmed to schedule stormwater release. The central controller operates under the constraints of minimizing overflow in the reservoirs and not exceeding downstream conveyance capacity. Thus the central controller regulates the detention reservoir flow control systems based on the reservoirs available storage volume and the available downstream conveyance capacity.
The current invention provides more flexible and precise water management for agricultural and forest watersheds than prior an flow restrictors. One application of the current invention includes programming the microcontroller to automatically control drainage rates in a manner which will maintain improved soil moisture conditions for crop growth by automatically adjusting the level of water in the drainage ditches to a level most appropriate to the growth stage and water demands of the crop. This water level may vary seasonally and with different meteorological conditions.
The current invention allows improved control over constructed wetland inflow and outflow of water and can be used to create or reduce variations in hydrologic conditions on a site specific basis. In addition, seasonal variations in hydrology can be automatically controlled, thus ensuring that the constructed wetland will function as designed.
The current invention allows control over tidal marsh water levels, hydroperiods and tidal fluctuations. With knowledge of the tidal patterns and stage-storage relationship of the wetland site, the hydrology of the tidal wetland can be manipulated to create either a high marsh or low marsh ecosystem.
BRIEF DESCRIPTION OF VIEWS
FIG. 1 is a graph illustrating the relationship between hydraulic head on a fixed placement flow restrictor and the resulting flow rate through the mechanism. The relationship is shown for four different diameter orifices, each for hydraulic heads ranging from 0.0' to 10.0'.
FIG. 2 is a graph illustrating the orifice diameter required to maintain a constant discharge rate from a flow restrictor mechanism under variable hydraulic head. Four different flow rates are presented for hydraulic heads ranging from 0.0' to 10.0'.
FIG. 3 is a schematic view of a developed watershed showing a system in which stormwater is collected, conveyed, detained and released to a downstream channel.
FIGS. 4 and 5 show plan and cross sectional views of a typical stormwater detention tank and a stormwater control system according to the invention, illustrating one application for the use of the invention.
FIG. 6 presents details of the control structure and restrictor trait shown in FIG. 5.
FIGS. 7 and 8 are enlarged elevations showing the adjustable gate valve for the flow control mechanism shown in FIG. 5, and also showing a sensor, microcontroller and actuator.
FIGS. 9 and 10 are plan and front schematic views of a generalized configuration of an alternative embodiment of the invention.
FIG. 11 is a logic diagram for flow rate control from a stormwater detention reservoir.
FIG. 12 is a logic diagram for automated clearing of debris from the flow control mechanism.
FIG. 13 is a logic diagram for data collection and automated stormwater system performance evaluation and adjustment.
FIG. 14 is a schematic view of a region where stormwater flow to a downstream system from two separate watersheds is managed with a flood routing system according to the invention.
FIG. 15 is a logic diagram for routing stormwater from two reservoirs discharging into a common downstream channel with limited conveyance capacity.
FIG. 16 is a profile view of a typical agricultural/forest drainage system and illustrates the use of the invention in the drainage system.
FIG. 17 is a profile view of a constructed tidal marsh and illustrates the use of the invention in the system and the range in tidal fluctuations.
FIG. 18 is a graph illustrating the tidal fluctuations for a constructed tidal marsh under unregulated tidal conditions and under conditions regulated by the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIGS. 3-5, stormwater from a watershed is collected by a series of interconnected catch basins 20 and is routed through a conveyance system 22. The stormwater enters a detention reservoir 24 through a reservoir inlet pipe 26 and is stored in the detention reservoir 24. A connector pipe 28 conveys the stormwater from the detention reservoir 24 to a control structure 30. Discharge from the detention reservoir 24 is regulated in the control structure 30. Stormwater leaves the control structure 30 through an outlet pipe 32 and is conveyed to a downstream system 34. Maintenance access to the detention reservoir and the control structure is provided by maintenance entrances 35.
The control structure 30 shown in FIG. 5, includes a flow restrictor mechanism, such as a gate valve 36, shown enlarged in FIG. 6, which regulates the outflow of stormwater from the system. Intowing stormwater in excess of the capacity of the detention reservoir 24 bypasses the flow restrictor mechanism 36 through an overflow outlet 38 when the water level rises above the level of the outlet 38 and exits the control structure 30 through the outlet pipe 32 to the downstream system 34.
The flow restrictor mechanism 36 is attached to a restrictor unit 40 by a fixed collar and gasket 42. The collar is sized to be easily installed on the restrictor unit 40. The gasket provides a watertight seal for the fitting. The restrictor unit 40 provides a structural platform for the flow restrictor mechanism 36, overflow outlet 38 and outlet pipe 32. The fixed collar and gasket 42 provide a means to attach the flow restrictor mechanism 36 to the restrictor unit 40. A bottom mount 44 securely fastens and supports the flow restrictor mechanism 36 within the control structure 30. The flow restrictor mechanism 36 regulates the discharge rate of liquid from the control structure 30 and detention reservoir 24. The flow restrictor mechanism 36 is mechanically adjustable by raising and lowering a drive stem 52. As shown in FIGS. 7-8, a valve body 46 encloses an adjustable gate 48. The gate 48 is connected to an actuator, such as an electric motor 50, by the drive stem 52. The electric motor 50 contains a position indicator to maintain the relative position of the gate 48 and thus the flow restrictor mechanism 36 flow area. The drive stem 52 passes through an offset yolk 54 which provides rigidity during operation of the gate 48 adjustment. A wall brace 56 provides guidance for the drive stem and additional support and rigidity for the flow restrictor mechanism 36. The offset yolk 54 and wall brace 56 each contain a bushing 58, through which the drive stem 52 passes. A gearing assembly inside the motor 50 operates on the stem threading 60, thus raising or lowering the drive stem 52, thereby adjusting the gate 48 position within the port opening 62 of the flow restrictor mechanism 36. A handwheel 64 is connected to the gearing assembly of the motor 50 to allow manual adjustment of the gate 48. A top brace 66 secures the motor 50 to the control structure.
The degree of closure of the gate 48 is determined by a signal sent from a position indicator on the electric motor 50 to a microcontroller 68. The motor 50 is controlled by instructions from the microcontroller 68 which precisely adjusts the flow restrictor mechanism 36. An electric utility box 70 provides housing for power connections to the motor 50 and the microcontroller 68. An actuator power cable 72 from the electric utility box 70 connects to the motor 50. A microcontroller power cable 74 from the electric utility box 70 connects to the microcontroller 68.
The microcontroller 68 is a digital/analog unit consisting of prior an components to perform digital control, automated analog measurement, equipment monitoring, switch monitoring, sensor monitoring, personal computer interface, telecommunication interface and data acquisition. The microcontroller 68, as such, is configured with the following features: CMOS microprocessor, RS-232 ports, on-board computer language interpreter, memory, on-board EPROM programmer, programmable counters/timers, external interrupts, printer interface, real-time calender clock, display module and interface and analog-digital converter. A power connection 76 as well as telecommunications and computer interface connections 78 are located on the body of the microcontroller 68. Instrument cables 80 and 80' connect the microcontroller to the motor 50 and to a sensor such as an ultrasonic water level sensor 82. Microprocessor programs for setting the flow restrictor mechanism 36 degree of closure are programmed into the microcontroller 68. The microprocessor programs incorporate the decision logic which allows the flow control system to meet various water management objectives for each particular installation as will be described below. The microcontroller 68 can be operated in three alternative modes including monitoring mode, interactive mode and hardwired mode.
When the microcontroller 68 operates in the monitoring mode, microprocessor programs use data based on external environmental parameters such as rainfall rate, rainfall amount, reservoir storage level or storage volume rate of change. The sensor measures the parameter of interest, such as reservoir storage level, and is monitored by the microcontroller 68. The microcontroller 68 interprets signals from the sensor, and based on the management objectives, selects the appropriate degree of closure for the flow restrictor mechanism 36 flow area which is mechanically set by the motor 50.
Generalized schematic representations of an alternative embodiment are shown in FIGS. 9-10, where the actuator 84 can be an electric motor, air, fluid or manually powered operator which controls a flow restrictor mechanism 86, which can be an adjustable gate, valve or orifice. As discussed above, control of the flow restrictor mechanism 86 is based upon microprocessor programs in a microcontroller 88. Real time environmental variables are measured with a sensor 90. The sensor 90 is monitored by the microcontroller 88. The sensor 90 may be a submerged pressure transducer, ultrasonic sensor, float and pulley/potentiometer sensor, dipping probe sensor, bubbler sensor, rain gauge, flow velocity meter, volumetric flow meter upstream or downstream from the reservoir, soil moisture meter or other such instrument for measuring environmental parameters.
Stormwater management objectives including constant discharge under variable hydraulic head, water quality improvement through increased detention time, reduced turbidity in stormwater exiting sedimentation ponds, improvement in the performance of existing undersized detention reservoirs, minimization of overflow from detention reservoirs, automated clearing of debris from the flow restrictor mechanism, flow data acquisition, stormwater routing, agricultural and forest drainage control, wetland hydroperiod and water level regulation and coastal marsh tidal fluctuation regulation are best accomplished with the microcontroller operating in the monitoring mode. A description of the method of accomplishing each of these stormwater management objectives follows.
Referring to FIGS. 4-8, to maintain constant discharge from the control structure 30 under variable hydraulic head (i.e. constant flow from the detention reservoir 24 for different reservoir storage levels), the sensor 82 is used to sense detention reservoir 24 storage level. The microcontroller 68 monitors the sensor 82 on a specified time interval and translates the signal from the sensor 82 into a detention reservoir 24 storage level depth, which is equated to hydraulic head on the port opening 62 of the gate valve 36. A microprocessor lookup table program determines the appropriate opening of the flow restrictor mechanism 36 to maintain the design release rate. The degree of the flow restrictor mechanism 36 opening is maintained in program memory of the microcontroller 68 or referenced directly from the flow restrictor mechanism 36 or motor 50 by an electronic position indicator. The required adjustment in the flow restrictor mechanism 36 flow area is determined by the microcontroller 68. A signal is sent from the microcontroller 68 to the motor 50 to adjust the flow restrictor mechanism 36 to the desired position. For example, when the rate of intowing stormwater to the detention reservoir 24 is greater than the design release rate, storage level in the detention reservoir 24 increases, thus increasing hydraulic head on the flow restrictor mechanism 36 port opening. The microcontroller 68 receives a signal from the sensor 82, indicating a change in storage level and determines the new smaller required opening of the flow restrictor mechanism 36. The microcontroller 68 then sends a signal to the motor 50 to physically set the flow restrictor mechanism 36 to the required opening to maintain the outflow through the outlet pipe 32 at the design release rate. A logic diagram for flow rate control from the detention reservoir 24 is illustrated in FIG. 11.
To improve water quality through increased detention time of stormwater, the sensor 82 is used to sense conditions indicative of detention reservoir 24 storage level and storage level rate of change. In FIG. 6, the ultrasonic water level sensor 82 can be used to measure reservoir storage level. Measurements taken over time can be used to measure storage level rate of change. Computer programs for maximizing detention time and therefore increasing settling of suspended solids, can be adopted on a site specific basis having knowledge of the watershed's hydrograph characteristics in response to rainfall events. The rate of change of storage level can be used to indicate the start and end of storm events. The microcontroller 68 monitors the sensor 82. The start of a rainfall event is indicated by a change in reservoir storage level as measured by the sensor 82. The microcontroller 68 operates a program which determines available storage volume in the detention reservoir 24. If adequate storage volume exists, the microcontroller 68 sends a signal to the motor 50 to close the flow restrictor mechanism 36. If the intowing stormwater ceases, as indicated by the change in detention reservoir 24 storage level, before a predetermined extended detention storage level is reached, the flow restrictor mechanism 36 remains closed until either a predetermined detention time has passed or intowing stormwater once again begins and the extended detention storage level is reached. The extended detention storage level is determined analytically by hydrologic simulation or through field testing. The extended storage level is intended to provide adequate storage volume for intowing stormwater in addition to that volume of stormwater which is being detained for an extended period. When the extended detention storage level is reached with the flow restrictor mechanism 36 in the closed position, the microcontroller 68 sends a signal to the motor 50 to open the flow restrictor mechanism 36 to discharge stormwater. The management objective is to discharge stormwater at a rate which will maximize detention time but not create reservoir overflow. A logic diagram for controlling stormwater detention time is illustrated in FIG. 11.
An alternative method of sensing the characteristics of a rainfall event is to use an electronic rainfall gauge as a sensor. The rainfall gauge senses the onset, cessation, rate and amount of rainfall. With knowledge of the water yield characteristics of the watershed, the microcontroller 68 can be programmed to calculate the anticipated intowing hydrograph of the rainfall to the detention reservoir 24. This process of predicting intowing hydrographs is routinely followed in designing stormwater detention reservoirs with analytical methods such as the Soil Conservation Service hydrograph method or the Santa Barbara Urban Hydrograph analysis method. With an estimate of the intowing hydrograph, the microcontroller 68 can adjust the flow restrictor mechanism 36 to optimize detention time of intowing stormwater.
To reduce the turbidity of the stormwater exiting from sedimentation ponds, methods similar to those for increasing water quality through increased detention time are employed. The reservoir storage depth at which the flow restrictor mechanism 36 is allowed to remain in the closed position and desired detention times may vary depending upon the characteristics of the suspended solids. For instance, longer detention time would be required for sealing freer or less dense suspended solids. As an alternative to detention time as a measure of water quality improvement, a turbidity meter could be used as a sensor, monitored by the microcontroller 68. The turbidity meter would indicate when the turbidity of the detained stormwater is reduced to a desired level and thus could be released from the detention reservoir 24. The release of stormwater from sedimentation ponds can be controlled interactively on a day to day basis, thus allowing weather forecasts to be used to advantage in providing maximum detention. The weather forecast could be used to maximize detention time of the stormwater with decreased risk of detention reservoir 24 overflow. If, for example, no rainfall is anticipated to occur for the next several days, stormwater could be detained with low risk of detention reservoir 24 overflow. However, if rainfall is anticipated to occur in the near future, stormwater currently being detained in the detention reservoir 24 may best be released from the reservoir 24 to provide storage volume for expected stormwater inflow.
To improve the performance of existing undersized stormwater detention reservoirs, the flow control system is retrofitted to the control structure 30 of the existing reservoir 24. Methods to maintain constant discharge from the control structure 30 under variable head, as discussed above, are employed. This increases the effective storage volume of the existing reservoir 24 by making better use of the available storage volume. In addition, methods to increase detention time, as discussed above, can be utilized to improve stormwater quality discharged from systems which may have no provisions for water quality treatment.
To minimize overflow from the detention reservoir 24, the sensor 82 is used to sense conditions indicative of detention reservoir 24 storage level and storage level rate of change. The microcontroller 68 monitors the sensor 82 for indication when the reservoir 24 store level is at a predetermined warning level below the overflow outlet 38. When this warning level occurs and the rate of stormwater inflow is greater than the rate of stormwater outflow, the microcontroller 68 sends a signal to the motor 50 to incrementally increase the flow restrictor mechanism 36 flow area to a setting which increases flow above the design release rate but at a rate less than would occur with overflow. The rate of stormwater outflow is calculated with the relationship between the hydraulic head on the flow restrictor mechanism 36 and flow area. When the detention reservoir 24 storage level has drained back down to below the warning level, as indicated by the sensor 82, the microcontroller 68 instructs the motor 50 to adjust the flow restrictor mechanism 36 such that the design flow ram is resumed. A logic diagram for minimizing overflow from the detention reservoir 24 is illustrated in FIG. 1.
To provide automated clearing of debris from the flow restrictor mechanism 36, one or more sensors are used to sense conditions indicative of a clogged flow restrictor. This is accomplished with independent sensors to measure the storage level in the reservoir 24 and the rate of intowing stormwater. If, for instance, over a time interval the storage level of the reservoir 24, as measured by the ultrasonic water level sensor 82, does not change by the differential amount of the inflow rate as measured by a flow meter at the detention reservoir inlet pipe 26 and the calculated outflow rate as determined by the flow restrictor mechanism 36 flow area, then this indicates that the flow restrictor mechanism 36 is clogged. Upon receiving a signal that indicates debris blocking the flow restrictor mechanism 36, the microcontroller 68 sends instructions to the motor 50 to oscillate the flow restrictor mechanism 36 between open and closed positions to dislodge the debris. A logic diagram for automated clearing of debris is shown in FIG. 12.
To acquire flow data, which can be used to evaluate and fine-tone the performance of the flow restrictor mechanism 36 and microcontroller 68 logic, a sensor is used to sense conditions indicative of one or more of the following: detention reservoir 24 storage level, flow rate leaving the detention reservoir 24, flow rate entering the detention reservoir 24 and rainfall. The ultrasonic sensor 82 can be used to directly measure detention reservoir 24 storage level. The relationship between reservoir storage level and flow restrictor mechanism 36 flow area can be used to calculate outflow rate from the reservoir 24. The detention reservoir storage level measured over time along with the relationship between reservoir storage level and reservoir storage volume can be used to calculate inflow rate to the detention reservoir 24. Alteratively, a flow meter in the inlet pipe 26 to the detention reservoir 24 can be used to directly measure inflow rate. An electronic rainfall gauge can be used to measure rainfall, which is useful to evaluate the performance of the system. The microcontroller 68 monitors the sensors and records the signals in microcontroller 68 program memory at a specified time interval. The collected data can be used by computer programs to automatically evaluate stormwater management performance and adjust the design of the flow restrictor mechanism 36. A logic diagram for data collection and automated evaluation and adjustment of the stormwater system is illustrated in FIG. 13. As an alternative to automated analysis and adjustment, the microcontroller 68 can be linked to a personal computer and the data downloaded and separately analyzed in an interactive mode.
To optimize stormwater routing within a region comprised of at least one detention reservoir with discharge controlled by the flow control system, a sensor is used to sense conditions indicative of storage level of the detention reservoir, storage level ram of change, discharge rate from the detention reservoir and available downstream conveyance capacity. An example where stormwater from two managed watersheds contribute to the same downstream system is illustrated in FIG. 14. Stormwater collected from a watershed is conveyed by a pipe 91 to a below ground detention reservoir 92. Stormwater collected from a second watershed is conveyed by a pipe 93 to an above ground detention reservoir 94. Control structures 96 and 98 embody separate flow control systems consisting of the previously described flow restrictor mechanism 36, motor 50, sensor 82 and microcontroller 68. A central controller 100 links flow control system microcontrollers either by direct cable or telecommunications linkage 102. Either the microcontroller in the control structure 96 of the below ground detention reservoir 92 or the control structure 98 of the above ground detention reservoir 94 could be configured to be the central controller 100. In this example, the microcontroller in the control structure 98 regulating discharge from the above ground detention reservoir 94 is configured to be the central controller 100. The central controller 100 schedules stormwater release from the individual reservoirs 92 and 94 in a manner such that efficient use is made of the conveyance capacity of the downstream system 104. A sensor such as a float and pulley/potentiometer 108 indicating available downstream conveyance capacity is linked to the centralscontroller 100 either by direct cable 106 or telecommunications linkage. The central controller 100 determines available conveyance capacity of the downstream system 104. The maximum conveyance of the downstream system is limited by the hydraulic capacity of the channel. The available conveyance capacity of the downstream system is the difference between the maximum conveyance and the current conveyance. The current conveyance is predicted knowing the channel water level as measured with the downstream water level sensor 108. Commonly applied channel flow equations are used to develop the relationship between channel water level and conveyance. If the discharge from the contributing detention reservoirs 92 and 94 is greater than the available conveyance capacity of the downstream system 104 then the central. controller 100 prioritizes discharge from the detention reservoirs 92 and 94. For instance, a detention reservoir 92 or 94 near capacity with intowing stormwater has higher -priority for discharge than a detention reservoir 92 or 94 near capacity without intowing stormwater or a detention reservoir 92 or 94 not near capacity with intowing stormwater. To control stormwater discharge, the central controller 100 sends instructions to the microcontroller regulating the discharge from the individual detention reservoirs 92 and 94. The instructions dictate the allowed discharge rate from the detention reservoirs 92 and 94 for the current flow conditions. The instructions are processed by each microcontroller which relays instructions to the motor 50 to adjust the flow restrictor mechanism 36 accordingly for the desired flow rate. A logic diagram for stormwater routing is illustrated in FIG. 15.
An agricultural or forest drainage system is illustrated in FIG. 16, where parallel drainage ditches or subsurface drains 110 remove excess water from a crop growing area 112. A collector ditch or drainage pipe network 114 collects and routes drainage through a connector pipe 28 to the flow control structure 30. The flow control structure 30 regulates water level in the collector ditch 114 and therefore water table level in the crop growing area 112. Water released through the control structure 30 is discharged through the outlet pipe 32 to an outlet ditch 116. The flow control system can be programmed to meet a variety of water management objectives which may be directed at improving soil moisture conditions for plant growth and machine operations or minimizing offsite impacts from surface water runoff.
To regulate the hydroperiod and water levels in constructed wetlands the control structure 30 is located at the inlet or outlet of the wetland. The ultrasonic sensor 82 is used to sense conditions indicative of wetland water level or water level rate of change. The microcontroller 68 monitors the sensor 82 on a predetermined time interval. A microprocessor program compares the current wetland water level to the water level which is required to maintain a desired hydroperiod. The microcontroller 68 sends instructions to the motor 50 to adjust the flow restrictor mechanism 36 in a manner such that the wetland water level is controlled to match the desired hydroperiod as closely as possible. For example, if a constructed wetland has a stream intowing at a constant rate, fluctuations in wetland water level can be created by controlling the outflow rate from the control structure on a time schedule. In contrast, if a wetland has a stream intowing at a variable rate, fluctuations in wetland water level can be minimized by controlling the outflow rate from the wetland relative to the wetland water level and water level rate of change as measured by the sensor 82.
The flow control system can be used to manage tidal fluctuations in coastal marshes in a manner similar to that used in regulating wetland hydroperiod. A primary difference is that, in the coastal marsh, the flow control structure 30 becomes both the inflow and outflow regulator of the marsh according to whether the tide is in flood or ebb stage. A design for a tidal marsh 118 constructed in a natural inlet to existing shoreline is illustrated in FIG. 17. A constructed seawall 120, built between the tidal body of water 122 and the tidal marsh area 118 contains the control structure 30. The control structure 30 regulates tidal marsh outflow through the control structure outlet 32 and tidal marsh inflow through the control structure inlet 28. The system allows the tidal marsh water level to be maintained at any desired level between the elevation of low tide 124 and the elevation of high tide 126. By synchronizing tidal marsh inflow with high tides and outflow with low tides, tidal fluctuations, marsh water levels and hydroperiod can be controlled. The tidal fluctuations under unregulated conditions and under the regulation of the current invention are illustrated in FIG. 18. Natural tidal fluctuations 128 can be regulated to produce tidal fluctuations characteristic of a low marsh ecosystem 130 or a high marsh ecosystem 132. Restricting inflow to the tidal marsh during flood tide reduces peak water levels in the marsh. Restricting outflow from the tidal marsh during ebb tide increases water levels in the wetland over natural conditions. Such control over tidal fluctuations can be critical in controlling the marsh hydroperiod for the establishment and success of a desired type of ecosystem.
As previously discussed, the microcontroller 68 can be programmed to operate in an interactive mode. This mode of operation is useful for design adjustments of the flow restrictor mechanism and control logic. The RS-232 port 78 and supporting software allow a personal computer to interface with the microcontroller 68. Data such as reservoir inflow rate, outflow rate, storage level and rainfall amounts measured with previously described sensors and stored in memory of the microcontroller 68 can be analyzed with personal computer software to evaluate the performance of the system. Necessary adjustments to improve performance can be made interactively with personal computer software which modifies the operation of the microcontroller 68. For instance, if upon evaluation of the collected dam, it is evident that reservoir storage volume is undemtilized, even for large storms, then flow rates from the detention reservoir 24 can be reduced and detention time increased to improve management of the stormwater. Or, in contrast, if the collected data shows overflow from the reservoir occurred several times, then this indicates that the logic controlling detention time and/or overflow minimization needs to be modified.
Lastly, the microcontroller 68 can be programmed to operate in a hardwired mode. In this mode of operation, the microprocessor programs base flow control on real-time scheduled calender events or programmed instructions independent of external environmental conditions. This may include instructions to adapt the stormwater detention reservoir into an irrigation source for lawn and landscaped areas on a seasonal basis by closing down the flow restrictor mechanism 36, when irrigation demands are high.
Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described therein.
|
Stormwater from a watershed is collected in a stormwater collection basin for water quality improvement primarily by settling of suspended solids, and also for control of the flow rate through downstream flow channels. The outflow rate from the basin is governed by an adjustable water control device such as a gate valve operated by a motor under control of a microprocessor in accordance with predetermined conditions as sensed by sensors such as basin water level sensors, upstream flow or rainfall sensors, and flow rate sensors downstream of the basin. The effective capacity of the basin is increased by the ability to interactively adjust the flow rate from the basin based on sensor inputs indicative of anticipated inflow rates and the flow capacity of the downstream channels and water can be retained in periods of dry weather for irrigation and the like.
| 4
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of prior German Patent Application No. 10 2015 110 226.9, filed on Jun. 25, 2015, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present disclosure relates to an electrical contact having a fixed and a movable contact part in a metal housing, for which a cleaning system is being introduced.
BACKGROUND
[0003] DE 10 2015 104 377 discloses an electrical contact in which a fixed and a movable contact part can be connected to each other via a large contact surface. The two contact parts are disposed within a metal housing and pressed against each other by way of a leaf spring. It is furthermore disclosed how the two contact parts can be locked with respect to each other by way of a metal pin. However, the contact includes a variety of drawbacks. For example, dirt particles, which are introduced via the contact surfaces of the contact parts or develop during operation of the contact, compromise the contact quality over time.
[0004] DE 4 220 716 A1 and DE 10 2014 115 745 A1 disclose sealing lips, which may also have a cleaning effect. However, while these lips keep a cable insulation or insertion socket clean, they do not clean the contact surface.
SUMMARY
[0005] Embodiments of the present disclosure provide a cleaning system for an electrical contact.
[0006] The electrical contact according to the present disclosure contains a metal housing and a fixed contact part, which is attached to the metal housing and has a contact surface, which during the attachment is located within the metal housing, and a contact tab located outside the metal housing. The electrical contact furthermore contains a movable contact part, which can be inserted into the metal housing and thus forms an electrical contact together with the contact surface of the fixed contact part. The cleaning system is introduced in that a surface of the fixed or movable contact part which establishes the electrical contact forms a profile having low-profile and high-profile portions. Scraping edges are disposed between the low-profile and high-profile portions. The scraping edges are angled less than 90° with respect to an insertion direction of the movable contact part and define a profile formed of rhombi.
[0007] In embodiments of the present disclosure, during the first insertion of the movable contact part, dirt particles stemming from the production of the contact part or the transport are removed, or at least the number of dirt particles is reduced. In this way, the electrical contact may have a cleaned contact and a lower contact resistance starting with the first use. This may be useful for high-current contacts.
[0008] In embodiments of the present disclosure, the rhombic shape in the profile does not significantly increase a required insertion force for the movable contact part and facilitates the removal of the dirt particles.
[0009] In embodiments of the present disclosure, a second dirt reservoir, which can accommodate a large number of dirt particles, is formed between the low-profile and high-profile portions of the surface. The second dirt reservoir can have a width of 0.2 to 1 mm, and preferably approximately 0.5 mm, and a depth of 0.3 to 1.2 mm, and preferably approximately 0.8 mm, for this purpose. This profile may simplify the manufacturing process and may accommodate any accumulating larger dirt particles without impairing the contact surface.
[0010] In embodiments of the present disclosure, the ratio of the required insertion force to the removal of dirt particles is optimal at an angle of 15 to 45°, and in particular at an angle of 30 to 40°, of the scraping edges relative to the insertion direction.
[0011] According to an embodiment of the present disclosure, the profile includes a plurality of rhombi, wherein the rhombi have a larger length than width in the insertion direction. This may also ensure that a large number of scraping edges is available for cleaning.
[0012] In embodiments of the present disclosure, the second dirt reservoir is formed by multiple gaps, which divide the profile in a rectilinear manner and have sharp edges with respect to the contact surface. As a result of the sharp-edged design, it is possible to easily separate oxide particles and surface impurities.
[0013] In embodiments of the present disclosure, the profile is disposed on the contact surface of the fixed contact part. When installed, the fixed contact part is typically disposed beneath the movable contact part, so that the dirt particles cannot fall out of the dirt reservoir and onto the contact surface.
[0014] In embodiments of the present disclosure, chamfers on narrow sides and deburred edges on broad sides may be provided as insertion aids within the profile. The production may be cost-effective when the profile is created by way of embossing and stamping. If the low-profile portions of the profile have a smaller surface than the high-profile portions, the use of the cleaning system reduces the contact surface only marginally.
[0015] In embodiments of the present disclosure, a further cleaning system is introduced in that at least one further scraping edge is provided near the contact surface, the movable contact part making contact with this scraping edge during insertion. A surface of the movable contact part which later establishes the contact thus passes over the scraping edge and possible dirt particles are removed.
[0016] According to an embodiment of the present disclosure, a dirt reservoir is provided adjoining the scraping edge. During a relative movement between the fixed and movable contact parts, the aforementioned dirt particles fall into the dirt reservoir. This may ensure that the dirt particles do not contaminate the contact surface again after scraping.
[0017] According to an embodiment of the present disclosure, a cleaning lip made of a plastic material is attached as the scraping edge. The cleaning lip is attached to an opening of a connector housing surrounding the metal housing. The cleaning lip thus makes contact with a surface of the movable contact part every time the movable contact part is inserted into the metal or connector housing and scrapes off the dirt particle. The dirt particles are then already scraped off the first time they could find their way into the connector housing.
[0018] According to an embodiment of the present disclosure, the cleaning lip is made of a softer material compared to the connector housing. For example, if the connector housing is made of a thermoplastic, then the material of the cleaning lip is either a soft thermoplastic or a hard elastomer. Furthermore, the upper face of the cleaning lip may be chamfered, for example downwardly sloping into the interior of the connector housing. Due to this relatively sharp edge, it is possible, using little friction, to scrape off the majority of the dirt particles and not allow them to penetrate into the housing in the first place. Should dirt particles still find their way into the interior of the connector housing via the cleaning lip, they will slide via the downwardly sloping surface into a first dirt reservoir, which may be disposed between the end face of the fixed contact part and the connector housing. This is thus located beneath the movable contact part and next to the contact surface and will no longer reach the contact surface. The cleaning lip may be disposed perpendicularly to the insertion direction.
[0019] According to an embodiment of the present disclosure, the cleaning lip has an opening that does not impair the scraping edge, but makes the metal housing accessible from outside the connector housing, even in the installed state. This may be advantageous when the metal housing must be unlocked from the connector housing by way of pliers or a screwdriver.
[0020] According to an embodiment of the present disclosure, the metal housing has a latching device on the upper and lower faces, which is used for securing within the connector housing. The metal housing is thus non-slidably disposed in the connector housing, even though forces act on the metal housing as a result of the insertion of the movable contact part in the insertion direction.
[0021] According to an embodiment of the present disclosure, the metal housing is box-shaped and has cut-outs on the lateral walls used to attach the fixed contact part near the lower face of the metal housing. Ultimately, the fixed contact part is fixed in the metal housing in these cut-outs, wherein the fixed contact part comprises catch lugs on the side regions thereof for this purpose.
[0022] According to an embodiment of the present disclosure, so as to generate a pressing force between the contact parts, the metal housing contains a leaf spring in the interior. During insertion of the movable contact part, the leaf spring is slightly tensioned. The pressing force and locking may include an additional locking mechanism, for example, as described in DE 10 1015 104 377. The metal housing comprises a convex region toward the housing interior for this purpose so as to establish the starting and end positions of a movable locking pin. In the end position, the locking pin locks the leaf spring in a pressure position with respect to the contact parts.
[0023] According to an embodiment of the present disclosure, the material can be selected separately for each of the design components. The contact parts are made of copper, for example, and may optionally be coated with silver to further decrease the contact resistance. Independently of the selection of the electrical contact elements, the metal housing may be made of steel to ensure sufficient mechanical strength.
[0024] The described properties of the present disclosure and the manner in which these are achieved will be described in more detail based on the following detailed description. The foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of embodiments consistent with the present disclosure. Further, the accompanying drawings illustrate embodiments of the present disclosure, and together with the description, serve to explain principles of the present disclosure.
BRIEF DESCRIPTION OF THE FIGURES
[0025] FIG. 1 shows an exemplary contact region between a fixed and a movable contact part;
[0026] FIG. 2 shows an exemplary high-current contact comprising a metal housing;
[0027] FIG. 3 shows an exemplary high-current contact comprising a surrounding connector housing made of plastic material;
[0028] FIG. 4 shows a sectional illustration of the high-current contact shown in FIG. 3 ;
[0029] FIG. 5 shows a section of the high-current contact in the region of an opening of the connector housing;
[0030] FIG. 6 shows the high-current contact shown in FIG. 5 , however with a movable contact part that is inserted further;
[0031] FIGS. 7 and 8 show illustrations of an exemplary cleaning lip;
[0032] FIG. 9A shows an exemplary leaf spring, FIG. 9B shows a starting position of the locking pin, and FIG. 9C shows an end position of the locking pin;
[0033] FIG. 10 shows an exemplary movable contact part having a profile;
[0034] FIG. 11 shows a close-up illustration of the profile within the contact surface of the fixed contact part; and
[0035] FIGS. 12 and 13 show further exemplary variants of the profile having a rhombic shape.
DETAILED DESCRIPTION
[0036] FIG. 1 shows how the fixed contact part 2 cooperates with the movable contact part 6 to establish an electrical contact. The two contact parts 2 , 6 are flat stampings, wherein the fixed contact part 2 comprises catch lugs 13 at the side regions 12 thereof, in this example four on each of the two sides. The overlapping region of the two contact parts 2 , 6 is formed by the contact surface 4 . The remaining region of the fixed contact part 2 forms a contact tab 5 , which can be connected to electrical lines or other contact parts corresponding to the respective contacting modules for a weld connection, screw connection or clinch connection.
[0037] In view of the relatively large contact surface 4 , dirt particles between the contact parts 2 , 6 would adversely affect the contact quality. The dirt particles would also be very difficult to remove from the contact surface during operation.
[0038] FIG. 2 shows how the high-current contact establishes a rigid connection between the movable and fixed contact parts 2 , 6 by way of a metal housing 1 . The metal housing 1 is box-shaped and on the side surfaces thereof has cut-outs 10 (four on each of the two sides), which correspond to the catch lugs 13 of the fixed contact part 2 . In this way, the fixed contact part 2 is secured near a bottom surface of the metal housing 1 . This may be achieved, for example, in that the metal housing 1 is initially bent open slightly, so that the fixed contact part 2 can be inserted, and the metal housing 1 is then bent into the final box shape thereof and compressed.
[0039] The metal housing 1 comprises two latching devices 19 , on the top and bottom faces of the metal housing 1 . The metal housing 1 additionally includes a concave portion 11 , which protrudes into the housing interior. A locking pin 17 , which can be displaced along the axis of the high-current contact, is visible in a further elongated hole-shaped opening in the side walls of the metal housing 1 . The pin may reach a starting position 15 and an end position 16 . The locking pin assumes the starting position 15 when the movable contact part is being inserted. Once the movable contact part 6 has been completely inserted, the locking pin 17 is moved into the end position 16 and pushes the leaf spring (which is not visible here and shown in FIGS. 9A-C ) more strongly against the movable contact part 6 , and moreover locks the two contact parts 2 , 6 with respect to each other. In addition to the end points of the elongated hole-shaped opening, the bevels of the concave portion 11 are used to set the two positions 15 , 16 for the locking pin 17 .
[0040] FIG. 3 shows how the metal housing 1 is disposed within a connector housing 9 made of a thermoplastic resin. With the exception of the locking pin 17 , the remaining elements of the metal housing 1 are not illustrated and described again here. The connector housing has an opening 22 into which the movable contact part 6 can be inserted. The opening 22 is slot-shaped to accommodate the movable contact part 6 and moreover has an indentation through which the latching devices 19 shown in FIG. 2 are accessible by way of pliers or a screwdriver.
[0041] FIG. 4 illustrates how the movable contact part 6 penetrates into the connector housing 9 and the metal housing 1 and ultimately reaches the fixed contact part 2 . A scraping edge 8 , which is designed as a cleaning lip, is disposed near the opening 22 of the connector housing 9 . Directly adjoining the cleaning lip 8 is a first dirt reservoir 7 , which is located between the connector housing 9 and the end face of the fixed contact part 2 . Scraped-off dirt particles fall into the dirt reservoir 7 . The cleaning lip 8 is softer than the connector housing 9 and is made of a soft thermoplastic material or a hard elastomer and has a beveled edge on the upper face thereof. In this exemplary embodiment, the beveled edge is downwardly sloping into the housing interior, so that the majority of the dirt remains outside the connector housing 9 during scraping.
[0042] FIGS. 5 and 6 show the process of inserting the movable contact part 6 . FIG. 5 shows the moment at which the movable contact part 6 makes contact with the cleaning lip 8 , when the movable contact part 6 passes through the opening 22 of the connector housing 9 . FIG. 5 illustrates how the latching devices 19 on the upper and lower faces of the metal housing 1 latchingly engage with the connector housing 9 . In addition, the dirt reservoir 7 is also visible. The profile 3 , which will be described in more detail hereafter, comprises further scraping edges and is also indicated on the fixed contact part 2 .
[0043] In FIG. 6 , the movable contact part 6 has been moved further in the insertion direction R and is now in contact with the fixed contact part 2 . At this moment, the movable contact part 6 also passes over the profile 3 and makes contact with the scraping edges located there.
[0044] FIGS. 7 and 8 show cleaning lips 8 from a variety of viewing directions. The scraping edge, which, as described above, is chamfered and downwardly sloping into the housing interior, is located on the upper face 20 of the cleaning lip 8 . Beneath the scraping edge, an opening 21 is provided in the cleaning lip 8 , which, as is apparent from FIG. 5 , is used to access the latching device 19 on the lower face of the metal housing 1 with the aid of pliers or a screwdriver for releasing the latched connection between the metal housing 1 and the connector housing 9 . The two latching devices 19 can be accessed through the opening 21 and through the opening 22 in the connector housing above the movable contact part 6 . The cleaning lip 8 thus does not block the access to this latching device 19 .
[0045] The cleaning lip 8 and the connector housing 9 may be produced as a two-component injection-molded part. Alternatively, the cleaning lip 8 may also be glued or clamped into the connector housing 9 .
[0046] FIG. 9A shows a leaf spring 14 , which is clamped into position by corresponding hooks in the metal housing. The leaf spring 14 made of steel has a hump shape, as a result of which the locking pin 17 (which is not shown in FIG. 9A ) in a starting position 15 (see FIG. 9B ) applies little pressure on the leaf spring 14 , but in an end position 15 (see FIG. 9C ) the leaf spring 14 curves more strongly and is pushed against the movable contact part, thereby creating a pressure position 18 . The operating principle of the leaf spring 14 is described in greater detail in DE 10 2015 104 377.
[0047] The fixed contact part 2 according to FIG. 10 is composed of two parts, these being a contact tab 5 and a profile part that forms the contact surface 4 against the movable contact part (not shown). The catch lugs 13 on the side surfaces of the fixed contact part 2 are also visible here, as is a shoulder between the contact tab 5 and the remainder of the fixed contact part 2 , which implements a stop on the metal housing (not shown).
[0048] The profile 3 generated by way of embossing and stamping on the surface of the fixed contact part 2 has a rhombic shape, comprising a plurality of scraping edges 8 ′ identified by way of example in FIG. 11 , which form an acute angle in relation to the insertion direction R. In this way, dirt particles are cleaned from the surface of the movable contact part by making contact multiple times with the scraping edges 8 ′.
[0049] These dirt particles fall into dirt reservoirs 7 ′ formed between the scraping edges 8 ′. The dirt reservoirs 7 ′ are thus located between the low-profile and high-profile portions of the profile 3 . FIG. 11 also shows that the overall surface area of the low-profile portions is lower than the share of the high-profile portions. The ratio of the low-profile portions to the high-profile portions is approximately 1:5 to 1:10.
[0050] The dimensions of the profile 3 are more clearly apparent from FIGS. 12 and 13 . The profile 3 according to FIG. 12 is located at only one end of the fixed contact part 2 , and may be located at the end that first makes contact with the movable contact part 6 . Since the fixed contact part 2 also has to be inserted into the above-described metal housing 1 , chamfers 31 are provided on the sides of this end, which serve as an insertion aid.
[0051] According to FIG. 13 , the profile 3 extends across a length l of 7.5 mm and across the entire width b of the movable contact part 2 , which is 12 mm. This is intended to illustrate how important it is to cover the entire width of the contact part 2 with the profile 3 , but only a smaller portion of the length of the contact part 2 must be configured with the profile 3 . The profile 3 directly adjoins the end of the fixed contact part 2 . Rhombi 30 form the high-profile portions of the profile 3 . The rhombi 30 have a length lr of 3.5 mm and a width br of 1.7 mm. As a result, a larger number of rhombi 30 , and thus also many scraping edges 8 ′, can be disposed on the relative small surface area of the profile 3 . The scraping edges 8 ′ have a sharp-edged design.
[0052] Gaps 33 , which form the low-profile portions of the profile 3 , and thus also the dirt reservoir 7 ′, are disposed between the rhombi 30 . The gaps 33 are disposed at an angle of 35 ° relative to the insertion direction R. The gaps 33 are rectilinear to ensure good dirt particle transport and have a width bs of 0.5 mm and a depth of 0.8 mm.
[0053] While the present disclosure is illustrated and described in detail according to the above embodiments, the present disclosure is not limited to these embodiments and additional embodiments may be implemented. Further, other embodiments and various modifications will be apparent to those skilled in the art from consideration of the specification and practice of one or more embodiments disclosed herein, without departing from the scope of the present disclosure.
[0000]
List of reference numerals
Metal housing
1
Fixed contact part
2
Profile of the fixed contact part
3
Contact surface
4
Contact tab
5
Movable contact part
6
Dirt reservoir
7, 7′
Scraping edge
8, 8′
Connector housing
9
Cut-outs
10
Concave portion
11
Side regions of the fixed contact part
12
Catch lugs
13
Leaf spring
14
Starting and end positions of the locking pin
15, 16
Locking pin
17
Pressure position of leaf spring
18
Latching device
19
Upper face of the cleaning lip
20
Opening in the cleaning lip
21
Opening of the connector housing
22
Rhombus
30
Chamfers
31
Deburred edge
32
Gap
33
Insertion direction
R
Length of the profile
l
Width of the profile
b
Length of the rhombus
lr
Width of the rhombus
br
Width of the gap
bs
|
Embodiments disclose an electrical contact including a metal housing and a fixed contact part, which is attached to the metal housing and has a contact surface that, during the attachment, is located within the metal housing, and a contact tab located outside the metal housing. The electrical contact includes a movable contact part, which can be inserted into the metal housing to form an electrical contact together with the contact surface of the fixed contact part. A cleaning system is provided in that at least one scraping edge is provided adjoining the contact surface, the movable contact part making contact with said scraping edge during insertion. A surface of the movable contact part passes over the scraping edge to remove possible dirt particles.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims domestic priority on co-pending U.S. Provisional Patent Application Ser. No. 60/969,859, entitled “Baffle Vent with Integral Drift Blocker” and filed on Sep. 4, 2007, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates generally to attic vent baffles commonly used in residential building structures to allow ventilation flow from soffit vents into an attic space for venting from the attic, and, more particularly to a baffle vent with integral drift blocker that can be used in the manufactured housing industry.
BACKGROUND OF THE INVENTION
Attic ventilation systems are typically used in residential buildings to provide proper ventilation of the attic space, which is desired to help prevent formation of condensation along the interior surface of the roof. Condensation can damage the attic insulation and the wooden structure of the building itself. Proper ventilation also helps to prevent premature melting of snow accumulated on a building roof, which can lead to the formation of ice on the roof that presents a safety hazard and can also lead to roof damage. Such attic ventilation systems will utilize vents placed into the underside of the soffit, which projects outwardly from the roof of the building and forms the overhang at the perimeter of the building roof. The intent of these attic ventilation systems is for air to travel through the soffit vents into the attic space and be discharged through an attic vent, which is typically placed at the apex of the roof.
The use of insulation in the attic to provide a barrier to the transmission of heat between the occupied portion of the building structure and the unoccupied attic portion of the building can restrict, or even prevent, the flow of air from the soffits to the roof vent at the apex of the roof. The insulation can be packed along the joists of the roof trusses to the soffits and not allow a passageway for the movement of air past the insulation into the portion of the attic above the insulation. Known construction of the insulation material can include cellulose, rock wool, fiberglass and expanded foam, the latter being used most often in manufactured housing, i.e. housing constructed in a factory and transported to the job site instead of being constructed at the job site. To maintain a discrete passageway for the movement of from the soffit, past the insulation barrier, and into the upper portion of the attic for discharge through the roof vent, baffle vents have been provided for attachment to the interior side of the roof to keep the insulation separated from the interior surface of the roof deck.
One embodiment of a baffle vent can be seen in U.S. Pat. No. 7,094,145, granted on Aug. 22, 2006, to Palle Rye, et al, and assigned to Brentwood Industries, Inc. The Rye baffle vent is stapled to the interior surface of the roof sheeting between the roof rafters and includes a tail portion that is bent in the vicinity of the soffit to extend from the interior surface of the roof sheeting to engage the wall plate. This baffle vent thus forms a barrier that prevents the movement of insulation into the soffit area and restricting the flow of air into the insulation blanket and directs the air flow from the soffit over and above the insulation into the attic. The structure of the baffle vent incorporates a series of convolutions that are oriented parallel to the roof rafters to provide channels that define passageways for the movement of air past the insulation that is engaged against the baffle vent. In operation, the baffle vent utilizes the channels to keep the insulation away from the interior surface of the roof and establishes dedicated passages for the flow of air past the insulation along the interior surface of the roof sheeting.
Earlier configurations of baffle vents can be seen in U.S. Pat. No. 4,446,661, granted to Jan Jonsson, et al, on May 8, 1984, in which a corrugated sheet is fastened to the vertical surfaces of adjacent roof rafters to provide a plurality of longitudinally extending passageways for the movement of air past insulation in the roof. A major consideration in the design and manufacture of such baffle vents is the cost of such structures, particularly when taking into consideration the large square footage of the roofs of some residential buildings. Consequently, baffle vents have been fabricated extensively of foam or plastic material in narrow sheets that form self-supporting structures that can be handled and manipulated into position between the roof rafters for attachment against the interior surface of the roof sheeting. In U.S. Pat. No. 5,341,612, issued to Gary Robbins on Aug. 30, 1994, a baffle vent structure is formed of a thinner foam sheet material and includes a reinforced structure to prevent the vents from collapsing during shipping, handling and installation, as well as to prevent collapsing of the vents from compacted insulation which often is blown into attic areas of a building against the underside of the baffle vents.
Conventional residential construction affected at the job site will typically have the roof structure formed at the same time as the exterior shell of the building so as to get the building under roof to prevent the intrusion of foul weather into the interior of the building. The baffle vents described above are intended for use in such on-site construction techniques. Since the insulation is placed into the attic area long after the roof sheeting and shingles are added to the roof rafters, the baffle vents are formed to be placed between the roof rafters on the underside of the roof sheeting by attaching mounting flanged to either the vertical surfaces of the roof rafters, as is depicted in the aforementioned U.S. Pat. No. 4,446,661 to Jonsson, or the underside of the roof sheeting, as is depicted in U.S. Pat. No. 5,341,612 to Robbins. Generally, the baffle vents are installed as part of the installation of the insulation by contractors that specialize in the installation of insulation, rather than by the roofing contractor that will install the roof vent at the apex of the roof structure.
Manufactured housing is constructed in a factory setting where there is no pressing need to have the roof structure completed before the interior portions of the house are completed. As a result, the baffle vents can be installed on top of the roof rafters before the roof sheeting is fastened to the roof rafters. Generally, manufactured housing is formed with the interior drywall sheeting applied to the bottom side of the ceiling joists to form the inside ceiling of the housing before the roof is completed. The roof sheeting is then attached to the top surfaces of the roof rafters, followed by the application of the exterior roofing materials, typically fiberglass shingles. Insulation can then be installed between the joists on top of the drywall. While blanket fiberglass insulation or blown loose cellulose or fiberglass insulation can be used, expanded foam is often used in manufactured housing construction. The expansion rate of the foam places a substantial pressure on the baffle vent and will often collapse the passageways, resulting in the interruption of the air flow from the soffit past the insulation layer.
An example of a baffle vent that is adapted for use in the manufactured housing setting can be found in U.S. Pat. No. 5,596,847, granted to Michael Stephenson on Jan. 28, 1997. This baffle vent is formed with longitudinally extending ribs that are spaced on eight inch centers so that the single panel can be used on rafters whether spaced sixteen or twenty-four inches apart. A score line is formed on one of the interior ribs so that the excess eight inch strip can be removed if the baffle vent is used on rafters spaced at sixteen inched. In U.S. Pat. No. 4,096,790, issued on Jun. 27, 1978, to Laurence Curran, the baffle vent is formed to span across multiple roof rafters with a panel hanging down to engaged the wall plate and form a barrier to restrict the passage of insulation into the soffit area. In the Curran baffle vent configuration, mounting ribs are spaced at intervals corresponding to the roof rafter structure on which the baffle vent is to be applied. Thus, to be used with sixteen inch and twenty-four inch rafter spacings, the Curran baffle vent would have to be provided in two different models.
The Stephenson baffle vent configuration, and particularly in the Curran baffle vent configuration, the spacing of the longitudinally extending ribs provides a wide span between the ribs to define large passageways for the movement of air along the interior surface of the roof sheeting. Unfortunately, this wide expanse of unreinforced passageway, particularly when the baffle vent is manufactured from foam or a thin plastic material to maintain cost considerations, is subjected to collapse, especially when used with expanding foam insulation techniques. If the passageway collapses, the baffle vent is not functional to allow the passage of air from the soffit past the insulation layer to the upper portions of the attic structure.
Some configurations of manufactured housing are shipped over the highway with the roof structure, which is formed with at least two pivot devices on each side of the roof, collapsed to reduce the height of the transported structure. In such manufactured housing, the pitch of the roof structure is designed so that the attic portion of the building above the first floor can be utilized as an open storage area. Thus, the roof structure from the knee braces toward the center of the roof is open. The insulation is typically placed between the ceiling joists, trapped in the central portion of the building between the drywall panel forming the ceiling of the first floor and the floor decking placed on top of the ceiling joists at the central portion of the building. With the temperature differential between the roof area and the living space in the first floor of the building structure, condensation can accumulate beneath the attic flooring deck, which can eliminate the effectiveness of the insulation, leak into the ceiling of the first floor living space, and/or provide a medium for the growth of mold.
Accordingly, it would be desirable to provide a baffle vent structure that would be particularly adapted for use in the manufactured housing industry to establish and maintain passageways for the movement of air from the building soffit past the insulation layer into the upper attic area for discharge from the attic through a roof vent. It would also be desirable that the baffle vent be formed in a manner to resist a collapsing of the air flow passageways when expanded foam insulation material, or other similar insulation material that exerts a force onto the baffle vent, is installed against the baffle vent. Furthermore, it would be desirable to provide a vent structure that will assist in preventing the accumulation of condensation in the central portion of manufactured housing where the insulation is trapped between ceiling and floor panels on opposite sides of the ceiling joists.
SUMMARY OF THE INVENTION
It is an object of this invention to overcome the disadvantages of the prior art by providing a baffle vent structure that incorporates an integral drift blocker that can be oriented at an angle to the baffle vent structure.
It is another object of this invention to provide a baffle vent structure that is adapted for use in manufactured housing structures.
It is a feature of this invention that the baffle vent is designed to be placed on top of the roof rafters prior to the installation of the roof sheeting member.
It is another feature of this invention that the drift blocker portion of the baffle vent structure is integrally formed with the main body portion of the baffle vent structure by a planar portion that will allow the drift blocker portion to bend relative to the main body portion.
It is an advantage of this invention that the drift blocker portion will fall into a generally vertical orientation when the main body portion of the baffle vent structure is installed on the roof rafters.
It is still another feature of this invention that the main body portion is formed with transversely extending ribs to stiffen the main body portion, while the integral drift blocker portion is formed with longitudinally extending ribs to stiffen the drift blocker portion.
It is another advantage of this invention that the planar transition portion between the main body portion and the drift blocker portion is devoid of stiffening ribs to allow the drift blocker portion to move relative to the main body portion.
It is yet another feature of this invention to provide a baffle vent structure that incorporates a return lip along the longitudinally extending edges of the main body portion to position the main body portion on the top of the roof rafters in a manufactured housing operation before the roof sheeting is applied on top of the baffle vent structure.
It is still another object of this invention to provide a baffle vent structure that can be manufactured in sheet form to span across several roof rafters in a manufactured housing operation.
It is another feature of this invention that the sheet form of the baffle vent structure incorporates multiple drift blocker portions attached to the main body portion of the baffle vent structure.
It is still another advantage of this invention that the drift blocker portions are formed with a gap between the multiple drift blocker portions to accommodate the roof rafters extending between the drift blocker portions beneath the main body portion of the baffle vent structure.
It is yet another advantage of this invention that each of the drift blocker portions is attached to the main body portion of the baffle vent structure by respective planar transition portions.
It is a further advantage of this invention that the drift blocker portions can contain the insulation materials within the manufactured building structure while the manufactured housing is being shipped from the factory to the job site.
It is yet another object of this invention to provide a deck baffle panel on the ceiling joists to provide air movement beneath attic flooring to allow moisture to move toward a roof vent.
It is a further feature of this invention that the deck baffle panel extends past the knee brace interconnecting the ceiling joists and the roof rafters.
It is still a further advantage of this invention that the deck baffle panel will draw an air flow from the baffle vent to extract condensation from beneath the attic flooring.
It is yet another advantage of this invention that the use of the deck baffle panel will allow the removal of moisture that facilitates the growth of mold beneath the attic flooring.
It is yet a further feature of this invention that the deck baffle panel is formed in the same configuration as the main body portion of the baffle vent structure.
It is yet another object of this invention to provide a baffle vent for use in manufactured housing, which is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use.
These and other objects, features and advantages are accomplished according to the instant invention by providing a baffle vent incorporating an integral drift blocker portion that is connected to the main body portion of the baffle vent by a generally planar transition portion to allow the drift blocker portion to move relative to the main body portion. The main body portion is formed with transversely extending stiffening ribs, while the drift blocker portion is formed with longitudinally extending stiffening ribs with the transition portion being devoid of stiffening ribs to maintain flexibility in the transition portion. The baffle vent structure can be formed in large sheets that span several roof rafters with multiple integral drift blocker portions formed to be positioned between the roof rafters. A deck baffle panel is also provided in a configuration similar to the main body portion to be installed beneath attic flooring in manufactured housing to allow an air flow to remove moisture from beneath the attic flooring.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages of this invention will become apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a top plan view of a baffle vent incorporating the principles of the instant invention, the depicted baffle vent being sized to fit between two adjacent roof rafters spaced on 16 inch centers, the integral drift blocker being oriented generally parallel to the convoluted body portion;
FIG. 2 is an end elevational view of the baffle vent depicted in FIG. 1 looking in the plane of the body portion, the drift blocker being oriented in the general configuration corresponding to deployment;
FIG. 3 is a side elevational view of the baffle vent depicted in FIG. 1 ;
FIG. 4 is a top plan view of an alternative embodiment of the baffle vent incorporating the principles of the instant invention, the integral drift blocker being oriented generally parallel to the convoluted body portion;
FIG. 5 is an end elevational view of the baffle vent depicted in FIG. 4 looking in the plane of the body portion, the drift blocker being oriented in the general configuration corresponding to deployment;
FIG. 6 is a side elevational view of the baffle vent depicted in FIG. 4 ;
FIG. 7 is a perspective view of the baffle vent structure shown in FIG. 1 ;
FIG. 8 is an enlarged partial side elevational view of the body portion of the baffle vent;
FIG. 9 is a vertical elevational view of the baffle vent depicted in FIG. 1 deployed between two adjacent roof rafters;
FIG. 10 is a vertical elevational view of the baffle vent depicted in FIG. 4 deployed between two adjacent roof rafters;
FIG. 11 is an enlarged partial vertical elevational view of the baffle vent depicted in FIG. 1 to show a feature that allows the drift blocker to be adjusted to accommodate rafter spacing less than the nominal intended spacing;
FIG. 12 is an enlarged partial vertical elevational view of the baffle vent shown in FIG. 11 , but depicting the bending of the drift blocker to fit between narrowed rafter spacing;
FIG. 13 is a partial top plan view of another alternative embodiment of the baffle vent incorporating the principles of the instant invention, with the baffle vent formed in a sheet that would span several roof rafter spacings, the integral drift blockers being oriented generally parallel to the convoluted body portion;
FIG. 14 is a partial end elevational view of the baffle vent depicted in FIG. 13 looking in the plane of the body portion, the drift blockers being oriented in the general configuration corresponding to deployment;
FIG. 15 is a partial cross-sectional view of a building structure taken through the soffit area and having a high roof pitch and with a baffle vent incorporating the principals of the instant invention installed therein;
FIG. 16 is a partial cross-sectional view of a building structure taken through the soffit area and having a low roof pitch and with a baffle vent incorporating the principals of the instant invention installed therein;
FIG. 17 is a partial cross-sectional view of a manufactured building structure taken through the soffit area and having a high roof pitch, the roof being pivotally collapsed for transport over the highway and having a baffle vent incorporating the principals of the instant invention installed therein, the ceiling joists also having a deck baffle vent positioned at the central portion of the building structure;
FIG. 18 is a partial cross-sectional view of the manufactured building structure shown in FIG. 17 , but having the roof structure restored to the operative configuration;
FIG. 19 is a partial cross-sectional view of the manufactured building structure shown in FIG. 18 , but having the soffit and roof structure completed;
FIG. 20 is a top plan view of the deck baffle vent utilized in the manufactured building structure shown in FIGS. 17-19 ;
FIG. 21 is an end elevational view of the deck baffle vent shown in FIG. 20 ; and
FIG. 22 is a cross-sectional view of the installed deck baffle vent corresponding to lines 22 - 22 in FIG. 19 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1-12 , a baffle vent incorporating the principles of the instant invention can best be seen. The baffle vent 10 is preferably formed from polyvinyl chloride (PVC) film (not shown) having a thickness of about 12 to 16 millimeters through a conventional vacuum molding process in which the film is placed over a mold (not shown) and heated. A vacuum applied to the film draws the PVC film over a mold to cause the PVC film to assume the shape of the mold. The preferred embodiment of this baffle vent 10 would be formed in specific sizes that corresponding to conventional roof rafter spacing. The baffle vent 10 corresponding to 16 inch roof rafter spacing is depicted in FIGS. 1-12 . The baffle vent 10 corresponding to a conventional 24 inch roof rafter spacing would preferably be formed with two more channels that would expand the overall width of the baffle vent 10 .
The baffle vent 10 is formed with a convoluted body portion 20 having a series of parallel, longitudinally extending flat ridges or plateaus 22 preferably separated by a semi-circular valley 25 defining an overall depth of the baffle vent 10 . The ridges 22 are spaced at four inch centers to provide a uniform configuration that will correspond to both 16 and 24 inch rafter spacings. Each valley 25 between the longitudinally extending ridges 22 is preferably formed in a semi-circular configuration to provide strength in cross-section to resist the expansive forces of the insulation materials, such as expanding foam insulation. Thus, each valley 25 has a rounded bottom surface 26 that is spaced vertically approximately one inch from the top surface 23 of the adjacent ridges 22 .
Each valley 25 extends along the circular arc having a preferred radius of approximately seven-eighths of an inch from the center of the rounded bottom surface 26 through an angular deflection of approximately 68.5 degrees in each direction from the center of the bottom surface 22 , measured from the tangent at the center of the rounded bottom surface 26 , whereupon the valley 25 begins a reverse bend along a radius of approximately three-eighths of an inch to join with the horizontal, flat top surface 23 of the ridge 22 on either side of the valley 25 .
The above-described pattern is repeated on four inch intervals measured from the center of the flat top surface 23 of one ridge 22 to the center of the flat top surface 23 of the next adjacent ridge 22 , and consequently from the center of the rounded bottom surface 26 of each valley 25 to the center of the rounded bottom surface 26 of the next adjacent valley 25 . With this particular configuration of ridges 22 and valleys 25 , the baffle vent 10 can also mate with any oddly spaced roof rafter, so long as the spacing from the next adjacent roof rafter is a multiple of four inches. As an example, the end roof rafter on a roof structure is not always placed at the same sixteen or twenty-four inch spacing as the remaining roof rafters, because the overall length of the roof is not divisible by four feet. In such situations, the end rafter will typically have an end spacing of eight, twelve or twenty inches. The baffle vent 10 can easily accommodate such an odd end spacing with a ridge 22 that will mate with the top surface of the end roof rafter.
The configuration of the end elevation of the baffle vent 10 , as is best seen in FIG. 2 , is such that the arched valleys 25 are supported by the adjacent ridges 22 that are pressed against the underside of the roof sheeting and present an arch to resist the forces exerted by the insulation that is pushing the baffle vent 10 against the underside of the roof sheeting. The arched shape provides a strong geometric configuration that is resistant to collapse.
The body portion 20 of the baffle vent 10 is also preferably formed with transversely extending strengthening ribs 29 uniformly spaced longitudinally along the length of the body portion 20 . The configuration of the ribs 29 are best seen in FIGS. 3 and 8 . These strengthening ribs 29 substantially increase the ability of the body portion 20 to maintain its shape irrespective of the loading placed on the body portion. For example, where the body portion 20 extends along the roof rafters above the insulation layer and the insulation is not exerting any pressure on the body portion 20 , the strengthening ribs 29 prevent the baffle vent 20 from sagging between the rafters. Furthermore, the strengthening ribs 29 increase the resistance of the valleys 25 to the pressure exerted by the insulation to keep the valleys from collapsing upwardly against the roof sheeting.
The embodiment of the baffle vent 10 shown in FIGS. 1-3 is formed to provide a side edge 12 along each transverse side of the baffle vent 10 that will be positioned approximately midway across the roof rafter when the roof rafters maintain the intended spacing. Accordingly, the next baffle vent 10 can be positioned with the side edge thereof adjacent the side edge 12 of the adjacent baffle vent 10 to provide all the baffle vents with an approximately ¾ inch mounting area 14 that can be stapled to the roof rafters on which the baffle vent 10 is mounted.
The embodiment of the baffle vent 10 shown in FIGS. 4-6 is formed with a wider mounting area 14 that is intended to cover the entire top surface of the roof rafter on which the baffle vent 10 is mounted. Furthermore, each side edge 12 is formed with a return lip 15 that will serve to “capture” the roof rafter. The adjacent baffle vent 10 will simply be positioned with the mounting area 14 positioned on top of the previously mounted baffle vent 10 with the return lip 15 extending into the adjacent valley 25 . The advantage of forming the baffle vent 10 with a return lip 15 is that the baffle vent 10 can likely be mounted on top of the roof rafters without stapling the baffle vents 10 to the roof rafters. Once the roof sheeting is installed on top of the roof rafters and the baffle vents 10 , the nails fixing the roof sheeting to the roof rafters will permanently secure the baffle vent 10 to the roof rafters. This feature of enabling the baffle vents 10 to be supported on the roof rafters without stapling until the roof sheeting is installed is particularly important in the production of manufactured housing, which is done indoors in a factory setting where wind in not typically a factor during the manufacturing process.
The baffle vent 10 is also formed with an integral drift blocker 30 that is positionable between the roof rafters on which the baffle vent 10 is mounted. The drift blocker 30 is formed from same PVC film that the body portion 20 is manufactured from, and is formed in the same vacuum molding process. The drift blocker 30 is a generally planar member that projects from the body portion 20 between the mounting areas 14 . A transition portion 32 extends from the transversely convoluted body portion 20 to the planar configuration of the drift blocker 30 . The transition portion 32 is preferably smooth, formed without any ribs 29 , to allow the drift blocker 30 to bend about the transition portion 32 . Without the strengthening ribs 29 , the thin film transition portion 32 is quite flexible.
The drift blocker 30 , however, is preferably formed with longitudinally (vertically) extending strengthening ribs 35 to provide resistance to the pressure exerted by the insulation. Transversely extending strengthening ribs, such as the ribs 29 in the body portion 20 , would not be satisfactory as the transverse lines formed by such strengthening ribs would define a fold line, whereas the vertical strengthening ribs 35 in the drift blocker 30 would provide satisfactory results. Preferably, the vertical strengthening ribs 35 would extend along the entire transverse width of the drift blocker 20 . Either embodiment of the body portion 10 would be formed with an integral drift blocker 30 , as can be seen in FIGS. 1-10 .
Referring now to FIGS. 11 and 12 , the drift blocker 30 is preferably formed with a cut or separation line 37 at each transverse edge of the transition portion 32 where the transition portion 32 joins the convoluted body portion 20 . This cut or separation line 37 is only intended to extend approximately 1½ to 2 inches from the edge of the drift blocker 30 . This separation line 37 enables the drift blocker 30 to be folded along the transverse edge thereof when the spacing between the inside vertical faces of the roof rafters on which the baffle vent 10 is mounted is less than the nominal 14½ inches. A representative folding of the drift blocker 30 is depicted in FIG. 12 .
Yet another embodiment of the instant invention can be seen in FIGS. 13 and 14 . Rather than form the individual baffle vent 10 , as depicted in FIGS. 1-6 , a sufficiently wide vacuum forming machine could form the baffle vent 40 in a continuous manner from a continuous roll of PVC film fed into the vacuum machine. Such a continuous baffle vent 40 would have a practical transverse width of about eight feet, which would correspond to four rafter spacings at 24 inches, or five rafter spacings at 16 inches. The practical considerations relate to handling abilities; however, an eight foot width would present an optimum maximum transverse width for use in the manufactured home industry. In this alternative embodiment, the drift blockers 45 project from the convoluted body portion 42 with a spacing therebetween corresponding to the roof rafters on which the continuous baffle vent 40 are to be mounted. With the spacing of the drift blockers 45 being a critical factor, an eight foot wide continuous baffle vent 40 for use with a 16 inch rafter spacing would have five drift blockers 45 , while the 24 inch rafter spacing version would have only four drift blockers 45 .
As best seen in FIGS. 15 and 16 , the typical roof structure 50 is formed with ceiling joists 55 that function as attic floor joists and are oriented horizontally to support a ceiling structure 56 attached to the underside of the joists 55 . The roof rafters 52 are typically connected to the ends of the ceiling joists 55 and project upwardly therefrom at a prescribed angle to meet at an apex, forming with the ceiling joists 55 a conventional triangular configuration. The roof sheeting 53 is then fastened to the top surfaces of the roof rafters 52 to form the roof structure 50 . The ceiling joists 55 and the roof rafters 52 may be supplied as a pre-assembled roof truss assembly having internal braces (not shown), or alternatively may be assembled at the construction site, and spaced at sixteen or twenty-four inch centers.
The roof rafters 52 will extend downwardly past the ceiling joists 35 to form the eaves or soffits 51 , which are formed with vents 51 a to allow air to flow into the soffits 51 from the outside. The roof rafters 52 and the ceiling joists 55 typically rest on the wall plate 59 . After the roof sheeting 53 is attached to the roof rafters 52 , the roofing surface, usually fiberglass shingles 57 , is attached to the upper side of the roof sheeting 53 to complete the construction of the roof structure 50 . One of ordinary skill in the art will recognize that a roof vent (not shown) is usually placed at the apex of the roof 50 to permit the movement of air from the attic.
Insulation 60 in the desired form is placed between and above the ceiling joists 55 to insulate the living area beneath the ceiling joists 55 . The ceiling material 56 will retain the insulation in the attic. Preferably, the insulation 60 extends to the joinder of the roof rafters 52 and the ceiling joists 55 without extending into the soffits 51 . The baffle vent 10 described above is positioned between the insulation 60 and the underside 54 of the roof sheeting 53 , as will be described in greater detail below. Air can then flow from the outside through the vents 51 a in the soffit 51 through the valleys 25 in the baffle vent 10 defining passageways through the insulation 60 barrier along the underside 54 of the roof sheeting 53 into the attic above the insulation 60 . The air can then be discharged through the roof vent (not shown).
For the preferred use in manufactured housing, the baffle vent 10 is placed on top of the roof rafters 52 before the roof sheeting 53 is placed on the rafters 52 . The baffle vent 10 need only extend along the roof sheeting 53 for a length that is greater than the height of the insulation 60 along the roof sheeting 53 . For most insulation 60 configurations, a length of 39 inches is more than sufficient to extend into the attic above the insulation 60 . The baffle vent 10 formed according to the principles of the instant invention does not require fastening to the tops of the roof rafters 32 when being installed, unless the configuration of the roof rafters mandates stapling to retain the baffle vent 10 in place until the roof sheeting 53 is applied. Once the baffle vent 10 has been mounted on top of the roof rafters 52 , the roof sheeting 53 can then be installed on top of the baffle vent 10 and on top of the roof rafters 52 beyond the baffle vent 10 . The fasteners used to attach the roof sheeting 53 to the roof rafters 52 will easily pass through the baffle vent 10 and retain the baffle vent 10 in the desired location.
As can be seen in a comparison of FIGS. 15 and 16 , the baffle vent 10 can be used with a variety of roof structures irrespective of the pitch at which the roof is formed. For high pitched roofs, such as is depicted in FIG. 15 , the vertical distance between the top of the roof rafter 52 and the wall plate 59 is greater than the corresponding vertical distance for a lower pitch roof structure 50 . The longitudinal length of the drift blocker 30 will enable the bottom edge of the drift blocker 30 to be stapled to the wall plate 59 to secure the drift blocker 30 to the roof structure 50 and prevent the intrusion of insulation 60 into the soffit area 51 . The same drift blocker 30 will extend further down the wall plate 59 in the lower pitch roof structures 50 , as is represented in FIG. 16 to enable the drift blocker 30 to be stapled to the wall plate 59 . Preferably, the drift blocker 30 will be stapled along the top edge of the wall plate 59 , which provides some excess length of the drift blocker 30 when used on low pitch roofs 50 ; however, the excess length of the drift blocker 30 can be cut off with a knife if the excess length is not desired.
Some manufactured housing building structures are formed with sufficiently a high roof pitch that transport over the highway is problematic due to the height of the roof structure 50 above the ground and the transport width of the building structure. With such manufactured housing configurations, the roof structure 50 is formed with a first pivotal connection 62 in the roof rafters 52 to enable the soffit area 51 to be flipped onto the roof structure 50 , as is depicted in FIG. 17 . A second pivot connection 63 in the roof rafters enables the upper portion of the roof structure 50 to be lowered toward the ceiling joists 55 . A third pivot connection 64 allows the knee brace 65 to be folded up against the roof rafters 52 for transport over the highway. In this configuration of manufactured housing, the baffle vent 10 can still be utilized, installed as described in detail above.
Restoration of the roof structure 50 is represented in FIGS. 18 and 19 . In FIG. 18 , the soffit 51 is lowered into place, the upper portion of the roof rafters 52 are raised to the proper orientation, and the knee braces 65 are positioned to support the rafters 52 . Pieces of roof sheeting are placed over the pivot area and the pivot areas are then shingled to complete the roof structure 50 . The soffit is completed with the soffit vent 51 a in place.
As is depicted in FIGS. 17-19 , but particularly in FIG. 19 , the central portion of the attic area between the ceiling joists 55 and the roof rafters 52 , and inwardly from the knee brace 65 , is often configured in manufactured housing to be used as an attic storage area. To permit this use of the central portion of the attic area, the top surface of the ceiling joists 55 are capped with a floor 66 that traps the insulation 60 between the ceiling joists 55 and between the floor 66 and the ceiling panel (typically drywall) 56 . The attic floor 66 extends only to the knee brace 65 as there is no need to continue the flooring 66 outwardly of the knee brace 65 . The differential in temperature between the attic area above the floor 66 and the living area of the first floor below the ceiling panel 56 , once the building structure has been erected and people are living therein, tends to create condensation which collects beneath the floor 66 . Once sufficient condensation has been accumulated, the insulation 60 can become wet and moisture can leak through the drywall ceiling panel 56 . Also, the moist environment between the floor 66 and the ceiling 56 is conducive to the growth of mold.
The placement of a deck baffle panel 70 over the ceiling joists 56 before the flooring material 66 is affixed to the ceiling joists 56 will provide a barrier for the passage of condensation from the flooring material 66 into the insulation 60 . Furthermore, the deck baffle panel 70 will establish channels 72 for the passage of air beneath the flooring deck 66 to remove the moisture into the attic area outwardly of the knee brace 65 . The flow of air from the baffle vent 10 on the roof rafters 52 to provide a passageway from the soffit 51 past the insulation 60 into the roof vent (not shown), will draw an air flow from the deck baffle vent 70 to extract the condensation from beneath the floor 66 .
As can be seen in FIGS. 19-22 , the deck baffle vent 70 is formed in the same convoluted configuration described above with respect to the body portion 20 of the baffle vent 10 , with flat ridges 71 separated by semi-circular valleys 72 . The deck baffle vent 70 is preferably formed in continuous sheets that are eight feet wide, although individual baffle vents, as depicted in FIGS. 1 and 4 could also be utilized. Preferably, the deck baffle vent 70 will terminate outwardly of the knee brace 65 to provide a passageway for the movement of air beneath the floor 66 into the attic area outwardly of the knee brace where this air can be mixed with the flow of air flowing from the soffit 51 to the roof vent (not shown) and expelled from the building structure.
While PVC film is the preferred material from which the baffle vent 10 is formed through the thermal molding, vacuum forming manufacturing process, one of ordinary skill in the art will recognize that other materials may be used in the manufacture of the baffle vent 10 . Sheet metals, thermoplastics, and composite materials composed of fibers impregnated with thermoplastic materials can all be used to form the vent baffle 10 . Sheet metals such as galvanized steel, stainless steel, aluminum and copper can be formed into vent baffles for use in the present invention. Thermoplastic materials which can be used in the present invention in addition to PVC film are, for example, polystyrenes, acetyls, nylons, acrylonitrile-butadiene-styrene (ABS), styrene-acrylonitrile (SAN), polyphenylene oxides, polycarbonates, polyether sulfones, polyaryl sulfones, polyethylene, polystyrene, terephthalates, polyetherketones, polypropylenes, polysilicones, polyphenylene sulfides, polyionomers, polyepoxides, polyvinylidene halides, and derivatives and/or mixtures thereof. The particular material used may depend upon the desired end use and the application conditions associated with that use, as is well known in the art.
It will be understood that changes in the details, materials, steps and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention.
|
A baffle vent incorporates an integral drift blocker portion that is connected to the main body portion of the baffle vent by a generally planar transition portion to allow the drift blocker portion to move relative to the main body portion. The main body portion is formed with transversely extending stiffening ribs, while the drift blocker portion is formed with longitudinally extending stiffening ribs with the transition portion being devoid of stiffening ribs to maintain flexibility in the transition portion. The baffle vent structure can be formed in large sheets that span several roof rafters with multiple integral drift blocker portions formed to be positioned between the roof rafters. A deck baffle panel is also provided in a configuration similar to the main body portion to be installed beneath attic flooring in manufactured housing to allow an air flow to remove moisture from beneath the attic flooring.
| 4
|
TECHNICAL FIELD
[0001] The present invention relates to an electronic control device, and relates to a device which performs a control calculation on the basis of a signal input from various sensors mounted in a control target to the electronic control device and completes a control calculation until a defined timing when a calculation result is output.
BACKGROUND ART
[0002] Conventionally, an electronic control device has been used as a device which controls a control target such as an automatic transmission of a vehicle to track a desired target value. In the electronic control device, there has been used a control called a feed-back control in which a state of the control target is input from various sensors mounted in the control target, and a control calculation is performed by a calculation device such as a microcontroller on the basis of a difference with respect to the target value so as to make the state of the control target approach the control target value. In general, a digital control is used as such a control. In the digital control, the control device is configured on an assumption that the operation is performed along a periodic input/output timing (control period). Therefore, there is a need to observe the control period.
[0003] For this reason, it is required that a high-speed control method is applied to the control calculation in order to improve a rapid responsiveness to the target value. As such a high-speed control method, a model prediction control is exemplified. In the model prediction control, the control target is controlled such that a model of the control target is stored as an internal model in the electronic control device, and a future behavior of the control target is predicted using the internal model. It is possible to control the target value with a high tracking property by predicting the future behavior of the control target. On the contrary, there is required a lot of calculation amount, and a longer time taken for the control calculation.
CITATION LIST
Patent Literature
[0004] PTL 1: Publication of U.S. Pat. No. 4,811,495
SUMMARY OF INVENTION
Technical Problem
[0005] When the high-speed control described above is applicable to a hydraulic control of the automatic transmission of a vehicle for example, a gear shift can be made more smoothly and a ride quality can be improved. On the other hand, such an advanced control method requires a long calculation time as described above. Therefore, it is difficult to apply the control scheme without any change particularly to the electronic control device having a short control period.
[0006] As one of schemes used when the control method requiring a long calculation time is applied to the electronic control device having a short control period, there is a method called speculative execution. The speculative execution is a method to make it possible to secure a long calculation time with respect to an actual calculation time by starting the calculation based on prediction of a future state before an actual input is arrived. Since a timing for starting the calculation can be made earlier up to a timing when a restriction of the control period is satisfied by applying the speculative execution to a control system, the advanced control method can be applied to the electronic control device having a restriction on the control period. On the other hand, the speculative execution has a risk that the prediction may fail since the prediction of the future state is assumed. In a case where the speculative execution is applied to the control, there is a risk that the erroneous control due to the prediction failure may be performed. For example, it is difficult to apply the speculative execution without any change to the electronic control device, such as the electronic control device of a vehicle, for which high reliability and safety are required.
[0007] As one of the methods to solve the problem, PTL 1 discloses an example in which the control calculation is performed on all states of a rotation machine (control target) obtainable in the future and a control output is selected on the basis of validity of the calculation result so as to avoid a risk that an inappropriate control is performed on the control target.
[0008] On the other hand, a method of comprehensively calculating all the states of the control target obtainable in the future as described above is effective in a case where the number of states obtained from the control target is small. However, since a general control target has a number of states, hardware resources necessary for the comprehensive calculation of all the states expand. Therefore, it is difficult to apply such a method to the general control device from the viewpoint of the hardware resources.
[0009] In addition, some of the advanced control methods may require to perform a convergence calculation in which the calculation is repeatedly performed until the calculation result is converged for the purpose of optimization for example. In a case where the convergence calculation is performed, a time taken for the calculation becomes unstable. Therefore, even in a case where the speculative execution succeeds, the calculation may be not completed in the control period, and thus there is a need to prepare a separate countermeasure.
[0010] The invention has been made in view of the problems, and an object thereof is to relieve a risk that an electronic control device erroneously performs a control output due to a prediction failure caused when an advanced control using the speculative execution is performed using limited hardware resources, or due to a failure in a control calculation such as incompletion of the control calculation within the control period caused by the convergence calculation, and accordingly to increase reliability when the electronic control device performs the speculative execution.
Solution to Problem
[0011] The above object can be achieved, for example, by a first calculation unit which performs the calculation using a current input from the outside and a second calculation unit which performs the calculation using a prior input that has been input at a point in time prior to the current input.
Advantageous Effects of Invention
[0012] According to the invention, it is possible to perform speculative execution in which a control calculation starts before an actual input value is arrived.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is a functional block diagram illustrating a configuration of an electronic control device 1 and an automatic transmission (control target) 7 according to a first embodiment of the invention.
[0014] FIG. 2 is a timing chart illustrating an operation of the electronic control device 1 according to the first embodiment of the invention, when it pays attention to a specific control output timing.
[0015] FIG. 3 is a timing chart illustrating an actual operation of the electronic control device 1 according to the first embodiment of the invention.
[0016] FIG. 4 is a functional block diagram illustrating an inner configuration of a second calculation unit 32 in the electronic control device 1 according to the first embodiment of the invention.
[0017] FIG. 5 is a functional block diagram illustrating an inner configuration of the automatic transmission 7 according to the first embodiment of the invention.
[0018] FIG. 6 is a graph illustrating an operation when the electronic control device 1 controls a solenoid valve (control target) 7 according to the first embodiment of the invention.
[0019] FIG. 7 is a table showing evaluation bases when an evaluation unit 4 and a selection unit 5 determine the output of the electronic control device 1 according to a second embodiment of the invention.
[0020] FIG. 8 is a functional block diagram illustrating a configuration of the electronic control device 1 and the automatic transmission 7 according to a third embodiment of the invention.
[0021] FIG. 9 is a functional block diagram illustrating one of exemplary configurations of the electronic control device 1 and the automatic transmission 7 according to a fourth embodiment of the invention.
[0022] FIG. 10 is a functional block diagram illustrating one of exemplary configurations of the electronic control device 1 and the automatic transmission 7 according to the fourth embodiment of the invention.
DESCRIPTION OF EMBODIMENTS
First Embodiment
[0023] Hereinafter, an electronic control device according to a first embodiment of the invention will be described using the drawings.
[0024] FIG. 1 is a block diagram illustrating a configuration of a control system which is made of an electronic control device 1 and an automatic transmission (control target) 7 according to this embodiment. The electronic control device 1 illustrated in FIG. 1 receives a target value of a torque output in the automatic transmission (control target) 7 and an output torque value calculated on the basis of a value such as a rotation rate detected by a sensor (not illustrated) mounted in the automatic transmission 7 from a host electronic control device (not illustrated), and determines a voltage value (control output) to a hydraulic solenoid valve 71 in the automatic transmission 7 . Further, while the actual automatic transmission 71 is configured by a plurality of hydraulic solenoid valves, only a portion related to the hydraulic solenoid valve 71 will be described in this embodiment for the sake of simplicity.
[0025] The electronic control device 1 includes an input processing unit 2 which makes the input to the electronic control device 1 processed and output, a first calculation unit 31 and a second calculation unit 32 which perform a control calculation on the basis of the output of the input processing unit 2 , an evaluation unit 4 which outputs an evaluation result on the basis of the output of the input processing unit 2 and an internal state 41 of the second calculation unit 32 , and a selection unit 5 which receives the evaluation result of the evaluation unit 4 and outputs one of the calculation results of the first calculation unit 31 and the second calculation unit 32 as the electronic control device 1 .
[0026] Hereinafter, the control performed by the electronic control device 1 will be described.
[0027] FIG. 2 is a timing chart for describing a procedure of the control calculation necessarily to perform the control output at time Tout using the first calculation unit 31 and the second calculation unit 32 on the basis of the input value until time Tin 1 . The first calculation unit 31 performs the control calculation within one control period using a MAP control in which an output value with respect to the input value is set in advance, on the basis of an input value 21 at time Tin 1 , and outputs the calculation result at time Tout. With this regard, the second calculation unit 32 performs the control calculation using a model prediction control on the basis of a prior input value 22 that has been input before time Tin 2 , and outputs the calculation result at time Tout. The reason why the calculation start time Tin 2 of the second control unit 32 is earlier than the calculation start time Tin 1 of the first calculation unit is that the control calculation is not possible to be completed within one control period due to the characteristics of the above-described model prediction control, so that the calculation start time is set to be early using speculative execution in order to realize the calculation completion in time Tout. The second calculation unit 32 performing such a calculation has a risk that a prediction in the speculative execution fails as described above so as to fail in the control calculation, and a risk that the calculation is not completed in time Tout because of performing the model prediction control necessary for a convergence calculation. In this embodiment, it is assumed that a variation in calculation time of the convergence calculation becomes sufficiently small with respect to the calculation time assigned to the second calculation unit 32 by performing the speculative execution, and the control calculation is completed within the calculation time assigned to the second calculation unit 32 . Only the risk of failure in the control calculation caused by a prediction failure will be considered. Further, the description about that the electronic control device 1 can be used similarly to this embodiment even in a case where the assumption on the convergence calculation is not established will be made in a second embodiment.
[0028] On the above-described condition, the second calculation unit 32 predicts the input value at time Tin 1 , and performs the speculative execution in which the control calculation starts early. In this embodiment, it is assumed that the calculation time assigned to the second calculation unit 32 is configured of two control periods by performing the speculative execution for the sake of simply explanation.
[0029] Since the second calculation unit 32 is set to perform the control calculation in two control periods, the control calculation for performing the control output at time Tout is started at time Tin 2 in one control period further earlier from time Tin 1 . The second calculation unit 32 performs the speculative execution in which the input value 21 at time Tin 1 necessary for performing the control calculation is predicted at time Tin 2 and calculated on the basis of the prior input value 22 that has been input to the electronic control device 1 until time Tin 2 when the calculation starts. Herein, the input value 21 at time Tin 1 is similarly predicted using the prior input value that has been input before two control periods (that is, time Tin 2 and one control period before that time) for the sake of simplicity.
[0030] The evaluation unit 4 makes an evaluation on the calculation result of the second calculation unit 32 which performs the calculation as described above. The content of the evaluation is a success or failure of the speculative execution. The evaluation unit 4 outputs, to the selection 5 , a signal to select the calculation result of the second calculation unit 32 in a case where the second calculation unit 32 succeeds in the speculative execution, and selects the calculation result of the first calculation unit 31 in a case of failing in the speculative execution. The selection unit 5 selects the calculation result of the first calculation unit 31 or the second calculation unit 32 on the basis of the signal, and outputs the signal as a control output 6 of the electronic control device 1 . Further, the success or failure of the speculative execution can be determined on the basis of whether a prediction value 23 , which is stored as the internal state 41 in the second calculation unit 32 and obtained by predicting the input value 21 at time Tin 1 using the input value before time Ts 2 , falls within a certain threshold value with respect to the input value 11 .
[0031] In practice, since performing the control output every control period, the electronic control device 1 compares the calculation results of the first calculation unit 31 and the second calculation unit 32 every control period as illustrated in a timing chart of FIG. 3 , and selects the control output 6 of the electronic control device 1 . Therefore, the electronic control device 1 is required to have one first calculation unit 31 and calculation units in the second calculation unit 32 as many as the calculation times assigned to the second calculation unit. Since the second calculation unit 32 in this embodiment performs the control calculation in two control periods, the second calculation unit 32 includes two calculation units in order for the electronic control device 1 to output the control output 6 every control period, and the two calculation units necessarily perform the control output alternately.
[0032] FIG. 4 is a diagram illustrating an inner configuration of the second calculation unit 32 . The second calculation unit 32 is configured by an input value buffer 321 which stores and outputs two prior input values 22 that have been input to the electronic control device 1 , an input value prediction unit 322 which calculates the prediction value 23 on the basis of the prior input value 22 stored in the input value buffer 321 , two calculation units A 3231 and B 3232 , each of which outputs a result obtained by the control calculation on the basis of the prediction value 23 output from the input value prediction unit 322 , an output utilization determination unit 324 which determines any one of the calculation units A 3231 and B 3232 to perform the outputting in each control period, and makes an output, a selection unit 325 which selects the calculation unit A 3231 or B 3232 which performs the control output on the basis of the output of the output utilization determination unit 324 , and makes an output to the selection unit 5 , and a selection unit 326 which selects the internal states of the calculation units A 3231 and B 3232 which perform the control output on the basis of the output of the output utilization determination unit 324 , and outputs the selected state to the evaluation unit 4 . A future input prediction value 23 for determining the success or failure of the above-described speculative execution is assumed to be stored in the calculation units A 3231 and B 3232 , and to be output to the evaluation unit 4 by the selection unit 326 .
[0033] Further, while the calculation time assigned to the speculative execution is assumed to be two control periods in this embodiment, the same configuration may be applied even in a case where two or more control periods are required. In general, in a case where the calculation time in the second calculation unit 32 becomes N control periods, the number of calculation units mounted in the second calculation unit 32 is “N”, and accordingly the number of inputs of the selection units 324 and 325 changes in accordance therewith. In addition, even the number of prior input values which are stored in the past by the input value buffer 321 storing the prior input value 22 that has been input to the input value prediction unit 322 may arbitrarily change in accordance with the installation of the input value prediction unit 322 .
[0034] The operation of the automatic transmission 7 controlled by the electronic control device 1 which performs the above-described control will be described in the following.
[0035] FIG. 5 illustrates a configuration of the automatic transmission 7 which is a control target in this embodiment. Further, for the sake of simplicity, the automatic transmission 7 is provided with one hydraulic solenoid valve 71 which is driven by the voltage value (control output) of the electronic control device 1 , a hydraulic circuit unit 72 which is controlled by the hydraulic solenoid valve 71 , and a mechanism unit 73 which outputs torque to make an actual gear shift while being controlled by the hydraulic circuit unit 72 .
[0036] FIG. 6 is a graph illustrating a change at the time of gear shift (up shift) of the output torque of the automatic transmission 7 when the solenoid valve in the automatic transmission 7 is controlled by the electronic control device 1 according to the invention. A target value of the output torque is depicted by a solid line, the output torque value in a case where the control is performed using the calculation result of the first calculation unit is depicted by a chain line, and the output torque value in a case where the control is performed using the calculation result of the second calculation unit is depicted by a dotted line. In FIG. 6 , the description will be made about a behavior of the output torque of the automatic transmission 7 when the gear shift starts at time T 0 and is completed at time T 1 , and the gear shift restarts at time T 2 and is stopped by changing an opening of an accelerator at time T 3 .
[0037] While the automatic transmission 7 starts to make a gear shift at time T 0 , the target value of the output torque does not change. Therefore, the speculative execution in the second calculation unit is able to easily succeed. In this case, since the calculation result of the second calculation unit 32 is used as the output of the electronic control device 1 in a period from time T 0 to time T 1 , the output torque shows a behavior depicted by a broken line, and a smooth gear shift can be made in which a shock of the gear shift is less than that in the conventional control. However, when the gear shift is made at the second time after time T 2 , the target value of the output torque is steeply changed at time T 3 , and thus the prediction value 23 in the second calculation unit 32 is differentiated from the actual input value 21 . Therefore, it is not possible to perform the control with a good tracking property since the control is made to follow the target value different from the prediction based on the prior input value 22 as depicted by a broken line together with the actual target value. At this time, the evaluation unit 4 determines that the speculative execution fails, and the selection unit 5 selects the calculation result of the first calculation unit 31 as the control output of the electronic control device 1 . Therefore, it is possible to prevent an operation which is unexpected by a designer or a driver.
[0038] Further, the first calculation unit 31 and the second calculation unit 32 which perform the control calculation in this embodiment are configured by one per each control output timing, but the invention is not limited thereto. In other words, a plurality of calculation units are mounted in the second calculation unit 32 , and the calculation is performed on a plurality of future input prediction values 23 , so that it is possible to improve a success rate of the speculative execution.
[0039] In addition, while the first calculation unit of the MAP control is mounted in this embodiment, the same operational effect described in the embodiment can be achieved even when a PID control is mounted for example.
[0040] In addition, the above embodiment has been described about an example in which the prediction value 23 used in the calculation by the second calculation unit 32 is calculated by the input value prediction unit 322 in the second calculation unit, and used by the calculation unit A 3231 and the calculation unit B 3232 . However, the prediction value 23 may be given to the second calculation unit from a host electronic control device (not illustrated). With such a configuration, the same operational effect as that described in the embodiment can be obtained.
[0041] Further, various modifications described above may be applied alone, or may be applied in combination.
[0042] The above-described embodiment and various modifications are described as merely exemplary, and the invention is not limited to these contents as long as the features of the invention are not spoiled.
Second Embodiment
[0043] Next, an electronic control device according to a second embodiment of the invention will be described using the drawings.
[0044] In this embodiment, the hardware configuration is the same as that of the first embodiment, and the description will be made about that the electronic control device 1 can be increased in reliability by determining the calculation failure of the second calculation unit 32 and using the first calculation unit 31 even in a case where the assumption of the first embodiment is not established in which the variation in calculation time of the convergence calculation performed by the second calculation unit 32 is sufficiently small to be negligible with respect to the calculation time assigned to the second calculation unit 32 .
[0045] Hereinafter, an operation of the electronic control device 1 in this embodiment will be described.
[0046] Since an influence of the convergence calculation is not negligible in this embodiment while the calculation starts before two control periods in the first embodiment described above, there may be a case where the second calculation unit 32 does not complete the calculation until time Tout at which the control output in FIG. 2 is performed. When the convergence calculation is performed, there is a predetermined condition that the calculation is ended, and the calculation is repeatedly performed until the calculation end condition is satisfied. For example, in a case where the calculation is performed in the second calculation unit 32 using an algorithm such as the steepest descent method, the input is updated using a unique recursion formula, and the calculation is ended when a gradient of an evaluation function is less than a reference value. The evaluation unit 4 can determine whether the calculation of the second calculation unit 32 is ended by outputting a flag indicating the calculation end to the evaluation unit 4 .
[0047] The evaluation unit 4 determines the calculation end of the second calculation unit in addition to the determination on the success or failure of the speculative execution in the first embodiment. The evaluation unit 4 sets the calculation result of the second calculation unit 32 as the control output of the electronic control device 1 using the selection unit 5 when the speculative execution succeeds and the convergence calculation is ended as Condition 1 denoted in FIG. 7 , and sets the calculation result of the first calculation unit 31 in other cases.
[0048] The above-described operation of the electronic control device 1 in this embodiment is different from the first embodiment. According to this embodiment, even in a case where the variation in calculation time when the convergence calculation is performed is not negligible while the speculative execution is performed in the second calculation unit 32 described in the first embodiment, it is possible to evaluate validity of the calculation result in the second calculation unit 32 using the evaluation unit 4 . Therefore, it is possible to perform the same control as that of the first embodiment with respect to the automatic transmission (control target) 7 .
Third Embodiment
[0049] Next, an electronic control device according to a third embodiment of the invention will be described using the drawing.
[0050] FIG. 8 is a block diagram illustrating a configuration of a control system which is made of the electronic control device 1 in this embodiment and the automatic transmission (control target) 7 . A difference in the hardware configuration between this embodiment and the first embodiment is that an output correction unit 9 is added which receives the output of the selection unit 5 in the electronic control device 1 and outputs the control output of the electronic control device 1 .
[0051] Hereinafter, an operation of the first calculation unit 31 in this embodiment will be described.
[0052] In a case where the calculation result of the second calculation unit 32 is failure in the first and second embodiments, the calculation result of the first calculation unit 31 is output as the control output of the electronic control device 1 by the selection unit 5 . At this time, since the first calculation unit 31 and the second calculation unit 32 are different in the tracking property with respect to the control goal, the values of the control output of the electronic control device 1 are deviated between the previous calculation result (control output) of the second calculation unit 32 of the electronic control device 1 and the next calculation result of the first calculation unit 31 . Therefore, there is a possibility that the behavior of the automatic transmission (control target) 7 becomes unstable. In order to prevent such an instability, it is considered to add a function of correcting the control output of the electronic control device 1 to the selection unit 5 . In this embodiment, it is desirable that the control target cause a smooth change in the output. Therefore, it is desirable that the outputs of the first calculation unit 31 and the second calculation unit 32 be not instantaneously changed with respect to the control output of the electronic control device 1 . As an example of installation, a filter circuit is configured in the output correction unit 8 to suppress the instantaneous change of the output, so that it is possible to alleviate a risk that the control target 7 becomes unstable due to a steep change of the control output value of the electronic control device 1 .
Fourth Embodiment
[0053] Next, an electronic control device according to a fourth embodiment of the invention will be described using the drawings.
[0054] FIGS. 9 and 10 are block diagrams illustrating a configuration of a control system which is made of the electronic control device 1 in this embodiment and the automatic transmission (control target) 7 . The hardware configuration of this embodiment is different from that of the first embodiment in that the evaluation result of the calculation result of the second calculation unit performed by the evaluation unit 4 is added with the calculation result of the first calculation unit 31 as the input value with respect to the second calculation unit 32 in the electronic control device 1 ( FIG. 9 ), or the control output of the electronic control device 1 is added ( FIG. 10 ). The mounting methods of FIGS. 9 and 10 are different in the hardware configuration, but have the same effect in functionality.
[0055] Hereinafter, an operation of the second calculation unit 32 in this embodiment will be described. First, the operation of the second calculation unit 32 , when the output of the second calculation unit 32 is used as the output of the electronic control device 1 by the evaluation unit 4 and the selection unit 5 (that is in a case where the calculation result of the first calculation unit 31 is not used as the control output of the electronic control device 1 ), is the same as that of the first embodiment.
[0056] With this regard, in a case where the second calculation unit 32 fails in the speculative execution, or the convergence calculation is incomplete, the calculation result of the first calculation unit 31 is used as the control output of the electronic control device 1 by the evaluation unit 4 and the selection unit 5 . At this time, the second calculation unit 32 in the first embodiment uses only the control target value from a host controller (not illustrated) input to the electronic control device 1 and the output of the automatic transmission (control target) 7 to recover the control calculation. At this time, since the automatic transmission 7 is controlled not by the second calculation unit 32 but by the first control unit 31 , the output of the electronic control device 1 is not possible to be obtained from the second calculation unit 32 . Therefore, it is difficult to estimate the internal state of the automatic transmission (control target) 7 . As a result, the internal state of the control target is not possible to be estimated until the state of the control target becomes stable about the control target value, and it is considered that a failing period of the speculative execution is lengthened more than necessary. In this embodiment, when the calculation result of the first calculation unit 31 is output as a result of the evaluation unit 4 , the estimation and the calculation of the internal state of the control target becomes possible in the second calculation unit 32 by confirming the output value of the first calculation unit 31 . Further, it is possible to shorten a time taken until that the second calculation unit 32 is reused in the first embodiment.
REFERENCE SIGNS LIST
[0000]
1 electronic control device
2 input processing unit in electronic control device
21 input value at time Tin 1 to electronic control device
22 plurality of input values at time before time Tin 2 to electronic control device
23 prediction value of input value at time Tin 1 at time Tin 2
31 first calculation unit
32 second calculation unit
321 input value buffer to second control unit
322 input value prediction unit which predicts future input value on the basis of input value buffer
3231 calculation unit A mounted in second calculation unit
3232 calculation unit B mounted in second calculation unit
324 selection unit which selects calculation unit for performing output every control period from among calculation units in second calculation unit
325 selection unit which selects internal state of calculation unit for performing output every control period from among internal states of calculation unit in second calculation unit
326 output utilization determination unit which determines calculation unit for performing output every control period from among internal states of plurality of calculation units in second calculation unit
4 evaluation unit
41 internal state of second calculation unit
5 selection unit
6 correction unit which corrects steep variation in time of output of electronic control device
7 automatic transmission which is control target
71 hydraulic solenoid valve in automatic transmission
72 hydraulic circuit in automatic transmission
73 machinery such as clutch and gear in automatic transmission
|
The objective of the present invention is to increase reliability in an electronic control device when speculative execution is performed, by reducing the risk of erroneous control by the electronic control device, said erroneous control being due to speculative execution failures (such as failures to predict a future state or failure to complete a control calculation due to the execution of an advanced control calculation) which are generated when speculative execution is performed using limited hardware resources in an electronic control device having a control period restriction. Therefore, this electronic control device, which performs a calculation in accordance with one or more external inputs, and outputs a calculation result by a prescribed time, has one or more first calculation units that perform a calculation using a current input, and one or more second calculation units that perform a calculation using a prior input that been input at a point in time prior to the current input.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of application Ser. No. 11/892,418, filed Aug. 22, 2007, the priority of which is hereby claimed.
BACKGROUND OF THE INVENTION
[0002] 1. Field Of The Invention
[0003] The present invention relates to a spark-ignited gas engine with a number of cylinders, wherein on each cylinder a mechanical fuel feed valve for direct feeding of gaseous fuel into the cylinder and a fuel line opening into the cylinder are provided and the fuel line can be closed by the mechanical fuel feed valve in the direction of the cylinder. The invention also relates to a method for controlling such a gas engine and a method for converting a gas engine to such a gas engine.
[0004] 2. The Prior Art
[0005] In spark-ignited gas engines, e.g., large-volume gas engines operated with natural gas in natural gas extraction and transport or in the chemical industry, the gaseous fuel (natural gas, liquefied gas, hydrogen, etc.) is metered at low pressure directly into the cylinders when a mechanical fuel feed valve is opened. When the fuel feed valve is open, gaseous fuel flows through the mechanical fuel feed valve, then through the fuel line and into the cylinder. Because of the low pressure the gas feed takes place at low cylinder pressure, e.g., during the initial compression phase. The fuel feed into the cylinder is discontinued once the fuel feed valve is closed again. The mechanical fuel feed valve is generally controlled by a camshaft and therefore opens for a predetermined crank angle range or a period of time as a function of the speed. On engines that have mechanical fuel injection valves that are operated by a camshaft and push-rods, the valve opens and closes for the same period of time, no matter what the load is, as long as the speed is the same. Since this determines the opening time, the mount of fuel amount fed to the cylinder depends largely on the prevailing pressure in the fuel line. In order to control such a gas engine, for example when the load varies, the pressure in the fuel line must consequently be controlled by a governor. However, such control is expensive and under certain conditions causes irregular combustion and unstable and unreliable operation of the gas engine, which in turn can lead to operational and mechanical problems. Another problem of such mechanical control of a two-stroke gas engine is that unburnt fuel from the cylinder can flow into the intake manifold and/or exhaust pipe when the speed of the gas engine is suddenly reduced, which can lead to dangerous explosions in the intake manifold or exhaust pipe. In addition, mixture is consequently forced back into the gas system, leading to poor metering accuracy and thus misfiring. Hence, when gas engines, especially large-bore gas engines, are run at less than full load, they tend to mis-fire due to the air fuel ratio be too lean for consistent light-off by the spark plug. This is particularly true with pump or blower scavenged engines. These engines have an air pump (or blower) that is driven at engine speed, or a multiple of engine speed, i.e. the amount of air that is pushed through the engine is a function only of the engine speed. These air supplies tend to continue to put a large amount of air in the cylinder (enough for full load). When load is reduced, to maintain a constant speed, the fuel is cut back by the governor to prevent over-speed, which results in an overly lean mixture in the cylinder. Since the air is constant and fuel is reduced, this has a profound effect on the trapped air fuel ratio that the cylinder sees for combustion. This overly lean mixture is hard to ignite, and soon the engine is in lean mis-fire, which causes unburned fuel to be exhausted out the tailpipe of the engine.
[0006] In order to avoid these problems, individually controlled gas valves, e.g., hydraulically and/or electromagnetically controlled valves which inject a predeterminable gas amount into the cylinder during the intake stroke, can be employed instead of the mechanical fuel feed valves. However, in order to be able to feed sufficient fuel into the cylinder despite the very short injection times and the small available opening cross sections, fuel at high pressure is required in these systems, which increases expenditures. Such a gas valve results is disclosed in AT 413 136 B, for example.
[0007] A known method of controlling the speed of a gas engine with individually controlled gas valves operating at loads of less than their rated load is to skip a number of cylinders, e.g. one or more of the number of cylinders, every revolution (or every two revolutions in case of four stroke engine) of the crank shaft by the control system. Every revolution the cylinder(s) skipped is changed. This means that not all cylinders are fuelled but only the number of cylinders required for the current load. In this mode the control system would automatically skip a cylinder because the load did not need all the power the engine was capable of producing, and by sending no fuel to a cylinder which would have mis-fired anyway, the fuel can be saved.
[0008] It is likewise possible in four-stroke engines to feed the gaseous fuel directly into the intake line in which the mixing of air and gaseous fuel then takes place. However, ignitable mixture is then present in the intake manifold, which can lead to undesirable backfiring.
[0009] A spontaneously igniting gas engine is disclosed in JP 08-028 268 A, where through a controlled valve a defined gas amount is introduced into an auxiliary combustion chamber. At the end of the compression phase a mechanical valve is opened so that hot compressed air is able to flow into the auxiliary combustion chamber through which the gas mixture present in the auxiliary combustion chamber is ignited. The ignited gas mixture then expands into the cylinder and brings about the power stroke. However, nothing with regard to metering of gaseous fuel directly into the cylinder of a spark-ignited gas engine may be deduced from JP 08-028 268 A.
[0010] It is an object of the invention to provide a spark-ignited gas engine and a method for controlling such a gas engine which allows accurate, flexible metering of gaseous fuel into the cylinder and hence accurate, flexible control of the gas engine, even at loads of less than their rated load.
SUMMARY OF THE INVENTION
[0011] This object is achieved for the gas engine according to the invention in that a controlled valve is arranged in the fuel line upstream of the fuel feed valve so that in the fuel line between the fuel feed valve and the controlled valve a defined intermediate volume is created and gaseous fuel can be fed via the controlled valve into the intermediate volume. This object is achieved for the method according to the invention in that a controlled valve is arranged in the fuel line upstream of the fuel feed valve so that a defined intermediate volume is created in the fuel line between the fuel feed valve and controlled valve, and in that the amount of fuel fed into the cylinder is set by feeding a defined amount of fuel into the intermediate volume through the controlled valve. With the invention it is possible to admit a defined amount of gaseous fuel into each individual cylinder of the gas engine, thus allowing accurate, flexible control of the gas engine. In addition, the contribution of the individual cylinders to the total output of the gas engine can be easily adjusted. The invention enables gaseous fuel to be fed at a constant pressure to the cylinder for a certain time, independent of crank shaft speed, thus enabling accurate setting of the amount of fuel for each cylinder to achieve uniform combustion and stable operation of the gas engine. This means, furthermore, that a constant rail pressure can be used which eliminates the pressure controlling governor. This greatly stabilizes the response of the system as pressure control does not provide a linear and direct acting control of the injection event. Moreover, no fuel or less fuel can be supplied to one cylinder or a plurality of cylinders by the individual and independent feeding of each cylinder, which, particularly in the partial load range, allows stable operation of the engine which is optimized in terms of fuel economy.
[0012] The inventive fuelling virtually eliminates the possibility for back fire due to sudden loading of the engine as it decouples the fuelling event from the engine rotational velocity. When conventionally fuelled, if the engine suddenly slows down the fuel valve is held open longer since the fuel cam is directly driven by the engine. The increased open time results in a proportionate increase in the delivered fuel and in severe cases this can lead to engine flooding, stalling and backfire. Furthermore, when conventionally fuelled, the governor battles with reducing the fuel pressure to slow the engine down, which holds the valves open longer and so requires further fuel pressure reduction, this places a practical speed limit on the range over which the governor can effectively control the engine. The inventive fuelling allows for fine fuel control at all engine speeds.
[0013] The controlled valve is designed particularly advantageously as a solenoid valve to allow simple, accurate control of the amount of fuel fed.
[0014] Particularly advantageously a certain amount of gaseous fuel is initially pre-stored in the intermediate volume by the controlled valve in that the controlled valve upstream of the fuel feed valve opens and closes before the fuel feed valve opens. When the fuel feed valve opens, a clearly defined amount of fuel (volume of the intermediate volume) is thus fed into the cylinder. Because of this, the influence of the cylinder pressure on the feeding of the fuel into the cylinder is largely eliminated. Moreover, the influence of the control and the size of the mechanical valve are also largely eliminated. In another embodiment of the invention, however, it is also possible to keep the controlled valve open only during the opening time of the fuel feed valve or to open the controlled valve upstream of the fuel feed valve but to close it only during the opening time of the fuel feed valve.
[0015] In order to improve part load operation and fuel economy and to reduce fuel slip it is particularly advantageous feeding no fuel to at least one cylinder for a number of cycles.
[0016] Especially for large engines balancing of the engine is important, which may advantageously be achieved by feeding different amounts of fuel to different cylinders.
[0017] A further object of the invention lies in a simple method of converting an existing gas engine with a mechanically controlled fuel feed valve to a gas engine that can be flexibly, accurately and easily controlled. This object is achieved in that a controlled valve is inserted in the fuel line upstream of the fuel feed valve on the cylinder so that a defined intermediate volume is created between the fuel feed valve and the controlled valve.
[0018] The invention is described in the following by means of the diagrammatic, non-limiting shown in the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 shows a representation of a gas engine according to the invention with a number of cylinders, and
[0020] FIG. 2 shows a detailed view of one of the cylinders of the gas engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] FIG. 1 shows a spark-ignited gas engine 1 , e.g., a large-volume natural gas engine for the compression of natural gas during natural gas transport or of process gases in the chemical industry, which drives a load 3 , e.g., a pump, a compressor, or a generator. The gas engine 1 has, in the known manner, a number of cylinders Z 1 . . . Z n in which a respective piston 13 (see FIG. 2 ) is moved by the combustion of a gaseous fuel. Here, the gas mixture in the cylinder Z is ignited by a spark plug 19 at the end of the compression stroke. Each piston 13 is connected in the known manner by a connecting rod to a crankshaft, not shown here, via which the generated torque is transmitted to the load 3 . Here, the gas engine 1 can be designed as a two or four-stroke engine. The fundamental design of such a spark-ignited gas engine is sufficiently known, and not discussed further here.
[0022] FIG. 2 shows by way of example a cylinder Z of the spark-ignited two-stroke gas engine 1 . The cylinder Z has an inlet port into which an air feed line 17 opens, forcing air into the cylinder Z. An exhaust port which leads into an exhaust pipe 16 is likewise provided on the cylinder Z. In the upper region 18 of the cylinder Z is arranged a mechanical fuel feed valve 11 which is connected to the fuel line 2 and opens into the cylinder Z and via which the fuel can be fed to the cylinder Z. To this end, the fuel feed valve 11 is controlled in the known manner by a camshaft 14 and by pushrods and rocker arms 15 . The opening of the fuel feed valve 11 consequently takes place as a function of the speed of the gas engine 1 and for a given crank angle range. Here, the gaseous fuel is supplied with low pressure at low cylinder pressure, e.g., before the start of the compression phase. To this end, each cylinder Z is connected to a fuel line 2 through which the gaseous fuel is fed to the gas engine 1 .
[0023] In the flow direction of the gaseous fuel upstream of the fuel feed valve 11 a controlled valve 10 , e.g., a solenoid valve, is arranged in the fuel line 2 according to the invention, into which the fuel line 2 opens. Thus, a defined intermediate volume 12 , which is able to accommodate a defined amount of fuel, is created between fuel feed valve 11 and controlled valve 10 . Such an intermediate volume 12 can also obviously be created or enlarged by providing a separate or additional fuel chamber between fuel feed valve 11 and controlled valve 10 . When the fuel feed valve 11 is opened, e.g., at the start of the compression phase, the defined amount of fuel present in the intermediate volume 12 is fed to the cylinder Z.
[0024] Here, the feeding of gaseous fuel into the cylinder Z can be controlled in different ways:
1) Fuel feed valve and controlled valve are open simultaneously
To this end the fuel feed valve 11 opens before the controlled valve 10 , which is again closed before the fuel feed valve 11 . However, for a given pressure the maximum amount of gaseous fuel that can be supplied is determined only by the size and the opening time of the controlled valve.
2) Fuel feed valve and controlled valve are partially open at the same time
The controlled valve 10 in this case opens for a defined period before the fuel feed valve 11 in order to pre-store a defined amount of fuel in the intermediate volume 12 before the fuel feed valve 11 opens. The controlled valve 10 can be closed after or simultaneously with the fuel feed valve 11 . Here, a defined amount of fuel can be stored in the intermediate volume 12 before the fuel feed valve 11 opens.
3) Fuel feed valve and controlled valves open in a staggered manner
The controlled valve 10 opens when the fuel feed valve 11 is closed in order to pre-store a defined amount of fuel in the intermediate volume 12 . Before the fuel feed valve 11 is opened by the cam control, the controlled valve 10 is closed. The two valves thus operate in a staggered manner relative to each other. Thus, a precisely y defined amount of fuel can be fed to the cylinder Z.
[0028] In order to suitably control the controlled valve 10 , a control unit 20 can be provided which has a control input C via which a control objective can be set, e.g., a certain speed, a certain output or a certain torque. The control unit 20 has a separate control output S 1 . . . S n , for each cylinder Z or for each controlled valve 10 , via which the appropriate control signals are transmitted to the controlled valves 10 , e.g., indicating when the valve opens and closes and which opening cross section is exposed (e.g., the stroke in the case of a solenoid valve). To this end the control unit 20 can have additional inputs such as for instance an input for the current speed n or the current torque T, crank angle signal, pressure in the fuel line P G . etc. Appropriate sensors can be arranged on the gas engine 1 for this purpose.
[0029] Although the invention is described above taking the example of a 2-stroke spark-ignited gas engine, the invention is obviously also applicable to 4-stroke engines.
[0030] For a gas engine that is configured as described above, it is very easy to not fuel one or more cylinders (“skip-fire”) if the power from all cylinders is not needed due to the engine having a load less then the rated load. The control system 20 can monitor load (e.g. torque T), and once the load is light enough to warrant disabling a cylinder Z or a number of cylinders Z, the control system 20 can simply not give the signal for a specific controlled valve 10 to open, and no fuel will be delivered to that cylinder Z. Due to the design of the system it is imperative that a certain cylinder Z not be simply skipped for just one cycle, since a single skip would result in an admission of the gas trapped in the intermediate volume for the skipped cycle. This admission would be less than the required amount of fuel required and would result in a very lean mixture. This much leaner mixture would result in poor combustion quality and the fuel from that cycle would be largely wasted. When re-activated, the controlled valve would first have to re-fill the intermediate volume before effectively fuelling the main cylinder, because of this the first fuelled event after a skip would also be very lean and result in poor combustion quality with fuel from that cycle being largely wasted as well. For these reasons, it is important that if the load is such that it would be advantageous to disable a cylinder Z, one or more cylinder(s) Z should be selected, and not be fuelled for some period of time (or number of cycles), but not so long as to allow excessive lubrication to build up in the cylinder and cause a problem. Further, when re-enabling a cylinder it would be advantageous to increase the fuelling event for first fuelled cycle to make up for fuel required in the intermediate volume and ensure good combustion immediately upon re-activation. The length of time (number of cycles) one cylinder can be disabled depends on the gas engine 1 and may be defined and stored in the control system 20 .
[0031] With this system, also more than one cylinder Z can be disabled if the load on the gas engine 1 is light enough. Again, it is imperative that the chosen cylinders Z be disabled for some period of time, and not simply skipped for one revolution.
[0032] Also, the method for determining the number of cylinders Z to disable, and for how long, can all be programmed into the control system 20 . The calculation for determining when a cylinder Z can be disabled without overloading other cylinders Z depends basically on the number of cylinders Z the gas engine 1 has, and on the parasitic load that the gas engine 1 must supply even when there is no output load on the gas engine 1 . These cylinders can be ‘reactivated’ by having the control system 20 begin to open the controlled valve 10 , thus reactivating the cylinder Z. Once the cylinder Z that has been down for a period of time is reactivated, a different cylinder Z can be disabled, thus avoiding the lubrication accumulation that could cause the spark plug 19 to foul, or drainage into the exhaust manifold 16 . This is possible since the spark to the cylinder Z was never shut off, but continued to fire in the presence of air only while the cylinder Z was disabled. The control system 20 should have the ability to determine what the load is on the gas engine 1 , and continually monitor the load in order to prevent over-loading the active cylinders Z. As experiments on existing gas engines showed, the fuel saving for a gas engine 1 operating at less than 85% load can be as high as 10% with this method, and the percentage is even higher when the load is less, and more cylinders Z can be disabled. Moreover, it was found that the improved part load combustion performance is manifested as reductions of emissions related to slipped fuel when this method is applied.
[0033] The inventive fuel control allows for the implementation of optimized power cylinder disablement schemes to improve fuel economy at low load operations for different types of engines. E.g. lean burn engines have an over abundance of air available for combustion. In a proper air fuel ratio scheme, the air is managed as a function of the fuel delivered to the engine. However, there is a lower limit to the air pressure that a turbocharger will supply and in the case of piston scavenged engines, it is not possible to turn the air down. Because of this, there comes a point when the air cannot be decreased for any additional fuel (load) reduction. When this happens, the mixture goes overly lean, combustion stability suffers and the fuel rate of the engine goes up. By implementing a “skip-fire” strategy at just prior to the onset of the lean misfire condition, it is possible to improve the combustion quality of the fired cylinders and to dramatically improve the off load fuel performance of the engine. Skip fire works e.g. by withholding fuel from one or more cylinders and then re-distributing at least part of that fuel to the fired cylinders. This scheme is used to richen the mixture in the fired cylinders so that their combustion performance and efficiency improves and the number of fuelled misfires is greatly reduced or eliminated. The reduction in fuelled misfires results in a reduction in the engine fuel rate.
[0034] The inventive fuel control may also be used for the automatic or continuous balancing of the engine. Balancing of a, especially large, industrial engine is essential to obtaining optimum performance. The large size and relatively slow speed of the engines results in each cylinder operating slightly differently than the other and therefore requires that each cylinder be tuned for its local condition. The inventive fuel control allows for fuelling each cylinder individually and, hence, for balancing the engine. This can be reached e.g. by implementing a feedback system, e.g. a periodic or continuous pressure based feed back or an ion based feed back system, that can be used to maintain the engine balance on a periodic or real time basis. This feedback system ensures that as operating conditions change the unit balance is maintained and the engine is continuously operated at peak efficiency. The balancing control can also be integrated into the control system 20 , which may then have additional inputs required for feedback.
[0035] An existing spark-ignited gas engine 1 with a mechanical fuel feed valve 11 can also be converted with little effort. For this purpose, it is merely required for a controlled valve 10 to be installed on each cylinder Z between the fuel line 2 and the fuel feed valve 11 . To do so, the fuel line 2 is removed, the controlled valve 10 arranged upstream of the fuel feed valve 11 and the fuel line 2 connected to the controlled valve 10 . If required, a separate or additional fuel chamber for creating or enlarging the intermediate volume 12 can be arranged in the flow direction upstream of the cylinder Z to create a larger intermediate volume 12 .
|
Conventional spark-ignited gas engines with a mechanically controlled fuel feed valve have several disadvantages in terms of operation, expensive control, irregular combustion or unstable and unreliable operation, which in turn can lead to operational and mechanical problems. In order to eliminate these disadvantages it is suggested, according to the invention, that a controlled valve is installed in the fuel line upstream of the fuel feed valve so that in the fuel line between fuel feed valve and controlled valve a defined intermediate volume is created and gaseous fuel is fed via the controlled valve into the intermediate volume.
| 5
|
CROSS REFERENCE TO RELATED APPLICATION(S)
This is a divisional of copending application Ser. No. 08/694,964 filed on Aug. 9, 1996.
TECHNICAL FIELD
This invention relates to a wide array thermal ink-jet print head for a printer.
BACKGROUND OF THE INVENTION
Thermal ink-jet printers have become widely popular as inexpensive printing devices. An essential feature of a thermal ink-jet printer is a print head that is controlled to selectively eject tiny droplets of ink onto a printing surface, such as a piece of paper, to form desired images and characters.
The print head generally has an architecture plate with multiple tiny nozzles through which ink droplets are ejected. Adjacent to the nozzles are ink chambers, where ink is stored prior to ejection through the nozzles. Ink is delivered to the ink chambers through ink channels that are in fluid communication with an ink supply.
The print head usually is formed of a sandwich construction, having a substrate at its base. Attached to the substrate is a layer of circuit traces and a layer of the resistors. The resistors are overlaid with a protective, passivation layer. The architecture plate is bonded to the substrate and substantially covers the other layers.
The resistors are lined up beneath the chambers in the architecture plate. Electrical signal inputs to the resistors “fire” the resistors, heating the resistors and thereby a volume of ink within the adjacent ink chamber. The heating generates a vapor bubble in the ink to force an ink droplet out of the nozzle.
Usually, remote bus lines provide signal inputs from an external signal source to the resistors on the print head. Oftentimes, the signals are delivered through multiplexed circuitry on the substrate. The print head is generally connected to these bus lines by a thin flat electrical cable, such as a tape automated bond (“TAB”) circuit. A TAB circuit generally has copper leads supported on a copper-coated tape. The tape is usually bonded onto the print heads with gold bump contacts. Conventional TAB circuit bonding cannot be done over live silicon circuitry without damaging the circuitry and requires use of an encapsulant to protect the leads from the ink, which adds a process step and decreases the robustness of the bond. Nevertheless, TAB circuit bonding is generally used because it is space-efficient, allowing the contact to be made in a tiny area.
In most ink-jet printers, the print head is mounted on an ink pen that is mounted to a carriage that traverses the printing surface to move the print head back and forth over the printing surface. Thus, the print head can be made relatively small in comparison to the width of the printing surface because the ink pen traverses the width of the printing surface. However, it takes the carriage a certain amount of time to traverse the paper, which slows down the speed of printing.
One way to increase the printing speed is to increase the number of nozzles on the print head, which necessitates an increase in the size of the print head. However, increasing the size of the print head requires a larger architecture plate, and a large architecture plate increases the likelihood of failure of the bonding of the interface between the architecture plate and the substrate. One reason for such failure is that the materials for the substrate and the architecture plate usually have considerably different coefficients of thermal expansion. Thus, the sandwich construction may bow or delaminate after assembly as the print head is heated and cooled during operation.
Sometimes, components within ink-jet printers are attached together by flip-chip processing. Flip-chip processing is the term used to describe the method of attaching two parts, such as a die and a substrate, by providing both parts with solderable pads, depositing a solder ball on the solderable pad on the substrate, then placing the solderable pad of the die on top of the solder ball, and heating and pressing the die and substrate to form a solder joint. Often, the solder ball is formed by depositing solder paste on the solderable pad on the substrate and heating the paste and pad to reflow the solder paste into a solder ball.
Oftentimes, after the two parts are attached by flip chip processing, an underfill made of liquid epoxy will be shot between the parts and allowed to wick therebetween, in a process separate from flip-chip processing. The underfill layer comprising the cured epoxy fills gaps between the parts and relieves some of the stress on the solder joint.
Page wide array printheads have been disclosed in U.S. Pat. No. 6,135,586, filed on behalf of Paul H. McClelland et al. on Oct. 31, 1995, titled “Large Area InkJet Printhead” and U.S. Pat. No. 6,017,117, filed on behalf of Paul H. McClelland et al. on Oct. 31, 1995, titled “Printhead With Pump Driven Ink Circulation”. These applications are assigned to the assignee of the present invention.
SUMMARY OF THE INVENTION
The invention generally includes a method of manufacturing a fluid ejection device by providing a substrate; attaching a plurality of resistors to a portion of the substrate for heating fluid; attaching a plurality of solderable interconnect pads to another portion of the substrate; soldering at least one chip onto the interconnect pads; and electrically connecting the resistors with the chip by attaching a layer having circuit traces that run from the interconnect pads to the resistors, whereby the chip is operable to control the resistors.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial top schematic view of the print head of the present invention.
FIG. 2 is a partial top view of the print head of the present invention, with the driver chip removed.
FIG. 3 is a sectional view of an interconnect area of the present invention, taken along line 3 — 3 of FIG. 2 .
FIG. 4 is a sectional view taken along line 4 — 4 of FIG. 2 of the present invention, showing the process of applying solder paste.
FIG. 5 is a sectional view, like FIG. 4, after reflowing the solder paste and removing any flux residues.
FIG. 6 is a sectional view, like FIG. 4, but including the driver chip.
FIG. 7 is a sectional view, like FIG. 4, showing the driver chip bonded to the interconnect area at the print head.
FIG. 8 is a sectional view, like FIG. 4, but showing the use of a removable stencil.
FIG. 9 is a sectional view, like FIG. 8, but with the stencil removed.
FIG. 10 is a partial side view of an ink ejection area of the print head of FIG. 2 .
FIG. 11 is a partial side view, like FIG. 10 . but of an alternative embodiment of the present invention in which an underfill layer defines ink chambers.
FIG. 12 is a partial side view, like FIG. 10 . but of an alternative embodiment of the present invention having an edge-firing architecture plate.
FIG. 13 is a partial sectional view, similar to FIG. 10, but taken through an alternative embodiment of the present invention having a face-firing architecture plate.
FIG. 14 is a sectional view of the architecture plate, taken along line 14 — 14 of FIG. 2 .
FIG. 15 is a partial side view of the face-firing architecture plate of FIG. 13 being cast on a mandrel.
FIG. 16 is a partial side view of the architecture plate detaching from the mandrel of FIG. 13 .
FIG. 17 is a partial side view of the architecture plate of FIG. 13 after chem-lapping.
DETAILED DESCRIPTION OF THE INVENTION
A print head 20 in accordance with the present invention is illustrated in FIG. 2 . The print head 20 is mounted on a printer (not shown) and selectively ejects ink droplets onto a printing surface (not shown), such as a piece of paper, which is advanced through the printer.
As shown in FIGS. 1 and 2, the print head 20 of the present invention has two main areas: an ink-ejection area 22 , from which ink is ejected, or “fired”, onto paper adjacent the ink-ejection area 22 , and an interconnect area 24 that includes a driver chip 26 , or multiple driver chips, for sending signals to the ink-ejection area 22 to eject the ink from the ink-ejection area 22 , as will be described in more detail below.
The ink-ejection area 22 has an architecture plate 30 having chambers 32 for containing small amounts of ink, as best shown in FIG. 10 . Beneath the chambers 32 are resistors 34 that are heated upon receiving a signal from the driver chip 26 . The heat from the resistor heats the ink in the adjacent chamber 32 , which expands the ink, forcing the ink from the chamber 32 onto the paper.
Both the ink-ejection area 22 and the interconnect area 24 are fabricated on a common substrate 36 , as shown in FIG. 2 . The illustrated substrate 36 is an elongated, rectangular block of amorphous silicon with a thickness of 25-50 micrometers (about 1-2 mils). Silicon is particularly well-suited because it is flexible out-of-the-plane and yet is very stiff in the plane, as well as being chemically unreactive at temperatures near room temperature. The stiffness in the plane allows good registration with the architecture plate 30 , which is particularly important when the substrate 36 and plate 30 are several inches long. Nevertheless, the substrate 36 could be made of other materials, such as glass, ceramic, or a metal substrate with a ceramic coating.
As partially indicated in FIG. 3, a circuit trace layer, comprising a plurality of discrete, conductive circuit traces 40 , extends across substrate 36 . The circuit traces 40 connect the ink ejection area 22 with the interconnect area 24 to deliver signals from the driver chip 26 to the resistors 34 , as described in more detail below. The circuit traces 40 are deposited on the substrate 36 by sputtering or, alternatively, by evaporation. The traces 40 preferably are made of tantalum-aluminum/aluminum, approximately 0.6 micrometers thick.
A passivation layer 46 , shown in FIG. 3, is deposited over the traces 40 . The passivation layer 46 preferably is made of nitride/carbide and is 0.25 micrometers (approximately 0.01 mils) thick.
In the interconnect area 24 , vias 50 are created through the passivation layer 46 , such as by etching, to expose portions of the circuit traces 40 to provide an electrical path between the traces 40 and interconnect pads 52 that are sputtered onto the vias 50 and passivation layer 46 . The interconnect pads 52 are deposited by sputter-coating, electroless plating, or a comparable process. The interconnect pads 52 should be solderable. In other words, the interconnect pads 52 should be able to be wetted by solder. The interconnect pads 52 preferably are made of nickel-vanadium/gold and in the illustrated embodiment are disk-shaped with a diameter of 125 micrometers (approximately 5 mils) and a thickness of approximately 1500 angstroms.
As shown in FIG. 2, the interconnect pads 52 are arranged in parallel rows, extending longitudinally along the portion of the substrate 36 shown. Each interconnect pad 52 is connected to a single resistor 34 , except a ground interconnect pad 54 in each row is reserved for ground, as shown in FIG. 3 . Preferably, the pad 54 closest to the resistors 34 is the pad for the common line of a set of resistors 34 , as illustrated in FIG. 2, so as to decrease the line resistance for the line that will carry the most current between the chip 26 and the resistor 34 . The illustrated embodiment shows a print head 20 with a resolution of 600 dots per inch having eight interconnect pads 52 per row on a 250 micrometer pitch, meaning that the centers of the illustrated pads are spaced apart 250 micrometers.
The driver chip 26 , which sends firing signals to the resistors, is attached to the interconnect pads 52 by a combination soldering and polymer bonding technique of the present invention. The technique involves spinning on a thin underfill layer 60 , of approximately 25-125 micrometers (about 1-5 mils) thick, over the circuit traces and interconnect pads 52 (FIG. 3 ). The underfill layer 60 could also be deposited by thick-film lamination. Preferably the underfill layer 60 is made of a photoimageable polyimide.
Openings 62 , preferably circular, are created in the underfill layer 60 to expose the pads 52 and to define a cavity 64 around each pad, as shown in FIG. 3 . The openings 62 could be created by patterning the layer by photoimaging and developing or by chemical etching. The openings 62 could also be created by laser drilling, for example.
Solder paste 66 is deposited in the cavities 64 , as shown in FIG. 4 . The solder paste 66 is reflowed to form a dome-shaped solder ball 68 on top of each interconnect pad 52 , as illustrated in FIG. 5 . The solder paste 66 is approximately 50% solder alloy (containing, for example, tin, lead, bismuth, silver, or indium) and 50% flux by volume.
Preferably, the cavity 64 volume is appropriate for the amount of solder paste 66 necessary to create a solder ball 68 of a sufficient size to attach to a solder pad on one of the driver chips 26 as explained below. In this way, the underfill layer 60 , which defines the cavity volume, acts as an in situ stencil to measure and contain the solder paste 66 , allowing the appropriate amounts of solder paste 66 to be applied quickly. Preferably, the solder paste 66 is applied in and around the openings 62 , and a squeegee 72 is pushed across the surface 74 of the underfill layer 60 to torce the paste 66 into the cavities 64 , to remove any excess solder paste 66 from the surface 74 of the underfill layer 60 , and to level off the solder paste 66 in the cavities 64 , as indicated in FIG. 4 .
If a volume of solder paste 66 larger than the volume of the cavity 64 in the underfill layer 60 is needed, a removable, auxiliary stencil 76 could be placed on top of the underfill layer 60 to create second layer openings 78 to enlarge the volume of the cavity (FIG. 8 ). Solder paste 66 could be deposited while the stencil 76 is in place. The stencil could then be removed before or after the solder ball is formed. The former is indicated in FIG. 9 .
To reflow the solder paste 66 , the paste 66 is heated, preferably to 220 degrees celsius in an inert environment, such as nitrogen. Other inert environments, such as argon and helium, could also be used. The flux residues may be removed, such as by washing away, before assembling the driver chip 26 on the substrate 36 to provide better adhesion of the underfill layer 60 to the driver chip 26 . Eliminating the flux residues is beneficial because the flux residues promote corrosion in high-humidity environments.
A volatile flux could be applied to the solder ball 68 or the interconnect pad 52 on the substrate 36 to promote solder wetting to the interconnect pad 52 on the substrate 36 . The flux is useful when the surface of the solder ball 68 is too oxidized to permit fluxless soldering.
Alternatively, if flux is not used, the surface oxide film that will probably form on the surface of the solder ball 68 could be cracked, as will be described in greater detail below.
The driver chip 26 is provided with solderable pads 86 (FIG. 6 ), similar to the interconnect pads 52 on the substrate 36 . The pads 86 are spaced to correspond with the spacing of the interconnect pads 52 . The driver chip 26 is placed on the solder balls 68 with the solderable pads 86 contacting the tops of the solder balls 68 .
If flux is not used, the surface oxide film on the solder ball 68 may be cracked by pressing the solderable pads 86 on the driver chip 26 against the solder ball 68 , which will allow the liquid solder to wet the solderable pads 86 .
The assembly of the interconnect pads 52 , the solder balls 68 , and the driver chip 26 with the solderable pads 86 is heated to melt the solder and is pressed together. The heat and pressure collapse the solder balls 68 and bond the underfill layer 60 to the driver chip 26 , as shown in FIG. 7 . Heating to a temperature of 220 degrees celsius in nitrogen is effective to melt the solder.
Preferably, the pressure is applied to the assembly in a manner that permits some minute, lateral shifting of the driver chip relative to the substrate so that the surface tension forces on the liquid solder balls 68 and solderable pads 86 tend to pull the driver chip 26 into lateral alignment with the substrate 36 . Alternatively, the parts 26 , 36 could be manually aligned.
After the chip 26 is pressed with heat to collapse the solder balls 68 , solder joints 90 (FIG. 7) or metallic connections between the driver chip 26 and the substrate 36 are formed, and the underfill layer 60 is polymerically bonded to the driver chip 26 , forming a sandwich construction.
Alternatively, the underfill layer 60 could be bonded after the solderjoints 90 are formed. In such a case, the underfill layer 60 would be heated again after the solder joints 90 are formed, and the driver chip 26 would be pressed against the underfill layer 60 to effect the bonding.
The process of the present invention provides a fairly inexpensive way to electrically connect parts, and the configuration of this invention, in particular the rows of interconnect pads 52 extending perpendicularly from the row of resistors 34 , allows the interconnect pads 52 to be spaced apart further than past configurations, which allows this inexpensive connection method to be used.
The process of the present invention could also be used to attach various other microelectronic parts together, such as flexible circuits or wafers of integrated circuits.
The underfill layer 60 functions both as an in situ stencil and as a pre-placed underfill, which supports the driver chip on the substrate to relieve stress from the solder joint between the interconnect pad and the driver chip to thereby increase the fatigue life of the solderjoint. A pre-placed underfill expedites the attachment of the driver chip 26 to the interconnect pads 52 by reducing the number of fabrication steps required and because the underfill layer 60 does not require a long curing time, as does liquid epoxy. The underfill layer 60 is also advantageous because it obstructs moisture and chemicals from entering between the parts, which inhibits corrosion.
Although this description discussed applying the underfill layer to and forming solder balls 68 on the substrate 36 , the underfill layer 60 and solder balls 68 could be deposited on the driver chip 26 instead.
The ink-ejection area 22 on the substrate 36 has a layer of resistors 34 extending across the top of the substrate 36 , near a side 100 of the substrate 36 , as shown in FIG. 2 . The resistors 34 are made from tantalum aluminum, having a thickness of about 950 angstroms, and are sputtered on top of the substrate 36 , as is common in ink-jet technology. As best seen in FIG. 1, the resistors 34 are electrically connected to the driver chip 26 by the circuit traces 40 . The illustrated resistors 34 are square and are sized between about 3 microns by 3 microns and 75 microns by 75 microns, although other shapes and sizes could be used.
The resistors 34 are grouped in sets 102 of, for example, seven resistors, with each set corresponding to a row of interconnect pads 52 . Each row of interconnect pads 52 extends generally perpendicularly from each set of resistors 102 . The illustrated print head 20 has a resolution of 600 dots per inch and has approximately 680 sets of seven resistors each, spaced so that the overall length of the resistor sets is sufficient to cover the printing area on a standard piece of paper. The 680 sets of resistors are driven by the driver chip 26 , or possibly multiple driver chips, through 680 rows of eight interconnect pads 52 . It is envisioned that the resistors 34 could extend to sixty inches to accommodate larger widths of paper.
A cavitation barrier (not shown), preferably of nitride and carbide and a passivation layer (not shown), preferably of tantalum, is deposited over the resistors. Such barriers are commonly used in ink-jet technology to shield the resistors 34 from the ink in the chambers 32 , which is highly corrosive, and from cavitation erosion. Other types of barriers could also be used.
FIG. 10 shows an edge-firing architecture plate 104 positioned over the resistors 34 so that each resistor 34 is centered within one of the chambers 32 in the architecture plate 104 . The edge-firing architecture plate 104 is an elongate, flat, solid, rectangular piece and has small cut-outs 108 in the longitudinal edge 106 of the plate 104 , which form the ink chambers 32 , in which ink is stored until a resistor 34 is heated to eject the ink from the chamber 32 . The cut-outs 108 are longitudinally aligned in sets having the same spacing as the resistors 34 . Partitions 110 are left between the chambers 32 to segregate the ink in adjacent chambers 32 . The ink chambers 32 are fluidically connected with ink channels (not shown), through which ink is delivered from an ink supply (not shown) to the ink chambers.
The illustrated plate 104 also has rectangularly shaped solder wells 112 to provide an area in which to attach the plate 104 to the substrate 36 , as will be explained in greater detail below. The solder wells 112 (one of which is shown in FIG. 10) are positioned at the ends 105 of the plate 104 , and several additional solder wells 113 are positioned laterally adjacent the chambers 32 toward the interconnect area 24 . One well 113 is shown in FIG. 14 .
The architecture plate 104 is preferably made from a material with a coefficient of thermal expansion similar to that of the substrate 36 . Etched or molded glass or amorphous silicon are particularly suitable. Ceramic is also a possibility. Amorphous silicon is preferable if the substrate is also made of amorphous silicon. A glass plate on a glass substrate would also work well. Similar coefficients of thermal expansion will help the plate and substrate maintain alignment over a wide range of temperatures, will not stress the joints unreasonably, and will not tend to warp the assembly. Silicon is especially desirable because it will be somewhat flexible and therefore more resistant to handling damage than a comparable glass part.
The architecture plate 104 is attached to the substrate 36 using the soldering technique described above, which has the added advantage of aligning the architecture plate 104 with the substrate 36 . Specifically, the technique comprises: depositing solderable pads 116 , 117 on the bottom surface 118 of each of the solder wells 112 in the architecture plate 104 and on the circuit traces 40 on the substrate 36 at corresponding locations; depositing solder paste around each of the solderable pads 117 on the circuit trace layer 40 ; heating the solder paste to form a solder ball 166 (shown in dashed lines, FIG. 10) on each of the solderable pads 117 on the circuit trace layer 40 ; positioning the plate 104 adjacent the substrate 36 so that the solderable pads 116 on the plate 104 are aligned with the solder balls 166 on the substrate 36 ; and heating the solderable pads 116 on the plate 104 and the solder balls 166 on the substrate 36 to join (as shown at 168 ) the plate 104 and substrate 36 . The heating is preferably done while at least one of the substrate 36 and plate 104 are unconstrained so that the plate 104 and substrate 36 may self-align. The solder balls 166 should be of a sufficient size to ensure that the plate 104 does not drag on the substrate 36 and prevent alignment. It should be understood that the solder balls 166 could be formed on the solderable pads 116 on the plate 104 instead of the substrate 36 .
After joining the plate 104 and substrate 36 , preferably heat and pressure are applied to the plate 104 and substrate 36 to close any gaps that may exist between the chambers 32 in the plate 104 so that no crosstalk occurs through this path.
It should be evident that the illustrated solder joints formed within the solder wells 112 , 113 only serve to mechanically align the architecture plate 104 and the substrate 36 ; no electrical connections are made.
This invention would also be suitable for other configurations of architecture plates. FIG. 11 shows an alternative edge-firing architecture plate 180 in which the architecture plate 180 is a solid, dielectric block 181 (without cut-outs) and the ink chambers 182 are defined by depositing, preferably by spinning on, a dielectric layer 184 , such as polyimide, over the resistors 34 . The openings for the chambers 182 are created by photoimaging, chemical etching, laser drilling, or the like.
FIG. 12 shows an alternative edge-firing architecture plate 200 having chambers 232 cut into the bottom surface 233 of the architecture plate 200 . Unlike the previously mentioned edge-firing plate 104 , the chambers 232 in the alternatively configured plate 200 do not extend all the way to the longitudinal edge 206 of the plate. Rather, the alternatively configured plate has a nozzle 238 extending from approximately the center of an interior wall (not shown) nearest the edge 200 of each chamber 232 to the longitudinal edge 206 of the plate 200 . For optimal ink flow and directional stability of the ejected ink, the nozzle 238 should taper from the interior wall of the chamber 232 to the edge 206 of the plate.
FIG. 13 shows yet another alternative architecture plate, designated a face-firing plate 300 . The face-firing plate 300 has frustrum-shaped ink chambers 332 extending from the bottom surface 333 of the plate 300 approximately two-thirds of the way through the plate 300 . The chambers 332 are aligned longitudinally along the plate 300 and are spaced in sets to correspond with the spacing of the sets of resistors 34 on the substrate 36 . Frustum-shaped nozzles 342 extend from the chambers 332 to the top surface 343 of the plate 300 . Ink is fired by the resistors 34 from the chambers 332 , through the nozzles 342 , and onto paper being fed along the top surface 343 of the architecture plate 300 .
Alternatively, ink chambers for the alternative plates 200 , 300 could be defined using a dielectric layer, as described in conjunction with plate 180 .
FIG. 15 illustrates the fabrication of the face-firing architecture plate 300 on a mandrel 120 . Any of the illustrated architecture plates 104 , 200 , 300 may be fabricated using a mandrel. The mandrel 120 has the negative of the features of the desired architecture plate and is preferably made of alumina or another material having a higher enthalpy of formation than the material of the architecture plate (silicon dioxide, for instance), so the mandrel is not affected chemically during fabrication, and a higher coefficient of thermal expansion than the material of the architecture plate. Thus, as long as the mandrel 120 is designed with the proper draft angles the plate 300 will “pop off the mandrel during cooling, as indicated in FIG. 16 . The architecture plate is then “chem-lapped” to the desired flatness and thickness and to create the nozzles 342 , as shown in FIG. 17 . Chem-lapping involves subjecting the plate to chemical mechanical planarization, in which the plate is abraded by a combination of mechanical disturbance and etching chemicals.
An encapsulant (not shown), such as polyimide, could be applied to the periphery of the joint (not shown) between the plates 104 , 200 , 300 and the substrate 36 to prevent ink leakage therefrom.
The solder balls for attaching any of the architecture plates 104 , 200 , 300 to the substrate 36 could be formed at the same time the solder balls 68 for attaching the driver chip 26 to the substrate 36 are formed.
This description illustrates various embodiments of the present invention and should not be construed to limit the scope thereof in any way. Other modifications and variations may be made to the method and assembly described without departing from the invention as defined by the appended claims and their equivalents.
|
A method of manufacturing a fluid ejection device includes attaching a plurality of resistors to a portion of the substrate for heating fluid; attaching a plurality of solderable interconnect pads to another portion of the substrate; soldering at least one chip onto the interconnect pads; and electrically connecting the resistors with the chip by attaching a layer having circuit traces that run from the interconnect pads to the resistors, whereby the chip is operable to control the resistors.
| 1
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 14/252,910 filed on Apr. 15, 2014, the entire contents of which are incorporated by reference herein.
TECHNICAL FIELD
[0002] The application relates generally to methods of determining radii of tools, and more specifically of tools for turning machines.
BACKGROUND OF THE ART
[0003] Turning machines, such as in-turn, mill-turn, and lathes, CNC use tools to carve channels or sections in a rotating part. The tools include a cutting end which, as sharp as it may be, has a rounded portion at its tip. The positioning of the cutting end of the tool determines a position of the channel or section to be removed. In some application, the position of the tool may be required with greater precision before the tool is used. In order to determine the position of the tool, probes, for example mechanical or optical, may be used.
[0004] Touch probes typically contact the tool at various locations to determine a position of the tool's cutting end in a plane. A radius of the cutting end's rounded portion is based on nominal values given by the manufacturer of the tool. The nominal values may not correspond enough to the actual radius of the cutting end which could lead to imprecise cutting.
[0005] Optical sensors such as laser beam detectors can be used to scan the cutting end of the tool in order to determine its radius. The optical methods are however calculation intensive, and can be sensitive to noise coming from chips of material or thin layers of fluids.
SUMMARY
[0006] In one aspect, there is provided a method of determining a radius of a cutting end of a tool for a turning machine using a touch probe, one of the cutting end and the touch probe being movable relative to a reference frame having a first axis and a second axis, the one of the one of the cutting end and the touch probe having a reference point trackable in the reference frame, the method comprising: a) establishing a first contact point between the touch probe and the cutting end and recording a first coordinate of the reference point on the first axis, the first contact point having a known coordinate on the first axis; and b) establishing a second contact point between the touch probe and the cutting end and recording a second coordinate of the reference point on the second axis, the second contact point having a known coordinate on the second axis; and c) establishing a third contact point between the touch probe and the cutting end by moving an end point of the one of the cutting end and the touch probe along a predetermined direction at an angle with the first and second axes and recording a third coordinate of the reference point on the first axis and a fourth coordinate of the reference point on the second axis upon contact, the pre-determined direction being dependent on the coordinate of the first contact point on the first axis and the coordinate of the second contact point on the second axis, the end point being offset from the reference point by an amount deduced from the first coordinate and the second coordinate recorded at steps a) and b); and d) determining a radius of the cutting end based on the first, second, third and fourth coordinates.
[0007] In another aspect, there is provided a method of determining a radius of a cutting end of a tool for a turning machine using a touch probe, one of the cutting end and the touch probe being movable relative to a reference frame having a first axis and a second axis, the one of the one of the cutting end and the touch probe having a reference point trackable in the reference frame, the method comprising: a) recording a first coordinate of the reference point on the first axis upon contacting the touch probe and the cutting end at a first contact point having a known coordinate on the first axis; b) calculating a first offset of an end point of the one of the cutting end and the touch probe relative to the reference point on the first axis based on the first coordinate; c) recording a second coordinate of the reference point on the second axis upon contacting the touch probe and the cutting end at a second contact point having a known coordinate on the second axis; and d) calculating a second offset of the end point relative to the reference point on the second axis based on the second coordinate; e) recording a third coordinate of the reference point on the first axis and a fourth coordinate of the reference point on the second axis upon moving an end point of the one of the cutting end and the touch probe along a predetermined direction and contacting the touch probe and the cutting end at a third contact point along the predetermined direction, the third contact point having known coordinates on the first and second axes, the predetermined direction being at an angle with the first and second axes and being determined from the coordinate of the first contact point on the first axis and the coordinate of the second contact point on the second axis, the end point calculated using the first and second offsets; and f) determining a radius of the cutting end based on the first, second, third and fourth coordinates.
[0008] In yet another aspect, there is provided a turning machine comprising: a tool having a cutting end; a touch probe having two flat faces and one of a rounded and angled corner joining the two flat faces; and an electronic control unit (ECU) controlling the one of the tool and the probe to move in a reference frame to establish separate contacts between the probe and the tool at a first point on one of the two flat faces, at a second point on the other one of the two flat faces and at a third point on the one of the rounded and angled corner, the ECU being configured to record coordinates of a reference point of the one of the tool and the probe during the separate contacts so as to calculate a radius of the cutting end.
DESCRIPTION OF THE DRAWINGS
[0009] Reference is now made to the accompanying figures in which:
[0010] FIG. 1 is a schematic view of a tool for a turning machine;
[0011] FIG. 2 a is a schematic top plan view of a touch probe according to a first embodiment;
[0012] FIG. 2 b is a schematic top plan view of a touch probe according to a second embodiment;
[0013] FIG. 3 is a schematic view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in a first position relative to each other;
[0014] FIG. 4 is a schematic view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in a second position relative to each other;
[0015] FIG. 5 is a schematic view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in a third position relative to each other;
[0016] FIG. 6 is a schematic view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in a fourth position relative to each other;
[0017] FIG. 7 a is a close-up view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in a fifth position relative to each other;
[0018] FIG. 7 b is a close-up view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in the fourth position relative to each other shown in FIG. 6 ;
[0019] FIG. 8 is a flow chart of a method of determining a radius of the tool of FIG. 1 using any one of the touch probes of FIG. 2 a or 2 b ; and
[0020] FIG. 9 is a close-up view of the tool of FIG. 1 and the touch probe of FIG. 2 a shown in a sixth position relative to each other.
DETAILED DESCRIPTION
[0021] Referring to FIG. 1 , a tool 10 for a turning machine is shown. The tool 10 includes a body 12 and a cutting portion 14 for use, for example, in in-turn or mill-turn machines, the machines also being known as lathes, CNC, turning machines etc. The cutting portion 14 has a cutting end 16 . The tool 10 may be used to manufacture parts, such as metallic components, by carving out portions of the rotating part using the tool 10 . The parts may then be used in a variety of industries including the aeronautics industry. In turning machines, the parts are cylindrical, revolve about their centerline with the tool 10 abutting on their external surface. The cutting end 16 of the tool 10 creates an indentation. As the tool 10 is moved deeper into the rotating part, material is removed from the part and various cut-outs and channels can be created. A position of the cut-out is predetermined in function of a desired shape of the part, and the tool 10 is moved by the turning machine in a precise fashion to accomplish the desired shape of the part. This is commonly known as grooving, and other operations are possible as well, such as facing and face grooving.
[0022] The cutting end 16 may have various shapes and be more or less sharp depending on the desired shape of the part. Whatever the sharpness of the cutting end 16 , it includes a rounded portion at the tip. The rounded portion may be approximated by a portion of a circle C (a close-up view on the cutting end 16 showing the circle C is shown in FIG. 7 a ). For smaller cut-outs where precision may be even more desired, an actual radius R of the cutting end 16 may be a desirable information. While a radius of the cutting end 16 may be obtained from a manufacturer of the cutting portion 14 (i.e. nominal value), there may be a discrepancy between the nominal value and the actual value of the radius R of the cutting end 16 . This discrepancy may cause a discrepancy between the desired shape of the part and the obtained shape of the part.
[0023] In order to decrease a potential discrepancy between the nominal value and the actual value of the radius R of the cutting end 16 , the tool 10 may be tested to determine the actual value of the radius R of the cutting end 16 prior to use on the part. The method by which the actual value of the radius R of the cutting end 16 is determined will be described below. The method includes the determination of coordinates of various points along the cutting end 16 using a touch probe.
[0024] Turning now to FIGS. 2 a and 2 b , FIG. 2 a shows a first embodiment of a touch probe 22 for use in the determination of the actual value of the radius R of the cutting end 16 . The touch probe 22 has a generally square cross-section with rounded corners and is shown in FIG. 2 in a top plan view (e.g. cubic shape, rectangular prism shape). The touch probe 22 includes at least four flat sides, namely sides 24 , 26 , 28 , 30 and four rounded corners, namely corners 32 , 34 , 36 , 38 . The corners 32 , 34 , 36 , 38 have a same radius of curvature, but it is contemplated that the corners 32 , 34 , 36 , 38 could each have a different radius of curvature. Typically, the touch probe 22 deflects when touching an object. Touching one side 24 , 26 , 28 , 30 or one corner 32 , 34 , 36 , 38 gives a signal to the machine controller to record the actual positions. The touch probe 22 is linked to an electronic control unit (ECU) (not shown) which may record information every time the touch probe 22 sends a signal corresponding to one of the sides 24 , 26 , 28 , 30 or corners 32 , 34 , 36 , 38 being in physical contact with an object.
[0025] The touch probe 22 includes various sides 24 , 26 , 28 , 30 and corners 32 , 34 , 36 , 38 allowing the use of the touch probe 22 in a variety of direction and positions without having to greatly manipulate it, such as rotating it. With the use of the sides 24 , 26 , 28 , 30 and corners 32 , 34 , 36 , 38 , the touch probe 22 could be used in at least 8 orientations of the tool 10 relative to the touch probe 22 in a 360° circumference.
[0026] The touch probe 22 shown in FIG. 2 a is only one example of touch probe adapted for the below method of determining the radius R of the cutting end 16 . FIG. 2 b shows a second embodiment of a touch probe 22 ′ for use in the determination of the actual value of the radius R of the cutting end 16 . The touch probe 22 ′ is similar to the touch probe 22 except that it features angled corners 32 ′, 34 ′, 36 ′, 38 ′ in place of rounded corners 32 , 34 , 36 , 38 in between flat sides 24 ′, 26 ′, 28 ′, 30 ′. The angled corners 32 ′, 34 ′, 36 ′, 38 ′ are disposed at 45 degrees of the flat sides 24 ′, 26 ′, 28 ′, 30 ′. Other angular orientations of the angled corners 32 ′, 34 ′, 36 ′, 38 ′ are contemplated. It is contemplated that the touch probe 22 could yet have other shapes. For example, the touch probe 22 could have a triangular or rectangular cross-section instead of a square cross-section. The touch probe 22 could also have only one side.
[0027] Turning to FIG. 3 , the tool 10 is shown in relation with the touch probe 22 for proceeding to the determination of the radius R of the cutting end 16 . The touch probe 22 is used in a turning machine (not shown) with the tool 10 located as it would be to carve a part. It is however contemplated that the touch probe 22 and the tool 10 could be used outside of the turning machine to determine the radius R of the cutting end 16 of the tool 10 . The turning machine has a fixed reference frame RF which defines a X-axis and an in-plane Z-axis. In the embodiment described in relation to the Figures, the touch probe 22 is oriented to have its sides 24 , 26 , 28 , 30 aligned with the X- and Z-axes of the reference frame RF. The touch probe 22 and the tool 10 may move in a plane of the X- and Z-axes relative to one another.
[0028] The touch probe 22 allows determining coordinates of several points P 1 , P 2 , P 3 of the cutting end 16 (shown best in FIG. 7 a ) relative to a reference point P 0 of the tool 10 to later calculate the radius R of the cutting end 16 . In the embodiment described herein, the reference point P 0 is a fixed point of the tool 10 and is movable within the reference frame RF. An ECU (which may or may not be a same ECU as the one linked to the touch probe 22 ) records the position of the reference point P 0 at all times t: (P 0 t (X),P 0 t (Z)). From the position of the reference point P 0 at all times and coordinates of the touch probe 22 which may be known from calibration, can be deduced the coordinates of the points P 1 , P 2 , P 3 of the cutting end 16 . As shown in FIG. 3 , the tool 10 may use 3 different paths, namely path 1 , path 2 , path 3 , to contact the touch probe 22 at three associated locations, in this embodiment sides 24 , 26 and corner 32 .
[0029] An out-of-plane Y-axis may also be defined, the X,Y,Z-axes forming together an orthogonal reference frame. The tool 10 has a reference point P 0 which allows determining a position of the tool 10 in the reference frame RF. In the example described herein, the touch probe 22 is fixed relative to the reference frame RF, while the tool 10 is movable relative to the reference frame RF. It is contemplated that the tool 10 could be fixed relative to the reference frame RF, while the touch probe 10 could be movable relative to the reference frame RF.
[0030] Turning now to FIGS. 4 to 8 , a method 40 of determining the radius R of the cutting end 16 will be described. FIGS. 4 to 7 b show different positions of the tool 10 relative to the touch probe 22 , and FIG. 8 is a flow chart with the different steps of the method 40 .
[0031] The method 40 starts at step 42 by a contact between the tool 10 and the touch probe 22 at a first point P 24 having a known position on the X-axis and recording a coordinate of the reference point P 0 of the tool on the X-axis ( FIG. 4 ).
[0032] Referring more specifically to FIGS. 3 and 4 , a numerical command moves the tool 10 along the path 1 based on information obtained during calibration. Calibration information include a position of the side 24 in the reference frame RF on the X-axis, X 24 . Motion of the tool 10 stops when the tool 10 contacts the side 24 of the touch probe 22 . As the point P 1 of the cutting end 16 contacts the touch probe 22 (time t=t 1 ) at point P 24 , the touch probe 22 triggers an electrical signal which commands the tool 10 to stop its course. Coordinates of the reference point P 0 are then read and the X-coordinate of the reference point P 0 , P 0 t=t1 (X), is recorded by the ECU. The side 24 being aligned with the Z-axis, any point of the side 24 has a same X-coordinate X 24 . Although the cutting end 16 is shown in FIG. 4 contacting a middle of the side 24 (i.e. point P 24 ), it should be understood that the cutting end 16 may contact any point along the side 24 . It is also contemplated that the side 28 could have been used in place of the side 24 of the touch probe 22 .
[0033] From the determination of P 0 t=t1 (X), various values can be obtained. These values may be obtained by the ECU at step 42 or at a later step.
[0034] At time t=t 1 , the X-coordinate of the point P 1 , P 1 t=t1 (X) is equal to the X-coordinate X 24 of the point P 24 .
[0035] From P 0 t=t1 (X) and P 1 t=t1 (X) can be deduced a position of the first point P 1 relative to the reference point P 0 , i.e. an offset Off X of the cutting end 16 on the X-axis.
[0000] Off X =P 1 t=t1 ( X )− P 0 t=t1 ( X ) (Eq. 1)
[0036] Since, at time t=t 1 , P 1 t=t1 (X) is equal to X 24 ,
[0000] Off X =X 24 −P 0 t=t1 ( X ) (Eq. 2)
[0037] The offset Off X may be used to deduce the radius R of the cutting end 16 in a below step.
[0038] The offset Off X being known, the X-coordinate of the first point P 1 can be known at all times.
[0000] P 1 t ( X )= P 0 t ( X )+Off X (Eq. 3)
[0039] When the value of P 0 t=t1 (X) is recorded and optionally the value of the offset Off X obtained at this step, the touch probe 22 is moved back to its original position shown in FIG. 3 so as to undo the contact between the touch probe 22 and the tool 10 .
[0040] From step 42 , the method 40 goes to step 44 , to contact the touch probe 22 at a second point P 26 having a known position on the Z-axis and recording a coordinate of the reference point P 0 of the tool on the Z-axis.
[0041] Referring more specifically to FIG. 5 , a numerical command moves the tool 10 along the path 2 based on information obtained during calibration. Calibration information include a position of the side 26 in the reference frame RF, Z 26 . Motion of the tool 10 stops when the tool 10 contacts the side 26 of the touch probe 22 . As the point P 2 of the cutting end 16 contacts the point P 26 of the touch probe 22 (time t=t 2 ), the touch probe 22 triggers an electrical signal which commands the tool 10 to stop its course. Coordinates of the reference point P 0 are read and the Z-coordinate of the reference point P 0 , P 0 t=t2 (Z), is recorded by the ECU. The side 26 being aligned with the X-axis, any point of the side 26 has a same Z-coordinate Z 26 . Although the cutting end 16 is shown in FIG. 5 contacting a middle of the side 26 (i.e. point P 26 ), it should be understood that the cutting end 16 may contact any point along the side 26 . It is also contemplated that the side 30 could have been used in place of the side 26 of the touch probe 22 .
[0042] From the determination of P 0 t=t2 (Z), various values can be obtained. These values may be obtained by the ECU at step 44 or at a later step.
[0043] At time t=t 2 , the Z-coordinate of the point P 2 , P 2 t=t2 (Z) is equal to the Z-coordinate Z 26 of the point P 26 .
[0044] From P 0 t=t2 (Z) and P 2 t=t2 (Z) can be deduced a position of the point P 2 relative to the reference point P 0 , i.e. an offset Off Z of the cutting end 16 on the Z-axis.
[0000] Off Z =P 2 t=t2 ( Z )− P 0 t=t2 ( Z ) (Eq. 4)
[0045] Since, at time t=t 2 , P 2 t=t2 (Z) is equal to Z 26 ,
[0000] Off Z =Z 26 −P 0 t=t2 ( Z ) (Eq. 5)
[0046] The offset Off Z may be used to deduce the radius R of the cutting end 16 in a below step.
[0047] The offset Off Z being known, the Z-coordinate of the point P 2 can be known at all times.
[0048] When the value of P 0 t=t2 (Z) is recorded and optionally the value of the offset Off Z obtained at this step, the touch probe 22 is moved back to its original position shown in FIG. 3 so as to undo the contact between the touch probe 22 and the tool 10 .
[0049] Steps 42 and 44 could be performed in any order, and by a same probe or two distinct probes.
[0050] From step 44 , the method 40 goes to step 46 , to contact the touch probe 22 at a third point P 32 having a known position on the X- and Z-axes and record a coordinate of the reference point P 0 of the tool on the X- and Z-axes. The point P 32 is not aligned with the sides 24 or 26 , and as such has a X-coordinate different from the X-coordinate of the point P 24 , and a Z-coordinate different from the Z-coordinate of the point P 26 .
[0051] Referring more specifically to FIGS. 6, 7 a and 7 b , a numerical command moves the tool 10 along the path 3 based on information obtained during calibration and information obtained at steps 42 and 44 . Calibration information includes a position of the point P 32 , namely X 32 , Z 32 , in the reference frame RF and the numerical command moves the tool 10 to contact specifically the point P 32 . The point P 32 is in a predetermined direction PD which is in-plane with the X- and Z-axes and at an angle α with respect to the X- and Z-axes. The angle α is determined at calibration. In one embodiment, the angle α is 45 degrees. Information obtained at steps 42 and 44 include Off x and Off Z which allow deducing the coordinates of a virtual cutting end point P CE , defined as the intersection of a line parallel to the X-axis passing through P 2 and a line parallel to the Z-axis passing through P 3 . The numerical command includes travelling the point P CE onto the predetermined direction PD.
[0052] Motion of the tool 10 stops when the point P 3 of the cutting end 16 contacts the point P 32 of the touch probe 22 . As the tool 10 contacts the touch probe 22 at time t=t 3 , the touch probe 22 trigger and electrical signal which commands the tool 10 to stop its course. Coordinates of the reference point P 0 are read and the X- and Z-coordinates of the reference point P 0 t=t3 (X), P 0 t=t3 (Z) and recorded by the ECU. It is contemplated that the corners 34 , 38 or 38 could have been alternatively used.
[0053] The coordinates of the reference point P 0 t=t3 (X), P 0 t=t3 (Z) may be used to deduce the radius R of the cutting end 16 in a below step.
[0054] From step 46 , the method 40 goes to step 48 , to determine the radius R of the cutting end 16 by the ECU.
[0055] As best seen in FIG. 7 b , when the cutting end 16 contacts the corner 32 at the point P 32 , the radius R may be obtained by:
[0000] R=d (1+√{square root over (2)}) (Eq. 6)
[0056] when the angle α is 45°, d being a distance between third point P 32 and the virtual cutting end point P CE . The virtual cutting end point P CE is defined as the intersection between a line parallel to the X-axis passing through the point P 2 with a line parallel to the Z-axis passing through the point P 1 .
[0000] d =√{square root over (( P CE t=t3 ( X )− X 32 ) 2 +( P CE t=t3 ( Z )− Z 32 ) 2 )} (Eq. 7)
[0057] The cutting end point P CE has a same X-coordinate as the first point P 1 and a same Z-coordinate as the second point P 2 :
[0000] P CE t=t3 ( X )= P 1 t=t3 ( X )= P 0 t=t3 ( X )+Off X
[0000] P CE t=t3 ( Z )= P 2 t=t3 ( Z )= P 0 t=t3 ( Z )+Off Z (Eq. 8)
[0058] Which leads to:
[0000]
d
=
(
P
0
t
=
t
3
(
X
)
+
Off
X
-
X
32
)
2
+
(
P
0
t
=
t
3
(
Z
)
+
Off
Z
-
Z
32
)
2
(
Eq
.
9
)
[0059] From which the radius R is deduced as:
[0000]
R
=
(
P
0
t
=
t
3
(
X
)
+
Off
X
-
X
32
)
2
+
(
P
0
t
=
t
3
(
Z
)
+
Off
Z
-
Z
32
)
2
(
1
+
2
)
(
Eq
.
10
)
[0060] when the angle α is 45°. Determination of the radius R when the angle α is not 45° will be given below.
[0061] Step 46 could be performed by the same probe as steps 42 and/or 44 or by a distinct probe.
[0062] The above method relies on the knowledge of the parameters X 24 , Z 26 , X 32 , Z 32 , which may be determined during a calibration step prior to the method 40 .
[0063] During calibration, a calibration tool having known dimensions is used. The calibration tool may or may not be similar to the tool 10 . The calibration tool has the reference point P 0 which coordinates in the reference frame RF are recorded at all time. The cutting end of the calibration tool is brought into contact with the side 24 , the X-coordinate of the reference point P 0 is recorded, and the X-coordinate X 24 is determined to be the sum of the X-coordinate of the reference point P 0 and a known distance between a point of the cutting end contacting the side 24 and the reference point P 0 . Similarly, the cutting end of the calibration tool is brought in a second time into contact with the side 26 , the Z-coordinate of the reference point P 0 is recorded, and the Z-coordinate Z 26 is determined to be the sum of the Z-coordinate of the reference point P 0 and a known distance between a point of the cutting end contacting the side 26 and the reference point P 0 .
[0064] To calibrate the corner 32 and determine the parameters X 32 , Z 32 , the predetermined direction PD is first determined. In one embodiment, the predetermined direction PD is disposed at 45° from the X- and Z-axes. In other embodiment, the predetermined direction PD is disposed at an angle other than 45° from the X- and Z-axes.
[0065] With reference to FIG. 9 , should the predetermined direction PD not be at 45°, the calibration process would define the radius PR of the arc A formed by the probe corner 32 , 34 , 36 , 38 and the center coordinates PC of the arc A. The position of the contact point P 32 on the touch probe 20 may change according to the approach direction and the tool radius size. It may be identified by the calibration as for the case of 45°. When the tool touches the probe, the coordinate of PCE in X and Z directions are recorded. With reference to FIG. 9
[0000]
(
d
z
d
x
)
=
PCE
-
PC
,
d
z
=
PCE
z
-
PC
z
,
and
d
x
=
PCE
x
-
PC
x
.
[0000] The angular position of the contact point on the probe arc A depends on the tool radius size. From the geometry, when the probe is in contact with the cutting tool:
[0000] ( PR+R ) 2 =( R+d z ) 2 +( R+d x ) 2 (Eq. 11)
[0000] The unknown parameter in this equation is the tool radius R. The solution of this equation gives TR as:
[0000] R =( PR−d z −d x )+√{square root over (( PR−d x −d z ) 2 +PR 2 −d x 2 −d z 2 )} (Eq. 12)
[0066] In the case of angle=450, as discussed above, geometrically we have:
[0000] ( R+d ) 2 =( R ) 2 +( R ) 2 (Eq. 13).
[0067] The solution of this equation gives TR as:
[0000] R=d (1+√{square root over (2)}) where
[0000]
d
=
(
P
0
t
=
t
3
(
X
)
+
Off
X
-
X
32
)
2
+
(
P
0
t
=
t
3
(
Z
)
+
Off
Z
-
Z
32
)
2
[0000] as discussed above.
[0068] Using the above method, relatively small radii R of the cutting end 16 such as the one commonly found in in-turn and mill-turn applications, can be determined. In one embodiment, the radius R is smaller than 0.1 inch. In one embodiment, the radius R is comprised between 0.01 and 0.1 inch. The above method may be carried within the turning machine which reduces a number of steps to determine the radius R. The relatively non-invasive method described above also allows determining the radius at any time before a turning operation without removing the tool 10 from the machine.
[0069] The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. For example, the method could be used for tool not related to turning machines. The method could be used with any tool having an arcuate portion, and could preferably be used with tools of relatively small radii. Still other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.
|
A method of determining a radius of a cutting end of a tool for a turning machine using a touch probe is provided. One of the cutting end and the touch probe is movable relative to a reference frame having a first axis and a second axis and having a reference point trackable in the reference frame. The method comprises establishing a first contact point and recording a first coordinate of the reference point on the first axis; establishing a second contact point and recording a second coordinate of the reference point on the second axis; establishing a third contact point and recording a third coordinate of the reference point on the first axis and a fourth coordinate of the reference point on the second axis upon contact; and determining a radius of the cutting end based on the first, second, third and fourth coordinates.
| 6
|
RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 12/809,522 filed Jun. 18, 2010, now issued as U.S. Pat. No. 8,686,407 on Apr. 15, 2014, which is a 371 of International Patent Application No. PCT/US2008/068412 filed Jun. 26, 2008 which in turn claims benefit to U.S. Provisional Patent Application No. 61/016,294 filed Dec. 21, 2007.
BACKGROUND
Cutting tools are used in a variety of applications to cut or otherwise remove material from a workpiece. A variety of cutting tools are well known in the art, including but not limited to knives, scissors, shears, blades, chisels, machetes, saws, drill bits, etc.
A cutting tool often has one or more laterally extending, straight or curvilinear cutting edges along which pressure is applied to make a cut. The cutting edge is often defined along the intersection of opposing surfaces (bevels) that intersect along a line that lies along the cutting edge.
In some cutting tools, such as many types of conventional kitchen knives, the opposing surfaces are generally symmetric; other cutting tools, such as many types of scissors, have a first opposing surface that extends in a substantially normal direction, and a second opposing surface that is skewed with respect to the first surface. More complex geometries can also be used, such as multiple sets of bevels at different respective angles that taper to the cutting edge. Scallops or other discontinuous features can also be provided along the cutting edge, such as in the case of serrated knives.
Cutting tools can become dull over time after extended use, and thus it can be desirable to subject a dulled cutting tool to a sharpening operation to restore the cutting edge to a greater level of sharpness. A variety of sharpening techniques are known in the art, including the use of grinding wheels, whet stones, abrasive cloths, etc. A limitation with these and other prior art sharpening techniques, however, is the inability to precisely define the opposing surfaces at the desired angles to provide a precisely defined cutting edge.
SUMMARY
Various embodiments of the present invention are generally directed a method and apparatus for sharpening a cutting tool.
In accordance with some embodiments, an endless belt has an abrasive outer surface and a backing layer inner surface. The endless belt is held in tension along a planar extent extending along a neutral plane between spaced apart first and second rollers against which the backing layer inner surface contactingly passes during continuous rotation of the belt along a routing path. A guide assembly adjacent the planar extent of the belt comprises spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. The first guide surface extends at an acute angle with respect to the second guide surface and the base surface extends at an obtuse angle with respect to the first guide surface. The guide assembly is configured such that during insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is configured to be contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.
In other embodiments, an endless belt has an abrasive outer surface and a backing layer inner surface. The endless belt held in tension along a planar extent extending along a neutral plane between spaced apart first and second rollers against which the backing layer inner surface contactingly passes during continuous rotation of the belt along a routing path. A tensioner assembly attached to at least one of the first or second rollers supplies a first tension force to the belt while the planar extent is aligned along the neutral plane. A guide assembly adjacent the planar extent of the belt comprises spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. The guide assembly is configured such that during insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is configured to be contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface. The tensioner assembly supplies a greater, second tension force to the belt while the first portion of the cutting edge is contacting the base surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B provide respective isometric and side elevational views of a cutting tool sharpener system (sharpener) constructed in accordance with various embodiments of the present invention.
FIG. 2 shows the sharpener of FIGS. 1A-1B with a guide housing removed to expose various features of interest including an abrasive belt and three rollers.
FIG. 3 is a schematic depiction of FIG. 2 .
FIG. 4A provides an end view of the arrangement of FIG. 3 with the use of crowned rollers.
FIG. 4B provides an alternative end view of the arrangement of FIG. 3 with the use of guide rollers.
FIGS. 5A and 5B show side and top plan views of portions of a first belt.
FIGS. 6A and 6B show side and top plan views of portions of a second belt.
FIGS. 7A and 7B provide schematic depictions of the sharpener to generally illustrate a twisting (localized torsion) of the unsupported abrasive belt during a sharpening operation upon a cutting tool.
FIGS. 8A and 8B generally illustrate different torsion effects that may be encountered by the abrasive belt during the sharpening of the cutting tool of FIG. 7 .
FIG. 9 shows a sharpening guide of the sharpener guide housing in greater detail.
FIGS. 10A-10C generally depict a progression of symmetrical sharpening operations that may be advantageously performed upon a cutting tool to provide the tool with a desired final geometry.
FIG. 11 generally illustrates asymmetrical sharpening operations upon a cutting tool to provide a final desired geometry.
FIGS. 12A and 12B illustrate additional types of cutting tools with various cutting edge features that can be sharpened using the sharpener.
FIG. 13 shows relevant portions of the sharpener in accordance with another embodiment configured to sharpen other types of cutting tools.
FIG. 14 shows a side elevational view of FIG. 13 .
FIG. 15 provides a flow chart for a SHARPENING OPERATION routine generally illustrative of steps carried out in accordance with preferred embodiments of the present invention.
DETAILED DESCRIPTION
FIGS. 1A and 1B generally depict an exemplary cutting tool sharpener system 100 (“sharpener”) constructed in accordance with various embodiments of the present invention. The sharpener 100 is configured to sharpen a number of different types of cutting tools in a fast and efficient manner.
The sharpener 100 includes a main drive assembly 102 with a housing 104 which encloses a drive assembly (generally denoted at 105 ). The drive assembly 105 can take any suitable configuration depending on the requirements of a given application. Preferably, the drive assembly 105 includes an electric motor which rotates at a selected rotational rate.
Suitable gearing or other torque transfer mechanisms can be used to provide a final desired rotational rate. In some embodiments, the rate and/or the direction of rotation can be adjusted, either automatically or manually by the user, for different sharpening operations. User control switches are generally depicted at 106 .
The sharpener 100 further generally includes a sharpening assembly 108 coupled to the drive assembly. The sharpening assembly 108 preferably includes a substantially triangularly-shaped guide housing 110 with opposing sharpening guides 112 extending therein. The guides 112 enable a particular cutting tool, such as a kitchen knife 114 , to be alternately presented to the sharpener 100 from opposing sides.
FIG. 2 provides another view of the sharpener 100 of FIGS. 1A and 1B . In FIG. 2 , the guide housing 110 has been removed to reveal a continuous, flexible abrasive belt 116 which is routed around rollers 118 , 120 and 122 . The roller 118 is characterized as a drive roller which is powered by the aforementioned drive assembly. The roller 120 is a fixed idler roller, and the roller 122 is a spring biased idler roller with an associated tensioner assembly 124 .
The tensioner assembly 124 preferably includes a coiled spring 126 or other biasing mechanism which applies an upwardly directed tension force upon the belt, as generally depicted in FIG. 3 . The rollers 118 , 120 and 122 are preferably crowned to maintain centered tracking of the belt 116 , as generally represented in FIG. 4A , although guide rollers can additionally or alternatively be used, as generally represented in FIG. 4B . While a substantially triangular path for the belt 116 is preferred, such is not necessarily required as any number of other arrangements can be used as desired.
For example, in an alternative embodiment the belt 116 is routed around just two rollers rather than the three shown in FIG. 3 . The rollers can be the same diameter to provide a substantially oval shaped path, or a larger roller can be used in lieu of the two lower rollers shown in FIG. 3 to maintain a substantially triangular path. More than three rollers can also be used to provide other path configurations. It will be appreciated that in each of these embodiments, the system can be characterized as aligning the belt along a first selected plane between first and second supports (e.g., such as on the left hand side of FIG. 3 ), and aligning the belt along a second selected plane between a third support and the first support (e.g., such as on the right hand side of FIG. 3 ).
The belt 116 nominally rotates at a speed and direction around the rollers 118 , 120 , 122 as determined by the operation of the drive assembly. It is contemplated that a population of belts will be supplied for use with the sharpener 100 , each belt having different physical characteristics and each being easily removable from and replaceable onto the sharpener 100 in turn.
By way of illustration, FIGS. 5A and 5B provide respective side and top views of a first belt 116 A. The belt 116 A preferably includes a layer of abrasive material 128 A affixed to a backing (substrate) layer 130 A. The abrasive layer can take any number of forms, such but not limited to diamond particles, sandpaper material, etc., and will have a selected abrasiveness level (roughness). The backing layer 130 A can similarly be selected from a wide variety of materials, such as cloth, plastic, paper, etc.
In the present example, the first belt 116 A is contemplated as having an abrasiveness level on the order of about 400 grit. It is contemplated that the relative width, thickness and roughness of the first belt 116 A will make the belt suitable for initial grinding operations upon the cutting tool in which relatively large amounts of material are removed from the tool.
FIGS. 6A and 6B show a second exemplary belt 116 B. The second belt 116 B also has an abrasive layer 128 B and a backing layer 130 B. The abrasive layer 128 B is contemplated as comprising a finer grit than that of the first belt 116 A, such as order of about 1200 grit. The exemplary second belt 116 B is contemplated as being generally more flexible than the first belt 116 A.
The second belt 116 B is shown to be narrower than the first belt 116 A, to demonstrate that the sharpener 100 can be readily configured to accommodate different widths of belts. However, in preferred embodiments, all of the belts utilized by the sharpener 100 will have nominally the same width and length dimensions. Further, for reasons that will be discussed below, it is preferred that belts of coarser grit (such as the first belt 116 A) will be configured to have successively higher levels of linear stiffness, whereas belts of finer grit (such as the second belt 116 B) will be configured to have successively lower levels of linear stiffness.
As used herein, the term “linear stiffness” generally relates to the ability of the belt to bend (displace) along the longitudinal length of the belt (i.e., in a direction along the path of travel) in response to a given force. Generally, a belt with a higher linear stiffness will provide a larger radius of curvature as it is deflected by an object, since the belt has a relatively lower amount of flexibility along its length. Conversely, a belt with a lower linear stiffness, due to its relatively higher level of flexibility, will provide a smaller radius of curvature as it is deflected by the same object.
Accordingly, the second belt 116 B is particularly suited for subsequent grinding or honing operations upon the cutting tool in which relatively smaller amounts of material are removed from the tool. It will be appreciated that the relative dimensions represented in FIGS. 5-6 are merely exemplary in nature and are not limiting. For example, all of the belts may be of the same general thickness with different flexibilities established by other characteristics, such as the material used to form the belts, the composition of the backing layers, etc. Also, any number of additional belts can be provided with other dimensions and levels of abrasiveness, including belts with a grit of 40 or lower, belts with a grit of 2000 or higher, etc.
It is contemplated that all of the belts will have generally the same circumferential length, but this is also not necessarily required as at least some differences in belt length can be accommodated via the tensioner 124 . Indeed, as will now be explained beginning with FIGS. 7A-7B , a number of factors including the tensioner force and the belt length, width, thickness and stiffness are preferably selected to provide specifically controlled amounts of linear and torsional deflection of the belt during sharpening.
FIGS. 7A and 7B provide schematic representations of the sharpener 100 to illustrate preferred operation of a selected belt 116 during a sharpening operation upon a cutting tool 132 . FIG. 7A shows the cutting tool 132 prior to engagement with the belt 116 , and FIG. 7B shows the cutting tool 132 during engagement with the belt 116 .
For reference, the cutting tool 132 is shown in a canted orientation, and for purposes of the present example the cutting tool is characterized as a conventional kitchen knife with handle 134 , blade 136 and curvilinearly extending cutting edge 138 .
As shown in FIG. 7B , the belt 116 preferably twists out of its normally aligned plane, as indicated by torsion arrow 140 , in the vicinity of the knife 132 as the cutting edge 138 is drawn across the belt 116 . More specifically, the user preferably grasps the handle 134 and pulls the knife 132 back in a substantially linear fashion, as indicated by arrow 141 . The moving belt 116 will undergo localized torsion (twisting) to maintain a constant angle of the abrasive layer 128 against the blade 136 irrespective of the specific shape of the cutting edge 136 . In this way, a constant and consistent grinding plane can be maintained with respect to the blade material.
The amount of torsional displacement of the belt along a particular cutting edge can vary widely in relation to changes in the curvilinearity of the cutting edge. A typical amount of twisting may be on the order of 30 degrees or more out of plane. In extreme cases such as when the distal tip of a blade passes across the belt, twisting of up to around 90 degrees or more out of plane may be experienced. The torsion is generally a function of the length of the extent of the belt presented to the tool in comparison to the belt width, as well as a function of the tension applied to the belt applied by the tensioner assembly 124 . Thus, it is contemplated that, generally, each of the belts respectively installed onto the sharpener 100 will undergo substantially the same amount of torsion irrespective of the abrasiveness or linear stiffness of the belt.
The direction of belt twist will be influenced by the relation of the cutting edge 138 to the belt 116 . In FIG. 8A , a first portion 142 of the cutting edge 138 at the base of the blade 136 adjacent the handle 134 is generally concave with respect to the belt 116 . This will generally induce torsion in a counter-clockwise direction, as indicated by arrow 144 , as that portion of the blade passes adjacent the belt 116 .
In FIG. 8B , a second portion 146 of the cutting edge 138 near the point of the blade 136 is generally convex with respect to the belt 116 . Passage of the second portion 146 adjacent the belt will generally induce torsion in the opposite clockwise direction, as indicated by arrow 148 .
In a preferred embodiment, the retraction of the knife 132 across the belt 116 is controlled by the aforementioned sharpening guides 112 in the guide housing 108 ( FIG. 1 ). One of the guides 112 is generally depicted in FIG. 9 . A slot is formed by facing surfaces 150 , 152 and a base surface 154 , although other configurations can be used, including angled surfaces that form a v-shape. During the sharpening steps of FIGS. 8A and 8B , the knife 132 is inserted into the slot above the belt 116 and moved downwardly until the base of the cutting edge 138 (portion 142 in FIG. 8A ) comes into contacting abutment against the base surface 154 (also referred to as a cutting edge guide surface).
While maintaining a small amount of downward pressure upon the handle 134 , the user slowly draws the knife 132 back (i.e., direction 141 in FIGS. 8A-8B ) so that the cutting edge 138 remains in contact with, and slides against, the base surface 154 . Preferably, the blade 136 is also lightly pressed against the vertical guide surface 152 so as to slidingly pass in contacting engagement with the surface 152 during the sharpening operation.
Although not shown in FIG. 9 , a suitable retention feature, such as a spring clip or a magnet, can be incorporated into the guide 112 to maintain the knife 132 in contacting engagement with the surfaces 152 , 154 . The knife 132 is preferably passed across the belt several times in succession, such as 3-5 times, to sharpen a first side of the blade 136 . The knife 132 is then preferably moved to the other guide (see FIG. 1 ) and these steps are repeated to sharpen the other side of the blade 136 .
In some embodiments, the belt continues to rotate in a common rotational direction so that the belt moves “downwardly” with respect to the cutting tool on one side and “upwardly” with respect to the cutting tool on the other side. In other embodiments, the belt rotational direction is changed so as to pass downwardly on both sides, thereby drawing material down and past the cutting edge on both sides of the blade. Such change in belt rotational direction is not required in order to achieve effective levels of “razor” sharpness of the tool, but may be nevertheless be found to be beneficial in some applications. In such case, it is contemplated that the alternative directions of belt rotation can be manually set by the user, or automatically implemented by the sharpener 100 such as, for example, from the incorporation of a pressure switch or a proximity switch in each of the guides 112 to sense the presence of the cutting tool therein.
FIGS. 10A-10C generally illustrate a preferred sharpening sequence upon a blade 160 . As will be recognized by those skilled in the art, the ability to obtain a superior sharpness for a given cutting tool will depend on a number of factors, including the type of material from which the tool is made. It has been found that certain types of processed steel, such as high grade, high carbon stainless steel, are particularly suitable to obtaining sharp and strong cutting edges. It will be appreciated, however, that the sharpener 100 can be readily adapted to provide extremely sharp cutting edges for any number of materials, including relatively lower grades of steel, high quality Damascus steel, ceramic blades, tools made of other metallic alloys or non-metallic materials, etc.
As set forth by FIGS. 10A-10C , the sharpener 100 generates a novel, convex grind surface geometry. FIG. 10A shows the blade 160 in conjunction with a first belt 162 which, when alternately applied to opposing sides of the blade 160 , provides continuously extending, substantially convex surfaces 164 , 166 which converge and intersect along a cutting edge 168 . The first belt 162 is characterized as having a relatively coarse abrasive level, and relatively high linear stiffness characteristics.
FIG. 10B shows a subsequent grinding operation upon the blade 160 using a second belt 172 that forms opposing surfaces 174 , 176 and a cutting edge 178 . FIG. 10C is a side view depiction of the blade 160 at the conclusion of the operation of FIG. 10B . It will be appreciated that due to the torsional operation of the respective belts 162 , 172 , the cross-sectional geometries represented in FIGS. 10A-10B are nominally consistent along the entire longitudinal length of the blade (e.g., from substantially the tip of the blade to a position adjacent the handle).
The sharpening operation of FIG. 10A with the first belt 162 constitutes a relatively coarse, first stage grinding operation upon the blade material, and provides a relatively large radius of curvature upon the opposing sides 164 , 166 of the blade 160 . This radius of curvature (denoted as R 1 at 169 ) is primarily established as a result of the relatively higher linear stiffness of the belt 162 . Substantially this same radius of curvature is applied along the entire extent of the blade 160 . (It will be appreciated that the length of the radius R 1 is relatively large with respect to the scale of FIG. 10A , and therefore the origin of the radius does not fit on the page).
While the sharpening geometry of FIG. 10A can produce an extremely sharp cutting edge 168 , a limitation that may be experienced with this particular sharpening geometry is the fact that the blade 160 is relatively thin for a substantial extent of the width of the blade 160 . This can result in an undesirably weak blade that will deform, dull or break relatively easily if large forces are applied to the cutting edge 168 .
Accordingly, it is contemplated that at the conclusion of this first stage of the sharpening operation, the first belt 162 is preferably removed from the sharpener 100 and the second belt 172 is installed, as depicted in FIG. 10B . The blade 160 is once again presented to the sharpener 100 and the second belt 172 applies a relatively fine (honing) grind upon the blade 160 . This results in a correspondingly smaller radius of curvature (R 2 at 179 ) upon each of the surfaces 174 , 176 due to the reduced linear stiffness of the second belt 172 .
As before, the second belt 172 undergoes torsion as the blade 160 is drawn across the belt so that the smaller radius of curvature shown in FIG. 10B is consistently applied along the extent of the blade 160 . As noted above, the respective belts 162 , 172 will preferably undergo substantially the same amounts of torsion during the respective grinding operations.
The smaller radius of curvature established by the more flexible second belt 172 generally localizes the honing operation to the vicinity of the end of the blade 160 . The new cutting edge 178 (and the opposing surfaces 174 , 176 ) result from the removal of material in FIG. 10B over what was present at the conclusion of the operation of FIG. 10A .
The effects of this localized honing operation in the vicinity of the cutting edge 178 are depicted in FIG. 10C . Generally, score (scratch) marks 180 may be present on the blade as a result of the relatively more aggressive abrasive of the first belt 162 . The ends of these score marks 180 , however, may be honed out of the blade in the vicinity of the final cutting edge 178 as a result of the secondary sharpening operation.
An advantage of the secondary sharpening process set forth by FIG. 10B is that the blade 160 now has the slicing advantages provided by the first surfaces 164 , 166 of FIG. 10A , as well as greater blade strength due to the greater thickness in the vicinity of the cutting edge 178 resulting from the greater curvature of the second surfaces 174 , 176 .
While two belts have been discussed above, it will be appreciated that such is merely illustrative and not limiting. For example, sharpening can be accomplished using any number of belts of various abrasiveness and stiffness that are successively installed onto the sharpener 100 and utilized in turn. Conversely, sharpening operations can be effectively carried out using just a single belt of selected abrasiveness and stiffness.
For example, once the blade 160 has become dulled due to moderate use, all that may be required to restore the blade 160 to the sharpness of FIGS. 10B and 10C would be to re-present the blade 160 for sharpening against the second belt 172 , thereby realigning the material along the cutting edge 178 . Conversely, if greater wear or damage is incurred, the sharpness of the blade 160 can be restored by application of both belts 162 , 172 to the blade.
The two belt sharpening process of FIGS. 10A-10C is particularly suitable for relatively harder materials such as laminated and/or high carbon steels, or other materials with a relatively high Rockwell Hardness level (such as on the order of e.g., 60 or higher). Such materials are sufficiently strong and hard to be able to transition from the relatively coarse grinding provided by the first belt 162 to the relatively fine grinding provided by the second belt 172 without undergoing deformation or other effects that would cause deviation from the displayed geometries.
Indeed, subjecting such relatively hard material to just the second belt 172 would ultimately result in the cutting edge 178 , although such may require an extended period of time since the finer abrasiveness of the second belt will generally take longer to remove the requisite material from the blade to arrive at this final configuration. The use of multiple belts of varying abrasiveness is thus preferred for purposes of efficiency, but is not necessarily required. Similarly, it may be desirable to apply just the coarse grind of FIG. 10A for certain applications.
Softer materials such as lower grade steels with relatively lower Rockwell Hardness (such as on the order of, e.g., 45-50) may benefit from the use of higher numbers of sequential grinding stages. For example, a sequence of three different belts of 400 grit, 800 grit and 1200 grit may be respectively used in turn. This would tend to reduce the transitions between different belts, thereby reducing the risk of undesirably inducing folding or other deformations of the blade material in the vicinity of the cutting edge. Indeed, any number of belts, including 5-10 different belts or more, and belts of upwards of 2000 grit or more, can be progressively used as desired, depending on the requirements of a given application.
While the geometries set forth by FIGS. 10A-10B are symmetric, similar geometries can readily be established for asymmetric blades, such as an exemplary blade 200 shown in FIG. 11 . The asymmetric blade 200 is typical of certain types of cutting tools such as pocket or utility knives with scallops (serrations) along a portion thereof (not separately shown), as well as some types of shears, scissors, etc.
The blade 200 has a first surface 201 that extends in a substantially vertical direction, and an opposing second surface 202 that curvilinearly extends to provide a convex grind surface similar to the surface 174 in FIG. 10B . It will be appreciated that the asymmetric blade 200 can be readily sharpened simply by applying the aforementioned sharpening sequence to just the second surface 202 .
FIGS. 12A-12B provide further examples of tools that can be readily sharpened using the aforementioned sharpening sequence. FIG. 12A shows a first style of utility knife 204 with a blade 205 and handle 206 . The blade 205 includes opposing, curvilinearly extending cutting edges 207 and 208 . The cutting edge 207 further includes a concave recess 209 useful, for example, in cutting fibrous materials such as a rope. The knife 204 can be sharpened by the sharpener 100 simply by applying the sequence of FIGS. 10A-10B while the knife 204 is in the orientation of FIG. 12A (to sharpen edge 207 ), flipping the knife over, and repeating (to sharpen edge 208 ). The aforementioned torsional and bending characteristics of the respective belts are readily capable of providing so-called “razor” sharpness to the entire extents of the edges 207 and 208 .
FIG. 12B shows a second type of utility knife 210 with blade 211 and handle 212 . The blade 211 has a complex geometry with a lower curvilinear edge 213 , a straight cutting edge 214 , and scallops (localized serrations) 215 . The cutting edges 213 and 214 can be readily sharpened as set forth above. In many cases scallops such as 215 can also be sharpened, albeit in a manner similar to that shown in FIG. 11 . It will be noted, however, that the torsional stiffness and width of the belts may need to be adjusted in relation to the relative size of the scallops 215 in order to maintain substantially the same initial geometries of the scallops at the conclusion of the sharpening operation.
It will be noted at this point that complex geometries such as depicted in FIGS. 10-12 with maximum levels of sharpness can generally be obtained only to the extent that the sharpening angle (i.e., the angle between the tool and the abrasive) is maintained within close tolerances during each sharpening pass. Too much variation in the sharpening angle from one pass to the next can actually result in a cutting edge becoming duller as a result of the sharpening operation, since the variations prevent formation of the desired intersection of the respective opposing surfaces. This constitutes a major drawback with most prior art sharpeners.
Even state of the art sharpeners that employ multiple stages of guides and rotating grinding wheels to provide highly controlled sharpening operations are not immune to such variability. Such sharpeners will often require the user to rotate the tool as the tool is drawn back so that the tool takes a curvilinear path to match the curvilinear extent of the cutting surface. While such sharpeners may produce high levels of sharpness, it will be immediately apparent that variations will occur to the extent that the user does not (and cannot) draw the curved blade back at the exact same angle during each pass.
It will thus be seen that the sharpener 100 advantageously provides highly repeatable and controllable sharpening angles for substantially any shape cutting edge, since the sharpening angle is established and maintained by the adaptive torsion of the belt as it reacts to the differences in curvilinearity of the cutting edge. It has been found that sharpeners constructed in accordance with the exemplary sharpener 100 disclosed herein readily achieve levels of sharpness that exceed what is sometimes generally referred to in the art as “scary sharpness” (razor sharp, scalpel sharp, etc.) even for cutting tools with less-than superior metallic constructions.
While the various embodiments discussed above have been configured for the sharpening of bladed cutting tools, such as knives, which can be inserted into the guides 112 , it will be appreciated that any number of different types and styles of tools can be sharpened using the sharpener 100 by removal of the guide housing 110 ( FIG. 3 ) and presentation of the tool to the respective exposed extents of the belt 116 . Accordingly, any number of other styles and types of cutting tools, such as lawn mower blades, machetes, scissors, swords, spades, rakes, etc. can be effectively sharpened by the sharpener 100 in like manner to that discussed above.
An alternative embodiment for the sharpener 100 is generally depicted in FIG. 13 , which uses an alternative drive configuration and belt path for the belt 116 . Unlike the symmetric arrangement of FIG. 3 , the alternative arrangement of FIG. 13 provides an asymmetric triangular path for the belt. As before, the belt passes over rollers 118 , 120 , 122 and is tensioned by the tensioner 124 .
The arrangement of FIG. 13 provides only a single side of the belt for sharpening, such as for a cutting tool 216 characterized as a set of pruning shears. The shears 216 include spring biased handles 218 , 220 which, when closed, bring a blade portion 222 with cutting edge 224 into proximity with a shear portion 226 .
As further shown in FIG. 14 , the configuration of the shears is such that the cutting edge 224 lies in close relation to the intersection with the shear portion 226 , making the shears difficult to sharpen in this vicinity using conventional processes such as a grinding wheel, due to the lack of clearance. However, generally the only limiting factor with the sharpener 100 is the thickness of the belt 116 , so that substantially the entire extent of the cutting edge 224 can be sharpened without the need to disassemble the tool 216 . That is, in both the embodiments of FIGS. 3 and 13-14 , sufficient clearance is provided behind the belt 116 to provide a bypass clearance to enable a portion of the tool to be disposed behind the belt.
FIG. 15 provides a flow chart for a SHARPENING OPERATION routine 300 , generally illustrative of steps carried out in accordance with various preferred embodiments of the present invention. It will be appreciated that FIG. 15 generally summarizes the foregoing discussion.
Initially, at step 302 a first abrasive flexible belt (such as 116 A in FIGS. 5A-5B or 162 in FIG. 10A ) is selected and installed onto the sharpener 100 . This first abrasive belt will have a selected abrasiveness level and a selected linear stiffness as discussed above. Once installed, the first belt is driven at step 304 via the drive assembly 105 ( FIG. 1A ) in a selected direction along a selected plane between a first support and a second support (such as between the rollers 122 and 118 in FIG. 3 ).
At step 306 , a cutting tool (such as 114 , 132 , 204 , 210 , 216 , etc.) is presented in contacting engagement against the abrasive surface of the belt. This induces torsion of the belt out of the selected plane to conform to the cutting edge of the cutting tool (as generally depicted in FIGS. 7-8 ) and/or bending of the belt out of the selected plane at a radius of curvature determined in relation to said linear stiffness to shape a side surface of the cutting tool with said radius of curvature (as generally depicted in FIGS. 10A-10C ).
At this point it will be noted that while preferred embodiments configure the belt to both deflect in a torsional mode to follow changes in the contour of the cutting edge and to deflect in a bending mode to provide a desired radius of curvature to the formed cutting edge, both deflection modes are not necessarily required. That is, while both modes are preferably utilized together, each has separate utility and can be implemented without the other. For example and not by way of limitation, a given tool may be rotated as the tool is drawn back across the belt, thereby removing the advantageous torsional operation of the belt upon the cutting edge. Indeed, the sharpener could be readily configured to support the belt and prevent such torsion, as desired. Accordingly, the flow of FIG. 15 shows that torsion and/or bend modes of deflection are induced during presentation of the tool.
Preferably, the sharpening operation is applied to opposing sides of the tool, such as depicted in FIGS. 10A-10C , so FIG. 15 applies the foregoing step to the other side of the tool at step 308 . The operations at steps 306 and 308 can be carried out via the sharpening guides 112 , or can be carried out on the belt 116 with the guide housing removed, as depicted in FIGS. 2 and 13-14 .
A determination is made at decision step 310 as to whether additional sharpening operations are desired; if so, a new belt is installed onto the sharpener at step 312 and steps 304 through 310 are repeated using the new belt. Preferably, the new belt has a finer abrasiveness level (e.g., 1200 grit v. 400 grit, etc.) and less linear stiffness than then first belt. This sequence will generally result in the generation of a new cutting edge along the cutting tool, as depicted in FIGS. 10B-10C . Once all of the desired sharpening stages have been completed, the routine ends as shown at step 314 .
While step 312 sets forth the removal of an existing belt and the installation of a new replacement belt onto the sharpener 100 , it will be appreciated that such is not necessarily limiting to the scope of the claimed subject matter. Rather, the sharpener 100 can be readily adapted to concurrently operate multiple belts so that the tool is merely moved from one belt to another during the above sequence.
Any number of sharpener configurations can be employed as desired. As noted previously, the respective bending and twisting modes are dependent on a number of factors relating to the configuration, speed and tension force upon a given abrasive belt.
For purposes of reference, it has been found in preferred embodiments to utilize relatively narrow abrasive belts with lengths on the order of about 12 inches to 18 inches and widths of about 0.5 inches. The distance (journal length) between adjacent supports (e.g., such as the distance along the belt from rollers 118 , 122 in FIG. 3 ) can preferably vary from as low as around 2 inches to up to about 6 inches or more. The linear speed of the belt can also vary, with a preferred range being from about 1,500 feet/minute (ft/min) to about 5,000 ft/min. A preferred tension force supplied to the belt (such as via the tensioner spring 126 ) is on the order of around 4 pounds (lbs), with a preferred range of from about 0.5 lbs to upwards of about 10 lbs. It will be appreciated that the foregoing values and ranges merely serve to illustrate preferred embodiments and are not limiting.
It is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and function of various embodiments of the invention, this detailed description is illustrative only, and changes may be made in detail, especially in matters of structure and arrangements of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
|
Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.
| 1
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. application Ser. No. 11/978,066, filed Oct. 26, 2007; which is a divisional of U.S. application Ser. No. 10/939,630, filed Sep. 13, 2004, now U.S. Pat. No. 7,306,594; which is a divisional of U.S. application Ser. No. 09/845,022, filed Apr. 27, 2001, now U.S. Pat. No. 6,837,886; all of which are entitled APPARATUS AND METHODS FOR MAPPING AND ABLATION IN ELECTROPHYSIOLOGY PROCEDURES, all of which are hereby incorporated herein by reference in their entirety, and which, in turn, claim the benefit of U.S. Provisional Application Ser. No. 60/261,015 entitled HIGH DENSITY MAPPING AND ABLATION CATHETER AND METHOD OF USE, filed Jan. 11, 2001; U.S. Provisional Application Ser. No. 60/204,457 entitled METHOD FOR CREATING ANNULAR EPICARDIAL LESIONS AT THE OSTIA OF THE PULMONARY VEINS, filed on May 16, 2000; U.S. Provisional Application Ser. No. 60/204,482 entitled METHOD AND DEVICE FOR CREATING ANNULAR ENDOCARDIAL LESIONS AT THE OSTIA OF THE PULMONARY VEINS, filed May 16, 2000; and U.S. Provisional Application Ser. No. 60/201,445 entitled TRANSMURAL CIRCUMFERENTIAL LESIONS MADE AT CANINE PV OSTIUM BY EXPANDABLE MESH ELECTRODES IN VIVO, filed May 3, 2000, all of which are also hereby incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] The human heart is a very complex organ, which relies on both muscle contraction and electrical impulses to function properly. The electrical impulses travel through the heart walls, first through the atria and then the ventricles, causing the corresponding muscle tissue in the atria and ventricles to contract. Thus, the atria contract first, followed by the ventricles. This order is essential for proper functioning of the heart.
[0003] Over time, the electrical impulses traveling through the heart can begin to travel in improper directions, thereby causing the heart chambers to contract at improper times. Such a condition is generally termed a cardiac arrhythmia, and can take many different forms. When the chambers contract at improper times, the amount of blood pumped by the heart decreases, which can result in premature death of the person.
[0004] Techniques have been developed which are used to locate cardiac regions responsible for the cardiac arrhythmia, and also to disable the short-circuit function of these areas. According to these techniques, electrical energy is applied to a portion of the heart tissue to ablate that tissue and produce scars which interrupt the reentrant conduction pathways or terminate the focal initiation. The regions to be ablated are usually first determined by endocardial mapping techniques. Mapping typically involves percutaneously introducing a catheter having one or more electrodes into the patient, passing the catheter through a blood vessel (e.g. the femoral vein or artery) and into an endocardial site (e.g., the atrium or ventricle of the heart), and deliberately inducing an arrhythmia so that a continuous, simultaneous recording can be made with a multichannel recorder at each of several different endocardial positions. When an arrythormogenic focus or inappropriate circuit is located, as indicated in the electrocardiogram recording, it is marked by various imaging or localization means so that cardiac arrhythmias emanating from that region can be blocked by ablating tissue. An ablation catheter with one or more electrodes can then transmit electrical energy to the tissue adjacent the electrode to create a lesion in the tissue. One or more suitably positioned lesions will typically create a region of necrotic tissue which serves to disable the propagation of the errant impulse caused by the arrythromogenic focus. Ablation is carried out by applying energy to the catheter electrodes. The ablation energy can be, for example, RF, DC, ultrasound, microwave, or laser radiation.
[0005] Atrial fibrillation together with atrial flutter are the most common sustained arrhythmias found in clinical practice.
[0006] Current understanding is that atrial fibrillation is frequently initiated by a focal trigger from the orifice of or within one of the pulmonary veins. Though mapping and ablation of these triggers appears to be curative in patients with paroxysmal atrial fibrillation, there are a number of limitations to ablating focal triggers via mapping and ablating the earliest site of activation with a “point” radiofrequency lesion. One way to circumvent these limitations is to determine precisely the point of earliest activation. Once the point of earliest activation is identified, a lesion can be generated to electrically isolate the trigger with a lesion; firing from within those veins would then be eliminated or unable to reach the body of the atrium, and thus could not trigger atrial fibrillation.
[0007] Another method to treat focal arrhythmias is to create a continuous, annular lesion around the ostia (i.e., the openings) of either the veins or the arteries leading to or from the atria thus “corralling” the signals emanating from any points distal to the annular lesion. Conventional techniques include applying multiple point sources around the ostia in an effort to create such a continuous lesion. Such a technique is relatively involved, and requires significant skill and attention from the clinician performing the procedures.
[0008] Another source of arrhythmias may be from reentrant circuits in the myocardium itself. Such circuits may not necessarily be associated with vessel ostia, but may be interrupted by means of ablating tissue either within the circuit or circumscribing the region of the circuit. It should be noted that a complete ‘fence’ around a circuit or tissue region is not always required in order to block the propagation of the arrhythmia; in many cases simply increasing the propagation path length for a signal may be sufficient. Conventional means for establishing such lesion ‘fences’ include a multiplicity of point-by-point lesions, dragging a single electrode across tissue while delivering energy, or creating an enormous lesion intended to inactivate a substantive volume of myocardial tissue.
[0009] Commonly-owned U.S. patent application Ser. No. 09/396,502, entitled Apparatus For Creating A Continuous Annular Lesion, which is hereby incorporated by reference, discloses a medical device which is capable of ablating a continuous ring of tissue around the ostia of either veins or arteries leading to or from the atria.
SUMMARY OF THE INVENTION
[0010] The present invention encompasses apparatus and methods for mapping electrical activity within the heart. The present invention also encompasses methods and apparatus for creating lesions in the heart tissue (ablating) to create a region of necrotic tissue which serves to disable the propagation of errant electrical impulses caused by an arrhythmia.
[0011] In one embodiment, the present invention includes a medical device including a catheter having a braided conductive member at a distal end thereof, a mechanism for expanding the braided conductive member from an undeployed to a deployed position, and a mechanism for applying energy via the braided conductive member to blood vessel.
[0012] In one embodiment, the medical device further includes a mechanism for irrigating the braided conductive member.
[0013] In another embodiment, the medical device further includes at least one reference electrode disposed on a shaft of the catheter.
[0014] In another embodiment, the medical device includes a mechanism for controlling the energy supplied to the braided conductive member.
[0015] In another embodiment, the medical device further includes a mechanism for covering at least a portion of the braided conductive member when the braided conductive member is in the deployed position.
[0016] In another embodiment, at least a portion of the braided conductive member has a coating applied thereto.
[0017] In another embodiment, the medical device includes a mechanism for measuring temperature.
[0018] In another embodiment, the medical device includes a mechanism for steering the catheter.
[0019] The invention also includes a method for treating cardiac arrhythmia, including the steps of introducing a catheter having a braided conductive member at a distal end thereof into a blood vessel, expanding the braided conductive member at a selected location in the blood vessel so that the braided conductive member contacts a wall of the blood vessel, and applying energy to the wall of the blood vessel via the braided conductive member to create a lesion in the blood vessel.
[0020] In another embodiment, the invention includes a method for treating cardiac arrhythmia, including the steps of introducing a catheter into a thoracic cavity of a patient, the catheter having a braided conductive member at a distal end thereof, contacting an exterior wall of a blood vessel in a vicinity of an ostium with the braided conductive member, and applying energy to the blood vessel via the braided conductive member to create a lesion on the exterior wall of the blood vessel.
[0021] Another embodiment described herein relates to a method for treating a condition of a patient. The method comprises acts of introducing a portion of a catheter into a patient, the catheter having a braided conductive member at a distal end thereof, contacting an exterior wall of a blood vessel with the braided conductive member, and applying energy to the exterior wall via the braided conductive member to treat the condition.
[0022] A further embodiment described herein relates to a method comprising an act of introducing a portion of a catheter into a patient, the catheter having a braided conductive member at a distal end thereof. The braided conductive member comprises a plurality of filaments. The method also comprises acts of contacting a wall of a blood vessel with the braided conductive member and energizing at least some of the plurality of filaments to apply energy to the wall via the braided conductive member. The method further comprises acts of sensing, during the act of energizing, at least one temperature using at least one temperature sensor coupled to the braided conductive member; and controlling energy delivery to the braided conductive member based on the at least one sensed temperature.
[0023] The braided conductive member may be a wire mesh.
[0024] The features and advantages of the present invention will be more readily understood and apparent from the following detailed description of the invention, which should be read in conjunction with the accompanying drawings, and from the claims which are appended at the end of the Detailed Description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In the drawings, which are incorporated herein by reference and in which like elements have been given like references characters,
[0026] FIG. 1 illustrates an overview of a mapping and ablation catheter system in accordance with the present invention;
[0027] FIGS. 2 and 3 illustrate further details of the catheter illustrated in FIG. 1 ;
[0028] FIGS. 4-7 illustrate further details of the braided conductive member illustrated in FIGS. 2 and 3 ;
[0029] FIGS. 8-10A illustrate, among other things, temperature sensing in the present invention;
[0030] FIGS. 11-13 illustrate further details of the steering capabilities of the present invention;
[0031] FIGS. 14-17 illustrate further embodiments of the braided conductive member;
[0032] FIGS. 18-19 illustrate the use of irrigation in connection with the present invention;
[0033] FIGS. 20A-20E illustrate the use of shrouds in the present invention;
[0034] FIG. 21 illustrates a guiding sheath that may be used in connection with the present invention;
[0035] FIGS. 22-24 illustrate methods of using the present invention.
DETAILED DESCRIPTION
System Overview
[0036] Reference is now made to FIG. 1 , which figure illustrates an overview of a mapping and ablation catheter system in accordance with the present invention. The system includes a catheter 10 having a shaft portion 12 , a control handle 14 , and a connector portion 16 . A controller 8 is connected to connector portion 16 via cable 6 . Ablation energy generator 4 may be connected to controller 8 via cable 3 . A recording device 2 may be connected to controller 8 via cable 1 . When used in an ablation application, controller 8 is used to control ablation energy provided by ablation energy generator 4 to catheter 10 . When used in a mapping application, controller 8 is used to process signals coming from catheter 10 and to provide these signals to recording device 2 . Although illustrated as separate devices, recording device 2 , ablation energy generator 4 , and controller 8 could be incorporated into a single device. In one embodiment, controller 8 may be a QUADRAPULSE RF CONTROLLER™ device available from CR Bard, Inc., Murray Hill, N.J.
[0037] In this description, various aspects and features of the present invention will be described. The various features of the invention are discussed separately for clarity. One skilled in the art will appreciate that the features may be selectively combined in a device depending upon the particular application. Furthermore, any of the various features may be incorporated in a catheter and associated method of use for either mapping or ablation procedures.
Catheter Overview
[0038] Reference is now made to FIGS. 2-7 , which figures illustrate one embodiment of the present invention. The present invention generally includes a catheter and method of its use for mapping and ablation in electrophysiology procedures. Catheter 10 includes a shaft portion 12 , a control handle 14 , and a connector portion 16 . When used in mapping applications, connector portion 16 is used to allow signal wires running from the electrodes at the distal portion of the catheter to be connected to a device for processing the electrical signals, such as a recording device.
[0039] Catheter 10 may be a steerable device. FIG. 2 illustrates the distal tip portion 18 being deflected by the mechanism contained within control handle 14 . Control handle 14 may include a rotatable thumb wheel which can be used by a user to deflect the distal end of the catheter. The thumb wheel (or any other suitable actuating device) is connected to one or more pull wires which extend through shaft portion 12 and are connected to the distal end 18 of the catheter at an off-axis location, whereby tension applied to one or more of the pull wires causes the distal portion of the catheter to curve in a predetermined direction or directions. U.S. Pat. Nos. 5,383,852, 5,462,527, and 5,611,777, which are hereby incorporated by reference, illustrate various embodiments of control handle 14 that may be used for steering catheter 10 .
[0040] Shaft portion 12 includes a distal tip portion 18 , a first stop 20 and an inner member 22 connected to the first stop portion 20 . Inner member 22 may be a tubular member. Concentrically disposed about inner member 22 is a first sheath 24 and a second sheath 26 . Also concentrically disposed about inner member 22 is a braided conductive member 28 anchored at respective ends 30 and 32 to the first sheath 24 and the second sheath 26 , respectively.
[0041] In operation, advancing the second sheath 26 distally over inner member 22 causes the first sheath 24 to contact stop 20 . Further distal advancement of the second sheath 26 over inner member 22 causes the braided conductive member 28 to expand radially to assume various diameters and/or a conical shape. FIG. 3 illustrates braided conductive member 28 in an unexpanded (collapsed or “undeployed”) configuration. FIGS. 2 and 4 illustrate braided conductive member 28 in a partially expanded condition. FIG. 1 illustrates braided conductive member 28 radially expanded (“deployed”) to form a disk.
[0042] Alternatively, braided conductive member 28 can be radially expanded by moving inner member 22 proximally with respect to the second sheath 26 .
[0043] As another alternative, inner member 22 and distal tip portion 18 may be the same shaft and stop 20 may be removed. In this configuration, sheath 24 moves over the shaft in response to, for example, a mandrel inside shaft 22 and attached to sheath 24 in the manner described, for example, in U.S. Pat. No. 6,178,354, which is incorporated herein by reference.
[0044] As illustrated particularly in FIGS. 4 and 5 a third sheath 32 may be provided. The third sheath serves to protect shaft portion 12 and in particular braided conductive member 28 during manipulation through the patient's vasculature. In addition, the third sheath 32 shields braided conductive member 28 from the patient's tissue in the event ablation energy is prematurely delivered to the braided conductive member 28 .
[0045] The respective sheaths 24 , 26 , and 32 can be advanced and retracted over the inner member 22 , which may be a tubular member, in many different manners. Control handle 14 may be used. U.S. Pat. Nos. 5,383,852, 5,462,527, and 5,611,777 illustrate examples of control handles that can control sheaths 24 , 26 , and 32 . As described in these incorporated by reference patents, control handle 14 may include a slide actuator which is axially displaceable relative to the handle. The slide actuator may be connected to one of the sheaths, for example, the second sheath 26 to control the movement of the sheath 26 relative to inner member 22 , to drive braided conductive member 28 between respective collapsed and deployed positions, as previously described. Control handle 14 may also include a second slide actuator or other mechanism coupled to the retractable outer sheath 32 to selectively retract the sheath in a proximal direction with respect to the inner member 22 .
[0046] Braided conductive member 28 is, in one embodiment of the invention, a plurality of interlaced, electrically conductive filaments 34 . Braided conductive member 28 may be a wire mesh. The filaments are flexible and capable of being expanded radially outwardly from inner member 22 . The filaments 34 are preferably formed of metallic elements having relatively small cross sectional diameters, such that the filaments can be expanded radially outwardly. The filaments may be round, having a dimension on the order of about 0.001-0.030 inches in diameter. Alternatively, the filaments may be flat, having a thickness on the order of about 0.001-0.030 inches, and a width on the order of about 0.001-0.030 inches. The filaments may be formed of Nitinol type wire. Alternatively, the filaments may include non metallic elements woven with metallic elements, with the non metallic elements providing support to or separation of the metallic elements. A multiplicity of individual filaments 34 may be provided in braided conductive member 28 , for example up to 300 or more filaments.
[0047] Each of the filaments 34 can be electrically isolated from each other by an insulation coating. This insulation coating may be, for example, a polyamide type material. A portion of the insulation on the outer circumferential surface 60 of braided conductive member 28 is removed. This allows each of the filaments 34 to form an isolated electrode, not an electrical contact with any other filament, that may be used for mapping and ablation. Alternatively, specific filaments may be permitted to contact each other to form a preselected grouping.
[0048] Each of the filaments 34 is helically wound under compression about inner member 22 . As a result of this helical construction, upon radial expansion of braided conductive member 28 , the portions of filaments 34 that have had the insulation stripped away do not contact adjacent filaments and thus, each filament 34 remains electrically isolated from every other filament. FIG. 6 , in particular, illustrates how the insulation may be removed from individual filaments 34 while still providing isolation between and among the filaments. As illustrated in FIG. 6 , regions 50 illustrate regions, on the outer circumferential surface 60 of braided conductive member 28 , where the insulation has been removed from individual filaments 34 . In one embodiment of the invention, the insulation may be removed from up to one half of the outer facing circumference of each of the individual filaments 34 while still retaining electrical isolation between each of the filaments 34 .
[0049] The insulation on each of the filaments 34 that comprise braided conductive member 28 may be removed about the outer circumferential surface 60 of braided conductive member 28 in various ways. For example, one or more circumferential bands may be created along the length of braided conductive member 28 . Alternatively, individual sectors or quadrants only may have their insulation removed about the circumference of braided conductive member 28 . Alternatively, only selected filaments 34 within braided conductive member 28 may have their circumferentially facing insulation removed. Thus, an almost limitless number of configurations of insulation removal about the outer circumferential surface 60 of braided conductive member 28 can be provided depending upon the mapping and ablation characteristics and techniques that a clinician desires.
[0050] The insulation on each of the filaments 34 may be removed at the outer circumferential surface 60 of braided conductive member 28 in a variety of ways as long as the insulation is maintained between filaments 34 so that filaments 34 remain electrically isolated from each other.
[0051] The insulation can be removed from the filaments 34 in a variety of ways to create the stripped portions 50 on braided conductive member 28 . For example, mechanical means such as abration or scraping may be used. In addition, a water jet, chemical means, or thermal radiation means may be used to remove the insulation.
[0052] In one example of insulation removal, braided conductive member 28 may be rotated about inner member 22 , and a thermal radiation source such as a laser may be used to direct radiation at a particular point along the length of braided conductive member 28 . As the braided conductive member 28 is rotated and the thermal radiation source generates heat, the insulation is burned off the particular region.
[0053] Insulation removal may also be accomplished by masking selected portions of braided conductive member 28 . A mask, such as a metal tube may be placed over braided conducive member 28 . Alternatively, braided conductive member 28 may be wrapped in foil or covered with some type of photoresist. The mask is then removed in the areas in which insulation removal is desired by, for example, cutting away the mask, slicing the foil, or removing the photoresist. Alternatively, a mask can be provided that has a predetermined insulation removal pattern. For example, a metal tube having cutouts that, when the metal tube is placed over braided conductive member 28 , exposes areas where insulation is to be removed.
[0054] FIG. 6 illustrates how thermal radiation 52 may be applied to the outer circumferential surface 56 of a respective filament 34 that defines the outer circumferential surface 60 of braided conductive member 28 . As thermal radiation 52 is applied, the insulation 54 is burned off or removed from the outer circumference 56 of wire 34 to create a region 58 about the circumference 56 of filament 34 that has no insulation.
[0055] The insulation 54 can also be removed in a preferential manner so that a particular portion of the circumferential surface 56 of a filament 34 is exposed. Thus, when braided conductive member 28 is radially expanded, the stripped portions of filaments may preferentially face the intended direction of mapping or ablation.
[0056] With the insulation removed from the portions of filaments 34 on the outer circumferential surface 60 of braided conductive member 28 , a plurality of individual mapping and ablation channels can be created. A wire runs from each of the filaments 34 within catheter shaft 12 and control handle 14 to connector portion 16 . A multiplexer or switch box may be connected to the conductors so that each filament 34 may be controlled individually. This function may be incorporated into controller 8 . A number of filaments 34 may be grouped together for mapping and ablation. Alternatively, each individual filament 34 can be used as a separate mapping channel for mapping individual electrical activity within a blood vessel at a single point. Using a switch box or multiplexer to configure the signals being received by filaments 34 or ablation energy sent to filaments 34 results in an infinite number of possible combinations of filaments for detecting electrical activity during mapping procedures and for applying energy during an ablation procedure.
[0057] By controlling the amount of insulation that is removed from the filaments 34 that comprise braided conductive member 28 , the surface area of the braid that is in contact with a blood vessel wall can also be controlled. This in turn will allow control of the impedance presented to an ablation energy generator, for example, generator 4 . In addition, selectively removing the insulation can provide a predetermined or controllable profile of the ablation energy delivered to the tissue.
[0058] The above description illustrates how insulation may be removed from a filaments 34 . Alternatively, the same features and advantages can be achieved by adding insulation to filaments 34 . For example, filaments 34 may be bare wire and insulation can be added to them.
[0059] Individual control of the electrical signals received from filaments 34 allows catheter 10 to be used for bipolar (differential or between filament) type mapping as well as unipolar (one filament with respect to a reference) type mapping.
[0060] Catheter 10 may also have, as illustrated in FIGS. 2 and 3 , a reference electrode 13 mounted on shaft 12 so that reference electrode 13 is located outside the heart during unipolar mapping operations.
[0061] Radiopaque markers can also be provided for use in electrode orientation and identification.
[0062] One skilled in the art will appreciate all of the insulation can be removed from filaments 34 to create a large ablation electrode.
[0063] Although a complete catheter steerable structure has been illustrated, the invention can also be adapted so that inner tubular member 22 is a catheter shaft, guide wire, or a hollow tubular structure for introduction of saline, contrast media, heparin or other medicines, or introduction of guidewires, or the like.
Temperature Sensing
[0064] A temperature sensor or sensors, such as, but not limited to, one or more thermocouples may be attached to braided conductive member 28 for temperature sensing during ablation procedures. A plurality of thermocouples may also be woven into the braided conductive member 28 . An individual temperature sensor could be provided for each of the filaments 34 that comprise braided conductive member 28 . Alternatively, braided conductive member 28 can be constructed of one or more temperature sensors themselves.
[0065] FIG. 8 illustrates braided conductive member 28 in its fully expanded or deployed configuration. Braided conductive member 28 forms a disk when fully expanded. In the embodiment illustrated in FIG. 8 , there are sixteen filaments 34 that make up braided conductive member 28 .
[0066] Temperature monitoring or control can be incorporated into braided conductive member 28 , for example, by placing temperature sensors (such as thermocouples, thermistors, etc.) on the expanded braided conductive member 28 such that they are located on the distally facing ablative ring formed when braided conductive member 28 is in its fully expanded configuration. “Temperature monitoring” refers to temperature reporting and display for physician interaction. “Temperature control” refers to the capability of adding an algorithm in a feedback loop to titrate power based on temperature readings from the temperature sensors disposed on braided conductive member 28 . Temperature sensors can provide a means of temperature control provided the segment of the ablative ring associated with each sensor is independently controllable (e.g., electrically isolated from other regions of the mesh). For example, control can be achieved by dividing the ablative structure into electrically independent sectors, each with a temperature sensor, or alternatively, each with a mechanism to measure impedance in order to facilitate power titration. The ablative structure may be divided into electrically independent sectors so as to provide zone control. The provision of such sectors can be used to provide power control to various sections of braided conductive member 28 .
[0067] As illustrated in FIG. 8 , four temperature sensors 70 are provided on braided conductive member 28 . As noted previously, since the individual filaments 34 in braided conductive member 28 are insulated from each other, a number of independent sectors may be provided. A sector may include one or more filaments 34 . During ablation procedures, energy can be applied to one or more of the filaments 34 in any combination desired depending upon the goals of the ablation procedure. A temperature sensor could be provided on each filament 34 of braided conductive member 28 or shared among one or more filaments. In mapping applications, one or more of the filaments 34 can be grouped together for purposes of measuring electrical activity. These sectoring functions can be provided in controller 8 .
[0068] FIG. 10 illustrates a side view of braided conductive member 28 including temperature sensors 70 . As shown in FIG. 10 , temperature sensors 70 emerge from four holes 72 . Each hole 72 is disposed in one quadrant of anchor 74 . The temperature sensors 70 are bonded to the outside edge 76 of braided conductive member 28 . Temperature sensors 70 may be isolated by a small piece of polyimide tubing 73 around them and then bonded in place to the filaments. The temperature sensors 7 may be woven and twisted into braided conductive member 28 or they can be bonded on a side-by-side or parallel manner with the filaments 34 .
[0069] There are several methods of implementing electrically independent sectors. In one embodiment, the wires are preferably stripped of their insulative coating in the region forming the ablative ring (when expanded). However, sufficient insulation may be left on the wires in order to prevent interconnection when in the expanded state. Alternatively, adjacent mesh wires can be permitted to touch in their stripped region, but can be separated into groups by fully insulated (unstripped) wires imposed, for example, every 3 or 5 wires apart (the number of wires does not limit this invention), thus forming sectors of independently controllable zones. Each zone can have its own temperature sensor. The wires can be “bundled” (or independently attached) to independent outputs of an ablation energy generator. RF energy can then be titrated in its application to each zone by switching power on and off (and applying power to other zones during the ‘off period’) or by modulating voltage or current to the zone (in the case of independent controllers). In either case, the temperature inputs from the temperature sensors can be used in a standard feedback algorithm to control the power delivery.
[0070] Alternatively, as illustrated in FIG. 10A , braided conductive member 28 may be used to support a ribbon-like structure which is separated into discrete sectors. As shown in FIG. 10A , the ribbon-like structure 81 may be, for example, a pleated copper flat wire that, as braided conductive member 28 expands, unfolds into an annular ring. Each of the wires 83 a - 83 d lie in the same plane. Although four wires are illustrated in FIG. 10A , structure 81 may include any number of wires depending upon the application and desired performance. Each of wires 83 a - 83 d is insulated. Insulation may then be removed from each wire to create different sectors 85 a - 85 d. Alternatively, each of wires 83 a - 83 d may be uninsulated and insulation may be added to create different sectors. The different sectors provide an ablative zone comprised of independently controllable wires 83 a - 83 d. Temperature sensors 70 may be mounted on the individual wires, and filaments 34 may be connected to respective wires 83 a - 83 d to provide independent control of energy to each individual sector. One skilled in the art will appreciate that each of wires 83 a - 83 d can have multiple sectors formed by removing insulation in various locations and that numerous combinations of sectors 85 a - 85 d and wires 83 a - 83 d forming ribbon-like structure 81 can be obtained.
Steering
[0071] Reference is now made to FIGS. 11-13 which illustrate aspects of the steering capabilities of the present invention. As illustrated in FIGS. 1-2 , catheter 10 is capable of being steered using control handle 14 . In particular, FIG. 1 illustrates steering where the steering pivot or knuckle is disposed on catheter shaft 12 in a region that is distal to the braided conductive member 28 .
[0072] FIG. 11 illustrates catheter 10 wherein the pivot point or steering knuckle is disposed proximal to braided conductive member 28 .
[0073] FIG. 12 illustrates catheter 10 having the capability of providing steering knuckles both proximal and distal to braided conductive member 28 .
[0074] FIGS. 1-2 , and 11 - 12 illustrate two dimensional or single plane type steering. The catheter of the present invention can also be used in connection with a three dimensional steering mechanism. For example, using the control handle in the incorporated by reference '852 patent, the catheter can be manipulated into a three-dimensional “lasso-like” shape, particularly at the distal end of the catheter. As shown in FIG. 13 , the catheter can have a primary curve 80 in one plane and then a second curve 82 in another plane at an angle to the first plane. With this configuration, the catheter can provide increased access to difficult to reach anatomical structures. For example, a target site for a mapping or ablation operation may be internal to a blood vessel. Thus, the increased steering capability can allow easier access into the target blood vessel. In addition, the additional dimension of steering can allow for better placement of braided conductive member 28 during an ablation or mapping procedure. Catheter 10 can be inserted into a site using the steering capabilities provided by primary curve 80 . Thereafter, using the secondary curve 82 , braided conductive member 28 can be tilted into another plane for better orientation or contact with the target site.
Conductive Member Configurations and Materials
[0075] Reference is now made to FIGS. 14-17 which figures illustrate other configurations of braided conductive member 28 . As has been described above and will be described in more detail, braided conductive member 28 can include from one to 300 or more filaments. The filaments may vary from very fine wires having small diameters or cross-sectional areas to large wires having relatively large diameters or cross-sectional areas.
[0076] FIG. 14 illustrates the use of more than one braided conductive member 28 as the distal end of catheter 10 . As shown in FIG. 14 , three braided conductive members 28 A, 28 B, and 28 C are provided at the distal end of catheter 10 . Braided conductive members 28 A, 28 B, and 29 C may be, in their expanded conditions, the same size or different sizes. Each of the braided conductive members 28 A, 28 B, and 28 C can be expanded or contracted independently in the manner illustrated in FIGS. 1-4 via independent control shafts 26 A, 26 B, and 26 C. The use of multiple braided conductive members provides several advantages. Rather than having to estimate or guess as to the size of the blood vessel prior to starting a mapping or ablation procedure, if braided conductive members 28 A, 28 B, and 28 C are of different expanded diameters, than sizing can be done in vivo during a procedure. In addition, one of the braided conductive members can be used for ablation and another of the braided conductive members can be used for mapping. This allows for quickly checking the effectiveness of an ablation procedure.
[0077] Reference is now made to FIGS. 15A and 15B , which figures illustrate other shapes of braided conductive member 28 . As described up to this point, braided conductive member 28 is generally symmetrical and coaxial with respect to catheter shaft 12 . However, certain anatomical structures may have complex three-dimensional shapes that are not easily approximated by a geometrically symmetrical mapping or ablation structure. One example of this type of structure occurs at the CS ostium. To successfully contact these types of anatomical structures, braided conductive member 28 can be “preformed” to a close approximation of that anatomy, and yet still be flexible enough to adapt to variations found in specific patients. Alternatively, braided conductive member 28 can be “preformed” to a close approximation of that anatomy, and be of sufficient strength (as by choice of materials, configuration, etc.) to force the tissue to conform to variations found in specific patients. For example FIG. 15A illustrates braided conductive member 28 disposed about shaft 12 in an off-center or non concentric manner. In addition, braided conductive member 28 may also be constructed so that the parameter of the braided conductive member in its expanded configuration has a non-circular edge so as to improve tissue contact around the parameter of the braided conductive member. FIG. 15B illustrates an example of this type of configuration where the braided conductive member 28 is both off center or non concentric with respect to catheter shaft 12 and also, in its deployed or expanded configuration, has an asymmetric shape. The eccentricity of braided conductive member 28 with respect to the shaft and the asymmetric deployed configurations can be produced by providing additional structural supports in braided conductive member 28 , for example, such as by adding nitinol, ribbon wire, and so on. In addition, varying the winding pitch or individual filament size or placement or deforming selective filaments in braided conductive member 28 or any other means known to those skilled in the art may be used.
[0078] FIGS. 16A-16C illustrate another configuration of braided conductive member 28 and catheter 10 . As illustrated in FIGS. 16A-16C , the distal tip section of catheter 10 has been removed and braided conductive member 28 is disposed at the distal end of catheter 10 . One end of braided conductive member 28 is anchored to catheter shaft 12 using an anchor band 90 that clamps the end 32 of braided conductive member 28 to catheter shaft 12 . The other end of braided conductive member 28 is clamped to an activating shaft such as shaft 22 using another anchor band 92 . FIG. 16A illustrates braided conductive member 28 in its undeployed configuration. As shaft 22 is moved distally, braided conductive member 28 emerges or everts from shaft 12 . As shown in FIG. 16B , braided conductive member 28 has reached its fully deployed diameter and an annular tissue contact zone 29 can be placed against an ostium or other anatomical structure. As illustrated in FIG. 16C , further distal movement of shaft 22 can be used to create a concentric locating region 94 that can help to provide for concentric placement within an ostium of a pulmonary vein, for example. Concentric locating region 94 may be formed by selective variations in the winding density of filaments 34 in braided conductive member 28 , preferential predeformation of the filaments, additional eversion of braided conductive member 28 from shaft 12 , or by other means known to those skilled in the art.
[0079] Reference is now made to FIG. 17 , which figure illustrates a further embodiment of braided conductive member 28 . As illustrated in FIG. 17 , braided conductive member 28 is composed of one or several large wires 96 rather than a multiplicity of smaller diameter wires. The wire or wires can be moved between the expanded and unexpanded positions in the same manner as illustrated in FIG. 1 . In addition, a region 98 may be provided in which the insulation has been removed for mapping or ablation procedures. The single wire or “corkscrew” configuration provides several advantages. First, the wire or wires do not cross each other and therefore there is only a single winding direction required for manufacture. In addition, the risk of thrombogenicity may be reduced because there is a smaller area of the blood vessel being blocked. In addition, the connections between the ends of the large wire and the control shafts may be simplified.
[0080] The catheter 10 of the present invention can be coated with a number of coatings that can enhance the operating properties of braided conductive member 28 . The coatings can be applied by any of a number of techniques and the coatings may include a wide range of polymers and other materials.
[0081] Braided conductive member 28 can be coated to reduce its coefficient of friction, thus reducing the possibility of thrombi adhesion to the braided conductive member as well as the possibility of vascular or atrial damage. These coatings can be combined with the insulation on the filaments that make up braided conductive member 28 , these coatings can be included in the insulation itself, or the coatings can be applied on top of the insulation. Examples of coating materials that can be used to improve the lubricity of the catheter include PD slick available from Phelps Dodge Corporation, Ag, Tin, BN. These materials can be applied by an ion beam assisted deposition (“IBAD”) technique developed by, for example, Amp Corporation.
[0082] Braided conductive member 28 can also be coated to increase or decrease its thermal conduction which can improve the safety or efficacy of the braided conductive member 28 . This may be achieved by incorporating thermally conductive elements into the electrical insulation of the filaments that make up braided conductive member 28 or as an added coating to the assembly. Alternatively, thermally insulating elements may be incorporated into the electrical insulation of the filaments that make up braided conductive member 28 or added as a coating to the assembly. Polymer mixing, IBAD, or similar technology could be used to add Ag, Pt, Pd, Au, Ir, Cobalt, and others into the insulation or to coat braided conductive member 28 .
[0083] Radioopaque coatings or markers can also be used to provide a reference point for orientation of braided conductive member 28 when viewed during fluoroscopic imaging. The materials that provide radiopacity including, for example, Au, Pt, Ir, and other known to those skilled in the art. These materials may be incorporated and used as coatings as described above.
[0084] Antithrombogenic coatings, such as heparin and BH, can also be applied to braided conductive member 28 to reduce thrombogenicity to prevent blood aggregation on braided conductive member 28 . These coatings can be applied by dipping or spraying, for example.
[0085] As noted above, the filament 34 of braided conductive member 28 may be constructed of metal wire materials. These materials may be, for example, MP35N, nitinol, or stainless steel. Filaments 34 may also be composites of these materials in combination with a core of another material such as silver or platinum. The combination of a highly conductive electrical core material with another material forming the shell of the wire allows the mechanical properties of the shell material to be combined with the electrical conductivity of the core material to achieve better and/or selectable performance. The choice and percentage of core material used in combination with the choice and percentage of shell material used can be selected based on the desired performance characteristics and mechanical/electrical properties desired for a particular application.
Irrigation
[0086] It is known that for a given electrode side and tissue contact area, the size of a lesion created by radiofrequency (RF) energy is a function of the RF power level and the exposure time. At higher powers, however, the exposure time can be limited by an increase in impedance that occurs when the temperature at the electrode-tissue interface approaches a 100° C. One way of maintaining the temperature less than or equal to this limit is to irrigate the ablation electrode with saline to provide convective cooling so as to control the electrode-tissue interface temperature and thereby prevent an increase in impedance. Accordingly, irrigation of braided conductive member 28 and the tissue site at which a lesion is to be created can be provided in the present invention. FIG. 18 illustrates the use of an irrigation manifold within braided conductive member 28 . An irrigation manifold 100 is disposed along shaft 22 inside braided conductive member 28 . Irrigation manifold 100 may be one or more polyimid tubes. Within braided conductive member 28 , the irrigation manifold splits into a number of smaller tubes 102 that are woven into braided conductive member 28 along a respective filament 34 . A series of holes 104 may be provided in each of the tubes 102 . These holes can be oriented in any number of ways to target a specific site or portion of braided conductive member 28 for irrigation. Irrigation manifold 100 runs through catheter shaft 12 and may be connected to an irrigation delivery device outside the patient used to inject an irrigation fluid, such as saline, for example, such as during an ablation procedure.
[0087] The irrigation system can also be used to deliver a contrast fluid for verifying location or changes in vessel diameter. For example, a contrast medium may be perfused prior to ablation and then after an ablation procedure to verify that there have been no changes in the blood vessel diameter. The contrast medium can also be used during mapping procedures to verify placement of braided conductive member 28 . In either ablation or mapping procedures, antithrombogenic fluids, such as heparin can also be perfused to reduce thrombogenicity.
[0088] FIG. 19 illustrates another way of providing perfusion/irrigation in catheter 10 . As illustrated in FIG. 19 , the filaments 34 that comprise braided conductive member 28 are composed of a composite wire 110 . The composite wire 110 includes an electrically conductive wire 112 that is used for delivering ablation energy in an ablation procedure or for detecting electrical activity during a mapping procedure. Electrical wire 112 is contained within a lumen 114 that also contains a perfusion lumen 116 . Perfusion lumen 116 is used to deliver irrigation fluid or a contrast fluid as described in connection with FIG. 18 . Once braided conductive member 28 has been constructed with composite wire 110 , the insulation 118 surrounding wire filament 112 can be stripped away to form an electrode surface. Holes can then be provided into perfusion lumen 116 to then allow perfusion at targeted sites along the electrode surface. As with the embodiment illustrated in FIG. 18 , the perfusion lumens can be connected together to form a manifold which manifold can then be connected to, for example, perfusion tube 120 and connected to a fluid delivery device.
Shrouds
[0089] The use of a shroud or shrouds to cover at least a portion of braided conductive member 28 can be beneficial in several ways. The shroud can add protection to braided conductive member 28 during insertion and removal of catheter 10 . A shroud can also be used to form or shape braided conductive member 28 when in its deployed state. Shrouds may also reduce the risk of thrombi formation on braided conductive member 28 by reducing the area of filament and the number of filament crossings exposed to blood contact. This can be particularly beneficial at the ends 30 and 32 of braided conductive member 28 . The density of filaments at ends 30 and 32 is greatest and the ends can therefore be prone to blood aggregation. The shrouds can be composed of latex balloon material or any material that would be resistant to thrombi formation durable enough to survive insertion through an introducer system, and would not reduce the mobility of braided conductive member 28 . The shrouds can also be composed of an RF transparent material that would allow RF energy to pass through the shroud. If an RF transparent material is used, complete encapsulation of braided conductive member 28 is possible.
[0090] A shroud or shrouds may also be useful when irrigation or perfusion is used, since the shrouds can act to direct irrigation or contrast fluid to a target region.
[0091] FIGS. 20A-20E illustrate various examples of shrouds that may be used in the present invention. FIG. 20A illustrates shrouds 130 and 132 disposed over end regions 31 and 33 , respectively, of braided conductive member 28 . This configuration can be useful in preventing coagulation of blood at the ends of braided conductive member 28 . FIG. 20B illustrates shrouds 130 and 132 used in conjunction with an internal shroud 134 contained inside braided conductive member 28 . In addition to preventing blood coagulation in regions 31 and 32 , the embodiment illustrated in FIG. 20B also prevents blood from entering braided conductive member 28 .
[0092] FIG. 20C illustrates shrouds 130 and 132 being used to direct and irrigation fluid or contrast medium along the circumferential edge of braided conductive member 28 . In the embodiment illustrated in FIG. 20C , perfusion can be provided as illustrated in FIGS. 18 and 19 .
[0093] FIG. 20D illustrates the use of an external shroud that covers braided conductive member 28 . Shroud 136 completely encases braided conductive member 28 and thereby eliminates blood contact with braided conductive member 28 . Shroud 136 may be constructed of a flexible yet ablation-energy transparent material so that, when used in an ablation procedure, braided conductive member 28 can still deliver energy to a targeted ablation site.
[0094] FIG. 20E also illustrates an external shroud 137 encasing braided conductive member 28 . Shroud 137 may also be constructed of a flexible yet ablation-energy transparent material. Openings 139 may be provided in shroud 137 to allow the portions of braided conductive member 28 that are exposed by the opening to come into contact with tissue. Openings 139 may be elliptical, circular, circumferential, etc.
Guiding Sheaths
[0095] There may be times during ablation or mapping procedures when catheter 10 is passing through difficult or tortuous vasculature. During these times, it may be helpful to have a guiding sheath through which to pass catheter 10 so as to allow easier passage through the patient's vasculature.
[0096] FIG. 21 illustrates one example of a guiding sheath that may be used in connection with catheter 10 . As illustrated in FIG. 21 , the guiding sheath 140 includes a longitudinal member 142 . Longitudinal member 142 may be constructed of a material rigid enough to be pushed next to catheter shaft 12 as the catheter is threaded through the vasiculature. In one example, longitudinal member 142 may be stainless steel. Longitudinal member 142 is attached to a sheath 144 disposed at the distal end 146 of longitudinal member 142 . The split sheath 144 may have one or more predetermined curves 148 that are compatible with the shapes of particular blood vessels (arteries or veins) that catheter 10 needs to pass through. Split sheath 144 may extend proximally along longitudinal member 142 . For example, sheath 144 and longitudinal member 142 may be bonded together for a length of up to 20 or 30 centimeters to allow easier passage through the patient's blood vessels. Sheath 144 includes a predetermined region 150 that extends longitudinally along sheath 144 . Region 150 may be, for example, a seam, that allows sheath 144 to be split open so that the guiding sheath 140 can be pulled back and peeled off catheter shaft 12 in order to remove the sheath.
[0097] In another embodiment, longitudinal member 142 may be a hypotube or the like having an opening 152 at distal end 146 that communicates with the interior of sheath 144 . In this embodiment, longitudinal member 142 can be used to inject irrigation fluid such as saline or a contrast medium for purposes of cooling, flushing, or visualization.
Methods of Use
[0098] Reference is now made to FIGS. 22 , 23 , and 24 , which figures illustrate how the catheter of the present invention may be used in endocardial and epicardial applications.
[0099] Referring to FIG. 22 , this figure illustrates an endocardial ablation procedure. In this procedure, catheter shaft 12 is introduced into a patient's heart 150 . Appropriate imaging guidance (direct visual assessment, camera port, fluoroscopy, echocardiographic, magnetic resonance, etc.) can be used. FIG. 22 in particular illustrates catheter shaft 12 being placed in the left atrium of the patient's heart. Once catheter shaft 12 reaches the patient's left atrium, it may then be introduced through an ostium 152 of a pulmonary vein 154 . As illustrated, braided conductive member 28 is then expanded to its deployed position, where, in the illustrated embodiment, braided conductive member 28 forms a disk. Catheter shaft 12 then advanced further into pulmonary vein 154 until the distal side 156 of braided conductive member 28 makes contact with the ostium of pulmonary vein 154 . External pressure may be applied along catheter shaft 12 to achieve the desired level of contact of braided conductive member 28 with the ostium tissue. Energy is then applied to the ostium tissue 152 in contact with braided conductive member 28 to create an annular lesion at or near the ostium. The energy used may be RF (radiofrequency), DC, microwave, ultrasonic, cryothermal, optical, etc.
[0100] Reference is now made to FIG. 23 , which figure illustrates an epicardial ablation procedure. As illustrated in FIG. 23 , catheter shaft 12 is introduced into a patient's thoracic cavity and directed to pulmonary vein 154 . Catheter 10 may be introduced through a trocar port or intraoperatively during open chest surgery Using a steering mechanism, preformed shape, or other means by which to make contact between braided conductive member 128 and the outer surface 158 of pulmonary vein 154 , braided conductive member 28 is brought into contact with the outer surface 158 of pulmonary vein 154 . Appropriate imaging guidance (direct visual assessment, camera port, fluoroscopy, echocardiographic, magnetic resonance, etc.) can be used. As illustrated in FIG. 23 , in this procedure, braided conductive member 28 remains in its undeployed or unexpanded condition. External pressure may be applied to achieve contact between braided conductive member 28 with pulmonary vein 154 . Once the desired contact with the outer surface 158 of pulmonary vein 154 is attained, ablation energy is applied to surface 158 via braided conductive member 28 using, for example, RF, DC, ultrasound, microwave, cryothermal, or optical energy. Thereafter, braided conductive member 28 may be moved around the circumference of pulmonary vein 154 , and the ablation procedure repeated. This procedure may be used to create, for example, an annular lesion at or near the ostium.
[0101] Use of the illustrated endocardial or epicardial procedures may be easier and faster than using a single “point” electrode since a complete annular lesion may be created in one application of RF energy.
[0102] Reference is now made to FIG. 24 which figure illustrates an endocardial mapping procedure. In the procedure illustrated in FIG. 24 , catheter shaft 12 is introduced into pulmonary vein 154 in the manner described in connection with FIG. 22 . Once braided conductive 28 has reached a desired location within pulmonary vein 154 , braided conductive member 28 is expanded as described in connection with, for example, FIGS. 2-5 until filaments 34 contact the inner wall 160 of pulmonary vein 154 . Thereafter, electrical activity within pulmonary vein 154 may be detected, measured, and recorded by an external device connected to the filaments 34 of braided conductive member 28 .
[0103] Access to the patient's heart can be accomplished via percutaneous, vascular, surgical (e.g. open-chest surgery), or transthoracic approaches for either endocardial or epicardial mapping and/or mapping and ablation procedures.
[0104] The present invention is thus able to provide an electrophysiology catheter capable of mapping and/or mapping and ablation operations. In addition, the catheter of the invention may be used to provide high density maps of a tissue region because electrocardiograms may be obtained from individual filaments 34 in braided conductive member 28 in either a bipolar or unipolar mode.
[0105] Furthermore, the shape of the electrode region can be adjusted by controlling the radial expansion of braided conductive member 28 so as to improve conformity with the patient's tissue or to provide a desired mapping or ablation profile. Alternatively, braided conductive member 28 may be fabricated of a material of sufficient flexural strength so that the tissue is preferentially conformed to match the expanded or partially expanded shape of the braided conductive member 28 .
[0106] The catheter of the present invention may be used for mapping procedures, ablation procedures, and temperature measurement and control on the distal and/or proximal facing sides of braided conductive member 28 in its fully expanded positions as illustrated in, for example, FIG. 1 . In addition, the catheter of the present invention can be used to perform “radial” mapping procedures, ablation procedures, and temperature measurement and control. That is, the outer circumferential edge 76 , illustrated, for example, in FIG. 8 , can be applied against an inner circumferential surface of a blood vessel.
[0107] Furthermore, being able to use the same catheter for both mapping and ablation procedures has the potential to reduce procedure time and reduce X-ray exposure.
[0108] The ability to expand braided conductive member 28 in an artery or vein against a tissue structure such as a freewall or ostium can provide good contact pressure for multiple electrodes and can provide an anatomical anchor for stability. Temperature sensors can be positioned definitively against the endocardium to provide good thermal conduction to the tissue. Lesions can be selectively produced at various sections around the circumference of braided conductive member 28 without having to reposition catheter 10 . This can provide more accurate lesion placement within the artery or vein.
[0109] Braided conductive member 28 , in its radially expanded position as illustrated in particular in FIGS. 1 and 8 is advantageous because, in these embodiments, it does not block the blood vessel during a mapping or ablation procedure, but allows blood flow through the braided conductive member thus allowing for longer mapping and/or ablation times, which can potentially improve accuracy of mapping and efficacy of lesion creation.
[0110] Having thus described at least one illustrative embodiment of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention is limited only as defined in the following claims and the equivalents thereto.
|
Embodiments described herein relate to methods of using a catheter having a braided conductive member. One embodiment relates to a method for treating a condition of a patient that involves contacting an exterior wall of a blood vessel with the braided conductive member. Another embodiment relates to a method that involves contacting a wall of a blood vessel with the braided conductive member and controlling energy delivery to the braided conductive member based on at least one sensed temperature.
| 0
|
COPYRIGHT NOTICE
[0001] A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction of the patent document or the patent disclosure, as it appears in the United States Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to systems and methods for inserting a description of images into audio recordings.
[0004] 2. Related Art
[0005] Recording a lecture or a presentation in an audio format can be a convenient and effective way to disseminate information beyond the immediate audience. However, if the presentation contains images, diagrams and charts, the lack of visual content can have a significant impact on the effectiveness of the delivery.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a system and method for inserting a description of images into audio recordings.
[0007] A method in accordance with an embodiment of the present invention begins by interpreting images through deciphering non-text content, compiling any meta-tag information, collecting optical character recognition (OCR) data, and/or the like. The method then integrates, filters, and prioritizes the information to create a useful and succinct non-visual (e.g., audio, text, etc.) description of the image. The results of this image interpretation and description augment the non-visual content when the images are not available, such as when listening to an audio recording, or hearing a text-to-speech system read the text. For example, the system can interpret common presentation and graphics programs and insert a description of the images in an audio recording of the presentation.
[0008] In an aspect, there is provided a method of inserting a description of an image into an audio recording, comprising: interpreting an image and producing a word description of the image including at least one image keyword; parsing an audio recording into a plurality of audio clips and producing a transcription of each audio clip, each audio clip transcription including at least one audio keyword; calculating a similarity distance between the at least one image keyword and the at least one audio keyword of each audio clip; and selecting the audio clip transcription having a shortest similarity distance to the at least one image keyword as a location to insert the word description of the image.
[0009] In an embodiment, the method further comprises appending the word description of the image to the selected audio clip to produce an augmented audio recording including at least one interpreted word description of an image.
[0010] In another embodiment, the method further comprises providing at least one template to interpret the image, the at least one template including at least one image interpretation component to produce a word description of the image.
[0011] In another embodiment, the method further comprises providing at least one of optical character recognition (OCR) technology, edge finding technology, color edge finding technology, curve finding technology, shape finding technology, and contrast finding technology as an image interpretation component in the at least one template.
[0012] In another embodiment, the method further comprises parsing the audio recording into a plurality of audio clips of substantially the same length, and adjusting the length of each audio clip to end at a natural pause in speech.
[0013] In another embodiment, the method further comprises calculating the similarity distance between the image and an audio clip by calculating the similarity distance between at least one image keyword of an image and the at least one audio keyword of an audio clip.
[0014] In another embodiment, the method further comprises obtaining the similarity distance between the at least one image keyword and the at least one audio keyword by calculating a path length between these keywords in a hierarchical semantic electronic dictionary.
[0015] In another aspect, there is provided a system for inserting a description of an image into an audio recording, comprising: an interpreting system for interpreting an image and producing a word description of the image including at least one image keyword; a parsing system for parsing an audio recording into a plurality of audio clips and for producing a transcription of each audio clip, each audio clip transcription including at least one audio keyword; a calculating system for calculating a similarity distance between the at least one image keyword and the at least one audio keyword of each audio clip; and a selecting system for selecting the audio clip transcription having a shortest similarity distance to the at least one image keyword as a location to insert the word description of the image.
[0016] In an embodiment, the system further comprises an appending system for appending the word description of the image to the selected audio clip to produce an augmented audio recording including at least one interpreted word description of an image.
[0017] In another embodiment, the system further comprises at least one template to interpret the image, the at least one template including at least one image interpretation component to produce a word description of the image.
[0018] In another embodiment, the system further comprises at least one of optical character recognition (OCR) technology, edge finding technology, color edge finding technology, curve finding technology, shape finding technology, and contrast finding technology as an image interpretation component in the at least one template.
[0019] In another embodiment, the system is configured to parse the audio recording into a plurality of audio clips of substantially the same length and adjust the length of each audio clip to end at a natural pause in speech.
[0020] In another embodiment, the system is configured to calculate the similarity distance between the image and an audio clip by calculating the similarity distance between at least one image keyword of an image and the at least one audio keyword of an audio clip.
[0021] In another embodiment, the system is configured to calculate the similarity distance between the at least one image keyword and the at least one audio keyword based a path length between these keywords in a hierarchical semantic electronic dictionary.
[0022] In another aspect, there is provided a program product stored on a computer readable medium, which when executed, inserts a description of an image into an audio recording, the computer readable medium comprising program code for: interpreting an image and producing a word description of the image including at least one image keyword; parsing an audio recording into a plurality of audio clips and producing a transcription of each audio clip, each audio clip transcription including at least one audio keyword; calculating a similarity distance between the at least one image keyword and the at least one audio keyword of each audio clip; and selecting the audio clip transcription having a shortest similarity distance to the at least one image keyword as a location to insert the word description of the image.
[0023] In an embodiment, the program product further comprises program code for appending the word description of the image to the selected audio clip to produce an augmented audio recording including at least one interpreted word description of an image.
[0024] In an embodiment, the program product further comprises program code for providing at least one template to interpret the image, the at least one template including at least one image interpretation component to produce a word description of the image.
[0025] In an embodiment, the program product further comprises program code for providing at least one of optical character recognition (OCR) technology, edge finding technology, color edge finding technology, curve finding technology, shape finding technology, and contrast finding technology as an image interpretation component in the at least one template.
[0026] In an embodiment, the program product further comprises program code for parsing the audio recording into a plurality of audio clips of substantially the same length, and adjusting the length of each audio clip to end at a natural pause in speech.
[0027] In an embodiment, the program product further comprises program code for calculating the similarity distance between the image and an audio clip by calculating the similarity distance between at least one image keyword of an image and the at least one audio keyword of an audio clip.
[0028] In an embodiment, the program product further comprises program code for obtaining the similarity distance between the at least one image keyword and the at least one audio keyword by calculating a path length between these keywords in a hierarchical semantic electronic dictionary.
[0029] These and other aspects of the invention will become apparent from the following more particular descriptions of exemplary embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] These and other features of the present invention will be more readily understood from the following detailed description taken in conjunction with the accompanying drawings.
[0031] FIG. 1 is a schematic diagram of a generic data processing system that can provide an operative environment for the present invention.
[0032] FIG. 2 shows a schematic flowchart of an illustrative image interpretation method in accordance with an embodiment of the present invention.
[0033] FIGS. 3A and 3B show a schematic flowchart of an illustrative source determining and pre-processing method in accordance with an embodiment of the present invention.
[0034] FIG. 4 shows an illustrative image file processing method in accordance with an embodiment of the present invention.
[0035] FIGS. 5A and 5B show a schematic flowchart of an illustrative component assembly method in accordance with an embodiment of the present invention.
[0036] FIG. 6 shows a schematic flowchart of an illustrative sound recording pre-processing method in accordance with an embodiment of the present invention.
[0037] FIG. 7 shows a schematic flowchart of an illustrative image insertion location search method in accordance with an embodiment of the present invention.
[0038] FIG. 8 shows a schematic flowchart of an illustrative image insertion method in accordance with an embodiment of the present invention.
[0039] FIG. 9 shows an illustrative example of an image that can be identified and described in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0040] As noted above, the present invention relates to a system and method for interpreting and describing graphic images.
[0041] The invention can be practiced in various embodiments. A suitably configured data processing system, and associated communications networks, devices, software, and firmware can provide a platform for enabling one or more of these systems and methods. By way of example, FIG. 1 shows a generic data processing system 100 that can include a central processing unit (“CPU”) 102 connected to a storage unit 104 and to a random access memory 106 . The CPU 102 can process an operating system 101 , application program 103 , and data 123 . The operating system 101 , application program 103 , and data 123 can be stored in storage unit 104 and loaded into memory 106 , as can be required. An operator 107 can interact with the data processing system 100 using a video display 108 connected by a video interface 105 , and various input/output devices such as a keyboard 110 , mouse 112 , and disk drive 114 connected by an I/O interface 109 . In known manner, the mouse 112 can be configured to control movement of a cursor in the video display 108 , and to operate various graphical user interface (“GUI”) controls appearing in the video display 108 with a mouse button. The disk drive 114 can be configured to accept data processing system readable media 116 . The data processing system 100 can form part of a network via a network interface 111 , allowing the data processing system 100 to communicate with other suitably configured data processing systems (not shown). The particular configurations shown by way of example in this specification are not meant to be limiting.
[0042] More generally, a method in accordance with an embodiment can involve interpreting and describing an image, and synchronizing the audio or text description with the logical insertion point in the audio or text transcript.
[0043] In interpreting the charts or diagrams, image pattern recognition technology can be used to identify the contents. Image processing technology can be used to extract text such as titles and notes. Meta-tagging technology can be used by the author, or by a contributor, and these tags can be used to augment and standardize the translation. Meta-tagging examples can include, for example, identifying the X and Y-axes, the chart type, segments of a chart, the legend, etc. Filtering technology can also be used to eliminate some data (such as page numbers, headers & footers) and highlight other information such as the chart title. As well, OCR technology can be used to determine other textual content. This OCR information can capture not only the text content, but also the position, orientation, text size and font, etc., and this information can be used in subsequent filtering and prioritization processes described further below.
[0044] Voice recognition technology can be used to assess the original source context and extract information that can help describe the content of the chart and/or help align the description of the image back into the original source content.
[0045] Translation technology can be employed to rephrase the content from one context to another context that it more suitable for the final purpose.
[0046] In accordance with another embodiment, the method can analyze other source content in relation to the interpreted images to align the two content types. Natural language processing and a semantic electronic dictionary can be used for measuring the semantic similarity distance between images and the other source content. Locations with the shortest similarity distance in the other source content can be used to place the images. Since most presentations often follow a logical order once a correct reference point is established, it is easier to place the interpreted image description back into the presentation.
[0047] Independent control over the descriptive additions allow the user to apply this method to previous and future image from the original source content. This will help align the deciphering system to the original audio or text that can then be used as a reference point to continue deciphering and alignment. The alignment process need only happen once as users can download the annotated version of the presentation, and not the source and the augmentation information separately.
[0048] An illustrative method 200 in accordance with an embodiment of the present invention is now described with reference to FIG. 2 . As shown, a list of images (e.g., as used in a presentation) is received at block 202 as an input. Method 200 then proceeds to block 204 , where for each image, method 200 determines the image type. At block 206 , method 200 pre-processes the image based on the image type (as described in further detail with respect to FIG. 3A and 3B below), then proceeds to decision block 208 to evaluate the success of the image type determination. At decision block 208 , if the answer is no, method 200 proceeds to block 210 for further pre-processing, possibly using meta-tags and pattern mapping, then to block 212 where method 200 can learn new patterns. Method 200 returns to block 204 with this new information for further pre-processing.
[0049] If, at decision block 208 , the answer is yes, method 200 proceeds to block 214 , where method 200 processes and generates a list of image keywords associated with the image. Method 200 then proceeds to block 216 , where method 200 can eliminate extraneous words (e.g., page number, copyright notice). Method 200 then proceeds to block 218 , where method 200 generates a description of the image based on the image keywords. Method 200 then proceeds to block 220 , where method 200 determines if there are more images. If yes, method 200 returns to block 204 and continues. If no, method 200 proceeds to connector D ( FIG. 6 ).
[0050] FIGS. 3A and 3B show a schematic flowchart of an illustrative data source determining and pre-processing method 300 in accordance with an embodiment of the present invention. Method 300 begins at block 302 , and at block 304 receives the source data or image. At decision block 306 , method 300 determines if the source is an image file (e.g., jpeg, pdf) or a data file (e.g., ppt, vsd). If a data file, method 300 proceeds to block 308 , where the data files are expected to have additional information stored digitally (e.g., doc, ppt, vsd, xis, 123 , etc.). Method 300 then proceeds to decision block 310 , where method 300 determines if the data file contains additional meta-tags to assist in the image interpretation. If no, method 300 proceeds directly to block 502 ( FIG. 5A ) via connector C. If yes, method 300 proceeds to block 312 , where method 300 parses and interprets the meta-tags. These meta-tags can be industry standards, or tags specific to the source file types. Method 300 then proceeds to connector C.
[0051] If, at decision block 306 , the source is instead an image file, method 300 proceeds to block 314 via connector A 2 ( FIG. 3B ). As image files typically have less retrievable meta-data, method 300 proceeds to block 316 , where method 300 can prepare the image file for other types of analysis. This preparation can include, for example, de-skewing, noise reduction, signal to noise averaging, etc. Method 300 can then proceed to block 318 , where a pattern resulting from the preparation can be compared against patterns or templates stored in a pattern portfolio to determine the likely type of the source image. For example, the pattern or template matching can indicate that the source image is a bar chart, a pie chart, a text table, a line chart, etc. Various techniques for image analysis can be used with the present method are briefly discussed at http://en.wikipedia.org/wiki/Computer vision. For example, various methods for noise reduction are described http://www.mathtools.net/Java/lmage Processing/. Graphic image processes including de-skewing, automatic cropping, automatic border extraction, and removal of noise artifacts are described at http://www.sharewareriver. com/products/6116.htm. Optical character recognition (OCR) techniques are described at http://www.nuance.com/omnipage/professional/ and http://www.csc.liv.ac.uk/˜wda2003/Papers/Section IV/Paper 14.pdf. Using contrast techniques to segment items from an image is described at http://www.ph.tn.tudelft.nl/Courses/FIP/noframes/fip-Segmenta.html. Circle and curve determination techniques are described at http://homepages.inf.ed.ac.uk/cgi/rbf/CVONLINE/entries.pl7TAG382. Figure to data conversion line techniques are described at http://ichemed.chem.wisc.edu/iournal/issues/2003/Sep/abs10932.html. Color edge detection techniques for bars graphs, pie charts, etc. are described at http://ai.stanford.edu/˜ruzon/compass/color.html. Volume determination (for venn diagrams, pie charts, etc.) are described at http://www.spl.harvard.edu:8000/pages/papers/guttmann/ms/guttmann_rev.html.)
[0052] Method 300 then proceeds to block 320 , where method 300 processes the source image file based on its likely type. For example, if the source content is a bar chart, a corresponding template for bar charts can be retrieved and the bar chart contents can be analyzed using the template for interpretation and description. Blocks 318 and 320 are repeated as necessary until an optimal fit is achieved in block 322 . Flow then passes to block 402 via connector B.
[0053] Now referring to FIG. 4 , shown is an image file processing method 400 in accordance with an embodiment of the present invention. Method 400 begins at block 402 and proceeds to decision block 404 to determine if a pattern in a pattern portfolio exceeds a predetermined threshold, suggesting that the source image file type has been matched. If yes, method 400 proceeds to block 502 ( FIG. 5A ) via connector C. If no, method 400 proceeds to block 406 , where method 400 pre-processes and compares the image file with the “best fit” pattern from the existing pattern portfolio. Method 400 then proceeds to decision block 408 .
[0054] At decision block 408 , if a minimum threshold cannot be met, the image cannot be interpreted and described (e.g., the image can be of an abstract painting, or a sketch drawn freehand), and method 400 returns to block 302 via connector A. If, at block 408 , the minimum threshold can be met, method 400 proceeds to block 410 . At this step 410 , the system can log the image as a potential new pattern and without any further processing, flow passes to block 302 via connector A. At the end of the process, the list of potential new pattern images can be reviewed (e.g., by a system analyst), and new templates for data extraction based on the pattern can be generated. These new templates can then be saved in the pattern portfolio, so they can be used in the next rounds of automated processes.
[0055] Now referring to FIGS. 5A and 5B , shown is a schematic flowchart of a component assembly method 500 in accordance with an embodiment of the present invention. Method 500 begins at block 502 and proceeds to decision block 504 , where method 500 determines if the source file is an image file (e.g., jpeg, pdf) or a data file (e.g., ppt, vsd).
[0056] If a data file, method 500 proceeds to block 506 , where method 500 applies a template to extract content from the data, including attributes, context, numerical values, etc. For example, a template for an x-y graph can extract information such as titles, name of the x-axis, name of the y-axis, details for lines drawn in the chart, and any labels for the lines. It will be appreciated that the templates can be drafted for each specific type of data file in order to extract key information.
[0057] Method 500 then proceeds to block 508 , where method 500 can construct logical text structures, and populate them from the data extracted using the template. For example, in order to describe an x-y graph, the text structures can include the title, name of the x-axis, name of the y-axis, and text structures to describe straight lines by their slopes and relative positions in the x-y graph. Method 500 then proceeds to block 510 , where method 500 can store the results of the segmentation processes as identifiable components in the logical structures. Method 500 then proceeds to block 302 ( FIG. 3A ) via connector A.
[0058] FIG. 5B shows the steps of method 500 if, at decision block 504 , the source file is an image file. Method 500 proceeds to block 514 via connector C 2 where a selected pattern or template is used to segment the image file into components (e.g., legend, axis, title, etc.).
[0059] Method 500 then proceeds to one or more of blocks 516 , 518 , 520 , 522 , 524 , 526 to interpret the image file. For example, at block 516 , method 500 can use OCR to determine the text content. At block 518 , method 500 can use edge finding technology to find a line graphical component. At block 520 , method 500 can use color edge technology to find a line graphical component. At block 522 , method 500 can use curve finding technology to find a curved line graphical element. At block 524 , method 500 can use circle, ellipse, and blob finding technology to find 2-D graphical components. At block 526 , method 500 can use contrast finding technology to find bars, pie segments, etc.
[0060] Method 500 then proceeds to block 528 , where method 500 can interpret each found object for numbers, labels, or other attributes such as the relative position of bars from left to right, relative percentages of pie segments, etc. Method 500 then proceeds to block 530 , where method 500 can document segmented elements discovered from applying one or more analysis techniques as described above. Method 500 then proceeds to block 532 , where method 500 can coordinate and align the components. Method 500 then proceeds to block 508 ( FIG. 5A ) via connector C 3 as described above and continues.
[0061] Now referring to FIG. 6 , shown is a schematic flowchart of an audio pre-processing method 600 . Method 600 begins at block 602 and proceeds to block 604 to receive an audio recording as an input. Method 600 then proceeds to block 606 , where method 600 divides the audio program into a vector of audio clips, each audio clip ends at a natural pause in the speech, such as the end of a sentence, and close to a fixed length (e.g., 30 seconds).
[0062] Method 600 then proceeds to block 608 , where method 600 continues for each audio clip. Method 600 proceeds to block 610 , where voice recognition techniques can be used to translate the audio clip into text. At block 612 , method 600 can then use a natural language parser to parse the translated text. Method 600 can then produce a noun phrases vector that contains 0 to n noun phrases extracted from the audio clip. Method 600 then proceeds to block 616 , where method 600 maps certain common names or names not found in a dictionary to words in the dictionary. Method 600 then proceeds to block 618 , where method 600 calculates the importance value of each noun phrase, and removes less meaningful ones. Method 600 then proceeds to block 620 , where method 600 produces a keywords vector for the audio clip that contains 0 to n keywords. Method 600 then proceeds to decision block 622 to determine if there are more audio clips. If yes, method 600 returns to block 608 and continues. If no, method 600 proceeds via connector E to block 702 of method 700 of FIG. 7 .
[0063] Now referring to FIG. 7 , shown is an image insertion location search method 700 in accordance with an embodiment. Method 700 begins at block 702 , and proceeds to block 704 , where method 700 receives as an input a pre-processed image represented by an image keyword vector containing 0 to n keywords, and a pre-processed audio program represented by a vector of audio clip keyword vectors (where each audio clip keyword vector represents an audio clip).
[0064] Method 700 then proceeds to block 706 , where method 700 continues for each audio clip in the audio program. At block 708 , method 700 continues for each keyword in the image keyword vector. Method 700 then proceeds to block 710 , where method 700 continues for each keyword in an audio keyword vector representing an audio clip. Method 700 then proceeds to block 712 , where method 700 calculates the similarity distance between the current image keyword and audio keyword. At block 714 , method 700 updates the shortest distance between this image keyword and audio keyword, and goes to the next keyword in the audio clip, if present, by returning to block 710 . If not, method 700 proceeds to block 716 where method 700 assigns this shortest distance value as the similarity distance between this image keyword and audio clip. Method 700 then proceeds to block 718 , where method 700 updates the shortest distance between this image keyword and audio clip, and goes to the next keyword in the image, if present, by returning to block 708 . If not, method 700 proceeds to block 720 , where method 700 assigns this shortest distance value as the similarity distance between this image and the audio clip. Method 700 then proceeds to block 722 , where method 700 records the audio clip with the shortest distance, and goes to the next audio clip, if present, by returning to block 706 . If not, method 700 proceeds to block 724 , where method 700 identifies the audio clip with the shortest similarity distance to the image as the place to insert the image. Method 700 then proceeds to block 802 ( FIG. 8 ) via connector F.
[0065] Now referring to FIG. 8 , shown is an image insertion method 800 in accordance with an embodiment. Method 800 begins at block 802 and proceeds to block 804 to receive an input of a list of images, each image represented by an image keyword vector and a corresponding insertion point. Method 800 then proceeds to block 806 , where method 800 continues for each sound clip in a sound recording. Method 800 then proceeds to block 808 to append this sound clip to the resulting image description augmented sound recording.
[0066] Method 800 then proceeds to block 810 to continue for each image in the list of images. Method 800 then proceeds to decision block 812 to determine if the image should be inserted after the current sound clip. If no, method 800 returns to block 810 . If yes, method 800 proceeds to block 814 to generate an image description audio clip from the image keywords using voice generation tools. Method 800 then proceeds to block 816 , where method 800 appends the newly generated image description audio clip at the identified insertion point. Method 800 then proceeds to decision block 818 to determine whether to return to block 810 , or to proceed to decision block 820 . At decision block 820 , method 800 determines whether to return to block 806 , or to end.
[0067] As will be appreciated, the above described methods identify and describe images in text and audio, locate the appropriate point of insertion in the original audio recording using similarity distances calculated based on keywords, and insert the image description at the appropriate identified location. Thus, images that would otherwise not be viewed by a listener of the audio recording will now be described in an image description audio clip inserted into and augmenting the original sound recording.
EXAMPLE
[0068] FIG. 9 shows an illustrative example of a graphic image 900 , that can be identified and described using the method as described above.
[0069] For example, in an audio recording of a lecture, the lecturer can refer to a number of graphics or charts, such as the graphic image 900 shown in FIG. 9 . At some point in the lecture, e.g., at a time reference of 10:25 am, the lecturer can make reference to a chart with the title “disruptors”. Then at 10:30 am he can say “diagram” and “line” which can be interpreted as him referring to a line chart. He can also specifically says at 10:35 am “to keep the diagram simple I'll just depict that ability to use improvement as a single line . . . ”
[0070] In accordance with an embodiment, the system can imbed an interpreted description of the chart 900 at 10:30 am, which can state the following: Title: “disruptions”, X-axis: “time”, Y-axis: “performance”. Line A with a slope of about 10° entitled “Ability to use improvement”. Line B with a slope of about 25° entitled “Innovations”. Line B intersects Line A at time D. Line C with a slope of about 25° entitled “Disruptions”. Line C intersects line A at time E.
[0071] As will be appreciated, a system and method that can interpret charts such as chart 900 and provide a verbal description can provide a listener with more context to understand the lecture than if such information was not provided. While various illustrative embodiments of the invention have been described above, it will be appreciated by those skilled in the art that variations and modifications can be made. Thus, the scope of the invention is defined by the following claims.
|
There is disclosed a system and method for interpreting and describing graphic images. In an embodiment, the method of inserting a description of an image into an audio recording includes: interpreting an image and producing a word description of the image including at least one image keyword; parsing an audio recording into a plurality of audio clips, and producing a transcription of each audio clip, each audio clip transcription including at least one audio keyword; calculating a similarity distance between the at least one image keyword and the at least one audio keyword of each audio clip; and selecting the audio clip transcription having a shortest similarity distance to the at least one image keyword as a location to insert the word description of the image. The word description of the image can then be appended to the selected audio clip to produce an augmented audio recording including the interpreted word description of the image.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119(e) from U.S. Provisional Patent Application No. 61/614,099 filed on Mar. 22, 2012, the contents of which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to the field of calibration of devices used to measure mass or the volumetric flow rate of a liquid or gas and more particularly, to flowmeters comprising a pressure sensor connected in bypass to a flow tube inducing differential pressure as function of measured flow.
BACKGROUND OF THE ART
[0003] Gas flowmeters typically operate on the basis of two functional elements: a) a flow element inducing differential pressure when gas flows through it and b) a pressure sensor measuring the induced differential pressure. If an output signal of the sensor is a monotonic function of the differential pressure and the differential pressure is a monotonic function of the flow, then the value of the flow can be unambiguously defined from the output of the pressure sensor. A calibration curve of a flowmeter which presents the function “flow versus sensor output” depends on the design of the flow tube and on the pressure response of the sensor. Due to the variability in sensor sensitivity and in geometrical parameters of the flow tubes, each individual flowmeter must usually pass through a calibration process.
[0004] Thermal type micro-flow sensors are frequently used as low differential pressure sensors in gas flowmeters due to their wide dynamic range, low noise and low offset compared to membrane-type pressure sensors. A specific feature of such a micro-flow sensor is a large nonlinearity of the pressure response and an essential temperature dependence of its sensitivity. Linearization and temperature compensation of these sensors is not a trivial task as it requires special skills, specific calibration equipment, and time and labor associated with the calibration process. For this reason, calibration of the differential pressure sensor is usually performed by the original sensor manufacturer.
[0005] In practice, linearized and temperature compensated differential pressure sensors contain a sensor conditioner which can be either integrated with the sensing element on one Silicon chip or be used as a separate IC co-packaged with the sensing element. Typically, the sensor conditioner provides Analog-to-Digital (A-to-D) conversion of the analog output signals from the sensing element, processing of digitized signals, storage of sensor-specific calibration coefficients, lookup tables, and realization of certain digital communication interface(s).
[0006] One of the traditional approaches of gas flowmeter calibration is based on the use of pre-calibrated differential pressure sensors with a final calibration of the whole flowmeter. This additional calibration is needed due to the variability of the flow tubes. As a result, two separate calibration processes are usually performed—one on a sensor level (done by the sensor manufacturer) and another on a device level (done by the flowmeter manufacturer).
[0007] There is a need to improve the two-part calibration process for gas flowmeters in order to address some of the existing drawbacks.
SUMMARY
[0008] There is described herein a method for calibrating gas flowmeters comprising only one calibration procedure performed at the device level. The step of calibrating the differential pressure sensor itself may be omitted, and the design of the sensor may therefore be simplified by eliminating the sensor conditioner and instead using a microcontroller on the device for signal processing. This is done by a two-point calibration procedure with the use of three correction coefficients to compensate for the variability of flow tubes and pressure sensors.
[0009] In accordance with a first broad aspect, there is provided a method for calibrating a flowmeter comprising a flow tube inducing a differential pressure dP as a function of flow f and a pressure sensor connected in bypass to the flow tube and generating an output signal U as function of the differential pressure dP, wherein a nonlinearity of the pressure sensor is negligible in a first sub-range of differential pressures and non-negligible in a second sub-range of differential pressures higher than the first sub-range, the method comprising: defining a flow tube calibration curve as
[0000]
f
=
F
(
dP
c
F
)
,
[0000] which is inverse to a flow-to-pressure response dP=c F P F (f), and where c F defines a deviation of the flow-to-pressure response from a nominal response P F (f); defining a pressure sensor calibration curve as dP=c P P P (U,K), where P P (U,1) is a nominal calibration curve and coefficients c P and K define a deviation of the pressure sensor calibration curve from nominal; measuring a first output signal U 1 at a first flow level f 1 when induced differential pressure belongs to the first sub-range at which the nonlinearity of the pressure sensor is negligible; measuring a second output signal U 2 at a second flow level f 2 when induced differential pressure belongs to the second sub-range at which the nonlinearity of the pressure sensor is non-negligible; determining a first correction coefficient C=c P /c P from
[0000]
f
1
=
F
(
c
P
c
F
P
P
(
U
1
,
K
)
)
;
[0000] and determining a second correction coefficient K from
[0000]
f
2
=
F
(
c
P
c
F
P
P
(
U
2
,
K
)
)
.
[0010] In accordance with a second broad aspect, there is provided a method for determining flow during operation of a flowmeter comprising a flow tube inducing a differential pressure dP as a function of flow f and a pressure sensor connected in bypass to the flow tube and generating an output signal U as function of the differential pressure dP, the method comprising: retrieving from memory a first correction coefficient C=c P /c F and a second correction coefficient K, wherein c P and K correspond to a deviation of an individual pressure sensor calibration curve from nominal, the individual pressure sensor calibration curve defined as dP=c P P P (U,K), where P P (U,1) is a nominal calibration curve, and wherein c F corresponds to a deviation of an individual flow tube flow-to-pressure response dP=c F P F (f) from a nominal response P F (f) and an individual flow tube calibration curve is defined as
[0000]
f
=
F
(
dP
c
F
)
;
[0000] determining flow f as a function of the output signal U using
[0000]
f
=
F
(
c
P
c
F
P
P
(
U
,
K
)
)
.
[0011] Since coefficients c F and c P , which determine the deviation of a flow tube response and a pressure sensor response from a nominal (or “ideal”) response, cannot be measured individually when a flow tube and a pressure sensor are connected together in one flowmeter, the present method proposes a two measurement calibration process for determining two unknown coefficients. Using the ratio C=c P /c F , full calibration of the flowmeter may be provided.
[0012] A sensor response curve should be understood as a function relating an input parameter and a sensor output. For example, a pressure response curve relates an input differential pressure and an output voltage.
[0013] Sensitivity is a property of a sensor response curve. For parts of the response curve which are linear, the sensitivity is the slope or proportionality constant relating output and input parameter in that linear portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which:
[0015] FIG. 1 shows a sequence of exemplary calibration steps of the flowmeter comprising a flow tube inducing differential pressure as a second order polynomial function of flow;
[0016] FIG. 2 shows a sequence of calibration steps of the flowmeter comprising a flow tube inducing differential pressure as a square function of flow;
[0017] FIG. 3 illustrates measured pressure response curves of eight differential pressure sensors;
[0018] FIG. 4 presents pressure response curves of artificially uncalibrated sensors;
[0019] FIG. 5 shows simulated flow-to-differential pressure curves of the flow tubes;
[0020] FIG. 6( a ) illustrates an example of a flow-to-voltage response reconstructed after two-point calibration;
[0021] FIG. 6( b ) presents examples of simulated flow-to-voltage responses of several flowmeters; and
[0022] FIG. 7 shows an error of linearization of the flow response of the flowmeter.
[0023] It will be noted that throughout the appended drawings, like features are identified by like reference numerals.
DETAILED DESCRIPTION
[0024] The method will be described as applied to a gas flowmeter consisting of two main functional elements—a flow tube and a differential pressure sensor connected in bypass to the flow tube. The flow tube generates differential pressure dP as a monotonic function of the gas flow f passing through it. For the tubes of Venturi- or Pitot-type, or tubes containing a baffle (orifice plate), the differential pressure generated can be expressed as:
[0000] dP=af+bf 2 (1a)
[0025] where coefficients a and b define a nominal flow response of the tube. The differential pressure dP is close to a square function of flow at medium and high flow.
[0026] Due to variations of geometrical parameters, the actual differential pressure of the individual flow tube may be different from its nominal value:
[0000] dP=c F ( af+br 2 ) (1b)
[0027] where the coefficient c F represents a deviation of the flow-to-pressure response of the flow tube from its nominal response (c F =1 for nominal response).
[0028] The differential pressure sensor converts the pressure dP into an electrical output signal U. As described in PCT Patent Application bearing publication No. WO2011/029182, the contents of which are hereby incorporated by reference, the calibration curve of a micro-flow sensor can be approximated as follows:
[0000]
dP
=
c
P
G
o
U
1
-
(
KU
U
o
)
N
,
(
2
)
[0029] where coefficients G o and U o define the nominal sensitivity and the level of nonlinearity of the sensor, respectively; coefficients c P and K represent a deviation of the actual calibration curve from nominal calibration curve (c P =1 and K=1 for nominal calibration curve); and N represents a coefficient defining curvature of the calibration curve (the higher the N, the more linear the response at low and medium dP and the more rapidly the curve goes up at higher dP).
[0030] The calibration method described herein allows calibration of a flowmeter consisting of an uncalibrated flow tube (unknown coefficient C F ) and an uncalibrated differential pressure sensor (unknown coefficients c P and K).
[0031] In a first step, the calibration coefficients and an analytical formula are defined for the flow response curve. The calibration curve of the flowmeter can be derived from equations (1b) and (2):
[0000]
af
+
bf
2
=
c
P
c
F
G
o
U
1
-
(
KU
U
o
)
N
(
3
a
)
f
=
A
[
-
1
+
1
+
c
P
c
F
B
G
o
U
1
-
(
KU
U
o
)
N
]
,
(
3
b
)
[0032] where
[0000]
A
=
a
2
b
and
B
=
4
b
a
2
.
[0000] To define the ratio c P /c F , a first measurement at low flow f 1 is performed. The nonlinearity of the pressure sensor can be neglected at low pressure, and the ratio c P /c F can be found from (3a) using:
[0000]
c
P
c
F
=
af
1
+
bf
1
2
G
o
U
1
,
(
4
)
[0033] where U 1 is the output signal of the sensor measured at flow f 1 .
[0034] To define coefficient K, a second measurement at flow f 2 is used. The flow should be high enough to provide an output signal U 2 close to its full scale, where nonlinearity of the sensor pressure response becomes significant. Coefficient K can be found from (3a) after defining of ratio c P /c F in (4):
[0000]
K
=
U
o
U
2
(
1
-
c
P
c
F
G
o
U
2
af
2
+
bf
2
2
)
1
N
(
5
)
[0035] Therefore just two calibration measurements at flows f 1 and f 2 are used to define device-specific coefficients c P /c F and K, which may be stored in a memory of the device and used later. In real operation, the output signal of the flowmeter U is measured and is used to calculate the actual flow in accordance with equation (3b).
[0036] The steps described above were performed using only room temperature calibrations and operations. However, temperature variations may result in distortions of the flow-to-pressure response of the flow tube and the pressure-to-voltage response of the sensor. These distortions can be mathematically described by replacing the set of coefficients in equations (1)-(5) with corresponding temperature-dependent functions as follows:
[0000] a→a ( T F ); b→b ( T P ); A→A ( T F ); B→B ( T F ) (6a)
[0000] G o →G o ( T P ); K→KK o ( T P ) (6b)
[0037] where T F and T P are the temperatures of gas flow inside the flow tube and the sensor. In general these two temperatures may be different. G o (T) describes temperature dependence of the nominal sensitivity at low differential pressures. K o (T) describes temperature-induced change of the nonlinearity of a pressure response at medium and high pressures. K o (T o )=1 and G o (T o )=G o at room temperature T o .
[0038] Functions A(T), B(T), G o (T) and K o (T) may be defined in advance for flow tubes of a same construction and sensors of a same type. These functions represent the best approximation describing temperature behavior of the flowmeters incorporating these two components. None of these functions is meant to be measured during calibration of each individual flowmeter.
[0039] Temperature compensation of the flowmeter response may require additional sensors to measure the actual temperature of the gas flow inside the flow tube and the temperature of the pressure sensor. In the latter case, a temperature sensor can be, for example integrated with a pressure-sensitive element or with an on-board microcontroller.
[0040] Each one of the temperature-dependent functions may be approximated with a polynomial function and the appropriate approximation coefficients may be stored in a memory. These coefficients may be used for the calculation of values of functions (6a) and (6b) at an operating temperature, which are used further in the calculation of flow in accordance with equation (3b).
[0041] The output of the sensor U and temperatures T F and T P may be measured at certain sampling rates. After the coefficients A(T F ), B(T F ), G o (T P ) and K o (T P ) are calculated, their values and the value of the sensor output U may be substituted into equation (3b) to calculate flow.
[0042] The calculation of analytical expressions such as (3b) may be impossible for simple microcontrollers with a restricted number of computing instructions. Therefore, in some embodiments, lookup tables are used for calculation of flow. For example, lookup tables may be built for analytical functions
[0000]
Z
(
U
)
=
G
o
U
1
-
(
U
U
o
)
N
[0000] and Y(z)=−1+√{square root over (1+z)}, and stored in a memory. The same lookup tables may be used for all flowmeters of one type and without being dependent on the calibration coefficients defined during the individual calibration of each flowmeter.
[0043] FIG. 1 is a flowchart illustrating an exemplary calculation of flow during operation of the device. In a first step, a sensor output U and temperatures T F and T P are measured. Values are then calculated for A(T F ), B(T F ), G o (T P ) and K o (T P ). The sensor output U may then be multiplied by coefficients K and K o (T P ), such that U 1 =KK o (T P )U. As per the embodiment described above, the value Z 1 =Z(U 1 ) may be determined from a lookup table for Z(U). The obtained value Z 1 is then multiplied by G o (T P ) and divided by KK o (T P ), resulting in Z 2 =G o (T P )Z 1 /KK o (T P ). Value Z 2 is multiplied by c P /c F and B(T F ) to give
[0000]
Z
3
=
c
P
c
F
B
(
T
F
)
Z
2
.
[0044] A second lookup table may again be used to define Y 1 =Y(Z 3 ). Finally, Y 1 is multiplied by A(T F ) to calculate flow: f=A(T F )Y 1 .
[0045] To calculate the value of flow using the present method, a limited number of low level microprocessor instructions, like arithmetic addition, multiplication, negation, etc, are used. The calculation of flow can be further simplified if the differential pressure generated by the flow tube is approximated by a pure square function of flow:
[0000] dP=c F bf 2 (7)
[0046] In this case, the calibration curve of the flowmeter may be defined as:
[0000]
bf
2
=
c
P
c
F
G
o
U
1
-
(
KU
U
o
)
N
(
8
a
)
f
=
1
b
c
P
c
F
G
o
U
1
-
(
KU
U
o
)
N
(
8
b
)
[0047] Calibration coefficients c P /c F and K are found as was described above at low flow f 1 and high flow f 2 :
[0000]
c
P
c
F
=
bf
1
2
G
o
U
1
(
9
a
)
K
=
U
o
U
2
(
1
-
c
P
c
F
G
o
U
2
bf
2
2
)
1
N
(
9
b
)
[0048] The calculation of flow during device operation can be realized with a simpler approach than that described above. One lookup table can be built for the analytical function
[0000]
W
(
U
)
=
G
o
U
1
-
(
U
U
o
)
N
[0000] and stored in the device memory. Functions 1/√{square root over (b(T))}, √{square root over (G o (T))}, K o (T) and √{square root over (K o (T))} may be defined in advance for flow tubes of a same construction and sensors of a same type, as was described above. Each of these temperature-dependent functions may be approximated with polynomial functions and appropriate approximation coefficients may be stored in the device memory. Coefficients K, √{square root over (K)} and √{square root over (c P /c F )}, defined at the time of calibration of an individual flowmeter, may also be stored.
[0049] FIG. 2 illustrates exemplary calculation steps, as per FIG. 1 , which can be applied for the flowmeter comprising a flow tube inducing a differential pressure dP as a square function of flow. In a first step, the sensor output U and temperatures T F and T P are measured. This is followed by the calculation of values for 1/√{square root over (b(T F ))}, √{square root over (G o (T P ))}, K o (T P ) and √{square root over (K o (T P ))}. The sensor output U is multiplied by coefficients K and K o (T P ) to give U 1 =KK o (T P )U. The value W 1 =W(U 1 ) may be defined from the lookup table W(U). The obtained value W 1 is then multiplied by √{square root over (G o (T P ))}, √{square root over (c P /c F )} and divided by √{square root over (KK o (T P ))}:
[0000]
W
2
=
c
P
G
o
(
T
P
)
c
F
KK
o
(
T
P
)
W
1
.
[0000] Finally, W 2 is multiplied by 1/√{square root over (b(T F ))} to calculate flow:
[0000]
f
=
W
2
b
(
T
F
)
.
[0050] It should be noted that in the presented analysis, the offset of the pressure sensor is assumed to be zero. In practice, an offset compensation procedure may be included into the calibration process. For example, an output of the flowmeter may be measured at zero flow, stored in a memory of the device and subtracted from the measured output signal during operation. In this embodiment, the calibration process may include three measurements—one measurement at zero flow (offset compensation), one measurement at low flow f 1 (defining of coefficient c P /c F ), and one measurement at high flow f 2 (defining of coefficient K).
[0051] Simulation results of the flowmeter calibration process in accordance with the present method are provided below. The pressure response of a real 500 Pa micro-flow differential pressure sensor was used in simulation. FIG. 3 shows the measured pressure response of eight pressure sensors passed through calibration of low pressure sensitivity. The sensors have different nonlinearities at medium and high pressures and the same sensitivity at low pressures. The parameters of the reference calibration curve for the sensors are G o =0.081 Pa/mV, U o =5525 mV, N=2.2.
[0052] To imitate uncalibrated sensors, their response was multiplied by random numbers from 0.6 to 1.4, which is equivalent to +/−40% variation of sensitivity. Simulated pressure-to-voltage curves derived from initial pressure responses are illustrated in FIG. 4 .
[0053] A hypothetical flow tube was modeled to create a flow-to-pressure response (as per equation (1b)), with a=0.1 Pa/lpm, b=0.0215 Pa/lpm 2 and c F =1. The flow tube generates 500 Pa differential pressure at 150 lpm flow. To imitate the variability of flow tubes, coefficient c F was chosen to be 0.8, 0.9, 1.1 and 1.2. The flow-to-pressure responses of five hypothetical flow tubes are shown in FIG. 5 .
[0054] The pressure sensors were initially calibrated at eleven points from 0 to 500 Pa with intervals of approximately 50 Pa. Each pressure-voltage point corresponds to a given flow calculated from equation (1b). Based on this data, a flow-versus voltage curve can be simulated. FIG. 6 b gives an example of the flow response of several flowmeters, each “assembled” from one of five flow tubes and one of eight pressure sensors.
[0055] To imitate the proposed two-point calibration process, two measurements done at ˜50 Pa and ˜450 Pa were chosen for each sensor. Gas flow values corresponding to these two reference pressures were calculated from equation (1b) for each of the five flow tubes. Eventually, two pairs of flow-voltage points were chosen for each sensor connected with each of the five flow tubes, as per table 1.
[0000]
TABLE 1
dP, Pa
flow
sensor output
~50
f 1
U 1
~450
f 2
U 2
[0056] Coefficients c P /c F and K were calculated from equations (4) and (5) for the flowmeter consisting of all possible combinations of pressure sensors and flow tubes. After the two-point calibration, a flow-versus-voltage curve was reconstructed such that flow was calculated for all eleven voltage values in accordance with equation (3b) and compared with the initial curve. The “reconstructed” flow response of the flowmeter, built after two-point calibration, is shown in FIG. 6 a . Deviations of the reconstructed curves from the simulated ones are shown on FIG. 7 for some combinations of the pressure sensors and flow tubes. The data indicates that the maximum deviation is less than 0.8 lpm for all possible combinations of the sensors and flow tubes.
[0057] It should be understood that the embodiments described above serve as examples for the demonstration of the proposed method of flowmeter calibration. There are possible modifications of the described embodiments which do not change the main principles of the method. For example instead of equation (2) describing pressure response of the sensor, another approximation function can be used:
[0000]
dP
=
c
P
G
o
U
1
-
(
KU
U
o
)
N
1
1
-
(
KU
U
o
1
)
N
1
(
10
)
[0058] Calculation of the coefficient K from equation (10) can be done numerically.
[0059] A more generic case of the method may be considered as follows. The flow tube generates differential pressure dP as a monotonic function of flow f as:
[0000] dP=c F P F ( f ) (11)
[0060] where P F (f) is the nominal flow-to-pressure response. The function f=F(dP) inverse to the function dP=P F (f) is determined to define flow from the measured differential pressure as follows:
[0000]
f
=
F
(
dP
c
F
)
(
12
)
[0061] A pressure sensor connected in bypass to the flow tube and measuring differential pressure dP has a generic calibration curve as follows:
[0000] dP=c P P P ( U,K ) (13a)
[0062] where coefficients c P and K define a deviation of the individual sensor pressure response from the nominal response. It is assumed that at low pressure, the sensor response is essentially linear and does not depend on coefficient K, thus giving:
[0000] dP=c P G o U (13b)
[0063] where G o is the nominal low-pressure sensitivity.
[0064] The equation used for calculation of the calibration coefficient c P /c F at low flow f 1 may be derived from (12) and (13b):
[0000]
f
1
=
F
(
c
P
c
F
G
o
U
1
)
(
14
)
[0065] Note that equations (4) and (9a) described above are specific cases of the more general equation (14).
[0066] A second calibration coefficient K is found at high flow f 2 from an equation derived from (11) and (12a):
[0000]
f
2
=
F
(
c
P
c
F
P
P
(
U
2
,
K
)
)
(
15
)
[0067] Coefficient K can be calculated either numerically, as in equation (10), or analytically as in equations (5) or (9b).
[0068] The described calibration method may be used to improve accuracy of flowmeter calibration. It also minimizes the number of calibration points needed for linearization of the flowmeter, as well as the number of calibration coefficients used in linearization. The linearization algorithm is thus simplified, and can be implemented by a microcontroller with minimal usage of computational resources and memory.
[0069] It should be understood that in some embodiments, the method may involve one or more additional steps of determining the particular expressions for flow-to-pressure response of a flow tube and calibration curve of a pressure sensor similar to those described above or different therefrom. Alternatively, the method may involve being given functions such as P F (f), F(dP), P P (U,K) and using these functions for the calibration of the flowmeter.
[0070] It will be understood by those skilled in the art that the present embodiments are provided by a combination of hardware and software components, with some components being implemented by a given function or operation of a hardware or software system, and many of the data paths being implemented by data communication within a computer application or operating system. The present invention can be carried out as a method, can be embodied in a system or on a computer readable medium. The embodiments of the invention described above are intended to be exemplary only. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.
|
There is described herein a method for calibrating gas flowmeters comprising only one calibration procedure performed at the device level. The step of calibrating the differential pressure sensor itself may be omitted, and the design of the sensor may therefore be simplified by eliminating the sensor conditioner and instead using a microcontroller on the device for signal processing. This is done by a two-point calibration procedure with the use of three correction coefficients to compensate for the variability of flow tubes and pressure sensors.
| 6
|
BACKGROUND OF INVENTION
1. Field of the Invention
The present invention is directed to a drive system, and more particularly to a drive system for operating a pair of counter rotating air propellers that propel an airboat.
2. Background Information
Drive systems for propelling airboats are known in the art. For example, U.S. Pat. No. 6,540,570 B1 issued to Eakin on Apr. 1, 2003. This reference illustrates an airboat where the engine is mounted high above the hull. A small compact transmission is driven by the engine through a belt connection located between a drive shaft and a sprocket. A number of gears transmit power from the engine and rotate the air propellers.
Other examples of prior art airboat drive systems include:
(a) U.S. Pat. No. 5,839,926 issued to K-Way on Nov. 24, 1998, (b) U.S. Pat. No. 6,053,782 issued to Bell on Apr. 25, 2000, (c) U.S. Pat. No. 6,478,641 issued to Jordan on Nov. 12, 2002, (d) U.S. Pat. No. 5,724,867 issued to Jordan on Mar. 10, 1998, and (e) U.S. Pat. No. 6,299,485 issued to Jordan on Oct. 9, 2001.
All of these references illustrate an engine mounted high above the hull of an airboat. A single compact transmission is driven by a direct connection to the engine through a drive shaft. A number of gears are provided to operate a pair of output drive shafts. One of the output drive shafts is hollow and surrounds the other solid drive shaft to rotate the air propellers.
The prior art airboat drive system references consistently teach mounting an engine high above the hull of an airboat in combination with a single compact transmission. Keeping the engine high and the transmission compact provides the necessary clearance between the tips of the air propellers and the hull of the airboat.
However, there are a number of problems with the prior art airboat drive systems. The transmissions are overly complex with many gears. They require multiple long output drive shafts, including a solid output drive shaft located within a hollow output drive shaft. Mounting the engine and drive system high above the hull creates a high center of gravity. The compactness, and horizontal input and output shafts of these transmissions renders the transmission completely unusable in situations when an engine is mounted low in the hull of an airboat.
Another example of a prior art drive system is shown in the Husky™ Nattiq™ airboat (www.huskyairboats.com). This airboat has the engine mounted low in the hull of an airboat. The existing drive system is an elongated belt extending from a pulley mounted on an end of a drive shaft of an engine to another pulley mounted on a air propeller drive shaft. However, external belt drives are very noisy, prone to wear, and can become dangerous upon failure of the belt.
Other examples of prior art marine drive systems with counter rotating water propellers are also known. These include inboard stern drives and lower units for outboard motors such as:
(a) U.S. Pat. No. 5,890,938 issued to Brunswick on Apr. 6, 1999, (b) U.S. Pat. No. 5,529,520 issued to Kaisha on Jun. 25, 1996, and (c) U.S. Pat. No. 5,558,498 issued to Kaisha on Sep. 24, 1996
However, the marine based prior art solutions also suffer from overly complex transmissions, specific hydrodynamic housings for application in a water environment, and multiple drive shafts (again, a solid drive shaft inside a hollow drive shaft). Assembly of these units is difficult and time consuming. This area of prior art is simply not adaptable to airboats for operating a pair of air propellers.
Therefore, there is a need for a drive system for counter rotating a pair of air propellers when an engine is mounted low in the hull of an airboat.
SUMMARY OF INVENTION
The present invention has many advantages. Mounting the engine low in the hull of the airboat provides a more stable airboat with a lower center of gravity. The drive system elevates the propellers to provide the proper clearance between the tips of the air propellers and the hull of the airboat. The amount of noise from a conventional belt drive is reduced. The modular design and simplified drive is easier to assemble and align. The second hollow drive shaft and the complexities associated with it are eliminated.
In one broad aspect of the present invention, a counter rotating air propeller drive system is provided. The counter rotating air propeller drive system includes a housing, a first drive, a second drive, and a third drive. The housing supporting the first drive in engaging relationship with the second drive. The housing also supporting the first drive in engaging relationship with the third drive. The third drive including an air propeller mount for receiving a first air propeller. The second drive coupled to an air propeller output drive shaft for receiving a second air propeller. In operation, the first drive operates the second drive in a first direction and the first drive operates the third drive in an opposite direction for counter rotating the air propeller mount and the air propeller output drive shaft.
In another broad aspect of the present invention, an airboat is provided. The airboat includes a hull, an engine disposed in the hull, an air rudder, and a counter rotating air propeller drive system. The counter rotating air propeller drive system includes a housing, a first drive, a second drive, and a third drive. The housing supporting the first drive in engaging relationship with the second drive. The housing also supporting the first drive in engaging relationship with the third drive. The third drive including an air propeller mount for receiving a first air propeller. The second drive coupled to an air propeller output drive shaft for receiving a second air propeller. In operation, the first drive operates the second drive in a first direction and the first drive operates the third drive in an opposite direction for counter rotating the air propeller mount and the air propeller output drive shaft.
The first drive includes a first housing member retaining the first drive in relationship with the second drive and the third drive.
The second drive includes a second housing member retaining the second drive in relationship with the first drive.
The third drive includes a third housing member retaining the third drive in relationship with the first drive.
The first drive is a first bevel gear, the second drive is a second bevel gear and the third drive is a third bevel gear. Teeth on the first bevel gear engage teeth on the second bevel gear. Teeth on the first bevel gear engage teeth on the third bevel gear for counter rotating the second bevel gear and the third bevel gear.
In an embodiment, the third drive includes a mount for receiving a first air propeller hub and the first air propeller is coupled to the first air propeller hub. Alternatively, the first air propeller is coupled directly to the third drive.
In an embodiment, the air propeller output drive shaft includes a mount for receiving a second air propeller hub and the second air propeller is coupled to the second air propeller hub. Alternatively, the second air propeller is coupled directly to the third drive.
Preferably, teeth on the first bevel gear engage teeth on the second bevel gear and teeth on the first bevel gear engage teeth on the third bevel gear for rotating the air propellers at the same speed. Alternatively, a first region of teeth on the first bevel gear engage teeth on the second bevel gear and a second region of teeth on the first bevel gear engage teeth on the third bevel gear for rotating the air propellers at differential speeds.
The drive system further includes a second housing, a fourth drive, a fifth drive, an interconnecting drive shaft, and a frame. The second housing supporting the fourth drive in engaging relationship with the fifth drive. The interconnecting drive shaft engaging the fourth drive and the interconnecting drive shaft engaging the first drive wherein rotating the fourth drive rotates the interconnecting drive shaft for rotating the first drive.
The fourth drive includes a fourth housing member retaining the fourth drive in relationship with the fifth drive.
The fifth drive includes a fifth housing member retaining the fifth drive in relationship with the fourth drive.
The fourth drive includes a fourth bevel gear. The fifth drive includes a fifth bevel gear. Teeth on the fourth bevel gear engage teeth on the fifth bevel gear for rotating in operation the interconnecting drive shaft.
The fifth bevel gear includes a mount for receiving an input drive shaft for rotating in operation the fifth drive.
BRIEF DESCRIPTION OF DRAWINGS
Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of an airboat and a counter rotating air propeller drive system,
FIG. 2 is a cross sectional side view of a drive system illustrating a transmission, interconnecting frame, and counter rotating air propeller drive,
FIG. 3 is a perspective view of the counter rotating air propeller drive,
FIG. 4 is a cross sectional side view of the counter rotating air propeller drive illustrating the first drive, second drive and third drive,
FIG. 5 is a cross sectional side view of the first drive,
FIG. 6 is a cross sectional side view of the second drive,
FIG. 7 is a cross sectional side view of the third drive,
FIG. 8 is a perspective view of the transmission,
FIG. 9 is a cross sectional side view of the transmission,
FIG. 10 is an exploded cross sectional side view of the transmission illustrating the fourth drive and fifth drive,
FIG. 11 is an end view of the drive system illustrating the transmission, interconnecting frame, and counter rotating air propeller drive, and
FIG. 12 is a cross sectional side view of a drive system illustrating an alternative embodiment of the interconnecting drive shaft.
DETAILED DESCRIPTION
The present invention is described in accordance with a preferred embodiment as illustrated with reference to FIG. 1 . An airboat is generally indicated at 10 . The airboat 10 is capable of operating on water, ice, and snow. The airboat 10 includes a hull 12 . An engine 14 is mounted low in the hull 12 of the airboat 10 to keep the center of gravity low. The engine 14 is connected through a drive shaft (not shown) to a drive system 16 (schematic representation). The drive system 16 includes a transmission, interconnecting frame, and counter rotating air propeller drive (see FIG. 2 ). A pair of air propellers 18 are connected to the counter rotating drive and in operation, the air propellers rotate in opposite directions to provide the necessary thrust to propel the airboat 10 forward. A pair of air rudders 20 are provided in order to maneuver the airboat 10 in operation by re-directing the flow of air to turn the airboat 10 either left or right. Those skilled in the art will appreciate the airboat 10 could be alternatively equipped with a single air rudder.
Referring now to FIG. 2 , the drive system of the present invention is further described. The engine 14 (only a diagrammatic portion is illustrated) is connected to the transmission 22 through a drive shaft 28 . The transmission 22 is mounted low in the hull 12 of the airboat 10 in alignment with the engine 14 . The counter rotating air propeller drive 26 is disposed above the transmission 22 by the interconnecting frame 24 at a suitable height to provide clearance for the air propellers 18 (not shown) with the hull of the airboat 10 . The transmission 22 and counter rotating air propeller drive 26 are connected through an interconnecting drive shaft 30 to transmit power from the transmission 22 to the counter rotating air propeller drive 26 . The transmission 22 and the counter rotating air propeller drive 26 are retained in operational alignment by the frame 24 .
Referring now to FIG. 12 , an alternative embodiment of the present invention is described with respect to the interconnecting drive shaft 30 . In this embodiment, the interconnecting drive shaft 30 includes a primary drive interconnect 290 , a primary universal joint 282 , a primary drive section 278 , a secondary drive section 286 and secondary drive interconnect 288 .
The primary drive interconnect 290 has a long splined shaft that interfaces to the fourth drive in the transmission 22 through the mount 184 (see FIG. 10 ) and is retained with the fourth drive. A primary universal joint 282 connects the primary drive interconnect 290 to the primary drive section 278 at one end. This provides a first flexible joint between the transmission 22 and the counter rotating air propeller drive 26 . The primary drive section 278 includes a long splined shaft at another end to interface with a secondary drive section 286 . The secondary drive section 286 has a complimentary splined mount for receiving the long splined shaft. The spines cooperate to rotate both members while permitting a vertically sliding joint between the primary drive section 278 and the secondary drive section 278 .
The secondary drive section 286 is connected to the secondary drive interconnect 288 by a secondary universal joint 280 . This provides a second flexible joint between the transmission 22 and the counter, rotating air propeller drive 26 . An end of the secondary drive interconnect 288 includes a long splined shaft that interfaces to the mount 94 of the first drive 36 in the counter rotating air propeller drive 26 .
The alternative embodiment of the interconnecting drive shaft 30 provides two flexible joints and one vertically sliding joint when mounting the counter rotating air propeller drive 26 at differing vertical and horizontal alignments from the transmission 22 while providing rotation movement of the interconnecting drive shaft 30 .
Referring now to FIG. 3 , the central housing 31 of the counter rotating air propeller drive 26 is described. The central housing 31 includes a bottom member 260 . The bottom member 260 has a mounting surface 264 and a central opening 262 . The central opening 262 and surface 264 receive for mounting the first drive 36 (not shown). A plurality of threaded bores 266 are provided in the bottom member 260 for securing and sealing the first drive 36 to the bottom member 260 by a plurality of fasteners, for example bolts.
The central housing 31 also includes a front member 268 . The front member 268 has a mounting surface 272 and a central opening 270 . The central opening 270 and surface 272 receive for mounting the second drive 38 (not shown). A plurality of threaded bores 274 are provided in the front member 268 for securing and sealing the second drive 28 to the front member 268 by a plurality of fasteners, for example bolts.
The central housing 31 also includes a back member 276 . The back member is substantially the same as the front member 268 (for example, the size of the central opening may be a different diameter, larger in the preferred embodiment). The back member has a mounting surface (not shown) and central opening (not shown). The third drive 40 is received for mounting by the surface and central opening of the back member 276 . A plurality of threaded bores (not shown) are provided in the back member 276 for securing the third drive 40 to the back member 276 by a plurality of fasteners, for example bolts.
The central housing 31 also includes a frame mount member 256 . The frame mount member 256 has a plurality of bores 258 . The frame mount member 256 and bores 258 are for mounting and securing the central housing 31 in the interconnecting frame 24 .
Referring now to FIG. 4 , a cross sectional view of the counter rotating air propeller drive 26 is further described. A first drive, generally indicated at 36 is illustrated mounted in the first opening 262 of the bottom member 260 as previously described.
A second drive, generally indicated at 38 is illustrated mounted in the second opening 270 of the front member 268 as previously described. The second drive 38 is connected to an air propeller output drive shaft 42 . Rotation of the second drive 38 causes rotation of the air propeller output drive shaft 42 . A second air propeller hub 68 is mounted on an end of the air propeller output drive shaft 42 for connecting a second air propeller (not shown) to the drive 26 .
A third drive, generally indicated at 40 , is illustrated mounted in the third opening of the back member 276 s previously described. In the preferred embodiment, a first air propeller hub 64 is mounted directly to the third drive 40 for connecting a first air propeller (not shown) to the drive 40 . Alternatively, a first air propeller may be mounted to the third drive 40 without an air propeller hub 64 .
The central housing 31 supports and retains the first drive 36 , the second drive 38 , and the third drive 40 in operational relationship such that rotation of the first drive 36 rotates the second drive 38 in one direction and the first drive 36 also operates the third drive 40 in an opposite direction for driving the counter rotating air propellers. The second drive 38 and the third drive 40 are retained in axial alignment about a lengthwise horizontal axis by the central housing 31 . This alignment is obtained by a inner surface of the second opening 270 in the front member 272 engaging a complimentary sidewall inner surface of the second housing member 48 , and a surface of the third opening (not shown) in the back member 276 engaging a complimentary sidewall surface of the third housing member 50 . The first drive 36 is retained about a substantially perpendicular vertical axis. A inner surface of the first opening 262 in the bottom member 260 engages a complimentary sidewall surface of the first housing member 46 provides alignment of the first drive.
Referring now to FIG. 5 , the first drive 36 of the counter rotating air, propeller drive 26 is further described.
The first drive 36 has a first housing member generally indicated as 46 . The first housing member 46 is a separate member from the central housing 31 . The first housing member 46 is formed by a main body with a central axial opening. A first cylindrical recess 96 is located in one end of the first housing member 46 for receiving a retainer 106 . Optionally, a seal may be provided between the retainer 106 and the cylindrical recess 96 . Persons skilled in the art understand a seal may be provided in other locations to keep a lubricant in the air propeller drive during operation. A second cylindrical recess 98 is formed in the first housing member 46 for receiving a bearing 84 . A third cylindrical recess 104 is formed in the first housing member 46 for receiving a second bearing 82 . A ledge 102 extends outwardly towards the central opening between the recesses ( 98 , 104 ) separating the second cylindrical recess 98 and the third cylindrical recess 104 . The ledge 102 provides support and a seat for the bearings ( 82 , 84 ). The first housing member 46 has an outwardly extending flange 100 with a plurality of spaced openings for receiving fasteners. The outwardly extending flange 100 engages a surface 264 (see FIG. 4 ) for sealing engagement with the housing 31 . A plurality of fasteners 86 secure and seal the first housing member 46 the central housing 31 . Optionally, a seal (“O” ring or gasket) may be provided between the first housing member 46 and the central housing 31 .
The first drive 36 also has a first bevel gear 52 . The first bevel gear 52 has a plurality of teeth 54 for engaging teeth of the second bevel gear (not shown) and teeth of the third bevel gear (not shown). One end of the first bevel gear 52 includes a smaller diameter cylindrical threaded portion for receiving a nut 90 . The other end of the first bevel gear 52 includes a surface for cooperating with a retainer 92 .
A mount 94 is provided to engage the first bevel gear 52 with the interconnecting drive shaft 30 . The mount 94 includes a toothed spline on one end of the interconnecting drive shaft 30 and a complimentary toothed spline on the inside surface of the central axial opening of the first bevel gear 52 . The central axial opening of the first bevel gear 52 extends the length of the first bevel gear 52 . Those skilled in the art will appreciate the mount 94 is not limited to toothed splines. Alternatively for example, a pair of slots and key could be used in the mount 94 . The mount 94 provides rotation of the first bevel gear 52 with the interconnecting drive shaft 30 in operation.
The first bevel gear 52 is secured to the interconnecting drive shaft 30 by the retainer 92 and a shoulder on an end of the interconnecting drive shaft 30 . While the retainer 92 is illustrated as a member with fasteners located on an end of the interconnecting drive shaft 30 , other retainers may be applied. For example, an end of the interconnecting drive shaft 30 may be threaded to receive a nut for securing the first bevel gear 52 to the interconnecting drive shaft 30 .
The first bevel gear 52 and the first housing member 46 are assembled to form the first drive 36 . The bearing 82 is placed, or pressed, into the cylindrical recess 104 until it bottoms out and seats on a surface of the flange 102 . The other bearing 84 is placed, or pressed, into the cylindrical recess 98 until it bottoms out and seats on an opposite surface of the flange 102 . A cylindrical shaft of the first bevel gear 52 is inserted into the openings of the bearings ( 82 , 84 ) until a ledge of the bevel gear 52 contacts a surface of the bearing 82 . This locates the first bevel gear 52 in the central opening of the first housing member 46 . The retainer 106 is placed over threaded cylindrical section on the first bevel gear 52 . The retainer 106 contacts a surface of the bearing 84 . A nut is placed on the threaded cylindrical section and tightened to retain the assembly in the first housing member 36 . A lock washer 88 keeps the nut tight.
Referring now to FIG. 6 , the second drive 38 of the counter rotating air propeller drive 26 is further described.
The second drive 38 has a second housing member generally indicated as 48 . The second housing member 48 is separate from the central housing 31 . The second housing member 48 is formed by a main body with a central opening. A first cylindrical recess 114 is located in one end of the second housing member 48 for receiving a retainer 130 . Optionally, a seal may be provided between the retainer 130 and the cylindrical recess 114 . Persons skilled in the art understand a seal may be provided in other locations to keep a lubricant in the air propeller drive during operation. A second cylindrical recess 116 is formed in the second housing member 48 for receiving a bearing 110 . A third cylindrical recess 120 is formed in the second housing member 48 for receiving a second bearing 108 . A ledge 118 extends outwardly towards the central axial opening of the second housing member 48 separating the second cylindrical recess 116 from the third cylindrical recess 120 . Opposite sides of the ledge 118 provide support and a seat for the bearings ( 110 , 108 ). The second housing member 48 has an outwardly extending flange 112 with a plurality of spaced openings for receiving fasteners. The outwardly extending flange 112 engages a surface 272 (see FIG. 7 ) for sealing engagement. A plurality of fasteners 86 secure and seal the second housing member 48 and the housing 31 . Optionally, a seal may be provided between the second housing member 48 and the housing 31 such as an “O” ring or gasket.
The second drive 38 also has a second bevel gear 56 . The second bevel gear 56 has a plurality of teeth 58 for engaging teeth of the first bevel gear 52 (not shown). One cylindrical end of the second bevel gear 56 includes threads for receiving a nut 126 .
A mount 122 is provided to engage the second bevel gear 56 with the air propeller drive shaft 42 . The mount 122 includes a toothed spline on one end of the air propeller drive shaft 42 and a complimentary toothed spline on the inside surface of the central axial opening of the second bevel gear 56 . The central axial opening extends the length of the second bevel gear 56 . Those skilled in the art will appreciate the mount 122 is not limited to toothed splines. Alternatively for example, a key could be used in the mount 122 . The mount 122 provides rotation of the second bevel gear 56 with the air propeller drive shaft 42 in operation.
The second bevel gear 56 is secured to the air propeller drive shaft 42 by the retainer 124 (illustrated as a nut and lock washer) and a shoulder on another end of the air propeller drive shaft 42 .
The second bevel gear 56 and the second housing member 48 are assembled to form the second drive 38 . The bearing 108 is placed, or pressed, into the cylindrical recess 120 until it bottoms out and seats on a surface of the ledge 118 . The other bearing 110 is placed, or pressed, into the cylindrical recess 116 until it bottoms out and seats on an opposite surface of the ledge 118 . A cylindrical shaft of the second bevel gear 56 is inserted into the central opening of the bearings ( 108 , 110 ) until a ledge of the second bevel gear 56 contacts a surface of the bearing 108 . This locates the second bevel gear 56 in the central opening of the second housing member 48 . The retainer 130 is placed over a cylindrical threaded section of smaller diameter on the second bevel gear 56 . The retainer 130 contacts a surface of the bearing 110 . A nut is placed on the treaded section and tightened to retain the assembly in the second housing member 48 . A lock washer 128 keeps the nut tight.
A bearing 132 is located intermediate on an outside surface of the air propeller drive shaft 42 . The bearing 132 provides support and permits rotational movement between the air propeller drive shaft 42 and the third drive 40 (not shown).
The air propeller shaft 42 includes a mount 66 for receiving an air propeller hub 68 . The mount 66 includes a toothed spline on one end of the air propeller shaft 42 and a complimentary toothed spline on an inside surface of a central axial opening in the air propeller hub 68 . The mount 66 provides rotation of the air propeller hub 68 with the air propeller shaft 42 .
An end of the air propeller shaft 42 includes threads 144 . The air propeller hub 68 is secured to the air propeller shaft 42 by the nut 142 and a shoulder on the air propeller shaft 42 . A lock washer 140 keeps the nut tight. The air propeller shaft 42 includes an outwardly extending flange 134 and a central hub 138 . An air propeller is centered and mounted over the central hub and secured to the flange 134 by a plurality of fasteners 136 , for example bolts.
Referring now to FIG. 7 , the third drive 40 of the counter rotating air propeller drive 26 is further described.
The third drive 40 has a third housing member 50 and a third bevel gear 60 . The third housing member 50 is separate from the central housing 31 . The third bevel gear 60 has teeth 62 for engaging complimentary teeth 54 on the first bevel gear 52 (see FIG. 5 ). A central axial opening 146 extends lengthwise through the third bevel gear 60 . The air propeller output drive shaft 42 extends through the central axial opening 146 (see FIG. 4 ). The bearing 132 engages an inner surface of the central opening 146 to support the air propeller output drive shaft 42 . The third bevel gear 60 has a substantially cylindrical section. A first diameter portion receives the bearings ( 156 , 158 ). A second smaller diameter portion includes the mount 44 for mounting the air propeller hub 64 . Alternatively, an air propeller (not shown) may be mounted directly to the mount 44 . In either embodiment, the air propeller is mounted to the third drive 40 by a drive shaftless connection. A third and smallest diameter portion includes threads for receiving the nut 172 .
The third housing member 50 has a cylindrical recess 148 , a ledge 152 , and another cylindrical recess 150 . The cylindrical recess 148 receives the bearing 156 and the other cylindrical recess 150 receives the bearing 158 . The ledge 152 ′ provides separation, support, and a seat for the bearings ( 156 , 158 ). Optionally, a seal 160 is mounted in the cylindrical recess 148 . Alternatively, a seal may be provided in other locations of the assembly. An outwardly extending flange 154 includes a plurality of spaced openings to receive fasteners 86 . The third drive 40 is mounted in an opening in the back member 276 and secured by the fasteners 86 . Optionally, a seal (“O” ring or gasket) is provided to seal the third drive 40 with the central housing 31 .
In a preferred embodiment, a mount 44 on the third bevel gear 60 receives the propeller hub 64 . The mount 44 includes a toothed spline on an end of the third bevel gear 60 and a complimentary toothed spline on an inner surface of a central axial opening on the first propeller hub member 162 . A washer 170 and the nut 172 secure the propeller hub member 162 on the third bevel gear 60 . A second propeller hub member 164 fits over the first propeller hub member 162 . The second propeller hub member 164 includes a central opening for passing the air propeller output drive shaft and a central hub 166 . The central hub 166 centers an air propeller (not shown) on the hub 166 . The air propeller and second propeller hub member 164 are secured to the first propeller hub member 162 by a plurality of fasteners 168 .
In assembly, the bearing 158 is placed or pressed into the cylindrical recess 150 until it seats on a surface of the ledge 152 . The other bearing 156 is placed or pressed into the cylindrical recess 148 until it seats on an opposite surface of the ledge 152 . The cylindrical section of the third bevel gear 60 is placed through the openings of the bearings ( 158 , 156 ) until a surface of the third bevel gear 60 contacts a surface of the bearing 158 . The seal 160 is optionally placed in the cylindrical recess 148 . The first propeller hub member 162 is placed over the third bevel gear 60 on the mount 44 until and end of the first propeller hub member 162 engages a surface of the bearing 156 . The washer 170 and nut 172 are placed on the threaded end of the third bevel gear 60 . The nut is tightened to retain the assembly with the third housing member 50 . The washer 170 keeps the nut 172 tight.
Referring now to FIGS. 4 , 5 , 6 , and 7 , the gear ratio between the first drive 36 and second drive 38 is preferably 1:1. The gear ratio between the first drive 36 and the third drive 40 is preferably 1:1. Those skilled in the art will appreciate that in the alternative, the two gear ratios may be different. For differing gear ratios, rotation of the first drive 36 causes rotation of the second drive 38 at one speed, and causes simultaneous rotation of the third drive 40 at a different speed providing differential speed between the pair of air propellers.
For example, the radius of the teeth 62 of the third bevel gear 60 could be different from the radius of the teeth 58 of the second bevel gear 56 . The teeth 54 of the first bevel gear 52 must be wide enough to engage the teeth 54 on a first region or portion of the teeth 54 , and to engage the teeth 58 on a second region or portion of the teeth 54 . This provides different gear ratios between the second and third drives.
Referring now to FIG. 8 , the second central housing 70 of the transmission is described. The second housing includes a top member 238 . The top member 238 has a mounting surface 242 and a central opening 244 . The central opening 244 and surface 242 receive for mounting the fourth drive 32 (not shown). A plurality of threaded bores 246 are provided in the top member 238 for securing and sealing the fourth drive 32 to the top member 238 by a plurality of fasteners, for example bolts.
The second housing also includes a front member 240 . The front member 240 has a mounting surface 248 and a central opening 250 . The central opening 250 and surface 248 receive for mounting the fifth drive 34 (not shown). A plurality of threaded bores 252 are provided in the front member 240 for securing and sealing the fifth drive 34 to the front member 240 by a plurality of fasteners for example bolts. The front member 240 also includes a plurality of threaded bores 254 for mounting the second central housing 70 to the interconnecting frame 24 by a plurality of fasteners, for example bolts.
Referring now to FIG. 9 , the transmission, generally indicated at 22 is described. The transmission 22 includes a second central housing 70 , a fourth drive 32 , and a fifth drive 34 . The second central housing 70 retains the fourth drive 32 and the fifth drive 34 in operational alignment. The fourth drive 32 is retained about a vertical axis and the fifth drive 34 is retained about a substantially perpendicular horizontal axis. The engine (not shown) is connected to the fifth drive 34 through the drive shaft 28 . The fifth drive 34 is connected to the fourth drive 32 which in turn is connected through the interconnecting drive shaft 30 to first drive 36 of the counter rotating air propeller drive 26 through the interconnecting drive shaft 30 . Rotation of the drive shaft 28 rotates the fifth drive 34 , which rotates the fourth drive 32 , which rotates the interconnecting drive shaft 30 . The gear ratio between the fifth drive 34 and the fourth drive 32 are 1:1, however, those skilled in the art will appreciate different gear ratios may be applied.
Referring now to FIG. 10 , the fourth drive 32 is further described as shown in the exploded view. The fourth drive 32 includes the fourth housing member 72 and the fourth bevel gear 76 . The fourth housing member 72 is separate from the second central housing 70 . The fourth bevel gear 76 includes teeth 182 for engaging complimentary teeth on the fifth bevel gear 78 . The fourth bevel gear 76 has a first cylindrical portion for receiving the bearings ( 186 , 188 ) and a second cylindrical portion with threads for receiving a nut 194 . A mount 184 is provided in the central axial opening of the fourth bevel gear 76 . The central axial opening extends the length of the fourth bevel gear 76 . The mount 184 includes a spline formed on the surface of the central opening and a spline formed on an end of the interconnecting drive shaft 30 . Those skilled in the art appreciate that the mount 184 could also be a pair of slots and key arrangement. The mount 184 is a floating mount that permits lengthwise movement of the interconnecting drive shaft 30 with the fourth bevel gear 76 . This permits a degree of height adjustment between the transmission 22 and the air propeller drive 26 .
The fourth housing member 72 includes a central axial opening, a first cylindrical recess 178 for receiving a bearing 186 , and a second cylindrical recess 174 for receiving another bearing 188 . An outwardly extending ledge 176 is formed between the recesses ( 178 , 174 ) and provides a positive stop and seat for the bearings ( 186 , 188 ). The nut 194 is tightened on the threads of the fourth bevel gear 76 with the retainer 196 to keep the fourth bevel gear 76 in the fourth housing member 72 . The washer 192 keeps the nut tight. Optionally, a seal is provided at an end of the fourth housing member 72 between the retainer and the cylindrical recess.
The fourth drive 32 is assembled by placing or pressing the bearing 186 into the cylindrical recess 178 of the fourth housing member 72 until it seats. Another bearing 188 is placed or pressed into the cylindrical recess 174 of the fourth housing member 72 until it seats. The fourth bevel gear 76 is placed into the central openings of the bearing ( 186 , 188 ). The retainer 196 , washer 192 and nut 194 are placed on the threaded end of the fourth bevel gear 76 . The nut 194 is tightened retaining the fourth bevel gear 76 with the fourth housing member 72 .
The fourth housing member 72 fits into an opening 244 of the top member 238 . The outwardly extending flange 180 includes a plurality of openings (not shown) and is secured and sealed by a plurality of fasteners (not shown). Optionally, a seal (“O” ring or gasket) is provided between the fourth housing member 72 and the second housing 70 .
Referring now to FIG. 10 , the fifth drive 34 is further described as shown in the exploded view. The fifth bevel gear 78 has a central axial opening for receiving the drive shaft 28 . A mount 200 is provided between the central axial opening of the fifth bevel gear 78 and the drive shaft 28 . The mount 200 is a spline on the surface of the central opening and a complimentary spline on the outer surface of the drive shaft 28 . Alternatively, the mount 200 could be a slot and key arrangement. The fifth bevel gear 78 includes a first cylindrical section for receiving the bearings ( 212 , 214 ), and a second threaded smaller diameter cylindrical section for receiving the nut 220 . Teeth 198 engage complimentary teeth 182 on the fourth bevel gear 76 . A retainer 202 secures the drive shaft 28 with the fifth bevel gear 78 . The retainer 202 is a chamfered washer and nut combination, however, other forms of a retainer 202 may be applied.
The fifth housing member 74 includes a first cylindrical recess 204 for receiving a bearing 214 , and a second cylindrical recess 208 for receiving a bearing 212 . The fifth housing member 74 is separate from the second central housing 70 . An outwardly extending ledge 206 separates, supports, and provides a seat for the bearings ( 212 , 214 ). In assembly, the bearing 214 is placed or pressed into the cylindrical recess 204 of the fifth housing member 74 until it seats on a surface of the ledge 206 . Another bearing 212 is placed or pressed into the cylindrical recess 208 of the fifth housing member 74 until it seats on an opposite surface of the ledge 206 . The cylindrical shaft of the fifth bevel gear 78 is inserted into the openings of the bearings ( 212 , 214 ). The retainer 216 , washer 218 , and nut 226 are placed over the threaded end of the fifth bevel gear 78 . The nut 220 is tightened to retain the fifth bevel gear 78 in the fifth housing member 74 .
The fifth housing member 74 mounts in an opening 250 of the front member 240 and rests in place on the outwardly extending flange 210 . The outwardly extending flange 210 includes a plurality of openings for receiving a plurality of fasteners 86 for securing and sealing the fifth housing member 74 . Optionally, a seal (“O” ring or gasket) is located between the fifth housing member 74 and the second housing 70 .
Referring now to FIGS. 2 and 11 , the interconnecting frame 24 is described. The interconnecting frame 24 includes an engine mount 222 for securing the interconnecting frame 24 to the back of the engine. Another frame mount 226 is provided to secure the interconnecting frame 24 to an inside surface of the hull 12 of the airboat. Another frame mount 228 is provided to secure the interconnecting frame 24 to the transom of the airboat 10 .
The interconnecting frame 24 has a number of upright members 230 connected to a number of horizontal members 232 that form a substantially rectangular box like structure. The box like structure is further strengthened by a number of diagonal members 234 . The interconnecting frame 24 may be welded together, or fastened together with fasteners such as nuts and bolts. Alternatively, the interconnecting frame 24 could be a cast or an enclosed structure. Alternatively, the interconnecting frame 24 could be part of the air propeller cage. The interconnecting frame 24 has a central vertical opening for receiving the interconnecting drive shaft 30 between the transmission 22 and the air propeller drive 26 .
The interconnecting frame 24 has a transmission mount 224 located at one end of the frame and a air propeller drive mount 236 located at another end of the frame. The transmission mount 224 and the air propeller drive mount 236 are located in the interconnecting frame 24 such that the first drive 36 and the fourth drive 32 are in alignment when connected by the interconnecting drive shaft 30 . The transmission 22 is secured to the transmission mount 224 by fasteners and the air propeller drive 26 is also secured to the air propeller drive mount 236 by fasteners. In the preferred embodiment, the transmission 22 is mounted to the interconnecting frame 24 . Alternatively, the transmission 22 may be mounted to an inside surface of the hull 12 of the airboat 10 .
It will, of course, be understood that the above description has been given by way of example only and that modifications in detail may be made within the scope of the present invention.
Nomenclature for the Figures:
10 —airboat
12 —hull
14 —engine
16 —drive system
18 —pair of air propellers
20 —air rudders
22 —transmission.
24 —interconnecting frame
26 —counter rotating air propeller drive
28 —drive shaft
30 —interconnecting drive shaft
31 —central housing
32 —fourth drive
34 —fifth drive
36 —first drive
38 —second drive
40 —third drive
42 —air propeller output drive shaft
44 —air propeller mount
46 —first housing member
48 —second housing member
50 —third housing member
52 —first bevel gear
54 —teeth
56 —second bevel gear
58 —teeth
60 —third bevel gear
62 —teeth
64 —air propeller hub
66 —mount
68 —second air propeller hub
70 —second central housing
72 —fourth housing member
74 —fifth housing member
76 —fourth bevel gear
78 —fifth bevel gear
80 —mount
82 —bearing
84 —bearing
86 —fastener
88 —washer
90 —nut
92 —retainer
94 —mount
96 —cylindrical recess
98 —cylindrical recess
100 —flange
102 —ledge
104 —cylindrical recess
106 —retainer
108 —bearing
110 —bearing
112 —flange
114 —cylindrical recess
116 —cylindrical recess
118 —ledge
120 —cylindrical recess
122 —mount
124 —retainer
126 —nut
128 —washer
130 —retainer
132 —bearing
134 —flange
136 —bolts
138 —hub
140 —washer
142 —nut
144 —threaded end
146 —central opening
148 —cylindrical recess
150 —cylindrical recess
152 —ledge
154 —flange
156 —bearing
158 —bearing
160 —seal
162 —first propeller hub member
164 —second propeller hub member
166 —mount
168 —fastener
170 —washer
172 —nut
174 —cylindrical recess
176 —ledge
178 —cylindrical recess
180 —flange
182 —teeth
184 —mount
186 —bearing
188 —bearing
190 —seal
192 —washer
194 —nut
196 —retainer
198 —teeth
200 —mount
202 —retainer
204 —cylindrical recess
206 —ledge
208 —cylindrical recess
210 —flange
212 —bearing
214 —bearing
216 —retainer
218 —washer
220 —nut
222 —engine mount member
224 —transmission mount
226 —hull frame mount
228 —transom frame mount
230 —upright members
232 —horizontal members
234 —diagonal members
236 —air propeller drive mount
238 —top member
240 —front member
242 —mounting surface
244 —central opening
246 —threaded bores
248 —mounting surface
250 —central opening
252 —threaded bores
254 —threaded bores
256 —mount member
258 —openings
260 —bottom member
262 —central opening
264 —mounting surface
266 —threaded bores
268 —front member
270 —central opening
272 —mounting surface
274 —threaded bores
276 —back member
278 —primary drive section
280 —secondary universal joint
282 —primary universal joint
284 —sliding joint
286 —secondary drive section
288 —secondary drive interconnect
290 —primary drive interconnect
|
An airboat and drive system for operating a pair of counter rotating air propellers that propel an airboat are described. An engine is mounted low in the hull of an airboat to lower the center of gravity and provide a more stable airboat. The drive system is connected to the engine through a drive shaft. The drive system includes a transmission, interconnecting frame, and counter rotating air propeller drive. The interconnecting frame mounts the counter rotating air propeller drive above the transmission providing proper clearance for the air propellers with the hull of the airboat. The transmission and counter rotating air propeller drive are connected through an interconnecting drive shaft. The amount of noise from a conventional belt drive is reduced. The modular design and simplified drive system is easier to assemble and align.
| 1
|
BACKGROUND OF THE INVENTION
a) Field of the Invention
This invention relates to a cam switch mechanism suitable for controlling automatic dishwashers, etc.
b) Description of the Related Art
Automatic dishwashers can automatically wash dishes, etc., by conducting processes such as wash, rinse, and heat, etc., for specific periods of time, according to the selected course. Cam switch mechanisms are built into these automatic dishwashers, and the execution of each process is controlled by making a plurality of cams, provided so as to correspond with the processes, turn together.
With the conventional cam switch mechanism, the automatic washing program is made to correspond from beginning to end with one cycle of each cam. In the cam surface of each cam, a protrusion is formed only in the region wherein, out of all the automatic washing programs, only the corresponding process is performed, and the proportion of the entire cam surface length occupied by this region corresponds to the shortness or length of the time that each process is performed. In other words, for processes that are performed over a long time period, the protrusion region is formed broadly, while, conversely, for processes that are completed in a short period of time, the region is formed narrowly. The turning speed of the cams is constant, and when the cams make one cycle, the automatic washing terminates.
With the conventional cam switch mechanism, when a short-duration process is set, the protrusion on the cam surface which performs the switching operation is small, resulting in poor timing precision when performing on-off operations. Not only that, but the small protrusions on the cam surface easily become worn over time, and precision deteriorates markedly even with a slight amount of wear.
On the other hand, in order to improve the timing precision of the on-off operations, it is well to perform the control directly by means of a computer instead of controlling by means of a cam switch mechanism. Computers, however, are weak electrical systems, requiring expensive power relays for them to directly control each process, resulting in higher production costs.
OBJECT AND SUMMARY OF THE INVENTION
The primary object of this invention is to provide a cam switch mechanism that can improve the timing precision of each process control, while holding down the rise in production costs.
In accordance with the invention, a cam switch mechanism comprises a drive source, a cam driven by the drive source, switching means responsive to contacting the cam surface of the cam for switching its electrically conducting state and a control unit for controlling the drive source. Control of the drive source by the control unit makes it possible to set positions of the cam as desired and permits the electrically conducting state of the switching means to be freely set.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a front elevation depicting one example of an embodiment for the cam switch mechanism to which this invention pertains;
FIG. 1a is a block diagram illustrating various features of an embodiment for the cam switch mechanism such as the control unit, motor, double ratchet, etc.;
FIG. 2 shows a plan view of the cam switch mechanism depicted in FIG. 1;
FIG. 3 illustrates a bottom view of the cam switch mechanism depicted in FIG. 1;
FIG. 4 illustrates a diagram that indicates the positioning of the gears in the cam switch mechanism depicted in FIG. 1;
FIG. 5 illustrates a cross-sectional view of the cam switch mechanism depicted in FIG. 1;
FIG. 6 presents a diagram which shows the timing with which the cams in the cam switch mechanism depicted in FIG. 1 turn the switching means on;
FIG. 7 presents a diagram which indicates the particulars of the modes for the automatic dishwasher into which the cam switch mechanism depicted in FIG. 1 is built;
FIG. 8 presents a diagram which indicates the operating order of the sequence switch(es) in the case where the cam switch mechanism depicted in FIG. 1 is built into an automatic dishwasher;
FIG. 9 presents a diagram which indicates the load timing of the sequence switches in the case where the cam switch mechanism depicted in FIG. 1 is built into an automatic dishwasher;
FIG. 10 illustrates a plan view which depicts the stop lever and detergent lever of an automatic dishwasher into which the cam switch mechanism depicted in FIG. 1 is built;
FIG. 11 shows a cross-sectional view that depicts the detergent deployment mechanism in an automatic dishwasher into which the cam switch mechanism depicted in FIG. 1 is built;
FIG. 12 shows a cross-sectional view which depicts another embodiment for the cam switch mechanism to which this invention pertains;
FIG. 13 shows a cross-sectional view of the cams in the cam switch mechanism depicted in FIG. 12;
FIG. 14 shows a plan view of the cam switch mechanism depicted in FIG. 12;
FIG. 15 illustrates a bottom view of the cam switch mechanism depicted in FIG. 12;
FIG. 16 shows a diagram that indicates the positioning of the gears in the cam switch mechanism depicted in FIG. 12; and
FIG. 17 presents a diagram which shows the timing with which the cams in the cam switch mechanism depicted in FIG. 12 turn the switching means on.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments of this invention will now be described in detail.
FIGS. 1-5 depict one embodiment of the cam switch mechanism to which this invention pertains. This cam switch mechanism 1, for example, is built into an automatic dishwasher; it comprises a motor 2 that is the drive source, cams 3-8 which are driven by the aforementioned motor 2 and have uneven parts (cam surfaces) of specified shapes, switching means 21-25 that slide against the uneven parts of aforementioned cams 3-8 and thereby switch on and off, and a control unit that controls the motor 2. The drive, stopping, and drive speed of the motor 2 are controlled by the aforementioned control unit to set freely the period of time during which the aforementioned switching means is turned on or off. The motor 2 is, for example, a stepping motor. Accordingly, the speeds at which the cams turn are variable, and they can be turned forward and backward.
The actions exhibited by an automatic dishwasher include a fill (hold water--FILL) action, a pump (spray water--PUMP) action, a drain (discharge water--DRAIN) action, and a heater (drying--HEATER) action. The cam switch mechanism 1 executes these actions, either individually or in combination.
The cams include, for example, three switch cams 3--5, one detergent cam (action cam) 6, and two home cams 7 and 8. The first switch cam 3 corresponds to the fill action and drain action of the automatic dishwasher. The second switch cam 4 corresponds to the pump action. The third switch cam 5 corresponds to the heater action. These three switch cams 3-5 are formed integrally together with the first home cam 7 and turn as one unit. The first home cam 7 detects the home position for each of the switch cams 3-5. Also, the detergent cam 6 controls the detergent deploying timing and the rinse deploying timing of the automatic dishwasher. The second home cam 8 detects the home position of the detergent cam 6.
These cams 3-8 are turned by the stepping motor 2. The turning of the stepping motor 2 is transmitted to a first clutch 9 and a second clutch 10 via a first gear 11, a second gear 12, a third gear 13, and a fourth gear 14. The two clutches 9 and 10 have pawls which convey the turning force only in constant and opposite directions, respectively.
The clutches 9 and 10 and the fourth gear 14 are combined on the same shaft to configure a double ratchet mechanism. When the stepping motor 2 is turned forward, the turning force thereof is transmitted to the first clutch 9, whereas when the stepping motor 2 is turned in reverse, this turning force is transmitted to the second clutch 10.
The turning of the first clutch 9 is transmitted to each of the switching cams 3-5 via the gear 15 and the gear 16. Meanwhile, the turning of the second clutch 10 is transmitted to the second home cam 8 via the gear 17 and the gear 18. This second home cam 8 and the detergent cam 6 are made into a single unit with a screw.
In other words, the cam switch mechanism 1 to which this invention pertains has a double ratchet mechanism, that is, a transmission switching means, between the motor 2 and the switch cams 3-5 and detergent cam 6. While separating the switch cams 3-5 and the detergent cam 6, the cam switch mechanism links one ratchet of the double ratchet mechanism to each of the switch cams 3-5, and the other ratchet to the detergent cam 6, respectively, turning the switch cams 3-5 when the motor turns forward, and turning the detergent cam 6 when the motor 2 turns in reverse.
Furthermore, the second gear 12 is formed integrally with the third gear 13, the first clutch 9 with the gear 15, and the second clutch 10 with the gear 17.
On the cam surfaces of the cams 3-8, the functions noted in FIG. 6 are allocated over the entire 360° cycle of the cam surfaces.
The switching means 21-25 are, for example, leaf switches which are turned on by the elastic deformation of a plate. Each of the switching means 21-25 is turned on by sliding against either a depression or protrusion in the cam surfaces of the switch cams 3-5 and the home cams 7 and 8, and are each turned off by sliding against the other.
Meanwhile, the detergent cam 6, as depicted in FIG. 10, controls the detergent deployment timing and the rinse deployment timing via action members, i.e. via a stop lever 19 and a detergent lever 20. The detergent lever 20 is spring-loaded in the counter- clockwise (CCW) direction.
More specifically, when due to the detergent wait state indicated by the solid lines in FIG. 10, the detergent cam 6 turns so that the arm 19a of the stop lever 19 drops to the drop position 6a of the cam 6, an engagement piece 121 in the stop lever 19 separates from an engagement piece 122 in the detergent lever 20; the detergent lever 20 turns in the CCW direction so that the arm 20a of the detergent lever 20 engages the engagement piece 121, thereby starting the rinse deployment wait state.
At this time, the detergent (not indicated in the drawings) is deployed. To explain the workings of detergent deployment with reference to FIG. 11, the detergent lever 20 turning shaft 26 and the detergent deployment hatch 27 are engaged. Now, when the detergent lever 20 reaches the position indicated in FIG. 10 by the double-dotted broken lines, the detergent deployment hatch 27 swings to open due to the turning of the turning shaft 26, and the detergent 28 is deployed.
Further, when the detergent cam 6 turns in the CCW direction, and the arm 19a of the stop lever 19 drops to the rinse drop position 6b of the cam 6, the engagement between the engagement piece 121 of the stop lever 19 and the stopper 125 of the detergent lever 20 is broken, the detergent lever 20 turns in the CCW direction, the arm 20b of the detergent lever 20 pushes a rinse lever 123 to the stopper 124 of, and rinse deployment ensues.
After rinse deployment, the detergent cam 6 turns further in the CCW direction, reaching the state where it is stopped in the home position. When the dishwasher is used the next time, from this state, the detergent lever 20 is turned in the CW direction manually and the mechanism is reset.
Here, innovative measures are implemented so that there is no contact between either the engagement piece 121 and engagement piece 122, or the engagement piece 121 and stopper 125, when the detergent lever 20 is turned in the CW direction.
More specifically, when the detergent lever 20 is turned in the CW direction, the stop lever 19 is in the solid-line position in FIG. 10, so that the stopper 125 passes outside the engagement piece 121. Also, since the righthand end 22a of the engagement piece 122 has a gradually sloping shape, when the detergent lever 20 is manually turned in the CW direction, the engagement piece 121 gently rides over the end 22a, so that the detergent lever 20 turns smoothly, without letting the engagement pieces 121 and 122 collide.
FIG. 6 indicates the positioning of the cam surfaces in the cams 3-8, the functions corresponding to each cam surface combination, and the timing of wash and rinse deployment.
HOME indicates that the cam 7 is in the home position, with the switching means 24 in the turned-on state. FILL is the function of filling up with water, with the switching means 21 in the turned-on state due to the cam 3. FILL+PUMP is the function whereby water is sprayed while filling with water, with the state in which the switching means 22 is turned on by the cam 4 added to the FILL function. PUMP is the function which performs only water spraying, continuing the ON state of the switching means 22. With HEATER+PUMP, the state in which the switching means 23 is turned on by the cam 5 is added to the PUMP function, so it is the function which sprays water while heating. With DRAIN+PUMP, the state in which the switching means 21 touches the reverse contact due to the cam 3 is added to the PUMP function, so it is the function which sprays while discharging water. HEATER is the function which performs drying by heating, with the switching means 23 in the turned-on state due to the cam 5.
Moreover, the FILL and DRAIN functions are set so that, if the switching means 21 contacts the protrusion in the cam 3 and touches the contact on one side to turn on, the FILL function is activated, and if the switching means 21 contacts the depression in the cam 3 and touches the contact on the other side to turn on, the DRAIN function is activated, whereas when the switching means 21 is between the two contacts, both of these functions are turned off. However, to facilitate ease of explanation, the representation in FIG. 6 is divided between FILL and DRAIN.
The turning of the motor 2 is controlled by a control unit (not shown in the drawings) such as a microcomputer. The control unit varies the turning, stopping, and turning speed of the motor 2, and freely sets the times during which the switching means 21-25 are turned on and turned off, respectively. This control unit also doubles as the control unit for the automatic dishwasher.
We next describe the action of the cam switch mechanism 1 when it is built into an automatic dishwasher, referring to FIGS. 7-9.
Into the control unit of the automatic dishwasher, that is, into the control unit of the cam switch mechanism, five different wash modes are programmed, as indicated in FIG. 7. The user selects the wash mode according to his or her objective. For example, when hot scrubber is selected, processes are executed in the order pre-wash process→wash process→rinse process→heater process. All of these processes are done in 107 minutes.
Now, the pre-wash process is conducted in three cycles, of 4 minutes, 4 minutes, and 5 minutes duration, respectively.
During these cycles of the pre-wash process, as indicated in the lefthand column A in FIG. 8, the stepping motor 2 is turned forward to perform the functions (1) then (2) then (3) then (4) then (6).
Each function is diagrammed in FIG. 9. Function (1), for example, is the HOME function, wherein the first home cam 7 turns the switching means 24 on. Function (3), moreover, is the FILL+PUMP function, wherein the first switch cam 3 turns the switching means 21 on, and the second switch cam 4 turns the switching means 22 on. The control unit controls the turning of the motor 2. More specifically, it performs each function for the pre-set time while stopping and restarting the turning of the motor 2 and varying its turning speed. Any explanation of other functions are omitted here.
Meanwhile, the wash process is performed in 43 minutes. The wash process, as shown in the lefthand column A in FIG. 8, turns the stepping motor 2 forward and performs the functions (2) then (3) then (4) then (6), and also turns the stepping motor 2 in reverse to turn the detergent cam and perform detergent deployment D.
The automatic dishwasher performs the other processes in the same manner and completes the washing program. The automatic dishwasher washes dishes, etc., automatically, performing the various processes in a designated order, corresponding, respectively, to the selected wash mode.
With the cam switch mechanism 1 configured as in this embodiment, the switch cams 3-5 and the detergent cam 6 are separate entities, with each cam engaged in one cam of a double ratchet.
Accordingly, when, for example, the motor 2 turns CW, only the detergent cam 6 turns; when the motor 2 turns CCW, only the switch cams 3-5 turn. By being configured in this way, it is possible to turn only the detergent cam without returning the switch cams 3-5, making it possible to prevent pump start-up noise, etc., that is produced when the switch cams 3-5 are turned backward. In other words, there is no need to return the switch cams 3-5, so there is no generation of pump start-up noise, etc.
Also, with the portion of the surface of the cams which do not affect the on/off of the switching means 21-25, or, in other words, with the portion where the switching state (on/off state) of the switching means 21-25 is not switched, the motor 2 can be stopped. Furthermore, the detergent cam 6 is set exclusively for detergent deployment (140° position) and rinse deployment (200° position). As indicated in FIG. 8, in actuality, the switching means perform detergent and rinse deployment during (FILL+PUMP).
Moreover, the morphology described in the foregoing is one example of a morphology well suited to this invention, but the invention is not limited to this; various modified embodiments are possible within a range wherein the essence of this invention is not lost.
For example, in the foregoing description, a stepping motor 2 is employed as the drive source, but this is not necessarily limited to a stepping motor. It could also be a DC motor, for example. Or, for the case of switch actions only, it could even be an AC motor.
Also, the mechanism which transmits the turning of the stepping motor 2 to each cam is not limited to that described above. For example, as with the cam switch mechanism 30 depicted in FIGS. 12-16, the turning of the stepping motor 2 could also be transmitted to the cams 35-39 via a first gear 31→a second gear 32→a third gear 33→a fourth gear 34.
In this case, the switch cams 35-37 and the home cam 38 are formed integrally, and these cams 35-38 are formed into a single unit with the detergent cam 39 by means of a screw. In other words, with this embodiment morphology, all of the cams 35-39 turn as a single unit, so one home cam suffices.
Furthermore, the first switch cam 35 corresponds to the FILL action and DRAIN action of the automatic dishwasher. Also, the second switch cam 36 corresponds to the PUMP action. The third switch cam 37 corresponds to the HEATER action. The home cam 38 detects the home position of these cams. In addition, the detergent cam 39 controls the detergent deployment timing and the rinse deployment timing.
The cams 35-38 turn the corresponding switching means 40-43, respectively, on and off with the timing diagrammed in FIG. 17. Accordingly, even when structured in this manner, it is possible to automatically wash the dishes according to the wash mode selected, as indicated in FIG. 7, just as with the cam switch mechanism 1 described earlier. Moreover, the particulars of the processes when the cam switch mechanism 30 is employed are indicated in column B in FIG. 8. In this case, by turning the stepping motor 2 in reverse, it is possible to repeatedly perform functions already performed, or to pass over unnecessary functions without performing them.
More particularly, the various function regions are allocated to the region in the switch cams 35-37 from 0° to 122.5°. Also, the detergent cam 39 turns integrally with the switch cams 35-37, so that detergent deployment is performed when the detergent cam 39 is at 185°, and rinse deployment is performed when it is at 225°.
In the cam surfaces, the gradient is steep in the portions which connect the depressions with the protrusions, so that, in some cases, we cannot expect stable switching even when the switch makes contact. Even in such cases, however, with the cam switch mechanism of this invention, it is possible to control the electric current conducted to the switching means independently by a control means. Therefore, when a switching means contacts an unstable cam surface, the electric current can be cut off by the control means, so that stable switching can be performed such that unstable steep-gradient cam surfaces are not used.
Also, if control is effected with a specific cam surface so that no electric current goes to a switching means, it is possible to make the cams turn at high speed and pass over unnecessary functions without executing them, or to make the cams turn backward and execute the next function without executing unwanted functions.
As described in the foregoing, because the turning speed and turning direction of the cams are controlled by a control unit, and because the time during which the switching means are turned on and/or off can be set freely, it is possible to switch the switching means while turning the cams at high speed; on the other hand, it is possible, in cases where the switching means are not switched, to turn the cams at slow speed or to stop them. As a result, the long regions in the cam surfaces can be used to operate the switching means, thus improving the timing precision of the operational control of the switching means. Also, it is possible to operate the switching means using the cams, and to perform high-precision control without using the power relays that are necessary with conventional high-precision control, so that rising costs can be checked.
While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the true spirit and scope of the present invention.
|
A cam switch mechanism comprises a drive source, such as a motor, a cam driven by the drive source, a switching device responsive to contacting the cam surface of the cam for switching its electrically conducting state and a control unit, such as a microcomputer, for controlling the drive source. Control of the drive source by the control unit makes it possible to set positions of the cam as desired and permits the electrically conducting state of the switching means to be freely set. The control unit controls the drive direction, stopping and drive speed of the drive source.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application Ser. No. 61/027,884, filed on Feb. 12, 2008, the contents of which are herein incorporated by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to hose mounted indicators, and particularly, to visual indicator devices for enhancing firefighter safety.
BACKGROUND OF THE INVENTION
Firefighting is an inherently dangerous occupation, particularly when firefighting efforts require entrance into a burning building or other enclosed structure. In addition to the flames and attendant heat, the large quantities of unvented smoke can quickly reduce visibility to inches. Under such conditions it is easy for firefighters to become disoriented. The fire hose serves as a critical lifeline for firefighters, both for its ability to combat the fire and as a guide to help firefighters reliably find their way to the fire or to safety.
Under real fire conditions, firefighters can lose hold of the fire hose, either by accident or to accomplish some other mission. To find the fire hose again in the smoke and confusion of a fire, it is often necessary for firefighters to crawl on the floor and seek out the hose with their hands. Once regained, it can be difficult, if not impossible, for the firefighter to determine which direction to follow the hose to safety outside the building, or else to the nozzle, if necessary. This difficulty is greatly increased where multiple hoses are employed and firefighters often encounter a tangled mess of hoses. Unfortunately, several tragedies have resulted when firefighters have needed to leave a building but could not, in the stress and confusion of a fire, successfully follow a hose to safety.
One example of an attempt to facilitate a firefighter's ability to follow a fire hose to safety can be found in U.S. Patent Application Publication No. 2007/00663512. In the '512 publication, a collar with tactile directional indicating shapes is fitted into hose couplings. With the heavy gloves that firefighters must typically don for safety, properly identifying tactile indicators is difficult. In one embodiment, reflective or luminescent coatings are applied on outer surfaces of the collar. However, to be effective, reflective coatings require that a firefighter have an operable flashlight, and, in conditions of extremely reduced visibility, as are common in building fires, luminescent coatings can have very limited usefulness. Moreover, many luminescent coatings require prior exposure to light for activation. Under many conditions, for instance during nighttime firefighting, adequate prior exposure may not be feasible.
Another example of an attempt to facilitate a firefighter's ability to follow a fire hose to safety can be found in U.S. Pat. No. 6,257,750. In the '750 patent, a light emitting element is provided along the exterior surface of a fire hose. The various light emitting elements of the '750 patent extend along the entire length of the hose, in the form of a strip or string woven into, or otherwise affixed to, the exterior surface. The incorporation of such strips or strings of light emitting elements requires either a specially fabricated hose, or substantial modification to the entire length of an existing hose. Subsequently, the costs of implementing the '750 patent can be prohibitively high, particularly for a fire department with a limited budget. Moreover, these costs can be expected to recur each time a hose must be replaced.
SUMMARY OF THE INVENTION
From the foregoing, it will be appreciated that there is a need for a hose mounted indicator device that provides visual indications to firefighters and others and does not require a specially fabricated, or substantially modified, hose. Accordingly, it is the object of the present invention to provide a visual indicating device that can be easily retrofitted onto an existing fire hose, and can be easily transferred to a new fire hose. It is another object of the present invention to provide a visual indicating device that can be automatically activated by pressurization of a fire hose.
According to an embodiment of the present invention, a visual indicating device for mounting on a hose includes a substantially annular body having an outer wall and defining a central passage extending axially through the body between a first end and a second end, a plurality of lights arranged around the annular body so as to be visible from beyond the outer wall, a power source arranged within the annular body, and a switch for selectively energizing the plurality of lights from the power source.
According to another embodiment of the present invention, a fire hose assembly includes at least one length of hose, and at least one visual indicating device associated with the at least one length of hose.
According to an aspect of the present invention, the at least one visual indicating device is slidably disposed over the at least one length of hose. According to another aspect of the present invention, the at least one visual indicating device is associated with a coupling on an end of the at least one length of hose.
According to a further aspect of the present invention, the hose assembly includes a plurality of lengths of hose with a nozzle arranged on a terminal end of the lengths. A plurality of visual indicating devices are associated with the lengths. Each of the visual indicating devices includes a first group of lights and second group of lights, the first group of lights being closer to the nozzle than the second group of lights.
According to a method aspect of the present invention, a plurality of visual indicating devices are connected to an existing fire hose. The fire hose is pressurized to activate the plurality of visual indicating devices.
These and other objects, aspects and advantages of the present invention will be better understood in view of the drawings and following detailed description of preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is schematic view of a fire hose 10 equipped with a plurality of visual indicating devices, according to an embodiment of the present invention;
FIG. 2 is a perspective view of one of the visual indicating devices of FIG. 1 , with hidden components shown in broken lines;
FIG. 3 is a partially exploded view of the visual indicating device of FIG. 2 , with certain hidden components shown in broken lines;
FIG. 4 is a side view of one of the components of FIG. 3 ;
FIG. 5 is a side view of the visual indicating device of FIG. 2 , with certain components removed to show details and certain hidden components shown in broken lines;
FIG. 6 is a schematic view of certain electrical and electronic components of the visual indicating device of FIG. 2 ;
FIG. 7 is a perspective view of a visual indicating device integrated into a coupling, according to another embodiment of the present invention, with hidden components shown in broken lines;
FIG. 8 is a perspective view of a visual indicating device interposed into a coupling, according to an additional embodiment of the present invention, with hidden components shown in broken lines; and
FIG. 9 is a schematic view of a feeder line equipped with a plurality of visual indicating devices, according to a further embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1 , a fire hose 10 is equipped with a plurality of visual indicating devices 12 , according to an embodiment of the present invention. The devices 12 encircle the hose 10 at regular intervals. Referring to FIGS. 2 and 3 , each indicating device 12 includes an annular body 14 with an inner wall 16 defining a central passage 18 extending through the body 14 . A push switch 20 extends into the central passage 18 through the inner wall 16 .
The annular body 14 also has an outer wall 24 with a central portion 26 , a first end portion 28 and a second end portion 30 . The central portion 26 extends substantially in parallel with the inner wall 16 . The first and second end portions 28 , 30 slope inwards from the central portion 26 toward annular end surfaces 32 . The annular end surfaces 32 are substantially perpendicular to the inner wall 16 and each end surface 32 extends between respective ends of the inner wall 16 and end portions of the outer wall 24 .
A plurality of recesses 34 extend into the annular body 14 from the outer wall 24 . A light emitting diode (LED) 36 is arranged in each recess 34 . A clear transparent cover 38 is arranged over each of the recesses 34 and LEDs 36 in the central portion 26 . A red transparent cover 40 is arranged over each of the recesses 34 and LEDs 36 in the first end portion 28 . A green transparent cover 42 is arranged over each of the recesses 34 and LEDs 36 in the second end portion 30 . The covers 40 , 42 are arrow shaped and point away from the central portion 26 towards respective annular end surfaces 32 . The covers 38 - 42 each form a watertight seal for their respective recesses 34 .
Referring to FIG. 3 , under the central portion 26 of the outer wall 24 , the body 14 includes removable segments 50 . The removable segments 50 are semi-circular and are secured in place in the body 14 by being secured to each other. The removable segments 50 are secured to each other by threaded fasteners 52 inserted through oblique openings 54 in the removable segments 50 and into respective threaded bores 56 .
Gaskets 60 are arranged under the removable segments 50 to form a watertight seal. Referring to FIG. 4 , each gasket 60 defines open areas 62 through which electrical connections are made inside the body 14 . Between open areas 62 , each gasket 60 includes a solid area 64 corresponding to a junction between removable segments 50 .
Referring to FIGS. 3 and 5 , a space 70 is defined in the interior of the body 14 inside of the removable segments 50 . Batteries 72 and control electronics 74 are arranged in the space 70 . The recesses 34 communicate with the space 70 , allowing connections to be made between the batteries 72 , the control electronics 74 and the LEDs 36 . The control electronics 74 are arranged on a small printed circuit board 76 . The switch 20 is also connected to the printed circuit board 76 . An O-ring 78 surrounds the switch 20 and forms a watertight seal where the switch 20 extends out of the inner wall 16 into the central passage 18 .
Referring to FIG. 6 , the switch 20 and the batteries 72 are electrically connected to the control electronics 74 . Additionally, an alternate connection exists between the batteries 72 and the control electronics 74 , allowing the switch 20 to be bypassed. The LEDs 36 are powered by the batteries 72 through the control electronics 74 . The control electronics 74 include a transmitter/receiver (TX/RX) 80 , a timer 82 , a programmable logic controller (PLC) 84 , and a battery charge detector 86 . A remote device 88 can receive signals from and transmit signals to the control electronics 74 .
Referring to FIGS. 1-6 , in operation, a plurality of visual indicating devices 12 are arranged around the hose 10 at periodic intervals. The devices 12 are slid over the hose 10 when the hose 10 is in a depressurized state, as represented by broken line 90 in FIG. 3 . Each device 12 is placed around the hose 10 so that the red covers 40 will point to the nozzle end of the hose 10 , indicating the direction of the fire when the hose 10 is employed in firefighting. The green covers 42 will then indicate the direction of safety when the hose 10 is employed in firefighting. “Safety” as used herein, generally refers to the end of a hose that is opposite the end with the nozzle.
When the hose 10 is pressurized, as represented by broken line 92 in FIG. 3 , the hose 10 will expand to fill the central passage 18 and press against the inner wall 16 . Expansion of the hose 10 will result in depression of the switch 20 , signaling the control electronics 74 to energize the LEDs 36 . Alternately, the remote device 88 can be used to communicate with the TX/RX 80 to signal the control electronics 74 to energize the LEDs 36 . The LEDs 36 under the clear covers 38 are preferably the brightest and facilitate initial location of the hose 10 . Once the hose 10 is located, the LEDs under red and green covers 38 are used to find the nozzle of the hose 10 , or to reach safety outside, respectively.
If the LEDs 36 are energized based on depression of the switch 20 , upon subsequent release of the switch 20 , indicating possible depressurization of the hose 10 , the PLC 84 will start the timer 82 . The control electronics 74 will continue to energize the LEDs 36 until the timer 82 counts to a predetermined time, ensuring the LEDs 36 are not de-energized immediately due to an inadvertent depressurization of hose 10 . The predetermined time should be of sufficient duration to allow any firefighters to exit the building, and is adjustable using the PLC 84 based on the particular employment of the device 12 . The PLC 84 will also direct the TX/RX 80 to communicate the possible depressurization to the remote device 88 . If desired, the LEDs 36 can be de-energized at any time after hose 10 depressurization using the remote device 88 .
The charge detector 86 monitors the state of charge of the batteries 72 . If battery 72 charge drops below a predetermined threshold, the PLC 84 directs the TX/RX 80 to communicate with the remote device 88 , indicating a low state of charge for the corresponding device 12 . Additionally, during initial pressurization of the hose 10 , or during a battery test routine, the PLC 84 can indicate a low state of charge for the corresponding device 12 by having the control electronics 74 flashing the LEDs 36 in a predetermined “low battery” pattern.
In addition to the predetermined pattern indicating a low battery/battery test routine, the PLC 84 is programmed with additional predetermined patterns that can be activated by communication from the remote device 88 . The additional predetermined patterns include an “advance hose” pattern, a “withdraw hose” pattern, and an “evacuate” pattern. Using the remote device 88 , the hose 10 equipped with devices 12 can serve as an additional channel of communication to firefighters working within a burning building.
To conserve battery 72 charge, each firefighter can be equipped with a radio-frequency identification device (RFID) device 94 recognizable by the TX/RX 80 of the control electronics 74 of each device 12 when the RFID device 94 is within a predetermined range of the device 12 . When no RFID device 96 is within the predetermined range of a given device 12 , the PLC 84 will operate the LEDs 36 at a reduced power level. When a RFID device 94 comes within the predetermined range, the PLC 84 will operate the LEDs 36 at a maximum power level to enhance detectability. Additionally, the PLC 84 directs the TX/RX 80 to communicate with the remote device 88 to indicate that a RFID device 94 is in the vicinity of the device 12 .
The PLC 84 of each device 12 is configurable to direct the TX/RX to transmit a signal that allows the remote device 88 to identify which device 12 is the source of the transmission. In this way, the remote device 88 can identify and display information about individual devices 12 . For example, when receiving communications about hose depressurization, the remote device 88 indicates which hose is depressurized. Similarly, when receiving communications about low battery charge, the remote device 88 indicates which device 12 requires fresh batteries. Likewise, when receiving communications about vicinity of RFID devices 94 , the remote device 88 can be used to help determine the location of the firefighter wearing the RFID device 94 .
Referring to FIG. 7 , in another embodiment of the invention, a fire hose 110 is equipped with a visual indicating device 112 integrated into a hose coupling 114 . The device 112 functions substantially similarly to the device 12 , as described above, except that the device 112 includes a switch 120 communicating with control electronics 74 , rather than the push switch 20 . The switch 120 is closed when the coupling 114 is made, resulting the energization of LEDs. The control electronics 74 maintain the LEDs energized for a predetermined time after de-coupling, in a similar manner to that described above in connection with hose 10 depressurization.
Referring to FIG. 8 , in an additional embodiment of the invention, a fire hose 210 is equipped with a visual indicating device 212 adapted to be interposed into hose coupling 214 . The device 212 includes female and male threaded portions 222 , 244 that enable the device 212 to be connected between male and female threaded portions 246 , 248 of the coupling 214 . The device 212 functions substantially similarly to the device 12 , as described above, except that the device 212 includes a switch 220 that is closed by water pressure acting directly on the switch 220 , rather than indirectly through the hose 210 .
Referring to FIG. 9 , in a further embodiment of the invention, a feeder line 310 is equipped with a plurality of devices 312 . Devices 312 are similar in construction to devices 12 , 112 and 212 , as described above, but are equipped with flashing red lights to warn approaching motorists of the presence of the feeder line 310 in the road. Accordingly, the risk of a motorist driving over the feeder line 310 and risking damage to feeder line 310 , or inadvertent depressurization downstream of feeder line 310 , is reduced.
The present invention is not limited to the embodiments shown in the drawings and described above. Rather, those skilled in the art will appreciate that numerous modifications and adaptations to particular circumstances will fall within the scope of the present invention.
For instance, while the shape of the body 14 of the device 12 has been found to be advantageous for readily accommodating the LEDs 36 in recesses on the portions 26 - 30 , the present invention is not necessarily limited to such a shape. For example, bodies with no sloping end portions or non-annular bodies could all be employed. Also, bodies without the removable segments 50 , or with different removable segments, could be employed. The body is not necessarily limited to particular dimensions, and can be adapted for any fire hose or related component design.
Also, the present invention is not necessarily limited to a particular type or design of switch 20 or 120 , although these types of switches have been found advantageous. For example, contact switches, capacitance switches, magnetic switches and the like can also be employed. Likewise, combinations of switches can be employed or switches can be omitted altogether.
Additionally, the present invention is not necessarily limited to the use of LEDs as light sources, or to particular numbers or configurations of light sources. Lights or LEDs of other colors than those described herein may be employed. Covers of other shapes can also be used, such as triangles, fingers or stylized flames. Rather than colored covers, clear covers with colored LEDs can be used. Also, covers incorporating lenses for focusing the light can be used, as well as parabolic reflectors underneath the light sources. Alternately, the covers can be omitted and seals could be provided within the body 14 to provide a watertight barrier. Generally, a light adapted to display a particular color of light can include either a light that directly emits that color of light or a light that is equipped with a cover of the corresponding color.
Furthermore, seals of other designs, shapes, or types other than the seals 60 could also be employed, or the seals 60 could be omitted. For example, extremely high manufacturing tolerances could be relied on to prevent the introduction of moisture. Alternately, coated electronic components and connections could be employed to avoid short circuits even if moisture entered the body 14 .
Moreover, the present invention is not necessarily limited to any particular type or sophistication of control electronics 74 , or to the use of the printed circuit board 76 to hold the control electronics 74 . Also, the control electronics 74 could be omitted altogether. For example, the switch 20 could directly control energization of the light sources or LEDs without control electronics. Additionally, the remote device 88 could be omitted.
Also, the present invention is not necessarily limited any particular device or means for permitting discrete identification of each device 12 by the remote device 88 . For example, jumpers or dipswitches could be used to manually set a particular transmission frequency, or a particular transmission encoding, for each TX/RX 80 . Alternately, each PLC 84 could be configurable to operate the TX/RX 80 so as to result in a uniquely identifiable signal.
Additionally, the present invention is not necessarily limited to the integration of a visual indicating device 112 into any particular type of coupling or other component. For example, a visual indicating device can be integrated into other coupling designs, adapters, nozzles, and the like.
The foregoing is not an exclusive list of modifications and adaptations falling within the scope of the present invention. Instead, those skilled in the art will appreciate that these and other modifications and adaptations will fall within the scope of the invention as herein shown and described, and of the appended claims.
|
A visual indicating device for mounting on a hose includes a body having an outer wall and defining a central passage extending axially through the body between a first end and a second end, and a plurality of lights arranged around the annular body so as to be visible from beyond the outer wall. A power source is arranged within the annular body, and a switch selectively energizes the plurality of lights from the power source. The visual indicating device includes groups of differing colored lights. Mounted on a hose, one of the groups indicates the general direction of the nozzle and another of the groups indicates the general direction of an exit. The switch automatically energizes the lights upon pressurization of the hose.
| 5
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] This invention pertains to a novel method of performing an injection by a doctor, nurse and other health practitioner. More particularly, the invention pertains to a method for delivering an injection wherein the needle of the injection apparatus is simultaneously rotated and translated to reduce pain in the patient and to eliminate undesirable needle deflections.
[0003] 2. Description of the Prior Art
[0004] The notion that a hollow core needle could be used to inject a local anesthetic solution into the body was unknown until the late 1800's. When an American surgeon Dr. William Halstead demonstrated that an interstitial injection of aqueous cocaine resulted in an effective inferior alveolar nerve block he ushered in a new era of local pain management for both dentistry and medicine. Since that time, numerous improvements in the safety and efficacy of local anesthesia have evolved. The majority of these advancements have been related to the pharmacology and formulation of anesthetic agents making local pain control safer and more effective. In contrast, improvements to the drug delivery device (i.e. hypodermic syringe) have been few. The introduction of the manual aspirating syringe used in dentistry today has actually made the instrument less ergonomic for the operator to use than the non-aspirating version. Much advancement has been made in needle design over the past century. The development of a disposable needle had a major impact on all syringe injections because it insured sterility as well as consistent sharpness. Further advancements in metallurgy, surface treatments and manufacturing techniques have resulted in modern needles of unparalleled sharpness. Presumably, a sharper needle penetrates body tissues more easily thus resulting in less discomfort for the patient.
[0005] The use of a hypodermic needle in dentistry (as well as other medical fields) has been consistently shown to produce a deflection if an eccentric pointed cylindrical hypodermic needle is used( See Aldous J. Needle Deflection: a factor in the administration of local anesthetics. JADA 1968;77:602-04. Robinson SF, Mayhew, Cowan RD, Hawley RJ. Comparative study of deflection characteristics and fragility of 25-, 27-, and 30-gauge dentalneedls. JADA 1984;109:920-24.).
[0006] Successful local anesthesia is critical to the daily practice of dentistry. It is a prerequisite to insure maximum patient comfort while performing a wide variety of clinical procedures on the hard and soft tissues of the oral cavity. Therefore, achieving predictable results in local anesthesia is of great importance to all clinicians. Failure to do so can lead to increased stress for both the operator and the patient. An injection that is recognized as one of the more difficult in dentistry is the inferior alveolar (IA) nerve block. There are a number of physical factors that have been associated with the relative success or failure of the IA nerve block. They include anatomical variations between patients, operator technique and needle deflection.
[0007] Contemporary dental anesthesia textbooks attribute needle deflection as a source of anesthesia failures. It has been reported that the IA rate of failure can range from 20% to 30% and most dentists have experienced some difficulty with this injection. The inferior alveolar nerve is contained within the pterygoman-dibular space. For a needle tip to be in close proximity to the intended target, it must penetrate a variety of tissue types including mucosa, buccinator muscle, submucosal connective tissue, fat and the temporopterygoid fascia.
[0008] The needle initiates its path when it first enters through the buccal mucosa at a point between the pterygomandibular raphe and temporal crest of the mandible ramus. The mucosa should be held firmly in place during insertion for precise needle entry. The standard technique requires needle penetration of the buccinator muscle and fascia. As the needle advances it will traverse the connective tissue and adipose tissue found within the pterygomandibular space. The final intended target for the needle is the mandibular foramen found distal and inferior to the mandible lingula . All these tissue layers offer varying degrees of resistance to needle penetration. The entire inferior alveolar neurovascular bundle has a diameter of approximately 2.2 mm, and the pterygomandibular space has a total estimated volume of only 2 cc. Deviation from the final intended target, no matter how small, may have a negative effect on the success of an IA nerve block.
[0009] It has long been suggested that all needles deflect irrespective of the diameter of the needle being used. Aldous (identified above) was the first to devise a dynamic testing method to record deflection and he concluded that needle deflection was inversely related to needle diameter.
[0010] Robinson(identified above) investigated deflection modifying Aldous's model to improve the measuring and recording accuracy. Robinson concluded that all the needles tested deflected irrespective of gauge. Robinson stated that the degree to which needles deflect is not related to diameter shaft, but maybe more related to the specific metals used in manufacturing.
[0011] A previous study has shown that bevel tip design of a needle will influence the path the needle takes as it penetrates through substances of varying densities. It is apparent that a force system is produced on the needle bevel surface. This force vector system is the same for any cylindrical object with a beveled end and it will follow Newton's third physical law of equal and opposite forces. Therefore, an application of a resultant vector force on the beveled surface of an eccentric pointed cylindrical shaft will produce physical bending (deflection) along the path of insertion as illustrated in more detail below. The amount of deflection exhibited by the beveled cylindrical object is determined by the sum of the forces acting on an object in a specific medium.
[0012] A bi-beveled needle has the advantage of possessing a needle tip that is centrally located along the needle shaft. Testing this needle design yielded the expected results of reduced needle shaft deflection. The bi-beveled needle eliminates the perpendicular forces that are responsible for needle shaft deflection. However, the most common needle commercially available is an eccentrically pointed beveled needle. Another novel needle is the Accujet® needle (Astra Pharm., Wayne, Pa). This needle enables bevel orientation to be monitored. A visual marker on the needle hub allows the operator to position the bevel in a specific direction. It is thought that this will assist the dentist in better control to the final needle position. The needles listed above require the operator to use a linear insertion technique.
[0013] Berns and Sadove conducted a radiograhic in-vivo study. Sixty-six IA nerve block injections were performed on adult patients using a 22-gauge needle administering a mixture of local anesthestic and radiopaque dye. Cephalometric lateral head films were taken with the needle inserted to the proper depth, and securely positioned in place. Review of the reproduced radiographic images appearing in the article demonstrates needle bending with a rigid 22-gauge needle at its final position. The authors stated that the needle tip should be no more than 0.5 cm from the mandibular foramen. They concluded the closer the needle tip placement to the mandibular foramen, the more likely the success of the IA nerve block. The study's conclusion supports the observation that there is a direct correlation between a positive clinical outcome, i.e. anesthesia and the positioning of the needle tip. The study documents radiographic evidence of in-vivo needle deflection. It is therefore not unreasonable to infer that needle deflection affects final needle tip position thus affecting clinical success.
[0014] Needle deflection (i.e. bending) is also know to be a contributing factor to inaccurate needle placement and reduced success of injection techniques (Jasktak JT, Yagiela JA, Donaldson D. Local Anesthesia of the Oral Cavity. Philiadephia: WB Saunders Co; 1995. Malamed S. Handbook of Local Anesthsia. 4 th Ed. St. Louis: Mosby; 1997.) Currently there are no known techniques available that enable the user to provide an injection with an eccentric pointed hollow core needle in a manner with reduces or eliminates needle deflection and its undesirable side effects.
[0015] Existing needle device are known which incorporate rotating mechanism however these were designed specifically for drilling through bony tissues and do not use rely on, nor do they provide a high tactile control during use.
[0016] To summarize, all of the above-described prior art have either one or more of the following deficiencies. They describe needle insertion techniques that are cumbersome and do not provide for or even recognize the advantages of using a bidirectional rotational technique for administering injections. Existing devices are cumbersome to perform. Exiting syringes and the like are not designed to allow the operator to use a bi-rotational insertion technique for entry and removal. Exiting syringes and the like are not designed to allow the operator to use a rotational insertion technique for entry and removal
OBJECTIVES AND SUMMARY OF THE INVENTION
[0017] The proposed invention has been designed to reduce or eliminate the undesirable effect of needle deflection. In addition the proposed invention has been designed to reduce the force required during needle penetration and insertion of an eccentric pointed hollow core hypodermic needle.
[0018] An objective of the present invention is to provide a technique or method which can be used to provide injections in a manner selected to reduce or eliminate the undesirable effect of needle deflection.
[0019] A further objective is to provide a method adapted to reduce the force required during needle penetration and insertion of an eccentric pointed hollow core hypodermic needle.
[0020] The subject invention pertains to a novel needle insertion technique designed to overcome the undesirable effect of needle deflection. This technique seeks to produce a more accurate, linear needle tracking through substances regardless of needle gauge. In one embodiment of the invention, the technique relies on a pen-like grasp that makes it possible to rotate a needle in a back-and-forth manner. The needle is rotated between the thumb and index finger 180 degrees in each direction. The type of rotation used is analogous to techniques that have been described for endodontic file instrumentation and acupuncture, however, those techniques no fluid is injected from a needle. More importantly in these latter techniques a needle is first inserted linearly into a tissue and then rotated.
[0021] The purpose of the bi-directional rotation is to neutralize the force vectors that act on the needle bevel that make the needle shaft bend. This bi-directional rotation action is preferably maintained during the entire course of needle advancement In order to validate the technique, a study has been performed to test the bending of needles under various conditions. During this testing a protocol for the study followed the design set forth by Robinson (identified above).
[0022] Three deflection test models were constructed. The test models differed in the tissue-like substances that were used. In each of the three models, the needle was inserted to a depth of 20 mm. This standardized working length was selected on the availability of a 30-gauge 1 inch (25.4 mm) needle.
[0023] These tests have shown that use of the bi-directional rotation insertion technique, even with an eccentric-point bevel needle, allows the operator to cancel-out the perpendicular force vectors on the bevel that cause bending along the needle shaft. The technique generates resultant forces that promote the needle to travel in a linear path. The straight path produced by the bi-directional rotational insertion technique occurs irrespective of needle gauge, bevel design or the metal alloys used in manufacturing.
[0024] The present inventor has further discovered that needle deflection requires increased penetration force during the administration of an injection. It is believed that this increased penetration force results in increased and unnecessary tissue damage as well.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] [0025]Fig. 1A shows how a standard injection syringe is held;
[0026] [0026]FIG. 1B shows how a Wand-type injection handle is held;
[0027] [0027]FIG. 2A shows the force vector system on a needle during a standard linear insertion technique;
[0028] [0028]FIG. 2B shows the force vector system on a needle during the inventive bi-directional insertion system;
[0029] [0029]FIG. 3A and 3B each show typical deflections for needles inserted using a standard linear technique as opposed to a bi-directional technique, the two graphs being taken orthogonally with respect to each other;
[0030] [0030]FIG. 4 shows a chart for the range, average and standard deviation of the deflections for a 30, 27 and 25 gauge needle ,using the standard and the bidirectional insertion techniques.
DETAILED DESCRIPTION OF THE INVENTION
[0031] [0031]FIGS. 1A and 1B show two different means by which an injection may be performed using a standard linear insertion technique. FIG. 1A shows a standard palm/thumb grasp used on a syringe with a needle (usually having a beveled tip-not shown in the Figure). FIG. 1B shows a pen grasp for holding a handle terminating with a needle. The handle may be part of an automatic injection pump such as the WANDS ® available from Milestone Scientific Corporation of Livingstone, New Jersey.
[0032] The present inventor has discovered that all the problems associated with injections discussed above can be eliminated with a novel bidirectional injection technique. The proposed technique and its advantages are best understood by reviewing the somewhat diagrammatic illustrations of FIGS. 2A and 2B. In FIG. 2A a needle N having a lumen L is advanced linearly (using the grasp of FIG. 1A or 1 B, for example) in the direction indicated by arrow D while a fluid F is being injected through the lumen L. The advancement of the needle is resisted by the force R generated by the tissues (not shown) and because of the beveling of the needle, a transversal force T is generated which causes the needle N to bend or deflect as indicated by the arrow DF. However, if the needle is rotated first in one direction A 1 and then in a second direction A 2 , the effects of transversal forces T 1 , T 2 cancel and are neutralized, or, at least, minimized causing the needle to be inserted in a relatively straight manner, as indicated by arrow S.
[0033] The amount of rotation to be imparted to the needle depends at least to some extent on the amount of its longitudinal travel, which in turn depends on the depth within the tissue at which a drug needs to be and the speed at which the needle is advanced. Typically, the needle is advanced at about 2-4 mm/sec. For a shallow depth of about 2-4 mm, the total rotation imparted to the needle may be relatively small. For example, the needle may be rotated by 180 degrees in one direction and 180 degrees in the other. For longer travel distances, the needle may be rotated in several cycles, each cycle comprising rotating the needle by an angle A and then rotating the needle in the opposite direction by the same angle A. As discussed above, preferably A is 180 degrees although it may be other values as well. Moreover, the needle need not be rotated by the same angle A each time, and need not be returned to the same angular position. Similar effects may be obtained if, instead of rotating the needle back and forth in two directions, it is continuously rotated in a single direction over, for example, 360 degrees.
[0034] The traditional handheld syringe requires a palm-thumb grasp (FIG. 1A) and does not lend itself easily to the rotational insertion technique. This may explain why the technique has not been described in the past. However the recently introduced anesthetic delivery system (The WandTM, Milestone Scientific, Inc., Livingstone, Nj) illustrated in FIG. 1B was designed to use a lightweight, disposable pen-like handpiece requiring the operator to use a thumb and index finger grasp. The benefits of a bidirectional rotation insertion technique can be maximized with this pen-like grasp.
[0035] Thus the bidirectional rotational movement of the needle may be accomplished either manually or automatically. If a handle is used to administer an injection, as shown in FIG. 1B then the needle can be rotated back and forth easily by 180 degrees (or any other angle) by merely rotating the handle as the needle is advanced. Alternatively, the needle may be rotated automatically as it advances, as it is disclosed in commonly assigned co-pending application Ser. No. 506,484 filed Feb. 17, 2000 entitled A HAND-PIECE FOR INJECTION DEVICE WITH A RETRACTABLE AND ROTATING NEEDLE and incorporated herein by reference. This application discloses a needle which is normally disposed in a housing to protect health practitioners from being pricked. The needle can be selectively advanced in a longitudinal direction so that it can extend outwardly of the housing. In one embodiment, the needle rest on a support which includes an extension engaging a helical track inside the housing. As the needle is advanced and retracted, the extension rides in the helical track in a caming action causing the needle to rotate in a first direction and then in a second direction.
[0036] In order to validate this concept, a rigorous set of in vitro tests have been conducted to study needle penetration and deflections. The most widely accepted model for studying needle deflection is an in-vitro model utilizing tissue-like substances. This type of experimentation provides a reliable testing environment without the need for human tissues and eliminates many of the difficult ethical questions raised by animal studies. It is known that this type of testing provides valuable insight into needle characteristics in an experimental setting.
[0037] Early studies have shown that needle diameter (gauge) and the relative flexibility or resilience of the needle shaft are some of the physical characteristics reported to affect needle deflection. These early studies have also concluded that shaft diameter is the most critical factor affecting bending or deflection of the needle.
[0038] Controversy in the literature exists regarding the factors responsible for needle deflection. The inventor has conducted a study to determine if using a new bi-directional rotation insertion technique could minimize needle deflection.
[0039] Testing Methods and Materials
[0040] Three deflection test models were constructed. The test models differed in the substances used to simulate tissues. In each of the three models, the needle was inserted to a depth of 20 mm. This standardized working length was selected on the availability of a 30-gauge 1 inch (25.4 mm) needle. The following materials served to simulate tissues: hydrocolloid (test material A), frankfurters (test material B), and soft bite wafer wax (test material C). These test materials have various densities to simulate various types of tissues.
[0041] All three tests employed a modified dental surveyor (Ney Co., Chicago, Il.) to produce standardized needle insertions. For each material three different size needle gauges were tested: a 30-gauge 1 inch needle; a 27-gauge and a 25-gauge needle, the last two needles being 1 ¼ inch long (MonojetUltra ® Sharp Model 400, Sherwood Medical Co., St. Louis, Mo). Traditional Luer type connectors were attached to a customized arm of the surveyor. The needle was then advanced into each material using either the transitional linear or the bidirectional rotation insertion technique. A sufficient number of tests were performed for each needle within a substance to provide for adequate statistical relevance.
[0042] Tests Using Material A
[0043] A hydrocolloid material (Acculoidl™ Extra Strength, Van R Dental Products, Inc. Product #11110) was placed into a 6-oz. plastic container which fit into the custom surveyor jig. The jig was constructed to produce consistent, perpendicular orientation of the x-ray tube head. The custom jig was designed to record needle deflection in orthogonal two planes. This enabled the total amount of deflection to be determinable from a simple algebraic formula. A total of 60 insertions were performed using 30 needles (10 needles for each needle gauge size).
[0044] Each needle served as its own control between the two techniques. The needle was first inserted into the tissue-like substance with a linear non-rotating movement. The same needle was then inserted into the test material using the bi-directional rotation insertion technique. After the needle was used for the second insertion technique it was discarded and the test was repeated using a new needle.
[0045] After each needle insertion two x-ray films were exposed at 15MA, 65 KVP, 10 impulses and then developed. A metallic x-ray grid was used to record the maximum amount of deflection produced. Each film was measured with a Boley gauge on a superimposed grid from the point of insertion to the tip of the needle. The total amount of deflection produced was calculated using a geometric principle as described by Robinson.
[0046] Tests On Material B
[0047] Deflection test material-B was a processed precooked meat-namely, frankfurters (Hebrew National, Inc., Bronx, Ny). The identical protocol of the test for material A was followed. A total of 42 insertions were performed using
[0048] Rotatinal Insertion Technique 21 needles (7 needles for each needle gauge size, 30, 27 and 25-gauge).
[0049] Tests On Material C
[0050] Material C was made of a soft wax bite-wafer (The Hygenic Corp. Akron, Oh). A custom platform was constructed which aligns the wax parallel to the long axis of the needle held by the dental surveyor arm. The use of soft wax bite-wafer allowed visual inspection to measure and determine the amount of needle deflection observed.
[0051] Orientation of the needle bevel was perpendicular to the surface of the wax, and this was confirmed by the operator wearing 2.5x magnification loops (Designs for Vision, Inc. Ronkonkoma, Ny). The needle was first inserted to a depth of 20 mm into the wax using a non-rotational linear movement. Marking the wax at a point were the needle tip ended in the wax identified the deflection. The needle was removed from the wax and positioned in front with the needle shaft aligned to the access hole created from the initial insertion. A Boley gauge was used to measure the distance of deflection that was observed. The same needle was employed for the second test, the bi-directional rotation insertion technique. Each needle therefore served as its own control. A total of 100 insertions were performed using 50 needles of a 30-gauge size. An additional 40 insertions using 10 needles each of 27 and 25-gauge was conducted to compare the two techniques. The needles used for this study were randomly selected from a standard box of 1100 needles as supplied by a local dental distributor.
[0052] Results
[0053] [0053]FIGS. 3A and 3B show typical results of these tests. More specifically, in FIG. 3A, needle N 1 was inserted using a standard linear technique and needle N 2 was inserted using the subject bidirectional rotational technique. The large amount of deflection caused by the standard linear technique when compared to the deflection of needle N 2 is clearly visible in this Figure. In FIG. 3B taken orthogonally to FIG. 3A, virtually no deflection for either needles N 1 , N 2 is seen because of the way the two sets of radiographs have been selected so that maximum deflection (as determined by the beveling of the needles) is visible in FIG. 3A.
[0054] Statistical data analysis was performed by paired T-tests for each experiment. The rotational technique described was consistently more effective in minimizing and eliminating needle shaft deflection for a 30-gauge, 27-gauge and 25-gauge needle. Each of the different tissue-like substances tested consistently demonstrated this reduction in needle deflection with the bi-directional rotation insertion technique.
[0055] Differences in deflection between linear and rotational insertion were found to be statistically Insignificant (P<.05) in each of the experiments conducted. A 95% confidence level with no overlap of the upper and lower limits was observed.
[0056] When comparing linear insertion to bidirectional rotation insertion, the mean amount of total deflection of a 30-gauge needle in wax was 2.7 mm vs. 0.1 mm, respectively. In hydrocolloid, the total mean deflection was 4.7 mm vs. 1.1 mm comparing linear to rotational insertion. In frankfurters, the total mean deflection between linear and rotational insertion was 2.2 mm vs. 0.2 mm.
[0057] The comparison of linear to bi-directional rotation insertion technique for a 27-gauge needle was as follows: total mean deflection in wax was 3.4 mm vs. 0.1 mm, in hydrocolloid was 4.6 mm vs. 0.8 mm, in frankfurter was 1.4 mm vs. 0.6 mm respectively.
[0058] The comparison of linear to bi-directional rotation insertion technique for a 25-gauge needle was as follows: total mean deflection in wax was 2.6 mm vs. 0.1 mm; in hydrocolloid 3.8 mm vs. 0.5 mm; in frankfurter 0.9 mm vs. 0.2 mm respectively.
[0059] In addition, the bi-directional rotational insertion technique also reduces substantially the force required to push the needle to penetrate tissues. Preliminary data suggests that a reduction of force penetration in the range of 40% to 50% can be anticipated when using of this technique. This may prove to be particularly beneficial for those injections that penetrate dense connective tissue, i.e., palatal tissue of the oral cavity.
[0060] The density of the substance that a needle is inserted into appears to influence the amount of deflection produced by the bevel. Tissue-like substances with greater density, i.e., hydrocolloid, consistently produced greater deflection compared with less dense substances. Encountering a fluid filled compartment would minimize deflection relative to the fluid viscosity. The oral cavity is primarily composed of tissues with a spectrum of varied densities. These densities fall within a broad range.
[0061] In the testing model, it was critical to provide a consistent and uniform material to eliminate variations between samples. A variety of different types of materials were tested reflecting a range of different densities. There are no published studies available that quantify densities of oral tissues in the infratemporal fossa. The materials selected offered a reasonable spectrum that is analogous to tissues that might be encountered. It is apparent that the type of insertion technique used had the greatest influence on the amount of deflection produced irrespective of the density of the substance tested.
[0062] Needle length appears to be another factor that influences the amount of deflection. The standard testing distance of 20 mm was selected in this study based on the commercial availability of a 30-gauge, 1 inch needle. It is noted that insertion distances of 25 mm and more are typical for the IA nerve block. It would be expected that these greater distances would reflect greater rates of deflection. Longer needles that travel greater distances will demonstrate larger amounts of bending then those observed in this study. This would only accentuate this study's finding.
[0063] The increased length of the thicker needle can explain the finding of increased needle deflection of 27-gauge needles compared to 30-gauge needles in the denser tissue-like substance (wax). The standard 27-gauge needle is ¼ inch (6mm) longer than the 30-gauge needle producing increased “springiness”. This could account for the greater bending of the needle that is observed. Irrespective of differences between the different needle sizes, all needles demonstrated a significant reduction in deflection with the bi-directional rotation insertion technique.
[0064] The study design always tested linear insertion followed by rotational insertion. Maintaining this order of needle insertions was believed to minimize bias produced from a dulling or deforming of the needle.
[0065] This study has demonstrated that a needle that traverses 20 mm of a tissue-like substance can deflect as much as 5 mm. The bi-direction rotation insertion technique provides greater accuracy of placement for those injections that require deep needle penetration.
[0066] For injections in the palate or other supraperiosteal infiltration injections, high-level accuracy may not be necessary to achieve successful anesthesia. However, it was noted that all needle penetrations required reduced force when the bi-directional rotation technique is used. This suggests that the needle penetration force may be reduced by the rotational insertion technique.
[0067] Conclusion
[0068] The success of local anesthesia in dentistry is multi-factorial. One of the most challenging of all local anesthesia injections is the inferior alveolar nerve block. Not all anesthetic failures are related to needle deflection. However, needle deflection has been identified as one of the elements that can reduce the accuracy and predictably of the IA nerve block. This study was conducted to investigate the cause and effect relationship between the needle and deflection.
[0069] The factor that most greatly affects the path taken through a tissue-like substance by an eccentric beveled needle is the force vectors that act upon the beveled surface.
[0070] The use of a bi-directional rotation insertion technique minimizes needle deflection, resulting in a straighter tracking path for the 30-, 27- and 25-gauge dental needles.
[0071] The use of a bidirectional rotation insertion technique minimizes needle deflection in the three different tissue-like substances tested in this study.
[0072] Modifications may be to the invention described herein without departing from its scope as defined in the appended claims.
|
A drug is administered to a patient through a beveled needle by rotating the needle as it is advanced into tissues. The rotation of the needle insures that the needle is not deflected as it is advanced. In this manner, the amount of pain felt by the patient may be reduced, and the drug is delivered to accurately to the selected site.
| 0
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] Aerosol actuators for mating to an aerosol can and more particularly, aerosol actuators with a valve having anti-drool features.
[0003] 2. State of the Art
[0004] Aerosol actuators, and more recently trigger actuated aerosol actuators, may include a manifold which fits to or communicates with a valve on an aerosol container or can. Aerosol containers or cans typically contain a propellant such as a compressed gas or a volatile hydrocarbon. The contents of the container, along with the propellant, are held in the container by a container valve. The actuator opens an outlet flow channel between the container valve and an outlet device such as a spray nozzle. After dispensing contents from such containers, portions of the dispensed materials are loosely retained in the actuator downstream of the container valve, but upstream of the spray nozzle. These loosely retained contents may seep or ‘drool’ out of the nozzle, especially if the contents tend to expand, which may be particularly true for hydrocarbon propellants. Thus, an improved actuator that prevents drool is desired.
BRIEF SUMMARY OF THE INVENTION
[0005] In one embodiment of the invention, an actuator is disclosed. The actuator includes a manifold; a discharge valve positioned in the manifold and slidably movable between a first position and a second position; and a seal positioned on the discharge valve, wherein the seal closes an outlet in the first position and opens the outlet in the second position. The actuator also includes a first spring element to bias the discharge valve toward the first position; a trigger having an actuated and a non-actuated position; a trigger ramp movable between a first ramp position that permits the discharge valve to slide toward the first position, and a second ramp position that permits the discharge valve to slide toward the second position. The trigger ramp moves to the second ramp position when the trigger is moved to the actuated position.
[0006] In another embodiment of the invention, an actuator is disclosed that includes a a manifold having a manifold axis; a valve slidably positioned in the manifold for movement along the manifold axis between a first position and a second position; a seal positioned on a first end of the valve that closes an outlet from the manifold when the valve is slid toward the first position; a first spring force to bias the valve toward the first position; a trigger having an actuated and a non-actuated position; a trigger ramp movable between a first ramp position that permits the valve to be slid toward the first position and a second ramp position that permits the valve to be slid toward the second position. The trigger ramp moves to the second ramp position when the trigger is moved to the actuated position, and the trigger moves about a trigger pivot point located between the trigger and the manifold axis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] While the specification concludes with claims particularly pointing out and distinctly claiming particular embodiments of the present invention, various embodiments of the invention can be more readily understood and appreciated by one of ordinary skill in the art from the following descriptions of various embodiments of the invention when read in conjunction with the accompanying drawings in which:
[0008] FIG. 1 illustrates an exploded perspective view of parts of an aerosol actuator according to certain embodiments of the invention;
[0009] FIG. 2 illustrates an exploded detail view of certain parts of a flow path through an aerosol actuator according to various embodiments of the invention;
[0010] FIG. 3 illustrates a side cross section view of a grip body housing and actuator spring;
[0011] FIG. 4A illustrates a side view of a trigger and a grip body housing;
[0012] FIG. 4B illustrates a top front perspective view of an assembled grip body housing and trigger;
[0013] FIG. 5A illustrates a top back perspective view of a grip body housing assembled with a manifold;
[0014] FIG. 5B illustrates a side cross section view of the grip body housing assembled with a manifold illustrated in FIG. 5A ;
[0015] FIG. 6A illustrates a front cutaway view of a grip body housing with a cover attached;
[0016] FIG. 6B illustrates a side cross section view of an actuator according to various embodiments of the invention;
[0017] FIG. 7A illustrates a side cross section view of an actuator in a locked state;
[0018] FIG. 7B illustrates a partial side cutaway view of an actuator in a locked state;
[0019] FIG. 8A illustrates a side cross section view of an actuator in an unlocked state;
[0020] FIG. 8B illustrates a partial side cutaway view of an actuator in an unlocked state;
[0021] FIG. 9A illustrates a side cross section view of an actuator in an actuated state;
[0022] FIG. 9B illustrates a partial side cutaway view of an actuator in an actuated state;
[0023] FIG. 10A illustrates a cross section detail of a portion of FIG. 7B showing the interaction of a trigger ramp, forward pushing point, and cross posts in a locked state;
[0024] FIG. 10B illustrates a cross section detail of a portion of FIG. 8B showing the trigger ramp, forward pushing point, and cross posts in an unlocked state;
[0025] FIG. 10C illustrates a cross section detail of a portion of FIG. 9B showing the trigger ramp, forward pushing point, and cross posts in an actuated state;
[0026] FIG. 11 illustrates an exploded perspective view of parts of an aerosol actuator according to certain embodiments of the invention;
[0027] FIG. 12 illustrates a side cross section of an aerosol actuator according to certain embodiments of the invention;
[0028] FIG. 13 illustrates an aerosol actuator according to various embodiments of the invention with a single-piece control valve; and
[0029] FIG. 14 illustrates an aerosol actuator according to various embodiments of the invention with a ball check valve.
DETAILED DESCRIPTION OF THE INVENTION
[0030] According to various embodiments of the invention, an aerosol actuator may include certain parts shown in FIG. 1 which illustrates an exploded perspective view. The parts of the aerosol actuator 100 may include a cover 110 , a discharge valve actuator 120 , a discharge valve 130 , a manifold 140 , an orifice cup 150 , a stem actuator 160 , a trigger 170 , a spring 180 , and a grip body housing 190 . According to various embodiments of the invention, an actuator 100 , or parts thereof, may be made of any selected material. In some embodiments, the parts may be made of plastics such as polypropylene, polyethylene, acetal, and other plastics. For example, in certain embodiments, an aerosol actuator 100 may include a polypropylene (PP) cover 110 , a polyethylene (PE) discharge valve actuator 120 , a PE discharge valve 130 , a PP manifold 140 , an acetal orifice cup 150 , a PE stem actuator 160 , a PP trigger 170 , an acetal spring 180 , and a PP grip body housing 190 .
[0031] In the description of the Figures, directional terms such as forward, backward, upper, lower, etc. may be used to indicate relative positions of certain parts. These presence or absence of such terms is not meant to be limiting, but rather to help explain the structure and operation of the aerosol actuator 100 . It should be understood that such direction terms are used relative to the orientation of the aerosol actuator as shown in the Figures.
[0032] FIG. 2 illustrates an exploded detail view of parts which may comprise a flow path through an aerosol actuator 100 according to certain embodiments of the invention. These parts may generally be housed within, assembled with, or connected to, a manifold 140 . A manifold may include a manifold inlet 141 . A manifold may also include a manifold outlet 143 .
[0033] A lower part of the flow path may include stem actuator 160 that is received into manifold inlet 141 . Stem actuator 160 may have one or more stem posts 162 . Stem actuator 160 may have a second or lower end 163 that may fit on a male aerosol container valve 196 (see FIG. 7A ). Stem actuator 160 may have a first or upper end opposed the second end. A stem actuator 160 may also have, at the first or upper end, one or more stem chevron seals 164 that fit into manifold inlet 141 . A stem chevron seal 164 may seal the first or upper end of the stem actuator 160 to or with the manifold inlet 141 .
[0034] It should be understood that the parts of aerosol actuator 100 may be single-piece or unitary parts, or the parts may be made of multiple subparts. For example, in some embodiments of the invention, a stem actuator 160 may be a single piece, or may be made of several separate pieces that are assembled or joined together in any suitable manner. The same is true of the other parts used in the aerosol actuator. For example, in other embodiments of the invention, a manifold 140 and stem actuator 160 may be molded as a single part such that a stem chevron seal 164 is not needed on the stem actuator 160 because the stem actuator 160 portion would be an extension of the manifold 140 . In some embodiments, a combination manifold 140 and stem actuator 160 could include a bi-injected part such that the manifold 140 and stem actuator 160 are different materials.
[0035] A manifold outlet 143 may be provided at the first or front end of manifold 140 . A manifold outlet 143 may receive an orifice cup 150 . A manifold 140 may house a discharge valve 130 which at its first or front end may have a conical seal 132 and a post 133 . Discharge valve 130 may move slidably between a first or forward position and a second or rearward position in manifold 140 . A discharge valve 130 at its second or back end may have one or more interlocking features 131 that may fit into or onto discharge valve actuator 120 . A first or front end of discharge valve actuator 120 may contact the second or back end of the discharge valve 130 . A discharge valve actuator may have a manifold chevron seal 123 fitting into an opening 142 on the second or back end of the manifold 140 . This manifold chevron seal 123 may prevent leakage from the second or back end of manifold 140 . A discharge valve actuator 120 may have cross posts 121 . A discharge valve may have a back surface 122 that bears on a spring 180 as described below. Manifold 140 may have one or more manifold mounting holes 144 to secure the manifold 140 to the grip body housing 190 .
[0036] FIG. 3 illustrates a side cross section view of grip body housing 190 with spring 180 inserted therein according to certain embodiments of the invention. A spring 180 may be made of a relatively stiff and somewhat resilient material such as acetal. In some embodiments, the spring 180 may have a generally L-shaped aspect. The lower corner of the spring 180 may be considered a relatively fixed point, although a limited rocking motion may occur here. The spring may include one or more trunnions 181 . The trunnions 181 may be located at or near a corner of the L-shape along with one or more spring tangs 182 . The spring tangs 182 may snap or lock the spring 180 into the grip body housing 190 . The vertical leg of spring 180 may terminate at forward-pushing point 183 . The lower portion of the spring may rest upon or against back wall 191 . The spring 180 horizontal leg may terminate at upward-pushing point 184 .
[0037] Although spring 180 is shown as L-shaped, a spring may have other shapes. A spring 180 according to embodiments of the invention may also have more than one part, for example a spring 180 may include a first spring element to provide the forward-pushing point 183 , and a second spring element to provide the upward-pushing point 184 .
[0038] As illustrated in FIG. 3 , a grip body housing 190 according to certain embodiments of the invention may also include one or more trigger pivot supports 192 and one or more manifold support posts 193 .
[0039] FIG. 4A illustrates a side view of a possible assembly step of placing trigger 170 into grip body housing 190 . The forward-pushing point 183 of the spring 180 is shown within the grip body housing, as is a manifold support post 193 , one or more of which may extend from the grip body housing 190 . Trigger 170 may be assembled with grip body housing 190 by lowering the trigger forward as denoted by arrow A 1 , and then rocking it backward as denoted by arrow A 2 , so that the trigger pivot trunnion 171 may be received by trigger pivot support 192 (shown in FIG. 3 ). Also shown on trigger 170 is trigger ramp 173 .
[0040] FIG. 4B illustrates a top front perspective view of the grip body housing 190 with trigger 170 installed.
[0041] FIG. 5A illustrates a top back perspective view of the grip body housing 190 with the manifold 140 assembled with the grip body housing 190 . One or more manifold mounting holes 144 may be exist on manifold 140 and may receive manifold support posts 193 . Extending from the second or back end of the manifold 140 may be discharge valve actuator 120 . Forward-pushing point 183 may push against the second or back end of discharge valve actuator 120 . Trigger ramp 173 may straddle the discharge valve actuator 120 just forward of cross posts 121 and just behind the second or back end of manifold 140 . FIG. 5B illustrates a side cross section view of the same parts.
[0042] FIG. 6A illustrates a front cutaway view of the grip body housing 190 with cover 110 attached, and showing the manifold 140 within. FIG. 6B illustrates a side cross section view of the same.
[0043] FIGS. 7A through 9B illustrate an actuator 100 in locked, unlocked, and actuated states according to various embodiments of the invention.
[0044] FIG. 7A illustrates a side cross section view of the actuator in a locked state. FIG. 7B illustrates a partial side cutaway view. Forward-pushing point 183 of the spring 180 may bear forward on the back of discharge valve actuator 120 . Conical seal 132 may seal the front of the manifold 140 and may prevent drooling from the actuator. Manifold chevron seal 123 may seal the back of the manifold 140 . Stem chevron seal 164 may seal the first or upper end of the stem actuator 160 into the manifold inlet 141 . The second or lower end 163 of stem actuator 160 may receive the upper end of male aerosol container valve 196 . It will be noted that in the locked state, trigger 170 may rest fairly high up in the actuator. In particular, trigger engagement point 172 may be clear of the spring upward-pushing point 184 , and the trigger ramp 173 may be located relatively high with respect to the discharge valve actuator 120 . A detail of highlight areas 10 A is explained later with reference to FIG. 10A .
[0045] FIG. 8A illustrates a side cross section view of the actuator in an unlocked state with the trigger 170 pivoted slightly downward. The unlocked state may also be considered a non-actuated position. FIG. 8B illustrates a partial side cutaway view. Forward-pushing point 183 of the spring 180 may bear forward on the back of discharge valve actuator 120 . Conical seal 132 may seal the front of the manifold to prevent drooling from the actuator. Due to force exerted by the lowered trigger 170 onto stem posts 162 , the second or lower end 163 of stem actuator 160 may move toward aerosol container valve 196 (e.g., downward as viewed in the Figure) toward the upper end of male aerosol container valve 196 , so that the aerosol container valve 196 may be opened if the trigger is pulled farther. It will be noted that in the unlocked state or non-actuated position, trigger 170 may rest a little lower in the actuator. In particular trigger engagement point 172 may be close to or may touch the upward-pushing point 184 of spring 180 .
[0046] FIG. 9A illustrates a side cross section view of the actuator in an actuated state with the trigger 170 pivoted farther downward. FIG. 9B illustrates a partial side cutaway view. Forward-pushing point 183 of the spring 180 may still bear forward on the back of discharge valve actuator 120 . The downward movement of the trigger ramp 173 may act as a lever or wedge and may force back the discharge valve actuator 120 . Forces upon the valve actuator 120 , such as forces provided by the trigger ramp 173 or forward-pushing point 183 , may in turn be transmitted via the discharge valve actuator 120 and to discharge valve 130 . Thus, the trigger ramp 173 may pull upon or allow the discharge valve 130 to move toward the second or rear position, causing conical seal 132 to move back and unseal from the front of manifold 140 to allow liquid to flow through the manifold. Due to further force exerted by lowered trigger 170 onto stem posts 162 , the second or lower end 163 of stem actuator 160 may move sufficiently farther (e.g. downward as viewed in FIG. 9B ) onto the upper end of male aerosol container valve 196 to open that valve. It will be noted that in the actuated state, trigger engagement point 172 having moved downward may have flexed the lower arm of spring 180 , which resists by providing force on the spring upward-pushing point 184 , resisting the trigger and attempting to force it back to the unlocked position.
[0047] FIG. 10A illustrates a detail showing the trigger ramp 173 in a locked state where it may occupy a first or closed ramp position. The trigger ramp 173 may act as a sort of wedge, located in the space between cross posts 121 of the discharge valve actuator 120 , and the back of the manifold 140 . The trigger ramp 173 may be tilted slightly forward relative to ramp flexing point 173 A where it connects to the trigger proper. The forward-pushing point 183 may bear against back surface 122 of the discharge valve actuator 120 , which may maintain the discharge valve actuator 120 and the discharge valve 130 in a closed (forward) state.
[0048] FIG. 10B illustrates a detail showing the trigger ramp 173 in an unlocked state where it may still occupy a first or closed ramp position. As the trigger 170 moves yet further, the trigger ramp 173 may move downward with the trigger 170 , so that the trigger ramp 173 may now generally fill the space between cross posts 121 of the discharge valve actuator 120 , and the back of the manifold 140 so that any farther movement will start to open the discharge valve 130 . The trigger ramp 173 may be aligned generally vertically relative to ramp flexing point 173 A where it connects to the trigger 170 proper.
[0049] FIG. 10C illustrates a detail showing the trigger ramp 173 in a second or actuated state or position. As the trigger itself rotates downwards, its upper parts may move forward, including ramp flexing point 173 A. The ramp may be pulled downward and forward, and may encounter fulcrum point 173 B that may be located on the back of the manifold, or on another structure such as the grip body housing 190 . As the lower part of the trigger ramp 173 moves forward, the upper half may tilt backward, which may force back the cross posts 121 of the discharge valve actuator 120 . The forward-pushing point 183 may provide resistance against this backward movement, but discharge valve actuator 120 and the attached discharge valve 130 may nonetheless move backward, opening the conical seal 132 and allowing fluid to flow from the manifold 140 , through orifice cup 150 , and out the nozzle.
[0050] Note that trigger pivot trunnion 171 may be located below the axis of manifold 140 as illustrated in FIG. 9A . When trigger 170 is actuated or pulled back, it may rotate “clockwise” or generally downward and backward. Any structure rigidly attached to the trigger and extending up to the axis of manifold 140 would be expected to move forward relative to the manifold. The use of the trigger ramp 173 with fulcrum point 173 B causes the same trigger motion instead to provide a backward motion relative to manifold 140 , which may be used to advantageous effect here to open the discharge valve 130 by pulling back on the discharge valve actuator 120 .
[0051] Once trigger 170 is released, spring upward-pushing point 184 bearing on trigger engagement point 172 may return trigger 170 to the unlocked position. Consequently trigger ramp 173 may rise upward, removing the backward force against cross posts 121 and allowing forward-pushing point 183 to push forward on back surface 122 of discharge valve actuator 120 , in turn pushing forward on discharge valve 130 and closing the conical seal 132 to prevent drool. At the same time the trigger rising upward may remove the downward force on stem posts 162 , allowing the stem actuator 160 to move upward as urged by the upward force from aerosol container valve 196 .
[0052] FIG. 11 illustrates an exploded perspective view of parts of an aerosol actuator according to another embodiment of the invention. This embodiment is similar to that shown in FIG. 1 , except that the stem actuator 161 may be adapted to fit a female aerosol valve 197 . In particular as can be seen in the side cross section of FIG. 11 , the stem actuator 161 may be cylindrical at its bottom and may fit directly into female aerosol valve 197 .
[0053] FIG. 13 illustrates an embodiment with a single-piece control valve made up essentially of a valve portion 130 A and a valve actuator portion 120 A. The forward seal 132 A may be a form different from or the same as conical seal 132 seen in the previous Figures.
[0054] FIG. 14 illustrates an embodiment with a ball check valve 165 that may be located in the flow path, for example at the first or upper end of stem actuator 161 (or 160 ).
[0055] Having thus described certain particular embodiments of the invention, it is understood that the invention defined by the appended claims is not to be limited by particular details set forth in the above description, as many apparent variations thereof are contemplated. Rather, the invention is limited only be the appended claims, which include within their scope all equivalent devices or methods which operate according to the principles of the invention as described.
|
An actuator with an anti-drool valve is provided for attaching to or mounting on an aerosol container. Aerosol actuators, and more recently trigger actuated aerosol actuators, may include a manifold which fits to or communicates with a valve on an aerosol container or can. Aerosol containers or cans typically contain a propellant such as a compressed gas or a volatile hydrocarbon. The contents of the container, along with the propellant, are held in the container by a container valve.
| 1
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Japanese Patent Application Nos. 2003-193031 and 2004-018655, which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a polyamideimide resin, a method for producing the polyamideimide resin, a polyamideimide resin composition, a film-forming material and an adhesive for electronic parts using the polyamideimide resin or polyamideimide resin composition.
[0004] 2. Description of the Related Art
[0005] Polyamide resins, polyamideimide resins and polyimide resins have been used in recent years in the fields of electronic materials in place of epoxy resins as heat-resistant resins being excellent in heat resistance, electric characteristics, adhesivity, hygroscopicity and workability. However, irrespective of their excellent characteristics as described above, these resins are high elastic so as to occur poor adhesivity to the substrate when used as coating films due to their highly rigid resin structure while softness and bendability of hardened films are poor due to their low flexibility.
[0006] For solving these problems, there is proposed an aromatic polyamide-acrylonitrile-butadiene copolymer that is made to have a low elastic modulus by giving the resin flexibility by using acrylonitrile-butadiene having carboxylic acid terminals (cf. Japanese Patent Application Laid-Open Nos. 02-245032 and 03-47836). The polyamide polymer contained in the polyamide resin has polymer framework given flexibility by a structural unit derived from butadiene-containing dicarboxylic acid. Therefore, a coating film thus obtained has low elasticity and hence can have significantly improved adhesivity and flexibility.
[0007] However, the polyamide resin disclosed in the conventional arts involves a problem of causing a decrease of insulation characteristics due to remaining ionic impurities derived from a phosphorus-base condensing agent in the polymer since the polymer is polymerized in the presence of the phosphorus-base condensing agent.
SUMMARY OF THE INVENTION
[0008] Accordingly, it is an object of the invention to provide a resin and resin composition having low elasticity and being excellent in flexibility while being excellent in heat resistance, electric characteristics and adhesivity, as well as a film-forming material comprising the resin or resin composition, and an adhesive for electronic parts.
[0009] The present inventors have noticed the polyamideimide resin having excellent properties such as heat resistance, low hygroscopicity and excellent electric characteristics, particularly excellent insulation characteristics, as compared with polyamide resins.
[0010] The inventors have investigated to use aromatic isocyanate compounds as starting materials for suppressing eliminated components from being formed in the polymerization process to reduce the content of the impurities in the polymer. The aromatic isocyanate compound is known to form various bonds by reacting with various nucleophiles due to its high reactivity. By heating, an imide compound is obtained from a reaction between the aromatic isocyanate compound and an acid anhydride, and an amide compound is obtained from a reaction between the aromatic isocyanate compound and a carboxylic acid.
[0011] The present inventors have applied the reactions described above to a reaction of an acid dianhydride and an acrylonitrile-butadiene having terminal carboxylic acids with respect to an aromatic diisocyanate, and have found that it is possible to produce the polyamideimide resin that is excellent in flexibility while suppressing eliminated components from being formed in the polymerization process to reduce the content of impurities in the polymer. Thus, the present invention has been completed based on these studies.
[0012] According to an aspect of the present invention, there is provided a polyamideimide resin comprising a structural unit represented by the following general formula (1) and at least one of the structural unit represented by the following general formula (2) and the structural unit represented by the following general formula (3), and containing a polyamideimide copolymer with a number average molecular weight of 2000 to 50000. Wherein the number k of the structural unit represented by the general formula (1), the number m of the structural unit represented by the general formula (2), and the number n of the structural unit represented by the general formula (3) contained in the polyamide resin satisfy the relation of 0<m/(k+m+n)≦0.1:
(wherein, Ar 1 and Ar 2 each represent an aromatic group that may be substituted)
(wherein, Ar 2 is defined as described above, and a, b and c each is an integer of 0 to 100 with the relations of the ratio a/b of 0/1 to 1/0, the ratio (a+b)/c of 1/0 to 0/1, and the sum (a+b+c) of 1 to 100)
(wherein, Ar 2 is defined as described above, and d is an integer of 1 to 100).
[0016] Since the copolymer contained in the polyamideimide resin of the present invention has a structural unit derived from the butadiene-containing dicarboxylic acid in the frame thereof, the elastic modulus of the resulting hardened resin decreases to make the resin to be excellent in adhesivity and flexibility. In addition, the resin is excellent in insulation characteristics and hygroscopic reflow characteristics as compared with the resin using the polyamide resin.
[0017] According to another aspect of the present invention, there is provided a method for producing the polyamideimide resin comprising the steps of obtaining the structural unit represented by the general formula (1) by imidation by a decarboxylation reaction between an aromatic diisocyanate represented by the following general formula (4) and an aromatic tetracarboxylic acid dianhydride represented by the following general formula (5); obtaining the structural unit represented by the general formula (2) by amidation by a decarboxylation reaction between an aromatic diisocyanate represented by the following general formula (4) and a dicarboxylic acid represented by the following general formula (6); and
obtaining the structural unit represented by the general formula (3) by amidation by a decarboxylation reaction between an aromatic diisocyanate represented by the following general formula (4) and a dicarboxylic acid represented by the following general formula (7):
OCN—Ar 2 —NCO (4)
(wherein, Ar 2 is defined as described above)
(wherein, Ar 1 is defined as described above).
(wherein, a, b and c are defined as described above)
(wherein, d is defined as described above)
[0023] According to the production method as described above, the amount of the phosphorus-base condensing agent to be used is reduced to enable lower hygroscopicity of the resin than the polyamide resin to be attained, since the highly reactive aromatic diisocyanate compound is used as a substance for obtaining an imide bond by permitting it to react with the aromatic tetracarboxylic acid dianhydride, and as a substance for obtaining an amide bond by permitting it to react with a butadiene-containing dicarboxylic acid. The amount of ionic impurities originating from the phosphorous-base condensing agent can be reduced in the polyamideimide resin to enable the insulation characteristics of the hardened resin to be suppressed from being lowered. Furthermore, since the resin becomes less hygroscopic as compared with the polyamide resin, the resin produced is also excellent in the hygroscopic reflow characteristics. Additionally, since a structural unit originating from the butadiene-containing dicarboxylic acid is formed in the polyamideimide copolymer frame in the hardened resin, flexibility may be imparted to the copolymer structure. Accordingly, the resulting hardened resin has a decreased elastic modulus and is excellent in adhesivity and flexibility.
[0024] According to still another aspect of the present invention, there is provided a polyamideimide resin in which the tetracarboxylic acid dianhydride is 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride represented by the following formula (8):
[0025] The polyamideimide resin containing the copolymer having the structure as described above is excellent in flexibility after hardening since the resin has good bendability. Containing many aromatic rings renders the resin excellent in laser processibility.
[0026] According to the present invention, there is further provided a polyamideimide resin composition comprising 10 to 100 parts by weight of an epoxy resin relative to 100 parts by weight of the polyamideimide resin.
[0027] According to a further aspect of the present invention, there is provided a coating film forming material and an adhesive for electronic parts comprising the polyamideimide resin or the polyamideimide resin composition.
[0028] The polyamideimide resin and polyamideimide resin composition of the present invention has a low elastic modulus and good adhesivity to a substrate while being excellent in electric characteristics and laser processibility.
[0029] The film-forming material and adhesive for electronic parts using the polyamideimide resin or polyamideimide resin composition may be favorably used for an adhesive film, interlayer insulation film, surface protective film, solder resist film or the like in printed circuit boards by taking advantage of the excellent characteristics as described above.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] The polyamideimide resin of the present invention contains a polyamideimide copolymer containing the structural unit represented by the general formula (1), and at least one of the structural unit represented by the general formula (2) and the structural unit represented by the general formula (3).
[0031] Ar 1 and Ar 2 in the general formula (1) are aromatic groups that may be substituted. Examples of the preferable aromatic groups include phenylene, naphthalene, tolylene, tolidine and diphenylmethane groups for Ar 1 , and biphenyl, benzophenone and naphthalene groups for Ar 2 . Examples of the preferable substituents include alkyl groups having a carbon number of 1 to 5 such as methyl and ethyl groups.
[0032] While a+b+c is 1 to 100 in the general formula (2), the value is preferably 5 to 90, more preferably 10 to 80. The value of a+b+c of less than 1 tends to fail in obtaining flexibility, while the value of a+b+c of exceeding 100 tends to decrease heat resistance and reactivity.
[0033] The ratio a/b is in the range of 1/0 to 0/1, preferably 1/0 to 1/4, and more preferably 1/0 to 2/3. The a/b ratio of 1/0 tends to decrease solubility of the resin, while the a/b ratio of 0/1 tends to improve heat resistance of the hardened resin.
[0034] The ratio (a+b)/c is in the range of 1/0 to 0/1, preferably 95/5 to 2/8, and more preferably 9/1 to 4/6. The ratio (a+b)/c of 0/1 tends to decrease electric resistance, while the ratio (a+b)/c of 1/0 tends to decrease heat resistance, solubility and adhesivity.
[0035] The polyamideimide resin of the present invention contains k, m and n structural units represented by the general formulae (1), (2) and (3), respectively, in the polyamideimide copolymer, in which k is an integer of no less than 1, and m and n are integers of no less than 0 (n and m are not simultaneously zero). The ratio m/(k+m+n) is in the range of 0 to 0.1 (not including zero), more preferably 0.01 to 0.07, and further preferably 0.02 to 0.05. Insulating property of the polyamideimide resin tends to be decreased when the ratio m/(k+m+n) exceeds 0.1, while compatibility with the epoxy resin decreases when the ratio is 0.
[0036] The resin containing 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride represented by the formula (8) in the structural unit in the general formula (1) is preferable considering flexibility and laser processibility. While the number average molecular weight of the polyamideimide resin of the present invention is in the range of 2000 to 50000, it is preferably 5000-40000, more preferably 6000 to 30000 and further preferably 8000 to 20000. Film characteristics such as heat resistance tends to decrease when the number average molecular weight is less than 2000, while the resin becomes hardly soluble in the reaction solvent when the molecular weight exceeds 50000, and therefor easy to remain insoluble during the synthesis process. As a result, the workability tends to become poor.
[0037] The number average molecular weight was measured by gel permeation chromatography (GPC), and was calibrated using the molecular weight of polyethyleneglycol (PEG) as standard.
[0038] Practically, HLC-8120 GPC (manufactured by TOSOH Corp.) was used for GPC with a column temperature of 40° C. and a pump flow rate of 0.4 mL/minutes. The detector used was an RI detector integrated in the GPC. The data was processed using a calibration curve of the standard PEG having known molecular weight (calibration at a molecular weight range of no less than 1000) to obtain a molecular weight calibrated by the molecular weight of PEG.
Column used: Super AWM-H+Super AWM-H+Super AW3000 Mobile phase: 10 mM LiBr+N-methylpyrrolidone Injection volume: 20 μl Sample concentration: 0.1% (w/w)
[0043] While the molecular weight distribution is usually in the range of 3.0 to 12.0, it is preferably in the range of 2.0 to 10.0, and more preferably in the range of 2.0 to 8.0.
[0044] The molecular weight distribution is defined as the ratio (Mw/Mn) of the number average molecular weight (Mn) determined by above GPC to the weight average molecular weight (Mw).
[0045] The polyamideimide resin of the present invention is produced by the steps comprising: obtaining the structural unit represented by the general formula (1) by imidation by a decarboxylation reaction between the aromatic diisocyanate represented by the general formula (4) and the aromatic tetracarboxylic acid dianhydride represented by the general formula (5); obtaining the structural unit represented by the general formula (2) by amidation by a decarboxylation reaction between the aromatic diisocyanate represented by the general formula (4) and the butadiene-containing dicarboxylic acid represented by the general formula (6); obtaining the structural unit represented by the general formula (3) by amidation by a decarboxylation reaction between the aromatic diisocyanate represented by the general formula (4) and the butadiene-containing dicarboxylic acid represented by the general formula (7); and copolymerizing the obtained structural units.
[0046] Examples of the aromatic diisocyanate represented by the general formula (4) include phenylene-1,4-diisocyanate, phenylene-1,3-(diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenylether diisocyanate, 4,4′-[2,2-bis(4-phenoxyphenyl)propane]diisocyanate, naphthalene-1,5-diisocyanate, naphthalene-1,6-diisocyanate, biphenyl-4,4′-diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate and 2,2′-dimethylbiphenyl-4,4′-diisocyanate, but not restricted thereto. Each of these aromatic diisocyanates may be used alone, or as a combination of a plurality of them.
[0047] Tolylene diisocyanate is particularly preferable in consideration of a balance among mechanical characteristics, solubility and cost performance.
[0048] Examples of the aromatic tetracarboxylic acid dianhydride represented by the general formula (5) include pyromellitic acid dianhydride, 3,3′,4,4′-benzophanone tetracarboxylic acid dianhydride, 3,3′4,4′-oxydiphthalic acid dianhydride, 3,3′4,4′-sulfonyldiphthalic acid dianhydride, 3,3′,4,4′-biphenyl tetracarboxylic acid dianhydride, 1,2,5,6-naphthalene tetracarboxylic acid dianhydride, 2,3,5,6-pyridine tetracarboxylic acid dianhydride, 1,4,5,8-naphthalene tetracarboxylic acid dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride and butane tetracarboxylic acid dianhydride, but not restricted thereto. Each of them may be used alone, or as a combination of a plurality of them.
[0049] 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride that is excellent in laser processibility is preferable among them since it exhibits bendability due to its ether bond.
[0050] Tricarboxylic acid anhydrides (such as trimellitic acid anhydride, 3,3,4-benzophenone tricarboxylic acid anhydride and 2,3,4′-diphenylether tricarboxylic acid anhydride) may be used in addition to the dianhydrides above, if necessary.
[0051] The dicarboxylic acids represented by the general formulae (6) and (7) are acrylonitrile-butadiene copolymer and butadiene having carboxylic groups at both terminal thereof. The number average molecular weight of these compound is preferably 1000 to 5000, and compounds known in the art may be used.
[0052] Examples of the acrylonitrile-butadiene copolymer represented by the general formula (6) and having carboxylic groups at both terminals include Hycar-RLP series polymers (for example CTBN 1300×8, CTBN 1300×13, CTBN 1300×31 and CTBNX 1300×9) manufactured by Ube Industries Ltd., but not restricted thereto.
[0053] Examples of the butadiene polymers represented by the general formula (7) and having carboxylic groups at both terminals include Nisso-PB series polymers (for example C 1000) manufactured by Nippon Soda Co., and Hycar-RLP series polymers (for example CTB 2000×162) manufactured by Ube Industries Ltd., but not restricted thereto.
[0054] Each of these polymers may be used alone, or as a combination of a plurality of them.
[0055] Aliphatic dicarboxylic acids (such as succinic acid, glutaric acid, adipic acid, azelaic acid, decane dicarboxylic acid, dodecane dicarboxylic acid and dimer acids), and aromatic dicarboxylic acids (isophthalic acid, terephthalic acid, phthalic acid and naphthalene dicarboxylic acid) may be used in addition to the dicarboxylic acids above, if necessary.
[0056] The total amount of the dicarboxylic acid represented by the general formula (6) or (7) to be compounded is preferably 20 to 80% by weight, more preferably 30 to 70% by weight, and further preferably 40 to 60% by weight relative to the polyamideimide copolymer. Adhesivity and flexibility tend to decrease when the amount to be compounded is less than 20% by weight, while heat resistance tends to be deteriorated when the amount of blending exceeds 80% by weight.
[0057] In the present invention, the blending ratio between the aromatic diisocyanate and aromatic tetracarboxylic acid dianhydride, and the blending ratio between the aromatic diisocyanate and dicarboxylic acid for synthesizing the polyamideimide copolymer are determined by the ratio of the total number of the isocyanate groups to the total number of the acid anhydride group and the carboxylic groups in dicarboxylic acid. This ratio is preferably 0.7 to 1.3, more preferably 0.8 to 1.2, and further preferably 0.9 to 1.1. It becomes rather difficult to sufficiently increase the molecular weight of the resin when the ratio is less than 0.7 or exceeds 1.3.
[0058] The polyamideimide copolymers of the present invention having the structural units represented by the general formulae (1), (2) and (3) may be obtained by simultaneously polymerizing the aromatic diisocyanate, aromatic tetracarboxylic acid dianhydride and dicarboxylic acid; or may be produced by reacting an excess amount of the aromatic diisocyanate with the aromatic tetracarboxylic acid dianhydride or dicarboxylic acid to obtain a polyimide or polyamide oligomer having isocyanate groups at the terminals, followed by polymerization by adding remaining aromatic tetracarboxylic acid dianhydride or dicarboxylic acid.
[0059] High polar, aprotic solvents such as NMP (N-methylpyrrolidone), DMF (N,N-dimethylformamide), DMAc (N,N-dimethylacetamide) and DMSO (dimethylsulfoxide) are preferably used as an organic solvent for synthesis of polyamideimide copolymer in the present invention. Aliphatic hydrocarbons such as cyclohexane, pentane and hexane, aromatic hydrocarbons such as benzene, toluene and chlorobenzene, ethers such as THF (tetrahydrofuran), diethylether and ethyleneglycol diethylether, ketones such as acetone, methylethyl ketone and 4-methyl-2-pentanone, and esters such as methyl propionate, ethyl acetate and butyl acetate may be also used as long as reaction substrates and target products are sufficiently soluble in these solvents. These solvents may be used as a mixture.
[0060] The amount of these organic solvents to be used is preferably 0.8 to 5 times (by weight) of the polyamideimide resin to be formed. A proportion of less than 0.8 times causes an excessively high concentration of the polymer in the synthesis process, making it difficult to perform stirring and hence synthesis, while a proportion of exceeding 5 times tends to decrease the reaction speed.
[0061] The reaction temperature for obtaining the polymer is usually 80 to 210° C., preferably 100 to 190° C., and more preferably 120 to 180° C. While the temperature may be constant from the start to the end of the reaction, the temperature may be low at the initial stage of the reaction with a temperature increase thereafter. A reaction temperature of below 80° C. makes the reaction speed low, which causes an excessively long reaction time possibly leading to insufficient molecular weight, while a temperature exceeding 210° C. tends to form a gel during the reaction.
[0062] The reaction time is usually 1 to 10 hours, preferably 2 to 5 hours, by taking the progress of the polymerization into consideration.
[0063] A catalyst may be added in the reaction system, if necessary. Examples of the catalyst available include tertiary alkyl amines such as N,N,N′,N′-tetramethyl-1,3-butanediamine, triethylamine and tributylamine; condensed cyclic amines such as 1,4-diazabicyclo[2.2.2]octane and 1,8-diazabicyclo [5.4.0]unde-7-ene; phosphorous compounds such as 1-phenyl-2-phosphorene-1-oxide and 3-methyl-1-phenyl-2-phosphorene-1-oxide; and metals such as alkali metals, alkali earth metals, tin, zinc, titanium and cobalt.
[0064] The polyamideimide resin composition of the present invention contains 100 parts by weight of the polyamideimide resin of the present invention, and 10 to 100 parts by weight of an epoxy resin. Solvent resistance, adhesivity and anti-hygroscopic reflowability of the resulting hardened resin composition may be improved by using the epoxy resin. The amount of the epoxy resin to be used is 10 to 100 parts by weight, preferably 20 to 90 parts by weight, and more preferably 30 to 80 parts by weight, relative to 100 parts by weight of the polyamideimide resin.
[0065] The solvent resistance and anti-reflowability of the hardened resin tend to be decreased when the amount of the epoxy resin is less than 10 parts by weight, while storability, heat resistance and adhesivity of the hardened resin tend to decrease when the amount of the epoxy resin exceeds 100 parts by weight.
[0066] Examples of the epoxy resin available in the present invention include bisphenol A epoxy resins such as Epicron 840, 840-S, 850, 850-S, 860, 1050, 1055, 3050, 4050, AM-020-P and AM-030-P; bisphenol F epoxy resins such as Epicron 830, 830-S and 835; cresol novolac epoxy resins such as Epicron N-660, N-665, N-673, N-680, N-660-LE and N-665-LE; phenol novolac epoxy resins such as Epicron N-740, N-770, N-775, N-740-80M and N-770-70M; and flexible epoxy resins such as Epicron TSR-960, TSR-601 and 1600-75×(all manufactured by Dainippon Ink and Chemicals, Inc.); and bisphenol A epoxy resins such as Epicoat 825, 827, 828, 828EL, 828×A, 834, 1001, 1002, 1003, 1055, 1004, 1004AF, 1007, 1009 and 1010 manufactured by Japan Epoxy Resins Co.,Ltd. However, the epoxy resin is not restricted thereto. Each of the epoxy resins may be used alone, or as a combination of at least two of them.
[0067] A hardening agent may be added to the polyamideimide resin composition of the present invention. Known hardening agents used for epoxy resins may be used, and examples of them include amines, polyamide resins, novolac resins and acid anhydrides.
[0068] Examples of the amines include aromatic polyamines such as 4,4′-diaminodiphenyl methane, 4,4′-diaminodiphenyl ether and p-phenylenediamine; aliphatic polyamines such as diethylene tri amine, triethylene tri amine, meta-xylene diamine and bis(4-amino-3-methylcyclohexyl)methane; piperidine, pyrrolidine, imidazole and their derivatives; and secondary and tertiary amines such as triethylamine, N,N,N′,N′-tetramethyl hexamethylenediamine, 1,8-diazabicyclo[5.4.0]undecene, 1,4-diazabicyclo [2.2.2]octane and picoline.
[0069] Examples of the polyamide resin include reaction products of aliphatic dicarboxylic acids, dimer acids and trimer acids with polyamines.
[0070] Examples of the novolac resins include low molecular weight resin compositions obtained by condensation of phenol and formaldehyde, and condensation of a mixture of phenol, cresol and dihydroxybenzene with formaldehyde.
[0071] Examples of the acid anhydride include acid anhydride such as phthalic acid anhydride, trimellitic acid anhydride, pyrromellitic acid anhydride, benzophenone tetracarboxylic acid anhydride, methyl tetrahydrophthalic acid anhydride and succinic acid anhydride, and mixtures thereof.
[0072] The method for adding the epoxy resin to the polyamideimide resin of the present invention is not particularly restricted. For example, the epoxy resin to be added is previously dissolved in the same solvent as the solvent used for producing the polyamideimide resin, and the solution is added to the polyamideimide resin solution. Alternatively, the epoxy resin may be directly added to the polyamideimide resin.
[0073] Organic and inorganic fillers, surfactants such as defoaming agents and leveling agents, coloring agents such as dyes and pigments, heat stabilizers, anti-aging agents, fire retardants and slip agents may be added to the polyamideimide resin and polyamideimide resin composition of the present invention for improving workability of coating and film characteristics before and after forming the coating film.
[0074] The polyamideimide resin and polyamideimide resin composition of the present invention are favorable to be used as film forming materials used for forming interlayer insulation films, surface protective films, solder resist films and adhesive films in printed circuit boards, and as adhesives for electronic parts.
EXAMPLES
[0075] While the invention is described in detail hereinafter with reference to examples, the invention is by no means restricted to these examples.
Example 1
[0076] Added in a 500 mL separable flask equipped with a stirrer, reflux column and nitrogen inlet tube were 8.88 g (2.5 mmol) of Hycar CTBN 1300×8 (made by Ube Industries Ltd.) as an acrylonitrile-butadiene copolymer having carboxylic groups at both terminals, 2.10 g (0.5 mmol) of Hycar CTB 2000×162 (made by Ube Industries Ltd.) as a butadiene copolymer having carboxylic groups at both terminals, and 66.2 g of N-methylpyrrolidone (abbreviated as NMP hereinafter), and the mixture was dissolved homogeneously by heating at 60° C. Added therein was 24.46 g (47 mmol) of 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (abbreviated as BSAA hereinafter) as an aromatic tetracarboxylic acid dianhydride and, after dissolving the compound, 8.71 g (50 mmol) of tolylene diisocyanate (a mixture of 2,4-substituted compound and 2,6-substituted compound, abbreviated as TDI hereinafter) as an aromatic diisocyanate was added. The mixture was heated to 170° C., and then stirred for 2 hours. The reaction was completed by confirming that absorption peaks of the isocyanate at 2270 cm −1 and of acid anhydride at 1854 cm −1 in the IR spectrum had been disappeared. The reaction system was cooled to room temperature in water bath after completing the reaction.
[0077] The reaction solution was diluted with NMP, and the polymer solution obtained was poured into methanol with vigorous stirring to allow the resin to precipitate. The precipitated resin was isolated by filtration. The resin obtained was further washed with methanol, and was dried at 60° C. for 48 hours using a hot-air circulating drier to obtain 36.6 g (yield 92%) of a resin powder.
[0078] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1778 cm −1 and 1726 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0079] The number average molecular weight and molecular weight distribution of the resin obtained were 12000 and 4.2, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 2
[0080] A resin powder (40.5 g, yield 92%) was obtained in the same manner as that of Example 1, except that 5.33 g (1.5 mmol) of Hycar CTBN 1300×8, 10.50 g (2.5 mmol) of Hycar CTB 2000×162, 72.71 g of NMP, 23.94 g (46 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0081] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0082] The number average molecular weight and molecular weight distribution of the resin obtained were 11000 and 3.5, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 3
[0083] A resin powder (43.8 g, yield 93%) was obtained in the same manner as that of Example 1, except that 8.88 g (2.5 mmol) of Hycar CTBN 1300×8, 10.50 g (2.5 mmol) of Hycar CTB 2000×162, 77.26 g of NMP, 23.42 g (45 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0084] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0085] The number average molecular weight and molecular weight distribution of the resin obtained were 10000 and 3.5, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 4
[0086] A resin powder (45.7 g, yield 91%) was obtained in the same manner as that of Example 1, except that 1.78 g (0.5 mmol) of Hycar CTBN 1300×8, 21.00 g (5.0 mmol) of Hycar CTB 2000×162, 82.0 g of NMP, 23.16 g (44.5 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0087] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0088] The number average molecular weight and molecular weight distribution of the resin obtained were 12000 and 4.0, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 5
[0089] A resin powder (53.5 g, yield 95%) was obtained in the same manner as that of Example 1, except that 8.88 g (2.5 mmol) of Hycar CTBN 1300×8, 21.00 g (5.0 mmol) of Hycar CTB 2000×162, 91.1 g of NMP, 22.12 g (42.5 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0090] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0091] The number average molecular weight and molecular weight distribution of the resin obtained were 13000 and 4.3, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 6
[0092] A resin powder (52.7 g, yield 95%) was obtained in the same manner as that of Example 1, except that 13.31 g (3.75 mmol) of Hycar CTBN 1300×8, 15.75 g (3.75 mmol) of Hycar CTB 2000×162, 89.84 g of NMP, 22.12 g (42.5 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0093] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0094] The number average molecular weight and molecular weight distribution of the resin obtained were 12500 and 4.5, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 7
[0095] A resin powder (60.7 g, yield 95%) was obtained in the same manner as that of Example 1, except that 17.75 g (5.0 mmol) of Hycar CTBN 1300×8, 21.00 g (5.0 mmol) of Hycar CTB 2000×162, 102.42 g of NMP, 20.82 g (40.0 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0096] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0097] The number average molecular weight and molecular weight distribution of the resin obtained were 15000 and 5.0, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 8
[0098] A resin powder (65.2 g, yield 95%) was obtained in the same manner as that of Example 1, except that 1.78 g (0.5 mmol) of Hycar CTBN 1300×8, 42.00 g (10.0 mmol) of Hycar CTB 2000×162, 72.70 g of NMP, 20.56 g (39.5 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0099] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0100] The number average molecular weight and molecular weight distribution of the resin obtained were 14000 and 4.1, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Example 9
[0101] A resin powder (68.7 g, yield 92%) was obtained in the same manner as that of Example 1, except that 8.88 g (2.5 mmol) of Hycar CTBN 1300×8, 42.00 g (10.0 mmol) of Hycar CTB 2000×162, 118.7 g of NMP, 19.52 g (37.5 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0102] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0103] The number average molecular weight and molecular weight distribution of the resin obtained were 17000 and 4.1, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Comparative Example 1
[0104] A resin powder (44.8 g, yield 92%) was obtained in the same manner as that of Example 1, except that Hycar CTBN 1300×8 was not used, and 21.00 g (5.0 mmol) of Hycar CTB 2000×162, 79.70 g of NMP, 23.42 g (45.0 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0105] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0106] The number average molecular weight and molecular weight distribution of the resin obtained were 11000 and 3.5, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Comparative Example 2
[0107] A resin powder (58.5 g, yield 94%) was obtained in the same manner as that of Example 1, except that 26.63 g (7.5 mmol) of Hycar CTBN 1300×8, 10.5 g (2.5 mmol) of Hycar CTB 2000×162, 72.70 g of NMP, 20.82 g (40.0 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0108] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0109] The number average molecular weight and molecular weight distribution of the resin obtained were 12000 and 3.5, respectively, as determined by GPC using polyethyleneglycol as a reference material.
Comparative example 3
[0110] A resin powder (40.5 g, yield 92%) was obtained in the same manner as that of Example 1, except that Hycar CTBN 1300×8 was not used, and 35.50 g (10.0 mmol) of Hycar CTB 2000×162, 97.5 g of NMP, 23.42 g (45.00 mmol) of BSAA and 8.71 g (50 mmol) of TDI were used.
[0111] The structure of the resin powder obtained was confirmed to be a desired polyamideimide resin from an IR spectrum, which showed peaks around 1780 cm −1 and 1730 cm −1 assigned to the imide group and a peak around 2240 cm −1 assigned to the nitrile group.
[0112] The number average molecular weight and molecular weight distribution of the resin obtained were 15000 and 4.0, respectively, as determined by GPC using polyethyleneglycol as a reference material.
[0113] The components and blending ratios thereof used in Examples 1 to 9 and Comparative Examples 1 to 3 are shown in Table 1.
TABLE 1 Acrylonitrile- butadiene Butadiene copolymer polymer having having carboxylic carboxylic Number average groups at groups at molecular both both weight/molecular Polymer Composition TDI BSAA terminals terminals weight k/ m/ n/ (mmol) (mmol) (mmol) (mmol) distribution (k + m + n) (k + m + n) (k + m + n) Example 1 50 47 2.5 0.5 12000/4.2 0.94 0.05 0.01 Example 2 50 46 1.5 2.5 11000/3.5 0.92 0.03 0.05 Example 3 50 45 2.5 2.5 10000/3.5 0.90 0.05 0.05 Example 4 50 44.5 0.5 5.0 12000/4.0 0.89 0.01 0.10 Example 5 50 42.5 2.5 5.0 13000/4.3 0.85 0.05 0.1 Example 6 50 42.5 3.75 3.75 12500/4.5 0.85 0.075 0.075 Example 7 50 40.0 5.0 5.0 15000/5.0 0.80 0.1 0.1 Example 8 50 39.5 0.5 10.0 14000/4.1 0.79 0.01 0.2 Example 9 50 37.5 2.5 10.0 17000/4.1 0.75 0.05 0.2 Comparative 50 45 — 5.0 11000/3.5 0.90 0.00 0.1 Example 1 Comparative 50 40 7.5 2.5 12000/3.5 0.80 0.15 0.05 Example 2 Comparative 50 40 10.0 — 15000/4.0 0.80 0.20 0.00 Example 3
Example 10
[0114] Added in 100 parts by weight of a resin fraction in the polyamideimide resin obtained in Example 1 were 60 parts by weight of an epoxy resin (bisphenol A epoxy resin, Epicron 840S, manufactured by Dainippon Ink and Chemicals Inc.), 34 parts by weight of a hardening agent (a phenol resin Tamanol P-180, manufactured by Arakawa Chemical Industries Ltd.) and an amine catalyst (Curesol C11Z, manufactured by Shikoku Chemicals Co.), and a polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained by diluting the mixture with N,N-dimethylacetamide.
Example 11
[0115] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 2 was used as the polyamideimide resin.
Example 12
[0116] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 3 was used as the polyamideimide resin.
Example 13
[0117] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 4 was used as the polyamideimide resin.
Example 14
[0118] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 5 was used as the polyamideimide resin.
Example 15
[0119] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 6 was used as the polyamideimide resin.
Example 16
[0120] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 7 was used as the polyamideimide resin.
Example 17
[0121] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 8 was used as the polyamideimide resin.
Example 18
[0122] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Example 9 was used as the polyamideimide resin.
Comparative Example 4
[0123] Added in 100 parts by weight of a resin fraction in a resin (type-0, manufactured by Tomoegawa Paper Co.) mainly comprising an aromatic polyamide-acrylonitrile-butadiene copolymer were 60 parts by weight of an epoxy resin (bisphenol A epoxy resin, Epicron 1055, manufactured by Dainippon Ink and Chemicals Inc.), a hardening agent (a phenol resin, Tamanol P-180, manufactured by Arakawa Chemical Industries Co.) and an amine catalyst (Curesol C11Z, manufactured by Shikoku Chemicals Co.), and a polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained by diluting the mixture with a mixed solvent of methylethyl ketone and N,N-dimethylacetamide.
Comparative Example 5
[0124] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Comparative Example 1 was used as the polyamideimide resin.
Comparative Example 6
[0125] 15 A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Comparative Example 2 was used as the polyamideimide resin.
Comparative Example 7
[0126] A polyamideimide resin composition containing 40% by weight of non-volatile fraction was obtained in the same manner as that of Example 10, except that the resin obtained in Comparative Example 3 was used as the polyamideimide resin.
[0127] The resin compositions obtained in Examples 10 to 18 and Comparative Examples 4 to 7 were tested as follows.
[heading-0128] (Preparation of Adhesive Films)
[0129] The polyamideimide resin composition obtained in Example 10 was applied on a polyethylene terephthalate film (with a thickness of 25 μm) one surface of which was treated with silicone, and an adhesive film with a thickness of 25 μm was prepared by drying at 120° C. for 10 minutes. Adhesive films were also prepared using the polyamideimide resin compositions obtained in Examples 11 to 18 and Comparative Examples 4 to 7.
[heading-0130] (Measurement of Elastic Modulus of the Adhesive Film)
[0131] After completely hardening the adhesive film obtained above by heating at 180° C. for 90 minutes, the elastic modulus was measured using a dynamic viscoelastometer (trade name DMS 120, manufactured by Seiko Instruments Co.). The heating rate was 10° C./minute.
[heading-0132] (Measurement of Adhesive Strength of Adhesive Film (ICP-TM-650 2.4.9))
[0133] The adhesive film obtained above was adhered on a copper side face of a bifacial substrate (polyamide/copper) by pressing, and was hardened by heating at 180° C. for 90 minutes. The film obtained was subjected to a 90° peeling test to measure the adhesive strength of the film.
[heading-0134] (Measurement of Volume Resistivity of Adhesive Film)
[0135] After completely hardening the adhesive film obtained above by heating at 180° C. for 90 minutes, a conductive paste was applied on the film as electrodes to measure the volume resistivity of the film.
[heading-0136] (Measurement of Hygroscopic Coefficient of Adhesive Film)
[0137] After completely hardening the adhesive film obtained above by heating at 180° C. for 90 minutes, the film was placed in a constant temperature-constant humidity environment (85% RH) at 85° C. for 48 hours, and thereafter the hygroscopic coefficient of the adhesive film was measured by the Karl-Fisher method.
[heading-0138] (High Humidity Bias Test of Adhesive Film)
[0139] Comb-shaped patterns with a line/space widths of 100 μm/100 μm were formed on a polyimide film, and a sample was prepared by adhering the adhesive film on the polyimide film. The insulation resistance of this sample was measured for 1000 hours under a condition of 60° C./95% RH while a direct current voltage of 15V was applied. The sample that maintained an insulation resistance of no less than 5×10 8 Ω for 1000 hours was evaluated as good (◯), the sample that showed a decrease of the resistance of below 5×10 8 Ω during the measurement was evaluated as relatively good (Δ), and the sample that showed a resistance of less than 5×10 8 Ω immediately after the start of the measurement was evaluated as poor (x).
[heading-0140] (Hygroscopic Reflow Test of Adhesive Film)
[0141] A three-layer test substrate was prepared using the adhesive film above. The test substrate was allowed to absorb moisture by standing it under a condition of 30° C./60% RH for 168 hours, and was allowed to pass through a reflow furnace (peak temperature 260° C.) three times thereafter. Foaming (swelling) in the substrate, if any, was confirmed by visual test, and the sample showing no foaming was evaluated as good (◯) while the foamed sample was evaluated as poor (x).
TABLE 2 High humidity bias test Interline resistance (Ω) Storage Adhesive Volume Hygro- After Modulus Strength Resistivity scopicity 1000 Hygroscopic Applicability (GPa) (kN/m) (Ω · cm) (%) Initial hours Evaluation Reflow Test Example 10 ◯ 1.5 0.9 2.0E+15 0.75 1.0E+13 1.3E+09 ◯ ◯ Example 11 ◯ 1.0 0.9 3.7E+16 0.73 1.0E+13 1.5E+09 ◯ ◯ Example 12 ◯ 0.8 0.9 1.8E+15 0.52 1.0E+13 1.0E+09 ◯ ◯ Example 13 ◯ 0.8 0.5 4.0E+16 0.50 1.0E+13 3.6E+09 ◯ ◯ Example 14 ◯ 0.5 0.7 2.0E+16 0.63 1.0E+13 2.0E+09 ◯ ◯ Example 15 ◯ 0.5 0.9 7.5E+14 0.55 1.0E+13 9.7E+08 Δ (500 H) ◯ Example 16 ◯ 0.4 1.0 3.6E+13 0.57 1.0E+13 8.0E+08 Δ (300 H) ◯ Example 17 ◯ 0.5 0.5 5.0E+16 0.61 1.0E+13 2.5E+09 ◯ ◯ Example 18 ◯ 0.4 0.5 1.0E+16 0.50 1.0E+13 1.0E+09 ◯ ◯ Comparative ◯ 0.4 1.2 1.0E+14 1.20 1.0E+12 <1.0E+6 X (Initial) X Example 4 Comparative X 0.5 0.5 5.0E+16 0.58 1.0E+13 2.0E+09 ◯ X Example 5 Comparative ◯ 0.4 1.0 5.0E+14 0.70 5.0E+12 <1.0E+6 X (Initial) ◯ Example 6 Comparative ◯ 0.4 1.5 8.0E+13 0.80 8.0E+11 <1.0E+6 X (Initial) ◯ Example 7
[0142] Table 2 shows that the polyamideimide resin compositions in the examples have the same levels of elastic modulus as those of the polyamide resin compositions in Comparative Example 4 and polyamideimide resin compositions in Comparative Examples 5 to 7, and have excellent adhesive strength to the substrate while insulation characteristics thereof are excellent with large volume resistivity. In addition, the polyamideimide resin compositions in the examples has lower hygroscopicity than that of the polyamide resin in the comparative example while the former is also excellent in high humidity bias characteristics and hygroscopic reflow characteristics.
[0143] This specification is by no means intended to restrict the present invention to the preferred embodiments set forth therein. Various modifications to the polyamideimide resin, the polyamideimide resin composition, the film-forming material and the adhesive for electronic parts, as described herein, may be made by those skilled in the art without departing from the spirit and scope of the present invention as defined in the appended claims.
|
The present invention provides a resin and a resin composition having low elasticity and being excellent in flexibility while being excellent in heat resistance, electric characteristics and adhesivity, a film-forming material comprising the resin or resin composition, and an adhesive for electronic parts. The resin of the present invention is a polyamideimide resin comprising a structural unit represented by the following general formula (1) and at least one of the structural unit represented by the following general formula (2) and the structural unit represented by the following general formula (3). The number k of the structural unit represented by the general formula (1), the number m of the structural unit represented by the general formula (2), and the number n of the structural unit represented by the general formula (3) contained in the polyamide resin satisfy the relation of 0<m/(k+m+n)≦0.1, wherein the resin contains a polyamideimide copolymer with a number average molecular weight of 2000 to 50000:
(wherein, Ar 1 and Ar 2 each represent an aromatic group that may be substituted)
(wherein, Ar 2 is defined as described above, and a, b and c each are an integer of 0 to 100 with the relations of the ratio a/b of 0/1 to 1/0, the ratio (a+b)/c of 1/0 to 0/1, and the sum (a+b+c) of 1 to 100)
(wherein, Ar 2 is defined as described above, and d is an integer of 1 to 100).
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus and method for improving the ballistic performance of ammunition round, and, more particularly, the firing sequence of a projectile from an ammunition round.
2. Description of the Prior Art
Telescoped caseless ammunition is comprised of a propellant charge having an axial bore or cavity, a projectile housed entirely within the axial bore of the propellant charge and a primer positioned aft of the projectile. When a telescoped round of caseless ammunition is loaded into the chamber of a gun, the projectile, being housed in a propellant charge, is not seated in the barrel of the gun as is the projectile of a round of conventional ammunition when in a gun chamber. Upon initiation of the primer of the telescoped round, the projectile is forced forward into a barrel of the gun and becomes seated in the barrel. During the time interval from initiation of the primer until the projectile is seated in the barrel of the gun, some of the gases of combustion from the primer and from the initiated propellant charge can escape through the barrel ahead of the projectile resulting in a loss of impetus. Although telescoped ammunition is more convenient to handle than conventional ammunition, it presents different, and often more difficult, design and firing problems.
The primer must perform the dual function of first launching the projectile and then causing the main propellant charge to ignite. If the ignition of the main charge occurs too early, much of the work generated by the burning main propellant charge is lost to gases which escape down the barrel before the projectile obturates the barrel entrance. Should ignition of the main propellant charge be delayed, projectile travel causes the free volume of the chamber to be effectively increased beyond a desired optimum and reduce impetus to the projectile. Therefore, the primer must be formed in a precise, highly reproducible fashion to achieve good performance with telescoped ammunition.
Previous attempts at controlling the ignition and the firing sequence of a telescoped ammunition round have involved the use of adjusting the burning rates or chemical properties of the explosive or propellant materials. For example, it is known to use a gas barrier which separates the propellant charge into a forward section and an aft section. The chemical composition of the gas barrier is such that it momentarily delays flow of hot combustion gas to the forward section of the propellant charge, thereby delaying the ignition of the forward section with respect to the aft section.
However, relying upon the chemical properties of a material makes manufacturing more difficult and expensive because such chemical properties must be accurately controlled to provide performance of the ammunition round within desired limits. Indeed, depending upon the reproducibility required, manufacturing of such ammunition rounds can become an undesirably critical process. Further, it is difficult to develop materials which can cause firing of an ammunition round within a desired time limit under varying temperature conditions. As is known, ambient temperature affects the speed of burning and other chemical reactions. Since ammunition may be required to perform under conditions varying from Arctic cold to desert heat, suitable reliability in chemically controlling an ignition sequence for a telescoped ammunition round has been difficult to achieve. These are some of the problems the invention overcomes.
SUMMARY OF THE INVENTION
This invention teaches using mechanical, rather than chemical, action to control the firing sequence of a telescoped ammunition round. As a result, there is a high degree of reproducibility of firing action over a broad range of temperatures. Further, the criticality of exactly reproducing the chemical composition of the propellants from batch to batch is reduced thus simplifying manufacture and reducing the cost of manufacture.
In accordance with an embodiment of this invention, a propellant charge means for supplying firing power for an ammunition round has an axial cavity wherein a control tube means selectively covers portions of the propellant charge means facing the axial cavity thereby putting a selected portion of the propellant charge in communication with the axial cavity through a firing opening. A projectile means is housed within the axial cavity and can be fired from the ammunition round. A primer means is positioned generally aft of the projectile means and provides a firing force as part of a firing sequence for firing the projectile means from the ammunition round. Sealing means provide a movable barrier between the primer means and the propellant charge means. The sealing means is positionable between a first condition separating the primer means and the propellant means, thus preventing ignition of the propellant means by the primer means, and a second condition permitting communication between the propellant means and the primer means through the firing opening thus permitting ignition of the propellant means by said primer means.
For example, the sealing means can include a piston which is movable, as a result of the firing of the primer means from a position blocking the firing opening through the control tube means to a position forward of the firing opening thus permitting communication from the primer means to the propellant means.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a longitudinal, partly sectional view of an ammunition round in accordance with an embodiment of this invention;
FIG. 2 is a sectional view taken along section line 2--2 of FIG. 1; and
FIG. 3 is a view of the aft portion of the ammunition round of FIG. 1 after the firing sequence has begun and the piston has been moved forward sufficiently to permit communication between a main propellant charge and a primer charge.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, an ammunition cartridge 10 includes a generally cylindrical main propellant charge 40 having a cylindrical, coaxial cavity 45 wherein is positioned a generally elongated, tapered projectile 20. Positioned aft of projectile 20 is a generally cylindrical piston 50 having a longitudinal axis aligned with the longitudinal axis of axial cavity 45. A rear access 52 is a recess in the aft face of piston 50 and contains a booster charge 13 for propelling piston 50 forward within axial cavity 45 which also causes corresponding forward motion of projectile 20 within axial cavity 45. A primer charge 12 is positioned aft of booster charge 13 and is fired to cause firing of booster charge 13. Control tube 30 is a generally cylindrical, hollow sheath which surrounds primer charge 12, booster charge 13 and a rearward portion of projectile 20. Control tube 30 is sized to fit snuggedly within axial cavity 45 of main propellant charge 40 and has four circumferentially spaced firing openings 31 adjacent to and closed by the outside surface of piston 50. Firing of primer charge 12 and booster charge 13 causes piston 50 to move forward of firing openings 31 and expose main propellant charge 40 to firing through firing openings 31.
This concept achieves performance repeatability in telescoped ammunition by physically separating the initial projectile acceleration and main propellant ignition function. Control tube 30 launches and guides projectile 20 toward the barrel of a firing gun and contains and confines the initial firing of primer charge 12 and booster charge 13 so that the start of the firing sequence occurs at a fixed volume thus increasing the impetus to projectile 20. After initial projectile acceleration, the ignition of main propellant charge 40 occurs through firing openings 31 when piston 50 has moved sufficiently forward within axial cavity 45 and firing openings 31 are in communication with axial cavity 45. Thus, main propellant charge 40 fires solely as a function of the forward travel position of piston 50. If desired, ignition of main charge 40 can be achieved by positioning an igniter charge 32 between main propellant charge 40 and piston 50 at firing openings 31. Igniter charge 32 provides a positive ignition of main propellant charge 40 in response to sufficient forward travel of projectile 20 and piston 50 within axial cavity 45.
Control tube 30 has four circumferentially spaced slots 33 extending aft from the forward most portion of control tube 30 to a position forward of the rear end of projectile 20. As a result, the forward portion of control tube 30 includes forwardly projecting fingers 34 bounded on each side by slots 33 (see FIGS. 1 and 2). Slots 33 are located in the wall of control tube 30 to minimize the pressure differential on the wall between main propellant charge 40 and booster charge 13 resulting from rapid pressurization of the main charge. Too great a pressure differential would cause control tube 30 to collapse and impede firing. For example, a typical steel control tube will start to buckle if the pressure differential exceeds about 4000 psi. An aluminum tube with the same geometry will collapse at around 1400 psi. A typical length of each of four slots 32 is about 0.75 inches. Another approach would be to fabricate the control tube from a frangible, combustible material. The material would have to be strong enough to support the projectile during boost and contain the main charge during initial ignition phase to assure repeatable and minimum ignition delay. Nevertheless, firing of main propellant charge 40 is done through firing openings 31 when openings 31 are unported by movement of piston 50, and is not controlled by the combustion of the control tube.
Aft of projectile 20, the interior opening of control tube 30 narrows to the diameter of piston 50 to provide a snug fit between control tube 30 and piston 50. This is desirable to prevent forward leakage of combustion gases. Radially outwardly extending flanges 35 from an exterior portion of control tube 30 adjacent firing openings 31 define a recess wherein igniter charge 32 is contained. The inner diameter of control tube 30 further narrows aft of piston 50 to provide a channel 36 connecting primer charge 12 to booster charge 13 so that booster charge 13 can be fired as a result of control tube 30 increases to provide a cavity for receiving primer charge 12.
Piston 50 is generally cylindrical with a flat forward face 53 which abuts against a flat rear face 22 of projectile 20. Rear recess 52 opens to the rear of piston 50 and extends axially forward within piston 50 toward forward face 53. Booster charge 13 is positioned within recess 52, but can also extend aft of piston 50. The rearmost portion of rear recess 52 has a slightly larger diameter than the forward most portion of recess 52 so that the rearmost wall portion of piston 50 is somewhat thinner and can form a skirt 51, which is forced radially outward when booster charge 13 fires thus sealing the outer wall of piston 50 against the inner wall of control tube 30 and preventing forward leakage of firing gases. The piston can be of many forms such as of a combustible material, of a plastic material, integral with projectile 20, or a separate component from projectile 20.
Projectile 20 is generally cylindrical with a tapered front tip 23 for improved aerodynamic performance. The rearward portion of projectile 20 has an outer diameter which snuggly fits within an inner diameter of control tube 30. To further secure projetile 20 within control tube 30, the rear portion of projectile 20 includes a circumferential groove 21 wherein is positioned a split ring retainer ring 11 which compresses upon insertion into control tube 30 and provides an outwardly biased force to provide a retaining force preventing projectile 20 from slipping within control tube 30. If desired, control tube 30 can have a circumferential, inwardly facing groove to receive retainer ring 11 thus providing an additional force securing projectile 20 within control tube 30. Retainer ring 11 is advantageously fabricated of a material which shears upon application at a predetermined force.
Main propellant charge 40 is bounded by a cylindrical hollow outer case 44 on the outside cylindrical surface and an inner case 42 on the inside cylindrical surface around a forward portion of axial cavity 45. Inner case 42 extends from the front of main propellant charge 40 aft along a portion of the length of fingers 34. The aft end of main propellant charge 40 between the control tube 30 and outer case 44 is sealed by a generally annular base 14. Similarly, the forward end of main propellant charge 40 between inner case 42 and outer case 44 is closed by a generally annular front seal 41. An aft portion of main propellant charge 40 is in communication with igniter charge 32.
Although piston 50 can be integral with projectile 20, having a separate piston and projectile facilitates the manufacture and positioning of piston 50 thus minimizing the effect of free volume variability. When designing the transverse cross section size of piston 50, it is desirable to keep it sufficient small so there is a reduction in the piston velocity at ignition and a reduction in the potential for volume variability should some ignition delay occur.
OPERATION
The firing sequence of ammunition cartridge 10 includes the firing of primer charge 12 by such means as a firing pin or an electric spark so that heat and shock waves are transmitted along channel 36 to booster charge 13 which then ignites. The sequential firing of primer charge 12 and booster charge 13 causes a pressure build up aft of piston 50. At a predetermined pressure retainer ring 11 is sheared and there is forward movement of piston 50 in a direction parallel to the axis of axial cavity 45 as guided by control tube 30. As a result of such forward movement of piston 50 there is also forward movement of projectile 20. The volume containing the combustion gases from primer charge 12 and booster charge 13 is well controlled by the action of skirt 51 sealing the volume so that hot gases do not escape forward between the outer wall of piston 50 and the inner wall of control tube 30.
After piston 50 has sufficient forward displacement so that skirt 51 is positioned forward of firing openings 31, igniter charge 32 is exposed to hot combustion gases through firing openings 31 and itself fires. For example, 0.650 inches is a typical displacement for piston 50 to expose igniter charge 32 to the flame temperature of the firing of booster charge 13. The firing sequence of ammunition cartridge 10 continues by the firing of main propellant charge 40 as a result of the firing of ignition charge 32. If there is no igniter charge 32, main propellant charge 40 fires when firing opening 31 are unported and communicate combustion gases to main propellant charge 40. Projectile 20 has a typical speed of about 175 feet per second when igniter charge 32 activates main propellant charge 40.
Projectile 20 leaves ammunition cartridge 10, it enters the barrel of a firing gun and there is a snug fit, well known in the art, between the outer surface of the projectile and the inner surface of the barrel so that the hot combustion gases cause by the firing of ammunition cartridge 10 further propel projectile 20 out of the barrel. This staged sequence of ignition provides an energetic, fast and reproducible ignition of main propellant charge 40 controlled by the precise positioning of the projectile during the initial boost phase.
Referring to FIG. 3, piston 50 as shown after firing of primer charge 12 and booster charge 13 and having moved forward sufficiently so that skirt 51 is forward of firing opening 31 and firing opening 31 is exposed to the hot combustion gases within the axial cavity 45 aft of piston 50. Projectile 20 has also moved forward the same distance that piston 50 has moved forward. Retainer ring 11 has remained positioned in groove 21 of projectile 20 and has been freed of engagement with control tube 30. Skirt 51 remains in contact with the inner surface of control tube 30 so that the combustion gases from the firing of primer charge 12 and booster charge 13 do not go into the vacated volume of axial cavity 45 aft of projectile 20. If this were to happen, the propelling force due to the firing of primer charge 12 and booster charge 13 would be diminished.
In accordance with an embodiment of this invention, projectile 20 can, for example, weigh 194.5 grams and have a diameter of 25 millimeters. In an embodiment including a separate piston 50, the booster charge 13 can be, for example, 1.23 grams black powder, the location of firing openings 31 can be 0.75 inch from the aft end of cartridge 10, piston 50 can have a diameter of about 0.375 to 0.50 inches and a length of about 0.65 inches, igniter charge 32 can be about 1.17 grams black powder and main charge 40 can be 50 grams CIL 5554 and 60 grams IMR 4350. When a separate piston 50 is not used, a typical charge for booster charge 13 is 1.23 grams black powder with firing openings 31 being located 0.5 inches from the rear end of ammunition cartridge 10, and the main charge being about, for example, 115 grams CIL 1391A. A typical material for inner case 42 is a canvas backed phenolic tube with a wall thickness of about 0.05. Outer tube 44 can have an outer diameter of about 1.755 inches and a length of 6.0 inches. Stainless steel is a typical material for outer case 44 and can have a wall thickness of about 0.02 inches. The control tube 30, base 14 and front seal 41 can be 17-4 stainless steel heat treated R "C" 42.
Various modifications and variations will no doubt occur to those skilled in the various arts to which this invention pertains. For example, the particular overlap of the control tube with the projectile may be varied from that disclosed herein. Similarly, the particular size and shape of the piston may be varied from that disclosed herein. These and all other variations which basically rely on the teachings through which this disclosure has advanced the art are properly considered in the scope of this invention.
|
This specification discloses an ammunition round and a method of firing the ammunition round. Consecutive and reproducible firing of a primer charge and a main propellant charge is accomplished as a result of the physical movement of a divider physically separating the primer charge from the main charge. Firing of the primer charge causes movement of the divider, initiates movement of a projectile within the ammunition round, and, when the combustion gases of the primer charge are in communication with the main propellant charge, causes firing of the main propellant charge.
| 5
|
CROSS-REFERENCE TO RELATED APPLICATION
The present invention is related to the copending patent application for a method for dismantling a natural gas holder filed concurrently herewith.
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The present invention relates to passive load support devices and more particularly it relates to a passive load support cradle having a semi-active constituent in its construction which allows load equalization when a number of similar cradles are utilized for supporting a load. Still more particularly, the cradles of the present invention are used in multiples to support the weight of large structures as they are being disassembled from the bottom while the load of the structure is alternately lifted by jacks and then supported by the cradles.
2. DESCRIPTION OF THE PRIOR ART
The present invention was designed for use during the dismantling of large gas holders weighing in excess of 3,000 tons. The gas holders are in the form of a vertical cylinder approximately 400 feet high and 250 feet in diameter supported by a multiplicity of columns disposed around the periphery of the enclosure shell. The dismantling procedure consists of lifting the gas holder enclosure by hydraulic jacks disposed at every other one of the support columns. The alternate columns are cut off at the bottom along with a portion of the adjacent shell of the gas holder enclosure so the jacks can be fitted under the columns to lift the weight of the holder. When the holder has been lifted, the remaining alternate columns are cut off slightly higher than the height of the support cradles of the present invention whereby the holder structure can be lowered onto the cradles disposed at every other column around the gas holder between the jacks. These cradles then carry the load until the support columns and adjacent enclosure shell where each of the jacks are disposed can be further cut away, approximately the extension length of the jacks, and the jacks reactivated to again lift the structure. Then, the columns, and adjacent enclosure shell at each of the support cradles and the lower periphery of the gas holder is removed approximately equal to the amount of the stroke of the jacks. The jacks are then lowered the length of their stroke until the holder again rests on the cradles. The process can be repeated until the whole gas holder has been disassembled from the bottom and the remaining structure has been lowered close enough to the ground whereby it can be dismantled by other means.
The problem that needed to be solved occurs when the tank is lowered by the jacks onto the support cradles. With the heavy weight and inexact methods utilized to cut off the bottoms of the columns, it is necessary to provide a means whereby it can be assured that each of the support cradles is carrying nearly an equal share of the weight of the whole tank and performs its function of supporting one of the columns. If the columns are cut off by acetylene gas torches resulting an uneven surfaces, the problem is exacerbated. It is necessary to provide a cradle which can accommodate a possibly uneven cut without the necessity of accurately machining the bottom of each of the cut off columns before proceeding to lower the load onto the cradles.
In view of this unique engineering problem, there is no known prior art to the cradles of the present invention except for completely passive, inert support blocks.
SUMMARY OF THE INVENTION
The present invention is a support cradle for load equalization. It includes a lower base member having at least one crib secured thereto with at least one layer of elastomeric material disposed in the crib with the lateral edges of the material constrained by the crib when said material is put under compression. A load bearing upper member is formed for cooperating with the base member and has a piston secured thereto formed for fitting into the crib in close fitting relation for bearing on the elastomeric layer.
OBJECTS OF THE INVENTION
It is therefore an important object of the present invention to provide a support cradle which has a semi-active member in its construction which allows a load to be imposed thereon whereby when a multiplicity of cradles are utilized to support the load, the load is equalized on the different cradles.
It is another object of the present invention to provide a cradle for supporting a load which allows for unevenness in the lower surface of the supported member whereby the load is distributed among a multiplicity of cribs having elastomeric load absorbing materials constrained therein which equalize the load among the multiplicity of cribs.
And it is yet a further object of the present invention to provide a unique active element construction for a load supporting cradle.
Other objects and advantages of the present invention will become apparent when the apparatus of the present invention is considered in conjunction with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective exploded view of a preferred embodiment of the support cradle of the present invention;
FIG. 2 is a cross section in side elevation of the support cradle of FIG. 1;
FIG. 3 is an end elevation in cross section of FIG. 2 taken along lines 3--3 of FIG. 2; and
FIG. 4 is a broken out enlarged view of the layer of materials denoted in FIGS. 2 and 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is made to the drawings for a description of the preferred embodiment of the present invention wherein like reference numbers represent like elements on corresponding views.
FIG. 1 illustrates the elements of a preferred embodiment of the present invention. There shown is a base member 11 having at least one crib 13 secured thereto. In the preferred embodiment, a pair of cribs are utilized which are disposed in spaced relation at opposite ends of the base member. Additional cribs could be utilized with three being particularly advantageous for providing three-point suspension and with four being the optimum for the largest load-carrying capacity in the smallest space. Each of the cribs has at least one layer of elastomeric material 15 disposed in the crib, and the crib constrains the lateral or peripheral edges of the material when the material is put under compression. In the preferred embodiment, the constraining cribs are hollow cylinders made from lengths of steel tube for the greatest strength, ease of manufacture, and lowest cost. For the particular application described in the preceding description of the prior art, sections of 12-inch outside diameter steel tube having a 11/4-inch wall thickness is used.
In the preferred embodiment, fabreeka is utilized as the elastomeric material 15. Fabreeka is a manufactured material composed of layers of tightly twisted, closely woven, light weight duck with each layer being impregnated with a special elastomeric compound containing mold and mildew inhibiting agents. The physical properties of fabreeka were designed for the reduction of impact shock, vibration, and structure-borne noise. The material is a commercially available product manufactured by Fabreeka Products Co., Inc. It will withstand loads between 10,000 and 20,000 psi before breakdown depending upon the size and thickness of the pad. When it is constrained within a crib, the load deflection curve is non-linear and therefore its compressive modulus varies with the load. In the same manner, its static spring rate varies with the loading. It has a high damping value of about four times that of natural rubber and 100 times that of steel. It has a hardness which combined with its limited compressibility affords a great degree of stability. It has a large dielectric strength and electrical resistivity, and is impervious to most oils and is resistant to the effects of steam, water, mildew and brine, as well as continuous temperature exposures between plus 200 and minus 65 degrees fahrenheit. It is sold in pads and molded shapes.
In the preferred embodiment, a multiple of layers of fabreeka 15 are utilized in the cribs 13 and are employed in a multiple of assemblies. Each assembly includes two layers of inch-thick fabreeka secured together with adhesive which in turn are secured to a metal plate 17. Three such assemblies per crib are utilized for the particular application described in the prior art. The metal plates are machined to closely fit inside the cribs and facilitate the distribution of pressure throughout the fabreeka compression assembly and act as separators within the crib enclosure. The fabreeka layers are smaller in diameter than the cribs so that the peripheral edges are spaced slightly from the walls of the cribs until the layers are compressed and expand in diameter until they contact the walls of the cribs.
The load bearing upper member 19 has one or more pistons 21 secured thereto formed for fitting into each crib 13 in a closely fitting male/female relation. The load bearing upper member and the lower base member 11 are steel bars with the former being made out of 6-inch plate, 13 inches wide by 28 inches long for the described application. Each piston is designed to transmit the load from the upper load bearing member to the fabreeka layers 15. The upper load bearing member and the lower base member are provided with safety blocks 23 which are secured to each respectively and formed for preventing excessive loading of the fabreeka by limiting the penetration of the pistons of the load bearing member into the cribs of the base member.
The preferred embodiment of the present invention also includes wedge means which are utilized for lifting the cradles vertically to engage the load they are to support and for preloading the cradle and the fabreeka. The wedge means includes a tapered surface 25 formed on the bottom surface of the lower base member 11 with guide means in the form of plates 27 which are secured to the edges thereof proximate the center of the base member. In the preferred embodiment, the wedge means also includes a first center guide 29 secured to the bottom surface of the base member at the thinner end thereof 31 and a pair of elongated independent wedges 33 which in use are driven under the base member 11 on both sides of the center guide means 29 between the edge guides 27.
A wedge guide or receiver plate 35 is also utilized which is placed on the support base which is a concrete pad 37 for the support columns of the gas holder. It is a solid support surface on which the cradle is placed. The wedge guide plate also includes a second center guide/divider 39 and two pair of edge guides 41, 43 disposed at opposite ends of the guide plate. The second center guide is disposed in the middle of the wedge guide plate so that it contacts the first center guide 29 on the bottom of the lower base member 11 when the two are engaged in close opposed proximity before the wedges 33 are driven into position under the base member on the wedge guide plate. The engagement of the center guides prevents the lower base member moving with the wedges on the wedge guide plate when wedges are forced under the lower base member (See FIG. 2). The rear of the two pair of edge guides 43, where the wedges are inserted, are also provided with locking means or wedge retainers to prevent wedge retraction movement. In the preferred embodiment, the locking means includes holes 45 formed in the rear edge guides 43 so that locking bars 47 can be inserted behind the wedges 33 after they have been driven in under the base member 11 so that the wedges do not slip backwards on the wedge guide plate 35 and are retained therein.
FIG. 2 illustrates in cross section the preferred embodiment of the cradle of the present invention. More readily observable from that view is the location and assembly of the upper load bearing plate 19 with its pistons 21 which project downward into the cribs 13 mounted on the base member. Also more visible are the safety blocks 23 which are disposed between the cribs and which contact each other before the fabreeka 15 is overloaded. The ultimate loading of the fabreeka in the cribs can be controlled by placing different thickness spacers 49 between the safety blocks. A brass plate 51 is disposed on top of the load bearing member to engage the rough surfaces of the support column I beam lower end after it has been cut off. It can also be seen that the wedge guide plate 35 is provided with a depending anchor 53 which stops it from moving on the support surface 37 while the wedges 33 are being driven in underneath the cradle from right to left. The anchor positions the wedge guide plate by the insertion of blocks 55 or spacers between the anchor 53 and the concrete support base 37 which supports the load.
Breakouts for FIG. 4 shown in FIGS. 2 and 3 and disclose a load centering means which is utilized for the cradle. It includes a flat steel plate 57 which is disposed underneath the wedge guide plate 35 and is mounted on top of a plywood pad 59 which is mounted on the concrete base support 37. The plywood pad absorbs imperfections and unevenness in the top surface of the support base. The two plates 37, 57 are separated by a sheet of ultra high molecular weight polyethylene 61 which is mounted on top of a thin, smooth, stainless steel sheet 63. A film of moly grease 65 is disposed between the polyethylene and the stainless steel plates providing a very slippery interface between the polyethylene and the stainless steel whereby the support cradle can be easily moved, even when loaded, for proper centering under the load.
Thus, it will be apparent from the foregoing description of the invention, in its preferred form, that it will fulfill all the objects and advantages attributable thereto. While it is illustrated and described in considerable detail herein, the invention is not to be limited to such details as have been set forth except as may been necessitated by the appended claims.
|
A support cradle for load equalization including a crib containing fabreeka material mounted on a lower base member and a piston disposed on the lower side of the upper load supporting member whereby the piston fits in the crib to carry the load on the fabreeka.
| 4
|
BACKGROUND OF THE INVENTION AND SUMMARY OF THE INVENTION
The present invention relates generally to a system for mining coal in underground mines wherein a drilling unit bores horizontal holes into a coal seam and a retrieval unit extracts auger flights from a previously drilled hole simultaneously and in conjunction with the drilling unit.
In the prior art and in the present invention auger mining machines of this type comprise an auger embodying a cutting head suitable to the thickness of the coal seam connected to and rotatably driven by a string of end connected, helixally veined auger sections driven from the machine by being rotated and urged longitudinally of the auger. The cutting head penetrates the coal seam and the mine coal is transported rearwardly from the cutting head along the auger string by the veins of the auger sections out of the hole cut by the cutting head to a conveyor which carries the coal away from the machine. As the cutting head is caused to penetrate into the hole, it is necessary to introduce auger sections into the string until the desired length of the auger string is reached to achieve the desired depth of the hole. After the cutting head has penetrated to the desired depth of the hole it must be withdrawn by removing auger sections until the cutting head is out of the hole. The machine as a whole is then moved laterally to another position where its auger can drill another hole generally parallel to the previously drilled hole. Heretofore the prior art has disclosed patents for various augers and systems for the mining of coal. Some of the patents of the prior art are listed as follows:
U.S. Pat. No. 3,682,261 Michael J. Bird, Aug. 8, 1972
U.S. Pat. No. 2,846,093 Neil W. Densmore, Aug. 5, 1958
U.S. Pat. No. 3,281,187 G. L. Adams, et al., Oct. 27, 1966
U.S. Pat. No. 5,695,016 Ronald C. Deeter, et al., Dec. 9, 1997
U.S. Pat. No. 3,698,768 John L. Delli-Gatti, Oct. 17, 1972
U.S. Pat. No. 4,264,106 Ronald C. Deeter, et al., Apr. 28, 1981
Typically, in the underground mining of coal a roadway is created in the mine of predetermined limited height and width and thus, the size and height of the augering apparatus becomes critical and the retrieval and storage of auger flights presents a storage problem. Heretofore, in augering machines for mining coal in underground mines a series of relatively deep parallel horizontal holes are drilled in the coal seam and when the drilling of one hole is completed the augering machine is moved over the mine floor to a next adjacent position for drilling an adjacent parallel hole. The auger drill string is detached from the chuck of the boring machine prior to the shifting of the machine to its new drilling position and the series of auger drill flights are stored in the completed hole or on the floor of the roadway until needed for use in the drilling of the next adjacent hole. The auger flights are transferred a section at a time for connection to the drill string during drilling of the adjacent hole. It has become customary practice to roll the heavy auger sections over the rough bottom or floor of the mine and to lift manually and rotate the auger sections to bring them in proper alignment with the drill chuck to enable attachment thereof to the drill string as the adjacent hole deepens. In some instances a string of auger flights is stored in the previous drilled hole and requires the use of a separate apparatus to retrieve and transfer the auger flights to the auger machine for use in drilling the next adjacent hole. Such a transfer mechanism for auger drills is disclosed in U.S. Pat. No. 2,846,093 issued to Neil W. Densmore on Aug. 5, 1958.
One object of the present invention is to provide a new and improved underground auger system comprising a drilling unit and a retrieval unit which are adjustably connected and provide for the continuous drilling of holes and simultaneous retrieval of auger flights from a previous drilled hole, thus increasing efficiency in the mining of the coal and more efficient storage and transfer of auger flights to the drilling unit. In addition, the drilling unit and retrieval unit are coupled in front and back preferably with dog-bone type connectors which assures consistent pillar widths (the center to center distance of the auger holes) and closer coupling distances and also reduces the stress induced into each unit's frame in the event of uneven alignment. The dog-bone connectors are interchangeable to allow adjustments to pillar widths and assure the drive chains of the drill unit and retrieval unit are parallel during operation.
U.S. Pat. No. 3,682,261 issued to Michael J. Bird on Aug. 8, 1972, discloses a tunnel boring machine with a carriage which slides along a track and the carriage includes a spindle for attachment to a boring auger and a power supply which drives the spindle and also drives an hydraulic ram which moves the carriage along the track. A winch assembly is also provided in conjunction with the spindle for retracting auger sections from the bored tunnel without moving the carriage. The invention does not provide or teach of an underground auger system comprising a drilling unit and retrieving unit which are adjustably connected and work simultaneously with each other.
Further, the present invention provides a crowd mechanism within the drill unit for movement of the carriage and results in crowding forward in connect ion with the rotation of the cutting head and gives the cutting head the ability to dig the bits into the coal seam and cut. The crowd mechanism comprises a chain and sprocket system coupled to hydraulic cylinders which gives a mechanical disadvantage, however, it allows the carriage to move twice the distance of the cylinder stroke. Guide bars keep the sprocket from wandering off of a track and reduces wear on the cylinder seals. Two hydraulic cylinders are used for moving the carriage in each direction (four per unit) and thread adjustments are provided under the carriage to allow adjustment for cylinder differences and chain wear. A second crowd mechanism is provided within the retrieval unit and comprises the same component parts and provides for the movement of the carriage forward and backward and with the rotation of the drive unit gives the string of auger flights the ability to rotate out of the drilled hole. Prior art does not teach or disclose crowd mechanisms with respect to drilling units or retrieving units.
U.S. Pat. No. 3,698,768 issued to John L. Delli-Gatti on Oct. 17, 1972, provides an augering machine which includes an auger string composed of a plurality of auger flights connected to each other and at the rearward of the string a rotary drive means. The connection of the auger flights is by means of a pin and socket joint and includes a locking means and an unlocking member. Typically, in the industry auger flights are provided with a male and female end with the male end adapted to fit the female end of another auger flight and a spring-loaded latch pin is provided to secure two auger flights together and allowing the removal from the drilled hole without coming apart. In removing auger flights from the hole it is necessary to disconnect each auger flight from the string of auger flights for storage and transferring the auger flights to the drilling unit. The present invention provides a front delatch mechanism disposed within the drill unit and retrieval unit which comprises a hydraulic cylinder, bar linkage, and a spring-loaded latch actuator bar and provides a new and improved means of lifting the latch pin on the auger flight to provide for disconnecting of each auger flight from the string upon their removal from the drilled hole. The prior art does not teach or disclose of such a front delatch mechanism.
The present invention further provides for a transfer arm located within the retrieval unit to move auger flights from a belly pan in the retrieval unit to a belly pan in the drill unit during operation and it also is used to move auger flights to and from a staging rack in the retrieval unit to the belly pans of the drill and retrieval units. The transfer arm comprises a telescoping arm attached pivotally to the retrieval unit at one end and with a fork at the other end to cradle the auger flights when lifting and moving the flights. Hydraulic cylinders are provided to raise and lower the transfer arm and to extend and retract the arm. A transfer arm is not disclosed or taught in any prior art.
Another object of the present invention is to provide a staging rack area disposed within the retrieval unit to allow for the loading, unloading, and storage of auger flights within the retrieval unit and to allow the auger flights to be moved to and from the belly pan in the retrieval unit and further to allow the auger flights to be ready and available to be picked up by the transfer arm. In operation the auger flights may be moved to and from the retrieval unit and the drilling unit by the transfer arm and may be moved to and from the belly pan of the retrieval unit to the staging rack allowing for great flexibility in locating the auger flights for each stage of operation. A drive cross shaft with sprockets at each end driven by a power source is provided together with a second set of sprockets, shaft, and transfer chains with rollers to move the auger flights to and from the storage area and the belly pan within the retrieval unit. The transfer chains are synchronized and chain attachments, side guides, adjustment means, and stops are provided to prevent the auger flights from rolling and twisting during movement and to insure proper alignment of the auger flights.
The present invention further provides leveling jacks and skids in the drill unit and the retrieval unit to facilitate moving the machine and setting the angle for extracting flights from previously drilled holes. Roof jacks are also provided with each unit to work in conjunction with the leveling jacks and skids to wedge the units between the roof and floor of the mine roadway providing stability during extracting and drilling operations.
Prior art discloses and teaches of various auger mining machines and retrieval and storage apparatus for auger flights. U.S. Pat. No. 3,281,187 issued to George L. Adams, et al. on Oct. 25, 1966, discloses and teaches of a dual augering mining machine with dual auger storage racks but does not provide or teach of an underground auger system such as the present invention with a drill unit and a retrieval unit which are adjustably connected and provide for the simultaneous drilling and removal of auger flights or of a transfer arm mechanism, staging rack, crowd mechanism and delatch mechanism as are provided in the present invention. Further U.S. Pat. No. 4,264,106 issued on Apr. 28, 1981, to Ronald C. Deeter, one of the inventors of the present invention, discloses an augering machine which embodies jacks and skids which permit ready maneuverability of the machine and a cross conveyor for conducting away mined material from the auger string which are also provided in the present invention. However, the invention does not provide or teach of an underground auger system comprising a drill unit adjustably connected with a retrieval unit, crowd mechanism, staging rack, transfer arm mechanism, or delatch mechanism as are provided in the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention reference should be made to the accompanying drawings wherein:
FIG. 1 is a perspective view of the present invention.
FIG. 2 is a plan view of the drill unit and retrieval unit of the present invention.
FIG. 3 is an elevation view of the drill unit and retrieval unit of the present invention.
FIG. 4 is a plan view of the drill unit crowd mechanism of the present invention.
FIG. 5 is an elevation view of the drill unit crowd mechanism of the present invention.
FIG. 6 is a plan view of the retrieval unit crowd mechanism of the present invention.
FIG. 7 is an elevation view of the retrieval unit crowd mechanism of the present invention.
FIG. 8 is a plan view of the interchangeable connecting link of the present invention.
FIG. 9 is an elevation view of the interchangeable connecting link of the present invention.
FIG. 10 is an elevation view of the transfer arm mechanism of the present invention.
FIG. 11 is a cross section view along line A—A of FIG. 10 of the present invention.
FIG. 12 is a cross section view along line B—B of FIG. 10 of the present invention.
FIG. 13 is an elevation view of the auger staging rack of the present invention.
FIG. 14 is an elevation view of the front delatch mechanism of the present invention.
FIG. 15 is an elevation view of an auger flight of the present invention.
FIG. 16 is a section view of an auger flight socket.
DETAILED DESCRIPTION OF THE DRAWINGS
Reference is now made to the drawings wherein the present invention is illustrated in detail and wherein similar components bear the same reference numeral throughout the several views.
FIG. 1 is a perspective view of the present invention 1 and illustrates a retrieval unit 20 , drill unit 76 , the retrieval unit staging rack loading area 49 , the retrieval unit staging rack storage area 50 , the retrieval unit staging rack staging area 51 , and auger flights 8 in position on the present invention 1 .
FIG. 2 is a plan view of the drill unit 76 and retrieval unit 20 and illustrates the drill unit crowd mechanism 2 , drill unit frame 3 , drill unit carriage 4 , drill unit propulsion unit 5 , drill unit drive chuck 6 , drill unit rotating means 7 , drill unit belly pan 9 , drill unit leveling jack 10 , drill unit skid 11 , drill unit roofjack 12 , drill unit conveyor 13 , and interchangeable connecting link 37 . The retrieval unit 20 , the retrieval unit crowd mechanism 21 , the retrieval unit frame 28 , the retrieval unit carriage 29 , the retrieval unit propulsion unit 30 , the retrieval unit drive chuck 31 , the retrieval unit rotating means 32 , the retrieval unit belly pan 33 , the retrieval unit leveling jack 34 , the retrieval unit skid 35 , the retrieval unit roofjack 36 , transfer arm mechanism 41 , retrieval unit staging rack 48 , drive cross shaft 56 , and retrieval unit staging rack power source 61 are further illustrated.
FIG. 3 is an elevation view of drill unit 76 and retrieval unit 20 of the present invention 1 and further illustrates a drill unit carriage 4 , drill unit drive chuck 6 , drill unit rotating means 7 , drill unit leveling jack 10 , drill unit skid 11 , drill unit roofjack 12 , drill unit conveyor 13 , and drive cross shaft 56 . Retrieval unit carriage 29 , retrieval unit propulsion unit 30 , retrieval unit drive chuck 31 , retrieval unit rotating means 32 , retrieval unit leveling jack 34 , retrieval unit roof jack 36 , and delatch mechanism 62 are further illustrated.
FIG. 4 is a plan view of the drill unit crowd mechanism 2 and further illustrates drill unit crowd mechanism sprocket 15 , drill unit crowd mechanism sprocket box 17 , drill unit crowd mechanism cylinder 18 and drill unit crowd mechanism guide bar 19 .
FIG. 5 is an elevation view of the drill unit crowd mechanism 2 and further illustrates drill unit carriage 4 , drill unit crowd mechanism chain 14 , drill unit thread chain adjuster 16 , drill unit crowd mechanism sprocket box 17 , drill unit crowd mechanism cylinder 18 , drill unit crowd mechanism guide bar 19 .
FIG. 6 is a plan view of the retrieval unit crowd mechanism 21 and further illustrates retrieval unit crowd mechanism sprocket 23 , retrieval unit crowd mechanism sprocket box 25 , retrieval unit crowd mechanism cylinder 26 , and retrieval unit crowd mechanism guide bar 27 .
FIG. 7 is an elevation view of the retrieval unit crowd mechanism 21 and further illustrates retrieval unit crowd mechanism chain 22 , retrieval unit thread chain adjuster 24 , retrieval unit crowd mechanism sprocket box 25 , retrieval unit crowd mechanism cylinder 26 , retrieval unit crowd mechanism guide bar 27 , and retrieval unit carriage 29 .
FIG. 8 is a plan view of the interchangeable connecting link 37 and further illustrates drill unit frame 3 , retrieval unit frame 28 , and connecting link pin 38 .
FIG. 9 is an elevation view of the interchangeable connecting link 37 and further illustrates the connecting link cap 39 , connecting link latch 40 .
FIG. 10 is an elevation view of the transfer arm mechanism 41 and illustrates the retrieval unit frame 28 , transfer arm tubing 43 , transfer arm cylinder 44 , transfer arm lift cylinder 45 , transfer arm fork 46 , and transfer arm roller 47 .
FIG. 11 is a cross section view along line A—A of FIG. 10 and further illustrates transfer arm tubing 43 , transfer arm cylinder 44 .
FIG. 12 is a cross section view along line B—B of FIG. 10 and further illustrates transfer arm tubing 43 and transfer arm roller 47 .
FIG. 13 is an elevation view of the retrieval unit auger staging rack 48 and further illustrates the transfer arm fork 46 , retrieval unit staging rack loading area 49 , retrieval unit staging storage area 50 , retrieval unit staging rack staging area 51 , staging chain attachment 53 , auger staging stop 54 , staging chain takeup 55 , drive cross shaft sprocket 57 , staging rack side guide 58 , staging chain rollers 59 and staging drive chain 60 .
FIG. 14 is an elevation view of front delatch mechanism 62 and further illustrates delatch plate 63 , delatch plate clevis 64 , delatch linkage 65 , delatch arm 66 , delatch arm clevis 67 , delatch pin 68 and delatch cylinder 69 and delatch spring 70 .
FIG. 15 is an elevation view of an auger flight 8 and further illustrates auger shank 74 and auger socket 75 .
FIG. 16 is a section view of an auger flight socket 75 and further illustrates an auger flight pin 71 , an auger latch lever 72 , and an auger latch spring 73 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 through 16, the preferred embodiment of the present invention comprises a drill unit disposed with a drive, a frame, a carriage moveable on the frame, a propulsion unit with drive chuck and means on said frame and carriage for rotating a cutting head driven by a string of auger flights, a crowd mechanism to move the carriage on the frame and advance the cutting head driven by a string of auger flights for drilling a parallel horizontal hole, a front delatch mechanism disposed on the drill unit to engage the latch pin lever of an auger flight to disengage the auger flight from the string of auger flights in the drilled horizontal parallel hole, a belly pan disposed in the drill unit and adapted to cooperate with a transfer arm and to accept and receive auger flights for the connection and addition of the auger flights to the string of auger flights, leveling jacks, skids and roof jacks disposed on the drill unit to facilitate moving and stabilizing the unit and setting the angle for drilling the horizontal parallel hole, a conveyor means disposed at the operation end of the drill unit to remove the mined substance away from the drill unit, and an activating means to actuate the drill unit. Preferably, the propulsion unit is a Mannesmann Rexroth motor (an hydraulic fixed displacement motor) using petroleum based fluid at high pressure to generate the rotation and torque input necessary for drilling of the hole. The crowd mechanism preferably comprises four chains attached at one end to the frame of the drill unit each of which transverse a sprocket and at the other end of each chain disposed to attach to threaded adjusters on the carriage with the sprockets adapted to slideably accept each of the chains and sprocket boxes disposed between the sprockets and threaded adjusters and with a cylinder to move the sprocket box within guide bars on the frame to move the carriage on the frame of the drill unit toward or away from a drilled hole. Preferably four cylinders, four chains, and four sprocket boxes are provided with two of the cylinders to provide the thrust or forward force on the carriage and two of the cylinders to provide the pull or reverse force on the carriage. Preferable activating means to activate the movement of the crowd mechanism are hydraulic joysticks. Preferably the front delatch mechanism comprises a plate, with devices adapted to pivotally accept a linkage where the linkage has two ends adapted to attach to and pivot on the devices at the plate on one end and attach to and pivot on a delatch arm disposed at the other end with a delatch arm with a plurality of devices at one end and adapted to attach to the linkage and the other end adapted to engage the latch lever of the auger flight to disconnect the auger flight from the string of auger flights and pins to secure the linkage to the devices with an hydraulic cylinder and activating means disposed between the frame of the linkage to move the delatch arm toward and away from the latch lever of the auger flight and a spring disposed between the linkage and the delatch arm adapted to prevent the delatch arm from transferring actual loads to the linkage. The preferred activating means for the delatch mechanism are hydraulic joysticks.
Further, a retrieval unit comprising a drive, a frame, a moveable carriage on the frame, a propulsion unit with drive chuck and means on said frame and carriage for rotating a cutting head driven by a string of auger flights from a drilled parallel horizontal hole, a crowd mechanism to move the carriage on the frame and remove the cutting head driven by the string of auger flights from the parallel horizontal drilled hole, a front delatch mechanism disposed on said retrieval unit to engage the latch pin lever of an auger flight to disengage the auger flight from the string of auger flights in the drilled horizontal parallel hole, a belly pan disposed on the retrieval unit adapted to cooperate with a transfer arm and a transfer arm mechanism to move auger flights to and from a belly pan disposed on the retrieval unit to the belly pan disposed on the drill unit or to and from an auger staging rack disposed on the retrieval unit, an auger staging rack disposed to accept loading, storage, and unloading of auger flights and adapted to cooperate with the transfer arm mechanism to transfer auger flights and leveling jacks, skids, and roof jacks disposed on the retrieval unit to facilitate moving and stabilizing the retrieval unit and adjusting the angle for extracting flights from a string of auger flights in the drilled parallel horizontal hole; and an activating means to activate the retrieval unit. Preferably, the propulsion unit is a Mannesmann Rexroth motor using petroleum based fluid at high pressure to generate the rotation and torque input necessary for the removal of the string of auger flights from the parallel drilled hole. The crowd mechanism preferably comprises four chains attached at one end to the frame of the retrieval unit each of which transverse a sprocket and at the other end of each chain disposed to attach to threaded adjusters on the carriage with the sprockets adapted to slideably accept each of the chains and sprocket boxes disposed between the sprockets and thread adjusters and with a cylinder to move the sprocket box within guide bars on the frame to move the carriage on the frame of the retrieval unit toward or away from a drilled hole. Preferably four cylinders, four chains, and four sprocket boxes are provided with two of the cylinders to provide the thrust or forward force on the carriage and two of the cylinders to provide the pull or reverse force on the carriage. Preferable activating means to activate the movement of the crowd mechanism are hydraulic joysticks. Preferably the front delatch mechanism comprises a plate, with devices adapted to pivotally accept a linkage where the linkage has two ends adapted to attach to and pivot on the devices at the plate on one end and attach to and pivot on a delatch arm disposed at the other end with a delatch arm with a plurality of devices at one end and adapted to attach to the linkage and the other end adapted to engage the latch lever of the auger flight to disconnect the auger flight from the string of auger flights and pins to secure the linkage to the devices with an hydraulic cylinder and activating means disposed between the frame of the linkage to move the delatch arm toward and away from the latch lever of the auger flight and a spring disposed between the linkage and the delatch arm adapted to prevent the delatch arm from transferring actual loads to the linkage. The preferred activating means for the delatch mechanism is an hydraulic joystick.
The transfer arm mechanism disposed in the retrieval unit preferably comprises an arm with a fixed end and a telescoping end with a plurality of tubes and the fixed end with pivotally attached to the frame of the retrieval unit and adapted to point up and down from the frame with tubes adapted to slide within each other and telescope in and out of the arm to the belly pan of the drill unit or to the belly pan of the retrieval unit or to the staging rack of the retrieval unit. A double acting cylinder disposed in the arm extends and retracts the tubing in and out of the arm and is activated preferably by hydraulic joystick and a second double acting lift cylinder preferably with hydraulic joystick to activate the second double acting lift cylinder is disposed between the frame of the retrieval unit and the arm and raises and lowers the arm and a fork is disposed at the telescoping end of the arm and is adapted to pick up and receive auger flights for the movement of the flights.
A staging rack is disposed in the retrieval unit and comprises a loading area adapted to accept the loading and unloading of auger flights in the retrieval unit, a storage area to accept and store a plurality of auger flights, a staging area to receive auger flights from the loading area, storage area and the belly pan of the drill unit all of which cooperate with the transfer arm mechanism for the transfer of auger flights and the staging rack comprises preferably two staging chains connected end to end forming loops with two ends and disposed within and transversing the loading area, storage area, and staging area and adapted to transfer auger flights to and from the loading area, storage area, and staging area in an operation synchronized to provide even movement of the auger flights during transfer. Preferably a plurality of staging chains attachments are disposed on the staging chains to secure and position the auger flights in transfer and stops are provided and disposed at each end of the staging chain loop and encompass the staging chains to position the auger flights in the staging area, loading area and storage area to prevent the auger flights from rolling off of the retrieval unit. Staging chain take-ups are disposed on each chain and adjust slack in the chains and a drive cross shaft with sprockets preferably disposed between the frame of the retrieval unit and staging chains at each end of the staging chain loop and adapted to cooperate with and move the staging chains and with side guards disposed on the frame to cooperate with and guide and align the staging chains on the retrieval unit. Preferably the staging chains have rollers at each link of the staging chains provided to roll during the movement of the staging chains and reduce resistance and prevent sliding of the staging chains. The preferable chain is an U.S. Tsubaki conveying and elevating chain. Further, and preferably a drive chain connected end to end and disposed between the power source and the drive cross shaft rotates and drives the cross shaft to move the staging chains. Preferably the power source are low speed hi-torque hydraulic motors and the activating means to activate the auger staging rack preferably is an hydraulic joystick.
Interchangeable connecting links provided and disposed between the drill unit and retrieval unit preferably are removable and generally dogbone in shape bars which are adapted to pivotally connect the drill unit and retrieval unit by pins extending through the frame of each unit and the dogbone ends of the bars which reduces the stress reduced in each unit's frame in the event of uneven alignment. The dogbone connectors are interchangeable to allow adjustments to pillar widths and assure the drive chains of the drill unit and retrieval unit are parallel during operation. Preferably one interchangeable connecting link is provided in front and one interchangeable connecting link is provided in the back connecting the fronts and backs of the drill unit and retrieval unit accordingly.
Although the invention has been described in preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and numerous changes in the detail of construction and the combination arrangement of the parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.
|
An underground augering system comprising a drill unit adjustably connected to a retrieving unit by interchangeable and adjustable connectors to provide for simultaneous drilling of one hole and the removal of auger flights from a previous drilled hole, a crowd mechanism within each unit to move the drill and retrieval carriages to and from holes, a transfer arm to move auger flights to and from a staging rack within the retrieval unit and belly pan within the drill unit, and belly pan within the retrieval unit, a mechanism and staging rack for the storage of auger flights, and a delatch mechanism within the drill unit and retrieval unit to disengage the latch lever in an auger flight for removal of the auger flight from a string of auger flights.
| 4
|
FIELD OF THE INVENTION
This invention relates to methods for cleaving crystals in high vacuum and to deposit in-situ passivating layers on the cleaved crystal faces. It applies to a variety of technologies but is especially suitable for coating laser facets.
BACKGROUND OF THE INVENTION
The advent of the semiconductor laser followed the invention of the crystal laser and the gas laser both of which relied on a Fabry-Perot cavity, which is basically a pair of mirrors, to retain standing light waves for periods sufficient to stimulate light amplification. Semiconductor lasers rely also on a reflective cavity which is typically formed by mirrors on the ends of a semiconductor crystal. In the usual structure one mirror has high reflectivity (HR) and the other is partially transmitting, i.e low reflectivity (LR). In high performance lasers these mirrors perform the additional function of passivating the surfaces of the semiconductor device. The surfaces of the laser device that are exposed to high light flux are susceptible to degradation which has become a serious problem to overcome in producing devices with the extended lifetimes required in e.g. many communications applications. Facet degradation includes both catastrophic optical damage (COD) caused by intense optical flux and gradual erosion due to optically accelerated facet oxidation. The main cause of COD is local heating due to optical absorption and non-radiative recombination of optically generated carriers at the facets.
Problems of facet degradation have confronted laser device designers for years. Typically they become more critical as the device complexity and performance demands increase. The semiconductor materials used in advanced lightwave device technology are typically multilayer semiconductor crystals based on compounds of Ga, Al. and In with As, and P. The device structures have a variety of forms with both edge emitting and surface emitting configurations.
These high performance semiconductor lasers typically have facets that are produced by mechanically cleaving a semiconductor crystal. With appropriate applied force, crystals tend to fracture along crystallographic lines and the fracture face or facet is typically of near perfect quality. Efforts have been made to cut laser facets by various micromachining techniques such as laser machining, and by chemical processes such as etching. None of these have proved as effective, in terms of the quality of the facet, as mechanical cleaving.
Although mechanical cleaving produces a near perfect facet the newly exposed semiconductor surfaces begins to degrade instantly after cleavage, due to contaminants in the cleaving tool and exposure to air. Recognition of this degradation mechanism stimulated several reported approaches to overcome facet degradation. Among them are: ( i ) impurity induced lattice disordering ( IILD ) at the facet that increases the bandgap and thus reduces the optical absorption and facet heating ( see W. X. Zou et al, IEEE Photon. Technol. Lett 3, 400 (1991); ( ii ) growth of non-absorbing mirrors (NAM) on the laser facets (see H. Naito et al, J. Appl. Phys. 68, 4420 ( 1990) and M. Matsumoto et al, Jpn J. Appl. Phys. 32, L665 ( 1993); (iii ) facet treatment by sulfur or sulfur-based compounds (see S. Kamiyame et al, Appl. Phys. Lett. 58, 2595 ( 1991) and H. Kawanishi et al, Proceedings of the SPIE Symposium on Laser Diode Technology and Applications II, Vol. 1219, 309 (1990); and ( iv) cleaning or forming laser facets in high vacuum followed in situ by suitable passivation and LR/HR coating (see M.Gasser and E.E. Latta, U.S. Pat. No. 5,063,173 issued Nov. 5, 1991). All of these techniques have been used largely for the GaAs/AlGaAs/InGaAs material system. The IILD technique and the in-situ facet cleaning by plasma source are not suitable for phosphorus based materials like InP and InGaP due to physical damage caused by plasma ions.
Recent experience with 980 nm lasers for erbium-doped amplifiers has shown persistent degradation problems even in aluminum-free InGaAs/InGaP/GaAs lasers in which the InGaP cladding layer is lattice matched to GaAs. These lasers were expected to give an improved reliability and long term stability due to elimination of degradation resulting from oxidation of aluminum during fabrication. We find that these Al free lasers too are susceptible to facet degradation.
It is found that cleaving the crystal outside the vacuum even with immediate insertion of the cleaved crystals in the vacuum chamber is insufficient to avoid degradation of the semiconductor crystal facets. Even the use of known techniques, e.g. ( i ), ( ii ), and ( iii ) described above, that specifically address facet degradation, have generally been found inadequate.
The high vacuum cleaving technique (iv above), with in situ deposition of passivating layers, has proved promising. One difficulty with this technique is the mechanics and mechanical equipment required for cleaving the semiconductor crystals in an ultra-high vacuum apparatus. It requires a cleaving tool to be installed in the vacuum equipment with manipulation of the cleaving tool externally of the vacuum chamber through a vacuum seal. The mechanics of this process add to its complexity and reduce reliability. Improved methods of in-situ cleaving can significantly advance this technology.
SUMMARY OF THE INVENTION
We have discovered a cleaving technique that allows cleaving the semiconductor crystal in high vacuum and eliminates the need for manipulation of cleaving tools from the outside of the vacuum chamber through a vacuum seal. It relies on the properties of thermostatic metals, which bend or deflect proportionately with a temperature change. A moderate change in temperature activates the tool and cleaves the semiconductor bars. The overall cleaving fixture has several such tools for cleaving several bars at once. Once cleaving has occurred, through raising or lowering the temperature, a passivating coating is applied. The coating means, e.g. a beam flux of dielectric coating material, can be activated after cleaving or during cleaving.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic diagram of the facet degradation process;
FIG. 2 is a schematic representation of a typical laser used in the cleaving process of the invention;
FIG. 3 is a schematic representation of a cleaving tool using thermostatic principles;
FIG. 4 is a representation of a fixture with a plurality of thermostatic tools according to the invention; and
FIG. 5 is a representation of a alternative thermostatic tool arrangement operating in an alternative thermostatic mode.
DETAILED DESCRIPTION
Referring to FIG. 1, the degradation process of a typical laser facet is shown schematically. The facet of a laser usually has a large number of surface states due to facet oxidation or contamination when facets are formed in air. These states play a major role in the catastrophic optical damage (COD) mechanism. The maximum output optical power and the long term stability and reliability are limited by the COD.
The inventive technique can be practiced using the following methods.
First, semiconductor lasers involving compounds comprising In, Ga, Al, P, As, are fabricated on GaAs or InP wafers by known techniques. A schematic cross-section of a typical laser structure is shown in FIG. 2. An n-type GaAs substrate is shown at 21 with 0.5 μm of n-type GaAs buffer layer 22, and 1.2 μm n-InGaP cladding layer 23. A 60 Angstrom active InGaAs quantum well layer 24 is shown bounded by 0.1 μm GaAs confinement layers 25. The p-type cladding layer, 1.1 μm of p-InGaP, is shown at 26. A 60 Angstrom p-GaAs stop etch layer is provided at 27, the contact structure comprising SiO 2 layer 28, 1.2 μm p - InGaP mesa 30, 0.12 μm p + GaAs 31, Ti/Pd/Au metallization 29, and AuBe/Ti/Au contact 32.
The wafers are cleaved into bars with the appropriate geometry for the desired laser devices. The bars are prepared for vacuum cleaving by scribing cleaving marks at the edges where the mirror facets are to be formed. While the technique provides advantages in cleaving one or both facets we found that the best results were obtained when both laser facets were formed according to the inventive process.
The basic element of the cleaving tool and its principle of operation is described in connection with FIG. 3. Here laser bar 35 is shown mounted with appropriate mounting means 36, which conveniently is a support member for multiple bars and has a design that allows easy insertion into a standard vacuum apparatus. The cleaving tool 37 is a cantilever strip of bimetallic metals. The head 38 of the tool 37 is positioned to bear against the laser bar to cleave the bar at the cleave mark 39. When initially mounted for cleaving the head 38 of the tool 37 may be spaced slightly from the laser bar 35 to allow for mounting the bar in the laser bar fixture. The cleave mark is formed at the edge prior to loading the laser bar in the vacuum apparatus. With the laser bar and cleaving tool in place in the vacuum apparatus (not shown) the cleaving tool is heated in the apparatus to cause the head 38 to come into contact with the laser bar at the appropriate position and apply sufficient force to cleave the laser bar at the cleave mark. The deflected position of the tool is shown in phantom and the cleaved portion of the laser bar is also shown in phantom.
Heating of the cleaving tool can be accomplished in a number of ways. An infra-red heating lamp, or a laser can be directed through a window in the vacuum chamber. Alternatively, a heating filament, shown at 34 in FIG. 3, is activated by an electrical switch external of the vacuum apparatus (not shown).
As is well known, a bimetallic strip is a strip of at least two metals with coefficients of thermal expansion that differ sufficiently to cause the strip to bend upon undergoing a temperature change. The amount of thermal deflection D T in inches at the end of a bimetallic cantilever beam depends on the length L in inches of free length, thickness t in inches of the beam, the flexivity value F L per degree C. of the beam material, and the temperature change ΔT in degrees C., and are related by the formula:
D.sub.T =0.53 F.sub.L ΔTL.sup.2 / t
The thermal force W in ounces generated upon deflection is dependent, in addition to those factors above, on the modulus M of the material in lbs per in 2 , and the volume of material which is affected by the width w of the cantilever bar as well as t and L. These factors are related as follows:
W=2.12 M F.sub.L Δ Twt.sup.2 / L
The thermal force sufficient to cleave a typical laser bar is of the order of 1-3 ounces depending on the thickness and length of the bar and the size of the cleave mark. Other than to generate the required cleaving force the material of the bimetallic strip is not critical to the invention. It should be stable in the conditions in the vacuum apparatus both during cleaving and deposition of the initial passivation layer on the cleaved facets. Also the amount of deflection the cleaving tool is required to undergo is not critical and depends largely on the space between the tool head and the laser bar. If the tool head is virtually in contact with the laser bar the required excursion of the tool head is minimal.
Bi-metallic strips are well known in the art and a number of appropriate materials and strip configurations can be devised by those skilled in the art. An example appears in the following Table.
TABLE 1______________________________________ strip 1 strip 2______________________________________dimensions t = 0.25 mm t = 0.25 mm w = 1.0 mm w = 1.0 mm l = 12.5 mm l = 12.5 mmcomposition 72% Mn 66% Fe 18% Cu 34% Ni 10% Ni______________________________________
This bimetallic strip, mounted in a cantilever mode as shown in FIG. 3, will deflect approximately 0.4 mm upon heating to 50°C. The length of the head portion 34 is 1.5 mm, and the width is 0.5 mm. The head is designed to provide a convenient space between the cleaving tool and the sample being cleaved but does not materially affect the deflection properties of the cleaving tool. The force of this strip that is generated during deflection is approximately 3 ounces, easily sufficient to fracture a laser bar 50-250 microns in width, and 0.3 to 3.0 microns in thickness.
In commercial practice a plurality of cleaving tools would be used to cleave simultaneously a large number of laser bars. A suitable fixture for processing a batch of laser bars is shown in FIG. 4. This fixture and tooling is designed to cleave both ends of the laser bar at once and shows a plurality of laser bars 41 mounted on bar holder 42. The cleaving tools are designated 43 on the low reflectivity (LR) side and 44 on the high reflectivity (HR) side. The cleave marks are indicated at 45.
It is preferred that the fixtures and the vacuum apparatus be designed so that several fixtures can be loaded at a time into the vacuum apparatus. It may also be designed with a load lock separating the cleaving fixture site from the passivating coating location so that fixtures can be loaded and unloaded without breaking the vacuum in the deposition and buffer chambers. This allows continuous manufacture of passivated facets.
The tool shown in FIG. 4 uses a thermostatic strip in a cantilever mode. An alternative arrangement designed to cleave a plurality of laser bars using a bimetallic strip in a different mode is shown schematically in FIG. 5. The cleaving tool in this embodiment has a single head actuated by a single bi-metallic strip to simultaneously cleave a plurality of laser bars. In FIG. 5 the cleaving tool 52 is shown slidably mounted on rails 53 in tool support 51. The laser bars are shown in end view at 54. The single bi-metallic strip is shown at 55. The bimetallic strip in this embodiment operates in a so-called simple mode. In this mode the thermal force factor is approximately four times the force factor for strips operating in the cantilever mode which effectively increases the efficiency of the applied force.
FIG. 5 demonstrates that a variety of configurations can be devised by those skilled in the art to implement the thermostatic cleaving process of the invention. Bi-metallic strips operate in several modes in addition to those described here. For example, thermostatic springs, e.g. coils, could be substituted for the simple thermostatic beam 55 in FIG. 5. Modifications of this kind are considered within the definition, for purposes of the invention, of thermostatic elements, or of the process of thermostatic activation of the cleaving tool.
After cleaving as above described the freshly cleaved mirror facets are passivated without exposure to air. The cleaved facets are transferred through a load lock to a deposition chamber, where a coating is applied. Alternatively the facets can be coated in the same chamber with the deposition source activated either during or immediately following cleaving.
The passivation layer should be nonabsorbing and should not react with the mirror facets. It must act as an effective barrier for diffusion of impurities from the oxide dielectric films that are capable of reacting with mirror facets. The passivation film should be deposited in an oxygen free environment. Materials suitable for passivation layers are Si, Ge, and ZnSe. Our preferred passivation material is ZnSe which meets all the requirements of a passivating film and has several advantages over other materials. It has a wide band gap of 2.75 eV and a nominal refractive index of 2.5 at 830 nm wavelength. ZnSe evaporates stoichiometrically at about 700° C. from an effusion cell. Evaporation at such a low temperature is highly desirable to minimize outgassing due to radiation heating from the chamber walls and other hardware in the evaporation system. The stoichiometric ZnSe has a lattice constant close to that of GaAs with a lattice mismatch of only 0.27% . The optimum sample temperature for epitaxial deposition of ZnSe on GaAs is only 300° C., and thus the thin film of ZnSe on laser facets (which is not heated during deposition ) should be of relatively higher quality than those of materials like Si. ZnSe may also serve the purpose of a non-absorbing mirror. Appropriate thickness for the ZnSe layer is in the range of 30-100 A, and preferably approximately 50 A.
Immediately after deposition of the passivation film, SiO film for LR and HR coatings are deposited. For LR coating, SiO dielectric films with thickness <λ/4 to obtain a 2-5% reflectivity are suitable. Although SiO/ZnSe quarter wave stacks were found to be sufficient for HR coating, we prefer to use Si in place of ZnSe for the high refractive index layer in order to be compatible, as much as possible, with the usual commercial practice. As would occur to those skilled in the art, other materials may be used for the LR and HR coating, e.g. A1 2 0 3 , Si 3 N 4 , and yttrium stabilized zirconia (YSZ).
Various additional modifications of this invention will occur to those skilled in the art. All deviations from the specific teachings of this specification that basically rely on the principles and their equivalents through which the art has been advanced are properly considered within the scope of the invention as described and claimed.
|
The specification describes techniques for cleaving crystal bodies, e.g. semiconductor laser bars, using thermostatic cleaving tools. Use of such tools allows the cleaving process to occur in an ultra high vacuum chamber without the use of mechanical devices activated from the exterior of the chamber. Cleaving occurs automatically and controllably by locally heating the cleaving tools, thereby deflecting the thermostatic element against the laser bar and causing fracture.
| 8
|
FIELD OF THE INVENTION
[0001] This application relates to the field of heating, ventilation and air condition (HVAC) systems, and more particularly to manifolds for use in HVAC systems.
BACKGROUND
[0002] Traditionally, manifolds have been used in HVAC systems in many different ways. One such way is for the placement of sensors, such as pressure sensors in an HVAC system. A problem exists with known manifolds that have inlets and outlets on opposite sides. The placement of the inlets and outlets on a traditional manifold limit the placement of the manifolds when deployed in an HVAC system. Traditional manifolds also require adequate space for the piping connecting to the inlet and outlet that are opposite one another. Another problem with traditional manifolds that are commonly found in HVAC systems, is the additional pipe required to make connections on two sides of a manifold. This additional piping results in additional cost.
[0003] While traditional manifold systems have been used in HVAC systems, a need exists for a manifold that overcomes the known problems.
SUMMARY
[0004] In accordance with one embodiment of the disclosure, there is provided an approach for a manifold that has input and output ports located on the same side of the manifold.
[0005] The above described approaches and advantages of the present invention, as well as others, will become more readily apparent to those of ordinary skill in the art by reference to the following detailed description and accompanying drawings. While it would be desirable to have a manifold that provides one or more of these or other advantageous features, the teachings disclosed herein extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the above-mentioned advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. In the figures, like reference numerals designate corresponding parts throughout the different views.
[0007] FIG. 1 shows a perspective diagram of a fluid manifold with an associated sensor and bracket according to an example implementation of the invention;
[0008] FIG. 2 shows a cut-away view of the fluid manifold of FIG. 1 as viewed from the above in accordance with an example implementation; and
[0009] FIG. 3 shows a flow diagram of the steps for forming the channels of FIG. 2 in the fluid manifold in accordance with an example implementation.
DESCRIPTION
[0010] With reference to FIG. 1 , a perspective diagram 100 of a fluid manifold 102 with an associated sensor 104 and bracket 106 according to an example implementation of the invention is depicted. The fluid manifold 102 may have multiple knobs, such as 108 . The knobs may be formed from a material that is resistant to the type of fluid passing through the fluid manifold 102 . In the current example, FORTRON™ 1140 L4 Polyphenylene Sulfide (PPS) with 40% glass fiber is employed from TICONA. Each knob, such as knob 108 may have multiple seals 110 , 112 . The seals 110 and 112 may also be formed from material that is resistant to type of fluid passing through the fluid manifold 102 . The knobs may be held in the fluid manifold 102 via a clip 113 .
[0011] The sensor 104 may be a pressure sensor or other type of transducer that transmits data about the fluid flowing through the fluid manifold 102 . An example of the sensor that may be used is SIEMENS QBE3100UD25, QBE3100UD50, and QBE3100UD100. The sensor may have two fluid connectors, such as 114 , 116 . Compression fittings, such as 118 , may be used to connect the sensor 104 to copper pipes 120 and 122 . In the current example, copper pipes 120 and 122 are used, but in other implementations the pipes 120 and 122 may be composed of different materials and may be dependent upon the type of fluid that passes through the pipes 120 and 122 . The pipes on the side of the fluid manifold 104 may also have compression fittings 119 similar to 118 . The compression fittings compress to seal around the pipes 120 and 122 and have threads to screw into the senor 104 and manifold 102 .
[0012] The sensor 104 may attach to the bracket 106 with a pair of bolts and washers, such as bolt 124 and lock washer 126 . Similarly, the fluid manifold 102 may be attached to the bracket 106 with a pair of bolts and washers, such as bolt 128 and washer 130 . The bracket 106 may be affixed to a wall or other support prior to mounting the fluid manifold 102 and sensor 104 . In other implementations, the bracket 106 may be mounted using tire-wraps, screws or other fasteners. In yet other implementations, the bracket may only secure the fluid manifold 102 or the sensor 104 rather than both as shown in FIG. 1 .
[0013] The shape of the knobs may have an elongated portion and ribs to assist in grasping and turning the knobs. The knobs may also have an indicator shape or marking that enables a person to identify the direction that the knob faces. To further aid in use of the fluid manifold, a graphic overlay 132 may be affixed to the fluid manifold 102 . In other implementations, multiple graphics may be affixed or painted onto the fluid manifold 102 . In yet other implementations, the graphics may be formed in the material that the fluid manifold is formed from (i.e. by etching or casting).
[0014] The advantage of the fluid manifold 102 may be seen in FIG. 1 with the pipes 120 and 122 being attached to the same side of the fluid manifold 102 . The routing of the pipes 120 and 122 require less material than if the pipe connections were on opposite sides of the fluid manifold 102 . Furthermore, items only attach on two sides of the fluid manifold 102 allowing the fluid manifold to be placed in areas with limited space.
[0015] Turning to FIG. 2 , a cut-away view of the fluid manifold 102 of FIG. 1 as viewed from above in accordance with an example implementation is shown. A pipe that carries fluid may be connected via a connector with threads to inlet 202 that is defined by the fluid manifold 102 . A first knob may control the flow of fluid through a first knob area 210 into the fluid manifold's channel 216 . The fluid flow is typically under “high” pressure in the fluid manifold's channel 216 . The fluid may pass through the fluid manifold 102 to a sensor outlet 206 that is defined by the fluid manifold 102 . The “high pressure” fluid would dead-end at the pressure sensor 104 inlet 116 of FIG. 1 . A pipe that carries fluid may be connected via a connector with threads to inlet 204 that is defined by the fluid manifold 102 . A second knob may control the flow of fluid through a second knob area 212 into the fluid manifold's channels 218 . The fluid flow in the fluid manifold's channels 218 is typically under “low” pressure. The fluid may pass through the fluid manifold 102 to a sensor outlet 208 that is defined by the fluid manifold 102 . The “low” pressure fluid would dead-end at the pressure sensor 104 inlet 114 of FIG. 1 . All of the inlets and outlets may have threads to receive fittings and connectors, such as compression fitting 118 . A third knob area 214 and associated knob may be used to disconnect or equalize or balance the pressure in the fluid manifold if knob area 212 and 210 have their associated knobs set to a closed position ( 210 off, 214 on, and 212 off).
[0016] In FIG. 3 , a flow diagram 300 of the steps for forming the channels 216 and 218 of FIG. 2 in the fluid manifold in accordance with an example implementation. A block of material, such as aluminum may be formed into the general shape of the body of the fluid manifold 102 of FIG. 2 (step 302 ). The forming may be accomplished by an additive process such as casting or by a subtractive process such as milling. The channels may be formed in the fluid manifold by machining (drilling) the channels (step 304 ). The knob areas ( 210 - 214 of FIG. 2 ) may be machined into the aluminum (Step 306 ). The threads in the inlets and outlets ( 202 - 208 ) may be machined into the fluid manifold (Step 308 ). Depending upon the implementations, the inner surface of the fluid manifold may be anodized (step 310 ) to further protect the fluid manifold from the fluid that passes through it. In other implementations, the fluid manifold may be completely anodized. In other implementations, a bleed screw may be used to release pressure in the fluid manifold 102 .
[0017] The foregoing detailed description of one or more embodiments of the fluid manifold has been presented herein by way of example only and not limitation. It will be recognized that there are advantages to certain individual features and functions described herein that may be obtained without incorporating other features and functions described herein. Moreover, it will be recognized that various alternatives, modifications, variations, or improvements of the above-disclosed embodiments and other features and functions, or alternatives thereof, may be desirably combined into many other different embodiments, systems or applications. Presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the appended claims. Therefore, the spirit and scope of any appended claims should not be limited to the description of the embodiments contained herein.
|
A system and method for a fluid manifold with a sensor inlet and sensor outlet located on the same side of the body of the fluid manifold.
| 8
|
This is a divisional of copending application Ser. No. 07/242,008 filed on Sep. 8, 1988, now U.S. Pat. No. 5,071,804.
FIELD OF THE INVENTION
This invention relates to processes for recovering precious metals from aqueous solutions or for removing toxic heavy metals from contaminated aqueous streams by the use of a novel ion-exchange agent, an aluminum-enriched analogue to the zeolite chabazite, hereinafter "Al-Chab." This invention also relates to the novel ion-exchange agent, Al-Chab, and the preparation thereof.
BACKGROUND OF THE INVENTION
Each year in the United States, 40 million tons of precious metal-bearing waste is generated. Of this, only about 5% is currently processed for recovery of the valuable constituents (Reddy, R. G., `Metal, Mineral Waste Processing and Secondary Recovery,` J. Metals, Apr. 1987, 34-38). Three main secondary sources of precious metals are aqueous solutions such as electroplating waste, solids and sludges such as salts and copper refinery anode slimes and metal scrap such as wire and printed circuit boards (Moore, J. J., Chemical Metallurgy, Butterworths, London, U. K., 1981, p. 267).
A method for silver recovery from secondary solid sources using a sulfuric acid leach was developed by Kunda (`Hydrometallurgical Process for Recovery of Silver from Silver Bearing Materials,` Hydrometallurgy, 1981, 77-97). His method for recovery of metallic silver from the sulfate solution involved precipitation of silver sulfate, dissolution of this silver sulfate and, finally, hydrogen precipitation of metallic silver.
Of the many electrolytic processes that have been commercialized for metal recovery from plating waste solutions, some are claimed to have applicability to precious metals. Examples include the Retec heavy metal recovery system which is based on electrolysis onto a porous metal electrode (Duffey, J. G., `Electrochemical Removal of Heavy Metals from Wastewater,` Products Finishing, Aug. 1983, 72-75) and the Andco heavy metal removal system, which is based on electrochemical precipitation (`Andco Heavy Metal Removal Systems, Actual Performance Results,` Andco Environmental Processes, Inc., not dated). Solvent extraction has also been investigated for recovery of silver from aqueous solutions (Rickelton, W. A. and A. J. Robertson, `The Selective Recovery of Silver by Solvent Extraction with Triisobutylphosphine Sulfide,` Society of Mining Engineers of AIME, Preprint No. 84-357, 1984).
Much of the technology for the recovery of precious metals from solids by smelting is derived from fire assaying techniques (Gold Institute, `The Fire Assay of Gold,` published by the Institute, Jan. 1985). Smelting for metal recovery is limited to materials of high precious metals content (generally greater then 10%) since the matrix containing the metals is destroyed by the process. Smelting would thus be limited to materials such as copper anode slimes and metal alloy scrap. Loaded sorbents or ion-exchange agents could be processed economically by smelting if they were very highly loaded, beyond the range of what is typical for carbonaceous or organic sorbents.
In general, smelting requires fluxes and other slag-forming agents. A reducing agent such as zinc or starch may also be required. The composition of the smelting charge must be determined on a case-by-case basis.
U.S. Pat. No. 4,456,391 (Reimann, `Recovery of Silver from Silver Zeolite,)` discloses a process for recovering high purity silver from a silver exchanged zeolite (of unspecified composition) used to recover iodine from radioactive waste streams. The process involves heating the silver exchanged zeolite with slag forming agents to melt and fluidize the zeolite, releasing the silver. The silver concentrate is re-melted and treated with oxygen and a flux to remove impurities.
The toxicity of certain heavy metals such as lead has been known to man for centuries. In the United States, the Environmental Protection Agency has declared lead and its compounds to be priority environmental pollutants and has begun establishing concentration limits for drinking water(Tackett, S. L., `Lead in the environment: Effects of human exposure,` American Laboratory, Jul. 1987, 32-41).
Lead removal from aqueous streams has largely been based on precipitation by pH adjustment with agents such as CaO. Unfortunately, such methods often result in gelatinous precipitates which are hard to handle, and these methods are usually not effective in solutions containing complex ions. Alternative methods have been proposed including electrodialysis, liquid membrane separation and ion-exchange (Liozidou, M. and R. P. Townsend, `Ion-exchange properties of natural clinoptilolite, ferrierite and mordenite: Part 2. Lead-sodium and lead-ammonium equilibria,` Zeolites, Mar. 1987, 153-159). Application of the natural zeolites mordenite and clinoptilolite to the control of lead pollution has been proposed (Liozidou, M., `Heavy metal removal using natural zeolites,` Proc. 5th Int. Conf. on Heavy Metals in the Environment, Vol. I, 1985, pp 649-651). However, these materials are of relatively low exchange capacity (<2 meq/g) and of unimpressive selectivity, a vital concern in dealing with streams where competing ions predominate.
The aluminum framework enrichment technique employed in the practice of this invention using chabazite may be utilized with other zeolites. Tu, U.S. Pat. No. 4,250,059, describes a technique for preparing a catalytic composite by calcining a zeolite in a mixture with alumina, but does not comment on whether or not the alumina enters the zeolite framework. U.S. Pat. No. 4,683,334 (Bergna, et. al.), relates to modifications of a zeolite which may be chabazite by elements which may be aluminum.
Examples of the use of chabazite in adsorptive or catalytic applications are given by Sherman, et. al. (U.S. Pat. No. 4,663,052), Bergna, et. al. (see above), Coe, et. al. (U.S. Pat. No. 4,732,584) and Abrams, et. al. (U.S. Pat. No. 4,737,592).
THE INVENTION
It would be desirable to identify an adsorbent with a high capacity and extreme selectivity for toxic heavy metals such as lead in its common form (Pb 2+ ). This is accomplished by the present invention.
It would also be desirable to identify a high selectivity, high capacity adsorbent for precious metals from which the metals can be extracted simply and economically in a relatively pure state. This is also accomplished by the present invention.
In accordance with this invention, a novel high capacity, highly selective adsorbent is provided by treating a source of the mineral chabazite with an alkaline solution containing a source of aluminum to introduce additional aluminum into the framework of the chabazite, preferably introducing sufficient aluminum to result in a framework Si:Al molar ratio of about 1:1, thereby maximizing the number of potentially active sites for ion-exchange.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plot of the calcium exchange capacity of the Al-Chab product as a function of the amount of hydrous alumina incorporated into the reaction mixture.
FIG. 2 is a graphical comparison of the X-ray diffraction (XRD) powder patterns of the starting sodium chabazite and the Al-Chab product.
FIG. 3 is a graphical comparison of the XRD powder patterns of the novel Al-Chab product and zeolite K-G1 prepared in-house.
FIG. 4 is a comparative plot of ammonium ion-exchange isotherms for mineral chabazite and the novel product, Al-Chab.
FIG. 5 is a comparative plot of silver ion-exchange isotherms for mineral chabazite and Al-Chab.
FIG. 6 is a comparative plot of equilibrium lead removal from solution by mineral chabazite and Al-Chab.
DESCRIPTION OF PREFERRED EMBODIMENTS
In order to maximize the number of potentially active sites for ion-exchange reactions, the framework aluminum content of a zeolite must be brought to a maximum. This maximum is obtained in an aluminosilicate zeolite when the framework Si:Al ratio approaches 1, as it does in the Al-Chab product. (Normally the Si:Al molar ratio of pure mineral chabazite is about 3.0). A lesser degree of aluminum incorporation may be accomplished by reducing the available aluminum below the amount necessary to equal the molar amount of available silicon during the conversion (see FIG. 1). However, exchangeable framework aluminum sites, as measured by absolute calcium exchange capacity at reflux temperatures, will not increase above their maximum at a 1:1 Si:Al ratio with further addition of soluble aluminum.
In a typical preparation of the ion-exchange agent of the present invention, Al-Chab, 250g (air-equilibrated) of Bowie, Arizona raw mineral chabazite was ground to a nominal particle size of -200 mesh and combined with 1.0 kg D. I. H 2 O, 110 g NaOH and 120 g Hydral® alumina (64.1 wt. % Al 2 O 3 ) in a 1/2 gallon plastic jug. The jug was placed open in a constant temperature bath at 72.5±2° C. and the contents were agitated gently by an overhead stirrer for 72 hours. The contents were rinsed with 3 liters of D. I. water and following drying for 2 hours at approximately 125° C. were characterized by XRD, wet chemical analysis and ion-exchange. Chemical analysis of the recovered (approximately 350 g) material and the starting Bowie, Ariz. mineral chabazite are presented as Table 1. A comparison of the XRD patterns of the starting Bowie mineral chabazite and the Al-Chab product is shown in FIG. 2.
Synthetic zeolite K-GI (Barrer, R. M., J. Chem. Soc. Faraday Trans. 1, 1956, 68), and the newly discovered mineral willhendersonite are claimed to be "high aluminum" types of chabazite and therefore serve as the closest comparative members of the known chabazite-type zeolites to any potentially new aluminum-enriched member. Samples of K-G1 were prepared in-house
TABLE 1______________________________________Chemical Compositions and Ion-Exchange Capacities ofChabazite and Al-Chab(V.F. Basis) Mineral Chabazite Al-Chab Product______________________________________Al.sub.2 O.sub.3 17.1 35.2SiO.sub.2 65.7 41.2Na.sub.2 O 9.0 19.9CaO 1.47 0.2K.sub.2 O 0.45 0.45MgO 3.32 0.5Fe.sub.2 O.sub.3 3.70 1.94LOI (1,000° C.) 20.5 18.3Si:Al 3.26 0.99Na.sup.+ available for 2.90 meq/g 6.42 meq/gion-exchange*______________________________________ *calculated from sodium analyses
using the method of Barrer. Samples of willhendersonite were unavailable.
X-ray powder diffraction patterns serve as a prime tool in differentiating between molecular sieve zeolites. A comparison of the XRD patterns of zeolite K-GI (Breck, D. W., Zeolite Molecular Sieves, R. E. Krieger Publishing Co., Malabar, FL, 1984, p. 358), willhendersonite (Peacor, D. R.: P. J. Dunn, W. B. Simmons, E. Tillmanns and R. X. Fischer, `Willhendersonite, a new zeolite isostructural with chabazite,` American Mineralogist, 1984, 186-189) and the new species Al-Chab is presented in Table 2. The pattern of the Al-Chab was obtained with a Phillips Model 3720 Automated X-ray Diffractometer using Cu-Ka radiation. The willhendersonite and K-G1 patterns were taken from the references. It is evident from the comparison of the patterns that, while willhendersonite resembles mineral chabazite, its powder pattern
TABLE 2______________________________________X-Ray Diffraction Patterns [d-A°, (I/I.sub.o)]*K-G1 Willhendersonite Al-Chab______________________________________9.47 (ms) -- 9.48 ± .05 (40 ± 10)-- 9.16 (100) --6.90 (m) -- ---- -- ---- -- 6.36 ± .04 (15 ± 5)5.22 (m) 5.18 (30)4.32 (s) -- 4.33 ± .03 (30 ± 10)-- 4.09 (40) --3.97 (ms) 3.93 (20) ---- 3.82 (20) --3.70 (w) 3.71 (30) 3.68 ± .02 (45 ± 10)3.46 (w) -- 3.44 ± .02 (10 ± 5)-- -- 3.24 ± .02 (15 ± 5)3.11 (mw) -- ---- -- 3.02 ± .01 (35 ± 10)2.93 (vvs) 2.907 (60) 2.92 ± .01 (100)2.80 (w) 2.804 (50) --2.59 (s) -- 2.60 ± .01 (35 ± 10)-- -- 2.56 ± .01 (25 ± 10)-- 2.538 (20) ---- 2.508 (20) --______________________________________ *0-40° 2-theta, I/I.sub.o > 10% only
is much different from that of Al-Chab. Willhendersonite, for example, does not show the strong Al-Chab peaks at 3.02 and 2.60 Å°. Significant differences are also noted between the patterns for Al-Chab and K-G1. In general, there are large differences in position for all peaks between the lead peaks at about 9.5 Å° and the major peaks at about 2.92Å°.
Some of this difference in XRD patterns could possibly have
TABLE 3______________________________________X-Ray Diffraction Patterns [d-A°, (I/I.sub.o)]*K-G1 (Barrer) Na-K-G1 (in-house) Al-Chab______________________________________9.47 (ms) 9.44 (ms) 9.48 (40)6.90 (m) 6.87 (mw) ---- -- 6.36 (15)5.22 (m) 5.18 (mw) --4.32 (s) 4.33 (mw) 4.33 (30)3.97 (ms) 3.96 (mw) --3.70 (w) 3.68 (vvw) 3.68 (45)3.46 (w) 3.44 (ms) 3.44 (10)-- 3.22 (w) 3.24 (15)3.11 (mw) -- ---- -- 3.02 (35)2.93 (vvs) 2.93 (vvs) 2.92 (100)2.80 (w) 2.79 (w) --2.59 (s) 2.60 (ms) 2.60 (35)-- -- 2.56 (25)______________________________________ *0-40° 2-theta, I/I.sub.o >10% only
been due to differences in the counter the various species. XRD patterns of various cation-exchanged forms of Al-Chab, however, show minor changes in interplanar spacing and peak relative intensity, much smaller than the differences between the three minerals.
To further establish the uniqueness of the invention material, a sodium form of K-G1 was prepared in-house using the method of Barrer. The XRD patterns of the in-house prepared K-G1 and Al-Chab are compared to the pattern given for K-G1 by Barrer in Table 3. It is seen there that the pattern for the K-G1 prepared in-house very closely matches that given by Barrer, and that either K-G1 pattern shows large differences from the Al-Chab pattern as described above.
While some differences in XRD patterns may possibly be related to crystalline morphology, equilibrium ion-exchange properties are not so dependent. Al-Chab has been found to be extremely selective towards heavy metals, especially divalent cations such as Ba 2+ , Sr 2+ , Pb 2+ , Cd 2+ and Hg 2+ , even at trace (ppm) levels. This behavior contrasts to that of the mineral willhendersonite which, despite prolonged exposure to ground water, was found to be free of strontium and barium, but rich in calcium. These chemical analysis results, coupled with the fact that high-calcium members of the chabazite group are inherently difficult to ion-exchange, make it reasonable to presume that willhendersonite, despite its high aluminum content, is an inferior ion-exchange agent.
Ion exchange tests were also used to further differentiate between Al-Chab and K-G1. Barrer has stated that for aluminum-rich (high charge density) K-G1, ion-exchange of heavy metals (high atomic weight) becomes less favored as charge density (aluminum content) increases. Comparative ion-exchange isotherms for ammonium ions (NH 4 + ) on mineral chabazite and Al-Chab are shown in FIG. 4. These show that, contrary to the expected behavior of K-G1, ammonium capacity decreased with aluminum addition. The anomalous behavior was confirmed by ion-exchange tests involving silver (Ag + ) and lead (Pb 2+ ). The capacity of the ion-exchanger for these two heavy metals was greatly increased by aluminum addition. See, for example, the comparative silver isotherm in FIG. 5.
Thus the ion-exchange behavior, taken together with comparative XRD data, set Al-Chab clearly apart from other aluminum-rich members of the chabazite family of zeolites as a novel, potentially valuable ion-exchange agent.
In a typical embodiment of the invention, heavy metals or precious metals are extracted from solution by contact with particles of the ion-exchange agent of the present invention, Al-Chab. This may be accomplished, for example, by stirring the ion exchange agent of the present invention in the metal-bearing solution or by passing the solution through a column of aggregated Al-Chab, or by other suitable means. The precious metal-loaded Al-Chab is then mixed with flux and reductant, if necessary, and loaded into a suitable smelting vessel. The vessel is heated to greater than the melting point of the precious metal (typically 900° to 1200° C.) and maintained at that temperature for sufficient time, typically about one hour. After the smelting period, the precious metals will be found to segregated from the slag.
Precious metal recovery by smelting may involve complex charge formulations. There are several classes of reagent that may be required in a smelting charge. If the material contains base metals such as iron or copper, an oxidant such as litharge (PbO 2 ) or sodium nitrate (NaNO 3 ) will be required. Base metal oxides would be easily separable from the precious metals, which would not be oxidized. If a high volume of base metal oxides is expected during smelting, or if an inorganic sorbent is used, such as Al-Chab, a flux or fluxes may be required so that the impurity oxides can be removed as a liquid. Sodium meta-borate (Na 2 B 4 O 7 ) is a good flux for materials containing aluminum or zinc oxides, such as precious metal-laden Al-Chab. Sodium carbonate (Na 2 CO 3 ) is used as a flux for silica. Lime (calcium oxide, CaO) is used as a sulfur removal agent. Excess silica (SiO 2 ) is sometimes added, as sand, as a bulking agent for the slag.
Processing of precious metal-bearing solids such as jewelry, electronic scrap, salts and sludges can be accomplished by hydrometallurgical means in conjunction with the present invention. Solid wastes containing silver, for example, may be treated with nitric or sulfuric acid to extract silver into a solution, from which the precious metal can easily and economically recovered by the present invention.
Silver can be recovered from aqueous solutions where the metal is present as the cation, i. e. sulfate, nitrate, ammonium or thiourea solutions, easily and economically by the present invention. Gold can likewise be recovered from chloride solutions employing the present invention.
The following examples are provided to illustrate the invention and are not to be taken as limiting the scope of the invention which is defined by the appended claims.
EXAMPLE 1
In an example of the present invention, silver was recovered from a pure silver nitrate solution. The solution was prepared by dissolving 15.75 g of reagent grade silver nitrate (AgNO 3 ) in one liter of deionized water to give a total silver content of 10.00 g and a silver concentration of 10.00 g/l. Twenty-five grams (air-equilibrated) of the ion-exchange agent of this invention, in powdered form, was mixed in the solution for fifteen minutes at room temperature.
Following filtration with deionized water washing, solids were dried at 125° C. for approximately 2 hours. The silver-loaded Al-Chab was then mixed with 25.0 g of sodium borate as flux. The smelting mixture was placed in a suitable-sized open ceramic crucible. Five grams of zinc was placed at the bottom of the crucible to act as a reducing agent.
The open crucible was heated to 2050° F. (1120° C.) at 36° F. (20° C.) per minute and maintained at that temperature for approximately one hour. The melt was cooled and solidified in the crucible. The silver was readily recovered by fracturing the crucible and breaking away the slag. Essentially all of the silver was recovered as a single large bead weighing 9.0 g, and several smaller beads, for a total weight approaching 10.0 g. Further trials, under nearly identical conditions, indicated that the zinc reductant may be unnecessary for silver recovery.
EXAMPLE 2
An additional example of the present invention was performed to evaluate the potential for selective extraction of silver from solutions containing competing base metal ions, using Al-Chab. Specifically, recovery of silver was attempted from nitrate solutions. All solutions used were prepared from reagent grade nitrate salts and deionized water.
Mixed silver/copper nitrate solutions were prepared with 10.0 gpl silver (0.09 M Ag + ) and 2, 15 or 30gpl copper (0.03, 0.24 or 0.47 M Cu 2+ ). These solution compositions correspond approximately to Ag + /Cu 2+ molar ratios of 3:1, 1:3 and 1:5, respectively. A 250 ml portion of each solutions was treated with 25 g of the Al-Chab. Extractions of silver and copper, as measure by standard wet chemical analysis of the solutions, after 15 minutes of agitation at room temperature are given in Table 4.
TABLE 4______________________________________Ratio % extracted from solutionAg.sup.+ to Cu.sup.2+ Ag.sup.+ Cu.sup.2+ Selectivity*______________________________________3:1 44 5.0 5.01:3 37 7.5 21.71:5 28 8.0 22.4______________________________________ ##STR1## -
It is expected that under conditions of more thorough contact, silver recovery would increase significantly. Note that selectivity for silver over copper increases despite increasing copper contamination. The silver that was extracted from solution onto the Al-Chab was easily and nearly quantitatively recovered by the smelting procedure described in Example 1, while essentially all detectable copper remained in the discarded slag as an oxide.
EXAMPLE 3
In an additional test of the present invention, gold was recovered from chloride solutions prepared by dissolving 14 karat gold jewelry in aqua regia and diluting the solution to an appropriate concentration. Upon contact with the Al-Chab, gold was extracted nearly quantitatively from the solution while base-metal alloying additives, such as nickel and zinc, were not extracted.
Gold jewelry (5.66 g, 14 k) was dissolved in approximately 50 g of aqua regia and the resultant solution diluted to 3,000 ml with deionized water. This solution was stirred with 25 g of Al-Chab for 15 minutes at room temperature before filtration and drying of the solids as described in Example 1. The dried Al-Chab was smelted with 25 g of sodium metaborate, under the conditions given in Example 1, yielding gold bead weighing 2.90 g. This bead accounted for nearly 90% of the anticipated amount of recoverable gold, based on the fineness of the jewelry.
EXAMPLE 4
Eleven test solutions comprised of 250 ml of D. I. H 2 O and varying amounts of lead nitrate [Pb(NO 3 ) 2 ], were prepared, mixed with 5 g Al-Chab each, and allowed to stand quiescently at room temperature for 72 hours. The amounts of lead added to the solutions were systematically varied from 0.1 to 10 times the theoretical maximum ion-exchange capacity of the Al-Chab (7 meq/g). Atomic adsorption (AA) analysis of the final solutions revealed lead concentration to be uniformly less than 1 ppm, until a loading of 4 meq/g was exceeded. An identical test employing mineral chabazite which, while quite selective for lead, lacks the capacity and near absolute selectivity of Al-Chab, revealed measurable lead remaining in solution at a loading of less than 1 meq/g. The comparative lead extraction data is represented graphically in FIG. 6.
EXAMPLE 5
The Linde commercial adsorbent, AW500, is a relatively phase-pure, mixed cation mineral chabazite. It was thus predicted that this material should be at least moderately suitable for conversion into Al-Chab. To test this presumption, AW500 was substituted directly for the high sodium chabazite in a standard Al-Chab preparation.
The formulation for this test consisted of 250 g (air-equilibrated) AW500 powder, 120 g of Hydral® hydrated alumina (64.1% Al 2 O 3 ), 110 g NaOH and 1,000 g deionized H 2 O. Agitating this mixture in a water bath at 72.5±2° C. for three days did, in fact, yield Al-Chab. This was evident from a comparison of X-ray diffraction patterns of the product and the original AW500. In particular, the lead peak was shifted to 9.5 Å°, compared to 9.15 Å° for the starting AW500.
|
A novel ion-exchange agent, an aluminum-enriched analogue to the zeolite chabazite, hereinafter "Al-Chab" is disclosed. The Al-Chab is used in processes for recovering precious metals from aqueous solutions or for removing toxic heavy metals from contaminated aqueous streams.
| 8
|
BACKGROUND OF THE INVENTION
A need exists for a simplified, convenient and inexpensive article storage and concealing compartment for the bodies or beds of trucks, such as pickup trucks. While some such devices are known in the prior art, as exemplified by U.S. Pat. No. 4,215,896, the prior art devices tend to be costly, heavy and frequently require the drilling of holes in the truck bed or other structural modifications thereof to accommodate the compartment means.
In contrast to the prior art, the instant invention provides a highly simplified, low cost compartment means for a truck bed which includes an inclined top panel which rises to the level of the top edge of the tailgate of the truck bed and serves the dual purpose of acting as a spoiler to reduce air drag normally caused by the upright tailgate.
Also, according to the invention, the tailgate is utilized as the rear closure of the storage compartment, and the truck bed side walls serve as closures for the opposite sides of the compartment.
In essence, the concealed article storage compartment and spoiler is formed by a single hinged panel attached to a bed plate or panel on which is mounted a pair of opposite side upstanding lock posts which enable locking the inclined hinged panel securely by padlocks or the like in the article concealing and protecting position. No structural modification of the truck bed or body whatsoever is required for the acceptance of the combined device.
Other features and advantages of the invention will become apparent during the course of the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a combined truck bed storage compartment and spoiler according to the invention, the invention being shown separated from the truck bed in phantom lines.
FIG. 2 is a side elevation of the storage compartment and spoiler with the truck bed in cross section.
FIG. 3 is a view similar to FIG. 2 with the device of the invention in a second operative position within the truck bed.
FIG. 4 is a fragmentary exploded perspective view of an adjustable lock post and associated elements of the invention.
FIGS. 5 through 8 are a series of side elevational views depicting variants of the invention.
DETAILED DESCRIPTION
Referring to the drawings in detail wherein like numerals designate like parts, one preferred form of the invention is shown in FIGS. 1-4. In these figures, a pickup truck is illustrated having a truck bed or body including a horizontal floor 10, opposing vertical side walls 11 and a rear tailgate 12 which is vertically swingable on a lower transverse horizontal axis hinge 13. A combined truck bed storage compartment and spoiler 14 forming the subject matter of this invention consists of a flat bed plate or panel 15 which may rest removably on the floor 10 or be fixed thereto permanently, if preferred. The bed plate 15 spans substantially the entire distance between the two side walls 11 and preferably extends for approximately one-half of the length of the floor 10. The rear edge 16 of the bed plate is disposed substantially in registration with the rear edge of the truck bed floor 10.
Hinged to the forward edge of bed plate 15 by a horizontal transverse axis hinge 17 is a swingable top closure panel 18 of the combined storage compartment and spoiler 14. The panel 18 is of the same width as the bed plate 15 and has approximately the same length as the bed plate, whereby the two panels 15 and 18 when positioned in a common horizontal plane, FIG. 3, will cover substantially the entire truck bed floor 10.
Fixed to the rear corners of bed plate 15 is a pair of upstanding rigid lock posts 19, preferably formed in two telescopically adjustable interfitting sections 20 and 21, held in selected adjusted positions by a locking set screw 22, or by equivalent means. Each upper post section 21 carries a top apertured lug 23 engageable through a slot 24 near each rear corner of the top closure panel 18. Padlock shackles 25 can be placed through the apertured lugs 23 above the closure panel 18 to lock the rear end of the closure panel to the tops of posts 19.
In the security closure forming position shown in FIGS. 1 and 2, the panel 18 is inclined at an angle of approximately 30° to the floor 10 and bed plate 15, and rises from the hinge 17 rearwardly so that the rear edge of the panel 18 is in substantial registration with the top edge of the tailgate 12 when the latter is vertically positioned. The tailgate 12 forms the rear closure element of the storage compartment formed by panels 15 and 18 with the two side walls 11. The storage compartment is wedge-shaped and forwardly tapering. The inclined panel 18 serves the second purpose in the invention of an air drag reducer or spoiler as graphically depicted by the airstream arrows in FIG. 2 which are being deflected by the inclined panel or spoiler. Otherwise, the upright tailgate 12 would trap the airstream flowing downwardly from the cab roof of the truck and cause a pronounced drag effect, lessening fuel economy.
When the closure panel 18 is unlocked from the posts 19 and swung forwardly to the horizontal position shown in FIG. 3 where it lies in a common plane with the bed plate or panel 15, a load 26 of material may be transported in the truck bed without necessitating removal of the combined compartment forming means and spoiler.
The device is characterized by extreme simplicity, convenience and versatility of use, and low cost of manufacturing. The elements 15 and 18 can be formed of plywood, plastics or metal. The structure is strong and durable. It is also much simpler than prior art devices typified by the previously-referenced United States patent.
FIG. 5 shows a first variant of the invention, wherein the inclined top closure panel and spoiler 27 can be a curved plate member instead of flat. All other parts and their functions remain as previously described.
A second variant of the invention is shown in FIG. 6, wherein the top closure of the storage compartment is formed by two hinged panel sections 28 and 29 rather than by a single panel. The panel section 29 is substantially shorter than the section 28 and assumes a steeper angle of inclination than the panel section 28 in the compartment forming position. The smaller panel section 29 is connected to a bed plate 30 by hinge 17 and to the panel section 28 by another hinge 31.
FIG. 7 shows another variant which is structurally similar to the arrangement in FIG. 6, except for the fact that the two panel sections 28 and 29 break downwardly relative to the axis of hinge 31 instead of upwardly in the compartment forming positions.
FIG. 8 reveals how the compartment forming and spoiler device of FIGS. 6 or 7 can be folded flat on the floor 10 of the truck bed. The bed plate 30 remains in place on the floor 10. The smaller panel 29 is revolved rearwardly around the hinge 17 to lie flat on the floor 10 behind the bed plate 30 and the larger panel section 28 can then lie flat closely above the elements 29 and 30, resting on hinge 17 and a rest pad 32 fixed to the bed plate 30.
All of the variants of the invention shown in FIGS. 5 to 8 serve substantially the same dual purpose as the combined device in FIGS. 1 through 4.
It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred examples of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims.
|
A hinged inclined panel in cooperation with the tailgate and two side walls of a truck bed form a secure storage compartment within the truck bed which conceals articles therein. The inclined panel acts as a spoiler by reducing air drag normally caused by the upright tailgate. A secure locking means for the hinged panel is provided.
| 1
|
BACKGROUND OF THE INVENTION
This invention relates to an improved process for converting petroleum residuals. More particularly, this invention relates to an improved process for hydrocracking petroleum residuals.
Heretofore, several processes have been proposed for converting or demetalizing petroleum residuals. Such conversions and demetalizations may be accomplished over a relatively broad range of pressures and, generally, such conversions or demetalizations are accomplished at temperatures known to be effective in hydrocracking operations. It is known to effect such conversions or demetalizations in the presence of a solvent capable of donating hydrogen at the conditions employed to effect the conversion or demetalization and molecular hydrogen may or may not be present. The processes which have been proposed, heretofore, are used primarily for the purpose of upgrading the petroleum residuals such that the converted and demetalized product can satisfactorily be used as a feedstock to various petroleum processes such as catalytic cracking, hydrocracking and the like. As a result, however, the processes proposed heretofore have not resulted in significant conversion of the petroleum residual or in significant production of lighter boiling materials, particularly those in the naptha boiling range. The need, then, for an improved process for converting petroleum residuals to lighter products which may be used directly as a fuel is believed readily apparent.
SUMMARY OF THE INVENTION
It has now been discovered that the foregoing and other disadvantages of the prior art processes can be avoided with the method of the present invention and an improved process for converting petroleum residuals provided thereby. It is, therefore, an object of this invention to provide an improved process for the conversion of petroleum residuals. It is another object of this invention to provide such a conversion process wherein the total conversion of residuals is increased. It is still a further object of this invention to provide such an improved process wherein the relative yield of lighter boiling materials is increased. The foregoing and other objects and advantages will become apparent from the description set forth hereinafter and from the drawings appended thereto.
In accordance with the present invention, the foregoing and other objects and advantages are accomplished by converting a petroleum residual in the presence of molecular hydrogen and a hydrogen donor solvent at an elevated pressure and temperature. As pointed out more fully hereinafter, the total conversion of petroleum residual to lower boiling materials is increased by controlling the pressure within a relatively narrow critical range and by effecting the conversion in the presence of a hydrogen donor solvent containing at least 0.8 weight percent donatable hydrogen. As also pointed out more fully hereinafter, continuous operation of the process can be maintained by controlling the concentration of aromatic and hydroaromatic materials in the solvent relative to the amount of paraffinic materials therein.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plot comparing total conversion as a function of holding time for two different solvents;
FIG. 2 is a schematic flow diagram of a process within the scope of the present invention;
FIG. 3 is a plot showing total conversion as a function of pressure for a given solvent;
FIG. 4 is a plot showing the amount of coke produced during operation of the process of this invention as a function of the ratio of paraffinic content to the aromatic and hydroaromatic content of the solvent.
DETAILED DESCRIPTION OF THE INVENTION
As indicated, supra, the present invention relates to an improved process for converting petroleum residuals to lower boiling materials wherein total conversion of the petroleum residual and the yield of lighter boiling materials is increased. As indicated more fully hereinafter, it is critical to the present invention that the liquefaction be accomplished in the presence of a solvent containing at least about 0.8 weight percent donatable hydrogen at the time the solvent is fed to the conversion step; that the ratio of paraffinic materials to aromatic and hydroaromatic materials in the solvent be controlled such that the ratio is within the range from about 0:1 to about 0.5:1; and that the conversion be accomplished in the presence of molecular hydrogen at a partial pressure within the range from about 1500 to about 2500 psia.
In general, the method of the present invention can be used to convert any petroleum residual material. For purposes of this invention, petroleum residual material shall mean the material remaining after a crude oil has been processed to separate lower boiling constitutents. In general, the petroleum residuals will have an initial boiling point within the range from about 650 to about 1050° F. and will be normally solid at atmospheric conditions. The petroleum residuals will, however, be liquid at the conditions used to effect the conversion. The petroleum residuals may be derived or separated from essentially any crude including those generally classed as aromatic, napthenic and paraffinic. In general, the petroleum residuals useful in the method of this invention will be bottoms from a vacuum distillation column but the same could be any residual from a carbonaceous material having an initial boiling point within the range hereinbefore noted that is also liquid at the conditions used to effect the conversion.
In the method of the present invention, the petroleum residual will be combined with a solvent or diluent capable of donating hydrogen at the conditions employed to effect the conversion and containing at least 0.8 weight percent donatable hydrogen. The solvent may be a pure component but is preferably a mixture of components, some of which are capable of donating hydrogen and some of which are not. In a most preferred embodiment, at least a portion of the solvent will be a distillate fraction separated from the conversion liquid product and, depending on the particular petroleum residual subjected to conversion, this distillate fraction may be separately hydrotreated to produce components therein which are capable of donating hydrogen during conversion. In this regard, it should be noted that when the petroleum residual is highly aromatic, the distillate fraction will, generally, contain sufficient aromatic materials, that can be converted via hydrotreating to corresponding hydroaromatic materials to provide all of the donatable hydrogen required in the solvent. When the petroleum residuals are primarily napthenic or paraffinic, however, it will, generally, be necessary to add aromatic and/or hydroaromatic materials to the distillate fraction which has been separated from the conversion product for use as a solvent. Also, it may be necessary, particularly with paraffinic crudes, to remove at least a portion of the paraffinic material in the solvent fraction. When aromatics are added, separate hydrotreating will be necessary to convert at least a portion of the aromatics to corresponding hydroaromatics. When hydroaromatics are added directly, however, such separate hydrotreating will not be necessary. In this regard, it should be noted that an important feature of the present invention is the discovery that paraffins are the principal contributor to coke formation during conversion and that the presence of aromatics and hydroaromatics during such conversions either inhibit the formation of coke or solubilize the same to avoid plugging during conversion operations. Also, in a most preferred embodiment, use of a solvent having characteristics similar to the characteristics of the conversion product increases total conversion of the petroleum residuals. The use of a solvent which is a distillate fraction containing a relatively broad range of compounds is, therefore, particularly advantageous and when the petroleum residual is an aromatic, the solvent should contain aromatic materials, when the petroleum residual is napthenic, the solvent should contain napthenic materials and when the residual is paraffinic, the solvent should contain paraffins.
Compounds which will donate hydrogen during liquefaction are believed well-known in the prior art and many are described in U.S. Pat. No. 3,867,275. These include the indanes, the dihydronapthalenes, the C 10 -C 12 tetrahydronapthalenes, the hexahydroflourines, the dihydro-, tetrahydro-, hexahydro- and octahydrophenanthrenes, the C 12 -C 13 acid napthenes, the tetrohydro-, hexahydro-, and decahydropyrenes, the di-, tetra-, and octahydroanthracenes, and other derivatives of partially saturated aromatic compounds. Particularly effective mixed solvents for use in the present invention include mixtures comprising a distillate fraction separated from the conversion product which is separately hydrotreated to convert at least a portion of the aromatic materials contained therein to the corresponding hydroaromatic components, hydrogenated creosote oils and hydrogenated catalytic cracking cycle stock and mixtures of such mixtures. Particularly effective solvents include distillate fractions of such mixtures having an initial boiling point within the range from about 400° to about 650° F. and a final boiling point within the range from about 850° to about 1050° F. which have been hydrogenated so as to contain at least 25 weight percent of hydrogen donor species and preferably at least 50 weight percent of such species.
In general, the petroleum residual and the solvent will be combined in a solvent-to-residual weight ratio within the range from about 0.5:1 to about 2:1. The combination may be effected in accordance with any procedure obvious to one of ordinary skill in the art which will be effective in uniformly distributing the petroleum residual throughout the solvent. Best results are generally, however, obtained at elevated temperatures within the range from about 100° to about 350° F. in suitable mixing equipment.
After the mixture of petroleum residual and solvent is prepared, the same is then subjected to conversion at a temperature within the range from about 800° to about 850° F. in the presence of molecular hydrogen. Generally, molecular hydrogen will be present at a concentration within the range from about 4 to about 8 weight percent based on petroleum residual and the partial pressure of molecular hydrogen will be within the range from about 1500 to about 2500. The mixture will be held at these conditions for nominal holding time within the range from about 30 to about 120 minutes.
Another important feature of the present invention is the discovery that when a properly selected solvent is used the nominal holding time in either a batch or continuous operation can be extended when the hydrogen partial pressure is maintained within the critical range heretofore noted without a reduction in total conversion of the petroleum residual which has been experienced in processes heretofore proposed. In this regard, it should be noted that total conversion as used herein means the percentage of the petroleum residual which is converted to materials having boiling points less than the initial boiling point of the petroleum residual subjected to conversion. This discovery is illustrated in FIG. 1. Referring then to FIG. 1, curve 1 is a plot of conversion vs. contacting time when a heavy Arab resid was treated in the presence of a non-donor solvent at 840° F. at a solvent-to-residual ratio of 1.5:1 and at a hydrogen partial pressure of 2000 psia. Curve 2 is a plot of conversion vs. holding time at the same conditions except that a solvent capable of donating hydrogen during conversion was employed. In the runs used to generate curve 2, hydrogenated creosote oil was used as a solvent at a solvent-to-residual ratio of 1.5:1. As will be apparent from FIG. 1, significantly increased conversions can be achieved when operating in accordance with the method of the present invention.
While the inventors do not wish to be bound by any particular theory, it is believed that when the hydrogen partial pressure is increased during conversion of a petroleum residual to a value within the critical range heretofore specified in the presence of a solvent capable of donating hydrogen at the conditions of the conversion, free radicals which have formed at the more severe conditions associated with increased holding time in processes proposed heretofore are scavenged by reaction with hydrogen contributed either by the donor solvent or from the molecular hydrogen. Surprisingly, however, a reduction in total conversion has been experienced when the hydrogen partial pressure is increased above about 2500 psia.
While also not wishing to be bound by any particular theory, it is believed that the solvent must contain a sufficient amount of donatable hydrogen to provide at least 0.4 weight percent of such hydrogen based on petroleum resid in the initial mixture of petroleum resid and solvent. It is also believed necessary that the solvent contain at least 50 weight percent aromatic plus hydroaromatic components to prevent plugging as the result of coke formation during conversion.
During the conversion, at least a portion of the petroleum residual will be converted to a normally gaseous product and at least a portion will be converted to a normally liquid product. Generally, the liquid product will have an initial boiling point at or near the atmospheric temperature and a final boiling point equal to the initial boiling point of the petroleum residual and within the range from about 650° to about 1050° F. The liquid product may then be fractionated into any desired fractions for further upgrading or direct use as an end product. Unconverted material; i.e., material having a boiling point equal to or greater than the initial boiling point of the petroleum residual subjected to conversion may either be recycled to the conversion step, burned directly as a fuel or discarded.
In general, at least a portion of the liquid product will be separated and recycled to provide at least a portion of the solvent required to effect the conversion. When the separated fraction contains sufficient aromatics and/or hydroaromatics, it will not be necessary to combine this fraction with any extraneous solvent fractions. To the extent that the separated fraction contains primarily aromatics, this fraction may be subjected to hydrotreating to convert at least a portion of the aromatics to a corresponding hydroaromatic material. When this fraction does not, however, contain sufficient aromatic or hydroaromatic materials, it will be necessary to combine the same with an extraneous solvent fraction to produce a solvent having an aromatic/hydroaromatic concentration within the ranges heretofore specified. A catalytic cracking recycle oil is a particularly preferred extraneous fraction to employ since this oil is particularly high in aromatic materials. Creosote oils may also be used as an extraneous solvent fraction since these oils, too, generally, contain significant concentrations of aromatic materials.
PREFERRED EMBODIMENT
In a preferred embodiment of the present invention, the petroleum residual will be converted at a temperature within the range from about 820° to about 845° F. in the presence of a solvent capable of donating at least about 1.0 weight percent hydrogen, based on petroleum resid in the initial mixture of petroleum resid and solvent, and in the presence of molecular hydrogen at a hydrogen partial pressure within the range from about 1700 to about 2200 psia. In the preferred embodiment, the petroleum residual will be maintained at these conditions for a nominal holding time within the range from about 60 to about 90 minutes. Also in the preferred embodiment, the solvent will contain at least 60 weight percent aromatic and hydroaromatic components and the ratio of paraffinic materials to aromatic and hydroaromatic materials will be within the range from about 0:1 to about 0.25. In a preferred embodiment, the aromatic and hydroaromatic materials may be contained in a distillate fraction of the conversion liquid product or obtained by hydrotreating such a fraction containing aromatic materials or the same may be obtained from alternate sources such as a catalytic cracking cycle oil or a creosote oil. In a most preferred embodiment, however, a petroleum residual containing sufficient aromatic materials will be subjected to liquefaction and a sufficient concentration of aromatic materials will be present in a distillate fraction separated from the conversion liquid product and the required hydroaromatic concentration will be provided by hydrotreating this fraction to convert at least a portion of the aromatic materials to corresponding hydroaromatic materials. Any suitable catalyst may be used during the hydrotreating.
It is believed that the invention will be even better understood by reference to attached FIG. 2 which illustrates a particularly preferred embodiment. Referring then to FIG. 2, a petroleum resid, a suitable solvent and molecular hydrogen are fed into mixing manifold 201 through lines 202, 203 and 204, respectively. The petroleum resid will be introduced at a temperature above the temperature at which the same is liquid and pumpable, generally at a temperature within the range from about 100° to about 350° F. In general, any suitable solvent may be introduced through line 203 to effect "start up" of a commercial operation but at steady state recycle solvent will be introduced through line 205 and only makeup or extraneous solvent will be introduced through line 203. Extraneous solvent will, of course, be introduced when the recycle solvent introduced through line 205 is deficient in aromatic and/or hydroaromatic content. To the extent that hydroaromatic materials are introduced through line 203, the solvent will, preferably, be a hydrogenated creosote oil or a hydrogenated catalytic cracking cycle stock. In general, the solvent and molecular hydrogen will be preheated to a temperature within the range from about 800° to about 850° F. In general, the solvent will contain sufficient donatable hydrogen to provide at least 0.4 weight percent donatable hydrogen based on petroleum resid in the initial mixture and the combined aromatic/hydroaromatic concentration in the solvent will be at least 50 weight percent. The solvent will be combined with a petroleum resid in a ratio within the range from about 0.5:1 to about 2:1, preferably from about 1:1 to about 1.5:1 and hydrogen will be added at a rate within the range from about 4 to about 8 weight percent based on petroleum residual in the initial mixture.
After mixing in mixing manifold 201, the petroleum resid, solvent and molecular hydrogen mixture is fed to conversion reactor 206. In the conversion reactor, the mixture is heated to a temperature within the range from about 800° to about 850° F. at a hydrogen partial pressure within the range from about 1500 to about 2500 psia and at a total pressure within the range from about 1800 to about 2800 psia. The nominal holding time in conversion reactor 206 will range from about 30 to about 120 minutes. In the conversion reactor, at least a portion of the petroleum resid will be converted to a normally gaseous product and at least a portion will be converted to a normally liquid product. Generally, at least a portion of the petroleum resid will remain unconverted.
In the embodiment illustrated, the entire conversion product is withdrawn through line 207 and passed to a first separator 208. In the first separator, a product containing the normally gaseous product and all of the liquid product which is to be recycled as solvent is separated overhead through line 209 and a bottoms product is separated through line 210.
In those embodiments where the recycle solvent will contain aromatics, the fraction withdrawn overhead through line 209 is passed to hydrotreater 211. In the hydrotreater, at least a portion of the aromatic materials are converted to corresponding hydroaromatic materials. Such conversion is believed to be well known in the prior art. Normally, such hydrotreatment will be accomplished at a temperature within the range from about 600° F. to about 950° F., preferably at a temperature within the range from about 650° F. to about 800° F. and at a pressure within the range from about 650 to about 2000 psia, preferably 1000 to about 1500 psia. The hydrogen treat rate during such hydrotreating generally will be within the range from about 1000 to about 10,000 scf/bbl. Any of the known hydrogenation catalyst may be employed, but a "nickel moly" catalyst is most preferred.
In the embodiment illustrated, then, the hydrotreated fraction is withdrawn through line 212 and recombined with the bottoms fraction from separator 208 in line 213. The recombined fractions are then passed to a second separator 214.
In the second separator 214, products boiling below the initial boiling point of the solvent fraction, including normally gaseous materials, are separated overhead through line 215, a fraction, at least a portion of which is intended for use as recycle solvent, is withdrawn through line 216, a fraction having an initial boiling point equal to the higher boiling point of the solvent fraction is withdrawn through line 217 and a bottoms product generally having an initial boiling point equal to the initial boiling point of the petroleum resid subjected to conversion is withdrawn through line 218. In general, the fraction intended to be recycled as solvent will have an initial boiling point within the range from about 400° to about 650° F. and preferably an initial boiling point within the range from about 500° to about 650° F. and, generally, a final boiling point within the range from about 850° to about 1050° F. and preferably a final boiling point within the range from about 950° to about 1050° F. To the extent that this fraction exceeds the amount of solvent required, a portion thereof may be withdrawn as product through line 219 and the remainder recycled as solvent through line 205.
It will be appreciated that while hydrotreating has been illustrated on a relatively broad boiling range product and between a first and second separator, the hydrotreating could be accomplished after the solvent fraction has been separated from the second separator through line 216. As is well known in the prior art, however, hydrogenation does alter the boiling range of the solvent and further separation after hydrogenation affords better control over the boiling range of the solvent fraction. As a result, operation in the manner illustrated in the Figure is preferred.
The overhead product withdrawn through line 215 may be further separated into a normally gaseous product and a liquid product boiling, generally, in the naptha range. The gas may be scrubbed to remove impurities and used as a pipeline gas or as a process fuel. The naptha fraction may be further upgraded in accordance with well-known procedures to yield a high quality gasoline. The material withdrawn through line 219 boils, generally, within the known fuel oil ranges and may be used as such or further upgraded and used either as a diesel fuel or as a fuel oil. The material withdrawn through line 217 boils, generally, within the vacuum gas oil range and may be used as such or further upgraded or converted to different boiling range materials. The bottoms product withdrawn through line 218 may be at least partially recycled to the conversion reactor, burned for fuel value or discarded.
Having thus broadly described the present invention and a preferred embodiment thereof, it is believed that the same will become more apparent by reference to the following examples. It will be appreciated, however, that the examples are presented solely for purposes of illustration and should not be construed as limiting the invention.
EXAMPLE 1
In this example, four runs were completed in an autoclave using a vacuum resid from a heavy Arab crude oil having an initial boiling point of 1000° F. to determine the effect of hydrogen partial pressure on conversion. In each run, a raw creosote oil was used. The solvent was used at a ratio of 1.5:1 based on petroleum residual in the initial blend. The solvent was, then, capable of donating 2.4 weight percent hydrogen based on petroleum resid in the initial mixture. The solvent contained essentially no paraffinic materials and, therefore, the ratio of paraffins to total aromatics plus hydroaromatics was 0. The hydrogen partial pressure was varied between about 1300 and about 2500 psig. After 90 minutes at 820° F. the total conversion, based on petroleum resid was determined. For convenience, the pressures employed and the total conversions obtained are tabulated below and for purposes of easy comparison, the total conversion as a function of pressure is plotted in FIG. 3 for RCO solvent.
______________________________________ Approximate Total ConversionRun Number Pressure, psig Wt. % on Resid______________________________________1 1300 542 1500 583 2000 684 2500 64______________________________________
EXAMPLE 2
In this example, a series of runs were completed using the same vacuum resid used in Example 1 at a hydrogen partial pressure of 2000 psig at a temperature of 840° F. and at a nominal holding time of 60 minutes. The composition of the solvent was, however, varied in each run to determine the effect of solvent composition on the amount of coke make. At completion of experiment, the amount of coke actually prepared or generated was determined. The critical parameters relating to the composition of each solvent and the amount of coke generated is summarized and plotted in FIG. 4.
EXAMPLE 3
In this example, a heavy Arab vacuum resid was converted in a continuous unit using a hydrogenated creosote oil. The hydrogenated creosote oil contained 1.6 weight percent donatable hydrogen and was used in a solvent to resid ratio of 1.5:1. At this ratio, the solvent was capable of donating 2.4 weight percent hydrogen based on resid. The run was completed at 2000 psig at a space velocity of 0.75 v/hour/v and at a hydrogen treat rate of 4500 scf/bbl. The runs were completed at two different temperatures; viz., 840° and 845° F. The total conversion and product yields are tabulated in the table below.
______________________________________Reactor Temperature °F. 840 845______________________________________Yields, Wt %C.sub.1 -C.sub.3 10 12C.sub.4 -350° F. 23 25350-650° F. 25 29650-1000° F. 19 12CONVERSION OF 77 781000° F..sup.+, WT %______________________________________
As will be apparent from the foregoing, particularly when viewed in light of FIG. 1, relatively high total conversions of a petroleum residual can be achieved when operating in accordance with the method of the present invention. As will also be apparent, the yield of lighter boiling range materials is significantly higher than has been achieved with processes heretofore proposed. The method of the present invention, then, offers an improved process for converting petroleum residuals to in-use products.
|
An improved process for hydrocracking petroleum residuals wherein total conversion and the yield of lower boiling range products are increased. The hydrocracking is accomplished in the presence of a hydrogen donor solvent and molecular hydrogen. The conversion is accomplished at a pressure within the range from about 1500 to about 2500 psig and at a temperature within the range from about 800°to about 850° F. Operation at these conditions is essential to achieving the increased conversion and the increased yield of lower boiling liquid products.
While the present invention has been described and illustrated by reference to particular embodiments thereof, it will be appreciated by those of ordinary skill in the art that the same lends itself to variations not necessarily illustrated herein. For this reason, then, references should be made solely to the appended claims for purposes of determining the true scope of the present invention.
| 2
|
FIELD OF INVENTION
[0001] This invention relates generally to providing investment opportunities to investors and, more specifically, to identifying potential investors as prospective purchasers of precious stones who are willing to accept (and pay for) an imitation stone and have the remainder of their allotted finds be invested at a predetermined rate of return.
BACKGROUND OF THE INVENTION
[0002] It is well-known that businesses and other ventures often seek investors who have the present ability to depart with a certain amount of money, for a given period of time, and in return, receive certain benefits in the future. The magnitude of the future benefit may generally depend on the amount of money invested, the length of time for the investment, and the level and type of risk, or uncertainty, that the investor is willing to accept.
[0003] It is also well-known that individuals who are in the market to purchase a precious stone, e.g., a diamond, ruby, sapphire, emerald, etc., have generally made a decision to spend a sizeable amount of money in purchasing the stone. However, even though most consumers may consider the purchase of precious stones to be a wise investment, there is a large amount of uncertainty associated with actual worth, the liquidity, and the appreciation in value of a precious stone.
[0004] More specifically, the valuation of precious stones, such as, e.g., diamonds, in general, is fairly subjective. As such, consumers rarely, if ever, really know whether they are over-paying for a specific diamond, or whether they are “getting a good deal”. In addition, even when a consumer feels that he/she has paid a fair price in acquiring a specific stone, he/she has no way of really knowing whether, and to what extent, the stone has appreciated over time. Moreover, a re-sale market for such stones is not generally available. For these reasons, it is often difficult for consumers to liquidate their precious stone if they so desire.
[0005] Thus, although prospective purchasers of a precious stone represent a group of individuals who have already decided to depart with, or “invest”, a considerable amount of money, the choice as to the means for investment, e.g., the stone, is generally made as an emotional decision, and not necessarily one that is financially sound vis-à-vis a long-term investment. A need, therefore, exists for a method and system by which individuals willing to invest an amount of money are identified and provided with an overall investment product that is both emotionally satisfying and financially sound.
[0006] The features and advantages of the present invention will become more apparent through the following description. It should be understood, however, that the detailed description and specific examples, while indicating particular embodiments of the invention, are given by way of illustration only and various modifications may naturally be performed without deviating from the spirit of the present invention.
BRIEF DESCRIPTION OF THE DRAWING
[0007] FIG. 1 shows an illustration of communication links and potential interaction established among individuals, entities, equipment, and/or electronic computers that may be used in the practice of an embodiment of the present invention.
DETAILED DESCRIPTION
[0008] To address the above-mentioned issues, an embodiment of the present invention is directed to providing an investment vehicle for the consumer by offering to the consumer an imitation stone, e.g., an imitation diamond, ruby, sapphire, emerald, etc., whereby the consumer will be provided with a specific rate of return on his/her investment.
[0009] Certain features of an embodiment of the present invention may be described with reference to the illustrative example that follows. It is noted that, in the present application, a diamond is used as the means by which a potential investor is identified. However, such use is for illustrative purposes only, and other precious stones, for which imitations, or substitutes, are readily available, may also be used in conjunction with the other features of the invention described herein. In addition, the terms “consumer” and/or “investor” are used to refer, generically, to a purchaser, or buyer, whether the purchase (of the imitation stone) is to be made in person (e.g., at a retail store), over the Internet (or similar media), through mail order, or. otherwise.
[0010] As shown in FIG. 1 , the present invention involves the flow of information among several entities, including some or all of: (1) a seller 10 , who may be a seller of both precious (i.e., actual) stones and imitation stones, wherein the seller functions as the central administrator, or clearinghouse, for the process according to embodiments of the invention; (2) one or more investors, or purchasers, 20 , who wish to spend a specified amount of money to purchase a precious stone; (3) one or more investment entities 30 ; (4) one or more retailers 50 of precious and/or imitation stones; and (5) marking equipment 40 , such as, e.g., an engraving machine, that may be used to individually mark each stone for each respective purchaser 20 .
[0011] In one embodiment, the process according to the present invention is initiated when the seller 10 identifies a consumer 20 who is considering buying a precious stone (such as, e.g., a diamond) for a specified amount of money, e.g., $10,000.00. Having identified a purchaser who has already made the decision to depart with $10,000.00, the seller 10 then offers to the purchaser 20 an imitation diamond of the purchaser's choice that costs, e.g., $500.00. The goal, from the seller's point of view, is to offer to the purchaser 20 an imitation diamond that looks and feels as close to the actual diamond that the purchaser 20 had originally sought, so as to fulfill the purchaser's emotional, or sentimental, criteria and, at the same time, enable the purchaser 20 to invest the remainder of his/her money in an investment vehicle other than a diamond.
[0012] Thus, in the above example, assuming that imitation diamonds do not cost more than $1000.00, the purchaser 20 would potentially have at least $9,000.00 left over (i.e., the “remainder”) that could be invested. With this in mind, the seller 10 then presents the purchaser 20 with one or more investment options for investing the remainder, wherein each option carries a different rate of return depending, e.g., on the amount of money being invested and the period of investment.
[0013] For example, the seller 10 may offer: (1) a 4% rate of return if the purchaser 20 agrees to invest $5,000.00 through the seller 10 for a period of 5 years; (2) a 5% rate of return if the purchaser 20 agrees to invest between $9,000.00 and $9,500.00 through the seller 10 for a period of 5 years; and (3) a 4% rate of return if the purchaser 20 agrees to invest between $9,000.00 and $9,500.00 through the seller 10 for a period of 3 years.
[0014] Thus, in the above example, assuming the purchaser 20 is willing to invest the entirety of the remainder and to maximize his/her rate of return, he/she would agree to buy the imitation diamond that costs $500.00 and invest the remaining $9,500.00 in option (2), with a 5% rate of return. In other words, the purchaser 20 would pay to the seller 10 the sum of $10,000.00 in return for the imitation diamond, plus a certificate that indicates that, if the purchaser 20 leaves his/her $9,500.00 untouched for the period of 5 years, then, at the end of the five years, he/she can redeem the certificate for the face value thereof, which will reflect the predetermined rate of return of 5%.
[0015] Thus, from the consumer's point of view, the “front end” of the method and system of the present invention operates as an annuity, or similar investment product, in order to provide the purchaser 20 with a fixed or predetermined rate of return over an agreed-upon period of time. In the “back end”, the seller 10 must invest the $9,500.00 remainder in such a way that, at the end of the agreed-upon term (e.g., five years in the above example), the actual value of the principal plus interest of the remainder will be higher than the face value of the certificate to be issued to the purchaser 20 . Put another way, the seller 10 must be able to invest the remainder in such a way as to earn a higher rate of return than that which is promised to the purchaser 20 ; the difference will constitute the seller's profit.
[0016] According to an embodiment of the invention, in order to achieve the above-mentioned goal, the seller 10 contracts with an insurance company, brokerage company, investment company, or other similar entity (generally referred to as “investment entity” 30 ) which actually takes and invests the remainder, and is the actual guarantor of the purchaser's rate of return. In this way, the seller 10 may be thought of as a “broker”, whose commission is constituted by the difference between: (1) the rate of return that the investment entity 30 is willing to provide to the seller 10 (i.e., an “ultimate” rate of return) and (2) the rate of return that the seller 10 can negotiate with the purchaser 20 .
[0017] In practice, given that the investment options offered to the purchaser 20 provide higher rates of return for longer periods of investment, the contract between the seller 10 and the purchaser 20 , as well as that between the investment entity 30 and the seller 10 , may include penalty provisions for early redemption. Thus, in the above example, if the purchaser 20 , having chosen option (2), decides to redeem his/her certificate after three years rather than waiting for the agreed-upon five-year period to expire, then the investment entity 30 may charge the seller 10 a penalty (for early withdrawal) which, in turn, may be passed on to the purchaser 20 . The penalty may be calculated on a sliding scale, on a flat-rate basis, or on any other basis generally known in the art.
[0018] In one embodiment, the transactions described above are computerized, and may take place over the Internet. In such an embodiment, FIG. 1 represents an electronic network, in which the reference numbers refer to, e.g., computers used at each node to establish communication among the various individuals, entities, and/or equipment.
[0019] In operation, in a computerized embodiment, the seller 10 creates a web site which includes pictures and descriptions of various pieces of imitation stones, such as, e.g., diamonds in the illustrative example used herein. The purchaser 20 contacts the seller's site through means generally known in the art, e.g., through the purchaser's computer, cellular phone, hand-held device, or other means of communication over a network. Here, as before, the seller 10 also provides one or more investment options to the purchaser 20 .
[0020] Once the purchaser 20 decides on a specific (imitation) diamond, as well as the amount of the remainder that the purchaser 20 is willing to invest, the purchaser provides certain required information to the seller 10 , and enters into an online agreement to purchase the imitation diamond for its stated price, and to pay that price, in addition to the remainder amount, to the seller 10 . The payment may be achieved electronically, or through more traditional means such as, e.g., sending a check to the seller 10 .
[0021] Based on the information collected, which may include the purchaser's contact information, credit card number, etc., and the specific imitation diamond and investment option chosen by the purchaser 20 , the latter is then issued a receipt promising delivery of the diamond, as well as the certificate evidencing investment of the remainder, within a given number of days.
[0022] Once the seller 10 has received the funds, e.g., the $10,000.00 in the above example, the seller's computer 10 then may either download the information gathered from the purchaser 20 in order to provide hardcopies of pertinent information to the investment entity 30 , or it may automatically forward the information electronically to the investment entity's computer 30 . The investment entity 30 will then issue a certificate in the purchaser's name, indicating a rate of return (to be paid to the purchaser 20 ) that has been previously negotiated between the investment entity 30 and the seller 10 . Again, this may be sent to the seller 10 in hard copy, or to the seller's computer (or other reception device) 10 via electronic transmission.
[0023] In one embodiment, once the seller 10 receives the certificate information, the latter is input into the seller's computer (if the certificate information was not received electronically), which then communicates the information to a marking apparatus 40 . The latter may be, e.g., a laser-engraving machine, or other machine capable of affixing identifying indicia onto the imitation diamond. When an engraving machine, e.g., is used, the machine engraves the policy number (for the purchaser's investment) and/or other identifying information onto the diamond. In this way, the purchaser 20 will not be at risk of losing the entirety of his/her investment should the diamond and/or the certificate be lost. The seller 10 then sends the engraved diamond and the certificate to the purchaser 20 .
[0024] In an alternative embodiment, the present invention may include a “point-of-sale” element. Here, one or more retailers 50 may contract with the seller 10 to sell an imitation diamond, along with an investment policy, to a purchaser 20 who may walk into the retailer's store, or otherwise contact the retailer 50 , e.g., through a web site set up by the retailer 50 . In order to clarify the scope of the invention, the term “walk-in purchaser” may be used to refer to purchasers who buy the diamond and investment policy through the retailer 50 , regardless of whether such purchasers actually physically visit the retailer's store, or simply contact the retailer via a website, etc.
[0025] In return for the sale, the retailer 50 may receive a commission (e.g., at a per-sale flat rate, or based on the future value of the annuity, etc.) from the seller 10 . As before, the seller 10 negotiates a rate of return with one or more investment entities 30 , wherein the seller's profit is equal to the ultimate (rate of) return provided by the investment entity 30 to the seller 10 , minus the commission paid by the seller 10 to the retailer 50 and the (rate of) return paid by the seller 10 to the walk-in purchaser 20 .
[0026] As with the embodiments that were discussed previously, the embodiment described immediately above may also be either partially or entirely computerized. Thus, for example, the purchaser 20 may contact the retailer 50 electronically, and the retailer 50 may then transmit the purchaser's information to the seller's computer 10 . Regardless, however, once the sale has been finalized, the retailer 50 may send the purchaser's imitation diamond to the seller 10 who, upon receipt of the funds to be invested on behalf of the purchaser 20 , proceeds as outlined previously.
[0027] It is known, in general, that the rate of return is directly proportional to the amount of investment, such that an investment entity may provide a higher rate of return for larger investments by the seller 10 . Therefore, in embodiments of the invention, the seller 10 may pool the remainder amount, or investment funds, from a plurality of purchasers 20 and invest the resulting total investment amount through the investment entity 30 so as to receive a higher ultimate rate of return from the investment entity 30 . This may be specially applicable where the investment entity 30 sets sequential thresholds for paying progressively higher rates of return.
[0028] While the description above refers to particular embodiments of the present invention, it will be understood that modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.
[0029] The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
|
A method and system for providing an investment opportunity whereby investors are provided a positive return on their investment, while, at the same time, receiving the benefit of an imitation stone that satisfies their required criteria in a precious stone includes identifying a prospective purchaser of a precious stone and, based on the total amount of money that the purchaser is willing to spend, offering an imitation stone for a fraction of the price, and investing the remainder with a predetermined rate of return. The money is invested through an investment entity, with a central administrator facilitating the transactions and receiving a percentage from the investment entity. Various retailers of stones may perform the actual sale to the purchaser in return for a commission from the central administrator. In addition, aspects of the invented method and system may be computerized, including electronic communication among the various entities within a network.
| 6
|
FIELD OF THE INVENTION
The present invention relates to frames, racks or stands, and more specifically to stands used to safely support large and heavy materials, including slabs, frames or trusses containing marble, granite, glass, sheet metal or wood.
BACKGROUND OF THE INVENTION
The handling of large heavy slabs of material, such as marble or granite, can be labor intensive and dangerous. An individual slab of marble may weigh as much as 1,200 pounds. To move an individual slab, the handler attaches a lifting clamp or similar device to the top edge of the slab. The clamp may be connected to a crane, an overhead winch, a fork lift or other lifting means. Once the clamp is attached to the slab, the slab can be lifted from its position and moved to a desired location.
Attachment of the clamp to the top edge of the slab is often difficult. Many times, the slab is leaned up against a wall or object, with the top edge of the slab resting flush against the adjacent wall or object. To place the clamp around the top edge, the slab must be tilted away from the wall or object to create adequate clearance for the clamp.
In many cases, the handlers tilt the slab by hand, insert a spacing block between the slab and the adjacent surface, and then lean the slab back against the spacing block to establish a clearance between the top edge of the slab and the adjacent wall or object. This method requires at least two laborers to complete, due to the weight of the slab. In addition, the method is very cumbersome. Some slabs have a height of over six feet, making it difficult to tilt the slab and place the spacing block behind the slab. Once the spacing block is placed, the block can fall down between the slab and the adjacent wall or object, allowing the top edge to fall back against the wall or object. Moreover, there may be insufficient space for two laborers to work around the slab. For instance, slabs may be delivered on a fully loaded flat bed truck. In such cases, laborers must stand on narrow ledges on the truck bed to maneuver the slabs and prepare them for lifting.
Aside from its difficulties, the method described above is very dangerous. The handler who holds the slab in a tilted position can lose grip on the slab or be overcome by the slab's weight if the slab is tilted too much. The handler who reaches behind the slab to place the spacing block risks crushing a finger or an arm if the slab falls back against the adjacent wall or object. As a result, this method has many problems regarding implementation and worker safety.
SUMMARY OF THE INVENTION
With the foregoing in mind, the present invention provides an apparatus for safely holding a heavy slab. In particular, the present invention holds a slab away from adjacent walls or objects to allow a lifting clamp to be attached to the top edge of the slab. The apparatus includes a light-weight free-standing frame or stand that safely holds a slab in a tilted position to allow a handler to attach a lifting clamp to the slab. Since the stand safely holds the slab, one person can tilt the slab and attach the lifting clamp to the slab without any assistance. The stand is compact so that it can easily be lifted and used in areas where space is limited, such as the edge of a flat bed truck. The present invention also includes a method for safely placing a slab in a tilted position on a stand to allow attachment of a lifting clamp to the slab.
The apparatus preferably includes a base member attached to the midpoint of a cross member, forming a T shape. A front support member extends generally vertically from the midpoint of the cross member. The front support member is braced by a rear support member that extends from the rear end of the base member up to a point along the mid span of the front support member. A toe plate is connected to the front of the cross member and extends forwardly from the apparatus to be inserted beneath a slab. The toe plate and front support member are pitched so as to allow the slab to be leaned against the stand at a small angle. In this position, the slab's force on the stand is significantly small relative to the weight of the slab.
DESCRIPTION OF THE DRAWINGS
All of the objects of the present invention are more fully set forth hereinafter with reference to the accompanying drawings, wherein:
FIG. 1 is an elevation view of the preferred embodiment prepared for use;
FIG. 2 is a frontal view of the device in FIG. 1; and
FIG. 3 is an elevation view of the device in FIG. 1 illustrating the operation of the device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1-3 in general and to FIG. 1 specifically, there is shown a stone stand 10 having a base 20 and a support frame 30 that extends generally vertically from the base to form a rigid stand. The stand 10 is compact and light-weight so that it can be easily lifted and maneuvered. A toe plate 40 extends forwardly from the base 20 and is configured to be inserted beneath a slab of material 5 . Prior to being lifted, the slab 5 is positioned so that the bottom edge of the slab is raised above the floor. In FIG. 1, the slab is raised off the floor using wooden shims 2 .
The stand 10 is compact, which allows the stand to be used in areas where space is limited. For instance, when slabs are off-loaded from flat bed trucks, the slabs take up much of the truck bed, so that workers must stand on narrow ledges to maneuver the slabs. The stone stand 10 is compact enough to be used safely on narrow ledges. The base 20 is formed by two members, which take up very little floor space.
Referring to FIGS. 1-2, the construction of the base 20 is shown. The base 20 is formed by a base member 22 attached to a cross member 24 . Preferably, the base member 22 is attached to an edge of the cross member 24 such that the end of the base member is connected at the midpoint of the cross member. Preferably, the length of the base member 22 is eighteen inches or shorter, so that the stand 10 may be used on narrow ledges or other areas having limited floor space.
Referring again to FIG. 1, the support frame 30 includes an elongated vertical front support member 32 and a rear support member 34 connected to the rear edge of the front support member. The front support member 32 extends generally vertically from the midpoint of the top edge of the cross member 24 . The front support member 32 forms an acute angle 38 relative to a vertical axis extending from the lower end of the front support member, as shown by the dashed line in FIG. 1 . Preferably, the angle 38 is between 5 and 10 degrees.
The rear support member 34 extends upwardly from the base 20 and is connected to the front support member 32 to act as a brace for the front support member. More specifically, the rearward end of rear support member 34 is mitered to rest flush against the top edge of the base member 22 near the rearward end of the base member. The rear support member 34 extends upwardly and forwardly from the rearward end of the base member 22 . The forward end of rear support member 34 is mitered to adjoin the rearward edge of front support member 32 and form a brace joint 36 . The brace joint 36 divides the front support member 32 into an upper span 42 and a lower span 44 .
The toe plate 40 extends from the midpoint of the front edge of the cross member 24 , as illustrated in FIG. 1 . The toe plate 40 is an L-shaped member that includes a bottom plate 46 and a back plate 48 generally perpendicular to the bottom plate. Preferably, the front edge of the front support member 32 is flush with the front edge of cross member 24 to form an even surface for mounting the toe plate 40 . The toe plate 40 is connected to the front support member 32 and cross member 24 to form a continuous bottom edge with the bottom edge of the base 20 . More specifically, the toe plate 40 is mounted so that the bottom edge of the bottom plate 46 is generally flush with the bottom edges of the cross member 24 and base member 22 to provide stability and minimize rocking of the stand 10 . The back plate 48 generally conforms to the small tilt angle 38 of the front support member 32 , such that the bottom plate 46 is pitched slightly upwardly as it extends away from the front support member. This incline assists in urging the slab 5 toward a leaning position on the stand 10 .
Referring now to FIG. 3, the slab 5 is shown leaning against the stand 10 . For clarity, the shims 2 are omitted from FIG. 3 . When the slab 5 is leaned against the stand 10 , the top edge of the slab 5 preferably extends above the front support member 32 . In this way, the top of the front support member 32 does not obstruct the top edge of the slab 5 and interfere with the attachment of the lifting clamp. The front support member 32 is configured to receive the slab 5 in a leaning position with the face of the slab flush against the front support member 32 . The slab leans at an angle conforming with the tilt angle 38 of the front support member. In this position, the slab has a center of gravity 6 located at a vertical distance above the base 20 .
The slab 5 exerts a force against the support frame 30 in response to gravity. The force is generally distributed uniformly along the length of the front support member 32 . The tilt angle 38 of the front support member 32 , which generally defines the angle of the slab 5 when the slab is placed on the stand, is very small, preferably ranging between 5 and 10 degrees. Since the slab 5 leans at a small angle on the stand 10 , substantially all of the slab's weight is distributed downwardly, and only a small fraction of the slab's weight bears against the support frame 30 .
When the slab 5 is leaned against the stand 10 , the force that bears against the front support member 32 creates a moment about the midpoint of cross member 24 . This moment urges the front support member 32 to rotate or bend rearwardly. To counterbalance the slab's force on the front support member 32 , the brace joint 36 is preferably positioned so that the joint is higher than the center of gravity of the slab 5 . Moreover, the axial length of the upper span 42 is preferably less than the axial length of the lower span 44 . This gives the support frame 30 stability and limits deflection of the front support member 32 when the slab 5 is leaned on the stand 10 .
The brace joint 36 is also positioned to provide rigidity in the lower span 44 . When shorter slabs are leaned against the stand 10 , there is a potential for buckling or bending in the lower span 44 . This is especially true if the height of the slab is shorter than the length of the lower span 44 . In such a case, the slab's force on the front support member 32 will be absorbed entirely by the lower span 44 . As the ratio of the lower span's length to the thickness of the front support member 32 increases, the potential for buckling in the lower span increases. Therefore, preferably the brace joint 36 is located near the midpoint of the front support member 32 to limit the length of the lower span 44 . More specifically, preferably, the distance between the brace joint 36 and midpoint of the front support member 32 is substantially smaller than the distance between the brace joint and upper end of the front support member.
The base member 22 , cross member 24 , front support member 32 and rear support member 34 are constructed out of strong light-weight materials, such as corrosion-resistant square steel tubing. Preferably, the ends of the steel tubing contain caps to seal off the interior of the tubing and prevent moisture from entering the tubing. The toe plate 40 is formed of a strong material, such as a three eighth inch steel plate or bracket, capable of supporting a slab without deflection. The aforementioned components can be connected using a variety of conventional joining methods, including welding or bolts.
Referring now to FIG. 3, the operation of the stand 10 will be described. The slab 5 to be lifted is initially tilted on its side and placed on shims, beams or the like so that the bottom edge of the slab is raised above the floor. The stand 10 is then inserted beneath the slab 5 and centered so that the toe plate 40 is generally adjacent to the midpoint of the slab's bottom edge. Where the clearance between the slab 5 and floor is small, the stand 10 may be tilted forward as necessary so that the inclined bottom plate 46 can be inserted beneath the slab. The stand 10 is positioned so that the cross member 24 is generally parallel to the front face orientation of the slab 5 .
Once the toe plate 40 is beneath the slab 5 , the stand 10 is maneuvered under the slab until that the back plate 48 of toe plate 40 abuts the face of the slab, as shown in FIG. 3 . Preferably, the vertical clearance between the bottom plate 46 and the slab is no more than one half inch. However, it is not crucial that the bottom edge of the slab 5 contact the bottom plate 46 , since the shims will continue to support the slab. Once the stand 10 is in place, the slab 5 is slowly tilted in the direction marked A in FIG. 3 . The slab is then leaned on the front support member 32 so that a lifting clamp can be attached to the top edge of the slab. The lifting clamp is then raised vertically to lift the slab.
The terms and expressions which have been employed are used as terms of description and not of limitation. There is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof. It is recognized that various modifications are possible within the scope and spirit of the invention. For instance, the device may include a flat steel toe plate fixed to the underside of the base as opposed to the L shaped toe plate 40 described above. This toe plate would provide a uniform planar surface to support the stand and minimize rocking. Accordingly, the invention incorporates variations that fall within the scope of the following claims.
|
A safety stand for safely holding a heavy slab of material is provided. The stand is configured so that a heavy slab can be safely leaned against it. Once the slab is leaned against the stand, the top edge of the slab is in a position such that a lifting clamp or similar device can be attached to the slab. With the stand in place, one person can safely prepare the slab for lifting.
| 4
|
BACKGROUND OF THE INVENTION
The present invention relates to a tire and wheel servicing arrangement comprising different workshop units for effecting respective relevant operations such as bead breaking, tire changing, inflation and balancing. Such specialized units have been available for many years, and it has been customary to mount them as separate units at convenient places of the workshop, often against a wall and with noticeable mutual spacing, whereby it has also been accepted as a requirement to roll or carry the wheels between the units.
SUMMARY OF THE INVENTION
According to the present invention the said different units are looked upon as parts of one integral `servicing system`, in which they are arranged as cooperating units in an operationally successive manner and mutually disposed such that the wheels can be transferred from one unit to the next with a minimum of effort on the part of the operator.
It is a very common practice that in workshops specialized in tire changing and repair each operator has his own set of the said specialized units, because it would otherwise happen rather frequently that one or more operators would have to wait for a first operator to finish his use of a given unit, e.g. a balancing machine. Admittedly, this may happen rather frequently, but it certainly also happens frequently that such a unit is not in use for a considerable period of time. With the system according to the invention, it will be ensured that all of the units are brought into operation in a systematic manner with a relatively short cycle time, whereby the resulting capacity of a single array of units will be very high compared with the more occasional use of different independent units.
In fact, it is a qualified estimate based on experiments that with the use of the system according to the invention, the workshop may work with one in-line-system for every two complete sets of individual, separate units used according to the conventional practice, when also the operators are specialized in working in front of and behind or in the system, respectively, i.e. dealing for one part with the dismounting and remounting of the wheels relative the cars and for another part with the operation of the very wheel treating system.
Thus, the workshop owner may drastically reduce the expenses connected with the aquisation of machinery, or in other words the owner may be encouraged to steadily keep the machinery up to the highest developed standards.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following the invention is described in more detail with reference to the drawing, in which:
FIG. 1 is a perspective view of a system according to the invention seen from the customer's side,
FIG. 2 is a corresponding view of the system seen from the operator's side, and
FIG. 3 is a more detailed view of one of the units of the system.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The system as shown in FIG. 1 comprises a partition panel 2, behind which there is mounted a series of working units to be described in more detail below. The panel 2 forms a rear wall of a workshop bay for receiving cars for wheel repairs and preferably fitted with a car lift for facilitating removal of the wheels. These are then taken to an infeed conveyor 4, which is only a passive roller table slanting slightly downwardly from its front end. At its rear end the wheels will meet a stop, such that the rear wheel position will be a position of entrance to the working system along the panel 2. At this place there is mounted a roller 6 along the inner side edge of the roller table, and a first working unit 8 has a receiving table 10 located immediately outside this roller. Thus, the wheel can simply be drawn or pushed onto the table 10, aided by the roller 6 providing for a rolling support.
The unit 8 is a bead breaker, serving to press the upper tire bead downwardly from the rim by means of an upper pressing tool while the table 10 is rotating. When it is required to break also the opposite bead, e.g. for a complete tire change, the operator can turn the wheel upside down on the table 10, merely by tilting over the wheel, without actually lifting the entire wheel. Alternatively, of course, the unit 8 could be designed so as to effect a bead breaking even at the lower side of the wheel.
The following unit, designated 12, is a tire changer having a rotary wheel supporting table 14 and an upper tool 16 for heeling the tire bead over the rim edge, as well known in the art. The unit 12 is placed so close to the unit 8 that the wheel can be transferred simply by sliding or tilting-over, again without being carried as a whole.
When the repair or tube or tire change has been effected at the unit 12 the wheel will then be correspondingly easily transferable to the subsequent unit, designated 18, which is an automatically operating inflation unit, as such already known in the art. However, it is here designed as a flow-through unit comprising a roller table bottom 20 (FIG. 2) for easy reception and delivery of the lying wheel. In this instance it is imperative that the wheel be oriented with its inflation valve located at the top side of thereof; i.e. with its outer side turned upwardly.
The following and last operation unit is a balancing machine 22, which has a horizontally oriented rotation shaft 24 with an outer mounting head 26 for receiving the wheel in an upright position thereof and with the deep portion of the wheel rim facing the balancing unit, i.e. with the inflation valve carrying wheel side facing away from the unit 22.
When the wheels in the inflation unit 18 are oriented with their valve side turned upwardly it will not be possible to transfer the wheels to the balancing machine by a mere tilting of the wheels, as these will have to be turned by 180°.
It is a special feature of this invention that such a turning may be effected in an easy manner by means of a simple V-shaped frame structure 28 at the outlet end of the roller table bottom 20, see FIG. 2. The wheel may be pushed over the outlet edge of the table 20, whereby it will tilt over this edge and place itself leaning against the first branch of the V-structure 28 and supported against the opposite branch. Then the operator can easily tilt the wheel over to make it lean against the latter branch, now with the rear wheel side upwardly exposed and ready to be tilted once again.
The same result, however, is achievable in a smoother manner when the V-structure 28, as shown in FIG. 3 and in fact also in FIG. 1, is tiltably connected with the roller table 20 such that in a receiving position the said first branch, designated 30 and equipped with rollers, forms a straight continuation of the roller table 20 for easy reception of the wheel. As the weight of the wheel is transferred to the roller branch 30, the latter will yield against the action of a gas spring (not shown) so as to pivot down to the position shown in dotted lines in FIG. 3 and in full lines in FIG. 2. In continuation of that movement it is easy to tilt the wheel over against the other V-branch, 32, and then further over the end of the V-branch 32 such that the former top end of the wheel is now laid down on a support member 34, onto which the wheel is to be placed preparatory to its being mounted in the balancing machine 22. The operator then tilts the wheel into an upright position on the support 34, which belongs to a unit 36 of known type for supporting the wheel in a `height floating` or `weightless` manner, enabling the wheel to be adjusted both up and down by a very small pressure against it, in order to adjust the center hole of the wheel rim to the correct position for insertion on the mounting head 26 of the balancing machine 22. Moreover, the support unit 36 is easily displaceable along a rail element 38, whereby the operator, holding the wheel upright on the support member 34, may easily displace the wheel and the support unit 36 towards the balancing machine so as to bring the wheel into its mounting position on the mounting head 26.
When the wheel is removed from the V-branch 32 the structure 28 will pivot up to its receiving position, even assisting in the initial delivery tilting of the wheel onto the support 34.
The support member 34 is caused to be lowered as soon as the wheel is bolted to the mounting head 26, and then the balancing work is done, normally with a security hood 40 lowered over the spinning wheel. Thereafter the support member 34 is raised into contact with the wheel, and the wheel is dismounted from the mounting head. The operator, again holding the wheel upright on the support 34, now displaces the support unit and the wheel back along the rail 38, to a return position outside of the security hood 40. In front of this position there is provided a horizontal carrier plate 42 and an opening in the panel 2, such that the operator can simply roll the finished wheel from the support member 34 onto the plate 42 and then ease the wheel sideways to make it abut an end post 44 of the panel opening or a previously delivered wheel leaning thereagainst. Preferably, the panel opening is wide enough to accommodate four wheels.
An operator on the `car side` of the panel 2, having delivered wheels from one or more cars to the feeding conveyor 4, may take the repaired wheels consecutively or groupwise from the panel opening and remount the wheels on the relevant cars.
The `car side` of the panel will also be a `customer side` and it will be appreciated that a customer desiring to follow the work can walk along the front side of the panel without in any way interfering with the repair operator's work, and yet be in face-to-face relation with the operator such that the customer's view at the operations and communication with the operator will be better than in conventional arrangements where the customer may even stand behind the back of the operator.
Another main advantage is that the repair operator will be able to handle the wheel all the way through the repair line without having to carry the entire wheel at any time, all wheel transfers taking place by way of sliding or tilting of the wheel. It could well be possible to automate the transfer functions, but it has been realized that in the manner described there will be no need for additional mechanical assistance. The functions to be performed can be done in an ergonomically optimized way, such that the price of the entire system can be held reasonably low.
It should be mentioned that an ideal manner of arranging the work will be to use one car side operator, one rapair side operator and one balancing operator.
|
A tire and wheel servicing arrangement including a bead breaking station, a tire changing station, a tire inflating station, and a wheel balancing station in which the stations are positioned sequentially in a line and adjacent each other to permit transfer of a wheel-mounted tire from one station to the next by simply pushing or sliding of the tire. The inflating station can include a V-shaped tire receiver for facilitating turning over of the wheel mounted tire. That tire receiver can be tiltable downwardly under the weight of a wheel mounted tire to aid in positioning the wheel mounted tire on the wheel balancing station.
| 1
|
[0001] The present invention relates to a novel process for preparing 2,5-disubstituted 3-alkyl-thiophenes and more particularly to a process for preparing them that comprises an acylation reaction in position 5 of 2-substituted 3-alkylthiophenes.
PRIOR ART
[0002] 2,5-Disubstituted 3-alkylthiophenes, of general formula
and in particular 2,3-dimethyl-5-benzylthiophene of formula
(R 1 ═A═CH 3 , B═CH 2 , R 3 ═H), are useful synthetic intermediates.
[0003] For example, in U.S. Pat. Nos. 6,121,271 and 6,103,708 and in international patent applications WO 99/61435 and WO 99/58522, compound (Ia) is used as an intermediate in the preparation of medicinal products for treating metabolic disorders related to insulin resistance or hyperglycemia.
[0004] Two different processes for preparing compound (Ia) are also described in the above-mentioned documents.
[0005] More particularly, international patent application WO 99/61435 illustrates the synthesis of compound (Ia) according to the sequence given below:
[0006] As may be seen, this synthesis involves the reduction of 3-methylthiophene-2-carboxaldehyde (step a) to give 2,3-dimethylthiophene, its functionalization in position 5 (step b) and, finally, subsequent reduction of the intermediate alcohol (step c) to give the desired compound (Ia).
[0007] However, this process is difficult to apply industrially since it involves the use of n-BuLi, which is a notoriously flammable reagent that requires an inert atmosphere, an anhydrous medium and a low temperature (−78° C.).
[0008] Another non-neglible drawback is represented by the need to use, in the condensation with benzaldehyde (step b), an intermediate 2,3-dimethylthiophene of high purity in order to minimize the possible side reactions and thus to obtain the desired product (Ia) in acceptable overall yields, which in this case would be about 67%, and with a sufficient degree of purity for subsequent direct synthetic use. The starting material for the process, i.e. 3-methylthiophene-2-carboxaldehyde, is, however, commercially available with a relatively poor degree of purity, generally of about 90%, and consequently the impure 2,3-dimethylthiophene obtained by reducing it cannot be used in unpurified form in the subsequent step, but rather is always subjected to purification; in particular, being a an oil, it is purified by chromatography, which is definitely not very method practicable from an industrial point of view.
[0009] Similarly, the final compound (Ia), which is a high-boiling liquid, is difficult to isolate and therefore another possible purification at level, by means of chromatography or distillation, would be relatively problematic on an industrial scale.
[0010] The second process for preparing compound (Ia), described in patents U.S. Pat. No. 6,121,271 and U.S. Pat. No. 6,103,708 and in international patent application WO 99/58522, may be represented according to the following scheme:
[0011] In this case also, the same drawbacks described above may be encountered, i.e. the use of n-BuLi, which is difficult to work with industrially, and the use of two successive chromatographies for the purification of the intermediate 2,3-dimethylthiophene and the final product (Ia), which are both liquids at room temperature.
[0012] We have now found a novel process for preparing 2,5-disubstituted 3-alkylthiophenes, in particular 2,3-dimethyl-5-benzylthiophene, which is significantly advantageous in industrial terms since it does not use reagents that are relatively difficult to work with such as n-BuLi, it does not require anhydrous conditions or inert atmospheres, and it appreciably simplifies the purification stages. This process makes it possible above all to use commercially available technical-grade starting materials directly, and to obtain the final product (I) in yields comparable to those for the known preparations but with high purity, entirely avoiding the use of chromatographic methods or distillation techniques, both on the intermediates and on the final product. The reason for this is that these final products generally have a purity that allows them to be used directly in subsequent processes without further purification.
SUMMARY OF THE INVENTION
[0013] One subject of the present invention is therefore a process for preparing 2,5-disubstituted 3-alkylthiophenes of formula
in which
A represents a CH 3 , R 2 CH 2 , HOCH 2 or R 2 CH(OH)— group, B represents a CHOH or CH 2 group, R 1 represents H or a C 1 -C 5 alkyl group, R 2 represents a C 1 -C 5 alkyl group, R 3 represents H or a C 1 -C 5 alkyl group or a C 1 -C 5 haloalkyl group, preferably CF 3 , or a halogen chosen from fluorine, chlorine and bromine,
which comprises: (a) the reaction of a compound of formula
in which
A represents a CHO, CH 3 , R 2 CH 2 or R 2 —CO— group, and R 1 and R 2 have the meanings given above; with a compound of formula
in which
X represents OH, halogen or a group of formula
or a group of formula
—OCOOR 4 (VI)
in which
R 4 represents a C 1 -C 5 alkyl, an optionally substituted benzyl or an optionally substituted aryl, and R 3 has the meanings given above; to give a compound of formula
in which
A, R 1 , R 2 and R 3 have the meanings given above; and
(b) the reduction of the compound of formula (IV) thus obtained to give the compound of formula (I).
DESCRIPTION OF THE INVENTION
[0031] The process that is the subject of the present invention comprises the acylation reaction (a) of the compound of formula II and the subsequent reduction (b) of the acyl intermediate of formula IV to give the desired compound I.
[0032] Generally, the starting compound of formula II is commercially available or may be prepared according to processes known to those skilled in the art. For example, in the case where it is desired to use the preferred compound IIb (R 1 ═A═CH 3 ) as starting compound, it may be prepared, in accordance with that described in the abovementioned prior art, by reduction, with hydrazine and potassium hydroxide, of the commercially available compound IIa (R 1 ═CH 3 , A═CHO). As disclosed previously, an appreciable advantage of the present process is the direct use of the commercial compound IIa (purity of about 90%) in the reduction reaction to give IIb or, alternatively, in the acylation reaction (a) to give compound IVa (R 1 ═CH 3 , A═CHO, R 3 ═H).
[0033] The acylation reaction referred to in point (a) is generally performed under the standard conditions of Friedel-Crafts acylations.
[0034] The acylating compound of formula III may be a carboxylic acid (X═OH), an acid halide (X=halogen), preferably chloride (X═Cl), a symmetrical anhydride (X═V) or a mixed anhydride (X═VI).
[0035] Preferred mixed anhydrides are those in which R 4 represents methyl, ethyl, i-butyl or benzyl, more preferably methyl or ethyl.
[0036] Acyl halides are preferred acylating agents, and benzoyl chloride is even more preferred (IIIa, X═Cl, R 3 ═H).
[0037] The catalysts that may be used in this reaction are generally Lewis acids, for instance AlCl 3 , SbF 5 , FeCl 3 , TiCl 4 or BF 3 , preferably AlCl 3 .
[0038] Suitable solvents are those commonly used by those skilled in the art for reactions of this type, i.e. chlorinated solvents such as methylene chloride, chloroform or trichloroethane, or deactivated aromatic solvents such as nitrobenzene, preferably methylene chloride.
[0039] In the acylation reaction (a), a molar ratio of compound III/Lewis acid/compound II generally of between 0.9-1.5/0.9-1.5/1 and preferably of about 1/1/1 per unit of compound II is used.
[0040] The second step of the present process (step b) involves the reduction of the intermediate of formula IV to give the desired product of formula I.
[0041] Depending on the structure of the intermediate IV and of the final compound I, this reduction may be performed by means of a single reductive treatment (b) or, preferably, by means of a first reduction reaction (b 1 ), optionally followed by a second reduction reaction (b 2 ).
[0042] In the case where it is desired to obtain the completely reduced compounds of formula I directly, a single reductive treatment of the compound of formula IV will be performed to give the compound of formula I in which A═CH 3 or R 2 CH 2 and B═CH 2 .
[0043] In this case, a reduction reaction may be performed under the standard conditions for reducing C═O groups to CH 2 groups, for example by using a borohydride in the presence of a strong acid, for instance trifluoroacetic acid, methanesulphonic acid or sulphuric acid, preferably sodium borohydride or sodium cyanoborohydride in the presence of trifluoroacetic acid, or zinc iodide or trimethylsilyl chloride or trialkylsilanes in the presence of trifluoroacetic acid.
[0044] Alternatively, the process may be performed by means of a first reduction reaction (b 1 ) of the compound of formula
in which A represents a CHO, CH 3 , R 2 CH 2 or R 2 —CO— group, to give the hydroxylated intermediate compound of formula
in which A represents a CH 3 , R 2 CH 2 , HOCH 2 or R 2 CH(OH)— group and B═CHOH, optionally followed by a second reduction reaction (b 2 ) of the hydroxylated intermediate of formula I as defined above, to give the final compound of formula
in which A represents a CH 3 or R 2 CH 2 group and B═CH 2 .
[0045] In the first step (b 1 ), suitable conditions may be used to perform the reduction of the C═O groups to CHOH groups, for instance treatment with metal hydrides such as sodium borohydride, lithium aluminium hydride or boranes, preferably with sodium borohydride in alkaline medium, or alternatively by treatment with aluminium isopropoxide (Meerwein-Ponndorf-Verley reaction).
[0046] The intermediate hydroxylated derivatives of formula I as defined above, preferably the compounds Ib (R 1 ═CH 3 , A═CH 2 OH, B═CHOH, R 3 ═H) or Ic (R 1 ═A═CH 3 , B═CHOH, R 3 ═H) may then be subjected to the subsequent reduction step (b 2 ), directly or, preferably, after purification.
[0047] This purification is advantageously performed by crystallization, since the said hydroxylated intermediates are generally crystalline solids.
[0048] Suitable crystallization solvents are usually apolar solvents such as ethers, for example diethyl ether, diisopropyl ether or methyl tert-butyl ether, aromatic hydrocarbons, for example toluene or xylene, aliphatic hydrocarbons, for example hexane, heptane or cyclohexane, or mixtures of these solvents.
[0049] By then performing this preferred variant of the process, which involves a first reduction (CO->CHOH, b 1 ), the crystallization of the hydroxylated intermediate and its subsequent total reduction (CHOH->CH 2 b 2 ), it is thus possible to perform the entire synthetic sequence of the present invention without the need for chromatographic purifications or distillations, which are drawbacks from an industrial point of view.
[0050] The hydroxylated compounds of formula I, preferably the abovementioned compounds Ib and Ic, which are preferably purified, may then be converted into the corresponding completely reduced compounds of formula I, preferably into compound Ia, by reduction (b 2 ) of the CHOH groups to CH 2 groups, for example by treatment with a borohydride in the presence of a strong acid, for instance trifluoroacetic acid, methanesulphonic acid or sulphuric acid, preferably with sodium borohydride or sodium cyanoborohydride and trifluoroacetic acid, or zinc iodide, or, surprisingly, by means of catalytic hydrogenation.
[0051] This latter reaction may be performed simply by treating the hydroxylated compound I, dissolved in a suitable solvent such as an alcohol, for instance methanol, ethanol or isopropanol, preferably methanol, or in mixtures of water and alcohols at a hydrogen pressure of between about 1 and 10 bar, at a temperature of between about 15 and 60° C., in the presence of a hydrogenation catalyst chosen from palladium and platinum, preferably palladium supported on an inert support such as carbon, alumina, silica or zeolites, preferably on carbon, in a neutral or acidic medium, without observing the foreseeable poisoning of the catalyst normally caused by sulphur-containing compounds, as are the thiophene derivatives prepared in the present process.
[0052] The general scheme of the process that is the subject of the present invention is given hereinbelow for greater clarity:
[0053] The possible variants of the reduction step (b, b 1 , b 2 ), which are within the scope of the process according to the present invention, are shown in this scheme. The choice of the optimum sequence and of the most advantageous reduction conditions forms part of the normal capabilities of a person skilled in the art.
[0054] One preferred embodiment of the present invention is represented by the preparation of 2,3-dimethyl-5-benzylthiophene (Ia) according to the following scheme:
[0055] In particular, the product IIb may be prepared from the commercially available low-quality compound IIa, by reduction with hydrazine and sodium hydroxide, as described, for example, in WO 99/61435, and used in the next step without being isolated or purified.
[0056] Specifically, the acylation reaction (a) of compound IIb, preferably performed with benzoyl chloride and AlCl 3 , may be performed by directly using its organic extraction solution, which is preferably methylenic, originating from the reduction of compound IIa.
[0057] Compound IVb thus obtained may be totally reduced (b), to give Ia, for example by reaction with sodium borohydride and trifluoroacetic acid or, preferably, subjected to two successive reduction reactions (b 1 and b 2 ) with formation of the hydroxylated intermediate Ic. This latter variant of the process is particularly preferred, since it allows the intermediate Ic to be purified by crystallization.
[0058] In particular, the first reduction reaction (b 1 ) is preferably performed with sodium borohydride and sodium hydroxide, while the second reduction with sodium borohydride and trifluoroacetic acid or by means of catalytic hydrogenation, preferably with sodium borohydride and trifluoroacetic acid. The intermediate Ic is generally crystallized from apolar solvents such as ethers, for example diethyl ether, diisopropyl ether or methyl tert-butyl ether, aromatic hydrocarbons, for example toluene or xylene, or aliphatic hydrocarbons, for example hexane, heptane or cyclohexane, or mixtures of these solvents, preferably from n-heptane.
[0059] The preferred process given in Scheme 4, in particular in its preferred variant, comprising the two successive reduction reactions b 1 and b 2 and the crystallization of the hydroxylated intermediate Ic makes it possible to prepare compound Ia in an overall yield that is comparable with that obtained according to the abovementioned known processes, but avoiding the reagents, reaction conditions and purification techniques of the prior art that are difficult to apply industrially.
[0060] In addition, as mentioned previously, the present process may be applied using the commercially available low-quality product IIa. Specifically, by using compound IIa with a GC purity of 90%, it is possible to obtain 2,3-dimethyl-5-benzylthiophene Ia with an HPLC purity of about 99%, without the need for chromatographic purifications, but merely by means of a simple crystallization of the intermediate alcohol Ic.
[0061] Finally, another preferred embodiment of the present invention is represented by the preparation of compound I according to the following scheme:
[0062] In this case, the product II, in which A represents CHO or R 2 CO—, is acylated directly to give the intermediate IV which is then subjected to the simultaneous reduction of both the carbonyl groups.
[0063] By analogy with that described previously, this conversion may be performed by means of a single reduction reaction (b) or, preferably, two successive reduction reactions (b 1 and b 2 ), with the possibility of purification of the intermediate hydroxylated compound by crystallization.
[0064] One particularly preferred embodiment of this process is the preparation of 2,3-di-methyl-5-benzylthiophene (Ia), from 3-methyl-2-thiophenecarboxaldehyde (IIa, A═CHO, R 1 ═CH 3 ) by acylation (a) with benzoyl chloride, reduction (b 1 ) of compound IVa (A═CHO, R 1 ═CH 3 , R 3 ═H) to the diol Ib (A═CH 2 OH, R 1 ═CH 3 , R 3 ═H), purification thereof by crystallization and subsequent reduction (b 2 ) to give the final compound Ia (A═R 1 ═CH 3 , R 3 ═H).
[0065] The examples that follow will now be given for the purpose of illustrating the present invention more clearly.
EXPERIMENTAL SECTION
Example 1
Preparation of 2,3-dimethylthiophene (IIb, R 1 ═A═CH 3 )
[0066] 3-Methyl-2-thiophenecarboxaldehyde (Aldrich, 90% GC purity) (40 g) was dissolved in diethylene glycol (144 ml) and hydrazine hydrate (62 ml) was added slowly. The reaction mixture was refluxed (about 126° C.) for 30 minutes. The solution was cooled to 30-40° C. and potassium hydroxide (46 g) was then added portionwise. The solution was then slowly heated to reflux and stirred at this temperature for one and a half hours.
[0067] The reaction mixture was cooled to room temperature and poured into cold water (1 L), acidified to pH 2 with concentrated hydrochloric acid (about 150 ml) and extracted with methylene chloride (2×100 ml). The combined organic phases were dried over anhydrous sodium sulphate. The solid was filtered off and washed with methylene chloride (20 ml) and the 2,3-dimethylthiophene solution was used directly without further purification (88.2% GC purity).
Example 2
Preparation of 2,3-dimethyl-5-benzoylthiophene (IVb, R 1 ═A═CH 3 , R 3 ═H)
[0068] Benzoyl chloride (37.2 ml) was dissolved in the methylenic solution containing about 35.6 g of 2,3-dimethylthiophene obtained from Example 1. This solution was added slowly at 0-5° C. to a solution of anhydrous aluminium trichloride (42.7 g) in methylene chloride (100 ml) over 2-3 hours. The reaction mixture was stirred at 20-25° C. for 2 hours and was then refluxed for one hour. After cooling to room temperature, the reaction mixture was poured Into water (500 ml) at 0° C. and stirred for 15 minutes. The two phases were separated and the organic phase was washed first with water (500 ml) and then with aqueous 30% sodium hydroxide solution (30 ml). The organic phase was evaporated under vacuum to give 64.5 g of 2,3-dimethyl-5-benzoylthiophene (94% yield over two steps) (88.8% GC purity).
[0069] 1 H-NMR (300 MHz, DMSO) δ: 7.78 (d, 2H), 7.64 (t, 1H), 7.54 (t, 2H), 7.43 (s, 1H), 2.39 (s, 3H), 2.12 (s, 3H).
Example 3
Preparation of 2,3-dimethyl-5-(α-hydroxybenzyl)thiophene (Ic, R 1 ═A═CH 3 , B═CHOH, R 3 ═H)
[0070] Sodium borohydride (7.0 g) was dissolved in water (40 ml) and 30% sodium hydroxide (2 ml) and this solution was added slowly over about one hour to a solution of 2,3-dimethyl-5-benzoylthiophene (64.5 g) in methanol (250 ml) and 30% sodium hydroxide (3.5 ml). The solution was heated at 35° C. for 6 hours and then refluxed for 2 hours. The reaction mixture was then cooled to 35-40° C. and the methanol was evaporated off under vacuum. The residue was dissolved in water (150 ml), 30% sodium hydroxide (20 ml) and methylene chloride (150 ml). The two phases were separated and the aqueous phase was extracted with methylene chloride (50 ml). The organic phase was evaporated under vacuum and the crude product was dissolved in hot n-heptane (700 ml) and crystallized to give, after drying at 40° C., 46.0 g of 2,3-dimethyl-5-(α-hydroxybenzyl)thiophene (71% yield) (99.1% GC purity).
[0071] m.p.=79-80° C., 1 H-NMR (300 MHz, DMSO) δ: 7.40-7.23 (m, 5H), 6.52 (s, 1H), 6.03 (s, 1H), 5.72 (s, 1H), 2.21 (s, 3H), 1.99 (s, 3H).
Example 4
Preparation of 2,3-dimethyl-5-benzylthiophene Ia, R 1 ═A═CH 3 , B═CH 2 , R 3 ═H)
[0072] 2,3-Dimethyl-5-(α-hydroxybenzyl)thiophene (46.0 g) was dissolved in THF (1100 ml), followed by addition of sodium borohydride (23.9 g). The reaction mixture was cooled to 0° C. and trifluoroacetic acid was added slowly over about two hours at 0-5° C. The reaction mixture was stirred at 0-5° C. for 2 hours. A 30% solution of sodium hydroxide (150 ml) in water (300 ml) was added and the two phases were separated.
[0073] The organic phase was evaporated under vacuum and the residue was dissolved in methylene chloride. The salts were filtered off and the organic solution was washed with aqueous sodium chloride solution and evaporated under vacuum to give 40.5 g of 2,3-dimethyl-5-benzylthiophene as an oil (95% yield) (98.8% HPLC purity).
[0074] 1 H-NMR (300 MHz, DMSO) δ: 7.32-7.20 (m, 5H), 6.54 (s, 1H), 3.99 (s, 2H), 2.21 (s, 3H), 2.02 (s, 3H).
Example 5
Preparation of 2,3-dimethyl-5-benzylthiophene Ia, R 1 ═A═CH 3 , B═CH 2 , R 3 ═H)
[0075] 2,3-Dimethyl-5-(α-hydroxybenzyl)thiophene (46.0 g) was dissolved in methanol (750 ml), followed by addition of 5% palladium-on-charcoal containing 50% water (7.5 g on a dry basis). The reaction mixture was hydrogenated at 40-45° C. and 6-7 bar for 24 hours, to give 26 g of 2,3-dimethyl-5-thiophene (61% yield).
|
The present invention relates to a process for preparing 2,5-disubstituted 3-alkyl-thiophenes and more particularly to a process for preparing them that comprises an acylation reaction in position 5 of 2-substituted 3-alkylthiophenes. This process does not need reagents which are difficult to handle and does not need anhydrous conditions or inert atmosphere. The resulting product is obtained in high purity.
| 2
|
BACKGROUND
1. Field of Invention
The present invention relates to a glove with enhanced gripping capabilities that makes maintaining a grip for a user, less taxing and less fatiguing for the user's hand and forearm muscles. More particularly, the present invention entails a grip-enhancing glove and a method for maintaining a grip that enables a user to maintain a prolonged grip without incurring undesirable effects, as described herein.
2. Background and Related Art
Many sports and other activities require a participant to maintain a prolonged grip around a generally cylindrical object, such as a handle bar. Unfortunately, maintaining such a grip often fatigues the sports participant or user's hand and forearm muscles. In fact, to create a strong grip requires great strength from multiple muscles. Specifically, to form a grip, the flexor muscles of the forearm pull the flexor tendons in the hand. The large amount of tension generated in these muscles and forearm causes hypertrophy, which occurs when the muscles grow in size and fictional capacity to meet the demands placed on it. Thus, prolonged grips and the inability to maintain them becomes a limiting factor for users participating in activities requiring prolonged grips.
Moreover, certain activities cause premature hand and muscle fatigue and consequent grip failure. Grip failure occurs where there is constant direct pressure countering the grip, which eventually forces the grip to open. For example, if a user is strength training and using either a hanging bar or lifting a dumbbell, pressure is continually exerted on the palm of the hand. Eventually, if the force is big enough, it causes the hand to open and the grip to release. Another example involves a user who grips a motorcycle handlebar. While riding, a motorcycle rider, must exert great forces in order to grip and maintain the grip. Specifically, the rider exerts force to hold the bar, must endure the vibration of the bar, and maintain a steady grip for long distance rides. The rider must also vary the pressure to which he or she grips the handlebar, further fostering muscle fatigue.
Many users wear gloves to alleviate the wear and tear on their hands that results from users making prolonged grips. Gloves with non-slip surfaces also provide enhanced gripping capabilities and greater grip strength. However, the problem remains unresolved, and there exists a need, for a glove or method for maintaining a prolonged grip, which enables a user to maintain a grip for an extended period of time, without incurring the undesirable effects of hand wear and tear and hand and forearm muscle fatigue. Moreover, there exists the need for a glove that postpones hand, forearm and muscle fatigue and allows a user to maintain a grip for greater lengths of time and under greater pressures than are possible with available gloves.
SUMMARY AND OBJECTS OF THE INVENTION
Some embodiments of the present invention provide a glove that can be manipulated into a grip position so that a user wearing such a glove is able to maintain the grip for a prolonged period of time, without incurring normally-occurring fatigue resulting from such a prolonged grip.
In a preferred embodiment of the present invention, a glove is provided that has a hand-receiving area, a palmar side, a dorsal side, finger compartments for receiving the user's fingers and cords running either longitudinally and bilaterally along the sides and tip of each finger compartment, or just longitudinally along the palmar-region of the finger compartments. The cords are either integrally connected to the finger compartments, or they are able to move relative to the finger compartments. The cords may also be connected to the finger compartments or to the glove by loop-shaped elements. These loop-shaped elements need not necessarily be circular or looped, yet should be shaped in a way as to receive the generally cylindrically-shaped cords within them. The cords congregate at or around either the wrist or palm region into a gathering and tightening feature. This gathering and tightening feature receives the cords and enables a user to pull the cords downward, through the gathering and tightening feature, toward the wrist thereby drawing the fingers and finger compartments into a grip. The user may then secure the cords by activating the tightening mechanism in the gathering and tightening feature. Once the cords are secure, the fingers are precluded, without user manipulation, from opening into their extended state, and thus, a grip is formed and maintained.
The foregoing description entails the preferred embodiment of the present invention.
In some embodiments of the present invention, where the cords run longitudinally along the palmar side of the finger compartments, they are connected to the finger compartments by horizontal straps as well the loop-shaped elements. These horizontal straps help optimally connect the cords to the glove.
In other embodiments of the present invention, the gathering and tightening feature is located in the palm area of the hand, in other embodiments the dorsal area of the hand, while in other embodiments, it is located below the wrist. In some embodiments, the looped-shaped element is located on each diametric side of the finger compartment at the metacarpophalangeal region.
In some embodiments, the cords are integrally connected to the finger compartments and do not move relative to the glove or the finger compartments. In other embodiments, the loop-shaped elements are interspersed along the finger compartments and the tip of the finger compartments. In this embodiment, the cords are movable relative to the finger compartments. However, in both foregoing embodiments, the cords congregate at a point below the finger compartments and the gathering and tightening feature.
In some embodiments of the present invention the cords are pre-tensioned. That is, in some embodiments of the present invention, the cords have a predetermined strength or rigidity, while in other embodiments, the cords are more flexible. The strength or rigidity of the cords depends on the needs of the user. In some embodiments, the cords may be removed and replaced with cords having different strengths or rigidities.
In other embodiments, some cords may be tightened while others are not, thus varying the amount of fingers and compartments that are forced into the grip.
In some embodiments, the gathering and tightening feature is fabric that receives the cords, wherein the user can somehow secure the cords within the feature or after so that it is precluded from retreating from within the feature and becoming not secure so that the grip is not maintained. In other embodiments, the gathering and tightening feature is a solid mechanism that can secure the cords.
In some embodiments of the present invention, the glove described herein can be used by those who participate in various sports that require a strong, but prolonged grip, such as: mountain-biking; skiing; water-skiing; wind-surfing; or virtually any other sport that requires the hand to grip something.
In another embodiment, the palmar side of the glove is lined with an elastic material that is sewn into place, which causes pre-curving of the glove so that when the hand is inserted into the glove, it is forced into a gripping position, yet the hand can still extend and open as in the other embodiments. The elastic material may be made of different strengths for varying user needs. In some embodiments, any material known to one skilled in the art may be used that causes pre-curving of the glove into a gripping position and also allows for hand extension.
These and other embodiments of the present invention will become more fully apparent from the following description, drawings, and claims. Other embodiments will likewise become apparent from the practice of the invention as set forth hereafter.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects and features of the present invention will become more fully apparent from the accompanying drawings when considered in conjunction with the following description and appended claims. Although the drawings depict only typical embodiments of the invention and are thus, not to be deemed limiting of the invention's scope, the accompanying drawings help explain the invention in added detail.
FIG. 1 depicts one view of one embodiment of the present invention. Specifically,
FIG. 1 shows the glove, as described herein, on a user's hand.
FIG. 2( a ) depicts a similar representation as FIG. 1 , but with the glove as transparent and the cords on the dorsal side of the user's hand. That is, FIG. 2( a ) depicts an embodiment of the present invention wher the glove is transparent so that one only views the cords, and not the glove to which the cords are integrally connected. FIG. 2( b ) again depicts a transparent view of the glove while displaying a non-transparent profile of the cord running alongside the user's finger.
FIG. 3 depicts FIG. 2( a ), again as if the glove was transparent. This figure, though, is a close-up of FIG. 2( a ).
FIGS. 4( a ) and ( b ) are other embodiments of the present invention.
FIGS. 5( a ) and ( b ) are even other embodiments of the present invention.
FIG. 6 is yet another embodiment of the present invention.
FIGS. 7( a ), ( b ) and ( c ) depicts the embodiment represented in FIG. 1 , but in a gripped position.
FIG. 8( a ) shows a top view of one embodiment of the present invention while FIG. 8( b ) shows the top view of another embodiment.
FIG. 9 shows to positions of the embodiments of the present invention herein disclosed.
DETAILED DESCRIPTION OF THE INVENTION
It is emphasized that the present invention, as illustrated in the figures and description herein, can be embodied in other forms. Thus, neither the drawings nor the following more detailed description of the various embodiments of the system and method of the present invention limit the scope of the invention. The drawings and detailed description are merely representative of the particular embodiments of the invention; the substantive scope of the present invention is limited only by the appended claims. The various embodiments of the invention will best be understood by reference to the drawings, wherein like elements are designated by like alphanumeric character throughout.
With reference now to the accompanying drawing, FIG. 1 depicts one view of one embodiment of the present invention. Specifically, FIG. 1 shows a user's hand 12 in a glove 10 , which is the subject of the present invention. This view is of the palmar side of the hand 12 . In this embodiment, the cords 14 that are integrally connected to the glove 10 , dangle below the wrist 16 . However, in other embodiments they might not be exposed or covered by a gathering and tightening feature 36 . (shown later) This gathering and tightening feature 36 may comprise a fastener, a lock, or a patch of fabric with securing capabilities, which precludes the cords 14 from becoming unsecured without activation from the user.
FIG. 2( a ) depicts a similar representation as FIG. 1 , but with the glove 10 as transparent and the cords 14 on the dorsal side of the user's hand. That is, FIG. 2( a ) depicts an embodiment of the present invention where the glove 10 is transparent so that only the cords 14 are viewable, and not the glove 10 to which the cords 14 are integrally connected. This figure also depicts the dorsal side 13 of the user's hand 12 . In contrast, the palmar side 11 is on the opposite side of the dorsal side 13 and is not viewable in this figure. In this embodiment, the cords 14 run bilaterally along the diametric sides 20 of finger compartments 22 that receive a user's finger 24 . The cords 14 are integrally attached to the glove 10 at certain areas, but not at other areas. This will be more fully explained below. Moreover, the finger compartments 22 are part of the glove 10 , and because the fingers 24 are substantially cylindrical, four different areas of the finger 24 will be identified and referred to in order to demonstrate where the cords 14 connect with the glove 10 . These areas are best illustrated in FIG. 2( b ).
FIG. 2( b ) depicts a transparent side view of the user's finger 24 with the cord 14 running alongside. As mentioned above, the finger compartments 22 receiving the finger 24 , which are transparent in this Figure, have four sides: a dorsal-region 26 that is on the same plane as the dorsal side 13 of the glove 10 ; a palmar-region 28 , diametric sides 20 ; and a tip 30 . The diametric sides 20 are, as their name suggests, opposite one another. Put another way, the diametric sides 20 are on the sides of the finger 24 , which are not the dorsal-region 26 or the palmar-region 28 .
Returning now to FIG. 2( a ), the cords 14 that run alongside the diametric sides 20 of the finger compartments 22 may be connected to the glove 10 in a variety of ways. However, the way displayed in the embodiment shown in FIG. 2( a ), depicts loop-shaped elements 32 that receive the cords 14 at the area where the cords 14 are not integrally connected to the diametric sides 20 of the glove 10 . Specifically, the cords 14 run through these loop-shaped elements 32 at a region known as the metacarpophalangeal joint region 34 . Though their name conveys otherwise, these loop-shaped elements 32 do not necessarily need to be circular, but shaped in a way as to enable the cylindrically-shaped cords 14 to move within them, relative to the glove 10 . That is, the loop-shaped elements 32 enable the cords 14 to move back and forth within them. This motion enables the user to pull and release the cords, thereby enabling and releasing the grip, respectively.
Thus, in FIG. 2( a ) the cords 14 are integrally connected to the glove 10 as they run longitudinally and bilaterally along the diametric sides 20 of the finger compartments 22 . At the metacarpophalangeal joint region 34 , though, the cords 14 become no longer integrally connected to the glove 10 and are received within the loop-shaped elements 32 where they ( 14 ) are movable relative to the glove 10 . The cords 14 are then congregated into a gathering and tightening feature 36 . A user may then pull the cords 14 , which forces the fingers 24 within the finger compartments 22 to curl toward the palm 48 of the glove 10 and thereby, to form a grip. The user may then secure the cords 14 by either activating the gathering and tightening feature 36 so that the tightening portion of the gathering and tightening feature 36 secures the cords. Alternatively, the cords 14 can be tied so that the grip is maintained. Other ways to secure the cords 14 may be used, such as by using clamps, fasteners, and any other device or mechanism (all of which may be incorporated into the gathering and tightening feature 36 ), which prevents the cords 14 from retreating back through the loop-shaped elements 32 and thereby, causing the grip to release.
Thus, as described in the background section, pulling the cords 14 and enabling the gathering and tightening feature 36 allows users desiring a prolonged grip, to have such a grip, yet relax their hand in the grip so as to not overuse muscles within the hand and forearm. Moreover, such a “forced” grip mitigates the potential for hand and muscle fatigue often associated with those sports activities or activities where users maintain a prolonged grip.
FIG. 3 depicts FIG. 2( a ) again as if the glove was transparent. This figure, though, is a close-up of the loop-shaped elements 32 that integrally connect the cords to the glove and the gathering and tightening feature 36 . Similarly to FIG. 2( a ), in this embodiment, the cords 14 slide through the loop-shaped elements 32 , with relative motion to the glove 10 , when the user pulls the cords 14 so a grip is formed and secured.
FIGS. 4( a ) and ( b ), 5 ( a ) and ( b ), and 6 depict other embodiments of the present invention that allow the user to maintain a grip. Specifically, 4 ( a ) depicts an alternative embodiment of the present invention where the cords 14 , unlike in FIGS. 2 and 3 , do not gather at a gathering and tightening feature 36 , but instead run through loop-shaped elements 32 located closer to the wrist 16 . Similarly to FIGS. 2 and 3 , the cords 14 run longitudinally and bilaterally along the diametric sides 20 of the finger compartments 22 , but in this embodiment they are not integrally connected to the diametric sides 20 of the finger compartments 22 . Rather, the cords 14 are able to move relative to the finger compartments 22 through loop-shaped elements that are interspersed along the finger compartments 22 . In this specific embodiment, the loop-shaped elements 32 may be placed at the distal interphalangeal joint 40 , the proximal interphalangeal joint 42 , and perhaps even again at the metacarpophalangeal joint region 34 . To optimize the way the cords 14 run through the loop-shaped elements 32 and to ensure that the cords 14 are sufficiently integrally connected with the glove 10 , locations for the loop-shaped elements 32 are depicted in 4 ( b ). FIG. 4( b ) is a view of one diametric side 20 of a finger compartment 22 and illustrates possible locations for the loop-shaped elements 32 that receive the cords 14 . For instance, one loop-shaped element 32 may be placed at the distal interphalangeal joint 40 on the palmar-side 28 of the finger compartments 22 , while another is at the dorsal-side 28 of the finger compartments 22 . Yet another can be placed at the metacarpophalangeal joint region 34 on the dorsal side 13 . Similarly, the foregoing placement of the loop-shaped elements 32 would be at the other diametric side 20 of the same finger compartment 22 . Also shown in 4 ( a ) and 4 ( b ) are loop-shaped elements 32 found at the tip 30 of the finger compartment 22 .
Again, in FIG. 4( a ) rather than the cords being integrally connected along the diametric sides 20 of the finger compartments 22 , the cords 14 are able to move relative to glove 10 and the finger compartments 22 . The loop-shaped elements 32 are also found near the wrist 16 , showing how in various embodiments of the present invention the cords may be longer or shorter depending on the placement of the gathering and tightening feature 36 . FIG. 4( a ) shows the gathering and tightening feature 36 would be located below the loop-shaped elements 32 and below the wrist 16 .
In all the above embodiments, the cord 14 may be exposed on the outside of the glove 10 , located within the glove 10 , or layered between two pieces of fabric integrally connected to the glove 10 . Again, the cords 14 may be integrally secured to the diametric sides 20 of the finger compartments 22 or unconnected so that they may move relative to the finger compartments 22 .
Another embodiment is shown in FIG. 5( a ). In this Figure, the cords 14 connect after the metacarpophalangeal joint region 34 to form one combined cord 42 that then runs to a gathering and tightening feature 36 . Again in this figure, the cord 14 may be covered by stitches 44 that help integrally connect the cords to the finger compartments 22 . FIG. 5( b ) is a profile view of 5 ( a ).
In other embodiments not shown in figures, the gathering and tightening feature 36 might be activated by a hydraulic piston.
FIG. 6 depicts another embodiment of the present invention. Similarly to FIG. 2 , this depiction makes the glove transparent so only the cords are viewable. FIG. 6 displays the cords 14 running alongside the palmar-region 28 of the finger compartments of the palmar side 11 of the glove 10 . That is, the cords 14 are not on the diametric sides 20 , or bilaterally placed on the finger compartments 22 , but rather, run along the palmar-side 28 of the finger compartments 22 . The loop-shaped elements 32 are also placed differently. Similarly to the cords 14 , in this embodiment, they run in vertical alignment with the finger compartments 22 . The cords are secured by horizontal straps 46 that are received by the loop-shaped elements 32 . The horizontal straps 46 run from one diametric side 20 to the other 20 so they can be received within the loop-shaped elements 32 in order to help integrally connect the cords 14 to the finger compartments 22 . The cords 14 in this embodiment run from below the tip 30 , or even on the tip 30 , vertically downward toward and below the wrist 16 . They are not attached at the palm 48 , but rather, around the wrist 16 , so that they may be pulled by a user to draw the finger compartments 22 down and force the glove 10 into a grip.
FIG. 7( a ) depicts the embodiment represented in FIG. 1 , but in a gripped position. That is, in this Figure, the user's hand is contracted inward and the fingers 24 (and corresponding finger compartments 22 ) are pulled toward the palm 48 resulting in a grip. The present invention, therefore, enables a user to maintain a gripped position, without having to heavily rely on the hand and arm muscles to maintain the grip. FIGS. 7( b ) and 7 ( c ) depict two side views of the user's hand in the glove: 7 ( b ) depicting the hand gripping a cylindrical object while 7 ( c ) depicts the hand in gripping position without the cylindrical object.
FIG. 8( a ) shows a top view of one embodiment of the present invention displaying the tip 30 of the finger compartment 22 with the cord 14 running along the tip 30 and along the diametric sides 20 of the finger compartment 22 . This is the embodiment depicted in FIG. 2 . FIG. 8( b ) shows an alternative embodiment where the cord 14 aligns the palmar-side 28 of the finger compartments 22 (not shown.)
FIG. 9 shows two positions of the embodiments of the present invention herein disclosed. In position (a) the glove 10 is in the initial position, where the fingers of a user are protruded and extended and the palm 48 is opened and flat. Position (b) demonstrates the cords 14 having been pulled by the user and thereby, creating a grip. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
|
A glove with enhanced gripping capabilities that makes maintaining a grip for a user, less taxing and less fatiguing for the user's hand and forearm muscles. More particularly, a grip-enhancing glove, and method for maintaining a grip, which enables a user to maintain a prolonged grip without incurring undesirable effects.
| 0
|
BACKGROUND OF THE INVENTION
This invention relates to an optical lens for use in an optical head for reading an optical disk, and in particular, to a lens coating in relation to a high-precision mounting of an optical lens to an optical head with a use of a reflected light of a laser beam from a lens.
In a conventional optical lens for use in an optical head for reading an optical disk, a reflection preventing coating (hereinafter referred to also as a coat) is provided at each of a light-incident surface into which light comes and a light-outgoing surface from which the incident light is emitted and a laser beam of 780 nm is used as a passing light for the lens. Further, the optical characteristic of the reflection preventing coat provided on each of the light-incident surface (S 1 ) and the light-outgoing surface (S 2 ) of an optical lens is such one as shown in FIG. 1 .
FIG. 1 is a drawing for explaining a conventional example of a coat (reflection preventing coat); FIG. 1 ( a ) is an illustration of the layer structure of the coat on the surface S 1 and the surface S 2 , and FIG. 1 ( b ) is a drawing showing the reflectance (spectral reflectance) vs. the wavelength of light.
Moreover, the reflectance R (%) on the ordinate in FIG. 1 and in FIG. 2 to FIG. 7 which are described below is represented in logarithmic scale for the convenience of preparing the drawings. (Only in the last FIG. 8, the ordinate is represented with divisions of equal intervals.)
The layer structure of the reflection preventing coat of the light-incident surface (S 1 ) and the light-outgoing surface (S 2 ) (for light having a wavelength of 780 nm) is made such one as stated below. Further, for a substrate material, a resin material such as an acrylic resin, “Arton” resin, “Zeonex” resin, or a polycarbonate resin is used.
First layer: cerium oxide (refractive index n≠2.03) layer thickness d≠34 nm
Second layer: silicon oxide (refractive index n≠1.45) layer thickness d≠177 nm
With respect to the position adjustment in mounting an optical lens to an optical reading head, a lens which has been coated with reflection preventing coats is fitted in an optical reading head, and a He—Ne laser beam having a wavelength of 633 nm is irradiated through this lens, and the position adjustment is done by utilizing the reflected light.
However, as shown in FIG. 1, the reflectance for the wavelength 633 nm of a He—Ne laser beam is as low as 4.3%, and there has been the problem that a high precision can not be obtained in the position adjustment of the lens.
SUMMARY OF THE INVENTION
This invention has been made in order to solve the above-mentioned problem. That is, it is an object of the invention to provide means for improving the precision of the position adjustment of the lens, by preventing the lowering of the intensity of transmitting light having the wavelength (λ T ) and by raising the reflectance of the surface S 2 for the wavelength (λ R ) of the light for the position adjustment.
The object of this invention can be accomplished by employing any one of the structures described below.
That is, in an optical lens to be used for a passing light having the maximum intensity at the wavelength (λ T ) 780±10 nm, an optical component is made such that both or at least one of a light-incident surface (S 1 ) and a light-outgoing surface (S 2 ) is provided with a reflection preventing coating and the following inequality is satisfied:
R 2 (λ R )> R 1 (λ R ),
where R 1 (λ R ) and R 2 (λ R ) denote the reflectance of the respective surfaces for a light having a wavelength (λ R ) falling within a range from 500 to 700 nm.
Further, in an optical lens to be used for a passing light having the maximum intensity at a wavelength (λ T ) falling within a range from 600 to 700 nm, an optical component is made such that both or at least one of the light-incident surface (S 1 ) and the light-outgoing surface (S 2 ) is provided with a reflection preventing coating, and the following inequality is satisfied:
R 2 (λ R )> R 1 (λ R ),
where R 1 (λ R ) and R 2 (λ R ) denote the reflectance of the respective surfaces for a light having a wavelength (λ R ) falling within a range from 750 to 850 nm.
Further, in an optical lens to be used for a passing light having the maximum intensity at a wavelength falling within a range from 350 to 500 nm, an optical component is made such that both or at least one of the light-incident surface (S 1 ) and the light-outgoing surface (S 2 ) is provided with a reflection preventing coating, and the following inequality is satisfied:
R 2 (λ R )> R 1 (λ R ),
where R 1 (λ R ) and R 2 (λ R ) denote the reflectance of the respective surfaces for a light having a wavelength (λ R ) within a range from 500 to 800 nm.
Further, the reflectance R 2 (λ R ) of the light-outgoing surface (S 2 ) of the optical component is made not smaller than 5% for the wavelength (λ R ).
For example, these are as follows.
(1) When the transmittance T(λ T ) for a laser beam having a peak intensity at the wavelength (λ T ) 780 nm is made 96% or more and the wavelength (λ R ) falls within a range from 500 to 700 nm, desirably is the wavelength of 633 nm of a He—Ne laser beam, the following conditional formula is satisfied:
R 1 (λ R )< R 2 (λ R ),
where R 1 (λ R ) and R 2 (λ R ) denote the reflectance of the light-incident surface and the light-outgoing surface respectively.
(2) When a lens is fitted in a pickup for an optical disk player, light is irradiated to the surface S 2 of the lens and the position adjustment in the fitting is done by detecting the reflected light. Assuming that the wavelength of the reflected light is λ R , the yield of assembly in the fitting greatly depend upon the reflectance R 2 (λ R ) of the surface S 2 for light having the wavelength λ R . In the case where R 2 (λ R )≧5%, the yield of 88% or more can be obtained, and in the case where R 2 (λ R )≧7%, the yield of 95% or more can be obtained. In order to make the expense of assembly smaller as far as possible, it is necessary to raise the yield as much as possible; it is required at least that R 2 (λ R )≧5%, and it is desirably required that R 2 (λ R )≧7%.
This invention is capable of solving these requirements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 ( a ) and FIG. 1 ( b ) are drawings for explaining an example of a conventional coat.
FIG. 2 ( a ), FIG. 2 ( b ), FIG. 2 ( c ), and FIG. 2 ( d ) are drawings for explaining the coat of Embodiment 1.
FIG. 3 ( a ), FIG. 3 ( b ), and FIG. 3 ( c ) are drawings for explaining the coat of Embodiment 2.
FIG. 4 ( a ), FIG. 4 ( b ), and FIG. 4 ( c ) are drawings for explaining the coat of Embodiment 3.
FIG. 5 ( a ), FIG. 5 ( b ), and FIG. 5 ( c ) are drawings for explaining the coat of Embodiment 4.
FIG. 6 ( a ), FIG. 6 ( b ), and FIG. 6 ( c ) are drawings for explaining the coat of Embodiment 5.
FIG. 7 ( a ), FIG. 7 ( b ), and FIG. 7 ( c ) are drawings for explaining the coat of Embodiment 6.
FIG. 8 is a drawing for explaining the coat of Embodiment 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In the following, examples of practice will be shown.
Embodiment 1
FIG. 2 are drawings for explaining the coat of Embodiment 1; FIG. 2 ( a ) is an illustration of the structure of the coat layer of the surface S 1 , FIG. 2 ( b ) is an illustration of the structure of the coat layer of the surface S 2 , FIG. 2 ( c ) is a drawing showing a typical reflectance of the surface S 1 vs. light wavelength, and FIG. 2 ( d ) is a drawing showing a typical reflectance of the surface S 2 vs. light wavelength.
For the base material in Embodiment 1, any one out of an acrylic resin, “Arton” resin, “Zeonex” resin, and a polycarbonate resin is used.
Reflection preventing coat of the surface S 1
(herer, n ij : the refractive index of the j-th layer of the surface S i , d ij : the layer thickness (mm) of the j-th layer of the surface S i , i: 1 or 2, j: an integer)
First layer: cerium oxide (refractive index n 11 ≠2.03) layer thickness d 11 =340 ű30 Å
Second layer: silicon oxide (refractive index n 12 ≠1.45) layer thickness d 12 =1770 ű150 Å
Reflection preventing coat of the surface S 2
First layer: cerium oxide (refractive index n 21 ≠2.03) layer thickness d 21 =395 ű15 Å
Second layer: silicon oxide (refractive index n 22 ≠1.45) layer thickness d 22 =2075 ű75 Å
In the vacuum deposition method, heating by an electronic gun is employed. For the evaporation source, a pellet of cerium oxide or particles of silicon oxide are placed. Oxide gas is introduced with its pressure made to be 1.5×10 −2 pas to carry out the vacuum deposition.
Effect
In this way, the following result was obtained.
As shown in FIG. 2 ( c ) and FIG. 2 ( d ), for the reflectance of 4.3% of the surface S 1 for the wavelength 633 nm of the laser beam for the position adjustment, the reflectance of the surface S 2 was 9.8%, which is larger than the conventional one, thereby making it possible to improve the precision of the position adjustment. Further, the transmittance for the passing laser beam having the wavelength of 780 nm was kept at 96% or more.
The summary of the results is as follows:
Transmittance T(λ T )≧96%
(λ T : wavelength of a laser beam having the maximum intensity at 780 nm)
R 1 (λ R )=1.5% to 7.0%
(λ R : wavelength of a light having the maximum intensity at 633 nm (He—Ne laser beam))
R 2 (λ R )=9.7% to 13.0%
(λ R : the same as the above).
In this way, as the transmittance for the passing laser beam for use in an optical head having the above-mentioned wavelength, 96% or more could be secured. Further, the reflectance R 2 (λ R ) of the light-outgoing surface of the lens (S 2 ) for the laser beam for the position adjustment of the lens was 9.7% to 13.0%, which is larger than 4.3% of the conventional example; thus, it has become possible that a reflectance of at least 5% or more is secured and the reflectance R 2 (λ R ) is made larger than the reflectance R 1 (λ R ) of the light-incident surface of the lens (S 1 ) which is 1.5% to 7.0%, thereby improving the precision and the easiness of operation of the position adjustment of the lens as will be explained later in Embodiment 7.
Embodiment 2
FIG. 3 are drawings for explaining the coat of Embodiment 2; FIG. 3 ( a ) is an illustration of the structure of the coat layer of the surface S 1 , FIG. 3 ( b ) is an illustration of the structure of the coat layer of the surface S 2 , and FIG. 3 ( c ) is a drawing showing a typical reflectance of the surface S 2 vs. light wavelength.
The base material of Embodiment 2 is the same as Embodiment 1.
Further, for the coat of the surface S 1 , the same one as Embodiment 1 is used.
Reflection preventing coat of the surface S 2
First layer: silicon oxide (refractive index n 21 ≠1.45) layer thickness d 21 =1480 ű80 Å
Second layer: cerium oxide (refractive index n 22 ≠2.03) layer thickness d 22 =530 ű30 Å
Third layer: silicon oxide (refractive index n 23 ≠1.45) layer thickness d 23 =1840 ű90 Å
The method of vapor deposition is the same as Embodiment 1.
Effect
In this way, the following result was obtained.
As shown in FIG. 3, by making up the coat of the surface S 2 of three layers, the reflectance of the surface S 2 for the wavelength 633 nm of the laser beam for the position adjustment became higher to 13%.
Further, it was accomplished to make the transmittance T(780 nm) 96% or more, which is practically of no problem, and the precision of the position adjustment was improved more than Embodiment 1.
The summary of the results is as follows:
Transmittance T(λ T )≧96%
(λ T : wavelength of a laser beam having the maximum intensity at 780 nm)
R 2 (λ R )=9.0% to 16.0%
(λ R : wavelength of a laser beam having the maximum intensity at 633 nm).
In this way, as the transmittance of the optical head for the passing laser beam for use as an optical head having the above-mentioned wavelength, 96% or more could be secured. Further, the reflectance R 2 (λ R ) of the light-outgoing surface (S 2 ) of the lens for the laser beam for the position adjustment of the lens was 9.0% to 16.0%, which is larger than 4.3% of the conventional example; thus, it has become possible that a reflectance of at least 5% or more is secured and the reflectance R 2 (λ R ) is made larger than Embodiment 1, thereby improving the precision and the easiness of operation of the position adjustment of the lens as will be explained later in Embodiment 7.
Embodiment 3
FIG. 4 are drawings for explaining the coat of Embodiment 3; FIG. 4 ( a ) is an illustration of the structure of the coat layer of the surface S 1 , FIG. 4 ( b ) is an illustration of the structure of the coat layer of the surface S 2 , and the broken line and the solid line in FIG. 4 ( c ) are curves showing a typical reflectance of the surface S 1 and S 2 vs. light wavelength respectively.
The base material of Embodiment 3 is the same as Embodiment 1.
Reflection preventing coat of the surface S 1
First layer: cerium oxide (refractive index n 11 ≠2.03) layer thickness d 11 =283 ű28 Å
Second layer: silicon oxide (refractive index n 12 ≠1.45) layer thickness d 12 =1470 ű150 Å
Reflection preventing coat of the surface S 2
First layer: silicon oxide (refractive index n 21 ≠1.45) layer thickness d 21 =920 ű70 Å
Second layer: cerium oxide (refractive index n 22 ≠2.03) layer thickness d 22 =328 ű28 Å
Third layer: silicon oxide (refractive index n 23 ≠1.45) layer thickness d 23 =1140 ű90 Å
The method of vapor deposition is the same as Embodiment 1.
Effect
In this way, the following result was obtained:
Transmittance T(λ T )≧96%
(λ T : wavelength of a laser beam having the maximum intensity at 650 nm)
R 1 (λ R )=0.5% to 2.8%
(λ R : wavelength of a laser beam having the maximum intensity at 780 nm)
R 2 (λ R )=5.1% to 6.8%
(λ R : the same as the above).
In this way, as the transmittance of the optical head for the passing laser beam for use as an optical head having the above-mentioned wavelength, 96% or more could be secured. Further, the reflectance R 2 (λ R ) of the light-outgoing surface (S 2 ) of the lens for the laser beam for the position adjustment of the lens was 5.1% to 6.8%; thus, it has become possible that a reflectance of at least 5% or more is secured and the reflectance R 2 (λ R ) is made larger than the reflectance R 1 (λ R ) of the light-incident surface (S 1 ) of the lens which is 0.5% to 2.8%, thereby improving the precision and the easiness of operation of the position adjustment of the lens as will be explained later in Embodiment 7.
Embodiment 4
FIG. 5 are drawings for explaining the coat of Embodiment 4; FIG. 5 ( a ) is an illustration of the structure of the coat layer of the surface S 1 , FIG. 5 ( b ) is an illustration of the structure of the coat layer of the surface S 2 , and FIG. 5 ( c ) is a drawing showing a typical reflectance of the surface S 2 vs. light wavelength.
The base material of Embodiment 4 is the same as Embodiment 1.
Reflection preventing coat of the surface S 1
First layer: cerium oxide (refractive index n 11 ≠2.03) layer thickness d 11 =283 ű28 Å
Second layer: silicon oxide (refractive index n 12 ≠1.45) layer thickness d 12 =1470 ű150 Å
(the reflection preventing coat of the surface S 1 is the same as Embodiment 3)
Reflection preventing coat of the surface S 2
First layer: cerium oxide (refractive index n 21 ≠2.03) layer thickness d 21 =1370 ű95 Å
Second layer: silicon oxide (refractive index n 22 ≠1.45) layer thickness d 22 =1490 ű104 Å
Third layer: cerium oxide (refractive index n 23 ≠2.03) layer thickness d 23 =1010 ű70 Å
Fourth layer: silicon oxide (refractive index n 24 ≠1.45) layer thickness d 24 =834 ű58 Å
The method of vapor deposition is the same as Embodiment 1.
Effect
In this way, the following result was obtained:
Transmittance T(λ T )≧96%
(λ T : wavelength of a laser beam having the maximum intensity at 650 nm)
R 1 (λ R )=0.5% to 2.8%
(λ R : wavelength of a laser beam having the maximum intensity at 780 nm)
R 2 (λ R )=6.0% to 25.0%
(λ R : the same as the above).
In this way, as the transmittance of the optical head for the passing laser beam for use as an optical head having the above-mentioned wavelength, 96% or more could be secured. Further, the reflectance R 2 (λ R ) of the light-outgoing surface (S 2 ) of the lens for the laser beam for the position adjustment of the lens was 6.0% to 25.0%, which is larger than 4.3% for the example of conventional one; thus, it has become possible that a reflectance of at least 5% or more is secured, the reflectance R 2 (λ R ) is made larger than the reflectance R 1 (λ R ) of the light-incident surface (S 1 ) of the lens which is 0.5% to 2.8%, and it is made greatly higher than the example of the practice 3 , thereby improving the precision and the easiness of operation of the position adjustment of the lens as will be explained later in Embodiment 7.
Embodiment 5
FIG. 6 are drawings for explaining the coat of Embodiment 5; FIG. 6 ( a ) is an illustration of the structure of the coat layer of the surface S 1 , FIG. 6 ( b ) is an illustration of the structure of the coat layer of the surface S 2 , and the broken line and the solid line in FIG. 6 ( c ) are curves showing a typical reflectance of the surface S 1 and S 2 vs. light wavelength respectively.
The base material of Embodiment 5 is the same as Embodiment 1.
Reflection preventing coat of the surface S 1
First layer: cerium oxide (refractive index n 11 ≠2.03) layer thickness d 11 =174 ű21 Å
Second layer: silicon oxide (refractive index n 12 ≠1.45) layer thickness d 12 =898 ű110 Å
Reflection preventing coat of the surface S 2
First layer: silicon oxide (refractive index n 21 ≠1.45) layer thickness d 21 =680 ű65 Å
Second layer: cerium oxide (refractive index n 22 ≠2.03) layer thickness d 22 =258 ű25 Å
Third layer: silicon oxide (refractive index n 23 ≠1.45) layer thickness d 23 =849 ű84 Å
The method of vapor deposition is the same as Embodiment 1.
Effect
In this way, the following result was obtained:
Transmittance T(λ T )≧96%
(λ T : wavelength of a laser beam having the maximum intensity at 408.3 nm)
R 1 (λ R )=4. 0% to 5.5%
(λ R : wavelength of a laser beam having the maximum intensity at 633 nm)
R 2 (λ R )=6.0% to 7.5%
(λ R : the same as the above).
In this way, as the transmittance of the optical head for the passing laser beam for use as an optical head having the above-mentioned wavelength, 96% or more could be secured. Further, the reflectance R 2 (λ R ) of the light-outgoing surface (S 2 ) of the lens for the laser beam for the position adjustment of the lens was 6.0% to 7.5%, which is larger than 5.0% for the example of conventional one; thus, it has become possible that the reflectance R 2 (λ R ) is made larger than the reflectance R 1 (λ R ) of the light-incident surface (S 1 ) of the lens which is 4.0% to 5.5%, thereby improving the precision and the easiness of operation of the position adjustment of the lens as will be explained later in Embodiment 7.
Embodiment 6
FIG. 7 are drawings for explaining the coat of Embodiment 6; FIG. 7 ( a ) is an illustration of the structure of the coat layer of the surface S 1 , FIG. 7 ( b ) is an illustration of the structure of the coat layer of the surface S 2 , and the broken line and the solid line in FIG. 7 ( c ) are curves showing a typical reflectance of the surface S 1 and S 2 vs. light wavelength respectively.
The base material of Embodiment 6 is the same as Embodiment 1.
Reflection preventing coat of the surface S 1
First layer: cerium oxide (refractive index n 11 ≠2.03) layer thickness d 11 =174 ű17 Å
Second layer: silicon oxide (refractive index n 12 ≠1.45) layer thickness d 12 =898 ű89 Å
Reflection preventing coat of the surface S 2
First layer: zirconium oxide (refractive index n 21 ≠2.03) layer thickness d 21 =910 ű90 Å
Second layer: silicon oxide (refractive index n 22 ≠1.45) layer thickness d 22 =982 ű95 Å
Third layer: zirconium oxide (refractive index n 23 ≠2.03) layer thickness d 23 =645 ű64 Å
Fourth layer: silicon oxide (refractive index n 24 ≠1.45) layer thickness d 24 =548 ű54 Å
The method of vapor deposition is the same as Embodiment 1.
Effect
In this way, the following result was obtained:
Transmittance T(λ T )≧96%
(λ T : wavelength of a laser beam having the maximum intensity at 408.3 nm)
R 1 (λ R )=4.0% to 5.5%
(λ R : wavelength of a laser beam having the maximum intensity at 633 nm)
R 2 (λ R )=30.0% to 36.5%
(λ R : the same as the above).
In this way, as the transmittance of the optical head for the passing laser beam for use as an optical head having the above-mentioned wavelength, 96% or more could be secured. Further, the reflectance R 2 (λ R ) of the light-outgoing surface (S 2 ) of the lens for the laser beam for the position adjustment of the lens was 30.0% to 36.5%, which is larger than 4.3% for the example of conventional one; thus, it has become possible that the reflectance is made larger than the reflectance R 1 (λ R ) of the light-incident surface (S 1 ) of the lens which is 4.0% to 5.5%, and it is made greatly higher than the example of the practice 5 , thereby improving the precision and the easiness of operation of the position adjustment of the lens as will be explained later in Embodiment 7.
Embodiment 7
FIG. 8 is a drawing for explaining the coat of Embodiment 7; it is a drawing showing curves of the reflectance of the surface S 2 of a lens, of which the reflection preventing coat of the surface S 1 and the surface S 2 in Embodiment 1 is made up in such a manner as shown in Table 1 below, vs. wavelength of light.
In addition, the ordinate of this FIG. 8, the reflectance R(%) is represented in equal-interval scale, which is different from FIG. 1 to FIG. 7 as described in the above.
TABLE 1
Reflection
preventing
Kind of reflection preventing
coat of
coat of surface S2
surface S1
1
2
3
4
5
1st layer
Coat
d 11
d 21
cerium
No.
oxide
(Å)
340
318
326
344
357
387
2nd layer
Coat
d 12
d 22
silicon
No.
oxide
(Å)
1770
1656
1700
1793
1862
2023
λ R
790
820
Reflectance in
a
b
c
d
e
f
FIG. 8
Further, in Table 2 described below, the reflectance, the transmittance, the yield in assembly, and the judgment whether it is good or bad for practical use are shown for the case where the reflection preventing coat of the surfaces S 1 and S 2 is formed in each of the combinations shown in the above-mentioned Table 1. Besides, the wavelength λ R of the laser beam for the position adjustment of the lens is 633 nm, and the wavelength λ T of the passing laser beam for use in an optical head is 780 nm.
TABLE 2
Kind of reflection preventing coat of surface S2
1
2
3
4
5
R 1 (λ R ) (%)
4.3
4.3
4.3
4.3
4.3
R 2 (λ R ) (%)
2.3
3.0
5.0
7.0
11.0
T (λ T ) (%)
97.8
98.0
98.2
97.2
96.8
Yield (%)
70
75
88
95
98
Evaluation
C
C
B
A
A
As shown in Table 2, when the reflectance R 2 (λ R ) of the kind 1 and the kind 2 of the reflection preventing coat of the surface S 2 is 2.3% and 3.0% respectively which are smaller than the reflectance R 1 (λ R ) 4.3% of the surface S 1 , the assembly yield becomes 70% and 75% respectively, which do not make the practical quality come up to the standard, because the position adjustment using the reflected light by the surface S 2 becomes hard to observe owing to insufficient illumination.
When the reflectance R 2 (λ R ) of the kind 3 of the coat of the surface S 2 is 5.0% which is larger than the reflectance R 1 (λ R ) 4.3% of the surface S 1 , resulting in the assembly yield of 88%, the practical quality comes up to the standard, because the position adjustment using the reflected light by the surface S 2 becomes easy to observe owing to sufficient illumination which improves the precision of position adjustment and the easiness of operation.
Further, when the reflectance R 2 (λ R ) of the kind 4 and kind 5 of the coat of the surface S 2 are 7.0% and 11.0% respectively which are larger than the reflectance R 1 (λ R ) 4.3% of the surface S 1 , and when the value of the reflectance R 2 (λ R ) becomes larger 7.0% to 11.0%, the assembly yield becomes 95% to 98% which come near to almost 100% and the practical quality comes sufficiently up to the standard, because the position adjustment using the reflected light by the surface S 2 becomes easy to observe owing to sufficient illumination which improves the precision of position adjustment and the easiness of operation. Accordingly, if the reflectance R 2 (λ R ) of the surface S 2 is larger than the reflectance R 1 (λ R ) of the surface S 1 , and in particular, if the reflectance R 2 (λ R ) of the surface S 2 is so large as to get a value described in the above, the assembly yield becomes nearly 100% owing to the improvement of the precision of the position adjustment and the easiness of operation as described in the above; that is very desirable.
According to this invention, it has become possible to provide means for preventing the lowering of the intensity of the transmitted light for the wavelength (λ T ), for raising the reflectance of the surface S 2 for the wavelength (λ R ) of the light for the position adjustment, and for improving the precision of the position adjustment of the lens.
|
In an optical lens used for a passing light having the maximum intensity on a wavelength (λ T ) of 780±10 nm, an optical is made such that a reflection preventing coating is provided on both or at least one of a light-incident surface (S 1 ) and a light-outgoing surface (S 2 ) and the following conditional formula is satisfied: R 2 (λ R )>R 1 (λ R ), where R 1 (λ R ) and R 2 (λ R ) are a reflectance of said respective surfaces for light having a wavelength (λ R ) falling within a range from 500 to 700 nm.
| 6
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for fabricating semiconductor device, and more particularly, to a method of using ion implantations to form interface layer in a gate structure.
2. Description of the Prior Art
In current semiconductor industry, polysilicon has been widely used as a gap-filling material for fabricating gate electrode of metal-oxide-semiconductor (MOS) transistors. However, the conventional polysilicon gate also faced problems such as inferior performance due to boron penetration and unavoidable depletion effect which increases equivalent thickness of gate dielectric layer, reduces gate capacitance, and worsens driving force of the devices. In replacing polysilicon gates, work function metals have been developed to serve as a control electrode working in conjunction with high-K gate dielectric layers.
Nevertheless, as semiconductor technology advances, gate structures employing work function materials soon reaches their physical and electrical limitation, causing side-effects including electrical instability and negative bias temperature instability (NBTI) effect.
NBTI effect is typically caused by accumulation of electrical potentials between silicon substrate and silicon oxide layers, which induces an effect when gate electrode is negatively biased. As PMOS transistors apply negative bias to generate electrons on metal gate adjacent to gate oxide, reject electrons on n-type substrate, and generate electron holes on n-type substrate and electron hole channel under gate structure thereby inducing electron holes of the source/drain region to be transmitted through this channel, NBTI effect is especially influential in CMOS devices containing PMOS structures.
SUMMARY OF THE INVENTION
It is therefore an objective of the present invention to provide a method of fabricating semiconductor device for improving issues caused by NBTI in current process.
According to a preferred embodiment of the present invention, a method for fabricating semiconductor device is disclosed. The method includes the steps of: providing a substrate; forming a gate structure on the substrate; forming a lightly doped drain in the substrate; and performing a first implantation process for implanting fluorine ions at a tiled angle into the substrate and part of the gate structure.
According to another aspect of the present invention, a semiconductor device is disclosed. The semiconductor device includes a substrate, a gate structure on the substrate, and a source/drain region in the substrate adjacent to the gate structure. The gate structure includes a first interface layer on the substrate, an interfacial layer on the first interface layer, and a conductive layer on the interfacial layer. Preferably, the first interface layer includes a first region and a second region surrounding the first region, and the concentration of the second region is higher than the concentration of the first region.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-4 illustrate a method for fabricating semiconductor device according to a first embodiment of the present invention.
FIGS. 5-8 illustrate a method for fabricating semiconductor device according to a second embodiment of the present invention.
DETAILED DESCRIPTION
Referring to FIGS. 1-4 , FIGS. 1-4 illustrate a method for fabricating semiconductor device according to a first embodiment of the present invention. As shown in FIG. 1 , a substrate 12 , such as a wafer or silicon-on-insulator (SOI) substrate is provided. A stack structure 14 is then formed on the substrate 12 , in which the stack structure 14 may be fabricated by first forming an interfacial layer 16 on the substrate 12 and then forming a sacrificial layer 18 on the interfacial layer 16 . In this embodiment, the interfacial layer 16 is preferably composed of silicon material such as silicon dioxide (SiO 2 ), silicon nitride (SiN), silicon oxynitride (SiON), or other dielectric material with high permittivity or dielectric constant. The sacrificial layer 18 is preferably composed of single crystal silicon, doped polysilicon, or amorphous polysilicon, but could also be composed material selected from silicides or other metal material.
According to an embodiment of the present invention, a hard mask (not shown) could be selectively formed on the surface of the sacrificial layer 18 after the formation of the sacrificial layer 18 , in which the hard mask could be selected from the group consisting of SiC, SiON, SiN, SiCN and SiBN, but not limited thereto. Since the hard mask is a selectively formed element, it will be omitted in the following embodiment for the sake of brevity.
Next, an implantation process 20 is conducted to implant fluorine ions into an interface between the interfacial layer 16 and the substrate 12 . This forms an interface layer 22 between the substrate 12 and the interfacial layer 16 .
Next, as shown in FIG. 2 , a patterned mask, such as a patterned resist (not shown) is formed on the sacrificial layer 18 , and a pattern transfer process is conducted by using the patterned resist as mask through single or multiple etching processes to remove part of the sacrificial layer, interfacial layer, and interface layer not covered by the patterned resist for forming a gate structure 24 . In other words, the gate structure 24 preferably includes a patterned interfacial layer 16 , a patterned interface layer 22 , and a patterned sacrificial layer 18 .
Next, a1 liner (not shown) could be selectively formed on the sidewall of the gate structure 24 , and a lightly doped implantation process is conducted to form a lightly doped drain 26 in the substrate 12 adjacent to two sides of the liner or the gate structure 24 . Preferably, the dopants implanted during the lightly doped implantation process are adjusted according to the type of transistor being fabricated. For instance, if a NMOS transistor were to be fabricated, n-type dopants are implanted into the substrate 12 whereas if a PMOS transistor were to be fabricated, p-type dopants are implanted into the substrate 12 .
After forming the lightly doped drain 26 , another implantation process 28 is conducted to implant fluorine ions at a tilted angle into the substrate 12 and part of the gate structure 24 . In this embodiment, the concentration of the fluorine ions implanted during the implantation process 28 is substantially the same as the concentration of the fluorine ions implanted during the implantation process 20 , but not limited thereto. For instance, the concentration of the fluorine ions implanted during the implantation process 28 could also be higher or lower than the concentration of fluorine ions implanted during the implantation process 20 depending on the demand of the product, which are all within the scope of the present invention.
It should be noted that since the implantation process 28 is conducted at a tilted angle so that some of the fluorine ions implanted during implantation process 28 would overlap some of the fluorine ions implanted during the previous implantation process 20 , a first region 30 and a second region 32 surrounding the first region 30 are preferably formed in the interface layer 22 between the substrate 12 and the interfacial layer 16 after the implantation process 28 . Moreover, as the second region 32 includes fluorine ions implanted from both implantation processes 20 and 28 while the first region 30 only includes fluorine ions implanted from a single implantation process, the concentration of fluorine ions in the second region 32 is preferably higher than the concentration of fluorine ions in the first region 30 . It should also be noted that even though the first region 30 and the second region 32 appeared to have a rectangular shaped cross-section, the present invention could also adjust the boundary and position of ion implantation to form a substantially triangular cross-section for the second region 32 and a substantially trapezoid cross-section for the first region 30 in the interface layer 22 according to the demand of the product, and in such instance the concentration of fluorine ions in the second region 32 would also be higher than the concentration of fluorine ions in the first region 30 .
Next, as shown in FIG. 3 , a spacer 34 is formed on the sidewall of the gate structure 24 , and a source/drain region 36 is formed in the substrate 12 adjacent to two sides of the spacer 34 . In this embodiment, the formation of the spacer 34 could include formation of an offset spacer and a main spacer, and despite the spacer 34 is formed after the implantation process 28 , an embodiment involving an order of first forming an offset spacer on the sidewall of the gate structure 24 , conducting the implantation process 28 to form the aforementioned first region 30 and second region 32 , and then forming a main spacer on the sidewall of the offset spacer could also be employed according to the demand of the product, which is also within the scope of the present invention. Next, a contact etch stop layer (CESL) 38 is formed on the gate structure 24 , and an interlayer dielectric (ILD) layer 40 is formed on the CESL 38 . It should be noted that elements including epitaxial layer and silicides could also be formed before the deposition of the CESL 38 according to the demand of the product, and as the fabrication of these elements are well known to those skilled in the art, the details of which are not explained herein for the sake of brevity. In addition, if the sacrificial layer 18 in the gate structure 24 were composed of metal material, a fabrication of MOS transistor could be completed at this stage.
Next, a replacement metal gate (RMG) process could be selectively conducted along with a high-k last process to transform the gate structure 24 into a metal gate. As shown in FIG. 4 , the RMG process could be accomplished by first using a planarizing process to partially remove the ILD layer 40 and the CESL 38 to expose the surface of the sacrificial layer 18 of the gate structure 24 , and then performing a selective dry etching or wet etching process, such as using etchants including ammonium hydroxide (NH 4 OH) or tetramethylammonium hydroxide (TMAH) to remove the sacrificial layer 18 from the gate structure 24 for forming a recess (not shown). Next, a U-shaped high-k dielectric layer 50 and a conductive layer 46 including a work function metal layer 42 and low resistance metal layer 44 is deposited into the recess, and another planarizing process is conducted thereafter to form a metal gate 48 .
In this embodiment, the work function metal layer 42 is formed for tuning the work function of the metal gate 48 so that the device could be adapted in an NMOS or a PMOS transistor. For an NMOS transistor, the work function metal layer 42 having a work function ranging between 3.9 eV and 4.3 eV may include titanium aluminide (TiAl), zirconium aluminide (ZrAl), tungsten aluminide (WAl), tantalum aluminide (TaAl), hafnium aluminide (HfAl), or titanium aluminum carbide (TiAlC), but is not limited thereto. For a PMOS transistor, the work function metal layer 42 having a work function ranging between 4.8 eV and 5.2 eV may include titanium nitride (TiN), tantalum nitride (TaN), tantalum carbide (TaC), but is not limited thereto. A barrier layer (not shown) could be formed between the work function metal layer 42 and the low resistance metal layer 44 , in which the material of the barrier layer may include titanium (Ti), titanium nitride (TiN), tantalum (Ta) or tantalum nitride (TaN). Furthermore, the material of the low resistance metal layer 44 may include copper (Cu), aluminum (Al), titanium aluminum (TiAl), cobalt tungsten phosphide (CoWP) or any combination thereof.
According to an embodiment of the present invention, as shown in FIG. 4 , another implantation could be selectively conducted after forming the high-k dielectric layer 50 to implant fluorine ions into an interface between the high-k dielectric layer 50 and interfacial layer 16 for forming another interface layer 52 . After forming the interface layer 52 , the conductive layer 46 containing both the work function metal layer 42 and low resistance metal layer 44 could be formed thereafter.
Referring to FIGS. 5-8 , FIGS. 5-8 illustrate a method for fabricating semiconductor device according to a second embodiment of the present invention. As shown in FIG. 5 , a substrate 62 , such as a wafer or silicon-on-insulator (SOI) substrate is provided. A stack structure 64 is then formed on the substrate 62 , in which the stack structure 64 may be fabricated by sequentially forming an interfacial layer 66 , a high-k dielectric layer 68 , a bottom barrier metal (BBM) layer 70 , and a sacrificial layer 72 on the substrate 62 .
In this embodiment, the interfacial layer 66 is preferably composed of silicon material such as silicon dioxide (SiO 2 ), silicon nitride (SiN), or silicon oxynitride (SiON), or other dielectric material with high permittivity or dielectric constant. The sacrificial layer 72 is preferably composed of single crystal silicon, doped polysilicon, or amorphous polysilicon, but could also be composed material selected from silicides or other metal material.
As the present embodiment is preferably accomplished by the employment of a high-k first process from gate last process, the high-k dielectric layer 68 preferably has a “I-shaped” cross section and preferably be selected from dielectric materials having dielectric constant (k value) larger than 4. For instance, the high-k dielectric layer 68 may be selected from hafnium oxide (HfO 2 ), hafnium silicon oxide (HfSiO 4 ), hafnium silicon oxynitride (HfSiON), aluminum oxide (Al 2 O 3 ), lanthanum oxide (La 2 O 3 ), tantalum oxide (Ta 2 O 5 ), yttrium oxide (Y 2 O 3 ), zirconium oxide (ZrO 2 ), strontium titanate oxide (SrTiO 3 ), zirconium silicon oxide (ZrSiO 4 ), hafnium zirconium oxide (HfZrO 4 ), strontium bismuth tantalate (SrBi 2 Ta 2 O 9 , SBT), lead zirconate titanate (PbZr x Ti 1-x O 3 , PZT), barium strontium titanate (Ba x Sr 1-x TiO 3 , BST) or a combination thereof.
In this embodiment, the high-k dielectric layer 68 may be formed by atomic layer deposition (ALD) process or metal-organic chemical vapor deposition (MOCVD) process, but not limited thereto.
Similar to the first embodiment, a hard mask (not shown) could be selectively formed on the surface of the sacrificial layer 72 after the formation of the sacrificial layer 72 , in which the hard mask could be selected from the group consisting of SiC, SiON, SiN, SiCN and SiBN, but not limited thereto. Since the hard mask is a selectively formed element, it will be omitted in the following embodiment for the sake of brevity.
Next, an implantation process 74 is conducted to implant fluorine ions entirely into the stack structure 64 . This forms a first interface layer 76 between the substrate 62 and the interfacial layer 66 and a second interface layer 78 between the interfacial layer 66 and the high-k dielectric layer 68 .
Next, as shown in FIG. 6 , a patterned mask, such as a patterned resist (not shown) is formed on the sacrificial layer 72 , and a pattern transfer process is conducted by using the patterned resist as mask through single or multiple etching processes to remove part of the sacrificial layer 72 , BBM layer 70 , high-k dielectric layer 68 , second interface layer 78 , interfacial layer 66 , and first interface layer 76 not covered by the patterned resist for forming a gate structure 80 . In other words, the gate structure 80 preferably includes a patterned first interface layer 76 , patterned interfacial layer 66 , patterned second interface layer 78 , patterned high-k dielectric layer 68 , patterned BBM layer 70 , and patterned sacrificial layer 72 .
Next, a1 liner (not shown) could be selectively formed on the sidewall of the gate structure 80 , and a lightly doped implantation process is conducted to forma lightly doped drain 82 in the substrate 62 adjacent to two sides of the liner or the gate structure 80 . Preferably, the dopants implanted during the lightly doped implantation process are adjusted according to the type of transistor being fabricated. For instance, if a NMOS transistor were to be fabricated, n-type dopants are implanted into the substrate 62 whereas if a PMOS transistor were to be fabricated, p-type dopants are implanted into the substrate 62 .
After forming the lightly doped drain 82 , another implantation process 84 is conducted to implant fluorine ions at a tilted angle into the substrate 62 and part of the gate structure 80 . Similar to the first embodiment, the concentration of the fluorine ions implanted during the implantation process 84 is substantially the same as the concentration of the fluorine ions implanted during the implantation process 74 , but not limited thereto. For instance, the concentration of the fluorine ions implanted during the implantation process 84 could also be higher or lower than the concentration of fluorine ions implanted during the implantation process 74 depending on the demand of the product, which are all within the scope of the present invention.
It should be noted that since the implantation process 84 is conducted at a tilted angle so that some of the fluorine ions implanted during implantation process 84 would overlap some of the fluorine ions implanted during the previous implantation process 74 , a first region 86 and a second region 88 surrounding the first region 86 are preferably formed in the first interface layer 76 between the substrate 62 and the interfacial layer 66 and the second interface layer 78 between the interfacial layer 66 and the high-k dielectric layer 68 . Moreover, as the second region 88 includes fluorine ions implanted from both implantation processes 74 and 84 while the first region 86 only includes fluorine ions implanted from the first implantation process 74 , the concentration of fluorine ions in the second region 88 is preferably higher than the concentration of fluorine ions in the first region 86 . It should also be noted that even though the first region 86 and the second region 88 appeared to have a rectangular shaped cross-section, the present invention could also adjust the boundary and position of ion implantation to form a substantially triangular cross-section for the second region 88 and a substantially trapezoid cross-section for the first region 86 in the first interface layer 76 and second interface layer 78 according to the demand of the product, and in such instance the concentration of fluorine ions in the second region 88 would also be higher than the concentration of fluorine ions in the first region 86 .
Next, as shown in FIG. 7 , a spacer 90 is formed on the sidewall of the gate structure 80 , and a source/drain region 92 is formed in the substrate 62 adjacent to two sides of the spacer 90 . Similar to the first embodiment, the formation of the spacer 90 could include formation of an offset spacer and a main spacer, and despite the spacer is formed after the implantation process 84 , an embodiment involving an order of first forming an offset spacer on the sidewall of the gate structure 80 , conducting the implantation process 84 to form the aforementioned first region 86 and second region 88 , and then forming a main spacer on the sidewall of the offset spacer could also be employed according to the demand of the product, which is also within the scope of the present invention. Next, a contact etch stop layer (CESL) 94 is formed on the gate structure 80 , and an interlayer dielectric (ILD) layer 96 is formed on the CESL 94 . It should be noted that elements including epitaxial layer and silicides could also be formed before the deposition of the CESL 94 according to the demand of the product, and as the fabrication of these elements are well known to those skilled in the art, the details of which are not explained herein for the sake of brevity.
Next, a replacement metal gate (RMG) process could be conducted to transform the gate structure 80 into a metal gate. As shown in FIG. 8 , the RMG process could be accomplished by performing a selective dry etching or wet etching process, such as using etchants including ammonium hydroxide (NH 4 OH) or tetramethylammonium hydroxide (TMAH) to remove the sacrificial layer 72 from the gate structure 80 for forming a recess (not shown). Next, a conductive layer 102 including a U-shaped work function metal layer 98 and low resistance metal layer 100 is deposited into the recess, and another planarizing process is conducted thereafter to form a metal gate 104 .
In this embodiment, the work function metal layer 98 is formed for tuning the work function of the metal gate 104 so that the device could be adapted in an NMOS or a PMOS transistor. For an NMOS transistor, the work function metal layer 98 having a work function ranging between 3.9 eV and 4.3 eV may include titanium aluminide (TiAl), zirconium aluminide (ZrAl), tungsten aluminide (WAl), tantalum aluminide (TaAl), hafnium aluminide (HfAl), or titanium aluminum carbide (TiAlC), but is not limited thereto. For a PMOS transistor, the work function metal layer 98 having a work function ranging between 4.8 eV and 5.2 eV may include titanium nitride (TiN), tantalum nitride (TaN), tantalum carbide (TaC), but is not limited thereto. A barrier layer (not shown) could be formed between the work function metal layer 98 and the low resistance metal layer 100 , in which the material of the barrier layer may include titanium (Ti), titanium nitride (TiN), tantalum (Ta) or tantalum nitride (TaN). Furthermore, the material of the low resistance metal layer 100 may include copper (Cu), aluminum (Al), tungsten (W), titanium aluminum (TiAl), cobalt tungsten phosphide (CoWP) or any combination thereof.
Overall, the present invention preferably conducts two ion implantation processes to inject fluorine ions into a gate structure before and after forming the gate structure on a substrate. The first implantation process is preferably conducted to implant fluorine ions into the stack structure entirely before forming the gate structure whereas the second implantation process is conducted to implant fluorine ions at a tilted angle into the gate structure after the gate structure is formed. Preferably, the two implantation processes are carried out to form a first region and a second region surrounding the first region in a first interface layer between substrate and interfacial layer and a second interface layer between interfacial layer and high-k dielectric layer, in which the concentration of the fluorine ions in the second region is substantially higher than the concentration of fluorine ions in the first region.
Typically, the bond strength of Si—O bond and Si—H bond between material layers such as substrate, interfacial layer, and high-k dielectric layer is around 3.18 eV (taking Si—H bond as an example) or 4.8 eV (taking Si—O bond as an example). A weak bond strength created under these circumstances induces NBTI effect easily, which further affects the performance of the device substantially. By injecting fluorine ions into the interface layer to form Si—F bonds through aforementioned implant processes, the present invention is able to utilize the Si—F bond created to boost up the bond strength between material layers to about 5.73 eV, thereby increasing stability between the material layers and ultimately improving side effects caused by NBTI.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
|
A method for fabricating semiconductor device is disclosed. The method includes the steps of: providing a substrate; forming a gate structure on the substrate; forming a lightly doped drain in the substrate; and performing a first implantation process for implanting fluorine ions at a tiled angle into the substrate and part of the gate structure.
| 7
|
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to a novel system of paint application for use both indoors and outdoors.
BACKGROUND
[0002] Paints and other types of coating materials have long been used to protect surfaces and for decorative purposes. Solvent based materials have been widely used in the past because of their durability and fast drying properties. They have over the years fallen into disfavour for interior uses because of their release of environmentally dangerous and polluting organic solvents into the atmosphere. More recently on the scene are waterborne decorative coatings which have received great applause because of their environmental friendliness. In certain jurisdictions the use of waterborne products is now mandatory for interior use as is currently the case in The Netherlands and other European countries.
[0003] Even though significant improvements have been made to waterborne paints over the years, nevertheless the application of waterborne paints is still far from perfect. For instance, especially for decorative purposes (i.e. painting interiors within the home), waterborne paints are typically applied by using traditional paint brush and roller techniques. Not only is this application method extremely time consuming, but it can be more expensive since there is often a requirement for a minimum of two (2) if not multiple layers or coatings of paint to be applied in order to achieve the desired aesthetic effect on the surface or substrate.
[0004] In applying paint, typical industry standards (and for that matter standards demanded by consumers or professional painters/decorators) are that the paint applied (whether waterborne or solvent based) to the desired surface or substrate should be of a sufficient durability and meet a minimum level of aesthetic performance in the areas of smooth coating surface (i.e. application results in a level coating surface); avoiding sagging (i.e. downward movement of the paint film between the time of application and setting resulting in an uneven surface) often caused by the paint drying too slowly or the paint being of too low viscosity or the paint film being applied in too thick a fashion. This latter performance criteria is often an issue when using standard brushing or rolling techniques. There is also a requirement that any paint applied should have a proper level of opacity caused by sufficient layer-thickness of paint. It is also highly desirable for the paint application to have a level of “cleanliness” (i.e. avoiding fouling of adjacent objects or surfaces typically accomplished through use of precise paint brush application or pre-masking for spray application of the paint).
[0005] In addition to the aesthetic requirements demanded by consumers and professional decorators there exists the need for the paint to be applied in a cost-effective and less time-consuming fashion. One of the complicating factors of the equation is that there are fewer and fewer skilled craftsmen in the painting industry and therefore the need for reducing time spent on each project as well as increasing the intervals between repainting requirements is becoming ever more critical in this industry sector.
[0006] To assist craftsmen there have been developed various means of spray painting using a gun-type apparatus. Both waterborne and solvent-based paints may be applied to a surface by atomisation in a spray gun using, for example, a high pressure medium such as compressed air often with mixed results. For traditional or standard brushing or rolling techniques it is often possible to apply a single relatively thick coating of paint of up to 200 microns but if this was attempted using a spraying technique with waterborne paints this could result in a problem. This is due to the fact that standard waterborne paints are often very slow to dry and can result in sagging on the finished surface or substrate. This problem is often worsened since standard paints are typically thinned down in order to be spray applied. As a result of these concerns, waterborne paints are rarely used in conjunction with spray painting. Unfortunately, waterborne paints are therefore still typically applied by brush or through use of a roller resulting in only average aesthetic results (these paints are more sensitive to brush marks and layer-thickness variations) and the expenditure of a great amount of time with the painting activity itself. Even though using of spray application techniques results in a larger area of coated surface in less amount of time than manual brush and roller applications, any economy with time is typically lost with the painstaking requirements for masking and covering any surfaces or substrates that are not desired to be coated.
[0007] The use of spray guns also creates its own series of environmental and economical concerns since it is highly desirable that any over-spray of paint and bounce-back be limited to a minimum. Another form of spraying is the so-called HVLP (High Volume-Low Pressure). HVLP provides spray efficiency (or transfer efficiency) to substrate of between 65% and 90%, whereas conventional high-pressure spray guns typically only achieve a transfer efficiency of between 25% to 30%. HVLP though typically only works using lower viscosity/higher solvent products—thus again rules out using standard waterborne paints with HVLP as these paints are quite viscous in nature. Additionally, the application of thick paint layers of up to 200 microns are desirable for reasons of both durability and aesthetics (as well as being desirable for economic and time-saving reasons) are not possible with HVLP. Use of HVLP at present is not recommended with current waterborne products (e.g. waterborne lacquered products) because the end results is often sagging and lacks the desired smoothness. Further drawbacks with standard HVLP equipment is resulting amount of over-spray which can be considerable and limited layer-thickness build up. This would present obvious problems when a user is required to paint a large substrate area
[0008] Currently available products and apparatuses are clearly unable to provide what craftsmen in the highly competitive decorative market truly require: rapid coverage of a desired surface or substrate through use of a spraying apparatus that accommodates waterborne products resulting in a surface painted to high aesthetic standards (even beyond those aesthetic standards more readily acquired through using traditional brushing and rolling techniques) with little over-spray. Such a comprehensive system does not exist at present.
SUMMARY OF THE INVENTION
[0009] The present invention resolves this long-felt problem through use of a combination of novel solutions to the specific problems identified above currently facing the paint and decorating industry. The present invention combines the use of a novel waterborne paint which may then be applied using a novel spraying apparatus resulting in a fast and efficient process as well as being aesthetically pleasing for painting large or small surface areas.
[0010] The first aspect of the invention is the development of a novel spray paint apparatus incorporating many of the desirable features of a traditional HVLP apparatus, but further including a membrane pump to allow for the handling of higher viscosity paint to facilitate high layer-thickness applications (typically in a single application) with a marked reduction in over-spray. The apparatus of the present invention functions by using heated air, and comprises a paint and paint transportation system to allow the handling of higher viscous paints and resulting in good levelling, rapid drying and a good build up in the layer of the applied paint to the surface or substrate. This system incorporates a heat exchanger utilising the hot air generated through use of the engine motor of the spraying apparatus. The hot air is fed along or passed over a coil, the coil forming a conduit for the paint. The heating of the paint provides for better levelling, drying and application of the desired paint product.
[0011] A further aspect of the present invention, is an improved waterborne paint with a viscosity profile tailored for use with the novel spraying apparatus of the present invention. This novel product though is not limited for use solely with the apparatus described in this invention. The novel paint of the present invention results in the desired characteristics of being faster drying, minimal sagging, good levelling and maintains all the technical and environmental advantages of standard waterborne paint and decorating products.
[0012] An additional aspect of the present invention comprises the combination of the above-mentioned aspects resulting in a unique and highly effective complete painting system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The following description and the accompanying drawings referred to therein are included by way of non-limiting embodiments.
[0014] FIG. 1 illustrates a paint spraying apparatus of the present invention.
[0015] FIG. 2 illustrates an axial section through the heat exchanger for use with the apparatus of the present invention
[0016] FIG. 3 illustrates a mobile trolley unit incorporating the paint apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] In order to overcome the aesthetic problems in using waterborne products with spraying apparatus, it has been found that pre-heating the paint material before application or atomisation results in a more uniform finish and levelling and allows a thicker coat of the paint material to be applied.
[0018] The apparatus of the present invention is the subject of a separate priority application filed 19 Dec. 2001 at the United Kingdom Patent Office being assigned application no. 0130320.5, and also of a separate priority application filed 28 Feb. 2002 at the United Kingdom Patent Office being assigned application no. 0204727.2. These applications and all features described therein are hereby incorporated by reference into the present application.
[0019] In a first embodiment of the present invention the paint material is pre-heated by means of an indirect heat exchanger. The heating medium is typically air, although not necessarily confined to this medium. After passing through the heat exchanger the heating medium is preferably supplied to the spray gun for use in atomising the preheated material. Since the heating medium thus supplies additional heat to the region of application, the quality of the coating is improved and the energy efficiency of the apparatus is increased.
[0020] The heating medium may be warmed using various methods before reaching the heat exchanger, for example by using an electrical heating element. However, it is preferred to heat the medium by passing it through a turbine. This has the advantage that it produces large volumes of heated air at a low pressure compared with a standard air compressor, thus reducing the effects of over-spray and bounce back when applying the paint material.
[0021] The indirect heat exchanger preferably has a housing which defines a vortex chamber through which the heating medium passes and the atomisable material passes through a heat-exchange conduit disposed within the chamber. The vortex chamber is preferably of a general cylindrical shape and can have concave ends. This however is certainly not mandatory and a person skilled in the art would be able to alter the overall shape or configuration without having an input on the efficiency of the vortex chamber. Specifically, the shape of the chamber creates a vortex in order that the warmed air can freely circulate around the chamber a number of times before leaving the chamber. The heat-exchange conduit is preferably coiled within the vortex chamber.
[0022] Referring to FIG. 1 , paint is drawn from a reservoir ( 1 ) which can be a paint can or trough through a flexible tube ( 2 ) by means of a suitable electrically or pneumatically operated pumping mechanism ( 3 ), for example a diaphragm pump. The pump feeds the paint via a pipe ( 4 ) to be heated by passing through the secondary of an indirect heat exchanger ( 5 ). After departing from the heat exchanger the paint travels along and through a flexible hose ( 6 ) to a spray gun and nozzle ( 7 ). The length of the flexible conduit such as a hose or tube ( 6 ) may be varied in order to provide the user of the spraying apparatus a suitable length of flexible hose so as not to interfere or inhibit the mobility of the user or the apparatus. The diaphragm pump may also contain a pulsation damper and filter unit.
[0023] Atmospheric air is drawn through an inlet ( 10 ) into a turbine ( 11 ) which is driven at high speed by an electric or pneumatic motor ( 12 ), typically operating at about 22,000 rpm. The turbine for instance can be a simple brush electric motor. On passage through the turbine the air is warmed typically to the order of 20° C. above ambient temperature by generating friction and compression producing a large volume of warmed air at a relatively low pressure. The level of rise above ambient temperature can be dependent on the paint material being applied and therefore should be of a sufficient amount to allow a uniform finish and levelling and a thicker coat of the paint material to be applied to the substrate. This warmed air passes through a pipe ( 13 ) to the heat exchanger ( 5 ) where the air gives up a proportion of its heat to the paint passing through the secondary of the heat exchanger. Exhaust air from the heat exchanger passes along a separate duct of the hose ( 6 ) to the spray gun and nozzle ( 7 ), where the air flow is used to atomise the warm paint into a fine spray of droplets interspersed with the warm air flow.
[0024] FIG. 2 illustrates a heat exchanger of the present invention. The heat exchanger has a housing ( 20 ) formed by two concave spun parts ( 21 and 22 ) providing a cylindrical side wall ( 23 ) with concave end walls ( 24 and 25 ). Warmed air from the turbine enters the chamber ( 26 ) formed within the housing through an off-centre inlet connection ( 27 ) in one of the end walls ( 25 ) and leaves through a similar off-centre outlet connection ( 28 ) in the other end wall ( 24 ). The elongated-spherical shape of the housing creates a vortex within the housing so that the air circulates around the chamber a number of times before leaving the chamber. The secondary of the heat exchanger forms a stainless steel tube ( 29 ) which is coiled into a cylindrical shape and supported co-axially within the housing ( 20 ) by means of threaded ends. It should be appreciated by one skilled in the art that use of materials other than stainless steel for the tube ( 29 ) would be acceptable.
[0025] The spraying apparatus can also be housed in a cart for ease of mobility as illustrated in FIG. 3 .
[0026] Although the apparatus of the present invention has been developed based on certain principles of standard HVLP machinery, a similar design based on Low Volume Low Pressure (LVLP) would also be acceptable.
[0027] The second aspect of the present invention is the provision of a novel sprayable coating (paint) material. The paint material although designed for use in conjunction with the above-described spraying apparatus and is waterborne in basis, is also suitable for use with other spraying mechanisms or apparatus or use by a conventional compressed (high pressure) air system or LVLP system so long as the claimed paint is pre-heated before application or atomisation.
[0028] One of the advantages of the specially developed paint material of the present invention is that when used by a spraying apparatus, and in particular the novel paint apparatus of the present invention the wet film thickness reaches a typically uniform level of approximately 200 microns compared to the previous wet film thickness found in using conventional satin paint products of approximately 100 microns. The wet film thickness of standard satin paint products can be as low as 40 microns to 50 microns when sprayed, which can result in a requirement for additional layers (upwards to an extra 2 coats of paint material) being applied. This is not advantageous or cost effective for decorative or industry-related purposes. The applicant has identified certain important criteria or parameters that optimise the sprayable nature of waterborne paint materials on substrates. By identifying these parameters which have never before been identified, the invention therefore supplies a paint requiring only a single application (by use of a spraying apparatus) of waterborne paint material is required and the aesthetic results are far superior to those experienced with standard waterborne paint products.
[0029] The paint of the present invention is a modified waterborne paint and must meet three criteria. The sprayable paint must possess low shear viscosity, sag resistance and satisfactory wet film thickness after spraying. For instance, the shear viscosity can be measured using a HAAKE VT181 viscosimeter using a cylindrically shaped spindle.
[0030] It was determined that a suitable viscosity at a rotation speed of 181 rpm is approximately 5-30 dPa·s, preferably at approximately 10-25 dPa·s under conditions of 23° C. and 50% RH. A particularly preferred viscosity is in the region of approximately 15-22 dPa·s and an optimal viscosity for the higher shear at approximately 17-20 dPa·s. A low shear viscosity is assessed at a speed of 5.6 rpm is approximately 50-250 dPa·s, or preferably at approximately 80-200 dPa·s or more preferably at approximately 110-170 dPa·s with an optimal low shear viscosity of around 130-150 dPa·s.
[0031] Resistance to sagging is determined for instance using a multinotch applicator such as an ASTM D 4400 and can be analysed on an index basis. The inventors have discovered that waterborne paint suitable for spraying, particularly with the apparatus described in the present invention, should have an anti-sag index rating of between approximately 500 μm to 1100 μm, and preferably, between approximately 700 μm to approximately 800 μm.
[0032] Finally, wet film thickness after spray application of the paint should range from approximately 200 μm to approximately 700 μm. The wet film thickness can be determined, for instance, by measurements from an ASTM D machine.
[0033] Particularly preferred waterborne paints of the present invention are polyurethane modified acrylics.
[0034] As a final aspect of the present invention is the use of the novel spray painting apparatus in combination or interlinked with the novel sprayable coating material. An integrated system is a highly unique concept in the painting and decorating industry which has typically developed through the generation of so-called stand alone products or features rather than the development of integrated systems. The advantages of the claimed combination invention are in the savings in labour time and costs, limited over-spray of the paint, consistent results, and high levels of layer-thickness per application of paint thus resulting in a single application of the novel paint. The overall result of fusing the spraying apparatus and the waterborne paint of the present invention is that excellent aesthetic and technical improvements are achieved even above that observed using traditional brush and roller techniques and is delivered at a lower cost.
[0035] It will be appreciated that the features disclosed herein may be present in any feasible combination. Whilst the above description sets out the emphasis on those areas which, in combination, are believed to be new and inventive, protection is claimed for any inventive combination of the features disclosed herein.
|
This invention describes the development of a novel spray paint High Volume Low Pressure (HVLP) apparatus including a membrane pump to allow for the handling of higher viscosity paint to facilitate high layer-thickness applications (typically in a single paint application) with a marked reduction in over-spray. The apparatus functions by using heated air and allows for heating of waterborne paints and in particular a novel waterborne paint also the subject of this application. This waterborne paint provides for better levelling, drawing and application of the paint product to a desired substrate. The paint product claimed in the invention has a product to a desired substrate. The paint product claimed in the invention has a viscosity profile tailored for use with the spraying apparatus of the present invention. A further aspect of the present invention comprises the combination of the painting apparatus and the sprayable paint product as an effective integrated painting system.
| 1
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to shoes and, more specifically, to shoes having replaceable decorative members whereby the style of the shoe can be changed as desired by the user.
[0003] The present invention is a shoe having multiple changeable top, side and rear decorative covers providing for changing the style and appearance of a shoe, whereby a user can selectively replace the top, side or rear cover from a plurality of top, side or rear covers.
[0004] The shoe and top cover have attachment means for releasably fixing said top, side and rear cover to said shoe. The removable top, side and rear can be swapped with different colors and textures to create interesting new looks using the same base shoe.
[0005] The present invention further provides that the shoe can have an open toe top with a plurality of top covers providing means for changing the shoe appearance using any appropriate fastener taken from the group of hook and loop, snap, hook, zipper or magnet for attaching the top cover or overlays to the shoe.
[0006] 2. Description of the Prior Art
[0007] There are other shoes designed with replaceable elements. While these shoes may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention, as hereinafter described.
SUMMARY OF THE PRESENT INVENTION
[0008] A primary object of the present invention is to provide shoes having a plurality of replaceable covers and overlays whereby the appearance and style of the shoe can be selectively changed at the user's discretion.
[0009] Another object of the present invention is to provide shoes having covers and overlays with one of a mating fastener incorporated thereon.
[0010] Still yet another object of the present invention is to provide toe-covers for a toe cover aperture having a corresponding fastener member forming an integral part therewith whereby the toe cover can be releasably attached to a toe cover aperture.
[0011] Another object of the present invention is to provide a shoe having a plurality of overlays and toe covers with fasteners taken from the group of hook and loop, zippers, snaps, hooks and magnets.
[0012] Yet another object of the present invention is to provide shoe toe covers whereby the appearance of the shoe can be changed by replacing the toe cover from a plurality of toe cover appliques.
[0013] Additional objects of the present invention will appear as the description proceeds.
[0014] The present invention overcomes the shortcomings of the prior art by providing shoes having sectional overlays and toe covers whereby the style of the shoe can be changed as desired by the user. The shoe sectional overlays and toe covers have corresponding fasteners for releasably fixing the overlays and toe cover appliques to the shoe whereby at least one of the shoe sectional overlays and/or toe covers can be swapped with different colors and textures to create interesting new looks using the same base shoe.
[0015] The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawings, which forms a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawings, like reference characters designate the same or similar parts throughout the several views.
[0016] The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0017] In order that the invention may be more fully understood, it will now be described, by way of example, with reference to the accompanying drawing in which:
[0018] FIG. 1 is an illustrative view of the present invention in use.
[0019] FIG. 2 is an illustrative view of the present invention in use.
[0020] FIG. 3 is a perspective view of the present invention.
[0021] FIG. 3A is a perspective view of the present invention.
[0022] FIG. 3B is a perspective view of the present invention.
[0023] FIG. 3C is a perspective view of the present invention.
[0024] FIG. 4 is an exploded view of the present invention.
[0025] FIG. 4A is an exploded view of the present invention.
[0026] FIG. 4B is an exploded view of the present invention.
[0027] FIG. 4C is an exploded view of the present invention.
[0028] FIG. 5 is a detailed view of the present invention.
[0029] FIG. 6 is a perspective view of the present invention.
[0030] FIG. 7 is a detailed view of the present invention.
[0031] FIG. 8 is an exploded view of the present invention.
[0032] FIG. 9 is a detailed view of the present invention.
[0033] FIG. 10 is an exploded view of the present invention. Shown is the present invention,
[0034] FIG. 11 is a side view of the present invention having magnetic therapy for feet.
[0035] FIG. 12A is an illustrative view of another element of the present invention in use.
[0036] FIG. 12B is an illustrative view of another element of the present invention in use.
DESCRIPTION OF THE REFERENCED NUMERALS
[0037] Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, the figures illustrate the Shoes with Interchangeable Appliques of the present invention. With regard to the reference numerals used, the following numbering is used throughout the various drawing figures.
[0038] 10 Shoes with Interchangeable Appliqués of the present invention
[0039] 11 interchangeable cover
[0040] 12 shoe
[0041] 13 top aperture
[0042] 14 top cover
[0043] 16 sidecover
[0044] 18 rear cover
[0045] 20 user
[0046] 22 storage box
[0047] 24 snap fastener
[0048] 26 magnetic fastener
[0049] 28 zipper fastener
[0050] 30 hook and loop fastener
[0051] 32 style “A”
[0052] 34 style “B”
[0053] 36 style “C”
[0054] 38 style “D”
[0055] 40 style “E”
[0056] 42 fastener element
[0057] 44 decorative design
[0058] 46 therapeutic magnet
[0059] 48 magnetic foot therapy
[0060] 50 peep toe shoe
[0061] 52 peep toe tip
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0062] The following discussion describes in detail one embodiment of the invention (and several variations of that embodiment). This discussion should not be construed, however, as limiting the invention to those particular embodiments, practitioners skilled in the art will recognize numerous other embodiments as well. For definition of the complete scope of the invention, the reader is directed to appended claims.
[0063] FIG. 1 is an illustrative view of the present invention 10 in use. The present invention 10 is a shoe 12 having multiple changeable top 14 , side 16 and rear 18 decorative covers providing for changing the style and appearance of a shoe 12 whereby a user 20 can selectively replace the top 14 , side 16 and rear 18 cover from a plurality of covers 11 stored in a storage box 22 . The shoe 12 and covers 11 having attachment means for releasably fixing to said shoe 12 . The removable decorative covers 11 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0064] FIG. 2 is an illustrative view of the present invention 10 in use. Shown is the present invention 10 with high heel style shoe 12 . The removable covers 11 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 . The fasteners can be snaps 24 , magnetic 26 , zippers 28 or hook and loop elements 30 .
[0065] FIG. 3 is a perspective view of the present invention 10 . Shown is the shoe 12 having top covers 14 with choices of style “A” 32 , style “B” 34 , style “C” 36 , style “D” 38 and style “E” 40 .
[0066] FIG. 3A is a perspective view of the present invention 10 taken from FIG. 3 as illustrated. The present invention 10 is a shoe 12 having multiple changeable side decorative covers 16 providing for changing the style and appearance of a shoe, whereby a user can selectively replace the side cover 16 from a plurality of side covers 16 . Shown is a side cover 16 being secured to the shoe 12 with hook and loop fasteners 30 . Other fastener elements 42 that may be employed are snaps 24 , magnets 26 and zippers 28 .
[0067] FIG. 3B is a perspective view of the present invention 10 taken from FIG. 3 as illustrated. The present invention 10 is a shoe 12 having multiple changeable side decorative covers 16 providing for changing the style and appearance of a shoe, whereby a user can selectively replace the side cover 16 from a plurality of side covers 16 . Shown is a side cover 16 being secured to the shoe 12 with hook and loop fasteners 30 . Other fastener elements 42 that may be employed are snaps 24 , magnets 26 and zippers 28 .
[0068] FIG. 3C is a perspective view of the present invention 10 taken from FIG. 3 as illustrated. The present invention 10 is a shoe 12 having multiple changeable rear decorative covers 18 providing for changing the style and appearance of a shoe, whereby a user can selectively replace the rear cover 18 from a plurality of rear covers 18 . Shown is a rear cover 18 being secured to the shoe 12 with hook and loop fasteners 30 . Other fastener elements 42 that may be employed are snaps 24 , magnets 26 and zippers 28 .
[0069] FIG. 4 is an exploded view of the present invention comprising a shoe 12 having top aperture 13 with multiple changeable top decorative covers 14 providing for changing the style and appearance of a shoe, whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . As illustrated, shoe 12 has a body portion with top aperture 13 having circumferential fastening elements whereby top cover 14 having mating fastening elements covers top aperture 13 . Depicted is top cover 14 fastenable to shoe 12 by means of snap fasteners 24 with other fastening elements 42 that can alternately be employed as fastening elements including hook and loop fasteners 30 and zippers 28 . The removable top can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0070] FIG. 4A is an exploded view of the present invention 10 . Shown is the shoe 12 having a plurality of side covers 16 having different decorative designs 44 including style “1” 46 , style “2” 48 , style “3” 50 and style “4” 52 .
[0071] FIG. 4B is an exploded view of the present invention 10 . Shown is the shoe 12 having a plurality of side covers 16 having different decorative designs 44 including style “1” 46 , style “2” 48 , style “3” 50 and style “4” 52 . The removable side 16 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0072] FIG. 4C is an exploded view of the present invention 10 . Shown is the shoe 12 having a plurality of rear covers 18 having different decorative designs 44 including style “1” 46 , style “2” 48 , style “3” 50 and style “4” 52 . The removable rear cover 18 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0073] FIG. 5 is a detailed view of the present invention 10 . Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating snap attachment means 24 for releasably fixing said top cover 14 to said shoe 12 . The removable top 14 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0074] FIG. 6 is a perspective view of the present invention 10 . Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating hook and loop fastener means 30 for releasably fixing said top cover 14 to said shoe 12 . The removable top 14 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0075] FIG. 7 is a detailed view of the present invention 10 . Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating hook and loop fastener means 30 for releasably fixing said top cover 14 to said shoe 12 . The removable top 14 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0076] FIG. 8 is an exploded view of the present invention 10 . Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating zipper means 28 for releasably fixing said top cover 14 to said shoe 12 . The removable top 14 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0077] FIG. 9 is a detailed view of the present invention 10 . Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating zipper means 28 for releasably fixing said top cover 14 to said shoe 12 . The removable top 14 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0078] FIG. 10 is an exploded view of the present invention 10 . Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating magnetic means 26 for releasably fixing said top cover 14 to said shoe 12 . The removable top 14 can be swapped with different colors and textures to create interesting new looks using the same base shoe 12 .
[0079] FIG. 11 is a side view of the present invention 10 having magnetic therapy for feet. Shown is the present invention 10 , whereby a user can selectively replace the top cover 14 from a plurality of top covers 14 . The shoe 12 and top cover 14 having mating snap means 24 for releasably fixing said top cover 14 to said shoe 12 . Interiorly positioned therapeutic magnets 46 may also be provided to present magnetic therapy 48 to the foot.
[0080] FIG. 12 is an illustrative view of another element of the present invention 10 in use. Shown is a removable peep toe shoe 50 with high heel style shoe and provided in other style shoes. The removable peep toe tip 52 can be swapped with different colors and textures to create interesting new looks using the same base shoe or left off the shoe, allowing the toes to be open and visible.
[0081] FIG. 12A is an illustrative view of another element of the present invention 10 in use. Shown is a removable peep toe shoe 50 with high heel style shoe and provided in other style shoes. The removable peep toe tip 52 can be secured using any of suitable fastener element 42 .
[0082] FIG. 12B is an illustrative view of another element of the present invention 10 in use. Shown is a removable peep toe shoe 50 with high heel style shoe and provided in other style shoes. The removable toe tip 52 can be swapped with different colors and textures to create interesting new looks using the same base shoe or left off the shoe, allowing the toes to be open and visible.
[0083] It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.
[0084] While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.
[0085] Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
|
Shoes having replaceable decorative cover members whereby the style of the shoe can be changed as desired by the user. The shoe and top, side and rear covers have corresponding fasteners for releasably fixing the top cover applique to the shoe whereby the removable top can be swapped with different colors and textures to create interesting new looks using the same base shoe. Integral interior magnets also apply magnetic therapy to the foot within each shoe.
| 0
|
The invention herein described was made in the course of or under a contract or subcontract thereunder with the Department of Defense, Department of the Navy, Naval Sea Systems Command.
BACKGROUND OF THE INVENTION
The present invention relates to a method of welding and more particularly to a method of forming a fillet welded joint between two aluminum members from a single side of the joint.
Normally when welding two contacting metal members which are positioned approximately at right angles to each other, a fillet weld is applied along both sides of the joint. However in some structural applications in which a fillet welded joint is desired, there is ready access to only one side of the joint.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide a novel welding method capable of producing a fillet welded joint between two metal members operating from a single side of the joint. Another object of the present invention is to provide a single-sided fillet weld of good strength characteristics which can be inspected from the backside of the joint.
These as well as other objects, which will become apparent in the discussion which follows, are achieved, according to the present invention, by providing a welding method for forming a fillet welded joint including the steps of placing an abutting edge of a first metal member onto the surface of a second metal member at generally right angles thereto, the abutting edge having a series of alternating lands and slots extending through the entire thickness of the first member, and arc welding employing a consumable electrode to form a fully penetrated fillet weld from one side only of the joint with the weld filling the slots and melting the lands.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of two abutting metal members at right angles to each other prior to forming the fillet weld.
FIG. 2 is a perspective view taken of the members of FIG. 1 after the fillet weld has been formed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, there is illustrated two aluminum members 12, 14 disposed at right angles to each other with the vertical member 12 having an abutting edge resting on the upper surface of the horizontal member 14. The abutting edge of the vertical member 12 is comprised by a series of alternating lands 16 and slots 18. The lands contact the surface of the horizontal member 14 and slots 18 constitute cut out portions extending through the entire thickness of the member 12 so that in these regions there are gaps between the two members. The slots 18 may be formed by machining or punching techniques carried out beforehand.
The joint between members 12 and 14 is welded from a single side of the joint using a high heat input, high speed welding technology known as gas metal-arc (MIG) welding which employs a consumable aluminum electrode and an inert gas atmosphere. By this technique there is obtained a single fillet weld which penetrates through the thickness of the vertical member 12 even in the regions of the narrow lands 16 which melt during the welding.
The width of the lands 16 and the height and width of the slots 18 are significant parameters to the successful practice of the present method. The lands 16 which are necessary to assure that the desired spacing between the two sheets in the regions of gaps 18 would be maintained during welding, must be sufficiently narrow that they will melt readily in the welding arc and will provide little interference and restriction to weld penetration so that penetration of the weld through the entire member 12 may be obtained. Both the height and width of the slot 18 should be closely controlled to obtain the desired weld penetration. If the lengths of the slots are too large, there can be a problem of deflection of the horizontal member 14 up into the slots. Too small a height of the slots will undesirably impede the flow and penetration of the weld metal. It has been found that the height of the slot must be held to a maximum of about 0.040 inches for a 1/8-inch thick vertical aluminum member in order to prevent burn through to the other side of the joint. A land length to slot length ratio in the range of about 1:20 to 1:1 has been found suitable. By way of example, it has been found that when employing a 1/8 inch thick vertical member 12, and with the welding parameters designed to produce a 1/8 inch fillet weld, good results have been obtained when the lands 16 are 1/4 inch long and the slots 18 are 11/8 inch long and 0.040 inches in height. Employing members with these dimensions completely penetrated single-pass fillet welds have been obtained.
The techniques of gas metal-arc (MIG) welding are known in the art. For aluminum, this process employs a consumable, bare aluminum electrode in an inert gas atmosphere. The inert gas atmosphere may be helium, argon or a mixture of the two. No flux is required and thus post-cleaning costs and difficulties are avoided. Gas metal-arc (MIG) welding concentrates the heat more than most other welding methods.
Gas metal-arc (MIG) welding is further described in the literature, for example, in "Welding Alcoa Aluminum", Chapter 4, 1972, Aluminum Company of America, and in U.S. Pat. No. 3,944,781 issued Mar. 16, 1976 to Urbanic et al.
Among the advantages of the invention are that by this method a completely penetrated single-pass fillet weld may be obtained when welding from one side of the joint, the single welding arc is controlled by one operator resulting in savings as compared to a typical double fillet weld technique, the single-sided fillet weld may be visually inspected from the back side of the weld joint permitting good quality control and assurance of adequate penetration, there is reduced filler metal consumption and expense, and there is reduction in transverse and longitudinal distortion as a result of a reduction in total weld solidification shrinkage. Furthermore, an improvement in fatique strength can be realized when compared to conventional single-side fillet welds.
FIG. 2 which is a perspective view of the welded joint shows that the weld 20 has completely penetrated through member 12.
The invention will be further illustrated by the following examples:
EXAMPLE 1
A vertical aluminum sheet 1/8 inch thick (by 2 inches by 3 inches) was treated at the abutting edge to obtain slots 1 inch in length and 0.040 inches in height. The slots were separated from each other by lands 1 inch long. This abutting edge was placed onto a horizontal aluminum sheet of 3/16 inch thickness. Both of these members were made of aluminum alloy 5456. A single sided fillet weld was produced using gas metal-arc (MIG) welding. The power source was a Tek-Tran variable slope 1,000 ampere DC power supply welding machine. The slope of the characteristic ampere/volt curve of the machine was set at 75 percent. The welding current was 220 amperes and the arc voltage was 20 volts. The welding head was set to move along the joint at a speed of 80 inches per minute. The consumable aluminum electrode which had a diameter of 3/64 inch was fed at a speed of 504 inches per minute. The inert gas atmosphere was a mixture of argon and helium, each in an amount of 30 standard cubic feet per hour. An inert atmosphere (Ar) nozzle was placed opposite the welding torch (on the opposite side of the 1/8-inch vertical sheet) and also traveled at 80 inches per minute. This inert gas prevented oxidation of the back side of the weld and possibly improved weld penetration.
After the welding was completed, the joint was subjected to a fracture test and the joint exhibited a shear-tensile strength of 5200 pounds per linear inch of weld.
EXAMPLES 2-5
Employing the same welding equipment, parameters and inert atmosphere, in a like manner four additional joints were welded in each case employing as the vertical member a 1/8 inch thick (by 2 inch by 3 inches) aluminum alloy 5456 extrusion placed upon a 3/16 inch thick aluminum alloy 5456 sheet. The abutting edge of the vertical member had alternating 1 inch lands and slots 1 inch in length and 0.040 inches in height. The operating conditions and the results of shear-tensile strength tests to which 4-inch long sections of each of the welds were subjected are set forth in the following table.
______________________________________Example 2 3 4 5______________________________________Welding current, amps 230 230 230 230Voltage, volts 19 20 20 20Machine speed, inches/min. 75 75 75 75Electrode feed, inches/min. 510 510 510 510Characteristic slope, per- 75 75 75 75centShear-Tensile Strength,pounds/inches of weld 19,300 19,060 18,830 19,180______________________________________
EXAMPLE 6
The same welding technique as in Example 1 was used in this Example 6, except for the differences as noted in the following. The welding current was 220 amperes and the arc voltage was 20.5 volts. The welding head was set to move along the joint at a speed of 75 inches per minute. The consumable aluminum electrode was fed at a speed of 556 inches per minute. The argon atmosphere fed through the nozzle opposite the welding torch was at a rate of 60 standard cubic feet per hour. The slot length was 11/4 inches and the land length was 1/4 inch.
The weld of this Example 6 was subjected to fatigue testing and the single pass fillet weld compared favorably to the performance of two sided fillet welds.
It will be understood that the above description of the present invention is susceptible to various modifications, changes, and adaptions and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.
|
A welding method for forming a fillet welded joint including the steps of placing an abutting edge of a first metal member onto a surface of a second metal member at generally right angles thereto, the abutting edge having a series of alternating lands and slots extending through the entire thickness of the first member, and arc welding employing a consumable electrode to form a fully penetrated fillet weld from one side only of the joint with the weld filling the slots and melting the lands.
| 1
|
[0001] I, claim priority filing date of Apr. 6, 2004 of provisional Application No. 60/560,003
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
[0003] Not Applicable
BACKGROUND FIELD OF INVENTION
[0000]
Current U.S. Class: 4/415: 4/366; 137/436
Intern'l Class: EO3D 001/00
REFERENCES CITED
[0000] U.S. Patent Documents
[0000]
U.S. Pat. No. 6,178,569 Jan. 30, 2001 Quintana . . . 4/427; 4/406; 73/304C; 137/392; 137/558; 340/620
U.S. Pat. No. 5,440,756 Aug. 15, 1995 Weir . . . 4/415; 137/400
U.S. Pat. No. 5,031,254 Jul. 16, 1991 Rise . . . 4/324; 4/415
U.S. Pat. No. 5,524,299 Jun. 11, 1996 Dalfino . . . 4/415, 4/366; 137/410
U.S. Pat. No. 5,185,891 Feb. 16, 1993 Rise . . . 4/324; 4/314; 4/415; 33/531; 33/567
U.S. Pat. No. 4,901,377 Feb. 20, 1990 Weir . . . 4/415; 137/400
U.S. Pat. No. 4,916,762 Apr. 17, 1990 Shaw . . . 4/366; 4/415; 222/16; 222/20; 251/230
U.S. Pat. No. 5,230,104 Jul. 27, 1993 Ocampo . . . 4/415; 4/367; 4/434
U.S. Pat. No. 5,752,281 May 19, 1998 Conner . . . 4/427; 4/415
[0015] “The present invention relates to the fill valve of ordinary toilets with holding tanks or reservoirs, more specifically to improve and expand the scope and function of the toilet fill valve addressing the issues of water shut off, water conservation and preservation, water damage prevention, anti-siphon and back flow prevention.”
DISCUSSION OF PRIOR ART
[0016] Toilet systems, of the reservoir tank type generally installed in American homes, are connected to the potable water supply. The average American home has at least one of these toilets, each of which uses approximately one and one half to three and a half gallons, or more, of water per flush, depending on the age of the toilet.
[0017] Generally, toilet fill valves are made with a float mechanism causing the valve to open when the toilet is flushed as the water leaves the tank and to close once the float is lifted by the water when flush valve closes and the tank or reservoir becomes full.
[0018] Typically these toilet fill valves work fairly well but have several drawbacks that lead to wasting of water, over flow and leaks. These drawbacks result in a myriad of problems from wells running out of water, dirt being introduced into the water lines from low water levels in shallow wells, and septic system failure, to high water and sewage bills for those on public water supply and sewage systems to water damage to the floor of a bathroom, and ceilings and walls of a downstairs room.
[0019] To address these issues manufacturers and inventors began to develop other types of toilet fill valves such as the “Toilet Tank Water Flow Shutoff Apparatus For Preventing Leakage And Overflow, U.S. Pat. No. 5,524,299 of Dalfino, which uses tilting trays to control water level and shutoff of the water supply. Though this device can effectively cause shut off, it tends to have many external moving parts subject to mechanical failure and also uses most of the toilet tank area and servicing as well as installation require more intensive labor and increased expense.
[0020] A quite different approach is taken with the Revised Automatic Water Shut Off For Stuck Open Flush Valves In Toilet Water Tanks, U.S. Pat. No. 5,440,765 of Weir, which utilizes a two cylinder system to force the float upwards to shut off the water supply should a continuous flow or wasting of water occur. Similar to the above is the Toilet Bowl Automatic Flow Shut Off and Water Saver Device, Patent No. 4,901,377 of Weir, that accomplishes the same results with a bellows assembly that lifts the float when the tank remains empty for a period of time beyond that of normal flushing. Both of the foregoing devices utilize a large portion of the toilet tank area to the right of the flapper valve causing access to the flapper to be flanked on all sides and tends to limit service space for repairs, causing repairs to be costly and labor intensive.
[0021] Addressing the issues of conservation, the Water Conserving Toilet Flush Control, U.S. Pat. No. 5,031,254 of Rise, is a device that addresses preventing the wasting of water achieved by limiting the lifting action of the flapper and restricting or preventing automatic operation of flushing. Relatively similar in operation the Water Conserving Toilet Flapper Valve Control, U.S. Pat. No. 5,185,891 of Rise, which in effect limit's the height that the flapper can be lifted achieving the same results as the prior invention of Rise when the flush lever is activated. Though both Rise controls address stopping automatic function of the flapper and limiting the flappers movement they do not address wasting of water when the flapper becomes defective by means of blowout, tear or just ordinary wear of the seal, the results which could lead to a continuous loss of water to the sewer or overflow and water damage.
[0022] Fill valves designed to save water such as the Toilet Water Preservation Device U.S. Pat. No. 5,230,104 of Ocampo, tend to use the flow of wasting water redirecting it to a secondary float device that in turn lifts the primary float device. This device though it appears to be quite functional also renders much the same results as the Weir devices utilizing or cluttering tank space hindering and causing labor intensive costly service when repairing or replacing the flapper or primary float valve. The secondary float fill valve is also still subject to fail in much the same way as the primary float fill valve.
[0023] Adaptations to fill valves such as the Shut-off Device For The Float Valve Assembly Of A Toilet, U.S. Pat. No. 5,752,281 of Conner, designed so that the rotation of the lever arm causes the float valve assembly to rotate to a stop position and stop the flow of water to the toilet tank in the event that the float fails to raise up for any known reason appears as an entirely different approach. While this system would effectively shut off the flow of water it is possible that with the rotating movement of the float assembly, it could eventually cause leakage and overflow from wear due to excessive movement.
[0024] Most of these devices work fairly well shutting off the water, while addressing anti-siphoning of water but do not adequately address backflow prevention, wasting of water if the float fails to be elevated by the water or lack thereof, and or over flow of the bowl or a leaky gasket between tank and toilet. Recently developed toilet fill valves address one or more of these problems. One of the more recent toilet fill valves the FlowManager™ AquaOne Technologies, Inc., addresses most of these problems, incorporates the use of electronic water sensors that detect leaks and overflow. The major drawbacks of such devices are that they require regular and periodical battery maintenance and replacement as well as regular cleaning of the sensor devices that appear as necessary clutter and are actually in the way of cleaning the bowl and or the floor. Additionally, the cleaning of the sensors and the chemicals used, both cleansers and antibacterial toilet additives can cause premature failure. Although the sensor in the bowl will effectively stop overflow of the bowl or bowl in households with children who might lose a toy or otherwise plug the bowl, a floor sensor could present a problem with flushing where bath water is accidentally splashed on it or if a child accidentally misses the bowl and wets the sensor. Electronic valve systems such as the above generally utilize a normally open solenoid valve so the batteries will last a long time if the valve is not triggered shut by a sensor, however if the valve is triggered shut in the case of a flapper leak the batteries would not last very long which would in short time lead to water running to the sewer or worse yet water damage if the bowl was plugged.
[0025] Addressing the issues of toilet tank fill and flush problems and wasting of water with control devices has made significant progress in the Positive Shut-off, Metered Water Control System For Flush Tanks, U.S. Pat. No. 4,916,762, by Shaw. This device utilizes the flow of water to turn a vaned water wheel. A worm gear attached to the water wheel drives a spur gear which in turn rotates a second spur and worm gear. The worm gear of the secondary or intermediate gear assembly then engages a spur gear seated in a ratchet and cam assembly. The cam of the ratchet cam assembly controls both opening and closing of a stopper. The cam is ratcheted to the start position by a lever connected to the flush lever of the toilet to cause the stopper to dislodge from its seat when the toilet is flushed to allow water to pass or flow driving the water wheel which causes the cam to turn and reseat the stopper after the desired amount of water has been metered through the system. Although this device is impressive it has the possibility of lockup of the drive system where spur gears are used as opposed to the helical gears.
[0026] Helical gears are similar to spur gears and of the same family of gears, however the teeth of a helical gear are angled to the gear face to better mesh with the driving worm gear insuring greater performance while preventing binding or lockup.
[0027] While addressing anti-siphon ability as with the other devices heretofore mentioned this particular device also addresses backflow prevention when the stopper is reseated by water pressure, but will not stop backflow if water pressure is lost during fill up. As previously discussed above this invention utilizes a start arm with a pawl to ratchet forward the cam to allow a predetermined volume of water by notches fixed in the cam. While this method appears to be able to work well a shortcoming to address is each toilet with a different tank capacity would need a special cam for that particular volume of water, additionally this ratchet cam system does not address the ability to adjust the volume of water metered so a 3.5 gallon valve will not service the 1.5 gallon tank of a newer toilet or vise versa. In other words one size does not fit all due to the arrangement of the fixed setting or position of notches in the cam and the ratcheting mechanism.
SUMMARY OF THE INVENTION
[0028] Accordingly, the reader will see that the instant invention is a toilet fill valve designed to operate in conjunction with or without its float assembly by providing a limited amount of water to any given toilet tank during flushing sufficient to allow a complete flush and performing a positive shut off of the water supply should the flushing operation fail for any reason. Should the float or flapper fail to operate properly and only after the maximum amount of water limited by volume has passed to the tank of a toilet, or water closet, the flo-control valve of the instant invention will close and prevent further entry of water into the tank for the purpose of eliminating running or wasting of water, preventing over flow and water damage. Additionally the valve is equipped with a backflow prevention check valve to stop any possible reverse flow in case of water pressure loss. The volume limiting shut-off action of the flo-control system, which can be used any common toilet tank of sufficient dimension, comprises a flo-control valve positioned to turn on and shut off the flow of water from the feed line to the tank. The water flows from the feed line into the inlet through a channel in which the flo-control valve is positioned, flow continues to a vaned water driven impeller assembly and thence to the inlet section of the float valve and on to the outlet of said float valve such that, during water flow the water driven impeller is caused to rotate within a channeled flow chamber. A worm gear, attached to the water driven impeller rotating therewith then drives a helical spur gear that is part of a vertical secondary gear assembly having a second worm gear on the upper end thereof. The worm gear of the intermediate gear assembly engages a horizontal helical spur gear of the same dimension which in turn rotates the final drive worm gear, which retracts the hold/release lever. The final drive worm gear, and the hold/release leaver, control the positioning of the flo-control valve in either a hold open or a released closed position.
[0029] When the toilet is flushed, the actuating lever depresses and dislodges the flo-control valve to start the flow of water to fill the toilet tank. When the flo-control valve is depressed the actuator lever causes the hold/release lever to disengage and retract from the final quad worm gear allowing the actuator lever to drop below the hold/release lever. When the flush lever is released the upward movement of a spring connected to the lower portion of the flo-control valve causes the hold/release lever to engage the final drive double thread worm gear while leaving the flo-control valve open.
[0030] The water flows through the inlet valve, through the open the flow-control valve past the impeller causing it to rotate, driving the gear assembly to cause the final drive double thread worm gear to retract the hold/release lever releasing and allowing the actuator lever to be elevated by the closing of the flo-control actuator valve, thereby effectively shutting off the flow of water. Noting that the shutting off the flow of water by the flo-control actuator valve is dependant on the failure of one or more of the flushing components of the toilet or a toilet tank with the full requirement of water volume allowed or limited by the flo-control. An alternate means of controlling the actuator release is achieved by removing the hold release lever system and replacing it with the slotted disk system utilizing the same embodiment and majority of the components with some alterations which will be discussed further on.
[0031] Ideally the float assembly affixed to the uppermost portion of the valve body will be activated prior to the conclusion of the closing of the flo-control actuator valve. The flo-control actuator valve will reset to its maximum allowance of water volume each time the flush lever is depressed. Any toilet tank that has a lesser volume capacity will cause the float valve to elevate and effectively shut off the flow of water. Should the float or flapper fail to close, the tank would call for more water than allowed and the flo-control valve will shut off the flow of water when the limited volume of water has been reached effectively conserving water and reducing the volume of sewage waste caused by toilets that continuously run. In effect and operation the function of the instant invention is to shut off the water supply upon any malfunction of the toilet flushing system for any reason.
[0032] The reader will note that there are two interchangeable water delivery systems one being a float assembly and the other being a float eliminator. When using a float assembly the flo-control can be used universally in any tank irregardless to a lesser tank capacity. For instance a 1½ gallon tank will cause the float to shut the flow of water off at 1½ gallons and the flo-control will stop running. If there is a flapper leak or other malfunction the flo-control will still shut off at 3½ gallons limiting the maximum flow of water as its intended safety feature. The flo-control will also reset to its maximum allowance at every flush.
[0033] The second delivery system is the float eliminator. This system attaches to the flo-control the same way as the float assembly. However this system is simply a channeling device that directs the water downward towards the base of the tank for fill up from a delivery tube, with a replenish tube receiver at its upper most portion for removeably connecting the replenish tube to restore the water level in the bowl during fill up.
OBJECTS AND ADVANTAGES
[0034] Accordingly, being designed to address the problems of toilets that have been discussed with the prior art, several objects and advantages of the present invention are:
(a) to provide a limited supply of water by volume to any given toilet tank per flush; (b) to provide a failsafe positive shutoff of the water feed line when the maximum limit of water by volume has been reached; (c) to prevent overflow and limit the extent of water damage from a plugged toilet; (d) to conserve water, and to prevent wasting of water; (e) to reduce municipal waste water treatment costs; (f) to reduce the production of sewage pollution into the environment; (g) to provide a positive means of anti-siphon and backflow prevention.
[0042] Further objects and advantages are to provide a cost effective easy to install toilet fill valve that will not interfere with servicing of other toilet tank parts. For instance with the present invention should the flapper of the flush valve not seat properly or worse yet rupture the water supply will be shut off and the toilet tank will be left empty and ready for easy no muss or fuss servicing. A new flapper can be installed or the flapper can be adjusted without taking too much time for cleanup, and once the repair is complete all that is necessary to return to normal flushing operation is to activate the flow of water by depressing the flush lever of the toilet tank and your back in business.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWING
[0043] The present invention will be better understood from the following detailed description as depicted in the drawings in which like reference numerals refer to like parts; closely related figures have the same number but different alphabetic suffixes.
[0044] FIG. 1 is a side view of a typical conventional toilet, with the tank partially cut away to reveal its interior, incorporating the automatic water limiting, supply shut off valve of the present invention;
[0045] FIG. 2 is a top plan view of the principal portion of the toilet tank of FIG. 1 with the lid removed, taken on line I-I of FIG. 1 ;
[0046] FIG. 3 is a cutaway front view of the inlet fitting, backflow chamber assembly and flo-control valve.
[0047] FIG. 3A is a cutaway view side view of the flo-control assembly;
[0048] FIG. 3B is a front view of the flo-control drive impeller and the impeller drive flow chamber base plate, taken on line II-II and line III-III of FIG. 3A ;
[0049] FIG. 4 is a front view of the actuator lever and lever flush extension, taken on line II-II of FIG. 3A ;
[0050] FIG. 4A is a side view of the actuator lever;
[0051] FIG. 5 is a interior front view of the flo-control body rear wall, taken on line II-II and line III-III of FIG. 3A ;
[0052] FIG. 5A is a interior rear view of the flo-control cover, taken on line II-II and line III-III of FIG. 3A ;
[0053] FIG. 6 is a elevated view of the hold/release lever;
[0054] FIG. 7 is a cut away view of the float valve coupling;
[0055] FIG. 8 is a front cut away view of a float eliminator and replenish tube.
[0056] FIG. 9 is a cut away side view of the alternate adjustable volume flo-control assembly using a slotted disk release system;
[0057] FIG. 9A is a rear view of the slotted disk and gear for the slotted disk release system;
[0058] FIG. 9B is a side view of the adjusting pegs for the slotted disk release system;
[0059] FIG. 9C is a front view of the replacement actuator for the alternate volume flo-control release system taken on line II-II of FIG. 3A , for the slotted disk release system;
[0060] FIG. 9D is a side view of the replacement actuator for the slotted disk release system;
DETAILED DESCRIPTION OF THE INVENTION
[0061] The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor for those so skilled to do so.
[0062] FIG. 1 is a side view of a conventional toilet, of the type universally found in most homes in the United States and North America, which is fitted with a water limiting flo-control 32 , in accordance with the present invention. In the conventional home toilet, a ball cock assembly comprising a float arm, and float ball is mounted at the upper end of a water tube for closing an inlet valve via a mechanical linkage when the tank is filled to a predetermined level. In the present invention a float valve assembly 122 , is affixed to the uppermost portion of the water limiting flo-control 32 , by means of a float coupling 124 .
[0063] The illustrated toilet comprises a toilet bowl 12 , and a pedestal 13 , with a tank 10 , mounted over the rear extension of toilet bowl and pedestal 13 . Water supply is introduced by means of a water feed line 34 , which is connected by known means of a standard sized fitting, as currently used with flush tanks, providing a seal able mount to the tank 10 , and a inlet fitting 36 , of the water limiting flo-control 32 . Water received in tank 10 which exceeds the tank's design capacity spills into an overflow tube 26 , wherefrom it is discharged to the bowl 12 . The main tank outlet 22 , is normally closed by a flapper 20 . When water from overflow tube 26 , or tank outlet 22 , or both is introduced into toilet bowl 12 , the level of water in bowl 12 , is raised until it exceeds the waste outlet of a flush trap 28 , causing the water to flow from bowl 12 , by siphoning action. Water, and waste products, continue to flow from bowl 12 , as long as sufficient water enters bowl 12 .
[0064] FIG. 2 is a top plan view of the principal portion of the toilet tank of FIG. 1 with the lid removed, illustrating the position of the flapper 20 , along line I-I of FIG. 1 and the position of the water limiting flo-control 32 to the left most portion of the tank 10 . A flush handle 14 , located in the upper left front area of the tank 10 , is depressed to activate the flushing operation of the toilet. When depressed the flush handle lifts a flush rod 16 , to lift open the flapper 20 , by means of a flapper flush linkage 18 , simultaneously the flush rod 16 , by means of a flo-control flush linkage 24 , to a actuator lever flush extension 106 , activates the water limiting flo-control 32 , allowing water to flow to the tank 10 .
[0065] FIGS. 3-3B are illustrations of the assembled components of the water limiting flo-control 32 , the Automatic Water Limiting, Supply Shut Off Safety Valve system according to the preferred embodiment of the present invention. The preferred embodiment is intended to limit the passing of up to 3.5 gallons of water by volume to the tank 10 , and to shut off the water supply. FIGS. 4-4A are illustrations of the actuator lever 104 , and actuator lever flush extension 106 . FIGS. 5-5A illustrate partial views of the interior of the flo-control body 66 , flo-control cover 72 , and the flo-control body seal 78 . FIG. 6 illustrates an elevated view of a hold/release lever 110 . FIG. 7 illustrates a sectional front view of the float valve coupling 124 . FIG. 8 illustrates a float eliminator 125 , and a replenish tube 30 . FIGS. 9-9B illustrate a water volume adjustable alternate releasing mechanism for releasing the flo-control valve 58 , by means of a slotted disk 140 , and volume adjusting pegs 150 . FIGS. 9C and 9D illustrate a alternate actuator for use with the disk mechanism.
[0066] The preferred embodiment of the present invention is preferably molded in three sections of a plastic material that may be sealed when joined with o rings or other suitable gasket type or threading seal material. Section one illustrated in FIG. 3 , being the assembled parts of a inlet fitting 36 , comprised of a water inlet chamber 38 , fitted with a particle screen 40 , for trapping any foreign particles that may enter the water supply. Slightly above said inlet chamber 38 , molded in the embodiment of the inlet fitting is a backflow prevention chamber 42 , in which a backflow seat 44 is molded within the embodiment with a minimum 1/4 inch diameter opening for water flow between the inlet chamber 38 , and the backflow prevention chamber 42 . Freely sitting on said backflow seat 44 , is a backflow check ball 46 , made of sufficient rubberized or metal material as to be non corrosive, non-buoyant and of sufficient diameter at least 3/16 of an inch larger than the opening for water flow. During water flow, the force of the water will lift the backflow check ball 46 , off the backflow seat 44 , allowing free flow of the water through the system. Upon shutoff of the float valve assembly 122 , or the flo-control valve 58 , or at any time should the water supply lose its pressure the water will cease to flow causing the backflow check ball 46 , directed by the tapered wall of the backflow prevention chamber 42 , to reseat itself preventing reverse flow of water. At the upper portion of backflow prevention chamber 42 , is a mounting flange 48 , of standard size to fit the receiving hole of the toilet tank 10 , fitted with the standard size flange seal 50 , of appropriate material between the mounting flange 48 , and the tank 10 , affixed or mounted to said tank 10 , by means of the standard flange nut not shown for obvious reason.
[0067] Threaded into the upper most end of the inlet fitting 36 , and sealed by means of plumber joint material is a flo-control inlet coupling 52 . A flo-control valve 58 , fitted with a o ring seal 60 , is attached to a open cross spring retainer pin 54 , of the flo-control inlet coupling 52 , by means of a flo-control valve spring 56 , preferably made of a non corrosive material such as stainless steel of sufficient diameter wire to create enough upward pressure to seat and hold said flo-control valve 58 , in its closed position while still allowing the flo-control valve 58 , to be unseated without excessive force.
[0068] The upper most portion of the flo-control inlet coupling 52 , is threaded and sealed by means of plumber joint material into a coupling receiver 53 . At this point the flo-control valve 58 , is positioned within the center most portion of the flo-control chamber 62 , of preferred embodiment of the flo-control body 66 . FIG. 3A .
[0069] Section two illustrated in FIG. 3A , FIG. 3B and FIG. 5 , comprises a flo-control body 66 , preferably molded of a plastic material in one piece. Sealed closure is obtained by snapping on a flo-control cover 72 , FIG. 5A , that is sealed by placing a flo-control body seal 78 , between the flo-control cover 72 , and the flo-control body 66 , and placing a actuator o ring 108 , in a actuator receiver 77 , prior to aligning the actuator with a cover actuator hole 76 , then snapping the flo-control cover 72 , in place. Sealing of the housing is necessary to stop water flow when the float valve assembly 122 , closes and to meet the plumbing requirements for “anti-siphoning”. The composition used for flo-control body 66 , would be of the manufacturers choice.
[0070] The flo-control cover 72 , FIG. 5 , is comprised of one piece molded in similar a plastic material as the flo-control body 66 , and is snapped into place by means of a set of flo-control cover guides 73 , mated to said guides by means of a matching set of cover guide receivers 74 , held in place by a body/cover locking ridge 7 . Said flo-control cover 72 , aids in directing the flow of water by means of a set of cover flow guides 75 , that aid in stabilizing the rotation of the drive impeller 80 .
[0071] Mating of a flo-control valve 58 , and a flo-control valve o ring 60 , to a flo-control valve seat 64 , is accomplished by means of threading a flo-control inlet coupling 52 , into the lower most portion of a flo-control chamber 62 , of the preferred embodiment of the flo-control body 66 , thereby extending the upper most portion of a flo-control valve 58 , through the upper most portion of the flo-control chamber 62 , between the walls of a lower actuator guide 117 .
[0072] When unseated by means of a actuator lever 104 , the flo-control valve 58 , allows water to flow through said valve into the upper most portion of the flo-control valve chamber 62 , and on into a impeller drive flow chamber 68 , FIGS. 3A and 3B by means of one of two body flow guides 65 , FIG. 5 , creating an opening between said chambers. Preferably molded of a plastic material the components of the impeller drive flow chamber 68 , are comprised of a impeller drive flow chamber base plate 69 , and the flo-control cover 72 . The impeller drive flow chamber base plate 69 , directs the flow of water by means of a split flow guide 70 , which forces the flow of water to turn a drive impeller 80 . The split flow guide 70 , FIG. 3B , is comprised of two parallel walls of sufficient extension at a 90 degree angle outwardly from the face of the impeller drive flow chamber base plate 69 , so as to allow sufficient space to form a chamber when covered with said flo-control cover 72 , to allow free wheeling of a drive impeller 80 . A spacing peg 71 , of equal extension molded to said base plate 69 , opposite the split flow guide 70 , assures equal distance between said impeller drive flow chamber base plate 69 , and the flo-control cover 72 , at all points.
[0073] The impeller drive flow chamber 68 , houses the drive impeller 80 , FIG. 3B , molded as a one piece unit with a impeller primary drive worm gear 82 , is centered through said impeller drive flow chamber base plate 69 , by means of a impeller drive shaft 84 , of a non corrosive metal preferably brass, mounted horizontally from front to rear with a primary drive shaft bushing 83 , between a drive shaft receiver 85 , recessed in the flo-control cover 72 , and a body drive shaft receiver 94 , recessed in the flo-control body 66 , locked in a certain position on said impeller drive shaft 84 , by means of a retainer ring 86 , as shown in FIGS. 3A and 3B . Said impeller 80 , solidly connected to primary drive worm gear 84 , are caused to rotate by means of the force of water flow through the impeller drive flow chamber 68 , against a impeller fin 81 , in the flow path. There are nine said impeller fins 81 , to insure a fin will enter the flow path as a fin leaves the flow path maintaining a constant rotation of the drive impeller 80 , during water flow with a minimum of four fins in the flow path at all times FIG. 3B .
[0074] The primary drive worm gear 82 , engages a secondary drive helical gear 88 , solidly molded as a one piece unit with a secondary drive worm gear 90 , of a suitable material. Said secondary helical gear meshes with said primary worm gear 82 , at its 90 degree right center horizontally. Said secondary worm gear 90 , is vertically positioned by means of two secondary drive gear brackets 92 , mounted horizontally parallel to each other, one above the other, spaced a sufficient distance apart so as to accommodate the length of said secondary drive helical gear 88 , and secondary drive worm gear 90 . Said secondary drive gear brackets 92 , are fitted from front to back by means of the secondary drive bracket mounts 96 , molded into the rear most side of the impeller drive flow chamber base plate 69 , and the front most side of the rear wall of the flo-control body 66 , illustrated in FIG. 3A .
[0075] The secondary drive worm gear 90 , then engages a final drive helical gear 98 , solidly molded as a one piece unit with a final drive double thread worm gear 100 , of a suitable material. Said final drive helical gear 98 , meshes with said secondary worm gear 90 , at its center 90 degrees to its left and centered above said primary worm gear 82 , and final drive double thread worm gear 100 , is horizontally positioned from front to back by means of two final drive gear shaft studs 102 , one being molded to the rear side of the impeller drive flow chamber base plate 69 , 180 degrees horizontally to the other being molded to the front side of the rear wall of the flo-control body 66 , spaced a sufficient distance apart so as to accommodate the length of said final drive gears.
[0076] When flush handle 14 , FIG. 2 , is depressed the flo-control flush linkage 24 , elevates the actuator lever flush extension 106 , FIG. 3B and FIG. 4 , Connected by means of a lever connector 107 , causing a actuator lever 104 , by means of a beveled surface 105 , to move in a downward motion between a lower actuator guide 117 , and a upper actuator guide 118 , FIG. 5 , pushing by a hold/release lever 110 . The hold/release lever 110 , is connected to and positioned by means of two retainer pins 109 FIG. 6 , mated to two retainer slots 116 , in a hold/release lever receiver 115 , and a hold/release lever spring 112 , composed of a non corrosive material of sufficient diameter wire to provide a slight forward tension FIG. 3A , held in position by two spring pins 113 , one pin being centered molded within the hold/release lever receiver 115 , and the other being centered molded to the rear most end of the hold/release lever 110 . The pushing, by means of the beveled surface 105 , of the actuator lever 104 , causes the hold/release lever 110 , to move rearward by means of a mated beveled surface 111 , into the hold/release lever receiver 115 , molded into the preferred embodiment of the flo-control body, FIGS. 3A and 5 . After the actuator lever 104 , pushes past the hold/release lever 110 , the hold/release lever 110 , by means of tension supplied by said hold/release lever spring 112 , moves forward resting on top of said actuator lever 104 . Simultaneously said actuator lever 104 , unseats and opens the flo-control valve 58 , in the same downward motion. When the flush handle 14 is released it returns to its normal resting position allowing the actuator lever 104 , by means of tension of the flo-control valve spring 56 , to be pushed upward lifting the hold/release lever 110 , thereby gearably engaging a gear rack 114 , molded to the upper most surface of said hold/release lever 110 FIG. 6 , to the final drive double thread worm gear 100 , thereby holding the flo-control valve open.
[0077] The drive impeller 80 , is caused to rotate by means of the force of water flowing through the impeller drive flow chamber 68 . The rotational energy delivered to the final drive double thread worm gear 100 , being gearably linked to said drive impeller 80 , as heretofore described causes the hold/release lever 110 , to retract into the hold/release lever receiver 115 , by means of said gear rack 114 , thereby releasing the actuator lever 104 . Upon release, the actuator leaver 104 , is repositioned above said hold/release lever 110 , by means of elevation due to the upward movement of the flo-control valve 58 , being reseated by means of the force of the flo-control valve spring 56 terminating the flow of water completing the flush cycle. The water passes through the impeller drive flow chamber 68 , to the outlet by means of one of two body flow guides 65 , molded within the flo-control body 66 , at its upper most interior forcing the water out the water outlet 120 , FIG. 5 .
[0078] The reader will note that there are two ways in which the water can be delivered to the tank 10 . The first and most obvious is by means of a float assembly 122 , illustrated in FIGS. 1 and 2 . The alternate is by means of a float eliminator 125 , FIG. 8 , which will be discussed further on.
[0079] Section three is of course the float assembly 122 , FIG. 1 and FIG. 2 , not described for obvious reason is attached to the present invention by means of a water outlet 120 , at the upper most end of the flo-control 32 , FIGS. 1 and 2 , on line II-II of FIG. 3A , molded in the structure of the preferred embodiment of the flo-control body 66 , by means of mating thread of the lower most end of a float coupling 124 FIG. 7 , to the thread of said water outlet 120 , sealed with an o ring or other suitable gasket type or thread sealing material. Threading or bonding with a suitable bonding agent of the coupling 124 , to the float valve inlet while eliminating the older type extension tube from the float valve to the tank mount. Where the float valve is now connected to the flo-control 32 , the siphon tube becomes a replenish tube 30 FIGS. 1, 2 and 8 , which is removeably attached the former siphon tube receiver of the float assembly 122 , for the purpose of replenishing the proper water level to the bowl 12 .
[0080] The alternate to the float assembly is the preferred embodiment of the float eliminator 125 , FIG. 8 , which is a one piece mold of appropriate plastic material composed of a eliminator inlet 126 , threaded to mate the outlet 120 , attaching to the flo-control the same way as the float assembly 122 . However, this system is simply a channeling device that directs the water downward towards the base of the tank for fill up by means of a eliminator delivery tube 127 , and a eliminator outlet 128 , with a eliminator replenish tube receiver 130 , at its upper most portion for removeably connecting the replenish tube 30 . The replenish tube 30 is attached to the over flow tube 26 , by means of a replenish tube clip 132 , to restore the water level in the bowl during fill up. With this optional float eliminator 125 , attached to the flo-control 32 , the flo-control will run to its full limit of 3 V 2 gallons and shut off every time. In order to fit the flo-control to different capacity tanks the hold/release lever 110 , would have to be shortened at its mated beveled surface 111 , end. That is to say for example if the hold/release lever 110 , required to be retracted ⅜ of an inch for release to shut off the flo-control at 4½ gallons then it would be required to be retracted ⅛ of an inch to shut off at 1½ gallons. The length would have to be shortened 1/4 inch for that adjustment. This would require at least three different size hold/release levers and each flo-control would be marked appropriately on its packaging as to its limit.
[0081] In addition to the alternate float eliminator 125 , for the purpose of adjusting the gallon per flush volume of the flo-control 32 , illustrated in FIGS. 9-9D is a modified adjustable volume flo-control mechanism. The preferred embodiment remains primarily the same up to the point of the final drive helical gear 98 , therefore the foregoing description above will not be repeated to that point. In the alternative adjustable release mechanism the final drive helical gear is solidly connected to a final drive spur gear 134 . The final drive spur gearl 34 , drives a jack shaft spur gear 136 , of the same diameter, having a tapered spur gear push 137 , mounted with a jack shaft spring 139 , to allow for gear disengagement, replacing of the heretofore described hold release lever receiver 115 , by means of a jack shaft 138 , molded to the embodiment of the flo-control body 66 . The jack shaft gear drives a slotted disk 140 , solidly connected to a disk spur gear 142 also of the same diameter, located to the rear of the primary drive worm gear 82 , replacing the primary drive bushing 83 , as earlier described. The slotted disk 140 , FIG. 9A , comprises a actuator release slot 146 , FIG. 9A , the means which allows opening and closing of the flo-control valve 58 . The adjustment of gallons allowed from 1.5 gallons to 3.5 gallons is accomplished by means of a volume adjusting slot 148 , and mating volume adjusting pegs 150 , FIG. 9B . Each of the three volume adjusting pegs are of a different diameter to fit the volume adjusting slot 148 , allowing the slotted disk 140 , to turn when the toilet is flushed to the limit set by the peg 150 , inserted into a adjusting peg receiver 152 , illustrated in FIG. 9 , sealed with a adjusting peg o ring 153 . The slotted disk 140 , is held in the valve closed position by means of a actuator foot 156 , of the modified actuator 154 , illustrated in FIGS. 9C and 9D , mated to the actuator release slot 146 , FIG. 9A . The modified actuator lever 154 , of the alternate valve control mechanism is primarily the same with three small but important differences the first being the actuator foot 156 , the second is a tapered spur gear push 158 , and a start spring receiver hole 145 , one of which also located in the slotted disk 140 . When the flush handle 14 , of the toilet is depressed the slotted disk 140 , is released by the actuator foot 156 and the disengaging the jack shaft spur gear 136 , by means of pushing the mated tapered spur gear push 137 , from said actuator gear push 158 means, and is rotated to the limit of the selected volume adjusting peg 150 , by means of a start spring 144 , inserted into the slotted disk 140 , and the actuator lever 154 , by means of the start spring receiver hole 145 , simultaneously dislodging and opening the actuator valve 58 . When the flush handle 14 , is released the jack shaft spur gear re-engages. The actuator valve is held open by the slotted disk until the selected volume of water rotates the actuator release slot 146 , over the actuator foot 156 , by means of the gearably linked drive impeller thereby allowing the flo-control valve 58 , to close.
[0082] Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiments which can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.
|
A geared mechanical device designed to limit a finite amount of water per flush to a tank reservoir of the common household toilet, providing positive shutoff of flow and anti-siphon backflow prevention. The toilet is flushed, the actuator leaver actuates the flo-control valve by means of linkage to the flush lever. The water enters the back flow chamber into the primary valve chamber then to the flow control chamber, and on to the float valve into the toilet tank for fill up. Force of the water rotates the drive impeller gearably linked to the hold/release lever. On release the flo-control valve closes. The backflow prevention chamber allows the water to pass in the direction of flow and reseats itself when the flow has stopped or if water pressure is lost at any time eliminating a need for a anti-siphon tube. The anti-siphon tube is replaced by a replenish tube to restore water level to the bowl. A float eliminator may be affixed to the flo-control in place of the float valve. For the purpose of adjusting the volume of water per flush an alternate slotted disk mechanism can be fitted to the flo-control and gearably connected with spur gear in place of the final drive worm gear, a jack shaft, and jack shaft spur gear in the position of the formerly described hold/release lever, and a solidly connected spur gear to the slotted disk. The actuator is replaced with a footed actuator. The function remains the same as do the heretofore described components.
| 5
|
CROSS REFERENCE TO RELATED APPLICATION
This application is related to Provisional Patent Application Ser. No. 61/294,514, filed Jan. 13, 2010 and claims priority thereto.
GOVERNMENT INTEREST
This invention was made with Government support under Contract No. DE-FC07-07ID14779 awarded by the Department of Energy. The Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains in general to pressurizers for pressurized water nuclear reactor power generating systems and more particularly to the thermal liners attached to the interior of the surge nozzles for such pressurizers.
2. Related Art
The primary side of nuclear reactor power generating systems which are cooled with water under pressure comprises a closed circuit which is isolated and in heat exchange relationship with a secondary side for the production of useful energy. The primary side comprises the reactor vessel enclosing a core internal structure that supports a plurality of fuel assemblies containing fissile material, the primary circuit within heat exchange steam generators, the inner volume of a pressurizer, pumps and pipes for circulating pressurized water; the pipes connecting each of the steam generators and pumps to the reactor vessel independently. Each of the parts of the primary side comprising a steam generator, a pump and a system of pipes which are connected to the vessel form a loop of the primary side.
For the purpose of illustration, FIG. 1 shows a simplified nuclear reactor primary system, including a generally cylindrical reactor pressure vessel 10 having a closure head 12 enclosing a nuclear core 14 . A liquid reactor coolant, such as water, is pumped into the vessel 10 by pump 16 through the core 14 where heat energy is absorbed and is discharged to a heat exchanger 18 , typically referred to as a steam generator, in which heat is transferred to a utilization circuit (not shown), such as a steam driven turbine generator. The reactor coolant is then returned to the pump 16 completing the primary loop. Typically, a plurality of the above-described loops are connected to a single reactor vessel 10 by reactor coolant piping 20 . The primary side is maintained at a high pressure in the order of 155 bars by means of a pressurizer 22 that is connected to one of the loops of the primary side.
The pressurizer makes it possible to keep the pressure in the primary circuit between predetermined limits either by spraying the primary coolant fluid when the pressure tends to exceed the permissible upper limit or by electrical heating of the primary fluid when the pressure tends to fall below the permissible lower limit. These operations are carried out inside the pressurizer which comprises a generally cylindrical casing arranged with its axis vertical and having its lower and upper parts closed by means of domed ends. The lower domed end has sleeves passing through it in which electrical heaters are introduced into the pressurizer. The lower domed end also has a combined inlet and outlet surge nozzle that communicates directly with the primary loop piping 20 to maintain the pressure within the primary circuit within design limits.
As can be appreciated from FIGS. 2 , 3 and 5 , the surge nozzles 24 of the pressurizers 22 include thermal sleeves or liners 26 to reduce the effect of thermal transients on the fatigue of the nozzles. These thermal sleeves have typically been welded to or explosively expanded into the nozzle 24 . FIG. 2 shows the thermal sleeve 26 welded at one axial location 28 along the interior of the nozzle. A spacer 29 is positioned between the thermal sleeve 26 and the nozzle 24 , proximate an inner end to minimize vibration of the sleeve, to keep the sleeve centered in the nozzle during welding, and to maintain a radial gap between the nozzle and the sleeve as a thermal barrier. FIG. 3 shows the thermal sleeve 26 explosively expanded at the expansion zone 30 , into the interior surface of the surge nozzle 24 . Both of these installation techniques have drawbacks. Welding the thermal sleeve to the nozzle occurs only over a portion of the circumference, since welding over the entire circumference would result in unacceptable stresses in the thermal sleeve during certain transients. This results in non-uniform by-pass behind the thermal sleeve and bending in the nozzle. More particularly, the welding occurs on the interior of the nozzle typically over a 45° arc length. During cold water in-surge transients, the thermal sleeve contracts relative to the nozzle, and the asymmetric welding pattern results in a gap between the thermal sleeve and nozzle opposite the weld. Explosive expansion can also result in non-uniform expansion, and residual stresses in the sleeve material. The thermal sleeve is tightly fit to a groove machined into the cladding. There is no feature to center the thermal sleeve in the nozzle so contraction of the thermal sleeve during cold in-surge transients will result in non-uniform radial gaps, and hence additional thermal and bending stresses in the nozzle. In addition, explosive expansion is not always a well controlled process, and requires special permitting and handling which creates difficulties for the manufacturers.
Accordingly, an improved means for attaching the thermal sleeve to the nozzle is desired that will keep the thermal sleeve centered in the nozzle and not create non-uniform gaps between the sleeve and the interior of the nozzle.
SUMMARY OF THE INVENTION
These and other objects are achieved by this invention which provides a pressure vessel, and more particularly a pressurizer pressure vessel having a surge nozzle with a thermal sleeve mechanically attached to the interior thereof. The surge nozzle has an axial dimension and a first opening adjacent an interior of the pressure vessel at one end of the axial dimension and a second opening adjacent an exterior of the pressure vessel at a second end of the axial dimension. The thermal sleeve lines at least a portion of the interior of the surge nozzle along the axial dimension with a first end of the thermal sleeve proximate the first opening and a second end of the thermal sleeve proximate the second opening. A plurality of mechanical couplings connect the interior of the surge nozzle and thermal sleeve proximate the first end and the first opening and supports the thermal sleeve in the axial direction, with the first plurality of mechanical couplings being circumferentially spaced around the interior of the surge nozzle. A second plurality of mechanical couplings connect the interior of the surge nozzle and the thermal sleeve proximate the second end and the second opening and secures the thermal sleeve from rotation, with at least some of the second plurality of mechanical couplings circumferentially spaced around the interior of the surge nozzle. Preferably, each of the first plurality of mechanical couplings and the second plurality of mechanical couplings are equally spaced circumferentially around the thermal sleeve.
In one embodiment, each of the first plurality of mechanical couplings are substantially at a first axial location and each of the second plurality of mechanical couplings are substantially at a second axial location. In the one embodiment, the first plurality of mechanical couplings are a key and slot coupling wherein the keys extend through a slotted opening in the thermal sleeve and into a groove formed in the interior of the surge nozzle. Preferably, the keys and slots are elongated and extend in the circumferential direction. Desirably, a head of the key is larger than the slot in the thermal sleeve through which the key extends and the head of the key is mated to and welded to an interior surface of the thermal sleeve and a portion of the key that fits within the slot on the interior of the surge nozzle is welded to the thermal sleeve.
In another embodiment, the second plurality of mechanical couplings are key and slot couplings wherein the slots are formed in the second end of the thermal sleeve and the keys protrude radially inward from the interior of the surge nozzle. Desirably, the slots in the second plurality of mechanical couplings are open ended and are elongated and extend in the axial direction.
BRIEF DESCRIPTION OF THE DRAWINGS
A further understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:
FIG. 1 is a simplified schematic of a nuclear reactor system to which this invention can be applied;
FIG. 2 is a sectional view of a portion of a surge nozzle with a welded thermal sleeve;
FIG. 3 is a sectional view of a surge nozzle with an explosively expanded thermal sleeve;
FIG. 4 is a partial sectional view of a pressurizer; and
FIG. 5 is a sectional view of a surge nozzle with a mechanically attached thermal sleeve in accordance with this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 4 , there is shown a pressurizer 22 for a pressurized water nuclear power plant system. The pressurizer 22 comprises a pressure vessel having a vertically oriented cylindrical shell 32 , a first or upper hemispherical head portion 34 and a second or lower hemispherical head portion 36 . A cylindrical skirt 38 extends downwardly from the lower head portion 36 and has a flange 40 fastened thereto by welding or other means to form a support structure for the vessel. The upper head portion 34 has a manhole or man-way 42 for servicing the interior of the vessel, one or more nozzles 44 , respectively, in fluid communication with a safety valve (not shown) and a spray nozzle 46 disposed therein. The spray nozzle 46 is in fluid communication with a supply of relatively cool primary fluid and has means associated therewith (not shown), which controls the flow of the relatively cool fluid to the pressurizer.
A plurality of nozzles 48 are vertically disposed in the lower head 36 and a plurality of straight tubular electrical immersion heating elements 50 extend through the nozzles 48 and into the pressurizer 22 . The heating elements 50 have a metal sheath covering the outer surface thereof and seal welds are formed between the metal sheaths and the nozzles 48 . To support the heating elements in the pressurizer, a single or a plurality of support plates 52 are disposed transversely in the lower portion thereof. The support plate(s) 52 have a plurality of holes 54 which receive the heating elements 50 .
A combined inlet and outlet nozzle 24 , commonly referred to as a surge nozzle is centrally disposed in the lower head 36 and places the pressurizer in fluid communication with the primary fluid system of the pressurized water nuclear reactor power plant.
As previously mentioned, the surge nozzles of pressurizers include the thermal sleeves or liners previously discussed with regard to FIGS. 2 and 3 , which are employed to reduce the effect of thermal transients on the fatigue of the nozzle. In accordance with this invention, the thermal sleeve is attached to the bore of nozzle by means of a mechanical attachment. The attachment means of this invention allows for the sleeve to fully expand in the longitudinal direction as well as radially, which is necessary to address thermal transients experienced by the surge nozzle. The sleeve attachment is accomplished by the inclusion of annular grooves in the nozzle bore, which receive supporting keys to provide axial support for the sleeve. To prevent rotational movement, slots are provided in the lower end of the sleeve which receive keys machined in the bore of the nozzle 24 .
FIG. 5 illustrates a sectional view of surge nozzle 24 having a thermal sleeve 26 lining the interior surface thereof, which is attached to the nozzle in accordance with this invention. The thermal sleeve 26 is supported at the top end of the nozzle 24 by radial keys 58 . The radial keys fit through openings 60 in the thermal sleeve 26 , and are welded around their perimeter 62 on the bore of the thermal sleeve 26 . Preferably, on one side the radial keys 58 have enlarged heads that are captured by the inner surface of the thermal sleeve around the opening 60 and at the other end are received into an annular groove 66 machined in the cladding 64 that lines the surface of a nozzle 24 .
The lower end of the thermal sleeve includes axially extending slots 68 . Small keys 70 , machined in the bore of the nozzle 24 , are received in the slots 68 , to maintain centering of the thermal sleeve lower end during transient conditions.
Flow in the crevice region 72 behind the thermal sleeve 26 is restricted by small clearances between the sleeve and the nozzle bore at both the upper end raised cladding surface and at the lower end. Thus, an improved thermal sleeve attachment to the interior surface of the nozzle is provided that can accommodate thermal growth without adding substantial stress to the nozzle.
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular embodiments disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof.
|
A thermal sleeve is mechanically attached to the bore of a surge nozzle of a pressurizer for the primary circuit of a pressurized water reactor steam generating system. The thermal sleeve is attached with a series of keys and slots which maintain the thermal sleeve centered in the nozzle while permitting thermal growth and restricting flow between the sleeve and the interior wall of the nozzle.
| 5
|
FIELD OF THE INVENTION
[0001] The present invention generally relates to application of microbe carrier in treating fluid, and particularly to apparatus including microbe carriers for treating drain water or waste liquid.
BACKGROUND OF THE INVENTION
[0002] In conventional processes of using microbes to treat drain water, there is difficulty keeping microbes effectually reside in drain water. Although application of porous microbe carrier may extend the time period for microbes to reside in drain water, there is inconvenience and/or economical disadvantage associated with the procedures and implementations as well as maintenance thereof. It is extremely difficult to have a large mass of microbe carriers evenly dispersed in the drain water to be treated, and it is even unrealistic or impractical to control the location of each of the microbe carriers or the distribution of the large mass of microbe carriers in a realizable and economic way. For example, a large mass of microbe carriers poured into or sprinkled onto the drain water will always accumulate on the bottom of the storage facilities accommodating the drain water, or on the location through which the drain water flows out of the storage facilities in case there is need of in-and-out flowing of the drain water. The mass of microbe carriers, unevenly dispersed, always tend to excessively accumulate on one or few positions in the storage facilities, with biofilms of the microbes forming a hindrance to the flowing of water, and lowering the efficiency of treating the drain water. Even if the mass of biofilms of the microbes may be cleaned by applying inversely flowing water to the microbe carriers, the scheme is feasible only for a temporary purpose, and far away from providing a permanent or an ideal solution, not to mention the significant cost (temporary treatment process delay and need of extra labor as well as extra facilities) arising therefrom. It can thus be seen that the best solution to the problem is to have the mass of microbe carriers evenly dispersed or controlled to evenly spread in the drain water to be treated, thereby any undesired accumulation of the microbe carriers can be prevented or easily amended.
[0003] In conventional processes of using microbe carriers (such as Plastic Pall Rings, Activated Carbon, Filter Media or Contact Filter in Bio-Filtration) to treat drain water, microbe carriers are usually fixed in stationary states or placed in floating states. The microbe carriers, fixed in stationary states, always constitute significant resistance to the flowing of water, resulting in warp or cracking of the microbe carriers, lowering treatment efficacy and capacity. The microbe carriers placed in flowing states often collide with each other and have the biofilms thereof dropped away, resulting in significant reduction of treatment capability.
[0004] Similarly, in conventional processes of using particles to treat drain water, particles are also usually fixed in stationary states or placed in floating states, resulting in the same problem. FIGS. 13 and 14 (FIGS. 1 and 2 of U.S. Pat. No. 6,420,292) show some conventional examples of using particles to treat drain water, where drain water 4 (or another type of drain liquid) to be treated flows toward surfaces 1 of ceramic articles which were placed for the purpose of cleaning the drain water, and passes pores 2 to contact crystalline particles 3 . FIG. 15 (FIG. 3 of U.S. Pat. No. 6,420,292) shows another conventional example of using particles to treat drain water, where drain water 4 (or another type of drain liquid) to be treated flows through three columns 6 connected in series and containing mixture 7 of porous ceramics therein for the purpose of cleaning the drain water. These conventional modes of using particles to treat drain water suffer the same problem.
[0005] It is thus seen that the application of either microbes or particles to the treatment of drain water (or another type of drain liquid) suffers problems to be solved and deserves improvement. Related industries have long been expecting better schemes for applying microbes to the treatment of drain water (or another type of drain liquid), by which need of alternation of facilities and need of inverse flowing process of cleaning can be eliminated, and simplification as well as convenience in treating drain fluid can be achieved. The present invention is therefore developed not only to provide solutions to the problems having long been faced by related industries, but also to further promote the efficiency and convenience in treating drain water or any fluid.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide an apparatus for related industries to apply microbes to the treatment of drain water (or another type of fluid).
[0007] It is another object of the present invention to provide an apparatus for related industries to reduce the cost of applying microbes to the treatment of drain water
[0008] It is a further object of the present invention to provide an apparatus for related industries to control the locations and distributions of microbe carriers in the drain water to be treated, for achieving better efficacy in treating drain water.
[0009] It is a object of the present invention to provide an apparatus for related industries to apply microbes to the treatment of drain water
[0010] It is another further object of the present invention to provide an apparatus for related industries to apply microbes to the treatment of drain water, by which microbe carriers can be conveniently replaced or supplemented or cleaned in an economic way.
[0011] It is furthermore another object of the present invention to provide an apparatus for related industries to apply microbes to the treatment of drain water, with which the storage facilities accommodating drain water can be conveniently and economically cleaned and subjected to maintenance.
[0012] One of the features of the present invention is that each module which contains some microbe carriers is used as an application or installation or operation or maintenance unit in treating drain water (or another type of fluid), and a plurality of the modules can be so fixed or supported to evenly disperse in the drain water to be treated, either in steady states or in states of moving in a certain region (a restricted region for example), thereby each of modules can be individually cleaned or replaced or relocated or subjected to maintenance.
[0013] One of the merits of the present invention is that a large mass of microbe carriers are distributed to a plurality of modules each can be used as an application or installation or operation or maintenance unit in treating drain water (or another type of fluid), not only for each of the modules to be individually used or installed or operated or subjected to maintenance, but also for any combination of the modules to be used or installed or operated or subjected to maintenance.
[0014] Another one of the merits of the present invention is that it is easy to adapt the installation, operation, and maintenance of microbe carriers to application environment/conditions and/or demands, as a result of the availability of application or installation or operation or maintenance units each containing only part of a large mass of microbe carriers.
[0015] A further one of the merits of the present invention is the significant promotion of efficacy and efficiency in treating drain water (or any fluid), resulting from easy control of the locations and/or distributions of a large mass of microbe carriers in application environment (inside of the drain water to be treated or on the surface surrounding the drain water to be treated, for example), because of the availability of installation or operation or maintenance units each containing only part of a large mass of microbe carriers.
[0016] Another further one of the merits of the present invention is the lower application cost and/or better immunization capability of microbe carriers against environmental influence, as a result of the convenience and simplification in acquiring, transporting, storing, inspecting, and auditing a large mass of microbe carriers, because of the availability of installation or operation or maintenance units each containing only part of a large mass of microbe carriers.
[0017] The other objects, features, and merits of the present invention may be comprehended from the following description with reference to drawings.
INTRODUCTION TO THE INVENTION
[0018] One aspect of the present invention is an apparatus for treating a fluid, which comprises: at least a microbe carrier; and a container accommodating the microbe carrier, and including a restriction structure and a fluid passage structure, wherein the restriction structure is for restricting the moving of the microbe carrier so that the microbe carrier is either stationary or movable in a restricted region, the fluid passage structure provides a flow passage between the interior of the container and the exterior of the container, i.e., the fluid passage structure allows the fluid outside the container to flow into the container, and/or the fluid inside the container to flow out of the container, and/or the fluid passage structure allows the fluid to flow through the interior of the container (from one side of the container to another side of the container, for example). The fluid passage structure, for example, is such that the flow passage provided thereby includes at least one gap for the fluid to pass and contact at least part of the microbe carrier. The restriction structure, for example, is such that the microbe carrier is surrounded by at least part of it, and/or the gap is surrounded by part of it.
[0019] To provide better environment for microbes to reside and/or to be more effective, the microbe carrier according to the present invention, preferably, includes a plurality of holes.
[0020] The container according to the present invention, preferably further includes a force interface structure for receiving an external force applied thereto for controlling the location of the container and/or the moving of the container. Also preferably, the container further includes: a supporting interface structure for contacting an external object which is to support the container; and/or a connection interface structure for connecting the container and an external object to maintain a space between the container and the external object, or for connecting adjacent ones of the containers to maintain a space between the adjacent containers. The container may even further include: an entrance through which the microbe carrier is placed in the container, wherein an entrance-only structure is used for preventing the microbe carrier from moving to the outside of the container; and a lock structure controllable to be in one of two states, one allowing the microbe carrier to move outward from the container, the other preventing the microbe carrier from moving outward from the container.
[0021] The apparatus according to the present invention, preferably further comprises a supporter for supporting the container in such a way (in an adequate position, for example) that at least part of the microbe carrier therein contacts the fluid, or at least part of the container is submerged in the fluid. The supporter preferably includes a fixing portion and a connecting portion, the fixing portion being fixed by earth (ground, for example), the connecting portion for connecting the fixing portion and the container. The connecting portion may be a hardware by which the supporter supports the container in such a way that the container is fixed at a location or in a steady state. The connecting portion may otherwise be a software by which the supporter supports the container in such a way that the container moves in a restricted region. For example, the connecting portion may be a soft cord coupled, via the fixing portion (a fixing device, for example), onto a building or the facilities accommodating the fluid to be treated, or onto any external object.
[0022] Alternatively, the apparatus according to the present invention further comprises a swing driver for driving the container to swing, or a motion driver for driving the container to move, preferably, to move in a certain or restricted region.
[0023] The apparatus according to the present invention may further comprise a fluid-accommodation structure for accommodating the fluid to be treated, wherein the supporter is fixed onto the fluid-accommodation structure. For example, the supporter has a connecting portion thereof coupled or fixed, through a fixing portion thereof, onto the fluid-accommodation structure.
[0024] Another aspect of the present invention is an apparatus for treating a fluid which resides or is accommodated in a region surrounded by a fluid-accommodation structure. The apparatus comprises: at least a microbe carrier; a restriction structure for restricting the moving of the microbe carrier; and a supporter for supporting the restriction structure in such a way that at least part of the microbe carrier contacts the fluid. The restriction structure here, for example, is in the shape of a net enclosing the microbe carrier, thereby provides (or includes) a flow passage allowing fluid to flow therethrough while prevents the microbe carrier from moving therethrough. The flow passage includes a plurality of gaps through which at least part of the microbe carrier is contacted by the fluid. Furthermore, the restriction structure here is so configured as to separate a large mass of microbe carriers into a plurality of portions respectively residing in different regions, each of the portions movable only in one of the regions. The supporter here may include a fixing portion and a connecting portion, the fixing portion being coupled with (or fixed onto) the fluid-accommodation structure or earth or an external object (a building, for example) other than earth and the fluid-accommodation structure, the connecting portion for connecting the fixing portion and the restriction structure. For example, the fixing portion is a hardware bar or connected with the fluid-accommodation structure, the connecting portion is a software or hardware material connecting the fixing portion and the restriction structure. Alternatively the fixing portion may be a component for fixing one end of the connecting portion (a bar or a cord) onto the fluid-accommodation structure or a building.
[0025] To maintain a better efficacy in treating the fluid surrounded by the fluid-accommodation structure fluid, the apparatus here preferably includes a space-maintaining structure for maintaining a space between the microbe carrier and the fluid-accommodation structure, or maintaining a space between two portions (particularly adjacent ones) of the mass of microbe carriers used in treating the fluid. For example, the space-maintaining structure is a bar between the restriction structure and the fluid-accommodation structure, or a bar between different parts of the restriction structure wherein different parts of the restriction structure restrict the moving of different portions of the mass of microbe carriers used to treat the fluid.
[0026] A further aspect of the present invention is a method for treating a fluid. The method comprises: accommodating at least a microbe carrier by a container, the container restricting the moving of the microbe carrier and allowing the fluid to flow between the interior thereof and the exterior thereof; and supporting the container in such a way that at least part of the microbe carrier contacts the fluid.
[0027] The present invention may best be understood through the following description with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIGS. 1-4 show embodiments of apparatus provided according to the present invention.
[0029] FIG. 5 shows a top view of an embodiment of the apparatus shown in FIGS. 1-2 .
[0030] FIG. 6 shows an embodiment of connecting a plurality of the apparatus shown in FIGS. 1-5 .
[0031] FIGS. 7-8 show another embodiments of apparatus provided according to the present invention.
[0032] FIGS. 9-10 show another further embodiments of apparatus provided according to the present invention and based on the embodiments represented by FIGS. 1-5 or FIG. 6 or FIGS. 7-8 .
[0033] FIG. 11 is a side view of the apparatus shown in FIG. 10 .
[0034] FIGS. 12 a - 12 b show a still further embodiment of apparatus provided according to the present invention and based on the embodiments represented by FIGS. 1-5 or FIG. 6 or FIGS. 7-8 .
[0035] FIGS. 13-14 show prior arts (FIGS. 1 and 2 of U.S. Pat. No. 6,420,292).
[0036] FIG. 15 shows a prior art (FIG. 3 of U.S. Pat. No. 6,420,292).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Embodiments of the apparatus provided according to the present invention for treating a fluid are now illustrated by referring to the side views shown in FIGS. 1, 2 , 3 , and 4 , and the top view shown in FIG. 5 . In FIGS. 1, 2 , 3 , 4 , and 5 , at least a microbe carrier 15 is accommodated in a container 11 , container 11 includes a restriction structure composed of (or represented by) plural bars 12 and 13 , container 11 also includes a fluid passage structure composed of (or represented by) a plurality of gaps 14 which are defined (or surrounded) by bars 12 and 13 , the restriction structure composed of plural bars 12 and 13 is for restricting the moving of the microbe carrier 15 so that the microbe carrier 15 is either stationary or movable in a restricted region such as the interior of container 11 , the fluid passage structure represented by the plurality of gaps 14 provides a flow passage between the interior of the container 11 and the exterior of the container 11 , i.e., the fluid passage structure represented by the plurality of gaps 14 allows the fluid (not shown in FIG. 1 ) outside the container 11 to flow into the container 11 , and/or the fluid inside the container 11 to flow out of the container 11 , and/or the fluid passage structure represented by the plurality of gaps 14 allows the fluid to flow through the interior of the container 11 (from one side of the container 11 to another side of the container 11 , for example). The fluid passage structure represented by the plurality of gaps 14 , obviously, allows fluid to pass and contact part or the whole of microbe carrier 15 . The restriction structure composed of plural bars 12 and 13 , for example, is in the shape of a net enclosing the interior of container 11 , and defining the plurality of gaps 14 , wherein each of the gaps 14 is such that microbe carrier 15 cannot pass therethrough to move out of container 11 . Gap 14 , for example, may have size smaller than microbe carrier 15 or be so shaped as to prevent microbe carrier 15 from passing therethrough.
[0038] To provide better environment for microbes to reside and/or to be more effective, the microbe carrier 15 according to the present invention, preferably, includes a plurality of holes 16 .
[0039] The container 11 according to the present invention, preferably further includes a force interface structure 17 (in FIGS. 3 and 4 ) for receiving an external force applied thereto for controlling the location of the container 11 and/or the moving of the container 11 . Also preferably, the container 11 further includes: a supporting interface structure 19 (in FIGS. 3 and 4 ) for contacting an external object (such as a bar 82 fixed via bar 81 onto a fluid-accommodation structure 8 in FIG. 10 ) which is to support the container 11 ; and/or a lock structure 20 (in FIGS. 2 and 3 ) which is controllable to be in one of two states, one allowing the restriction structure (composed of plural bars 12 and 13 ) to be separated into two parts for microbe carrier 15 to move outward from (and/or inward to) the container 11 , the other keeping the restriction structure (composed of plural bars 12 and 13 ) to enclose the interior of container 11 thereby preventing the microbe carrier 15 from moving outward from the container 11 . Lock structure 20 may be replaced by an entrance (not shown in figures) through which the microbe carrier 15 is placed in the container 11 , wherein an entrance-only structure (not shown in figures) is used for preventing the microbe carrier 15 from moving to the outside of the container 11 through the entrance. The entrance-only structure, for example, may include at least a bendable (or flexible) and thin object having one end fixed on the edge of the entrance, and having another end movable and pointing to the interior of container 11 to allow microbe carrier 15 to move from the exterior of container 11 to the interior of container 11 , but prevent microbe carrier 15 from moving out of the interior of container 11 . Either the force interface structure 17 or supporting interface structure 19 can also be used as a connection interface structure for connecting the container 11 and an external object (such as the fluid-accommodation structure 8 shown in FIG. 9 or objects 81 and 82 fixed onto the fluid-accommodation structure 8 shown in FIG. 10 ) to maintain a space between the container 11 and the external object, or for connecting a space-maintaining structure 32 (in FIG. 6 ) between adjacent ones of a plurality of containers 11 to maintain a space between the adjacent containers 11 . Space-maintaining structure 32 in FIG. 6 may also be used to connect container 11 and an external object (not shown in figures).
[0040] The apparatus according to the present invention, preferably further comprises a supporter 33 (in FIG. 6 ) for supporting the container 11 in such a way (in an adequate position, for example) that at least part of the microbe carrier 15 in container 11 contacts the fluid (not shown in figures), or at least part of the container 11 is submerged in the fluid (not shown in figures). The supporter 33 preferably includes a fixing portion 34 and a connecting portion 35 , the fixing portion 34 being fixed onto earth (not shown in figures) or an external object such as a building (not shown in figures) or a fluid-accommodation structure accommodating the fluid to be treated, the connecting portion 35 for connecting the fixing portion 34 and the container 11 . The connecting portion 35 may be a hardware by which the supporter 33 supports the container 11 in such a way that the container 11 is fixed at a location (not shown in figures) or in a steady state. The connecting portion 35 may otherwise be a software by which the supporter 33 supports the container 11 in such a way that the container 11 is movable in a restricted region (not shown in figures). For example, the connecting portion 35 may be a soft cord coupled, via fixing portion 34 , onto a building (not shown in figures) or the facilities (not shown in figures) accommodating the fluid to be treated, or onto any external object. Fixing portion 34 is not always necessary for coupling connecting portion 35 onto an external object. Connecting portion 35 may be directly coupled onto an external object such as a building or the facilities (not shown in figures) accommodating the fluid to be treated. Alternatively the fixing portion may be just a component for fixing one end of the connecting portion (a bar or a cord) onto the fluid-accommodation structure or a building, thereby another end of the connecting portion moves or swings with containers 11 connected thereto. Another embodiments of the apparatus provided according to the present invention are represented by FIGS. 7 and 8 . In FIG. 7 , the apparatus 70 provided according to the present invention includes: a restriction structure defining a plurality of gaps 74 and being composed of plural bars 72 and 73 ; a plurality of microbe carriers 15 enclosed by the restriction structure; and a supporter 71 for supporting the apparatus 70 . The apparatus provided according to the present invention and represented by FIG. 7 preferably further includes a structure 79 (in FIG. 8 ) which can be used as a force interface structure or a supporting interface structure or a connection interface structure. The structure 79 , for example, may be used to connect apparatus 70 and an external object (not shown in figures), for maintaining a space between apparatus 70 and the external object. As a plurality of apparatus 70 are often used to treat a fluid accommodated in the same facilities, structure 79 may also be used to directly connect two adjacent apparatus 70 or connect two adjacent apparatus 70 via a space-maintaining structure (corresponding to the space-maintaining structure 32 shown in FIG. 6 ), for maintaining a space between two adjacent apparatus 70 .
[0041] An application of the apparatus 70 (shown in FIGS. 7 and 8 ) to the treatment of a fluid is that a plurality of the apparatus 70 are placed in a fluid-accommodation structure (such as the one indicated by 8 in FIGS. 9 , and 10 ), with structure 79 connected to the fluid-accommodation structure directly or via a space-maintaining structure or via a supporter (corresponding to the supporter composed of objects 81 and 82 shown in FIGS. 10 and 11 ). Supporter 71 (shown in FIG. 7 ) may be between apparatus 70 and the bottom of the fluid-accommodation structure to support apparatus 70 . Alternatively another object such as the supporter (shown in FIG. 10 ) composed of objects 81 and 82 and fixed onto the fluid-accommodation structure may be used to support apparatus 70 in such a way that apparatus 70 is in a steady position or moves in a restricted region, with microbe carriers 15 enclosed therein contacting the fluid to be treated.
[0042] FIGS. 9 , and 10 show an apparatus provided according to the present invention for treating a fluid, which comprises: a fluid-accommodation structure 8 for accommodating the fluid (not shown in figures) to be treated; a plurality of containers 11 accommodating microbe carriers 15 (not shown in FIGS. 9 and 10 , but shown in FIGS. 1, 2 , 6 , and 7 ) and being installed in the fluid-accommodation structure 8 ; and a supporter composed of objects 81 and 82 , for supporting containers 11 , with object 81 fixed onto the fluid-accommodation structure 8 , with object 82 connecting object 81 and a series of containers 11 . FIG. 11 is a side view of the apparatus shown in FIG. 10 . In FIG. 10 , for example, object 81 of the supporter is used as a fixing portion coupled or fixed onto the fluid-accommodation structure 8 , and object 82 of the supporter is used as a connecting portion coupled to the fixing portion (object 81 ) to support a series of containers 11 . All the microbe carriers accommodated in containers 11 , preferably, have at least part thereof contacting the fluid (not shown in figures) which is to be treated and which is in the region surrounded or defined by the fluid-accommodation structure 8 .
[0043] The object 82 in FIG. 10 may be a hardware by which the supporter composed of objects 81 and 82 supports the container 11 in such a way that the container 11 is fixed at a location (not shown in figures) or in a steady state. The object 82 may otherwise be a software by which the supporter composed of objects 81 and 82 supports the container 11 in such a way that the container 11 is movable in a restricted region (not shown in figures).
[0044] Another further embodiment of an apparatus provided according to the present invention is shown in FIGS. 12 a (side view) and 12 b (top view). In FIG. 12 a, a fluid-accommodation structure 8 is used to accommodate a fluid (not shown in figures) to be treated, a plurality of containers 11 are supported by a supporter composed of connecting portions 82 and a fixing portion 81 , the plurality of containers 11 are separated into many groups each with containers 11 therein connected and spaced by a space-maintaining structure 83 , each container 11 has at least a microbe carrier 15 therein, fixing portion 81 is coupled to a motion or swing driver 84 composed of a motor 85 (or any motion power producer), a motion transmitter 86 , and a motion transmission interface 90 . Containers 11 move or swing in response to the operation of driver 84 . An example of driving containers 11 to swing up and down is indicated by arrows 88 (upward) and 89 (downward) in FIG. 12 a, another example of driving containers 11 to move is indicated by an arrow 87 (rotate around the center of fluid-accommodation structure 8 seen from the top of fluid-accommodation structure 8 ) in FIG. 12 b. Obviously containers 11 may also be driven to rotate in an inverse direction, or to swing in clockwise and counter clockwise directions seen from the top of fluid-accommodation structure 8 . The apparatus is preferably such that each of the containers 11 installed in fluid-accommodation structure 8 has the microbe carrier therein contacted by the fluid (not shown in figures) accommodated in fluid-accommodation structure 8 .
[0045] Still another further embodiment of the present invention is a method for treating a fluid, which comprises: accommodating at least a microbe carrier 15 by a container ( 11 in FIGS. 1 and 2 , or apparatus 70 in FIGS. 7 and 8 ), the container restricting the moving of the microbe carrier 15 and allowing the fluid (not shown in figures) to flow between the interior thereof and the exterior thereof; and supporting the container ( 11 in FIGS. 1 and 2 , or 70 in FIGS. 7 and 8 ) in such a way that at least part of the microbe carrier 15 accommodated by container 11 contacts the fluid.
[0046] While the invention has been described in terms of what are presently considered to be the most practical and preferred embodiments, it shall be understood that the invention is not limited to the disclosed embodiment. On the contrary, any modifications or similar arrangements shall be deemed covered by the spirit of the present invention.
|
An art of applying microbes to the treatment of a fluid is provided. The feature is that a large mass of microbe carriers are distributed to a plurality of containers each including a restriction structure and a fluid passage structure, wherein the restriction structure restricts the moving of the microbe carrier so that the microbe carrier is either stationary or movable in a restricted region, and the fluid passage structure provides the fluid with a flow passage between the interior and the exterior of the container so that the microbe carrier in the container contacts the fluid. Various applications based on the containers or the like are also disclosed.
| 2
|
RELATED APPLICATIONS
[0001] This Application claims rights under 35 USC §119(e) from U.S. Patent Application Ser. No. 60/645,079 filed Jan. 20, 2005; U.S. Patent Application Ser. No. 60/645,221 filed Jan. 20, 2005; U.S. Patent Application Ser. No. 60/645,222 filed Jan. 20, 2005; U.S. Patent Application Ser. No. 60/645,223 filed Jan. 20, 2005; U.S. Patent Application Ser. No. 60/645,224 filed Jan. 20, 2005; U.S. Patent Application Ser. No. 60/645,226 filed Jan. 20, 2005; and U.S. Patent Application Ser. No. 60/645,227 filed Jan. 20, 2005. This Application may also be considered to be related to U.S. Application Ser. No. 60/711,217 filed Aug. 25, 2005; U.S. Application 60/711,314 filed Aug. 25, 2005; U.S. Application 60/711,218 filed Aug. 25, 2005; U.S. Application 60/711,325 filed Aug. 25, 2005; U.S. Application 60/722,309 filed Sep. 30, 2005; U.S. Application 60/726,145 filed Oct. 13, 2005; and U.S. Application 60/726,146 filed Oct. 13. 2005
FIELD OF THE INVENTION
[0002] This invention relates to microradios and more particularly to the design, manufacture and use of microradios.
BACKGROUND OF THE INVENTION
[0003] The size of radios, meaning combined transmitters and receivers, has been steadily decreasing so that their use, for instance, in RF tags is now commonplace. It will be appreciated that each RF tag has a single small or miniature radio that in general costs approximately 50 cents. All of these RF tags are meant to be used to tag items and to be able to detect the items when they pass through a checkpoint. The costs of such tags and applications for even smaller tags give rise to the possibility of a large number of applications should, for instance, the radios be implementable well below a cubic millimeter in size and more particularly down to a 10-micron cube.
[0004] Moreover, the power output of such single microradios leaves something to be desired inasmuch as single microradios are limited in output power, especially when using parasitic powering schemes. Moreover, in order to parasitically power such miniature radios one needs supercapacitor technology involving high energy density capacitors fabricated in a regular pattern with a large surface area per volume.
[0005] It will be appreciated that if the microradio needs to have a given power output to obtain a given range, then the range is severely limited both by the ability to provide supercapacitors or, if a battery is carried on board, then the size of the miniature radio is prohibitively large.
[0006] Were it possible to make large numbers of microradios in the 10-micron size range and were it possible to distribute these radios across an area; and further if the radios could be accessed so as to provide their outputs in a coherent fashion, then the distributing of these radios over a given area would have an n 2 power advantage such that if it were possible to manufacture, code and distribute 1,000 radios in a given area, one would have a million more times the radiated power.
[0007] By causing each of the radios to coherently radiate, one can increase range or concurrently decrease the need for tuning each of the radios to their antennas. There is therefore a benefit in providing an ensemble of a large number of miniature radios from the point of view of, for instance, being able to detect the radios at 10,000 kilometers or better, such as by satellite.
[0008] The ability to produce hundreds of thousands or millions of radios at a time not only is important to reduce the cost of the radios from, for instance, 50 cents per radio to $1.00 per million radios, it is also important that one be able to utilize non-high density capacitors that presently exist in order to power the miniature radios parasitically. Because batteries cannot be made sufficiently small, one requires that a microradio be powered parasitically, meaning that energy that is available from the environment is captured on a capacitor, where it is rectified and utilized to power the transceiver.
[0009] Thus it would be desirable to provide a parasitically powered microradio, parasitically coupled to some decent antenna, with the microradio having its own microantenna.
[0010] Even in the case that each radio is not particularly well-tuned to whatever antenna it is using, the ability to produce large numbers of extremely inexpensive microradios and randomly distribute them across a surface that could function as an antenna could result in at least a large portion of the miniature radios being located at the feedpoint of whatever antenna is available. Thus, if one can distribute the radios across a surface in some random fashion, then the probability of there being a microradio at an antenna feedpoint is large for at least a certain percentage of the distributed radios.
[0011] Thus if it were possible to manufacture millions of microradios inexpensively and distribute them across a surface, and assuming the surface had some natural antenna such as a slot in a metal object, or the dielectric as provided by the human or an animal body and the salt therein, or a ferromagnetic body, then one could obtain a sufficiently usable signal that could be detected anywhere from numbers of feet to many thousands of kilometers away, even with the minute power outputs from each of the individual microradios.
[0012] As a further consideration of power it will be appreciated that if the transmit cycle for the radio could be reduced to a small portion of a prolonged charging cycle, then it would be possible to deploy such numbers of microradios without concern about power. This is due to the relatively long charging time available for the capacitors utilized for each of the microradios versus the short amount of time necessary to transmit information.
[0013] Moreover, were it possible to reliably manufacture such microradios on a very large scale, there are applications in tagging and authentication as well as anti-piracy and medical applications for which such tiny microradios or ensembles of microradios could be used.
SUMMARY OF INVENTION
[0014] In the subject invention, there are improvements to the microradios and antennas themselves, a method of manufacture, systems for improving parasitic powering and transmitter range, providing ensembles of microradios, deployment of the ensembles in paints or other coatings containing microradios, aerosol sprays and liquid carriers, and a number of applications for such radios.
[0015] As will be discussed, the subject invention involves improvements that enhance the parasitic powering of the microradios so that they can be powered by low-level ambient radiation or by direct radiation. This involves a powering/transmit cycle in which the power accumulates on a capacitor over a long period of time and is then read out to an oscillator just sufficient to sustain a brief modulated burst. This is unlike the RFID tags that act as smart retro-reflectors, which do not transmit stored parasitically developed energy but rather immediately use the power from incident radiation. What the subject parasitic powering process does is to store energy derived from the environment. This permits separating the reader from the power source and gives rise to applications in which energy in the ambient can be used to power a microradio. In this scenario, energy collected over time on a capacitor is used to power the microradio to occasionally put out a signal burst that can be detected from a position removed from the parasitic source of power, such as by an overflying aircraft or satellite.
[0016] This powering scheme in which power is built up and stored on a capacitor utilizes a hysteretic switch that permits the microradio to absorb ambient radiation over a long period of time until such time as a capacitor is sufficiently charged, after which the power from the capacitor is coupled to the oscillator that emits a signal burst. For the purposes of this invention a “hysteretic switch” is a switch that allows conduction of electrical current when a threshold voltage is reached and which continues to allow conduction of electrical current until a second lower threshold voltage is reached, at which time conduction ceases. One simple example of a hysteretic switch is a transistor that is forced into conduction when the capacitor voltage reaches some predetermined level. Thereafter the capacitor is coupled to the oscillator of the microradio for the signal burst. In this case the oscillator is automatically and cyclically fired off. Because the exact timing of the signal blast is not important in most cases, it is acceptable to signal only occasionally.
[0017] Since the detector or reader is separate from the power source, which in this case is the ambient, one could surveil an area at a distance by flying over it and detecting the information occasionally transmitted by the microradio.
[0018] Thus, rather than utilizing an RFID tag smart reflector that is able to modulate its reflection, the subject hysteretic switch microradio offers considerable flexibility in its use and makes it possible for very low ambient power to charge the microradio capacitor. When the microradio has enough energy it can be automatically fired off to deliver a relatively large amount of power that can be detected by a distant collector, unlike short-range RFID tags.
[0019] Moreover, it is part of the subject invention that it has been found that there is enough RF energy in the ambient to charge a microradio when operated in this regime, whether the ambient contains ambient RF energy or ambient light.
[0020] Secondly, the subject microradios can be made particle sized and extremely inexpensively so that massive numbers can be distributed over a surface that either has some natural radiative structure or includes an antenna with a feedpoint. In the case of a naturally radiative structure such as a metal surface with a slot or even a dielectric composed of animal tissue, dispersing a large number of microradios on the structure results in at least some of the microradios being optimally located relative to the naturally radiating surface. In one embodiment this means that some of the microradios will be located at the feedpoints of what could constitute antennas of the naturally radiating structure. The random distribution of the microradios across the structure thus provides that at least some of the radios will optimally couple ambient power to the microradio as well as providing an optimal coupling of output power from the microradio to the ambient. Thus capacitor charging and radiating power are maximized by providing an ensemble of microradios.
[0021] By random microradio positioning, one has a faster charging time and a longer range for at least some of the microradios. This is because a random distribution optimally places some microradios at an antenna feedpoint.
[0022] Moreover, when the radios are strobed so as to cause a coherent response, the output power is increased by n 2 , such that even if powered by the ambient, the radios can be heard from as far away as 10,000 kilometers, e.g., satellites.
[0023] As another feature of the subject invention, the dispersing of the radios in the vicinity of the feedpoint of an already-existing antenna makes unnecessary the previously critical, costly placement of the microradio at the antenna.
[0024] Additionally, with the use of the subject charging/transmission cycles and the use of multiple particle-like microradios one can avoid the requirement for supercapacitors to increase power and range.
[0025] In short, one can provide RFID tags without the expense of accurately placing a circuit on an antenna. Moreover, one can provide an RFID tag at 1/50 th the cost, with better range and better charging.
[0026] As part of the subject invention, one can manufacture the microradio particles utilizing standard semiconductor processing techniques, in which the microradios can be patterned on a wafer, diced and distributed in a liquid or aerosol spray, or by dispersing, suspending or entraining the microradios in a suitable paint or other coating.
[0027] Additionally, the subject invention includes the option of providing specialized antennas, including microscopic dipoles, microcoils, and magnetic dipoles that can be fabricated in sizes commensurate with the size of the microradio itself.
[0028] Furthermore, since all of the microradios use rectifiers and since the rectifiers have diodes with input voltage thresholds, it has been found that providing active radiation at different frequencies results in a combined voltage output exceeding critical diode voltage thresholds. This further increases the ability to power the microradios with low ambient energy. Of course, all of the above techniques for more effectively coupling ambient energy into the microradios help to overcome the diode voltage thresholds.
[0029] Moreover, with the above-mentioned coherent operation of the microradios, the n 2 power increase results in extremely long-range detectability.
[0030] In summary, such flexibility permits the use of even crude, inefficient microradios in a large number of applications, including RFID tags, location detection, authentication, remote sensing of large areas for, for instance, crop health and the presence of hazardous chemicals or metallic objects, as well as applications involving sensing fluid flow parameters in both large pipes and in blood vessels, with medical applications including drug delivery through the activation of a microradio, for instance attached to a molecular tag, with the microradio being powered by ambient or directed radiation.
[0031] More specifically, the subject microradios are provided with capacitor leak protection afforded by the hysteresis switch, so that they can be charged up to store energy for release later in a burst. Specialized antennas can be used or natural radiative structures are available, such as naturally occurring slot antennas; or human or animal tissue provides a dielectric radiative structure that contain enough salt to provide the dielectric with requisite conductivity.
[0032] Secondly, the subject invention includes deploying large numbers of crude, inexpensive microradios over a given area. With large numbers of radios, although randomly distributed over a structure, there will be radios at favorable locations, in one embodiment at or close to an antenna feedpoint.
[0033] Moreover, ensembles of such radios can be used for a wide variety of purposes such as for authentication, identification, tracking and even for biomedical purposes such as biologic parameter sensing and drug delivery.
[0034] Importantly, the microradios can be manufactured in a high-density process on large wafers, after which they are separated into millions of 10-micron particles, each serving as a microradio. These particle microradios can be programmed en masse and can be made to coherently radiate to provide an n 2 power boost that can extend the range of the microradios up to 10,000 kilometers.
[0035] Most importantly, the cost of a million microradios manufactured as discussed above can be brought down to a dollar or less so that providing massive numbers of such radios is much less costly than using a single microradio.
[0036] Thus the ability to provide improved microradios in a high-yield process permits applications as diverse as spraying a field for crop health information, or an area to detect a wide variety of terrorist threats. Both consumer and commercial parts of any kind can be sprayed with paint or other coating containing microradios for anti-piracy purposes, as well as to provide for a much more cost effective RFID. Moreover, tracking and other functions are made feasible and inexpensive with the use of the ensemble of microradios provided by the subject technology.
[0037] As will be appreciated, in the subject invention a parasitically powered microradio is fabricated on a standard wafer, is cut and is made available for deployment either in an aerosol, in a paint or other coating containing microradios, or in some liquid dispersion such that the microradios can be distributed over a surface of interest, be it an electronic or mechanical part, a field or other terrain; or in or on containers to track and count inventories, and for authentication purposes.
[0038] While some portions of each microradio may involve nanostructures such as nanotube resonators or even carbon nanotube electronics, the subject invention is not limited to nanotechnology. Nor is it limited to a particular high energy density capacitor technology.
[0039] The only requirement is that the microradio be parasitically powered. Thus it is the intent of the subject invention that one manufacture a small circuit that is parasitically coupled to its environment.
[0040] In summary, a microradio is provided with a hysteretic switch to permit an optimum range increasing charging cycle, with the charging cycle being long relative to the transmit cycle. Secondly, an ensemble of microradios permits an n 2 power enhancement to increase range with coherent operation. Various multi-frequency techniques are used both for parasitic powering and to isolate powering and transmit cycles. Applications for microradios and specifically for ensembles of microradios include authentication, tracking, fluid flow sensing, identification, terrain surveillance including crop health sensing and detection of improvised explosive devices, biohazard and containment breach detection, and biomedical applications including the use of microradios attached to molecular tags to destroy tagged cells when the microradios are activated. Microradio deployment includes the use of suitable paints or other coatings, greases and aerosols. Moreover, specialized antennas, including microcoils, mini dipoles, and staircase coiled structures are disclosed, with the use of nano-devices further reducing the size of the microradios.
[0041] For the purposes of this invention the term “microradio” means a radio having nano-size elements or dimensions up to a dimension of about 4 mm×4 mm.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] These and other features of the subject invention will be better understood in connection with the Detailed Description, in conjunction with the Drawings, of which:
[0043] FIG. 1 is a block diagram showing the subject microradio, which includes a rectifier, a hysteretic switch and an oscillator, coupled to a naturally radiative structure such that the microradio may be powered parasitically and transmit its information back through the naturally radiative structure;
[0044] FIG. 2 is a block diagram illustrating the microradio of FIG. 1 , rather than coupled to a naturally radiative structure, coupled to an antenna for improvement of the parasitic powering and the range of the microradio;
[0045] FIG. 3 is a diagrammatic illustration of a miniaturized dipole coupled to the microradio of FIG. 1 or 2 , showing that the length of the portions of the dipole are commensurate with the size of the microradio;
[0046] FIG. 4 is a diagrammatic illustration of a microcoil antenna for use with the microradio of FIG. 2 ;
[0047] FIG. 5 is a diagrammatic illustration of a staircase antenna having a number of turns about a high-μ core to provide a low profile antenna for use in the microradio of FIG. 2 ;
[0048] FIG. 6A is a block diagram of a microradio that includes both a modulated oscillator and a receiver section detecting command signals and for causing power to be applied to the oscillator after receipt of a command signal;
[0049] FIG. 6B is a graph showing the timeline for use in parasitically powering the microradio of FIGS. 1 and 2 , indicating a relatively long charge time of about 1 second to impart about 1 microjoule to the receiver of the microradio, which listens for approximately 1 millisecond and dissipates one milliwatt, followed by a second 1-second charging interval, followed by powering the oscillator of the microradio, again for 1 millisecond, whereby the hysteretic switch operation of the microradio permits relatively slow parasitic charging followed by a burst of energy either to permit the microradio to listen to command signals or to fire off the oscillator of the microradio;
[0050] FIG. 7 is a schematic diagram of the hysteretic switch used in the microradio of FIGS. 1 and 2 , illustrating the firing of the switch based on the gate voltage to one field effect transistor, coupled with a second field effect transistor holding on the switch until the voltage across the charging capacitor drops below a predetermined level;
[0051] FIG. 8 is a diagrammatic illustration of a dual frequency operation of the microradio in which energy is parasitically coupled to the microradio at one frequency, whereas the microradio transmits at another frequency, both utilizing the same antenna;
[0052] FIG. 9 is a block diagram of a multi-frequency charging system for the microradios of FIGS. 1 and 2 , illustrating different antenna paths tuned to different frequencies utilizing different diode detectors, the outputs of which are summed and rectified to provide improved parasitic charging of the final capacitor of the rectifier in the microradio;
[0053] FIG. 10 is a schematic diagram of a voltage multiplier usable as the rectifier in the microradios of FIGS. 1 and 2 , illustrating voltage multiplier stages, each having its own capacitor, coupled to a final storage capacitor for the rectifier in which the voltage multiplier rectifier may be either coupled, to the environment through a naturally radiative structure or to an antenna;
[0054] FIG. 11A is a block diagram of a Colpitts oscillator used in the BFSK modulation of a microradio, showing the switching between the outputs of two Colpitts oscillators under the control of a microcontroller for modulation purposes;
[0055] FIG. 11B is a block diagram of a BPSK modulator, including microprocessor for controlling the outputs to an antenna;
[0056] FIG. 12 is a diagrammatic representation of an invisible or nearly invisible microradio using molecular components for use in attaching to or coating the antenna used;
[0057] FIG. 13 is a diagrammatic representation of the invisible or nearly invisible microradio of FIG. 12 showing the use of a conductive adhesive about the module so that it will stick to an antenna surface and provide electrical contact thereto;
[0058] FIG. 14 is a diagrammatic illustration of an electrode and nanowire as well as the size thereof;
[0059] FIG. 15 is a schematic illustration of a multi-wall nanotube oscillation technique;
[0060] FIG. 16 is a schematic illustration of a doubly clamped diamond beam nonomechanical resonator;
[0061] FIG. 17 is a schematic illustration of a three-terminal nanotube rectifier;
[0062] FIG. 18 is a schematic illustration of a single-electron transmitter constructed from gold electrodes and C60 nanoparticles;
[0063] FIG. 19 is a schematic illustration of an energy storage capacitor consisting of two gold plates and a barium titanate dielectric layer;
[0064] FIG. 20 is a diagrammatic illustration of the layout of a nanoscale microradio;
[0065] FIG. 21 is a perspective three-dimensional layout of a composite microradio in accordance with the subject invention;
[0066] FIG. 22 is a diagrammatic illustration of the generation of a paint or other coating containing microradios, including the provision of microradios in a carrier that is dispersed either by aerosol or paint sprayer onto a surface;
[0067] FIG. 23 is a diagrammatic illustration of the deployment of an aerosol over an area such as a wheat field or other crop for detecting crop health;
[0068] FIG. 24 is a diagrammatic illustration of the deployment of microradios over, for instance, an area that may have improvised explosive devices, with the area being overflown by a satellite that receives signals from the microradios from as much as 10,000 kilometers away;
[0069] FIG. 25 is a block diagram of a multi-user detector system capable of being used when ensembles of microradios are deployed, illustrating the use of a parameter estimation unit in front of a signal separation unit;
[0070] FIG. 26 is a diagrammatic illustration of the manufacture of large numbers of microradios, using a wafer sliced into 100 million microradios, with the microradios occupying a square area on the wafer of 20 centimeters to produce 10,000 microradios along an axis;
[0071] FIG. 27 is a diagrammatic illustration of a microradio formed in the manufacturing process of FIG. 26 , in which the microradio is provided with a conductive adhesive coating about the microparasitic radio wafer element;
[0072] FIG. 28 is a block diagram of a nano-electromechanical resonator coupled to a four-diode rectifier for the filtering of input signals to the rectifier of a microradio;
[0073] FIG. 29 is a diagrammatic illustration of an aerosol can into which paint or other coating containing microradios has been loaded, indicating that with the use of a gas propellant and a high vapor pressure binder, conductively coated microradios can be dispersed as an aerosol from the can;
[0074] FIG. 30 is a diagrammatic illustration of the authentication and tracking of a biohazard container within a further container, with unauthorized entry of the biohazard container being detected through the escape of microradios in an aerosol housed about the vial in the container, assuming that the vial in the container has been violated, thus indicating the violation of either the carton or the vial through the escape of microradios, which are detected at some distance from the container,
[0075] FIG. 31 is a diagrammatic illustration of the ability to access different classes or subclasses of the ensemble of microradios in which two different classes or subclasses can be accessed through an access code generator coupled to a transmitter that transmits the access codes to selected classes or subclasses of microradios;
[0076] FIG. 32 is a diagrammatic illustration of the authentication and coding of a container with a paint or other coating containing microradios on the lid of the container, with the escape of the contents of the container also being determined due to the violation of the container;
[0077] FIG. 33 is a diagrammatic illustration of a pet tracking embodiment in which microradios are embedded in or attached to an animal to provide a tag so that the animal can be traced;
[0078] FIG. 34 is a diagrammatic illustration of the authentication and tracking of an object such as a watch, in which a paint or other coating containing microradios is applied to the watch during manufacture, with the radios being polled and the serial numbers thereof read out by a receiver and stored so as to be able to track and authenticate an object;
[0079] FIG. 35 is a diagrammatic illustration of the utilization of microradios on a vehicle or container in which the microradios are tracked as the vehicle approaches a checkpoint through the utilization of transceiver antennas embedded on the road approaching the polling point;
[0080] FIG. 36 is a diagrammatic illustration of the sensing of fluid flow through the utilization of non-conductive conduits or pipes and the embedding of microradios in the fluid;
[0081] FIG. 37 is a diagrammatic illustration of the tagging of cancerous proteins with a molecule having associated with it a microradio, such that microradios containing molecules are injected into the body of a patient, followed by parasitic powering of the microradios from outside the human body; and,
[0082] FIG. 38 is a diagrammatic illustration of the powering activation and current discharge of the microradio of FIG. 37 from a controller such that the current discharge diminishes or destroys the protein and thus the cancer-causing agent in the patient of FIG. 37 .
DETAILED DESCRIPTION
[0083] Referring now to FIG. 1 and prior to discussing applications of microradios, in its simplest configuration the radio is parasitically coupled to the environment through a connection to a metal or dielectric structure that functions as a naturally radiating structure, here illustrated at 10 . The microradio has an input 12 coupled to structure 10 , at which point a rectifier 14 rectifies RF energy or optical energy to be able to power a radio through a hysteretic switch 16 coupled between the rectifier and an oscillator 18 . As will be described, oscillator 18 will transmit an information-bearing waveform. A variety of analog and digital modulations may be employed, including frequency modulation (FM), amplitude modulation (AM), binary phase shift key (BPSK) and binary frequency shift key (BFSK), among other possibilities.
[0084] It is the purpose of hysteretic switch 16 to toggle the power from rectifier 14 to oscillator 18 . In one embodiment, the output of oscillator 18 is an encoded signal available at output 40 coupled back to structure 10 at point 42 .
[0085] In operation, an RF or optical signal impinges on structure 10 and is rectified by rectifier 14 to charge its final capacitor. The capacitor is contained in the rectifier, or between the rectifier and the hysteretic switch. Once the incoming power is rectified and switch 16 has fired, power is applied to oscillator 18 , for instance over line 26 . Thus, by projecting RF or optical energy onto structure 10 , oscillator 18 is powered and produces the required signal.
[0086] However, the amount of power that can be extracted from the environment using a structure 10 is usually not sufficient to power oscillator 18 for an indeterminate length of time. Moreover, the diodes in rectifier 14 have thresholds that must be overcome in order for the rectifier to work.
[0087] More particularly, when powering a microradio parasitically, one of the first and foremost considerations is the rectifier that takes the RF or optical energy at the microradio and converts it into DC power. One of the challenges for rectifiers is that their diodes have a minimum onset or threshold voltage. As a result one is limited in the forward link in charging the capacitors of the microradio if the detected energy is insufficient to overcome the diode threshold. For instance, it is much harder to charge a microradio than to listen to it or hear it. In other words, practical charging ranges for the radio capacitor are typically much less than typical detection ranges for radio oscillator transmissions. Were the two ranges comparable, it would be found that passive radio tagging range equations would be similar to a radar range equation in the sense that the power returned is proportional to the power transmitted times the power reflected, resulting in a 1/r 4 dependence in which power received back at the transmitter is proportional to power transmitted divided by range to the fourth power. However, due to capacitor charging being less efficient, it is found that power received in the capacitor is proportional to power transmitted divided by range squared, given that once the rectifier receives sufficient power to enable forward diode conduction and capacitor charging, the subsequent oscillator burst is well within detection range. One therefore has to obtain some minimum voltage across the input to the rectifier. Presently rectifiers require on the order of 100 millivolts at the antenna input, but in the subject invention there are two approaches to overcoming charging range limitations associated with the 100-millivolt threshold.
[0088] The first approach is to couple the microradio to a naturally radiating structure such as a metal object, or a dielectric material having some conductivity. A living organism can provide such dielectric material because of its salt content. Coupling to a radiating structure in this manner increases the effective antenna gain of the microradio, thereby increasing the voltage level at the antenna input.
[0089] If, for instance, one wishes to keep track of metallic objects, one can connect the antenna inputs of the microradios to the metallic skin of an object, which serves as a naturally radiating structure. It has been found experimentally in one case that if one seeks to use a micro-antenna about the size of the microradio one can obtain a −4 dB of gain, even though the microradio is a thousandth of a wavelength. It is known from the G=4 pi A/lambdâ2, that antenna gain is related to antenna area A. Given that the microradio antenna is so small, it is clear that the microradio has coupled into the metallic object in this case. Otherwise, the antenna gain would be about 4 pi(1/1000)̂2 using the above equation with an antenna area equal to (lambda/1000)̂2.
[0090] An additional approach to increasing the detection range of the microradios is accomplished through coherent operation of a large number of microradios n, which results in an amplification of the transmitted signal power by n 2 due to coherent combination of the electromagnetic fields generated by each microradio transmitter. Moreover, the opportunity to increase gain is afforded when one uses microradios on an object such as a metallic shell in such a way that the object to which the microradio functions as an antenna.
[0091] Other examples of naturally radiating structures are various parts of vehicles. For instance, if one wants to track a car one can put a microradio on the feed to the car antenna. However, attempting to place a microradio at the feedpoint of an antenna results in many misadventures and proper placement is a rare occurrence. On the other hand, with large numbers of microradios dispersed on a metallic auto part in a suitable paint or other coating in which microradios are suspended or otherwise emplaced or entrained, if the part can function as an antenna then microradio placement is not critical because some of the microradios will be located at an antenna feedpoint or feedpoints.
[0092] For instance, one can consider something like a car door that makes a slot antenna or perhaps even the bumper of a car that makes a horizontal monopole antenna. Applying a suitable paint or other coating containing microradios to these surfaces naturally results in some microradios being optimally placed.
[0093] As will be appreciated, there are a large number of instances where an indigenous material or object can function as an antenna.
[0094] A second approach to more effectively charging the rectifier is to use pulsed charging waveforms. Due to the exponential forward conduction properties of diodes described elsewhere, increasing the input voltage to the rectifier diodes exponentially increases charge current to the capacitor. Therefore, pulsed operation of the charging transmitter generates more current into the capacitor than does steady state operation for the same average power level.
[0095] An additional approach to increasing the detection range of the microradios is accomplished through coherent operation of a large number of microradios n, which results in an amplification of the transmitted signal power by n 2 due to coherent combination of the electromagnetic fields generated by each microradio transmitter. Moreover, the opportunity to increase gain is afforded when one uses microradios on an object such as a metallic shell in such a way that the object to which the microradio functions as an antenna.
Naturally Radiative Structures
[0096] As illustrated in FIG. 1 , the power for the microradio is derived from a structure 10 that in one embodiment is a naturally radiating structure. Here it can be seen that the output 40 of oscillator 18 is coupled directly to this structure as illustrated at 42 .
[0097] Note, the substrate over which the microradios are dispersed, if it can function as an antenna, results in much improved parasitic coupling. The disadvantage is that one has to study the geometry of the object one is tagging in order to know where the opportune tagging spot is. Thus, placing a microradio on an object to obtain suitable gain is not always an easy matter. However, by mass-producing thousands of the particle-size microradios, when sprayed on an object one has an ensemble of returns from all the different microradios, some of which will be at naturally occurring feedpoints, thus to create enough energy to power the microradios.
[0098] Naturally occurring radiative structures can include metal structures with slits or slots in them, or metal structures that have an appropriate antenna length. Moreover, a naturally radiative structure can include animal tissue, which because of its salt content provides sufficient conductivity.
[0099] Thus, when a specialized antenna is not provided for each microradio, as one part of the subject invention one utilizes natural radiative structures.
[0100] Specialized Antennas
[0101] On the other hand and as illustrated in FIG. 2 , output 40 can be connected to an antenna 50 at antenna feedpoint 52 . The use of an antenna improves charging and transmission characteristics of the microradio of FIG. 1 due to the gain of the antenna.
[0102] One approach to overcoming diode thresholds is to provide the microradio with this specialized antenna. Rather than attempting to locate a microradio precisely at the feedpoint of an antenna or depending on random distribution, one can power the microradios utilizing the parasitic paradigm by providing a small standalone antenna coupled to the microradio. When one cannot ensure that the structure on which the microradios are adhered will function appropriately as an antenna, one can provide each microradio with its own antenna.
[0103] It is within the scope of the subject invention to utilize any of a number of small dipole antennas that would be invisible or unobtrusive.
[0104] The antennas serve two purposes. First, the antenna receives ambient RF energy or laser radiation in order to charge the capacitor on the microradio. Second, the antenna radiates an electromagnetic signal when the microradio responds with a burst of transmitted information.
[0105] In one embodiment it has been found that it is possible to be able to efficiently couple energy into the microradios utilizing a dipole antenna constructed from filamentary wires. One can also make the small standalone antenna using microcoils. One can typically achieve effective gain numbers in the range of −40 or −30 dBi looking at these antennas as free-space antennas. Loading the antennas with high-dielectric or high permeability materials will improve antenna gain beyond these values.
[0106] Moreover, a magnetic dipole antenna can be formed in which the loop has a number of microturns. In one embodiment this can be a microcoil staircase with 10 to 20 turns on it. It is noted that the higher the magnetic permeability value μ of the material inside the coil, the higher the gain.
[0107] As will be discussed, the antennas themselves can be fractions of a wavelength such that their size matches the 10-micron size of the smallest of the microradios. It has thus been found that such antennas can be dipoles, coiled antennas, monopoles or other small antennas. In many cases using high permeability materials such as ferromagnetic materials or high dielectric materials such as barium titanate can improve the microantenna efficiency.
[0108] More particularly, as illustrated in FIG. 3 it is possible to provide a microradio 43 , 10 microns-10 millimeters, with a dipole antenna having a tadpole-like design with a 5-millimeter wire 45 extending in one direction and optionally with another 5-millimeter wire 47 extending in a different direction. It is noted that the overall length of these antennas is less than 10 millimeters and one could question their gain or efficiency at the frequencies involved.
[0109] However, it has been found that the dipole wires need not be elongated as dictated by the operating frequency or even stretched out, but can be made to conform to a compact shape such that one could maintain the relatively small size of the microradio and antenna combination.
[0110] The manufacture of such antennas along with the microradios in a highly dense, repeatable semiconductor process will be described hereinafter. However, if the microradios are manufactured with their own dedicated dipole antennas, then the gain of the system can be maximized.
[0111] Referring to FIG. 4 , rather than utilizing the dipoles of FIG. 3 , a microcoil can be used as an antenna in which a coil 49 may be provided with a high-μ material 51 inserted for the purpose of causing the microcoil to resonate at a desirable frequency without having to have an increased diameter. The result is that a microcoil antenna may be provided with a 0 to 3 dBi gain at f=2 GHz. It is noted that the higher the μ of the inserted material, the higher the efficiency of the antenna.
[0112] Referring to FIG. 5 , one can provide a microcoil antenna in a staircase version as illustrated at 53 , with 10 to 20 turns configured as illustrated.
[0113] The staircase is fabricated by successively depositing conducting and insulating layers using a semiconductor fabrication process. For example, the insulating layer can be a standard silicon oxide layer while the conducting layer can be any deposited metallic material.
[0114] The purpose of the staircase antenna is to provide a coil antenna geometry that is compatible with microelectronic fabrication techniques, resulting in an efficient miniature magnetic dipole antenna.
Charging/Transmit Cycle
[0115] Referring back to FIG. 1 , assuming that there is enough power to overcome the thresholds of the diodes in rectifier 14 , in one embodiment there is a charging/transmit cycle protocol that involves the rectifier being charged for, for instance, one to two seconds, whereupon the rectifier is coupled to oscillator 18 to power the oscillator to provide, for instance, a millisecond burst. Thus it is possible with such a regime to utilize relatively inefficient microradios and to be able to provide enough energy to power the oscillator and attendant circuitry for a burst of information.
[0116] If the oscillator is to cyclically broadcast its information, then it simply does so when powered. If, however, in a charge, listen, charge, transmit cycle the microradio must wait for receipt of an activating or control signal. Then when the charging threshold is met, the microradio's receiver is briefly turned on. If there is an activation signal received during this listening period, the capacitor is recharged over a long cycle followed by activation of the oscillator to produce a microburst. Note that external activation can occur by irradiating the microradio with a laser pulse, or by an RF control signal.
[0117] Regardless of the external activation of the oscillator, it is the purpose of the hysteretic switch 16 to allow the final capacitor within rectifier 14 to charge up for a relatively long period of time before hysteretic switch 16 goes into conduction and passes the power from this capacitor to oscillator 18 . The result is a powering cycle, as illustrated at waveform 24 , that causes the capacitor to charge up to a threshold point 26 , at which the capacitor is rapidly discharged as illustrated at 48 through oscillator 18 .
[0118] The result is that the charging interval, as indicated by arrow 30 , is much longer than the transmit interval illustrated by double-ended arrow 32 .
Timeline
[0119] Central, however, to the ability to provide the microradios with the ability to transmit over significant distances is the powering cycle timeline and the micro-receiver elements shown in FIGS. 6A and 6B .
[0120] Referring now to FIG. 6A , assuming for instance that one has a rectifier 14 , hysteretic switch 16 and an oscillator 18 , this scenario would be useful when one did not wish to have control signals to operate or activate a microradio. However, if one wishes to have a control signal scenario, one needs to have the output of hysteretic switch 16 coupled through a single-pole double-throw switch 42 to, in the first instance, establish a listening time period, which is established by powering receiver 44 . Upon the powering of receiver 44 , the receiver is coupled to antenna 50 by virtue of circulator 52 .
[0121] Upon receipt of command signals, receiver 44 is operably coupled to control 46 to switch 42 to switch power to oscillator 18 so as to activate oscillator 18 to provide a signal back through circulator 52 to antenna 50 . Oscillator 18 may be modulated by a modulator 48 for providing whatever information is required to be transmitted at this point, given the receipt of control signals for the microradio to do so.
[0122] Referring to FIG. 6B , here it can be seen that the timeline includes a charging period 55 , which may be on the order of a second and which allows a final capacitor in rectifier 14 to be charged, for instance, to 1 microjoule. Thereafter, as illustrated at 57 , there is a listening portion of the timeline that may offer a short 1-microsecond to perhaps one millisecond listening time slot. The command receiver consumes approximately one milliwatt of power to power the microradio's receiver for the listening operation. The command period enables reader authentication and timing synchronization with the microradio.
[0123] Thereafter, there is another one-second charging interval, here illustrated at 59 , followed by a short period 61 of approximately one millisecond duration for the oscillator to generate a one-milliwatt burst.
[0124] Thus one embodiment of the subject invention includes developing an optimal charging/transmit cycle timeline in which one charges the final capacitor, for instance, for one second, after which one would listen for command signals during one millisecond, again charging the capacitor for one second and then powering the oscillator for one millisecond.
[0125] By use of this cycling one can charge the capacitor from the parasitic coupling for relatively long periods of time, whereupon the device can listen for instructions from the outside world and emit a short burst, followed by another charging period, and another burst. This charging regime is very effective for parasitically powered microradios and is available for any microradio application.
Hysteretic Switch
[0126] Referring now to FIG. 7 , a hysteretic switch in one embodiment includes two CMOS FET transistors in which a transistor 63 , here labeled N 1 , senses the voltage at capacitor 64 by having its gate coupled to a voltage divider coupled between the capacitor and ground as shown by resistors 65 and 66 . Note that a pull-up resistor 67 is provided. Note that when the gate voltage V g of transistor 63 is greater than V thn then the gate of PFET transistor 68 is such that transistor 68 connects capacitor 64 to a load 69 , which in this case is oscillator 18 of FIGS. 1 , 2 and 3 . An FET transistor 70 keeps transistor 68 in its conducting region to hold it on until capacitor 64 discharges below the useful supply voltage level to the oscillator load 69 .
[0127] In one embodiment it is the goal of the hysteretic switch to switch on when the input voltage is greater than, for instance, 1.5 volts. Note, it is desired that the rectified power provide up to 2 volts across the output capacitor, which in one embodiment is a 2 microfarad capacitor.
[0128] When the storage capacitor is being charged up, the hysteretic switch is open. When the threshold or trip point is exceeded, the hysteretic switch connects the capacitor to the load, in this case the oscillator. The load then draws current from the capacitor and begins to discharge it. In one embodiment, when the capacitor voltage drops below the threshold voltage, the hysteretic switch stays on. When the capacitor voltage drops below 1 volt, the switch disconnects the load from the capacitor, the capacitor starts to charge up, and the cycle repeats.
[0129] Referring now to FIG. 7 , a hysteretic switch in one embodiment includes two CMOS FET transistors in which a transistor 63 , here labeled N 1 , senses the voltage at capacitor 64 by having its gate coupled to a voltage divider coupled between the capacitor and ground as shown by resistors 65 and 66 . Note that a pull-up resistor 67 is provided. An FET transistor 68 connects capacitor 64 to a load 69 , which in this case is oscillator 18 of FIGS. 1 , 2 and 3 . An FET transistor 70 keeps transistor 68 in its conducting region to hold it on after a capacitor voltage threshold is reached. Note that when the gate voltage V g is greater than V thn , then capacitor 64 is dumped to load 69 .
[0130] In one embodiment it is the goal of the hysteretic switch to switch on when the input voltage is greater than, for instance, 1.5 volts. Note, it is desired that the rectified power provide up to 2 volts across the output capacitor, which in one embodiment is a 2 microfarad capacitor.
[0131] When the storage capacitor is being charged up, the hysteretic switch is open. When the threshold or trip point is exceeded, the hysteretic switch connects the capacitor to the load, in this case the oscillator. The load then draws current from the capacitor and begins to discharge it. In one embodiment, when the capacitor voltage drops below 1 volt, the hysteretic switch turns off and the cycle repeats.
[0132] Note in the circuit of FIG. 7 , transistor 68 is a PFET, with pull-up resistor 67 keeping this transistor off while the capacitor charges up. Transistor 63 is an NFET that senses when the capacitor voltage is high enough. Resistors 65 and 66 form a voltage divider that feeds the gate of NFET 63 , which selects the trip point. Note the resistors must be of high resistance so that the capacitor is not drained faster than it is being charged.
[0133] Transistor 70 is also an NFET that holds switch 68 on as capacitor 64 discharges and provides the subject hysteresis. It is noted that transistor 68 will not switch off until the load voltage drops below transistor 70 's threshold voltage, which in one embodiment is approximately 0.5 volts.
[0134] While the circuit of FIG. 7 functions properly, the sub-threshold leakage current in transistor 63 can in some instances keep capacitor 64 from charging up to 1.5 volts. In order to solve this problem one must keep the leakage current well below one micro-amp until the capacitor 64 voltage is above 1.5 volts.
[0135] To minimize the sub-threshold leakage problem, there are several circuit designs, one of which is suggested by E. Vittoz et al. in the following IEEE Journal article: Vittoz, E.; Fellrath, J., “CMOS analog integrated circuits based on weak inversion operations,” Solid - State Circuits, IEEE Journal of, Vol. 12, no. 3 pp. 224-231, June 1977. Additionally, it is possible to utilize bipolar transistors as can be seen in the 1965 IEEE article by Gaertner, W W., entitled “Nanowatt devices,” Proceedings of the IEEE, vol. 53, No. 6, pp. 592-604, June 1965. A further solution is to utilize an auxiliary capacitor isolated from capacitor 64 that is driven by the same source and which powers the hysteretic switch control circuit. Moreover, one can deliberately bias all FETs to operate at nano-amp levels where the functions provided by the circuit can operate with Idd's below 1 micro-amp.
[0136] It is a feature of the subject invention due to the charging regimes discussed above that the storage capacitor, while preferably a supercapacitor, need not be one. The reason in the past for super storage capacitors was to be able to store enough power in a small enough physical capacitor to be able to power the traditional RFID tag-type radios.
[0137] However, with the use of the hysteretic switch it has been found that storage on more conventional capacitors, even though resulting in a crude microradio, nonetheless provides sufficient output.
[0138] Thus a charging regime that uses a hysteretic switch and takes place over multiple seconds or minutes compared to a microburst from an oscillator permits smaller, less dense storage capacitors to be used.
[0139] It is this type of regime that enables relatively crude transceivers to develop enough power to extend range. This is unlike an RFID tag, whose power is derived parasitically but which is used immediately so as to function as a smart reflector.
[0140] In order to achieve the charging/transmit cycle, the hysteretic switch's function is to keep the final capacitor of the rectifier from leaking towards the oscillator such that power is allowed to build up in the final capacitor of the rectifier for later dumping into the oscillator.
[0141] While several types of hysteretic switches are possible, the simplest, of course, is to provide a transistor coupled to the final capacitor and to bias the transistor in such a way, either naturally or with circuit elements, so that it goes into conduction only after a predetermined charge has built up on the final capacitor. Thereafter it remains in conduction until the oscillator has drained a sufficient amount of voltage from the capacitor and the capacitor voltage output drops below the point at which conduction is no longer sustainable.
Dual Frequency Operation
[0142] Referring to FIG. 8 , it is possible to charge rectifier 14 by irradiating antenna 50 with energy having a frequency f 1 , with the rectifier having a filter 54 at f 1 interposed between feedpoint 52 and the rectifier: In one embodiment, oscillator 18 may be made to oscillate at a different frequency, namely frequency f 2 , as illustrated by filter 56 , such that the oscillator transmits electromagnetic radiation at a different frequency than the energy, is received in order to charge up the final capacitor of rectifier 14 . One reason for doing this is to increase the efficiency or range of the microradio by avoiding leaking the transmitted energy back into rectifier 14 .
[0143] Another reason for providing the two-frequency system is to simplify the design of the microradio detector, or reader. Specifying different frequencies for charging and transmission allows for a less complex microradio reader receiver design. This is because if the charging and transmit signals are on the same frequency, they will interfere. Isolation and co-site interference cancellation would required to separate the strong cochannel charging signal being transmitted by the reader from the much weaker signal returned by the microradio.
[0144] It has been found that if f 1 is offset by between 0.9 f 2 - to 1.1 f 2 , these frequencies are sufficiently different to derive the above benefits.
[0145] Thus, for more efficient capacitor charging, in one embodiment charging current is provided by charging with RF energy at one frequency, whereas the information derived from the radios is derived by listening to an adjacent frequency. In one embodiment, for instance, the charging frequency is approximately from 0.9 to 1.1 of the listening frequency.
Multiple-Frequency Charging
[0146] Referring now to FIG. 9 , it has also been found that the microradio can be more efficiently charged by providing, for instance, an array of antenna outputs 71 , 72 , 73 and 74 outputted to an antenna 80 and each tuned to a different frequency, here shown as f 1 , f 2 , f 3 and f 4 . These can be provided with corresponding delay elements, 75 , 76 , 77 and 78 , the outputs of which are summed at 79 .
[0147] The result at rectifier 14 in terms of the charging of the final capacitor thereof is that a tag reader that is limited in peak transmit power can sequence between a multiplicity of transmitted charging frequencies. The frequency sequence and the delays are arranged so that the power transmitted at each frequency arrives simultaneously at the summer input. This technique takes a continuous wave charging signal and groups it into a set of pulsed inputs to the rectifier. The reason for doing so is that diodes are exponentially inefficient devices. That is, the conduction current through the rectifier diodes drops exponentially with respect to input voltage. By pulsing the charging inputs, the diodes operate in a more efficient conduction regime. Even though the net duty cycle is less than for a continuous charging input, the smaller total charging time is more than compensated by more efficient diode conduction during the higher energy pulsed inputs. The resultant output of oscillator 18 is applied to a transmit antenna 83 in the manner previously described.
[0148] Thus in one embodiment, it is possible to rectify different frequencies of RF radiation through different antenna outputs. This means that with multiple frequencies irradiating the ensemble of microradios, the amount of power to the diodes in the rectifier is increased, thus to exceed diode thresholds and to improve diode conduction efficiency.
Voltage Multiplier
[0149] Referring now to FIG. 10 , in one embodiment rectifier 14 is a voltage multiplier incorporating diodes 81 , 82 , 84 , 86 , 88 and 90 coupled in series to antenna 92 , feedpoint 94 .
[0150] Each stage of the voltage multiplication includes a capacitor 96 to ground between the output of a previous diode and the next diode such as indicated at points 98 . The output of diode 90 is directly coupled to final storage capacitor 100 , where capacitors 102 and 104 accumulate respectively the outputs of diodes 82 and 86 such that the charges on capacitors 102 and 104 are applied across storage capacitor 100 and ground. The operation of voltage multipliers is well known, and all result in a charge on a final storage capacitor.
Modulation for the Microradio
[0151] Referring now to FIG. 11A , one of the most easily implemented modulation schemes takes oscillator 18 and divides it up into two Colpitts oscillators, namely oscillators 130 and 132 , each operating at a different frequency. With such a scheme one can control the outputs of oscillators 130 and 132 via a switch 134 under the control of a microcontroller 136 to provide a BFSK modulation scheme in which the output of switch 134 is coupled to an antenna 138 or coupled to the environment through a naturally radiating structure.
[0152] Alternatively, as illustrated in FIG. 11B , one can have a BPSK modulator in accordance with the Taub and Schilling design shown there.
[0153] In this embodiment, an oscillator 140 opened up by a hysteretic switch 142 generates a sinusoidal output. One pathway for the output goes straight to a switch 144 . The other goes through a 180-degree phase shifter 146 . A microcontroller 148 controls the switch to select which output couples to an antenna 150 or a naturally radiating structure. What will be appreciated is that whatever modulation scheme is used for the microradio, information can be transmitted from one or more of the microradios in accordance with sensed data or simply in accordance with a registration code so that one could identify the individual microradio providing the transmission. This is quite similar to RFID tag-type of registrations that, as will be seen, can be manufactured directly into the microradio at the time of manufacture.
[0154] Moreover, modulation of the radio may be accomplished by using two Colpitts oscillators, one resonating at one frequency and another at a different frequency, thus to provide the mark and spaces to be transmitted by the microradio. For this purpose one could also use a Taub and Schilling BPSK modulator.
[0155] For the purpose of this invention, a “Colpitts oscillator” will be considered to be a radio frequency (RF) oscillator that uses a single, untapped inductor with a combination of two fixed capacitors in series connected in parallel with the inductor. A “Binary Frequency Shift Keyed (BFSK) modulator” is a modulator comprised of two distinct oscillators and a switch selecting between the oscillators depending upon whether the data bit is a mark or a space. A “Taub and Schilling Binary Phase Shift Keyed (BPSK) modulator” is a modulator which has an oscillator, a direct path to a switch, and a 180° phase shift path to a switch, wherein the switch selects between the two paths depending upon whether the data bit is a mark or a space.
[0156] As will be seen, the ability to provide a modulated signal from such a microradio permits a wide variety of applications described above.
Nanoradio Implementation
[0157] More particularly and referring now to FIG. 12 , a microradio is shown utilizing nano-electronic components. Here microradio 210 is comprised of electrodes 222 which connect the circuits within a module to a conductive adhesive coating 224 which when deployed to an antenna connects the internal circuits of the module to the antenna.
[0158] In cases where a protective coating prevents direct conductive coupling with the target antenna, electrical coupling is possible using capacitive, inductive or radiative techniques, usually at the cost of greater insertion loss and consequent higher stored energy requirements.
[0159] For this purpose an antenna coupling 226 is utilized to couple the radiated energy from the antenna to a rectifying circuit 228 which may be a nanotube rectifier incorporating a single electron transistor. The output of the rectifying circuit is coupled to a capacitor 230 which is constructed from thin plates as are used to fabricate nano-electrodes, with the capacitor in turn coupled to an oscillator/amplifier 232 . The capacitor includes a switch that closes upon receipt of a command signal in order to activate the oscillator. Oscillator/amplifier 232 may include a nanowire resonant tunnel diode or a transistor for RF purposes, or a high efficiency quantum dot LED or a small laser, for example, a quantum cascade laser for infrared purposes. In the illustrated embodiment, the output of the oscillator/amplifier is delivered to an antenna coupler 234 that is connected to electrode 222 to couple out the signal available at the output to the conductive adhesive coating 224 .
[0160] The device thus formed is a parasitic device that derives its power from rectifying the RF energy at the surface of an antenna. In the IR case, the rectifying circuit may also be utilized to rectify optical energy to charge capacitor 230 , or it may rectify radio frequency energy from a nearby radio transmitter used for communications or radar.
[0161] The second part of the microradio includes a command channel which is to receive signals to activate the radio and for this purpose an antenna coupler 240 , which may include nano-electrodes or nanowires, and couples signals from a conductive adhesive 224 to a command channel frequency detector 242 which is in turn coupled to controller 218 . Controller 218 , upon receipt of an authorizing signal, activates a switch signal 228 to discharge the capacitor 230 to power oscillator 232 , thereby to generate the signal. This signal is applied through antenna coupling 234 to electrode 222 and thus to conductive adhesive layer 224 , which in turn directly couples the output of the oscillator/amplifier to the antenna to which it is connected.
[0162] It will be noted that command channel detector 242 may be implemented as a frequency detector. This implementation is especially compatible with designs intended to minimize parts by using common apertures for command reception and for monitoring other transmitters.
[0163] Referring to FIG. 13 , each of the microradios 210 is illustrated having the conductive adhesive 224 coupled to an electrode 222 that exists at the base of the module. Thus, the encapsulation of the modules in a conductive material such as a conductive grease renders the module attachable to any surface it contacts and more importantly a surface of an antenna.
[0164] If on the other hand an optical system is used, then an optical coupler layer surrounds microradio 210 , with the optical coupler layer both parasitically receiving light energy from a target light source and at the same time injecting light energy elsewhere.
[0165] As mentioned above, in one embodiment the command receiver consists of an antenna coupling that couples radiation incident on the antenna to frequency detector 242 tuned to the command link frequency, as shown in FIG. 12 . The frequency detector is kept to a simple pulse detector in order to facilitate implementation at the nanometer scale. Pulses detected by the frequency detector 242 are output to controller 218 , with a simple pulse pattern being provided as a rudimentary command set. As will be appreciated, frequency detectors can conserve command link power if they support spread spectrum modulation.
[0166] In operation, switch 228 discharges capacitor 230 driving oscillator/amplifier 232 . The generated power is delivered directly into the antenna through coupling 234 .
[0167] What is now discussed is how nanotechnology can reduce the size of the components in the module shown in FIG. 12 so that the module is invisible to the unaided eye.
Antenna Coupling
[0168] Assuming that the microradio shown in FIG. 12 is placed directly on an antenna, a conductor must extend from the device to the radiating surface. Much recent work has been done on developing electrodes with nanowires for electrical conduction. See, for example, Khondaker and Yao. In this reference and as shown in FIG. 14 , a pair of 500 nm electrodes fabricated with standard optical lithography are connected to gold nanowires with diameters ranging between 5 nm and 50 nm. These nanowires can be connected to nanoscale devices, providing an interface coupling the microradio to the antenna through the small electrodes and conductive adhesive 224 . A chemical agent such as conductive adhesive 224 bonds the electrode to an antenna. In a separate reference, Thong et al. fabricated tungsten nanowires with diameters less than 4 nm. Such an electrode and wire is shown in FIG. 14 by a 500 nm electrode 270 coupled to a 50-nm nanowire 272 .
Frequency Detector
[0169] Nanomechanical resonators are actively developed by many groups including NASA and the Caltech Jet Propulsion Laboratory. As can be seen in FIG. 15 , nanotubes 276 formed in multiple concentric tubes 278 tend to oscillate at near-gigahertz frequencies. These multi-walled nanotubes are just nanometers in diameter. In 2000, John Cumings and Alex Zettl of the University of California at Berkeley showed that after peeling open one end of a multiwalled tube, the inner tubes 276 could slide in and out with very low friction. The calculations also demonstrated that the van der Waals force, which attracts all neutral atoms to one another through electrostatic attraction due to molecular polarization, caused the inner nanotubes 276 to be pulled back inside the sheath of outer tubes 278 . These tubes can be used as receivers sensitive to high frequency electromagnetic signals, resonating in time to the incoming electromagnetic wave.
[0170] As shown in FIG. 16 , while oscillating multi-walled nanotubes remain theoretically attractive, Sekaric et al. at Cornell and NRI, recently built and operated a nanomechanical resonant structure in nanocrystalline diamond with a resonant frequency of 640. MHz. The device Q factors were about Q=f/Δf=2400-3500. The device size includes a diamond beam 280 supported between two clamps 282 spaced apart by 2 μm.
Charge Switch/Rectifier
[0171] One attractive aspect of a microradio is that it can draw power parasitically from a host antenna. No internal power source is required. Power is drawn from the host antenna whenever it transmits by using an antenna coupling feeding into a rectifier that charges a capacitor. As shown in FIG. 17 , nanotube rectifiers have been demonstrated experimentally by Papadopoulos et al. Here it can be seen that multiwalled nanotubes 284 are joined together at one end 286 , with their other ends 288 coupled to metallic leads 290 . Current flow is indicated by arrow 292 . Recent calculations by Meunier et al. showed that the one-way current flow observed experimentally is due to the critical role played by the metallic contacts in the rectification process. These authors state that rectification is possible with a suitably constructed two-terminal device.
Switch
[0172] Referring to FIG. 18 , a transistor switch is provided through a single-electron transistor. Wu et al. have recently fabricated a single-electron transistor that is about 400 nm on a side. Here the transistor is composed of drain 294 , source 296 and gate 298 , with the biasing as shown. Note that C60 describes a ball-shaped carbon molecular structure known as a fullerene. The single-electron transistor has a great advantage in low power consumption and high packing density. By combining advanced electron-beam lithography and nanophased-material synthesis techniques, Wu et al. built and tested a single-electron device with an gold-colloidal/fullerene island. The gate electrode tunes the potential of the electrode islands.
Capacitor
[0173] A capacitor is needed to store energy for the microradio. As illustrated in FIG. 19 , using thin film and nanofabrication technology, it is possible to make a very small parallel plate capacitor. Here one has a BaTiO 3 layer 300 sandwiched between Au conducting layers 302 . Nanowires 304 are connected to layers 302 . In one embodiment, the energy requirement is dominated by the need, for instance, to transmit ten microwatts for one millisecond from the microradio tag. As a result, the capacitor must store only 10 nJ of energy. The energy stored in the capacitor is given by 1/2CV 2 . Assuming that the capacitor can be charged to a few volts, the capacitance of the nanocapacitor must be about 10 nF. The formula for the capacitance of a parallel plate capacitor is
[0000] C= 0.0885ε r A/t
[0000] (van Valkenberg, p 6-14), where C is the capacitance in pF, ε r is the dielectric constant relative to air, A is the parallel plate area in cm and t is the plate spacing in cm. Using a ferroelectric material like barium titanate (BaTO 3 ), dielectric constants as high as 11,000 is possible. Within a 10 nm BaTO 3 layer deposited between two conducting electrode plates, the required area is found from
[0000] 10×10 3 =10 3 A/ 10 −6 .
Solving for A:
[0174] A= 10 −5 cm 2 .
[0175] The length of a plate side is therefore 3×10 cm or 30 μm. This dimension could be reduced to 3 μm by stacking one hundred plates or distributing one hundred capacitors over the energy storage component. Note that the capacitor is the largest of the components for the module. Care must be taken to ensure that the BaTiO3 or other material is deposited uniformly so that holes do not develop that will short out the capacitor.
Controller
[0176] A device containing logic and memory is necessary to control the various components in the microradio. It could consist of a few logic and memory elements or could be as sophisticated as a microcontroller. Work in this domain is exemplified by the work of Wu et al. One example of a microcontroller may be implemented with single electron transistors and memory cells. Another is nanometer-scale microprocessor development work at Intel (Bohr) and elsewhere (Wong et al.).
[0177] The applications targeted by molecular electronics, Moletronics, programs fall into two principal areas, both of which emphasize circuit architecture:
[0178] As to logic devices, the design, synthesis, and testing of two interconnected molecular logic gates connected to the outside world produce a correct truth table. The devices operate at room temperature, and the demonstrated configuration is scaleable to densities of greater than 10 12 gates per square centimeter.
[0179] As to memory devices, the design, synthesis, and testing of low-power, high-speed circuit architectures for high-density, terabit-level memories is based on molecular electronic devices. The devices have a functional 16-bit molecular memory connected to the outside world at a density of 10 15 bits per cubic centimeter. The molecular memory is capable of performing a storage function at room temperature that is bistable and reversibly driven from one state to the other by an outside signal.
[0180] While these microprocessors are difficult to produce, an interim solution uses nanoscale CMOS with devices in the 10-100 nm size regime as described by Wong et al.
[0181] Bohr discusses other approaches to logic elements, including carbon nanotube FETs described by Bachtold et al. Bachtold et al. have constructed and demonstrated functioning logic elements including an SRAM memory cell using nanotubes.
[0182] Huang et al. built and demonstrated functioning FETs and logic elements using combinations of Si and GaN nanowires. Dimensions are on the order of molecular sizes, with on-off current ratios around 10 5 .
[0183] Single-electron transistors have been briefly discussed. Their dimensions are around one nanometer, using quantum dots. Chen et al. numerically simulated a functionally complete set of complementary logic circuits based on capacitively coupled single-electron transistors (CSETs). The family included an inverter/buffer stage, as well as two-input NOR, NAND, and XOR gates, all using similar tunnel junctions, and the same dc bias voltage and logic levels. Maximum operation temperature, switching speed, power consumption, noise tolerances, error rate, and critical parameter margins of the basic gates have been estimated. When combined with the data from a preliminary geometrical analysis, the results indicate that implementation of the CSET logic family for operation at T˜20 K will require fabrication of structures with ˜2-nm-wide islands separated by ˜1-nm-wide tunnel gaps. Getting the device to operate at room temperature requires smaller islands.
[0184] It is also possible to build still smaller transistors using quantum-dot cellular automata. Orlov et al. built a micron-scale device that is theoretically predicted to work at room temperature if scaled down to a nanometer.
[0185] Finally, others are exploring single-molecule transistors. See, for example, Reed. In addition to the extreme degree of miniaturization, a benefit to molecular-scale electronics is the capability for self-assembly through chemical synthesis.
Trigger
[0186] The trigger contains elements that have already been discussed. Some logic, memory and switching are needed to arm the trigger, monitor receiver output lines, possibly operate a timer and to switch on the microradio.
Oscillator and Amplifier
[0187] An oscillator and transmitter are needed to drive electrical current from the microradio into its antenna. One approach is to use a nanomechanical resonator in a resonant tank circuit. The electrical output is amplified through a carbon nanotube FET, nanowire FET or some other small structure capable of coupling to the oscillator. This device is in turn amplified by a small CMOS FET or other device capable of delivering about 1 μW output power to the coupled antenna. This 1 μW output power is found by calculating the minimum power needed to receive microradio transmissions at distances comparable to feasible tag charging distances.
[0188] Another approach is to use a nanowire resonant tunnel diodes. Björk et al. fabricated a nanowire resonant tunneling diode from semiconductor nanowhiskers. Device size is about 40-50 nm diameter whiskers on a SiO 2 -capped silicon wafer.
[0189] Based on these component estimates, it is possible to lay out a footprint estimate for the nanoscale microradio. FIG. 20 shows a 2000×2500 nm device 400 containing a complete microradio, including command receiver, rectifier and transmitter. The size is predominated by the energy storage capacitor 402 , the controller 404 and the three coupling electrodes 406 . Power dissipation and consumption are not issues as energy is drawn parasitically from the antenna, even between oscillator bursts. Weight is estimated at a few picograms (10 −12 grams) and the size is 2500 nm×2500 nm, clearly invisible to the unaided eye. Note that when embodied in nanoscale components, rectifier 408 , frequency detectors 410 , oscillator/amplifier 412 and trigger 414 do not contribute significantly to overall size. The two elements primarily determining device size are the energy storage capacitor and the antenna coupling electrodes.
[0190] A three-dimensional view is shown in FIG. 21 . The design has two layers 420 and 422 . The primary layer 420 holds most of the electronics. The second layer 422 is allocated for two functions. First, some sort of bonding agent is needed above the electrodes to ensure good contact with the target antenna. This contact can be mechanical, chemical, electrochemical, or some combination. The rest of the second layer provides additional room for a bank of energy storage capacitors.
[0191] What is provided by the subject invention is a crude, inexpensive, unobtrusive microradio whose non-optimal response can be compensated for both by the numbers of microradios and by having an exceptionally large aperture, high-power amplifier on the microradio reader so that large amounts of power can be projected towards the microradio ensemble to charge the inefficient small radios.
Massive Deployment Applications
Paint and Aerosol Dispersion
[0192] Referring now to FIG. 22 , because of the possibility of making massive numbers of microradios, programming them and distributing them, it is possible to enable a large number of applications that could not be serviced utilizing single microradios.
[0193] In one embodiment one carries a slurry of microradios in a carrier as shown at 500 and supplies them in one embodiment to a paint sprayer 502 , which forms a cloud of paint droplets 504 containing microradios that impinge upon a surface 506 . This technique, may be used to coat many types of surfaces, including individual parts, vehicles, or other articles that require some kind of microradio assist, either in tracking, authentication, identification, sensing or the like.
[0194] As shown in FIG. 23 , an aircraft 508 such as a crop duster may deploy a fog 510 of microradios entrained in an aerosol over the ground 512 , with the microradios in one embodiment providing sensors with crop health information transmitted to a receiving antenna. Here the crop duster may be provided with a radio antenna, such as microwave horn 514 , which can transmit powering signals to the ground as illustrated at 516 , whereupon return signals with information on them are transmitted towards aircraft 508 as illustrated at 518 .
[0195] Assuming that the microradios have suitable sensors, the same aerosol massive deployment of microradios can be used, for instance, in detection of improvised explosive devices, with the aircraft being able to power the microradios on the ground from, for instance, a distance of 100 feet, and receive the return signals.
[0196] Additionally and as will be discussed, as shown in FIG. 24 , a satellite 520 may be used to overfly an area on the ground 522 and assuming that a paint or other coating containing microradios or aerosol-dispersed ensemble of microradios is available, with coherent processes that will be described, microradios if powered either by the ambient or some other parasitic means can be detected by the satellite at a distance of, for instance, 10,000 kilometers. Here the ensemble of microradios is shown by dots 523 .
Coherent Operation and Multi-User Detection
[0197] Referring now to FIG. 25 , when an ensemble of microradios is deployed either in a paint or other coating containing microradios or by aerosol projection, assuming that the radios are all operating on the same frequency due to the fact of their manufacture and due to the inability to easily program each of the microradios with a different operating frequency, multi-user detection techniques are employed. Multi-user detection techniques in general permit the demodulation of signals that are transmitted on the same frequency and using the same modulation type. It has been found that multi-user detection techniques such a described in U.S. Pat. No. 6,947,505 to Rachel E. Learned entitled “System For Parameter Estimation and Tracking of Interfering Digitally Modulated Signals,” assigned to the assignee hereof, and U.S. patent application Ser. No. 09/923,709 filed Aug. 7, 2001 to Rachel Learned entitled “Method For Overusing Frequencies to Permit Simultaneous Transmission of Signals From Two or More Users on the Same Frequency and Time Slot,” as well as U.S. Pat. No. 6,839,390 to Diane Mills entitled “Voting System For Improving the Performance Of Single-User Decoders Within an Iterative Multi-User Detection System.” Other multi-user techniques are described by Robert MacLeod in U.S. patent application Ser. No. 10/105,918 filed Mar. 25, 2002 entitled “System For Decreasing Processing Time In an Iterative Multi-User Detector System,” as well as U.S. patent application Ser. No. 10/134,330 filed Apr. 29, 2002 by Diane Mills entitled “Method and Apparatus For Random Shuffled Turbo Multiuser Detector.”
[0198] What will be seen from this suite of multi-user detector cases is that, in a multi-user detection system in which interfering signals are purposely allowed to exist, a parameter estimation unit can be provided that utilizes signal processing for determining the channel transfer function for each received signal, including the received power, phase of the oscillator, timing offset relative to the base station clock carrier frequency, carrier frequency offset and a number of multi-path replicas and delays for each replica, with the system providing real-time uninterrupted estimates of these parameters required by the signal separation unit.
[0199] Note that multi-user detection is described by S. Verdu in a book published by the Cambridge University Press in 1998.
[0200] Note that it is the purpose of the multi-user detection system utilizing a parameter estimation unit to be able to derive channel parameters that uniquely distinguish the characteristics of each individual signal regardless of the fact that the signals exist in the same communications bandwidth and at the same instant in time. These parameters are required by any signal separation system for highly loaded or overloaded systems of users and in general include, for each signal, the channel transfer function comprised of the received power, the phase of the oscillator that generated each received signal, the timing offset relative to base station clock, any frequency offset of the carrier, and the structure of the multi-path replicas.
[0201] As described in this patent, the received power of the signals varies substantially from burst to burst, which means that the parameter estimation becomes somewhat difficult. Likewise the phase of the oscillator can also vary from burst to burst, as can the timing offset, which is the variance of when the signals are to be received in a particular timing slot of the communications system. Conversely, the burst length is usually known to within a fraction of a symbol period. Not only can all of these parameters change on a burst-by-burst basis, the frequency of the carrier can also change, most notably due to Doppler shifts and thermal drift.
[0202] The result is that signal separation become increasingly difficult in the changing environment where a number of the microradios are trying to communicate with the base station on the same channel.
[0203] Note, for multi-user detection systems there is a need to be able to dynamically adapt to the changing signals occasioned by the fact that one cannot dictate the fixed nature of the transmitters and to the fact that the power adjustment for each of the transmitters in one embodiment is adjusted by the base station, sometimes on a burst-by-burst basis. This case is the same when multi-user detection is applied to microradios.
[0204] Moreover, it is important that a multi-user detection system be able to operate with various coding schemes and various error interfaces.
[0205] In this patent, in order to be able to accommodate multiple interfering signals on the same communication channel in which the signals are purposely allowed to interfere with one another, to be able to make maximum use of a traffic channel, initial estimates are made of various parameters utilizing the interference-free receive signal on an acquisition channel and the usual traffic channel training sequences that are transmitted to identify each mobile user and to set up timing for the burst transmission from the microradio. In the case of microradios, acquisition channels may be defined by individually addressing radios in order to obtain a comparatively uninterfered transmission from the microradio. In this case, many parameters can be estimated and stored for future detections. Such an approach would be of most value for embedded sensor applications and other applications where multiple interrogations of the same radio are most desirable.
[0206] It is a feature of the Learned invention that with the estimate of various parameters, signal separation can in fact take place.
[0207] Not only is the multi-user detection system usable with various coding schemes, it is also usable with the BFSK modulation scheme for the microradios. As can be seen in FIG. 25 , each of the microradios, here illustrated at 524 , transmits to a transceiver 525 ; which is utilized not only to parasitically power the microradios but is used to receive the transmission from the microradios.
[0208] Each of the microradios has certain characteristics even though they are transmitting on the same frequency at the same time. These characteristics are coupled to a parameter estimation unit 526 , which through processes described in the Learned patent provide estimates of power of each of the signals, oscillation phase of each signal, timing offset relative to the transceiver clock, carrier frequency offset and multi-path structures. Having these parameters estimated, one can use either conventional multi-user detection techniques in signal separation unit 527 or more sophisticated signal separation techniques described in the aforementioned patents and patent applications.
[0209] It is important to note that if each of the microradios in an ensemble of microradios transmits at a different time, then it is possible to demodulate the information content from an individual microradio. Timing, however, for such a read-out of the microradios is somewhat problematic due to the fact that it may not be easy to control when each of the microradios transmits. Thus time division multiplexing, while possible with a paint or other coating containing microradios or aerosol-dispersed ensembles of microradios, is not as robust as would be liked.
[0210] On the other hand, it is possible through transmissions from transceiver 525 to issue control signals to the microradios to have the microradios transmit coherently, meaning that they are on and off at the same time and transmit on the same frequency. Using this controlling technique, it is even possible to assign time slots to each microradio so that they transmit at separate times. However, multi-user detection techniques may be preferable in cases where it is possible to use such sophisticated digital demodulation techniques to separate interfering signals.
[0211] While it would be thought that it would be impossible to disambiguate the signals or separate them, the aforementioned multi-user detection techniques when applied to BPSK or other modulation schemes utilized by the microradios permits the demodulation of all of the coherently actuated microradios.
[0212] Thus even if the radios are coherently operated, the multi-user detection techniques provide a way to separate out the signals and to provide a readout of the information from each of the microradios.
[0213] Even if the microradios are all transmitting the same information, it is nonetheless important to be able to utilize multi-user detection techniques. It is noted that each of the microradios is provided at the factory with a unique serial number, primarily to permit identification of the signals from each of the individual microradios. This being the case, even though the information from the microradios may be the same, the identity of the microradios is still important.
[0214] Thus coherent operation may be important for the above-mentioned crop health scenarios, improvised explosive device scenarios, or the identification and tracking of objects such as vehicles, animals or any place where a single microradio will not function properly.
[0215] It is also possible with coherent operation of the microradios to provide the aforementioned power augmentation by a factor of n 2 , where n is the number of microradios transmitting coherently, so that, for instance, ensembles of microradios, rather than having to be detected at close range, can be detected either by overflying aircraft or in some cases by satellites at 10,000 km.
Manufacture
[0216] As to the manufacturing of the microradios, they can be manufactured on, for instance, a 200-millimeter wafer and can be chemically scribed and broken up to provide almost infinitesimally small particles that are then distributed in a slurry, aerosol spray, or a paint or other coating containing microradios and are used to coat an object for which information is desired.
[0217] The use of a wafer, photolithographic patterning and etching techniques provides the 10-micron structures that, when made, can be pre-programmed with serial numbers during the manufacturing process.
[0218] More particularly, the radios are printed on a wafer using conventional semiconductor processing techniques. Scribing lines are printed on the wafer to delineate each microradio. A chemical etches through each scribing line to break up the wafer into small radio particles. The particles are then coated with a thin conducting layer. By pouring the particles on a conducting surface, the microcontroller inside each radio can receive a programming signal to load the serial number or perhaps other data or software inside the microradio control unit. In this manner, the identity of each particle is known. It would also be possible to program the radio serial number at the time of semiconductor printing. However, in this case, changing the radio data requires fabrication of a new reticle which is likely more expensive than programming the particles on a conducting plate.
[0219] Referring now to FIG. 26 , in one embodiment each radio 530 is sized to transmit ten microwatts: storage capacitor drives size. A radio contains a storage capacitor and less than 10,000 CMOS components. Using 50 nm CMOS, each radio is <20 micrometers. 10,000 radios fit along each axis of a 200 mm wafer. 100 million radios are obtained from a single $100 wafer. Each radio may cost one micro-dollar.
[0220] Here the wafer 532 is cut into 100 million components 530 , one of which is shown in FIG. 27 . Each part is coated with a conductive adhesive. Coated radios are dissolved in dilute grease or aerosol. The surface tension of the coating creates a spherical shape. In the coating procedure the wafer element is coated in SiO 2 or other insulator except for antenna coupling spots. Next, the wafer is coated with conductive adhesive.
[0221] Placement techniques for the radio particles of the present invention include UAV aerosol, munition aerosol, and manual grease.
Methods for Tracking Metal Objects Using Microradios
[0222] In the aerosol placement technique of FIG. 24 , a preferably large aircraft flies upwind. The aircraft releases smaller guided UAV or pod able to home on specific coordinates the pod sprays aerosol at the target. Remote commands will then verify successful radio placement. After a radio is charged, it radiates a coded pulse to demonstrate successful operation. Conventional geolocation processing may be employed to verify radio location. Applicable techniques including angle-of-arrival determination using an antenna array, a swept beam or monopulse processing, and ranging using time of arrival estimation among many other possible geolocation techniques.
[0223] Manual application of radio grease allows the radio grease to coat metal objects, vehicles, and other equipment. The microradios are powered by ambient RF for long-range polling.
[0224] Referring to FIG. 28 , parasitic energy extraction and storage is illustrated. Here a resonator 534 is coupled to a four-diode rectifier 536 output to a capacitor 538 . High-dielectric parallel plate capacitors are fabricated using BaTiO 3 . The size is about 10×10×10 μm. Parasitic energy extraction will be most efficient. Alternatively solar or remotely beamed energy charging could be incorporated. Other means are possible if very low duty cycle operation is required.
[0225] It will be understood that electromagnetic coupling is effected in some applications of the present invention by a microscopic device functioning as electrode, not as a radiating element. The microscopic device is physically or capacitively coupled to a macroscopic body such as a metal antenna, metal object, or a lossy dielectric, e.g. a mammal. While the isolated microradio antenna gain is proportionate to (d/λ) 2 which could be −80 dBi or less, coupled parasitic microradio gain ranges from typically −10 to +10 dBi depending on where the microradio is placed.
[0226] Note that encapsulation may be accompanied by one of two modes, which are a nonvolatile mode and a volatile mode.
[0227] Referring to FIG. 29 , in the nonvolatile mode, micro-radios are dissolved into a material, and a permanent coating is applied to a surface. The surface may be, for example, metal, plastic or skin. To manufacture such a radio, aerosol radios are diluted in preferably non-toxic solvent that is mixed with aerosol propellant. The resulting mixture is placed in pressurized vessel: aerosol can 540 , UAV sprayer or similar housing having a liquefied gas/propellant mixture 542 , a dip tube 544 that goes through a seal 546 to a nozzle 548 . Radios are the same size as floating dust particles or fog droplets (5-40 μm). The solvent evaporates on contact leaving a sparse radio coating. Each radio is sized to transmit microwatts.
Authentication
[0228] It will also be understood that the method and apparatus of the present invention can also be used to authenticate documents, objects or people. A polling device transmits a secure coded waveform and possibly a charging signal to power up the radio particle. The radio particle responds to the secure code waveform with its serial number. Comparing the serial number to the secure database authenticates the item. Currency scanners can be developed using the same technique.
[0229] In all cases, shared key encryption is needed to prevent a third party from pirating the polling waveform.
[0230] Referring to FIG. 30 , in the volatile mode a box 548 contains painted article 550 . The article is painted with a paint or other coating containing microradios to enable remote identification and authentication. At the same time, the container is sealed and floating in the air inside the container is a high vapor pressure solvent containing small radio particles. In this case, opening the box releases microradio vapor onto an intruder for tracing and attribution.
Coding
[0231] It will be appreciated that burst communication may be accomplished by means of the method and apparatus of the present invention. 50 nm CMOS logic provides ample space for transistors with, for example 100 transistors per square micrometer. Digital logic provides enhanced functionality by means, for example, of timers, decoders, waveform generators.
[0232] Referring to FIG. 31 , covert tagging and tracking may also be accomplished by means of the method and apparatus of the present invention, wherein each radio contains a unique 30-100+ digit serial number and access code. Radios only respond to messages containing correct access code from an access code generator 560 coupled to a transmitter 562 and to antenna 564 , and appropriate address fields which enable tracking down to an individual microradio. The subject system also enables sorting into user-defined radio groups as shown by microradio ensembles 566 and 568 .
Monitoring
[0233] Referring to FIG. 32 , the use of the method and apparatus of this invention to monitor sensitive objects may also be accomplished. For example, a container 570 may be provided with a spray-on biohazard container lid 572 . Container lids 572 contain adhesive radios 574 . Container 570 may contain volatile radios 576 for sealed containers. Polling container serial numbers verifies that biohazards are still safely stored. Polling enclosure numbers will detect presence of radios on skin and clothing of personnel 578 who opened sealed containers. Such tagging may be applied, for example, to hazardous containers.
Tracking of Animals and Objects
[0234] Referring to FIG. 33 , those skilled in the art will appreciate that it would be desirable to implant very small radios directly onto the bodies of animals in order to track their whereabouts. On first look, the 20-micrometer particle size makes detection of an embedded radio extremely difficult.
[0235] 2 GHz is a desirable communication frequency for radios 580 embedded in an animal 582 . It is important to model the body as a dielectric lossy conductor in order to understand communication link parameters associated with communicating with animals. 2 GHz has been found to be a good compromise between the losses incurred in the body at lower frequencies and the loss of efficiency of the rectifying diodes at higher frequencies.
[0236] The communications protocol operates similarly to radio frequency identification tags. A polling signal 584 from a transmitter 586 charges the device. It may also be possible to charge the device from ambient radiation, especially in urban areas. Upon detecting the polling signal, the radio responds with a short transmission burst 590 . This burst contains enough data to identify the serial number of embedded radio. This serial number is indexed into a data base in order to identify the carrier of the embedded radio particle.
[0237] It will also be understood that other tracking applications may be easier to implement due to shorter range requirements. In these cases, more power is available to poll the particle in order to power the radios and to receive identification bursts. The four examples shown are provided as initial applications. They are not all-inclusive.
[0238] Referring to FIG. 34 , the method and apparatus of the present application may also be used to track metal objects such as a watch 592 . The paint or other coating containing microradios spray 594 described above will covertly tag and track virtually any metal object. Chemicals added to the spray can microscopically weld the radios into the metal without visual alteration. After spraying the object, polling it via signal 596 logs the serial numbers of particles embedded on the metal by emitted signals received at 600 . The serial numbers are stored in a database at 602 for future reference. Thus, for instance, if metallic objects are uncovered in other locations, polling it can trace the source. This information can help uncover security problems.
[0239] As illustrated at FIG. 35 , at border crossing and other security gates 610 , radio polls involving a polling transceiver 614 identify vehicles 612 well in advance of the actual encounter. Alternatively, polling antennas 614 placed several kilometers along the road will provide guards with specific details of impending threats.
[0240] Harbor security is enhanced in a manner similar to other border crossing. A ship-mounted polling system can identify high-threat vessels approaching coastal areas including urban harbors with vulnerable targets for terrorist acts. Shipping containers can also be tagged.
[0241] Other metal objects to be tracked in this manner include vehicles, machinery and chemical storage containers. This method can be used to inexpensively label products in which a paint or other coating containing microradios spray is applied to a foil patch imprinted on the package.
[0242] A recent experiment showed that a microprobe effectively coupled into a metal object provided substantially more gain than free space radiation of the same microprobe. The probe injected a 1 mW 3 GHz current into an aluminum case. Received power was −69 dBm, 7 dB more than was received from the isolated probe.
[0243] As part of the subject invention, a method is described in which microradios are implanted in or on an object to be authenticated.
Embedding
[0244] The method and apparatus of the present invention may also be used in embedded sensors. Currently, many organizations are developing nanometer-scale sensors for measuring and detecting physical, chemical and biological quantities. Examples include chemical sensors as, for example, for Na, Cl, organics and inorganics; physical sensors, as, for example, for stress, strain, pressure, voltage and charge; and biological sensors as, for example, viruses, bacteria, cancer cells and DNA. In each case, the small size of the sensor creates a problem in transmitting to and receiving from the sensor. Attaching a radio particle solves this problem by enabling remote access to the sensor. The radio particle provides batteryless power through its charging circuit, commands and other input information through its receiver and a sensor data downlink through its transmitter to transmit sensor data from remote locations.
Measuring Flow in Nonmetallic Pipes or in Humans or Animals
[0245] Referring to FIG. 36 , a nonmetallic pipe 620 includes a liquid 622 in which are entrained microradios 624 that produce emissions when irradiated by energy from, for instance, a horn antenna 626 coupled to a transmitter 628 , which is used to parasitically power the microradios in the fluid that is moving along the pipe in the direction of arrow 630 . By so doing and utilizing emitter location and visualization techniques, one can determine fluid flow and indeed properties of the fluid as it moves within the nonconducting pipe.
[0246] Thus it will be understood that the method and apparatus of the present invention can be used for imaging flow in nonmetallic pipes. Emitter Location and Visualization Systems (ELVIS) techniques can locate a radio source to one-quarter wavelength. Using current NEMS technology to build a highly stable and miniature oscillator, one can anticipate building a 3 GHz device in the near term. This corresponds to 25 mm ELVIS resolution. Dissolving radio particles in a fluid would make it possible to image the particles to this resolution as they flowed through a pipe. Time-dependent imaging would provide flow measurement inside the pipes, thereby providing non-invasive flow measurement and blockage identification.
[0247] This technique also applies to mammals and humans. ELVIS can monitor and measure digestion, blood flow and air flow using radio particles. It could provide a far less expensive alternative to cardiac catheterization, a hospital procedure used to measure blood flow and to detect blockages in coronary arteries. About 100,000 cardiac catheterizations are performed annually, each costing about $20,000.00.
[0248] Future nano-electromechanical systems (NEMS) resonators are predicted to increase the transmission frequency to at least 15 GHz, providing 5 mm resolution.
Treating Diseases Including Cancer
[0249] Referring to FIGS. 37 and 38 , the present invention also encompasses a method for treating cancer. In this method a receptor molecule 700 that may be referred to as a biomarker as is described by U.S. Pat. No. 5,728,579 which is attached to a microradio 702 , which is preferably a radio particle as is described herein that is also equipped with a capacitor and a switch. Receptor molecules and microradios are injected into a human body 704 , after which the receptor molecule attaches to a malignant protein 706 , also known as a cancer marker, on a malignant tumor. There is a controller 708 outside the body that is connected to the microradio by a wireless link using transmitter 710 and antenna 712 . The microradio is attached to the malignant protein. As shown in FIG. 38 , the controller goes through a charge phase, a poll phase and a fire phase, which causes the microradio and capacitor combination to discharge current to the malignant tumor to reduce the size of and eventually eliminate the tumor.
[0250] In summary, the techniques of high-density fabrication of micro-sized radios coupled with encoding during manufacturing and distributing via liquid or aerosol, together with the use of a hysteresis switch and various types of gain-enhancing antennas, result in the ability to massively deploy a large number of almost invisible microradios that act in concert to provide enough range to be useful for a wide variety of applications.
[0251] Regardless of how power is parasitically supplied to the microradios, what is important is to deploy an ensemble of radios, charge them, radiate back coherently from them and detect their signatures, including the information that is encoded in the microradio.
[0252] Note, if multiple microradios are made to operate in a coherent fashion, then there is an n 2 power advantage to give the ensemble of microradios ranges that exceed 10,000 kilometers such that these radios can be heard by satellites.
[0253] It will be noted that if all or selected numbers of the radios are made to operate in a coherent fashion, then one has the n 2 power advantage. It has also been found that multiple coherently driven radios can be separately demodulated utilizing multi-user detection techniques in which radios operating on the same frequency with the same modulation type can have their transmissions separated out so that the information on each of the signals can be separately demodulated and understood.
[0254] Because of the use of so many microradios over a given area, antenna matching is not a problem, whereas exotic antenna materials such as ferromagnetically loaded loops can be used to increase the gain of the microradios.
[0255] Such ensembles of microradios can be used to authenticate a document or item where microradios can be embedded in the document or item, and scanned, for instance, only two inches away. When scanning close in, one mitigates free-space loss, such that if there is, for instance, one kilowatt shining towards the ensembled radios, the efficiency of the radios is not at issue.
[0256] For interrogation at a distance the techniques described herein permit remote powering and polling by, for instance, overflying at 100 feet with a high-power transmitter.
[0257] Moreover, optimal charging cycles help power the radios, with simultaneous charging at different frequencies permitting a better concentration of power to exceed diode thresholds.
[0258] The microradios may be used, for instance, in object identification when dispersed over natural radiative structures, and can be used for anti-piracy by coating valuable objects with paint or other coating containing microradios. For instance, expensive watches can be coated with microradios. Microradios can also be used to tag animals.
[0259] Moreover, shared key encryption can be used in which the interrogation key must be present in order to read out the information from the microradios.
[0260] Further, tracking can be achieved at choke points or by specialized readers in some instances.
[0261] Note that packaging can be overprinted with radio ink, or containers can be coated with encrypted microradio material. Additionally, microradios can be embedded in the material itself so that they can be detected no matter where used. Authentication is also possible through polling for specific RP signatures and multi-user detector technology can be used to separate out returns from different radios operating on the same frequency.
[0262] The microradios are so small they can be used in measuring fluid flows in large pipes or in small structures such as arteries, e.g., for venograms or echocardiograms; and can be used in drug delivery systems in which tagging molecules are provided with microradios that cause local drug release upon activation.
[0263] While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications or additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims. What is claimed is:
|
A microradio is provided with a hysteretic switch to permit an optimum range increasing charging cycle, with the charging cycle being long relative to the transmit cycle. Secondly, an ensemble of microradios permits an n 2 power enhancement to increase range with coherent operation. Various multi-frequency techniques are used both for parasitic powering and to isolate powering and transmit cycles. Applications for microradios and specifically for ensembles of microradios include authentication, tracking, fluid flow sensing, identification, terrain surveillance including crop health sensing and detection of improvised explosive devices, biohazard and containment breach detection, and biomedical applications including the use of microradios attached to molecular tags to destroy tagged cells when the microradios are activated. Microradio deployment includes the use of paints or other coatings containing microradios, greases and aerosols. Moreover, specialized antennas, including microcoils, mini dipoles, and staircase coiled structures are disclosed, with the use of nano-devices further reducing the size of the microradios.
| 8
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This disclosure is a divisional application of U.S. patent application Ser. No. 11/966,009, filed on Dec. 28, 2007, which claims the benefit of U.S. Provisional Application No. 60/883,150, filed on Jan. 2, 2007. The disclosure of the above application is incorporated herein by reference in its entirety.
FIELD
The present disclosure relates to nonvolatile memory and more particularly to interfaces for multi-level nonvolatile memory.
BACKGROUND
The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
The density of solid-state memory devices is increasing as more bits of user data can be stored into each solid-state storage element. For example, flash memory devices may store two bits per storage element by varying the stored charge in the storage element to one of four (2 2 ) levels in order to produce one of four threshold voltages. Currently, storing even more bits (such as three or four) per storage element is being investigated.
Other solid-state storage elements, such as those used in phase-change memory (PCM) devices, may store data as varying levels of resistance. Regardless of the storage mechanism, optimum spacing of the different levels may take into account the uncertainty of writing and/or reading each level. For example, within the range of achievable levels, two or more predefined levels may be established. The term level may include a voltage, a current, a resistance, or any other suitable storage parameter. The range of achievable levels is defined by a lower limit and an upper limit, which may be governed by process parameters. To write data, the storage element is programmed to one of the predefined levels. To read data, the level of the storage element is compared to the predefined levels.
There may be variability or uncertainty in reading or writing the level of a storage element. For example, when writing a first predefined level, the actual level achieved may be slightly above or below the first predefined level. This may be the result of, for example, programming the storage element using an open-loop process that is not calibrated perfectly. Alternatively, even if a closed-loop process is used, the first predefined level may be overshot or undershot. For example, this may occur when, during the last programming iteration, the programming granularity is greater than the difference between the current level and the first predefined level.
In addition, even if the first predefined level is written precisely, the level read may not be exactly equal to the first predefined level. For example, the level of the storage element may decay or shift with time. In addition, noise, crosstalk, and/or uncertainty in the reading process may lead to a slightly different level being read. A probability density function may be defined that represents the likelihood of a certain level being read a predetermined time after a predefined level is written.
FIG. 1 is a graphical representation of exemplary probability density functions (pdfs) for a four-predefined-level write scheme. In this example, the four predefined levels, L0, L1, L2, and L3, have corresponding pdfs with approximately the same shape. For example, when predefined level L0 is written, FIG. 1 indicates that the actual level achieved is most likely L0. However, it is only slightly less likely that the level achieved is slightly above or below L0. The probability of a resulting level decreases as it gets further from L0.
It may be desirable to space the predefined levels so that each pdf ends (drops to zero) before the next pdf begins, as shown in FIG. 1 . For example, this may ensure that a level on the high side of the level L1 pdf is not misinterpreted as a level on the low side of the level L2 pdf. The predefined levels L0, L1, L2, and L3 may therefore be arranged so that their pdfs do not overlap. When the pdfs for various levels are approximately the same, the predefined levels may be uniformly spaced to achieve this goal.
FIG. 2 depicts exemplary pdfs for a four-predefined-level write scheme when the pdfs differ. For example, in FIG. 2 , the L0 pdf is wider (has a greater standard deviation) than that of L1, L2, and L3. There are various reasons why pdfs may be different for different levels. For example, L0 may be an erased level, which cannot be controlled as accurately as programmed levels. Other process variability or design considerations may affect the size and shape of the pdfs.
To accommodate the widened level L0 pdf, predefined levels L1 and L2 may be moved slightly higher and closer to each other, as shown in the example of FIG. 2 . As more levels are introduced, the proximity of the pdfs may increase, and it may not be possible to avoid overlap between the pdfs. Error control coding may be used, which may identify and/or correct errors resulting from misreading of a previously written level.
Referring now to FIG. 3 , a functional block diagram of a memory system according to the prior art is presented. A memory controller 100 interfaces with a memory chip 102 . For a write, the memory controller 100 sends user data to the memory chip 102 along with an address to which the user data should be written. The memory controller 100 may also indicate to the memory chip 102 that a write is desired using a read/write signal. The memory chip 102 converts the user data into predefined levels for each storage element that will be written. The memory chip 102 then writes the predefined levels to the storage elements at the designated address.
During a read, the memory controller 100 requests a read from the memory chip 102 and provides an address. The memory chip 102 measures the levels of the storage elements at the given address. These levels are matched up with the closest predefined levels, which are then mapped back to user data. The user data is returned to the memory controller 100 . For example, with reference to FIG. 2 , if a threshold voltage slightly above predefined level L3 is measured from a charge storage cell, the memory chip 102 decides that predefined level L3 had previously been written.
Predefined level L3 may correspond to a bit pattern of 11, which the memory chip 102 then returns to the memory controller 100 . The values of the predefined levels and data/level mappings are determined at design time and hard coded into the memory chip 102 . The memory controller 100 does not need to be aware of any level information, simply transmitting binary user data to the memory chip 102 and receiving binary user data from the memory chip 102 .
SUMMARY
In general, in one aspect, this specification describes a memory chip including a plurality of storage elements, a receiver and a program module. Each of the storage elements has a measurable parameter. The receiver receives N target values from a memory controller, where N is an integer greater than zero. The programming module adjusts corresponding measurable parameters of N storage elements of the plurality of storage elements to the N target values.
Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIG. 1 is a graphical representation of exemplary probability density functions (pdfs) for a four-predefined-level write scheme;
FIG. 2 is a graphical representation of exemplary pdfs for a four-predefined-level write scheme when the pdfs differ;
FIG. 3 is a functional block diagram of a memory system according to the prior art;
FIG. 4 is a functional block diagram of an exemplary memory controller that sends and receives digital data representing level information to a memory chip;
FIG. 5 is a functional block diagram of an exemplary memory controller that communicates with the memory chip using an embedded clock;
FIG. 6 is a functional block diagram of an exemplary memory controller that transmits digital write information to a memory chip and receives analog read information;
FIG. 7 is a functional block diagram of an exemplary memory controller that sends analog write data to a memory chip and receives analog read data;
FIG. 8 is a functional block diagram of an exemplary system where deskewing circuitry is moved to a memory controller from memory chips;
FIG. 9A is a functional block diagram of a hard disk drive;
FIG. 9B is a functional block diagram of a DVD drive;
FIG. 9C is a functional block diagram of a high definition television;
FIG. 9D is a functional block diagram of a vehicle control system;
FIG. 9E is a functional block diagram of a cellular phone;
FIG. 9F is a functional block diagram of a set top box; and
FIG. 9G is a functional block diagram of a mobile device.
DETAILED DESCRIPTION
The following description is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses. For purposes of clarity, the same reference numbers will be used in the drawings to identify similar elements. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A or B or C), using a non-exclusive logical or. It should be understood that steps within a method may be executed in different order without altering the principles of the present disclosure.
As used herein, the term module refers to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.
The prior art describes predefined levels for storage elements that are set at design time. Newer and emerging multi-level memory technologies may have level probability density functions (pdfs) and optimum level choices that are not fully characterized at design time. For example, characteristics that influence level determinations may vary across manufacturing lots, from wafer to wafer, or even across a single wafer. In addition, these characteristics may change with time and with the number of program or, erase cycles that a storage element sustains.
Determining these characteristics may be accomplished using intelligent firmware, mapping tables, and/or digital signal processing. These characteristics may relate to the pdf of what level is read when a defined level will be written. When a defined level is likely to be misread, it may need to be spaced further away from other defined levels. For example, for a storage element that stores 2 bits, 4 defined levels may be defined, where one defined level is spaced further away from the other three defined levels. As the memory chip wears, fewer defined levels may be used and/or spacing between the levels may be increased. In addition, the defined levels may be determined and implemented differently across different areas of a memory chip.
Instead of replicating the capability to determine and use defined levels in each memory chip, a single memory controller may perform some or all of these functions. By locating level control in the memory controller, multiple memory chips do not each have to have this functionality. In addition, fabricating structures for level control, such as mixed signal and/or digital signal processing structures, in the memory chips may require more complex fabrication processes. Moving level control circuitry to the memory controller may decrease the types of devices that need to be fabricated in the memory chip. When memory chips primarily include storage elements, process steps required for other devices may be eliminated, thereby decreasing the cost of memory chips.
In addition, a memory controller may include storage for firmware and an interface for updating the firmware. Replicating this firmware in each memory chip may increase the cost over a single memory controller including the firmware storage. In addition, adding a firmware interface to each memory chip may add increased cost to the memory chip and/or to the cost of the printed circuit board on which the memory chip is located and may introduce signal integrity problems.
In the prior art, a memory controller provides user data to the memory chip, which then translates the user data into predefined levels. According to the principles of the present disclosure, a memory controller may determine optimum defined levels and may send the actual level information to the memory chip. In addition, during a read, the measurements of storage elements may be relayed to the memory controller. The memory controller may apply more advanced processing to extract valid data. This is in contrast to the memory chip making hard decisions based on the measurements and returning sometimes incorrect user data.
FIG. 4 depicts an approach where the memory controller transmits digital data to the memory chip indicating programming parameters to program a storage element to a defined level. For example, the memory controller may receive user data, which can be represented in a storage element as a first defined level. The memory controller will then provide programming parameters to the memory chip that will cause a storage element in the memory chip to reach the first defined level.
For example, the first defined level may define a first quantity of charge in a charge-storage-based storage element, which will result in the storage element having a first threshold voltage. The programming parameters the memory controller provides may include a programming voltage and/or a programming time that will raise the quantity of charge in the storage element to the first quantity. The memory chip may then program the storage element at the specified programming voltage for the specified programming time.
To perform a read, the memory chip measures the level of the storage element. For example, the memory chip may apply a voltage to the storage element, and measure the resulting current. This may be an indication of the threshold voltage of the storage element, which indicates the amount of charge stored in the storage element.
The memory chip of FIG. 4 converts the measured value into a digital value, which is returned to the memory controller. This digital value is not a hard decision on what user data was stored, but instead represents the level that was read. The memory controller can then process this information to determine which defined level was originally written, which is then mapped to user data.
FIG. 5 depicts a system similar to that of FIG. 4 , except that a separate clock used to transfer digital data between the memory controller and memory chip is eliminated. Instead, an embedded clock is used along with clock recovery. FIG. 6 is a system where the memory chip does not include an analog to digital converter. Accordingly, the memory chip returns an analog value to the memory controller, which then converts that value to digital form.
Due to the complexity, mixed signal requirements, and layout space, moving the analog to digital converter to the memory controller may save money on each memory chip that is used in the system. In FIG. 7 , the digital to analog converter is relocated to the memory controller. The memory controller therefore sends analog write information and receives analog read information. Address information may still be sent digitally, as shown in FIG. 7 .
FIG. 8 shows an exemplary implementation of clock deskewing in the memory controller. By varying the delay in digital signals sent to the memory chip, the clock received by memory chip can be used directly to latch data. For example, in FIG. 8 , the memory controller includes a delay module for each of the memory chips to align data for each of the chips with the clock. FIGS. 9A-9G depict exemplary devices in which memory controllers and chips according to the present disclosure may be used.
Referring now to FIG. 4 , a memory controller 202 that sends and receives digital data representing level information to a memory chip 204 is presented. The memory controller 202 includes a control module 210 . The control module 210 receives access (read and write) requests from a host (not shown).
The control module 210 outputs address and data information to a multiplexer 212 and a write level module 214 . For address information, the multiplexer 212 outputs the address information from the control module 210 to a high-speed modulator 216 . When the control module 210 outputs data, the write level module 214 may convert user data into digital level data. The multiplexer 212 then outputs this digital level data to the high-speed modulator 216 . The write level module 214 may store a mapping table, received from the control module 210 , of user data to programming parameters for defined levels.
The programming parameters may include programming voltages/currents, programming times, programming pulse widths, etc. Additionally or alternatively, the programming parameters may include a desired storage element parameter. This may be used as a target for open-loop or closed-loop programming. For example, when using a charge storage element, the desired storage element parameter may be a desired threshold voltage or a desired current at a predetermined read voltage. For example, when using a phase-change storage element, the desired storage element parameter may be a desired resistance.
The high-speed modulator 216 converts the received information into a serial stream, which is output from the memory controller 202 by a line driver 218 . The high-speed modulator 216 may include a serializer, which may be implemented as part of a serializer/deserializer, and may include a high-speed multi-bit link. A signal conversion module 230 in the memory chip 204 receives the data from the line driver 218 . The data from the line driver 218 may be carried by a low voltage differential signaling (LVDS) interface, and the signal conversion module 230 may include a differential amplifier.
The memory chip 204 includes a latch 232 , which latches an output of the signal conversion module 230 based on a received clock signal. The received clock signal may be interpreted by a deskewing module 234 . The deskewing module 234 may include, for example, a delay locked loop, a phase locked loop, and/or a calibrated delay element.
An output of the latch 232 is received by a high-speed demodulator 236 . The high-speed demodulator 236 may include a deserializer, which may be implemented as part of a serializer/deserializer, and may include a high-speed multi-bit link. The high-speed demodulator 236 outputs address and data information. Indication of whether the information is address or data may be included in the serial stream or may be indicated by sideband data, such as a separate control line or bus. Address information may be received by a digital buffer 238 . The buffer 238 then presents one or more addresses to a memory array 240 for reading or writing.
Data information may be received by a digital to analog converter (DAC) 242 . The data information may include one or more programming parameters for programming a storage element of the memory array 240 to a desired level. The DAC 242 applies an analog version of the received digital value to the memory array 240 .
If multiple storage elements will be programmed in the memory array 240 at the same time, a buffer (not shown) may be inserted between the DAC 242 and the memory array 240 . The buffer can then accumulate analog values from the DAC 242 and present them to the memory array 240 for programming. Additionally or alternatively, multiple instances of the DAC 242 may produce analog output values in parallel.
The analog values may represent target values, such as target threshold voltages or target resistances. In various implementations, instead of being measured directly, these values may be inferred from values such as measured currents or measured voltages. These values may be measured when a known voltage or current is applied to the cell.
In open-loop programming, these values may not be measured until the storage element is read. In closed-loop programming, these values may be measured after each iteration of programming. Closed-loop programming may complete once the measured value differs from the target value by less than a predetermined amount. This predetermined amount may be, for example, a percentage or an absolute value. The predetermined amount may be proportional to the maximum number of defined levels in the storage element. For example, if there are up to four defined levels for a measured parameter of a storage cell, the predetermined amount may be a predetermined percentage of a quarter of the possible range of the measured parameter.
During a read, the buffer 238 presents the address to the memory array 240 . The memory array 240 outputs analog values to an analog to digital converter (ADC) 244 . The memory array 240 may output multiple analog values from multiple storage elements to multiple instances of the ADC 244 . In various other implementations, the memory array 240 may output in sequence a number of analog values to the ADC 244 . Each of these values may be produced by a new address received from the buffer 238 , or may be output based on logic internal to the memory array 240 .
The ADC 244 outputs digital values to a high-speed modulator 246 . An output of the high-speed modulator 246 is output to the memory controller 202 via a line driver 248 . In various implementations, the serial link between the memory controller 202 and the memory chip 204 may be multiplexed between transmitting write data to the memory chip 204 and returning read data to the memory controller 202 .
While receiving write data, the line driver 248 may be tristated—i.e., its output placed into a high impedance state. Similarly, while receiving read data, the line driver 218 may be tristated. If duplex operation is desired, the line driver 248 may output read data to the memory controller 202 via a second serial link. If greater throughput is desired, a separate serial link may be added for address information, while the original serial link is used for data information. In addition, the system of FIG. 4 may support various forms of burst mode, such as where a single address is sent followed by multiple pieces of data for that and subsequent addresses.
Data output by the line driver 248 is received by a signal conversion module 260 in the memory controller 202 . The signal conversion module 260 may include a differential amplifier, which outputs data to a high-speed demodulator 262 . The high-speed demodulator 262 outputs digital values from the memory chip 204 to the control module 210 . These digital values may indicate the levels read from storage elements in the memory array 240 . For example, the digital values may represent threshold voltages of storage elements. Alternately, the digital values may represent measured currents, which may be converted into threshold voltages.
The control module 210 interprets the received values to recover the user data that had been stored in the memory array 240 . For example, the control module 210 may have a mapping for each of the connected memory chips, including the memory chip 204 . For example, each mapping may be from user data to defined threshold voltages. The control module 210 may recover the user data by identifying which one of the defined threshold voltages is closest to the received threshold voltage. The mapping is then used to determine the user data corresponding to the identified threshold voltage.
The control module 210 may be programmed with level information for the memory chip 204 at the time of assembly. For example, the memory chip 204 , or the lot or wafer from which the memory chip 204 is taken, may be characterized. Characterization may determine how many defined levels can be stored in storage elements of the memory chip 204 and how closely spaced each of the defined levels should be. The values from calibration may be stored into firmware of the memory controller 202 after the memory controller 202 and the memory chip 204 are placed on a circuit board.
In various implementations, there may be a number of discrete levels available. For example, a phase-change storage element may include two phase-change regions, each of which may be in a crystalline or non-crystalline state. The phase-change storage element may then offer four discrete resistances based on the state of each phase-change region. Characterization may involve determining whether each of the discrete levels is achievable. Characterization may also include determining the programming parameters used to program the storage elements to each of the discrete levels.
Additionally or alternatively, the control module 210 may itself perform characterization. This may be performed upon power on, at times specified by the host, and/or at periodic intervals during use of the memory chip 204 . For example, the control module 210 may perform characterization by writing and reading test values to determine optimum levels.
Characterization may result in a mapping table that maps each value of user data to a defined level and one or more associated programming parameters. The control module 210 may store a mapping table for each connected memory chip, including the memory chip 204 . The control module 210 may also store multiple mapping tables corresponding to different areas of the memory chip 204 . For example, for memory blocks that have higher error rates, the control module 210 may store a mapping table including fewer defined levels. The control module 210 may use error control coding to protect data written to the memory chip 204 . The control module 210 may also adapt mapping tables based on error rates, changing the defined levels in the mapping table until data stored using that mapping table experiences a lower error rate.
Storage elements may degrade and/or experience changes in properties as the number of erases, writes, and/or reads increases. For example, the control module 210 may store mapping tables for different numbers of erases. When data is written to storage element, the number of erases the storage element has experienced determines the mapping table used. The mapping table or tables may be sent to the write level module 214 , which can subsequently translate each write request into appropriate programming parameters.
The memory controller 202 includes a clock generator 264 , whose output is driven to the memory chip 204 using a line driver 266 . The dedicated clock signal may allow for rapid power-up and power-down of the memory chip 204 . The clock may also be used by the memory controller 202 to receive data from the memory chip 204 . The clock generator 264 may further generate one or more clocks for other components of the memory controller 202 . For example, a latch (not shown) similar to the latch 232 of the memory chip 204 may be implemented in the memory controller 202 between the signal conversion module 260 and the high-speed demodulator 262 .
The memory chip 204 may also include a write calibration module 270 . For example, in phase-change memory (PCM), write calibration may be performed within the memory chip 204 . The write calibration module 270 may output address data to the buffer 238 and level information to the DAC 242 and may receive read information from the ADC 244 . In implementations where the memory chip 204 does not include the write calibration module 270 , the ADC 244 may not be required and may be moved to the memory controller 202 , as shown in FIG. 6 .
Referring now to FIG. 5 , a memory controller 302 that communicates with a memory chip 304 using an embedded clock is depicted. The memory controller 302 includes a high-speed modulator 310 that receives the output of the multiplexer 212 . The high-speed modulator 310 may include clock and coding circuitry that encodes a clock signal into the bits to be transmitted. For example, the high-speed modulator 310 may use a line code, such as Manchester coding, 8B/10B, or non-return-to-zero. The line driver 218 then drives the signal to the memory chip 304 .
The signal is received by the signal conversion module 230 . The signal is also received by a clock recovery module 312 . Alternatively, the clock recovery module 312 may receive the output of the signal conversion module 230 . The clock recovery module 312 recovers the embedded clock and outputs the recovered clock to the clock input of the latch 232 .
When transmitting read data to the memory controller 302 , a high-speed modulator 320 in the memory chip 304 may use the clock recovered by the clock recovery module 312 . Alternatively, the high-speed modulator 320 may embed the recovered clock or another clock into the data. The memory controller 302 includes a high-speed demodulator 322 , which may extract a clock embedded by the high-speed modulator 320 . Alternatively, the high-speed demodulator 322 may use the clock from the clock generator 264 of the memory controller 302 .
Referring now to FIG. 6 , a memory controller 402 that transmits digital write information to a memory chip 404 and receives analog read information is shown. A control module 410 in the memory controller 402 outputs user data to the write level module 214 and address information to the multiplexer 212 . The write level module 214 converts user data into digital programming parameters for storing a defined level corresponding to that data.
The output of the write level module 214 is sent to the high-speed modulator 216 . The memory controller 402 outputs serialized digital information via the line driver 218 . This information may be data information to be translated by the DAC 242 or may be address information. When a read is performed, the memory array 240 outputs one or more analog values to an analog line driver 420 . The analog line driver 420 outputs these analog values to an ADC 430 of the memory controller 402 .
The control module 410 receives digital data from the ADC 430 indicating the analog values read from the memory array 240 . The control module 410 then converts these values into user data. As shown in FIG. 6 , the bus between the memory controller 402 and the memory chip 404 may be multiplexed to carry both digital and analog data. However, to optimize the design for each of these types of data and/or to improve signal integrity, a separate digital bus and analog bus may be created. The analog line driver 420 could then transmit data to the ADC 430 using the analog bus.
Referring now to FIG. 7 , a memory controller 502 that sends analog write data to a memory chip 504 and receives analog read data is shown. In various implementations, such as that shown in FIG. 7 , the address data is still sent digitally. A control module 510 outputs digital address data to the high-speed modulator 216 . The digital address data is transmitted to the memory chip 504 via the line driver 218 . Alternatively, the digital address data may be transmitted to the memory chip 504 using a parallel bus.
The digital address data is applied to the memory array 240 by the buffer 238 . The analog output of the memory array 240 is transmitted to the ADC 430 of the memory controller 502 by the analog line driver 420 . The control module 510 outputs write data to the write level module 214 . The write level module 214 translates this data into digital programming parameters, which are output to a DAC 520 .
The DAC 520 converts the programming parameters into analog values that are sent to an analog buffer 524 of the memory chip 504 via a second analog line driver 528 . The analog buffer 524 may amplify the signal received from the second analog line driver 528 . In addition, the analog buffer 524 may buffer multiple analog signals, which may then be applied in parallel or sequentially to the memory array 240 .
In various implementations, a multiplexed bus may be used between the second analog line driver 528 and the analog buffer 524 and the analog line driver 420 and the ADC 430 , as shown in FIG. 6 . In various implementations, the memory chip 504 may include the ADC 430 , and output digital data to the memory controller 502 .
Referring now to FIG. 8 , a system where deskewing circuitry is moved to a memory controller 602 from memory chips 604 is shown. By including deskewing circuitry, the memory controller 602 removes the burden of deskewing from the memory chips 604 , of which three are shown, 604 - 1 , 604 - 2 , and 604 - 3 . The memory controller 602 includes the clock generator 264 and the line driver 266 , which drives the clock from the clock generator 264 to the memory chips 604 .
The memory controller 602 includes an output module 610 , which outputs data for the memory chips 604 . The output module 610 may include the write level module 214 and/or the high-speed modulator 216 of FIG. 4 and/or may include any other module in the memory controller 602 that transmits data to the memory chips 604 . The values from the output module are received by three delay modules 620 - 1 , 620 - 2 , and 620 - 3 , which correspond to the memory chip 604 - 1 , the memory chip 604 - 2 , and the memory chip 604 - 3 , respectively.
The delay modules 620 are controlled by a delay control module 630 . The delay control module 630 may receives feedback from the memory chips 604 and adjust the amount of delay introduced by each of the delay modules 620 . For example, the delay control module 630 may receive signal quality information from the latch modules 650 , and adjust the delay of the delay modules 620 until adequate signal integrity is achieved. The delay modules 620 delay the signals from the output module 610 , and these signals are driven to the memory chips 604 by line drivers 640 - 1 , 640 - 2 , and 640 - 3 , respectively.
In various implementations, the delay control module 630 may include a lookup table that stores delay values for the delay modules 620 . The lookup table may be created when the system is assembled or designed. In various implementations, the delay control module 630 may send a time-varying pattern of data to the memory chips 604 . The memory chips 604 may transmit to the delay control module 630 the values received. The delay control module 630 may use this information to determine the appropriate delay. The delay control module 630 may increase or decrease the delay by small increments for the memory chips 604 that do not return valid data.
The driven values are then latched by latch modules 650 - 1 , 650 - 2 , and 650 - 3 in the memory chips 604 - 1 , 604 - 2 , and 604 - 3 , respectively. The latch modules 650 are clocked by the clock received from the line driver 266 . By adjusting the amount of delay introduced by the delay modules 620 , the delay control module 630 can ensure that the data arrives at the latch modules 650 synchronously with the clock signal.
If memory chip 604 - 1 is located closer to the memory controller 602 , the delay introduced by the delay module 620 - 1 may be greater to offset the shorter distance to reach the memory chip 604 - 1 . While multiple delay modules adjust the data in FIG. 8 , in various other implementations, multiple delay modules may adjust the clock while a single data stream is output. In such implementations, the delay control module 630 would control the delay introduced to each clock signal, so that they are synchronously received with the data at each of the memory chips 604 .
In FIGS. 9A-9G , various exemplary implementations incorporating the teachings of the present disclosure are shown. Referring now to FIG. 9A , the teachings of the disclosure can be implemented in a buffer 711 and/or nonvolatile memory 712 of a hard disk drive (HDD) 700 . The HDD 700 includes a hard disk assembly (HDA) 701 and an HDD printed circuit board (PCB) 702 . The HDA 701 may include a magnetic medium 703 , such as one or more platters that store data, and a read/write device 704 .
The read/write device 704 may be arranged on an actuator arm 705 and may read and write data on the magnetic medium 703 . Additionally, the HDA 701 includes a spindle motor 706 that rotates the magnetic medium 703 and a voice-coil motor (VCM) 707 that actuates the actuator arm 705 . A preamplifier device 708 amplifies signals generated by the read/write device 704 during read operations and provides signals to the read/write device 704 during write operations.
The HDD PCB 702 includes a read/write channel module (hereinafter, “read channel”) 709 , a hard disk controller (HDC) module 710 , the buffer 711 , nonvolatile memory 712 , a processor 713 , and a spindle/VCM driver module 714 . The read channel 709 processes data received from and transmitted to the preamplifier device 708 . The HDC module 710 controls components of the HDA 701 and communicates with an external device (not shown) via an I/O interface 715 . The external device may include a computer, a multimedia device, a mobile computing device, etc. The I/O interface 715 may include wireline and/or wireless communication links.
The HDC module 710 may receive data from the HDA 701 , the read channel 709 , the buffer 711 , nonvolatile memory 712 , the processor 713 , the spindle/VCM driver module 714 , and/or the I/O interface 715 . The processor 713 may process the data, including encoding, decoding, filtering, and/or formatting. The processed data may be output to the HDA 701 , the read channel 709 , the buffer 711 , nonvolatile memory 712 , the processor 713 , the spindle/VCM driver module 714 , and/or the I/O interface 715 .
The HDC module 710 may use the buffer 711 and/or nonvolatile memory 712 to store data related to the control and operation of the HDD 700 . The buffer 711 may include DRAM, SDRAM, etc. Nonvolatile memory 712 may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The spindle/VCM driver module 714 controls the spindle motor 706 and the VCM 707 . The HDD PCB 702 includes a power supply 716 that provides power to the components of the HDD 700 .
Referring now to FIG. 9B , the teachings of the disclosure can be implemented in a buffer 722 and/or nonvolatile memory 723 of a DVD drive 718 or of a CD drive (not shown). The DVD drive 718 includes a DVD PCB 719 and a DVD assembly (DVDA) 720 . The DVD PCB 719 includes a DVD control module 721 , the buffer 722 , nonvolatile memory 723 , a processor 724 , a spindle/FM (feed motor) driver module 725 , an analog front-end module 726 , a write strategy module 727 , and a DSP module 728 .
The DVD control module 721 controls components of the DVDA 720 and communicates with an external device (not shown) via an I/O interface 729 . The external device may include a computer, a multimedia device, a mobile computing device, etc. The I/O interface 729 may include wireline and/or wireless communication links.
The DVD control module 721 may receive data from the buffer 722 , nonvolatile memory 723 , the processor 724 , the spindle/FM driver module 725 , the analog front-end module 726 , the write strategy module 727 , the DSP module 728 , and/or the I/O interface 729 . The processor 724 may process the data, including encoding, decoding, filtering, and/or formatting. The DSP module 728 performs signal processing, such as video and/or audio coding/decoding. The processed data may be output to the buffer 722 , nonvolatile memory 723 , the processor 724 , the spindle/FM driver module 725 , the analog front-end module 726 , the write strategy module 727 , the DSP module 728 , and/or the I/O interface 729 .
The DVD control module 721 may use the buffer 722 and/or nonvolatile memory 723 to store data related to the control and operation of the DVD drive 718 . The buffer 722 may include DRAM, SDRAM, etc. Nonvolatile memory 723 may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The DVD PCB 719 includes a power supply 730 that provides power to the components of the DVD drive 718 .
The DVDA 720 may include a preamplifier device 731 , a laser driver 732 , and an optical device 733 , which may be an optical read/write (ORW) device or an optical read-only (OR) device. A spindle motor 734 rotates an optical storage medium 735 , and a feed motor 736 actuates the optical device 733 relative to the optical storage medium 735 .
When reading data from the optical storage medium 735 , the laser driver provides a read power to the optical device 733 . The optical device 733 detects data from the optical storage medium 735 , and transmits the data to the preamplifier device 731 . The analog front-end module 726 receives data from the preamplifier device 731 and performs such functions as filtering and A/D conversion. To write to the optical storage medium 735 , the write strategy module 727 transmits power level and timing data to the laser driver 732 . The laser driver 732 controls the optical device 733 to write data to the optical storage medium 735 .
Referring now to FIG. 9C , the teachings of the disclosure can be implemented in memory 741 and/or a storage device 742 of a high definition television (HDTV) 737 . The HDTV 737 includes an HDTV control module 738 , a display 739 , a power supply 740 , memory 741 , the storage device 742 , a network interface 743 , and an external interface 745 . If the network interface 743 includes a wireless local area network interface, an antenna (not shown) may be included.
The HDTV 737 can receive input signals from the network interface 743 and/or the external interface 745 , which can send and receive data via cable, broadband Internet, and/or satellite. The HDTV control module 738 may process the input signals, including encoding, decoding, filtering, and/or formatting, and generate output signals. The output signals may be communicated to one or more of the display 739 , memory 741 , the storage device 742 , the network interface 743 , and the external interface 745 .
Memory 741 may include random access memory (RAM) and/or nonvolatile memory. Nonvolatile memory may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The storage device 742 may include an optical storage drive, such as a DVD drive, and/or a hard disk drive (HDD). The HDTV control module 738 communicates externally via the network interface 743 and/or the external interface 745 . The power supply 740 provides power to the components of the HDTV 737 .
Referring now to FIG. 9D , the teachings of the disclosure may be implemented in memory 749 and/or a storage device 750 of a vehicle 746 . The vehicle 746 may include a vehicle control system 747 , a power supply 748 , memory 749 , the storage device 750 , and a network interface 752 . If the network interface 752 includes a wireless local area network interface, an antenna (not shown) may be included. The vehicle control system 747 may be a powertrain control system, a body control system, an entertainment control system, an anti-lock braking system (ABS), a navigation system, a telematics system, a lane departure system, an adaptive cruise control system, etc.
The vehicle control system 747 may communicate with one or more sensors 754 and generate one or more output signals 756 . The sensors 754 may include temperature sensors, acceleration sensors, pressure sensors, rotational sensors, airflow sensors, etc. The output signals 756 may control engine operating parameters, transmission operating parameters, suspension parameters, etc.
The power supply 748 provides power to the components of the vehicle 746 . The vehicle control system 747 may store data in memory 749 and/or the storage device 750 . Memory 749 may include random access memory (RAM) and/or nonvolatile memory. Nonvolatile memory may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The storage device 750 may include an optical storage drive, such as a DVD drive, and/or a hard disk drive (HDD). The vehicle control system 747 may communicate externally using the network interface 752 .
Referring now to FIG. 9E , the teachings of the disclosure can be implemented in memory 764 and/or a storage device 766 of a cellular phone 758 . The cellular phone 758 includes a phone control module 760 , a power supply 762 , memory 764 , the storage device 766 , and a cellular network interface 767 . The cellular phone 758 may include a network interface 768 , a microphone 770 , an audio output 772 such as a speaker and/or output jack, a display 774 , and a user input device 776 such as a keypad and/or pointing device. If the network interface 768 includes a wireless local area network interface, an antenna (not shown) may be included.
The phone control module 760 may receive input signals from the cellular network interface 767 , the network interface 768 , the microphone 770 , and/or the user input device 776 . The phone control module 760 may process signals, including encoding, decoding, filtering, and/or formatting, and generate output signals. The output signals may be communicated to one or more of memory 764 , the storage device 766 , the cellular network interface 767 , the network interface 768 , and the audio output 772 .
Memory 764 may include random access memory (RAM) and/or nonvolatile memory. Nonvolatile memory may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The storage device 766 may include an optical storage drive, such as a DVD drive, and/or a hard disk drive (HDD). The power supply 762 provides power to the components of the cellular phone 758 .
Referring now to FIG. 9F , the teachings of the disclosure can be implemented in a memory 783 and/or a storage device 784 of a set top box 778 . The set top box 778 includes a set top control module 780 , a display 781 , a power supply 782 , memory 783 , the storage device 784 , and a network interface 785 . If the network interface 785 includes a wireless local area network interface, an antenna (not shown) may be included.
The set top control module 780 may receive input signals from the network interface 785 and an external interface 787 , which can send and receive data via cable, broadband Internet, and/or satellite. The set top control module 780 may process signals, including encoding, decoding, filtering, and/or formatting, and generate output signals. The output signals may include audio and/or video signals in standard and/or high definition formats. The output signals may be communicated to the network interface 785 and/or to the display 781 . The display 781 may include a television, a projector, and/or a monitor.
The power supply 782 provides power to the components of the set top box 778 . Memory 783 may include random access memory (RAM) and/or nonvolatile memory. Nonvolatile memory may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The storage device 784 may include an optical storage drive, such as a DVD drive, and/or a hard disk drive (HDD).
Referring now to FIG. 9G , the teachings of the disclosure can be implemented in a memory 792 and/or a storage device 793 of a mobile device 789 . The mobile device 789 may include a mobile device control module 790 , a power supply 791 , memory 792 , the storage device 793 , a network interface 794 , and an external interface 799 . If the network interface 794 includes a wireless local area network interface, an antenna (not shown) may be included.
The mobile device control module 790 may receive input signals from the network interface 794 and/or the external interface 799 . The external interface 799 may include USB, infrared, and/or Ethernet. The input signals may include compressed audio and/or video, and may be compliant with the MP3 format. Additionally, the mobile device control module 790 may receive input from a user input 796 such as a keypad, touchpad, or individual buttons. The mobile device control module 790 may process input signals, including encoding, decoding, filtering, and/or formatting, and generate output signals.
The mobile device control module 790 may output audio signals to an audio output 797 and video signals to a display 798 . The audio output 797 may include a speaker and/or an output jack. The display 798 may present a graphical user interface, which may include menus, icons, etc. The power supply 791 provides power to the components of the mobile device 789 . Memory 792 may include random access memory (RAM) and/or nonvolatile memory.
Nonvolatile memory may include any suitable type of semiconductor or solid-state memory, such as flash memory (including NAND and NOR flash memory), phase-change memory, magnetic RAM, and multi-state memory, in which each memory cell has more than two states. The storage device 793 may include an optical storage drive, such as a DVD drive, and/or a hard disk drive (HDD). The mobile device may include a personal digital assistant, a media player, a laptop computer, a gaming console, or other mobile computing device.
Memory controllers and memory chips according to the principles of the present disclosure may be used in high-performance and enterprise computing systems. Enterprise computing systems may provide services, such as file serving, database processing, and application hosting, to multiple users throughout an organization. Enterprise computing systems may be characterized by high uptime (such as 99.99% uptime), scalability, and large amounts of memory. In these situations, the benefits of the memory systems of the present disclosure, which may include reducing memory chip cost, may be amplified.
Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, the specification, and the following claims.
|
A memory chip including a plurality of storage elements, a receiver and a program module. Each of the storage elements has a measurable parameter. The receiver receives N target values from a memory controller, where N is an integer greater than zero. The programming module adjusts corresponding measurable parameters of N storage elements of the plurality of storage elements to the N target values.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority of U.S. patent application Ser. No. 61/534,615 filed Sep. 14, 2011, which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to cargo systems, and more particularly, to a universal load device fire suppression system.
[0003] Millions of dollars of aircraft and property have been lost to cargo fires developing during transportation, especially in a load device, such as a universal load device (ULD). Aircraft cargo may typically be remote from the pilot or other aircraft personnel. Consequently, there is a delay in personnel knowing of a fire in the cargo hold and a delay in being able to put the fire out. In some cases, cargo aircraft have not been able to react soon enough to get back on the ground during in-flight fires.
[0004] As can be seen, there is a need for a fire suppression system that may recognize a fire and maintain the fire within a ULD for suppression.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a perspective side view of a cargo container according to an exemplary embodiment of the present invention;
[0006] FIG. 2 is a perspective top view of a base wall of the cargo container of FIG. 1 ;
[0007] FIG. 2A is a cross-sectional side view of a liner used in a wall of the cargo container of FIG. 1 ;
[0008] FIG. 3 is a top view of base wall of FIG. 2 sans the liner;
[0009] FIG. 4 is a side exploded view of a fire suppression system that may be used in the cargo container of FIG. 1 according to another exemplary embodiment of the present invention;
[0010] FIG. 5 is a side view of the fire suppression system of FIG. 4 , mounted;
[0011] FIG. 6 is an internal front view of a control box of the fire suppression system of FIG. 4 ;
[0012] FIG. 7 is a side view of the control box of FIG. 6 ;
[0013] FIG. 8 is an exploded view of a sensor and control box of the fire suppression system of FIG. 5 without a fire suppression cylinder;
[0014] FIG. 9 is an internal rear view of the control box of FIG. 6 with an integrated battery;
[0015] FIG. 10 is a right side view of the control box of FIG. 7 ; and
[0016] FIG. 11 is a schematic diagram of an electrical circuit employed in the fire suppression system of FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
[0017] The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
[0018] Broadly, an exemplary embodiment of the present invention generally provides a fire detection and suppression system. An exemplary embodiment of the present invention provides an automatic fire detection and suppression system designed for a cargo craft to protect from a fire spreading amongst cargo containers. Another embodiment may include a liner designed to fireproof cargo containers so that if a fire occurs within a container, elements outside the container are protected. Also, if a fire occurs outside the container, the contents of the container may be protected from the exterior.
[0019] Referring now to FIG. 1 , a cargo container 8 is shown according to an exemplary embodiment of the present invention. The cargo container 8 may be for example, a universal load device (ULD). The cargo container 8 may include, for example, steel walls and framing. The cargo container 8 may include a fire extinguisher 304 mounted inside a recessed mounting cabinet 305 . In some embodiments, the extinguisher 304 may be protected behind a door of the cabinet 305 . The cargo container 8 may include a roll-up type stainless steel door 303 allowing easy access to the interior. The cargo container 8 may also include a check valve 302 to relieve at least some pressure from within the cargo container 8 , which may maintain a positive fire extinguishant environment. The check valve 302 may allow suppression gases to stay within while atmospheric gases are expelled. While the check valve 302 is shown on a roof of the cargo container 8 , it will be understood that the check valve 302 may be placed on any of the walls.
[0020] Referring now to FIGS. 2 , 2 A, and 3 , various views of the interior lining of the cargo container 8 ( FIG. 1 ) are shown. A liner 10 may be configured to resist fire and prevent fire from penetrating through the liner either from within the cargo container 8 or from the exterior of the cargo container 8 . The liner 10 may include a heat resistant sheet of metal 5 positioned between two sheets of copper 6 . The heat resistant sheet of metal 5 may be a metal with a melting point approximately above 1700°. In some embodiments, the liner 10 may be configured to resist or contain a class “D” fire. The heat resistant sheet of metal 5 may be thick enough to prevent fire from penetrating through the heat resistant sheet of metal 5 . The heat resistant sheet of metal 5 may include for example tungsten. In some embodiments, the heat resistant sheet of metal 5 is entirely tungsten. The liner 10 may be disposed against an interior wall of the cargo container 8 . For example, the liner 10 may be positioned over a base 7 . The base 7 may be an aluminum pallet.
[0021] Thus, for example, when combustion occurs within the cargo container 8 , fire may encounter the liner 10 before reaching any of the cargo container 8 walls. Fire may in some cases penetrate through the copper sheet 6 however the sheet of tungsten 5 may then contain the fire. It will be appreciated however, that by covering the sheet of tungsten 5 with copper, the tungsten may be protected from environmental contamination and degradation. For sake of illustration, the liner 10 is shown on the base 7 however it will be understood that the liner 10 may line any interior wall.
[0022] Referring now to FIGS. 4-11 , a fire extinguisher 304 is shown along with an electrical schematic providing detail of electronic connections according to an exemplary embodiment of the present invention. The fire extinguisher 304 may include automatic fire detection and suppression functions.
[0023] The fire extinguisher 304 may include an electronic control box 1 , which may house all electrical circuits and batteries. A fire detector 27 (sometimes referred to as the detector 27 ) may be coupled to the control box 1 . In some embodiments, the detector 27 is a smoke detector or a heat detector. Control and activation of the detector 27 may be controlled by the control box 1 . Detection of a fire by the detector 27 may activate release of a fire extinguishant. An electric actuator 12 may be used to electrically open and close a valve assembly 110 that releases the fire extinguishant housed within a cylinder 2 . A chafe strip 31 may be added to the control box 1 to prevent chafing and keep the control box 1 in place with the cylinder 2 . A personal computer board 15 inside the control box 1 , such as a circuit controller with associated wiring, may be used to mount electrical control devices.
[0024] The cylinder 2 may be a pressure vessel installed to store fire extinguishant under pressure until ready for release. A cylinder mount 28 may be a mounting assembly to hold the pressure cylinder in place. A pressure gauge 106 may indicate amount of pressure inside the cylinder 2 . A valve assembly adapter 107 may be screwed into a valve assembly 110 to allow a spray nozzle 108 to be attached.
[0025] The spray nozzle 108 may be attached to a valve assembly adapter 107 that atomizes the fire extinguishant upon release. A base coupler 109 may attach the actuator base 111 to the pressure cylinder neck adapter. An actuator base 111 may be a mounting bracket for the electric actuator 12 . An actuator coupler 113 may transfer motion from the electric actuator 12 to the valve assembly 110 .
[0026] An attaching hardware 114 , such as a bolt, screw, washer, for example, may be attached to the actuator base 111 . A spray deflector 115 may spread out and help atomize and disperse fluid flowing out of a heat fuse. A threaded pipe elbow 116 may be used for spray nozzle plumbing. A threaded pipe coupler may be used for spray nozzle plumbing.
[0027] A pipe threaded adapter 118 may be included for spray nozzle plumbing. A pressure cylinder neck coupler 120 may be attached to the pressure cylinder neck and the electric actuator base. The pressure cylinder neck adapter 121 may thread into pressure cylinder neck and become an extension of the neck, providing area for heat fuse 122 and the pressure gauge. The heat fuse 122 may be a melting fuse that allows the fire extinguishant to be released under certain atmospheric temperatures.
[0028] A main system battery tray 16 may be used to mount batteries 17 inside the control box 1 . A detector power switch 18 , such as an on/off power switch, may be installed for the detector 27 . A fire suppression power switch 19 , such as an on/off switch, may be used to engage the fire suppression extinguishant release. A reverse polarity switch 20 may have three position switches, for example, to reverse voltage from latching relay to reset system. The detector 27 may sense a fire and may start a relay effect that opens the pressure cylinder 2 while providing an alert to people, such as aircrew via a transmitter 201 . A fire suppression discharge light 29 may alert ground crews that the discharge of the extinguishant has occurred. An actuator reverse switch 30 may allow the actuator 12 to reverse and be placed back into an armed position.
[0029] A voltmeter 21 may be used to monitor system voltage of the detector 27 and electronic control system. A voltage test switch 22 may apply power to the voltmeter 21 for monitoring system voltage. A rubber battery insulation pad 24 may be used to insulate a battery 17 . Strap retention slots 25 may be formed in the control box 1 for holding strap 26 that may retain the pressure cylinder 2 .
[0030] A diode 32 may be placed into electrical circuit to remove AC current. A detector battery 100 may supply main power to detector 27 . A voltage regulator 101 may be installed to provide proper voltage for voltmeter 21 . A fuse 102 may be installed to provide proper voltage for light emitting diode (LED) light. Latching relay 104 may be installed to operate as power relay for the electric actuator, triggered by the detector 27 .
[0031] Some of the electrical components may be mounted on the PC board 15 , which in turn may be mounted in the electronic control box 1 . The detector 27 may be powered by the detector battery 100 , through the detector power switch 18 . The detector 27 may sense the smoke or heat which sends a DC voltage signal to a latching relay 104 through a reverse polarity switch 20 and diode 32 . The reverse polarity switch 20 may be used to reverse the polarity of the battery to reset the latching relay 104 .
[0032] Once the latching relay 104 detects the voltage from the detector 27 , the latching relay 104 may latch and close the circuits from the main system batteries 17 through the fire suppression power switch 19 , the fuse 102 , the fuse holder 105 , and power the electric actuator 12 open. The actuator reverse switch 30 may be installed to switch the electric actuator 12 to a closed position.
[0033] To make sure all circuits are powered properly, a battery test function may be developed. This may consist of a voltmeter 21 , powered by a voltage regulator 101 . The voltage regulator 101 may receive an electrical signal from main system batteries 17 through a voltage test switch 22 and push to test switch 23 to selectively test each battery voltage.
[0034] The main system batteries 17 may be mounted in the control box 1 with two main system battery trays 16 with an attaching hardware 14 . The lower main system battery 17 may be protected from accidental shorting by a rubber battery insulation pad 24 under the upper battery-mounting tray 16 . The electronic control box 1 may be mounted to the pressure cylinder 2 through strap retention slots 25 with control box retaining straps 26 and the chafe strips 31 between the electronic control box 1 and the pressure cylinder 2 .
[0035] A fuse holder 105 may be installed to mount the fuse 102 into the electric circuit. A transmitter power switch 200 may be installed to control the on/off power for a transmitter 201 . The transmitter 201 may be installed to send signal to the receiver 205 to alert the user of possible fire hazard and the extinguishant has been released.
[0036] A transmitter battery 202 may be the main power source for the transmitter 201 . A latching relay 203 may be associated with the transmitter 201 that closes the circuit on the transmitter 201 to send a warning signal, which is triggered by the detector 27 . A push to test switch 210 may allow an operator to test the transmitter 201 without triggering the latching relay 203 .
[0037] A receiver battery 204 may be the main power source for receiver 205 . The receiver 205 may be installed, for example, in a cockpit, to receive a warning signal from the transmitter 201 . The receiver 205 may have a light and buzzer warning for the user alerting the user of an overheat and/or smoke condition existing in the cargo area. The receiver buzzer 206 may alert users to the possibility of a fire hazard.
[0038] The receiver LED 207 may be installed to alert a user to a possible fire hazard. The receiver resistor 208 may be added to the LED circuit to create a proper voltage. A receiver power switch 209 may be installed to control the on/off power for the receiver. A receiver arm or disarm switch 211 may be installed in the LED or buzzer circuit to disarm or shut off the fire hazard warning.
[0039] The transmitter 201 may be powered by the detector battery 202 through the transmitter power switch 200 . When triggered, the latching relay 203 may close and cause the detector input circuit to send signal to the receiver 205 . The receiver 205 may be powered by the receiver battery 204 through the receiver power switch 209 . When triggered, the receiver 205 may produce an electrical current that energizes the receiver buzzer 206 and the receiver LED 207 through the receiver resistor 208 and the receiver arm or disarm switch 211 . The trigger power source for the entire 24 volt mechanical system may be a replaceable 9 volt battery, which may keep this system in a state of low maintenance and high reliability.
[0040] When smoke or heat is introduced to the detector 27 , this may trigger an electrical signal which may be sent to two latching relays. The first latching relay may close a circuit that allows the electric actuator to open the valve assembly 110 and release the fire extinguishant. The second latching relay may close a circuit that allows the transmitter 201 to transmit a signal to the receiver 205 which illuminates a light and sounds a buzzer. If the detector 27 is attached to a computer, the computer may control the electric actuator to release the fire extinguishant and send the signal to the receiver 205 via the transmitter 201 .
[0041] An exemplary embodiment of the present invention may be used to suppress airborne fires, for example, in modified ULDs. Once the ULDs are modified according to an exemplary embodiment of the present invention, a fire extinguisher 304 may be mounted inside the ULD and turned on and armed. The detector 27 and the receiver 205 may be turned on and armed. The early-warning transmitter 201 and receiver 205 may let, for example, a pilot know as soon as a fire erupts and may provide valuable time to get the aircraft on the ground to prevent in-flight catastrophe.
[0042] It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. For example, while the foregoing has been described in the context of protecting cargo, embodiments of the present invention may be placed inside storage rooms to protect property and homes during natural disaster, such as forest fires.
|
A cargo container fire suppression system may prevent fires from spreading within a cargo area into other portions of a craft. A fire resistant liner may be disposed within a cargo container to prevent a fire from penetrating through the liner and burning other elements within the craft beyond the wall(s) of the liner. The suppression system may include a fire sensor and an automatic fire extinguishing device. A transceiver may be coupled to the fire sensor which may remotely alert personnel to a fire occurring in the cargo area.
| 8
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/553,067, filed on Oct. 26, 2006, now U.S. Pat. No. 7,578,308, the entire disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to valves, and more particularly to emergency shutoff valves for use in fuel dispensing systems.
BACKGROUND
Fuel dispensing systems used at retail gas stations typically include an underground tank containing gasoline, diesel fuel or other liquid fuels, an above ground dispensing unit terminating in a nozzle adapted to supply the fuel to a motor vehicle, and a piping system interconnecting the underground tank and dispensing unit. While infrequent, vehicles can collide with the dispensing unit, causing the dispensing unit to be displaced. It is also possible for the unit to be displaced due to certain environmental conditions. In either event, a fuel pipe or conduit may rupture, causing fuel to be spilled and creating a potentially hazardous condition, unless preventive measures are taken.
A variety of emergency fuel shutoff valves are known in the art that have been developed in response to the foregoing potential problem. Known valves of this type include those having upper and lower housings releasably connected to one another, with the lower housing rigidly mounted. For instance, the lower housing can be mounted within a sump located beneath a concrete pedestal supporting the dispensing unit using, for example, a mounting bar as is known in the art. The lower housing is operably connected to the underground tank via underground conduits, while the upper housing is operably connected to the fuel dispensing unit.
A weakened portion, such as a circumferential groove, formed in the upper housing provides a planned failure site so that a first portion of the valve can separate from a second portion of the valve when one of the first or second portions is subjected to a predetermined load. Such a separation of valve portions causes a valve element in the lower housing to move from a releasably latched open position to a closed position, shutting off the flow of fuel from the underground tank. Shutoff valves of this type may also include a check valve in the upper housing that closes under the action of a biasing member when the valve portions separate. The check valve may reduce or prevent the backflow of fuel from the dispensing unit.
Emergency shutoff valves of the foregoing type have been successfully used in fuel dispensing systems, but they can exhibit certain disadvantages. For instance, it is possible for the dispensing unit to be subjected with a load or force that is not sufficient for the first portion of the shutoff valve to be separated from the second portion of the valve, but is sufficient to compromise the structural integrity of the valve housing. In other words, a load may crack the valve housing along the groove without completely separating the valve portions on either side of the groove. In this event, the valve element in the lower housing may not close, which may permit fuel to escape from the housing through the cracked or otherwise damaged weakened portion of the valve, resulting in undesirable spillage of fuel to the environment.
It is therefore desirable to provide an emergency shutoff valve for use in fuel dispensing systems that overcomes the disadvantages associated with known emergency shutoff valves.
SUMMARY
To these ends, an embodiment of the invention contemplates an emergency shutoff valve having a frangible, or weakened portion or other form of predetermined failure area disposed within or forming a portion of an expansible chamber. Any leak from this frangible area, such as might occur from an impact to a fuel dispenser or due to certain environmental conditions, actuates a movable member which defines at least a portion of an expansible chamber, and this movement is operatively coupled to the valve so as to cause it to shut off. Accordingly, fuel leaks from impact or valve trauma less than full valve compromise, i.e., cracking the valve without fully shearing or separating the valve, may be contained or reduced through valve shut off.
More particularly, an emergency shutoff valve according to one embodiment of the invention is provided for use in a fuel dispensing system. The emergency shutoff valve comprises a housing defining a fluid inlet, a fluid outlet and a fluid flow passage extending between the fluid inlet and the fluid outlet. The flow passage may be suitable for the flow of fuel therein. The valve may further include a valve element movable within the housing between an open position, in which fuel is permitted to flow between the fluid inlet and outlet, and a closed position, in which fuel is prevented from flowing between the fluid inlet to the fluid outlet. A latching mechanism may be coupled to the valve element and the housing to releasably latch the valve element in the open position. The valve may also include an expansible member defining at least a portion of a sealed expansible chamber external of the housing. The housing comprises a weakened portion downstream of the valve element and the expansible chamber is sealed to the housing at a first location upstream of the weakened portion and at a second location downstream of the weakened portion so as to bound or enclose the weakened portion. The emergency shutoff valve defines a failure mode wherein the structural integrity of the housing is compromised to an extent wherein fuel may escape from the housing through a crack in the weakened portion and into the expansible chamber when a predetermined load is applied to the housing. Upon occurrence of the failure mode, the expansible member is operable for uncoupling the latching mechanism from at least one of the housing and the valve element, wherein the valve element moves from the open position to the closed position to stop the flow of fuel through the valve. In particular, the pressure in the fuel line causes fuel to flow into the expansion chamber through the crack in the weakened portion of the housing so as to actuate the expansible member thereby causing the valve element to move to the closed position.
In other embodiments, the emergency fuel shutoff valve may include one or more of the following features. In some embodiments, the expansible member may comprise a sleeve, made of an elastomeric material, disposed in surrounding relationship with the housing. The valve further may include a rotatable shaft having one end projecting outwardly from the housing, with the valve element being coupled to the shaft for rotation therewith. A biasing member cooperates with the shaft to bias the valve element toward the closed position.
The latching mechanism may be a linkage. In one embodiment, the linkage includes first and second links, each having proximal and distal ends, with the proximal end of the first link being coupled to the housing and the distal end of the first link being coupled to the proximal end of the second link. The distal end of the second link may be coupled to the end of the rotatable shaft that projects outwardly from the housing. In this embodiment, the expansible member is operable for contacting and moving the first link upon occurrence of the failure mode, wherein the first link is uncoupled from one of the housing and the second link, and wherein the valve element is unlatched and moves from the open position to the closed position. The first link may include a protruding portion disposed between the proximal and distal ends of the first link and protruding toward the expansible member.
Alternatively, the first link may include a first link portion and a second link portion each pivotally coupled to the housing. The first link portion may include a notch and the second link portion may include a first, second and third arm. The proximal end of the second link may include a pin that is received in the notch of the first link portion when the valve element is releasably latched in the open position. The distal end of the second link may be coupled to the end of the rotatable shaft that projects outwardly from the housing. The second arm of the second link portion may extend generally tangentially relative to the housing proximate the expansible member. In this embodiment, the expansible member is operable, upon occurrence of the failure mode, for contacting the second arm, causing the first link to rotate and the pin to become disengaged from the notch in the first link portion, wherein the valve element is unlatched from the open position and moves to the closed position.
In another embodiment, the valve may further comprise an annular member at least partially circumscribing the housing and a hollow protruding member integral with the annular member and extending away from the housing. In this embodiment, the expansible member may comprise a diaphragm made of an elastomeric material and the expansible member can be disposed in sealing engagement with the protruding member. The linkage may comprise first and second links coupled to one another. The first link may be coupled to the housing at its proximal end and coupled to the proximal end of the second link at its distal end. The distal end of the second link may be coupled to the end of the rotatable shaft that projects outwardly from the housing. In this embodiment, the expansible member is operable for contacting and moving the first link upon occurrence of the failure mode wherein the first link is uncoupled from one of the housing and the second link, and the valve element is unlatched and moves from the open position to the closed position.
The weakened portion of the housing may take a variety of forms. In one embodiment, it is a circumferential groove. At least a portion of the groove can be generally V-shaped. The expansible member may be made of any suitable material, including those selected from the group consisting of fluro silicone rubber, BUNA-N rubber, fluro elastomer rubber or other suitable materials.
The housing preferably includes a lower housing and an upper housing secured to one another, with the lower housing adapted to be mounted within a sump beneath a dispensing unit and further adapted to be operatively coupled to a source of pressurized fuel. The upper housing preferably includes the weakened portion and may be adapted to be coupled to a fuel pipe within the dispensing unit. The valve element is preferably disposed within the lower housing, upstream of the weakened or frangible portion of the valve.
The emergency shutoff valve may further include a normally open, second valve element disposed within the upper housing and a biasing member biasing the second valve element toward a closed position.
According to another aspect of the invention, a method is provided for isolating a leak in a fuel dispensing system. The method comprises providing an emergency shutoff valve for use in the fuel dispensing system, with the valve comprising a housing with a weakened portion therein, and the housing defining a fluid inlet, a fluid outlet and a fluid flow passage therebetween. The valve further comprises a valve element movable between an open position and a closed position. The method further comprises providing a linkage coupled to the valve element and the housing, wherein the linkage releasably latches the valve element in the open position. Additionally, the method comprises defining at least a portion of an expansible chamber with an expansible member sealed to the housing at locations upstream and downstream of the weakened portion, wherein the expansible member is operable, upon occurrence of a fuel leak from the fluid flow passage through the weakened portion and into the expansible chamber, for uncoupling the linkage from at least one of the housing and the valve element, wherein the valve element is unlatched and moves from the open position to the closed position to stop the flow of fuel through the valve.
Stated in another way, the method comprises the steps of defining a frangible area in a fluid conduit downstream of a cut-off valve, and disposed within an expansible chamber sealed to the conduit downstream and upstream of the frangible area, and closing the valve upon movement of an expansible member forming at least a portion of the expansible chamber in response to leakage of the fluid through the frangible area. In one aspect of the invention, the pressure in the fuel line is sufficient to actuate the expansible member so as to close the valve when a leak occurs along the weakened or frangible area.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying drawings wherein:
FIG. 1 is a schematic illustration of a fuel dispensing system that incorporates an emergency shutoff valve according to an embodiment of the present invention;
FIG. 2 is a perspective view of the emergency shutoff valve shown schematically in FIG. 1 ;
FIG. 3A is a cross-sectional view taken along line 3 A- 3 A in FIG. 2 , with a valve included in the lower housing shown in an open position;
FIG. 3B is a cross-sectional view similar to FIG. 3A , but with a failure mode associated with a weakened portion of the emergency shutoff valve illustrated;
FIG. 3C is a cross-sectional view similar to FIGS. 3A and 3B , further illustrating the failure mode shown in FIG. 3B ;
FIG. 4 is a cross-sectional view taken along line 4 - 4 in FIG. 2 ;
FIG. 5 is a perspective view of an emergency shutoff valve according to another embodiment of the present invention;
FIG. 6A is a cross-sectional view taken along line 6 A- 6 A in FIG. 5 illustrating the included linkage of the shutoff valve in a position that latches a valve element (not shown in FIG. 6A ) in the lower housing in an open position;
FIG. 6B is a cross-sectional view similar to FIG. 6A , but with the included linkage in a position that unlatches the valve element in the lower housing (not shown in FIG. 6B ), allowing it to move to a closed position;
FIG. 7 is a perspective view of an emergency shutoff valve according to another embodiment of the present invention; and
FIG. 8 is a cross-sectional view taken along line 8 - 8 in FIG. 7 .
DETAILED DESCRIPTION
FIG. 1 is a schematic illustration of a fuel dispensing system 10 that incorporates an emergency shutoff valve 20 according to the present invention. The fuel dispensing system 10 includes a source of fuel 22 having fuel 24 contained therein. As shown in FIG. 1 , the source 22 of fuel may be an underground fuel tank, such as that used at a retail gas station for instance. The fuel dispensing system 10 may further include a stand pipe extending into the fuel tank, a sump 26 , various flow control and flow measurement devices (not shown) and a section of piping 28 that is mechanically and fluidicly coupled to valve 20 . Valve 20 comprises a housing, or fluid conduit, 30 that may include first 32 and second 34 housings that are removably secured to one another by conventional means, such as fasteners 36 shown in FIG. 2 . While the preferred embodiment described herein includes two separate housings 32 , 34 coupled together, the invention is not so limited as the valve 20 may have a one-piece housing. The two-piece structure allows the second housing 34 (which has the shear groove) to be replaced without also replacing the first housing 32 . In the illustrated embodiment, the first housing 32 is a lower housing and the second housing 34 is an upper housing. The terms upper and lower are used to describe embodiments and to facilitate understanding of the invention and does not limit the invention to a certain orientation. Fuel system 10 may further include a fuel dispensing unit 38 that may be mounted on a pedestal 40 , which may be made of concrete and which in turn may be mounted on a surface, such as, for example, a concrete surface of a retail gas station. The lower housing 32 may be rigidly mounted within a sump 41 below or adjacent the pedestal 40 .
The fuel dispensing system 10 may further include a rigid pipe or conduit 42 that may extend upwardly through the interior of the dispensing unit 38 . Pipe 42 may be mechanically coupled, at a lower end, to the upper housing 34 of valve 20 and is in fluid communication with valve 20 . Pipe 42 may also be in fluid communication with a flexible hose 44 that terminates in a nozzle 46 that is adapted for dispensing fuel into the fuel tank of a motor vehicle, such as an automobile, truck, etc.
Referring now to FIGS. 2-4 , housing 30 of valve 20 generally defines a fluid inlet 50 , a fluid outlet 52 and a fluid flow passage 54 extending between the fluid inlet 50 and the fluid outlet 52 . The fluid flow passage 54 may be suitable for the flow of pressurized fuel therein, such as fuel 24 . The fuel 24 may be pressurized by a pump (not shown) included in the fuel dispensing system 10 .
Valve 20 includes a valve member 60 that may be a flapper or butterfly type valve and which may be movably mounted within the lower housing 32 . Valve member 60 includes a valve element 62 that is movable between an open position shown in FIGS. 3A , 3 B and in solid line in FIG. 4 , and a closed position shown in FIG. 3C and in phantom line in FIG. 4 . In the closed position, the valve element 62 , such as a sealing disk, may be disposed in sealing engagement with a valve seat 64 and is adapted to cut off or prevent fuel flow from the fluid inlet 50 to the fluid outlet 52 . The valve element 62 may be supported by a structure, indicated generally at 66 . Additional details of the structure 66 that can be used are found in U.S. Pat. Nos. 5,454,394; 5,193,569; and 5,099,870 that disclose conventional shear valves. Each of these patents is assigned to the assignee of the present invention and is expressly incorporated by reference herein in its entirety. The support structure 66 may include a pair of arms 68 having square openings that are received by a square section of a rotatable shaft 70 , such that the valve element 62 and supporting structure 66 rotate with shaft 70 . Valve element 62 and supporting structure 66 may be biased toward the closed position by a biasing member 72 , which can be a torsion spring, coiled about the shaft 70 . However, the valve element 62 and associated support structure 66 may be releasably latched in the open position by a latching mechanism indicated generally at 74 in FIG. 2 . In the illustrated embodiment, latching mechanism 74 may be a linkage. However, latching mechanism 74 may be other devices suitable for releasably latching valve element 62 in the open position. During normal operation of valve 20 , i.e., not during a failure mode of valve 20 , the linkage 74 may be coupled to both the valve element 62 and to housing 30 as explained in more detail below.
Linkage 74 may include a first link 76 having a proximal end 78 coupled to housing 30 . In the illustrated embodiment, this is accomplished by a pin 80 secured at one end to housing 30 and having an opposite end extending through an aperture formed in the proximal end 78 of first link 76 . First link 76 further includes a distal end 82 that is coupled to a proximal end 84 of a second link 86 of linkage 74 . A distal end 88 of second link 86 may be coupled to an end 90 ( FIG. 3A ) of the rotatable shaft 70 that projects outwardly from the housing 30 . First link 76 may also include a protruding portion 92 that is disposed between the proximal 78 and distal 82 ends of first link 76 and is used for a subsequently discussed purpose.
The outer end 90 of the rotatable shaft 70 may include a cylindrical portion and the distal end 88 of second link 86 may include a circular aperture formed therein that engages the cylindrical portion of the outer end 90 of shaft 70 . The distal end 88 of second link 86 may be secured to the outer end 90 of shaft 70 by soldering for instance, with the solder having a relatively low melting point. Accordingly, in the event of a fire surrounding valve 20 , the solder can melt, allowing shaft 70 to rotate within second link 86 , thereby causing the valve element 62 and supporting structure 66 to move from the open position shown in FIGS. 3A and 3B and in solid line in FIG. 4 , to the closed position shown in FIG. 3C and in phantom line in FIG. 4 , under the action of the biasing member 72 . Alternatively, and in accordance with another embodiment of the invention, instead of the distal end 88 of the second link 86 being configured as a fusible hub that releases the valve element 62 in the event of a fire, as is conventional, the first link 76 may include a fusible section intermediate the proximal and distal ends 78 , 82 . Thus, in the event of a fire, the fusible section melts separating the end 78 , 82 of the first link 76 and allowing the valve element 62 and supporting structure 66 to move to the closed position under the action of biasing member 72 . Implementing the fusible section in the first link 76 may provide certain cost and manufacturing advantages as compared to the traditional placement of a fusible section in the distal end 88 of the second link 86 .
Housing 30 includes a weakened, or frangible, portion 94 formed therein that is downstream of valve member 60 . In the illustrated embodiment, upper housing 34 includes the weakened portion 94 formed therein, which extends circumferentially around a perimeter of the upper housing 34 . The invention, however, is not so limited. The weakened portion 94 may be a groove and can have an inner portion 96 that is generally V-shaped, as shown in the illustrated embodiment. The invention is not so limited as those of ordinary skill in the art will recognize other configurations that define the weakened portion 94 . The weakened portion 94 defines a predetermined fracture of failure site for various failure modes as subsequently discussed.
In an exemplary embodiment, valve 20 may further include an expansible member 100 . The expansible member 100 may be a sleeve disposed in surrounding relationship with the weakened portion 94 , as shown in the illustrated embodiment, and member 100 may be made of an elastomeric material. Suitable materials include fluro silicone rubber, BUNA-N rubber and fluro elastomer rubber. However, other materials may be used provided they exhibit sufficient resistance to ozone, to prevent dry rot, and are resistant to fuel corrosion. The expansible member 100 generally surrounds the weakened portion 94 and may be sealed to the upper housing 34 at a first location 102 upstream of the weakened portion 94 and at a second location 104 downstream of the weakened portion 94 so as to bound or encompass weakened portion 94 . The expansible member 100 may be sealed to the upper housing 34 by a pair of band clamps 106 that extend around the perimeter of upper housing 34 or other suitable devices such as straps and the like. The expansible member 100 defines at least in part an expansible chamber 108 best seen in FIGS. 3B and 3C . The function of the expansible member 100 is subsequently discussed.
Valve 20 may optionally include a second valve member 110 disposed within the upper housing 34 of valve 20 , downstream of the weakened portion 94 . Valve member 110 may, for example, be a spring loaded poppet or check valve having a valve element 112 that may be a sealing disk. Valve member 110 may be normally open and held in the open position during operation of valve 20 by an abutment structure indicated generally at 114 that is secured to the upper housing 34 . Other details of valve member 110 and the configurations of abutment structures 114 that may be used are more fully discussed in U.S. Pat. Nos. 5,454,394; 5,193,569; and 5,099,870 referenced previously, which disclose similar poppet valve and abutment structures. Alternatively, valve member 110 may be held in an open position during normal operation of valve 20 by the pressure of the fuel flowing within valve 20 . Valve member 110 may be biased toward a closed position by a biasing member 116 that may, for example, be a coil spring. In the closed position, the valve element 112 is disposed in sealing engagement with a valve seat 118 formed in the upper housing 34 . Valve member 110 may be forced closed by biasing member 116 in the event of certain failure modes, as subsequently discussed. Valve 20 may also optionally include a pressure relief valve (not shown) that can be disposed in a tubular stem 120 of valve member 110 . The features of relief valves that may be used are discussed in the previously referenced patents. In any event, the pressure relief feature prevents a large pressure build up in the piping above the valve 20 on the occasion that the valve is sheared or separated.
Since the lower housing 32 of valve 20 is rigidly mounted within sump 41 , when a predetermined load or force 122 is exerted on the housing 30 of valve 20 (shown as acting on upper housing 34 , but load 122 could also act on lower housing 32 ) on either side of the weakened portion 94 , either directly or indirectly, valve 20 can define a failure mode that depends on the value of force 122 . The most common instance that may create a failure in the housing 30 is the inadvertent contact of a motor vehicle with the fuel dispensing unit 38 that houses pipe 42 . However, a failure in housing 30 may result from any relative movement between portions of the housing 30 above and below weakened portion 94 caused by external forces including frost heave and other environmental conditions. In one failure mode, the force 122 is not sufficient to cause a first portion 124 of the housing 30 to substantially completely separate from a second remainder portion 125 of housing 30 along weakened portion 94 (valve shearing), but is sufficient to cause a crack 126 or other distress in housing 30 , indicated in exaggerated form in FIGS. 3B and 3C , to emanate from the weakened portion 94 whereby the fluid flow passage 54 is in fluid communication with the expansible chamber 108 (valve cracking). Accordingly, in this failure mode, the structural integrity of housing 30 is compromised to an extent wherein the fuel flowing within passage 54 can escape from housing 30 through the weakened portion 94 and into the expansible chamber 108 under the fuel line pressure. This in turn causes the expansible member 100 to expand outwardly as shown in FIGS. 3B and 3C , as a result of the pressurized fuel entering chamber 108 . Since the expansible member 100 is sealed to the upper housing 34 , any fuel entering chamber 108 is retained therein, which prevents or reduces fuel from escaping from the valve 20 and thereby reduces the likelihood of environmental spills and the costs associated with the cleanup of such spills.
The protruding portion 92 of first link 76 may be disposed in relatively close proximity to the expansible member 100 . Accordingly, when the member 100 expands outwardly, due to pressurized fuel entering expansible chamber 108 , it contacts the protruding portion 92 of first link 76 so that first link 76 uncouples from at least one of the housing 30 and the second link 86 . In the illustrated embodiment, the proximal end 78 of first link 76 disengages from the pin 80 secured to housing 30 as shown in FIGS. 3B and 3C so that first link 76 uncouples from housing 30 . In other embodiments, first link 76 may be uncoupled from second link 86 or from both housing 30 and second link 86 . When first link 76 is uncoupled from one or both of the housing 30 and second link 86 , valve element 62 is unlatched from the open position and moves to the closed position as shown in solid line in FIG. 3C and in phantom line in FIG. 4 due to the action of biasing member 72 . When valve element 62 is in the closed position, fuel is prevented from flowing from the fluid inlet 50 to the fluid outlet 52 . Instead, fuel entering inlet 50 after valve element 62 is closed is retained within lower housing 32 , thereby avoiding or reducing the likelihood of fuel spillage externally of housing 30 .
When force 122 has a relatively higher value, the weakened portion 94 may define another failure mode (not shown herein) wherein the first portion 124 of housing 30 separates substantially completely from the second portion 125 of housing 30 . In this valve shearing failure mode, the expansible member 100 does not prevent or otherwise inhibit such separation of the first portion 124 of housing 30 from the second portion 125 of the housing 30 . Instead, the force 122 may cause the expansible member 100 to disengage from the housing 30 in a manner that permits the separation of the first and second portions 124 , 125 . The separation of the valve housings that do not include the expansible member in accordance with the invention, such as member 100 , but are otherwise similar to valve 20 , are illustrated in the foregoing referenced patents. In the event of this valve shearing failure mode, first link 76 would also be uncoupled from one or both of the housing 30 and second link 86 , such that valve element 62 would move to the closed position under the action of biasing member 72 and the valve element 112 of the poppet or check valve 110 would also move to the closed position under the action of biasing member 116 . Accordingly, when the valve element 42 moves to the closed position, fuel may be prevented from flowing through the lower housing 32 and externally of valve 20 . Also, any fuel contained within the pipe 42 may be prevented from backflowing through the upper housing 34 and externally of valve 20 . Accordingly, the likelihood of fuel spillage externally of valve 20 would be prevented or reduced.
FIGS. 5 , 6 A and 6 B, in which like reference numerals refer to like features in FIGS. 1-4 , illustrate a valve 130 according to another embodiment of the invention. Valve 130 includes a housing, or conduit, 132 comprising an upper housing 134 and a lower housing 32 . Upper housing 134 may be removably secured to lower housing 32 by conventional means such as fasteners 136 . Again, while this embodiment is shown and described as a two-part housing, the invention is not so limited as a one-piece housing may also be utilized. Housing 132 defines a fluid inlet 138 , a fluid outlet 140 and a fluid flow passage 142 ( FIGS. 6A and 6B ) extending between the fluid inlet 138 and the fluid outlet 140 . The fluid flow passage 142 may be suitable for the flow of pressurized fuel therein, such as fuel 24 .
Valve 130 may further include an expansible member 144 , in lieu of expansible member 100 , that defines an expansible chamber 145 ( FIG. 6B ) and is disposed in surrounding relationship with a weakened, or frangible, portion 146 formed in upper housing 134 and is sealed to the upper housing 134 at a first location 148 downstream of the weakened portion 146 and at a second location 149 upstream of the weakened portion 146 . The weakened portion 146 may be a groove extending around a perimeter of upper housing 134 and may be generally V-shaped as shown in FIGS. 6A and 6B . The expansible member 144 may be a sleeve and may have a somewhat different configuration than the expansible member 100 , as shown in FIGS. 6A and 6B . Expansible member 144 may be made of the same elastomeric materials discussed previously with regard to expansible member 100 .
Valve 130 may include a latching mechanism, indicated generally at 149 , which releasably latches the valve element 62 , disposed in the lower housing 32 , in the open position. In the illustrated embodiment, latching mechanism 149 may be a linkage. However, latching mechanism 149 may be other devices suitable for latching valve element 62 in the open position. During normal operation of valve 130 , i.e., not during a failure mode of valve 130 , linkage 149 may be coupled to both valve element 62 and housing 132 . Linkage 149 may include a first link 150 having a first link portion 152 that is pivotally coupled to housing 132 . The pivotal coupling of first link portion 152 to housing 132 may be achieved by a pin 154 , or like member, which extends through first link portion 152 into an embossment 156 secured to upper housing 134 . The first link 150 may further include a second link portion 158 also pivotally coupled to housing 132 . In the illustrated embodiment, pin 154 passes through both of the first and second link portions 152 , 158 and into embossment 156 . Second link portion 158 includes a first arm 160 pivotally coupled to pin 154 , a second arm 162 coupled to the first arm 160 , and a third arm 164 that is coupled to second arm 162 and also pivotally coupled to the upper housing 132 . Second arm 162 extends generally tangentially relative to upper housing 134 of housing 132 proximate the expansible member 144 . The pivotal coupling of third arm 164 to housing 132 may be achieved by a pin 166 , or like member, which extends through third arm 164 into an embossment 168 secured to upper housing 134 . Pins 154 and 166 may be coaxially disposed so that first and second link portions 152 and 158 pivot together about a centerline axis 170 of pins 154 and 166 , which may be separate pins or can be made as a one piece construction. Moreover, while second link portion 158 is shown and described as an integral member, i.e., the first, second and third arms 160 , 162 , and 164 are integrally formed, those of ordinary skill in the art will recognize that the arms may be separate and then assembled to form second link portion 158 .
As best seen in FIGS. 6A and 6B , first link portion 152 may include a notch 180 formed therein. Linkage 149 further includes the second link 86 as in valve 20 and discussed previously. Second link 86 may also include a pin 182 extending from second link 86 that is received in the notch 180 of first link portion 152 . A biasing member 184 , which may be a spring coiled about pin 154 , biases the first link portion 152 toward a position wherein pin 182 is engaged in notch 180 . For instance, in FIGS. 6A and 6B , the spring biases first link portion 152 in the counterclockwise position. In this position, valve element 62 of valve 60 , disposed in lower housing 32 and illustrated and discussed previously with regard to valve 20 (not shown in FIGS. 5-6B ), is latched in an open position.
Since the lower housing 32 of valve 130 is rigidly mounted within sump 41 , when a predetermined force 190 is exerted on the housing 132 of valve 130 (shown as acting on upper housing 134 , but load 190 could also act on lower housing 32 ) on either side of the weakened portion 146 either directly or indirectly, valve 130 can define a failure mode that depends on the value of force 190 . The most common instance that may create a failure in housing 132 is the inadvertent contact of a motor vehicle with the fuel dispensing unit 38 that houses pipe 42 . However, a failure in housing 132 may result from any relative movement between portions of the housing 132 above and below weakened portion 146 caused by external forces such as frost heave or other environmental conditions. In one failure mode, the force 190 is not sufficient to cause the first portion 124 of housing 132 to substantially completely separate from the second remainder portion 125 of the housing 132 along weakened portion 146 (valve shearing), but is sufficient to cause a crack 194 or other distress, indicated in exaggerated form in FIG. 6B , to emanate from the weakened portion 146 whereby the fluid flow passage 142 is in fluid communication with the expansible chamber 145 (valve cracking). Accordingly, in this failure mode, the structural integrity of housing 30 is compromised to an extent wherein the fuel flowing within passage 142 can escape from housing 132 through the weakened portion 146 and into the expansible chamber 145 under fuel line pressure. This in turn causes the expansible member 144 to expand outwardly as shown in FIG. 6B , as a result of the pressurized fuel entering chamber 145 . Since the expansible member 144 is sealed with the upper housing 134 , any fuel entering chamber 145 may be retained therein, which may prevent or reduce the likelihood of fuel spillage externally of valve 130 .
The second arm 162 of second link portion 158 is disposed in relatively close proximity to the expansible member 144 . Accordingly, when the expansible member 144 expands outwardly, due to pressurized fuel entering expansible chamber 145 , it contacts second arm 162 so that second link portion 158 rotates upwardly relative to the upper housing 134 and about axis 170 . Due to the connection at pin 154 , first link portion 152 rotates downwardly relative to upper housing 134 about axis 170 , thereby disengaging pin 182 from notch 180 . This rotation of first link portion 152 uncouples the first link portion 152 from second link 86 , which is coupled to valve element 62 (shown and discussed previously with regard to valve 20 ; not shown in FIGS. 5 , 6 A and 6 B). Accordingly, valve element 62 is unlatched from the open position and moves to a closed position (shown previously with respect to valve 20 ) within the lower housing 32 due to the action of biasing member 72 . When valve element 62 is in the closed position, fuel is prevented from flowing from the fluid inlet 138 to the fluid outlet 140 . Instead, fuel entering inlet 138 after valve element 62 is closed is retained within lower housing 32 . Accordingly, the likelihood of fuel spillage externally of valve 130 may be reduced or prevented.
In the illustrated embodiment, valve 130 does not include the poppet or check valve 110 . However, this may be optionally included in other embodiments. If poppet valve 110 is included, the poppet valve 110 may be moved to a closed position, as discussed previously with regard to valve 20 when a relatively larger predetermined load causes the housing 132 to substantially completely separate. The expansible member 144 does not prevent or otherwise inhibit this separation of the housing 132 . Linkage 149 is also uncoupled from valve element 66 in this valve shearing failure mode, so that valve element 62 moves to the closed position under the action of biasing member 72 . The poppet valve may also move to the closed position as discussed previously with respect to valve 20 , if incorporated in valve 130 .
FIGS. 7 and 8 , in which like reference numerals refer to like features in FIGS. 1-6 , illustrate an emergency shutoff valve 200 according to another embodiment of the invention. Valve 200 comprises a housing 210 that includes the lower housing 32 as described for valves 20 and 130 and discussed previously, and an upper housing 212 that may be removably secured to the lower housing 32 by conventional means, such as bolts 214 . The Housing 210 may be a one-piece construction instead of the two-part construction described herein. Housing 210 of valve 200 defines a fluid inlet 220 , a fluid outlet 222 and a fluid flow passage 224 extending between the fluid inlet 220 and the fluid outlet 222 as shown in FIG. 8 . Fluid flow passage 224 may be suitable for the flow of pressurized fuel therein, such as fuel 24 .
As with valves 20 and 130 , the shutoff valve 200 includes a valve member 60 that can be a flapper or butterfly type valve that is movably mounted within the lower housing 32 . Valve member 60 includes the valve element 62 that is movable between an open position and a closed position as illustrated and discussed previously with respect to valve 20 . Valve element 62 may be biased toward a closed position by the biasing element 72 as discussed previously with respect to valve 20 . When valve element 62 is in the closed position, fuel flow between fluid inlet 220 and fluid outlet 222 is prevented.
Shutoff valve 200 may include a latching mechanism indicated generally at 229 in FIG. 7 , which releasably latches valve element 62 in the open position. In the illustrated embodiment, latching mechanism 229 may be a linkage. However, latching mechanism 230 may be other devices suitable for latching valve element 62 in the open position. During normal operation of valve 200 , i.e., not during a failure mode of valve 200 , linkage 229 may be coupled to both the valve element 62 and to housing 210 . Linkage 229 may include a first link 230 and may also include the second link 86 , as in valves 20 , 130 and discussed previously, which is coupled to valve element 62 in the same manner as discussed previously with respect to valve 20 . First link 230 includes a proximal end coupled to housing 210 . This can be accomplished by a pin 236 that passes through a proximal end of link 230 into an embossment 238 secured to the upper housing 212 of valve 200 as shown in the illustrated embodiment. A distal end of first link 230 may be coupled to second link 86 . This may be accomplished by a pin 240 extending from the proximal end 84 of second link 85 that passes through the distal end of first link 230 as shown in the illustrated embodiment. The first link 230 latches the valve element 62 in an open position when the linkage 229 is coupled to both housing 210 and valve element 66 .
Housing 210 may include a weakened, or frangible, portion 242 formed therein that is downstream of the valve element 62 . In the illustrated embodiment, upper housing 212 may include the weakened portion 242 formed therein, which extends circumferentially around a perimeter of the upper housing 212 . The invention, however, is not so limited. The weakened portion 242 may be a groove and may have an inner portion that is generally V-shaped, as shown in FIG. 8 . The weakened portion 242 defines a predetermined fracture or failure site for various failure modes as subsequently discussed.
Valve 200 may further include an annular member 246 that partially circumscribes the upper housing 212 and may be sealed to the upper housing 212 at locations that are upstream and downstream of the weakened portion 242 , which may be accomplished using O-rings 248 , for example. Annular member 246 may be made of a variety of materials including plastics, metals and elastomeric materials. A hollow protruding member 250 may be formed integral with the annular member 246 and extends away from the upper housing 212 . Valve 200 may further include an expansible member 252 that comprises a diaphragm in the illustrated embodiment that is disposed in sealing engagement with the protruding member 250 . An upper portion 253 of first link 230 is disposed proximate the hollow protruding member 250 . Expansible member 252 may be made of an elastomeric material such as the materials discussed previously with regard to the expansible member 100 of valve 20 . The expansible member may also be inelastic but be formable so as to operate as a rolling diaphragm. Expansible member 252 defines at least a portion of an expansible chamber 254 that is disposed externally of housing 210 , and more particularly is disposed externally of the upper housing 212 . The expansible chamber 254 includes at least the space within the hollow protruding member 250 between the expansible member 252 and the upper housing 212 . Depending upon the properties of the material used to make the annular member 246 , the expansible chamber 254 may also include the space between the annular member 246 and the upper housing 212 , including the space between the weakened portion 242 and annular member 246 .
Since the lower housing 32 of valve 200 is rigidly mounted with sump 41 , when a predetermined force 270 is exerted on the housing 210 of valve 200 on either side of the weakened portion 242 , either directly or indirectly, valve 200 may define a failure mode that depends on the value of force 270 . In one failure mode, the force 270 is not sufficient to cause a first portion 124 of housing 210 to substantially completely separate from a second remainder portion 125 of housing 210 along weakened portion 242 (valve shearing), but is sufficient to cause a crack 274 or other distress emanating from the weakened portion 242 , indicated in exaggerated form in FIG. 8 . In this failure mode, the fluid flow passage 224 is in fluid communication with the expansible chamber 254 . Accordingly, in this failure mode, the structural integrity of housing 210 is compromised to an extent wherein the fuel flowing within passage 224 can escape from housing 210 through the weakened portion 242 and into the expansible chamber 254 under fuel line pressure. This in turn causes the expansible member 252 to expand outwardly as shown in phantom line in FIG. 8 , as a result of the pressurized fuel entering chamber 254 . Since the expansible member 252 is sealed to the upper housing 212 , fuel entering chamber 254 is retained therein, which may prevent or reduce fuel from escaping from the upper housing 212 externally of valve 200 .
The first link 230 of linkage 229 is disposed in relatively close proximity to the expansible member 252 . Accordingly, when the expansible member 252 expands outwardly under fluid pressure it contacts first link 230 so that first link 230 moves outwardly as shown in phantom line in FIG. 8 and is uncoupled from housing 210 and second link 86 . In other embodiments, it is possible for first link 230 to become uncoupled from only one of the housing 210 and second link 86 . When first link 230 is uncoupled from one or both of the housing 210 and second link 86 , valve element 62 may be unlatched from the open position and moves to the closed position, as discussed and illustrated previously with respect to valve 20 . When valve element 62 is in the closed position, fuel is prevented from flowing from the fluid inlet 220 to the fluid outlet 222 . Instead, fuel entering inlet 220 after valve element 62 is closed may be retained within lower housing 32 , thereby preventing or reducing the likelihood of spillage of fuel externally of housing 210 .
In the illustrated embodiment, valve 200 does not include the poppet or check valve 110 shown and discussed previously with regard to valve 20 . However, valve 110 may be optionally included in other embodiments. If poppet valve 110 is included, the poppet valve 110 may be moved to a closed position, as discussed previously with regard to valve 20 when the load 270 has a relatively larger value, than that existing in the first failure mode, causing the first portion 124 of housing 210 to substantially completely separate from the second portion 125 of housing 210 . The annular member 246 , protruding member 250 and expansible member 252 do not significantly prevent such separation of the housing 210 , i.e., they are not made of materials that would prevent such separation. In this event, the poppet valve 110 would move to the closed position as discussed previously, preventing or reducing the backflow of fuel from the dispensing unit through valve 110 , thereby preventing or reducing the likelihood of spillage external of valve 200 . Additionally, the first link 230 would be uncoupled from one or both of housing 210 and second link 86 in this valve shearing failure mode as well, so that valve element 62 would move to the closed position and stop the flow of fuel through valve 200 .
The various embodiments of the emergency shutoff valve as disclosed herein generally have a housing with a weakened portion and an expansible member defining at least a portion of an expansible chamber in surrounding relationship to the weakened portion. The expansible member may be operatively coupled to a valve member in the shutoff valve to close the flow of fuel through the valve when the expansible member is actuated. The valves disclosed herein provide certain advantages over existing shear valves. In particular, for failure modes that crack the valve without substantially completely shearing the valve, the valve according to embodiments of the invention prevent or reduce the likelihood of fuel spillage that would otherwise occur with existing shutoff valves. In addition, this benefit is attained by using the fuel line pressure itself as the motive force for closing off the valve in such a valve cracking failure mode. Thus, no additional energy or energy consuming components must be supplied to the shutoff valve to actuate the valve to a closed position. The shutoff valves according to the invention then provide additional benefits relative to conventional valves in a low cost manner that utilizes the pressure of the fueling system to achieve these benefits.
While the foregoing description has set forth various embodiments of the present invention in particular detail, it must be understood that numerous modifications, substitutions and changes can be undertaken without departing from the true spirit and scope of the present invention as defined by the ensuing claims. The invention is therefore not limited to specific embodiments as described, but is only limited as defined by the following claims.
|
An emergency shutoff valve includes a fluid conduit having a frangible area defined therein, a valve member operatively coupled to said conduit upstream of the frangible area, an expansible chamber having the frangible area defined therein, a movable member defining at least a portion of the expansible chamber, and a linkage operatively coupled to the movable member and the valve member for shutting the valve upon movement of the movable member in response to leakage of fluid through the frangible area. A method of shutting off fuel includes defining an expansible chamber about a frangible area in the conduit, moving a member defining a portion of the expansible chamber in response to leaking fuel, and shutting off a fuel valve in response to moving the movable member.
| 5
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an energy-saving solar air conditioning system for buildings. Particularly, the present invention relates to an energy-saving air conditioning system by which, in winter, the preheated air will be introduced into buildings; and in summer, the hot indoor air will be expelled out of the buildings and fresh air will be guided into the buildings.
2. Description of the Related Art
With increasing CO 2 emissions, the global climate has become abnormal and ecological destruction has increased greatly. As a result, industrialized countries have again become aware of the urgency to reduce their dependence on fossil fuels after the energy crisis in the 70's. Consequently, these countries have given positive comments on how to use solar energy more effectively. Though the technology field still has reservations about whether solar energy will be able to replace other energy resources in the near future, one thing that is almost certain is that solar energy will be playing a very important role in a number of fields, especially those related to domestic heating and air ventilation.
As far as an air conditioning system using solar energy for domestic heating and air ventilation is concerned, a solar collector is the key device for the system, and it has to be mounted at an outdoor location where sufficient sunlight can be collected, such as on a roof or wall. In the past, a lot of effort has been made in developing solar collectors with different functions and styles. Many of them have been disclosed in patent literature. The most typical example is glazing a glass panel or transparent panel onto a fixed outer frame of a heat-insulated chamber and passing fluid through black heat-absorbing plates or pipes installed inside the chamber, so as to absorb the solar energy. Examples include the solar hot water supply system disclosed in U.S. Pat. No. 4,418,685, the air ventilation facility disclosed in WO9,625,632, the roof-style air ventilation facility disclosed in US2002/0,032,000A1, and the wall-style air preheater disclosed in U.S. Pat. No. 4,934,338. However, the solar collectors used presently still have some drawbacks. Therefore, there is much room for improvements in applying and promoting the usage of solar energy to save energy and facilitate air conditioning in buildings. The aforementioned drawbacks include:
(1) The conventional solar collector is too heavy. Its long-term use may cause a load to some buildings.
(2) The structure of the conventional solar collector is complicated, which makes its installation and maintenance difficult. Moreover, it increases the costs and thus prolongs the return period.
(3) The conventional solar heating device has poor compatibility and flexibility to match every type of buildings. Very often, it has to be custom-made.
(4) The contour of the solar collector is obtrusive and often impairs the aesthete and harmony of the overall appearance of the buildings.
(5) The package of the collector takes up much space and increases the costs for storage, commodity display, and channel marketing.
(6) The integral assembly of the whole-unit product is bulky, making it difficult for the application on a large area and increases installation cost.
(7) Glass or transparent panels are glazed onto the outer frame of a heat-insulated chamber. Different thermal expansion coefficients of materials may cause thermal stress problems.
(8) The conventional design cannot satisfy clients' senses of participation and achievement by self-installing the collectors.
(9) Some of the conventional designs can only be applicable to the buildings which are under construction and well-planned for its installation. For most existing buildings, the designs are unsuitable.
(10) When air passes over a glazed panel, heat is dissipated unless a double-glazing is used, but it is expensive and troublesome.
(11) Hot water supply systems or liquid systems operated by solar heating have the problems due to potential of freezing and leakage which impede to reach the expected performance.
BRIEF SUMMARY OF THE INVENTION
To overcome the above drawbacks, the present invention provides a simple, inexpensive, compact and elegant air conditioning system which has a high efficiency of heat-absorption and is a modular arrangement. This system is directed to a passive energy-saving air conditioning system which is driven by solar energy and thus is environmental friendly. The present invention can flexibly provide different numbers of heat-absorbing units according to the air conditioning capacity of different buildings, such that, in summer time, the used air can be expelled outdoors and fresh air can be introduced indoors; and in winter time, the pre-heated air can be provided indoors so as to create a better indoor air quality. Moreover, since the present system is a highly reliable modular design, it provides the ease of displaying and convenience of delivering via marketing channels. In addition, the simple structure and the lightweight components of the present invention allow users to assemble and install the system by themselves as DIY has become a trend for home appliances.
The present invention provides buildings with a novel modular air conditioning system that utilizes solar power for heating air. Such a system is connected to indoor exhaust pipes, indoor inlet pipes, and the paths that communicate to the outdoors. The system mainly contains a solar collector assembly, an inlet assembly and an outlet assembly, which are respectively described in details as follows:
(1) Solar Collector Assembly
A solar collector assembly, used as an air heating path, is comprised of a heat-absorbing set, a transparent top panel, and a fixed support base. The heat-absorbing set is made of a plurality of modular heat-absorbing units. A configuration of the unit can be a fixed component that consists of two pieces of support boards and a piece of heat-absorbing plate. By forming an elongated groove on either both ends or the same end of the two support boards, the support boards can engage with the corresponding positioning grooves formed on the heat-absorbing plate. Then, the heat-absorbing unit with two support boards and a heat-absorbing plate is established. The heat-absorbing plate can use aluminum material which has received an anodic treatment such that the surface thereof is black. As to the top and bottom support boards, the material used therefor can be of the same material as the heat-absorbing plate or other materials.
The present invention positions several adjoining modular heat-absorbing units on a roof to form a heat-absorbing set with a plurality of heating channels. The black heat-absorbing set can greatly enhance the absorption rate of solar radiation. The increase in temperature of the heat-absorbing set directly improves the efficiency in heating air. In addition, this solar collector assembly can be installed horizontally or obliquely, or vertically attached to walls. Compared with the conventional solar collector, the modular heat-absorbing unit in accordance with the present invention can save packaging costs and the space required for storage and display. Moreover, the present invention can be distributed easily through marketing channels and assembled on site. Further, the arrangement of the modular heat-absorbing units can be adjusted and installed to meet the needs of different users. The present invention has a simple structure and light-weight, making it highly compatible to different styles of roofs. In addition, it can be used on large areas to collect solar energy. Finally, lower price and thinner overall appearance of the present invention permits great aesthetic improvements.
The transparent panel is disposed above the heat-absorbing set. Such a panel is used to enhance the green house effect of the solar collector assembly and then facilitate the collection of solar radiation and the heating-up of the heat-absorbing units. Air can be heated when it passes through the heating channels formed in the heat-absorbing set. The present invention can be better used on large areas to collect solar energy. Since it requires no conventional heat-insulated chamber with a fixed outer frame, there is no need to glaze the transparent panel on the top of the conventional heat-insulated chamber. The transparent panel used in the present invention is mounted on the top of the support boards of the heat-absorbing set and is secured to a support base of the solar collector assembly by screws. This transparent panel can be in the form of a corrugated plate or a flat plate. In addition to glass, the material of the panel can be glass fiber, plastics or other commercially available weatherproof transparent materials that can be easily acquired and size-adjusted. The absence of glazing the transparent panel onto the conventional heat-insulated chamber with a fixed outer frame prevents the panel from deformation or damage problems related to thermal stress caused by the difference in thermal expansion coefficients between them.
The support base of the solar collector assembly can be a roof or fixed boards installed additionally on the roof or wall for securing and supporting the solar collector assembly and serving as the base thereof. Beneath the heat-absorbing set, a heat-insulated layer can be added to protect the roof from over-heating. This allows air flow through the multiple lower heat-absorbing channels formed between the heat-absorbing plates and the heat-insulated layer above the support base, and through the multiple upper heat-absorbing channels formed between the heat-absorbing plates and the transparent panel to be heated up with the increase of heating efficiency.
Besides closing the entrances and exits of the multiple upper heat-absorbing channels, the adjustment of the height ratio of the support boards above and below the heat-absorbing plates, which allows more air to go through the lower heat-absorbing channels to be heated up, can also prevent the loss of heat through the transparent panel. Therefore, although the present invention has only one transparent panel, because most of the air flows through the lower heat-absorbing channels, the system demonstrates the same heat insulation effect as that of a double-glazing system. This improves the heating efficiency. When the temperature of air passing through these heat-absorbing channels becomes higher, the density of the air becomes lower than the indoor air density, which causes stronger thermal buoyancy. The resulting thermal buoyancy will lead hot indoor air to flow up and be expelled. Consequently, a comfortable living environment with better indoor air circulation will be created.
(2) Inlet and Outlet Assemblies
The inlet assembly connects to the indoor exhaust pipes and the paths communicating to the outdoors. The outlet assembly connects to indoor inlet pipes and the paths communicating to the outdoors. The sizes of the cross section of the paths are determined by the size of the solar collector assembly. Both inlet and outlet assemblies have structures that communicate to all heat-absorbing channels in the solar collector assembly, and have at least one modular ventilation damper assembly for opening and closing the paths communicating to the outdoors. The ventilation damper assemblies are mounted to the inlet and outlet assemblies by fixing the flanges thereof to the pre-set openings formed on the inlet and outlet assemblies. The difference between the inlet assembly and the outlet assembly lies in the directions of the openings thereof, wherein the pre-set openings formed on the inlet assembly are located oppositely to the heat-absorbing channels, whereas the pre-set openings formed on the outlet assembly face upwards. In order to prevent rain from getting into the ventilation damper assemblies mounted on the upward openings of the outlet assembly, a transparent canopy can be added above the outlet assembly.
In addition, toward the direction of the heat-absorbing channels, both the inlet and outlet assemblies have a blank side for connecting to the transparent panel of two ends of the solar collector assembly. Once the panel connects with the sides, the connections should be sealed. As to the inlet and outlet assemblies, they are fixed to the roof or other fixed boards. An air distributor is respectively located at the joints where the inlet assembly connects to the indoor exhaust pipes and the joints where the outlet assembly connects to the indoor inlet pipes. On such distributors, drilled holes are arranged uniformly on the side facing the heat-absorbing channels. The function of these holes is to evenly distribute air flow into each heat-absorbing channel in order to increase the overall heat-absorbing efficiency of the entire system. By switching and adjusting the openings of indoor pipes and the paths communicating to the outdoors, the heated air can be fanned indoors for heating purposes during wintertime or in cold weather, while during summertime or in hot weather, the air that goes to the indoor exhaust pipes can be heated and expelled outdoors due to the chimney effect caused by thermal buoyancy and the outdoor air from cold locations can be further introduced into the buildings to achieve the effect of air conditioning with cooled air circulation.
The aforementioned simple and reliable modular ventilation damper assemblies are located on the pre-set openings of the inlet assembly and the outlet assembly. By opening or closing the ventilation damper assemblies, the system can communicate to or be isolated from the outdoor environment. The basic structure of the ventilation damper assembly has multiple blades which are supported on both sides of an outer frame by means of parallel pivots. Each pivot is positioned on a shaft bearing clamped on the outer frame and a fastener is used to lock the bearing. Thus, when being moved to a closed position, the blades will tightly overlap each other and both sides of the outer frame to become sealed up. The operation of the ventilation damper assembly is done with a connecting rod that connects to the blades so that the turning angle of each blade is same. A pulling rod is further secured to one of the blades at a position along the line of pivots. By changing the position of the pulling rod, the blades can be turned from a completely open position to a completely closed position, and the open state of the ventilation damper assembly can be determined. Since the present invention of solar air conditioning system may be installed on roofs or high walls where most people cannot reach, such a pulling rod can be linked to a driving mechanism, such as a rope linking with the pulling rod and passing over a pulley, so that changing the blade position can be achieved by operating the rope.
Another advantage of this system is that the temperature of the heat-absorbing set can be automatically adjusted in accordance with the weather conditions. For example, in the scorching summer, when the outdoor temperature is very high, the required indoor air change rate will be the maximum, which maximizes the introduction of the cooled air into the buildings. Then, during winter when the required outdoor temperature is usually very low, the indoor air change rate will be the minimum, which minimizes the introduction of the cooled air into the buildings. Moreover, a high adjustability of air circulation is achieved by the easy controllability of the dampers located at an inlet gate (usually close to the floor) and an exhaust gate (usually close to the ceiling) and allows the indoor air change rate to be customized for a comfortable living environment.
The solar air conditioning system in accordance with the present invention can also be installed to the flat roof of steel-reinforced concrete (SRC) buildings. A better installation method is to fix this system on fixed boards. The boards can be firmly supported by iron frames with clearances between boards and the roof, while facing the sun. The sun-blocking effect caused by the present system will lower the roof temperature and the reduction of heat accumulated on the roof will be directly helpful for the buildings to save energy. In addition, this extra layer of protection on the roof means that the roof will not need too much work in respect to heat insulation.
The structure and objectives of the present invention can be more readily understood by persons skilled in the art from the following description of the preferred embodiments taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing a solar air conditioning system in accordance with the present invention.
FIG. 2A is a perspective view showing support boards used in a solar air conditioning system in accordance with the present invention.
FIG. 2B is a perspective view showing a heat-absorbing plate used in a solar air conditioning system in accordance with the present invention.
FIG. 2C is an enlarged view showing the area marked by the dotted lines illustrated in FIG. 2 B.
FIG. 3A is an assembly view showing a heat-absorbing unit used in a solar air conditioning system in accordance with the present invention.
FIG. 3B is a side view showing the fixing of a heat-absorbing unit used in a solar air conditioning system in accordance with the present invention.
FIG. 4A is a perspective view taken from Section A—A in FIG. 1 , wherein the solar collector assembly comprises a flat transparent panel.
FIG. 4B is a perspective view taken from Section A—A in FIG. 1 , wherein the solar collector assembly comprises a corrugated transparent panel.
FIG. 4C is a schematic view showing the fixing of a transparent panel of a solar air conditioning system in accordance with the present invention.
FIG. 5 is a schematic view showing an inlet assembly of a solar air conditioning system in accordance with the present invention.
FIG. 6 is a schematic view showing an outlet assembly of a solar air conditioning system in accordance with the present invention.
FIG. 7A is a schematic view showing a ventilation damper assembly installed in inlet and outlet assemblies used in a solar air conditioning system in accordance with the present invention.
FIG. 7B is a schematic view showing the way of remotely controlling the ventilation damper assembly shown in FIG. 7 A.
FIG. 7C is a partial sectional view of the ventilation damper assembly shown in FIG. 7 A.
FIG. 8A is a perspective view showing an alternative embodiment of a heat-absorbing unit used in a solar air conditioning system in accordance with the present invention.
FIG. 8B is a sectional view of the heat-absorbing unit in FIG. 8A , taken along Section A—A in FIG. 1 .
FIG. 9A is a perspective view showing a further embodiment of a heat-absorbing unit used in a solar air conditioning system in accordance with the present invention.
FIG. 9B is a sectional view of the heat-absorbing unit in FIG. 9A , taken along Section A—A in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic view of a solar air conditioning system in accordance with the present invention. The air conditioning system includes a solar collector assembly ( 20 ), an inlet assembly ( 21 ), and an outlet assembly ( 22 ). The solar collector assembly ( 20 ) forms the paths for heating air and further comprises a heat-absorbing set ( 17 ), a transparent panel ( 30 , 31 ) and a support base ( 14 ).
The heat-absorbing set ( 17 ) includes several black modular heat-absorbing units ( 10 ). As shown in FIGS. 2A to 2 C, a heat-absorbing unit ( 10 ) includes two pieces of support boards ( 1 ) and a piece of heat-absorbing plate ( 3 ). These boards and plate ( 1 , 3 ) are thin and handy for displaying, packaging, storage, transportation and assembly.
An elongated groove ( 2 ) is formed on the support board ( 1 ). The heat-absorbing plate ( 3 ) is formed with several heat-absorbing plate fixing holes ( 6 ) and several transparent panel fixing holes ( 7 ). Also, there is a pair of parallel grooves formed on the heat-absorbing plate ( 3 ), each comprising an elongated groove ( 4 ) that penetrates the plate ( 3 ) and a positioning groove ( 5 ) that does not. The length of the positioning groove ( 5 ) is substantially the same as that of the elongated groove ( 2 ) formed on the support board ( 1 ).
FIGS. 3A and 3B respectively illustrate the assembly view and the fixing of the heat-absorbing unit ( 10 ) of the solar air conditioning system. During the assembly, the elongated groove ( 2 ) formed on each support board ( 1 ) engages with the elongated groove ( 4 ) of the heat-absorbing plate ( 3 ) until the ends of the grooves ( 2 , 4 ) abut against each other, which allows the edge of the elongated grooves ( 2 ) of the support board ( 1 ) to be clamped and further fixed by the positioning grooves ( 5 ) of the heat-absorbing plate ( 3 ). Because the two elongated grooves ( 4 ) of the heat-absorbing plate ( 3 ) can be formed on the same side or the opposite sides, the insertion direction of the support board ( 1 ) can be adjusted according to the direction of the two elongated grooves ( 4 ) formed on the heat-absorbing plate ( 3 ).
In addition, after the heat-absorbing unit ( 10 ) is assembled, the portions of support boards ( 1 ) above and below the heat-absorbing plate ( 3 ) can further be defined as upper support boards ( 11 ) and lower support boards ( 12 ), respectively.
The modular heat-absorbing unit ( 10 ) shown in FIG. 3A can be flexibly arranged according to the users' requirements and the characteristics of roofs. The present invention thus can be applied to a larger variety of buildings than a conventional solar collector assembly can.
FIG. 3B shows the fixing of the heat-absorbing unit ( 10 ), which is achieved by rotating screws ( 15 ) through the pre-determined holes ( 6 ) formed on the heat-absorbing plate ( 3 ) and into the roof or the fixed boards ( 14 ). Furthermore, a more solid fixing can be achieved by inserting washers ( 16 ) between the screw caps and the heat-absorbing plate ( 3 ).
Placing several modular heat-absorbing units ( 10 ) on the roof or the fixed boards ( 14 ) paved with heat-insulated layers ( 13 ) can construct an ideal solar heat-absorbing set ( 17 ). FIGS. 4A and 4B are perspective views taken from Section A—A in FIG. 1 , showing sectional views of a solar collector assembly ( 20 ). In the embodiment shown in FIG. 4A , the panel for the solar collector assembly ( 20 ) is a transparent flat panel ( 30 ). In the embodiment shown in FIG. 4B , the panel for the solar collector assembly ( 20 ) is a transparent corrugated panel ( 31 ).
As shown in FIGS. 4A and 4B , multiple upper heat-absorbing channels ( 32 ) are formed between the panel ( 30 , 31 ) and the heat-absorbing plates ( 3 ). Multiple lower heat-absorbing channels ( 33 ) are formed between the heat-absorbing plates ( 3 ) and the heat-insulated layer ( 13 ). In order to reduce possible heat loss from the transparent panel ( 30 , 31 ), two approaches can be taken. The first approach is to close the entrances and exits of the upper heat-absorbing channels ( 32 ). The second approach is to reduce the height ratio of the upper support boards ( 11 ) to the lower support boards ( 12 ). Both approaches allow air to be heated mainly in the lower heat-absorbing channels ( 33 ). Therefore, though the present invention only has one layer of transparent panel ( 30 , 31 ), since most air goes through the lower heat-absorbing channels ( 33 ), the system demonstrates the excellent heat insulation effect of double-glazing and improves the heating efficiency.
FIG. 4C shows the fixing of a transparent panel ( 30 , 31 ) of the solar collector assembly ( 20 ). In order to fix the transparent panel ( 30 , 31 ) to the roof or the fixed boards ( 14 ) and protect the solar collector assembly ( 20 ) from the rain, it is necessary to first drill holes in the transparent panel ( 30 , 31 ) along the axis of the fixing holes ( 7 ) in the heat-absorbing plates ( 3 ), and then insert bushings ( 39 ) with soft washers ( 38 b ) through the holes in the transparent panels ( 30 , 31 ) and into the fixing holes ( 7 ) in the heat-absorbing plates ( 3 ) such that the end of the bushings ( 39 ) contact with the heat-insulated layer ( 13 ) or the fixed boards ( 14 ). Next, by inserting screws ( 36 ) equipped with hard washers ( 37 ) and soft washers ( 38 a ), through the bushings ( 39 ), and into the roof or the fixed boards ( 14 ) to lock the transparent panel ( 30 , 31 ) onto the roof or the fixed boards ( 14 ), the rain will be prevented from leaking into the solar collector assembly ( 20 ).
FIGS. 5 and 6 are schematic views of the inlet assembly ( 21 ) and the outlet assembly ( 22 ) of the solar air conditioning system in accordance with the present invention. As shown in FIGS. 1 , 5 and 6 , the inlet assembly ( 21 ) and the outlet assembly ( 22 ) have structures for communicating to the heat-absorbing channels ( 32 , 33 ) in the solar collector assembly ( 20 ).
As shown in FIGS. 1 and 5 , the inlet assembly ( 21 ) has a blank side ( 50 ) facing the heat-absorbing channels ( 32 , 33 ) in the solar collector assembly ( 20 ). Through this blank side ( 50 ), the inlet assembly ( 21 ) connects to the transparent panel ( 30 , 31 ) on the solar collector assembly ( 20 ) and such a connection is sealed. The inlet assembly ( 21 ) itself is fixed to the roof or the fixed boards ( 14 ) by means of locks ( 49 ). On both sides of the inlet assembly ( 21 ) are joints ( 23 ) for connecting to the indoor exhaust pipes and the communications therebetween are controlled by conventional dampers (not shown). However, one of the joints ( 23 ) may be chosen to be used according to the direction of the indoor exhaust pipes, and the other one will be closed by a plug (not shown).
Two joints ( 23 ) for connecting to the indoor exhaust pipes are linked by an air distributor ( 48 ). The distributor ( 48 ) is uniformly formed with drilled holes ( 51 ) on the side facing the heat-absorbing channels ( 32 , 33 ) of the solar collector assembly ( 20 ) to ensure that after air flows into the inlet assembly ( 21 ), it is uniformly distributed to heat-absorbing channels ( 32 , 33 ) so that the overall efficiency of heat absorption can be increased. In order to reduce the air flow resistance, the total area of the drilled holes ( 51 ) is preferably twice as large as the cross-sectional area of the joints ( 23 ) connecting to the indoor exhaust pipes. The inlet assembly ( 21 ) further has an air inlet side ( 24 ) that communicates to paths leading to the outdoors. The air inlet side ( 24 ) is opposite to the heat-absorbing channels ( 32 , 33 ). In addition, the air inlet side ( 24 ) is formed with several pre-set openings ( 41 ) for receiving several modular ventilation damper assemblies ( 40 ) by fixing the flanges ( 42 ) thereof to the rim of the pre-set openings ( 41 ) so as to control the opening and closing of the air inlet side ( 24 ). The sizes of the pre-set openings ( 41 ) on the air inlet side ( 24 ), as well as the number of the ventilation damper assemblies ( 40 ), are determined by the size of the solar collector assembly ( 20 ). The structure of the ventilation damper assembly ( 40 ) will be further described below in accordance with FIG. 7 .
FIG. 6 is a schematic view showing the outlet assembly ( 22 ) of the solar air conditioning system in accordance with the present invention. As shown in FIGS. 1 and 6 , the outlet assembly ( 22 ) has a blank side ( 50 ) facing the heat-absorbing channels ( 32 , 33 ) in the solar collector assembly ( 20 ). Through this blank side ( 50 ), the outlet assembly ( 22 ) connects to the transparent panel ( 30 , 31 ) on the solar collector assembly ( 20 ) and such a connection is sealed. The outlet assembly ( 22 ) itself is fixed to the roof or the fixed boards ( 14 ) by means of locks ( 49 ). On both sides of the outlet assembly ( 22 ) are joints ( 25 ) for connecting to the indoor inlet pipes and the communications therebetween are controlled by conventional dampers (not shown). Similar to the joints ( 23 ) of the inlet assembly ( 21 ), one of the joints ( 25 ) may be chosen to be used according to the direction of the indoor inlet pipes, and the other one will be closed by a plug (not shown).
Two joints ( 25 ) for connecting to the indoor inlet pipes are also linked by an air distributor ( 48 ). The distributor ( 48 ) is uniformly formed with drilled holes ( 51 ) on the side facing the heat-absorbing channels ( 32 , 33 ) of the solar collector assembly ( 20 ) to ensure that air is uniformly distributed to the heat-absorbing channels ( 32 , 33 ) so that the overall efficiency of heat absorption can be increased. The outlet assembly ( 22 ) further has an upward air exhaust side ( 26 ) that communicates to paths leading to the outdoors. In addition, the air exhaust side ( 26 ) is formed with several pre-set openings ( 41 ) for receiving several modular ventilation damper assemblies ( 40 ) by fixing the flanges ( 42 ) thereof to the rim of the pre-set openings ( 41 ) so as to control the opening and closing of the air exhaust side ( 26 ). The size of the pre-set opening ( 41 ) on the air exhaust side ( 26 ), as well as the number of the ventilation damper assemblies ( 40 ), are determined by the size of the solar collector assembly ( 20 ). Moreover, in order to prevent rain from getting into the outlet assembly ( 22 ), a transparent canopy ( 27 ) can be disposed above the air exhaust side ( 26 ).
As shown in FIGS. 5 and 6 , the structure of the outlet assembly ( 22 ) is similar to that of the inlet assembly ( 21 ), except that: firstly, the ventilation damper assembly ( 40 ) of the outlet assembly ( 22 ) faces upwards; secondly, the outlet assembly ( 22 ) needs an additional rain-proof canopy ( 27 ) to prevent rain from leaking into the ventilation damper assembly ( 40 ); and thirdly, on both sides of the outlet assembly ( 22 ) are joints ( 25 ) for connecting to the indoor inlet pipes.
FIGS. 7A to 7 C are schematic views of the ventilation damper assembly ( 40 ) used in the inlet assembly ( 21 ) and the outlet assembly ( 22 ) shown in FIG. 5 and FIG. 6 . As shown in FIGS. 7A and 7B , the ventilation damper assembly ( 40 ) is disposed to the pre-set openings ( 41 ) of the inlet assembly ( 21 ) and the outlet assembly ( 22 ) by flanges ( 42 ) thereof.
As shown in FIG. 7B , the basic structure of the ventilation damper assembly ( 40 ) comprises multiple rectangular blades ( 44 ) which have a wing-shaped cross-sectional profile and are mounted on the parallel pivots ( 45 ). The pivots ( 45 ) are in turn supported on both sides of a rectangular outer frame ( 43 ) by means of shaft bearings ( 46 ).
The opening and closing of the ventilation damper assembly ( 40 ) is done with a connecting rod (not shown) that connects to the blades ( 44 ) so that the turning angle of each blade ( 44 ) is the same. A pulling rod ( 52 ) is further secured to a pivot ( 45 ) of one of the blades ( 44 ). By changing the position of the pulling rod ( 52 ), the blades ( 44 ) can be turned from a completely open position to a completely closed position, and the open state of the ventilation damper assembly ( 40 ) can be determined. As shown in FIG. 7C , to ensure that while in the completely closed position, the blades ( 44 ) have sufficient tightness with both sides of the outer frame ( 43 ), the outermost end of each pivot ( 45 ) is provided with a threaded section ( 53 ) which extends out of the shaft bearing ( 46 ). By adjustably engaging a locking nut ( 47 ) with the threaded section ( 53 ), the gap between an end of the blade ( 44 ) and a side of the outer frame ( 43 ) can be minimized such that air leakage can be reduced in the completely closed position. In addition, a screen ( 35 ) can be provided on the outer frame ( 43 ) of the ventilation damper assembly ( 40 ), facing the heat-absorbing channels ( 32 , 33 ), so as to prevent dust and insects from entering the assembly ( 40 ). Moreover, since the present invention of the solar air conditioning system may be installed on roofs or high walls where most people cannot reach, a pulling rod ( 52 ) can be linked to a drive mechanism, such as a rope ( 55 ) linking with the pulling rod ( 52 ) and passing over a pulley ( 54 ), so that changing the blade ( 44 ) position can be achieved by operating the rope ( 55 ), as shown in FIG. 7 B.
Based on the above structures, by respectively connecting the joint ( 23 ) of the inlet assembly ( 21 ) and the joint ( 25 ) of the outlet assembly ( 22 ) to the indoor exhaust pipe and the indoor inlet pipe, and switching and adjusting the opening and closing of the air inlet side ( 24 ) and air exhaust side ( 26 ) communicating to the paths leading to the outdoors, the best air conditioning effect can be achieved, which is explained as follows:
In summer and hot weather time, the communication between the joint ( 23 ) of the inlet assembly ( 21 ) and the indoor exhaust pipe is opened and the ventilation damper assemblies ( 40 ) arranged on the air inlet side ( 24 ) of the inlet assembly ( 21 ) are closed. Further, the communication between the joint ( 25 ) of the outlet assembly ( 22 ) and the indoor inlet pipe is closed and the ventilation damper assemblies ( 40 ) arranged on the air exhaust side ( 26 ) of the outlet assembly ( 22 ) are opened. Accordingly, the solar collector assembly ( 20 ) heats the air flowing from the indoor exhaust pipe through the joint ( 23 ) and the heated air expels the indoor air out of the buildings due to the chimney effect caused by the thermal buoyancy generated by the heated air. At this moment, if an inlet gate which introduces the air from the outdoors is located at a cold position or the air introduced from the outdoors is cooled, the present solar air conditioning system can achieve the effect of air conditioning with cooled air circulation.
In winter and cold weather time, the communication between the joint ( 23 ) of the inlet assembly ( 21 ) and the indoor exhaust pipe is opened and the ventilation damper assemblies ( 40 ) arranged on the air inlet side ( 24 ) of the inlet assembly ( 21 ) are closed. Further, the communication between the joint ( 25 ) of the outlet assembly ( 22 ) and the indoor inlet pipe is opened and the ventilation damper assemblies ( 40 ) arranged on the air exhaust side ( 26 ) of the outlet assembly ( 22 ) are closed. Accordingly, the solar collector assembly ( 20 ) heats the air flowing from the indoor exhaust pipe through the joint ( 23 ) and the heated air flows into the indoor inlet pipe through the joint ( 25 ) so as to heat the indoor space, which can be speeded up by a fan or a blower associated with the indoor inlet pipe. However, if fresh air is to be introduced from the outdoors and heated together with the air from the indoor exhaust pipe, so as to save energy and keep the indoor air fresh, the communication between the joint ( 23 ) of the inlet assembly ( 21 ) and the indoor exhaust pipe is opened and the ventilation damper assemblies ( 40 ) arranged on the air inlet side ( 24 ) of the inlet assembly ( 21 ) should be opened to a desired position.
The present solar air conditioning system can be installed to work with a conventional solar hot water supply system for all seasons, which is achieved by placing heat-absorbing water pipes of the hot water system into the upper heat-absorbing channels ( 32 ) of the present invention, and then sending the heated water back to the water circulation circuit (not shown) made of the heat storage tank. The circulated air is heated primarily at the lower heat-absorbing channels ( 33 ) of the present invention to reduce heat loss from the transparent panels ( 30 , 31 ).
FIGS. 8A and 8B respectively show a perspective view showing an alternative embodiment of a heat-absorbing unit ( 8 ) used in a solar air conditioning system in accordance with the present invention and a sectional view of the heat-absorbing unit in FIG. 8A , taken along Section A—A in FIG. 1 . As shown in FIG. 8A , the heat-absorbing unit ( 8 ) is made of a thin metal plate with the surface thereof painted or coated black, allowing it to serve as the heat-absorbing plate ( 3 ). The heat-absorbing unit ( 8 ) is partially in an arc or reverse U shape and the two sides of the unit ( 8 ) are webs for attaching the unit ( 8 ) onto the fixed board ( 14 ) under the solar collector assembly ( 20 ). The flat webs are formed with the heat-absorbing plate fixing holes ( 6 ). The top of the heat-absorbing unit ( 8 ) is formed with the transparent panel fixing holes ( 7 ). The way of fixing the transparent panels ( 30 , 31 ) is similar to that shown in FIG. 4 C. Further, as shown in FIG. 8B , multiple heat-absorbing units ( 8 ) have their two flat webs overlapping those of the neighboring units ( 8 ) with the heat-absorbing plate fixing holes ( 6 ) aligned. The heat-absorbing units ( 8 ) are then firmly fixed to the fixed boards ( 14 ) by inserting screws through the holes ( 6 ) and into the fixed boards ( 14 ), and form several fluid cross sections in the heat-absorbing set ( 17 ). Together with the transparent panels ( 30 , 31 ) and the fixed board ( 14 ), the heat-absorbing set ( 17 ) forms smaller upper heat-absorbing channels ( 32 ) and larger lower heat-absorbing channels ( 33 ) in the solar collector assembly ( 20 ). The lower heat-absorbing channels ( 33 ) benefit from the heat-insulated effect as double-glazing, and a high efficiency of heat absorption.
FIGS. 9A and 9B respectively show a perspective view showing a further embodiment of a heat-absorbing unit ( 9 ) used in a solar air conditioning system in accordance with the present invention and a sectional view of the heat-absorbing unit in FIG. 9A , taken along Section A—A in FIG. 1 . As shown in FIG. 9A , the heat-absorbing unit ( 9 ) is made of an angled thin metal plate with the surface thereof painted or coated black, allowing it to serve as the heat-absorbing plate ( 3 ). Two sides of the unit ( 9 ) for attaching the unit ( 9 ) onto the fixed board ( 14 ) under the solar collector assembly ( 20 ), are formed with the heat-absorbing plate fixing holes ( 6 ). The top of the heat-absorbing unit ( 9 ) is formed with the transparent panel fixing holes ( 7 ). The way of fixing the transparent panels ( 30 , 31 ) is similar to that shown in FIG. 4 C. Further, as shown in FIG. 9B , multiple heat-absorbing units ( 9 ) are firmly fixed to the fixed boards ( 14 ) by inserting screws through the holes ( 6 ) and into the fixed boards ( 14 ), and form several fluid cross sections in the heat-absorbing set ( 17 ). Together with the transparent panels ( 30 , 31 ) and the fixed board ( 14 ), the heat-absorbing set ( 17 ) forms smaller upper heat-absorbing channels ( 32 ) and larger lower heat-absorbing channels ( 33 ) in the solar collector assembly ( 20 ). The lower heat-absorbing channels ( 33 ) benefit from the heat-insulated effect as double-glazing, and a high efficiency of heat absorption.
The solar air conditioning system in accordance with the present invention has many features that are superior to those of conventional solar air conditioning systems. Adapting the concept of a modular design, the present invention provides buildings with a greater compatibility in application. Moreover, the present invention provides users with more selection and freedom in assembly. The present invention can be installed to all kinds of buildings, including ones that are under construction or currently existing ones. It can be installed horizontally or vertically attached to walls. Furthermore, it can be installed at an angle. The present invention can also provide excellent heat insulation and protection to the buildings.
The heat-absorbing units used in the present invention can be flexibly expanded as desired to the most optimal absorption surface areas to fully receive and collect energy. Therefore, the present invention does not need a fixed outer frame insulation chamber like the one used in the conventional design. The present invention also needs no special consideration for the heat efficiency of each individual unit, as conventional models do. One special feature of the present invention is that although it only has one layer of transparent panel in its structure, because most air goes through the lower heat-absorbing channels, the system has the excellent insulation effect of a double-glazed system and a very high heat-absorbing efficiency.
Compared with the conventional model, the present invention has a lighter and thinner structure and appearance, and thus it does not cause any burden to the buildings. The commercially available flat transparent panels and corrugated transparent panels can maintain the harmony and aesthetics of the existing buildings. At the same time, the transparent panels can provide protection to the roof while serving as the double-glazed transparent panels for the solar collector assembly. Further, since the installation of the transparent panels does not have to be glazed into the outer frame of the heat-insulated chamber as one must in the conventional model, the thermal expansion coefficient of materials used in the present invention will not cause thermal stress problems related to deformation or cracking.
The present solar air conditioning system is designed in a modular concept. It can greatly reduce costs because the heat-absorbing units are made of thin boards and plates, and are much simpler compared to the conventional system with a whole-unit design. The present system not only saves costs in packaging but also requires less room for display and storage to make channel marketing much easier. It is very easy to install and maintain such a system. Moreover, users can try to install or assemble the system by themselves.
The above descriptions have clearly illustrated the important features, operational methods and applications of the present invention. Although the invention has been described with reference to the preferred embodiments, it will be obvious to persons skilled in the art that various changes and modifications may be made without departing from the scope of the invention as recited in the claims.
Sequence Listing
1
support board
2
elongated groove
3
heat-absorbing plate
4
elongated groove
5
positioning groove
6
heat-absorbing plate fixing hole
7
transparent panel fixing hole
8
heat-absorbing unit
9
heat-absorbing unit
10
heat-absorbing unit
11
upper support board
12
lower support board
13
heat-insulated layer
14
support base (roof or fixed boards)
15
screw
16
washer
17
heat-absorbing set
20
solar collector assembly
21
inlet assembly
22
outlet assembly
23
joint connected to the indoor exhaust pipe
24
air inlet side
25
joint connecting to the indoor inlet pipe
26
air exhaust side
27
rain-proof canopy
30
flat transparent panel
31
corrugated transparent panel
32
upper heat-absorbing channel
33
lower heat-absorbing channel
35
screen
36
screw
37
hard washer
38a
soft washer
38b
soft washer
39
bushing
40
ventilation damper assembly
41
pre-set opening
42
flange
43
outer frame
44
blade
45
pivot
46
shaft bearing
47
locking nut
48
air distributor
49
lock
50
blank side
51
drilled hole
52
pulling rod
53
threaded section
54
pulley
55
rope
|
This invention provides buildings with a modular air conditioning system that utilizes solar energy for heating air. This invention contains a solar collector assembly, an inlet assembly and an outlet assembly. The solar collector assembly further comprises a transparent panel, a heat-absorbing set and a support base, and forms paths for heating the air, wherein the heat-absorbing set is made of several simple, light-weight modular heat-absorbing units to form several heat-absorbing channels. Such a design not only can fully utilize the heat-absorbing space on the roof and save the cost for being displayed in marketing channels, but also can be constructed by the users in accordance with their own needs, so as to save cost in modularization. The inlet and outlet assemblies communicate to the heat-absorbing channels in the solar collector assembly and are respectively connected to the pipes and paths leading into and out of the buildings. By switching and adjusting the openings of these pipes and paths, in winter, the preheated air will be introduced into buildings; and in summer, the hot indoor air will be expelled out of the buildings and fresh air will be guided into the buildings. As a result, a more economical air conditioning system is formed.
| 5
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates, in general, to the remediation of contaminated soil and groundwater. It relates to an in situ method and apparatus to deliver chemical reagents that serve to degrade and/or enhance recovery of organic contamination in soil and groundwater.
2. History of the Related Art
Contamination of subsurface soil and groundwater from the release of hazardous substances has become a significant problem in populated and industrialized areas of the world. The contamination stems from intentional or unintentional releases of hazardous substances from above- and below-ground storage vessels such as tanks and conveyance piping, materials handling practices such as degreasing and other cleaning operations, and other product transfer operations. The released products that are in themselves hazardous or contain hazardous constituents include: petroleum products such as gasoline, diesel fuel, heating oil, jet fuel, and a variety of lubricants; halogenated solvents such as perchloroethylene, trichloroethylene, and freons; and non-halogenated solvents such as hexane, benzene, and ether.
The releases of these substances to the ground surface or into the subsurface presents a risk of human exposure that is unacceptable for human health and ecological factors. Many of the contaminants are known carcinogens and excessive exposure to them has been shown to increase the probability of contracting certain diseases including various forms of cancer. Potential human exposure routes include: inhalation of the volatile contaminant species which can occur as the contaminants in soil and groundwater evaporate into breathing zones; incidental ingestion of contaminated soil; and ingestion of or dermal contact with contaminated groundwater from a potable drinking water well. In response to these concerns, federal, state, and local governments have enacted environmental legislation requiring property owners to investigate and remediate their properties that contain contaminated soil and/or groundwater.
Many techniques have been developed and used over the past two decades to remove or destroy contaminants in soils and groundwater. Early forms of remediation included excavation of contaminated soil for landfill disposal and extraction of contaminated groundwater from wells, above ground treatment followed by discharge to a sewer system or reapplication at the subsurface. Because these methods generally involved substantial financial expenditure and were mostly ineffective, more advanced, in situ methods and techniques of treatment have been developed. These in situ methods include bioremediation, surfactant flushing, and chemical oxidation.
Bioremediation techniques rely on the stimulation of naturally-occurring subsurface bacteria or augmentation with foreign bacteria that, in turn, metabolize the subsurface organic contamination thereby reducing the concentration of the contaminant in soils and groundwater. The effectiveness of in situ bioremediation techniques relies on the uniform and comprehensive delivery of reagents such as inorganic nutrients, oxygen, and bacteria to the region of the subsurface targeted for treatment. Typically, reagent delivery has been accomplished through wells, irrigation trenches, injection lances, or french drains, all of which are established by prior art. Through numerous applications of bioremediation techniques at contaminated sites, it has been shown that these means to deliver reagents do not provide an effective system to supply the necessary reagent flow. Further, each well can reach only a limited volume of soil and groundwater, and, therefore, a large number of the wells, trenches, etc., must be emplaced at a site in order to address an entire contaminated soil or groundwater volume.
Surfactant flushing techniques rely on the delivery of a reagent to the subsurface that serves to reduce the surface tension of organic contaminants which are adhered to soil particle surfaces (commonly referred to as “adsorbed contamination”) or trapped in the interstitial spaces between soil particles (commonly referred to as “absorbed contamination”). When the delivered chemical reagent (surfactant) contacts the absorbed or adsorbed contaminants (collectively referred to as “sorbed contaminants”) the sorption forces are reduced, thereby increasing the mobility of the contaminant which, in turn, increases its ability to be collected and extracted by groundwater extraction (pumping) techniques. Once again, effective application of this technique relies heavily on the delivery device since the surfactant reagent must contact all portions of the soil and groundwater volume that contains the organic contaminant. As with other in situ techniques, surfactant flushing relies on conventional chemical reagent delivery devices such as wells, trenches, injection lances, and french drains to effect emplacement of the surfactant solution. Experience with these devices has again demonstrated that their ability to effect reagent delivery to any significant volume of soil or groundwater surrounding the device is limited since they rely solely on gravitational forces, which may be enhanced by pressurizing the reagent fluid. These apparatus do not promote mixing and turbulence needed to adequately disperse the reagent fluid.
Similarly, chemical oxidation techniques using hydrogen peroxide, Fenton's Reagent (a combination of hydrogen peroxide, acid, and metal salts) as discussed in Hawley's Condensed Chemical Dictionary, 11 th Edition, Van Nostrand Reinhold, Publishers, 1987, potassium permanganate, sodium permanganate, and ozone rely on the delivery of reagents to the subsurface using wells, trenches, injection lances, or french drains. In addition to their limited effectiveness in comprehensively and economically delivering the required reagents, the use of these conventional delivery techniques can result in dangerous pressure buildup within these devices because of the pressure and heat generated by the reactions that result from chemical oxidation of the contaminants by the supplied oxidation reagents. Generally, a substantial quantity of the oxidizing fluid, in relatively high concentrations (15% to 50% by weight in aqueous form) is needed to effect the desired decomposition of the organic contaminants. Experience with the application of these quantities and concentrations of oxidizing fluids has shown that undesired consequences occur. For example, without adequate dispersement of the reagents from the application apparatus into the surrounding soil and groundwater matrix, the oxidizing fluid can: (1) react with itself, producing large quantities of oxygen gas, which, in combination with the vaporized organic constituent, produce dangerous, explosive conditions; (2) lead to inefficient use of the oxidizing solution; and (3) can cause runaway overpressurization of the apparatus leading to sudden blowout of the apparatus, its components, and/or soil and groundwater surrounding the apparatus.
SUMMARY OF THE INVENTION
The present invention relates to an apparatus to effectively deliver chemical reagents to the subterranean environment in a uniform, comprehensive manner, to enhance mixing and lateral and vertical dispersion of the reagents to the soil and groundwater surrounding the apparatus. The chemical reagents delivered by the apparatus include those capable of oxidizing, degrading, or enhancing solubility and mobility organic contaminants sorbed to soils or dissolved in groundwater. The method and apparatus which comprises the present invention accomplishes remediation of soil and groundwater contaminated with undesirable organic compounds by overcoming deficiencies in the art with respect to the delivery of the reagents needed to bring about oxidation, degradation, or solubility and mobility enhancement.
The invention method includes the installation of a plurality of recirculating reagent delivery devices or wells into the subsurface, injection of select chemical reagents into each of the recirculating wells, and recirculation of the reagent/groundwater mixture between the recirculating reagent delivery device and the surrounding soil/groundwater matrix to enhance distribution and mixing of the reagent/groundwater mixture. The apparatus associated with the present invention is the recirculating reagent delivery device. The device consists of: a borehole extending vertically into the subterranean strata; a cylindrical casing centered within the borehole and extending from the ground surface to near the bottom of the borehole; a perforated or screened (permeable) section of the cylindrical casing located near the bottom of the casing to allow reagents to flow outward from the casing or allow groundwater to flow into the casing; a second permeable section of the cylindrical casing located above the lower permeable section to allow either groundwater to flow into the casing or allow supplied reagents to flow out of the casing into the surrounding groundwater body; a reagent delivery string located within the casing and extending to either the upper or lower permeable sections of the cylindrical casing; and reagent mixing, storage, and supply equipment located at the ground surface and attached to the reagent delivery string.
There are two forms of the device in order to address organic contaminants that are denser than groundwater, known as dense, non-aqueous-phase liquids (DNAPL), and organic contaminants that are less dense than groundwater, known as light, non-aqueous-phase liquids (LNAPL). The design of each form of the device (the forced mode and the lift mode, respectively) allows for delivery of the reagents to the region of the groundwater body that is likely to contain a greater concentration or mass of the contaminant. Specifically, the forced mode form of the device is designed to deliver reagents to a greater depth while receiving groundwater for recirculation from a shallow depth because DNAPL contaminants tend to sink, or migrate downward, to greater depths of the groundwater body. Conversely, the lift mode of the device, constructed and operated to address LNAPL contaminants, delivers reagents to the upper portion of the groundwater body, while receiving groundwater from the deeper portion of the groundwater body for recirculation.
The forced mode form of the device is designed and constructed such that the upper and lower permeable sections of the casing are separated by a pump. Groundwater enters the casing through the upper permeable section and is forced by the pump through the lower permeable section and into the groundwater body surrounding the lower permeable section. Reagents are added to the groundwater at the discharge end of the pump through a reagent feed string so that they, in addition to the groundwater, are delivered to the groundwater body surrounding the lower permeable section of the casing.
The lift form of the device is designed and constructed such that the reagent feed string extends to the top of the lower permeable section. Reagents, such as potassium permanganate, Fenton's Reagent, hydrogen peroxide, ozone, surfactants, or biological nutrients, are pumped into the reagent delivery string, along with a transport medium such as water or compressed air, and emerge in the cylindrical casing, react with dissolved organic contaminants in the groundwater causing gas to form (or, in the case of surfactant, nutrient, or ozone reagents, the supplied air) lifting the fluid in the casing to the upper screened or permeable area, causing the fluid/gas mixture to emerge from the upper portion of the casing and into the surrounding soil/groundwater matrix. The loss of the fluid from the casing allows additional groundwater to flow into the lower screened or permeable section establishing the circulation process which continues as long as reagents are added through the string. The downward motion of the fluid emerging from the upper screen, coupled with the inward motion of groundwater being drawn into the lower screen, creates a torroidal circulation pattern which serves to enhance mixing, reagent distribution, and sorbed contaminant dissolution.
The chemical reactions associated with the use of oxidation reagents, in particular, can generate heat and unwanted vapor containing volatile species of organic contaminants. In cases when this vapor generation is likely (when volatile organic species are present in the groundwater), a vacuum can be applied to the cylindrical casing by a vacuum pump so that the vapor can be evacuated and either discharged to the atmosphere or can be treated with conventional vapor treatment techniques (carbon adsorption, catalytic oxidation, and the like) prior to atmospheric discharge. The applied vacuum also serves to reduce pressures within the freeboard region of the cylindrical casing and within the soils surrounding the device above the groundwater table. The pressure reduction reduces the danger of eruptions of soils and delivery system components that have been experienced by others practicing in situ chemical oxidation procedures using wells, injection lances, trenches, and french drains.
BRIEF DESCRIPTION OF THE DRAWINGS
The principles of the present invention can be readily illustrated by the accompanying drawings together with the detailed description that follows and wherein:
FIG. 1 is a cross-sectional view of the recirculation-enhanced reagent delivery system in lift mode; and.
FIG. 2 is a cross-sectional view of the recirculation-enhanced reagent delivery system in force mode.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 and 2 show the cross-section of the two forms of the recirculation-enhanced reagent delivery device in lift mode form for application to organic contamination that is less dense than groundwater and the force mode form for application to organic contaminants that are denser than groundwater, respectively.
The following description relates to construction of both forms of the device as shown in FIGS. 1 and 2. Common to both forms of the device is the emplacement of a vertical borehole 10 by drilling methods well known in the current art. Borehole 10 extends to below groundwater table surface 11 to a depth below the level of organic contamination that is desired to be addressed by the device. Delivery system riser 12 is inserted and centered in borehole 10 . Delivery system riser 12 consists of the following tubular sections with a diameter less than that of borehole 10 : impermeable riser sections 13 and 15 ; permeable riser sections 14 and 16 ; impermeable end cap 17 ; and riser head assembly 18 .
Annular space between borehole 10 and riser 12 is filled with filter material 19 , sealing material 20 , and stabilization material 21 . Filter material 19 is installed in the annular space from the bottom of borehole 10 to a depth near the top of the permeable riser section 16 and between the depths approximately coinciding with permeable riser section 14 . Filter material 19 can be any permeable material (such as sand or gravel) that retains or restricts the transport of fine particulates. Sealing material 20 is installed in the annular space between the depths coinciding with the bottom portion of impermeable riser section 13 and between the depths coinciding with impermeable riser section 15 . Sealing material can be any impermeable material that can provide a liquid-tight seal between borehole 10 and impermeable riser sections 13 and 15 such as bentonite or a bentonite-cement mixture. Stabilization material 21 is installed in the remaining annular space between borehole 10 , impermeable riser section 13 , and the top of sealing material 20 . Stabilization material can be any load-bearing material (such as cement or concrete) that restricts lateral movement of riser 12 within borehole 10 .
The following description relates to the construction and operation of the lift form of the device as shown in FIG. 1 . Riser head assembly 18 and end cap 17 are affixed to the top and bottom of riser 12 , respectively. Assembly 18 and end cap 17 restrict permeability of riser 12 to only permeable riser sections 14 and 16 , reagent delivery string 22 , and gas collection vent 23 . Reagent delivery string 22 is a tubular material of less diameter than riser 12 , passes from the ground surface through head assembly 18 , and extends to a depth coinciding approximately with the bottom of impermeable riser section 15 . Reagent delivery string 22 is attached to reagent supply vessel 24 which contains reagent solution 25 . Supply vessel 24 is attached to an air pump or compressor 26 by an air supply line 27 . Air supply line 27 includes a branch connection that is also attached to reagent delivery string 22 . In this configuration, air pump 26 can supply compressed air either to reagent supply vessel 24 for pressurized delivery of reagents to reagent delivery string 22 or deliver compressed air directly to reagent delivery string 22 . The selection of compressed air delivery is made by manipulation of flow control valves 28 , 29 , and 30 . For delivery of reagents to reagent delivery string 22 , control valves 28 and 29 are in the open or throttled position while control valve 30 is in the closed position. Conversely, for delivery of compressed air directly to the reagent delivery string, control valves 28 and 29 are closed while control valve 30 is open or throttled. Gas collection vent 23 is attached to riser head assembly 18 which is attached to ventilation pump 31 which may ventilate gas to the atmosphere or may attach to subsequent treatment equipment commonly known and described in the prior art.
Operation of the lift form of the device is first accomplished by adding reagent solution 25 to reagent supply vessel 24 . Reagent solution 25 may be aqueous solutions, including: acids, metal salt solutions (such as ferrous sulfate), and peroxides that comprise a Fenton's Reagent application; permanganate solutions for direct oxidation of organic contaminants in the groundwater; or surfactant solutions to enhance desorption and dissolution of organic contaminants sorbed to soils surrounding the borehole. Reagent solution 25 may be a gaseous solution such as ozone, oxygen, or a mixture thereof, in which case reagent supply vessel 24 would be a ozone and/or oxygen generation device commonly known and described in the prior art. The utilization of the reagent delivery device may include some or all of these reagents added simultaneously or in series in order to accomplish the desired organic contaminant destruction or removal.
After reagent solution 25 has been added to reagent supply vessel 24 , operation of the lift form of the device is continued by providing compressed air directly to reagent delivery string 22 to establish groundwater circulation. Compressed air emerges from the end of reagent delivery string 22 and flows upward by gravitational forces within groundwater contained in riser 12 , increasing height of fluid/air column within riser 12 . Groundwater/air mixture then passes out of riser 12 through permeable riser section 14 . The corresponding rise in height of the groundwater table surface 11 causes additional groundwater to flow toward and into riser 12 through permeable riser 16 . The resulting flow out of riser 12 through permeable riser section 14 and into riser 12 through permeable riser section 16 causes a torroidal, recirculation pattern to develop in the groundwater body surrounding borehole 10 as desired and contemplated by this invention. Compressed air that emerges from the groundwater/air mixture in riser 12 near permeable riser section 14 can pass upward and out of riser 12 through gas collection vent 23 . Because organic contamination that is volatile will tend to be transferred from groundwater into the compressed air steam as it passes through impermeable riser section 15 , the air stream emerging from vent 23 may require collection and treatment. In these cases, the device is equipped with standard vapor treatment equipment such as granular activated carbon, catalytic oxidation, or other techniques described in the prior art.
With the groundwater recirculation patterns fully developed through the addition of compressed air to reagent delivery string 22 , valves 28 , 29 , and 30 are manipulated such that compressed air flow is to reagent supply vessel 24 , causing reagent solution 25 to flow through reagent supply string 22 for a time period sufficient to delivery the contents of vessel 24 . Control valves 28 , 29 , and 30 are manipulated to allow compressed air to flow to reagent delivery string 22 and effect circulation of previously supplied reagents into the groundwater body surrounding borehole 10 . This procedure continues until all the desired reagent solutions and solution volumes have been delivered.
The following description relates to the construction and operation of the force mode of the reagent delivery device. As shown in FIG. 2, the construction of the force mode form differs from the lift mode form with installation of reagent mixing chamber 32 and force pump 33 . Chamber 32 serves to: provide hydraulic separation between permeable riser sections 14 and 16 ; connect the outlet of reagent delivery string 22 , and provide a connection for force pump 33 . Force pump 33 accepts groundwater that enters riser 12 through permeable riser section 14 and increases its pressure such that it is forced, along with the liquid or gaseous reagents 25 supplied through reagent delivery string 22 , out of riser 12 through permeable riser section 16 . Operation of the force mode of the reagent delivery device is similar to that of the lift mode except that the roles of the permeable riser sections are reversed, resulting in the groundwater/reagent mixture being forced out of riser 12 through permeable riser section 16 and groundwater to flow into riser 12 through permeable riser section 14 .
Using the procedures and apparatus of the invention, subsurface areas of up to approximately fifty feet from the borehole may be treated.
The foregoing description of the preferred embodiment of the invention has been presented to illustrate the principles of the invention and not to limit the invention to the particular embodiment illustrated. It is intended that the scope of the invention be defined by all of the embodiments encompassed within the following claims and their equivalents.
|
Method and apparatus for delivery of chemical reagents to a subterranean body of soil and groundwater to destroy or enhance mobility of organic compounds using a riser insertable in a borehole having spaced permeable sections separated by a non-permeable section and wherein the reagents are introduced from a source by a pressurization apparatus.
| 4
|
FIELD OF INVENTION
[0001] The present invention relates to the use of aqueous sodium hydroxide (NaOH)/thiourea solution, specifically to the use of aqueous NaOH/thiourea solution in pilot-scale production of cellulose products, wherein said cellulose products comprise composite fibers and/or functional materials of protein/cellulose, chitin/cellulose, Konjac Glucomannan/cellulose, nano-crystal particle/cellulose, etc. The present invention pertains to the field of natural macromolecules, and also to the fields of material, textile, chemistry and chemical engineering, agriculture and environmental engineering.
BACKGROUND OF THE INVENTION
[0002] Celluloses are the most abundant renewable resource on the earth and are environmentally friendly materials, so sufficient utilization of celluloses can not only protect environment but also save the limited unrenewable petroleum resources. However, celluloses are currently far from being sufficiently utilized in chemical industry, mainly because the current processes for dissolving cellulose are complex, costly and pollutive.
[0003] In the past one hundred years, conventional viscose process has been used for producing regenerated cellulose products such as rayon, glassine paper and the like. The conventional viscose process comprises reacting cellulose with CS 2 (33 wt %) in the presence of strong base (the concentration of sodium hydroxide being 18 wt %) to produce cellulose xanthate that is dissolved in the alkaline solution to form a viscose solution, and then spinning or casting the viscose solution of cellulose, followed by regenerating in diluent acid solution to obtain viscose fiber (rayon) or glassine paper. A great quantity of toxic gases such as CS 2 and H 2 S which severely pollute environment are released during the process and are harmful to human health (J. Macromol. Sci.-Rev. Macromol. Chem., 1980, C18 (1), 1).
[0004] In the prior art, the cuprammonium process for producing cuprammonium rayon also has drawbacks of environmental pollution, high cost and difficulty to recover solution. The processes in which other organic or inorganic solvents such as dimethylsulfoxide-nitrogen oxide (U.S. Pat. No. 3,236,669, 1966), aqueous ZnCl 2 solution (U.S. Pat. No. 5,290,349, 1994), LiCl/DMAc (U.S. Pat. No. 4,302,252, 1981) and the like are used, respectively, are difficult in industrialization due to the cost and their complicated dissolving procedures.
[0005] N-methylmorpholine oxide (NMMO) (U.S. Pat. No. 2,179,181, 1939; U.K. Patent No. GB1144048, 1967; U.S. Pat. No. 4,246,221, 1981) is considered as the most promising solvent for cellulose so far. In 1989, Bureau International pour la Standardisation des Fibres Artificielles (BISFA) in Brussels named cellulose fibers made by such NMMO process as “Lyocell”. Although a small amount of products of cellulose fibers made thereby had been marketed, the industrial production of them developed slowly due to high cost and high spinning temperature.
[0006] In addition, a process had been proposed that comprises reacting cellulose with urea at high temperature to obtain cellulose carbamate, and then dissolving directly in a diluent alkaline solution to obtain spinning solution (Finland Patent No. FI61003; Finland Patent No. FI62318; U.S. Pat. No. 4,404,369). However, this process requires a great amount of urea, leads to side product(s), and is difficult for industrialization either. Japan Patent No. JP1777283 disclosed that cellulose was dissolved in 2.5 mol/L aqueous NaOH solution, but only wood pulp cellulose having a polymerization degree of below 250 and being treated by vapor explosion could be used, which could be dissolved in such aqueous NaOH solution at about 4° C. The cellulose filaments made by using this process have a poor strength and are not suitable for spinning or film-forming in industry.
[0007] The present applicant proposed in Chinese Patent No. 00128162.3 that a mixed aqueous solution of 4 wt %-8 wt % sodium hydroxide and 2 wt %-8 wt % thiourea was used to, after being cooled, directly dissolve at room temperature the natural cellulose having a viscosity average molecular weight of less than 10.1×10 4 and the regenerated cellulose having a viscosity average molecular weight of less than 12×10 4 to obtain transparent cellulose solution. However, the practices indicated that the solvent system must be kept under freezing condition (−20° C.) for 3-8 hours to form an ice-like stuff and then thawed before it was used to dissolve cellulose for preparing transparent concentrated cellulose solution. Thus, it is applicable to laboratory scale only at present, and is not suitable for industrialization.
[0008] In addition, the present applicant proposed in Chinese Patent No. 200310111447.8 that a mixed aqueous solution of 8.1 wt %-12.0 wt % sodium hydroxide and 4.0 wt %-6.0 wt % thiourea was used for directly dissolving cellulose, and a process of using this mixed aqueous NaOH/thiourea solution for preparing regenerated cellulose films or fibers in laboratory scale, but this process was merely provided for research and was not suitable for industrial production.
SUMMARY OF THE INVENTION
[0009] Thus, one object of the present invention is to provide a use of aqueous sodium hydroxide/thiourea solution, wherein sodium hydroxide constitutes 8.1 wt %-12.0 wt % of the total weight of the aqueous solution, and thiourea constitutes 3.0 wt %-6.0 wt % of the total weight of the aqueous solution. Said aqueous solution is used for pilot-scale production of cellulose products, and said cellulose products comprise protein/cellulose, chitin/cellulose, Konjac Glucomannan/cellulose, nano-crystal particle/cellulose and the other composite fibers and/or functional materials.
[0010] According to the use of the present invention, when said sodium hydroxide/thiourea aqueous solution is used for pilot-scale production of cellulose products, the said use comprises the following steps:
(a) Pre-cooling a mixed aqueous solution of sodium hydroxide and thiourea to a first temperature; (b) Placing the pre-cooled, mixed aqueous solution at a second temperature, and then immediately adding a cellulose raw material and dissolving under sufficient agitation to obtain a cellulose solution; (c) Filtering and deaerating said cellulose solution; (d) Using a molding device for pilot-scale production to process the filtered and deaerated cellulose solution to form a cellulose product.
[0015] According to the use of the present invention, between the step (b) and the step (c) is further comprised a step for mixing the cellulose solution with other substances, wherein said other substances comprises proteins, chitins, Konjac Glucomannan, nano-crystal particles, etc.
[0016] According to the use of the present invention, in said aqueous solution of sodium hydroxide/thiourea, the concentration of sodium hydroxide is preferably 9.0 wt %˜10.0 wt %, most preferably 9.5 wt %; and the concentration of thiourea is preferably 4.0 wt % 6.0 wt %, most preferably 4.3 wt %.
[0017] According to the use of the present invention, the said first temperature is −10° C.˜5° C., preferably −8° C.˜0° C., most preferably −6° C.˜1-3° C.
[0018] According to the use of the present invention, the said second temperature is environmental temperature, specifically 0° C.˜25° C., preferably 5° C.˜20° C., most preferably 10° C.
[0019] According to the use of the present invention, the said cellulose raw material can be various cellulose pulps including cotton linter pulp, bagasse pulp, wood pulp, etc., particularly various cellulose pulps having a polymerization degree of below 700 and a relatively narrow distribution of molecular weight, preferably a cellulose pulp having a polymerization degree of 250˜650, most preferably a cellulose pulp having a polymerization degree of 300˜450.
[0020] According to the use of the present invention, after the cellulose raw material is added at said second temperature, the agitation is performed sufficiently for 5 minutes or more, preferably 10 minutes or more, most preferably 15 minutes or more.
[0021] According to the use of the present invention, the concentration of the cellulose solution obtained from the step (b) is 4.0 wt %˜10.0 wt %, preferably 4.5 wt %˜8.0 wt %, more preferably 5.0 wt %˜6.5 wt %. It is preferred that, with the increase of polymerization degree of the cellulose pulp from 250 to 650, the concentration of cellulose solution is decreased from 10 wt % to 4 wt %, and within such a range, the strength of the cellulose filaments can be enhanced by appropriately reducing molecular weight, maintaining narrow distribution of molecular weight and elevating concentration.
[0022] According to the use of the present invention, the said molding device is selected from a variety of molding devices including spinning devices, film-making devices, granulating devices, etc.
[0023] In one embodiment, the aqueous NaOH/thiourea solution is used for spinning by a wet spinning device, and in a preferred embodiment, the aqueous. NaOH/thiourea solution is used for spinning by a two-step coagulation bath spinning device.
[0024] The said two-step coagulation bath spinning device comprises a first coagulation bath and a second coagulation bath. The said first coagulation bath is a mixed aqueous solution of H 2 SO 4 and Na 2 SO 4 , wherein the concentration of H 2 SO 4 is 5 wt %˜20 wt %, preferably 8 wt %˜16 wt %, most preferably 9 wt %˜13 wt %; and the concentration of Na 2 SO 4 is 5 wt %˜25 wt %, preferably 8 wt %˜20 wt %, most preferably 10 wt %˜15 wt %; and the bath temperature is 0˜40° C., preferably 5˜30° C., most preferably 10˜15° C. The said second coagulation bath is 3 wt %˜20 wt %, preferably 5 wt %˜10 wt %, most preferably 5 wt % aqueous solution of H 2 SO 4 , and the bath temperature is 0˜50° C., preferably 10˜30° C., most preferably 10˜20° C.
[0025] The said cellulose solution is jetted from a spinneret into the first coagulation bath for solidification, partial stretch orientation and draft, and then enters into the second coagulation bath for further regeneration and stretch orientation, and is subjected to water washing, plasticizing, drying and winding successively to obtain regenerated cellulose filaments, which may subsequently be used for manufacturing filaments, chopped fibers, nonwovens and the others. The spinneret can be vertical spinneret or horizontal spinneret.
[0026] In another embodiment, the aqueous NaOH/thiourea solution is used for producing regenerated cellulose films through a film-making device.
[0027] In still another embodiment, the aqueous NaOH/thiourea solution is used for granulation through a granulating device, and is used as chromatographic packings, etc.
[0028] According to the use of the present invention, the said cellulose products can be in the form of filaments, chopped fibers, films, chromatographic packings and/or nonwovens, etc.
[0029] The present inventors had confirmed experimentally that the aqueous NaOH/thiourea solution can dissolve chitins, proteins, Konjac Glucomannan and the like which are hardly dissoluble, and can facilitate the uniform dispersion of nano-particles, so that it can be used advantageously for preparing composite fibers and/or functional materials of protein/cellulose, chitin/cellulose, Konjac Glucomannan/cellulose, nano-crystal particle/cellulose, etc.
[0030] Thus, in a further embodiment, aqueous NaOH/thiourea solution is used for preparing functional chitin/cellulose, protein/cellulose, nano-crystal particle/cellulose fibers, and is optionally granulated by a granulating device so as to be used as chromatographic packings and the like.
[0031] As compared to the prior art, the advantages of the present invention lie in that, firstly, the chemical raw materials used are common and less costly, which are made available as a new solvent for cellulose by cooling to a reduced temperature; secondly, a variety of high added-value cellulose products can be produced according to the present invention; thirdly, since CS 2 is not used in the production process, such regenerated cellulose products are free of sulfur as determined (viscose fibers have a sulfur content of 8˜10 g/kg) and are regenerated cellulose materials with very high safety; fourthly, during the production according to the present invention, the production cycle is short (30˜40 hours), which is equivalent to ⅓ that of viscose process; and fifthly, the process of the present invention is particularly suitable for industrial production and practical applications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 shows a schematic diagram of a two-step coagulation bath spinning device according to a preferred embodiment of the present invention.
[0033] FIG. 2 shows a cross-section view of the cellulose filaments obtained according to the present invention.
[0034] FIG. 3 shows the surface of cellulose filaments obtained according to the present invention.
[0035] FIG. 4 shows packages of cellulose filaments obtained according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] The present invention is further illustrated in detail in conjugation with the drawings and specific examples, but the present invention is not intended to be limited thereto.
[0037] In a preferred embodiment of the present invention, a compact device for pilot-scale production ( FIG. 1 ) according to the present invention is used for wet spinning, wherein a cellulose solution is firstly deaerated by a deaerating tank a, and then, after being jetted out through a spinneret b, enters into a first coagulation bath tank c and subsequently, a second coagulation bath tank d in tow, followed by passing through a water-washing device e, and as desired, being plasticized in a plasticizer tank f, and finally is drawn and wound by a winding device g to form a package. Preferably, the spinneret is reformed to spin downwardly (or the length/diameter ratio of the spinneret is increased) so that cellulose molecules are stretched and oriented by gravity even when they are still in solution. Meanwhile, the solidification time of cellulose is further prolonged and the stretch ratio is increased by arrangement of devices and process. Preferably, multi-stage stretch is employed to further enhance the strength of cellulose filaments, so that regenerated cellulose filaments with better mechanical properties are prepared.
Example 1
[0038] 3 kg of a mixed aqueous solution of 9.5 wt % NaOH/4.3 wt % thiourea (analytically pure) was pre-cooled to −4.8° C., then 152 g of dry cotton linter cellulose pulp (having a polymerization degree of 620) was added immediately, while stirring under 720 rpm at room temperature for 15 minutes to dissolve the cellulose completely. A transparent cellulose solution was obtained by deaerating under vacuum at 5° C. for 12 hours. The obtained cellulose solution was pressed to pass through a spinneret and entered into a first coagulation bath for solidification, wherein the bath was a mixed aqueous solution of 15 wt % H 2 SO 4 /10 wt % Na 2 SO 4 and the bath temperature was 10° C. Subsequently, the cellulose filaments entered into a second coagulation bath for regeneration, wherein the bath was an aqueous solution of 5 wt % H 2 SO 4 and the bath temperature was 10° C. The stretched and regenerated cellulose filaments were washed with water and entered into a plasticizer tank for oiling, dried by a drying roll, and then wound on a bobbin to form a spindle numbered as 1. The filaments had a round cross-section ( FIG. 2 ) similar to Lyocell, smooth surface ( FIG. 3 ), soft and glossy appearance ( FIG. 4 ), and were free of sulfur and possessed excellent mechanical properties (Table 1).
Example 2
[0039] 3 kg of a mixed aqueous solution of 9.5 wt % NaOH/4.3 wt % thiourea (analytically pure) was pre-cooled to −4.8° C., and then 178 g of dry cotton linter cellulose pulp (having a polymerization degree of 440) was added immediately, while stirring under 720 rpm at room temperature for 15 minutes to dissolve the cellulose completely. A transparent cellulose solution was obtained by deaerating under vacuum at 5° C. for 5 hours. The obtained cellulose solution was pressed to pass through a spinneret and entered into a first coagulation bath for solidification, wherein the bath was a mixed aqueous solution of 9.0 wt % H 2 SO 4 /11.2 wt % Na 2 SO 4 and the bath temperature was 15° C. Subsequently, the cellulose filaments entered into a second coagulation bath for regeneration, wherein the bath was an aqueous solution of 5 wt % H 2 SO 4 and the bath temperature was 15° C. The stretched and regenerated cellulose filaments were washed with water and entered into a plasticizer tank for oiling, dried by a drying roll, and then wound on a bobbin to form a spindle numbered as 2. The filaments had a round cross-section, soft and glossy appearance, were free of sulfur and possessed excellent mechanical properties (Table 1).
Example 3
[0040] 3 kg of a mixed aqueous solution of 9.5 wt % NaOH/4.3 wt % thiourea (industrially pure) was pre-cooled to −4.6° C., and then 178 g of dry cotton linter cellulose pulp (having a polymerization degree of 440) was added immediately, while stirring under 720 rpm at room temperature for 15 minutes to dissolve the cellulose completely. A transparent cellulose solution was obtained by deaerating under vacuum at 5° C. for 5 hours. The obtained cellulose solution was pressed to pass through a spinneret and entered into a first coagulation bath for solidification, wherein the bath was a mixed aqueous solution of 12.2 wt % H 2 SO 4 /13.6 wt % Na 2 SO 4 and the bath temperature was 12.2° C. Subsequently, the cellulose filaments entered into a second coagulation bath for regeneration, wherein the bath was an aqueous solution of 5 wt % H 2 SO 4 and the bath temperature was 13.6° C. The stretched and regenerated cellulose filaments were washed with water and entered into a plasticizer tank for oiling, dried by a drying roll, and then wound on a bobbin to form a spindle numbered as 3. The filaments had a round cross-section, soft and glossy appearance, were free of sulfur and possessed excellent mechanical properties (Table 1).
[0041] The mechanical properties of the cellulose filaments obtained in the above examples were measured by XQ-1 constant-speed elongation type fiber strength tester. Their breaking strength and elongation at break in dry state were summarized in Table 1.
[0000]
TABLE 1
Test results of mechanical properties -- breaking strength and
elongation at break -- of cellulose filaments
Elon-
Concentration
Polymerization
Grade of
Tensile
gation
of cellulose
degree of
chemical
strength
at break
No.
(wt %)
cellulose
reagents
(cN/dtex)
(%)
1
4.8
620
Analytical
1.4
5
grade
2
5.6
440
Analytical
2.2
2
grade
3
5.6
440
Industrial
2.0
2
grade
Example 4
[0042] 126 g of dry cotton linter cellulose pulp (having a polymerization degree of 620) was added into 3 kg of a mixed aqueous solution of 6 wt % NaOH/5 wt % thiourea (chemically pure), mixed homogenously and frozen (−6° C.˜−10° C.) to form a solid, then thawed and agitated at room temperature until the cellulose was dissolved completely to obtain a solution I (having a cellulose weight concentration of 4%). 25 g of chitin (having a viscosity-average molecular weight of 1.4×10 6 and an acetylation degree of 73%) was immersed in 0.4 L of 46 wt % NaOH solution in ice bath condition for 6 hours, and ice-cakes were gradually added to obtain a chitin solution II having a weight concentration of 2%. The solution I and the solution II were mixed in a ratio (weight ratio) of 2:1 under stirring to obtain a spinning solution, which was deaerated by standing under vacuum at 5° C. for 12 hours to form a transparent solution. This concentrated cellulose-chitin solution was pressed to pass through a spinneret, and entered into a first coagulation bath for solidification, wherein the bath was a mixed aqueous solution of 15 wt % H 2 SO 4 /10 wt % Na 2 SO 4 and the bath temperature was 10° C. Subsequently, the cellulose filaments entered into a second coagulation bath for regeneration, wherein the bath was an aqueous solution of 5 wt % H 2 SO 4 and the bath temperature was 10° C. The stretched and regenerated cellulose filaments were washed with water and entered into a plasticizer tank for oiling, dried by a drying roll, and then wound on a bobbin to form a spindle numbered as 4. The chitin/cellulose filaments were free of sulfur, and had a round cross-section, a soft and glossy appearance, and relatively high absorption capacity for metal ions.
Example 5
[0043] 126 g of dry cotton linter cellulose pulp (having a polymerization degree of 620) was added into 3 kg of a mixed aqueous solution of 6 wt % NaOH/5 wt % thiourea (chemically pure), mixed homogenously and frozen (−6° C.) to form a solid, then thawed and agitated at room temperature until the cellulose was dissolved completely to obtain a solution I (having a cellulose weight concentration of 4%). 100 g of soybean protein isolate (SPI) was dissolved at room temperature into 900 g of a mixed aqueous solution of 6 wt % NaOH/5 wt % thiourea (chemically pure) to obtain a solution II (having a SPI weight concentration of 10%). The solution I and the solution II were mixed in a cellulose/SPI weight ratio of 9:1 at room temperature and stirred for 0.5 hours, and then deaerated by standing under vacuum at 5° C. for 5 hours to obtain a spinning solution. This mixed cellulose-soybean protein solution was pressed to pass through a spinneret, and entered into a first coagulation bath for solidification, wherein the bath was a mixed aqueous solution of 9.0 wt % H 2 SO 4 /11.2 wt % Na 2 SO 4 and the bath temperature was 15° C. Subsequently, the cellulose filaments entered into a second coagulation bath for regeneration, wherein the bath was an aqueous solution of 5 wt % H 2 SO 4 and the bath temperature was 15° C. The stretched and regenerated cellulose filaments were washed with water and entered into a plasticizer tank for oiling, dried by a drying roll, and then wound on a bobbin to form a spindle numbered as 5. The soybean protein/cellulose filaments were free of sulfur, and possessed biocompatibility and a function of promoting cell growth.
Example 6
[0044] 3 kg of a mixed aqueous solution of 9.5 wt % NaOH/4.3 wt % thiourea (industrially pure) was pre-cooled to −6° C., and then 178 g of dry cotton linter cellulose pulp (having a polymerization degree of 440) was added immediately, while stirring under 720 rpm at room temperature for 15 minutes to dissolve cellulose completely. 18 g of tourmaline nano-crystals were dispersed in 120 g of a mixed aqueous solution of 9.5 wt % NaOH/4.3 wt % thiourea (industrially pure) and agitated for 8 hours to form a suspension of tourmaline. The pre-dispersed tourmaline suspension was added dropwise into a round bottom flask charged with the cellulose solution, and then the system was closed and agitated vigorously at 0° C. in ice-water bath under ultrasonic environment to obtain a uniformly mixed liquid. A transparent cellulose solution was obtained by deaerating under vacuum at 5° C. for 5 hours. The obtained cellulose solution was pressed to pass through a spinneret, and entered into a first coagulation bath for solidification, wherein the bath was an aqueous solution of 5 wt % CaCl 2 and the bath temperature was 20° C. Subsequently, the cellulose filaments entered into a second coagulation bath for regeneration, wherein the bath was an aqueous solution of 3 wt % hydrochloric acid and the bath temperature was 20° C. The stretched and regenerated cellulose filaments were washed with water and entered into a plasticizer tank for oiling, dried by a drying roll, and then wound on a bobbin to form a spindle numbered as 6. The nano-crystal/cellulose filaments were free of sulfur and had significant effects against staphylococcus aureus.
[0045] It should be understood that all value ranges in the description and claims are intended to include their end values and all subranges within these ranges.
[0046] Although the present invention is illustrated and described with reference to the illustrative examples, those skilled in the art would understand that the present invention could be varied in manners and details without departing from the spirit and scope of the present invention. The protection scope of the present invention is defined as claimed in the appended claims.
|
The present invention relates to the use of an aqueous sodium hydroxide/thiourea solution, specifically to the use of an aqueous sodium hydroxide/thiourea solution for pilot-scale production of cellulose products, wherein sodium hydroxide constitutes 8.1%-12.0% of the total weight of the aqueous solution, thiourea constitutes 3.0%-6.0% of the total weight of the aqueous solution, and said cellulose products include regenerated cellulose filaments, films, nonwovens, as well as composite fibers and/or functional materials of protein/cellulose, chitin/cellulose, Konjac Glucomannan/cellulose, nano-crystal particle/cellulose, etc.
| 2
|
GOVERNMENT FUNDING
[0001] The invention described herein was made with government support under Grant Number DA018151-A2 awarded by the National Institute on Drug Abuse.
[0002] The United States Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] The opium poppy, Papaver somniferum, has been used for centuries for the relief of pain and to induce sleep (Casy, A. F.; Parfitt, R. T. Opioid analgesics: chemistry and receptors; Plenum Press: New York, 1986; xv, 518). Among the most important constituents in opium are the alkaloids morphine and codeine. Many of the agonists and antagonists derived from these alkaloids are essential for the practice of modern medicine. While many potent agonists are effective analgesics, they have undesirable side effects, such as tolerance, dependence, and respiratory depression. (Stein, C.; Schafer, M.; Machelska, H. Nat. Med. 2003, 9, 1003-1008).
[0004] Endogenous opioid peptides are known and are involved in the mediation or modulation of a variety of mammalian physiological processes, many of which are mimicked by opiates or other non-endogenous opioid ligands. Some of the processes that have been suggested include analgesia, tolerance and dependence, appetite, renal function, gastrointestinal motility, gastric secretion, respiratory depression, learning and memory, mental illness, epileptic seizures and other neurological disorders and cardiovascular responses.
[0005] Intensive research of the last two decades has given us a better understanding of opioid receptor structure, distribution, and pharmacology (Waldhoer, M.; Bartlett, S. E.; Whistler, J. L. Annu. Rev. Biochem. 2004, 73, 953-990). Three types of opioid receptors known as mu (μ), delta, (δ), and kappa (κ) and receptor subtypes have been identified, and the mRNA encoding these receptors has been isolated. There is substantial pharmacological evidence for subtypes of each (Reisine, T. Neurotransmitter Receptors V: Opiate Receptors. Neuropharmacology 1995, 34, 463-472). It has become clear that each receptor mediates unique pharmacological responses and is differentially distributed in the central nervous system (Goldstein, A.; Naidu, A., Mol. Pharmacol. 1989, 36, 265-272; and Mansour, A.; Fox, C. A.; Akil, H.; Watson, S. J., Trends Neurosci. 1995, 18, 22-29).
[0006] The endogenous ligands for the opioid receptors are neuropeptides (Casy, A. F.; Parfitt, R. T. Opioid analgesics: chemistry and receptors; Plenum Press: New York, 1986; xv, 518). To date, three families of endogenous opioid peptides have been identified. They are classified, β-endorphins, enkephalins, and dynorphins (Gutstein, H.; Akil, H. Opioid Analgesics. Goodman & Gilman's The Pharmacological Basis of Therapeutics; 10th ed.; McGraw-Hill: New York, 2001; pp 569-619; and Eguchi, M., Med. Res. Rev. 2004, 24, 182-212). Although most of these endogenous opioids have little selectivity for opioid receptors, it is generally accepted that (3-endorphins, enkephalins, and dynorphins display greater affinity for μ, δ and κ receptors respectively.
[0007] There are several structural classes of nonpeptidic opioid receptor ligands (Eguchi, M., Med. Res. Rev. 2004, 24, 182-212; Kaczor, A.; Matosiuk, D., Curr. Med. Chem. 2002, 9, 1567-1589; and Kaczor, A.; Matosiuk, D., Curr. Med. Chem., 2002, 9, 1591-1603). The oldest class of compounds are those derived from morphine. Examples of other structural classes include fentanyl, cyclazocine, SNC 80, U50,488H, and 3FLB. The common structural motif in all of these ligands is the presence of a basic amino group.
[0008] Currently, there is a need for new opioid receptor ligands that have fewer side effects than known ligands. Such ligands would be useful for the treatment of diseases and conditions associated with the activity of opioid receptors. Such ligands would also be useful as pharmacological tools for the further study of opioid pharmacology.
SUMMARY OF THE INVENTION
[0009] The present invention provides compounds that act as opioid receptor ligands. Accordingly there is provided a compound of the invention which is a compound of formula I:
[0000]
[0000] wherein:
[0010] R 1 is H, halo, azido, hydroxy, oxo (═O), (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkylthio, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkoxy, aryl, heteroaryl, aryloxy, heteroaryloxy, aryl(C 1 -C 6 )alkyl, aryl(C 1 -C 6 )alkoxy, heteroaryl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkoxy, Het, Het(C 1 -C 6 )alkyl, Het(C 1 -C 6 )alkoxy, formyloxy, acetoxy, R c C(═O)O—, R b C(═S)O—, R b C(═O)S—, (R g ) 3 SiO—, R d R e NC(═O)O—, (R h ) 3 CC(═NR d )O—, R m R n N—, or R b S(═O) 2 O—;
[0011] R 2 is H, hydroxymethyl, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxymethyl, carboxy, (C 1 -C 6 )alkoxycarbonyl or R d R e NC(═O)—;
[0012] R 3 is H or (C 1 -C 6 )alkyl;
[0013] R 4 is H or (C 1 -C 6 )alkyl;
[0014] R 5 is H or (C 1 -C 6 )alkyl;
[0015] R 6 is (C 1 -C 6 )alkyl, (C 1 -C 6 )cycloalkyl, aryl, Het, carboxy, R j R k NC(═O)—or heteroaryl;
[0016] X is —O—, —S—, or —NR a —;
[0017] each R a is independently H, (C 1 -C 6 )alkyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0018] each R b is independently H, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, Het, Het(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0019] each R c is independently H, (C 2 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkoxycarbonyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, Het, Het(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0020] each R d and R e is independently H, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkenyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0021] each R g is independently (C 1 -C 6 )alkyl;
[0022] each R h is independently H, (C 1 -C 6 )alkyl, fluoro, or chloro;
[0023] each R j ; and R k is independently H, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkenyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, Het, Het(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0024] each R m and R n is independently H, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkenyl, aryl, heteroaryl, aryloxy, heteroaryloxy, aryl(C 1 -C 6 )alkyl, aryl(C 1 -C 6 )alkoxy, heteroaryl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkoxy, Het, Het(C 1 -C 6 )alkyl, Het(C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, R p C(═O)—, R d R e NC(═O)—, (R h ) 3 C(═NR d )—, or R b S(═O) 2 —; and
[0025] each R p is independently H, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, Het, Het(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0026] wherein any aryl or heteroaryl of R 1 , R 6 , and R a -R e , and R p is optionally substituted with one or more (e.g. 1, 2, 3, or 4) halo, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, (C 1 -C 6 )alkoxycarbonyl, cyano, nitro, trifluomethyl, trifluoromethoxy, R t S(═O) 2 —, or R u R v N;
[0027] each R t is independently H, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, Het, Het(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl;
[0028] wherein any aryl or heteroaryl of R t is optionally substituted with one or more (e.g. 1, 2, 3, or 4) halo, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, (C 1 -C 6 )alkoxycarbonyl, cyano, nitro, trifluomethyl, trifluoromethoxy, or R u R v N;
[0029] wherein any Het of R 1 , R 6 , R b , R c , and R j -R p is optionally substituted with one or more halo, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, (C 1 -C 6 )alkoxycarbonyl, cyano, nitro, trifluomethyl, trifluoromethoxy, oxo (═O), thioxo (═O—S), R q S(═O) 2 O—, aryl, heteroaryl, or R u R v N;
[0030] each R q is independently H, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, aryl, heteroaryl, aryl(C 1 -C 6 )alkyl, Het, Het(C 1 -C 6 )alkyl, or heteroaryl(C 1 -C 6 )alkyl; and
[0031] each R u and R v is independently H or (C 1 -C 6 )alkyl;
[0032] or a salt thereof.
[0033] The invention also provides a pharmaceutical composition comprising a compound of formula I; or a pharmaceutically acceptable salt thereof; and a pharmaceutically acceptable diluent or carrier.
[0034] The invention also provides a method for modulating the activity of an opioid receptor comprising contacting the receptor (in vitro or in vivo) with an effective modulatory amount of a compound of formula I or a salt thereof.
[0035] The invention also provides a therapeutic method for treating a disease or condition in a mammal wherein modulation of the action of an opioid receptor is desired (e.g. pain, drug addiction, alcohol addiction, drug abuse, alcohol abuse, opioid-induced constipation, irritable bowel syndrome, nausea, vomiting, pruritic dermatoses, depression, smoking addiction, sexual dysfunction, stroke, obesity, diabetes, trauma, eating disorders, opioid overdose, shock, spinal damage, diarrheic syndromes, bowel motility disorders including post-operative ileus and constipation, visceral pain including post-operative pain, and inflammatory bowel disorders) comprising administering to the mammal, an effective amount of a compound of formula I; or a pharmaceutically acceptable salt thereof.
[0036] The invention also provides a compound of formula I or a pharmaceutically acceptable salt thereof for use in medical therapy.
[0037] The invention also provides the use of a compound of formula I or a pharmaceutically acceptable salt thereof to prepare a medicament useful for the treatment of a disease or condition in a mammal wherein modulation of the action of an opioid receptor is desired.
[0038] The invention also provides a method for binding a compound of formula I or a pharmaceutically acceptable salt thereof to mammalian tissue comprising opioid receptors, in vivo or in vitro, comprising contacting the tissue with an amount of a compound of formula I or a pharmaceutically acceptable salt thereof effective to bind to said receptors. Tissue comprising a compound of formula I or a pharmaceutically acceptable salt thereof bound to opioid receptor sites can be used to measure the selectivity of test compounds for specific receptor subtypes, or can be used as a tool to identify potential therapeutic agents for the treatment of diseases or conditions associated with opioid receptor activity, by contacting said agents with said ligand-receptor complexes, and measuring the extent of displacement of the ligand and/or binding of the agent.
[0039] The invention also provides a detectably labeled (e.g. a radiolabeled) compound comprising a compound of formula I; or a salt thereof, that comprises or is linked to one or more detectable groups.
[0040] The invention also provides synthetic processes and synthetic intermediates disclosed herein. Certain compounds of formula (I) are useful as intermediates for preparing other compounds of formula (I).
[0041] The invention also provides the compounds prepared in the Examples herein, as well as methods for modulating opioid receptor activity with such compounds.
DETAILED DESCRIPTION
[0042] The following definitions are used, unless otherwise described. Halo is fluoro, chloro, bromo, or iodo. Alkyl, alkoxy, etc. denote both straight and branched groups; but reference to an individual radical such as propyl embraces only the straight chain radical, a branched chain isomer such as isopropyl being specifically referred to.
[0043] Aryl denotes a phenyl radical or an ortho-fused bicyclic carbocyclic radical having about nine to ten ring atoms in which at least one ring is aromatic.
[0044] Heteroaryl encompasses a radical attached via a ring carbon of a monocyclic aromatic ring containing five or six ring atoms consisting of carbon and one to four heteroatoms each selected from the group consisting of non-peroxide oxygen, sulfur, and N(Y) wherein Y is absent or is H, O, (C 1 -C 4 )alkyl, phenyl or benzyl, as well as a radical of an ortho-fused bicyclic heterocycle of about eight to ten ring atoms derived there from, particularly a benz-derivative or one derived by fusing a propylene, trimethylene, or tetramethylene diradical thereto.
[0045] “Het” includes a mono or bicyclic saturated or partially unsaturated ring system comprising about 4 to about 12 atoms selected from carbon, O, S, and N. Examples of “Het” include dihydrofuran, tetrahydrofuran, pyrazoline, piperidine, morpholine, thiomorpholine, piperazine, indoline, isoindoline, pyrazolidine, imidazoline, imidazolidine, pyrroline, pyrrolidine, chroman, and isochroman.
[0046] It will be appreciated by those skilled in the art that compounds of the invention having a chiral center may exist in and be isolated in optically active and racemic forms. Some compounds may exhibit polymorphism. It is to be understood that the present invention encompasses any racemic, optically-active, polymorphic, or stereoisomeric form, or mixtures thereof, of a compound of the invention, which possess the useful properties described herein, it being well known in the art how to prepare optically active forms (for example, by resolution of the racemic form by recrystallization techniques, by synthesis from optically-active starting materials, by chiral synthesis, or by chromatographic separation using a chiral stationary phase) and how to determine opioid receptor binding and modulatory activity using the standard tests described herein, or using other similar tests which are well known in the art.
[0047] Specific values listed below for radicals, substituents, and ranges, are for illustration only; they do not exclude other defined values or other values within defined ranges for the radicals and substituents.
[0048] Specifically, (C 1 -C 6 )alkyl can be methyl, ethyl, propyl, isopropyl, butyl, iso-butyl, sec-butyl, pentyl, 3-pentyl, or hexyl; (C 3 -C 6 )cycloalkyl can be cyclopropyl, cyclobutyl, cyclopentyl, or cyclohexyl; (C 1 -C 6 )alkoxy can be methoxy, ethoxy, propoxy, isopropoxy, butoxy, iso-butoxy, sec-butoxy, pentoxy, 3-pentoxy, or hexyloxy; (C 1 -C 6 )alkanoyl can be acetyl, propanoyl or butanoyl; (C 1 -C 6 )alkoxycarbonyl can be methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, pentoxycarbonyl, or hexyloxycarbonyl; (C 2 -C 6 )alkanoyloxy can be acetoxy, propanoyloxy, butanoyloxy, isobutanoyloxy, pentanoyloxy, or hexanoyloxy; aryl can be phenyl, indenyl, or naphthyl; and heteroaryl can be furyl, imidazolyl, triazolyl, triazinyl, oxazoyl, isoxazoyl, thiazolyl, isothiazoyl, pyrazolyl, pyrrolyl, pyrazinyl, tetrazolyl, pyridyl, (or its N-oxide), thienyl, pyrimidinyl (or its N-oxide), indolyl, isoquinolyl (or its N-oxide) or quinolyl (or its N-oxide).
[0049] A specific value for R 1 is H, halo, azido, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkylthio, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkoxy, aryl, heteroaryl, aryloxy, heteroaryloxy, aryl(C 1 -C 6 )alkyl, aryl(C 1 -C 6 )alkoxy, heteroaryl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkoxy, Het, Het(C 1 -C 6 )alkyl, Het(C 1 -C 6 )alkoxy, formyloxy, acetoxy, R c C(═O)O—, R b C(═S)O—, R b C(═O)S—, (R g ) 3 SiO—, R d R e NC(═O)O—, (R h ) 3 C(═NR d )O—, R m R n N—, or R b S(═O) 2 O—;
[0050] A specific value for R 1 is H, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, aryl, heteroaryl, aryloxy, heteroaryloxy, aryl(C 1 -C 6 )alkyl, aryl(C 1 -C 6 )alkoxy, heteroaryl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkoxy, formyloxy, R c C(═O)O—, (R g ) 3 SiO—, R d R e NC(═O)O—, (R h ) 3 C(═NR d )O—, or R b S(═O) 2 O—.
[0051] A specific value for R 1 is hydroxy, (C 1 -C 6 )alkoxy, aryloxy, heteroaryloxy, aryl(C 1 -C 6 )alkoxy, heteroaryl(C 1 -C 6 )alkoxy, formyloxy, acetoxy, R c C(═O)O—, or R b S(═O) 2 O—.
[0052] A specific value for R 1 is formyloxy, acetoxy, R c C(═O)O—, or R b S(═O) 2 O—.
[0053] A specific value for R 1 is acetoxy, propanoyloxy, isobutanoyloxy, methacryloyloxy, methoxyoxalyloxy, benzoyloxy, trimethylsilyloxy, imidazole-1-ylthiocarbonyloxy, methoxymethoxy, aminocarbonyloxy, butanoyloxy, pentanoyloxy, 1-bromobenzoyloxy, 2-bromobenzoyloxy, 3-bromobenzoyloxy, 4-methoxybenzoyloxy, 4-nitrobenzoyloxy, phenylsulfonyloxy, 4-methylphenylsulfonyloxy, 4-methoxyphenylsulfonyloxy, 4-bromophenylsulfonyloxy, (3-pyridylcarbonyloxy, methylsulfonyloxy, hydroxy, 1-imino-2,2,2-trichloroethoxy, phenylaminocarbonyloxy, allylaminocarbonyloxy, 3,4-dichlorobenzoyloxy, bromo, azido, amino, acetylamino, phenylcarbonylamino, methylsulfonylamino, phenylsulfonylamino, or benzoyloxy.
[0054] A specific value for R 1 is propanoyloxy, isobutanoyloxy, methacryloyloxy, methoxyoxalyloxy, 3-pyridylcarbonyloxy, methylsulfonyloxy, hydroxy, 1-imino-2,2,2-trichloroethoxy, phenylaminocarbonyloxy, allylaminocarbonyloxy, or benzoyloxy.
[0055] A specific value for R 1 is acetoxy, propanoyloxy, methylsulfonyloxy, or benzoyloxy.
[0056] A specific value for R 1 is benzoyloxy, 3-pyridylcarbonyloxy, or phenylaminocarbonyloxy.
[0057] A specific value for R 2 is hydroxymethyl, (C 1 -C 6 )alkoxymethyl, carboxy, (C 1 -C 6 )alkoxycarbonyl, or R d R e NC(═O)—.
[0058] A specific value for R 2 is carboxy, (C 1 -C 6 )alkoxycarbonyl; or R d R e NC(═O)—.
[0059] A specific value for R 2 is methoxycarbonyl.
[0060] A specific value for R 4 is H or methyl.
[0061] A specific value for R 3 is methyl.
[0062] A specific value for R 4 is methyl.
[0063] A specific value for R 5 is H.
[0064] A specific value for R 5 is methyl.
[0065] A specific value for R 5 is H.
[0066] A specific value for R 6 is aryl or heteroaryl, optionally substituted with one or more (e.g. 1, 2, 3, or 4) halo, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, (C 1 -C 6 )alkoxycarbonyl, cyano, nitro, trifluomethyl, trifluoromethoxy, or R e R f N.
[0067] A specific value for R 6 is phenyl, thienyl, furanyl, pyrrolyl, or pyridyl, optionally substituted with one or more (e.g. 1, 2, 3, or 4) halo, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, (C 1 -C 6 )alkoxycarbonyl, cyano, nitro, trifluomethyl, trifluoromethoxy, or R e R f N.
[0068] A specific value for R 6 is phenyl, or Het, optionally substituted with one or more (e.g. 1, 2, 3, or 4) halo, hydroxy, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkanoyloxy, (C 1 -C 6 )alkoxycarbonyl, cyano, nitro, trifluomethyl, trifluoromethoxy, or R e R f N.
[0069] A specific value for R 6 is 3-furyl, 3,4-dihydroxy-2,5-dimethoxytetrahydrofuran-3-yl, 2,5-dihydro-2,5-dimethoxyfuran-3-yl, carboxy, 2,5-dihydro-5-bromo-2-oxofuran-3-yl, 2-bromofuran-3-yl, 2,5-dimethoxytetrahydrofuran-3-yl, 1-methylsulfonylpyrrol-3-yl, 1-phenylsulfonylpyrrol-3-yl, 1-(4-methoxyphenyl)sulfonylpyrrol-3-yl, 1-(4-nitrophenyl)sulfonylpyrrol-3-yl, 3-pyrrolyl, 4-methoxycarbonylthiazol-2-yl, 4-methocycarbonyloxazol-2-yl, thiazol-2-yl, or oxazol-2-yl.
[0070] A specific value for R 6 is 3-furyl.
[0071] A specific value for X is —O—.
[0072] A specific value for R a is H, methyl, ethyl, phenyl, thienyl, furanyl, pyrrolyl, pyridyl, benzyl, phenethyl, thienylmethyl, furanylmethyl, pyrrolylmethyl, or pyridylmethyl.
[0073] A specific value for R b is H, methyl, ethyl, phenyl, thienyl, furanyl, pyrrolyl, pyridyl, benzyl, phenethyl, thienylmethyl, furanylmethyl, pyrrolylmethyl, or pyridylmethyl.
[0074] A specific value for R c is H, ethyl, phenyl, thienyl, furanyl, pyrrolyl, pyridyl, benzyl, phenethyl, thienylmethyl, furanylmethyl, pyrrolylmethyl, or pyridylmethyl.
[0075] A specific value for R d and R e is independently H, methyl, ethyl, phenyl, thienyl, furanyl, pyrrolyl, pyridyl, benzyl, phenethyl, thienylmethyl, furanylmethyl, pyrrolylmethyl, or pyridylmethyl.
[0076] A specific compound of formula (I) is a compound of formula (II):
[0000]
[0000] wherein R 1 -R 6 have any of the values or specific values defined herein; or a salt thereof.
[0077] Specific compounds of the invention also include compounds of formula I that comprise or that are linked to one or more detectable groups or isotopes. Such detectable compounds may be used as imaging agents or as probes for evaluating opioid receptor structure and function. For example, one or more detectable groups can be incorporated into the core of the compound, or can be attached to the compound directly, through a linking group, or through a chelating group. Suitable detectable groups include deuterium, tritium, iodine-125, iodine-131, iodine-123, astatine-210, carbon-11, carbon-14, nitrogen-13, or fluorine-18. Additionally, groups such as Tc-99m and Re-186 can be attached to a linking group or bound by a chelating group which is then attached to the compound of formula I directly or by means of a linker. Suitable radiolabeling techniques are routinely used in radiopharmaceutical chemistry.
[0078] In one embodiment the invention also provides a compound of formula V:
[0000]
[0000] wherein R 2 -R 6 and X have any of the values or specific values described herein. Compounds of formula V (e.g. Compound 8) are useful as intermediates for preparing salvinorin analogs.
[0079] In cases where compounds are sufficiently basic or acidic, a salt of a compound of formula I can be useful as an intermediate for isolating or purifying a compound of formula I. Additionally, administration of a compound of formula I as a pharmaceutically acceptable acid or base salt may be appropriate. Examples of pharmaceutically acceptable salts are organic acid addition salts formed with acids which form a physiological acceptable anion, for example, tosylate, methanesulfonate, acetate, citrate, malonate, tartarate, succinate, benzoate, ascorbate, α-ketoglutarate, and α-glycerophosphate. Suitable inorganic salts may also be formed, including hydrochloride, sulfate, nitrate, bicarbonate, and carbonate salts.
[0080] Pharmaceutically acceptable salts may be obtained using standard procedures well known in the art, for example by reacting a sufficiently basic compound such as an amine with a suitable acid affording a physiologically acceptable anion. Alkali metal (for example, sodium, potassium or lithium) or alkaline earth metal (for example calcium) salts of carboxylic acids can also be made.
[0081] The compounds of formula I can be formulated as pharmaceutical compositions and administered to a mammalian host, such as a human patient in a variety of forms adapted to the chosen route of administration, i.e., orally or parenterally, by intravenous, intramuscular, topical or subcutaneous routes. For example, the compounds can be formulated for administration as a metered aerosol or liquid spray, as drops, in ampoules, in an autoinjector device or as suppositories; for oral parenteral, intranasal, sublingual or rectal administration, or for administration by inhalation or insufflation.
[0082] The compositions may be presented in a form suitable for once-weekly or once-monthly administration; for example, an insoluble salt of the active compound, may be adapted to provide a depot preparation for intramuscular injection. Furthermore, compounds of the invention can be administered in intranasal form via topical use of suitable intranasal vehicles, or via transdermal skin patches well known to those of ordinary skill in that art. To be administered in the form of a transdermal delivery system, the dosage administration will typically be continuous rather than intermittent throughout the dosage regimen.
[0083] The compounds of the present invention can also be administered in the form of liposome delivery systems, such as small unilamellar vesicles, large unilamellar vesicles, and multilamellar vesicles. Liposomes can be formed from a variety of phospholipids, such as cholesterol, stearylamine or phophatidylcholines.
[0084] Thus, the present compounds may be systemically administered, e.g., orally, in combination with a pharmaceutically acceptable vehicle such as an inert diluent or an assimilable edible carrier. They may be enclosed in hard or soft shell gelatin capsules, may be compressed into tablets, or may be incorporated directly with the food of the patient's diet. For oral therapeutic administration, the active compound may be combined with one or more excipients and used in the form of ingestible tablets, buccal tablets, troches, capsules, elixirs, suspensions, syrups, wafers, and the like. Such compositions and preparations should contain at least 0.1% of active compound. The percentage of the compositions and preparations may, of course, be varied and may conveniently be between about 2 to about 60% of the weight of a given unit dosage form. The amount of active compound in such therapeutically useful compositions is such that an effective dosage level will be obtained.
[0085] The tablets, troches, pills, capsules, and the like may also contain the following: binders such as gum tragacanth, acacia, corn starch or gelatin; excipients such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid and the like; a lubricant such as magnesium stearate; and a sweetening agent such as sucrose, fructose, lactose or aspartame or a flavoring agent such as peppermint, oil of wintergreen, or cherry flavoring may be added. When the unit dosage form is a capsule, it may contain, in addition to materials of the above type, a liquid carrier, such as a vegetable oil or a polyethylene glycol. Various other materials may be present as coatings or to otherwise modify the physical form of the solid unit dosage form. For instance, tablets, pills, or capsules may be coated with gelatin, wax, shellac or sugar and the like. A syrup or elixir may contain the active compound, sucrose or fructose as a sweetening agent, methyl and propylparabens as preservatives, a dye and flavoring such as cherry or orange flavor. Of course, any material used in preparing any unit dosage form should be pharmaceutically acceptable and substantially non-toxic in the amounts employed. In addition, the active compound may be incorporated into sustained-release preparations and devices.
[0086] The active compound may also be administered intravenously or intraperitoneally by infusion or injection. Solutions of the active compound or its salts can be prepared in water, optionally mixed with a nontoxic surfactant. Dispersions can also be prepared in glycerol, liquid polyethylene glycols, triacetin, and mixtures thereof and in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms.
[0087] The pharmaceutical dosage forms suitable for injection or infusion can include sterile aqueous solutions or dispersions or sterile powders comprising the active ingredient which are adapted for the extemporaneous preparation of sterile injectable or infusible solutions or dispersions, optionally encapsulated in liposomes. In all cases, the ultimate dosage form should be sterile, fluid and stable under the conditions of manufacture and storage. The liquid carrier or vehicle can be a solvent or liquid dispersion medium comprising, for example, water, ethanol, a polyol (for example, glycerol, propylene glycol, liquid polyethylene glycols, and the like), vegetable oils, nontoxic glyceryl esters, and suitable mixtures thereof. The proper fluidity can be maintained, for example, by the formation of liposomes, by the maintenance of the required particle size in the case of dispersions or by the use of surfactants. The prevention of the action of microorganisms can be brought about by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thimerosal, and the like. In many cases, it will be useful to include isotonic agents, for example, sugars, buffers or sodium chloride. Prolonged absorption of the injectable compositions can be brought about by the use in the compositions of agents delaying absorption, for example, aluminum monostearate and gelatin.
[0088] Sterile injectable solutions can be prepared by incorporating the active compound in the required amount in the appropriate solvent with various of the other ingredients enumerated above, as required, followed by filter sterilization. In the case of sterile powders for the preparation of sterile injectable solutions, the useful methods of preparation include vacuum drying and the freeze drying techniques, which yield a powder of the active ingredient plus any additional desired ingredient present in the previously sterile-filtered solutions.
[0089] For topical administration, the present compounds may be applied in pure form, i.e., when they are liquids. However, it will generally be desirable to administer them to the skin as compositions or formulations, in combination with a dermatologically acceptable carrier, which may be a solid or a liquid.
[0090] Useful solid carriers include finely divided solids such as talc, clay, microcrystalline cellulose, silica, alumina and the like. Useful liquid carriers include water, alcohols or glycols or water-alcohol/glycol blends, in which the present compounds can be dissolved or dispersed at effective levels, optionally with the aid of non-toxic surfactants. Adjuvants such as fragrances and additional antimicrobial agents can be added to optimize the properties for a given use. The resultant liquid compositions can be applied from absorbent pads, used to impregnate bandages and other dressings, or sprayed onto the affected area using pump-type or aerosol sprayers.
[0091] Thickeners such as synthetic polymers, fatty acids, fatty acid salts and esters, fatty alcohols, modified celluloses or modified mineral materials can also be employed with liquid carriers to form spreadable pastes, gels, ointments, soaps, and the like, for application directly to the skin of the user.
[0092] Examples of useful dermatological compositions which can be used to deliver the compounds of formula Ito the skin are known to the art; for example, see Jacquet et al. (U.S. Pat. No. 4,608,392), Geria (U.S. Pat. No. 4,992,478), Smith et al. (U.S. Pat. No. 4,559,157) and Wortzman (U.S. Pat. No. 4,820,508).
[0093] Useful dosages of the compounds of formula I can be determined by comparing their in vitro activity, and in vivo activity in animal models. Methods for the extrapolation of effective dosages in mice, and other animals, to humans are known to the art; for example, see U.S. Pat. No. 4,938,949.
[0094] The amount of the compound, or an active salt or derivative thereof, required for use in treatment will vary not only with the particular salt selected but also with the route of administration, the nature of the condition being treated and the age and condition of the patient and will be ultimately at the discretion of the attendant physician or clinician.
[0095] The compound can be administered in unit dosage form; for example, containing 5 to 1000 mg, 10 to 750 mg, or 50 to 500 mg of active ingredient per unit dosage form.
[0096] Ideally, the active ingredient should be administered to achieve peak plasma concentrations of the active compound of from about 0.5 to about 75 μM, about 1 to 50 μM, or about 2 to about 30 μM. This may be achieved, for example, by the intravenous injection of a 0.05 to 5% solution of the active ingredient, optionally in saline, or orally administered as a bolus containing about 1-100 mg of the active ingredient. Desirable blood levels may be maintained by continuous infusion to provide about 0.01-5.0 mg/kg/hr or by intermittent infusions containing about 0.4-15 mg/kg of the active ingredient(s).
[0097] The desired dose may conveniently be presented in a single dose or as divided doses administered at appropriate intervals, for example, as two, three, four or more sub-doses per day. The sub-dose itself may be further divided, e.g., into a number of discrete loosely spaced administrations; such as multiple inhalations from an insufflator or by application of a plurality of drops into the eye.
[0098] Processes for preparing compounds of formula I are provided as further embodiments of the invention and are illustrated by the following procedures in which the meanings of the generic radicals are as given above unless otherwise qualified.
[0099] A compound of formula I can generally be prepared by as illustrated in the following Scheme I.
[0000]
[0100] Compounds of the invention can also be administered in combination with other therapeutic agents, for example, other agents that are useful for the modulation of opioid activity. Examples of such agents include morphine, codeine, fentanyl, hydromorphone, naloxone, naltrexone, and nalmefene. Accordingly, in one embodiment, the invention also provides a composition comprising a compound of formula I, or a pharmaceutically acceptable salt thereof, at least one other therapeutic agent, and a pharmaceutically acceptable diluent or carrier. The invention also provides a kit comprising a compound of formula I, or a pharmaceutically acceptable salt thereof, at least one other therapeutic agent, packaging material, and instructions for administering the compound of formula I or the pharmaceutically acceptable salt thereof and the other therapeutic agent or agents to an animal to modulate opioid receptor activity.
[0101] The ability of a compound of the invention to act as a modulator of opioid receptor activity can be determined using pharmacological models which are well known to the art. For example, representative compounds of the invention were evaluated as described by Harding W W, et al., J. Nat. Prod. 2006, 69:107-112; and they were found to have opioid antagonist activity. Accordingly compounds of the invention may be useful as therapeutic agents for the treatment of diseases wherein the modulation of opioid activity is indicated. Such diseases include but are not limited to, pain, drug addiction, alcohol addiction, drug abuse, alcohol abuse, opioid-induced constipation, irritable bowel syndrome, nausea, vomiting, pruritic dermatoses, depression, smoking addiction, sexual dysfunction, stroke, obesity, diabetes, trauma, eating disorders, opioid overdose, shock, spinal damage, diarrheic syndromes, bowel motility disorders including post-operative ileus and constipation, visceral pain including post-operative pain, and inflammatory bowel disorders. Additionally, compounds of the invention may be useful as pharmacological tools for the further investigation of opioid receptor function.
[0102] The invention will now be illustrated by the following non-limiting Examples.
[0103] Unless otherwise indicated, all reagents were purchased from commercial suppliers and were used without further purification. All melting points were determined on a Thomas—Hoover capillary melting apparatus and are uncorrected. The 1 H NMR and 13 C NMR spectra were recorded at 300 MHz on a Bruker Avance-300 spectrometer or on a Bruker AMX-600 spectrometer using CDCl 3 as solvent, δ values in ppm (TMS as internal standard), and J(Hz) assignments of 1 H resonance coupling. HMBC and HMQC data were collected on the AMX-600 spectrometer. Thin-layer chromatography (TLC) was performed on 0.25 mm Analtech GHLF silica gel plates. Spots on TLC were visualized with vanillin/H 2 SO 4 in EtOH. Silica Gel (32-63μ particle size) from Bodman Industries (Atlanta, Ga.) was used for column chromatography. HPLC was carried out on an Agilent 1100 Series Capillary HPLC system with diode array detector. Peaks were detected at 209, 214 and 254 nm. MPLC was performed on a RT Scientific PurChrom 150-GCS system equipped with a silica gel column (1.1 cm×30 cm). Elemental analyses were performed by Atlantic Microlabs, Norcross, Ga.
Example 1
Preparation of 1-Deoxy-1,10-dehydro-salvinorin A (1)
[0104]
[0105] To a stirred solution of 1α-hydroxysalvinorin A (3, 291 mg, 0.67 mmol) and DMAP (488 mg, 4 mmol) in dry acetonitrile (6 mL) under argon was added methanesulfonic anhydride (313 mg, 1.8 mmoles). The reaction was stirred at reflux for 1 h, when complete conversion to the mesylate was indicated by TLC. This was followed by the addition of trimethyphenylammonium chloride (257 mg, 1.5 mmoles) and another 1 hour of reflux. The reaction mixture was evaporated and distributed between DCM (8 mL) and 1 M phosphoric acid (35 mL). The organic phase was washed with saturated sodium carbonate solution (20 mL), and the aqueous phases were extracted, in turn with DCM (2×4 mL). The combined and dried (sodium sulfate) organic phases were evaporated to a residue which was purified by column chromatography on silica gel (eluent: DCM/EtOAc, 9:1) gave Compound 1 (213 mg, 0.51 mmol, 76% overall). A portion of the product was recrystallized from EtOAc/hexanes to give pure material, mp 129-131° C.
[0106] The intermediate compound 3 was prepared as follows.
[0000] a. 1α-Hydroxy-Salvinorin A (3). A mixture of salvinorin A (1.7828 g, 4 mmol) and THF (40 mL) was magnetically stirred at gentle reflux for 5 minutes. To this was added an aqueous solution of sodium borohydride (760 mg, 20 mmoles in 6 mL) in portions. After stirring at reflux for 10 minutes following the first addition, a second addition of aqueous sodium borohydride was made (152 mg, 4 mmol in 0.7 mL) and reflux was continued for 5 minutes. The reaction mixture was immediately chilled in an ice bath and progress of the reaction was checked by TLC. The reaction was mixture diluted with ethyl acetate (50 mL) and extracted with saturated sodium chloride (2×30 mL). The aqueous phases were extracted, in turn, with ethyl acetate (2×15 mL) and the combined organic phases were dried (sodium sulfate) and evaporated to a foam (1.70 g). The crude product was chromatographed on silica (50 g) packed in DCM containing 10% EtOAc. Elution with DCM containing increasing amounts of EtOAc gave fractions that were combined based on TLC analysis. Early fractions contained the desired product (1.34 g, 3.08 mmoles, 77%) contaminated with a small amount of starting material, while later fractions contained lactols (158 mg, 0.36 mmole, 9%) reduced at C-17 as well as C-1, and finally an isomer of the desired product (161 mg, 0.37 mmole, 9%) in which the acetate group has migrated from C-2 to C-1. A sample of the major product, 1α-hydroxy-SVA (3) was crystallized from EtOAc/hexanes, mp 110-111° C.
Example 2
Preparation of 1-Deoxy-1,10-dehydrosalvinorin B (2)
[0107]
[0108] A stirred solution of DMAP (122 mg, 1 mmole) in DMSO (3 mL) under argon was rapidly heated to 170° C. After 3 min, compound 6 (240 mg, 0.50 mmole) was added and stirring was continued for 10 min. The rapidly cooled reaction mixture was poured into a mixture of saturated aqueous NaCl (40 mL) and 1 M phosphoric acid (7 mL). The resulting aqueous mixture was extracted with EtOAc (20 mL) and the organic phase was washed with a mixture of saturated NaCl (20 mL) and saturated NaHCO 3 (7 mL). The aqueous phases were extracted, in turn, with EtOAc (10 mL). The combined organic phases were dried (Na 2 SO 4 ) and evaporated to a residue (208 mg), which was purified by column chromatography, eluting with CH 2 Cl 2 containing increasing amounts of EtOAc to afford 143 mg (76%) of 2 and 43 mg (22%) of 8.
[0109] 1-Deoxy-1,10-dehydrosalvinorin B (2). mp 121-122° C. (EtOAc/hexanes); 1 H NMR (CDCl 3 ): 1.34 (s, 3H); 1.35 (s, 3H); 1.43 (dd, J=3.6, 13.5 Hz, 1H); 1.91 (m, 4H); 2.13 (m, 1H); 2.18 (m, 1H); 2.23 (dd, J=3.7, 6.5 Hz, 1H); 2.42 (d, J=13.5 Hz, 1H); 2.44 (dd, J=6.0, 13.5 Hz, 1H); 4.35 (m, 1H); 5.50 (d, J=2.1 Hz, 1H); 5.55 (dd, J=5.4, 12.0 Hz, 1H); 6.43 (dd, J=0.9, 1.8 Hz, 1H); 7.43 (dd, J=1.5, 1.8 Hz, 1H); 7.47 (dd, J=0.9, 1.5 Hz, 1H); 13 C NMR (CDCl 3 ): δ 18.74, 21.98, 23.26, 31.14, 37.43, 38.58, 38.96, 43.15, 50.24, 51.81, 52.88, 67.53, 72.05, 108.67, 124.24, 125.79, 139.67, 144.04, 150.15, 172.47, 173.50
[0110] Compound 8 is an intermediate that is useful for preparing other salvinorin derivatives. 2-keto-1-deoxysalvinorin A (8). mp 227-228° C. (EtOAc/hexanes); 1 H NMR (CDCl 3 ): δ 1.12 (s, 3H); 1.26 (s, 3H); 1.41 (dd, J=3.9, 12.9 Hz, 1H); 1.49 (dd, J=6.6, 8.1 Hz, 1H); 1.66 (m, 2H); 1.82 (dt, J=3.0, 13.5 Hz, 1H); 2.15 (dd, J=3.0, 6.0 Hz, 1H); 2.19 (dd, J=3.0, 5.4 Hz, 1H); 2.23 (dd, J=5.4, 13.5 Hz, 1H); 2.40 (s, 1H); 2.47 (m, 3H); 2.81 (dd, J=12.6, 15.0 Hz, 1H); 3.71 (s, 3H); 5.48 (dd, J=5.4, 11.4 Hz; 1H); 6.39 (dd, J=1.5, 1.5 Hz, 1H); 7.42 (m, 2H); 13 C NMR (CDCl 3 ): δ 14.50, 14.52, 18.45, 36.62, 37.24, 3796, 38.23, 40.57, 43.70, 51.15, 52.09, 53.97, 55.13, 71.87108.56, 125.69, 139.55, 144.14, 171.65, 172.12, 208.16
[0111] The intermediate compound 6 was prepare as follows.
[0000] a. 1α-Hydroxysalvinorin A (3). A mixture of salvinorin A (1.7828 g, 4 mmoles) and THF (40 mL) was magnetically stirred at gentle reflux for 5 min. To this was added an aqueous solution of NaBH 4 (760 mg, 20 mmoles in 6 mL) in portions. After stirring at reflux for 10 min following the first addition, a second addition of aqueous NaBH 4 was made (152 mg, 4 mmoles in 0.7 mL) and reflux was continued for 5 min. The reaction mixture was immediately chilled in an ice bath and progress of the reaction was checked by TLC. The reaction was mixture diluted with EtOAc (50 mL) and extracted with saturated sodium chloride (2×30 mL). The aqueous phases were extracted, in turn, with EtOAc (2×15 mL) and the combined organic phases were dried (Na 2 SO 4 ) and evaporated to a foam. The crude product was purified by column chromatography (CH 2 Cl 2 with increasing amounts of EtOAc) to give 1.34 g of 3 (77%) as a white solid, mp 110-111° C. The 1 H and 13 C spectra of 3 were in agreement with previously reported data (Valdes, L. J., III, et al., J. Org. Chem. 1984, 49, 4716).
b. 1α-Mesyloxysalvinorin A (5). To a stirred solution of 3 (868 mg, 2 mmoles) in dry acetonitrile (10 mL) under argon was added DMAP (1.098 g, 9 mmoles) followed by methanesulfonic anhydride (696 mg, 4 mmoles). The reaction mixture was heated at reflux for 1 h. After cooling to room temperature, the reaction mixture was diluted with ethyl acetate (40 mL) and extracted with a mixture of 1 M phosphoric acid and saturated NaCl (40 mL, 1:1) followed by a mixture of saturated NaHCO 3 and saturated NaCl (30 mL, 1:2). The aqueous phases were extracted, in turn, with ethyl acetate (2×20 mL), and the combined organic phases were dried (Na 2 SO 4 ) and evaporated to give 1.014 g (99%) of 5 as a foam. A sample was crystallized from CH 2 Cl 2 /EtOH to give pure 5, mp 190-194° C. (dec.); 1 H NMR (CDCl 3 ): δ 1.26 (d, J=1.8 Hz, 1H); 1.32 (s, 3H); 1.43 (s, 3H); 1.58 (s, 3H); 1.69 (m, 2H); 1.89 (m, 2H); 2.08 (d, J=2.7 Hz, 1H); 2.11 (s, 3H); 2.16 (m, 1H); 2.30 (m, 1H); 2.31 (s, 1H); 2.49 (dd, J=5.4, 12.9 Hz, 1H); 3.23 (s, 3H); 3.71 (s, 3H); 4.80 (m, 1H); 5.36 (br s, 1H); 5.56 (dd, J=5.4, 11.4 Hz, 1H); 6.42 (dd, J=0.9, 1.5 Hz, 1H); 7.42 (dd, J=1.5, 1.8 Hz, 1H); 7.47 (dd, J=0.9, 1.8 Hz, 1H).
c. 1α-Mesyloxysalvinorin B (6). A mixture of crude 5 (1.280 g, 2.5 mmoles) was stirred with DCM (2 mL) under argon and a solution of 1 drop of 50% aqueous sodium hydroxide in 8 mL of methanol was added quickly in portions. Crystals of starting material that initially appeared dissolved within 1-2 min and a heavy precipitate of product began to form. The reaction mixture was chilled to −10° C. and after 1 h was filtered to give 844 mg (70%) of 6 as a crystalline product. A sample was recrystallized from CH 2 Cl 2 /EtOH to give pure 6, mp 160-162° C. (dec.); 1 H NMR (CDCl 3 ): 1.18 (s, 1H); 1.31 (s, 3H); 1.43 (s, 3H); 1.57 (s, 3H); 1.65 (m, 2H); 1.86 (m, 2H); 2.05 (m, 1H); 2.16 (m, 1H); 2.20 (s, 1H); 2.48 (d, J=5.4 Hz, 1H); 2.57 (dd, J=5.4, 13.2 Hz, 1H); 3.26 (s, 3H); 3.71 (s, 3H); 5.34 (br s, 1H); 5.55 (dd, J=5.4, 11.7 Hz, 1H); 6.41 (d, J=1.2 Hz, 1H); 7.42 (dd, J=1.5, 1.8 Hz, 1H); 7.46 (s, 1H); 13 C NMR (CDCl 3 ): 16.17, 18.17, 18.72, 28.79, 37.39, 37.48, 39.88, 41.04, 43.90, 51.95, 53.12, 55.04, 55.23, 71.41, 71.94, 79.89, 108.61, 125.56, 139.75, 144.03, 172.47, 173.83
Example 3
Preparation of 2-keto-1-deoxy-1,10-dehydrosalvinorin A (9)
[0112]
[0113] A mixture of compound 2 (253 mg, 0.68 mmole) and manganese dioxide (2 g) in toluene (10 mL) was heated at reflux for 20 min. This was followed by the addition of manganese dioxide (2 g), 20 min reflux, then manganese dioxide (1 g) and a further 20 min reflux. The hot mixture was filtered (filter aide) and the precipitate was washed with EtOAc. The filtrate was evaporated to give the product (198 mg, 0.53 mmole, 78%). A sample was recrystallized from EtOAc to give 9, mp 192-194° C. 1 H NMR (CDCl 3 ): δ 1.41 (s, 3H); 1.48 (s, 3H); 1.63 (dd, J=0.9, 13.5 Hz, 1H); 1.90 (m, 2H); 2.02 (dd, J=1.2, 10.5 Hz, 1H); 2.33 (m, 2H); 2.52 (m, 2H); 2.90 (dd, J=14.4, 24 Hz, 1H); 2.93 (s, 1H); 3.73 (s, 3H); 5.58 (dd, J=5.4, 11.4 Hz, 1H); 5.94 (s, 1H); 6.42 (dd, J=0.9, 1.8 Hz, 1H); 7.44 (dd, J=1.8, 1.8 Hz, 1H); 7.47 (s, 1H); 13 C NMR (CDCl 3 ): δ 18.22, 22.05, 22.51, 36.60, 37.51, 38.16, 39.86, 41.90, 49.19, 52.19, 52.91, 71.66, 108.54, 123.95, 125.37, 139.72, 144.24, 171.02, 172.10, 172.13, 197.68
Example 4
Preparation of 1-Deoxy-1,10-dehydroherkinorin (10)
[0114]
[0115] A solution of 2 (0.050 g, 0.134 mmol), benzoyl chloride (0.056 g, 0.401 mmol), Net 3 (0.020 g, 0.200 mmol) and a catalytic amount of DMAP in CH 2 Cl 2 (20 mL) was stirred at room temperature overnight. Absolute MeOH (15 mL) was added and the solvent was removed under reduced pressure. CH 2 Cl 2 (25 mL) was added to the residue and the solution was washed with 2N HCl (3×30 mL), 2N NaOH (3×30 mL) and saturated NaCl (2×20 mL) and dried (Na 2 SO 4 ). Removal of the solvent under reduced pressure to afford crude. The residue was purified by column chromatography (eluent: Hexanes/EtOAc, 7:3) to give 0.025 g (40%) of 10 as a white solid, mp 85-87° C.; 1 H NMR (CDCl 3 ): 1.38 (s, 3H); 1.41 (s, 3H); 1.49 (dd, J=4.0, 13.0 Hz, 1H); 1.92 (m, 3H); 2.24 (m, 4H); 2.43 (dd, J=5.4, 13.5 Hz, 1H); 2.57 (dd, J=2.7, 13.2 Hz, 1H); 3.71 (s, 3H); 5.53 (dd, J=5.1, 11.4 Hz, 1H); 5.57 (s, 1H); 5.66 (m, 1H); 6.43 (dd, J=0.9, 1.8 Hz, 1H); 7.42 (dd, J=1.5, 1.8 Hz, 1H); 7.45 (d, J=0.9 Hz, 1H); 7.47 (dt J=0.6, 0.9, 2.4 Hz, 2H); 7.58 (tt, J=1.2, 1.5, 2.4, 7.2 Hz, 1H); 8.05 (dt, J=1.5, 1.8, 6.9 Hz, 2H); HRMS (m/z): [M+H] + calcd for C 28 H 30 O 7 , 478.1992. found, 478.2006.
Example 5
[0116] The following illustrate representative pharmaceutical dosage forms, containing a compound of formula I (‘Compound X’), for therapeutic or prophylactic use in humans.
[0000]
(i) Tablet 1
mg/tablet
Compound X=
100.0
Lactose
77.5
Povidone
15.0
Croscarmellose sodium
12.0
Microcrystalline cellulose
92.5
Magnesium stearate
3.0
300.0
[0000]
(ii) Tablet 2
mg/tablet
Compound X=
20.0
Microcrystalline cellulose
410.0
Starch
50.0
Sodium starch glycolate
15.0
Magnesium stearate
5.0
500.0
[0000]
(iii) Capsule
mg/capsule
Compound X=
10.0
Colloidal silicon dioxide
1.5
Lactose
465.5
Pregelatinized starch
120.0
Magnesium stearate
3.0
600.0
[0000]
(iv) Injection 1 (1 mg/ml)
mg/ml
Compound X = (free acid form)
1.0
Dibasic sodium phosphate
12.0
Monobasic sodium phosphate
0.7
Sodium chloride
4.5
1.0 N Sodium hydroxide solution
q.s.
(pH adjustment to 7.0-7.5)
Water for injection
q.s. ad 1 mL
[0000]
(v) Injection 2 (10 mg/ml)
mg/ml
Compound X = (free acid form)
10.0
Monobasic sodium phosphate
0.3
Dibasic sodium phosphate
1.1
Polyethylene glycol 400
200.0
01 N Sodium hydroxide solution
q.s.
(pH adjustment to 7.0-7.5)
Water for injection
q.s. ad 1 mL
[0000] (vi) Aerosol mg/can Compound X= 20.0 Oleic acid 10.0 Trichloromonofluoromethane 5,000.0 Dichlorodifluoromethane 10,000.0 Dichlorotetrafluoroethane 5,000.0
The above formulations may be obtained by conventional procedures well known in the pharmaceutical art.
[0117] All publications, patents, and patent documents are incorporated by reference herein, as though individually incorporated by reference. The invention has been described with reference to various specific embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention.
|
The invention provides novel compounds of formula I: that are opioid receptor ligands. The invention also provides pharmaceutical compositions comprising such compounds as well as methods for treating diseases associated with opioid receptor function by administering such compounds to a mammal in need of treatment. Compounds of the invention are useful to modulate (e.g. agonize or antagonize) opioid receptor function.
| 2
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a divisional application of U.S. application Ser. No. 11/327,580, filed on Jan. 6, 2006, which is a continuation-in-part of U.S. application Ser. No. 10/629,006, filed Jul. 29, 2003, U.S. application Ser. No. 11/067,167, filed on Feb. 25, 2005, U.S. provisional App. No. 60/689,538 filed on Jun. 13, 2005, and U.S. provisional App. No. 60/689,539 filed on Jun. 13, 2005, all of which are incorporated herein in their entireties by reference.
BACKGROUND OF THE INVENTION
[0002] Fuel cells are devices that directly convert chemical energy of reactants, i.e., fuel and oxidant, into direct current (DC) electricity. For an increasing number of applications, fuel cells are more efficient than conventional power generation, such as combustion of fossil fuel, as well as portable power storage, such as lithium-ion batteries.
[0003] In general, fuel cell technology includes a variety of different fuel cells, such as alkali fuel cells, polymer electrolyte fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, solid oxide fuel cells and enzyme fuel cells. Today's more important fuel cells can be divided into several general categories, namely (i) fuel cells utilizing compressed hydrogen (H 2 ) as fuel; (ii) proton exchange membrane (PEM) fuel cells that use alcohols, e.g., methanol (CH 3 OH), metal hydrides, e.g., sodium borohydride (NaBH 4 ), hydrocarbons, or other fuels reformed into hydrogen fuel; (iii) PEM fuel cells that can consume non-hydrogen fuel directly or direct oxidation fuel cells; and (iv) solid oxide fuel cells (SOFC) that directly convert hydrocarbon fuels to electricity at high temperature.
[0004] Compressed hydrogen is generally kept under high pressure and is therefore difficult to handle. Furthermore, large storage tanks are typically required and cannot be made sufficiently small for consumer electronic devices. Conventional reformat fuel cells require reformers and other vaporization and auxiliary systems to convert fuels to hydrogen to react with oxidant in the fuel cell. Recent advances make reformer or reformat fuel cells promising for consumer electronic devices. The most common direct oxidation fuel cells are direct methanol fuel cells or DMFC. Other direct oxidation fuel cells include direct ethanol fuel cells and direct tetramethyl orthocarbonate fuel cells. DMFC, where methanol is reacted directly with oxidant in the fuel cell, is the simplest and potentially smallest fuel cell and also has promising power application for consumer electronic devices. SOFC convert hydrocarbon fuels, such as butane, at high heat to produce electricity. SOFC requires relatively high temperature in the range of 1000° C. for the fuel cell reaction to occur.
[0005] The chemical reactions that produce electricity are different for each type of fuel cell. For DMFC, the chemical-electrical reaction at each electrode and the overall reaction for a direct methanol fuel cell are described as follows:
[0006] Half-reaction at the anode:
[0000] CH 3 OH+H 2 O→CO 2 +6H + +6 e −
[0007] Half-reaction at the cathode:
[0000] 1.5O 2 +6H + 6 e − 3H 2 O
[0008] The overall fuel cell reaction:
[0000] CH 3 OH+1.5O 2 →CO 2 +2H 2 O
[0009] Due to the migration of the hydrogen ions (H + ) through the PEM from the anode to the cathode and due to the inability of the free electrons (e − ) to pass through the PEM, the electrons flow through an external circuit, thereby producing an electrical current through the external circuit. The external circuit may be used to power many useful consumer electronic devices, such as mobile or cell phones, calculators, personal digital assistants, laptop computers, and power tools, among others.
[0010] DMFC is discussed in U.S. Pat. Nos. 5,992,008 and 5,945,231, which are incorporated by reference herein in their entireties. Generally, the PEM is made from a polymer, such as Nafion® available from DuPont, which is a perfluorinated sulfonic acid polymer having a thickness in the range of about 0.05 mm to about 0.50 mm, or other suitable membranes. The anode is typically made from a Teflonized carbon paper support with a thin layer of catalyst, such as platinum-ruthenium, deposited thereon. The cathode is typically a gas diffusion electrode in which platinum particles are bonded to one side of the membrane.
[0011] In another direct oxidation fuel cell, borohydride fuel cell (DBFC) reacts as follows:
[0012] Half-reaction at the anode:
[0000] BH 4− +8OH − →BO 2− +6H 2 O+8 e −
[0013] Half-reaction at the cathode:
[0000] 2O 2 +4H 2 O+8 e − →8OH −
[0014] In a chemical metal hydride fuel cell, sodium borohydride is reformed and reacts as follows:
[0000] NaBH 4 +2H 2 O (heat or catalyst)→4(H 2 )+(NaBO 2 )
[0015] Half-reaction at the anode:
[0000] H 2 →2H + +2 e −
[0016] Half-reaction at the cathode:
[0000] 2(2H + +2 e − )+O 2 →2H 2 O
[0017] Suitable catalysts for this reaction include platinum and ruthenium, and other metals. The hydrogen fuel produced from reforming sodium borohydride is reacted in the fuel cell with an oxidant, such as O 2 , to create electricity (or a flow of electrons) and water by-product. Sodium borate (NaBO 2 ) by-product is also produced by the reforming process. A sodium borohydride fuel cell is discussed in U.S. Pat. No. 4,261,956, which is incorporated by reference herein in its entirety.
[0018] One of the most important features for fuel cell application is fuel storage. Another important feature is to regulate the transport of fuel out of the fuel cartridge to the fuel cell. To be commercially useful, fuel cells such as DMFC or PEM systems should have the capability of storing sufficient fuel to satisfy the consumers' normal usage. For example, for mobile or cell phones, for notebook computers, and for personal digital assistants (PDAs), fuel cells need to power these devices for at least as long as the current batteries and, preferably, much longer. Additionally, the fuel cells should have easily replaceable or refillable fuel tanks to minimize or obviate the need for lengthy recharges required by today's rechargeable batteries.
[0019] One disadvantage of the known hydrogen gas generators is that once the reaction starts the gas generator cartridge cannot control the reaction. Thus, the reaction will continue until the supply of the reactants run out or the source of the reactant is manually shut down.
[0020] Accordingly, there is a desire to obtain a hydrogen gas generator apparatus that is capable of self-regulating the flow of at least one reactant into the reaction chamber and other devices to regulate the flow of fuel.
SUMMARY OF THE INVENTION
[0021] The present application is directed to a gas-generating apparatus and various pressure regulators or pressure-regulating valves. Hydrogen is generated within the gas-generating apparatus and is transported to a fuel cell. The transportation of a first fuel component to a second fuel component to generate of hydrogen occurs automatically depending on the pressure of a reaction chamber within the gas-generating apparatus. The pressure regulators, including flow orifices, are provided to regulate the hydrogen pressure and to minimize the fluctuation in pressure of the hydrogen received by the fuel cell. Connecting valves to connect the gas-generating apparatus to the fuel cell are also provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:
[0023] FIG. 1 is a cross-sectional schematic view of a gas-generating apparatus according to the present invention; FIG. 1A is an enlarged partial cross-sectional view of a solid fuel container for use in the gas-generating apparatus of FIG. 1 ; FIG. 1B is an enlarged partial cross-sectional view of an alternate solid fuel container for use in the gas-generating apparatus of FIG. 1 ; FIG. 1C is an alternate embodiment of FIG. 1B ; FIG. 1D is a cross-sectional view of an alternate embodiment of a fluid conduit;
[0024] FIG. 2A is a cross-sectional view of a shut-off or connection valve for use in the gas-generating apparatus of FIG. 1 shown in the disconnected and closed position; FIG. 2B is a cross-sectional view of the shut-off valve shown in FIG. 2A shown in the connected and open position;
[0025] FIG. 3 is a cross-sectional view of a pressure-regulated fluid nozzle or valve for use in the gas-generating apparatus of FIG. 1 ;
[0026] FIG. 4A is a cross-sectional view of a pressure-regulating valve for use in the gas-generating apparatus of FIG. 1 ; FIG. 4B is an exploded perspective view of the pressure-regulating valve of FIG. 4A ; FIG. 4C is a cross-sectional view of an alternate pressure-regulating valve; FIG. 4D is an exploded perspective view of the pressure-regulating valve of FIG. 4C ;
[0027] FIG. 5A is a cross-sectional view of another pressure-regulating valve connected to a first valve component of the shut-off valve of FIG. 2 ; FIGS. 5B-D are cross-sectional views showing the pressure-regulating valve and the first valve component with a second valve component of the shut-off valve in the unconnected, connected/closed and connected/open positions;
[0028] FIG. 6A is a cross-sectional view of a pressure-regulating valve for use in the gas-generating apparatus of FIG. 1 ; FIG. 6B is an exploded view of the pressure-regulating valve of FIG. 6A ; and
[0029] FIGS. 7A and 7B are cross-sectional views of a variable diameter orifice for use with the pressure-regulating valves of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] As illustrated in the accompanying drawings and discussed in detail below, the present invention is directed to a fuel supply, which stores fuel cell fuels, such as methanol and water, methanol/water mixture, methanol/water mixtures of varying concentrations, pure methanol, and/or methyl clathrates described in U.S. Pat. Nos. 5,364,977 and 6,512,005 B2, which are incorporated by reference herein in their entirety. Methanol and other alcohols are usable in many types of fuel cells, e.g., DMFC, enzyme fuel cells and reformat fuel cells, among others. The fuel supply may contain other types of fuel cell fuels, such as ethanol or alcohols; metal hydrides, such as sodium borohydrides; other chemicals that can be reformatted into hydrogen; or other chemicals that may improve the performance or efficiency of fuel cells. Fuels also include potassium hydroxide (KOH) electrolyte, which is usable with metal fuel cells or alkali fuel cells, and can be stored in fuel supplies. For metal fuel cells, fuel is in the form of fluid borne zinc particles immersed in a KOH electrolytic reaction solution, and the anodes within the cell cavities are particulate anodes formed of the zinc particles. KOH electrolytic solution is disclosed in U.S. Pat. App. Pub. No. US 2003/0077493, entitled “Method of Using Fuel Cell System Configured to Provide Power to One or More Loads,” published on Apr. 24, 2003, which is incorporated by reference herein in its entirety. Fuels can also include a mixture of methanol, hydrogen peroxide and sulfuric acid, which flows past a catalyst formed on silicon chips to create a fuel cell reaction. Moreover, fuels include a blend or mixture of methanol, sodium borohydride, an electrolyte, and other compounds, such as those described in U.S. Pat. Nos. 6,554,877, 6,562,497 and 6,758,871, which are incorporated by reference herein in their entireties. Furthermore, fuels include those compositions that are partially dissolved in a solvent and partially suspended in a solvent, described in U.S. Pat. No. 6,773,470 and those compositions that include both liquid fuel and solid fuels, described in U.S. Pat. Appl. Pub. No. US 2002/0076602. Suitable fuels are also disclosed in co-owned, co-pending U.S. Pat. Appl. No. 60/689,572, entitled “Fuels for Hydrogen-Generating Cartridges,” filed on Jun. 13, 2005. These references are also incorporated by reference herein in their entireties.
[0031] Fuels can also include a metal hydride such as sodium borohydride (NaBH 4 ) and water, discussed above. Fuels can further include hydrocarbon fuels, which include, but are not limited to, butane, kerosene, alcohol, and natural gas, as set forth in U.S. Pat. Appl. Pub. No. US 2003/0096150, entitled “Liquid Hereto-Interface Fuel Cell Device,” published on May 22, 2003, which is incorporated by reference herein in its entirety. Fuels can also include liquid oxidants that react with fuels. The present invention is therefore not limited to any type of fuels, electrolytic solutions, oxidant solutions or liquids or solids contained in the supply or otherwise used by the fuel cell system. The term “fuel” as used herein includes all fuels that can be reacted in fuel cells or in the fuel supply, and includes, but is not limited to, all of the above suitable fuels, electrolytic solutions, oxidant solutions, gaseous, liquids, solids, and/or chemicals including additives and catalysts and mixtures thereof.
[0032] As used herein, the term “fuel supply” includes, but is not limited to, disposable cartridges, refillable/reusable cartridges, containers, cartridges that reside inside the electronic device, removable cartridges, cartridges that are outside of the electronic device, fuel tanks, fuel refilling tanks, other containers that store fuel and the tubings connected to the fuel tanks and containers. While a cartridge is described below in conjunction with the exemplary embodiments of the present invention, it is noted that these embodiments are also applicable to other fuel supplies and the present invention is not limited to any particular type of fuel supply.
[0033] The fuel supply of the present invention can also be used to store fuels that are not used in fuel cells. These applications can include, but are not limited to, storing hydrocarbons and hydrogen fuels for micro gas-turbine engines built on silicon chips, discussed in “Here Come the Microengines,” published in The Industrial Physicist (December 2001/January 2002) at pp. 20-25. As used in the present application, the term “fuel cell” can also include microengines. Other applications can include storing traditional fuels for internal combustion engines and hydrocarbons, such as butane for pocket and utility lighters and liquid propane.
[0034] Suitable known hydrogen-generating apparatus are disclosed in commonly-owned, co-pending U.S. Pat. Appl. Pub. No. US 2005-0074643 A1 and U.S. Pat. Appl. Pub. No. US 2005-0266281, and co-pending U.S. patent application Ser. No. 11/066,573 filed on Feb. 25, 2005. The disclosures of these references are incorporated by reference herein in their entireties.
[0035] The gas-generating apparatus of the present invention may include a reaction chamber, which may include an optional first reactant, and a reservoir having a second reactant. The first and second reactants can be a metal hydride, e.g., sodium borohydride, and water. The reactants can be in gaseous, liquid, aqueous or solid form. Preferably, the first reactant stored in the reaction chamber is a solid metal hydride or metal borohydride with selected additives and catalysts such as ruthenium, and the second reactant is water optionally mixed with selected additives and catalysts. Water and metal hydride of the present invention react to produce hydrogen gas, which can be consumed by a fuel cell to produce electricity. Other suitable reactants or reagents are disclosed in the parent applications, previously incorporated above.
[0036] Additionally, the gas-generating apparatus can include a device or system that is capable of controlling the transport of a second reactant from the reservoir to the reaction chamber. The operating conditions inside the reaction chamber and/or the reservoir, preferably a pressure inside the reaction chamber, are capable of controlling the transport of the second reactant in the reservoir to the reaction chamber. For example, the second reactant in the reservoir can be introduced into the reaction chamber when the pressure inside the reaction chamber is less than a predetermined value, preferably less than the pressure in the reservoir, and, more preferably less than the pressure in the reservoir by a predetermined amount. It is preferable that the flow of the second reactant from the reservoir into the reaction chamber is self-regulated. Thus, when the reaction chamber reaches a predetermined pressure, preferably a predetermined pressure above the pressure in the reservoir, the flow of the second reactant from the reservoir into the reaction chamber can be stopped to stop the production of hydrogen gas. Similarly, when the pressure of the reaction chamber is reduced below the pressure of the reservoir, preferably below the pressure in the reservoir by a predetermined amount, the second reactant can flow from the reservoir into the reaction chamber. The second reactant in the reservoir can be introduced into the reaction chamber by any known method including, but not limited to, pumping, osmosis, capillary action, pressure differential valves, other valve(s), or combinations thereof. The second reactant can also be pressurized with springs or pressurized liquids and gases. Preferably, the second reactant is pressurized with liquefied hydrocarbons, such as liquefied butane.
[0037] Referring to FIG. 1 , an inventive fuel supply system is shown. The system includes a gas-generating apparatus 12 contained within a housing 13 and is configured to be connected to a fuel cell (not shown) via a fuel conduit 16 and a valve 34 . Preferably, fuel conduit 16 initiates within gas-generating apparatus 12 , and valve 34 is in fluid communication with conduit 16 . Fuel conduit 16 can be a flexible tube, such as a plastic or rubber tube, or can be a substantially rigid part connected to housing 13 .
[0038] Within housing 13 , gas-generating apparatus 12 preferably includes two main compartments: a fluid fuel component reservoir 44 containing a fluid fuel component 22 and a reaction chamber 18 containing a solid fuel component 24 . Reservoir 44 and reaction chamber 18 are sealed off from one another until the production of a fuel gas, such as hydrogen, is desired by reacting fluid fuel component 22 with solid fuel component 24 . Housing 13 is preferably divided by interior wall 19 to form fluid reservoir 44 and reaction chamber 18 .
[0039] Reservoir 44 may preferably, however, include a liner, bladder or similar fluid container 21 to contain fluid or liquid fuel component 22 as shown. Fluid fuel component 22 preferably includes water and/or an additive/catalyst or other liquid reactants. Additional appropriate fluid fuel components and additives are further discussed herein. Suitable additives/catalysts include, but are not limited to, anti-freezing agents (e.g., methanol, ethanol, propanol and other alcohols), catalysts (e.g., cobalt chloride and other known catalysts), pH adjusting agents (e.g., acids such as sulfuric acid and other common acids). Preferably, fluid fuel component 22 is pressurized, such as by springs or by pressurized/liquefied gas (butane or propane), although it may also be unpressurized. When liquefied hydrocarbon is used, it is injected into reservoir 44 and is contained in the space between liner 21 and housing 13 .
[0040] Reservoir 44 and reaction chamber 18 are fluidly connected by a fluid transfer conduit 88 . Fluid transfer conduit 88 is connected to conduit 15 , which is in fluid communication with liquid fuel component 22 within liner 21 , and one or more conduits 17 , which brings the liquid fuel component 22 into contact with the solid fuel component 24 . Orifice 15 can be connected directly to conduit 88 , or as shown in FIG. 1 it can be connected to a channel 84 defined on the outside surface of plug 86 which defines conduit 88 therewithin. Hole 87 connects surface channel 84 to conduit 88 . The function of plug 86 is further defined hereafter. Fluid transfer conduit 88 can also be a channel or similar void formed in housing 13 , or external tubing located outside of housing 13 . Other configurations are also appropriate.
[0041] Reaction chamber 18 is contained within housing 13 and separated from fluid fuel component reservoir 44 by interior wall 19 and is preferably made of a fluid impenetrable material, such as a metal, for example, stainless steel, or a resin or plastic material. As liquid fuel component 22 and solid fuel component 24 are mixed within reaction chamber 18 to produce a fuel gas, such as hydrogen, reaction chamber 18 also preferably includes a pressure relief valve 52 located in housing 13 . Pressure relief valve 52 is preferably a pressure-triggered valve, such as a check valve or a duckbill valve, which automatically vents produced fuel gas should the pressure within reaction chamber, P 18 , reach a specified triggering pressure. Another pressure relief valve can be installed on fluid fuel component reservoir 44 .
[0042] Solid fuel component 24 , which can be powders, granules, or other solid forms, is disposed within a solid fuel container 23 , which, in this embodiment, is a gas permeable bladder, liner or bag. Fillers and other additives and chemicals can be added to solid fuel component 24 to improve its reaction with the liquid reactant. Preferably, additives that can be corrosive to valves and other elements within fluid transfer conduit 88 , conduits 15 and 17 should be included with solid fuel 24 . Solid fuel component 24 is packed inside solid fuel container 23 , which is preferably cinched or wrapped tightly around one or more fluid dispersion elements 89 ; for example with rubber or elastic bands, such as rubber or metal bands, with heat shrunk wraps, pressure adhesive tapes or the like. Solid fuel container 23 can also be formed by thermoform. In one example, solid fuel container 23 comprises a plurality of films that are selectively perforated to control the flow of liquid reactant, gas and/or by-products therethrough. Each fluid dispersion element 89 is in fluid communication with conduits 17 , within which the liquid fuel is transported to the solid fuel. Dispersion element 89 is preferably a rigid tube-like hollow structure made of a non-reactive material having openings 91 along its length and at its tip to assist in the maximum dispersal of fluid fuel component 22 to contact solid fuel component 24 . Preferably, at least some of the openings 91 in fluid dispersion element 89 include capillary fluid conduits 90 , which are relatively small tubular extensions to disperse the fluid even more effectively throughout solid fuel component 24 . Capillary conduits 90 can be fillers, fibers, fibrils or other capillary conduits. Each fluid dispersion element 89 is supported within reaction chamber 18 by a mount 85 , which is also the point at which fluid dispersion element 89 is connected to conduits 17 and to fluid transfer conduit 88 .
[0043] The inner diameter of fluid dispersion element 89 is sized and dimensioned to control the volume and speed that liquid fuel component 22 is transported therethrough. In certain instances, the effective inner diameter of element 89 needs to be sufficiently small, such that the manufacture of such a small tube may be difficult or expensive. In such instances, a larger tube 89 a can be used with a smaller rod 89 b disposed within the larger tube 89 a to reduce the effective inner diameter of the larger tube 89 a . The liquid fuel component is transported through the annular space 89 c between the tube and the inner rod, as shown in FIG. 1D .
[0044] In another embodiment, to increase the permeability of the liquid fuel component 22 through the solid fuel component 24 , hydrophilic materials, such as fibers, foam chopped fibers or other wicking materials, can be intermixed with the solid fuel component 24 . The hydrophilic materials can form an interconnected network within solid fuel component 24 , but the hydrophilic materials do not need to contact each other within the solid fuel component to improve permeability.
[0045] Solid fuel container 23 may be made of many materials and can be flexible or substantially rigid. In the embodiment shown in FIG. 1A , solid fuel container 23 is preferably made of a single layer 54 of a gas-permeable, liquid impermeable material such as CELGARD® and GORE-TEX. Other gas permeable, liquid impermeable materials usable in the present invention include, but are not limited to, SURBENT® Polyvinylidene Fluoride (PVDF) having a porous size of from about 0.1 μm to about 0.45 μm, available from Millipore Corporation. The pore size of SURBENT® PVDF regulates the amount of liquid fuel component 22 or water exiting the system. Materials such as electronic vent-type material having 0.2 μm hydro, available from W. L. Gore & Associates, Inc., may also be used in the present invention. Additionally, sintered and/or ceramic porous materials having a pore size of less than about 10 μm, available from Applied Porous Technologies Inc., are also usable in the present invention. Additionally, or alternatively, the gas permeable, liquid impermeable materials disclosed in commonly owned, co-pending U.S. patent application Ser. No. 10/356,793 are also usable in the present invention, all of which are incorporated by reference herein in their entireties. Using such materials allows for the fuel gas produced by the mixing of fluid fuel component 22 and solid fuel component 24 to vent through solid fuel container 23 and into reaction chamber 18 for transfer to the fuel cell (not shown), while restricting the liquid and/or paste-like by-products of the chemical reaction to the interior of solid fuel container 23 .
[0046] FIG. 1B shows an alternate construction for solid fuel container 23 . In this embodiment, the walls of solid fuel container 23 are made of multiple layers: an outer layer 57 and an inner layer 56 separated by an absorbent layer 58 . Both inner layer 56 and outer layer 57 may be made of any material known in the art capable of having at least one slit 55 formed therein. Slits 55 are openings in inner layer 56 and outer layer 57 to allow the produced fuel gas to vent from solid fuel container 23 . To minimize the amount of fluid fuel component 22 and/or paste-like by-products that may exit through slits 55 , absorbent layer 58 is positioned between inner layer 56 and outer layer 57 to form a barrier. Absorbent layer 58 may be made from any absorbent material known in the art, but is preferably capable of absorbing liquid while allowing gas to pass through the material. One example of such a material is paper fluff containing sodium polyacrylate crystals; such a material is commonly used in diapers. Other examples include, but are not limited to, fillers, non-wovens, papers and foams. As will be recognized by those in the art, solid fuel container 23 may include any number of layers, alternating between layers containing slits 55 and absorbent layers.
[0047] In one example shown in FIG. 1C , solid fuel component 24 is encased in four layers 54 a , 54 b , 54 c and 54 d . These layers are preferably gas permeable and liquid impermeable. Alternatively, each layer can be made from any material with a plurality of holes or slits 55 , as shown, to allow the produced gas to pass through. Disposed between adjacent layers 54 a - d are absorbent layers 58 . In this embodiment, the flow path for the produced gas and the by-products, if any, is made tortuous to encourage more liquid fuel component 22 to remain in contact with solid fuel component 24 longer to produce more gas. As shown, while the innermost layer 54 a is perforated on both sides, the next layer 54 b is perforated only on one side. The next layer 54 c is also perforated on one side, but opposite to the perforated side of layer 54 b . Layer 54 d is perforated on one side, but opposite to the perforated side of layer 54 c and so on. Alternatively, instead of using partially perforated layers 54 a - b wrapping around solid fuel component 24 , liners or bags made with a permeable portion and non-permeable portion can be used instead, with the permeable portion of one liner located opposite from the permeable portion of the next outer layer.
[0048] Disposed within fluid transfer conduit 88 is preferably a fluid transfer valve 33 to control the flow of fluid fuel component 22 into reaction chamber 18 . Fluid transfer valve 33 may be any type of pressure-opened, one-way valve known in the art, such as a check valve (as shown in FIG. 1 ), a solenoid valve, a duckbill valve, a valve having a pressure responsive diaphragm, which opens when a threshold pressure is reached. Fluid transfer valve 33 may be opened by user intervention and/or triggered automatically by pressurized fluid fuel component 22 . In other words, fluid transfer valve 33 acts as an “on/off” switch for triggering the transfer of fluid fuel component 22 to reaction chamber 18 . In this embodiment, a fluid transfer valve 33 is a check valve including a biasing spring 35 pushing a ball 36 against a sealing surface 37 . Preferably, a deformable sealing member 39 such as an O-ring is also included to assure a seal. Shown as overlapped areas in FIG. 1 are the portions of valve 33 that would be compressed to form a seal. Plug 86 , discussed above, is used in an exemplary method of assembling valve 33 . A channel is formed in the bottom end of housing 13 for fluid transfer conduit 88 . First, spring 35 is inserted in this channel, followed by ball 36 and sealing member 39 . Plug 86 is finally inserted in this channel to compress spring 35 and presses against ball 36 and sealing member 39 to form a seal with valve 33 . Parts of plug 86 , i.e., hole 87 and peripheral channel 84 , connect fluid transfer conduit 88 to conduit 15 to reach liquid fuel component 22 .
[0049] In this embodiment, fluid transfer valve 33 opens when the fluid pressure within reservoir 44 exceeds the pressure of reaction chamber 18 by a predetermined amount. As reservoir 44 is preferably pressurized, this triggering pressure is exceeded immediately upon pressurizing reservoir 44 . To stop fluid transfer valve 33 from opening before fuel gas is desired to be produced, a stopping mechanism (not shown), such as a latch or a pull tab, may be included, so that the first user of fuel supply 12 may start the transfer of fluid fuel component 22 by releasing the stopping mechanism. Alternatively, chamber 18 is pressurized with an inert gas or hydrogen to equalize the pressure across valve 33 within said predetermined amount.
[0050] Fuel conduit 16 is attached to housing 13 as shown by any method known in the art. Optionally, a gas-permeable, liquid impermeable membrane 32 may be affixed over the reaction chamber-facing side of conduit 16 . Membrane 32 limits the amount of liquids or by-products from being transferred out of gas generating apparatus 12 to the fuel cell via fuel conduit 16 . Fillers or foam can be used in combination with membrane 32 to retain liquids or by-products and to reduce clogging. Membrane 32 may be formed from any liquid impermeable, gas permeable material known to one skilled in the art. Such materials can include, but are not limited to, hydrophobic materials having an alkane group. More specific examples include, but are not limited to: polyethylene compositions, polytetrafluoroethylene, polypropylene, polyglactin (VICRY®), lyophilized dura mater, or combinations thereof. Gas permeable member 32 may also comprise a gas permeable/liquid impermeable membrane covering a porous member. Such a membrane 32 may be used in any of the embodiments discussed herein. Valve 34 can be any valve, such as a pressure-triggered valve (a check valve or a duckbill valve) or a pressure-regulating valve or pressure regulator described below. When valve 34 is a pressure-triggered valve (such as valve 33 ), no fuel can be transferred until P 18 reaches a threshold pressure. Valve 34 may be positioned in fuel conduit 16 as shown in FIG. 1 , or can be located remote from gas-generating device 12 .
[0051] A connection valve or shut-off valve 27 may also be included, preferably in fluid communication with valve 34 . As shown in FIG. 2A , connection valve 27 is preferably a separable valve having a first valve component 60 and a second valve component 62 . Each valve component 60 , 62 has an internal seal. Further, first valve component 60 and second valve component 62 are configured to form an intercomponent seal therebetween before being opened. Connection valve 27 is similar to the shut-off valves described in parent '006 application. Connection valve 27 is shaped and dimensioned for transporting gas.
[0052] First valve component 60 includes a housing 61 and housing 61 defines a first flow path 79 through its interior. Disposed within first flow path 79 is a first slidable body 64 . Slidable body 64 is configured to seal first flow path 79 by pressing a sealing surface 69 against a deformable sealing member 70 , such as an O-ring, disposed in first flow path 79 near a shoulder 82 formed by the configuration of first flow path 79 . Slidable body 64 is biased toward shoulder 82 formed on a second end of first valve component 60 to secure the seal formed at sealing surface 69 . Slidable body 64 will remain in this biased position until first valve component 60 and second valve component 62 are engaged. Alternatively, slidable body 64 is made from an elastomeric material to form a seal and sealing member 70 can be omitted.
[0053] An elongated member 65 extends from one end of slidable body 64 , as shown. Elongated member 65 is a needle-like extension that protrudes from housing 61 . Elongated member 65 is preferably covered with a tubular sealing surface 67 . A space or void is formed in the annular space between elongated member 65 and tubular sealing surface 67 to extend first flow path 79 outside of housing 61 . Tubular sealing surface 67 is connected to elongated member 65 with optional spacers or ribs (not shown) so as not to close off first flow path 79 . Elongated member 65 and tubular sealing surface 67 are configured to be inserted into second valve component 62 .
[0054] Second valve component 62 is similar to first valve component 60 and includes a housing 63 made of a substantially rigid material. Housing 63 defines a second flow path 80 through its interior. Disposed within second flow path 80 is a second slidable body 74 . Slidable body 74 is configured to seal second flow path 80 by pressing a sealing surface 75 against a deformable sealing member 73 near a shoulder 83 . Slidable body 74 is biased to the sealing position by spring 76 . Second valve component 62 thus remains sealed until first valve component 60 and second valve component 62 are correctly connected. Alternatively, slidable body 74 is made from an elastomeric material to form a seal and sealing member 73 can be omitted.
[0055] A pin 81 extends from the other end of slidable body 74 . Pin 81 is a needle-like extension and remains within housing 63 , and does not seal second flow path 80 . Pin 81 is also sized and dimensioned to engage with elongated member 65 when first valve component 60 and second valve component 62 are engaged. A sealing member 71 , such as an O-ring, may be positioned between pin 81 and the interface end of second valve component 62 so that a seal is formed around tubular sealing surface 67 before and during the period when first valve component 60 and second valve component 62 are engaged.
[0056] To open first valve component 60 and second valve component 62 to form a single flow path therethrough, first valve component 60 is inserted into second valve component 62 or vice versa. As the two valve components 60 , 62 are pushed together, elongated member 65 engages with pin 81 , which press against each other to move first slidable body 64 away from shoulder 82 and second slidable body 74 away from shoulder 83 . As such, sealing members 70 and 73 are disengaged to allow fluid to flow through first flow path 79 and second flow path 80 , as shown in FIG. 2B .
[0057] First valve component 60 and second valve component 62 are configured such that an inter-component seal is formed between tubular sealing surface 67 and sealing member 71 , before preferably either sealing surface 69 of first slidable body 64 or sealing surface 75 of second slidable body 74 are disengaged from sealing members 70 and 73 , respectively.
[0058] A first end of housing 61 and a second end of housing 63 preferably include barbs 92 a and 92 b , respectively, for easy and secure insertion into fuel conduit 16 . Alternatively, barbs 92 a and 92 b may be any secure connector known in the art, such as threaded connectors or press fit connectors. Additional configurations for connection valves are more fully described in the parent '006 application, also published as U.S. Pat. App. Pub. US 2005/0022883 A1, previously incorporated by reference.
[0059] Retainer 77 is positioned on the interface end of second valve component 62 . Retainer 77 may also be a sealing member, such as an O-ring, a gasket, a viscous gel, or the like. Retainer/sealing member 77 is configured to engage front sealing surface 78 on first valve component 60 to provide another inter-component seal.
[0060] One of valve components 60 and 62 can be integrated with a fuel supply, and the other valve component can be connected to a fuel cell or a device powered by the fuel cell. Either valve component 60 and/or 62 can also be integrated with a flow or pressure regulator or pressure-regulating valve, discussed below.
[0061] Before the first use, fluid transfer valve 33 , as shown in FIG. 1 , is opened either by removing a pull tab or latch or by removing the initial pressurized gas in chamber 18 . Pressurized fluid fuel component 22 is transferred into reaction chamber 18 via fluid transfer conduit 88 to react with solid fuel component 24 . Pressurized fluid fuel component 22 passes through an orifice 15 and into fluid transfer conduit 88 . While fluid transfer valve 33 is opened, fluid fuel component 22 is continually fed into reaction chamber 18 to create the fuel gas that is then transferred to the fuel cell or the device through fuel conduit 16 . In one embodiment, to halt the production of additional gas, fluid transfer valve 33 can be manually shut-off.
[0062] In another embodiment, one of several pressure-regulating devices may be employed within gas-generating apparatus 12 to allow for the automatic and dynamic control of gas generation. This is accomplished in general by allowing the reaction chamber pressure P 18 to control the inflow of fluid fuel component 22 using fluid transfer valve 33 and/or one or more pressure-regulating valve 26 , as described below.
[0063] In one embodiment, as shown in FIG. 3 , pressure-regulating valve 26 is positioned in mount 85 or conduits 17 and generally acts as an inlet port between fluid transfer conduit 88 and fluid dispersion element 89 . Pressure-regulating valve 26 can also be positioned in conduit 88 or conduit 15 . An end of fluid dispersion element 89 is connected to a carrier 99 , which is slidably disposed within mount 85 . Near where fluid transfer conduit 17 terminates, one end of carrier 99 is in contact with a globe seal 93 surrounding a jet 94 . Jet 94 is fluidly connected to conduit 17 , and globe seal 93 is configured to control the fluid connection therebetween. As shown in FIG. 3 , valve 26 is in an open configuration, so fluid would be able to flow from fluid transfer conduit 88 into jet 94 .
[0064] The other end of carrier 99 is connected to a pressure actuated system including a diaphragm 96 exposed to reaction chamber 18 and reaction chamber pressure P 18 , a spring 95 biasing diaphragm 96 towards reaction chamber 18 , and a support plate 98 . Carrier 99 is engaged with support plate 98 . Diaphragm 96 may be any type of pressure-sensitive diaphragm known in the art, such as a thin rubber, metal or elastomeric sheet. When reaction chamber pressure P 18 increases due to the production of fuel gas, diaphragm 96 tends to deform and expand toward the base of mount 85 , but is held in place by the force F 95 from spring 95 . When reaction chamber pressure P 18 exceeds the biasing force F 95 provided by spring 95 , diaphragm 96 pushes support plate 98 toward the base of mount 85 . As carrier 99 is engaged with support plate 98 , carrier 99 also moves toward the base of mount 85 . This motion deforms globe seal 93 to seal the connection between fluid transfer conduit 88 and jet 94 , thereby cutting off the flow of fluid fuel component 22 into reaction chamber 18 .
[0065] While valve 33 (shown in FIG. 1 ) is open, the operation of gas-generating apparatus 12 may therefore happen in a dynamic and cyclical fashion to provide on demand fuel to the fuel cell. When valve 33 is initially opened, reaction chamber pressure P 18 is low, so pressure-regulating valve 26 is fully open. Valves 33 and 26 may have substantially similar pressure differentials for opening and closing, and in the preferred embodiment one valve may act as a backup for the other. Alternatively, the opening pressure differentials may be different, i.e., the differential pressure to open or close valve 33 may be higher or lower than that of valve 26 , to provide additional ways to control the flow through conduit 88 .
[0066] As fluid fuel component 22 is fed into reaction chamber via valve 26 and/or valve 33 and fluid dispersal elements 89 , the reaction between fluid fuel component 22 and solid fuel component 24 begins to generate fuel gas. Reaction chamber pressure P 18 gradually increases with the build up of fuel gas until threshold pressure P 34 is reached and valve 34 opens to allow the flow of gas through fuel conduit 16 . Fuel gas is then transferred out of reaction chamber 18 . While this process may reach a steady state, the production of gas may outpace the transfer of gas through valve 34 , or, alternatively, valve 34 or another downstream valve may be manually closed by a user or electronically closed by the fuel cell or host device. In such a situation, reaction chamber pressure P 18 may continue to build until reaction chamber pressure P 18 exceeds the force F 95 supplied by spring 95 . At this point, diaphragm 96 deforms toward the base of mount 85 , thereby driving carrier 99 toward the base of mount 85 . As described above, this action causes globe seal 93 to seal the connection between fluid transfer conduit 88 and jet 94 . As no additional fluid fuel component 22 may be introduced into reaction chamber 18 , the production of fuel gas slows and eventually stops. Valve 33 can also be closed by P 18 , i.e., when P 18 exceeds P 44 or when the difference between P 18 and P 44 is less than a predetermined amount, e.g., the amount of force exerted by spring 35 .
[0067] If valve 34 is still open, or if it is re-opened, fuel gas is then transferred out of reaction chamber 18 , so that reaction chamber pressure P 18 decreases. Eventually, reaction chamber pressure P 18 decreases below the force F 95 provided by spring 95 , which pushes support 98 toward reaction chamber 18 . As support 98 is engaged with carrier 99 , carrier 99 also slides toward reaction chamber 18 , which allows globe seal 93 to return to its unsealed configuration. Consequently, additional fluid fuel component 22 begins to flow through jet 94 and into reaction chamber via fluid dispersal element 89 . New fuel gas is produced, and reaction chamber pressure P 18 rises once again. Similarly, when P 18 is less than P 44 , or is less than P 44 by a predetermined amount, then valve 33 opens to allow fluid fuel component 22 to flow.
[0068] This dynamic operation is summarized below in Table 1, when valve 33 is opened manually, or when valve 33 and valve 26 have substantially the same differential triggering pressure so that one valve backs up the other valve.
[0000]
TABLE 1
Pressure Cycle of Gas-Generating Apparatus
with Valve 33 Open or Omitted
State of Gas
Production, Pressure
Condition of Pressure-
in Reaction Chamber
Pressure Balance
regulating Valve 26
18
P 44 > P 18
OPEN
Gas production starts;
F 95 > P 18
Pressure builds
P 18 < P 34
P 44 ≧ P 18
OPEN
Gas production
F 95 ≧ P 18
continues; Pressure
P 18 = P 34
builds if production
outpaces outflow
P 44 ≦ P 18
CLOSED
Gas production slows
F 95 ≦ P 18
to halt; Pressure
P 18 ≧ P 34
decreases
P 44 > P 18
OPEN
Gas production starts
F 95 > P 18
again
P 18 < P 34
[0000]
TABLE 2
Pressure Cycle of Gas-Generating Apparatus
with Valve 26 Open or Omitted
State of Gas
Production, Pressure
Condition of Pressure-
in Reaction Chamber
Pressure Balance
regulating Valve 33
18
P 44 > P 18
OPEN
Gas production starts;
P 18 < P 34
Pressure builds
P 44 ≧ P 18
OPEN
Gas production
P 18 = P 34
continues; Pressure
builds if production
outpaces outflow
P 44 ≦ P 18
CLOSED
Gas production slows
P 18 ≧ P 34
to halt; Pressure
decreases
P 44 > P 18
OPEN
Gas production starts
P 18 < P 34
again
[0069] Referring to FIGS. 4A and 4B , another suitable pressure regulator or regulating valve 126 is shown. Pressure-regulating valve 126 can be positioned within fluid transfer conduit 88 , similar to the positioning of fluid transfer valve 33 as shown in FIG. 1 . Pressure-regulating valve 126 is preferably placed in series with fluid transfer valve 33 , or pressure-regulating valve 126 may replace fluid transfer valve 33 . Valve 126 can be used with other cartridges or hydrogen generators and can act as a pressure regulator. In another embodiment, regulating valve 126 can replace valve 34 . Regulating valve 126 can be connected to or be a part of the fuel cell or the device that houses the fuel cell. Regulating valve 126 can be located either upstream or downstream of valve components 60 and 62 of connection or shut-off valve 27 .
[0070] Similar to pressure-regulating valve 26 , discussed above, pressure-regulating valve 126 includes a pressure sensitive diaphragm 140 . Diaphragm 140 is similar to diaphragm 96 described above. In this embodiment, however, diaphragm 140 is sandwiched between two housing elements, a valve housing 146 and a valve cover 148 , and has a hole 149 formed through its center, as best seen in FIG. 4A . Additionally, a void 129 is formed at the interface of valve housing 146 and valve cover 148 to allow diaphragm 140 to move or flex due to the pressure difference between the inlet pressure at channel 143 , the outlet pressure at channel 145 , and a reference pressure, P ref . Valve housing 146 has an internal configuration that defines a flow path through regulator valve 126 . Specifically, channels 143 and 145 are formed in valve housing 146 , where channel 143 is exposed to the inlet pressure and channel 145 is exposed to the outlet pressure. Further, a vent channel 141 is formed in valve cover 148 so that diaphragm 140 is exposed to the reference pressure, which may be atmospheric pressure.
[0071] Valve housing channel 143 is configured to slidingly receive a valve stem 142 . Valve housing channel 143 is configured to narrow at or near the interface of valve housing 146 and valve cover 148 to form a shoulder 137 . Valve stem 142 is preferably a unitary element having a slender stem portion 138 and a cap 131 . This configuration allows slender stem portion 138 to extend through the narrow portion of valve housing channel 143 while cap 131 comes to rest against shoulder 137 . As such, cap 131 and shoulder 137 both include sealing surfaces to close the flow path through valve 126 at shoulder 137 when cap 131 is seated thereagainst. Additionally, a grommet 147 secures valve stem 142 within hole 149 in diaphragm 140 , thereby creating a seal and a secure connection between diaphragm 140 and valve stem 142 . Therefore, as diaphragm 140 moves, valve stem 142 also moves such that cap 131 is seated and unseated against shoulder 137 thereby opening and closing valve 126 .
[0072] When pressure-regulating valve 126 is positioned in conduit 88 of gas-generating apparatus 12 , reaction chamber pressure P 18 provides the outlet pressure at channel 145 and reservoir pressure P 44 provides the inlet pressure at channel 143 . When reaction chamber pressure P 18 is low, valve 126 is in an open configuration as shown in FIG. 4A , where diaphragm is unflexed and cap 131 of valve stem 142 is unseated from shoulder 137 . As such, fluid fuel component 22 (shown in FIG. 1 ) flows through valve 126 and into fluid dispersal element 89 (shown in FIG. 1 ), assuming that fluid transfer valve 33 is also open. The introduction of fluid fuel component 22 to solid fuel component 24 starts the production of fuel gas, which seeps through solid fuel container 23 (shown in FIG. 1 ) and into reaction chamber 18 , as described above. Reaction chamber pressure P 18 begins to rise. The pressure within conduit 145 rises with P 18 and translates into void 129 . Reaction chamber pressure P 18 gradually increases with the buildup of fuel gas until threshold pressure P 34 is reached and valve 34 (shown in FIG. 1 ) opens to allow the flow of gas through fuel conduit 16 (shown in FIG. 1 ). Fuel gas is then transferred out of reaction chamber 18 . While this process may reach a steady state, the production of gas may outpace the transfer of gas through valve 34 , or, alternatively, valve 34 or valve 27 may be manually or electronically closed. In such a situation, reaction chamber pressure P 18 may continue to build until reaction chamber pressure P 18 exceeds P ref , P 44 or (P 44 less P ref ) as no further gas is transferred from reaction chamber 18 with valve 34 (or valves 34 , 27 ) closed. As a result of the rising reaction chamber pressure P 18 , diaphragm 140 deforms toward valve cover 148 . If reaction chamber pressure P 18 continues to rise, diaphragm 140 deforms toward valve cover 148 to such an extent that cap 131 of valve stem 142 seats against shoulder 137 to seal valve 126 . As such, the flow of additional fluid fuel component is halted, which slows and eventually stops the production of fuel gas in reaction chamber 18 .
[0073] If valve 34 remains open, fuel gas is transferred out of reaction chamber 18 , which reduces the reaction chamber pressure P 18 . This reduction in reaction chamber pressure P 18 is transferred to void 129 by conduit 145 , and diaphragm 140 starts to return to its original configuration as the pressure differential thereacross begins to equalize, i.e., P 18 , P 44 and P ref begin to balance. As diaphragm 140 moves back into position, valve stem 142 is also moved, thereby unseating cap 131 from shoulder 137 to re-open valve 126 . As such, fluid fuel component 22 is free to once again flow into reaction chamber 18 . This cycle, which is similar to the cycle described in Table 1, repeats until fluid transfer valve 33 , fuel transfer valve 34 , or another downstream valve is closed by the operator or controller.
[0074] The pressure at which regulator/valve 126 opens or closes can be adjusted by adjusting the length of the valve stem or the gap that cap 131 travels between the open and closed position and/or by adjusting P ref . Stem 138 is sized and dimensioned to be movable relative to grommet 147 to adjust length of stem 138 . The longer the length of stem 138 between grommet 147 and cap 131 , the higher the pressure needed to close valve 126 .
[0075] In the embodiment where pressure-regulating valve 126 is located downstream of reaction chamber 18 , e.g., when valve 126 replaces valve 34 or when valve 126 is connected to the fuel cell or the device that houses the fuel cell, P 18 becomes the inlet pressure at channel 143 and the outlet pressure at channel 145 is the pressure of the hydrogen fuel gas that the fuel cell would receive. Preferably, the outlet pressure is substantially constant or is kept within an acceptable range, and the reference pressure, P ref , is selected or adjusted to provide such an outlet pressure. In other words, P ref is set so that when the inlet pressure exceeds a predetermined amount, diaphragm 140 closes to minimize high or fluctuating outlet pressure at channel 145 .
[0076] Another embodiment of a pressure-regulating valve 226 is shown in FIGS. 4C and 4D . Pressure-regulating valve 226 is similar to pressure-regulating valve 126 discussed above, as a valve housing 248 is attached to a valve cap 247 . Formed in valve cap 247 is an inlet 243 , while a pressure regulated outlet 245 is formed in valve housing 248 . A hole 251 is formed in a lower portion of valve cap 247 . Preferably, hole 251 is slightly off-center from the longitudinal axis of pressure-regulating valve 226 .
[0077] Sandwiched and retained between valve cap 247 and valve housing 248 is a deformable capped cylinder 250 . Capped cylinder 250 includes an upper end 259 , a lower end 287 , and a hole or channel 201 formed therethrough. Capped cylinder 250 is made of any deformable, elastomeric material known in the art, such as rubber, urethane, or silicone. Capped cylinder 250 functions similar to a pressure-sensitive diaphragm.
[0078] Upper end 259 is positioned adjacent valve cap 247 such that when no fluid flows through pressure-regulating valve 226 upper end 259 is flush against a lower surface of valve cap 247 . The edges of upper end 259 are fixed in position so that even if the remainder of upper cap 259 flexes, the edges remain stationary and sealed.
[0079] Lower end 287 is positioned adjacent valve housing 248 . A void 202 is formed in valve housing 248 and is positioned directly below lower end 287 to allow lower end 287 to flex freely. Preferably, lower end 287 has a different diameter than upper end 259 , as explained below.
[0080] A retainer 253 made of a substantially rigid material surrounds capped cylinder 250 . Retainer 253 defines a hole 241 to connect a second void 203 formed circumferentially between capped cylinder 250 and retainer 253 with a reference pressure P ref . Portion 205 of second void 203 is configured to extend partially along and on top of lower cap 287 .
[0081] To regulate pressure, inlet gas or liquid enters pressure-regulating valve through inlet 243 and passes into hole 251 . Hole 251 can be a circular channel or ring defined on cap 247 . Upper end 259 seals hole 251 until the pressure exerted by the inlet gas or liquid from inlet 243 reaches a threshold to deform upper end 259 . When the gas deforms upper end 259 , the deformation translates through the body of cylinder 250 to also deform lower end 287 . Once upper end 259 deforms, the gas is able to pass through hole 251 , through capped cylinder 250 and out regulated outlet 245 .
[0082] Since the applied forces on capped cylinder 250 are the products of the applied pressure times the area exposed to that pressure, the forces acting on capped cylinder 250 can be summarized as follows:
[0000] Inlet Force+Reference Force Outlet Force
[0000] ( P at inlet 243 ·Area of upper end 259 )+( Pref ·Area of portion 205 )←→( P at outlet 245 ·Area of lower end 287 )
[0000] When the outlet force is greater than the inlet and reference forces, then pressure-regulating valve 226 is closed, and when outlet force is less than the inlet and reference forces, the valve 226 is open. Since, in this embodiment the outlet force has to counter-balance both the inlet and reference forces, the area of lower end 287 is advantageously made larger than the area of upper end 259 , as shown, so that the outlet force may be larger without increasing the outlet pressure. By varying the areas of ends 259 and 287 and portion 205 , the balance of forces on capped cylinder 250 can be controlled and the pressure differential required to open and close valve 226 can be determined.
[0083] Since reference pressure P ref tends to press down on lower end 287 , this additional pressure can lower the threshold pressure to initiate flow, i.e., reference pressure P ref is relatively high to assist the gas in deforming capped cylinder 250 . Reference pressure P ref may be adjusted higher or lower to further regulate the pressure of the gas leaving outlet 245 .
[0084] FIGS. 5A-D shows a combination of a pressure-regulating valve 326 being used with connection or shut-off valve 27 . FIG. 5A shows pressure-regulating valve 326 being mated to be in fluid communication with valve component 60 of connection valve 27 . Pressure-regulating valve 326 is similar to pressure-regulating valves 126 and 226 described above, and has a spring-biased diaphragm 340 . Diaphragm 340 is supported by first piston 305 , which is being biased by spring 306 toward second piston 307 . First piston 305 is opposed by second piston 307 biased by spring 309 , which biases piston 307 toward piston 305 . A ball 311 is disposed between spring 309 and second piston 307 .
[0085] Springs 306 and 309 oppose each other, and, by balancing the forces exerted by the two springs, the outlet pressure at channel 313 can be determined. Spring 309 does not act on or have any effect on spring 66 of valve component 60 . When valve component 60 is opened by mating with valve component 62 , shown in FIGS. 5B-5D , hydrogen fuel gas or other fluids flows through valve component 60 and to inlet 315 . If the fluid is hydrogen gas, then the hydrogen is transported to the fuel cell. A flow path through valve 326 is established from inlet 315 through spring 309 , around ball 311 , through the space between piston 307 and shoulder 337 of housing 346 , though orifice 337 of housing 346 , and through orifice 348 and outlet 313 . In this embodiment, the space between piston 307 and shoulder 337 is normally open to allow fluid to pass therethrough.
[0086] The pressure of the incoming fluid through inlet 315 or the pressure at outlet 313 , if sufficiently high, may overcome the resultant force between springs 306 and 309 and move diaphragm 340 and pistons 305 and 307 to the left as depicted in FIG. 5A . Spring 309 then biases ball 311 to sealing member 319 to seal valve 326 . To ensure that the flow of fuel follows the preferred path, sealing member 317 may be provided.
[0087] In one embodiment, the force applied on diaphragm 340 and pistons 305 and 307 can be adjusted. Spring 306 is adjustable by a rotational adjusting member 321 , which is secured by a threaded lock nut 321 . Rotating adjusting member 321 in one direction further compresses spring 306 to increase the force applied on the diaphragm and pistons, and rotating in the opposite direction expands spring 306 to decrease the force applied on the diaphragm and pistons. Additionally, a reference pressure, P ref , can be applied to channel 323 behind piston 305 to apply another force on piston 305 .
[0088] FIG. 5B shows pressure regulator/valve 326 connected to valve component 60 with valve component 62 not connected to valve component 60 . FIG. 5C shows regulator/valve 326 with valve components 60 and 62 partially engaged, but with no flow path established through valve components 60 and 62 . FIG. 5D shows regulator/valve 326 with valve components 60 and 62 fully engaged with a flow path established through valve components 60 and 62 . In one embodiment, valve component 62 may be connected to conduit 16 of gas-generating apparatus 12 , shown in FIG. 1 , and regulator 326 replaces valve 34 and is connected to the fuel cell or the device. On the other hand, valve component 62 may be connected to the fuel cell or the device and regulator 326 and valve component 60 are connected to the gas-generating apparatus or fuel supply. If a high pressure surges through valve 326 , diaphragm 340 limits the amount of fuel that can be transported through conduit 313 .
[0089] Another embodiment of a pressure-regulating valve 426 is shown in FIGS. 6A and B. Pressure-regulating valve 426 is similar to pressure-regulating valve 226 , discussed above, except that valve 426 has a slidable piston 450 instead of flexible capped cylinder 250 . Valve 426 has valve housing 448 attached to a valve cap 447 . Formed in valve cap 447 is an inlet 443 , while a pressure regulated outlet 445 is formed in valve housing 448 . A hole 451 is formed in a lower portion of valve cap 447 . Preferably, hole 451 is slightly off-center from the longitudinal axis of pressure-regulating valve 426 . Hole 451 may comprise a plurality of holes formed as a ring so that the inlet pressure is applied uniformly on slidable piston 450 .
[0090] Slidably disposed between valve cap 447 and valve housing 448 is a slidable piston 450 . Slidable piston 450 includes an upper portion 459 having a first diameter, a lower portion 487 having a second diameter which is preferably larger than the diameter of upper portion 459 , and a hole 401 formed therethrough. Slidable piston 450 is made of any rigid material known in the art, such as plastic, elastomer, aluminum, a combination of elastomer and a rigid material or the like.
[0091] A space 402 is formed in valve housing 448 to allow piston 450 to slide between cap 447 and housing 448 . A second void 403 is formed between slidable piston 450 and valve housing 448 . Void 403 is connected with a reference pressure P ref . A portion 405 of void 403 is positioned opposite to lower end 487 , so that a reference force can be applied on piston 450 .
[0092] Upper portion 459 is positioned adjacent valve cap 447 such that when the outlet force exceeds the inlet force and the reference force, as discussed above, upper portion 459 is flush against a lower surface of valve cap 447 to close valve 426 , as shown in FIG. 6A . When the outlet force is less than the inlet and reference forces, piston 450 is pushed toward housing 448 to allow fluids, such as hydrogen gas, to flow from inlet 443 through hole(s) 451 and hole 401 to outlet 445 . Again, as discussed above with reference to valve 226 , the surface areas of ends 459 and 487 , and of space 405 can be varied to control the opening and closing of valve 426 .
[0093] As will be recognized by those in the art, any of these valves may be used, either alone or in combination, to provide pressure-based regulation of gas-generating apparatus 12 . For example, valve 126 , 226 , 326 or 426 can be used in place of valve 26 , 33 or 34 .
[0094] In accordance to another aspect of the present invention, a pre-selected orifice is provided in conjunction with valve 126 , 226 , 326 and/or 426 to regulate the pressure or volume of the fluid, e.g., hydrogen gas, exiting from the outlet of these valves. For example, referring to valve 326 , shown in FIG. 5A , orifice 348 is positioned upstream of outlet 313 . In one aspect, orifice 326 acts as a flow restrictor to ensure that when the inlet pressure at inlet 315 or within pressure-regulating valve 326 is high, orifice 348 sufficiently limits the outlet flow at 313 so that the high pressure can act on diaphragm 340 , moving it to the left, to close valve 326 . An advantage of using flow restrictor/orifice 348 is when outlet 313 is open to a low pressure, e.g., atmospheric pressure, or open to a chamber that cannot hold pressure orifice 348 helps ensure that diaphragm 340 would sense the inlet pressure.
[0095] Orifice 348 may also control the flow of fluid out of outlet 313 . When the range of inlet pressure at inlet 315 or pressure internal to pressure-regulating valve 326 is known and the desirable flow rate is also known, by applying flow equations for compressible fluid flow, such as Bernoulli's equations (or using incompressible fluid flow equations as a close approximation thereof) the diameter(s) of orifice 348 can be determined.
[0096] Additionally, the diameter of effective diameter of orifice 348 may vary according to inlet pressure at inlet 315 or internal pressure of valve 326 . One such variable orifice is described in commonly owned, co-pending U.S. Publ. Appl. No. US 2005/0118468, which is incorporated herein by reference in its entirety. The '468 reference discloses valve ( 252 ) shown in FIGS. 6( a )-( d ) and 7 ( a )-( k ) and corresponding texts of that reference. The various embodiments of this valve ( 252 ) have reduced effective diameter when flow pressure is high and have increased effective diameter when the flow pressure is lower.
[0097] Another variable orifice 348 is shown in FIGS. 7A and 7B . In this embodiment, orifice 348 or another fluid conduit has a duckbill valve 350 disposed therein with nozzle 352 facing the direction of fluid flow, as shown. The fluid's pressure acts on neck 354 and when the pressure is relatively low the diameter of nozzle 352 is relatively large, and when the pressure is relatively high the diameter of nozzle 352 is relatively small to further restrict flow. When pressure is sufficiently high, nozzle 352 may be shut off.
[0098] Some examples of the fuels that are used in the present invention include, but are not limited to, hydrides of elements of Groups IA-IVA of the Periodic Table of the Elements and mixtures thereof, such as alkaline or alkali metal hydrides, or mixtures thereof. Other compounds, such as alkali metal-aluminum hydrides (alanates) and alkali metal borohydrides may also be employed. More specific examples of metal hydrides include, but are not limited to, lithium hydride, lithium aluminum hydride, lithium borohydride, sodium hydride, sodium borohydride, potassium hydride, potassium borohydride, magnesium hydride, calcium hydride, and salts and/or derivatives thereof. The preferred hydrides are sodium borohydride, magnesium borohydride, lithium borohydride, and potassium borohydride. Preferably, the hydrogen-bearing fuel comprises the solid form of NaBH 4 , Mg(BH 4 ) 2 , or methanol clathrate compound (MCC) which is a solid and includes methanol. In solid form, NaBH 4 does not hydrolyze in the absence of water and therefore improves shelf life of the cartridge. However, the aqueous form of hydrogen-bearing fuel, such as aqueous NaBH 4 , can also be utilized in the present invention. When an aqueous form of NaBH 4 is utilized, the chamber containing the aqueous NaBH 4 also includes a stabilizer. Exemplary stabilizers can include, but are not limited to, metals and metal hydroxides, such as alkali metal hydroxides. Examples of such stabilizers are described in U.S. Pat. No. 6,683,025, which is incorporated by reference herein in its entirety. Preferably, the stabilizer is NaOH.
[0099] The solid form of the hydrogen-bearing fuel is preferred over the liquid form. In general, solid fuels are more advantageous than liquid fuels because the liquid fuels contain proportionally less energy than the solid fuels and the liquid fuels are less stable than the counterpart solid fuels. Accordingly, the most preferred fuel for the present invention is powdered or agglomerated powder sodium borohydride.
[0100] According to the present invention, the fluid fuel component preferably is capable of reacting with a hydrogen-bearing solid fuel component in the presence of an optional catalyst to generate hydrogen. Preferably, the fluid fuel component includes, but is not limited to, water, alcohols, and/or dilute acids. The most common source of fluid fuel component is water. As indicated above and in the formulation below, water may react with a hydrogen-bearing fuel, such as NaBH 4 in the presence of an optional catalyst to generate hydrogen.
[0000] X(BH 4 ) y +2H 2 O→X(BO) 2 +4H 2
[0000] Where X includes, but is not limited to, Na, Mg, Li and all alkaline metals, and y is an integer.
[0101] Fluid fuel component also includes optional additives that reduce or increase the pH of the solution. The pH of fluid fuel component can be used to determine the speed at which hydrogen is produced. For example, additives that reduce the pH of fluid fuel component result in a higher rate of hydrogen generation. Such additives include, but are not limited to, acids, such as acetic acid and sulfuric acid. Conversely, additives that raise the pH can lower the reaction rate to the point where almost no hydrogen evolves. The solution of the present invention can have any pH value less than 7, such as a pH of from about 1 to about 6 and, preferably, from about 3 to about 5.
[0102] In some exemplary embodiments, fluid fuel component includes a catalyst that can initiate and/or facilitate the production of hydrogen gas by increasing the rate at which fluid fuel component reacts with a fuel component. The catalyst of these exemplary embodiments includes any shape or size that is capable of promoting the desired reaction. For example, the catalyst may be small enough to form a powder or it may be as large as the reaction chamber, depending on the desired surface area of the catalyst. In some exemplary embodiments, the catalyst is a catalyst bed. The catalyst may be located inside the reaction chamber or proximate to the reaction chamber, as long as at least one of either fluid fuel component or the solid fuel component comes into contact with the catalyst.
[0103] The catalyst of the present invention may include one or more transitional metals from Group VIIIB of the Periodic Table of Elements. For example, the catalyst may include transitional metals such as iron (Fe), cobalt (Co), nickel (Ni), ruthenium (Ru), rhodium (Rh), platinum (Pt), palladium (Pd), osmium (Os) and iridium (Ir). Additionally, transitional metals in Group IB, i.e., copper (Cu), silver (Ag) and gold (Au), and in Group IIB, i.e., zinc (Zn), cadmium (Cd) and mercury (Hg), may also be used in the catalyst of the present invention. The catalyst may also include other transitional metals including, but not limited to, scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr) and manganese (Mn). Transition metal catalysts useful in the present invention are described in U.S. Pat. No. 5,804,329, which is incorporated by reference herein in its entirety. The preferred catalyst of the present invention is CoCl 2 .
[0104] Some of the catalysts of the present invention can generically be defined by the following formula:
[0000] M a X b
[0105] wherein M is the cation of the transition metal, X is the anion, and “a” and “b” are integers from 1 to 6 as needed to balance the charges of the transition metal complex.
[0106] Suitable cations of the transitional metals include, but are not limited to, iron (II) (Fe 2+ , iron (III) (Fe 3+ ), cobalt (Co 2+ ), nickel (II) (Ni 2+ ), nickel (III) (Ni 3+ ), ruthenium (III) (Ru 3+ ), ruthenium (IV) (Ru 4+ ), ruthenium (V) (Ru 5+ ), ruthenium (VI) (Ru 6+ ), ruthenium (VIII) (Ru 8+ ), rhodium (III) (Rh 3 ), rhodium (IV) (Rh 4+ ), rhodium (VI) (Rh 6+ ), palladium (Pd 2+ ), osmium (III) (Os 3+ ), osmium (IV) (OS 4+ ), osmium (V) (OS 5+ ), osmium (VI) (Os 6+ ), osmium (VIII) (Os 8+ ), iridium (III) (Ir 3+ ), iridium (IV) (Ir 4+ ), iridium (VI) (Ir 6+ ), platinum (II) (Pt 2+ ), platinum (III) (Pt 3+ ), platinum (IV) (Pt 4+ ), platinum (VI) (Pt 6+ ), copper (I) (Cue), copper (II) (Cu 2+ ), silver (I) (Ag + ), silver (II) (Ag 2+ ), gold (I) (Au + ), gold (III) (Au 3+ ), zinc (Zn 2+ ), cadmium (Cd 2+ ), mercury (I) (Hg + ), mercury (II) (Hg 2+ ), and the like.
[0107] Suitable anions include, but are not limited to, hydride (H − ), fluoride (F − ), chloride (Cl − ), bromide (Br − ), iodide (I − ), oxide (O 2− ), sulfide (S 2− ), nitride (N 3− ), phosphide (P 4− ), hypochlorite (ClO − ), chlorite (ClO 2 − ), chlorate (ClO 3 − ), perchlorate (ClO 4 − ), sulfite (SO 3 2− ), sulfate (SO 4 2− ), hydrogen sulfate (HSO 4 − ), hydroxide (OH − ), cyanide (CN − ), thiocyanate (SCN − ), cyanate (OCN − ), peroxide (O 2 2− ), manganate (MnO 4 2− ), permanganate (MnO 4 − ), dichromate (Cr 2 O 7 2− ), carbonate (CO 3 2− ), hydrogen carbonate (HCO 3 − ), phosphate (PO 4 2− ), hydrogen phosphate (HPO 4 − ), dihydrogen phosphate (H 2 PO 4− ), aluminate (Al 2 O 4 2− ), arsenate (AsO 4 3− ), nitrate (NO 3 − ), acetate (CH 3 COO − ), oxalate (C 2 O 4 2− ), and the like. A preferred catalyst is cobalt chloride.
[0108] In some exemplary embodiments, the optional additive, which is in fluid fuel component and/or in the reaction chamber, is any composition that is capable of substantially preventing the freezing of or reducing the freezing point of fluid fuel component and/or solid fuel component. In some exemplary embodiments, the additive can be an alcohol-based composition, such as an anti-freezing agent. Preferably, the additive of the present invention is CH 3 OH. However, as stated above, any additive capable of reducing the freezing point of fluid fuel component and/or solid fuel component may be used.
[0109] Other embodiments of the present invention will be apparent to those skilled in the art from consideration of the present specification and practice of the present invention disclosed herein. For example, any of the valves herein may be triggered by an electronic controller such as a microprocessor. A component of one valve can be used with another valve. Also, a pump may be included to pump the fluid fuel component into the reaction chamber. It is intended that the present specification and examples be considered as exemplary only with a true scope and spirit of the invention being indicated by the following claims and equivalents thereof.
|
The present application is directed to a gas-generating apparatus and various pressure regulators or pressure-regulating valves. Hydrogen is generated within the gas-generating apparatus and is transported to a fuel cell. The transportation of a first fuel component to a second fuel component to generate of hydrogen occurs automatically depending on the pressure of a reaction chamber within the gas-generating apparatus. The pressure regulators and flow orifices are provided to regulate the hydrogen pressure and to minimize the fluctuation in pressure of the hydrogen received by the fuel cell. Connecting valves to connect the gas-generating apparatus to the fuel cell are also provided.
| 8
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to H 3 PO 4 /CrO 3 coating baths for metal surfaces, and in particular to a method for extending the useful life of known H 3 PO 4 /CrO 3 coating baths and to a method of applying chromium phosphate coatings.
2. Statement of the Related Art
In order to deposit high-weight chromium phosphate coatings on metal surfaces (e.g., more than about 300 mg/ft 2 or about 3.24 g/m 2 ) active coating baths are employed to treat the substrate, causing high levels of displaced metal ions to build up rapidly in the bath. Since the presence of these ions in excess results in loose, powdery coatings, the baths must be discarded and renewed at frequent intervals, which is expensive and also creates waste disposal problems. A particular problem is presented by zinc-bonded aluminum surfaces of the type prepared by processes such as the ALFUSE process, (trademark of Modine Mfg. Corp., Racine, Wisc., U.S.A.) in which high zinc deposition ratios are employed. The use of an active H 3 PO 4 /CrO 3 coating bath on these substrates results in high levels of dissolved Zn and Al in the bath, which interfere with the coating process and rapidly decrease the useful life of the bath. Although replenishers for renewing H 3 PO 4 /CrO 3 baths are commercially available, such prior art replenishers characteristically have CrO 3 and H 3 PO 4 ratios comparable to fresh bath ratios; as a result, the useful life of baths replenished with these materials is not usually remarkably extended.
DESCRIPTION OF THE INVENTION
This invention relates to a method for replenishing used H 3 PO 4 CrO 3 coating baths employed in the production of chromium phosphate coatings on aluminum surfaces, especially zinc bonded aluminum surfaces and to a method of applying the chromium phosphate coatings. It has been found that increasing the relative CrO 3 (hexavalent chromium or Cr VI ) content of the used coating bath effectively counteracts the tendency of the chromium phosphate coatings to become loose and powdery as the dissolved aluminum content of the bath increases over time. The concept is particularly applicable to aluminum metal surfaces coated with zinc or similar metals, especially those produced by deposition of zinc from a zinc chloride flux onto an aluminum surface such as that produced by the above mentioned ALFUSE process.
According to the present invention, the metal substrate is treated with a conventional H 3 PO 4 /CrO 3 coating bath. Such baths typically contain a mole ratio of H 3 PO 4 to CrO 3 of about 2.5-3.0:1, preferably about 2.80-2.90:1, and have a usual hydrofluoric acid content of about 0.5 to about 2.0 grams per liter. Exemplary commercial replenisher formulations for these baths include ALODINE® 401, 405, 406 and 407, (proprietary compositions of Amchem Products, Inc., Ambler, Pa., U.S.A.), which contain representative mole ratios of H 3 PO 4 to CrO 3 of about 2.90:1.0 at concentrations of H 3 PO 4 and CrO 3 of about 650 g/l (grams/liter) and 225 g/l, respectively. Coating baths containing about 28 g/l H 3 PO 4 and about 10 g/l CrO 3 are typically prepared by appropriate dilution of these replenisher formulations, usually to about 4-5% by volume. HF is then added to activate the bath sufficiently to obtain coatings of the desired weight on the metal substrate.
As previously noted, coating weights in excess of about 300 mg/ft 2 require an active bath, wherein dissolved metal from the substrate rapidly builds up in the bath. Generally at a dissolved metal content above about 10 g/l, reaction products in these coating baths, especially dissolved aluminum and zinc, begin to promote loose and powdery coatings. At this point, conventional baths are considered to be exhausted, and are discarded. It has unexpectedly been discovered, however, that replenishment of these coating baths with a replenisher composition having an unusually high relative CrO 3 content markedly extends the useful life of the bath. While the present concept is particularly applicable to coating processes adapted to produce relatively heavy coatings of from about 300-450 mg/ft 2 , the concept is broadly applicable to processes for producing a chromium phosphate coating having a weight of from about 5 to 600 mg/ft 2 . (0.054 to 6.48 g/m 2 ).
In accordance with the present invention, the CrO 3 content of a used coating bath is increased at least about sufficiently to restore the bath to at least its original CrO 3 concentration usually of about 10 g/l and preferably up to about 150% of its original concentration usually of about 15 g/l, while maintaining the H 3 PO 4 content of the bath substantially constant. Surprisingly, the adverse effects of the high metal ion content of the bath are thus effectively counteracted, and a two-to threefold increase in bath life is usual. The addition can be repeated as required, until no longer effective.
The CrO 3 content of the coating bath can be gradually replenished or increased on a continuing basis or an appropriate amount of CrO 3 may be repeatedly added batchwise as the bath nears exhaustion. Exhausted baths are characterized by the production of loose and powdery coatings, attributable to an excessive dissolved metal content. Dissolved metal content can be conveniently monitored by determination of the Cr III content by known methods. While particular systems will vary, a bath concentration of CR III of about 1/3 of starting Cr VI concentration generally signifies imminent bath exhaustion, and the bath should be renewed at or before this point. Exhaustion of the bath is also characterized by decreasing bath efficiency (wt. dissolved metal/wt. of coating produced). Generally, as the bath deteriorates, the weight of dissolved metal increases and, also, the coating weight decreases, with significant concomitant losses in coating efficiency. Increasing the hexavalent chromium concentration of a used bath according to the present invention not only yields tight coatings at relatively high dissolved metal concentrations (e.g., 20 or more g/l dissolved metal), but also significantly improves bath efficiency, as will be shown in the examples which follow. To restore the coating baths according to the invention, a sufficient amount of CrO 3 is added to the used bath to restore the Cr VI content thereof to at least about the levels present in the fresh bath; a typical bath containing about 10 g/l of CrO 3 when fresh will require an increase in concentration of at least about 0.034 moles CrO 3 near the exhaustion point to restore bath efficiency, if the exhaustion point is taken as the point wherein about 1/3 of Cr VI has been reduced.
To achieve this end, replenishers having a mole ratio of H 3 PO 4 to CrO 3 substantially lower than the comparable ratios in prior art make-up and replenishers are conveniently employed. Replenishers having a H 3 PO 4 to CrO 3 mole ratio of about 1.10 to 1.25:1 are suitable, and those having a mole ratio (H 3 PO 4 :CrO 3 ) of about 1.13 to 1.18:1 are particularly suitable. Such replenishers contrast sharply with prior art replenishers having characteristic H 3 PO 4 :CrO 3 ratios in excess of 2.80:1.
The following Examples are illustrative of the practice of the invention.
EXAMPLES
A.
Methods
1. Cr III Determination: RT-AT v. Total Aluminum Dissolved.
RT is "Reaction Titration" (total Cr +6 and Cr +3 ) and AT is "Alodine® Titration" (Cr +6 titration). To monitor dissolved aluminum, Cr +3 is oxidized and then titrated as Cr +6 by known methods. The difference (RT-AT) represents the amount of Cr +3 present in the used bath, which is a measure of the amount of dissolved (oxidized) metal present. The amount of Cr +3 in the bath is easily determined by this titration and provides a quick method for determination of dissolved metal, by calculation against a standard (RT-AT v. total metal dissolved). In an exemplary application: a fresh bath with no metal dissolved contains 10 g CrO 3 per liter (0.1 mole); for this bath, 15 mL 0.1N thiosulfate is required to starch endpoint on a iodimetric titration using a 5 mL aliquot. When the used bath attains an RT-AT value of 20RT-15AT=5.0, by calculation to standard approximately 11.5 g per liter of dissolved metal as aluminum and zinc is present in the bath, and loose coatings are almost certain in baths formulated for 300 to 400 mg per sq.ft. of coating weight. An RT-AT of 5.0 in this system calculates as 3.34 g/L of reduced CrO 3 , or 0.034 moles. A new bath adjustment is required by the time the reduced CrO 3 (Cr +3 ) reaches 1/3 of the concentration of the original hexavalent Cr content.
2. Bath Efficiency Determination
As coatings are formed, some metal dissolves from the surface of the substrate parts. The efficiency of the bath is determined by comparing the initial weight of a substrate part with the coated and stripped substrate part weights. The part is weighed and processed through the bath; the coated weight of the part is noted, the coating is then stripped, and the stripped weight of the part noted. For an example, in a 4"×6" aluminum panel:
(1) Initial Wt.=24.8755 g
(2) Coated Wt.=24.9719 g
(3) Stripped Wt.=24.8333 g
Bath efficiency is defined herein as the weight of metal dissolved per unit of coating weight produced, and calculated as follows:
Initial wt. less stripped wt.=metal dissolved
Coated wt. less stripped wt.=coating wt.
In this case No. 1-No. 3 is the metal dissolved, or 42.2 mg. The coating weight is calculated from No. 2-No. 3 as 138.6 mg of coating produced on this panel. Then, ##EQU1##
An increase in the calculated efficiency value reflects a decrease in the efficiency of the bath.
For example, the same bath which has reached exhaustion may have the following exemplary efficiency:
(1) Initial Wt. of aluminum part: 24.5290 g
(2) Coated Wt. of aluminum part: 24.5990 g
(3) Stripped Wt. of aluminum part: 24.4690 g
(Employing comparable 4"×6" aluminum panels). The bath efficiency is ##EQU2## Thus, for each gram of coating produced, 0.461 grams of aluminum is being dissolved into the bath with equivalent reduction of Cr VI to Cr III . Note that both the dissolved metal value has increased and coating weight values have decreased over the comparable values in the preceding calculation, indicating that both increased metal content and decreased coating weight may result from bath exhaustion, and that either or usually both these phenomena may contribute to decreased bath efficiency. (It is noted that coating weights are usually expressed in weight per sq. ft. of surface; since the surface area is constant in these determinations, this parameter is omitted. As the test panels have a surface area of 1/3 sq. ft., coating weights in mg/ft 2 are here obtained by multiplying coating weight in mg. by 3.)
EX. I
Replenisher Formulation
A replenisher is prepared as follows:
350 g CrO 3 and 330 ml 75% H 3 PO 4 are combined with water to a total volume of 1 liter.
The H 3 PO 4 :CrO 3 mole ratio is 3.987:3.5=1.139:1 (350 g CrO 3/1 and 390.72 g H 3 PO 4/1 ).
EX. II
Replenisher Formulation
A replenisher is prepared as follows:
327 g CrO 3 is admixed with 325 mL 75% H 3 PO 4 , and H 2 O to a total volume of 1 liter.
The H 3 PO 4 :CrO 3 mol ratio is 1.20:1 (327 g CrO 3/ l and 386.9 g H 3 PO 4/ l).
EX. III
Coating Process According to Invention
A field trial was conducted on a prior art bath close to exhaustion. The CrO 3 content of this bath was increased by 3.34 g per liter or 0.034 moles to a Cr O 3 concentration of 13.34 g/l from the original concentration by addition of CrO 3 . Table 1 below shows the results of this increase in hexavalent chromium while holding H 3 PO 4 and HF constant.
TABLE 1______________________________________Value Before Adjustment 1/2 hr After Adjustment______________________________________AT (sodium 14.3 19.4thiosulphate)(ml)RT (ml) 21.1 26.4RT-AT (ml) 6.8 7.0Zinc (g/l) 7.25 7.20Aluminum (g/l) 7.55 7.40Initial Wt. (g) 25.6434 24.5290Coated Wt. (g) 25.7210 24.6230Stripped Wt. (g) 25.5791 24.4738Efficiency 0.453 0.368Coating Wt. 425.7 448.8(mg/ft.sup.2)______________________________________
Note the improvement in bath efficiency and increase in coating weight. After the first adjustment, this bath was replenished with replenisher according to Example I for two more days with continued success until one 55 gallon drum was used. Subsequent efficiencies over the course of this one 55 gallon drum of replenishment were 0.347, 0.357, 0.365, 0.371 and 0.380. At termination, the bath contained 9.85 g zinc and 11.5 g aluminum per liter or a total of 21.4 g of metal. Prior baths could only tolerate about 12 or 13 g/l of dissolved metal before producing loose coatings. (cf. Ex. V).
The following table shows the laboratory titrations, including free acid (F.A.) and total acid (T.A.). The free acid values indicate that the reduced phosphoric acid in the replenisher employed was at a high enough concentration to keep the free acid at a constant level.
TABLE 2__________________________________________________________________________Sample g/lNo. Time Comment AT RT RT - AT FA TA pH Zn Al Metal Efficiency__________________________________________________________________________1 Wed. Table/bath 14.3 21.1 6.8 2.3 8.4 1.54 7.25 7.55 14.80 0.453 0700 before adjustment2 Wed. Add 3.34 19.4 26.4 7.0 2.4 8.7 1.54 7.20 7.40 14.60 0.368 0730 g CrO.sub.3 /L3 Wed. Adding 21.8 30.0 8.2 2.5 9.3 1.40 8.15 9.55 17.70 0.357 1500 Ex. I Replenisher4 Thurs. End of addn. 24.1 35.8 11.7 2.5 10.5 1.52 9.30 10.95 20.25 0.365 1000 of Ex. I Replenisher5 Thurs. No 22.3 34.5 12.2 2.5 10.5 1.58 9.85 11.55 21.40 0.371 1330 Additions6 Thurs. Discard 21.7 34.5 13.0 2.5 10.6 1.63 10.30 12.10 22.40 0.368 1500__________________________________________________________________________
The run ended at Thurs. 1500, at which time the bath was discarded. Note the F.A. remained constant, which indicates sufficient H 3 PO 4 . No. 2 had 0.368 efficiency after CrO 3 addition; thereafter efficiency slightly decreased from 0.357 to 0.368 at discard time.
No partial bath stabilization was done. In typical prior art systems, 20% of the bath is discarded at noon and 30% at 3 p.m. of each day of operation to stabilize the bath and prolong useful life. The present invention thus saves on make-up chemical, and expense of disposing of discarded bath.
EX. IV
Coating Process According to Invention
A comparable field test was run with the replenisher of Ex. II, a diluted version of the replenisher employed in Ex. III. As a comparison with the bath composition used in Example V below, the bath ran for a week without stabilization. The metal content of the bath rose to 16 g/l zinc and 16 g/l aluminum with a RT-AT value of 15 mL without producing powdery coatings and while maintaining a bath efficiency below 0.45. In this same amount of time, twice the volume of a conventional bath would have been dumped via bath stabilization (i.e., discard of bath and replenishment with equal volume of prior art replenisher).
EX. V
Comparison Example--Prior Art Coating Process
The following data represents a prior art field run. A commercial bath (28 g/l H 3 PO 4 , 10 g/l CrO 3 ) was monitored from start to finish. The typical buildup of aluminum and zinc is shown in the following chart. Analysis via atomic absorption on the samples taken at 8 a.m., noon, and 3 p.m. are presented. At 3 p.m., a portion of the bath was discarded, and water and an additional quantity of the above commercial bath (mole ratio of CrO 3 :H 3 PO 4 of 1.0:2.89; 227 g/l CrO 3 , 645 g/l H 3 PO 4 ) were added to reduce the dissolved metal (Al+Zn) content for the next day's run.
TABLE 3______________________________________Concentration in ppmDAY TIME ZINC ALUMINUM METAL______________________________________1 8 a.m. 1 0 1 Noon 1097 591 1688 3 p.m. 2050 1131 31812 8 a.m. 1750 981 2731 Noon 1825 1016 3 p.m. 1902 1151 30533 8 a.m. 1618 909 Noon 2267 1371 3 p.m. 2534 1576 41104 8 a.m. 2257 1470 Noon 2680 2040 3 p.m. 3738 2576 63145 8 a.m. 3012 1996 Noon 4012 2782 3 p.m. 4655 3359 80146 8 a.m. 3881 2660 Noon 4741 3255 3 p.m. 5283 3583 88667 8 a.m. 4351 2974 Noon 5189 3491 3 p.m. 5771 3827 95988 8 a.m. 4586 3064 Noon 5243 3563 3 p.m. 5786 3892 96789 8 a.m. 4619 3117 Noon 5333 3493 3 p.m. 5991 3875 986610 8 a.m. 4881 3249 Noon 5643 3768 3 p.m. 6571 4032 10,603______________________________________
As is apparent, even with daily bath stabilization, the total dissolved metal content reached 10.6 g/l. At this time loose coatings were persistent and the total bath as discharged to treatment and disposal.
|
The life of chromium phosphate coating baths is extended by at least fully restoring depleted Cr VI ; bath efficiencies are significantly improved.
| 2
|
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/664,518 filed Sep. 17, 2003, this application is a continuation-in-part of U.S. application Ser. No. 10/794,387 filed Mar. 5, 2004 and this application is a continuation-in-part of U.S. application Ser. No. 10/872,139 filed Jun. 18, 2004.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] The invention relates in general to papermaking, and in particular relates to the manufacture of paper suitable for use as ticket stock used for making redemption tickets of the type commonly dispensed from automated machines in game arcades and the like.
[0003] Game arcades often have electronic games that dispense redemption tickets as a reward for having played the game well. Depending on the game score achieved by the player, the game machine dispenses a different number of tickets. The tickets typically can be redeemed for prizes such as toys, stuffed animals, candy, and the like.
[0004] The game machines generally employ an automated ticket dispenser that dispenses a number of tickets based on the game score. The tickets are supplied in the form of a roll of interconnected tickets separated from one another by perforations. The tickets usually have a printed bar code on one side and may have other indicia and/or graphics on the opposite side. The automated ticket dispenser includes an optical sensor that detects the bar code or other printed marking on each ticket, and in that manner the dispenser is able to count how many tickets are dispensed. Arcades sometimes also include ticket counting machines that operate on a similar principle, such that tickets to be redeemed are fed into the counting machine, which counts the tickets by using an optical sensor.
[0005] For proper functioning of the ticket dispensers and ticket counters, and for good aesthetics of the tickets, it is important that the paper or stock making up the tickets have a high opacity so that printed ink on one side of the tickets does not show through to the other side. At the same time, it is desirable for the tickets to have a soft feel in the hand, to have edges that are not so sharp as to pose a risk of cutting the users' hands, to have relatively high strength so they are not easily torn, and to have a highly smooth surface for good printability. Currently available ticket stocks do not always achieve all of these desirable characteristics.
[0006] The majority of ticket stocks currently being produced are formed on multiply paper machines, and have a thickness or caliper of about 9.5 to 13 points (i.e., 0.0095 to 0.013 inch). Some ticket stock is also produced as a coated solid bleached sulfate (SBS) sheet with a caliper as low as 7 points, but the coating is essential for achieving sufficient opacity to enable proper functioning of the automated ticket dispensers. Such coated SBS ticket stock generally does not have a desirable soft feel in the hand.
[0007] Ticket stock of lower caliper is desirable for improving the ticket yield per unit weight of the papermaking furnish, and for increasing the number of tickets per roll of a given diameter. However, reducing the caliper generally has an adverse impact on some of the other desirable characteristics. For instance, a thinner paper, all other things being equal, has a reduced opacity, a reduced stiffness, and a reduced strength. There is also a certain caliper threshold below which the tickets do not have a good “feel” in the hand, as being too flimsy or insubstantial. It is generally thought that the practical lower limit is about 6.5 to 7 points, as tickets below this caliper level generally feel flimsy and are not favored by consumers.
[0008] Additionally, although some ticket stocks are colored, there is a sizeable market for white ticket stock. Such white ticket stock must have a high brightness.
[0009] Accordingly, it would be desirable to provide a white ticket stock of relatively low caliper, such as about 7 to 9 points, more preferably about 7 points, having a high opacity, a soft feel, and a highly smooth surface for good printability.
BRIEF SUMMARY OF THE INVENTION
[0010] Tickets are widely used for prize redemption in family entertainment centers, arcades, location-based entertainment centers, amusement parks, and similar establishments. Tickets may also be used to conduct drawings, raffles and give-a-ways.
[0011] Organizers of events and companies that dispense tickets typically order tickets by the tens of thousands, and often by the truckload. Beyond the expense of purchasing the actual ticket, ticket-purchasing organizations may expect to pay shipping and storage fees.
[0012] The present invention relates to one or more of the following features, elements or combinations thereof. A ticket is illustratively formed from a sheet or strip of a substrate. The substrate is illustratively reply card stock paper. The substrate may have a caliper characteristic in the range of 5 and 11 points. The opacity of the substrate may be below 98%. The substrate may be manufactured and formed into rolls of tickets, or may be manufactured and formed into decks of tickets. Alternatively, the substrate may be manufactured and formed into sheets of tickets or individual tickets. A roll of 2000 tickets may have a diameter of less than 6.5 inches. The roll of 2000 tickets may have a weight of less than one pound. The rolls may be packaged in a container that has smaller dimensions than the previously-known shipping container. A container holding four rolls across may have a smaller side dimension than 13.5 inches.
[0013] In another embodiment, a ticket is illustratively formed from a sheet or strip of a substrate. The substrate is illustratively high opacity ticket stock. The substrate has a caliper characteristic in the range of 5 to 7.5 points. The opacity of the substrate is above 98%. The substrate may be manufactured and formed into rolls of tickets, or may be manufactured and formed into decks of tickets. Alternatively, the substrate may be manufactured and formed into sheets of tickets or individual tickets. A roll of 2000 tickets may have a diameter of less than 6.5 inches. The roll of 2000 tickets may have a weight of less than one pound. The rolls may be packaged in a container that has smaller dimensions than the previously-known shipping container. A container holding four rolls in a two-by-two fashion may have a smaller side dimension than 13.5 inches.
[0014] The invention addresses the above needs and achieves other advantages, by providing a ticket stock and manufacturing process wherein a pulp is formulated from a blend of recycled furnishes, with added starch for enhancing sheet stiffness and reducing linting and dusting on cut edges of the stock, and with added clay or other opacifier for enhancing opacity of the stock. A preferred pulp comprises a blend of recycled solid bleached sulfate plate stock, recycled coated soft white, and recycled ground wood furnish such as newsprint or the like. In one embodiment, the blend comprises about 25-50 wt. % recycled solid bleached sulfate plate stock, about 25-50 wt. % recycled coated soft white, and about 15-25 wt. % recycled ground wood furnish. Starch can be added in the amount of about 25 to 35 pounds per ton of the finished stock. Clay can comprise about 80 to 120 pounds per ton of the finished stock.
[0015] The ticket stock preferably has a caliper of about 7 to 9 points, more preferably about 7 points. The formulation of the pulp leads to an opacity (measured according to the TAPPI 519 method) of at least about 98 percent. The ticket stock has a Parker Smoothness not substantially exceeding about 8 microns, more preferably not substantially exceeding about 6 microns, and still more preferably not substantially exceeding about 5 microns.
[0016] A process for making a ticket stock in accordance with the invention entails formulating a pulp from a mixture of recycled furnishes as noted above, and adding starch and clay or other opacifier to the pulp. The recycled furnishes are repulped with minimal mechanical refining or fiber shortening. The pulp is then processed at elevated temperature to hydrate and soften the fibers; this can be accomplished, for example, in a unit that injects steam into the pulp while the pulp is at a high consistency. In the case where the recycled furnish includes some printed furnish, this treatment is also effective to break up ink and other contaminants into very fine particles.
[0017] Next, the pulp is fed at a suitable consistency level to a former, which forms a wet web. The former can comprise any of various formers known in the art, including single-ply and multi-ply formers. In one embodiment, a fourdrinier former is employed to form a single-ply web.
[0018] The wet web is then dewatered and pressed in a press section. The press section can comprise various types and numbers of presses. In one embodiment, the press section comprises two sequentially arranged presses such as roll presses equipped with dewatering fabrics. The web is then advanced through a drying section. The drying section can be of various configurations. In one embodiment of the invention, the drying section comprises a series of heated drying cylinders that the web is brought into contact with in turn. The web can be urged into firm contact with the cylinders by fabrics.
[0019] After drying, the web is fed through a soft nip calendar. The calendaring of the web imparts a smooth surface to the web for good printability and enhances the soft feel of the web.
[0020] Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0021] Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
[0022] FIG. 1 is a schematic depiction of a papermaking machine and process in accordance with one embodiment of the invention;
[0023] FIG. 2 is a schematic illustration of one cylinder group of the drying section in accordance with one embodiment of the invention; and
[0024] FIG. 3 shows a roll of redemption tickets formed of a stock in accordance with an embodiment of the invention.
[0025] FIG. 4 shows a perspective view of a prior art roll of tickets and the smaller, new roll of tickets made according to the present disclosure;
[0026] FIG. 5 shows a front elevation view of an end of a prior art ticket and an end of a ticket made according to the present disclosure;
[0027] FIG. 6 shows a perspective view of a portion of a double roll;
[0028] FIG. 7 shows a perspective view of a deck of folded tickets;
[0029] FIG. 8 shows a top view of a container packed with the prior art rolls of tickets;
[0030] FIG. 9 is a top view similar to that of FIG. 5 , showing a container packed with rolls of tickets made according to the disclosure; and
[0031] FIG. 10 is a top view of the space formed between four rolls, showing the space saved when the rolls are made according to the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0032] The present inventions now will be described more fully hereinafter with reference to the accompanying drawings, in which some but not all embodiments of the invention are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
[0033] With reference to FIG. 1 , an apparatus and process for making a paper suitable for use as a ticket stock is illustrated. The process begins by placing a mixture of furnishes into a pulper, or repulper, 10 along with a quantity of water and agitating the mixture to break the furnishes down into a pulp. The mixture of furnishes comprises a blend of recycled furnishes. A preferred mixture comprises a blend of recycled solid bleached sulfate plate stock, recycled coated soft white, and recycled ground wood furnish such as newsprint or the like. In one embodiment, the blend comprises about 25-50 wt. % recycled solid bleached sulfate (SBS) plate stock, about 25-50 wt. % recycled coated soft white, and about 15-25 wt. % recycled ground wood furnish. A particularly advantageous blend comprises about 30 wt. % SBS plate stock, about 50 wt. % coated soft white, and about 20 wt % newsprint. The furnishes advantageously are blank or unprinted, but alternatively one or more can be printed. The pulper 10 preferably repulps the furnishes without any substantial degree of mechanical refining or fiber shortening. In this regard, the pulper preferably comprises a large open metal vessel with a high shear agitator in the bottom. A slurry of pulp at a consistency of 4%-6% solids is formed by feeding dry paper bales along with process white water into the pulper and agitating until the slurry can be extracted through a perforated plate and pumped to a receiving chest for further processing.
[0034] After the furnishes are pulped in the pulper 10 , the resulting pulp is cleaned using suitable cleaning equipment 12 to remove certain undesirable contaminants such as plastic, metal, glass, wood splinters, and dirt. The cleaning equipment comprises liquid cyclone cleaners which continuously remove particles of high specific gravity and contaminant materials such as sand, glass, paper clips, and staples, and also includes barrier screens which are designed to continuously remove oversized particles from the pulp stream prior to refining and formation.
[0035] The pulp is then fed into a disperser 14 that injects steam into the pulp while the pulp is at a high consistency (e.g., approximately 12%-20%). The disperser is a horizontally oriented, pressurized cylindrical vessel with a screw type feeder designed to keep slurry moving continuously through the vessel. The injected steam softens and hydrates the fibers of the pulp. Additionally, if any of the furnish used is printed, the steam injection breaks the inks down into very small particles which remain in the finished product but can barely be seen with the naked eye. Pigment in the form of high-brightness clay can be added later in the process to offset the loss of brightness caused by the presence of ink.
[0036] The pulp is fed from the disperser into a machine chest 16 where additional water is added to the pulp to reduce the consistency to a level suitable for paper forming. Additionally, one or more additives can be added to the pulp at this stage. For example, advantageously an amount of clay, liquid opacifier, or other opacifying agent can be added to the machine chest 16 for enhancing the opacity of the finished paper. In one embodiment, clay is added in an amount of about 80 to 120 pounds per ton of the finished paper stock.
[0037] Next, a process of fiber refining 18 can be performed using suitable equipment such as fractionating units or the like, to achieve a pulp having fiber lengths in a desired range. Such fractionating units and processes are known in the art and hence need not be described in detail herein. Advantageously, the pulp after the refining step 18 has developed sufficient bonding sites on the fiber cell walls for strength development with minimum fiber length reduction. Following the refining step, a size agent such as starch can be added to the pulp as shown. Starch can be added in the amount of about 25 to 35 pounds per ton of the finished stock.
[0038] The pulp advantageously is then subjected to a thin stock cleaning process 20 . This process consists of pumping dilute slurry (<1% solids) through a bank of multiple high velocity centrifugal cleaners to remove a large percentage of remaining fine particle contaminant materials (approx. 70%-90% removal rate).
[0039] The pulp is then fed into a headbox 22 of a fourdrinier former 24 . The headbox injects a stream of pulp onto a traveling wire 26 of the former. Dewatering elements 28 beneath the wire drain some of the water from the web formed on the wire. Advantageously, a Dandy roll 30 (i.e., essentially a roll with a wire screen wrapped about it) contacts the upper surface of the formed web to assist in web formation.
[0040] The web formed in the fourdrinier former 24 is advanced to a press section 32 for further dewatering. The press section can comprise various types and numbers of press devices, including roll presses, extended-nip or shoe presses, or the like. In the illustrated embodiment, the press section comprises a first roll press 34 and a second roll press 36 . Each of the roll presses includes a pair of dewatering fabrics (not shown) between which the wet web is sandwiched. The fabrics with the web therebetween are passed through the nip between the two rolls of the press. The pressure exerted on the fabrics and web causes water to be transferred from the web into the fabrics, as known in the art. The linear nip load exerted on the fabrics and web is generally higher in the second press 36 than in the first press 34 . For example, the nip load in the first press advantageously can be about 400 lb/linear inch (PLI) while the load in the second press can be about 1400 PLI.
[0041] The web can be treated by a steam box 38 prior to the press section 32 in order to heat the wet sheet and improve pressing and drying efficiency.
[0042] After pressing, the web is fed through a dryer section 40 for thermally drying the web to a desired low moisture content. The dryer section is made up of a first group of heated drying cylinders 42 and a second group of heated drying cylinders 44 . Each group of cylinders includes a pair of fabrics for urging the web against the cylinders. FIG. 2 shows the first group of cylinders 42 in greater detail. The cylinders are arranged so that the web W passes in serpentine fashion about each cylinder in turn, whereby one side of the web contacts the first cylinder, the other side of the web contacts the next cylinder, and this alternate cycle repeats for the next two cylinders, etc. A first fabric 46 is arranged to pass around a first set of the cylinders 42 . Guide rolls 48 guide the first fabric 46 from one cylinder to the next and allow the fabric to wrap about a substantial proportion of the circumference of each cylinder. The web W is arranged so that it is between the first fabric 46 and each cylinder 42 . A second fabric 50 is arranged to pass around a second set of the cylinders 42 , and guide rolls 52 guide the second fabric from one cylinder to the next and allow the fabric to wrap about a substantial proportion of the cylinder circumferences.
[0043] The second group of drying cylinders 44 likewise has a pair of fabrics that operate in the way described above.
[0044] With reference again to FIG. 1 , after the web exits the drying section 40 , it can optionally be coated on one or both sides in a coating applicator 54 . The applied coating(s) can then be dried in a dryer 56 . Advantageously, however, a ticket stock in accordance with preferred embodiments of the invention does not have any coating.
[0045] Next, the web is passed through a calender 58 . The calender advantageously comprises a soft nip calender wherein one of the calender rolls has a surface that is deformable so that the nip formed between the deformable roll and the opposing roll is somewhat elongated rather than being a single tangent point between two rigid rolls. The calender is preferably heated. A suitable calendering temperature is between about 400.degree. F. and about 500.degree. F. Calendering of the web in the soft nip calender imparts a smooth surface to the web for good printability, and enhances the soft feel of the web.
[0046] Finally, the finished web is wound into a roll in a reel-up 60. The roll of finished stock typically is shipped to a converter where it is converted into redemption tickets or other products. In the case of redemption tickets, the stock is unwound from the roll, slit, perforated, printed, and wound into individual rolls of redemption tickets such as the roll 70 shown in FIG. 3 .
[0047] The stock in accordance with preferred embodiments of the invention is manufactured to have a caliper of about 7 to 9 points, more preferably about 7 points. The formulation of the pulp leads to an opacity (measured according to the TAPPI 519 method) of at least about 98 percent for the finished stock, more preferably at least about 99 percent. The stock preferably has a Parker Smoothness, on at least one of its surfaces, not substantially exceeding about 8 microns, more preferably not substantially exceeding about 6 microns, and still more preferably not substantially exceeding about 5 microns.
[0048] As an example of a stock made in accordance with one embodiment of the invention, a white ticket stock was manufactured from 30 wt. % SBS plate stock, 50 wt % coated soft white, and 20 wt. % blank newsprint. Clay was added to the pulp in the amount of about 100 pounds per ton of the finished stock. Starch was added in the amount of about 28 to 31 pounds per ton of finished stock. The stock was manufactured using the above-described process, without the optional coating. Five rolls of the stock were prepared, and three samples from each roll were tested for various properties. The average of all samples was computed for each measured property. The average properties are listed below:
[0049] Caliper: 6.84 points
[0050] Basis Weight: 32.65 lbs/1000 ft.sup.2
[0051] Density: 4.78 lbs/point (per 1000 ft.sup.2)
[0052] Tensile Modulus (MD): 47 lbs.
[0053] Water Drop (TAPPI RC-70): 103 secs. (back), 85 secs. (top)
[0054] Taber Stiffness: 18.9 g-cm (MD), 10.2 g-cm (CD)
[0055] Parker Smoothness: 5.97.mu. (top), 4.29.mu. (back)
[0056] Minolta Color (avg. of top and back): 84.72 (L), 1.77 (A), 2.51 (B)
[0057] Opacity (TAPPI 519): 99.61%
[0058] The finished stock was clean and bright, with little or no specs or particles that could pick off the surface when printed. The stock had a matte finish and a generally soft feel in the hand. Slit edges were clean and substantially free of linting or dusting.
[0059] A ticket 100 , as can be seen in FIG. 4 , may be illustratively used for admission to or for point of purchase applications at any of the following: social events, festivals, carnivals, amusement places, parking lots, academic functions, religious functions, and athletic events, among others. Such a ticket 100 may be available in a wide variety of sizes, shapes, and colors, and may or may not have markings relating to the event. Ticket 100 may be punched, perforated, numbered, or die cut. Ticket 100 can be specifically designed for hand issue, machine issue, mechanical collection, collection and accounting by weight, and/or collection and accounting by audit.
[0060] The illustrative tickets 100 may be provided on a roll 120 of 2000 continuous tickets, commonly called “roll tickets” in the industry, as can be seen in FIG. 4 . In such an embodiment, tickets 100 are configured to be unrolled from the roll 120 and separated along perforations 280 in increments desired by the dispensing party. Alternatively, tickets 100 may be formed in groups of two or more, and can be dispensed two or more at a time from a “double roll” 140 , as can be seen in FIG. 6 . A double roll comprises 2000 sets of two tickets, and can be used, for example, in a raffle or lottery scenario. However, it should be understood that other configurations and embodiments are within the scope of the disclosure, and multiple tickets may be rolled adjacent each other. Furthermore, any number of tickets may be provided on a roll, and the tickets could alternatively be grouped in strips or sheets, or may be presented individually or in any other manner known in the industry.
[0061] The common ticket 200 , which has been known in the art for years, uses a substrate of “common ticket stock” paper having a caliper characteristic of approximately 9.5. Typically, the common ticket stock is comprised of ticket bristol paper, and has an illustrative thickness B, as can be seen in FIG. 5 . In contrast, ticket 100 is illustratively printed on a stock of paper that is considered “return postcard” or “reply card” stock paper. Such reply card stock having the same length and width dimensions may have a thickness A (as can be seen in FIG. 5 ). The caliper range may be between 5 and 11 points. The illustrative reply card stock has a caliper of 7. Common ticket stock is comprised of ticket bristol paper, and has an illustrative thickness B, as can be seen in FIG. 5 . In contrast, ticket 100 is illustratively printed on a stock of paper that is considered high opacity ticket stock paper. Such high opacity ticket stock having the same length and width dimensions may have a thickness A (as can be seen in FIG. 5 ). The caliper range may be between 5 and 7.5 points. The illustrative high opacity ticket stock has a caliper of 7. Tickets are illustratively formed to have a width of one inch and a length of two inches, although other dimensions are within the scope of the disclosure.
[0062] Additionally, the opacity of a paper may be considered. Common ticket stock typically has an opacity of 99% or greater. The illustrative reply card stock has an opacity of less than 98%. Such reply card stock having a caliper between 5 and 11 points and/or having an opacity below 98% can be ordered from paper supply companies such as International Paper, headquartered in Stamford, Conn., and Boise Cascade headquartered in Boise, Id. The common ticket stock is much thicker and heavier than the high opacity ticket stock presently disclosed. The illustrative high opacity ticket stock has an opacity of greater than 98%, while having a caliper range of between 5 and 7.5 points. Such high opacity ticket stock can be specially ordered from paper supply companies using the characteristics discussed herein.
[0063] It should be understood that while the illustrative substrates are reply card stock paper and high capacity ticket stock paper, other substrates providing the opacity and caliper characteristics suggested are within the scope of the disclosure. For example, the substrate may be a polymer-based material.
[0064] Use of the reply card stock and high capacity ticket stock described provides a ticket 100 having a substantially smaller thickness A than the thickness B of common ticket 200 constructed of common ticket stock, as demonstrated in FIG. 5 . The smaller thickness also provides a ticket roll 120 of 2000 tickets that has a substantially smaller diameter than the common ticket roll 220 of 2000 tickets, as can be seen in FIG. 4 . Illustratively, a common ticket roll 220 has a diameter of approximately seven (7) inches, and the ticket roll 120 according to specification has a diameter of approximately six (6) inches. The smaller diameter of ticket roll 120 compared to ticket roll 220 allows a box or container 160 of ticket rolls 120 to be shipped and stored in a smaller container 160 than a box or container 240 of ticket rolls 22 , as can be seen by comparing the dimensions of containers 160 and 240 , shown in FIGS. 8 and 9 . The smaller dimension of container 160 allows more containers 160 to be shipped in a given amount of space, i.e. a truckload, and allows more ticket rolls 120 to be stored in a given amount of storage space. Illustratively, container 16 has side dimensions of less than 13.5 inches.
[0065] The high opacity of greater than 98% prevents bleeding or burn-through of ticket dispensing sensors. Such sensors are typically optical sensors and misreadings can occur when lower opacity stock paper is used. A typical optical sensor is used for ticket-counting purposes by utilizing the combination of a light beam and sensor positioned on opposite sides of the strip of tickets being dispensed, the light sensor “reading” when the light shines through an aperture or notch 38 formed in the strip of tickets 10 . In lower opacity and/or caliper characteristics, such ticket-counting by light sensors may be impaired.
[0066] A container 160 shipping ticket rolls 120 made according to the present disclosure is also a more efficient means of shipping ticket rolls because the space 320 between rolls 120 is of smaller dimension than the space 340 between rolls 220 . By shipping less air and the same number of tickets, the shipping is more efficient. FIG. 10 illustrates the space saved by using rolls 120 of the present disclosure. The cross-hatched area 360 of FIG. 10 illustrates the shipping space saved when utilizing the presently disclosed rolls 120 .
[0067] Use of reply card stock or high capacity ticket stock can also provide a ticket 100 having less weight. A common single-ticket roll 220 of 2000 tickets, as shown in FIG. 4 , weighs approximately 1.10 pound. A ticket roll 120 of 2000 tickets according to the specification weighs approximately 0.65 pound. Because shipping costs are commonly calculated at least partially based on the weight of the shipment, the lighter weight of the ticket rolls 120 permits a savings on shipping costs to a consumer. Single-ticket rolls 220 , such as those shown in FIG. 4 , are illustratively shipped in containers 240 having 40 ticket rolls 220 . When such single-ticket rolls 220 are manufactured from common ticket stock, the approximately weight of container 240 is forty-seven (47) pounds. When single-ticket rolls 120 are manufactured from the illustrative reply card stock, the approximate weight of container 160 is twenty-eight (28) pounds. Common double-ticket rolls of 2000 tickets weigh approximately 2.35 pounds each, and double rolls 140 according to the disclosure weigh approximately 1.35 pound each.
[0068] It is within the scope of the disclosure to provide rolls of any number of tickets. For example, a double roll of 1000 tickets may be provided (not shown). If such a double roll were manufactured from common ticket stock, the diameter would be approximately five (5) inches and the weight would be approximately 1.1 pound. If the double roll were manufactured from the illustrative reply card stock, the diameter would be approximately 4.375 inches and the weight would be approximately 0.65 pound. If the double roll were manufactured from the illustrative high opacity ticket stock, the diameter would be approximately 4.375 inches and the weight would be approximately 0.90 pound.
[0069] The present disclosure is not limited to tickets on rolls, but can also be applied to sheet tickets, folded decks 180 of tickets (as can be seen in FIG. 7 ), and any other type of ticket known in the art. One use of folded decks 180 is that of redemption tickets, wherein the tickets are dispensed from a game of skill or chance for redemption of a prize. When decks 180 of tickets 100 are used in such a format, it may be necessary to reconfigure the ticket-counting device associated with the ticket dispenser. For example, a typical ticket-counting device (not shown) uses the combination of a light beam and sensor positioned on opposite sides of the strip of tickets being dispensed, the light sensor “reading” when the light shines through an aperture or notch 380 formed in the strip of tickets 100 . In some opacity and caliper characteristics disclosed herein, such ticket-counting by light sensors may be impaired. In the alternative, the light sensor may be configured to read a “dark” spot on the ticket 100 , rather than a light shining through a notch 380 . In such an embodiment, a dark line may be printed across a ticket where the ticket passes under the ticket-counting device, and the notch 380 may be omitted from the ticket 100 . However, it should be understood that the described embodiment is merely one example of how a ticket-counting device may be configured, and other examples are within the scope of the disclosure.
[0070] It is within the scope of the disclosure to provide a ticket with a light-sensor-triggering marking imprinted thereon. Such a light sensor could be used as a ticket counter.
[0071] A method of manufacturing tickets is also disclosed. The method includes the steps of unwinding a portion of a roll of reply card stock paper, feeding the unrolled portion through a printer, cutting the paper to form strips of paper, and perforating the strips of paper to form separable tickets therebetween. The method may include rolling tickets 100 on a tube 260 (visible in FIGS. 4 and 9 ) in a roll 120 of 2000 tickets 100 . Alternatively, the method may include forming decks 180 of tickets, typically accordion-folded with five tickets 10 disposed between each fold line 30 , as can be seen in FIG. 7 . Decks 180 are illustratively packaged in sets of 3000 tickets, although it is within the scope of the disclosure to combine any number of tickets to form a deck.
[0072] A method of shipping tickets is also provided by the disclosure. The method includes the steps of providing rolls of 2000 in a container measuring less than 14 inches on each side.
|
A ticket stock and manufacturing process wherein a pulp is formulated from a blend of recycled furnishes, with added starch for enhancing sheet stiffness and reducing linting and dusting on cut edges of the stock, and clay or other opacifier for enhancing opacity of the stock. A preferred pulp comprises a blend of recycled solid bleached sulfate plate stock, recycled coated soft white, and recycled ground wood furnish such as newsprint or the like. In one embodiment, the blend comprises about 25-50 wt. % recycled solid bleached sulfate plate stock, about 25-50 wt. % recycled coated soft white, and about 15-25 wt. % recycled ground wood furnish. The furnish blend is repulped with minimal mechanical refining, is treated with steam injection for hydrating and softening the fibers, and is formed into a web that is pressed, dried, and soft calendered. The caliper of the resulting stock is about 7 to 9 points and provides a ticket for use in prize redemption in family entertainment centers, arcades, location-based entertainment centers, amusement parks, and similar establishments. The ticket may also be used to conduct drawings, raffles and give-a-ways. The ticket may be formed from a sheet of reply card stock paper having a caliper characteristic in the range of 5 and 11 points.
| 3
|
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/169,014 filed on Dec. 3, 1999.
FIELD OF THE INVENTION
The present invention relates to spindle bearing assemblies, and more particularly to those including a plurality of raceways containing rolling members compressed with a controlled preload force.
BACKGROUND OF THE INVENTION
Although the use of such bearings is common in devices incorporating small electric motors, such as disc drives, preload force variations in such bearings are difficult to control in practice. Variations that reduce the preload force can cause play between the rotating and stationary members and/or undesired oscillations. Variations that increase the preload force can cause other problems, such as excessive or uneven wear in the bearings and/or balls.
Although some control mechanisms exist within the systems that apply the preload force, the need for spindle bearings having an internal control mechanism remains to be satisfied.
SUMMARY OF THE INVENTION
Spindle bearings are assembled with at least one annular gimbal to compensate for undesired components of bearing compression force. Spindle bearings are provided with a pair of coaxial raceways that are separated so that a first assembly can rotate with respect to a second. Balls rollingly engage the inner and outer races to maintain the races in coaxial alignment, typically with an offset preload so that the balls are kept in compression.
A preferred gimbal of the present invention has a somewhat oblong cross section along a radial half-plane and is formed integral to the assembly by cutting at least one groove about a rigid portion to make a deformable layer about 0.5 millimeters thick. Alternatively, the gimbals may be pre-formed and affixed to a rigid member to form the assembly.
Type I embodiments of the present invention compensate for operational force variations such as those caused by temperature variation. Type I devices include gimbals on one or both assemblies, compensating for variations in these forces that might otherwise become excessive. Some Type I devices are disc drives using stainless steel spindle bearings with balls made of ceramic. Ceramic balls typically have a thermal coefficient of expansion less than a fourth that of steel, often resulting in unacceptably large force variations in response to thermal variations less than 40 degrees Centigrade. Ceramic balls are much harder than stainless steel, however, resulting in favorable durability characteristics for applications such as disc drives.
A “rigid” element as used herein is a continuous mass of hard material (such as steel) of which no portion will be displaced from the rest by more than a few nanometers by ball bearing preloads less than 6 pounds. An “annular gimbal” as used herein is an annular mass of resilient material(s) such as steel arranged about an axis of symmetry. Gimbals of the present invention typically have a thickness Less than the diameter of the balls. Preferred disc drives of the present invention feature at least one spindle bearing gimbal with a spring constant 1 to 4 times larger (stiffer) than the balls in the spindle bearing assembly, under nominal normal operating conditions.
Type II embodiments of the present invention compensate for force variations that can occur during assembly, such as those caused by misalignment during the application of a preload. Gimbals of the present invention, when partially compressed or stretched, exert a restoring force that tends to equalize the preload force about the bearings. Virtually all conventional preload application mechanisms have enough give that this restorative force provides a helpful repositioning mechanism.
Additional features and benefits will become apparent to those skilled in the art upon reviewing the following figures and the accompanying detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art disc drive comprising a disc stack mounted onto the hub of a spindle bearing assembly.
FIG. 2 shows a method of the present invention for making an improved spindle motor.
FIG. 3 shows a disc drive having a spindle bearing exemplifying the present invention with an X-type preload.
FIG. 4 shows another preferred method of the present invention.
DETAILED DESCRIPTION
Numerous aspects of disc drive or spindle bearing technology that are not a part of the present invention (or are well known in the art) are omitted for brevity. These include (1) detailed design or assembly of motor components; (2) the operation of recording discs, disc clamping mechanisms, or other technologies specific to disc drives; and (3) specific structures of basic bearing assemblies or preload application mechanisms. Although the examples below show more than enough detail to allow those skilled in the art to practice the present invention, subject matter regarded as the invention is broader than any single example below. The scope of the present invention is distinctly defined, however, in the claims at the end of this document.
FIG. 1 shows a prior art disc drive 200 comprising discs 105 mounted onto a hub 114 of a spindle bearing assembly 100 . Two coaxial ball bearing raceways are defined by outer bearing races 111 mounted to a rigid cylindrical support 112 and inner bearing races 113 mounted to a rigid shaft 115 . An armature core 116 is mounted on the outer peripheral surface of the support 112 . A drive magnet 117 is affixed onto the inner surface of the hub 114 . Armature core 116 and the drive magnet 117 and other parts make up a motor, which rotates the drive magnet 117 so as to rotate the hub 114 together with the drive magnet 117 .
FIG. 2 shows a method of the present invention for making an improved spindle motor, including steps 210 through 230 . Two raceways are constructed 212 , each comprising first and second race members. Suitable races are readily available for use in constructing race members of the present invention. A “race member” as used herein is an annular race or a rigid or gimbaled assembly that includes at least one annular race. As will become clearer from a review of FIG. 4, step 212 of constructing is preferably accomplished by gluing, welding, shrink-fitting, or integrally forming extensions onto at least one of the ordinary races.
Next, the second members of each raceway are affixed together into a common assembly having at least one gimbal between the second members 218 . The rolling members are then preloaded 222 so that the gimbal(s) are partially deformed as the first members are affixed into a common assembly 225 . Note that at steps 222 and 225 , gimbals are partially deformed so that they tend to compensate for any non-uniformity in the axial preloading force.
FIG. 3 shows a disc drive 400 having a spindle bearing assembly 300 of the present invention. Discs 390 are mounted in alternation with disc spacers 392 to form a disc stack having an axis of rotation 305 . A first set of balls 310 is positioned for movement along a first circle 312 , which is defined by the rotation of radius 317 about axis 305 . Upper races 313 , 314 compress the balls 310 along one of the axes of compression 315 as they roll. Each of the axes of compression 315 forms an acute angle 306 with axis 305 that is preferably less than about 80 degrees. The angle 306 may be inward as shown for an “X-type” preload, or may be outward for a “diamond-type” preload. It will be seen that the angle 306 and the preload magnitude each interact with the axial gimbal-deflecting force of the present invention.
A second set of balls 320 is positioned for movement along a second circle 322 defined by the rotation of radius 327 about axis 305 . Upper outer race 314 , backiron 330 , magnet 332 , hub 334 , and an outer vertical portion 351 of grooved member 350 are coupled together in a first rigid assembly that is configured for rolling engagement with the first set of balls 310 . Lower outer race 324 is coupled with an inner vertical portion 353 of grooved member 350 in a second rigid assembly that is configured for rolling engagement with the second set of balls 320 .
In addition to the vertical portions 351 , 353 , grooved member 350 includes an annular gimbal 352 . Gimbal 352 is operatively coupled between the first and second rigid assemblies, able to bend so that an axial force of less than 6 npounds between the rigid assemblies can produce an appreciable gimbal deformation. As gimbal deformation will be “appreciable,” for clarity as used herein, if it effects a ball bearing preload reduction of at least 0.1% as compared with the force that would exist in the absence of deformation. Gimbal deformation(s) allow the first rigid assembly to move axially with respect to the second rigid assembly, even after the inner races 313 , 323 are coupled together to form a complete rigid assembly.
Extending “substantially along” major surface 358 (e.g. best fit by least squares method) is a reference line 318 that passes through the axis of rotation 305 and forms a hinge angle 308 therebetween which will shift as gimbal 352 deforms. Annular gimbal 352 has a thickness 355 (measured perpendicular to the reference line 318 ) that is desirably about about 0.2 to 0.8 millimeters, and a width 356 (along reference line 318 ) that is desirably about 2 to 10 times larger. The axes of compression 315 and the reference line 318 desirably form a compression transfer angle 305 (in each plane passing through axis of rotation 305 ). A preferred gimbal 352 of the present invention has a compression transfer angel 305 in the range of about 10 to 25 degrees.
Alternatively, the reference line 318 of a given half-plane may be defined to maximize the ratio of the gimbal width 356 to the average gimbal thickness 355 perpendicular to that width 356 . This definition is also exemplified by FIG. 3 .
To increase the gimbal's deflection, gimbal 352 has a major surface 358 that is substantially perpendicular (i.e. within a few degrees) to the axis of rotation 305 . Note that gimbal 352 need not be a uniform layer but may take other shapes that will allow a deflection having an appreciable axial deflection such as a section of a bowl, cone shape, or toroid. In some cases, gimbal thickness will vary greatly. In the general case, a reference line is desirably constructed which is parallel to a line “substantially along” a surface midway between opposite major surface, of the gimbal. Reference line 318 meets this definition. Whatever variation in materials and geometry is used in the practice of the present invention, it is recommended that each gimbal generally have a minimum thickness that is less than the diameter of the rolling elements.
In a preferred embodiment, the balls 310 , 320 and the rigid assemblies essentially comprise a common alloy such as a steel, so that they expand fairly uniformly with temperature. Suitable steel balls 310 , 320 (e.g. SAE 52100) and rigid components optionally have a Rockwell Hardness (HRC) of about 56 to 59. In a most preferred embodiment, the balls 310 , 320 are instead made of a ceramic. Suitable ceramics, are readily commercially available that are significantly harder and more durable than steel. Unfortunately, ceramics generally have smaller coefficients of thermal expansion than hard alloys suitable for the rigid assemblies of a disc drive spindle bearing assembly. So that temperature variation will not cause large preload force variation, structures of this embodiment use a gimbal designed for preload force compensation.
FIG. 4 shows another preferred method of the present invention, comprising steps 410 through 475 . At least one annular groove is machined into a bearing housing to provide a predetermined gimbal thickness 415 . For a single-layer stainless steel gimbal such as that of FIG. 3 for use in a typical disc drive, the gimbal is desirably about 0.6 millimeters thick (with a tolerance of about 0.02 to 0.10 mm) over at least half of the gimbal's width. A nominal gimbal thickness greater than about 0.2 to 0.3 millimeters is preferred, because lesser gimbal thicknesses will require tolerances smaller than about 0.02 to 0.05 mm for a satisfactory degree of predictability in the gimbal's restorative force (i.e. modulus of elasticity). Such precise tolerances can increase manufacturing costs significantly.
Other materials may readily be substituted for part or all of the gimbal structure, so long as their dimensions are selected for similar resilience (i.e., within a few orders of magnitude). Lesser thicknesses may increase manufacturing costs because of the necessity of restrictive machining tolerances. Greater thicknesses, however, may reduce the axial range of gimbal deflection excessively.
Before or after machining the gimbal 415 , the bearing housing is glued onto the first raceway's outer member 420 . A large inner race element is constructed by gluing the shaft onto the first raceway's inner race 425 and onto the stator 430 .
After wiring the stator 435 , a large outer race element is constructed by affixing the backiron to the magnet 440 , to the hub 445 , and to the second raceway's outer member 450 . Next, glue is applied to the bearing housing/backiron joint 455 and to the shaft/second inner race member element 460 . Construction of the spindle bearing is completed by applying an axial preload while allowing the glue to cure 470 . The spindle bearing can then be assembled into a disc drive, and the disc(s) can be mounted onto the hub 470 .
In FIG. 3, the gimbal's movement is substantially axial (i.e. within about 1 degree of the axis of rotation) within its range. The angle between the axes of ball compression and of gimbal compression is desirably at least 5-15 degrees over the gimbal's range of motion, so that the gimbal can deflect significantly in response to ball bearing compression values less than 5 pounds.
Note that the structure of FIG. 3 can be obtained by methods other than those of FIG. 2 or 4 , such as by fully deflecting the gimbal before completing the assembly. Conversely, the distinct methods of FIGS. 2 & 4 can each be used to make structures unlike that of FIG. 3, such as those having a gimbal on each of the two assemblies configured for relative rotation.
Referring again to the example of FIG. 3, Type I embodiments are presented above with a spindle bearing 300 part of which is configured for rotation about an axis 305 . A first set of balls 310 is positioned for movement along a first circle 312 within a raceway about the axis 305 . A second set of balls 320 is positioned for movement along a second circle 322 about the axis 305 . A first member (which includes outer race 314 ) is configured for rolling engagement with the first set of balls 310 , and a second member (which includes outer race 324 ) is configured for rolling engagement with the second set of balls 320 . This structure is improved by the inclusion of at least one annular gimbal 352 operatively coupled between the first and second members and able to bend so that the first member (including race 314 ) moves axially with respect to the second member (including race 324 ). After placing the gimbal(s), methods of the present invention include a step 225 , 465 of completing one or both assemblies for relative rotation.
FIG. 3 also exemplifies preferred Type I embodiments in which each ball of at least one set 320 has an axis of compression 315 forming an angle 306 with the axis of rotation 305 that is less than about 80 degrees. FIG. 3 defines a radial half plane extending to the right of axis 305 , which typifies radial half planes of the disc drive 400 . A reference line 318 is shown that intersects the axis of rotation 305 at an acute angle 308 greater than 45 degrees. Each ball of at least one set 320 also has an axis of compression 315 that intersects its respective reference line 318 to form a compression transfer angle 308 that is desirably less than about 25 degrees.
Referring again to the examples of FIGS. 2 & 4, Type II embodiments are presented above as methods of assembling a spindle bearing from components including first and second bearing assemblies each comprising a set of balls in raceways. An annular gimbal on the first raceway's second member is constructed 415 , to which the other raceway's “second member” is affixed 218 , 455 , 465 . While urging the second members away from one another so as to deform the gimbal partially 222 , the “first members” are then assembled into a common fixed or gimbaled assembly 226 , 465 . This preload configuration will result in an X-type preload. Alternatively, step 465 can be performed with second members being urged toward one another so that a diamond-type preload will result.
All of the structures described above will be understood to one of ordinary skill in the art, and would enable the practice of the present invention without undue experimentation. It is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and function of various embodiments of the invention, this disclosure is illustrative only. Changes may be made in the details, especially in matters of structure and arrangement of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. For example, steps of the above methods can be reordered while maintaining substantially the same functionality, without departing from the scope and spirit of the present invention. In addition, although the preferred embodiments described herein are largely directed to spindle bearing configurations especially suitable in magnetic disc drives, it will be appreciated by those skilled in the art that many teachings of the present invention can be applied to other systems without departing from the scope and spirit of the present invention.
|
According to the present invention spindle bearings are assembled with at least one annular gimbal to compensate for undesired components of bearing compression force. Specific devices and methods are directed to compensating for either (a) operational force variations such as those caused by temperature variation or (b) assembly-related force variations such as those caused by misalignment.
| 5
|
CONTRACTUAL ORIGIN OF THE INVENTION
The United States Government has rights in this invention pursuant to Contract No. DE-AC02-76CH03073 between the U. S. Department of Energy and Princeton University.
BACKGROUND OF THE INVENTION
This invention is directed to the diagnosis and detection of gross or macroinstabilities in a magnetically-confined fusion plasma device. Detection is performed in real time, and is prompt such that correction of the instability can be initiated in a timely fashion.
A plasma in a magnetic field has a tendency to be unstable; as a result, it can break up and escape from confinement by the field. Plasma instabilities are due basically to the presence of electrically charged particles; the electric and magnetic fields produced by their motions cause the particles to act in a collective, or cooperative manner. An example of such collective action is the drift of a plasma in a non-uniform magnetic field. Similar collective effects give rise to plasma instabilities. These instabilities fall into two broad categories, called "gross hydromagnetic instabilities" and "more localized microinstabilities". Suppose, for example, a small displacement of a plasma occurs in a magnetic field; if the system reacts in such a way as to restore the original condition, then it is stable. In the case of a hydromagnetic (or gross) instability, however, the plasma does not recover, but the displacement increases rapidly in magnitude. The whole plasma may then break up and escape even from a strong magnetic field.
Microinstabilities, as the name implies, are on a small scale compared with the dimensions of the plasma. As a rule, these instabilities do not lead to complete loss of confinement, but rather to an increase in the rate at which the plasma diffuses out of the magnetic field. This invention is directed to the former type of instabilities, the gross or macroinstabilities.
The term "plasma instability" refers to any cooperative plasma motion that can regenerate itself, starting from normal levels of random flunctuations or of plasma irregularities, in a time short compared to collision processes in the plasma. Thus, plasma instability can connote motions that range all the way from a gross motion of the plasma as a whole across a confining field, to high frequency, short-wavelength isolations of the plasma accompanied by intense flunctuating electric fields, but perhaps by little transport.
By their nature, gross instabilities are slow growing, that is their growth rate is much less than the ion cyclotron frequency, and involve wave lengths that are generally large compared to particle orbit diameters. They owe their origin to a simple circumstance: if a magnetically confined plasma can convert some of its internal kinetic energy to a directed motion by distorting or moving in some direction across the confining field, this process will occur. Though they are slow growing, compared to fine-scale instabilities, the effects of gross instabilities on confinement are the most catastrophic of all. Their growth time scale is of the order of the transit time of an ion through the confinement chamber--i.e., of the order of microseconds in fusion plasmas situations.
This invention is directed to disruptive instabilities which are characterized by a sudden, large disturbance that develops very rapidly (typically tens to hundreds of microseconds in ohmically heated plasmas), and is accompanied by hard x-ray bursts, flattening of a current profile with expulsion of poloidal flux and prominent negative voltage spikes, loss of energy, and shift of the plasma column to smaller major radius. Small disruptions may repeat several times; large ones may terminate the discharge.
Major plasma disruptions present a formidable design problem because of the rapid release of both thermal and magnetic energy. In general, disruptions are expected to occur at the limits of operation in current and/or density, but the mapping of an essentially disruption-free operating machine has been an empirical exercise for each device.
The design impact of a sudden loss of confinement is severe. Indeed, for all large tokamaks, major disruptions play an important role in first wall design. References which describe the engineering overdesign required by the occurrence of plasma current disruptions in Tokamaks are: "Mechanical Engineering Aspects of TFTR, J. C. Citrolo, Princeton Plasma Physics Laboratory Report No. PPPL-1988 [983], and Engineering Asppects of Disruption Current Decay", J. G. Murray, ORNL/FEDC-83/S(1983). Major disruptions also play a significant role in determining the requirements for vessel clean-out, plasma control, vertical field coil placement, and they even impact toroidal field coil design (when superconducting coils are employed). For example, a major disruption on a typical long pulse, d-t burning tokamak will cause the deposition of 100 to 200 MJ of plasma energy onto the surface of the first wall on a time scale short compared to the thermal diffusion time, so as to cause rapid heating and subsequent vaporization of substantial quantities (of the order of kilograms) of wall material.
It is obviously beneficial to provide a mechanism for control of major disruptions. In addition to the engineering advantages associated with the reduced thermal loading to the first wall and to the limiter, a reduction of severe JxB forces on coils, the prevention of the major disruption also allows lower q operation, which, if β p is limited by balooning, implies a higher beta operation. While some success has been achieved in disruption control, the techniques employed also present major design problems when examined in a reactor context.
It is therefore an object of the present invention to predict the occurrence of a major plasma disruption in real time, with enough advance lead time to allow corrective plasma control actions to be taken.
It is another object of the present invention to provide a plasma diagnostic technique which reveals plasma instability precursors, is easy to operate, and which can be implemented with a minimum-size system comprised of standard laboratory devices.
SUMMARY OF THE INVENTION
These and another objects of the present invention are provided for a magnetic plasma confinement device having an inner wall of a plasma containment vessel. An inner toroidal limiter is located on the inner wall of the vacuum vessel, and contact with the confined plasma is made during times of plasma disruptions. According to the invention, a time scan of a vertical temperature profile along the inner toroidal limiter is performed at brief intervals, using a time-scanning infrared camera or photodetector array. The time scans are continuously observed for the appearance of a peak temperature excursion. According to the present invention, the peaked temperature excursion is a precursor of a subsequent major plasma disruption. Having detected the peak temperature excursion, corrective action can be taken to lessen the deleterious effects of such disruption.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, wherein like elements are referenced alike:
FIG. 1 is a partial schematic plan view of a magnetic plasma confinement device having an inner toroidal limiter arrangement;
FIG. 2 is a schematic elevational view of the device of FIG. 1;
FIG. 3 is a partial schematic plan view showing a diagnostic arrangement employed in the present invention;
FIG. 4 shows a typical temperature profile following a neutral beam heated discharge in the arrangement of FIGS. 1-3;
FIG. 5 shows a decay rate of temperature profiles following the neutral beam heated discharge of FIG. 4;
FIG. 6 shows a temperature profile sequence preceding and succeeding a disruption in an ohmic heated discharge;
FIG. 7 shows a temperature profile following a disruption of an ohmic heated discharge; and
FIG. 8 shows a theoretical plot of peak separation versus scrape-off length for the toroidal limiter of FIGS. 1-3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be described with reference to a particular magnetic confinement plasma device, the Poloidal Diverter experiment (PDX), located at Princeton University, Plasma Physics Laboratory. As will be appreciated by those skilled in the art, the present invention can be readily adapted to other applications.
The Poloidal Diverter experiment is being used to study impurity control and another significant processes in high-temperature neutral beam heated plasmas. With reference to the schematic plan view of FIG. 1, the PDX machine 10, a tokamak, has a toroidal vacuum vessel 12 for containing a magnetically-confined plasma. The plasma is heated by four neutral beam injectors, 21-24, as explained in the following references: W. L. Gartner et al, "Proceeding of the 8th Symposium on Engineering Problems of Fusion Research", San Francisco, Calif. 1979, (IEEE, N.Y, N.Y.) p. 972; M. M. Menon et al., also appearing in the "Proceeding of the 8th Symposium on Engineering Problems of Fusion Research", p. 656; and H. W. Kugel and M. Ulrickson "The Design of the PDX Tokamak Wall Armor and Inner Limiter System", American Nuclear Society, Nuclear Technology/Fusion, Vol. 2, October, 1982, pp. 712-722. The four beam lines inject a total heating power of 6 MW H 0 or 8 MW D 0 . The injection is at a nearly perpendicular injection angle (9°). The measured neutral beam power density profile in the focal plane is almost axially symmetric and approximately Gaussian from the maximum power point to about 10% of maximum with a characteristic half-angle-at-1/e of 1.1° to 1.8°. The expected maximum power density on beam axis at the inner wall of the torus for a 300 millisecond injection is 3.2 kW/cm 2 . Eventual 500 millisecond injection pulse lengths are anticipated. Incident power densities of this magnitude, for pulse durations up to 500 milliseconds, require the protection of the 0.95 cm thick 304 stainless steel inner wall of PDX. The adopted armor plate consists of arrays 30 of water cooled, titanium carbide coated graphite tiles 32, supported on inner wall 34 of the torus, opposite each beam port. Channels 36 formed in tiles 32 provide paths for coolant flow. Titanium plates 38 shield the gaps between the graphite units.
The PDX wall armor is designed to function as an inner wall thermal armor, a neutral beam power diagnostic, and a large area inner plasma limiter. The maximum PDX neutral beam power densities are capable of melting the surface of the 0.95 cm thick stainless steel-304 inner wall in about 250 milliseconds if injection occurs in the absence of a plasma, i.e., during conditions allowing essentially 100% power transmission to the inner wall. During normal operation with typical PDX plasma densities, beam transmission is approximately 10-30%, thus proportionally reducing the power density through the inner wall. However, if a disruption in the plasma current occurs during neutral beam injection, the transmitted power could increase to its maximum value. In principle, beam injection is terminated by a sense circuit approximately 10 milliseconds after the disappearance of the plasma current. However, the PDX armor is designed to accommodate this range of conditions and increase the margin of safety while adequately shielding the inner wall of the torus from full power for 0.5 seconds in the absence of the plasma.
Several systems are provided to study neutral beam heating in PDX, including the direct measurement of injected power or power density for a variety of beam and plasma conditions. These systems generally comprise an array of 64 thermocouples installed in the graphite tiles, and calibrated calorimeters installed in the water cooling lines 36 which cool the graphite tiles. Window ports on the outer wall 40 of the torus permit the use of IR cameras to monitor the front face temperature of the armor at regions of maximum power deposition. Such measurements provide a safety diagnostic for monitoring the integrity of the armor and also yield useful information on armor front face temperature profiles and effective heat transfer coefficients.
The PDX inner wall armor (i.e. array 30) is designed to also function as a plasma limiter. It has been estimated that a conventional poloidal rail inner limiter has a peak plasma thermal load of the order of 2 kW/cm 2 at mid-plane, whereas in an axisymmetric toroidal limiter, the peak plasma thermal load at mid-plane would be about 200 W/cm 2 (J. A. Schmidt, "Comments on Plasma Physics and Controlled Fusion" Vol. 5 (1980) p. 225. This substantially lower thermal load for a toroidal limiter is expected to provide a reduction in impurity emissions, and thermal fatigue. The PDX toroidal limiter configuration will contribute useful information concerning plasma and disruption thermal loads for a nearly axisymmetric limiter, impurity emissions, surface damage, mechanical stability, and overall reliability.
Access to the PDX vessel is obtained via 31 cm by 34 cm ports. This places a maximum size constraint on all armor components and installation procedures. The PDX plasma has a minor diverted radius of 47 cm and a major diverted radius of 145 cm. Undiverted dimensions are 57 cm and 145 cm, respectively. The toroidal radius of curvature of the PDX inner wall is 71.4 cm. This relatively small radius of curvature requires armor segments of a comparable curvature or, equivalently, many narrow flat plates. However, practical constraints required the selection of a flat plane geometry of 9.93 cm front face width for the PDX armor design as a compromise between maximizing flat plate width in order to reduce the required total number of plates, and minimizing the amount of plate-edge exposure and protrusion beyond the mean armor radius as the plate width is increased. An armor length of 61 cm (or 30.5 cm above and below the mid-plane), was chosen to prevent protrusion beyond the shielding provided by the upper and lower inner limiters. The design tile length produced an approximately square tile shape, with an odd number of tiles per backing plate. An approximately square shape achieves a more symmetric thermal expansion, while an odd number of tiles was chosen to eliminate any gap at the mid plane where the neutral beam power is greatest. Each of the four armor units consists of three subunits containing either two or three backing plates, which provide mounting to inner wall 34. The graphite armor units cover approximately 70% of the circumference of the inner wall, and each graphite armor unit is positioned to intercept injected neutral beams. The 30% of the inner wall circumference that does not receive direct neutral beam power is armored with titanium plate which acts as an inner wall plasma calorimeter for measuring thermal loading during normal operations and disruptions in the plasma current. The armor is grounded to the PDX vessel which is electrically isolated during plasma shots.
The following is a description of vertical temperature toroidal limiter, during both ohmic and neutral beam heated discharges. With reference to FIG. 3, the vertical temperature profiles along the graphite tile array 30 were taken with a scanning infrared camera 50 which views array 30 through a conventional high transmission Zinc Selenide infrared window 52 formed in outer wall 40 of device 10. Camera 50 is an Inframetrics Model 210 scanning infrared camera, which was positioned to view the limiter of array 30 from a distance of about 2 meters. The camera operates in two wavelengths ranges: 3 to 5 micrometers, and 8 to 12 micrometers. The camera was used in a line scan mode where temperatures along a single line are recorded. Since the camera used is designed for horizontal scanning operation only, a conventional 90° image rotator 54 (such as Inframetrics Model No. AC048) was employed upstream of the camera to facilitate vertical scanning of array 30. It will become immediately apparent to those skilled in the art, that an array of infrared photodiodes can be substituted for the infrared camera, if less stringent spatial resolution requirements are acceptable.
The time response of the system was about 125 microseconds, and a scan was taken every three milliseconds. The scans were archived using a computer data acquisition system. The camera and signal processing electronics were calibrated using standard black body sources. The emissivity of the limiter surface was detemined by uniformly heating the limiter by circulating warm water (approximately 50° C.) through the limiter cooling lines, and comparing the infrared signal to the limiter thermocouples. It was found that the emissivity was different for the two wavelength bands. The emissivity for the 3 to 5 micrometer band was 0.95 to 0.98 across the face of the limiter, while emissivity in the 8 to 12 micrometer band varied between 0.4 and 0.7. In view of the greater signal-to-background ratio obtained with the 3 to 5 micrometer band, and the relatively constant emissivity at these wavelengths, the results presented here were obtained using the 3 to 5 micrometer band. After the correction for emissivity, the temperatures determined from the two wavelength bands agreed to within plus or minus 10° C.
The measurements were performed during a period of extensive high beta plasma studies as described in "High-Beta Experiments with Neutral Beam Injection on PDX", D. Johnson et al, "Plasma Physics and Controlled Nuclear Fusion Research 1982" (Proceedings of the 9th International Conference, Baltimore, 1982) IAEA, Vienna, Vol. 1, No. 9 (1982). The temperature profiles measured on the inner toroidal limiter were obtained using both co-and-counter injection geometry. The discharges were typically initiated at the major radius and then brought into contact with the inner limiter. The inner toroidal limited plasmas had a major radius of 125 cm and a minor radius of 40 cm.
FIG. 4 shows a typical vertical temperature profile following a beam heated discharge. A shift of the thermal pattern below the mid plane (see d=0 in FIG. 4, and line 60 in FIG. 2) is unexplained at this time. The asymmetry of the two peaks 62, 64 is tentatively presumed to be due to the directed momentum of the fast beam particles. The asymmetry is seen most strongly following neutral beam, as opposed to ohmic heating shots. The ratio of the thermal load in the two peaks is about 0.3. The temperatures are consistent with about 40% of the input power during the beam pulse going to the limiter.
The decay rate for the temperature profiles following beam heated discharges is shown in FIG. 5. The dotted line is the result of a theoretical calculation of the limiter front face temperature using temperature dependent material parameters and a peak thermal load of 0.25 kW/cm 2 for 200 milliseconds. The thermal load was reduced from the temperature rise during the beam portion of the discharge. The time dependence of the power load during the beam could not be determined because of noise problems caused by the beam. The noise was due to electrical pickup and possibly beam heating of small bits of dust on the limiter surface resulting in small hot spots. It was observed that the predominant thermal load occurs during the beam portion of the discharge. This is consistent with the very small temperature rises observed during non-disruptive portions of ohmic heated discharges.
An array of 64 thermocouples mounted in the graphite tiles 32 was used to monitor the toroidal asymmetry of the thermal depositions. Data taken from the array show that the power deposition was toroidally symmetric except in those areas where there were inner wall diagnostic apertures. In these locations, power is deposited on the edge of the aperture and/or behind the limiter, resulting in slightly higher power deposition.
Measurements of ohmic heated discharges followed the beam-heated discharges described above. Typical plasma parameters include: toroidal magnetic field of approximately 12 kilogauss, I p between the 220 and 270 kilo-amperes, line average electron density 2.5 10 -13 cm -3 , and a magnetic safety factor (q) of 3.5.
FIG. 6 shows a typical temperature profile sequence preceding and following a major disruption 70 of an ohmic heated discharge. It was observed that a single heat precursor profile 72 appeared about 50 milliseconds prior to a major disruption 70, within an initial rate of rise of 2.4° C. per millisecond. The temperature of profile prior to the disruption could not be determined because the heat flux from the ohmically heated discharge was too small to cause measurable temperature differences across the graphite limiter. A series of inner wall temperature profile measurements were made over several hours of operation using sensitive thermocouples mounted on a titanium plate on the north-side of the limiter wall. Examination of these measurements revealed a double peak that occurred during normal ohmic heated discharges [a phenomenon reported by R. J. Fonck, et al, "Impurity Levels and Power Loading in the PDX Tokamak with High Power Neutral Beam Injection", "Plasma Surface Interactions in Controlled Fusion Devices, 1982", (Proceedings of the 5th International Conference, Gatlinburg, Tenn., June 1982), J. Nucl. Mater., 111 & 112, 343 (1982)]. Note also that the sequence of temperature profiles 74 following the disruption are double peaked and initially symmetrical.
FIG. 7 shows a typical temperature profile following a disruption in an ohmically heated discharge. The deposition is still shifted down by about the same amount as was found for the neutral beam heated discharges (see FIG. 4). Theoretical calculations of front-face tile temperature using temperature dependent material parameters and a thermal load of 5-10 kW/cm 2 for the 3-6 millisecond duration are consistent with observed temperatures. This load time is consistent with the measured plasma current decay rate of approximately 42 kiloamperes per millisecond. The temperature histories prior to the disruption indicate a thermal load of less than 20 W/cm 2 .
The Schmidt model for scrape-off of a toroidal limiter [J. A. Schmidt, "Tokamak Impurity-Control Techniques", "Comments on Plasma Physics and Controlled Fusion", Vol. 5, 225 (1980)] predicts a double peaked temperature profile. Using this model, the scrape-off length (λ) was derived as a function of the separation of the temperature peaks for the case of a flat, vertical, inner toroidal limiter. The results are shown in FIG. 8, a plot of one-half theoretical peak separation versus λ. The inferred scrape-off lengths are=1.0 cm for the neutral beam discharges and λ=0.5 cm for the postdisruption ohmic heated discharges. These values are consistent with other measurements made on PDX, as reported in "Interactions in Controlled Fusion Devices 1982" (Proc. 5th Intl. Conf. Gatlinburg, Tenn., June, 1982), J. Nucl. Mater., 111 & 112, 130 (1982). The observed symmetry in the toroidal direction is predicted by the model. A peak power load of 250 w/cm 2 , deduced from the temperature profile, agrees with the peak power predicted by the model for 40% of the input power going to the limiter. The filling in of the valley between the peaks indicates the presence of a radial transport which is not included in the model in an explicit manner. While radial transport is implicitly included in the scrape-off thickness in the model, the power is assumed to flow only along field lines. This results in the power flux being predicted to be zero at the limiter plasma tangency point (midplane in the PDX case). The same radial transport which results in the scrape-off length will carry power to the tangency point, [according to S. A. Cohen, R. Budny, G. M. McCracken, M. Ulrickson, "Mechanisms Responsible for Topographical Changes in PLT Stainless-Steel and Graphite Limiters," J. Nucl. Fus. 21, 233 (1981)] and fill in the profile, as was observed. The lack of a double peak before disruption implies that the radial transport is greatly enhanced just prior to disruption. While it is true that enhanced radial transport will result in longer scrape-off lengths giving a wider peak separation, it will also result in more filling in of the space beween the peaks. Also, the longer scrape-off lengths result in lower peak power densities. Under such conditions, the radial transport to the tangency point can dominate the power flow. This could be particularly true if field lines are becoming stochastic prior to a disruption.
Those skilled in the art could implement various methods for automatically detecting the precursor peaks. For example, a simple method involves focusing several individual infrared photodiode detectors to view points on the surface of the inner limiter laying along a vertical line. A rapid increase in the signal strength from detectors viewing the midplane of the limiter relative to the signal strength of detectors viewing the outer edge of the limiter would indicate the presence of the disruption precursor. Either the relative rates of change in the respective signal strengths, the relative absolute differences in signal strength, or ratios of the signal strength between the respective detectors could be monitored for the disruption precursors. Indicators such as these could be introduced into a control feedback loop or used to trigger an electronic threshold to cause corrective control action to be taken. A more elaborate method, for example, involves using fast automatic data processing equipment to analyze the temperature profile detected with an array of individual detectors or a scanning camera system. The fast automatic data processing system could be programmed to recognize the characteristic disruption precursor pattern and adjust the tokamak operating parameters in a suitable manner to avoid the disruption or to reduce its severity.
Thus it can be seen that in those major plasma disruptions characterized by a temperature profile precursor, a fast infrared camera arranged according to the present invention can detect the precursor in time to provide a realtime interval before disruption, which allows ameliorating, or even fully corrective action to be taken. In the above example, the time interval prior to disruption was 50 msec. An example of corrective action that can be taken within this time is cited in "The Effect of Current Profile Evolution on Plasma-Limiter Interaction and the Energy Confinement Time", R. J. Hawryluk, et al., Nucl. Fusion Vol. 19 (1979) p. 1307, which describes an automatic control of operating parameters so as to optimize reactor performance and avoid the aforementioned deleterious effects of a plasma disruption. It is anticipated that other, more fully corrective measures, will be devised so as to sustain continuous operation despite potential plasma disruptions. The arrangement of the present invention can be employed to initiate such corrective action.
Another use of this invention is to detect the presence of so-called stationary mode plasma instabilities, i.e. plasma instabilities characterized by non-fluctuating, non-rotating, stationary magnetic structures in the plasma which are undetectable using the conventional magnetic sensing coils used to detect rapid fluctuations in magnetic structure.
|
In a magnetic plasma confinment device having an inner toroidal limiter mounted on an inner wall of a plasma containment vessel, an arrangement is provided for monitoring vertical temperature profiles of the limiter. The temperature profiles are taken at brief time intervals, in a time scan fashion. The time scans of the vertical temperature profile are continuously monitored to detect the presence of a peaked temperature excursion, which, according to the present invention, is a precursor of a subsequent major plasma disruption. A fast scan of the temperature profile is made so as to provide a time interval in real time prior to the major plasma disruption, such that corrective action can be taken to reduce the harmful effects of the plasma disruption.
| 6
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present general inventive concept relates to a sewing assembly and method for a sewing machine, and in particular, to a sewing assembly and method that enables the sewing machine to utilize a thread supply on a bobbin while permitting automatic reloading of the bobbin during use thereof.
[0003] 2. Description of the Related Art
[0004] The textile industry, which includes sewing, quilting, and embroidery, manufactures yarn, thread, and the like (hereinafter “thread”) by winding finished thread onto a carrier or “bobbin” for storage until use of the thread. Bobbins are typically elongated, cylindrical barrels that are attachable to a sewing machine, as illustrated in FIG. 1 , to be unwound by the sewing machine so that the sewing machine may produce a desired stitch pattern.
[0005] A popular stitch pattern is “lockstitch,” which is performed by most household sewing machines and industrial single-needle sewing machines using two threads, an upper thread passed through a needle and a lower thread coming from the bobbin. Each thread stays on the same side of the material being sewn, interlacing with the other thread at each needle hole. Industrial lockstitch machines with two needles, each forming an independent lockstitch with their own bobbin, are also common.
[0006] The textile industry has long struggled with inefficiencies due to the necessity of winding, rewinding and/or replacing the bobbin and thread. Over the years, there have been a number of attempts to address these inefficiencies by attempting to improve the functionality of bobbins used with sewing machines.
[0007] For instance, U.S. Pat. No. 2,262,665 discloses a bobbin having an annular groove with circumferentially spaced portions to prevent thread slipping relative to the bobbin spindle during winding of the thread on the bobbin.
[0008] Similarly, the bobbin disclosed in U.S. Pat. No. 3,284,023 includes a V-shaped notch or groove and a protuberance formed in its exterior surface to form a yarn trap also to prevent thread slipping relative to the bobbin spindle during winding of the thread on the bobbin.
[0009] More recently, a textile core including a V-shaped start-up groove with a roughened sidewall surface formed therein was disclosed in U.S. Pat. No. 5,211,354.
[0010] Contributing to the aforementioned inefficiencies is the problem that the bobbin with lower thread will often become depleted of thread before the upper thread, which may go unnoticed by an operator. Moreover, both the upper thread and the lower thread are subject to breaking, which can be caused by the thread and also go unnoticed by the operator. Any sewing operation performed without both the upper and lower threads will require repeating of the sewing operation.
[0011] Several methods to facilitate monitoring of the condition of the upper thread have been disclosed, for instance, in U.S. Pat. No. 3,843,883. However, monitoring the condition of the lower thread on the bobbin is relatively difficult for at least the reason that the lower thread and the bobbin are typically concealed from the operator's view. Thus, the condition of the lower thread is typically not noticeable or detectible until an object being sewed by the sewing machine begins to unravel, which alerts the operator to the missing bobbin thread.
[0012] On multi-head sewing and embroidery machines, this is especially problematic because once the bobbin runs out on one head, the entire machine must be stopped to feed the missing bobbin thread.
[0013] Some conventional machines, such as that disclosed by U.S. Pat. No. 5,143,004 to Mardix, disclose a sensor and complex arrangement of parts that are supposed to sense when thread is not being fed to a sewing needle by a bobbin and to automatically change the bobbin. These machines, however, are prone to malfunction, which causes bobbins to be replaced before they are depleted thereby wasting thread. Additionally, the machines are expensive to manufacture, difficult to maintain, and do not remedy the problem of a bobbin running out of thread or otherwise decrease the frequency of required bobbin changes. Each bobbin change is labor consuming and time consuming, which substantially reduces productivity of the sewing machine.
[0014] Other conventional machines are disclosed by U.S. Pat. No. 3,405,379 to Wilson, U.S. Pat. No. 4,049,215 to Husges, U.S. Pat. No. 4,681,050 to Kosmas, and U.S. Pat. No. 5,143,004 to Mardix.
[0015] Despite these advances in the art, however, a need remains for a long-lasting and inexpensive bobbin that reduces the number of times a bobbin must be changed thereby decreasing the likelihood that a sewing operation must be repeated due to a depleted bobbin, enables an operator to easily observe whether a bobbin thread is depleted or broken, is economical to manufacture, use, and maintain, and prevents waste of thread.
[0016] Therefore, it is desirable to provide a new and unique bobbin assembly and method that satisfies these needs.
SUMMARY OF THE INVENTION
[0017] The present invention satisfies these needs and achieves the additional advantages detailed below.
[0018] The present general inventive concept provides a sewing bobbin apparatus and method that monitors for a bobbin that is at and/or nearing depletion of its thread, and automatically refills its thread via a spool of bobbin thread that is much larger than those of conventional machines and oriented to permit observation of the spool during use thereof by an operator. Instead of less than 100 yards of thread on a bobbin, as is the approximate capacity of conventional machines, the present inventive concept allows the utilization of spools with 1000s of yards, thus reducing the number of times the spool must be inspected and/or changed, and thereby decreasing the likelihood that a sewing operation must be repeated due to a depleted bobbin.
[0019] This present general inventive concept allows for the use of large spools of bobbin thread. Instead replacing the bobbin, the bobbin is actually rewound in place. This present general inventive concept allows the utilization of spools with thousands of yards of thread, thus minimizing downtime requiring during bobbin replacement of conventional machines.
[0020] The foregoing and/or other aspects and utilities of the present general inventive concept may be achieved by providing a tube that is operable to feed the bobbin thread via blowing air through the tube, so that the thread is delivered directly into the bobbin case where it is attached to the spinning bobbin through the use of grippers.
[0021] A bobbin winder/rewinding motor with rollers contacts the bobbin and spins the spool, rewinding the bobbin. The bobbin is then released from spinning and the thread is cut and the sewing process continues. The tube containing the bobbin thread rests outside of the bobbin case waiting for a signal from a sensor. The spinning bobbin is driven by a contact roller mechanism entering the side of the bobbin case. As previously stated, the bobbin can be rotated for winding by a direct drive mechanism. The bobbin rewinding mechanism may have rollers that can make contact with the bobbin. An opening in the bobbin case allows the roller or rollers attached to the motor to make contact with the bobbin. Access space accommodates the tube housing the bobbin thread. The motor spins the bobbin independent of the shuttle drive mechanism, allowing for the thread to become attached to the bobbin core through the use of grippers, and the bobbin will be wound full of thread. This same assembly can be used on either a straight shaft machine or an angled drive machine. The bobbin rewinding motor assembly must be able to move in and out, making contact with the bobbin for only the amount of time necessary for rewinding/filling.
[0022] This present general inventive concept improves the sewing machine efficiency by allowing the use of very large spools of thread that rewind the bobbin in place in the machine, minimizing operator attention and improving efficiency. It is also configurable to any type of bobbin shaft/gear configuration. The Bobbin Feed Tube may bring the bobbin thread to the bobbin winding assembly. This can be performed via air blowing the thread or manually fed through the tube. The bobbin winder motor assembly may shift into position to rewind the bobbin and the thread being blown into the spinning bobbin. After the bobbin full of thread, the bobbin winder motor assembly may move back to the start position and the needle with the upper thread moving into the sewing position. The shuttle hook may grab the upper thread and pull it around the bobbin. The shuttle hook with the upper thread may contact the bobbin thread coming from the feeding tube. The upper thread may pull the bobbin thread into the tensioner and past the sensor, and then cut the bobbin thread at the feed tube. In this manner, the present inventive concept provides for continued sewing until the bobbin sensor detects no bobbin thread at which point the aforementioned process is repeated.
[0023] The foregoing and/or other aspects and utilities of the present general inventive concept may further be achieved by providing a bobbin assembly including a bobbin, a thread support element for supporting a spool and thread, and an elongated tube for receiving the thread from the spool and routing the thread through a sewing machine and to the bobbin. An air transmission tube operable to deliver a supply of air may also be provided wherein the tube is at least partially aligned with the air transmission tube so that the tube is operable to receive air transmitted from the air transmission tube. An elongated shaft in communication with and operable to rotate the bobbin may also be provided. A bobbin winder operable to selectively rotate the bobbin may also be provided. The bobbin winder may be selectively movable to and from a use configuration and a non-use configuration. The use configuration may be the bobbin winder abutted against the bobbin and the non-use configuration may be the bobbin winder spaced from the bobbin. The tube may be selectively movable to and from a use configuration and a non-use configuration. The use configuration may be the tube adjacent to the bobbin and the non-use configuration may be the tube spaced away from and not adjacent to the bobbin. A plurality of grippers may be provided to project from the bobbin, the plurality of grippers operable to snag the thread from the spool.
[0024] The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing a method of sewing using a bobbin assembly, the method including installing a spool having a thread on a thread support element, and feeding the thread from the spool into an elongated tube. The method may further include the step of blowing the thread through the tube via air transmitted from an air transmission tube. The method may further include the step of blowing the thread through the tube and to a bobbin. The method may further include the step of rotating the bobbin to accumulate a supply of the thread on the bobbin. The method may further include the steps of catching an upper thread via a bobbin element, adding tension to the thread via the upper thread, and cutting the thread via a cutting element.
[0025] The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing a non-transitory computer readable medium containing computer instructions stored therein for causing a computer processor to perform the steps of monitoring a condition of a bobbin, and executing a refilling process when the condition indicates that the bobbin is at least partially depleted of a thread, wherein the refilling process includes feeding the thread from a thread supply into an elongated tube. The non-transitory computer instructions may further cause a computer processor to further perform the steps of blowing the thread through the tube via air transmitted from an air transmission tube, blowing the thread through the tube and to a bobbin, rotating the bobbin to accumulate a supply of the thread on the bobbin, catching an upper thread via a bobbin element, adding tension to the thread via the upper thread, and/or cutting the thread via a cutting element.
[0026] Additional aspects and utilities of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept.
[0027] The foregoing and other objects are intended to be illustrative of the present general inventive concept and are not meant in a limiting sense. Many possible embodiments of the present general inventive concept may be made and will be readily evident upon a study of the following specification and accompanying drawings comprising a part thereof. Various features and subcombinations of present general inventive concept may be employed without reference to other features and subcombinations. Other objects and advantages of this present general inventive concept will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, an embodiment of this present general inventive concept.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] These and/or other aspects and utilities of the present general inventive concept will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
[0029] FIG. 1 is a left side elevation view of a conventional sewing machine having a bobbin;
[0030] FIG. 2 is a left side elevation view of the present general inventive concept illustrating a bobbin assembly in use with a sewing machine;
[0031] FIG. 3 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0032] FIG. 4 is a magnified front elevation view of the bobbin of the present general inventive concept illustrated FIG. 2 with related components;
[0033] FIG. 5A is a front elevation view of a wire tensioner of the present general inventive concept illustrated FIG. 2 with related components;
[0034] FIG. 5B is a magnified front elevation view of the wire tensioner of the present general inventive concept illustrated FIG. 5A with related components;
[0035] FIG. 5C is a top plan view of the wire tensioner of the present general inventive concept illustrated FIG. 5A with related components;
[0036] FIG. 6 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0037] FIG. 7 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0038] FIG. 8 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0039] FIG. 9 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0040] FIG. 10 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0041] FIG. 11 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0042] FIG. 12 is a magnified side elevation view of the bobbin of the present general inventive concept illustrated in FIG. 2 with related components;
[0043] FIG. 13 is a left side elevation view of another embodiment of the present general inventive concept illustrating a straight-shaft bobbin assembly and a winder assembly in use with a sewing machine; and
[0044] FIG. 14 is a left side elevation view of another embodiment of the present general inventive concept illustrating a top-loading bobbin assembly and a winder assembly in use with a sewing machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] Reference will now be made in detail to the embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below in order to explain the present general inventive concept by referring to the figures.
[0046] Turning to FIGS. 2-4 , a bobbin assembly 20 includes a sewing machine 22 having a working surface 24 and a bobbin 26 housed beneath the working surface 24 and within the sewing machine 22 . The bobbin 22 is at least partially enclosed by a bobbin cover 28 and/or the shuttle 100 and is controlled by an elongated cylindrical shaft 30 , which engages the shuttle 100 and is operable to selectively rotate the shuttle 100 .
[0047] In communication with the bobbin 22 is a conical spool 32 having a supply of thread 34 thereon. The spool 32 is mounted on a support element 36 located outside of and adjacent to the sewing machine 22 . The supporting element 36 is stationary with an upwardly-projecting element 38 that is insertable into a center of the spool 32 . The supporting element 36 is capable of supporting spools of a variety of sizes such that larger spools, relative to conventional spools (not illustrated), to enable longer spans of use of the present inventive concept without requiring changes of the spool 32 .
[0048] The bobbin 26 is in the form of a cylindrical reel with a circumferential receiving surface 40 on an interior of the bobbin 26 that is operable to receive and support the thread 34 thereon. On either side of the receiving surface 40 are two walls 42 that are operable to contain the thread 34 on the receiving surface 40 . In the exemplary embodiment, the receiving surface 40 has a plurality of thread grippers 44 , e.g., depending fibers or the like, that are each operable to further secure the thread 34 to the receiving surface 40 , e.g., via trapping the thread 34 between the thread grippers 44 to prevent lateral movement of the thread 34 along the receiving surface 40 yet permitting vertical movement of the thread 34 when a force, e.g., a pulling or tugging force, is applied to the thread 34 . It is foreseen, however, that the thread gripper 44 may be omitted without deviating from the scope of the present inventive concept.
[0049] The thread 34 is wound onto the bobbin 26 via securing a portion of the thread 34 to the bobbin 26 and then rotating the bobbin 26 . The bobbin 26 is rotated via a bobbin winder 46 that includes a motor 48 that is operable to rotate a shaft 50 that has a bobbin-engagement portion 52 at an end thereof, as illustrated in FIG. 4 . The motor 48 is powered by an AC/DC power source (not illustrated). The bobbin-engagement portion 52 abuts one or both of the walls 42 of the bobbin 26 , and is made of a resilient material, e.g., rubber or the like, so that the bobbin-engagement portion 52 may be slightly pressed into one or more walls 42 to provide sufficient friction and ensure constant engagement therebetween. Additionally, a hole 54 is provided within the bobbin winder assembly 46 to provide access thereto should such be required during maintenance of the bobbin winder assembly 46 or bobbin 26 .
[0050] The bobbin case 28 is equipped with a bobbin tensioner 56 that is operable to maintain a sufficient degree of tension between the bobbin 26 , the thread 34 , and the spool 32 to prevent any slack in the thread 34 . The bobbin tensioner 56 is a spring or the like that prevents rotation of the bobbin 26 unless a slight amount of force, e.g., a pull force from the thread 34 and/or a rotating force from the bobbin winder assembly 46 , is applied to the bobbin 26 , in which case the bobbin tensioner 56 permits rotation of the bobbin 26 .
[0051] The bobbin case 28 is also equipped with a bobbin sensor 58 that receives the thread 34 therethrough, e.g., between two walls that form a void to receive the thread 34 , and/or is operable to sense whether the thread 34 is no longer within or adjacent to the sensor 58 , which in turn indicates that the thread 34 is or is becoming depleted and replacement is or is about to be required. The bobbin sensor 58 may be, for example, be a circuit that is closed when the thread 34 is not present in the void and that is open when the thread 34 is present within the void. The sensor 58 may be connected to an indicator, e.g., a light (not illustrated), such that when the circuit is open because the thread is not present within the void, the light is off, and when the indicator is closed because the thread is present within the void, the light is on to indicate that the thread 34 is or is becoming depleted and replacement is required or is about to be required.
[0052] The thread 34 is installed onto the bobbin 26 via at least one air supply (not illustrated), e.g., a fan, compressed air, or the like. The air supply is operable to transmit a stream of air from an elongated air-transmitting tube 62 to an elongated air-receiving tube 64 so that when the thread 34 is placed in front of the receiving tube 64 , the thread 34 is blown into and through the receiving tube 64 , through an opening 65 , and to the bobbin 26 . The air supply is preferably manually activated via a switch only during installation of the thread 34 onto the bobbin 26 . It is foreseen, however, that the air supply may be activated automatically and/or maintained in an active state during use of the present inventive concept. Also included is a thread cutter 66 , which is operable to selectively cut the thread 34 between the bobbin 26 and the spool 32 when desired by the user, e.g., after the bobbin 26 has been loaded with the thread 34 .
[0053] Turning to FIGS. 5A-5C , a wire tensioner 70 is provided on a grooved base 72 of the working surface 24 of the sewing machine 22 . The wire tensioner 70 is manufactured from a wire or like material having a degree of resilience. In the exemplary embodiment, the wire tensioner 70 is biased toward the grooved base 72 , so that the thread 34 may be trapped between the wire tensioner 70 and the grooved base 72 so that the user is able to maintain the thread 34 in a desired position on the working surface 24 .
[0054] The sewing machine 22 has a cavity 80 for receiving and supporting the shaft 30 that is operable to rotate the shuttle 100 . The sewing machine 22 receives the shaft 30 into a side thereof. While the shaft 30 is depicted as received parallel to a length of the sewing machine 22 , it is foreseen that the shaft 30 can be received perpendicular to the length of the sewing machine 22 .
[0055] The elongated transmitting tube 64 extends through the sewing machine 22 parallel to the shaft 30 and communicates the thread 34 from an exterior of the machine 22 to an interior of the machine 22 . In this manner, the tube 64 delivers the thread 34 to the bobbin 26 .
[0056] Turning to FIGS. 6-12 , in use, the machine 22 is activated and the bobbin sensor 58 is operable to sense whether the thread 34 is present on the bobbin 26 and available for use. If not, the thread 34 is either manually or automatically fed until the bobbin sensor 58 senses that the thread 34 is present on the bobbin 26 . In other words, the spool 32 is installed onto the support element 36 and the thread 34 is fed into the tube 64 . The air supply is activated to transmit air from the tube 62 , to the tube 64 and the thread 34 is blown through the tube 64 and to the bobbin 26 . The tube 64 is selectively moveable to and from a closer proximity to the bobbin 26 through opening 65 .
[0057] Once the thread 34 is fed through the tube 64 , the thread 34 is continued to be blown until it engages the surface 40 and the grippers 44 , and is then rotatingly wound onto the bobbin 26 by the winder 46 . To perform the winding, the winder 46 is selectively movable through the opening 54 to an abutting relationship with the walls 42 of the bobbin 26 and then activated to rotate the bobbin 26 . At a predetermined point (e.g., after a certain time period passes or a number of complete revolutions of the bobbin 26 , the winder 48 stops and is backed away from the bobbin 26 . When the winder 46 ceases to operate, the air source is deactivated and the tube 64 is also backed away from the bobbin 26 .
[0058] An upper needle 90 and upper thread 92 are then positioned for use with the machine 22 . A shuttle 100 begins rotation a shuttle cock 101 catches the upper thread 92 and positions the upper thread 92 around the bobbin 34 and in relationship to the thread 34 for a sewing operation. The upper thread 92 pulls the thread 34 so that the thread 34 has a tension, which causes the thread 34 to be received into the thread sensor 58 , so that the thread sensor 58 may monitor usage of the thread 34 and alert the user when the thread 34 is depleted or malfunctions (e.g., is no longer capable of being used with the upper thread 92 ). At this point, the thread cutter 66 cuts the thread 34 and the sewing operation may begin.
[0059] It is foreseen that the present inventive concept may be modified without deviating from the scope of the present inventive concept. For instance, bobbin gears may be provided so that the bobbin 26 is oriented horizontally or vertically with respect to the machine 22 , as illustrated in FIGS. 13 and 14 .
[0060] It is also foreseen that various embodiments of the present generally inventive concept can be embodied as computer readable codes (e.g., computer instructions) on a non-transitory computer readable recording medium for causing a computer processor to perform (e.g., functions of the present general inventive concept). The computer readable recording medium may include any data storage device suitable to store data that can be read by a computer system. A non-exhaustive list of possible examples of computer readable recording mediums include read-only memory (ROM), random-access memory (RAM), CD-ROMS, magnetic tapes, floppy disks, optical storage devices, and carrier waves, such as data transmission via the internet. The computer readable recording medium may also be distributed over network-coupled computer systems so that the computer readable code is stored and executed in a distribution fashion. Various embodiments of the present general inventive concept may also be embodied in hardware, software or in a combination of hardware and software. For example, a user interface (not illustrated) may be provided with a controller (not illustrated) to permit a user to operate the present general inventive concept. For instance, when the sensor 58 indicates the bobbin 26 is depleted, the controller may automatically activate the air source (not illustrated) to cause the thread 34 to be routed to the bobbin 26 , which then undergoes the reloading process as previously discussed. In other words, these functions may be embodied in software, in hardware, or in a combination thereof.
[0061] Although a few embodiments of the present general inventive concept have been illustrated and described, it will be appreciated by those skilled in the art that changes may be made in these exemplary embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.
|
A sewing bobbin assembly and method that provides access of a sewing machine, and particularly a bobbin in the sewing machine, to a larger supply of thread with automatic reloading of the bobbin during use thereof.
| 3
|
[0001] This is a Divisional of U.S. application Ser. No. 13/991,231 filed Jun. 3, 2013, which is a National Phase of International Application No. PCT/EP2011/066715 filed Sep. 27, 2011, which claims the benefit of British Application No. 1020401.4 filed Dec. 2, 2010. The disclosures of the prior applications are hereby incorporated by reference herein in their entireties.
FIELD OF THE INVENTION
[0002] The present invention relates to electrical discharge machining (EDM) and more particularly, but not exclusively, to so-called high speed electrical discharge machining (HSEDM) utilised for forming holes in components such as blades for gas turbine engines.
BACKGROUND OF THE INVENTION
[0003] EDM is utilised with regard to processing of workpieces by spark erosion. The workpiece and the electrode (usually made from graphite, copper or brass) are generally presented with a dialectric fluid between them and are connected to a DC power supply (EDM generator) delivering periodic pulses of electric energy, such that sparks erode the workpiece by melting and vaporisation and so create a cavity or hole or otherwise shape a workpiece. In order to provide for spark erosion, the workpiece and the electrode must have no physical contact and a gap is maintained typically through appropriate sensors and servo motor control. Erosion debris must be removed from the erosion site and this usually necessitates a retraction cycle during conventional electrical discharge machining. It is possible to utilise multiple electrodes in a single tool holder to allow several erosion and machining processes to be performed at the same time and normally side by side.
[0004] In HSEDM a high pressure (e.g. 70 to 100 bar) dielectric fluid pump is utilised in order to supply dielectric fluid to the gap between the workpiece and the electrode. As a result of the high pressure presentation of the dielectric fluid, the process is more efficient than conventional EDM, allowing more rapid removal of debris such that erosion rates are far greater. With HSEDM there is no need for retraction cycles between stages of erosion for evacuation of debris, as the high pressure flow of dielectric fluid in the gap between the workpiece and the electrode is more efficient for the removal of debris produced by the erosion process. Thus generally the electrode is simply fed forwards at a speed necessary to achieve the desired rate of material erosion and removal in accordance with the machining process. Continuous operation results in a significantly-faster machining process.
[0005] In the attached drawings, FIG. 1 schematically illustrates a typical HSEDM arrangement for the drilling of holes. The arrangement 1 comprises an electrode holder 2 which presents an elongate electrode 3 to a workpiece 4 . Electrical discharge from the tip of the electrode is provided through a direct current electrical power generator 5 such that a cavity or hole is drilled, formed or machined into the workpiece. Dielectric fluid is supplied at a relatively high pressure (70 to 100 bar) to the cavity or hole defined progressively by a spark gap between the electrode and the workpiece. This high pressure dielectric flow is achieved through a pump 6 which acts on a dielectric fluid supply 7 to force the fluid under pressure as indicated into the gap between the electrode and the workpiece. The high pressure flushes and removes debris caused by the discharge process. A servo motor 8 or other device forces continuous movement of the electrode in the length direction of the electrode, driving the electrode into the workpiece. By monitoring the gap voltage, the servo motor can maintain a gap of constant size. Due to the high pressure dielectric fluid flow, there is rapid removal of debris and therefore generally it is not necessary to have a retraction cycle of the electrode in order to allow flushing as with conventional EDM. Thus, in the normal course of events, the servo motor simply moves the electrode down at the speed necessary to keep up with a desired rate of material removal and/or erosion. The constant motion produced by the servo motor allows for rapid drilling, but if drilling is too rapid there is an increased likelihood of short circuiting. In such circumstances, the servo motor retracts the electrode to allow clearing of the electrical short circuits and debris, and then reintroduces the electrode to reestablish the correct gap size for erosion.
[0006] HSEDM is used for drilling cooling holes and other features in turbine blades for gas turbine engines. Components such as turbine blades have very strict requirements with regard to hole geometry and surface integrity which can be met by HSEDM. However, HSEDM has high production costs and can lead to large variations in typical breakthrough time to form a hole. Also electrode wear necessitating re-working of components can be a problem. For example, it is not uncommon to have relative electrode wear factors which are greater than 100%, i.e. a greater length of electrode can be worn away than the depth of drilled hole. Electrode wear can also lead to tapering of the electrode, as illustrated in FIG. 2A and uneven wear in banks of electrodes, as illustrated in FIG. 2B . Electrodes that become tapered produce tapered holes, with a restriction at an exit end. Uneven electrodes in a multiple electrode tool result in some electrodes not fully penetrating the workpiece to leave blocked holes. Alternatively, if the servo motor needs to feed the electrodes deeper to complete the hole formation, the excess electrode length in some of the electrodes can lead to backwall impingement erosion and so damage other parts of the component. Such backwall impingement erosion is illustrated in FIG. 3 , in which the drilled through-hole 21 in turbine blade 22 continues in the drilling direction 20 into a backwall as unplanned cavity 23 . Thus skilled operation of the HSEDM process can be essential.
[0007] WO 2009/071865 proposes an improved HSDEM process in which ultrasonic cavitation is induced within the pressurised dielectric fluid flow to enhance debris removal and thereby improve continuous machining.
SUMMARY OF THE INVENTION
[0008] However, there is a need for further improvements in electrical discharge machining processes.
[0009] Accordingly, a first aspect of the present invention provides a method for electrical discharge machining a workpiece including the steps of:
presenting an elongate electrode to the workpiece with a spark gap therebetween, flowing a dielectric fluid in the gap, eroding the workpiece by electrical discharge between the tip of the electrode and the workpiece, displacing the electrode in a direction aligned with the long axis of the electrode to maintain the gap as the electrode wears and the workpiece is eroded, and simultaneously with the displacement, producing vibratory movement of the electrode, the vibratory movement being aligned with the long axis of the electrode.
[0015] Advantageously, the vibratory movement of the electrode can induce corresponding vibrations in the dielectric fluid, which cause the fluid to form pulsating jets in the gap. These pulsating jets can help to clear debris from the spark gap, allowing machining to progress at greater speeds. Also, the vibratory movement of the electrode can help to reduce the occurrence of short-circuits between the electrode and the workpiece which can lead to electrode retraction and workpiece damage.
[0016] The method may have any one or, to the extent that they are compatible, any combination of the following optional features.
[0017] Usually, the electrode has an axial bore, i.e. the electrode can be tubular. The dielectric fluid can then be supplied in one direction through the bore and then flow over the outer surface of the electrode. For example, the fluid can exit the bore at an end of the electrode, and then return in the opposite direction over the outer surface of the electrode.
[0018] The electrode can be rotated about its long axis to reduce uneven electrode wear and to improve hole circularity.
[0019] The dielectric fluid may be supplied to the gap at a pressure of from 70 to 100 bar. High fluid pressures help to flush debris from the spark gap.
[0020] The dielectric fluid may be supplied to the gap at an electrical resistivity of from 2 to 17 MΩ.cm. The dielectric fluid can be deionised water.
[0021] The vibratory movement may have a frequency of up to 500 Hz, and preferably of up to 250 or 200 Hz. The vibratory movement may have a frequency of more than 50 Hz, and preferably of more than 80 Hz. The vibratory movement may have a frequency of about 100 Hz.
[0022] Preferably, the vibratory movement is sinusoidal.
[0023] Preferably, the electrode is displaced by a servo system (e.g. based on one or more linear induction motors, or one or more linear actuators such as piezo-electric actuators or pneumatic linear actuators combined with, for example, a lead-screw rotary motor) having a frequency response of at least 1 kHz and more preferably of at least 10, 50 or 100 kHz. Such devices can provide a high vibratory movement frequency. A further advantage of displacing the electrode using such a servo system is that its frequency response can be of a similar order of magnitude to the electrical discharge spark frequency (typically around 1-100 kHz) used in electrical discharge machining. Thus, the machining process can be made more responsive to fast changes in spark gap conditions, leading to a more stable and faster process. In contrast, many conventional electrical discharge machining systems are based on lead-screw servomotors which typically have maximum frequency responses of only about 30 Hz and are thus less capable of maintaining a constant spark gap.
[0024] The vibratory movement may have an amplitude of up to 200 microns, and preferably of up to 75 microns. The vibratory movement may have an amplitude of more than 20 microns. The vibratory movement may have an amplitude of about 50 microns.
[0025] In order that the vibratory movement and fluid jets can clear the debris efficiently from the spark gap, it is typically advantageous to erode the workpiece while maintaining a larger spark gap size than is usual during conventional electrical discharge machining. For example, for a displacement velocity of the electrode of less than 1.5 mm/sec, the spark gap voltage (which is typically used as a measure of the spark gap size) may be greater than 35V.
[0026] The step of flowing the dielectric fluid in the gap can include sending pulsating jets of the fluid to the gap. Such pulsating jets can further improve the rate of debris removal from the spark gap. Conveniently, the pulsating jets can have a pulse frequency which is the same as the frequency of the vibratory movement of the electrode. In the case of an electrode with an axial bore, the pulsating jets can be sent along the bore to the spark gap.
[0027] Any one or more of the rate of electrode displacement, the vibration amplitude, and the vibration frequency can be varied as the workpiece is eroded, e.g. as conditions at the spark gap change.
[0028] According to the method, a single electrode may be presented to the workpiece. Alternatively, a plurality of electrodes may be simultaneously presented to the workpiece.
[0029] A second aspect of the present invention provides an electrical discharge machining apparatus including:
an elongate electrode, a drive mechanism which displaces the electrode relative to, in use, a workpiece, the displacement being in a direction aligned with the long axis of the electrode, and maintaining a spark gap between the electrode and the workpiece as the electrode wears and the workpiece is eroded by the electrode, a dielectric source which produces a dielectric fluid flow in the gap, and a vibration source which produces, simultaneously with the displacement, vibratory movement of the electrode, the vibratory movement being aligned with the long axis of the electrode.
[0034] Thus the apparatus is suitable for performing the method of the first aspect. Accordingly, the apparatus may have any one or, to the extent that they are compatible, any combination of the optional features corresponding to the optional features of the method of the first aspect. For example, the apparatus may have any one or, to the extent that they are compatible, any combination of the following optional features.
[0035] The electrode may have an axial bore, i.e. the electrode can be tubular.
[0036] The electrode can be rotated about its long axis.
[0037] The dielectric source may supply the dielectric fluid to the gap at a pressure of from 70 to 100 bar.
[0038] The vibration source can produce vibratory movement having a frequency of up to 500 Hz, and preferably of up to 250 or 200 Hz. The vibration source can produce vibratory movement having a frequency of more than 50 Hz, and preferably of more than 80 Hz. The vibration source can produce vibratory movement having a frequency of about 100 Hz.
[0039] Preferably, the drive mechanism and/or the vibration source has a frequency response of at least 1 kHz and more preferably of at least 10, 50 or 100 kHz.
[0040] The vibration source can produce vibratory movement having an amplitude of up to 200 microns, and preferably of up to 75 microns. The vibration source can produce vibratory movement having an amplitude of more than 20 microns. The vibration source can produce vibratory movement having an amplitude of about 50 microns.
[0041] Preferably, the vibration source produces a vibratory movement which is sinusoidal.
[0042] Conveniently, the apparatus can include one or more linear induction motors which provides both the drive mechanism and the vibration source, the linear induction motor being coupled to the electrode to displace the electrode relative to the workpiece, and to produce, simultaneously with the displacement, vibratory movement of the electrode. Advantageously, a linear induction motor can combine a high frequency response with high positional accuracy.
[0043] However, alternatively, the apparatus can include one or more linear actuators which provide the vibration source, the linear actuators being coupled to the electrode to produce the vibratory movement of the electrode. For example, the linear actuators can be piezo-electric actuators or pneumatic linear actuators. One option for such an arrangement is to operationally connect the one or more linear actuators to a reservoir for the dielectric fluid, such that, on activation of the actuators, pulsating jets of the fluid are sent from the reservoir to the spark gap simultaneously with the production of vibratory movement of the electrode. Conveniently, one or more linear actuators can be retrofitted to an existing electrical discharge machining apparatus to convert the apparatus into one according to the second aspect of the invention. The drive mechanism can include a lead-screw servomotor which is coupled to the electrode to displace the electrode relative to the workpiece. The one or more linear actuators may share with the servomotor the drive mechanism task of maintaining a spark gap between the electrode and the workpiece. For example, the linear actuators may displace the electrode up to a stroke limit of the actuators, whereupon the drive mechanism feeds the electrode to reset the actuators. This allows the apparatus to benefit from the high frequency response and high positional accuracy of a typical linear actuator. Thus, more generally, the one or more linear actuators may combine with a separate servomotor to provide the drive mechanism. Alternatively, the one or more linear actuators may be separate from the drive mechanism.
[0044] The apparatus may further include a tool holder which presents a single electrode. Alternatively, the apparatus may further include a tool holder which presents a plurality of electrodes to the workpiece.
[0045] In embodiments in which the dielectric source includes a reservoir for the dielectric fluid, the vibration source, on activation, can vibrate a piston that generates corresponding pressure pulses in the dielectric fluid of the reservoir, the axial bore of the electrode opening to the reservoir such that the pressure pulses produce the fluid jets. Conveniently, the electrode can then be connected to the piston such that the piston and electrode vibrate in unison. For example, when one or more linear actuators provide the vibration source, these can be connected to the piston by corresponding flexure joints. The connection to the piston can be direct, or indirect e.g. via a pressure cap and stopper arrangement. The electrode may enter the reservoir through an aperture in the cartridge, and preferably in the piston. The aperture may have a seal formation which grips the electrode and prevents leakage of dielectric fluid from the reservoir at the aperture. The seal formation may be configured such that its grip on the electrode is activated by the pressure of the dielectric fluid in the reservoir. For example, the seal formation may comprise a resilient body which is compressed (e.g. by the piston) into sealing engagement with the electrode under the action of the pressure of the dielectric fluid. When the apparatus includes a tool holder which presents a plurality of electrodes to the workpiece, the tool holder may include the piston (and the optional seal formation), which can then have a plurality of respective apertures for the electrodes. Indeed, more generally, the tool holder can take the form of a cartridge which also contains the reservoir. The piston is typically located at the lower end of the cartridge.
[0046] The apparatus may further include a computer-based control system for controlling the drive mechanism and the vibration source. The control system can be adapted such that any one or more of: the rate of the electrode displacement, the vibration amplitude, and the vibration frequency varies with electrode position. Typically, the apparatus further includes an electrical power supply which provides electrical power to the electrode, and a sensor which measures the spark gap. The control system can then also control the sparking frequency and the spark gap, and further can be adapted so that either of both of these parameters also varies with electrode position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which:
[0048] FIG. 1 schematically illustrates a typical HSEDM arrangement;
[0049] FIG. 2A shows at top an unworn electrode and at bottom a worn, tapered electrode, and FIG. 2B shows a bank of differentially worn electrodes;
[0050] FIG. 3 shows a section through a turbine blade with undesirable backwall erosion;
[0051] FIGS. 4A, 4B and 4C show schematically stages of the electrical discharge machining process with regard to erosion;
[0052] FIGS. 5A and 5B show schematically respectively front and side views of an HSEDM apparatus;
[0053] FIG. 6 shows schematically a spark gap control system for the apparatus of FIGS. 5A and 5B ;
[0054] FIGS. 7A, 7B, 7C and 7D show respective schematic cross-sections of workpieces and tubular electrodes during HSEDM drilling, the cross-sections in FIGS. 7A and 7C being without vibratory movement being applied to the electrodes, and the cross-sections in FIGS. 7B and 7D being with vibratory movement being applied to the electrodes;
[0055] FIGS. 8A and 8B show respective Design of Experiment interaction plots for drilling speed plotted against Servomotor Speed and Gap Voltage, in both cases with or without vibrations;
[0056] FIG. 9 shows typical plots of drilling depth against time obtained with and without vibratory movement being applied to an electrode;
[0057] FIGS. 10A and 10B show respective Design of Experiment interaction plots for cycle time plotted against peak current, and duty cycle , in both cases with or without vibrations;
[0058] FIGS. 11A and 11B show schematically respectively front and side views of another HSEDM apparatus;
[0059] FIGS. 12A and 12B shows schematically front views of respectively the tool holder and the vibration plate of the apparatus of FIGS. 11A and 11B ; and
[0060] FIG. 13 shows schematically a close-up front view of the lower end of the electrode cartridge and the pressure cap of the apparatus of FIGS. 11A and 11B .
DETAILED DESCRIPTION
[0061] Removal of debris during HSEDM is important in order to achieve appropriate machining speeds and consistency. Debris is removed by the dielectric flushing out debris in the time between the sparks. This process is shown schematically in FIGS. 4A-4C . A gas bubble, illustrated in FIG. 4A is generated by high temperatures as a result of spark discharge. This gas bubble then implodes as illustrated in FIG. 4B . The time between sparks, known as the “off time”, should be sufficiently long to allow dielectric fluid flushing to remove the debris. The off time determines the overall drilling cycle time for electric discharge machining. Lack of adequate debris removal therefore results in increased cycle times. Furthermore, poor debris removal increases electrode wear in the form of tapering. In FIG. 4A , as can be seen, an electrode 30 has a spark gap 31 to a workpiece surface 32 . During electrical discharge a spark-induced plasma channel 33 creates debris 34 from the workpiece surface as well as releasing some electrode debris 35 . Due to the heat of the spark, a bubble 36 is created within the high pressure dielectric fluid 37 .
[0062] As illustrated in FIG. 4B , during the off time the bubble 36 implodes, allowing the debris 34 , 35 to enter into the dielectric fluid flow 37 . During this off time, in addition to the debris, molten metal is partially removed from a spark generated crater 38 . Any molten metal that is not removed solidifies and becomes what is known as a recast layer. Such recast layers can have detrimental effects in terms of surface modifications of the material from which the workpiece is formed.
[0063] FIG. 4C illustrates the association between the workpiece 32 and the electrode 30 just prior to further electrical discharge machining. The debris 34 , 35 is held in suspension within the dielectric 37 and is therefore flushed away under the relatively high pressure provided by HSEDM. Progressively craters 38 are formed across the surface of the workpiece in order to erode and drill as required.
[0064] However, interruptions caused by inadequate removal of debris and consequent short circuiting can limit HSEDM effectiveness.
[0065] FIGS. 5A and 5B show schematically respectively front and side views of an HSEDM apparatus. The tool holder 106 for the electrodes 108 has been omitted from the front view (a) so that other components of the apparatus can be visualised.
[0066] A linear induction servomotor 101 is coupled to a head carriage 103 by means of a motor rod 102 . The head carriage is in turn mounted to a linear rail 115 (although in other embodiments, more than one linear rail may be used, or different types of linear guides can be employed, including linear air bearings). When the linear servomotor is activated, linear motion is thereby imposed on the head carriage.
[0067] An electrical connector 118 and a pneumatic chuck 104 are provided on the head carriage 103 . The connector 118 is connected to an electrical power supply (omitted in FIGS. 2A and 2B ) and transmits power across a mating connector 117 to a row of elongate tubular electrodes 108 mounted to a tool holder 106 . The pneumatic chuck 104 holds the tool holder to the head carriage under an electric signal command.
[0068] The tool holder 106 has an electrode cartridge 105 . A noseguide assembly 111 carrying a noseguide 110 is coupled to a static part 114 of the apparatus by means of a chuck 112 . The electrodes 108 and high-pressure dielectric fluid are contained within the electrode cartridge. The electrodes pass under clamps 107 , 109 and out through the noseguide. The clamp 107 is mounted beneath the electrode cartridge and consists of a bar, with a rubber pad, that is pneumatically applied to nip the electrodes during the drilling cycle. The clamp 109 is mounted on the noseguide assembly and consists of a bar, with rubber pad, that is pneumatically applied to nip the electrodes during the electrode reefed cycle.
[0069] Compressed air is supplied to clamps 107 , 109 through respective connectors 116 , 113 . High-pressure dielectric fluid is fed to the electrode cartridge 105 and the noseguide 110 through respective connectors 119 and 120 . Thus connectors 116 , 119 are on the head carriage 103 , while connectors 113 , 120 are on the static part 114 of the apparatus. The tubular electrodes are bathed in dielectric fluid in a reservoir contained within the electrode cartridge 105 so that the dielectric can flow both through and outside the electrodes. A high-pressure (e.g. 70-100 bars) pump (omitted in FIGS. 2A and 2B ) supplies dielectric fluid (e.g. deionised water) to the reservoir within the electrode cartridge 105 and thence to the machining spark gap between the electrodes and workpiece (e.g. blade) being drilled.
[0070] The linear induction servomotor 101 is capable of producing acceleration of up to 50 g in a mass of up to 10 Kg and can provide positional accuracy as small as 1 micron. In contrast to conventional rotary motors, linear induction motors convert electrical energy directly into linear movement, producing a straight-line force along the length of the motor. The linear servomotor is thus able simultaneously to displace the electrodes 108 in a direction aligned with their long axes to maintain the spark gap as the electrode wears and the workpiece is eroded, and to produce vibratory movement of the electrodes, the vibratory movement being aligned with the long axes of the electrodes.
[0071] A control system for the apparatus of FIGS. 5A and 5B is shown schematically in FIG. 6 . The linear servomotor 101 is controlled by a drive 121 , i.e. an electronic power amplifier that delivers the power required to operate the motor in response to low-level control signals supplied by a controller 122 which sets the motor motion parameters. A computer 123 is used to input the desired motion parameters including characteristics of a vibration sin wave 124 in terms of period (P) and amplitude (A), a displacement speed 125 (on which the sinusoidal vibration is superimposed) and a servo reference voltage 126 . The small diameter tubular electrodes 108 and the workpiece 127 are connected to an electrical power supply 128 , i.e. the EDM generator, which delivers periodic pulses of energy 129 to the spark gap 130 .
[0072] As machining occurs (i.e. high frequency sparks remove material from both electrodes 108 and workpiece 127 ), the linear servomotor 101 displaces the tool holder 106 to which the electrodes are mounted at the displacement speed 125 to keep constant the spark gap 130 between electrodes and workpiece. A meter 131 continuously measures the mean gap voltage, which is compared with the servo reference voltage 126 by a numerical control (NC) unit 132 . The tool holder 106 is moved downward if the mean gap voltage is higher than the reference voltage and upward when the mean gap voltage is lower than the reference voltage. The linear servomotor has a frequency response in excess of 1000 Hz, i.e. due to the dynamic characteristics of the linear servomotor and its control system, the servomotor can respond to changes in the spark gap within 0.001 sec.
[0073] Key process variables (such as frequency and amplitude of vibration, speed of displacement and EDM generator parameters) can be varied during the drilling process according to the depth of holes being drilled. This variation may be controlled by a program executed by the computer 123 , together with the NC unit 132 . An alternative approach that can be used to change key process variables during the drilling process is to use sensors to measure spark gap conditions in a closed-loop system e.g. combined with artificial intelligence techniques such as neural network or fuzzy logics. Such an approach could facilitate dynamic optimisation of the process variables.
[0074] The linear servomotor 101 can induce vibrations in the electrodes of up to 200 Hz with peak to peak amplitudes of up to 100 microns, and a resolution smaller than 0.1 microns. These vibrations induce corresponding vibrations in the dielectric fluid which can improve removal of debris from the spark gap. Furthermore, the servomotor positional accuracy of 1 micron facilitates accurate control of the spark. In addition, the high frequency vibration creates gaps between the electrode surfaces and the walls of the drilled hole which minimise the occurrence of arcing.
[0075] More specifically, cooling holes in turbine blades can have diameters as small as 0.38 mm and length-to-diameter-ratios of up to 80:1. The diameter of an electrode employed to drill 0.38 mm holes is usually 0.33 mm. If there is a requirement to drill a hole with diameter of 0.38 mm and length of 30 mm, the distance from the tip of the electrode to the noseguide will be 30 mm at hole breakthrough. Such a slender electrode can tend to tilt and touch the sidewall of the hole during the drilling process, provoking short-circuits and process interruption. Another problem associated with the drilling of deep holes with small diameters is the removal of debris from the spark gap. This can be difficult even when high-pressure dielectric fluid (of up to 100 bars) is employed. The accumulation of debris can provoke arcing and increase cycle times. These problems become more critical when multi-electrode drilling operations are carried out, as the apparatus has just one servomotor to control a plurality of spark gaps.
[0076] FIGS. 7A-7D show respective schematic cross-sections of workpieces 205 and tubular electrodes 202 during HSEDM drilling. The workpieces are drilled using multi-electrode tools 203 and high-pressure (70 to 100 bars) dielectric fluid 201 supplied to the bore of the electrodes from the electrode cartridge (omitted). High frequency sparks 207 , in the order of 100 kHz, promote material removal both from electrodes and especially from the workpieces.
[0077] FIGS. 7A is an example of the process without vibratory movement being applied to the electrodes 202 . The resultant debris 206 from the process tends to accumulate in the spark gap and in the lower end of the holes as the dielectric pressure is insufficient to flush the debris out in the exiting flow 204 . The accumulation of debris can result in arcing, which damages the workpiece and increases cycle times. However, when axially aligned vibrations 210 are applied to the electrodes, as shown in FIG. 7B , the oscillating electrodes and holes being drilled act like reciprocating pumps in which the electrodes are the pistons and holes are the cylinders. The vibratory movement of the electrodes at a frequency of up to 500 Hz and peak to peak amplitude of up to 100 microns pumps the dielectric fluid 212 and debris out of the spark gap and the holes. Thus the pumping action improves flushing 211 , and can be increased further when the vibrations are combined with pulsating jets 209 of dielectric fluid sent to the spark gap through the axial bore of the electrode, the jet pulsations along the bore of the electrode having the same frequency as the electrode vibratory movement. An HSEDM apparatus which produces such synchronised pulsating jets is described below in relation to FIGS. 10A-12B .
[0078] FIG. 7C is another example of the process without vibratory movement being applied to the electrodes 202 . The tubular electrodes 202 tend to form cores 208 of workpiece material that remain uncut in the centres of the holes being drilled. Such a core may tilt and touch 213 the internal wall of the electrode, provoking short-circuits. In addition, the slender electrodes can move sideways 214 and touch the sidewall of the holes being drilled, again provoking short-circuits. Such short-circuits cause servo retraction and consequently lead to longer machining times or to process interruptions. Moreover, the short-circuits can damage the workpiece. However, when axially aligned vibrations 210 are applied to the electrodes, as shown in FIG. 7D , small gaps 215 , 216 can be more easily maintained between the cores and electrode bore, and between the electrode outer surface and the hole sidewall. These gaps result from damage caused by the vibrations to the roughness asperities on the surfaces of the electrodes and the workpiece, the asperities being the channels for electrical current flow between the electrodes and the workpiece.
[0079] Thus the vibration of the electrodes improves flushing and reduces short-circuits, and, as a result, the servomotor can move downwards at faster speeds.
[0080] Drilling trials were carried out using a multi-electrode tool with capacity to hold 18 tubular electrodes. The diameter of the electrodes was 0.31 mm and these were used to cut (in a single pass) 18 holes with a length of 4 mm. A Design of Experiments fractional factorial approach was used to perform the experiments and analyse the results. The factors used in the design are shown in the table below. The factor “Vibration” refers to the vibration produced in the electrode. The lower level (−1) of vibrations means that tests were carried out without vibrations, whereas the higher level (+1) means that the tests were carried out with vibrations. “Servomotor Speed” refers to the velocity with which the servomotor advances to keep the spark gap constant. “Gap Voltage” refers to the reference voltage, which is proportional to the spark gap size, i.e. a Gap Voltage at the higher level means that the size of the spark gap is higher than at the lower level.
[0000]
LEVEL
FACTOR
I
II
Vibration
−1
+1
Servomotor Speed
−1
+1
Gap Voltage
−1
+1
[0081] FIGS. 8A and 8B show interaction plots of the experimental parameters, i.e. drilling speed plotted again (a) Servomotor Speed and (b) Gap Voltage for the different vibration levels. When vibrations are produced in the electrodes (dotted lines), smaller cycle times are achieved with the servomotor speed at the lower level. In contrast, the higher servo speed decreased the cycle time when the vibrations were turned off. As to gap voltage, when trials were carried out without vibrations, changing the value of the gap voltage did not affect cycle times. In contrast, gap voltage had to be set at the higher level in order to reduce cycle times with electrode vibrations. When vibrations are applied to the electrodes, a higher spark gap size helps the electrode oscillations to remove debris from the spark gap.
[0082] FIG. 9 shows typical plots of drilling depth against time obtained with and without vibrations. Reductions in cycle times of nearly 50% can be achieved if vibrations are applied to the electrodes.
[0083] Further drilling trials were carried out to produce additional interaction plots. FIG. 10A shows plots of cycle time (i.e. time to drill a given hole depth) against peak current (+1=high peak current, −1=low peak current) for tests carried out with (+1) or without (−1) vibrations. HSEDM drilling assisted by vibrations is faster when compared with drilling that is not assisted by vibrations. However, the impact of vibrations is more significant when higher levels of peak current are employed. FIG. 10B shows plots of cycle time against duty cycle (+1=high duty cycle, −1=low duty cycle) for tests carried out with (+1) or without (−1) vibrations, duty cycle being the ratio of the sparking time to the length of time required for one complete sparking cycle (i.e. the time for sparking to take place and then for implosion of the gas bubble and removal of debris before the next sparking event). The impact of vibration becomes very significant for high levels of duty cycle, but is negligible at low levels of duty cycle.
[0084] The HSEDM apparatus described with reference to FIGS. 5A and 5B has a linear induction servomotor which both displaces the electrodes to maintain the spark gap and produces the vibratory movement of the electrodes. However, other configurations are possible, e.g. in which the displacement and vibration functions are driven by different parts of the apparatus. For example, FIGS. 11A and 11B show schematically respectively front and side views of an HSEDM apparatus in which a lead-screw servomotor drives the electrode displacement and separate piezo-electric or pneumatic linear actuators drive the electrode vibration. The servomotor 301 has a coupling 302 to a lead-screw 303 that turns the servo rotation into linear motion of a head carriage 304 .
[0085] An electrical connector 321 and a pneumatic chuck 305 are provided on the head carriage 304 . The electrical connector is connected to an electrical power supply (omitted in FIGS. 11A and 11B ) and transmits power across a mating connector 320 to tubular electrodes 311 mounted to a tool holder 308 . The pneumatic chuck holds the tool holder to the head carriage under an electric signal command.
[0086] The tool holder 308 has an electrode cartridge 307 . A noseguide assembly 314 carrying a static noseguide 313 is coupled to a static part 317 of the apparatus by means of a chuck 315 . The electrodes 311 and high-pressure dielectric fluid are contained within the electrode cartridge. The electrodes pass under clamps 310 , 312 and out through the noseguide. The clamp 310 is mounted beneath the electrode cartridge and consists of a bar, with rubber pad, that is pneumatically applied to nip the electrodes during the drilling cycle. The clamp 312 is mounted on the noseguide assembly and consists of a bar, with rubber pad, that is pneumatically applied to nip the electrodes during the electrode reefed cycle.
[0087] Compressed air is supplied to clamps 310 , 312 through connectors 319 , 316 . High-pressure dielectric fluid is fed to the electrode cartridge 307 and the noseguide 313 through connectors omitted in FIGS. 11A and 11B .
[0088] Two linear actuators 322 are assembled in a vibration plate 306 mounted to the tool holder 308 (in other embodiments only one linear actuator, or more than two linear actuators can be employed). FIGS. 12A and 12B show schematically front views of respectively the tool holder and the vibration plate. The vibration plate has flexure joints 323 . The electrode cartridge 307 is attached to a static section 324 of the vibration plate, while a pressure cap 309 and the clamp 310 are attached to a moving section 325 of the vibration plate. The pressure cap contains a rubber seal 326 and a plastic stopper 327 . A piston 328 is mounted at the lower end of the electrode cartridge above the seal and the stopper, with a seal ring 329 fluidly sealing the piston to the static section of the vibration plate. The piston, the seal and the stopper contain matching rows of holes through which the electrodes 311 are passed.
[0089] FIG. 13 shows schematically a close-up front view of the lower end of the electrode cartridge 307 and the pressure cap 309 . Just before the start of the drilling process the electrodes 311 are clamped by the clamp 310 and dielectric fluid 330 at a pressure ranging from 70 to 100 bars is supplied to a fluid reservoir defined within the electrode cartridge. The high-pressure fluid in the reservoir provokes a movement of the piston 328 , which squeezes the seal 326 against the stopper 327 . As a result, the holes in the seal reduce in size, gripping the electrodes and sealing the electrode cartridge. A flow 331 of dielectric is supplied to the spark gaps through the bores of the electrodes and through flushing holes (omitted from FIGS. 11A to 13 ) in the noseguide.
[0090] The linear actuators 322 produce oscillations 332 in the moving section 325 of the vibration plate 306 , where the pressure cap 309 and clamp 310 are mounted. The movement of the vibration plate induces vibrations (with frequencies of up to 500 Hz and peak-to peak amplitude up to 100 microns) in the electrodes 311 . Moreover, the oscillations of the pressure cap 309 induce pressure pulses in the dielectric fluid 330 contained in the reservoir of the electrode cartridge 307 . These pressure pulses produce high frequency pulsating jets 333 of dielectric fluid that are supplied to the spark gaps via the bores of the electrodes. Advantageously, the combined effects of the pumping action provided by electrode oscillations and the high frequency pulses of the dielectric jets greatly improve the flushing of debris from the spark gaps. Furthermore, the use of separate linear actuators to drive the electrode vibration facilitates the retrofitting of such actuators onto existing HSEDM apparatuses.
[0091] A disadvantage of lead-screw servomotors is their typically low frequency response of about 30 Hz, which is not fast enough to respond to rapid changes to the spark gap. It is possible to increase the frequency response of lead-screw servos by increasing the pitch and/or rotational speed. However, this affects the positional resolution of the electrodes. Moreover, too high rotational speeds can cause the screw to whip or hit a resonant frequency causing uncontrolled vibrations and wild instability. However, by retrofitting a lead-screw servomotor with one or more linear actuators to drive electrode vibrations, the low frequency response can be side-stepped such that the retrofitted apparatus can be made to provide high frequency vibratory movement of the electrodes simultaneously with their displacement to maintain the spark gap. Also the dielectric fluid can be made to issue from the bores of the electrodes into the spark gaps as pulsed jets synchronised with the electrode vibration to further enhance debris removal.
[0092] However, if screw resonance and whip can be avoided, by using e.g. appropriate software it is nonetheless possible to control a lead-screw servomotor to produce electrode vibrations superimposed on the linear motion of the electrodes without the use of additional linear actuators. Although the response time of such an arrangement will be relatively low, some benefits can be obtained, such as the ability to produce pulsating jets of dielectric fluid and improved removal of debris through a dielectric fluid pumping action.
[0093] The apparatus of FIGS. 11A to 13 can be controlled by the control system shown in FIG. 6 .
[0094] In an operational variant, the task of keeping constant the size of the spark gap can be shared between the linear actuators 322 and the lead-screw servomotor 301 . More specifically, the linear actuators provide high positional precision and a high frequency response, but only allow a maximum stroke about 200 microns. Thus, as well as vibrating the electrodes 311 , the actuators can be used to displace the electrodes to keep the spark gap constant up to the stroke limit of the actuators, whereupon the lead-screw servomotor re-feeds the electrodes. Indeed, a variant apparatus can have one or more linear actuators to provide electrode vibration and displacement, and a linear induction servomotor instead of a lead-screw servomotor to re-feed the electrodes.
[0095] While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when given this disclosure. For example, an apparatus can have just one electrode. Another type of electrode tool holder can produce electrode rotation during the drilling process. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.
[0096] All references referred to above are hereby incorporated by reference.
|
A method for electrical discharge machining a workpiece includes the steps of: presenting an elongate electrode to the workpiece with a spark gap therebetween; flowing a dielectric fluid in the gap; eroding the workpiece by electrical discharge between the tip of the electrode and the workpiece; displacing the electrode in a direction aligned with the long axis of the electrode to maintain the gap as the electrode wears and the workpiece is eroded; and simultaneously with the displacement, producing vibratory movement of the electrode, the vibratory movement being aligned with the long axis of the electrode.
| 1
|
FIELD OF THE INVENTION
The present invention claims priority from U.S. provisional patent application No. 60/171,842, filed Dec. 22, 1999 and titled HOLE PATCHING DEVICE & METHOD OF USE. The present invention relates to devices for patching holes and more specifically devices for patching holes in a wall.
BACKGROUND OF THE INVENTION
Modern homes generally include wall coverings of plywood, drywall or other such material secured to studs. These materials, while strong, do become damaged typically in the form of a hole. One common method that causes holes is opening a door too far and sending the opposing door knob into and occasionally completely through the adjacent wall. Holes are considered unattractive, unsightly and generally undesired.
Previously, home owners could fix these holes in a couple manners. In one method, the home owner would cut a large square or rectangular block of drywall out of the wall. The block would extend half way across the adjacent wall studs. A new piece of drywall with similar dimensions of the now enlarged opening is cut and secured inside the opening. The wall is then taped and plastered in the manner used in original construction. This method is time consuming, messy and exceeds the abilities of most home owners, requiring the services of a professional.
In an alternate method, a variety of strips of wood are cut with a length longer than the diameter of the opening and a width narrower. The pieces of wood are tied to a string and inserted into the opening. The string is held taught and the wood stripes are fanned out across the back of the hole. The hole is then filed with plaster, smoothed and sanded. This method requires substantial coordination and time and has a poorly secured backside to the now filled hole.
What is needed is a device and method of repairing a hole in a wall that is simplistic enough to allow the average home owner to repair the hole. The process should be fast, solid, requiring a minimum amount of time and talent to accomplish the task with professional results.
SUMMARY
The present invention includes a device for repairing a hole in a wall. The device includes a cover for an opening that secures on an interior surface of a wall. The cover is preferably formed of a generally rigid material and is at least two inches in diameter. The device includes a guide for directing the cover through the opening, which preferably is a slit cut from a center of the cover to an outer edge of the cover. The device further provides a securement mechanism for joining the cover to the interior surface of the wall, where it together with the edges of the hole defines a pocket. An insert is placed in the pocket to substantially fill the same. A hardenable material, such as plaster, spreads over the insert and pocket, where it is smoothed with the wall.
This device may have additional components that augment the invention. For instance, the securement mechanism may include a temporary and a permanent portion. Temporary securement may be done with a t-bar together with a wedge or a cord and stop. These hold the cover to the wall while adhesive permanently attaches the cover to the wall. Once permanent securement is complete the temporary securement portions may be removed in whole or in part. The wedge may be designed to include a cutting edge, e.g., saw for cutting smooth edges to the hole and other modifications are made apparent with the description herein.
The present invention also includes a method of repairing a hole. The inventive steps include guiding a cover through an opening using a slit extending from a center of the cover to an outer edge of the cover. This may be done in a cork screw type manner. Next, one secures the cover to an interior surface of a wall to define a pocket. The pocket does not need to be filled with plaster, which tends to shrink upon drying. Instead, one may insert a plug to substantially fill the pocket and then apply a hardenable material over the insert and pocket such as plaster. This process may be augmented with other steps, which may for instance include adhesively securing the cover to the interior surface of the wall. Additionally, the cover may be temporarily secured to the interior of the wall using a t-bar and wedge.
DESCRIPTION OF THE FIGURES
FIG. 1 shows the present invention installed on a wall;
FIG. 2 shows an embodiment of the present invention;
FIG. 3 shows the covering mechanism; and
FIG. 4 shows the preferred embodiment of the present invention.
DETAILED DESCRIPTION
The present invention 10 , shown in FIGS. 1-4, is the preferred embodiment of the present invention. The present invention is preferably for the purpose of patching holes 12 in walls 14 , such as drywall, although one using the drawings and description can easily find many other uses for the present invention. Hole 12 and opening 12 are used interchangably throughout the specification with both referencing a hole through a wall. The present invention 10 may include, mechanism 16 for covering the opening 12 on an interior surface 18 of the wall 14 , mechanism 20 for guiding the covering mechanism 16 through the opening 12 , and mechanism 22 for securing the covering mechanism 16 to the interior surface 18 of the wall 14 , creating a pocket 15 and mechanism 17 for filling the pocket 15 . Each mechanism and the operation,is described further below.
The covering mechanism 16 may be any size or shape suitable for substantially covering the opening 12 in the wall 14 . Small gaps may be present, the size of which need to be small enough to allow effective plastering of the covered hole 12 as described in the operation section below. The preferred shape of the covering mechanism is circular as this is believed to be the most common shape of a hole 12 in a wall 14 .
The covering mechanism 16 preferably may cover holes 12 that are an inch in diameter to the size of the largest holes. Commonly holes 12 range from about 3 inches to about 5 inches in diameter, although larger and smaller holes are found. The covering mechanism preferably is about two or more inches in diameter larger than the opening 12 such that at least a one inch perimeter 24 (FIG. 1) is obtained around the circumference of the holes 12 , although a smaller perimeter 24 may be used. The perimeter 24 prevents the covering mechanism 16 from being pulled back through the opening 12 .
The covering mechanism 16 may be formed of any sufficiently rigid material for the purpose intended. The material needs to provide a firm surface without substantial bowing into the opening, but preferably provides some flexibility for working the covering mechanism 16 through the opening 12 . Suitable materials include, metals, substantially rigid plastics, substantially rigid elastomers, wood, ceramic, and any other substantially rigid material. The preferred material for the covering mechanism 16 is a substantially rigid plastic due to its cost and ease of use.
The guiding mechanism 20 may be any mode of changing the size of the profile of the covering mechanism 16 without damaging the covering mechanism 16 . The preferred mode, shown best in FIG. 1, includes an opening 26 defined in the approximate center of the changing mechanism 16 and a cut 28 , extending from the hole 26 to the outer edge 30 of the changing mechanism 16 . When the opposing edges 32 , 34 are spread, one can plainly see that the profile of the changing mechanism can be corkscrewed through an opening that is approximately the size to the width of the changing mechanism, preferably a half inch or less, by approximately half the diameter of the changing mechanism 16 .
The securing mechanism 22 may include string or other cord-like material 36 and stop 38 . Preferably, the securing mechanism 22 is a t-bar 21 with or without a wedge 23 . The wedge 23 passes through slot 25 of the t-bar 21 and biases against the edges of the opening to be filled to draw the covering mechanism 16 tight against the wall 14 . The wedge 23 may have a serrated edge 27 for cutting a clean opening in the wall 14 .
The stop 38 is preferably of a size larger than the opening 26 such that when the string 36 is pulled through the opening 26 the stop will brace against the perimeter of the opening 26 . The opening 26 may be of any suitable size, but is preferably about one inch in diameter. The stop may be of any size or shape so long as it secures against the perimeter of the opening 26 and does not extend beyond the outer surface of the wall 14 and into the room. The string 36 and stop 38 combination also provides a mechanism for retrieving the, invention 10 should it drop down inside the wall 14 . The mechanism 22 may further include a ring of adhesive 40 for adhering the covering mechanism 16 to an interior surface of a wall 14 . The securing mechanism 22 holds the covering mechanism 16 in position covering the opening 12 , creating a pocket 15 between the covering mechanism 16 and the sides of the opening 12 .
The opening 12 in a preferred embodiment is a circular or other common shape. The circle may be drawn on the exterior surface of the wall 14 with a stencil and then cut with a keyhole saw, serrated edge 27 of the wedge 23 or like implement. A filling mechanism 17 may then be positioned to substantially fill the pocket 15 . The filing mechanism 17 may be any material which substantially fills and does not require substantial drying or hardening time. While various foams could be used, the preferred filling mechanism 17 is a plug 19 formed of preformed foam, wood or other solid material. Once the filling mechanism 17 is in place, the installer may cover the hole with plaster and paint.
In operation, the opening 12 may be widened into a circular or other common shape, perhaps through a stencil and cutting process. The cutting may be done with the serrated edge 27 of the wedge 23 . The string 36 or t-bar 21 is fed through the opening 26 of the covering mechanism 16 for later use. The covering mechanism 16 is spread along the guiding mechanism 20 , changing the profile of the covering mechanism 16 to a dimension smaller than the opening 12 . The configuration is similar to the letter “c” twisted along its central axis. An opposing edge 32 or 34 is fed through the opening 12 . The covering mechanism 16 may then be corkscrewed into the wall 14 . Once inside, the installer manipulates the string 36 or t-bar 21 and stop 38 combination to hold the covering mechanism 16 in a desired location. Adhesive 40 may be uncovered (if preapplied) or applied to further provide securement of the covering mechanism 16 about the opening 12 on the interior surface of the wall 14 . The best adhesive 40 which has been found is sold under the trade name “Liquid Names,” due to the absorption of the adhesive 40 prior to the adhesive 40 setting up. A wedge 23 may be fed through slot 25 in the t-bar 21 and biased against the wall 14 to secure the covering mechanism 16 in place while the adhesive dries. Screws or other fasteners may also be used to hold the covering mechanism 16 in place.
The wedge 23 may be removed and t-bar 21 may be broken, pushed into the interior wall or otherwise vacated, when the adhesive or other permanent fastener has taken hold, assuming a wedge 23 and t-bar 21 were used. This configuration defines a pocket 15 between the edges of the hole 12 in the wall 14 and the covering mechanism 16 . The pocket 15 is filled with a plug 19 , plaster, wood filler, putty, other filling material or combination thereof. The string 36 , no longer needed, may be clipped, the filler material smoothed and the wall 14 painted or otherwise decorated.
It will be appreciated that the foregoing description of the preferred embodiment of the invention is presented by way of illustration only, and not by way of any limitation. It should be noted that use of appropriate materials would allow the present invention to be used for patching of holes in automobile walls and automotive bumper walls or other areas. Various alternatives and modifications may therefore be made to the above mentioned and illustrated embodiments without departing from the spirit and scope of the present invention.
|
A hole patching device including mechanism for covering an opening on an interior surface of a wall, the covering mechanism being formed of a generally rigid material and being at least two inches in diameter; mechanism for guiding the covering mechanism through the opening, which may include a slit cut from a center of the covering mechanism to an outer edge of the covering mechanism; mechanism for securing the covering mechanism to the interior surface of the wall to define a pocket; an insert for filling the pocket; and a hardenable material spread over the insert and pocket smoothable with the wall and a method of use.
| 4
|
The invention relates to a drive module; in particular, the invention relates to a drive module for a fan in a motor vehicle.
Drive modules are standardized assemblies which can be handled separately and can be used universally. One field of use of a drive module of this type is a fan system in a motor vehicle, in which a fan is arranged between an intake section for fresh air and a distributor section for delivered air. A fan of this type can be constructed with the aid of a drive module, with the result that an installation and dismantling time of the fan is minimized and, in addition, accessibility of components which are situated in the adjacent sections, for example of a heat exchanger or a heater, is improved.
In drive modules in general and in a drive module for use in a fan, in particular, decoupling of the drive motor from its surroundings with regard to vibrations of every type is frequently required, in order to minimize solid-borne sound and vibrations which fatigue material. Elastic decoupling elements are usually used for decoupling purposes, such as steel springs. Usual decoupling requires additional installation space, for instance in the axial direction of a side facing the output or in a radial direction of the drive module. As a consequence of this, the resulting drive module is larger and less flexible in terms of its use.
SUMMARY OF THE INVENTION
The invention is based on the object of specifying an arrangement of vibration-damping decoupling elements on a drive module, which arrangement is advantageous with regard to function and installation space.
According to a first aspect, a drive module, in particular for a fan in a motor vehicle, comprises a drive motor with a stator, at least one vibration-damping decoupling element, and a fastening flange which is connected via the decoupling element to the stator of the drive motor, the decoupling element being arranged in the interior of the stator and the fastening flange having a supporting element which is in engagement with the decoupling element.
As a result, positioning of the decoupling elements in the axial direction behind the drive motor or radially outside the drive motor can be avoided, as a result of which the drive module can be of more compact construction.
A plurality of decoupling elements can be arranged radially symmetrically about the rotational axis of the drive motor along a circumference. As a result, a space within the stator can be used advantageously, which space would otherwise not be usable for components of the drive module. As a result of the given arrangement, the guidance of a concentric shaft or axle of the drive motor is not impaired.
The decoupling element can be configured as a hollow cylinder which comprises a radial inner face which is in engagement with the supporting element and a radial outer face which is in engagement with the stator. For example, the decoupling element can be configured in the form of an elongate sleeve, with the result that it can also transmit comparatively great forces, as can occur, for example, in the case of a small spacing of the decoupling elements from the rotational axis of the drive motor.
The stator can comprise a first and a second holder, each holder mounting the decoupling element in an axial direction. The decoupling element can thus already be fixed permanently on the stator before the latter is fastened to the fastening flange. In addition, the decoupling element can be configured in such a way that it is connected to the two holders of the stator by means of a frictional connection, with the result that handling of the stator in the context of a production process is simplified. In addition, each holder can bear in the radial direction against the decoupling element.
On a side which faces the fastening flange, the supporting element can have a shoulder which bears axially against the decoupling element. As a result, a minimum spacing can be defined between the stator and the fastening flange.
On a side which faces away from the fastening flange, the supporting element can carry a securing element which bears axially against the decoupling elements. The securing element can ensure rapid single-use mounting. As a result, for example, the stator which comprises the decoupling element can be pushed in a single work operation onto the axial supporting element of the fastening flange and can be secured there on the supporting element by way of a securing element. This arrangement also permits decoupling of vibrations of the stator from the fastening flange in the axial direction.
The stator can be enclosed by a rotor of the drive motor. In an arrangement of this type with outer rotor, a particularly highly integrated drive module can be realized as a result of the given arrangement of the decoupling elements on the inner side of the stator.
The fastening flange can define an outer contour of the drive module in the radial direction. As a result, a section of the drive module can be introduced through a fixing or mounting opening of a fastening structure in such a way that the fastening flange subsequently closes the opening and mounts the drive module in the opening. The fastening flange can have further elements, in order, for example, to form a closure with the surrounding structure or an airtight or watertight closure with regard to this structure, for instance a seal, a supporting ring and/or locking elements. Moreover, the fastening flange can comprise, for example, an electric connector element for the drive motor, for example a plug or a socket.
According to a second aspect, a fan module comprises a drive module with a drive motor with outer rotor and a fan wheel which is connected to the outer rotor. The fan wheel can be formed in such a way that the drive motor largely fills the space which is defined by the fan wheel, with the result that the fan module is particularly compact. In particular, the fan wheel can have a semi-axial construction with a concave boundary which faces the drive motor.
According to a third aspect, a motor vehicle comprises a fan system having the fan module as described above. The particularly compact construction of the fan module results, for example, in a greater structural scope for other elements of the motor vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following text, the invention will be described in greater detail with reference to the appended drawings, in which:
FIG. 1 shows a diagrammatic illustration of a fan system in a motor vehicle;
FIG. 2 shows an isometric view of an exploded illustration of part of the drive module from FIG. 1 ;
FIG. 3 shows a sectional view of the mounted part from FIG. 2 ; and
FIG. 4 shows a sectional view of a fan module using the mounted part from FIG. 3 .
DETAILED DESCRIPTION
FIG. 1 shows a diagrammatic illustration of a motor vehicle fan system 100 . A motor vehicle 110 comprises an intake section 120 , a fan module 130 and a distributor section 140 . The fan module 130 comprises a fan wheel 150 and a drive module 160 . Optional elements of the motor vehicle fan system 100 are not contained in the illustration of FIG. 1 , such as filters, flaps, valves, heat exchangers, condensers and the like which are not further relevant in the present context. The drive module 160 sets the fan wheel 150 in rotation, with the result that air is sucked into the fan wheel 150 from an outer side of the motor vehicle 110 through the intake section 120 and is subsequently conveyed through the distributor section 140 to the inside of the motor vehicle 140 . A use of the fan module 130 in a ventilation system outside a motor vehicle 110 is likewise possible.
The intake section 120 and the distributor section 140 are frequently configured jointly in a common section. The fan module 130 can be capable of being inserted into the intake section 120 , the distributor section 140 or the integrated section in the manner of a cartridge. In the surroundings of the fan module 130 , the relevant section can have an element which converts a radial flow direction of air which flows out of the fan wheel 150 into a linear flow direction, for example a pressure increasing spiral which additionally brakes and compresses the air which flows away from the fan wheel 150 .
FIG. 2 shows an isometric illustration of an exploded drawing of a part 200 of the drive module 160 . The part 200 which is shown comprises a fastening flange 205 with four axial supporting elements 210 and a stator 220 which can be coupled to the fastening flange 205 by means of four elastic decoupling elements 215 . The decoupling elements 215 are composed of an elastic material which preferably has high internal damping, for example silicone or rubber. The stator 220 comprises a first holder 225 and a second holder 230 , a first magnetic flux element 235 , a lower rotary bearing 240 , an upper rotary bearing 245 and securing elements 250 . The supporting elements 210 have shoulders 260 .
The stator 220 is configured in such a way that it can be mounted on the fastening flange 205 as a unit which can be handled separately. To this end, the first flux element 235 and the four decoupling elements 215 are inserted between the first holder 225 and the second holder 230 at the correspondingly provided positions, before the first holder 225 is connected to the second holder 230 . When the first holder 225 and the second holder 230 are connected to one another, the decoupling elements 215 and the first flux element 235 are delimited in each case in the axial direction on both sides by the two holders 225 and 230 . A clamping action which fixes the two holders 225 and 230 against one another is induced by a frictional connection between the outer circumference of the decoupling elements 215 and the corresponding radial receptacles of the lower holder 225 and the upper holder 230 . Furthermore, there is a frictional connection between the inner circumference of the first magnetic flux element 235 and the holders 225 and 230 . Fixed in this way, a winding (or coils) can be applied to the stator 220 , which winding comprises a number of conductor sections which extend in the axial direction along the circumferences of the holders 225 and 230 . These wire pieces can be fixed by means of the projections of the holders 225 and 230 , which projections extend in the axial direction. Together with the first magnetic flux element 235 (also called short-circuit plate or flux plate), the windings can form coils or electromagnets for magnetic coupling to a rotor which encloses the stator 220 .
The lower rotary bearing 240 and the upper rotary bearing 245 are connected in a rotationally stable manner to the first holder 225 and the second holder 230 and are configured for receiving an axle or shaft which is connected to the stator. In an alternative embodiment, one or both of the bearings 240 and 245 can also be of rotatable configuration with regard to the holders 225 , 230 which surround them.
FIG. 3 shows a lateral sectional view of the mounted part 200 of the drive module 160 from FIG. 2 . The lower rotary bearing 240 and the upper rotary bearing 245 are not shown. The approximately hollow-cylindrical decoupling elements 215 bear on their inner circumference in a positively locking manner against the supporting elements 210 . The decoupling elements 215 are fixed in the axial direction downward by shoulders 260 in the axial supporting elements 210 and upward by means of the securing elements 250 on the supporting elements 210 . The securing elements 250 can be, for example, self-locking securing rings. As an alternative to this, the securing elements 250 can be pressed, for example, onto an end section of the supporting element 210 or the latter can be fit into them. To this end, the end sections of the supporting elements 210 can be shaped conically. In a further embodiment, the securing elements 250 are connected non-positively to the supporting elements 210 , for example, by means of adhesive bonding, welding, remelting, brazing, screwing or a further known connection method.
The decoupling element 215 has in each case coaxial recesses on its two end faces in the axial direction, into which coaxial recesses hollow-cylindrical engagement elements of the first holder 225 and the second holder 230 of the stator 220 engage, with the result that the decoupling element 215 is fixed both in the radial and in the axial direction with respect to the stator 220 .
The axial supporting element 210 is configured in one piece with the fastening flange 205 , a multiple-piece construction also being possible in an alternative embodiment. The supporting element 210 has a radial spacing from the first holder 225 . The magnitude of the spacing defines a maximum compression travel of the decoupling element 215 when the stator 220 is deflected with respect to the fastening flange 205 . A great spacing also assists absorption of pronounced vibrations, but at the same time allows a relatively great deflection of the stator 220 with respect to the fastening flange 205 , with the result that the position of the stator or of an element which is connected to it is defined less precisely.
The radial contact of the securing element 250 with the second holder 230 of the stator 220 is optional. The first magnetic flux element 235 is formed by a number of rings made from a softly magnetic material which are stacked on one another. Alternative embodiments, for example in the form of a single-piece or multiple-piece cylinder or a spiral, are likewise possible.
FIG. 4 shows a lateral sectional view of a fan module 130 using the drive module 160 of FIG. 1 which comprises the part 200 of FIGS. 2 and 3 . In addition to the drive module 160 , the fan module 130 comprises a fan wheel 410 , permanent magnets 420 , a second magnetic flux element 430 and an axle 440 . In the selected illustration, the supporting elements 210 and the elastic decoupling elements 215 are shown from outside, that is to say in a non-sectioned state. For the sake of clarity, no coils are shown on the stator 220 either. The fan module 160 is universally suitable for use in fan systems 120 , 130 , 140 , the high space utilization with simultaneously satisfactory vibration damping particularly favoring use in a motor vehicle 110 .
The fan wheel 410 is of the semi-axial type, that is to say it comprises fan blades for sucking in air from the axial direction (from the left) and fan blades for discharging the air which has been sucked in the radial direction. The fan wheel 410 is connected to the drive module 160 by means of the axle 440 . The axle 440 is fastened fixedly to the fan wheel 410 so as to rotate with it, for example by being molded on, being cast on, being pressed in, being adhesively bonded, being welded or being fit. A rotor 400 of the drive module 160 is formed by the permanent magnets 420 and the second magnetic flux element 430 which are attached fixedly to the fan wheel 410 so as to rotate with it. The second magnetic flux element 430 produces a magnetic flux on an outer circumference of the permanent magnets 420 which are arranged in the manner of a ring.
The axle 440 can be secured at its end which faces the fastening flange 205 against sliding out of the lower rotary bearing 240 . This securing means can be accessible, for example, by a corresponding mounting opening (not shown) in the fastening flange 205 , in order for it to be possible to disconnect the fan wheel 410 from the drive module 200 as required. As an alternative to this, the axle 440 can be secured in the axial direction by means of a non-releasable connection against sliding out of the lower rotary bearing 240 , for example by means of a securing ring which has been pressed on or fit, a circlip or another element with a comparable effect.
The fastening flange 205 is dimensioned in such a way that, on its right hand side, it fills a mounting opening, through which the fan wheel 410 can pass. The mounting opening can be situated on an air section of the motor vehicle 110 from FIG. 1 and can be, for example, circular.
|
The invention relates to a drive module, particularly for a fan in a motor vehicle, comprising a drive motor having a stator, at least one vibration-dampening decoupling element, and a fastening flange connected to the stator of the drive motor by the decoupling element, wherein the decoupling element is arranged in the interior of the stator and the fastening flange comprises a supporting element that is engaged in the decoupling element.
| 5
|
RELATED APPLICATIONS
[0001] This application is a divisional of copending application Ser. No. 11/360,434 filed on Feb. 24, 2006.
BACKGROUND OF THE INVENTION
[0002] Some structures are designed with a higher than usual level of safety against partial or complete failure due to their functions and the disastrous consequences of their structural disintegration. However, many of such structures have been designed and built without considering some of the very high impactive or impulsive loads on the assumption that the probabilities of occurrence of such loads are extremely low. As time elapses, the changing circumstances of the world may render this probabilistic assessment obsolete and the probabilities of occurrence of such hazards become non-negligible. As an example of having structures subjected to unexpected hazards is the terrorist attack of Sep. 11, 2001, where three aircrafts crashed upon the two towers of the World Trade Center and the Pentagon building in the United States of America. Many other important structures such as: nuclear reactor containments, nuclear waste storages, large oil or natural gas reservoirs, large chemical containers, ammunition storages and military installations, could be threatened in the future by similar attacks or by accidents or in case of war.
Many of such hardened and rigid structures have reinforced concrete outside walls that may—in some buildings—exceed 2.0 meters in thickness. However, the thickness is usually less when the wall is made of pre-stressed concrete. It is also common to have the structure lined with a layer of steel or a non-metallic material. Moreover, reinforced concrete structures which are partially or completely buried under compacted layers of soil are common, especially, in military installations. Furthermore, it is also a common concept of design to have a cluster of buildings where the building which is required to be the most protected is surrounded by the others.
The common character of most of the above mentioned concepts is the very high rigidity of the outside walls of the structure, which represents a strong shield that is hard to penetrate by hard or soft missiles. However, the challenges represented by a crash of a large civilian air craft or a smart missile which could penetrate thick walls of reinforced concrete, require innovative designs that offer more protection for such important structures and to increase their capabilities to withstand very high impactive and impulsive loads.
SUMMARY OF THE INVENTION
[0003] This present invention is based on a novel approach that allows some types of structures to absorb very high energy, which could be generated by soft or hard missiles or by other types of impactive and impulsive loads. In this invention, the main structure is protected by a movable outer shield where the main structure and the movable outer shield are spaced apart and the space between them is filled with a selected crushable filling material. Moreover, the outer shield is initially fixed by an anchorage system; however, if the load exceeds certain limit, the anchorage system collapses and the outer shield becomes unconstrained and—under the effect of the load—undergoes free body motion crushing the filling material and absorbing very high energy.
The following remarks should be considered in regard of this structural system:
1. If the load is less than a certain value, then the outer shield should undergo limited small displacements, causing some strains in the filling layer. This represents the first level of load resistance, which should be sufficient to withstand impactive and impulsive loads and some other types of loads as well; such as tornados and earthquakes up to a certain value. 2. If the load exceeds that value, then the anchorage system should collapse allowing the outer shield to have a rigid body motion by sliding against the sliding-plane and crushing the filling layer, which should absorb a substantial amount of energy. This represents the second level of load resistance. As the shield reaches the maximum possible displacement, a missile—if one is the source of the load—should face three barriers represented by the outer shield, the crushed and compacted filling layer, and finally the wall of the main structure. These three elements can resist an additional and substantial impact force, while the missile's kinetic energy would have been substantially reduced. The collective resistance of these elements represents the third level of load resistance. 3. The possibility of perforating the main structure of this structural system or causing a loss of air tightness to it by a hard missile is considerably lower than it is for other systems due to several reasons:
A. Allowing the outer shield to undergo large displacements substantially reduces the extremely high force generated by the impact of two rigid bodies. B. Creating discontinuities in the impacted structure by having three different layers, which prevents the propagation of stress waves. C. Reducing the possibilities of spalling and scabbing of concrete at the impacted area of the main structure. These phenomena should occur in reinforced concrete walls—even the very thick ones—when impacted by a hard missile. D. Absorbing a substantial amount of the kinetic energy of the hard missile by perforating the outer shield and crushing the filling material before the missile could hit the main structure.
4. In this structural system, the impact force could be resisted by having the anchors and the filling material on the side of the impact subjected to compressive stresses and by having the anchors and the filling material on the opposite side of the impact subjected to tensile stresses. This is an advantage over ordinary structural systems where the load is applied only on the impacted side. 5. Part of the energy of the load is dissipated in the friction generated during the sliding motion of the outer shield under its own weight and any vertical downward force component of the load. 6. The elevation of the sliding-plane should be determined based on the circumstances of each structure including the level of protection provided by the surrounding buildings, the location of the structure, its size, the limit of the outer shield weight. It is possible to have the sliding-plane little above the foundation level of the main structure or at the base level in case of—for instance—an elevated tank. Moreover, it could be possible in some structures to have more than one sliding-plane in the outer shield. 7. Having the crushable layer made of a fire resisting material and adding thin layers made of another fire-resisting material between the crushable layer and the main structure should provide effective fire protection to the structure. This protection is particularly important if the load is due to a crash or explosion which is—in most cases—followed by a fire. 8. This structural system could be used in constructing new structures or in fortifying existing structures as well. In the latter case, the existing structure should be considered as the main structure of the system. The system could also be used for structures with different shapes and sizes. 9. This structural system provides protection to its main structure from extreme weather conditions and large cyclic seasonal temperature variation. This protection maybe necessary in case of an existing structure that has considerable cracking. Moreover, this system could be used to substitute an existing structure for the partial loss of pre-stressing if it is an aging pre-stressed concrete structure. 10. It is possible to design the crushable layer so that it could be used during construction as formwork for a reinforced concrete outer shield which could significantly reduce the construction cost. Moreover, the outer shield could be made of reinforced concrete, steel or any other suitable material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows the structural system, where 1 is the main structure, 2 is the crushable layer, 3 a is the movable part of the outer shield, and 4 - 4 is the sliding-plane.
[0019] FIG. 2 is a cross-sectional view taken along line I-I of FIG. 1 assuming that the main structure is cylindrical in shape.
[0020] FIG. 3 is a cross-sectional view taken along line I-I of FIG. 1 assuming that the main structure is cylindrical in shape and is provided with four counterforts.
[0021] FIG. 4 is a cross-sectional view taken along line I-I of FIG. 1 assuming that the main structure is cubic in shape.
[0022] FIG. 5 is an enlarged view of circle II of FIG. 2 .
[0023] FIG. 6 is a partial cross-sectional view along the vertical axis of the main structure, showing the main components of the system, the sliding-plane; 3 b, the fixed part of the outer shield and; 5 , a construction joint between the main structure and the fixed part of the outer shield.
[0024] FIG. 7 is an enlarged view of circle III of FIG. 6 . It shows the details at the sliding-plane, where 6 is a fixed plate; 7 , a sliding plate; 8 , anchor bolts for mounting the fixed and sliding plates to the fixed and movable parts of the outer shields, respectively; 9 , a sealant to seal the gap between the fixed and movable parts of the outer shield from outside; 10 , an anchor rod connecting the outer shield and the main structure; 11 , a base plate for the anchor rod; 12 , an anchor bolt fixing the base plate to the main structure; 13 , a hole drilled through the outer shield; 14 , an adhesive material filling the space between the anchor rod and the walls of the hole; and 15 , a sealant to plug the hole of the outer shield from outside.
[0025] FIG. 8 is a partial cross-sectional view along the sliding-plane 4 - 4 of FIG. 1 in the direction of the arrows, where 16 is a key, which is a projection of the movable part of the outer shield; 17 , two sides of a keyway which is a slot created into the fixed part of the outer shield in which the key is embedded and; 18 , a crushable material filling the space between the key and the two sides of the keyway.
[0026] FIG. 9 is a cross-sectional view along line I-I of FIG. 1 showing the displaced outer shield due to an impactive or impulsive load.
[0027] FIG. 10 , shows the assumed location of a coordinate system used to explain the concept of this invention.
DESCRIPTION OF THE INVENTION
[0028] The current invention is related to a structural system that could withstand severe loading conditions, especially, high impactive and impulsive loads which may result from blast pressure, tornado-generated missiles, aircraft strike, and other sources. This system provides protection to the main structure 1 , by having a movable outer shield 3 a spaced apart from the main structure and a crushable filling layer 2 is filling the space in between. The high energy absorption capacity of this system is due in part to the ability of the outer shield to slide against a sliding-plane 4 - 4 crushing the filling layer. The outer shield has a fixed part 3 b, which should be separated by a structural joint 5 from the main structure. This fixed part carries a fixed plate 6 , which defines the sliding-plane. The movable part of the outer shield has a plate 7 , which is provided with sliding means in order to allow the movable part of the outer shield to slide against the fixed plate. Both of the two plates are anchored to the outer shield by anchors 8 . A sealant 9 is used to seal the outside gap between the two plates. The anchorage system could be designed in many different ways; one of them for example is to have rigid anchor rods 10 embedded at one end into holes 13 drilled through the outer shield, where the space between each bar and the walls of the hole in which it is embedded is filled with an adhesive material 14 . The other end of each anchor rod is connected to a base plate 11 and the plate is mounted to the main structure by anchors 12 . The holes are drilled through the outer shield at some selected locations and sealed from outside by a sealant 15 in order to protect the connections from humidity and other weather effects. Moreover, in order to resist the twisting movement which should result from an eccentric load, keys 16 and keyways 17 are created between the movable and the fixed parts of the outer shield with a relatively large clearance between the key and the sides of the keyway filled with a crushable material 18 . A second way to make the connections of the anchorage system is to fix the movable part of the outer shield 3 a to the fixed part 3 b using vertical dowels, which should be sheared off at the impact. Assuming that the main structure is cylindrical in shape, and is located in a Cartesian space so that the Z axis coincides with the vertical axis of the structure as shown in FIG. 10 , then a general impactive or impulsive load can be considered as the equivalent of the following six components: X, Y, Z, M x , M y and M z , where X, Y and Z are the force components in the directions of the X, Y, and Z axes, respectively and M x , M y and M z are the moments about the X, Y, and Z axes, respectively. The Most damaging component to the structure is the force component that is in the radial direction normal to the vertical wall. This force is the resultant force of the X and Y components. In the current invention, this force is resisted as follows depending on its magnitude and area of application:
1. At a relatively small load, the outer shield should undergo a limited displacement crushing the filling layer locally at the area of the impact. Some of the connections of the anchorage system may fail as well. 2. At a higher level of loading, all the connections of the anchorage system should fail and the outer shield should undergo a free body motion sliding against the sliding-plane and crushing the filling material until the total energy of the load is absorbed or until the outer shield reaches the maximum possible displacement. 3. At the highest loading condition, the displaced outer shield, the compressed filling layer and the main structure should act as a structural system subjected to the effect of the remaining unabsorbed energy.
[0032] The vertical force component Z is resisted by the own weight of the shield if it is an uplifting force or by the reaction of the fixed plate if it is acting downward. The twisting moment M z is created mainly by the tangential friction and is resisted by the key-keyway interaction. Other moment components: M x and M y should have an overturning action, however, they are counteracted by the stabilizing moment which is due to the own weight of the shield. Moreover, the possibilities of overturning the shield by an impactive or an impulsive load are very remote since that requires the disintegration of the shield or the main structure itself.
[0033] There are two types of missiles: soft missiles and hard missiles. The type of missile is determined according to its relative rigidity comparing to the impacted structure. The effect of any of the two types of missiles upon a structure can be studied by analyzing the effect of the associated load-time function on the global stability of the structure. However, in case of a rigid missile, it is necessary to assess the possibilities of perforating the structure by the missile as well. As a hard missile hits a rigid structure, a very high impact force is generated for a very short period of time causing local damage to the structure at the location of the impact. This local damage, while does not undermine the integrity of the structure, however, it could result in serious consequences, in case—for example—a reservoir that contains flammable material or a nuclear reactor containment that is required to be airtight.
[0000] This structural system—with its hardened rigid outer shield—offers protection against both types of missiles. The protection against the effect of the load on the global stability of the structure was discussed earlier in this description, while the protection against the perforation risk was discussed in the invention summary.
It should be noticed that the relative strength of the different elements of this structural system should be observed in order to have the required performance under severe loading conditions. For instance, the anchorage system should be designed so that it collapses first before the outer shield is perforated by a representative missile. However, since there is a wide variety of loading conditions, then the design of this structural system should be optimized depending on the circumstances of each application. One of the materials which could be utilized in making the filling crushable layer is the Stabilized Aluminum Foam (SAF), which has the following properties:
1. High energy absorption capacity. 2. Low heat conductivity. 3. Fire Resistance. 4. High soundproofing. 5. High damping capacity. 6. Environmentally safe.
[0040] The following is an explanatory example of designing a system that is capable of withstanding very high impactive load utilizing the Stabilized Aluminum Foam: An elevated 18 m high cylindrical reservoir has an outside diameter of 40 m and contains highly flammable material. Due to the construction of a nearby airport, it was found that the reservoir is vulnerable to aircraft strikes. It is required to protect the reservoir so that it becomes capable of withstanding a normal impact of an aircraft landing at a speed of 300 km/h. The weight of the aircraft is assumed to be 250 tons and the estimated impact force is 244 MN.
[0000] Assuming that the structural system comprises of the following:
1. an outer shield made of reinforced concrete where both of its top cover and side walls are 2′ thick and its total weight is 56 MN, 2. a crushable filling layer made of 18″ thick Stabilized Aluminum Foam, 3. an anchorage system that consists of 48 dowels, each fail in shear if subjected to a shear force of 0.41 MN. Then: 1. The kinetic energy of the aircraft=868 MJ 2. Volume of SAF covering the impacted side=29.1×18=523.8 m 3 3. Volume of the uncrushed SAF following a crash=10.4×18=187.2 m 3 4. Volume of crushed SAF=523.8−187.2=336.6 m 3 5. Energy absorbed in crushing the SAF=0.8 MJ/m 3 ×336.6 m 3 =269 MJ 6. Energy absorbed in moving the outer shield=56 MN×0.8×0.46 m=20.5 MJ 7. Estimated energy absorbed in collapsing the anchorage system, keys, plastic deformations of the outer shield and friction=38.5 MJ 8. Estimated energy absorbed in crushing the aircraft=540 MJ 9. Total energy absorbed=868 MJ
It should be noticed that the force generated by the impact is enough to crush the SAF and to slide the outer shield:
Impact force=244 MN
Force required to crush foam=40×18×0.30=216 MN
Force required to slide the outer ring=56 MN×0.15=8.4 MN
Force required to collapse the anchorage system=48×0.41 MN=19.6 MN
Total force required=216+8.4+19.6=244 MN
In this example, the first level of load resistance is defined by the capacity of the anchorage system which is 19.6 MN; the second level of load resistance is the range of loads between 19.6 and 244 MN, where the latter is the required load to displace the outer shield to the position of maximum displacement. The third level of load resistance is defined by loads higher than 244 MN.
In the previous example, the landing weight, the landing speed and the impact force of the aircraft are representative values for a jumbo jet. It was shown that the total kinetic energy of the aircraft could be absorbed in displacing the outer shield alone, which indicates that this structural system is capable of protecting the main structure against even higher impactive or impulsive loads.
Moreover, it should be noticed that following the impact, the displaced outer shield should exert additional moments on the main structure due to the eccentricity of the structure's own-weight in this case. This moment should increase the stresses at some locations; however, these additional stresses should not be significant due to the small ratio between the maximum displacement and the radius of the structure, which is in this example=0.36/20.0=0.018.
Furthermore, if the force required to displace the outer shield is very high due to the large surface area of the main structure, and consequently, the large surface area of the crushable layer, then it is possible to decrease this force by creating recesses in the crushable layer. The thickness of the foam at the recessed areas should be equal to the thickness of the main layer at the densification strain. For instance, the thickness of the crushable layer in the previous example is 0.46 m and the thickness of this layer at the densification strain is 0.09 m, then it is possible to decrease the thickness of the crushable layer to 0.09 m at several areas. This should result in decreasing the force required to displace the shield without undermining the function of the crushable layer.
[0053] While particular embodiments of the invention have been disclosed, it is evident that many alternatives and modifications will be apparent to those skilled in the art in light of the forgoing description. Accordingly, it is intended to cover all such alternatives and modifications as fall within the spirit and broad scope of the appended claims.
|
A structural system that is capable of absorbing high impactive and impulsive loads comprises of the following elements:
(a) Main Structure: should be one of certain types of structures such as: containments, reservoirs, tanks, storages, etc. (b) Crushable Filling Layer: a layer made of crushable, thermally isolating and fire resisting material surrounding the outer walls of the main structure and filling a space between the main structure and an outer shield. (c) Outer Shield: an outside hardened structure fixed by an anchorage system and resting on a sliding-plane. (d) Anchorage System: a set of anchors that hold the outer shield in place and collapses if the impactive or impulsive load exceeds certain level allowing the outer shield to slide crushing the filling layer and absorbing substantial amount of energy.
| 4
|
This invention relates to starter motors for internal combustion engines and has particular reference to starter motors which operate mechanically using stored strain energy as the power source.
BACKGROUND OF THE INVENTION
Modern starter devices are driven by electric motors which must be powerful enough to crank an engine. The energy source is usually a battery which will typically need to provide a current in excess of 200 amps at 12 volts to provide starting of an engine. In particular the starting of heavy diesel engines can require a power supply in excess of this.
In extreme conditions such as severe heat or cold or humidity, the battery and its associated electrical system can quickly become impaired. This is particularly true where servicing and maintenance are sub-standard or absent. Furthermore, in certain environments, electrically powered starters represent a fire hazard and, for example, the use of such starters in mines, is not permissible.
Mechanical starters provide a more reliable source of starting energy for internal combustion engines than electrically powered starting devices.
Mechanical starting devices hitherto employed typically comprise spring means for storing energy, means for applying energy to said spring means to store energy therein and drive means for converting said stored energy when released to provide a starting impulse for said engine.
In devices of the kind described, the spring means may comprise a bank of disc springs; the springs are strained by repeated manual rotation of a crank handle which rotates a worm on a shaft passing through the centre of said springs which worm is threaded through an end plate so that rotations of the worm moves the end plate to compress the discs. Once sufficient energy has been stored, the energy is manually released by disengaging a ratchet pawl. The spring reacts in an axial direction and the mechanism converts that axial movement into rotational energy. The rotational energy is directed to an output shaft which may include a pinion adapted to mesh with a ring gear carried on an engine flywheel.
Such known mechanical starters use a detachable crank handle to "wind up" the spring mechanism in order to store energy therein. These handles need to be of considerable dimension in order to apply the necessary energy and to provide the necessary mechanical advantage for the operative. This in turn limits the positioning and orientation of the starter to a position which allows free access of the crank handle and easy access generally to that part of the engine.
Compression ignition engines such as diesel engines are particularly amenable to starting by such mechanical devices because they do not require in the normal course of events the associated electrical system to maintain them in operation. Furthermore, the amount of rotation available to a mechanical starter is limited by the travel of the disc springs in the time period before the stored energy is exhausted. In starters currently available, the spring travel is small and short lived. They are, thus, most successful for use with multiple cylinder diesel engines where a combustion event is likely to occur over the arc of rotation of the crank shaft induced by the starting device.
As stated above the spring energy of the disc springs is released as an axial motion which has to be converted to rotational motion to be useful in the starting of an engine. The energy losses involved in the conversion processes are significant and furthermore such a motor must be heavily engineered to be able to withstand extremely high axial forces exerted by the springs. This adds to both cost and weight, to such an extent, as to make their use at a premium.
There is, therefore, a need for a mechanical starting device of improved efficiency and versatility which enables the starter to be used to start a wide range of engines. There is also a need for a mechanical starting device having reduced weight and being of cheaper construction. There is a further requirement for a starting device which is convenient to operate and does not require, of necessity, a crank handle of large throw.
U.S. Pat. No. 3,127,883 seeks to provide a solution to this problem and the primary aim of the invention described therein is to provide an improved spring starter motor that is efficient and safe. More specifically, it is an object of the invention to provide an improved starter motor which cannot be accidentally tripped when wound and which has no projecting parts which are driven during the starting operation.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a mechanical starting device comprising a spiral power spring for storing energy, winding means for applying energy to said spring to store energy therein and drive means for converting said stored energy when released to provide a starting impulse for an engine, characterized in that said spring and the winding means act in conjunction with control means (94,95,100,107) adapted to release the stored energy of the spring to a drive shaft automatically after a given amount of energy has been stored in the spring.
The present invention further provides in the further aspects a mechanical starting device which is characterised by one or more of the following features taken separately or in any combination:
(i) The spring means comprises a spiral power spring; as used in this specification the term "spiral power spring" will mean a clock type spring comprised of a material forming a continuous spiral of flat ribbon material in which potential is stored by tightening the spiral coils of the spring.
(ii) The spring means may comprise a bank of ribbon springs operating in parallel or a single spring.
(iii) The spiral ribbon spring may be altered in its dimension both width, length and thickness in order to control the output power and number of turns of the starting device.
(iv) The spiral spring means can be strained by rotation of one end relative to the other, the rotation being in the same direction as the spring spiral.
(v) One extremity of the spring spiral may be secured to an output shaft while the other end is rotated to tighten the spiral and means may be provided to release the output shaft whereby the potential energy stored in the spring is released directly to rotational energy.
(vi) The storage of potential energy may be achieved by rotation of the inner edge while the outer extremity of the spring is held.
(vii) The storage of potential energy may be achieved by rotating the outer edge relative to the inner extremity, thus resulting in a mechanical advantage which eases the winding process.
(viii) The spiral power spring may be in the form of a coil which is connected at its inner edge to the drive shaft and at its outer extremity to a rotating housing. The rotating housing is preferably coaxial with said drive shaft and adapted to be rotatable relative thereto.
(ix) Winding means may be provided which is adapted to rotate the spring housing member relative to the inside edge of the spring to store potential energy therein.
(x) The winding means may be a rope pull winder.
(xi) Gear means may be provided between the winding means and the rotating spring housing for the purpose of providing a mechanical advantage therebetween. The gear means may be an epicyclic gear means.
(xii) The spiral power spring and the winding means therefore, may act in conjunction with a control and release means which includes means to release the potential energy of the spring to the drive shaft automatically after a given amount of energy has been stored in the spring.
(xiii) The control and release means may include a latch to prevent rotation of the drive shaft during winding and release means may be provided to unlatch the drive shaft once winding is complete.
(xiv) An epicyclic gear train may be provided between the winding means and the spring means and may comprise at least three planet gears which are substantially uniformally circumferentially spaced about the axis of the drive shaft thereby providing a solid structure to balance the stresses during winding.
(xv) The winding means may include a substantially disc-shaped winding member adapted to be wound by means of a pull rope. The winding means may include a recoil spring and a ratchet whereby on pulling the winding rope the ratchet is engaged to drive the gear train and effect winding of the spring and on release of the tension in the winding rope the recoil spring serves to rewind the rope ready for the next pull. The use of a pull winder in these circumstances permits much more flexible use and operation. For example, the starting device in accordance with the present invention may be incorporated in a much more restrictive space and the starting rope may be led to a more convenient position for operation. In one aspect of this feature of the invention, the rope may be fed through a tube or conduit to a much more convenient position on a dash board or instrument panel significantly away from the starter device per se as attached in its operative position on the engine. A further advantage is that there is less potential danger to using a rope pull of the kind described compared with a crank handle. A failure in the crank handle mechanism may result in unexpected crank on rotation with corresponding arm injury to an operative.
(xvi) The winding means may further include ratchet means to provide for integer increases in the potential energy of the spring during winding. In particular aspect of the invention the ratchet for the recoil device and the ratchet for the spring housing may be substantially concentric and provided in a single annulus.
(xvii) The control and release means may comprise a further pawl and ratchet active between the drive shaft and a housing for the device.
(xviii) The pawl may be arranged to coact with a cam surface, which is caused to rotate in response to the winding operation, the arrangement being such that rotation of the cam brings the extremity of the cam edge into tripping relationship with the pawl only when sufficient potential energy has been applied to the spiral power spring.
(xix) The cam may be driven by the spring housing via an epicyclic gear arrangement.
(xx) The ratchet wheel of the release and control means may be provided with contoured ratchet recesses in the outer surface thereof and each recess is adapted to cooperate with a corresponding contoured nose at the end of the pawl, the arrangement being such that the minimum of friction is required to disengage the pawl from the corresponding recess in the ratchet thereby to release the drive shaft.
(xxi) The pawl may be located on a fixed part of the housing and the ratchet may be associated with the drive shaft. In a particular embodiment of the present invention, the ratchet may form part of the drive pinion which engages the starter ring of the engine to be started.
(xxii) The starter pinion and its associated ratchet may be provided with a central bore with multi-start threads or teeth cut internally thereof.
(xxiii) The pinion may be adapted to be mounted on corresponding multi-part teeth carried at a forward end of the shaft adapted to be deposed towards the flywheel of the engine to be started. The pinion may be biased to a position out of engagement with the said starter ring as, for example, by use of a compression spring, the arrangement being such that in order to bring the pinion into engagement with the starter ring, relative rotation of the pinion relative to the drive shaft will cause the pinion to advance along the multi-start threads or teeth to enter into engagement with the starter ring per se.
(xxiv) The pawl may be elongate in the direction of travel of the pinion to remain in engagement with its corresponding recess on the ratchet. The assembly should be such that on commencement of winding, the pinion will be prevented from rotation by means of the pawl, but the shaft will be free to rotate and the interaction of the multi-start teeth or threads will serve to drive the pinion into engagement with the starter ring. At the extremity of its travel, further rotation of the drive shaft will be prevented.
(xxv) In a particular aspect of the invention the essential components other than the spring are manufactured of plastics materials.
(xxvi) The epicyclic gear trains are generally formed from glass filled nylon while the drive shaft, drive pinion and winding gear may be produced of a nylon derivative commercially available under the trade name "VERTON". The use of such material has the advantage that the device is light in weight, requires no bearings between the moving parts and is cheap to manufacture. An additional advantage is that the extensive use of the plastics components throughout the device means that the device is very well adapted to working in inclement conditions such as highly humid conditions or a marine environment.
Following is a description by way of example only with reference to the accompanying drawings of methods of carrying the invention into effect.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal section of a starting device in accordance with the present invention.
FIG. 2 is an identical view to FIG. 1 showing the starter pinion in the engaged position.
FIG. 3 is an end view of an end cap of the device of FIG. 1.
FIG. 4 is a side view of FIG. 3.
FIG. 5 is a side view of the spring housing or carcase of the device of FIG. 1.
FIG. 6 is a section on the line A--A of FIG. 5.
FIG. 7 is a detail of the drive shaft of the device of FIG. 1.
FIG. 8 is a section of the winding ratchet of the device of FIG. 1.
FIG. 9 is an end view of FIG. 8.
FIG. 10 is a section through the spring drum of FIG. 1.
FIG. 11 is a detail of the pawl cam of the device of FIG. 1.
FIGS. 12, 12A, 12B and 12C are details of the pawl.
DETAILED DESCRIPTION OF THE INVENTION
A starter device in accordance with the present invention comprises an outer housing 10 of generally cylindrical configuration. The housing 10 has at its rearward end an end cap 11 which has an inwardly directed central spigot 12. End cap 11 is provided with a plurality of forwardly extending tongues 13 (see FIG. 4) adapted to engage with corresponding portions at the rearward end of cylindrical housing 10 for the purpose of securing the end cap thereto. The end wall 14 of end cap 11 is generally circular and is provided with an inwardly directed annular rib 15. The external cylindrical wall 16 of end cap 11 is provided with an opening 17 which is provided with a pair of axially extending rounded lips 18 which together define a rope guide opening 19. Cylindrical housing 10 is provided at its forward end with an inwardly directed annular wall 20 provided with an intermediate step portion 21 which carries at its inner end a forward extension 22. Forward extension 22 terminates in an inwardly directed flange 23 which carries a plurality of circumferentially spaced, forwardly extending engaging elements 24, each having at its forward extremity an inwardly directed barb 25. The intermediate step portion 21 carries on its internal surface a plurality of teeth constituting a ring gear 26. The forward extension 22 is Defined by a pair of spaced parallel walls and a pair of generally arcuate walls 28 and 29, (see FIG. 6) the lower wall 29 has an inwardly projecting arcuate hook 30 extending generally longitudinally of the forward extension and serving to define a generally cylindrical recess 31' which is open longitudinally along its length to receive a pawl element as hereinafter described.
The forward extension 22 of the cylindrical housing 20 of cylindrical housing 10 is adapted to carry a pinion housing 35 comprising a generally cylindrical portion 36 adapted to overlay and be a sliding fit on forward extension 22 of cylindrical housing 10, said portion 36 having a forward annular wall 37 extending generally inwardly therefrom and being provided with a plurality of openings 38 the inner wall of each of which has a step or detent 39, the arrangement being such that when the pinion housing 35 is entered over the cylindrical portion 22 of housing 10, the barb portion 25 of each engaging element 24 latches into detent 39 to retain pinion housing 35 in place. The forward wall 37 is provided with a pinion casing 40 which is cut away at its lower end and terminates at its forward extremity in a journal 41. The casing 40 is reinforced by circumferentially spaced flanges 42 (see FIG. 2).
The journal 41 carries a stub axle 43 extending rearwardly of the journal, said stub axle terminating in a barbed rib 44. A drive shaft indicated generally at 45 is provided with a generally hollow central bore 46 which bore is expanded to define an annular shoulder 47 which is adapted to engage with barbed rib 44 of stub axle 43 for retaining the drive shaft on said axle; said shaft being arranged for rotation relative thereto.
The drive shaft 45 is provided towards its forward end with a plurality of spiral splines or teeth and immediately rearwardly thereof is provided with a further reduced cylindrical portion 48, 49 constituting a bearing surface.
The rearward part of the shaft is provided in its external surface with a plurality of longitudinal grooves or splines each approximately 0.5 mm deep extending towards the rearward end 51, which latter is slightly reduced in diameter and is provided with a smooth cylindrical surface constituting a bearing surface.
The central bore 46 of drive shaft 45 is adapted to accommodate at its rearward end a winding ratchet 52 (see FIG. 8) comprises a generally tubular portion 53 adapted to enter into the central bore 46 of drive shaft 45, and an annular plate 54 terminating in a rearwardly directed circumferential flange 55. The rearward face of annular plate 54 carries towards the circumference thereof 6 circumferentially spaced ratchet holders 56 and 57, alternate ones of which are handed as shown in FIG. 9. Ratchet holder 56 is a "outer" ratchet holder and ratchet holder 57 is a "inner holder". Each ratchet holder comprises an arm 58 with a long element 59 and a short element 60. The point of bifurcation of arm 58 to long element 59 and short element 60 defines a part cylindrical socket which latter is adapted to receive a corresponding part of a "dog bone" ratchet element (not shown).
The dog bone ratchet elements are also handed and extend between adjacent holders. The outer ratchet holder 56 contains a dog bone ratchet element 62 having a pawl portion 63 and an arcuately extending arm 64, the arrangement being such that the pawl portion 63 extends outwardly away from the centre of the annular plate 54.
Inner ratchet holder 57 holds inner dog bone ratchet element 62' having a pawl element 63' and arcuate arm 64', the arrangement being such in this case that the pawl element is directed inwardly towards the axis of plate 54. The complete assembly of dog bone ratchet elements 62, 62' in each of the holders 57 and 58 respectively serve to define an annular ratchet assembly operative both inwardly and outwardly of the assembly.
The rearward end of tubular portion 53 carries for relative rotation thereto a rope element 69. This comprises a generally circular winder drum body 70 carrying on its forward face a ratchet which is adapted to engage with the inner pawl 63' with corresponding dog bone ratchet elements 62' carried by holders 57 on annular plate 54. Element 69 has a forwardly extending spigot 72 adapted to enter tubular portion 53 of winding ratchet 52. The axis of body 70 is provided with a blind bore 73 adapted to receive spigot 12, which latter provides the rearward support for the drive shaft, winding ratchet and winding drum assembly. The drum is provided with a peripheral rope receiving groove 74 whereby the end of the rope can be entered and secured with a cavity 75, which is then wound within groove 74 and exits from the drum by means of rope guide opening 19 in end cap 11. A recoiled spring 76 is provided between end cap 11 and winder drum 69 to effect rewinding of the rope on each stroke of the pull.
Shaft 45 carries, journalled for rotation with respect thereto, a spring housing indicated generally at 80. The spring housing has a generally cylindrical outer wall 81, a front end face 82 terminating at its inner extremity in a forwardly extending sleeve 83 carrying on its outer cylindrical surface, a plurality of gear teeth 84 which forms a 36 toothed, 24 dp spur gear. The rearward end face 85 is provided with a central bore adapted to be accommodated about drive shaft 45 and is provided, intermediate the inner and outer extremities of rearward face 85, with three hub 85' spaced circumferentially about the axis of the housing. Each hub 85' is adapted to carry an 18 tooth 12 dp spur gear freely rotatable thereon, each of said gears engaging with the sun gear 65 carried by the winding ratchet. Each of spur gears 87 also engages with an annular ring gear 88 secured to the end cap 14 and housing 10. Ring gear 88 is provided in a rearward part with a ratchet extension 89 which is provided on its cylindrical inner surface with a plurality of ratchet steps adapted to engage with the outer dog bone ratchet pawls 62 to allow rotation of the spring drum 80 relative to housing 10 in one direction only.
The drum 80 carries a single, spirally wound, leaf power spring generally in the form of a clock spring, the inner end of which is fixedly secured to drive shaft 45 and the outer extremity of which is secured to casing 80. The inner end of the spring is secured to the shaft as by gluing whereby the splines on the shaft form an interengagement between the steel of the spring and the shaft. The drum housing 80 is formed of a plastics material which is roughened on the inside and a substantial area is glued to the adjacent surface of the spring, the arrangement is such that with the shaft 45 locked against rotation, pulling on the rope end causes winder drum 69 to rotate to cause interaction between the inner ratchets to drive winding ratchet about its axis relative to the shaft while the outer ratchets ride over the outer pawls. The rotation of the winding ratchet 52 produces rotation of spring drum 80 via the sun gear 65, spur gears 87 and ring gear 88 at a much reduced rate to the rate of rotation of winder drum 69. When the rope has been withdrawn to the maximum of its travel, recoil spring 76 will have been tensioned so that relaxation of the rope will allow recoil ring 76 to reverse the direction of rotation of the winder drum relative to the winding ratchet 52 which winding ratchet 52 is locked against reverse rotation by means of the interaction between pawls 63 and the ratchet steps on ratchet extension 89 thus allowing the additional tension applied in the main spring 90 to be stored as potential energy. Continued pulling on the rope of the winder drum and subsequent relaxation will produce incremental increases in the potential energy stored in the spring 90 until the ring reaches the optimum level of tension.
The shaft 45 carries forwardly of the front face 82 of the spring drum 80, a cam member 93 journalled for rotation about shaft 45. Cam member 93 comprises a substantially planar disc with a forwardly extending cam element 94. The rearward face of cam member 93 is provided with three equally spaced gear carrying studs 95 each of which carries a planet gear 96, the teeth of which are adapted to mesh between the gear teeth 84 on cylindrical extension 83 of spring drum 80 and the ring gear 26 provided internally of housing 10, the arrangement being such that rotation of drum 80 serves to drive cam 94 about shaft 45. Cam 94 is configured as shown generally in FIG. 11, the cam surface being generally eccentric and being substantially arcuate over approximately half of its surface then extending into a cam arm 98. Cam pawl 100 (see FIG. 12) is generally longitudinal and is provided with a pivot portion 101 extending longitudinally of the cam and adapted to be accommodated within the hook 30 (see FIG. 6). The pawl nose is generally rounded in accordance with the sections 12a, 12b and 12c of FIG. 12 at various intermediate stages along the longitudinal length of the pawl.
Forwardly of the cam member, shaft 45 carries pinion 104 comprising of forward tooth part 105 adapted to engage with the teeth of the starter ring of an engine to be started and intermediate portion 106 and rearward ratchet 107 which is adapted to engage with pawl 100. Pinion 104 is spring loaded rearwardly with respect to pinion housing 35 by means of compression spring 108. Intermediate portion 106 is provided on its interior surface 109 with a plurality of spiral splines or teeth 110 adapted to engage with spiral splines or teeth 48 on the drive shaft, the arrangement being such that relative rotation between the shaft 45 and pinion 104 will result in the pinion moving axially of shaft 45 either forwardly or rearwardly to the limit of its travel.
As the pinion moves axially of the drive shaft it slides along the pawl 100, the different contours of which engage with the ratchet 107 on the pinion. The nose end configuration of the pawl 100 is arranged so that the nose of the pawl is "self-caming" with the corresponding recess in the ratchet and the arrangement is such that with the pinion fully forward as shown in FIG. 2 only slight force is required to disengage the pawl from the pinion.
In operation, pulling on the winding rope will result in rotation of the winder drum 69 with corresponding rotation of the complete drive assembly including drive shaft 45. The pinion is lightly held against rotation by the action of spring 108 and is thus caused to advance to a position in which the teeth 105 engage with corresponding teeth on the starter ring of the engine to be started. When the pinion has advanced to the extremity of its travels, the profile of the pawl shown in section 12c will be engaged with a recess in ratchet 107 thereby locking the pinion against rotation with respect to the pinion housing and the casing 10 attached thereto. At the same time because the pinion is at the forward extremity of its travel, shaft 45 will also be locked against rotation. Pulling on the rope will result in winding of the spring 90 in the manner described above and will produce rotation of the cam. Continued strokes of the winding rope will produce progress tightening of the spring 90 until the cam 94 has rotated until cam lobe 97 engages under pawl 100 to lift the body of pawl 100 out of engagement with the corresponding recess in ratchet 107 of pinion 104.
Free from its constraint, the shaft 45 and pinion 104 carried thereby is free to rotate under the influence of the spring which then imparts direct rotational movement to the shaft which drives the pinion which in turn drives the ring gear on the flywheel of the engine to be started. When the engine fires, the backlash of the ring gear reduces and removes the frictional loading on the pinion 105 and the compression spring 108 drives the pinion out of engagement of the ring gear to the start position. The cam 94 will now have rotated so that the lobe 97 will have passed the point of contact with the pawl 100, the pawl 100 will now be engaged with the ratchet 107 and the body of the pawl will be in contact with the arm 98 which being flexible will serve to urge the cam out of engagement with the recess until winding has commenced to such an extent that the pinion has once again moved forward along the shaft 45 to engage the ring gear, by which time the cam lobe 94 will have advanced sufficiently that the arm will be out of engagement with the pawl and the pawl will be once more engage with a recess in ratchet 107.
With the exception of the spring, the components of this starter device can all be made of structural plastics materials. The result is that the resultant starter device is light in weight, requires no bearings and apart from the spring, is substantially corrosion proof.
The cam release arrangement of the device described above provides protection against over-winding of the spring. If the spring is over-wound then the smooth energy delivery profile of the spring is not achieved and in many cases the spring "collapses" to prevent the delivery of significant or sufficient amounts of energy. The cam release device of the present invention overcomes this problem. The performance output of the spring can be varied by changing the gear ratios between the various components of the epicyclic gear trains and the energy delivery device of the spring itself can be adjusted by a combination of length, spring thickness and spring width.
Starter devices in accordance with the present invention and generally as described above are suitable for starting all forms of ignition combustion engines.
|
Starter motor for internal combustion engines which operates mechanically using stored spring energy as the power source whereby the spring comprises a spiral power spring.
| 5
|
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
BACKGROUND OF THE INVENTION
The present invention relates generally to downhole circulation subs. More particularly, this invention relates to the use of an electric motor to drive a downhole circulation sub.
Retrieval of oil and other hydrocarbons form below ground typically includes drilling a borehole, also known as a wellbore, in the Earth. As drilling technology has advanced, these boreholes may be drilled off of vertical, sometimes even sideways or horizontal. In this way, an operator can reach a formation that contains the desired substance. Thus, the terms “upper” and “lower”, or “above” and “below” as used herein are made with respect to a position in the borehole, and may not necessarily reflect whether two elements are above or below each other in an absolute sense. FIG. 1 includes rock formation 100 surrounding a borehole 110 . Borehole 100 is formed by the cutting action of drill bit 125 attached to rotating drill string 120 . Drill string 120 also includes a circulating sub 170 .
A variety of drill bits 125 are known, but a common feature is that each contains ports or nozzles on its face to direct drilling mud 130 (also known as drilling fluid) flowing through drill string 120 . The drilling mud 130 exits the drill bit as shown by arrows 160 . This mud not only cools the face of the drill bit, but also carries to the surface a substantial amount of shavings and cuttings 140 that result from the drilling action. These cuttings are carried up to the surface from downhole along an area between the drillstring and the borehole wall known as the annulus 150 . At the surface, the drilling mud is then cleaned, filtered and recycled for repeated use.
One problem occurs when the ports or nozzles on the face of the drill bit 125 become blocked or otherwise impeded from spraying drilling mud out the face of the drill bit 160 . This prevents or substantially slows the flow of mud to the surface, resulting in the rock cuttings falling to the bottom of the wellbore. It also results in a pressure build-up in the mud contained in the drill string. The increase in pressure can damage equipment uphole such as pumps. To minimize this problem, it is known to provide a circulating sub 170 that provides an alternate route 165 for drilling mud flow when the mud is unable to exit drill bit 160 properly.
Referring to FIG. 2, a known circulating sub 200 is called a ball-drop circulating sub. It includes a cylindrical valve sleeve 210 having holes or ports 220 . At its lower end is a lip 230 that reduces the inner diameter of the cylindrical valve sleeve 210 . The circulating sub housing surrounds valve sleeve 210 and also includes ports 225 . Shoulder 260 is positioned for abutment against the lower portion of valve sleeve 210 , as explained below. Between valve sleeve 210 and drill string 120 are o-rings 240 - 242 and a shear pin 250 . Ball 270 is shown falling in mid-travel from the surface before lodging in area formed by lip 230 .
During normal operation (i.e., when mud is properly flowing 160 through the drill bit 125 ), drilling, mud 130 flows through the center of circulating sub 200 as shown by arrows 280 . However, upon a blockage in the flow of mud, a ball 270 is shot from the surface down to ball-drop circulating sub 200 . Ball 270 lodges against lip 230 , preventing the flow of mud 130 along flow path 280 . Pressure built up in the mud column exerts itself against ball 270 and causes shear pin 250 to break. Valve sleeve 210 drops down until stopped by shoulder 260 . This aligns ports or holes 220 and 225 . Drilling mud 130 then escapes circulating sub 200 and follows mud path 165 (shown in FIG. 1) to the surface. This lifts the rock cuttings above the circulating sub 200 to the surface. However, the ball-drop circulating subs have a number of problems. For example, because the ball 270 originates at the surface, it can take up to thirty minutes from the time the mud flow stops through a drill bit to the time the circulating sub redirects the flow. In addition, this design is a one-time actuation and cannot be reset.
Other circulating subs having various problems, such as U.S. Pat. No. 5,465,787, are also presently known.
SUMMARY OF THE INVENTION
A preferred embodiment of the present invention features a downhole circulation sub having an electric motor associated with a valve poppet. The valve poppet moves from a first position to a second position in response to force from the electric motor, causing drilling fluid flowing through the circulation sub to switch its path of travel from a first route generally downwhole to a second route generally uphole. In its second position, the valve sleeve may engage a valve plug. Further, the valve poppet may be placed back in its first position by operation of the electric motor. The circulation sub is designed so that this movement of the valve sleeve from its first to its second position, and back again, may be carried out repeatedly.
Another aspect to the invention is a method of redirecting the flow of drilling fluid in a circulation sub. This aspect of the invention includes actuating an electric motor to apply force to a connected valve sleeve, moving the valve sleeve from a first position inside a housing to a second position by actuation of the electric motor, preventing by movement of the valve sleeve to the second position the flow of fluid past a lower end of the circulation sub, and directing by the movement of the valve sleeve to the second position the flow of fluid through ports positioned between the valve sleeve and an annulus. The first position is typically an upper position with respect to a wellbore, and the second position is a lower position.
Thus, the present invention comprises a combination of features and advantages which enable it to overcome various problems of prior devices. The various characteristics described above, as well as other features, will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention, and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more detailed description of the preferred embodiment of the present invention, reference will now be made to the accompanying drawings, wherein:
FIG. 1 illustrates the typical flow of drilling fluid in a borehole.
FIG. 2 depicts the operation of a ball drop circulating sub.
FIGS. 3A and 3B is a cut-away view of the preferred embodiment of the invention.
FIG. 4A is a cut-away view of the valve sleeve of the preferred embodiment in a closed position.
FIG. 4B is taken along line A—A of FIG. 4 A.
FIG. 5 is a cut-away view of the valve sleeve of the preferred embodiment in an open position.
FIG. 6 is a cut-away diagram of a second embodiment of the invention.
FIG. 7 is a block diagram of a third embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 3A and 3B generally show the operation of the preferred embodiment. A fluid circulating sub 300 according to the preferred embodiment is attached to drill string or other housing 320 . The circulating sub 300 includes a DC motor 310 with associated downhole circulating sub electronics 308 , the DC motor 310 being mechanically coupled to rotate threaded screw 330 in either direction. Nut 340 terminates in piston 335 . Nut 340 threadably affixes to screw 330 , and moves laterally as shown by arrow 345 upon the rotation of the screw by motor 310 . Chamber 350 terminates at its narrow end at piston 335 and at its wide end at piston 360 . Piston 360 connects to connecting rod 365 . Also shown in FIG. 3A are mud passage 305 around the perimeter of the circulating sub, oil compensation spring 355 , oil compensation piston 357 , and fail-sate spring 367 .
FIG. 3B also illustrates drillstring 320 and connecting rod 365 . Additionally shown are valve sleeve 370 , also known as a valve poppet, formed to sealably engage valve seat 375 . Valve seat 375 , also called a valve plug, may be mounted by use of a screw, for example, and includes an o-ring 378 to form a seal with valve sleeve 270 . Holes 380 and 381 for mud flow 390 into the center of the circulating sub are formed in the upper portion of valve sleeve 370 . Holes 382 and 383 in valve sleeve 370 correspond to holes 384 and 385 in the housing and provide an alternate route for the drilling mud when the circulating sub is open and activated. The housing is a circulating sub housing that engages with the valve sleeve, but may be any appropriate housing such as a section of the drill string. In addition, many of the advantages of the preferred embodiment may still be obtained even where the valve poppet is not exactly like the configuration shown. The valve poppet can therefore be any of a variety of configurations.
During operation, downhole circulating sub electronics 308 receive power from the surface. To facilitate power delivery, the system may be preferably part of a coiled tubing drillstring equipped with electric wiring. Alternatively, the system may be part of a slim-hole jointed drill pipe string, for example, or may be any other structure suitable to deliver power downhole. Real-time data communications from the surface are also sent to the downhole circulating sub electronics. In response, the electronics 308 control the operation of electric motor 310 . Electric motor 310 is preferably a DC motor, although this is not crucial to the invention. The electric actuation motor 310 is reversible and may turn screw 330 in either direction to repeatedly open and close the circulating sub 300 . As such, the circulating sub disclosed herein has a longer life span than circulating subs known in the prior art. It also does not require replacement when the drillstring is “tripped”, or removed from the well bore. It is therefore more economical than circulating subs known in the prior art.
As electric motor 310 turns screw 330 , the nut 340 moves laterally 345 by force of threaded screw 330 . This moves piston 335 within chamber 350 . Chamber 350 includes both a smaller cross-sectional end for piston 335 and a larger cross-sectional end for piston 360 . As screw 330 is actuated (i.e., moves from left to right in FIG. 3 B), it applies force to clean hydraulic fluid filling chamber 350 . This fluid transmits the force from piston 335 to piston 360 . What results is a hydraulic intensifier requiring less torque from, and thus less instantaneous current for, DC motor 310 . As force is applied to piston 360 , connecting rod 365 moves laterally in opposition to fail-safe spring 367 . In case of power failure, fail-safe spring returns the connecting rod 365 , and hence the circulating sub, to its unactuated and closed position.
Surrounding chamber 350 is an oil compression spring to resist the collapsing force from the drilling mud under high pressure and traveling through passage 305 . Oil compensation piston 357 accounts for the expansion and contraction of the hydraulic fluid due to temperature variations.
When valve sleeve is in its unactuated position as shown in FIG. 3B, drilling mud flows through holes 380 and 381 and follows mud path 390 past valve seat 375 and down to a drill bit, where it exits and travels up to the surface. The movement of connecting rod 365 from left to right opens the circulating sub by movement of valve sleeve 370 .
When this occurs, valve sleeve 370 covers and seals with valve seat 375 by, for example o-ring seal 378 . This movement of the valve sleeve aligns holes 383 and 385 , and holes 382 and 384 , respectively, to provide an alternate mud flow path to the annulus. This alternate mud flow path bypasses the downhole drill bit and provides direct access to the annulus for the drilling fluid. It would now be apparent to the artisan of ordinary skill that the valve plug need not necessarily engage within the valve sleeve exactly as shown, but rather that other appropriate geometries and structures could be used, so long as the valve sleeve engages to prevent flow of drilling fluid past the circulation sub.
FIG. 4A includes a connecting rod 365 that connects to sliding sleeve valve 370 . Sleeve valve 370 resides in nozzle sub 420 and lower sub 320 . Valve body 470 includes a bypass chamber 410 and wire channel 520 , as well as containing plug valve 275 . Sleeve valve 370 prevents the flow of mud into the bypass chamber 410 and forces the flow of drilling mud 390 past valve plug 375 toward a downhole assembly. Wires in wire channel 520 supply power downhole. Thus, like FIG. 3, FIG. 4A depicts the valve assembly in a closed position. FIG. 4B is taken along line A—A of FIG. 4 A.
FIG. 5 shows the valve assembly in an open position. Connecting, rod 365 attaches to sliding sleeve valve 370 . A seal between these two components is made by o-ring seal 378 . As can be seen, mud flow is prevented from going past valve plug 375 and instead is directed to bypass chamber 410 and out replaceable nozzles 430 . These nozzles 430 are angularly mounted with the centerline, creating a spiraling fluid stream that is effective to lift and transport cuttings out of the borehole for hole cleaning purposes. Further, because all bore fluid flow is cut off from the lower port of the bottomhole assembly, all of the drilling mud is forced to circulate to the annular region between the drillstring and the borehole wall. This results in the cuttings in the borehole above the circulating sub being circulated to the surface (where they can be cleaned from the drilling fluid) prior to the tripping or removal of the drill string from the borehole.
FIG. 6 illustrates a second embodiment of the invention. This circulating sub 600 includes an electric motor 610 attached to a lead screw 630 . The lead screw 630 attaches to a valve sleeve 670 . Hence, this embodiment does not use hydraulic force amplification. Instead, this embodiment uses direct mechanical actuation involving the advancing and retracting of a lead screw 630 by the electric motor 610 , the lead screw opening and closing the valve sleeve 670 .
FIG. 7 illustrates a third embodiment of this invention that does not include a connecting rod to associate the electric motor to the valve sleeve. An assembly inside a housing 720 includes an electric motor 710 associated with a valve poppet 770 . A translation means 730 applies from the electric motor 710 to the valve poppet 770 . Thus, a non-mechanical linkage, such as a hydraulic arrangement, may be used as the translation means 730 to open and close the downhole valve poppet 770 by operation of the electric motor 710 .
While preferred embodiments of this invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit or teaching of this invention. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the system and apparatus are possible and are within the scope of the invention. Accordingly the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims.
|
A preferred novel circulating sub includes an electric motor, hydraulic intensifier, connecting rod, valve sleeve, valve plug, and angled nozzles. Upon activation of the circulating sub the electric motor drives the valve sleeve over the valve plug, causing a flow of drilling fluid to exit the angled nozzles. Upon deactivation of the circulating sub, the electric motor removes the valve sleeve from the valve plug, allowing the flow of drilling fluid to once again flow to the drill bit. Because the electric motor is reversible, the circulating sub can be repeatedly activated and deactivated.
| 4
|
BACKGROUND OF THE INVENTION
[0001] The invention relates to an endoscope.
[0002] Without limiting its general application, the endoscope according to the invention is particularly suitable for tracheotomy. An endoscope used for this purpose is also referred to as a tracheoscope or bronchoscope.
[0003] In a tracheotomy procedure, when a patient whose normal breathing through the nose and mouth is impaired or no longer possible, an artificial route of respiration is established through the throat below the larynx. To do this, a trocar is used to create, from the outside, an incision through the throat and into the trachea, into which a tracheotomy cannula is later inserted through which the patient then breathes or can be ventilated.
[0004] A difficulty that arises in an operation of this kind lies in determining the exact position of the incision for the subsequent tracheotomy cannula. For this purpose, as has been described in document DE 695 27 958 T2, an endoscope is introduced through the patient's mouth and into the trachea, where the distal end of the shaft of the endoscope comes to lie just below the larynx. Arranged in the known endoscope there is a light guide whose distal end, from a distal opening of the endoscope shaft, radiates light in the direction of the anterior wall of the trachea. A spot of light is then visible on the skin of the front area of the throat, and the illuminated area of the trachea is also made visible. By moving the endoscope or light guide, the light spot can now be positioned in such a way that it comes to lie between two cricoid cartilages or tracheal rings of the trachea. The cricoid cartilages or tracheal rings stand out from the rest of the tracheal wall by virtue of a different intensity or coloration of the light spot. As soon as the light spot is correctly positioned, the aforementioned incision through the skin and into the trachea can now be made by means of a trocar with the aid of the light spot.
[0005] The known endoscope has a light guide which is continuously straight and whose light-emitting window is cut obliquely in relation to the longitudinal axis of the light guide. This results in an obtuse angle of radiation of the light relative to the longitudinal axis of the light guide. Since the light is not radiated strictly to form a point but instead in an areal manner, the oblique incidence of light on the tracheal wall has the effect that the visible light spot is “smudged”. To ensure a perpendicular incidence of the beam of light on the tracheal wall, the known endoscope has to be held obliquely relative to the longitudinal axis of the trachea, but the confined spaces in the region of the larynx and mouth through which the endoscope is introduced means this is not possible. If the light spot visible from outside is smudged, however, the incision into the trachea for the subsequently inserted tracheotomy cannula cannot be made with pinpoint precision. If this incision is not formed with pinpoint precision, the result of the tracheotomy may be compromised.
SUMMARY OF THE INVENTION
[0006] An object of the invention is therefore to develop an endoscope of the type mentioned at the outset in such a way that it allows an incision to be made into the trachea with pinpoint precision.
[0007] According to the invention, an endoscope is provided, comprising an elongated tubular shaft for introducing into a body of a patient, the shaft having a longitudinal axis and a distal end, and further having an opening at the distal end. A light guide is arranged along the shaft and has a light-emitting distal end, the light-emitting distal end being arranged in the area of the opening of the shaft in order to radiate light from the opening. The light-emitting distal end of the light guide is angled relative to the longitudinal axis of the shaft by an angle in a range of about 70° to about 110°.
[0008] The angled arrangement, according to the invention, of the light-emitting distal end of the light guide relative to the longitudinal axis of the shaft means that the light is also radiated at an angle in the range of about 70° to about 110° relative to the longitudinal direction of the shaft, so that, even without the shaft of the endoscope being positioned obliquely, it is possible to produce, on the tracheal wall and on the skin of the throat area, a smaller light spot than is obtained merely with an obliquely configured window at the distal end of the light guide. Thus, the endoscope shaft can be introduced advantageously in the longitudinal direction of the trachea and does not have to be angled relative to the trachea. In this way, the advantage of pinpoint precision of the incision into the trachea at the desired site is achieved.
[0009] In a preferred embodiment, a light-emitting window of the light-emitting end of the light guide extends approximately parallel to the longitudinal axis of the shaft when the light guide is oriented parallel to the longitudinal axis of the shaft.
[0010] With a light-emitting window extending parallel to the longitudinal axis of the shaft, the light spot produced on the tracheal wall and on the skin in the throat area becomes even smaller and the incision into the trachea can therefore be made with even greater precision, because the incidence of the light beam is at least approximately perpendicular to the skin. By contrast, in the case of an oblique light-emitting window, as in the known endoscope, there is an inevitable smudging and increase in size of the light spot, which makes an incision with pinpoint accuracy difficult.
[0011] In another preferred embodiment, the distal end of the light guide is angled relative to the longitudinal axis of the shaft by an angle in a range of about 80° to about 180°, and in yet another preferred embodiment the light-emitting distal end of the light guide is angled relative to the longitudinal axis of the shaft by an angle of about 90°.
[0012] Especially by combination of a distal end of the light guide, set at a right angle, with a window which extends parallel to the longitudinal axis of the shaft and from which the light emerges, it is possible to produce a particularly small and sharp light spot on the tracheal wall and on the skin in the throat area, with the result that the formation of the incision can be effected with very great accuracy.
[0013] According to another aspect of the invention, an endoscope is provided, comprising an elongated tubular shaft for introducing into a body of a patient, the shaft having a longitudinal axis and a distal end, and further having an opening at the distal end. The opening of the shaft extends obliquely relative to the longitudinal axis of the shaft. A light guide is arranged along the shaft and has a light-emitting distal end, the light-emitting distal end being arranged in the area of the opening of the shaft in order to radiate light from the opening.
[0014] Preferably, an edge of the opening forms, with the longitudinal axis of the shaft, an angle in a range of about 10° to about 40°.
[0015] The surface area of the opening is increased by this strongly oblique positioning of the opening of the shaft relative to the longitudinal axis of the shaft. The increase in the surface area of the opening now has the advantage that the rear wall of the shaft is likewise increased in size in the area of the opening, and this results in an enlarged protective surface which, during insertion of the trocar into the trachea, advantageously avoids the trocar drilling through or damaging the opposite wall of the trachea. Also in the subsequent maneuvers involved in fitting the tracheotomy cannula in which instruments are inserted through the incision into the trachea, the rear wall of the shaft, increased in size by the aforementioned measure in the area of the opening, advantageously serves as protection against damage to the posterior wall of the trachea.
[0016] In this context, it is preferable and advantageous if the light-emitting distal end of the light guide is arranged or comes to lie in a proximal area of the opening when the light guide is inserted into the shaft.
[0017] It is particularly preferable if the edge of the opening forms, with the longitudinal axis of the shaft, an angle in a range of about 15° to about 25°.
[0018] In another preferred embodiment, the light guide is arranged or can be arranged in the interior of the shaft, and the light guide extends near a shaft wall which is directed away from the opening.
[0019] This measure has the advantage that the light guide as a whole can be made rigid and, despite the angled position of the light-emitting distal end, the diameter of the shaft of the endoscope is not greater than in conventional endoscopes of this kind.
[0020] In another preferred embodiment, the distal end of the light guide has such a length that it does not protrude from the opening.
[0021] The advantage of this is that, if the endoscope is introduced into the patient's body already together with the light guide, the light-emitting distal end of the light guide does not form an obstacle during the advance of the endoscope.
[0022] In another preferred embodiment, the light guide can be withdrawn from the shaft.
[0023] This measure has the advantage of improved cleaning of the endoscope, since the light guide, after withdrawal from the shaft of the endoscope, can be more thoroughly cleaned than if it were to be left in the shaft of the endoscope. Moreover, in some cases the light guide is not required for the whole operation, so that, after removal of the light guide, the shaft of the endoscope can be used for the insertion of other instruments, or of a traction wire used in the tracheotomy procedure, without the light guide forming an obstacle.
[0024] In another preferred embodiment, a coupling is present at the proximal end of the light guide and at the proximal end of the shaft for the purpose of securing the light guide on the shaft in a predetermined position of rotation of the light guide relative to the shaft.
[0025] In conjunction with the angled positioning of the light-emitting distal end of the light guide, this measure has the advantage that the light guide is always connected to the shaft in the correct position of rotation in relation to the opening of the shaft, such that the light-emitting distal end of the light guide faces toward the opening.
[0026] Further advantages and features will become evident from the following description and from the attached drawing.
[0027] It will be appreciated that the aforementioned features and the features still to be explained below can be used not only in the respectively cited combination, but also in other combinations or alone, without departing from the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] An illustrative embodiment of the invention is described in more detail below with reference to the drawings, in which:
[0029] FIG. 1 shows an endoscope in a side view and partially in longitudinal section;
[0030] FIG. 2 shows a shaft of the endoscope from FIG. 1 in a side view, with associated attachment parts at the proximal end of the shaft;
[0031] FIG. 3 shows a side view of a light guide of the endoscope from FIG. 1 on its own, with associated attachment parts at the proximal end of the light guide, the light guide in FIG. 3 being shown enlarged by comparison with FIG. 1 ;
[0032] FIG. 4 shows a side view of the endoscope from FIG. 1 , the light guide having been inserted into the shaft of the endoscope; and
[0033] FIGS. 5 a ) to c ) show schematic representations of three method steps involved in the use of the endoscope from FIG. 1 in the context of a tracheotomy.
DETAILED DESCRIPTION OF THE INVENTION
[0034] In FIGS. 1 and 4 , an endoscope for tracheotomy is provided with the general reference number 10 . It will be appreciated that the endoscope 10 can also be used in other medical disciplines.
[0035] Components of the endoscope 10 are shown separately in FIGS. 2 and 3 .
[0036] The endoscope 10 comprises a shaft 14 which has a longitudinal axis 12 and which, because of its length, is shown interrupted in the figures. The shaft 14 is in particular rigid. The longitudinal axis 12 is to be understood as the direction of longitudinal exension of the shaft 14 .
[0037] At a proximal end 16 , the shaft 14 has a coupling part 18 which will be described later and which is used to secure a light guide of the endoscope 10 ; a connector tube 20 which extends obliquely and is used for the insertion of auxiliary instruments, wires and the like; and a connector tube 22 which can be used, for example, for attachment of a ventilation line in the event of the endoscope 10 being used in a tracheotomy. FIG. 2 , which shows the shaft 14 separately, also indicates a channel 13 arranged on the outside of the shaft 14 and with a connector 15 for attachment of a line (not shown). The outer channel 13 , which has been left out in FIGS. 1 and 4 , is used for respiratory gas monitoring.
[0038] At the distal end, the shaft 14 has an opening 24 at which the shaft 14 opens out. An edge 26 of the opening 24 extends obliquely in relation to the longitudinal axis 12 of the shaft 14 and forms, with the longitudinal axis 12 of the shaft 14 , an angle α in the range of about 10° to about 40°, in the present illustrative embodiment about 20°.
[0039] A rear wall 28 of the shaft 14 , directed away from the opening 24 , is closed and extends over more than approximately half the circumference of the shaft 14 . The central surface line of the rear wall 28 as seen in FIG. 1 is slightly oblique in relation to the rest of the wall of the shaft 14 and in relation to the longitudinal axis 12 of the shaft 14 by an angle β, specifically pointing outward by a few degrees.
[0040] The endoscope 10 also comprises a light guide 30 , which is shown separately and on an enlarged scale in FIG. 3 .
[0041] The light guide 30 in FIG. 1 is arranged along the shaft 14 , specifically in the interior of the shaft 14 , near a wall 32 of the shaft 14 directed away from the opening 24 , and parallel to the longitudinal axis of the shaft 14 .
[0042] The light guide 30 is substantially rigid and has, for example, a metal sleeve in which optical fibers or another light-conducting medium (not shown) are contained.
[0043] At a proximal end 34 , the light guide 30 has a coupling part 36 which cooperates with the coupling part 18 of the shaft 14 to secure the light guide 30 on the shaft 14 . The coupling part 18 and the coupling part 36 together preferably form a plug coupling, so that when the light guide 30 , which is withdrawable from the shaft 14 , is reinserted into the shaft 14 , it can be secured on the shaft 14 by simply plugging together the coupling parts 18 and 36 . The plug coupling is designed such that the light guide 30 can be coupled to the shaft 14 only in a specific position of rotation about its own longitudinal axis.
[0044] Moreover, the light guide 30 has, at the proximal end, a connector 38 for attachment of a fiber optic cable (not shown) via which light from an external light source can then be fed to the light guide 30 .
[0045] As can be seen from FIG. 1 , a light-emitting distal end 40 of the light guide 30 is angled relative to the longitudinal axis 12 of the shaft 14 , specifically by an angle in the range of about 70° to about 110°. In the preferred illustrative embodiment shown, the light-emitting distal end 40 of the light guide 30 is angled by 90° relative to the longitudinal axis 12 of the shaft 14 . A light-emitting window 42 of the light-emitting distal end 40 extends in particular approximately parallel to the longitudinal axis 12 of the shaft 14 .
[0046] As has already been mentioned, the light guide 30 can be withdrawn from the shaft 14 . FIG. 4 shows the reverse procedure, in which the light guide 30 has just been inserted into the shaft 14 . The light guide 30 is inserted into the shaft 14 until the coupling parts 18 (shaft 14 ) and 36 (light guide 30 ) are in engagement with one another, as is shown in FIG. 1 .
[0047] FIGS. 5 a ) to c ) are schematic representations showing the use of the endoscope 10 in the context of a tracheotomy.
[0048] Reference number 44 designates a patient's trachea, shown in a stylized form.
[0049] A posterior wall 46 of the trachea, directed toward the back of the patient's throat, and an anterior wall 48 of the trachea, directed toward the larynx, are shown in a stylized form in the drawing. Cricoid cartilages or tracheal rings 50 , 52 , 54 , etc., are situated in the tracheal wall 46 , 48 .
[0050] In a first method step, shown in FIG. 5 a ), the endoscope 10 with the shaft 14 is introduced through the mouth and throat into the trachea 44 , and specifically to the extent that the opening 24 of the shaft 14 comes to lie more or less level with the first cricoid cartilages 50 to 54 and points in the direction of the anterior wall 48 of the trachea. In cases where the light guide 30 has not been fitted into the shaft 40 upon insertion of the endoscope 10 , the light guide 30 is introduced into the shaft 14 in the direction of the arrow 56 , specifically until the light-emitting distal end, which, as has been described above, is angled relative to the longitudinal axis 12 of the shaft 14 by about 90°, comes to lie level with the opening 24 and the window 42 points in the direction of the opening 24 . This is shown in FIG. 5 b ). The exact position of the light-emitting distal end 40 of the light guide 30 is shown in FIG. 1 , and it will be noted that the light-emitting window 42 is situated in the proximal area of the opening 24 in the final position of the light guide 30 in the shaft 14 .
[0051] If the light guide 30 is now supplied with light, the light emerges from the window 42 of the light guide 30 and produces a preferably sharply defined light spot 58 of small size on the anterior wall 48 of the trachea, which light spot shows through the patient's skin and can thus be seen from outside. The size of the light spot 58 is shown purely schematically in FIG. 5 b ), and in particular said light spot 58 can also cover the first cricoid cartilage 50 and the second cricoid cartilage 52 , such that these are discernible by way of the light spot, on account of the different intensity of these light spot regions occasioned by the cricoid cartilages 50 and 52 . As is shown in FIG. 5 b ), the light propagation direction 60 is substantially perpendicular to the longitudinal axis 12 of the shaft 14 of the endoscope 10 .
[0052] According to FIG. 5 c ), the sharply defined light spot 58 can now be used, with the aid of a trocar 62 placed on the light spot 58 showing through the patient's skin, to make a precisely targeted incision through the skin and then through the anterior wall 48 of the trachea, without damaging the cricoid cartilages 50 , 52 , 54 , etc.
[0053] By virtue of the oblique formation of the opening 24 that runs toward a point, and by virtue of the resulting large surface area of the rear wall 28 of the shaft 14 in the region of the opening 24 , the trocar 62 , when advanced farther in the direction of an arrow 64 , strikes the rear wall 28 , and the rear wall 28 thus reliably ensures that the posterior wall 46 of the trachea is not also pierced.
[0054] FIG. 5 c ) also shows clearly that, even when the trocar 62 is inserted obliquely, as is indicated by broken lines, the trocar 62 is still effectively stopped by the rear wall 28 of the opening 24 and cannot damage the posterior wall 46 of the trachea.
[0055] In subsequent method steps too, in which further instruments are introduced through the incision created with the trocar 62 , the rear wall 28 safely protects the posterior wall 46 of the trachea from injury.
|
The invention relates to an endoscope, comprising an elongated tubular shaft for introducing into a body of a patient, the shaft having a longitudinal axis and a distal end, and further having an opening the distal end. A light guide is arranged along the shaft and has a light-emitting distal end, the light-emitting distal end being arranged in the area of the opening of the shaft in order to radiate light from the opening.
| 0
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a portable and lightweight fluorescent lighting system suitable for use in the field of photography, television and motion pictures utilizing fluorescent lamps.
[0003] 2. Description of the Prior Art
[0004] U.S. Pat. No. 5,132,885 disclosed a portable fluorescent lighting system. This system comprised of 5 corrugated panels that formed the basis of a lighting fixture. The five panels were created from one piece of corrugated polypropylene plastic. The panels were established by removing two to three upright flutes and one skin of corrugation between each panel. The remaining material formed a living hinge joining the 5 panels. The ends of the panel contained a U channel that carried a flexible metal wire that acted as a retention mechanism for holding the orientation of the panels once they were positioned by the user. The lighting system became very popular in motion picture lighting applications. The hinge retention mechanism being made of flexible metal wire had a given life span due to metal fatigue. After the metal fatigue resulted in the failure of the wire it would have to be replaced. Improvements were made along the way in which the flexible wire was encased in a flexible metal shield. This shield prevented sharp bends in the wire that would lead to premature wire fatigue and failure and thusly extended the life span of the wire.
[0005] Attempts at improving on the wire retention mechanism were challenging in that the panels do not pivot on a central point. Instead they pivot from one side of the living hinge. The original wire retainer concept was very low cost and very light weight. Applying conventional hinges to the fixture design never worked due to the pivot centers always being off center. Replacing the living hinge with a conventional hinge dramatically increased the cost and weight of the fixture as well as assembly costs. There was never a viable solution to improving on the hinge.
[0006] Various attempts have been made by others to construct a low maintenance hinge retention mechanism for this style of fixture. Film Gear, a Chinese manufacturer constructed a mechanism that comprised many parts that added weight and was costly to construct. They relied on a complex series of broad shallow U channels in which conventional hinge elements would slide back and forth under tension. The panels relied on the tension of the sliding hinge elements binding with the edges of the U channel. Over time this tension would lessen and fail to support the panels. The high assembly cost, weight and limited mobility of the mechanism were not considered a product enhancement. The performance of this hinge over time did not live up to the claims of superiority. When it required replacement the process was also labor intensive. This approach never found market acceptance.
SUMMARY OF THE INVENTION
[0007] The present invention addresses the issue of hinge wire maintenance by presenting a low cost high-tension mechanical retention hinge while not adding weight. The hinge construction takes into account the off center pivot point of the panels. It is designed for robust manipulation, low cost, ease of manufacturing and long tension life. It is designed for easy field replacement should the necessity ever arise.
[0008] The new design also allows for mounting pads to hold accessory honeycomb louvers used in directing the light as well as an accessory that blocks light from exiting the ends of the fixture.
[0009] This invention entails a lighting fixture having 5 panels. The invention has four primary elements:
[0010] 1. premolded central panel U channel with accessory holder;
[0011] 2. premolded outer subpanel U channel;
[0012] 3. premolded high tension retainer hinge;
[0013] 4. flexible light shield.
[0014] A premolded central U channel made of high impact plastic is mechanically fastened to the central and two secondary subpanel elements. This form is common to the opposing end of the fixture. The molded channels retain the three panels in a rigid trough configuration. The central panel U channel is configured to hold a lamp harness strain relief. The strain relief mechanism uses a ¼ turn fastener such as manufactured by Southco and a cable tie that wraps around the harness cable. The central panel U channel also has accommodation for an accessory holder for mounting lighting control louvers.
[0015] Premolded outer subpanel U channels are fastened to the four remaining panel ends. Each U channel includes a receiver channel designed to receive the piston arm of a retention hinge. It is sized so as to allow the piston arm to move freely with minimal friction.
[0016] A high-tension hinge retainer is made from a hinge mechanism that is commonly used by laptop computer manufacturers. This hinge mechanism is molded into two plastic piston arms. The arms are of two differing lengths. Each arm is designed to insert into receiver channels on the central U channel and the outer subpanel U channel. The arms include ridges or the like designed to fit snuggly into the channels yet provide minimal friction surface. The minimal friction allows free movement of the piston arms as the panels are oriented. The allowance for movement takes into account the panel displacement variances as the panels are manipulated. One of the piston arms has an oblong slot along the center. A fastening device such as a pin is inserted through the central U channel so as to capture the piston arm with a slotted end. The pin is removable to allow for replacement of the retainer hinge.
BRIEF DESCRIPTION OF THE INVENTION
[0017] FIG. 1 is a perspective view of the front of a fluorescent lighting system in accordance with the invention.
[0018] FIG. 2 is a perspective view of the rear view of the fluorescent fixture.
[0019] FIG. 3 is an exploded view of the premolded outer subpanel U channel, the premolded retainer hinges and the premolded central U channel form.
[0020] FIGS. 4 a - 4 e are detailed perspective views of the premolded retainer hinge.
[0021] FIG. 5 is a perspective view of a honeycomb light louver resting upon an accessory platform.
[0022] FIG. 6 is a partial perspective view of the fixture with a flexible and expandable opaque cloth light shield applied to the outside panels.
[0023] FIG. 7 is a perspective view of the front of a fluorescent lighting system in accordance with an alternate embodiment of the invention.
[0024] FIG. 8 is an exploded view of the premolded outer subpanel U channel, the premolded retainer hinges, the premolded inner subpanel U channel and the premolded central U channel form for the FIG. 7 embodiment.
[0025] FIG. 9 is a detailed perspective view of the three U channel forms as used in the FIG. 7 embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Referring to the figures in detail, FIGS. 1 and 2 are perspective views of the present invention. The invention comprises an elongated corrugated plastic panel 24 made into five subpanels by removing three flutes 17 (only one is shown) of the corrugation out to provide for hinging. The panel 24 includes center panel 12 at the center of said panel, a pair of inner subpanels 11 and 13 each on one side of center subpanel 12 , outer subpanel 10 positioned on the outer side of inner subpanel 11 , and outer subpanel 14 positioned on outer side of inner subpanel 13 . All subpanels 10 , 11 , 13 and 14 are symmetrically positioned and longitudinally extending in parallel to center subpanel 12 . Removal of two flutes 17 at each juncture of subpanels 10 / 11 and 13 / 14 provide for convenient and flexible hinging of subpanels without adding extra weight. The center panel may be reflective or an aluminum or other reflective material 21 may be placed under the lamps.
[0027] In order to prevent the subpanels from reverting back to their original positions after being flexed to a desired configuration, at each end of each outer subpanel 10 and 14 , a premolded U channel 15 in the shape of a rectangle is attached therein so that a one end of a flexible high tension hinge 16 having a substantially rectangular cross section may be easily inserted. The other end of the hinge 16 is inserted into the premolded central U channel 51 . Since hinge 16 is flexible, each subpanel can be manually positioned and held by the hinge in said position.
[0028] In the preferred embodiment, center subpanel 12 is always twice the width of the outer subpanels 10 and 14 . The fluorescent lighting source 22 is placed on the center subpanel 12 . Inner subpanels 11 and 13 and outer subpanels 10 and 14 are used to control the direction of and limit the output of the fluorescent lighting source 22 . Premolded center U channel 52 includes accessory platform and a ¼ turn lamp harness strain relief socket 53 that secures the lamp harness cord 18 .
[0029] FIG. 2 is a perspective view of the back of the fixture. A mating plate 43 is centrally located on the back of the fixture. The mating plate interfaces with mounting hardware allowing the fixture to be applied to an industry standard lighting stand. Two fixture strain relief loops 54 consisting of a high tensile strength aircraft wire are located at opposite corners positioned under the mating plate.
[0030] FIG. 3 is an exploded assembly perspective view of the two premolded U channel openings 58 and 59 and the retainer hinge 16 . The short piston leg 16 a of the retainer hinge 16 is inserted to receiver channel opening 58 and secured by a fastener pin 55 inserted through a hole 57 on the central U channel 51 . The long piston leg 16 b is inserted into receiver channel opening 59 . This is done by folding subpanels 10 and 14 back so they are substantially parallel to inner subpanels 11 and 13 . In this position, piston legs 16 a and 16 b can be inserted into receiver channels 58 and 59 simultaneously. The removable pin fastener 55 in the central U channel 51 allows for easy removal and replacement of hinge 16 such that in cases of damage or hinge fatigue, resulting in loss of tension, a new hinge can be inserted without having to replace the complete hinging assembly or the lighting system itself. This assembly is mirrored on the remaining four corners of the fixture. Retainer hinge piston 16 b is inserted into receiver channel 59 on outer subpanel U channel 15 . This assembly is mirrored on the remaining ends of the two outer subpanels 10 . The quarter turn lamp harness strain relief socket 53 is applied to central panel U channel 51 . This central U channel 51 is also applied to the opposite end of the fixture without inclusion of the strain relief socket 53 .
[0031] The U channels are affixed to their respective subpanels by suitable nuts and bolts, rivets or other fasteners known in the art (not shown in FIG. 3 but see FIG. 7 for an embodiment in which barrel nuts and bolts are used).
[0032] In FIGS. 4 a - 4 e , a series of perspective and cross sectional views of the retainer hinge 16 having a short piston 16 a and a long piston 16 b are shown. The short piston 16 a has an oblong hole 16 d for the fastening device. In this manner, slight adjustments can be made to the position of the short piston 16 a within channel 58 while keeping the short piston within the channel. This movement is necessary to accommodate the off center pivot point of the living hinges 17 . The long piston may also be adjusted within channel 59 , but due to its longer length, a fastening device as used for the short piston is not needed. Both pistons display cross section 16 c that ensures movement within the channels 59 and 58 with a minimum of friction.
[0033] FIG. 5 is a perspective view of the honeycomb light louver 61 resting upon the accessory platform 52 . A hook and loop fastener tab 60 is fastened to the frame of the light louver 61 . The fastener tab 60 adheres to its hook and loop opposite 56 that is adhered to the side of the accessory platform 52 . The light louver 61 has the hook and loop attachment mechanism recurrent on the remaining three corners.
[0034] FIG. 6 is a partial perspective view of the fixture and a flexible and expandable opaque cloth light shield 62 applied to the outside panels. A hook and loop fastener 64 is applied to the outside U channel 15 on both outside panels 10 and 14 . Another hook and loop fastener 65 is applied to the central U channel 51 . The mating hook and loop 63 and 66 is applied to the outside edges of the light shield 62 . The light shield 62 is applied in the same fashion at the other end of the fixture.
[0035] An alternate embodiment of the invention is illustrated in FIGS. 7-9 . As shown in FIG. 7 , instead of central U channel pairs 51 , U channel pairs 71 and 73 may be added to the ends of center panel 12 and inner subpanels 11 and 13 . As compared to the first embodiment shown for example in FIG. 2 , inner subpanels 11 (not shown in FIG. 2) and 13 instead of being in a fixed position relative to center panel 12 , in the FIGS. 7-9 embodiment, inner subpanels 11 and 13 may also be adjusted around a hinge formed between inner panel 11 /center panel 12 , and inner panel 13 /center panel 12 .
[0036] In particular, in place of central U channel 51 , U channel 73 is attached to each end of center panel 12 . U channel 71 is added to each end of inner subpanel 11 and inner subpanel 13 . U channels 73 and 71 are configured the same as sub channels 51 and 15 . That is, each U channel is placed over an end of its corresponding panel, and a flexible high-tension hinge 16 is inserted into openings in each of the U channels 73 and 71 as described above with respect to the insertion of hinge 16 with reference to FIG. 3 . Once the U channels and corresponding hinges are installed, the resulting hinges formed between center panel 12 , and inner subpanels 11 and 13 on the one hand, and the hinge formed between each inner and outer subpanel 10 / 11 and 13 / 14 may be adjusted to be in a desired position. The adjustment may be between zero and approximately 90 degrees by the hinges formed between center panel 12 , and inner subpanels 11 and 13 , and between approximately zero degrees and 135 degrees by the hinges found between inner/outer subpanels 10 and 11 , and 13 / 14 .
[0037] Each of the U channels may be secured by the use of slotted barrel nuts 83 and barrel bolts 85 . In this manner, in addition to securing the U channels to its respective panel, since the barrel nuts and barrel bolts have an open central bore, each nut/bolt pair may be used as a screw point to secure the fixture to a wall when the fixture is used in a studio or on location. The barrel inside diameter should be sufficient to allow, for example, a drywall screw to be inserted so that the panel may be secured to a wall. When such drywall screws are removed, then the fixture may be moved, closed for transport, and be available for subsequent use. Additionally, the barrel nut/bolts allow for easy removal of each of the U channels for replacement or repair of a damaged U channel or hinge.
[0038] The foregoing description is intended to provide a detailed explanation how to make and use the invention. However, such description is not intended to limit the scope of the invention as defined in the following claims.
|
A hinge retaining mechanism for a fluorescent lighting system. A portable fluorescent lighting system which utilizes an extremely lightweight corrugated plastic panel made into 5 subpanels. At each end of the panel a U shaped channel is attached that forms the center panel and the opposing adjacent two panels into a trough or recessed pan. On each of the two remaining panels is attached another U shaped channel. Each of the U shaped channels includes a mechanism for supporting a high-tension mechanical hinge. The mechanical hinge is designed to float freely within the adjacent channel brackets. One part of the hinge is mechanically retained to the channel to prevent inadvertent removal of the hinge.
| 5
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.