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BRIEF DESCRIPTION OF THE DRAWINGS
[0001] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying drawing in which:
[0002] [0002]FIG. 1 is a block diagram representation of a mobile device in accordance with an embodiment;
[0003] [0003]FIG. 2 is a logical model of a mobile device in accordance with an embodiment;
[0004] [0004]FIG. 3 is a flowchart of a method in accordance with an embodiment; and
[0005] [0005]FIG. 4 is a block diagram of an interface in accordance with an embodiment.
[0006] It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the figure have not necessarily been drawn to scale. For example, the dimensions of some of the elements are exaggerated relative to other elements for clarity.
DETAILED DESCRIPTION
[0007] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present invention.
[0008] Some portions of the detailed description that follows are presented in terms of algorithms and symbolic representations of operations on data bits or binary digital signals within a computer memory. These algorithmic descriptions and representations may be the techniques used by those skilled in the data processing arts to convey the substance of their work to others skilled in the art.
[0009] An algorithm is here, and generally, considered to be a self-consistent sequence of acts or operations leading to a desired result. These include physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers or the like. It should be understood, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities.
[0010] Unless specifically stated otherwise, as apparent from the following discussions, it is appreciated that throughout the specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining,” or the like, refer to the action and/or processes of a computer or computing system, or similar electronic computing device, that manipulate and/or transform data represented as physical, such as electronic, quantities within the computing system's registers and/or memories into other data similarly represented as physical quantities within the computing system's memories, registers or other such information storage, transmission or display devices.
[0011] Embodiments of the present invention may include apparatuses for performing the operations herein. An apparatus may be specially constructed for the desired purposes, or it may comprise a general purpose computing device selectively activated or reconfigured by a program stored in the device. Such a program may be stored on a storage medium, such as, but not limited to, any type of disk including floppy disks, optical disks, compact disc read only memories (CD-ROMs), magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), electrically programmable read-only memories (EPROMs), electrically erasable and programmable read only memories (EEPROMs), Flash memory, magnetic or optical cards, or any other type of media suitable for storing electronic instructions, and capable of being coupled to a system bus for a computing device.
[0012] The processes and displays presented herein are not inherently related to any particular computing device or other apparatus. Various general purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct a more specialized apparatus to perform the desired method. The desired structure for a variety of these systems will appear from the description below. In addition, embodiments of the present invention are not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the invention as described herein.
[0013] In the following description and claims, the terms “coupled” and “connected,” along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. Rather, in particular embodiments, “connected” may be used to indicate that two or more elements are in direct physical or electrical contact with each other. “Coupled” may mean that two or more elements are in direct physical or electrical contact. However, “coupled” may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other.
[0014] Turning to FIG. 1, an embodiment 100 in accordance with the present invention is described. Embodiment 100 may comprise a portable computing or communication device 50 such as a mobile communication device (e.g., cell phone), a two-way radio communication system, a one-way pager, a two-way pager, a personal communication system (PCS), a personal digital assistant (PDA), a portable computer, or the like. However, it should be understood that the scope and application of the present invention is in no way limited to these examples. Other embodiments of the present invention may include other computing systems that may or may not be portable or even involve communication systems such as, for example, desktop or portable computers, servers, network switching equipment, etc.
[0015] In this particular embodiment portable communication device 50 may include an application subsystem 70 and a communication subsystem 80 that are coupled together by an interface 25 . Although the scope of the present invention is not limited in this respect, application subsystem 70 may be used to provide features and capabilities that are visible or used by a user such as, for example, email, calendaring, audio, video, gaming, etc. Communication subsystem 80 may be used to provide wireless and/or wired communication with other networks 60 - 61 such as, for example, cellular networks, wireless local area networks, etc.
[0016] An interface 25 may be used to provide communication or information between application subsystem 70 and communication subsystem 80 . Although the scope of the present invention is not limited in this respect, interface 25 may comprise serial and/or parallel buses to share information along with control signal lines to be used to provide handshaking between application subsystem 70 and communication subsystem 80 .
[0017] However, it should be understood that the use of interface 25 should be considered optional. In addition, the scope of the present invention is not limited so as to require both application subsystem 70 and communication subsystem 80 . In alternative embodiments, a portable communication device may have just one or the other. Further, yet other embodiments may have one processor that provides the capabilities of both.
[0018] In this particular embodiment, application subsystem 70 may include a processor 10 that may execute instructions such as instructions stored in a memory 40 . Processor 10 may be one of a variety of integrated circuits such as, for example, a microprocessor, a central processing unit (CPU), a digital signal processor, a microcontroller, a reduced instruction set computer (RISC), a complex instruction set computer (CISC), or the like, although the scope of the present invention is not limited by the particular design or functionality performed by processor 10 . In addition, in some alternative embodiments, application subsystem 70 may comprise multiple processors that may be of the same or different type.
[0019] Portable communication device 50 may also comprise memory 40 that may comprise any variety of volatile or non-volatile memory such as any of the types of storage media recited earlier, although this list is certainly not meant to be exhaustive and the scope of the present invention is not limited in this respect. Memory 40 may comprise persistent memory to be used to store sets of instructions such as instructions associated with an application program, an operating system program, a communication protocol program, etc. For example, the instructions stored in memory 40 may be used to perform wireless communications, provide security functionality for portable communication device 50 , user functionality such as calendaring, email, internet browsing, etc.
[0020] Application subsystem 70 may also comprise a display 20 to provide information to a user and communication modules 30 - 31 to provide access to other devices, service, networks, etc. Alternatively or in addition, application subsystem may include other components such as input/output devices, audio outputs, etc. However it should be understood that the scope of the present invention is not limited so as to require any particular combination of components shown in FIG. 1.
[0021] Communication subsystem 80 may include a baseband processor 39 , such as one of the types described above and communication modules 30 - 31 that may be used to allow portable communication device 50 to communicate with other networks through either a wired or wireless link. As shown, communication modules 30 - 31 may use antennae 34 - 35 to wirelessly communicate with networks 60 - 61 .
[0022] Although the scope of the present invention is not limited in this respect, communication modules 30 - 31 may employ a variety of wireless communication protocols such as cellular (e.g. Code Division Multiple Access (CDMA) cellular radiotelephone communication systems, Global System for Mobile Communications (GSM) cellular radiotelephone systems, North American Digital Cellular (NADC) cellular radiotelephone systems, Time Division Multiple Access (TDMA) systems, Extended-TDMA (E-TDMA) cellular radiotelephone systems, third generation (3G) systems like Wide-band CDMA (WCDMA), CDMA-2000, and the like).
[0023] In addition, communication modules may use other wireless local area network (WLAN), wide area network (WAN), or local area network (LAN) protocols such as the Industrial Electrical and Electronics Engineers (IEEE) 802.11 standard, Bluetooth™, infrared, etc. (Bluetooth is a registered trademark of the Bluetooth Special Interest Group).
[0024] It should be understood that the scope of the present invention is not limited by the types of, the number of, or the frequency of the communication protocols that may be used by portable communication device 50 . Furthermore, alternative embodiments may have more than two communication modules (either wired or wireless) and communication modules need not have separate antennae, and some or all may share a common antenna.
[0025] It should also be understood that communication subsystem 80 may include other optional components such as, for example, a vocoder 37 to encode voice data or memory 38 Memory 38 may comprise one or more of the memory types described above.
[0026] Turning to FIG. 2, a particular embodiment of the present invention is provided. FIG. 2 is a logical model diagram representing the relationships and interactions between operations that may take place within portable communication device 50 . It should be understood that operations or features illustrated in FIG. 2 may be implemented with any combination of hardware and software. In other embodiments, operations shown in FIG. 2 and/or discussed below may be implemented entirely in hardware or entirely in software. Furthermore, the portions of the operations that are implemented, at least in part, with software may be implemented through an operating system, user applications, firmware, etc., although the scope of the present invention is not limited to just these examples.
[0027] Although the scope of the present invention is not limited in this respect, during the operation of portable communication device 50 , persistent memory 40 may be used to store files 41 - 43 that may comprise a variety of information to be used by portable device 50 . For example, files 41 - 43 may represent at least a portion of a user data file, operation system program, application program, security data,
[0028] It may be desirable to occasionally or periodically add files or data to memory 40 . For example, the user of portable communication device 50 may want to download information or a new program/resource into portable device 50 for storage in memory 40 . Prior to installing the new program or data, some of files 41 - 43 may be removed to provide for the additional storage. As explained in more detail below, portable communication device 50 may provide assistance in identifying which file or files 41 - 43 should be deleted so as to reduce the impact on the user.
[0029] Although the scope of the present invention is not limited in this respect, portable communication device 50 may maintain a library 200 of resource characteristics of the data or files stored within portable communication device 50 . The number or the extent of information stored in library 200 may vary, as desired, and include some or all of the following. For example, library 200 may comprise resource characteristics such as the usage of files 41 - 43 . The usage may be tracked so that the usage represents an actual usage. Alternatively, the usage may be predictive in nature based on various factors so that the usage may be predicted on the operational mode, user preferences, quality of service provided by a network, etc.
[0030] Additionally or alternatively, library 200 may maintain the source of files 41 - 43 , the cost to replace files 41 - 43 in portable communication device 50 ,or the amount of time to replace files 41 - 43 , although the scope of the present invention is not limited in this respect. For example, library 200 may keep track of where files 41 - 43 came from or where they are likely to be replaced from (e.g. network source, hardware source, etc.). The resource characteristics may also keep track of the costs in time, money, and/or convenience that may be incurred by the user of portable communication device 50 . For example, library 200 may maintain data such as the number of packets or amount of time it would take to replace the file, or alternatively, total amount that may be charged, etc, although the scope of the present invention is not limited in this respect.
[0031] Additionally or alternatively, library 200 may maintain resource characteristics associated with the amount of temporary memory space needed to execute files 41 - 43 , the relative ease to replace files 41 - 43 , and predicted usage of the first file. Although the scope of the present invention is not limited in this respect, portable communication device 50 may include a volatile memory 45 such as, for example, any of the volatile memory types described above.
[0032] During the operation of portable device 50 , at least some of the files 41 - 43 may be optionally copied to a volatile memory 45 for a variety of reasons. Although the scope of the present invention is not limited in this respect, files or data may be copied to memory 45 so that they may be altered or access faster by processor 10 . Consequently, library 200 may store information such as the size of the files, memory requirements, the type of the data or file (e.g. voice data, user data, program instruction, program data, etc.),or typical or average amount of memory used, etc.
[0033] It should be understood that the scope of the present invention is not limited to embodiments where the resource characteristics maintained are associated with files or data. In alternative embodiments, information or characteristics for other features of portable communication device 50 may also be maintained. For example, library 200 may comprise information associated with other software features such as applets, cookies, etc. Additionally or alternatively, library 200 may comprise information associated with the hardware of portable communication device 50 such as, for example, display 20 , processing capabilities, network connectivity hardware, peripheral resource availabilities, etc.
[0034] With reference now to FIG. 4, a particular embodiment of the present invention is provided. Although the scope of the present invention is not limited in this respect, in this particular embodiment an interface may allow components to be developed separately from one another and still be able to interoperate with one another successfully. FIG. 4 illustrated one or more clients 401 that may be coupled to an interface 402 . Examples of clients 401 may include, but are not limited to, Application Installers, Applications, Application Downloaders, Backup/Restore utilities, Application acquisition utilities such as a program that assists a user in shopping for and purchasing new applications, etc.
[0035] Interface 402 may provide a variety of operations 403 described in more detail below. The actual capabilities represented by the operations 403 are supplied by one or more libraries 404 . A library 404 may comprise one or more pieces of meta-data 405 that may give information about one or more Files 408 .
[0036] Although the scope of the present invention is not limited by the type of nature of meta-data 405 , in one particular embodiment meta-data 405 may record an association 407 between one or more files 408 and one or more resource type tags 406 . Interface 402 may predefine particular resource type tags 406 , and may allow extension of the set of resource type tags. For example, tags 406 may include but are note limited to: “application installation data”, “user data”, “application setting or configuration”, “temporary persistent storage”, “persistent storage”, “volatile storage (e.g. RAM)”.
[0037] Although the clients 401 , interface, 402 , operations 403 , library 404 , meta-data 405 , and files 408 are described as separate components for the purpose of illustration, one skilled in the art will recognize that these components may be integrated in a variety of ways that may not involve separation between one component and another. For example, it is possible that a single component may at times act in the role of a client 401 such as an installer and at other times act in the role of a library 404 .
[0038] Interface 402 may be embodied in a variety of different ways including but not limited to the following: a set of software procedures that may be called and that have a defined syntax and semantics, A set of messages and replies that may be sent and received and that have a defined syntax and semantics, A protocol for interaction between elements with defined syntax and semantics, or Serial or parallel busses along with control signal lines.
[0039] The set of operations 403 provided by the interface 402 may differ from one embodiment to another. Although the scope of the present invention is not limited in this respect, some embodiments may include: operations to install an application where there is an option to retain user data from a previous installation, or to create an empty user-data repository or subsequent restoration from archived user data, an operation to remove an application where there is an option to keep or remove associated user data or application settings or configuration, an operation to create, update, retrieve, and remove an association between a file (or other unit of storage) and one or more type classifications, an operation to create, update, retrieve, and remove an association between a user-data file and an application that is used to manipulate that user data, an operation to create, update, retrieve, and remove an association between a user-settings or configuration file and an application that shall behave according to those user-settings or configuration, an operation to create, update, retrieve, and remove an association between a storage resource requirement quantity, a storage resource type, and an application, an operation to retrieve the system's available resource quantities for storage resource type classifications, etc.
[0040] Similarly, the associations 407 that may be recorded by meta-data 405 may include types of associations corresponding to the operations described above. However, this set of operations or types of associations should not be construed as limiting. The set of operations or types of associations provided in other embodiments may omit some of these, and it may include functions or types of associations outside this set. Moreover, an embodiment may allow the set of operations or types of associations to be extended.
[0041] Similarly, meta data 405 may be embodied in a variety of different ways. Non-limiting examples of meta-data embodiments include: a data base, a data format within ordinary files, an attachment of auxiliary data to files, a technique that implicitly embodies the data in the structure of a file system (e.g., user-data for an application might be all in a sub-directory of the application's installation directory), putting the data in EEPROM or Flash, putting the data in a table, or putting the data in a registry.
[0042] With reference now to FIG. 3, a method in accordance with an embodiment of the present invention is provided. To begin, resource characteristics information may be created or maintained, box 300 . Although the scope of the present invention is not limited in this respect, resource characteristics information may be stored in library 200 as a data file, in a table, in registers/latches, etc. Alternatively, library 200 may represent a combination of both software and hardware, such as an application programming interface API, so that the particular storage mechanism is transparent to the hardware and/or software that provides the resource characteristics information.
[0043] Resource characteristics information may be provided from a variety of sources and it should be understood that the scope of the present invention is not limited by the source. For example, as files 41 - 43 are stored in memory 45 (see FIG. 2), the corresponding resource characteristics may be stored in library 200 . The information may come from the installation program (e.g. installer 35 ) that installed the program within portable communication device 50 or from the firmware, basic input/output software (BIOS), operating system, etc.
[0044] Additionally or alternatively, resource characteristics information may be provided dynamically while portable communication device 50 is in operation and after files 41 - 43 have been loaded into memory 45 . For example, processor 10 may provide or update resource information depending on the operational capabilities of portable communication device 50 that may change with time or as other hardware and/or software is added. Alternatively, a communication module 30 may update resource characteristics information that may be based, at least in part, on the network(s) with which portable communication device 50 is in communication.
[0045] Portable communication device 50 may then use all or at least a portion of the resource characteristics information of library 200 to prioritize files 41 - 43 , box, 301 , although the scope of the present invention is not limited in this respect. For example, the resource characteristics information may be used to identify which of files 41 - 43 should be deleted if more space is desired. Alternatively, files 41 - 43 may be prioritized in order of importance, order of increasing/decreasing cost to be incurred by a user to replace the files, increasing/decreasing order of the amount of time or inconvenience incurred by a user to replace the files through a wireless or wires connection, etc.
[0046] It should be understood that the scope of the present invention is not limited to how files 41 - 43 are prioritized using the resource characteristics in library 200 . In addition, it should be understood, that prioritization may occur when any of the resource characteristics are added/modified, or optionally, prioritization may occur periodically during the operation of portable communication device 50 . In yet other embodiments, prioritization may occur when library 200 is queried regarding the information stored in library 200 as part of a file management operation. In addition, it should be understood that the scope of the present invention is not limited to devices that perform prioritization. In other embodiments, the resource characteristics of library 200 may be used without performing any prioritization.
[0047] For example, although the scope of the present invention is not limited in this respect, library 200 may be queried by an operating system 60 if there is a need to move a file into memory 40 , update a file in memory 40 , or delete a file from memory 40 , box 302 . Alternatively, library 200 may be queried during other file management operations such as during a reclaiming operation of memory, as part of a backup operation, as part of an operation to relocate all or part of a file/data from memory 40 to memory 45 , or vice-versa, or other file management operations.
[0048] Additionally or alternatively, library 200 may be queried by the user of portable communication device 50 . This may be done, for example, if the user would like to add a new program, data file, hardware, software, service, etc. into portable communication device 50 . Thus, the user may decide for himself or herself what file management operations should be performed based on the information available by library 200 .
[0049] Optionally, portable communication device 50 may make a recommendation as to which of files 41 - 43 should be deleted. The recommendation may be based on a prioritization process as described above, box 301 , or may be made on other factors indicated to be important by the user. For example, the user may indicate that factors such as cost, download time, or security is very important and portable communication device 50 may poll library 200 and make a recommendation based on those factors. Thus, a file management operation may be performed (e.g. a file may be deleted) based on a recommendation provided by portable communication device 50 , or based on a decision made by the user, although the scope of the present invention is not limited in this respect.
[0050] It should be understood that the resource characteristics information stored in library 200 may be utilized by other hardware and/or software within portable communication device 50 . For example, the information may be used by a direct memory access (DMA) engine 65 to assist in the transferring of data, instructions, etc. within the memory system of portable communication device 50 . Alternatively, the resource characteristics information of library 200 may be used by external devices such as, for example, the network with which portable communication device is in communication.
[0051] In this particular embodiment, after a file management operation is performed, the corresponding resource characteristics information in library 200 may be updated, box 303 . For example, if a file as been added, modified, or move, the information may be updated accordingly, although the scope of the present invention is not limited in this respect. In addition, the resource characteristics information may be updated periodically or upon any changes within portable communication device 50 or the network.
[0052] While certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | Briefly, in accordance with one embodiment of the invention, a portable computing or communication device maintains a library of resource characteristics for files or data stored in the device. The characteristics may be used to identify which file should be deleted to make room for another file to be loaded. The characteristics may reflect information about how much of a cost or inconvenience a user may incur by having to later replace the deleted file. | 6 |
BACKGROUND AND SUMMARY OF THE INVENTION
The instant invention relates to apparatus for setting a tool in a well bore and more particularly to such apparatus in which the setting of the tool is accomplished with hydraulic pressure.
The instant invention can be used to set in a well bore a packer of the type having a conduit therethrough and to thereafter selectively connect and disconnect a pipe or tubing string to the packer conduit. The packer is of the type having elastomeric material disposed about the conduit and further having upper and lower slip assemblies positioned above and beneath the packing material. The conduit includes a valve having an internal sliding sleeve which is selectively movable between one position permitting fluid flow through the conduit and another position shutting off such flow.
Past setting tools have been proposed for setting such packers. One past tool includes a mandrel for inserting into the packer conduit for opening and closing the sleeve valve, an inner sleeve which supports the mandrel and connects it to the conduit string, and a screw jack device disposed between the inner sleeve and an outer setting sleeve.
In setting the above-described packer with the prior art tool, a string is made up wherein the setting tool is connected by its inner sleeve to a tubing string, a breakable tension sleeve is threadably engaged between the lower end of the setting tool and the upper end of the packer conduit, and the setting tool mandrel extends into the packer conduit to maintain a slidable valve in an open position while the tubing string is lowered into the well. When the desired depth for setting the packer in the casing is reached, the tubing string is rotated a predetermined number of times, which rotation operates the screw jack device, thus forcing the setting sleeve downwardly to set the upper packer slips against the sides of the bore. Tension is applied with the tubing to set the lower slips and break the tension sleeve. This leaves the packer engaged in the bore and the setting tool suspended on the tubing string thereabove. Thereafter, the mandrel may be stung into the packer conduit for actuating the valve to provide fluid communication between the tubing string and the bore beneath the packer.
Such past setting tools have proved somewhat unsatisfactory due to their mechanical complexity as well as the necessity for substantial amounts of vertical and rotational movement of the pipe or tubing string and loading of the string in order to set the packer.
Past apparatus have been proposed for setting liner hangers in which hydraulic pressure is used to effect setting. One such apparatus includes an annular collar disposed about a mandrel which is suspended from a tubing string. A ball is dropped down the tubing string to seal the string beneath the collar. A port connects the tubing string to the annulus between the collar and the mandrel and when the string is pressurized, the collar moves upwardly. Setting slips disposed on an inclined surface are suspended from the collar and upward movement along the surface urges the slip outwardly to set the hanger. Such past liner hangers are not adaptable for setting packers of the type above described and do not include a mandrel for actuation of the sliding packer valve.
The instant invention includes inner and outer sleeves telescopically interengaged and adapted to be suspended from a pipe or tubing string for lowering into a well bore. A shearable tension sleeve connects a packer of the above-described type to the lower end of the inner sleeve. A vertically shiftable mandrel is received within the inner sleeve for engaging the packer valve. A ball and groove device disposed between the inner sleeve and the mandrel maintain the mandrel in a fixed position relative to the sleeve. Pressurization of a hydraulic chamber disposed between the inner and outer sleeves urges the inner sleeve upwardly thus shearing the tension sleeve and setting the tool. Such upward movement causes movement of the ball to permit downward movement of the mandrel relative to the inner sleeve. Thereafter, the mandrel may be stung into the packer conduit for actuating the valve as desired.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1F are successive downward continuations, shown partly in quarter-section and partly in half-section, of the preferred embodiment of the invention combined with a circulating valve, drag blocks and a packer.
FIG. 2 is an enlarged view of a portion of the view of FIGS. 1D and 1E after setting of the packer.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to FIGS. 1A-1F, indicated generally at 10 is a setting tool which incorporates the preferred embodiment of the invention. Setting tool 10 is used to set a well tool or packer, indicated generally at 12, in the bore of a well. Setting tool 10 is set up on a string which includes (from the bottom up): packer 12, setting tool 10, a drag block assembly indicated generally at 14 and, mounted on the top of the drag block assembly, a conventional circulating valve indicated generally at 16. The circulating valve is connected to a conventional coupler 18 which include threads 20 for connection to a tubing string (although a pipe string may easily be used instead) for lowering the string into a well bore to set the packer.
Circulating valve 16 may be of the type shown in U.S. Pat. No. 3,315,747 to Farley et al. and assigned to the assignee of the instant application. Examination of the Farley patent may be made for a detailed description of the structure and operation of the circulating valve. Circulating valve 16 includes an inner mandrel 22. Mandrel 22 is generally cylindrically shaped and is connected to coupler 18 via threads 24. The mandrel includes radially opposing lugs, one of which is lug 26, which extend outwardly from the mandrel surface. Also included in the mandrel is a plurality of ports, indicated generally at 28 which extend through the mandrel about its circumference.
A J-slot sleeve 30 extends about the circumference of inner mandrel 22 and includes a J-slot indicated generally at 32 having an upper portion 34 and a lower portion 36. The J-slot is formed on the radially inner side of the J-slot sleeve and is constructed to permit lug 26 on the inner mandrel to be received within the upper or lower portion and to be moved between the two portions by means of longitudinal and rotational movement of inner mandrel 22. The J-slot sleeve is threadably connected to a valve body 38 via threads 40. Valve body 38 is cylindrically shaped and includes ports, like ports 40, 42, about its circumference. Valve body 38 also includes an annular space 44 formed completely about the circumference of the valve body radially inward from the ports. As can be seen in FIG. 1A, space 44 permits fluid communication between inner mandrel 22 (via ports 28 of the inner mandrel) and the well bore into which the valve is lowered regardless of the radial orientation of the inner mandrel. A lower valve body 45 is threadably connected via threads 46 to the lower end of valve body 38. Lower valve body 45 includes threads 48 at its lower end which threadably engage the lower valve body to a drag block mandrel 50. Drag block mandrel 50 is substantially cylindrically shaped and includes six openings, like opening 52, which are equally spaced about the circumference of the drag block mandrel. Each opening contains a drag block and associated structure like drag block 54 in opening 52. Drag block 54 is radially biased outwardly by a spring 56. Each of the drag blocks includes a plurality of disks, like those indicated generally at 58 on drag block 54 for engaging the surface of a well bore in order to increase the coefficient friction between the drag blocks and the well bore surface. A keeper, like keeper 60, is mounted on mandrel 50 at the lower end of each drag block to maintain the drag blocks in their respective openings.
As will later become more fully apparent in discussing the operation of the string depicted in FIGS. 1A-1F, drag block assembly 14 serves to resist movement of the outer cylindrical portion of circulating valve 16 including lower valve body 45, valve body 38, and J-slot sleeve 30. When the drag blocks engage the surface of a well bore, longitudinal and rotational tubing string movement may be used to shift lug 26 on inner mandrel 22 to lower portion 36 of the J-slot. Such inner mandrel movement effects downward sliding of ports 28 on the mandrel for sealing off from ports 40 on valve body 38 to shut off fluid communication between inner mandrel 22 (and hence the conduit tubing to the surface) and the well bore via ports 40. Thereafter, the inner mandrel may be manipulated by tubing movement in order to shift ports 28 upwardly to the configuration shown in FIG. 1A to permit such fluid communication.
Included in setting tool 10 is a setting or outer sleeve 62, such having a generally cylindrical shape and being threadably engaged with drag block mandrel 50 via threads 64. The setting sleeve includes a downward facing annular shoulder 66. A bore 68 permits fluid communication between the interior of the setting sleeve and the well bore. A radially inward extension or annular piston 70 extends about the inner circumference of the setting sleeve. A second bore 72 is formed in the sleeve beneath piston 70. A second piston 74 is positioned beneath piston 70 and extends about the interior of the sleeve like piston 70. A third bore 76 (FIG. 1E) is located at the lower end of the setting sleeve. The bottom of the setting sleeve includes an annular tapered surface 78 which, as will later be more fully apparent, is provided for engaging structure on packer 12 for setting the packer.
Contained within setting sleeve 62 is an inner sleeve 80. Inner sleeve 80 is in sealing engagement with the outer sleeve at several locations, one of which is provided by an O-ring 82. The inner sleeve includes radially outward extensions or pistons 84, 86. Each piston is annular shaped and is in sealing engagement about its circumference with the radially inner surface of setting sleeve 62 via O-rings 88, 90. Likewise, pistons 70, 74 on the setting sleeve include O-rings 92, 94 for sealing pistons 70, 74 to the radially outer surface of inner sleeve 80. The spaces between pistons 84, 70, and between pistons 86, 74 define hydraulic chambers 96, 98. Each hydraulic chamber includes a bore 100, 102 which connects its associated chamber to the interior of sleeve 80. The interior of inner sleeve 80 includes two downward facing annular shoulders 104, 106, each of which extends about the circumference of the sleeve, and an upward facing annular shoulder 108, such also extending about the circumference of the sleeve.
A plurality of slots, like slots 110, are formed in sleeve 80 beneath shoulder 108. Each slot permits communication between the interior and exterior of the sleeve and each includes a ball, like ball 112 in slot 110. The balls are maintained in their slots by a locking collar 114 which extends about the circumference of inner sleeve 80 and covers each of the slots.
Collar 114 is maintained in its place by a plurality of shearable means or shear pins, one of which is shear pin 116. Each pin is received within radially aligned bores formed in inner sleeve 80 and in locking collar 114. As will later be explained, when sufficient downward force is applied to locking collar 114 with respect to the inner sleeve, the shear pins shear and permit the locking collar to slide along the sleeve.
The locking collar further includes an annular groove 118 formed about the inner circumference of the collar. An O-ring 120 rests on the top of collar 114. Piston 74, located above O-ring 120, includes a lower surface 122 which is referred to herein as stop means. A lock ring 124 is received within a radially inward facing channel 126 formed at the lower end of locking collar 114. A second channel 128 is formed about the circumference of inner sleeve 80 at its lower end.
In FIG. 1D, a mandrel 130 is received within inner sleeve 80. The mandrel includes a bore 132 which places the interior of the mandrel in fluid communication with an annular space between the mandrel and the radially inner side of inner sleeve 80. An upward facing shoulder 134 is formed about the circumference of mandrel 130 beneath bore 132. An O-ring 136 beneath shoulder 134 seals the mandrel to the radially inner surface of inner sleeve 80 about the circumference of each. A spring 138 is compressed in the annular space between shoulders 134, 106. Annular grooves 140, 142 are formed on the radially outer surface of the mandrel about its circumference. Groove 140 receives each of the balls, like ball 112. Each ball is maintained in the groove by locking collar 114 thus preventing relative longitudinal movement between the mandrel and inner sleeve 80. Groove 142 is wider than groove 140 and is referred to herein as a second groove. Mandrel 130 extends downwardly into packer 12. Packer 12 is connected to the lower end of inner sleeve 80 via a tension collar 144 (also referred to herein as attaching or shear means). Collar 144 includes threads 146, 148, such connecting the collar to inner sleeve 80 and to a packer conduit 150, respectively. Tension collar 144 also includes a narrowed portion 152 which, as will later be explained, breaks during setting of packer 12 in order to separate the setting tool from the packer.
Packer 12 is of conventional structure and includes a split ring 154 which, in the condition shown in FIG. 1E, maintains slips such as slips 156, 158 in an upper position as shown. The slips are suspended from an annular lock ring housing 159. A conventional annular wedge 160 is provided to force slips 156, 158, respectively, outwardly as the slips move downward relative to the wedge. Elastomeric packers 164 are confined about conduit 150 between upper wedge 160 and a lower wedge 166. The lower wedges coact with lower slips such as slips 170, 172 in a conventional manner to force the slips outwardly to engage the well casing.
A cylindrical sliding valve sleeve 174 is closely received within the lower end of conduit 150. The valve sleeve includes a pair of ports 176, 178, which, when the valve sleeve is in its uppermost condition as shown, are sealed off from a pair of ports 180, 182 formed in conduit 150. Valve sleeve 174 includes upwardly extending fingers such as fingers 184, 186. The fingers include upper portions 184a, 186a. Conduit 150 includes an annular groove 188 which receives the upper portions 184a, 186a of the fingers to maintain the valve in its upper position. Mandrel 130 includes an annular groove 190 formed about its radially outer surface. As will become apparent in the discussion of the operation of the packer and the setting tool, groove 190 is engagable with finger portions 184a, 186a in order to shift the valve between its upper closed position and its lower open position.
In operation, the string as shown in FIGS. 1A-1F is connected to conventional tubing string via threads 20 and is lowered into a well bore. Lug 26 is contained within upper portion 34 of J-slot 32 thus maintaining inner mandrel 22 in its upper position so that ports 28 are in alignment with annular space 44 to permit fluid communication between the inner mandrel (and hence the tubing string) and the well bore.
Setting tool 10 is in the configuration shown in FIGS. 1C and 1D. Locking ball 112 is urged into groove 140 on the mandrel by locking collar 114. The locking collar is restrained from vertical movement with respect to inner sleeve 80 by means of shear pin 116. Thus mandrel 130 is restrained, due to the ball received into groove 140, from vertical movement with respect to inner sleeve 80. Valve 174 remains in its closed position as shown in FIG. 1F while the string is lowered into the well.
While the string is lowered, circulating valve 16 permits filling of the string (including the tubing) with whatever fluids are present in the well bore. When the level at which it is desired to set packer 12 is reached, further lowering of the string is stopped. Prior to setting the packer, the circulating valve is closed to seal the interior of the string from the well bore. This is achieved by slight rotation and longitudinal movement of the drill string in order to move lug 26 from its position within upper portion 34 of the J-slot into lower portion 36. Drag block assembly 14 provides the necessary rotational and vertical drag to permit movement of lug 26 from its upper to its lower position. The tubing is now pressurized by pumping fluid into the tubing at the surface.
Such pressurization urges fluid in the string through bore 100 in mandrel 80 into hydraulic chamber 96. In a similar manner, fluid passes through bore 132 in the mandrel and through bore 102 in inner sleeve 80 into hydraulic chamber 98. The pressurization of hydraulic chambers 96, 98 causes upward movement of inner sleeve 80 due to the pressure applied to the lower sides of pistons 84, 86. Since mandrel 130 is locked to the inner sleeve as described above, the mandrel likewise moves upward. Upward movement of the inner sleeve pulls packer 12 upwardly via tension collar 144. Upward movement of conduit 150 results in the spreading of split ring 154 by contact with lower surface 78 of setting sleeve 62, causing upper slips 156, 158 to spread outwardly against the sides of the well bore due to the action of wedge 160. Continued upward movement of conduit 150 pulls lower slips 170, 172 over lower wedge 166, thus forcing lower slips 170, 172 outwardly into engagement with the sides of the well bore. Packer 12 is at this point set in the well bore.
Continued application of pressure in the tubing causes further upward movement of inner sleeve 80 until tension collar 144 breaks along narrowed portion 152. When the tension collar breaks, the inner sleeve is free to move upwardly until O-ring 120, riding on the top of locking collar 114, strikes lower surface 122 of piston 74. Thus, since the locking collar, the inner sleeve and the mandrel are locked together via the action of ball 112 in groove 140, each has moved upwardly by the same amount.
After O-ring 120 is compressed between locking collar 114 and piston 74, continued application of pressure in the tubing causes shearing of shear pin 116. When pin 116 shears, inner sleeve 80 continues further upward movement. Such additional upward movement of the inner sleeve permits ball 112 to be received within groove 118 on the locking collar. As soon as the ball is received within groove 118, spring 138 causes downward movement of mandrel 130 since the ball is no longer received within groove 140 of the mandrel. As mandrel 130 moves downwardly, groove 142 slides aqross slot 110. Groove 142 momentarily receives the ball to permit slot 110 and ball 112 to move above groove 118 as inner sleeve 80 continues upward movement. Upward movement of the inner sleeve continues until channel 128 is opposite lock ring 124. The conventional lock ring is biased inwardly and when channel 128 moves opposite the ring, the ring is partially received within channel 128 thus locking collar 114 to inner sleeve 80. The configuration of setting tool 10 is now as shown in FIG. 2.
In the configuration of FIG. 2, locking collar 114 is locked to inner sleeve 80 at a lower position than that at which shear pin 116 fixed the collar to the inner sleeve. Since conduit 150 has been moved upwardly while mandrel 130 has been permitted to move downwardly, the end of the mandrel is received within valve 174 and the valve is urged to its lowest position, thus aligning ports 176, 180 and ports 178, 182 to permit fluid flow from beneath the packer into the tubing (not shown). When the valve is so opened, groove 190 at the lower end of mandrel 130 receives upper portions 184a, 186a of the fingers (also not shown).
It should be noted that conduit 150 may be moved downward slightly through application of increased annulus pressure when mandrel 130 is inserted into packer 12, due to the seal between conduit 150 and mandrel 130. In a similar fashion, if valve 174 is not in its lower, open position, application of tubing pressure in excess of annulus pressure will move conduit 150 downwardly. As conduit 150 "floats" with respect to the upper and lower slips to a certain extent, this is not detrimental, as such action in a downward direction tends to set upper slips 156, 158 more firmly; pressure from below in the well bore will set lower slips 170, 172 more firmly (when valve 174 is closed).
If it is later desired to close the valve, the tubing string is lifted, thus lifting mandrel 130 and raising the valve to its upper closed position (as shown in the drawings). As the valve moves upwardly, the upper portions 184a, 186a of the fingers are received within groove 188 of conduit 150 and the mandrel continues upward movement thus leaving the valve locked in its closed position.
If thereafter, it is again desired to open the valve, the tubing string is lowered until surface 78 on outer sleeve 62 is set down on lock ring housing 159. When outer sleeve 62 is so positioned, mandrel 130 has engaged the upper portions 184a, 186a of the valve fingers in groove 190 and has moved the valve into its lower open position. It should be noted that due to the length of groove 142 on the mandrel, it is not possible for the weight of the tubing string to be applied through mandrel 130 to the bottom of the packer. Groove 142 permits a range of vertical travel, restricted by ball 112, of mandrel 130. When groove 142 is of sufficient length, the most force which can be applied through mandrel 130 to the bottom of the packer is the downward biasing force of spring 138, plus the tubing/annulus differential pressure times the differential area in the vicinity of O-ring 136.
It is to be appreciated that additions and modifications may be made to the instant embodiment of the invention without departing from the spirit thereof as defined in the following claims. | Apparatus for setting in a bore a well tool of the type having radially expandable anchor means and a mandrel-actuated slidable valve for permitting flow through the tool. Inner and outer sleeves are telescopically interengaged for suspension from a conduit string for lowering into a well bore. A shearable tension sleeve connects the tool to the lower end of the inner sleeve. A vertically shiftable mandrel having a longitudinal bore therethrough is received within the inner sleeve for engaging the well tool valve. A ball is received within a slot in the inner sleeve and is urged into a groove formed in the mandrel by a locking collar disposed about the inner sleeve. Annular pistons are provided between the inner and outer sleeves for moving the inner sleeve upwardly responsive to pressurization of the conduit string. Such upward movement shifts the mandrel downwardly with respect to the inner sleeve and shifts the locking collar to effect locking of the inner sleeve to the mandrel in its shifted position. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A COMPACT DISK APPENDIX
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The invention relates to a fabric used in papermaking. More specifically, the present invention relates to forming fabrics used in the forming section of a papermaking machine.
[0006] 2. Description of Background
[0007] In the art of papermaking, multiple steps occur from the introduction of a pulp slurry to the output of a finished paper product. The initial introduction of the slurry is at the portion of a papermaking machine known as the wet end. Here, the slurry, or fiber suspension, is initially dewatered when the slurry is introduced onto a moving forming fabric, in the forming section of the papermaking machine. Varying amounts of water is removed from the slurry through the forming fabric, resulting in the formation of a fibrous web on the surface of the forming fabric.
[0008] Forming fabrics address not only the dewatering of the slurry, but also the sheet formation, and therefore the sheet quality, resulting from the formation of the fibrous web. More specifically, the forming fabric must simultaneously control the rate of drainage while preventing fiber and other solid components contained in the slurry from passing through the fabric with the water. The role of the forming fabric also includes conveyance of the fibrous web to the press section of the papermaking machine.
[0009] Additionally, if the drainage occurs to rapidly or too slowly, the quality of the fibrous web is reduced, and overall machine production efficiency is reduced. Controlling drainage by way of fabric void volume is one of the fabric design criteria.
[0010] Forming fabrics have been produced to meet the needs and requirements of the various papermaking machines for the various paper grades being manufactured. As the needs arises to increase production speed of the papermaking machines and the quality of the paper being produced, the need for improved paper machine clothing allowing for increase production rates and improved quality resulted.
BRIEF SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention is for a fabric used in papermaking, and more particularly, as a forming fabric. In the preferred embodiment, the fabric is a hybrid warp exchange triple layer forming fabric. The fabric has a first weft system, a second weft system and a third weft system, the second weft system between the first and third weft systems. In the finished fabric, the second and third weft systems are preferably in the same plane. The fabric also has a plurality of warp systems, each warp system having at least one warp yarn. Each warp yarn binds with one of the first weft system, the third weft system, the first and second weft systems, and the second and third weft systems. A first warp system is an exchange warp system. Generally, machine direction (MD) yarns are warp yarns, and cross machine direction (CMD) yarns are weft yarns.
[0012] A weft system is a system of wefts that performs a function. As such, the first weft system can be a paper side weft, a wear side weft or and intermediate weft. In the preferred embodiment, the intermediate weft acts as a binding layer. Still further, the mesh density of the first weft system and the second weft system is independent from the mesh density of the third weft system and the second weft system.
[0013] Still further, the first weft system has a first yarn, the first yarn having a first diameter. Likewise, the second weft system has a second yarn, the second yarn having a second diameter, and the third weft system has a third yarn, the third yarn having a third diameter. The weft and warp yarn materials include, but are not limited to mono filament yarns, synthetic or polyester mono filament yarns, twisted mono filament yarns, twisted synthetic or twisted polyester or twisted polyarnide mono filament yarns, twisted multi-filament yarns, twisted synthetic or twisted polyester multi-filament yarns, and others. Various yarn profiles can be employed, including but not limited to yarns having a circular cross sectional shape with one or more diameters, or other cross sectional shapes, for example, non-round cross sectional shapes such as oval, or a polygonal cross sectional shapes, for example diamond, square, pentagonal, hexagonal, septagonal, octagonal, and so forth, or any other shape that the yarns may be fabricated.
[0014] Still further, each warp system can be independent. Each warp layer, has at least one warp yarn, and the at least one warp yarn has a fourth diameter.
[0015] Additionally, each warp system has a predetermined number of warp repeats, ranging from 2-112, preferably 2-28.
[0016] The triple layer forming fabric of the present invention has exchange warps that do not bind with larger diameter bottom wefts. Rather, they bind with a smaller diameter intermediate weft. All of the warp yarns can be the same diameter or there can be two different warp yarn diameters. In contrast, the warp yarns in the prior art fabrics must all be of the same diameter.
[0017] As a result, the exchange points can be spread out farther than the prior art, resulting in a less obvious pattern. This can be done because the bottom warps bind with the intermediate wefts between the exchanges.
[0018] The warp that weaves only on the bottom, or wear side of the fabric can be of a larger diameter than those that weave on the top, or paper side of the fabric. In this manner the modulus of the fabric is enhanced, and allows for larger diameter bottom wefts to be employed.
[0019] In another embodiment, the fabric has a first weft system, a second weft system and a third weft system, the second weft system between the first and third weft systems. The fabric also has a plurality of warp systems, each warp system having at least one warp yarn. Each warp yarn binds with one of the second weft system and one of the first and third weft systems.
[0020] It is also understood that there are no limitations to the paper grades or former types where this invention can be applied. It is also understood that the fabric can be woven utilizing either two or three warp beams.
[0021] These and other features and advantages of this invention are described in or are apparent from the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The preferred embodiments of the present inventions will be described in detail, with reference to the following figures, wherein:
[0023] FIGS. 1A-1B depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a two shed/three shed arrangement according to the present invention;
[0024] FIG. 2 depicts a forming side plan view of a triple layer fabric having a 2:1 warp ratio and a two/three shed arrangement according to the present invention;
[0025] FIGS. 3A-3B depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a three shed/three shed arrangement according to the present invention;
[0026] FIG. 4 depicts a forming side plan view of a triple layer fabric having a 2:1 warp ratio and a three/three shed arrangement according to the present invention;
[0027] FIGS. 5A-5C depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a two shed/four shed arrangement according to the present invention;
[0028] FIG. 6 depicts a forming side plan view of a triple layer fabric having a 2:1 warp ratio and a two shed/four shed arrangement according to the present invention;
[0029] FIGS. 7A-7C depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a two shed/six shed arrangement according to the present invention; and
[0030] FIG. 8 depicts a forming side plan view of a triple layer fabric having a 2:1 warp ratio and a two shed/six shed arrangement according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIGS. 1A-1B depict a cross-sectional view of a triple layer fabric 10 having a 2:1 warp ratio and a two shed/three shed arrangement according to the present invention, fabricated on a two beam loom. FIG. 2 depicts the forming side plan view of the same fabric 10 .
[0032] A first weft system 12 is shown above a second weft system 14 . The first and second weft systems 12 , 14 are shown above a third weft system 16 . Each weft system 12 , 14 , 16 is made up of a plurality of yarns 18 , 20 , 22 . First weft yarn 18 has a first yarn diameter, second weft yarn 20 has a second yarn diameter, and third weft yarn 22 has a third yarn diameter. The first, second and third yarn diameters 18 , 20 , 22 can be the same or different. Different size numerals for each of the different weft layer yarns 18 , 20 , 22 is indicative of a different weft yarn diameter in the preferred embodiment.
[0033] The first, second and third weft systems 12 , 14 , 16 are bound together by a plurality of warp systems 24 . FIGS. 1A-1B show fifteen warp systems 24 in a repeating pattern. Each warp system 24 has at least one warp yarn 26 , and each warp yarn 26 is woven in a two shed/three shed repetition.
[0034] The weft and warp yarn materials include, but are not limited to mono filament yarns, synthetic or polyester mono filament yarns, twisted mono filament yarns, twisted synthetic or twisted polyester or twisted polyarnide mono filament yarns, twisted multi-filament yarns, twisted synthetic or twisted polyester multi-filament yarns, and others. Various yarn profiles can be employed, including but not limited to yarns having a circular cross sectional shape with one or more diameters, or other cross sectional shapes, for example, non-round cross sectional shapes such as oval, or a polygonal cross sectional shapes, for example diamond, square, pentagonal, hexagonal, septagonal, octagonal, and so forth, or any other shape that the yarns may be fabricated into.
[0035] This first warp yarn 26 binds the top, or first weft 12 with the middle, or second weft 14 . A second warp yarn 30 also binds the top, or first weft 12 with the middle, or second weft 14 . The first and second warp yearns 26 , 30 form what is called an exchange warp. An exchange warp is, for example, when one member of a pair of warp yarns 26 , 30 is weaving with the first weft system 12 and the other member of the pair of warp yarns 26 , 30 is weaving with the second weft system 14 . Stated differently, an exchange warp allows for one warp yarn of a pair of warp yarns to weave in alternate fashion such that when the first warp yarn 26 is weaving with a first weft system 12 , the second warp yarn 30 is not weaving with the first weft system 12 , and both the first and the second warp yarns are not weaving the same weft at the same time.
[0036] In the present invention, while depicting a plurality of warp systems 24 , some yarns of the warp systems form exchange warp pairs and some of the warp systems do not form exchange warp pairs. In FIG. 1 , for example, the first warp yarn 26 and the second warp yarn 30 form the first warp system 28 , which is an exchange warp pair. In contrast, warp yarn 32 forms a second warp system 34 . Accordingly, warp yarn 32 does not cross the second warp yarn 30 of the first warp system 28 , and no exchange warp is formed.
[0037] FIG. 2 depicts the forming side plan view of the triple layer fabric 10 having a 2:1 warp ratio and a two shed/three shed arrangement according to the present invention. In this example, it can be readily seen that the first and second warp yarns 26 , 30 form a first warp system, and therefore a warp pair that forms an exchange warp. The x notation marks where the first warp yarn 26 appears in the forming side view forming a knuckle, and y indicates where the second warp yarn 30 appears in the forming side view forming a knuckle. The third warp yarn 32 , since it only binds the second weft system 14 with the third weft system 16 , does not appear in the forming side plan view. The boxes with forward slash fill denote where warps exchange, and boxes with grey fill denote locations of bottom side warp knuckles. Since the invention is directed to a triple layer fabric, the weave has a separate forming or paper side and a wear side.
[0038] This pattern repeats throughout the forming side plan view. For example, a fourth warp yarn 36 forms an exchange warp with a fifth warp yarn 38 . Similarly, a sixth warp yarn 40 forms a warp exchange with a seventh warp yarn 42 . An eighth warp yarn 44 does not form an exchange warp with another yarn. FIGS. 1A-1B further show a ninth warp yarn 46 , a tenth warp yarn 48 , and eleventh warp yarn 50 , a twelfth warp yarn 52 , and thirteenth warp yarn 54 , a fourteenth warp yarn 56 , and a fifteenth warp yarn 58 . Accordingly, FIG. 2 depicts fifteen warp repeats, with six pairs of exchanging warps and 3 bottom warps. The pattern repeats in both the forming side and the wear side layers. The double forward slashed areas in FIG. 2 show the crossover points of the warp exchange yarns below the forming side surface. The single grey areas in FIG. 2 show the warp yarn exposure on the wear side, that is, a wear side knuckle, not shown.
[0039] Accordingly, the views in FIGS. 1A-1B and 2 show one complete pattern in the machine direction.
[0040] FIGS. 3A-3B depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a three shed/three shed arrangement according to the present invention. FIG. 4 depicts the forming side plan view of the triple layer fabric having a 2:1 warp ratio and a three shed/three shed arrangement according to the present invention. As in FIGS. 1A-1B and 2 , the first warp yarn 26 forms an exchange warps with the second warp yarn 30 . The difference is that the first and second warp yarns 26 , 30 have a three shed weave pattern.
[0041] FIGS. 5A-5C depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a two shed/four shed arrangement according to the present invention, and FIG. 6 depicts the forming side plan view. Twenty-four warp yarns are shown as 118 , 120 , 122 , 124 , 126 , 128 , 130 , 132 , 134 , 136 , 138 , 140 , 142 , 144 , 148 , 150 , 152 , 154 , 156 , 158 , 160 , 162 and 164 . In this embodiment, an additional warp is added that only binds to the top, or first weft system 112 , and does not bind with the second or third weft systems 114 , 116 . These top binding only warps are designated 118 , 126 , 134 , 142 , 150 and 158 . The boxes in FIG. 6 with the reverse hash fill indicate locations where the bottom warp binds with the binding weft, or the second weft system.
[0042] FIGS. 7A-7C depict a cross-sectional view of a triple layer fabric having a 2:1 warp ratio and a two shed/six shed arrangement according to the present invention, and FIG. 8 depicts the forming side plan view. Twenty-four warp yarns are shown as 218 , 220 , 222 , 224 , 226 , 228 , 230 , 232 , 234 , 236 , 238 , 240 , 242 , 244 , 246 , 248 , 250 , 252 , 254 , 256 , 258 , 260 , 262 and 264 . In this embodiment, the fabric 10 is woven using a three beam configuration, and has a different weave pattern than that depicted in FIGS. 5-6 . This pattern shown in FIG. 8 has the additional notation of boxes containing horizontal or vertical fill lines, representing locations where an exchanging warp binds at the second weft layer according to the cross-sectional view of FIGS. 7A-7C .
[0043] The invention has been described that can be fabricated on a three beam loom. Likewise, the triple layer fabric of the present invention can also be fabricated on a four beam loom. Use of four beams could result in similar fabrics, with the addition of at least one of a top only warp, a bottom only warp, a bottom warp that binds at the second weft system, and a top pair that binds with the second weft system.
[0044] While the present invention has been particularly shown and described with reference to the foregoing preferred embodiments, those skilled in the art will understand that many variations may be made therein without departing from the spirit and scope of the invention as defined in the following claims. This description of the invention should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. The foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application. Where the claims recite “a” or “a first” element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. | A fabric for papermaking usable in the forming section of a paper making machine, having a first weft system, a second weft system and a third weft system; and a plurality of warp systems, each warp system having at least one warp yarn, each warp yarn binding with one of the first weft system, the third weft system, the first and second weft systems, and the second and third weft systems; wherein a first warp system is an exchange warp system. | 3 |
BACKGROUND OF INVENTION
1. Field of the Invention
This invention is directed to a valve utilized for hydraulically fracturing multiple zones in an oil and gas well without perforating the cement casing. A relatively new oil/gas well completion method involves the use of a valve that is installed as part of the casing string of the well and provides for cement flow within the casing when the valve element is in a closed position and allows for axial flow of fracturing fluid through the cement casing to fracture the formation near the valve. The invention disclosed herein is an improved valve used in this process.
2. Description of Related Art
Current designs for valves used in the completion method disclosed above are prone to failure because cement or other debris interferes with the opening of the valve after the cementing process has been completed. Portions of the sliding sleeve or pistons commonly used are exposed to either the flow of cement or the cement flowing between the well bore and the casing string.
BRIEF SUMMARY OF THE INVENTION
The valve according to the invention overcomes the difficulties described above by isolating a sliding sleeve between an outer housing and an inner mandrel. A rupture disk in the inner mandrel ruptures at a selected pressure. Pressure will then act against one end of the sliding sleeve and shift the sleeve to an open position so that fracturing fluid will be directed against the cement casing. The sliding sleeve includes a locking ring nut to prevent the sleeve from sliding back to a closing position.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS)
FIG. 1 is a side view of the valve according to one embodiment of the invention.
FIG. 2 is a cross sectional view of the valve in the closed position taken along line 2 - 2 of FIG. 1
FIG. 3 is a cross sectional view of the valve taken along line 3 - 3 of FIG. 2
FIG. 4 is a cross sectional view of the sliding sleeve
FIG. 5 is a cross sectional view of the locking ring holder
FIG. 6 is a cross sectional view of the locking ring
FIG. 7 is an end view of the locking ring
FIG. 8 is a cross sectional view of the valve in the open position
FIG. 9 is an enlarged view of the area circled in FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1 , an embodiment of valve 10 of the invention includes a main housing 13 and two similar end connector portions 11 , 12 .
Main housing 13 is a hollow cylindrical piece with threaded portions 61 at each end that receive threaded portions 18 of each end connector. End connectors 11 and 12 may be internally or externally threaded for connection to the casing string. As show in FIG. 2 , main housing 13 includes one or more openings 19 , which are surrounded by a circular protective cover 40 . Cover 40 is made of a high impact strength material.
Valve 10 includes a mandrel 30 which is formed as a hollow cylindrical tube extending between end connectors 11 , 12 as shown in FIG. 2 . Mandrel 30 includes one or more apertures 23 that extend through the outer wall of the mandrel. Mandrel 30 also has an exterior intermediate threaded portion 51 . One or more rupture disks 41 , 42 are located in the mandrel as shown in FIG. 3 . Rupture disks 41 , 42 are located within passageways that extend between the inner and outer surfaces of the mandrel 30 . Annular recesses 17 and 27 are provided in the outer surface of the mandrel for receiving suitable seals.
Mandrel 30 is confined between end connectors 11 and 12 by engaging a shoulder 15 in the interior surface of the end connectors. End connectors 11 and 12 include longitudinally extending portions 18 that space apart outer housing 13 and mandrel 30 thus forming a chamber 36 . Portions 18 have an annular recess 32 for relieving a suitable seal. A sliding sleeve member 20 is located within chamber 36 and is generally of a hollow cylindrical configuration as shown in FIG. 4 . The sliding sleeve member 20 includes a smaller diameter portion 24 that is threaded at 66 . Also it is provided with indentations 43 that receive the end portions of shear pins 21 . Sliding sleeve member 20 also includes annular grooves 16 and 22 that accommodate suitable annular seals.
A locking ring holder 25 has ratchet teeth 61 and holds locking ring 50 which has ratchet teeth 51 on its outer surface and ratchet teeth 55 on its inner surface shown in FIG. 9 . Locking ring 50 includes an opening at 91 as shown in FIG. 7 which allows it to grow in diameter as the sliding sleeve moves from the closed to open position.
Locking ring holder 25 has sufficient diameter clearance so that the locking ring can ratchet on the mandrel ratcheting teeth 63 yet never loose threaded contact with the lock ring holder. Locking ring holder 25 is threaded at 26 for engagement with threads 24 on the mandrel. Locking ring holder 25 also has a plurality of bores 46 and 62 for set screws, not shown.
In use, valve 10 may be connected to the casing string by end connectors 11 , 12 . One or more valves 10 may be incorporated into the casing string. After the casing string is deployed within the well, cement is pumped down through the casing and out the bottom into the annulus between the well bore and the casing as typical in the art. After the cement flow is terminated, a plug or other device is pumped down to wipe the casing and valve clean of residual cement. When the plug or other device has latched or sealed in the bottom hole assembly, pressure is increased to rupture the rupture disk at a predetermined pressure. The fluid pressure will act on sliding sleeve member 20 to cause the shear pins to break and then to move it downward or to the right as shown in FIG. 7 . This movement will allow fracing fluid to exit via opening 23 in the mandrel and openings 19 in the outer housing. The fracing fluid under pressure will remove protective cover 40 and crack the cement casing and also fracture the foundation adjacent to the valve 10 .
Due to the fact that the sliding sleeve member 20 is mostly isolated from the cement flow, the sleeve will have a lessor tendency to jam or require more pressure for actuation.
In the open position, locking ring 50 engages threads 63 on the mandrel to prevent the sleeve from moving back to the closed position.
A vent 37 is located in the outer housing 13 to allow air to exit when the valve is being assembled. The vent 37 is closed by a suitable plug after assembly.
Although the present invention has been described with respect to specific details, it is not intended that such details should be regarded as limitations on the scope of the invention, except to the extent that they are included in the accompanying claims. | A valve for use in fracing through cement casing in a well allows for flow of cement down the well during the cementing process and in the open position allows for fracing fluid to be directed through the cement casing for fracturing the formation adjacent the valve. The valve is constructed so as to reduce the likelihood of the valve to jam as a result of cement or other foreign material. | 4 |
SUMMARY OF THE INVENTION
The present invention is directed to a method of and a device for dividing a unit of cheese, such as a wheel or block of cheese, into individual pieces with the size and shape of the individual pieces being determined by the cutting edges on a mechanical dividing device.
Devices for dividing or cutting units of cheese are known. In the past longitudinal or transverse cutting devices have been used as well as devices for dividing round cheese blocks into sector-shaped parts.
In a known longitudinal and transverse cutting device, the cutting wires are tensioned in a frame and the cheese member is divided by pushing it through the cutting wires. A slotted stop interacts with a transverse cutting device equipped with several cutting wires and provided on the opposite side of a conveyor. The slots which align with the cutting wires permit the wires to pass freely through the cheese member, note German Auslegeschrift No. 18 16 008.
In another known device a round section of Roquefort cheese is cut into sector-shaped parts with the aid of steel cutting wires. The device has a round slide movable in the vertical direction for holding the cheese section with a guide and centering device arranged above it. The cutting device made up of a plurality of crossing cutting wires is supported above the guide device. The round cheese section is pressed through the cutting wires during the upward movement of the slide. The slide has diametrically extending, uniformly arranged grooves into which the wires move after completing the upward movement of the slide for separating the wires from the divided cheese pieces, note German Auslegeschrift No. 11 27 657.
Such dividing devices formed of cutting wires have the disadvantage that they can only be used for soft cheeses, such as Roquefort or processed cheese. Moreover, the use of these known cheese dividing devices is limited, because only exactly shaped cheese pieces of round or angular shaped cross-section can be cut. Such devices have been developed for use in cheese factories and particularly for the mass production of uniformly shaped cheese pieces suitable for a packing machine.
For universal use, such as for dividing large units of cheese, such as wheels or blocks of cheese, which often have hard rinds, at department store or supermarket counters, such known cheese dividing devices are not suitable.
When selling cheese, particularly in medium-hard or hard types, such as Gouda, Emmentaler and the like, it is important to maintain the supply of cheese in the undivided condition, since it stays fresh longer due to its protecting rind. In a store, whole units of cheese are usually divided manually. Cutting large and whole units of cheese is a difficult job, especially for the usual female sales personnel. In such cutting operations, hand injuries are not infrequent and injuries often occur which lead to lost time by employees generally due to excessive stress on the wrist and/or tendons in the hand.
Therefore, the primary object of the present invention is to provide a method of and a device for the mechanical division of units of cheese, such as wheels or blocks of cheese, particularly medium hard or hard cheese, where the unit of cheese can be subdivided into different shaped pieces and where the difficulties existing in the prior art are overcome.
In accordance with the present invention, the cutting or dividing device is compact, simple to operate and particularly accident-proof, especially for cutting cheeses enclosed within a hard rind. The device meets the stringent requirements regarding cleanliness and food hygiene and, further, needs little in the way of storage space. An important feature of the invention is the provision of the cutting inserts which can be quickly replaced in a problem-free manner so that the unit of cheese to be cut can be divided into different sized shapes. By means of the present invention, in a single operation a unit of cheese can be divided into a plurality of individual pieces to afford a salable assortment of different sizes and shapes.
In the method of the present invention the cheese is pressed upwardly through the cutting elements in a dividing device.
As a result, sales personnel are relieved of the heavy manual task of cutting the cheese and their time can be directed to the actual selling operation. Moreover, loss of personnel due to injuries or excessive stress on the hands and arms is avoided. In addition, the division of the unit of cheese into a salable assortment affords a positive sales promotion feature directed to the buying public.
In providing a salable assortment of pieces of cheese, a statistical division in size, shape and weight is afforded which best corresponds to the requirements of the purchasing public and, as a consequence, best meets the purchasing public's needs.
A feature of the method provides, after the dividing procedure, that the divided pieces of the unit of cheese are pushed along with their support beyond the cutting elements into a position where the pieces are accessible from all sides.
As a result, the removal of the cut pieces of cheese is facilitated advantageously. Moreover, the procedure of dividing the unit of cheese is visible to the purchasing public in an appealing manner and, consequently, stimulates purchasing interest.
To facilitate the cutting operation in very hard types of cheese, such as Emmentaler, which has a hard rind, the cutting elements are arranged to penetrate the cheese without causing any excessive stress. To afford such a cutting or dividing operation of a whole unit of cheese, the cheese, the cutting elements, or both, are sprayed with a liquid for assisting the cutting operation before commencing the cutting. Preferably, a water-spray mist is used.
A device for dividing a whole unit of cheese, such as a wheel or block of cheese, into individual pieces limited by the cutting edges in a mechanical dividing device, especially for carrying out the method of the invention, is characterized by arranging the cutting elements in the form of knife-like blades positioned within a rigid frame with at least certain of the blades disposed in parallel planes and extending perpendicular to the sides of the frame. The cheese is mounted on a support member divided into individual support parts each having a surface part on which the unit of cheese rests. Each surface part has a peripheral shape corresponding to the shape of one of the pieces of cheese, that is, the surface part has the shape, size and dimensions of one of the pieces of cheese being cut. The adjacent support parts are disposed in closely spaced relation so that interposed slots are located between them. The support parts are held in place by supporting elements extending upwardly from a base plate. Preferably, the base plate is disposed in parallel with the surface parts of the support member.
Accordingly, for the first time, the mechanical division of hard whole units of cheese enclosed by a rind, can be effected in an advantageous manner. With the support parts located on supporting elements it is possible to move the divided pieces of cheese into a position spaced from the cutting elements where the pieces are readily accessible. Furthermore, the arrangement of the support parts with the interposed slots has the advantage that the abrasion of the cheese such as into crumbs, does not take place in the slots as occurs in known cheese cutting devices. This feature facilitates the maintenance of the cleanliness of the device, and the indispensible requirement for cleanliness in the handling of foods can be met without difficulty.
Another characteristic of the device is the provision of a base with rigid, upstanding guide elements on which a vertically movable, horizontally arranged table is guided for mounting the cheese support and its base plate so that they are replaceable. At the upper ends of the guide elements, the frame for the cutting elements is positioned so that it can be quickly replaced. The base plate is inserted in the table using drawer-like slide-in units so that it can be easily and quickly replaced. Since the support and the cutting elements can be quickly replaced, it is possible to clean the various parts of the apparatus and to afford a problem-free changeover of the apparatus into different cutting arrangements for various types of cheese or shapes of the unit of cheese in an optimum manner.
To facilitate the simple and rapid replacement of the cutting elements, in an embodiment of the apparatus the the frame containing the cutting elements is provided with conically shaped bores for engagement with complementary conically shaped sections on the upper ends of the guide elements. The frame can be secured on the guide elements with fastening members such as wedges.
The various features of novelty which characterize the invention are pointed out 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 specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWING
In the drawing:
FIG. 1a is a plan view of a whole round unit or wheel of cheese divided into individual pieces in accordance with the present invention;
FIG. 1b is a plan view, similar to FIG. 1a where the unit of cheese is an elongated block divided into individual pieces in accordance with the present invention;
FIG. 2 is a plan view of a portion of the apparatus embodying the present invention illustrating a rigid frame supporting the cutting elements;
FIG. 3 is a plan view of the support divided into support parts each having a surface part and with slots located between adjacent support parts;
FIG. 4 is a sectional view taken along the line IV--IV in FIG. 3;
FIG. 5 is a side view, partly in section, of the complete apparatus of the present invention with the support shown in solid line in the lowered position and in broken line in the upper position with the unit of cheese divided into individual pieces; and
FIG. 6 is an embodiment of a cutting blade useful in the apparatus particularly for dividing hard types of cheese enclosed with a rind, and the blade is shown in an elevational view and in section, note the sectional line.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1a a whole unit of cheese 1, similar to a wheel of cheese, is divided into a multiplicity of individual pieces 2. The cutting lines 7 made in the unit of cheese 1 are arranged so that the unit is divided into two halves 3, 3', each forming approximately one-half of the original unit of cheese 1. Each of the halves 3, 3' includes a rectangularly shaped center piece 4, 4' separated from the remainder of the unit. The part of the unit of cheese 1 located outwardly from the center pieces 4, 4' is divided into sector-shaped pieces 6 by means of cutting lines or cutting elements which extend outwardly from the center pieces 4, 4' to the rind 8 enclosing the unit of cheese 1.
The division of the whole unit of cheese 1 illustrated in FIG. 1a results in 21 individual pieces 2 with the pieces having a different size, a different shape and a different weight. As a result, a salable assortment of individual pieces 2 is provided adapted to the maximum extent to the buying habits of customers, based on experience. If it is necessary to subdivide certain of the pieces 2 in effecting a sale, then the variety of shapes of the individual pieces permits a sales clerk to further subdivide a piece without any difficulty and without involving any time-consuming operations. An important consideration of the manner in which the individual pieces is formed is that each piece has at least two elongated and rectilinear cut edges. With such a shape, the purchaser is able to cut different large pieces at home or to process the piece of cheese 2 with a cheese cutter.
In FIG. 1b a different arrangement of cuts is shown in a more block-like unit of cheese 1' so that it is divided into a plurality of different individual pieces 2'. In this arrange- ment, it is also advantageous to separate the unit of cheese 1' into two halves 3, 3'. The unit of cheese 1' in FIG. 1b is different from the type of cheese shown in FIG. 1a and has a different shape as can be noted from the comparison of FIGS. 1a and 1b. In the embodiment exhibited in FIG. 1b, the cutting lines 7 are arranged essentially so that a greater number of angularly shaped individual pieces 2' are formed, certain of which are approximately square with the remainder having a long narrow configuration. One cutting line 7" extends obliquely relative to the long direction of the unit of cheese 1' so that a portion of the unit is cut into four obliquely-angled pieces 2".
The different arrangement of the cutting lines and the different shapes of the whole units of cheese 1, 1', and, in particular, the different types of cheese which can be cut, indicate a significant advantage of the method and the apparatus embodying the present invention. Accordingly, for the first time, a mechanical division or cutting of medium hard and hard whole units of cheese is possible in a retail store utilizing a mechanical dividing apparatus.
By means of the present invention the sales help is relieved from heavy physical work required in the manual cutting of whole units of cheese, with the result that the sales help can devote their time to the actual selling operation. Moreover, a customer can watch the mechanical division of the whole unit of cheese which is interesting and stimulates sales.
In FIG. 2 a plan view is provided of a dividing or cutting element 30. Element 30 includes a frame 9 supporting knife-blades 10 arranged to afford a network of cutting lines. Frame 9 is of a rigid construction, such as hollow box-shaped steel sections welded together. As viewed in FIG. 2, the frame 2 has a pair of longer sides and a pair of shorter sides. A fastening lug 11, 11' is attached to the center point of each of the shorter sides. The fastening lugs are secured to the frame by welds and each lug has a conically shaped recess 12, 12' in the shape of a conically shaped receiving bore. The blades 10 form, according to the type of cheese to be cut, two central rectangles 13, 13'. The cutting blades 14 extend perpendicularly to and outwardly from the rectangles 13, 13', while the blades 15, 15' extend outwardly at oblique angles relative to the sides of the rectangles. Between the sides of the rectangles and the longer sides of the frame 9, blades 15' are provided parallel to the long sides or to the longer axis of the frame. Blades 10', 14, 15, 15' and 15" are connected with one another at a metallic joint 16. Preferably the connection is made in a hard-soldering process, such as a protective gas-hard-soldering process. Accordingly, the connection between the individual blades corresponds approximately to that of the steel forming the blades. This interconnection of the blades for forming the cutting element 30 affords the necessary strength in the overall cutting element necessary for separating a whole unit of cheese 1, 1' enclosed within a hard rind.
In FIGS. 3 and 4 a support member 17 is shown shaped complementary to the cutting element illustrated in FIG. 2. FIG. 3 provides a plan view, while FIG. 4 affords a side view, partly in section, along the line IV--IV in FIG. 3. A support element for the unit of cheese is made up of a number of individual support parts 18 secured to the upper ends of supporting members 19 which are secured at their lower ends to a base plate 20. The base plate 20 is of such a rigid construction that it withstands the forces acting on it during the cutting process without experiencing any apparent bending action. The base plate 20 is a steel plate of adequate stability. It is also possible to form the base plate 20 of fiber reinforced plastics and, in such an embodiment, preferably it is strongly ribbed at its underside to afford stability. Furthermore, the base plate 20 may be constructed as a sandwich member. Regardless of its particular construction, the base plate must be extremely strong as well as relatively light. The supporting members 19 are thin-walled steel tubes and are attached by welding to the base plate 20 and to the individual support parts 18. Alternatively, the base plate, the supporting members, and the support parts may be formed of plastics or plexiglass.
In FIG. 4 the surface parts of the support parts 18 are covered with a coating 21, such as of Teflon. Such a construction is advantageous for food hygiene requirements. As can be noted in FIG. 3, slots 33 are formed between the individual support parts 18 so that the blades 10 of the cutting elements 30, note FIG. 2, can pass through the support element during the cutting or dividing operation.
In FIG. 5 a complete dividing apparatus 22 is illustrated in side view, partly in section. The apparatus has a heavy base plate 23 forming the base structure for the apparatus and threaded bushings 24 are welded to the base plate. Guide members in the form of guide rods 25, 25' are screwed into the bushings 24 so that the guide rods extend upwardly, generally vertically from the base plate 23. A horizontal support table 26 is mounted on the guide rods 25, 25' by means of guide bushings 27, 27' and the table 26 is supported by a hydraulic piston-cylinder unit 32. The hydraulic piston-cylinder unit 32 is shown in the collapsed state and it is arranged to provide a long working stroke H. The guide bushings 27, 27' and the support table 26 have slide-in guides 28, 28' into which the base plate 20 of the support member 17 can be replaceably inserted. With such an arrangement there is the advantage that the support member can be easily replaced when necessary.
The upper ends 29, 29' of the guide elements or guide rods 25, 25' are frusto-conically shaped to afford a quick fastening or release of the cutting element 30. Slots 34, 34' are formed in the guide rods so that a wedge connection can be made between the rods and the cutting element. With this construction an absolutely safe and uncomplicated placement and centering of the cutting elements on the rods can be effected. In such placement, the frame 9 is supported on the upper ends of the guide rods 25, 25' with the ends 29, 29' seated within the conically shaped bores 12 in the fastening lugs 11. Due to the slots 34, 34' arranged to receive wedge connectors, a secure attachment is provided between the frame 9 and the guide rods 25, 25' in a simple manner and in a matter of seconds.
As viewed in FIG. 5, the horizontal support table 26 is shown in full lines in the lower position and a whole unit of cheese 1, shown in dashed lines, is positioned on the surface parts of the support parts 18. Centering of the unit of cheese on the support member is not required nor desired due to the intended uneven division of the cheese into a plurality of differently shaped pieces. To facilitate the positioning of the unit of cheese on the support element, it may be provided with color identification in the form of circles or ellipses, not shown, in the manner of a target, for locating the cheese in place. The upper position of the support member 17, shown in broken line, illustrates the unit of cheese 1 after it has been pressed from the bottom upwardly through the cutting element 30 so that it is divided in a manner such as is shown in FIGS. 1a and 1b. As can be seen in FIG. 5, the upper portion of the support member 17 projects upwardly above the upper plane of the cutting element 30 so that the divided cheese pieces 2 are freely accessible from all sides of the apparatus. This feature considerably facilitates the operation and use of the apparatus.
FIGS. 5 and 6 show two different embodiments of a cutting blade 10, 10' which can be used in the apparatus.
In FIG. 5, the downwardly directed cutting edge 35 of the blade 10 has an arrowhead-like shape with the centerpoint on the blade leading in the cutting direction. The cutting edge of the blade is formed with a plurality of pointed teeth 36. Unlike a saw-tooth blade, the teeth 36 are not dihedral. The teeth 36 are arc-shaped with converging tooth flanks and are similar to shark teeth.
In FIG. 6, the blade 10' has a concavely shaped cutting edge 35'. The cutting edge, as is shown in section, is triangularly shaped and, due to its concave configuration, unlike the blade in FIG. 5 where the centerpoint of the blade leads in the cutting direction, in FIG. 6 the opposite ends of the cutting blade lead the remainder of the cutting edge in the cutting or dividing operation.
With the special shape of the blades 10, 10', as distinguished from rectilinear cutting edges, initially the cutting pressure is concentrated in one or several locations so that, in a surprising manner, for the first time with the present invention it is possible to cut and separate the rinds on hard types of cheese.
It has been found that the cutting forces needed to divide a hard cheese, are applied to the cutting elements as shown in FIGS. 5 and 6 so that only a fraction of the forces are needed as compared to the forces required when a smooth rectilinear cutting edge is employed.
As shown in FIG. 5, the apparatus 22 is compact as well as simple. Therefore, it is well suited for problem-free use in a retail store and fulfills, in an ideal manner, the task for which the present invention is intended.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles. | To divide a unit of cheese, such as a wheel or block of cheese, into individual pieces of different sizes and shapes, the unit of cheese is placed on a support surface and is moved relative to a cutting device. The cutting device is made up of a network of knife-like blades each with a cutting edge and the blades are arranged to divide the unit of cheese into the desired shaped pieces. The entire unit of cheese is cut up into the individual pieces in a single cutting operation. In the cutting operation, the unit of cheese is placed on a support part movable relative to the cutting device. The support part is subdivided into surface parts each having a shape corresponding to the shape of one of the individual pieces of cheese. the support part is movably mounted on upwardly extending guide elements. The cutting device is held in a stationary position on the guide elements. The support part and the cutting device are replaceably mounted on the guide elements. | 8 |
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The present invention refers to a continuous freeze drying apparatus that can be employed in a particularly advantageous way when the treatment of great amounts of the same product is required.
2. BACKGROUND INFORMATION
As well known, freeze drying or lyophilization is a physical treatment to which perishable organic substances are subjected in order to ensure their long preservation.
It consists of a drying or dehydration process carried out under low temperature and vacuum conditions, where a diluent, usually water, is removed from the desired product through direct evaporation from the solid state (drying by sublimation).
U.S. Pat. No. 4,590,684 in the name of EDEN RESEARCH LABORATORIES, INC. describes a continuous freeze drying apparatus containing an inlet and a passageway for slurry material, an underlying holed plate including cooling passageways whose double function is cooling the plate and freezing the slurry passing through it, and a sublimation passageway that crosses the plate on the opposite surface to the inlet side.
A reduced pressure is kept inside the sublimation passageway and the pressure drop is kept within the plate area containing the slurry.
Next to the above-mentioned plate, in the sublimation passageway, a heating element checks the movement of the slurry cooled through the passageway increasing its sublimation upon entry.
This apparatus, however, has the disadvantage of providing a freeze dried product that is dimensionally dishomogeneous and morphologically uncontrolled, further requiring a subsequent intervention to make it powdery or granulated.
U.S. Pat. No. 3,740,860 in the name of SMITHERM INDUSTRIES, INC. describes a continuous freeze drying apparatus where a product is freezed onto a conveyor in a freezing compartment inside a vacuum vessel in which the pressure is high enough to keep volatiles from evolving from the freeze dried product.
This apparatus is provided for a continuous supply with a good amount, thus generating a compact output material and not a granulated one that can be more easily controlled and treated.
SUMMARY OF THE INVENTION
Purpose of the present invention is eliminating or reducing the above inconveniences or disadvantages, providing a continuous freeze drying apparatus suitable to automatically provide for a high production of the desired freeze dried powder, and at the same time to enable a continuous control of the powdery granule size; and suitable to avoid mechanical actions on the freeze dried product that could impair its morphological integrity, and to avoid, particularly for pharmaceutical freeze dried products, human interventions that could generate possible contaminations.
These and other purposes and advantages of the invention, as will appear from the following description, are obtained with a continous freeze drying apparatus comtaining:
a sealed vessel, said vessel comprising walls;
a controlled-pressure chamber contained inside said sealed vessel;
two condensation elements, each one of said two condensation elements being connected to said sealed vessel at a corresponding one of said walls;
a vacuum pump connected to said two condensation elements;
two check valves connected to said two condensation elements, each one of said two check valves being interposed between said vessel and said two condensation elements;
wherein said controlled-pressure chamber includes:
a revolving cylinder refrigerated at controlled temperature, said revolving cylinder having a lateral surface;
a scraping means, slightly spaced from said revolving cylinder and placed orthogonally to said lateral surface of said revolving cylinder;
a nebulizing means to spray a product to be freeze dried onto said lateral surface of said revolving cylinder, from which a freezed product is removed by said scraping means;
a plurality of overlapped revolving planes to collect and distribute a freezed material, each one of said plurality of revolving planes having a plurality of holes or gauged notches to make particles of a size less then the diameter of said holes or said notches, pass through them;
a plurality of heating elements interposed between each one of said revolving planes for the sublimation of a material to be freeze dried;
and wherein said continuous freeze drying apparatus further comprises a flow-regulating means and a removable means to collect a freeze dried material, both said flow-regulation means ans said removable means being located below one of the walls of said sealed vessel.
Further properties and advantages of the invention will better appear from the description of a preferred, but not exclusive, embodiment of the apparatus shown as a not limiting example in the enclosed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of the continuous freeze drying apparatus according to the present invention;
FIG. 2 is a side view of the continuous freeze drying apparatus according to the present invention;
FIG. 3 is a plan view of a revolving plane according to an embodiment of the invention; and
FIG. 4 is a plan view of a revolving plane according to another embodiment of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1 and 2, the continuous freeze drying apparatus is composed of a sealed vessel 10 having an internal chamber 11, with a laterally-hinged access door, not shown in the Figures to have clearer drawings, substantially parallelepiped-shaped, connected, at corresponding lateral surfaces or walls 13, 13', to the ducts 12, 12' respectively supporting two chuck valves 14, 14' that intercept the thermal flow coming from the above-said chamber 11, and to two elements 16, 16' condensing the subliming solvent from the freezed product to be freeze dried, connected to a vacuum pump 18 through the ducts 20 and 20'.
Chamber 11 houses a revolving cylinder 22 keyed to a hollow shaft 24 (to make a cooling fluid pass through it) passing through the lateral surface 13.
A pinion, that is engaged to a chain 26 operated by an electric motor 28, is keyed to one end of said hollow shaft 24.
A nebulizing means 30 for the material to be freeze dried is placed next to said revolving cylinder 22 at a position that is substantially orthogonal with respect to an horizontal rotation axis and above the lateral surface, so that the nebulized material settles onto said lateral surface and is cooled when contacting it. A vessel 32 supplies the above-mentioned nebulizer 30 with material to be freeze dried through a connecting duct 34.
The removal of the material to be freeze dried, now freezed by the surface of the revolving cylinder 22, is carried out by a scraping means 35 that, grazing the freezed material, removes it and make it fall onto the underlying revolving planes.
The scraping means 36 is composed of a plan blade 38 with two tongues 40 (FIG. 2) placed at its side ends in order to convey the removed material towards the underlying planes.
On its upper side, said blade 38 is secured to an horizontal pin 42 (FIG. 1) protruding from the chamber 11 through its wall 13; this pin 42 has, at one of its ends, an operating lever 44 to move it to an angular position defined by the blade itself.
The material freezed on the revolving cylinder 22 and removed by the scraping blade 38, is collected onto a first revolving plane 46 and is afterwards distributed to other revolving planes 48, 50, 52, 54, 56 located one after the other below said first plane.
Each revolving plane 46÷56 shows a circular edge 58 (FIGS. 3 and 4) containing the material that can be freeze dried and a plurality of gauged holes 60 (FIG. 4) radially placed on the base of the plane itself, or a plurality of gauged through-notches 62, as shown in FIG. 3.
The revolving planes 46 +56 are centrally secured to a revolving shaft 64 rotatingly operated by an electric motor 66.
Both the gauged holes 60 and the gauged notches 62 present in the revolving planes 46÷56 carry out, at their slight impact with the freezed crystals of the material that can be freeze dried, a well-defined dimensional selection without subjecting them to such heavy mechanical actions as to impair the morphological structure of the material itself.
A plurality of heating elements, generally shown as 68, like armored resistors or serpentine ducts for thermal carrier fluids or radiating plate or lamp elements, are placed between the different revolving planes 46÷56 in order to heat the freeze dried material, subliming it.
The particular arrangement of the heating elements 68 provided inside the chamber 11, advantageously solves the problem of a quick sublimation of the treated material, greatly reducing working times and at the same time increasing production; in fact, on the same revolving plane, for example the one shown as 52 in FIG. 1, two heating elements shown as 68' and 68" in FIG. 1 simultaneously operate, the first one, by convection, heating the area located above the revolving plane and the second one, by conduction, heating the base of the revolving plane.
With the above-described arrangement, a further drying step, known to the experts in the field as "secondary drying", has been advantageously removed, thus reducing production costs.
The freeze dried material that, falling from the revolving plane 56, settles onto the lower wall 70 of the vessel 10, is collected into a removable vessel 72 connected to a valve 74 that adjusts the amount of flow for the freeze dried material.
A preferred embodiment of the invention has been described, but obviously it is prone to numerous modifications or variations, like for example the number of heating elements and/or of revolving planes, always remaining within the scope of the inventive idea. | Continuous freeze drying apparatus composed of a vessel whose internal chamber houses a cooled revolving cylinder on which a nebulizer sprays the material to be freeze dried.
A scraping blade, grazing the freezed material, removes it making it fall onto revolving holed planes heated by heating elements interposed between these revolving planes, in order to obtain a quick sublimation of the substance to be freeze dried. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to automatic door and gate systems, and more particularly to automatic door safety systems which detect hazardous conditions, obstructions and adjusts operating controls accordingly.
2. Related Art
Systems which control gates and motorized doors have been well-developed in commercial and residential applications. Systems which control doors and gates typically comprise a motorized system which opens and closes the gate or the door upon command such as when a switch is activated or a motion detector senses the arrival of a vehicle in a predetermined area. Such systems often include additional devices and apparatus which assist in the utility or safety of the systems so disposed.
The ubiquitous form of automatic door systems as for home garages or warehouse entry and exit doors or large overhead doors for commercial buildings usually have a transmitter and receiver allowing the doors to be opened remotely when approaching the door. Other systems may have sensors such as proximity sensors, light beams, pressure sensors or the like that automatically close or open doors for safety reasons or for convenience.
Existing systems have had safety means to provide that the gate being operated or the door being closed react should there be a person or other obstruction in the path of the moving gate or door. If a person or a car moves into a moving garage door's path as the door is being closed, the system should sense this condition, thereby allowing the door to stop or reverse itself preventing damage or injury.
Many of the existing systems use some type of device which monitors the visual path across the threshold to be protected such as may be the case with light beams which are used to allow continuous monitoring of a desired path. It would be appreciated that a continuous light beam would be obstructed, even momentarily, by a person walking through the beam or a vehicle blocking the complete path of the light beam. Many photoelectric systems such as described use either visible light or more commonly infrared light to monitor the obstruction path to be protected.
In many instances it is inconvenient or impractical to use wired control or power supply lines between a detector and the photo emitter to supply power or otherwise integrate the system components. Wired systems or electromechanical connections are frequently subject to potential failures from component fatigue induced by physical stress. Safety devices which are put in place to prevent possible injury or damage should always be operating properly to identify such problems and to take the appropriate actions such as to reverse a motor or to stop the action of a control system. If a hazard or obstruction warning or sensing device is not functioning properly, a door or gate may continue to close regardless of whether the obstruction is encountered potentially causing damage or injury and must be avoided with present day safety requirements as they are. Since many systems use hard wired control systems to connect the sensors, part of the system vulnerability is the breaking of wires or the inadvertent disconnection of the control wiring during operation of the equipment or otherwise.
There are also wireless devices now available and deployed which provide for control information to be transmitted or received without direct connection by a hard wired device. Short range wireless systems require batteries. When a battery system is deployed in such a safety device, it is desirable to have as much warning as possible that the battery device being deployed has been depleted so that the system battery can be renewed prior to complete failure of the system. Systems deployed today utilizing batteries could fail if the battery is being depleted to transmit a low battery condition in a wireless control scenario. It would be desirable to deploy wireless obstruction sensing control systems that would be able to provide a long term, low battery condition indication without causing the battery drain from the signaling of the low battery condition to add to the already depleted battery.
SUMMARY OF THE INVENTION
The present invention provides an automatic door control system for operating a gate or a door which detects and causes the door to react to obstructions or other hazardous conditions which block a control beam. The invention is comprised of a battery operated wireless infrared light emitter, an infrared light receiver and a control system means integrated into the receiver with one or more of the transmitter or receiver components all disposed to operate in a wireless environment. The wireless transmitter unit utilizes batteries for power and can sense obstructions a distance of thirty feet from the transmitter to the receiver.
A low battery indication is provided wirelessly from the transmitter utilizing a signaling protocol to provide warnings of a low battery condition before the transmitter battery power source has been depleted. Signaling of a low battery condition is continuous to enhance the safety of the device and provisions are provided to change the operating condition of the transmitter such as to be as little a drain on the battery as practical during a low battery condition so that power remains available for as long, as possible in the low battery condition sensing control state.
A photoelectric safety sensor applying wireless connections for use with an automatic door control system has an infrared transmitter, an infrared receiver and control means all of which act in detecting obstructions blocking the operation of a motorized door or gate. The system detects disruption between the infrared transmitter and receiver, thereby detecting interfering objects in the path of the moving door or gate being protected.
The system disclosed includes a controller integrated with an infrared receiver and a wireless transmitter which easily mounts to a specified height above the floor or grade level to provide protection to the threshold as desired. The invention is based on through-beam technology. When the infrared beam is blocked by an obstruction, the receiver sends a signal to the operator control system to stop and reverse the motion of the door or gate being protected.
The system's safety is enhanced through the use of a low battery signaling means integrated in the infrared transmitter to allow for the placement of the transmitter into a lower power consumption state at the same time signaling a low battery condition. The invention provides for extended operation of a wireless transmitter to provide for an extended period of time under which the transmitter can operate in a low battery condition by changing the signaling information data rate to reduce transmitter power consumption. The difference in signaling data rate also is used as the indicator for the signaling of low battery condition. An improvement of the invention is comprised of a change of signaling state in the transmitter from a first state to a second state depending on battery voltage. A first state has a higher repetition rate and duty cycle indicating good battery voltage. A second state of the transmitter increases the time between group pulse periods, reducing duty cycle and otherwise providing a positive indication of the change of state from the first condition to a second condition, all depending on battery voltage.
A transmitter unit incorporated in the present invention is a battery operated wireless infrared emitter with low battery indication provided over the wireless communications means while being useful for sensing obstruction over a distance of thirty (30) feet while maintaining a minimum battery life of one year. Infrared controller/receiver means includes a microprocessor-based externally powered system which detects the infrared pulses from the transmitter emitter unit and controls the operation of the motorized door or gate. When the system detects an obstruction in receiving the infrared light, the receiver controller sends a control signal to the operation means to stop and open the door gate. The receiver/controller also includes a low battery indicator buzzer which is activated when the transmitter emitter signals a low battery condition.
The benefits of the invention include the lack of control wires to install the infrared transmitter or emitter means which reduces installation time while providing for low battery maintenance because of extended battery life incorporated into the design of the unit. The unit features beam alignment indicators to help a user install the transmitter and receiver unit and locate an optimal sighting line for defining the unobstructed path to be used for the infrared beam.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic system overview showing system components in an embodiment of the invention utilized to protect a motorized door.
FIG. 2 is a block diagram of the transmitter portion of the wireless photo eye system.
FIG. 3 is a diagram of the receiver and controller portion of the wireless photo eye system.
FIG. 4 is a timing diagram illustrating the wireless photo eye transmitter pulse repetition rate and the differences in the timing given the condition of the batteries.
FIG. 5 is a block diagram illustrating the software function of the wireless photo eye transmitter.
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described with reference to the various figures wherein like numbers refer to like parts. FIG. 1 is a schematic representation of the invention showing an application as a safety system for a typical motorized overhead garage door opener. A typical system in which the preferred embodiment of the invention is applied includes a movable overhead door 16 which moves vertically riding on door tracks 22 . Typically motor 18 is operatively connected to door 16 providing motion to open and close door 16 upon command. Typically in motor 18 , a controller 20 is either integrated into the motor control systems found in present day electric motors or is contained separately in a remotely located control system attached, for example, on a wall or near a manual activator button such as to command opening and closing door 16 .
In the present invention it is desired to monitor obstructions in the path of door 16 utilizing an infrared (“IR”) beam 14 . Infrared beam 14 originates from transmitter 10 sending a directional infrared light beam to receiver 12 . It will be appreciated by those skilled in the art of garage door technology that light beams, whether visible light or infrared wavelength light should be continuously generated such as to be in operation to verify the unobstructed path of beam 14 if door 16 is commanded to move, particularly in the downward direction.
The present invention provides for a unique system to allow transmitter 10 to be wireless and fully battery operated while allowing a long battery lifetime. It will be appreciated that transmitter 10 , while being wireless, would still need to be transmitting infrared beam 14 on a continuous basis in order to be assured that any obstruction in the path of door 16 would be sensed in a timely fashion. In a wired environment where power conservation is not an important consideration, it would be desirable to allow transmitter 10 to transmit continuously rather than command transmitter 10 into an on or off mode depending on the operation of door 16 . IR beam photoelectric receiver 12 runs continuously as being hard-wired to a power source and to controller 20 which communicates with receiver 12 as depicted in the example in FIG. 1 .
Because an objective of the invention is to allow extended battery life in transmitter 10 without cycling the transmitter between an on, off or dormant state, a control system is necessary to allow for extended battery life of the transmitter and to further provide for positive signaling of a low battery condition to enhance safety.
Turning to FIG. 2 , a block diagram of the system which controls infrared wireless transmitter 10 is shown. Wireless transmitter system 30 is comprised of power supply means 32 , microcontroller means 34 , low battery detection means 36 and current driving means 38 .
Transmitter system 30 is contained within transmitter 10 . Transmitter 10 is stationary and mounted at a specific height above floor or grade level opposite side of the area to be protected between transmitter 10 and receiver 12 . In a preferred embodiment, transmitter 10 emits an infrared beam of a wavelength of 940 nm. A different infrared wavelength may be employed with good results if desired. Transmitter 10 and receiver 12 can be aligned when being placed into service by having a locally installed LED or some other indicator which describes continuity when IR beam 14 is in place between the correct sensors in transmitter 10 and receiver 12 .
Receiver 12 is comprised of receiver system 40 as shown in FIG. 3 . System 40 is comprised of power supply means 42 , microcontroller means 44 , relay activation means 46 , a buzzer or other indicator means 48 and photo detection means 50 .
Transmitter 10 uses microcontroller means 34 to generate infrared bursts of eight (8) pulses with time differences of either 12.3 milliseconds or 14.3 milliseconds between the groups of bursts 62 as shown in FIG. 4 . Infrared light that defines beam 14 is generated by an infrared LED which does not produce a continuous light beam, but rather provides said burst of 8 infrared pulses in a group in order to minimize battery consumption while having sufficient duty cycle to essentially provide continuous obstruction coverage of the path defined by beam 14 . In a preferred embodiment, the time difference between the bursts is generated by transmitter 10 depending on transmitter system 30 within transmitter 10 depending on the battery voltage providing power to transmitter system 30 within transmitter 10 . If the battery in transmitter 10 is above a defined threshold voltage, the time difference between said pulse groups of eight (8) pulses is 12.3 milliseconds. When the battery voltage within transmitter 10 is below a defined threshold voltage, the time delay between pulse groups 62 is 14.3 milliseconds.
Transmitter system 30 uses two system frequencies. A frequency of 125 KHz and 4 MHz. A frequency of 4 MHz is used for generating the pulse. The remainder of microcontroller means 34 runs on a clock frequency of 125 KHz. By running the microcontroller means 34 at the lower frequency, the total current consumption of microcontroller means 34 is reduced and therefore the internal battery will last longer.
One advantage of the invention is realized by decreasing the battery duty cycle in transmitter 10 when the voltage driving transmitter 10 is below a threshold voltage. As demonstrated graphically in FIG. 4 , the transmitter pulse repetition groups diagram for a good battery condition shown at diagram 60 illustrates that individual pulses 66 are transmitted as a pulse group 62 , which is defined a total group duration of 210 μs (microseconds). Pulse group 62 is repeated again after a pulse group delay period of 12.3 milliseconds shown at 64 .
Low battery pulse diagram 70 shown in FIG. 4 uses the same pulses and pulse group design with the exception of a group pulse group timing delay changed to 14.3 milliseconds at 72 when said threshold voltage of the battery in transmitter 10 falls below the design value. Such a favorable change in power duty cycle when the battery is already below the threshold voltage helps to increase the battery life of the system in a low voltage condition thereby allowing longer lasting low battery signaling before transmitter 10 fails to operate from a battery reaching the end of its useful life.
As shown in FIG. 3 , system 40 contains a buzzer activation means which provides signaling when transmitter 10 (shown in FIG. 1 ) is in the low battery mode. When transmitter 10 has a low battery voltage, it extends the period between pulse groups 62 as shown in FIG. 4 . In such a manner, the buzzer means 48 activates. If desired, microcontroller means 44 in receiver system 40 can lock out operation of controller 20 thereby preventing operation of door 16 until the battery in transmitter 10 is replaced. In a wireless environment, it is important to extend the operational time of the system monitoring the obstruction path for as long as possible so that an operator or system maintenance person is alerted that the battery in transmitter 10 should be changed prior to the time that the battery fails entirely. Allowing a low voltage condition in transmitter 10 to be signaled a long period of time assures that the low voltage condition will be noticed and corrected if even if it occurs at a time when any warning by buzzer activation means 48 would go unheeded for several days if there are no human operators immediately available to take notice of the alarm condition.
FIG. 5 demonstrates the operation of the control software which can be effectively used to carry out the objectives of the present invention. A block diagram of control code system 80 depicted in FIG. 5 demonstrates the flow of the firmware used in the present invention. At system start 82 , control code system 80 initializes peripherals, interrupts and sets the clock frequency to 125 KHz at 84 . The system then determines whether the battery of transmitter 10 is low at 86 . If transmitter 10 's battery is not low, a selection is made to load a timer with the appropriate value at 90 . If transmitter 10 's battery is low, the system will decide to load the timer with an appropriate value 88 . It can be appreciated that the selection of the appropriate values at timer 90 is shown in pulse diagram 60 . The appropriate value at a low battery 88 is depicted in low battery pulse diagram 70 in FIG. 4 . The selection of the path to load the correct timer is a function of battery voltage.
Returning to FIG. 5 , regardless of whether there is a high or low battery condition, transmitter control code system 80 then sets a clock frequency to 4 MHz at 92 . The system then generates 8 pulses in a frequency range of 35 to 40 KHz (depending on design discretion in the application) at 94 and thereafter selects a clock frequency of 125 KHz at 96 . A start timer is then activated at 98 and a decision is made at 100 as to whether the timer has expired at logic branch 100 to hold a condition of control code system 80 in a loop 102 if the timer has not expired but thereafter cycling back to the input of low battery condition monitoring 86 through path 104 as described.
System clock used in the wireless transmitter system 30 is programmable. The code applied uses two types of internal clocks as described above. The first clock uses a clock rate of 125 KHz and the second clock uses a rate of 4 MHz. The 125 KHz is the slowest stable clock and is used during program initialization and also to run the two timers described of 12.3 milliseconds and 14.3 milliseconds. Power consumption of the invention is reduced by using a slower clock speed for most of the program execution described graphically in FIG. 5 . Four (4) MHz clock speed is used for generating eight (8) pulses in a frequency range of 35 to 40 KHz.
Although the invention has been described in accordance with the preferred embodiment and a useful alternative embodiment, it will be appreciated by those skilled in the art that the application of the present invention is useful in a variety of configurations and designs not specifically described above. All such designs and applications are considered to be within the scope of the present disclosure, and the invention is applicable across a wide variety of applications. Such applications are considered within the scope and spirit of the present invention. | A wireless, automatic door obstruction detection system for protecting a motorized door or gate by signaling various hazardous conditions and reacting to said conditions by signaling control means. The invention utilizes wireless infrared emitter, receiver and controller apparatus. Infrared pulse timing data is sent as pulse repetition rate changes depending upon battery condition. In a preferred embodiment of the invention, the photoelectric transmitter emits timed pulse groups to present control information differentiating between a good battery and a low battery condition in the wireless transmitter. A wireless photoelectric transmitter extends the time period between pulse groups to indicate a low battery condition. A low battery condition signaling thereby presents a low power drain condition allowing for an extended period of low battery condition signaling. | 4 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to a symbol timing recovery method and apparatus in a television receiver. More specifically, the present invention relates to a symbol timing recovery method apparatus useful in a high definition digital television receiver.
[0003] 2. Discussion of the Related Art
[0004] Any terrestrial digital TV system must perform a number of functions, and overcome a number of problems, in transmitting signals to a receiver. For example, the United States has adopted the Advanced Television System Committee (ATSC) System using eight level vestigial sideband (8-VSB) as its digital television modulation standard. In this system, data representing the television program is transmitted as a stream of symbols, each symbol representing three data bits. These symbols are generated at a specified nominal frequency.
[0005] The recovery of data from modulated signals containing digital information in symbol stream form usually requires three functions at a receiver: timing recovery for symbol synchronization, carrier recovery (frequency demodulation to baseband) and channel equalization. The present invention deals specifically with a method and apparatus for more reliable and faster acquisition of symbol timing recovery (STR) over a wider range of STR offset frequencies.
[0006] The symbol timing recovery is a process by which a receiver symbol clock (timebase) is synchronized to the transmitter symbol clock. It permits a received signal to be sampled at optimum points in time to reduce slicing errors associated with decision-directed processing of received symbol values. It is therefore an important purpose of the present invention to provide a timing recovery loop for obtaining symbol synchronization. In order to lock the receiver symbol sampling frequency to the transmitted symbol frequency, the symbol frequency must be acquired, estimated and tracked so that samples can be taken at the correct rate and locations in time. For example, though the system symbol rate can be specified to be 20 megahertz (MHz), the respective frequencies of the oscillators in both the transmitter and the receiver may drift with time and thus the actual symbol frequency differentiate from the specified symbol frequency. The difference between the actual symbol frequency of the received signal and the specified symbol frequency is termed ‘offset’ in the remainder of this application.
[0007] In a known embodiment of a symbol timing recovery circuit, a phase locked loop (PLL) in the receiver generates the symbol clock in synchronism with the received signal. The PLL includes a loop integrator which controls the frequency of a voltage controlled oscillator. A phase comparator, comparing the respective phases of the received signal and the output signal of the voltage controlled oscillator, provides a control signal to the loop integrator, all in a known manner. When a new signal is to be received, the output of the loop integrator must be adjusted such that the frequency of the voltage controlled oscillator is matched to the symbol rate of the new signal, a process termed acquisition.
[0008] The PLL must be able to lock to a range of symbol frequency values in order to receive signals from different transmitters each having their own transmitter clock. As described above, the symbol frequency of the received signal will often be offset from the specified symbol frequency. Equivalently, the term offset may refer to the difference between the value of the loop integrator signal which would condition the loop oscillator to generate a signal locked to the symbols in the received signal and the value of the loop integrator signal which would condition the loop oscillator to generate a signal locked to symbols at the specified frequency.
[0009] There are several problems involved with achieving appropriate symbol timing recovery in the receiver. For example, it may take a long time for the symbol timing recovery circuit to acquire a “lock” on a channel if the starting point of the symbol timing recovery (STR) loop integrator (e.g. the loop integrator output signal for the previous signal) is far away from the eventual locked value for the new signal. The problem becomes even more serious when a narrow STR loop bandwidth is utilized in order to insure reliable acquisition. Indeed, if the STR starting offset is too far away from the locked value, STR loop lock may not be reliably achieved at all. Also, under moderate to strong ghost conditions, symbol timing lock is more reliably achieved when the starting offset is close to the final offset.
SUMMARY OF THE INVENTION
[0010] The present invention relates to a method for establishing timing synchronism between a transmitter symbol clock and a symbol clock in a receiver for receiving a signal formatted as a sequence of symbols at a symbol frequency and subject to exhibiting a symbol timing offset. The method includes steps of calculating a preselected number of offset values for a desired symbol timing recovery (STR) range. The offset values are grouped substantially symmetrically about a central offset value. Each of the preselected offset values is tested to see if symbol timing recovery lock can be achieved by starting at the central value and gradually moving away from the central value. Finally, two timing detection algorithms are used to maximized the possibility of STR lock.
[0011] A further embodiment incorporating principles of the present invention provides a processor for establishing timing synchronism between a transmitter symbol clock and a receiver symbol clock in a receiver for receiving a signal comprising a sequence of symbols at a symbol frequency and subject to exhibiting symbol frequency offset. This embodiment includes means for calculating a preselected number of offset values for a desired symbol timing recovery (STR) range, the offset values being grouped substantially symmetrically about a central offset value. Means are provided for testing each of the preselected offset values to see if symbol timing recovery lock can be achieved by starting at the central offset value and gradually moving away from such central offset value. Also included are means for using two detection algorithms for such testing as well as means for switching between the two algorithms to maximize the possibility of STR lock.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a block diagram of a VSB receiver incorporating the principles of the present invention; and
[0013] FIG. 2 is a flow diagram illustrating the acquisition method according to principles of the present invention.
DETAILED DESCRIPTION
[0014] Referring to the drawings, FIG. 1 is a block diagram of a VSB receiver incorporating the principles of the present invention. A terrestrial broadcast high definition television (HDTV) analog input signal (IN) is received by an antenna (not illustrated). The received signal is a carrier suppressed 8-VSB modulated signal as proposed by the advanced television standards committee (ATSC) television digital standard dated Sep. 16, 1995 adopted by the United States and incorporated herein by reference. Such a VSB signal is represented by a one-dimensional data symbol constellation wherein only one axis contains quantized data to be recovered by the receiver. As noted above, the received signal represents of a stream of data symbols in 8-VSB format, each symbol representing three data bits of the digital television signal. These symbol representative signals occur at a symbol frequency, which may vary from the nominally specified symbol frequency.
[0015] The received signal is applied to an input terminal 10 of a network 20 which includes RF tuning circuits and an IF processor. The IF processor includes a double conversion tuner for producing an IF passband output signal. The network 20 also includes the appropriate automatic gain control (AGC) circuits. The output signal of the network 20 is an IF passband output signal. This signal is applied to an analog-to-digital converter (ADC) 30 which produces an oversampled digital data stream. The ADC 30 oversamples the input 10.76 megasymbols/second VSB symbol data stream at a 21.52 MHz sampling clock rate, which is twice the received symbol rate. This provides an oversampled 21.52 megasamples/second digital data stream with two samples per symbol. The use of such two sample per symbol processing rather than one sample per symbol processing produces advantageous operation of subsequent signal processing functions: such as are associated with the subsequent DC compensation unit 50 ; and symbol phase detectors, as will be described in more detail below.
[0016] The remainder of the circuitry illustrated in FIG. 1 is implemented in the digital domain, rather than the analog domain. Such circuitry may be implemented as dedicated hardware circuitry. However, that circuitry may also be implemented as a digital signal processor arranged to execute a software program to provide the required processing functions, all in a known manner.
[0017] The digital data stream from the ADC 30 is demodulated to baseband by applying the data stream to a network 40 which is an all digital demodulator and carrier recovery network. The network 40 carries out this function by utilizing an all digital phase lock loop (PLL) responsive to a small reference pilot carrier in the received VSB data stream. The unit 40 produces an output I-phase demodulated symbol data stream.
[0018] Associated with the ADC network 30 and the demodulator 40 is a segment sync and symbol clock recovery network 60 . The symbol clock recovery function operates to detect the time locations of the symbols in the input signal. A sample clock is then generated in synchronism with the received symbol stream. As described above, the sample clock is generated at twice the symbol frequency and in synchronism with the received symbols, resulting in two samples per symbol. This sample clock is coupled to the ADC 30 .
[0019] When a new channel is tuned, symbol synchronization must be acquired. This process will be described in more detail below. Once acquired, symbol synchronization must then be maintained, or tracked. The HDTV television signal is transmitted as successive frames, each frame containing two fields, each field containing 313 segments, each segment containing 832 symbols. Each field begins with a field synchronization segment, and each segment, including the field synchronization segments, begins with a four symbol synchronization sequence, all of which have the same fixed value. Network 60 detects the repetitive sync components at the start of each segment in the received data. Segment synchronization signals are supplied (not shown to simplify the figure) to other processing blocks. The time locations of the segment synchronization signals are also detected and used to maintain a properly phased 21.52 MHz sample clock which is used to control the data stream symbol sampling by the ADC 30 , all in a known manner.
[0020] Once circuit 60 acquires a lock on the channel so that the receiver clock is synchronized with the transmitter clock, the VSB receiver is tuned to the appropriate channel, and can function in an appropriate manner. The output of the digital demodulator and carrier recovery circuit 40 is applied to the DC compensation circuit 50 , which compensates for the presence of the pilot tone, described above. The output of the DC compensation circuit 50 is applied to a field sync detector 70 and an NTSC co-channel interference rejection circuit 80 . The output of circuit 80 is applied to an adaptive channel equalizer 90 which corrects channel distortions.
[0021] However phase noise can randomly rotate the symbol constellation so that the output of the equalizer 90 is applied to a phase tracking loop 100 which removes the residual phase and gain noise in the output signal from the equalizer 90 . This includes phase noise which has not been removed by the preceding carrier recovery network 40 in response to the pilot signal.
[0022] The phase corrected signal output from the phase tracking loop 100 is then trellis decoded by the unit 110 deinterleaved by unit 120 , Reed-Solomon error corrected by unit 130 and descrambled or derandomized by unit 140 . Afterwards the decoded data stream is subjected to the audio, video and display processing by the unit 150 .
[0023] The tuner and IF processor unit 20 , the field sync detector 70 , the equalizer 90 , the phase tracking loop 100 , the trellis decoder 110 , the deinterleaver 120 , the Reed-Solomon decoder 130 and the descrambler 140 may employ circuits of the type described in the Grand Alliance HDTV System specification dated April 14 , 1994 . Circuits for performing the functions of the analog-to-digital converter 30 , digital demodulation and carrier recovery 40 and DC compensation 50 are also well known.
[0024] One skilled in the art will understand from the above description that the segment sync signals are used to track the symbol timing. Because the segment signals are a four symbol sequence of a known fixed value, to detect segment sync signals the sample clock supplied to the ADC 30 must already be in synchronism with the symbol timing of the received signal. This is not the case when a new signal is received. Thus, symbol timing must be acquired by a different method that is used to track the symbol timing. That is, when a new channel is tuned, the symbol timing of the newly received signal must be detected, and the sample clock supplied to the ADC 30 must be phased properly to acquire the samples in the newly received signal.
[0025] Two algorithms are known which can detect the phase of symbols in a symbol stream relative to the sample clock without requiring symbol synchronization. The Mueller and Muller and the Gardner algorithms may be utilized in carrying out the acquisition process of the present invention. Both of these algorithms are well known. The Mueller and Muller algorithm is described in the IEEE Transactions on Communications, May, 1976, pages 516-531 and is incorporated herein by reference. The Gardner algorithm is described in the IEEE Transactions on Communications, Vol. Com-34, no. 5, May, 1986 pages 423-428 and is also incorporated herein by reference.
[0026] The Mueller and Muller algorithm is based on one sample per symbol but is decision-directed. The Gardner Algorithm is not decision-directed but generally requires two samples per symbol, one sample of which coincides with the symbol time location. Each of the Mueller and Muller algorithms and the Gardner algorithms has various strengths and weaknesses and neither actually works better than the other at all times. If only one algorithm is used, it will not necessarily operation in all the cases that the symbol timing recovery (STR) must potentially capable of dealing with. The STR timing detector acquisition algorithm of circuit 60 is arranged so that the detector will switch on the fly between the two different symbol timing algorithms to maximize the possibility of STR lock in a manner described in more detail below.
[0027] As described above, the actual symbol frequency may vary, or be offset, from the nominal specified symbol frequency over a range of acceptable symbol frequencies. Furthermore, it is possible that the symbol frequency of a preceding signal is offset toward one end of the range, while the symbol frequency of the newly received signal is offset toward the other end of the range. As described above, in this situation, it may take a long time to acquire the new symbol frequency, or in the worst case, the symbol clock recovery circuit 60 may never acquire the symbol frequency of the new signal.
[0028] In accordance with principles of the present invention, the STR symbol frequency offset in the circuit 60 is set during the acquisition phase to different values chosen from the range of offsets that the STR is likely to traverse. In a preferred embodiment of the present invention the STR offset range is specified to be ±1 kHz. This range is partitioned into nine points which corresponds to offsets of 0, ±200 Hz, ±400 Hz, ±600 Hz, and ±800 Hz from the nominal symbol frequency. Also in accordance with principles of the present invention, in order to quickly and reliably establish timing synchronism between the receiver symbol clock and the transmitter symbol clock, the present invention utilizes the two timing detection algorithms described above.
[0029] FIG. 2 is a flow diagram illustrating the acquisition method according to principles of the present invention. The search algorithm illustrated in FIG. 2 starts at block 602 . In block 604 , one of the two timing detection algorithms described above is selected. In block 606 , for the selected timing algorithm, one of the nine pre-calculated offsets described above is used to generate a sample clock signal for the ADC 30 . In block 608 , starting at that pre-calculated offset, an attempt is made to lock to the newly received signal. In block 610 , a check is made to determine if the lock attempt was successful. If so, then the acquisition method ends in block 612 . Otherwise, a check is made in block 614 to determine of other pre-calculated offset values are still to be tried. If so, then the next pre-calculated offset value is selected in block 606 and another attempt to lock is made in block 608 . If all the pre-calculated offset values have been tried, then in block 616 , a check is made to determine of both timing algorithms have been tried. If not, then the other timing algorithm is tried in block 604 and all the pre-calculated offset values are tried for that timing algorithm. If both timing algorithms have been tried for all pre-calculated offset values and no lock has been achieved, then failure is indicated in block 618 . Alternatively, the acquisition method illustrated in FIG. 2 may be repeated indefinitely.
[0030] As described above, the symbol clock recovery circuit 60 may be implemented as dedicated hardware adapted to implement the function described in FIG. 2 . Alternatively, the symbol clock recovery circuit 60 may include a programmable digital signal processor or microprocessor operating under control of a program which conditions the processor to perform the method illustrated in FIG. 2 . In addition, the symbol timing recovery circuit 60 may include a combination of a programmable processor and dedicated hardware designed to perform selected function under the control of the DSP, all in a known manner.
[0031] Under typical conditions, the frequency offset between the nominal symbol frequency and the actual symbol frequency of a received signal is close to zero, or in other words, near the center of the range of symbol frequencies over which the symbol clock recovery circuit 60 can achieve lock. Occasionally, however, the actual symbol frequency of a received signal is towards the extreme of the specified lock range due to transmitter and/or receiver reference clock errors. Thus, the acquisition method starts in block 606 by selecting an offset at the center or zero kHz in the above noted example and gradually moves outward: i.e. ±200 Hz, then ±400 Hz, then ±600 Hz, and then ±800 Hz, toward the extreme of the lock range. This algorithm arrangement allows a more reliable and faster STR acquisition over a wider range of STR offset frequencies, and in the presence of moderate to strong ghost conditions.
[0032] In the segment sync and symbol clock recovery circuit 60 , as noted above, carrier frequency offsets have been precalculated to cover the anticipated entire range that the STR is likely to traverse. This will guarantee a more reliable acquisition. Since the STR in the circuit 60 has less distance to traverse when starting with a searched offset value it takes less time for the acquisition to be achieved, and provides additional reliability of acquisition.
[0033] In accordance with the principles of the present invention the utilization of the Mueller and Muller algorithm in combination with the Gardner algorithm as well as the arrangement described above for calculating a preselected number of offset values for a desired symbol acquisition range assures quick and accurate “locking” of the receiver clock with the transmitter clock. More reliable acquisition is achieved since as noted above the STR integrator has less distance to traverse when starting with a searched offset value.
[0034] While the present invention has been described with respect to a particular method and a particular illustrative example it is evident that the principles of the present invention may be embodied in other methods and arrangements without departing from the scope of the present invention as defined by the following claims. For example, the Gardner and/or Mueller and Muller symbol timing algorithms may be modified for more accurate acquisition of the particular VSB signal specified for the HDTV transmission system. Alternatively, more symbol timing algorithms than the two discussed above, may be included by including them in the method illustrated in FIG. 2 . In addition, the range of symbol frequencies may be wider than the 1 kHz in the illustrated embodiment, and that range may be divided into more than the nine points in the illustrated embodiment. Furthermore, one skilled in the art will understand that the modulation method is not germane to the present invention. That is, the present invention may also be used with other digital modulation schemes, such as quadrature amplitude modulation (QAM) and quadrature phase shift keyed (QPSK) modulation. | A system is described for establishing timing synchronism between a local receiver symbol clock and a transmitter symbol clock. A prescribed number of offset values are calculated for desired symbol timing range, the offset values being grouped substantially symmetrically about a central offset value. Each of the preselected offset values are tested to see if symbol timing recovery lock can be achieved by starting at the central offset value and gradually moving away from such value. Finally, two timing detection algorithms are used and switched between the two algorithms is carried out as desired to maximize the possibility of STR lock. | 7 |
RELATED APPLICATION
This application claims priority from U.S. provisional patent application No. 60/462,538, filed Apr. 11, 2003, which is hereby incorporated by reference.
BACKGROUND
The present invention relates to a cartridge and method for the preparation of beverages and, in particular, using sealed cartridges which are formed from substantially air- and water-impermeable materials and which contain one or more ingredients for the preparation of beverages.
It has previously been proposed to seal beverage preparation ingredients in individual air-impermeable packages. For example, cartridges or capsules containing compacted ground coffee are known for use in certain coffee preparation machines which are generally termed “espresso” machines. In the production of coffee using these preparation machines the coffee cartridge is placed in a brewing chamber and hot water is passed though the cartridge at relatively high pressures, thereby extracting the aromatic coffee constituents from the ground coffee to produce the coffee beverage. Typically, such machines operate at a pressure of greater than 6×10 5 Pa. The preparation machines of the type described have to date been relatively expensive since components of the machine, such as the water pumps and seals, must be able to withstand the high pressures.
In WO01/58786 there is described a cartridge for the preparation of beverages which operates at a pressure generally in the range 0.7 to 2.0×10 5 Pa. However, the cartridge is designed for use in a beverage preparation machine for the commercial or industrial market and is relatively expensive. Hence, there remains a requirement for a cartridge for the preparation of beverages wherein the cartridges and beverage preparation machine are suitable, in particular, for the domestic market in terms of cost, performance and reliability.
It is known to provide dairy-based beverage ingredients in cartridges in the form of a powder or other dehydrated form. However, consumers consistently indicate that the use of such powdered dairy-based products adversely affects the taste, colour and texture of the final beverage. It has proven difficult to provide liquid dairy-based products in a cartridge due to the requirement to sterilise the cartridge components. Further, it has been found to be difficult to control the dilution and dispensing of the liquid milk products to arrive at a consistent and acceptable final beverage.
SUMMARY
Accordingly, the present invention provides a cartridge containing one or more liquid beverage ingredients and being formed from substantially air- and water-impermeable materials, the cartridge comprising an inlet for the introduction of an aqueous medium into the cartridge, a compartment containing the one or more liquid beverage ingredients and an outlet for a beverage produced by dilution of the one or more liquid beverage ingredients by the aqueous medium, characterised in that the compartment includes means for controlling dilution of at least a proportion of the one or more liquid beverage ingredients on introduction of the aqueous medium into the compartment.
It will be understood that by the term “cartridge” as used herein is meant any package, container, sachet or receptacle which contains one or more beverage ingredients in the manner described. The cartridge may be rigid, semi-rigid or flexible.
The cartridge of the present invention contains one or more liquid beverage ingredients suitable for the formation of a beverage product. The beverage product may be, for example, one of coffee, tea, chocolate, carbonated beverages, or a dairy-based beverage including milk.
Advantageously, the cartridge of the present invention provides superior dilution and dispensing of liquid beverage ingredients by ensuring that the liquid beverage ingredients are dispensed more evenly over the operating cycle rather that being dispensed all at the start of the operating cycle followed by substantially pure aqueous medium, which is, for example, water. This steady dispensation of the liquid beverage ingredients leads to improved homogeneity of the dispensed liquid beverage. In addition, where the diluted liquid beverage is subsequently subjected to foaming, by for example, jetting through an orifice, the improved homogeneity of the liquid leads to a greater consistency of foaming and improved quality and quantity of foam produced per unit volume of liquid beverage.
Preferably, the means for controlling dilution delays dilution of at least a proportion of the one or more liquid beverage ingredients on introduction of the aqueous medium into the compartment.
Preferably, in use, an aqueous medium flow path is established from the inlet to the outlet, the means for delaying dilution comprising a partition which hinders entry of at least a proportion of the one or more liquid beverage ingredients into the aqueous medium flow path. In one embodiment the partition comprises one or more apertures for controllably releasing the at least a proportion of the one or more liquid beverage ingredients into the aqueous medium flow path. Four apertures may be provided.
The partition may comprise a cup-shaped member having an open mouth directed away from the aqueous medium flow path. The cup-shaped member is preferably annular. The one or more apertures are preferably provided at or near a base of the cup-shaped member. The at least a proportion of the liquid beverage ingredients in the cup-shaped member, for example, drain by gravity through the one or more apertures in use.
In one embodiment, the cup-shaped member is spaced from a bottom of the cartridge, such that the aqueous medium flow path passes between the cup-shaped member and the bottom of the cartridge. Consequently, the at least a proportion of the liquid beverage ingredients in the cup-shaped member drains by gravity through the one or more apertures in use vertically downwards into the aqueous medium flow path.
Preferably, the cartridge comprises an inner member and an outer member, wherein the inner member comprises the cup-shaped member. The components of the inner member and the outer member may more easily be sterilised prior to assembly when they are separated. Once the components are conjoined a number of small-apertured, tortuous pathways are created which cannot effectively be sterilised using known methods. The ability to sterilise the components is a particularly advantageous feature where the cartridges are used for dispensing dairy-based beverages such as milk.
Preferably, the cartridge further comprises means for producing a jet of the beverage, wherein said means for producing the jet of the beverage comprises an aperture in the aqueous medium flow path. The aperture may be delimited by an interface between the inner member and the outer member.
Preferably, the cartridge further comprises at least one inlet for air and means for generating a pressure reduction of the jet of beverage, whereby, in use, air from the at least one air inlet is incorporated into the beverage as a plurality of small bubbles. At least one air inlet may be provided in the inner member downstream of the aperture.
In one embodiment the at least one air inlet and means for producing a pressure reduction in the jet of beverage produces a foaming of the one or more liquid beverage ingredients of greater than 40%. Preferably, greater than 70%. Preferably, the cartridge is disc-shaped. The outer member and/or inner member are formed, for example, from polypropylene.
In one example, the liquid beverage ingredient is a concentrated liquid milk composition. Preferably, the concentrated liquid milk contains between 25 and 40% total solids. More preferably, the concentrated liquid milk contains 30% total solids. Also preferably, the concentrated liquid milk contains between 0.1 and 12% fat. Alternatively, the one or more liquid beverage ingredients are selected from the group of cocoa solids, coffee, tea, sweeteners, cordials, flavourings, alcoholic beverages, flavoured milk, fruit juices, squashes, sauces and desserts.
The present invention also provides a method of dispensing a beverage from a cartridge containing one or more liquid beverage ingredients during an operating cycle, comprising the steps of passing an aqueous medium through the cartridge to form a beverage by dilution of said one or more beverage ingredients, and dispensing the beverage into a receptacle, wherein the one or more liquid ingredients as dispensed has a concentration at the start of the operating cycle of between 30 and 70% total solids and a concentration at the end of the operating cycle of between 1 and 15% total solids.
In one embodiment the concentration at the start of the operating cycle is between 30 and 35% total solids. The concentration at the end of the operating cycle is approximately 10% total solids. The liquid ingredient may be concentrated milk. In another embodiment, the concentration at the start of the operating cycle is between 60 and 70% total solids. The concentration at the end of the operating cycle is between 12 and 15% total solids. The liquid ingredient may contain cocoa solids. In another embodiment, the concentration at the start of the operating cycle is between 40 and 70% total solids. The concentration at the end of the operating cycle is between 1 and 2% total solids. The liquid ingredient may contain coffee.
The present invention further provides a method of dispensing a beverage from a cartridge containing one or more liquid beverage ingredients during an operating cycle, comprising the steps of passing an aqueous medium through the cartridge to form a beverage by dilution of said one or more beverage ingredients, and dispensing the beverage into a receptacle, wherein the one or more liquid beverage ingredients is foamed on dispense to a ratio of between 20 and 150%.
Preferably the one or more liquid beverage ingredients are foamed to a ratio between 70 and 100%.
The one or more liquid beverage ingredients may include one or more of concentrated milk, coffee and cocoa solids.
The present invention further provides a beverage as produced by the above methods.
In the following description the terms “upper” and “lower” and equivalents will be used to describe the relational positioning of features of the invention. The terms “upper” and “lower” and equivalents should be understood to refer to the cartridge (or other components) in its normal orientation for insertion into a beverage preparation machine and subsequent dispensing as shown, for example, in FIG. 4 . In particular, “upper” and “lower” refer, respectively, to relative positions nearer or further from a top surface 11 of the cartridge. In addition, the terms “inner” and “outer” and equivalents will be used to describe the relational positioning of features of the invention. The terms “inner” and “outer” and equivalents should be understood to refer to relative positions in the cartridge (or other components) being, respectively, nearer or further from a centre or major axis X of the cartridge 1 (or other component).
BRIEF DESCRIPTION OF DRAWINGS
Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is cross-sectional drawing of an outer member of first and second embodiments of cartridge;
FIG. 2 is a cross-sectional drawing of a detail of the outer member of FIG. 1 showing an inwardly directed cylindrical extension;
FIG. 3 is a cross-sectional drawing of a detail of the outer member of FIG. 1 showing a slot;
FIG. 4 is a perspective view from above of the outer member of FIG. 1 ;
FIG. 5 is a perspective view from above of the outer member of FIG. 1 in an inverted orientation;
FIG. 6 is a plan view from above of the outer member of FIG. 1 ;
FIG. 7 is a cross-sectional drawing of an inner member of the first embodiment of cartridge;
FIG. 8 is a perspective view from above of the inner member of FIG. 7 ;
FIG. 9 is a perspective view from above of the inner member of FIG. 7 in an inverted orientation;
FIG. 10 is a plan view from above of the inner member of FIG. 7 ;
FIG. 11 is a cross-sectional drawing of the first embodiment of cartridge in an assembled condition;
FIG. 12 is a cross-sectional drawing of an inner member of the second embodiment of cartridge;
FIG. 13 is a cross-sectional drawing of a detail of the inner member of FIG. 12 showing an aperture;
FIG. 14 is a perspective view from above of the inner member of FIG. 12 ;
FIG. 15 is a perspective view from above of the inner member of FIG. 12 in an inverted orientation;
FIG. 16 is another cross-sectional drawing of the inner member of FIG. 12 ;
FIG. 17 is a cross-sectional drawing of another detail of the inner member of FIG. 12 showing an air inlet;
FIG. 18 is a cross-sectional drawing of the second embodiment of cartridge in an assembled condition;
FIG. 19 is cross-sectional drawing of an outer member of third and fourth embodiments of cartridge, the fourth embodiment being according to the present invention;
FIG. 20 is a cross-sectional drawing of a detail of the outer member of FIG. 19 showing an inwardly directed cylindrical extension;
FIG. 21 is a plan view from above of the outer member of FIG. 19 ;
FIG. 22 is a perspective view from above of the outer member of FIG. 19 ;
FIG. 23 is a perspective view from above of the outer member of FIG. 19 in an inverted orientation;
FIG. 24 is a cross-sectional drawing of an inner member of the third embodiment of cartridge;
FIG. 25 is a plan view from above of the inner member of FIG. 24 ;
FIG. 26 is a cross-sectional drawing of a detail of the inner member of FIG. 24 showing an in-turned upper rim;
FIG. 27 is a perspective view from above of the inner member of FIG. 24 ;
FIG. 28 is a perspective view from above of the inner member of FIG. 24 in an inverted orientation;
FIG. 29 is a cross-sectional drawing of the third embodiment of cartridge in an assembled condition;
FIG. 30 is a cross-sectional drawing of an inner member of the fourth embodiment of cartridge according to the present invention;
FIG. 31 is a plan view from above of the inner member of FIG. 30 ;
FIG. 32 is a perspective view from above of the inner member of FIG. 30 ;
FIG. 33 is a perspective view from above of the inner member of FIG. 30 in an inverted orientation;
FIG. 34 is a cross-sectional drawing of the fourth embodiment of cartridge in an assembled condition;
FIG. 35 a is a graph of concentration vs. operating cycle time;
FIG. 35 b is a graph of foamability vs. operating cycle time; and
FIG. 35 c is a graph of temperature vs. operating cycle time.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As shown in FIG. 11 , the cartridge 1 generally comprises an outer member 2 , an inner member 3 and a laminate 5 . The outer member 2 , inner member 3 and laminate 5 are assembled to form the cartridge 1 which has an interior 120 for containing one or more beverage ingredients, an inlet 121 , an outlet 122 and a beverage flow path linking the inlet 121 to the outlet 122 and which passes through the interior 120 . The inlet 121 and outlet 122 are initially sealed by the laminate 5 and are opened in use by piercing or cutting of the laminate 5 . The beverage flow path is defined by spatial inter-relationships between the outer member 2 , inner member 3 and laminate 5 as discussed below. Other components may optionally be included in the cartridge 1 , such as a filter 4 , as will be described further below.
A first version of cartridge 1 which will be described for background purposes is shown in FIGS. 1 to 11 . The first version of the cartridge 1 is particularly designed for use in dispensing filtered products such as roast and ground coffee or leaf tea. However, this version of the cartridge 1 and the other versions described below may be used with other products such as chocolate, coffee, tea, sweeteners, cordials, flavourings, alcoholic beverages, flavoured milk, fruit juices, squashes, sauces and desserts.
As can be seen from FIG. 5 , the overall shape of the cartridge 1 is generally circular or disc-shaped with the diameter of the cartridge 1 being significantly greater than its height. A major axis X passes through the centre of the outer member as shown in FIG. 1 . Typically the overall diameter of the outer member 2 is 74.5 mm±6 mm and the overall height is 16 mm±3 mm. Typically the volume of the cartridge 1 when assembled is 30.2 ml±20%.
The outer member 2 generally comprises a bowl-shaped shell 10 having a curved annular wall 13 , a closed top 11 and an open bottom 12 . The diameter of the outer member 2 is smaller at the top 11 compared to the diameter at the bottom 12 , resulting from a flaring of the annular wall 13 as one traverses from the closed top 11 to the open bottom 12 . The annular wall 13 and closed bottom 11 together define a receptacle having an interior 34 .
A hollow inwardly directed cylindrical extension 18 is provided in the closed top 11 centred on the major axis X. As more clearly shown in FIG. 2 , the cylindrical extension 18 comprises a stepped profile having first, second and third portions 19 , 20 and 21 . The first portion 19 is right circular cylindrical. The second portion 20 is frusto-conical in shape and is inwardly tapered. The third portion 21 is another right circular cylinder and is closed off by a lower face 31 . The diameter of the first, second and third portion 19 , 20 and 21 incrementally decreases such that the diameter of the cylindrical extension 18 decreases as one traverses from the top 11 to the closed lower face 31 of the cylindrical extension 18 . A generally horizontal shoulder 32 is formed on the cylindrical extension 18 at the junction between the second and third portions 20 and 21 .
An outwardly extending shoulder 33 is formed in the outer member 2 towards the bottom 12 . The outwardly extending shoulder 33 forms a secondary wall 15 co-axial with the annular wall 13 so as to define an annular track forming a manifold 16 between the secondary wall 15 and the annular wall 13 . The manifold 16 passes around the circumference of the outer member 2 . A series of slots 17 are provided in the annular wall 13 level with the manifold 16 to provide gas and liquid communication between the manifold 16 and the interior 34 of the outer member 2 . As shown in FIG. 3 , the slots 17 comprise vertical slits in the annular wall 13 . Between 20 and 40 slots are provided. In the embodiment shown thirty-seven slots 17 are provided generally equi-spaced around the circumference of the manifold 16 . The slots 17 are preferably between 1.4 and 1.8 mm in length. Typically the length of each slot is 1.6 mm representing 10% of the overall height of the outer member 2 . The width of each slot is between 0.25 and 0.35 mm. Typically, the width of each slot is 0.3 mm. The width of the slots 17 is sufficiently narrow to prevent the beverage ingredients passing therethrough into the manifold 16 either during storage or in use.
An inlet chamber 26 is formed in the outer member 2 at the periphery of the outer member 2 . A cylindrical wall 27 is provided, as most clearly shown in FIG. 5 , which defines the inlet chamber 26 within, and partitions the inlet chamber 26 from, the interior 34 of the outer member 2 . The cylindrical wall 27 has a closed upper face 28 which is formed on a plane perpendicular to the major axis X and an open lower end 29 co-planar with the bottom 12 of the outer member 2 . The inlet chamber 26 communicates with the manifold 16 via two slots 30 as shown in FIG. 1 . Alternatively, between one and four slots may be used to communicate between the manifold 16 and the inlet chamber 26 .
A lower end of the outwardly extending shoulder 33 is provided with an outwardly extending flange 35 which extends perpendicularly to the major axis X. Typically the flange 35 has a width of between 2 and 4 mm. A portion of the flange 35 is enlarged to form a handle 24 by which the outer member 2 may be held. The handle 24 is provided with an upturned rim 25 to improve grip.
The outer member 2 is formed as a single integral piece from high density polyethylene, polypropylene, polystyrene, polyester, or a laminate of two or more of these materials. A suitable polypropylene is the range of polymers available from DSM UK Limited (Redditch, United Kingdom). The outer member may be opaque, transparent or translucent. The manufacturing process may be injection moulding.
The inner member 3 as shown in FIGS. 7 to 10 , comprises an annular frame 41 and a downwardly extending cylindrical funnel 40 . A major axis X passes through the centre of the inner member 3 as shown in FIG. 7 .
As best shown in FIG. 8 , the annular frame 41 comprises an outer rim 51 and an inner hub 52 joined by ten equi-spaced radial spokes 53 . The inner hub 52 is integral with and extends from the cylindrical funnel 40 . Filtration apertures 55 are formed in the annular frame 41 between the radial spokes 53 . A filter 4 is disposed on the annular frame 41 so as to cover the filtration apertures 55 . The filter is preferably made from a material with a high wet strength, for example a non-woven fibre material of polyester. Other materials which may be used include a water-impermeable cellulosic material, such as a cellulosic material comprising woven paper fibres. The woven paper fibres may be admixed with fibres of polypropylene, polyvinyl chloride and/or polyethylene. The incorporation of these plastic materials into the cellulosic material renders the cellulosic material heat-sealable. The filter 4 may also be treated or coated with a material which is activated by heat and/or pressure so that it can be sealed to the annular frame 41 in this way.
As shown in the cross-sectional profile of FIG. 7 , the inner hub 52 is located at a lower position than the outer rim 51 , resulting in the annular frame 41 having a sloping lower profile.
The upper surface of each spoke 53 is provided with an upstanding web 54 which divides a void space above the annular frame 41 into a plurality of passages 57 . Each passage 57 is bounded on either side by a web 54 and on a lower face by the filter 4 . The passages 57 extend from the outer rim 51 downwardly towards, and open into, the cylindrical funnel 40 at openings 56 defined by the inner extremities of the webs 54 .
The cylindrical funnel 40 comprises an outer tube 42 surrounding an inner discharge spout 43 . The outer tube 42 forms the exterior of the cylindrical funnel 40 . The discharge spout 43 is joined to the outer tube 42 at an upper end of the discharge spout 43 by means of an annular flange 47 . The discharge spout 43 comprises an inlet 45 at an upper end which communicates with the openings 56 of the passages 57 and an outlet 44 at a lower end through which the prepared beverage is discharged into a cup or other receptacle. The discharge spout 43 comprises a frusto-conical portion 48 at an upper end and a cylindrical portion 58 at a lower end. The cylindrical portion 58 may have a slight taper such that it narrows towards the outlet 44 . The frusto-conical portion 48 helps to channel beverage from the passages 57 down towards the outlet 44 without inducing turbulence to the beverage. An upper surface of the frusto-conical portion 48 is provided with four support webs 49 equi-spaced around the circumference of the cylindrical funnel 40 . The support webs 49 define channels 50 therebetween. The upper edges of the support webs 49 are level with one another and perpendicular to the major axis X.
The inner member 3 may be formed as a single integral piece from polypropylene or a similar material as described above and by injection moulding in the same manner as the outer member 2 .
Alternatively, the inner member 3 and/or the outer member 2 may be made from a biodegradable polymer. Examples of suitable materials include degradable polyethylene (for example, SPITEK supplied by Symphony Environmental, Borehamwood, United Kingdom), biodegradable polyester amide (for example, BAK 1095 supplied by Symphony Environmental), poly lactic acids (PLA supplied by Cargil, Minn., USA), starch-based polymers, cellulose derivatives and polypeptides.
The laminate 5 is formed from two layers, a first layer of aluminium and a second layer of cast polypropylene. The aluminium layer is between 0.02 and 0.07 mm in thickness. The cast polypropylene layer is between 0.025 and 0.065 mm in thickness. In one embodiment the aluminium layer is 0.06 mm and the polypropylene layer is 0.025 mm thick. This laminate is particularly advantageous as it has a high resistance to curling during assembly. As a result the laminate 5 may be pre-cut to the correct size and shape and subsequently transferred to the assembly station on the production line without undergoing distortion. Consequently, the laminate 5 is particularly well suited to welding. Other laminate materials may be used including PET/Aluminium/PP, PE/EVOH/PP, PET/metallised/PP and Aluminium/PP laminates. Roll laminate stock may be used instead of die cut stock.
The cartridge 1 may be closed by a rigid or semi-rigid lid instead of a flexible laminate.
Assembly of the cartridge 1 involves the following steps:
a) the inner member 3 is inserted into the outer member 2 ; b) the filter 4 is cut to shape and placed onto the inner member 3 so to be received over the cylindrical funnel 40 and come to rest against the annular frame 41 ; c) the inner member 3 , outer member 2 and filter 4 are joined by ultrasonic welding; d) the cartridge 1 is filled with one or more beverage ingredients; e) the laminate 5 is affixed to the outer member 2 .
These steps will be discussed in greater detail below.
The outer member 2 is orientated with the open bottom 12 directed upwards. The inner member 3 is then inserted into the outer member 2 with the outer rim 51 being received as a loose fit in an axial extension 14 at top 11 of the cartridge 1 . The cylindrical extension 18 of the outer member 2 is at the same time received in the upper portion of the cylindrical funnel 40 of the inner member 3 . The third portion 21 of the cylindrical extension 18 is seated inside the cylindrical funnel 40 with the closed lower face 31 of the cylindrical extension 18 bearing against the support webs 49 of the inner member 3 . The filter 4 is then placed over the inner member 3 such that the filter material contacts the annular rim 51 . An ultrasonic welding process is then used to join the filter 4 to the inner member 3 and at the same time, and in the same process step, the inner member 3 to the outer member 2 . The inner member 3 and filter 4 are welded around the outer rim 51 . The inner member 3 and outer member 2 are joined by means of weld lines around the outer rim 51 and also the upper edges of the webs 54 .
As shown most clearly in FIG. 11 , the outer member 2 and inner member 3 when joined together define a void space 130 in the interior 120 below the annular flange 41 and exterior the cylindrical funnel 40 which forms a filtration chamber. The filtration chamber 130 and passages 57 above the annular frame 41 are separated by the filter paper 4 .
The filtration chamber 130 contains the one or more beverage ingredients 200 . The one or more beverage ingredients are packed into the filtration chamber 130 . For a filtered style beverage the ingredient is typically roast and ground coffee or leaf tea. The density of packing of the beverage ingredients in the filtration chamber 130 can be varied as desired. Typically, for a filtered coffee product the filtration chamber contains between 5.0 and 10.2 grams of roast and ground coffee in a filtration bed of thickness of typically 5 to 14 mm. Optionally, the interior 120 may contain one or more bodies, such as spheres, which are freely movable within the interior 120 to aid mixing by inducing turbulence and breaking down deposits of beverage ingredients during discharge of the beverage.
The laminate 5 is then affixed to the outer member 2 by forming a weld 126 around the periphery of the laminate 5 to join the laminate 5 to the lower surface of the outwardly extending flange 35 . The weld 126 is extended to seal the laminate 5 against the lower edge of the cylindrical wall 27 of the inlet chamber 26 . Further, a weld 125 is formed between the laminate 5 and the lower edge of the outer tube 42 of the cylindrical funnel 40 . The laminate 5 forms the lower wall of the filtration chamber 130 and also seals the inlet chamber 26 and cylindrical funnel 40 . However, a small gap 123 exists prior to dispensation between the laminate 5 and the lower edge of the discharge spout 43 . A variety of welding methods may be used, such as heat and ultrasonic welding, depending on the material characteristics of the laminate 5 .
Advantageously, the inner member 3 spans between the outer member 2 and the laminate 5 . The inner member 3 is formed from a material of relative rigidity, such as polypropylene. As such, the inner member 3 forms a load-bearing member that acts to keep the laminate 5 and outer member 2 spaced apart when the cartridge 1 is compressed. It is preferred that the cartridge 1 is subjected to a compressive load of between 130 and 280N in use. The compressive force acts to prevent the cartridge failing under internal pressurisation and also serves to squeeze the inner member 3 and outer member 2 together. This ensures that the internal dimensions of passageways and apertures in the cartridge 1 are fixed and unable to change during pressurisation of the cartridge 1 .
To use the cartridge 1 it is first inserted into a beverage preparation machine and the inlet 121 and outlet 122 are opened by piercing members of the beverage preparation machine which perforate and fold back the laminate 5 . An aqueous medium, typically water, under pressure enters the cartridge 1 through the inlet 121 into the inlet chamber 26 at a pressure of between 0.1-2.0 bar. From there the water is directed to flow through the slots 30 and round the manifold 16 and into the filtration chamber 130 of the cartridge 1 through the plurality of slots 17 . The water is forced radially inwardly through the filtration chamber 130 and mixes with the beverage ingredients 200 contained therein. The water is at the same time forced upwardly through the beverage ingredients. The beverage formed by passage of the water through the beverage ingredients passes through the filter 4 and filtration apertures 55 into the passages 57 lying above the annular frame 41 . The sealing of the filter 4 onto the spokes 53 and the welding of the rim 51 with the outer member 2 ensures that there are no short-circuits and all the beverage has to pass through the filter 4 .
The beverage then flows downwardly along the radial passages 57 formed between the webs 54 and through the openings 56 and into the cylindrical funnel 40 . The beverage passes along the channels 50 between the support webs 47 and down the discharge spout 43 to the outlet 44 where the beverage is discharged into a receptacle such as a cup.
Preferably, the beverage preparation machine comprises an air purge facility, wherein compressed air is forced through the cartridge 1 at the end of the operating cycle to flush out the remaining beverage into the receptacle.
A second version of cartridge 1 will now be described for background purposes with reference to FIGS. 12 to 18 . The second version of the cartridge 1 is particularly designed for use in dispensing espresso-style products such as roast and ground coffee where it is desirable to produce a beverage having a froth of tiny bubbles known as a crema. Many of the features of the second version of the cartridge 1 are the same as in the first version and like numerals have been used to reference like features. In the following description the differences between the first and second versions will be discussed. Common features which function in the same manner will not be discussed in detail.
The outer member 2 is of the same construction as in the first version of cartridge 1 and as shown in FIGS. 1 to 6 .
The annular frame 41 of the inner member 3 is the same as in the first version. Also, a filter 4 is disposed on the annular frame 41 so as to cover the filtration apertures 55 . The outer tube 42 of the cylindrical funnel 40 is also as before. However, there are a number of differences in the construction of the inner member 2 of the second version compared to the first version. As shown in FIG. 16 , the discharge spout 43 is provided with a partition 65 which extends part way up the discharge spout 43 from the outlet 44 . The partition 65 helps to prevent the beverage spraying and/or splashing as it exits the discharge spout 43 . The profile of the discharge spout 43 is also different and comprises a stepped profile with a distinct dog-leg 66 near an upper end of the tube 43 .
A rim 67 is provided upstanding from the annular flange 47 joining the outer tube 42 to the discharge spout 43 . The rim 67 surrounds the inlet 45 to the discharge spout 43 and defines an annular channel 69 between the rim 67 and the upper portion of the outer tube 42 . The rim 67 is provided with an inwardly directed shoulder 68 . At one point around the circumference of the rim 67 an aperture 70 is provided in the form of a slot which extends from an upper edge of rim 67 to a point marginally below the level of the shoulder 68 as most clearly shown in FIGS. 12 and 13 . The slot has a width of 0.64 mm.
An air inlet 71 is provided in annular flange 47 circumferentially aligned with the aperture 70 as shown in FIGS. 16 and 17 . The air inlet 71 comprises an aperture passing through the flange 47 so as to provide communication between a point above the flange 47 and the void space below the flange 47 between the outer tube 42 and discharge spout 43 . Preferably, and as shown, the air inlet 71 comprises an upper frusto-conical portion 73 and a lower cylindrical portion 72 . The air inlet 71 is typically formed by a mould tool such as a pin. The tapered profile of the air inlet 71 allows the mould tool to be more easily removed from the moulded component. The wall of the outer tube 42 in the vicinity of the air inlet 71 is shaped to form a chute 75 leading from the air inlet 71 to the inlet 45 of the discharge spout 43 . As shown in FIG. 17 , a canted shoulder 74 is formed between the air inlet 71 and the chute 75 to ensure that the jet of beverage issuing from the slot 70 does not immediately foul on the upper surface of the flange 47 in the immediate vicinity of the air inlet 71 .
The assembly procedure for the second version of cartridge 1 is similar to the assembly of the first version. However, there are certain differences. As shown in FIG. 18 , the third portion 21 of the cylindrical extension 18 is seated inside the support rim 67 rather than against support webs. The shoulder 32 of the cylindrical extension 18 between the second portion 20 and third portion 21 bears against the upper edge of the support rim 67 of the inner member 3 . An interface zone 124 is thus formed between the inner member 3 and the outer member 2 comprising a face seal between the cylindrical extension 18 and the support rim 67 which extends around nearly the whole circumference of the cartridge 1 . The seal between the cylindrical extension 18 and the support rim 67 is not fluid-tight though since the slot 70 in the support rim 67 extends through the support rim 67 and downwardly to a point marginally below the shoulder 68 . Consequently the interface fit between the cylindrical extension 18 and the support rim 67 transforms the slot 70 into an aperture 128 , as most clearly shown in FIG. 18 , providing gas and liquid communication between the annular channel 69 and the discharge spout 43 . The aperture is typically 0.64 mm wide by 0.69 mm long.
Operation of the second version of cartridge 1 to dispense a beverage is similar to the operation of the first version but with certain differences. Beverage in the radial passages 57 flows downwardly along the passages 57 formed between the webs 54 and through the openings 56 and into the annular channel 69 of the cylindrical funnel 40 . From the annular channel 69 the beverage is forced under pressure through the aperture 128 by the back pressure of beverage collecting in the filtration chamber 130 and passages 57 . The beverage is thus forced through aperture 128 as a jet and into an expansion chamber formed by the upper end of the discharge spout 43 . As shown in FIG. 18 , the jet of beverage passes directly over the air inlet 71 . As the beverage enters the discharge spout 43 the pressure of the beverage jet drops. As a result air is entrained into the beverage stream in the form of a multitude of small air bubbles as the air is drawn up through the air inlet 71 . The jet of beverage issuing from the aperture 128 is funnelled downwards to the outlet 44 where the beverage is discharged into a receptacle such as a cup where the air bubbles form the desired crema. Thus, the aperture 128 and the air inlet 71 together form an eductor which acts to entrain air into the beverage. Flow of beverage into the eductor should be kept as smooth as possible to reduce pressure losses. Advantageously, the walls of the eductor should be made concave to reduce losses due to ‘wall effect’ friction. The dimensional tolerance of the aperture 128 is small. Preferably the aperture size is fixed plus or minus 0.02 mm 2 . Hairs, fibrils or other surface irregularities can be provided within or at the exit of the eductor to increase the effective cross-sectional area which has been found to increase the degree of air entrainment.
A third version of cartridge 1 will now be described for background purposes and is shown in FIGS. 19 to 29 . The third version of the cartridge 1 is particularly designed for use in dispensing soluble products which may be in powdered, liquid, syrup, gel or similar form. The soluble product is dissolved by or forms a suspension in, an aqueous medium such as water when the aqueous medium is passed, in use, through the cartridge 1 . Examples of beverages include chocolate, coffee, milk, tea, soup or other rehydratable or aqueous-soluble products. Many of the features of the third version of the cartridge 1 are the same as in the previous versions and like numerals have been used to reference like features. In the following description the differences between the third and previous versions will be discussed. Common features which function in the same manner will not be discussed in detail.
Compared to the outer member 2 of the previous versions, the hollow inwardly directed cylindrical extension 18 of the outer member 2 of the third version has a larger overall diameter as shown in FIG. 20 . In particular the diameter of the first portion 19 is typically between 16 and 18 mm compared to 13.2 mm for the outer member 2 of the previous versions. In addition, the first portion 19 is provided with a convex outer surface 19 a , or bulge, as most clearly shown in FIG. 20 , the function of which will be described below. The diameter of the third portions 21 of the cartridges 1 are however the same resulting in the area of the shoulder 32 being greater in this, the third version of the cartridge 1 . Typically the volume of the cartridge 1 when assembled is 32.5 ml±20%.
The number and positioning of the slots in the lower end of the annular wall 13 is also different. Between 3 and 5 slots are provided. In the embodiment as shown in FIG. 23 , four slots 36 are provided equi-spaced around the circumference of the manifold 16 . The slots 36 are slightly wider than in the previous versions of the cartridge 1 being between 0.35 and 0.45 mm, preferably 0.4 mm wide.
In other respects the outer members 2 of the cartridges 1 are the same.
The construction of the cylindrical funnel 40 of the inner member 3 is the same as in the first version of cartridge 1 with an outer tube 42 , discharge spout 45 , annular flange 47 and support webs 49 being provided. The only difference is that the discharge spout 45 is shaped with an upper frusto-conical section 92 and a lower cylindrical section 93 .
In contrast to the previous versions and as shown in FIGS. 24 to 28 , the annular frame 41 is replaced by a skirt portion 80 which surrounds the cylindrical funnel 40 and is joined thereto by means of eight radial struts 87 which adjoin the cylindrical funnel 40 at or near the annular flange 47 . A cylindrical extension 81 of the skirt portion 80 extends upwardly from the struts 87 to define a chamber 90 with an open upper face. An upper rim 91 of the cylindrical extension 81 has an in-turned profile as shown in FIG. 26 . An annular wall 82 of the skirt portion 80 extends downwardly from the struts 87 to define an annular channel 86 between the skirt portion 80 and the outer tube 42 .
The annular wall 82 comprises at a lower end an exterior flange 83 which lies perpendicular to the major axis X. A rim 84 depends downwardly from a lower surface of the flange 83 and contains five apertures 85 which are circumferentially equi-spaced around the rim 84 . Thus, the rim 84 is provided with a castellated lower profile.
Apertures 89 are provided between the struts 87 allowing communication between the chamber 90 and the annular channel 86 .
The assembly procedure for the third version of cartridge 1 is similar to the assembly of the first version but with certain differences. The outer member 2 and inner member 3 are push-fitted together as shown in FIG. 29 and retained by means of a snap-fit arrangement rather than welded together. On joining the two members the inwardly directed cylindrical extension 18 is received inside the upper cylindrical extension 81 of the skirt portion 80 . The inner member 3 is retained in the outer member 2 by frictional interengagement of the convex outer surface 19 a of the first portion 19 of the cylindrical extension 18 with the in-turned rim 91 of the upper cylindrical extension 81 . With the inner member 3 located in the outer member 2 a mixing chamber 134 is defined located exterior to the skirt portion 80 . The mixing chamber 134 contains the beverage ingredients 200 prior to dispensation. It should be noted that the four inlets 36 and the five apertures 85 are staggered circumferentially with respect to one another. The radial location of the two parts relative to each other need not be determined or fixed during assembly since the use of four inlets 36 and five apertures 85 ensures that misalignment occurs between the inlets and apertures whatever the relative rotational positioning of the components.
The one or more beverage ingredients are packed into the mixing chamber 134 of the cartridge. The density of packing of the beverage ingredients in the mixing chamber 134 can be varied as desired.
The laminate 5 is then affixed to the outer member 2 and inner member 3 in the same manner as described above in the previous versions.
In use, water enters the mixing chamber 134 through the four slots 36 in the same manner as previous versions of the cartridge. The water is forced radially inwardly through the mixing chamber and mixes with the beverage ingredients contained therein. The product is dissolved or mixed in the water and forms the beverage in the mixing chamber 134 and is then driven though the apertures 85 into the annular channel 86 by back pressure of beverage and water in the mixing chamber 134 . The circumferential staggering of the four inlet slots 36 and the five apertures 85 ensures that jets of water are not able to pass radially directly from the inlet slots 36 to the apertures 85 without first circulating within the mixing chamber 134 . In this way the degree and consistency of dissolution or mixing of the product is significantly increased. The beverage is forced upwardly in the annular channel 86 , through the apertures 89 between the struts 87 and into the chamber 90 . The beverage passes from chamber 90 through the inlets 45 between the support webs 49 into the discharge spout 43 and towards the outlet 44 where the beverage is discharged into a receptacle such as a cup. The cartridge finds particular application with beverage ingredients in the form of viscous liquids or gels. In one application a liquid chocolate ingredient is contained in the cartridge 1 with a viscosity of between 1700 and 3900 mPa at ambient temperature and between 5000 and 10000 mPa at 0° C. and a refractive solids of 67 Brix±3. In another application liquid coffee is contained in the cartridge 1 with a viscosity of between 70 and 2000 mPa at ambient and between 80 and 5000 mPa at 0° C. where the coffee has a total solids level of between 40 and 70%. The liquid coffee ingredient may contain between 0.1 and 2.0% by weight sodium bicarbonate, preferably between 0.5 and 1.0% by weight. The sodium bicarbonate acts to maintain the pH level of the coffee at or below 4.8 enabling a shelf-life for coffee-filled cartridges of up to 12 months.
A fourth version of cartridge 1 embodying the present invention is shown in FIGS. 30 to 34 . The fourth version of the cartridge 1 is particularly designed for use in dispensing liquid products such as concentrated liquid milk. Many of the features of the fourth version of the cartridge 1 are the same as in the previous versions and like numerals have been used to reference like features. In the following description the differences between the fourth and previous versions will be discussed. Common features which function in the same manner will not be discussed in detail.
The outer member 2 is the same as in the third version of cartridge 1 and as shown in FIGS. 19 to 23 .
The cylindrical funnel 40 of the inner member 3 is similar to that shown in the second version of cartridge 1 but with certain differences. As shown in FIG. 30 the discharge spout 43 is shaped with an upper frusto-conical section 106 and a lower cylindrical section 107 . Three axial ribs 105 are provided on the inner surface of the discharge spout 43 to direct the dispensed beverage downwards towards the outlet 44 and prevent the discharged beverage from spinning within the spout. Consequently, the ribs 105 act as baffles. As in the second version of cartridge 1 , an air inlet 71 is provided through the annular flange 47 . However, the chute 75 beneath the air inlet 71 is more elongated than in the second version.
A skirt portion 80 is provided similar to that shown in the third version of the cartridge 1 described above. Between 5 and 12 apertures 85 are provided in the rim 84 . Typically ten apertures are provided rather than the five provided in the third version of cartridge 1 .
An annular bowl 100 is provided extending from and integral with the flange 83 of the skirt portion 80 . The annular bowl 100 comprises a flared body 101 with an open upper mouth 104 which is directed upwards. Four feed apertures 103 shown in FIGS. 30 and 31 are located in the body 101 at or near the lower end of the bowl 100 where it joins the skirt portion 80 . Preferably, the feed apertures are equi-spaced around the circumference of the bowl 100 . The bowl 100 joins the skirt portion 80 part-way up its length such that a discrete gap is provided between the bowl 100 and the laminate 5 when the cartridge is assembled. Thus, the apertures 85 are located below the level of the bowl 100 . As can be seen from FIG. 34 , when the cartridge 1 is assembled and filled the bowl 100 contains a proportion of the liquid beverage ingredients therein, effectively partitioning that proportion of the beverage ingredients from the apertures 85 .
The laminate 5 is of the type described above in the previous embodiments.
The assembly procedure for the fourth version of cartridge 1 is the same as that for the third version.
Operation of the fourth version of cartridge is similar to that of the third version. The water enters the cartridge 1 and the mixing chamber 134 in the same manner as before. There the water mixes with and dilutes the liquid product which is then forced out below the bowl 100 and through the apertures 85 towards the outlet 44 as described above. The proportion of the liquid product initially contained within the annular bowl 100 as shown in FIG. 34 is not subject to immediate dilution by the water entering the mixing chamber 134 . Rather, the diluted liquid product in the lower part of the mixing chamber 134 will tend to exit through apertures 85 rather than be forced up and into the annular bowl 100 through upper mouth 104 . Consequently, the liquid product in the annular bowl 100 will remain relatively concentrated during the initial stages of the operating cycle compared to the product in the lower part of the mixing chamber 134 . The liquid product in the annular bowl 100 drips through the feed apertures 103 under gravity into the stream of product exiting the mixing chamber 134 through the apertures 85 and below the bowl 100 . The annular bowl 100 acts to even out the concentration of the diluted liquid product entering the cylindrical funnel 40 by holding back a proportion of the concentrated liquid product and releasing it into the exiting liquid stream flow path steadily throughout the operating cycle as illustrated in FIG. 35 a where the concentration of the milk measured as a percentage of the total solids present is shown during an operating cycle of approximately 15 seconds. Line a illustrates the concentration profile with the bowl 100 whilst line b illustrates a cartridge without the bowl 100 . As can be seen the concentration profile with the cup 100 is more even during the operating cycle and there is no immediate large drop in concentration as occurs without the bowl 100 . The initial concentration of the milk is typically 30-35% SS and at the end of the cycle 10% SS. This results in a dilution ratio of around 3 to 1, although dilution ratios of between 1 to 1 and 6 to 1 are possible with the present invention. For other liquid beverage ingredients the concentrations may vary. For example for liquid chocolate the initial concentration is approximately 67% SS and at the end of the cycle 12-15% SS. This results in a dilution ratio (ratio of aqueous medium to beverage ingredient in dispensed beverage) of around 5 to 1, although dilution ratios of between 2 to 1 and 10 to 1 are possible with the present invention. For liquid coffee the initial concentration is between 40-67% and the concentration at the end of dispense 1-2% SS. This results in a dilution ratio of between 20 to 1 and 70 to 1, although dilution ratios of between 10 to 1 and 100 to 1 are possible with the present invention.
From the annular channel 86 the beverage is forced under pressure through the aperture 128 by the back pressure of beverage collecting in the filtration chamber 134 and chamber 90 . The beverage is thus forced through aperture 128 as a jet and into an expansion chamber formed by the upper end of the discharge spout 43 . As shown in FIG. 34 , the jet of beverage passes directly over the air inlet 71 . As the beverage enters the discharge spout 43 the pressure of the beverage jet drops. As a result air is entrained into the beverage stream in the form of a multitude of small air bubbles as the air is drawn up through the air inlet 71 . The jet of beverage issuing from the aperture 128 is funnelled downwards to the outlet 44 where the beverage is discharged into a receptacle such as a cup where the air bubbles form the desired frothy appearance.
Advantageously, the inner member 3 , outer member 2 , laminate 5 and filter 4 can all be readily sterilised due to the components being separable and not individually comprising tortuous passageways or narrow crevices. Rather, it is only after conjoining the components, after sterilisation, that the necessary passageways are formed. This is particularly important where the beverage ingredient is a dairy-based product such as liquid milk concentrate.
The fourth embodiment of beverage cartridge is particularly advantageous for dispensing a concentrated dairy-based liquid product such as liquid milk. Previously, powdered milk products have been provided in the form of sachets for adding to a pre-prepared beverage. However, for a cappuccino-style beverage it is necessary to foam the milk. This has been achieved previously by passing steam through a liquid milk product. However this necessitates the provision of a steam supply which increases the cost and complexity of the machine used to dispense the beverage. The use of steam also increases the risk of injury during operation of the cartridge. Accordingly the present invention provides for a beverage cartridge having a concentrated dairy-based liquid product therein. It has been found that by concentrating the milk product a greater amount of foam can be produced for a particular volume of milk when compared to fresh or UHT milk. This reduces the size required for the milk cartridge. Fresh semi-skimmed milk contains approximately 1.6% fat and 10% total solids. The concentrated liquid milk preparations of the present invention contain between 0.1 and 12% fat and 25 to 40% total solids. In a typical example, the preparation contains 4% fat and 30% total solids. The concentrated milk preparations are suitable for foaming using a low pressure preparation machine as will be described below. In particular, foaming of the milk is achieved at pressures below 2 bar, preferably approximately 1.5 bar using the cartridge of the fourth embodiment described above.
The foaming of the concentrated milk is particularly advantageous for beverages such as cappuccinos and milk shakes. Preferably the passing of the milk through the aperture 128 and over the air inlet 71 and the optional use of the bowl 100 enables foaming levels of greater than 40%, preferably greater than 70% for milk. For liquid chocolate foaming levels of greater than 70% are possible. For liquid coffee foaming levels of greater than 70% are possible. The foamability level is measured as the ratio of the volume of the foam produced to the volume of liquid beverage ingredient dispensed. For example, where 138.3 ml of beverage is dispensed, of which 58.3 ml is foam the foamability is measured as [58.3/(138.3-58.3)]*100=72.9%. The foamability of the milk (and other liquid ingredients) is enhanced by the provision of the bowl 100 as can be seen in FIG. 35 b . The foamability of the milk dispensed with the bowl 100 present (line a) is greater than that of milk dispensed without the bowl present (line b). This is because the foamability of the milk is positively correlated to the concentration of the milk and as shown in FIG. 35 a the bowl 100 maintains a higher concentration of the milk a larger part of the operating cycle. It is also known that foamability of the milk is positively correlated to temperature of the aqueous medium as shown in FIG. 35 c . Thus the bowl 100 is advantageous since more of the milk remains in the cartridge until near the end of the operating cycle when the aqueous medium is at its hottest. This again improves foamability.
The cartridge of the fourth embodiment is also advantageous in dispensing liquid coffee products.
It has been found that the embodiments of beverage cartridge of the present invention advantageously provide an improved consistency of the brewed beverage when compared to prior art cartridges. Reference is made to Table 1 below which shows the results of brew yields for twenty samples each of cartridges A and B containing roast and ground coffee. Cartridge A is a beverage cartridge according to the first embodiment of the present invention. Cartridge B is a prior art beverage cartridge as described in the applicant's document WO01/58786. The refractive index of the brewed beverage is measured in Brix units and converted to a percentage of soluble solids (% SS) using standard tables and formulae. In the examples below:
% SS= 0.7774*(Brix value)+0.0569.
% Yield=(% SS *Brew Volume ( g ))/(100*Coffee Weight ( g ))
TABLE 1
Brew
Sample
Volume (g)
Coffee Weight (g)
Brix
% SS (*)
% Yield
CARTRIDGE A
1
105.6
6.5
1.58
1.29
20.88
2
104.24
6.5
1.64
1.33
21.36
3
100.95
6.5
1.67
1.36
21.05
4
102.23
6.5
1.71
1.39
21.80
5
100.49
6.5
1.73
1.40
21.67
6
107.54
6.5
1.59
1.29
21.39
7
102.70
6.5
1.67
1.36
21.41
8
97.77
6.5
1.86
1.50
22.61
9
97.82
6.5
1.7
1.38
20.75
10
97.83
6.5
1.67
1.36
20.40
11
97.6
6.5
1.78
1.44
21.63
12
106.64
6.5
1.61
1.31
21.47
13
99.26
6.5
1.54
1.25
19.15
14
97.29
6.5
1.59
1.29
19.35
15
101.54
6.5
1.51
1.23
19.23
16
104.23
6.5
1.61
1.31
20.98
17
97.5
6.5
1.73
1.40
21.03
18
100.83
6.5
1.68
1.36
21.14
19
101.67
6.5
1.67
1.36
21.20
20
101.32
6.5
1.68
1.36
21.24
AVERAGE
20.99
CARTRIDGE B
1
100.65
6.5
1.87
1.511
23.39
2
95.85
6.5
1.86
1.503
22.16
3
98.4
6.5
1.8
1.456
22.04
4
92.43
6.5
2.3
1.845
26.23
5
100.26
6.5
1.72
1.394
21.50
6
98.05
6.5
2.05
1.651
24.90
7
99.49
6.5
1.96
1.581
24.19
8
95.62
6.5
2.3
1.845
27.14
9
94.28
6.5
2.17
1.744
25.29
10
96.13
6.5
1.72
1.394
20.62
11
96.86
6.5
1.81
1.464
21.82
12
94.03
6.5
2.2
1.767
25.56
13
96.28
6.5
1.78
1.441
21.34
14
95.85
6.5
1.95
1.573
23.19
15
95.36
6.5
1.88
1.518
22.28
16
92.73
6.5
1.89
1.526
21.77
17
88
6.5
1.59
1.293
17.50
18
93.5
6.5
2.08
1.674
24.08
19
100.88
6.5
1.75
1.417
22.00
20
84.77
6.5
2.37
1.899
24.77
AVERAGE
23.09
Performing a t-test statistical analysis on the above data gives the following results:
TABLE 2
t-Test: Two-Sample Assuming Equal Variances
% Yield
% Yield
(Cartridge A)
(Cartridge B)
Mean
20.99
23.09
Variance
0.77
5.04
Observations
20
20
Pooled Variance
2.90
Hypothesized Mean Difference
0
df
38
t Stat
−3.90
P(T <= t) one-tail
0.000188
t Critical one-tail
1.686
P(T <= t) two-tail
0.000376
t Critical two-tail
2.0244
Standard Deviation
0.876
2.245
The analysis shows that the consistency of % yield, which equates to brew strength, for the cartridges of the present invention is significantly better (at a 95% confidence level) than the prior art cartridges, with a standard deviation of 0.88% compared to 2.24%. This means that beverages brewed with the cartridges of the present invention have a more repeatable and uniform strength. This is preferred by consumers who like their drinks to taste the same time after time and do not want arbitrary changes in brew strength.
The materials of the cartridges described above may be provided with a barrier coating to improve their resistance to oxygen and/or moisture and/or other contaminant ingress. The barrier coating may also improve the resistance to leakage of the beverage ingredients from within the cartridges and/or reduce the degree of leaching of extractibles from the cartridge materials which might adversely affect the beverage ingredients. The barrier coating may be of a material selected from the group of PET, Polyamide, EVOH, PVDC or a metallised material. The barrier coating may be applied by a number of mechanisms including but not limited to vapour deposition, vacuum deposition, plasma coating, co-extrusion, in-mould labelling and two/multi-stage moulding. | A cartridge containing one or more liquid beverage ingredients and being formed from substantially air- and water-impermeable materials, the cartridge comprising an inlet for the introduction of an aqueous medium into the cartridge, a compartment containing the one or more liquid beverage ingredients and an outlet for a beverage produced by dilution of the one or more liquid beverage ingredients by the aqueous medium, characterised in that the compartment includes means for controlling dilution of at least a proportion of the one or more liquid beverage ingredients on introduction of the aqueous medium into the compartment. | 0 |
[0001] This application claims priority of PCT application PCT/EP2005/012538 having a priority date of Nov. 23, 2005, the disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The invention concerns a rail for a self-propelled electric trolley.
BACKGROUND OF THE INVENTION
[0003] Rails of the type mentioned above are known from many examples.
[0004] CH 515 819 describes such a rail in which the C-shaped sides of the rails engage the side wheels of the trolley. The wheels in turn run on the upper or lower edges of the C-shaped sides. For lateral support, radially projecting support rims, which function in concert with the side parts of the sides of the rail, are provided along the circumferential running surfaces of the trolley wheels on the side facing away from the sides. Because they can be easily damaged, the support rims make the trolley wheels relatively complicated and vulnerable. The support rims may also cause damage to a surface on which the trolley is placed outside the rail. Finally, the rail is also relatively complicated, because it requires a ledge on which the support rims can be supported laterally to be present between the sides and the base part of the rail. In overhead suspension operation, the support rim exerts force on the outer edge of the sides, making it necessary for these parts to be of thick construction to prevent bending. They therefore require a relatively high amount of material and are thus costly.
[0005] WO95/14599 presents an improved rail in which the C-shaped sides connect evenly to the base part and no ledges are necessary. For the trolley wheels, the support rims are replaced by lateral guide wheels within the wheels, which abut the center of the sides. Because the guide wheels engage the center of the sides, less supporting force needs to be exerted by the sides and the rails can therefore be of lighter construction as a result of the supporting forces acting at a lower level. However, this rail may only be used by trolleys with lateral guide rollers.
SUMMARY OF THE INVENTION
[0006] The object of the invention is to create a novel type of rail, which allows mixed operation of trolleys with and without lateral guiding rollers.
[0007] If each C-shaped side features a central, outwardly displaced running area for the lateral guide rollers of the trolley and upper and lower support surfaces for the side wheel inclined towards the wheel, where the running areas and the support surfaces areas are used in alternation, then the rail can be used by both trolleys with simple wheels without support rims and by trolleys with lateral guide rollers. The simple wheels rest on the lower support surfaces when the trolley is driven on a normal level, or on the upper support surfaces when the trolley is driven suspended overhead. On trolleys with lateral guide rollers, these rollers abut the middle running area of the C-shaped sides of the rails. The novel rail thus facilitates mixed operation by both types of vehicles.
[0008] The special profiling of the C-shaped sides of the rails reduces the bending of the sides when overhead suspension is employed. Less material is required to construct the rail, while at the same time the trolley can be loaded more heavily. The space gained through the upper guide bevel of the side can be used for integrating the assembly grooves.
[0009] Advantageous configurations of the rails are detailed in the following exemplary embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The exemplary embodiments of the invention are described in greater detail with reference to the drawings, wherein:
[0011] FIG. 1 A rail with a trolley without lateral guide rollers, frontal view;
[0012] FIG. 2 A rail with a trolley with lateral guide rollers, frontal view
[0013] FIG. 3 The rail shown in FIGS. 1 and 2 without trolley;
[0014] FIG. 4 Diagrammatic illustration of the rail shown in FIG. 3 ;
[0015] FIG. 5 Side view of the connection between two rail segments;
[0016] FIG. 6 Side view of the connection between two rail segments with expansion joint;
[0017] FIG. 7 The rail shown in FIG. 3 only with power rails;
[0018] FIG. 8 The rail shown in FIG. 7 in section VIII-VIII from FIG. 7 ;
[0019] FIG. 9 The rail shown in FIG. 7 in section IX-IX from FIG. 7 ;
[0020] FIG. 10 Diagrammatic illustration of a concave rail segment;
[0021] FIG. 11 Diagrammatic illustration of a convex rail segment;
[0022] FIG. 12 Diagrammatic illustration of a laterally curved rail segment;
[0023] FIG. 13 A base segment part for connecting the sides of the rail shown in FIG. 12 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] FIGS. 1 and 2 show a cross section of a segment of a conveyor system that features rails 2 in which a self-propelled trolley 4 is arranged. One such rail 2 features a base part 6 and C-shaped sides 8 , 10 , which enclose the side wheels 12 of the trolley 4 . The C-shaped sides 8 , 10 each feature a central, outwardly displaced running area 14 for the lateral guide rollers 16 of the trolley, as well as upper and lower support surfaces 18 , 20 , each inclined towards the wheel 12 . One and the same rail is thus suited for trolleys 4 that feature lateral guide rollers 16 , as shown in FIG. 2 , and for trolleys 4 without lateral guide rollers, but on which the wheels 12 simply abut the support surfaces 18 , 20 .
[0025] The wheels 12 and the guide rollers 16 are generally non-powered wheels or rollers without any drive function. Drive is provided on the one hand by a frictional wheel 22 functioning in concert with a corresponding frictional surface 24 of the rail 2 , and/or a cog 26 functioning together with a cog rail 28 of the rail 2 . Sliding contacts 30 , 32 , 34 function together with power rails 36 , 38 , 40 in the rail and serve to transmit current on the one hand and provide switching and control functions on the other hand.
[0026] The details of the rail and its function are illustrated in greater detail in FIGS. 3 through 13 and are further described below.
[0027] In the respective upper portion of the C-shaped sides 8 , 10 , the rail 2 features dovetailed assembly grooves 42 , 44 , which accommodate the clampable connection strips 46 for connecting adjoining rail segments 2 a , 2 b to one another. Additional assembly grooves 48 , 50 for accommodating connection strips 46 are arranged on the bottom side of the base part 6 of the rail 2 . To provide a secure connection between adjoining rail sections 2 a , 2 b , the connection strips 46 feature clamping screws 52 for each rail section 2 a , 2 b as FIG. 5 illustrates. To create an expansion joint 54 between segments 2 a , 2 b , the connection strips 46 are fastened to only one rail segment 2 b by means of clamping screws 52 , while the connection strip 46 is displaceably arranged in the other rail segment 2 a as FIG. 6 shows.
[0028] The power rails 36 , 38 , 40 are fastened with the aid of sliders 56 , which feature a block part 58 with molded feet 60 , 62 , which engage the dovetailed assembly grooves 64 of the rails 2 . Driven dowel pins 66 between the feet 60 , 62 prevent the sliders 56 from separating from the base part 6 . In FIGS. 7 and 9 , the dowel pins 66 are shown prior to being driven into the opening 68 between the feet 60 , 62 . Recesses 70 for accommodating the power rails 36 , 38 , 40 are arranged in the block part 58 . Lateral to the block part 58 are snap-in pins 72 , which feature snap-in hooks 74 , 76 oriented away from one another, which function together with facing snap-in strips 78 , 80 of the hollow power rails 36 , 38 , 40 . To facilitate connection to a power supply, the heads 82 of contact screws 84 extending through the block part 58 of the slider 56 and the base part 6 of the rail 2 to the opposite side thereof are arranged in the power rails 36 , 38 , 40 . As FIGS. 1 through 3 reflect, the contact screws 84 are secured by means of a first nut 86 , while a second nut 88 serves for clamping the power supply connection 90 .
[0029] Arranged on the bottom side of the base part 6 is an additional dovetailed assembly groove 92 for the purpose of fastening cable clips 94 . The latter features clipping feet 96 , 98 , which engage the assembly groove 92 and between which a dowel pin 100 is arranged to prevent the feet from separating from the assembly groove 92 . The cable clips 94 arranged at specific intervals on the bottom side of the base part 6 serve to hold all types of lines such as power supply lines and control lines. The bottom side of the base part 6 can also ultimately be covered with a cover 102 that features side fastening strips 104 , 106 that engage corresponding insert grooves 108 , 110 on the bottom side of the base part.
[0030] An additional dovetailed assembly groove 112 for securing the cog rail 28 is arranged on the top side of the base part 6 .
[0031] A rail of this kind can be bent to form an inside curve as shown in FIG. 10 or an outside curve as shown in FIG. 11 . For this purpose, the rail can be bent as a whole unit in the manner shown.
[0032] To form an inside or outside curve as shown in FIG. 12 , the C-shaped sides 8 a and 10 a must be individually bent according to the desired curvature radius and then connected to one another using the base segment parts 6 a.
[0033] The new rail is suited not only for mixed operation by trolleys with and without lateral guide rollers, but, thanks to the assembly grooves and the insert-and-clip connections, can be employed universally, is easy to retrofit, and can be assembled quickly and easily. Rails can be removed and later reused in a simple manner. No complicated tools are required.
[0000]
Reference number list
2
Rail
2a, 2b
Rail segment
4
Trolley
6
Base part
6a
Base segment part
8, 8a
C-shaped side
10, 10a
C-shaped side
12
Wheel
14
Running area
16
Guide roller
18, 20
Support surface
22
Frictional wheel
24
Frictional surface
26
Cog
28
Cog rail
30, 32, 34
Sliding contact
36, 38, 40
Power rail
42
Assembly groove on 8
44
Assembly groove on 10
46
Connection strip
48
Assembly groove on 6
50
Assembly groove on 6
52
Clamping screw
54
Expansion joint
56
Slider
58
Block part
60, 62
Foot
64
Assembly groove
66
Dowel pin
68
Opening
70
Recess
72
Snap-in pin
74, 76
Snap-in hook
78, 80
Snap-in strip
82
Head
84
Contact screw
86
First nut
88
Second nut
90
Power supply connection
92
Assembly groove
94
Cable clip
96, 98
Foot
100
Dowel pin
102
Cover
104, 106
Fastening strip
108, 110
Insert groove
112
Assembly groove for 28 | Rail for self-propelled electric trucks, with the rail ( 2 ) having a base part ( 6 ) and C-shaped side flanks ( 8, 10 ) which engage over side wheels ( 12 ) of the truck ( 4 ). In order to improve the rail, each C-shaped side flank ( 8, 10 ) has a central running area ( 14 ), which is offset outwards, for side guide rollers ( 16 ) of the truck ( 4 ) and upper and lower supporting services ( 18, 20 ) which run at an angle to the wheel ( 12 ) for the side wheels ( 12 ), with the running area ( 14 ) and the supporting areas ( 18, 20 ) being used alternately. | 4 |
This application is a divisional application of and claims priority to U.S. patent application Ser. No. 09/088,624, filed Jun. 2, 1998.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to the field of information services and, more particularly, to automated toll-free information services and apparatus used for performing such services where, for example, in the United States, there exist certain toll-free “area codes” or prefixes for identifying a toll-free call such as 1-800 and 1-888 and wherein such automated toll-free information services may comprise an Internet link to an information services database.
2. Description of the Related Arts
Information services are well known. A caller, desirous of receiving a telephone number for a listing, typically dials an abbreviated telephone number such as 411 or, for long distance, an area code followed by a standard 555-1212 telephone number in the United States for receiving directory assistance. For 1-800 and 1-888 listings of toll-free numbers, consumers can obtain directory assistance in such a simplified manner but are limited to one toll-free number per call. (Recently in the United States, AT&T announced the introduction of an additional 1-877 toll-free service.) The user of toll-free information services calls 1-800-555-1212 and is greeted by AT&T operator services and may receive, for example, a 1-800 toll-free number for a hotel chain reservation number. Many toll-free numbers, typically for businesses, may be found in the Yellow Pages (R) information section of a telephone directory and also are listed in a special toll-free telephone directory which may be obtained for a fee.
Information services are now automated to a great extent. When a caller dials directory assistance, the caller is typically greeted by a voice response unit which requests “For what city please” and a name of a desired listing from the caller. In many instances, the caller may receive a synthesized voice response providing the directory listing. In other instances, the caller may be referred to a live operator at an information service position who may manually assist the caller to receive the synthesized voice response.
Despite the progress toward further automation of directory assistance and information services, there continues a further need to make the process as thoroughly automated as possible and, moreover, provide specialized nationwide assistance to callers requesting toll-free telephone number and other information assistance.
In U.S. patent application Ser. No. 08/635,801, filed Apr. 22, 1996, entitled “Method and Apparatus for Information Retrieval Using Audio Interface” of Benedikt et al., there is generally described a network-based information retrieval service for retrieving text-to-voice (TCP/IP to conventional telecommunications) conversion via an interpreter. The interpreter interprets a document into audio data which is provided to an audio user interface. Such an audio browsing adjunct forms an apparatus basis for the present service and apparatus and its disclosure is incorporated by reference herein as to its entire contents.
Also, in U.S. application Ser. No. 08/991,437, filed Dec. 16, 1997, entitled “Method and Apparatus for Providing Telephone Network Based Conversant Services” of Aris A. Yiannoulos, there is described an enhancement of the Benedikt et al system for providing network-based voice interactive services. The user of that invention does not need to provide voice interactive systems on their premises. The user, typically a business customer, may share a network-based voice interactive system with other users. For example, a business may have a toll-free number for allowing employees to retrieve employee savings plan information. The network-based information system provides such information to the employee who calls requesting such information in the same manner as if the voice interactive system were on the employer's premises.
Yet there remains a need in the art for a specialized, automated toll-free information service and apparatus for providing automated information services to callers in need of a toll-free directory listing. Moreover, the system should be flexible enough to permit matching of a plurality of choices of toll-free listings which may be responsive to a general query, for example, for a category of listings.
SUMMARY OF THE INVENTION
In the field of toll-free information services and in accordance with the present invention, a network-based server is provided of the type generally described by Benedikt et al. Such a network based service and apparatus may have a unique telecommunications network listing such as 1-800-FIND-4-ME. The user interested in using this service will dial this directory listing and receive toll-free service (there would be no charge for the call). On the other hand, those that subscribe to a toll-free telephone directory may also wish to have their listing made available also over the 1-800-FIND-4-ME service. These customers, typically, business customers, may be provided the service of the present invention for free as a value-added benefit for having subscribed to the toll-free directory or, in the alternative, be asked to pay for such a listing. In either manner, the service may be provided for free to the caller.
According to the present invention, once the caller dials the toll-free 1-800-FIND-4-ME number, the call is routed via a toll switch in a well known manner to a server such as that described by the Benedikt et al. application. An announcement will play such as “Welcome to the toll-free search service. Please give me the category or type of information you request.” The caller will be asked to identify a category of interest to the user such as “clothing catalog services” or “bicycling catalogs.” In response, a voice interactive system will ask the caller to verify that the listing or information is truly what the caller wishes by repeating the request. In this manner, the caller may verify the request has been accurately interpreted and signify the same by saying “Yes.”
Once the request is verified, the voice interactive system initiates a search which may be via the Internet or telecommunications data links to a, preferably, centralized database. The search may return a single response or a plurality of possible responses to the request for a category of listings. If the search of the database is by TCP/IP Internet links, the database may return audio clip packets representing the various matches to the request or the database may return data representing the matches. If the database search is requested by telecommunications data links, the links may be medium speed or baud rate or even lower speed on a bandwidth-on-demand basis, for example, via out-of-band signaling systems such as SS7.
Upon receipt at the server of the data responsive to the query, a response to the user is provided by the network-based voice interactive system such as: “There are five matches to your information request. Would you like to hear about them?” Upon a yes reply by the caller, the voice interactive system may announce: “We will scroll through the entries and play a brief recording introducing the company to you. You may directly connect to the company by pressing the 1 key or skip to the next entry by pressing the pound # key. You may also go back to any point by repeatedly pressing the star * key or by pressing the entry number followed by the pound #key.”
According to principles described in copending U.S. application Ser. No. 09/005,256, filed Jan. 9, 1998, for “Method and Apparatus for an Automated Barge-In System” of Steve Salimando, incorporated by reference as to its entire contents, the caller may interrupt at any time during the process and connect to a business listing or even hang up. The user may do so by pressing a key as suggested above, or, in accordance with the '256 application, say the words “Please dial” and be automatically connected to the destination.
A further feature of the present invention is the opportunity to announce the toll-free telephone number to the caller before launching the call to the number and providing the caller with the opportunity to write down or otherwise record it. If the caller does not wish to automatically launch a call to that listing, the caller may simply hang-up. Finally, another feature of the present invention is that the automated toll-free information service may be implemented via a voice call or via the Internet and E-Mail.
These and other features of the present invention will become clear to one of ordinary skill in the art from the following detailed description of the invention and associated drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 provides an overall system block diagram for describing the network architecture of the present invention and, in particular, the operation of the service node 190 of the present invention.
FIG. 2 comprises a functional block schematic diagram of a service node 190 of the present invention for providing automated toll-free telecommunications information services.
FIG. 3 provides an overall flowchart for describing an algorithm for implementing the present toll-free information service at the service node 190 of FIG. 1 .
DETAILED DESCRIPTION
Referring now to FIG. 1, the reference numerals between 1 and 10 relate to steps in a calling process and appear adjacent to network elements performing the steps or to the links connecting network elements. The elements of a telecommunications network including a service node according to the present invention are given reference numerals between 100 and 190 . The apparatus for providing an automated toll-free telecommunications information service is most conveniently located in association with service node 190 which may comprise a telecommunications adjunct processor, for example, such as the apparatus described in the application to Benedikt et al. referred to above. In an alternative embodiment, the service node 190 may comprise a portion of or be directly associated with toll switch 120 . The surrounding network comprises a caller terminal 100 , a local exchange carrier (LEC) 110 , the toll switch 120 , such as a #4 ESS toll switch, manufactured by Lucent Technologies, Inc., and an associated database 130 for dialed address or number (DN) to routing translation. Besides the service node 190 , also shown are a typical business customer 150 employing the present service and an information database 140 . Network elements 120 , 130 , 190 and 140 are included within the boundaries of a toll network cloud 160 . The business customer 150 may be within the service boundary of the LEC 110 or without its boundary. Similarly, the caller 100 may be in the same LATA as the business customer or outside it. One feature of the present invention as will be described herein is to provide a centralized toll-free information service for any business customer 150 located anywhere in the country so that caller 100 may similarly be located anywhere within the country but learn about the existence of such a business customer and be connected to that business customer through the service node of the present invention.
Referring to FIG. 2, there is shown a functional block schematic diagram of a service node 190 which may perform the automated information service of the present invention. Typically, the service node may comprise a nation-wide resource when performing the present service to which calls may be routed by any toll switch 120 or LEC 110 . The service node 190 , shown in greater detail in FIG. 2, more particularly comprises speech recognition circuits 220 for recognizing speech of a caller and providing the speech data to a controller/processor 210 for processing. In the alternative, or in addition, the service node 190 comprises tone detection circuitry 230 for recognizing dialed multi-frequency tone signals indicative according to well known telephone dialing keypads of numerals or groups of three alphabetic letters. The service node 190 may comprise a Conversant (TM) system available from Lucent Technologies, Inc. or other speech recognition and voice response systems known in the art having call processing capability as well.
Data input to data processor/controller 210 then may come from toll switch 120 (the caller), from information database 140 , from speech recognition circuits 220 or from tone detection circuits 230 . Programs/algorithms and temporary memory for formulating queries and responses to callers is shown as program/data memory 250 . For example, an algorithm for the present invention is shown in flowchart form in FIG. 3 . Software representing that or an equivalent flowchart may be resident in memory 250 .
Speech synthesis circuitry 240 formulates queries and responses for a caller at terminal 100 responsive to the controller 210 operating the program of the present invention stored in program memory 250 . Speech synthesis circuitry 240 may translate TCP/IP audio clip packets to analog voice signals or translate data signals to voice for delivery to caller 100 . This is one output function of the service node 190 according to the present invention. One further output function is that controller 210 may process a caller response and undertake the launching of a call to business customer 150 . To that end the controller 210 signals the toll switch 120 with the business customer's identification once the caller 100 selects the option of initiating a call to be launched. These and other input and output functions of service node 190 will now be more fully described with reference to FIGS. 1 and 3.
In particular, a typical caller has station apparatus 100 which may comprise a typical telephone station set, a feature set, a vision phone, a personal computer, intelligent web telephone or other apparatus. The caller places a call to a telephone number such as 1-800-FIND-4-ME. This number is exemplary only and may be otherwise suitably chosen for the service. This step is shown as step 1 in FIG. 1 . Typically, the caller places the call by going off hook, receiving dial tone from LEC 110 and actuating the corresponding alphanumeric keys of their touch tone keypad. This step corresponds also to box 305 of FIG. 3 .
LEC 110 recognizes that the 1-800-FIND-4-ME telephone number is not within its control, is rather within a toll carrier's control such as AT&T and forwards the call and associated dialed number (DN) data to toll switch 120 . Toll switch 120 may be referred to as a switch control point (SCP). SCP 120 forwards the dialed number (DN, the dialed 800 number) to database 130 at a network control point for routing translation. This step is shown as step 2 in FIG. 1 .
The network control point (NCP) refers to database 130 and obtains routing information for the 1-800-FIND-4-ME number for routing the call to the appropriate service node 190 . The routing information includes the platform address of the server of service node 190 . This step is shown as step 3 in FIG. 1 . Once the toll switch 120 , where the call has been temporarily parked, receives the routing information, the toll switch routes the call from caller 100 to service node 190 . This step is shown as step 4 in FIG. 1 and box 310 in FIG. 3 .
Service node 190 receives the call and a link between the caller 100 and the voice response system of FIG. 2 is now complete. Now the service node plays an announcement at step 315 of FIG. 3 . One typical announcement to welcome the caller to the toll-free information service might be: “Welcome to the toll-free search engine. Please give me the category of your interests?” Now the caller 100 may respond in any way the caller wishes. The caller may say “antique auction houses”. The caller may say “hotels in Denver, Colo.”. This step is shown as box 320 of FIG. 3 . Let us assume that the caller requests the category “bicycling catalogs.” The speech recognition circuitry 220 of the service node 190 of FIG. 2 collects the response and provides output data to the controller 210 . The controller 210 identifies the request as best it can at box 325 of FIG. 3 . The controller 210 formulates a verification query from the data it has received. For example, the voice response unit may output data to speech synthesis circuitry 240 to say: “You have asked for bicycling catalogs; if that is the category you are seeking please say—yes—or push one on your keypad now.” If the answer is by speech, then speech recognition circuit 220 collects the response; if by tone keypad, then tone detection circuit 230 collects the response. In either event of a yes response, the search engine of the controller 210 will attempt to utilize its own or alternative databases to establish as many matches as possible with the category.
The announcement for verification may continue and say: “If this is not the category you are seeking, please restate your requested category so that we may understand you.” This iterative process is shown in FIG. 3 as the loop from “request correct” box 335 to play announcement box 315 and then through boxes 320 , 325 , 330 , 340 and 335 until the request is correctly interpreted.
Continuing with a correct interpretation of the request, controller 210 looks for bicycling catalogs via an Internet or other data link to as many databases as appropriate. Of course, it is most desirable if only one centralized database 140 is needed. Nevertheless, it may be within the boundaries of the present invention to call upon distributed databases 140 via an Internet or telecommunications data query. This step is shown as step 5 on FIG. 1 . In accordance with the present invention, the data on a particular match may include the identity of the business customer, the toll-free telephone number and a brief (for example, fifteen-second)) description of the business customer and services. The data may be returned as audio clip data in TCP/IP protocol or other data format. The data then may be translated to a synthesized speech announcement or simply played as received from the database.
The return of matches from database 140 or other databases 140 is shown as step 6 in FIG. 1 . Whether one or multiple databases return matches, controller 210 counts the number of matches and announces them to the user. The announcement of the number and identities of choices is shown as step 345 of FIG. 3 .
Continuing the example where the caller 100 has requested bicycling catalogs, the announcement may be as follows: “We have found five matches for your category of bicycling catalogs. Would you like to hear about them?” The caller in all likelihood will respond—yes—and the announcement may continue: “We will scroll through all five entries and then play a fifteen-second recording introducing each match. You may connect to our business customer at their toll-free number by pressing the one key or skip to the next entry by pressing the pound key #. You may also go back to any point in the list by pressing the star key * and the entry number followed by the pound key #.” Of course, this type of announcement and way of introducing the list of matches is just one way to do so. Other ways may be obvious therefrom such as pressing the star key * multiple times to move backwards or the pound key # multiple times to move forward as many matches as key depressions.
One way a caller 100 may signify which entry may be of interest is via a barge-in. For example, the user may wish to barge in after hearing about a particular entry such as Mountain Bikes of Denver, Colo. Barge-in is further described by U.S. patent application Ser. No. 09/005,256, filed Jan. 9, 1998, and incorporated herein by reference. The user simply says—yes—to a particular match such as Mountain Bikes and the announcement VRU may continue as follows: “The toll-free number for Mountain Bikes of Denver, Colo. is 1-800-MTBIKES. We will dial it now for you if you say—Please dial.” Barge-in and making a choice are shown as steps 350 and 355 . Once the command “please dial” is interpreted, the controller may initiate control signals for launching a call to Mountain Bikes at step 360 . The new dialed number (DN) for mountain bikes is signaled to toll switch 120 , the switch control point (SCP), at step 7 of FIG. 1. A DN to routing translation is done according to a well known manner at steps 8 and 9 by looking up the dialed number in database 130 of a network control point (NCP) and returning the routing information to toll switch 120 . Finally at step 10 of FIG. 1, the call is completed to Mountain Bikes, the exemplary business customer 150 whom the caller 100 has selected.
There exist obvious variations on the present invention. In one embodiment, the user may receive all the telephone numbers of all the matches by voice. The caller 100 may request that they be transmitted by E-Mail to their corresponding E-Mail address. The user may request that the bicycling catalog itself be transmitted to their E-Mail address where the user may print the catalog out themselves using their personal computer and printer.
In an alternative embodiment, the caller may make an E-Mail request of the present toll-free information service and receive voice responses. The Internet service provider of such a toll-free information service may collect the automatic number identification (ANI) data corresponding to the telephone number of the caller requesting service and forward that address to the service node. The service node may initiate a call to the caller 100 based on the ANI data and upon having completed an analysis of the E-Mail request for toll-free information and announce to the caller the number of matches and so on following steps 335 to 365 from FIG. 3 as the caller desires.
Other modifications of the present invention may come to mind of one of ordinary skill in the art. All patent applications identified herein should be deemed to be incorporated by reference as to their entire contents. The present invention should only be deemed to be limited in scope by the claims which follow. | An automated toll-free telecommunications information service may be provided responsive to a user sending an E-Mail request via the Internet or by a caller dialing a toll-free telephone number and announcing a voice request. A service node interprets the request and collects matches to the request from a database. A match to a request may comprise the identity of an entity corresponding to the match, a toll-free number for the match and a brief information sketch describing the entity. The matches are announced and played for the caller. The caller may barge in with a predetermined voice announcement such as “please dial” when they wish to select an item of the list. In response, the service node initiates the launch of a call to the selected entity. | 7 |
FIELD OF THE INVENTION
[0001] This application claims priority from German Patent application No. 10 2005 045 717.7 filed Sep. 24, 2005, incorporated herein by reference in its entirety.
[0002] The invention relates to a substrate carrier.
BACKGROUND AND SUMMARY OF THE INVENTION
[0003] Substrates are often guided in sputter units past a so-called target, from the surface of which particles are sputtered off, which are subsequently deposited on the substrate. As the substrates can be utilized, for example, glass plates, which are transported through an inline sputter unit. These glass plates are set into a frame connected with a transport device.
[0004] A device for the transport of substrates into and through vacuum treatment units, for example, is known, which comprises a bulky foot part composed of two wheel sets correlated with one track and one support bearing (DE 41 39 549 A1). The substrates to be treated are herein held by means of a rectangular substrate holder.
[0005] Furthermore is known an annular substrate holder for the mounting of a round substrate plate, this substrate holder, in turn, being held by four equally distributed holding arms (DE 102 11 827 C1).
[0006] If the substrates held in frames have a coefficient of thermal expansion different from that of the frames, the substrates may be covered at the margins nonuniformly and onesidedly to too high a degree. In the case of wafers this is referred to as “edge exclusion”, i.e. to a peripheral region of the wafer which is not coated.
[0007] The invention therefore addresses the problem of providing a carrier for substrates, in which the substrate are not covered too thickly at the margin and the coverage on both margins is substantially equal.
[0008] This problem is solved according to the present invention, which relates in part to a carrier for a substrate comprising two vertical plates and two horizontal plates. In order for the substrate not to be coated nonuniformly in its margin regions during its transport through a sputter unit, a lever arrangement is provided between the two vertical plates. The lever arrangement comprises at least one horizontal web which expands to a lesser degree under the effect of heat than the horizontal plates.
[0009] The advantage attained with the invention resides in particular therein that with the aid of a lever arrangement, which exploits the effect of the difference in the coefficients of thermal expansion, the substrates to be coated are held symmetrically relative to the carrier frame.
[0010] An embodiment example of the invention is shown in the drawing and will be described in further detail below.
BRIEF DESCRIPTION OF THE FIGURES
[0011] FIG. 1 shows a first embodiment of the invention.
[0012] FIG. 2 shows a second embodiment of the invention.
DETAILED DESCRIPTION
[0013] FIG. 1 depicts a carrier 1 for a substrate 2 , which comprises a frame with two vertical plates 3 , 4 and two horizontal plates 5 , 6 . The plates 3 , 4 are comprised, for example, of titanium, while the plates 5 , 6 are comprised, for example, of aluminum.
[0014] The left end of the upper aluminum plate 5 is connected with the titanium plate 3 by means of bolts 7 , 8 , 9 or other connection elements.
[0015] The right end of the aluminum plate 5 is not directly connected with the titanium plate 4 but rather indirectly via a small aluminum plate 10 . This small aluminum plate 10 is connected with its right end by means of three bolts 11 , 12 , 13 or the like with the titanium plate 4 . At ambient temperature there is a gap between the plate 4 and the aluminum plates 5 , 6 , which is closed at sputter temperatures. Consequently, FIG. 1 shows a carrier during sputter operation.
[0016] By means of a bolt 14 or the like approximately in the center of the small aluminum plate 10 a rotatable connection is established between the small aluminum plate 10 and the right end of a web 15 of titanium. Instead of a bolt 14 , a pin, stud or the like can be utilized, which holds together two parts and makes possible their relative movement or rotational movement. There is no fixed connection between the small aluminum plate 10 and the large aluminum plate 5 . The aluminum plate 10 is only guided in the aluminum plate 5 . The left end of the titanium web 15 is rotatably connected with the lower end of a perpendicularly extending web 16 by means of a bolt 17 or the like, which does not extend through the aluminum plate 5 . A rotatable connection between this aluminum plate 5 and the upper end of web 16 is established by means of a bolt 18 or the like. The vertical web 16 does not necessarily need to comprise titanium, it can also be produced for example of steel or another metal.
[0017] Via a bolt 19 or the like in the center of vertical web 16 a connection has been established between this web 16 and the right end of a horizontally extending further web 20 , not, however, with plate 5 . The left end of web 20 is directly connected with plate 5 via a bolt 21 or the like. However, a direct connection between plate 3 and web 20 could also be provided.
[0018] Mirror symmetrically to the structural parts located on the upper plate 5 are also disposed the corresponding structural parts on the lower plate. Therefore, bolt 26 corresponds to bolt 14 .
[0019] The small aluminum plates 10 , 25 can each move horizontally on the large aluminum plates 5 , 6 , since they only rest in contact on them or are guided in them.
[0020] With the aid of the lever arrangements formed by webs 15 , 16 , 20 and 27 , 31 , 32 , respectively, it is possible to keep the distance between plates 3 , 4 constant.
[0021] The manner in which this is specifically achieved will be described in the following.
[0022] If it is assumed that the device depicted in FIG. 1 is brought from approximately ambient temperature to a temperature increased by approximately 220° C. as is customary during sputtering, all parts comprised of aluminum expand to a high degree, while the parts comprised of titanium expand to a lesser degree.
[0023] Consequently a relative movement between the individual parts occurs, which essentially results in a relative movement between the small aluminum plates 10 and 25 with respect to the large aluminum plates 5 , 6 . In effect, the small aluminum plates 10 and 25 pull the plate 4 relatively to the left, such that the original distance from plate 3 is maintained.
[0024] With an increase of the temperature the aluminum plates 5 , 6 expand to a high degree. The gaps previously existing between the aluminum plates 5 , 6 and plate 4 are hereby closed. Since the horizontal titanium webs 20 , 32 are connected with the large aluminum plates 5 , 6 in points 21 , 33 , these titanium webs 20 , 32 move with the aluminum plates 5 , 6 to the right. They therewith would rotate the webs 16 , 31 about the pivot points 18 , 30 in the counterclockwise direction or the clockwise direction, which are fixedly connected in these pivot points 18 , 30 with the aluminum plates 5 , 6 , if they were to have a coefficient of thermal expansion corresponding to the coefficients of thermal expansion corresponding to the plates 5 , 6 . Therewith the small aluminum plates 10 , 25 would be pushed away toward the right via the webs 15 , 27 , i.e. they would slide over the large aluminum plates 5 , 6 . However, points 18 and 30 themselves have shifted considerably toward the right, since they are connected with the plates 5 , 6 . Consequently, the web 16 does not rotate in the counterclockwise direction, but rather in the clockwise direction, since point 19 relative to point 18 is retained in position by titanium web 20 , while point 18 migrates toward the right. The displacement of points 30 and 18 to the right is herein approximately three times as large as that of points 29 or 19 , respectively. In contrast, web 20 , 32 , since it is comprised of titanium, has expanded only minimally toward the right and retains points 19 or 29 nearly in their original position.
[0025] As a consequence the upper web 16 is not rotated about point 18 in the counterclockwise direction, but rather in the clockwise direction. The lower web 31 conversely is not rotated about point 30 in the clockwise direction, but rather in the counterclockwise direction.
[0026] The small aluminum plates 10 , 25 are therewith shifted to the left and over plates 5 , 6 . Since they are coupled with plate 4 , the latter is also shifted to the left. Therewith the gap previously formed between plate 4 and the small aluminum plates 10 , 25 is closed. With the appropriate layout of the ratios of the lengths between the points 30 , 29 and 28 , the distance between the titanium plates 3 , 4 can be kept constant.
[0027] FIG. 2 shows a second variant of the invention, which includes a frame 40 for the transport of a substrate 2 . This frame 40 is comprised of two large horizontal aluminum plates 41 , 42 and two vertical titanium plates 43 , 44 . Centrally on the large aluminum plates 41 , 42 are disposed titanium webs 45 , 46 , which are connected with these aluminum plates 41 , 42 by means of connection elements 47 , 48 in their center. These titanium webs 45 , 46 are rotatably connected at their ends with levers 53 to 56 via connection elements 49 to 52 . These levers 53 to 56 are, in turn, rotatably connected with plates 43 or 44 via connection elements 57 to 60 . Ends of the aluminum plates 41 , 42 are also connected with these plates 43 , 44 via connection elements 61 to 70 .
[0028] When the frame 40 is heated during the sputtering, the parts comprised of aluminum expand to a greater degree than the parts comprised of titanium. This means that the aluminum plates 41 , 42 expand horizontally to a greater degree than the titanium plates 43 , 44 or the titanium webs 45 , 46 .
[0029] The levers 53 to 56 are hereby rotated about points 57 to 60 in the direction toward the substrate 2 . On the one hand, the aluminum plates 41 , 42 press plates 43 , 44 apart, on the other hand, the ends of levers 53 to 56 remain in contact on the substrate, since, due to the lesser thermal expansion of webs 45 , 46 , these levers 53 to 56 are in effect retained in their position in their center and must rotate inwardly about points 57 to 60 .
[0030] In spite of the tendency of the plates 43 , 44 to move away from each other, the substrate 2 consequently continues to be retained through levers 53 to 56 .
[0031] In the above described embodiment examples the materials titanium and aluminum were discussed. However, other materials can also be utilized. Aluminum is employed since it is relatively cost-effective. Titanium, which is significantly more expensive than aluminum, is employed since it has a lower coefficient of thermal expansion than aluminum.
[0032] It is understood that the terms “vertical’ and “horizontal” can also be interchanged. | The invention relates to a substrate carrier comprising two vertical plates and two horizontal plates. In order for the substrate during its transport through a sputter unit to be coated uniformly in its margin regions, a lever arrangement is provided between the two vertical plates. The lever arrangement comprises at least one horizontal web which under the effect of heat expands to a lesser degree than the horizontal plates. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to fishing lures formed with a body and a substantially rigidly connected bill as distinguished from lures wherein the body and bill are hinged or otherwise movably connected. Heretofore the bill has afforded limited control of the lure through the water imparting agitation to the body to simulate movement of live bait; it has not been possible to vary running depth of the lure since depth is primarily a function of the angular displacement of the body and bill, and they are fixedly connected or positioned.
OBJECTS OF THE INVENTION
A principal object of the invention is to provide a fishing lure with means for selectively determining running depth.
Another object resides in the provision of a means to control forces or moments on the bill effecting frequency of agitation of the lure. In this connection weight can be selectively added and positioned to further vary these forces and consequent range of agitation.
Another object and feature resides in a skid member arcuately disposed from the leading edge of the lure to reduce or obviate entanglement with objects in the path of the lure.
Still another object is the audible noise, enhancing the invention as a lure, resulting from impact of forces on the diaphragm defined by the thin sheet metal composition of the bill. Attachment of the skid to the leading edge of the bill amplifies this audible vibration when the skid strikes an object.
These and other objects and advantages of the invention will be appreciated upon reading the following description in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 - 5 illustrate, with various attachments, a first embodiment of the invention shown respectively in perspective, side, plan, front and partial side views.
FIGS. 6 and 7 are side and plan views of a second embodiment.
FIGS. 8 and 9 are plan and side views of a third embodiment.
FIG. 10 is a view taken substantially on line 10 -- 10 of FIG. 8.
FIG. 11 is a view similar to FIG. 10 but showing a fourth embodiment wherein the side tabs are upwardly disposed.
FIG. 12 is a partial side view of a fifth embodiment wherein the skid is centrally looped to receive an optional attachment.
FIGS. 13 - 15, with optionally positioned attachments, illustrate side and partial perspective views of a sixth embodiment.
FIG. 16 is a perspective view of a seventh embodiment; and FIGS. 17 and 18 are views taken substantially on corresponding lines 17 -- 17 and 18 -- 18 of FIG. 16.
FIG. 19 is a perspective view of an eighth embodiment; and FIGS. 20 and 21 are views taken substantially on corresponding lines 20 -- 20 and 21 -- 21 of FIG. 19.
FIG. 22 diagramatically analyzes the forces about the pivotal point of attachment to the leader (P) where buoyancy (B) of the lure exceeds and is located rearwardly of its weight (W), and also shows the lure at rest.
FIG. 23 diagrams the forces upon a lure in motion where the bill depends acutely from the longitudinal axis of the body.
FIG. 24 diagrams the forces on a lure having a compound bill with a downwardly bent leading edge.
FIG. 25 graphically illustrates the correlation of bill and body moments at various angular displacements of the bill to the water; it shows the effect on a lure with a bill parallel to the axis of the body (e=0°) and also on a bill depending acutely from the body (e=20°).
FIG. 26 graphically illustrates the effect of straight bill angles from 0° to 40° and also of a compound bill operating at angular displacement to the surface through 90°.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Throughout the drawings the body of the lure is referred to generally as X and the bill as Z.
In the embodiment of FIGS. 1 through 5 body X is shown as a streamlined member flattened on the undersurface 30. Bill Z comprises a major portion 32 inclined downwardly in relation to the longitudinal axis of body X and terminates forwardly in a minor portion or leading edge 34 depending obliquely from major portion 32. The bill and body are joined by a third portion or upper tab 35 defining lateral flanges from the body and increasing projected bill area. Holes 36 in the major portion or diaphragm 32 of bill Z are provided for selective attachment of a leader 38 (FIG. 2), and holes 40 in minor portion 34 may receive optional attachments. In FIG. 2 a weight 41 is carried by an eye 45.
A rail 42 arcuately suspended under body X carries a fixed weight 43 and is formed with central and rearward loops or eyes 44 and 46 to optionally receive hooks 48 (FIG. 1), a flasher 50 (FIG. 2) or a weight 52 (FIG. 5). A skid 53 extending arcuately from leading edge 34 to rail 42 assists the lure over obstacles.
The embodiment of FIGS. 6 and 7 widens edges 54 forwardly of bill Z to define substantially a truncated triangle in plan (FIG. 7). Rail 56 has been raised to juxtapose weight 58 against undersurface 30 of body X, and a single eye 60 is located on rail 56 to receive an optional attachment centrally of the body. A second eye 62 is located to the rear. A metallic member 64 is freely carried by the leader 66 and positioned to knock or beat against skid 53 or bill Z to produce audible vibration. Member 64 should be steel, brass or other conductive metal; a lead weight deadens the audible effect. The audible impulse of the beat against skid 53 is transmitted through skid 53 and leading edge 67 to major portion 68 of bill Z which, being of thin metallic construction, responds like a diaphragm to the impulse.
In the embodiment of FIGS. 8 - 10 major portion 68 of bill Z is bent laterally along bend lines 70 to form downwardly disposed tabs 72. Tabs 72 serve as ribs to stiffen major portion 68 and enhance the diaphragm sensitivity to audible impulse; by decreasing bill area opposed to forward movement in the water the tabs also modify bill eccentricity and consequent agitation of the lure.
In FIG. 11 side tabs 74 are disposed upwardly; this increases agitation of the moving lure.
Skid 53 of FIG. 12 is formed with an eye 76 to receive an optional attachment, shown as a flasher 78.
In FIGS. 13 - 15 major portion 68 of bill Z is symmetrically or longitudinally bisected by an upstanding or L-shaped member 80 perforated with holes 82 for selective attachment of of line 84. Holes 40 in leading edge 34 may optionally receive a weight 86 (FIG. 14) or flasher 88 (FIG. 15). Since holes 40 are spaced laterally, the attachment, in addition to its usual function, affects eccentricity of the bill and agitation of the lure.
In FIGS. 16 - 18 bill Z is bent along a longitudinal line of symmetry 90 to define downwardly disposed sides 92. Similar to downwardly disposed tabs 72 of FIGS. 8 - 10, sides 92 decrease agitation of the moving lure.
In FIGS. 19 - 21, sides 100 are upwardly disposed along symmetrical line 90, increasing agitation.
FIG. 22 diagrammatically sets forth the lure at rest and in motion. In the preferred embodiment buoyancy (B) of the lure exceeds weight (W) and these forces are located to position the center of gravity of the lure proximate the joinder of the body and bill such that at rest the lure normally floats with the bill submerged. As illustrated, these forces of buoyancy and weight are vertically aligned with the lure at rest; as shown to the right, in motion the lower and upper bill forces (D 1 and D 2 ) resulting from pull (P) at point of attachment to the leader displace vertical alignment of forces B and W to effect the agitated, simulated live bait action of the lure.
FIG. 23 diagrams the forces upon a lure in motion where the bill depends acutely from the longitudinal axis of the body at angle e. FIG. 24 diagrams the forces on a lure with a straight bill having the leading edge bent downwardly at angle g. The forces represented by the symbols are as follows:
F 1 = body drag
F 2 = buoyant force
F 3 = weight
F 5 = pull
F 6 = bill force at bill centroid
F 8 = force at centroid of downwardly bent leading edge
T and T 1 = bill or bill section centroid
T 2 = downwardly bent leading edge centroid
r = F 5 position or pull
U = f 2 location or buoyancy
U/2 = location of buoyancy and weight
α, (alpha), = angle displacement from horizonal (water line)
FIGS. 23 and 24 omit the vertical components of F 1 (body drag), F 5 (pull) and F 6 (force at bill centroid).
In the following analysis of forces at work on the lure, body drag (F 1 ) is broken into components of body projected area (A 1 ), body drag coefficient (C 1 ) and dynamic pressure (Q). Different subaltern numbers indicate modifications in projected body area and consequent drag coefficient. Thus, F 1 =A 1 C 1 Q and F 6= A 6 C 6 Q.
In FIG. 23, if A 2= body projected area when f=O, then A 1 =A 2 + A 2 sin f, and F 1= A 2 (1 + sin f)C 1 Q
If A 7 =bill projected area when α=90, then A 6 =A 7 sin α, and F 6 =A 7 sin αC 6 Q
At a given instant, ΣM=O, where M is moment
Assume forces horizontal and vertical as shown
F 1 (u sin f + r sin α) + F 3 (U/2 cos f + r cos α)
= F 2 (U cos f + r cos α) + F 6 (T-r) sin α
Let F 2 = F 3 and let F 2 = nF 1 then
F 1 (u sin f + r sin α) + nF 1 (U/2cos f + r cos α)
= nF 1 (U cos f + r cos α) + F 6 (T - r) sin α, or
F 1 (u sin f + r sin α) + nF 1 (U/2 cos f + r cos α)
- nF 1 (U cos f + r cos α) = F 6 (T-r) sin α
Let U = mT and r = kT
then, F 1 (U sin f + r sin α) - nF 1 U/2 cos f = F 6 (T-r) sin α or,
F 1 (mT sin f + kT sin α) - nF 1 mT/2 cos f = F 6 (T-kT) sin α or,
F 1 [(m sin f + k sin α) - nm/2 cos f] = F 6 (1-k) sin α or, ##EQU1## or, ##EQU2##
then, rearranging and factoring, this becomes what I designate as First Equation: ##EQU3##
If e=O, bill angle = O, and f=α, then First Equation becomes what I designate as Second Equation:
F.sub.1 [k + m(1-n/2 cotα)] = F.sub.6 (1-k)
Assume C 1 = C 6 , then, as stated above, F 1 = A 2 (1 + sin f)C 1 Q and F 6 = A 7 sinαC 6 Q and by substituting, we have
A.sub.2 (1 + sin f)C.sub.1 Q[k + m(1-n/2 cotα)] = A.sub.7 sinαC.sub.6 Q or
A.sub.2 (1 + sin f)[k + m(1-n/2 cotα)] = A.sub.7 sinα(1-k)
Let A R = area ratio A 2 /A 7 , then we have what I designate as Third Equation: ##EQU4##
and from Second Equation, we have what I designate as Fourth Equation:
A.sub.R (1 + sinα)[k + m(1 - n/2 cotα)] = sinα(1 - k)
In FIG. 24,
F 1 (U + r)sinα + F 3 (U/2 + r)cosα = F 2 (U + r)cosα + F 6 (T 1 -r)sinα + F 8 [(T 1 -r + T 1 )sinα + T 2 cos h], or
F 1 (U + r)sinα - F 2 (U/2)cosα - F 8 [(2T 1 - r)sinα + T 2 cos h] = F 6 (T 1 - r)sinα
Let T 2 = pT 1 , then
F 1 (m + k))sin α - F 2 m/2 cosα - F 8 [(2 - k)sinα + p cos h] = F 6 (1 - k)sinα, or
F 1 (m + k) - nF 1 m/2 cotα - F 8 /sinα[(2 - k)sinα + p cos h] = F 6 (1 - k), or
F 1 (k + m(1-n/2 cotα)) - F 8 /sinα [(2 - k)sinα + p cos h] = F 6 (1 - k)
Let A 8 = wA 2 , and substituting for F 1 and F 8 and F 6 ##EQU5## or substituting for A 2 and A 7 ##EQU6## then, this becomes what I designate as: Fifth Equation: ##EQU7## for compound bill, e = O
Summary of bill equations where bill is straight, i.e., e = 0°:
Sixth equation:
A.sub.R (1 + sinα)[k + m(1 - n/2 cotα )] = sinα(1 - k)
where: O<e<90
Seventh Equation: ##EQU8##
For a compound bill where e = O, we have
Eighth equation: ##EQU9##
where, O<2<90, Ninth equation: ##EQU10##
For practical dimensions:
m≈2
n≈1/6
p≈1/3
w≈1/4
The largest error is the expression of F 2 and F 3 as a ratio (n) of F 1 since F 1 varies with velocity. However, this appears acceptable at a given Q for such low velocities.
FIG. 25 graphically diagrams bill moment (solid lines) and body moment (dotted line) of a lure having a straight bill (e = 0°) and a bill depending 20° from the body. It demonstrates the effect of angular displacement of the bill through 90°. With a straight bill it will be observed that body and bill moments are equal at a single angular displacement of the bill from horizontal. With the bill bent downwardly at 20°, bill and body moments match over a substantial range of bill displacements.
FIG. 26 graphically demonstrates the effect of bill angle (e) to the body ranging from 0° to 40° with the bill angularly displaced (α) to the surface of the water through 90°. Based on the assumptions of the above equations, the optimum angle for a straight bill is about 10°. A better correlation is achieved by a compound bill (the curve in dotted line) with a bill angle (e) of 20° terminating in a minor portion downwardly disposed at 20° (g).
Since many different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the specific embodiments described in detail herein are not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims. | A fishing lure is formed of a body and a bill attached at the forward end of the body. The bill includes a major portion adjacent the body and inclined downwardly in relation to the longitudinal axis of the body. The major portion terminates forwardly in a minor portion further inclined downwardly in relation to the major portion. Hook means are carried by the body, and a skid arcuately connects a lower portion of the body and the minor portion or leading edge of the bill to facilitate movement of the lure over obstacles. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to the vulcanization of elastomeric hose utilizing microwave energy in a continuous process.
There are various method and techniques employed in the manufacture of elastomeric hose which includes forming an unvulcanized elastomeric hose structure around a flexible or rigid mandrel, encasing the hose and mandrel and thence vulcanizing the hose by molding a sheath such as a lead sheath around the hose and thence vulcanizing the hose. In this instance the lead must be removed by stripping the outer lead sheath and thence removing the internal mandrel from the vulcanized hose. This method maintains a pressure on the hose while being vulcanized. Modifications on this technique which eliminates the lead sheath is a continuous type process wherein the uncured hose is passed into a vulcanizing fluid chamber (heated fluids) where the hose is wrapped around a moving spool and slowly withdrawn from the chamber. Another method passes the hose through a tubular chamber by means of hot vulcanizing fluid. In the latter case, higher pressures are required on the curing fluids as well as the transporting fluids. Additional safety problems are encountered when using hot vulcanizing pressurized fluids. The use of the lead sheaths is cumbersome, requiring expensive equipment for handling and impedes rapid production. Considerable quantities of lead is required for this process with an ever present waste problem whereat in such a process. The present invention utilizes a microwave curing tunnel mold that maintains pressure on the hose or curing product which tunnel moved is transparent to the microwave energy thereby increasing the efficiency of the curing unit while enhancing the consistency of the finished product. Such method and apparatus eliminates the need for high temperature pressurized fluids and the costly use of the equipment and materials for the lead sheath process.
SUMMARY OF THE INVENTION
The present invention contemplates an apparatus and process for curing an elastomeric article in a mold that is transparent to the microwave energy that effects the cure thereof as the article is conveyed through a tunnel on an endless conveyor that is also transparent to the microwave energy. The devices for transmitting the microwave energy are located in the tunnel on either side of the path of movement of the article and mold in the conveying run of the conveyor belt.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammic side elevational view of an apparatus showing a production line for manufacturing a reinforced hose in accordance with the present invention.
FIG. 2 is a cross-sectional view taken along line 2--2 of FIG. 1 of the conveyor belt mold and guides showing the microwave transmitters relative thereto.
FIG. 3 is a cross-sectional view of a modified form of conveyor belt mold showing a belt being captively secured thereby as the belt is being subjected to microwave energy for curing.
FIG. 4 is a further modification of the invention showing a side elevational view of the conveying run transporting a mold which is subjected to opposing microwave transmitting device.
FIG. 5 is an enlarged view partly in section of a mold taken along line 5--5 of FIG. 4.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring to the drawings, wherein like reference numerals designate like or corresponding parts throughout the several views, there is shown in FIG. 1 a continuous screw type extruder 11 having a hopper 12 which provides the means for introducing a suitable mixed blend into the extruder 11 for extrusion through a die 13 a tubular hose 14. Although not shown the hose may be cooled by passing such hose 14 through a cooling apparatus and thence such hose is drawn forwardly by a caterpillar type pulling apparatus 15 having a pair of upper roller 16 along with an endless belt 17 cooperative with a pair of rollers 18 along with an endless belt 19. The tubular hose 14 then passes to a cord winding machine 20 which winds a layer of textile thread onto the hose. Although only one winding machine 20 is shown, it is contemplated to have at least two winding machines which wind two layers of textile thread in opposite directions onto the tubular hose 14. The covered hose is then drawn into the vulcanizing unit 25 by a pair of endless belt molds 26 and 27. The unit 25 includes a housing 28 suitably supported and mounted in line with the cord winding machine 20. The respective ends of such housing 28 has openings to permit the movement of the endless belt therethrough along a pass line that is in alignment with the axial centerline of winding machine 20. Endless belt mold 27 extends along the upper portion of housing 28 between rollers 30 and 31 and on leaving such housing is directed downwardly and around idler roller 32 and thence directed horizontally along the pass line to a roller 33. The conveyor belt mold 27 is trained about roller 33 and then upwardly around roller 31. Endless belt mold 26 extends along the lower portion of housing 28 between rollers 35 and 36 and is thence directed upwardly and rearwardly over roller 37, and thence horizontally along the pass line and in contact with belt 27 to roller 38 at the forward portion of the housing. Belt 26 is trained over rollers 38 and thence downwardly under roller 35. Although only four rollers are shown for the respective belt molds 26 and 27, sufficient rollers are provided to maintain the endless belts in their path of movement. The respective belts 26 and 27 as seen in FIG. 2 are grooved at 50 and 51 respectively along their outer central periphery such that on coming together such grooves define a cylindrical bore for the full length of the pass line. As the endless belt molds 26 and 27 come together at the forward portion of housing 25, such belts captively engage the linearly moving hose 14 and move together at the same horizontal speed. As the belts 26 and 27 move through housing 25, they are guided by four spaced guide plates 40-41-42 and 43 suitably supported withing housing 25. Plates 40 and 41 are disposed opposite each other in vertical alignment while plates 42 and 43 are disposed opposite each other and are cooperative with plates 40 and 41 ato define a rectangular passageway therebetween which functions as a guide means to apply pressure onto the belt molds 26 and 27 which in turn transfer the pressure to the hose 14 located within grooves 40 and 41. The guide plates 40 through 43 are constructed from a material such as Teflon which is transparent to microwave energy for a purpose to be described. Such guide plates extend through the entire length of the housing 25. A plurality of vertically spaced pairs of UHF apparatus 45 are mounted within housing 25 in longitudinally spaced relationship along the pass line of grooves 50 and 51. The UHF apparatus are devices which provide electromagnetic waves to effect vulcanization of the hose 14 within grooves 50 and 51 of belts 26 and 27. The microwave energy and power is generated by means old and well known in the art. Such UHF apparatus include an emitter to facilitate the directing of the microwave energy. Such microwave energy devices or generators are available from Cober Electronics, Inc. Stamford, Conn. Microwave is defined as very short electromagnetic wavelengths in the order of 60 centimeters or less and frequencies in excess of 300 MHZ. 2450 MHZ and 915 MHZ are the frequency bands used in industrial applications. As seen in FIGS. 1 and 2 the electromagnetic waves are directed from the upper units 45 and the lower unit 45 directly towards the center line of hose 14. Since the guide plates 40-41-42 and 43 are constructed of Teflon which are transparent to microwave energy and the belts 26 and 27 are constructed of flexible silicone, which is also transparent to the microwave energy, the microwave energy passes directly to the heating and vulcanizing the hose 14, which hose is captively retained in the silicone mold of grooves 50 and 51 in belts 26 and 27 which applies the pressure during this curing process. The number of UHF apparatus 45 located within the tunnel of housing 25 is dependent on size of the product to be cured and the length of the tunnel. The curing can be controlled by utilizing only a given number of such UHF apparatus 45 within the tunnel of housing 25. In addition, the speed of the movement of the belts 26 and 27 can be electronically controlled for a preselected speed.
In the operation of the described apparatus, suitable raw material such as elastomeric material of suitable receptivity and physical properties is fed into the hopper 12 wherein such preblended mix is extruded from the die 13 of the extruder 11 as a hose which may be cooled by suitable means old and well known in the art. The hose 14 is then fed via the caterpillar type conveying apparatus 15 to a braiding machine 20 wherein suitable yarn is applied or wound onto the hose 14. Although a single braider unit is shown, additional units may be located in line with the braider unit 20 to provide the necessary reinforcement of yarn onto such hose 14. The reinforced hose is then fed into the nip of converging conveyor belt molds 26 and 27 such as to position the unvulcanized hose 14 within the grooves 50 and 51 of such belts. As the conveyor belt molds 26 and 27 enters the housing 25, the guide plates 40-41-42 and 43 exert a pressure onto the belt molds while the microwave emitters of UHF apparatus 45 heat the hose 14 to effect vulcanization. Since the belt guide plates and the conveyor belt molds 26 and 27 are transparent to the microwave energy the vulcanization process is highly efficient. The energy requirement to effect vulcanization is low since the energy is directed to the hose 14, which on heating up retains its level of energy within the belt mold due to the insulating properties of the silicone mold. The microwave energy penetrates the silicone belt molds with ease and an insignificant amount of energy is lost to the mold as the major portion of the microwave energy is used in heating up the hose within the mold.
As the belt molds 26 and 27 exit from the housing 25, belts 26 and 27 separate, allowing the hose 14 to move rectilinearly onto conveyor 53 where such hose 14 is cooled by a plurality of air jets 54. The hose is then wound up onto a spool 55 as the endless belt molds 26 and 27 continue in their endless path.
A modification of the described embodiment is shown in FIG. 3 wherein such endless conveyor belt mold 26' and 27' has a rectangular groove 60 and 61 to receive an unvulcanized conveyor belt 62, which in turn is vulcanized in the same manner as the previously described embodiment within the tunnel of housing 25.
A further modification is shown in FIGS. 4 and 5 wherein the previously described housing 28 is replaced by a similar elongated housing 28' that has a central opening 65 in line with a platform 66 shown schematically in FIG. 4. Since platform 66 facilitates the loading of individual mold into the housing 28' which has a plurality of horizontally spaced UHF apparatus 67 located therein in the same manner as UHF apparatus 45 described above. An endless conveyor 70 is suitably trained within such housing 28 such that its return run is along the bottom of such housing while its conveying run is in line with the platform 66 and roller 71. As described above, endless conveyor 70 is made of silicone or nylon to assure the passage of the microwave energy through it without absorbing energy therefrom. A suitable horizontally disposed guide plate 72, made of ceramic, supports the conveying sum of endless conveyor 70 while also being transparent to microwave energy. A mold 75 that is fed to the conveyor 70 is a generally cylindrically shaped container with a lid 76 (also ceramic) suitably locked thereon. The mold 75 has a cylindrical inner liner 78 that is cup shaped such that a product to be cured, such as a rubber cylinder 80 is securely held by such inner liner 78 to apply and maintain a pressure thereon. A cap or disc 81 is placed onto the cylinder 80 prior to the placement of lid 76. The liner and cap 81 is placed onto the cylinder 80 prior to the placement of lid 76. The liner and cap 81 is also made from a material such as ceramic, nylon, fused quartz or silicone such as to be transparent to the microwave energy. As in the first described embodiment, the linear movement of the conveyor, conveys the rubber product 80 to be vulcanized past the microwave heaters 67 as the product is maintained under pressure to effect vulcanization thereof.
It will be apparent that, although a specific embodiment and certain modifications of the inventions have been described in detail, the invention is not limited to the specifically illustrated and described constructions since inventions may be made without departing from the principles of the invention. | The vulcanizing of elastomeric articles by captively securing the article to be cured under pressure by a mold that is transparent to microwave energy. The mold in the preferred embodiment is a pair of conveying runs which define cooperatively a mold cavity therebetween. The microwave transmitting devices are located along the path of movement of such conveying runs. | 8 |
This is a divisional application based on application Ser. No. 08/871,596, filed Jun. 6, 1997, now U.S. Pat. No. 5,972,264.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to centrifuge rotors made from composite materials, and relates more particularly to a process of fabricating structures, including centrifuge rotors, by resin transfer molding, and the resulting structures or rotors.
2. Description of the Relevant Art
Centrifuges are commonly used in medical and biological research for separating and purifying materials of differing densities. A centrifuge includes a rotor typically capable of spinning at tens of thousands of revolutions per minute.
A preparative centrifuge rotor has some means for accepting tubes or bottles containing the samples to be centrifuged. Preparative rotors are commonly classified according to the orientation of the sample tubes or bottles. Vertical tube rotors carry the sample tubes or bottles in a vertical orientation, parallel to the vertical rotor axis. Fixed-angle rotors carry the sample tubes or bottles at an angle inclined with respect to the rotor axis, with the bottoms of the sample tubes being inclined away from the rotor axis so that centrifugal force during centrifugation forces the sample toward the bottom of the sample tube or bottle. Swinging bucket rotors have pivoting tube carriers that are upright when the rotor is stopped and that pivot the bottoms of the tubes outward under centrifugal force.
Many centrifuge rotors are fabricated from metal. Since weight is a concern, titanium and aluminum are commonly used materials for metal centrifuge rotors.
Fiber-reinforced, composite structures have also been used for centrifuge rotors. Composite centrifuge rotors are typically made from laminated layers of carbon fibers embedded in an epoxy resin matrix. The fibers are arranged in multiple layers extending in varying directions at right angles to the rotor axis. During fabrication of such a rotor, the carbon fibers and resin matrix are cured under high pressure and temperature to produce a very strong but lightweight rotor. U.S. Pat. Nos. 4,781,669 and 4,790,808 are examples of this type of construction.
Composite centrifuge rotors are stronger and lighter than equivalent metal rotors, being perhaps 60% lighter than titanium and 40% lighter than aluminum rotors of equivalent size. The lighter weight of a composite rotor translates into a much smaller mass moment of inertia than that of a comparable metal rotor. The smaller moment of inertia of a composite rotor reduces acceleration and deceleration times of a centrifugation process, thereby resulting in quicker centrifugation runs. In addition, a composite rotor reduces the loads on the centrifugal drive unit as compared to an equivalent metal rotor, so that the motor driving the centrifuge will last longer. Composite rotors also have the advantage of lower kinetic energy than metal rotors due to the smaller mass moment of inertia for the same rotational speed, which reduces centrifuge damage in case of rotor failure. The materials used in composite rotors are resistant to corrosion against many solvents used in centrifugation.
A disadvantage of composite centrifuge rotors is that the loading of the rotor due to centrifugal forces can cause delaminations and failure of the structure. Reinforcing structures such as outer shells may be necessary to provide adequate structural strength, such as disclosed in U.S. Pat. Nos. 5,362,301 and 4,790,808. Another disadvantage is that extensive and costly machining of the laminated core is required in order to form the outer shape of the rotor and to form the cell holes that receive the sample tubes or bottles containing the samples to be centrifuged.
SUMMARY OF THE INVENTION
In accordance with the illustrated preferred embodiment, the present invention is a method for fabricating fiber-reinforced composite structures, including centrifuge rotors, by resin transfer molding (RTM), and the resulting composite structures. The method basically involves loading reinforcing fibers into a mold and then injecting resin into the mold to coat the fibers to form the composite structure. Either one or two molds can be used for the process. If two molds are used, most or all the reinforcing fibers are loaded into a first mold and then cured into a porous fiber structure and then the porous fiber structure is transferred to a second mold for resin injection and curing.
One aspect of the present invention is a method for fabricating a fiber-reinforced composite structure in a single mold, including the steps of: (a) forming fabric preforms corresponding to the surface of the structure; (b) placing some of the fabric preforms into a mold; (c) placing chopped fibers in the mold; (d) placing the remainder of the fabric preforms into the mold so that the fabric preforms are adjacent to the interior surfaces of the mold and the chopped fibers are inside the fabric preforms; (e) injecting resin into the mold to coat all the fabric preforms and chopped fibers; (f) curing the resin in the mold; and (g) then removing the completed structure from the mold.
Another aspect of the method is to use two molds, a first mold to form the preforms and chopped fibers into a porous fiber structure called a “birds nest,” and a second mold for the resin injection. The molds may incorporate a mold insert or mandrel that is moved from the birds nest mold to the injection mold with the birds nest structure.
Another aspect of the method is the forming of the fabric preforms, which is done by applying resin in the form of a solid powder or other forms to a piece of fabric, heating the fabric and then inserting it into a forming tool, which forms the fabric into the desired shape. The resin adds stiffness so that the fabric preform can retain its shape until it is placed into the mold for forming the birds nest and/or resin injection.
Yet another aspect of the present invention is a fiber-reinforced composite structure comprising a skin layer of reinforcing fabric adjacent the surfaces of the structure, chopped fibers distributed throughout the interior of the structure and under the skin layer, and epoxy resin throughout the structure, which binds the fabric and chopped fibers together into a fiber-reinforced composite structure. Fabric preforms are positioned adjacent to the surfaces of the structure, and provide fiber reinforcement for the entire surface. The chopped fibers are located randomly within the interior of the structure, and provide fiber reinforcement throughout the structure.
A preferred structure resulting from the resin transfer molding method is a centrifuge rotor, and so the invention encompasses both the centrifuge rotor itself and the method of making it.
The present invention provides a simple and cost-effective method of fabricating fiber-reinforced composite centrifuge rotors. The present invention uses composite materials and thus retains the advantages of all-composite construction in terms of light weight, low energy, and corrosion resistance, while reducing weight and eliminating material waste, costly machining, and add-on reinforcing shells.
The features and advantages described in the specification are not all inclusive, and particularly, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification and claims hereof. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of several fabric preforms used in the resin transfer molding (RTM) of a centrifuge rotor according to the present invention.
FIG. 2 is a perspective view of an assembly of the fabric preforms of FIG. 1 .
FIG. 3 is a sectional view of the assembly of fabric preforms of FIG. 2, taken along section line 3 - 3 .
FIG. 4 is a perspective view of a bottom fabric preform according to the present invention.
FIG. 5 is a sectional view of a die set used to form the bottom fabric preform of FIG. 4 .
FIG. 6 is a perspective view of a side fabric preform according to the present invention.
FIG. 7 is a sectional view of a die set used to form the side fabric preform of FIG. 6 .
FIG. 8 is a perspective view of a top fabric preform according to the present invention.
FIG. 9 is a sectional view of a die set used to form the top fabric preform of FIG. 8 .
FIG. 10 is a perspective view of a cell-hole fabric preform according to the present invention.
FIG. 11 is a perspective view of an alternative cell-hole fabric preform according to the present invention.
FIG. 12 is a sectional view of a die set used to form the cell-hole fabric preform of FIG. 10 .
FIG. 13 is a sectional view of a birds nest mold used in fabricating the centrifuge rotor of the present invention.
FIG. 14 is a side view, partially in section, of a molding machine utilizing the birds nest mold of FIG. 13 and the injection mold of FIG. 15 .
FIG. 15 is a sectional view of an injection mold used in fabricating the centrifuge rotor of the present invention.
FIG. 16 is a sectional view of the centrifuge rotor of the present invention after completion of the molding process.
FIG. 17 is a perspective view of the centrifuge rotor of the present invention with sample holders and a hub installed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 through 17 of the drawings depict various preferred embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.
A preferred embodiment of the present invention is a method of fabricating a composite material centrifuge rotor by resin transfer molding (RTM), and the resulting composite rotor. This method of fabricating composite structures, however, is not restricted to fabricating only centrifuge rotors, because it is useful for fabricating advanced composite structures other than centrifuge rotors.
The composite structures made according to the present invention have reinforcing fibers in two forms—continuous fiber in the form of fabric preforms of woven cloth or braided tubing located throughout all surfaces of the structure, and chopped fibers located throughout the interior of the structure. The reinforcing fibers are encapsulated in an epoxy resin to form the composite structure. The fabric preforms are positioned adjacent to the surfaces of the structure, and provide fiber reinforcement of the entire surface. The chopped fibers are located randomly within the interior of the structure, and provide fiber reinforcement below the surface of the structure.
The method of fabricating composite structures by resin transfer molding according to the present invention includes several basic steps. First, several fabric preforms are made by pressing woven cloth or braided tubing into desired shapes that when assembled generally conform to the surfaces of the finished structure. Then, the fabric preforms are assembled in a mold and chopped fibers are added to the interior of the space defined by the fabric preforms and mold. The mold has an interior cavity with walls that correspond to the shape of the composite structure. After all the reinforcing fibers, both chopped fibers and continuous fibers in the form of fabric preforms, are in the mold, the mold is evacuated and epoxy resin is injected to encapsulate the fibers. The mold is then heated to cure the epoxy resin. After the structure cures in the mold, the mold is opened and the finished structure is removed.
FIGS. 1-3 illustrate a fabric preform assembly 10 and the individual fabric preforms used in fabricating a six cell-hole fixed-angle centrifuge rotor according to the present invention. The fabric preform assembly 10 includes a bottom fabric preform 12 , a side fabric preform 14 , a top fabric preform 16 , a hub fabric preform 18 , and six cell-hole fabric preforms 20 . FIG. 1 also shows a metal hub ring 22 . FIG. 1 shows both the individual fabric preforms 12 , 14 , 16 , 18 , and 20 , and the assembly 10 resulting from combining all the fabric preforms. Note that the lines on the surfaces of the fabric preforms are intended to denote the surface contours, not structural features.
Each fabric preform is made from a woven cloth or braided tube and is shaped to approximate the surface contours of the finished rotor structure. As shown in FIG. 3, the bottom fabric preform 12 defines a lower surface of the fabric preform assembly 10 , and overlaps an outer edge of the side fabric preform 14 at a circumferential band 22 . An upper edge of the side fabric preform 14 overlaps an outer edge of the top fabric preform 16 at a circumferential band 24 . The top fabric preform 16 overlaps the cell-hole fabric preforms 20 at the periphery 26 of the cell holes, and overlaps the hub fabric preform 18 at 28 . The hub fabric preform 18 also overlaps the bottom fabric preform 12 at 30 . As used herein, the term overlap refers to the edges or borders of two fabric preforms overlying each other, regardless of which preform is innermost or outermost. Preferably, the amount of overlap is about one-half inches. The metal hub ring 22 , not shown in FIG. 3, is sized to fit just inside of the hub fabric preform 18 so as to provide an adapter to a hub assembly for the finished centrifuge rotor.
The fabric preform assembly 10 defines an interior void space 32 which, as described further below, is filled with chopped fibers before resin is added. In the process of fabricating a centrifuge rotor, described herein, the fabric preform assembly 10 is a conceptual structure rather than an actual, stand-alone structure. As described below, portions of the fabric preform assembly are assembled in a mold, the interior void space 32 is filled with chopped fibers, and then the remainder of the fabric preforms are put into place, all prior to the step of resin injection.
FIGS. 4-12 illustrate the fabric preforms and the tools used to form them. Specifically, the bottom fabric preform 12 is shown in FIG. 4 and its forming tool 40 is shown in FIG. 5 . The bottom fabric preform 12 is axi-symmetric about axis 42 , and includes a hole 43 at the axis to accommodate the hub. The tool 40 includes a lower mold 44 and an upper mold 46 that are shaped to the desired contour of the bottom fabric preform 12 .
The bottom fabric preform 12 is formed as follows. First, a piece of woven cloth, composed of carbon fibers, is cut roughly to the size of the tool. Then a small amount (preferably about 4% of the weight of the cloth, and preferably less than about 6% of the weight of the cloth) of powered solid epoxy resin is applied evenly to the top surface of the cloth and the cloth and applied resin is radiantly heated for about forty seconds, sufficient for the resin to melt and to be absorbed by the cloth. Then the heated cloth is placed between the lower and upper molds 44 and 46 and the tool 40 is closed, thereby stretching the cloth to conform to the contours of the mating surfaces of the mold. After about one minute, the mold is opened and the formed cloth 48 is removed. A sheet of PTFE or other non-stick material may be used between the cloth and the mold to prevent sticking to the mold. After the formed cloth 48 is removed from the mold, the excess portions of the cloth at the outer edge 49 and at the center are trimmed away, leaving the bottom fabric preform 12 . A template may be used to guide the trimming of excess fabric. The fabric preform is stiff but bendable, much like a formed felt hat.
The side fabric preform 14 and its forming tool 50 are illustrated in FIGS. 6 and 7. The side fabric preform 14 is axi-symmetric about axis 52 , and includes a central hole 53 to accommodate the top fabric preform 16 . The tool 50 includes a lower mold 54 and an upper mold 56 that are shaped to the desired contour of the side fabric preform 14 . The side fabric preform 14 is formed by the same process as described above for forming the bottom fabric preform, the only significant difference being the shape of the molds 54 and 56 . The formed cloth 58 is trimmed at the outer edge 60 and inner edge 62 , resulting in the side fabric preform 14 . As an alternative to woven cloth of carbon fibers, a braided tube of carbon fibers could be used for the fabric in the side fabric preform 14 .
The top fabric preform 16 and its forming tool 64 are illustrated in FIGS. 8 and 9. The top fabric preform 16 is axi-symmetric about axis 66 , and includes a central hole 68 to accommodate the hub fabric preform 18 and six holes 70 to accommodate the cell-hole fabric preform 20 . The tool 64 includes a lower mold 72 and an upper mold 74 that are shaped to the desired contour of the top fabric preform 16 . The top fabric preform 16 is formed by the same process as described above for forming the bottom and side fabric preforms, the only significant difference being the shape of the molds 72 and 74 . The formed cloth 76 is trimmed at the outer edge 78 and at the holes 68 and 70 , resulting in the top fabric preform 16 . Cloth woven of carbon fibers is the preferred material for the top fabric preform 16 .
Two embodiments of the cell-hole fabric preform 20 are shown in FIGS. 10 and 11, and the associated forming tool 80 is shown in FIG. 12 . The cell-hole fabric preform 20 is axi-symmetric about an axis 82 and has an open end with a flange 84 and a closed bottom end 86 . The cell-hole fabric preform 20 A of FIG. 10 is composed of braided tubing of carbon fibers. The cell-hole fabric preform 20 B of FIG. 11 is composed of a sleeve 88 formed from braided tubing and a hemispherical cap 90 formed from woven cloth, then bonded together.
The forming tool 80 shown in FIG. 12 can be used for forming either cell-hole fabric preform. The tool has two parts—a male mold composed of a base 92 and a mandrel 94 , and a female mold composed of a shell 96 and a case 98 . The cell-hole fabric preform 20 A of FIG. 10 is formed by placing a piece of braided tubing on the mandrel 94 and tying off its upper end 100 with a length of yarn 102 . Then about 6% by weight of powdered epoxy resin is applied to the fabric, which is then heated by a heat gun until the resin is melted and absorbed into the fibers, then the shell 96 and case 98 are placed on the mandrel to form the preform. The tied-off end of the braided tubing protrudes through a hole 104 in the top of the shell 96 . The formed cell-hole fabric preform is removed from the tool and the excess material is trimmed away.
The cell-hole fabric preform 20 B of FIG. 11 is formed in multiple steps. First, braided tubing is formed into the sleeve 88 using the steps described above for forming the preform 20 A, except that the tied-off end is trimmed away. The cap 90 is formed on the hemispherical end of the mandrel 96 by placing a piece of woven cloth on the mandrel and a O-ring to hold it in place, then applying about 6% by weight of powdered epoxy resin to the fabric, then heating the resin with a heat gun until it is melted and absorbed by the fabric. The cap is removed from the mandrel and trimmed to size. Then, the sleeve 88 is again placed on the mandrel, powdered epoxy resin is applied to the sleeve and cap where they will overlap, the cap is placed on the mandrel over the sleeve, a PTFE sheet is placed over the mandrel and fabric components and the resin is heated with a heat gun. The melted resin bonds the cap 90 to the sleeve 88 to complete the formation of the cell-hole fabric preform 20 B.
FIG. 13 shows a birds nest mold 110 used to consolidate the fabric preforms and chopped fibers into a “birds nest,” which is a porous structure of fibers bound together with a small amount of resin. The birds nest mold 110 includes a base 112 , midsection 114 , top 116 , hub base plate 118 , hub top plate 120 , six cell-hole mandrels 122 , and a center mandrel 124 assembled as shown in FIG. 13 . Note that the birds nest mold 110 (and the injection mold 140 of FIGS. 14 and 15) are oriented with the rotor upside down. The birds nest mold 110 has a cavity with walls that conform to the desired shape of the finished composite structure.
Assembly of the birds nest mold 110 begins with the hub top plate 120 . The hub fabric preform 18 is inserted into the central hole 68 (FIG. 8) of the top fabric preform 16 and the two preforms are placed on the hub top plate 120 . The six cell-hole mandrels 122 are inserted through the holes 70 in the top fabric preform 16 and through corresponding holes in the hub top plate 120 . This assembly is then placed on the hub base plate 118 and the six cell-hole mandrels 122 and the hub top plate 120 are secured to the base with bolts 126 . The center mandrel 124 is inserted through the hub fabric preform 18 and into the hub base plate 118 . The assembly is then turned over and the side fabric preform 14 is positioned with its outer edge overlapping the top fabric preform 16 . The assembly is turned over again and the cell-hole fabric preforms 20 are placed on the six cell-hole mandrels 122 . Then the assembly is placed into the base 112 of the birds nest mold and secured by a bolt 128 . At this point, the preforms are arranged as shown in FIGS. 2 and 3 with the exception that the bottom fabric preform 12 is not yet in place, which allows access to the void space 32 inside the preforms to add the chopped fibers.
After the hub assembly, as described above, is placed in the mold base 112 , chopped carbon fibers are added. The amount of chopped fibers depends on the desired percentage of fiber to the overall weight of the finished rotor. In the preferred embodiment, fiber (from both the fabric preforms and the chopped fibers) makes up about 60% of the weight of the rotor. The chopped fibers are added to the birds nest mold, taking care to distribute them around and under the cell-hole mandrels 122 . After most of the chopped fibers have been added, the upper half of the mold (midsection 114 and top 116 ) is lowered to the base 112 , thereby compressing the chopped fibers. The midsection 114 is then bolted to the base 112 and the top 116 is raised to provide access to the middle of the mold cavity. The remainder of the chopped fibers are then added and the mold is again closed. The mold is then heated to about 240° F. for about one hour to cure the birds nest assembly. The resin already present in the preforms helps to bind the preforms and chopped fibers together into a porous structure—the birds nest. Optionally, additional powdered epoxy resin may be added along with the chopped fiber to provide more binder material for the birds nest. Preferably, the resin is less than 45% of the weight of the chopped fibers.
The process of making the birds nest, described above, does not include the step of placing the bottom fabric preform 12 in the birds nest mold. One could add the bottom fabric preform 12 to the birds nest prior to heating and curing in the birds nest mold, but it is preferred to add the bottom fabric preform to the birds nest when it is transferred to the injection mold.
The injection mold 140 , shown in FIGS. 14 and 15, is preferably positioned next to the birds nest mold 110 in a molding machine 142 . Each mold has a corresponding hydraulic ram 144 and 146 for opening and closing the mold. The injection mold 140 includes an injection port 148 and vacuum/exit port 150 . The interior walls of the cavity 152 of the injection mold, including the hub assembly of the birds nest mold, defines the final shape of the rotor. The injection mold uses the hub base plate 118 , hub top plate 120 , and cell-hole mandrels 122 to maintain the shape of the birds nest during the molding process.
In use, the birds nest along with the support structure of the hub base plate 118 , hub top plate 120 , and cell-hole mandrels 122 are placed into the injection mold 140 . The bottom fabric preform 12 is placed on top of the birds nest and the hub ring 22 is positioned inside the hub fabric preform 18 . A center hub 154 is installed and the assembly is fastened in the mold by a bolt 156 . The injection mold 140 is then closed and evacuated by applying a vacuum to the vacuum/exit port 150 . The mold is heated to about 120° F. to facilitate the flow of resin. Resin is then injected through the injection port 148 until it fills the mold and comes out of the vacuum/exit port 150 . The pressure of the injected resin and the temperature of the mold are both gradually increased, to about 350 psi and 170° F., respectively, to assure that the resin completely wets the fibers and fills all voids inside the mold. After the resin injection is completed, the injection mold 140 is heated to about 270° F. for about two hours to cure the molded structure. Then, the mold is cooled by water to room temperature and the molded rotor is removed. The hub base plate 118 , hub top plate 120 , and cell-hole mandrels 122 are removed from the molded rotor, and any post-molding clean-up is then performed.
The injection mold 140 may be used in a single mold process, wherein the fabric preforms and chopped fibers are loaded individually into the injection mold, thus eliminating the step of forming the birds nest in the birds nest mold.
The completed rotor 160 is shown in a sectional view in FIG. 16 . Cell holes 162 are present where the cell-hole mandrels 122 were. The entire surface of the rotor 160 is reinforced by the fabric preforms that lie at and just below the surface of the rotor. The interior of the rotor 160 is reinforced by the chopped fibers that are distributed throughout the interior. Resin binds all the fibers, both the fabric preforms and the chopped fibers, together. The hub ring 22 is at the inner diameter of the rotor 160 , and receives a hub assembly 166 that couples the rotor to a centrifuge spindle. The result is a fiber-reinforced composite rotor that needs little if any post-molding finishing.
FIG. 17 shows the rotor 160 with sample holders 164 in the cell holes. The hub 166 is also shown.
From the above description, it will be apparent that the invention disclosed herein provides a novel and advantageous fixed-angle centrifuge rotor fabricated from fiber-reinforced composite material, and an associated method of fabrication. The foregoing discussion discloses and describes merely exemplary methods and embodiments of the present invention. As will be understood by those familiar with the art, the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For example, although a centrifuge rotor with fixed-angle cell holes (inclined toward the axis of rotation) is disclosed, a centrifuge rotor with vertically-oriented cell holes can also be made. As another example, although only one example of incorporating a prefabricated component (metal hub ring) into the molded structure is disclosed, a wide variety of prefabricated components can be so used. Further, the fabric preforms need not conform to the entire surface, but could be used to reinforce only the most heavily loaded regions of the structure. In addition, since the positioning of the fabric preforms need not be limited to the surface of the composite structure, more generally the fabric preforms (and the chopped fibers) may be located anywhere within the composite structure. Moreover, although only one example of a composite structure is disclosed, a wide variety of composite structures can be made according to the present invention. Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims. | A method for fabricating fiber-reinforced composite structures, including centrifuge rotors, by resin transfer molding (RTM) is disclosed. The method involves loading reinforcing fibers into a mold and then injecting resin into the mold to coat the fibers to form the composite structure. Two types of reinforcing fibers are used—fabric preforms at the surfaces of the structure and chopped fibers at the interior of the structure. Also disclosed is a fiber-reinforced composite structure comprising a skin layer of reinforcing fabric, chopped fibers distributed throughout the interior of the structure, and epoxy resin that binds the fabric and chopped fibers together into a fiber-reinforced composite structure. The resin transfer molding method is especially useful for fabricating composite centrifuge rotors. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Stage application of International Application No. PCT/EP2010/005577, filed on Sep. 11, 2010, which claims priority of German patent application number 10 2009 048 641.0, filed on Sep. 30, 2009, both of which are incorporated herein by reference in their entireties.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of assembling window sashes. More specifically, the present invention relates to a method for assembling a window sash having an integrated insulating glass pane.
2. Description of the Prior Art
The invention starts at a method comprising the features specified in the preamble of patent claim 1 , namely, a method for forming a device for assembling window sashes comprising an integrated insulating glass pane, wherein the window sashes comprise a frame formed from plastic hollow profiles comprising an inner face, an outer face facing away from the inner face, and two flanks which connect the inner face and the outer face to each other, wherein the frame, on the inner face of the frame comprises two webs which are parallel to each other, which constitute an all-around delimitation of the window opening of the window sash and which are adhesively secured to two glass plates which are held spaced apart by the two webs. Such a method is known from U.S. Pat. No. 6,286,288 B1 and from U.S. Pat. No. 7,097,724 B2 for producing sliding sashes. These publications disclose window sashes for sliding sashes and methods for the production thereof, which are known under the identification “sashlite”.
In the case of the “sashlite” method, a rectangular or square frame is initially formed from an extruded plastic hollow profile, in that the four legs of the frame are cut from the plastic hollow profile and are welded to each other in pairs at their ends by means of ultrasound for forming the corners of the frame. On its inner face, the frame has two webs, which are parallel to each other. A paste-like adhesive compound, in which a moisture-binding material, in particular molecular sieves in the form of powder, is embedded, is injected into the space between these two webs. A line of a sealing and adhesive compound, by means of which two glass plates are adhesively secured to the two webs, which serve as spacers for the two glass plates, is applied all around, at all four legs of the frame, on the outside of the two webs. Such a sealing and adhesive compound will hereinbelow be referred to as sealing compound. It has the object of establishing a fixed connection between the webs of the frame, which are directed inwardly, and the glass plates, and to seal the gap between the webs and the glass plates against the penetration of moisture and against a loss of a heavy gas, which is possibly filled into the space between the glass plates.
The pre-manufactured frame is placed onto a horizontal conveyor track and is conveyed to a processing station, in which the adhesive compound, which includes the moisture-binding material, is initially injected into the space between the two webs at all four legs of the frame. Said space is open towards the respective opposite leg of the frame. A line of the sealing compound is then applied to the one of the two webs, which is located on the top, and a first glass plate is adhesively secured thereto. The frame is then turned over on the horizontal conveyor track, so that the web having the first glass plate, which adheres thereto, is located on the bottom and the second one of the two parallel webs is located on top. A line of the sealing compound is then applied all around to the web, which is now located on top, and the second glass plate is adhesively secured to this line.
Outside of the area, which is covered by the glass plates, one of the two webs has a bore, which leads into the space between the glass plates. The space between the two glass plates can be vented by means of this bore when the two glass plates are pressed against the webs, whereby the space between the glass plates is decreased. The pressing of the glass plates takes place in that, e.g., rollers act on the glass plates in the area of the two webs and the glass plates are pressed against the webs through this, whereby the sealing compound is flattened and the gap between the two glass plates is sealed. It is known as another possibility for pressing the two glass plates of a sashlite window against the two webs of the window frame, to suck air from the space between the two glass plates through the bore, which is provided in one of the webs, so that a low pressure, which pulls the glass plates against the webs and thus flattens the sealing compound, is created in the space.
In the case of the sashlite method, it is furthermore known to insert two small tubes into the bore in one of the two webs of the window frame. A heavy gas, e.g. argon, is blown through one of the small tubes into the space between the two glass plates. Air or a mixture of air and the heavy gas is extracted from the space between the two glass plates by suction through the other small tube. Through this, the air in the space between the glass plates is partially replaced with the heavy gas, whereby the heat transfer between the two glass plates is made difficult. After such a gas exchange, the bore in the web of the frame is sealed.
Lastly, cover strips, which cover the edge of the glass plates towards the outside, are also inserted into the frame. The window sash having the integrated insulating glass pane is thus finished.
For the most part, the known sashlite method is carried out manually. It is disadvantageous that the personnel costs are high and that quality deficiencies are unavoidable.
The instant invention has the object of remedying this.
SUMMARY OF THE PRESENT INVENTION
The method according to the invention is the subject matter of patent claim 1 . Advantageous refinements of the method are the subject matter of the subclaims.
The method according to the invention for assembling a window sash having an integrated insulating glass pane, which has a frame formed from plastic hollow profiles, said frame having an inner face, an outer face facing away from the inner face, and two flanks, which connect the inner face and the outer face to each other, wherein, on its inner face, the frame has two webs, which are parallel to each other, which constitute an all-around delimitation of the window opening of the window sash and are adhesively secured to two glass plates, which are held spaced apart by means of the two webs, takes place by
setting up the frame and the glass plates in a vertical position or in a position, which is inclined by a few degrees against the vertical, injecting by machine a paste-like adhesive compound, in which a moisture-binding material is embedded, into the space between the two webs, applying by machine a continuous line of a sealing compound onto the two outer faces of the webs, which face away from each other, orienting and holding by machine the two glass plates and the frame such that the two glass plates are located opposite each other so as to be congruent or almost congruent and so that the frame stands between the two glass plates and is oriented such that the glass plates and the edges of the two webs are centered towards each other, and pressing by machine the two glass plates against the webs facing them.
Preferably, the set-up of the frame and of the glass plates in vertical position or in a position, which is inclined by a few degrees against the vertical, also takes place machine-based.
This has considerable advantages:
The set-up of the frame and of the glass plates in vertical position or in a position, which is inclined by a few degrees against the vertical, and the carrying out of the operating steps, which lead to an assembled window sash, in such a position is a basic principle for a considerable rationalization of the assembly method. Personnel costs are saved. The operating steps, which have to be carried out, are independent on individual weaknesses and errors of the operating personnel. The quality of the window sashes is increased considerably and leads to a considerable lengthening of the operating life of the insulating glass pane in the window sash.
Preferably, the glass plates and the frame are set up on a horizontal conveyor and are secured against falling over. The processing on a horizontal conveyor is a basic principle for attaining a high productivity.
By means of horizontal conveying, the glass plates and the frame are preferably first brought into a position, in which they are located next to each other and in which the vertical edges of the glass plates and of the two webs of the frame are centered to each other in conveying direction, while the lower edges of the glass plates and of the frame are still located in a common plane. Only then the glass plates are lifted relative to the frame and the frame is lowered relative to the glass plates, until the horizontal edges of the glass plates and of the two webs of the frame are centered relative to each other. By this, the glass plates and the frame can be conveyed for all of the preparatory work and up to the first phase of the actual assembly with their lower edge being at the same height, even though the lower edge of the glass plates in the finished window sash must be located above the lower edge of the frame. This measure has the advantage that it facilitates the set-up of an automatically operating production line and shortens the processing times.
For centering the horizontal edges of the glass plates and of the webs of the frame relative to each other, the glass plates are preferably held in particular by means of suction devices, which act on the sides of the glass plates facing away from each other. The horizontal conveyor with the frame standing thereon can then be lowered and the height of the glass plates can then be oriented correctly to the frame for the window sash. The joining of the glass plates to the frame then takes place immediately by means of adhesion, so that orientation errors must no longer be feared.
During the lowering of the frame, the upper horizontal leg of the frame is caught with its inner face preferably by an adjusting device, which adjusts the position of the upper leg of the frame prior to pressing the glass plates against the webs of the frame facing them. With this measure, a disadvantageous sagging of the upper leg of the frame can be compensated in particular in the case of large-sized window sashes. Preferably, the glass plates are conveyed by means of a first horizontal conveyor via a turnout into a preparation station, which has three conveyor tracks, which are located parallel next to each other, which together can be displaced transversely and the two outer conveyor tracks of which are intended for the two glass plates and the middle conveyor track of which is intended for the frame of the window sash. Initially, the two outer conveyor tracks in the preparation station are consecutively brought into alignment with the conveyor track of the turnout, so that the two glass plates are conveyed on the two outer conveyor tracks of the preparation station. Preferably, the frame of the window sash is conveyed by means of a second horizontal conveyor, which is provided next to the first horizontal conveyor, only after this. A turnout is to connect the preparation station to the second horizontal conveyor, after it has supplied the two glass plates to the preparation station. The turnout then takes over the frame for a window sash and pivots back into alignment with the horizontal conveyor of the preparation station, which, by means of lateral displacement, brings its middle conveyor track in alignment with the conveyor track of the turnout or with the first horizontal conveyor, respectively, when the turnout has not yet been pivoted back into alignment with the first horizontal conveyor. The frame is then conveyed into the space between the two glass plates in the preparation station. This has the advantage that the sealing compound, which is typically applied onto the frame while being hot and which is preferably a reactive hotmelt, is brought in contact with the two glass plates within the shortest possible delay, so that a proper adhesion can be attained. From the preparation station, the two glass plates and the frame located therebetween, are together conveyed into an assembly station following the preparation station, in which they are centered to each other and the glass plates are pressed against the webs of the frame.
The first horizontal conveyor preferably connects a washing machine for the glass plates to the turnout. Arriving from the storage and being cut to size, the glass plates can thus be placed onto the production line. They are only washed at that location, so that the best conditions for also reaching the assembly station in a clean state are at hand.
A first station is preferably assigned to the second horizontal conveyor, wherein in the first station the paste-like adhesive compound, in which a moisture-binding material is embedded, is injected into the space between the two webs of the frame. A station, in which the continuous line of the sealing compound is applied onto the two outer faces of the webs facing away from each other, is also assigned to the second horizontal conveyor. Preferably, this takes place only after the paste-like adhesive compound, in which a moisture-binding material is embedded, has been applied. This also contributes to the time period between the application of the hot sealing compound to the final assembly of the window sash being as short as possible. For the same reason, the sealing compound is also simultaneously applied to the two webs.
The provision of two separate horizontal conveyors, which are connected to the preparation station and the assembly station by means of a turnout, also contributes to the time period between the application of the sealing compound to the actual assembly being as short as possible. In addition, the throughput through the production line is increased considerably.
When the insulating glass pane, which is integrated into the window sashes, is to contain a heavy gas, this is preferably attained in that one of the two glass plates is bent away from the frame prior to pressing against the webs of the frame, so that between the bent glass plates and the web located opposite thereto at least an access to the space between the two glass plates remains open after the glass plates have been pressed against the webs. A heavy gas can then be filled into the space between the glass plates through this access. The bending of the glass plate is then reversed, whereby the space between the two glass plates is closed tightly. This course of action can be automated in a particularly advantageous manner in the production line. It additionally has the advantage that considerably higher degrees of filling levels are attained with it than with the known sashlite method and that the danger of leakiness, which can lead to a loss of heavy gas and to a permeation of moisture, is smaller than in the case of the sashlite method, because in the case of the sashlite method a separate bore in the frame is provided for the gas filling, which bore must be closed subsequently. Such a bore is a permanent weak spot. According to the invention, such a bore is avoided.
Preferably, the one glass plate is bent away from the frame for the gas filling at two corners, which are located diagonally opposite each other. This is particularly advantageous for a quick filling process and for a high degree of filling.
Preferably, the one glass plate is bent with the help of suction devices, which are disposed on the outer face of the glass plate. This measure combines a gentle mode of operation with a desired fixation of the glass plate in predetermined position.
During the joining of the glass plates and of the frame, the glass plates are preferably pressed against the webs of the frame in that two frameworks, at which the suction devices are attached, are moved closer together. A defined path, by which the glass plates are displaced, is thus possible while being controlled well. In addition, the suction devices can contribute to a certain cushioning of the assembly process. During the assembly, the glass plates are preferably cushioned by means of thrust plates, which are acted upon by a compressed air cylinder and simultaneously act onto both glass plates in the area of the edge of the glass plates. In this manner, the compressed air cylinders can act as pneumatic spring, which prevents the breaking of glass and simultaneously provides for an optimal adhesive connection, in particular when a preselected pressure acts on the compressed air cylinders of the thrust plates for reaching an even pressing.
BRIEF DESCRIPTION OF THE DRAWINGS
An exemplary embodiment of the invention will be specified below by means of the enclosed drawings.
FIG. 1 shows, in top view, a first section of an assembly line for window sashes having an integrated insulating glass pane,
FIG. 2 shows a top view of a second section of the assembly line for window sashes having an integrated insulating glass pane,
FIG. 3 shows the preparation station from FIG. 1 in a transversal view,
FIG. 4 shows the preparation station from FIG. 3 in a side view with viewing direction parallel to the conveying direction,
FIG. 5 shows the section A from FIG. 4 as detail,
FIG. 6 shows section B of from FIG. 4 as detail,
FIG. 7 shows the assembly station from FIG. 1 in a transversal view,
FIG. 8 shows the assembly station in a side view parallel to the conveying direction,
FIG. 9 shows the rear part of the assembly station from FIG. 8 in a front view,
FIG. 10 shows the front part of the assembly station from FIG. 8 in a view seen from the rear part of the device,
FIG. 11 shows, as a detail, a transversal view onto the outlet end of the assembly station having a window frame and two glass plates, which are located parallel next to each other,
FIG. 12 shows, as detail C, a section of the rear part of the assembly station,
FIG. 13 shows, as detail D, a section of the front part of the assembly station,
FIG. 14 shows a first section from FIG. 13 ,
FIG. 15 shows a second section from FIG. 13 with changed adjustment,
FIGS. 16-18 show three subsequent phases of the assembly of the window sash, illustrated in the area of the upper edge thereof, and
FIG. 19 shows a section of a partially assembled window sash having a glass plate, which is bent away, during the gas exchange.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 show, in a schematic top view, a production line for window sashes or the wings of a door having an integrated insulating glass pane. To simplify matters, only window sashes are discussed in this patent application. However, the same applies to the wings of a door. Wings of a door are to be included in the invention. The term “sash” is to comprise displaceable as well as pivotable sashes.
The illustration in FIG. 2 connects to the right end of the illustration in FIG. 1 .
The production line has a first horizontal conveyor 1 and a second horizontal conveyor 2 , which runs transversely thereto and which lead into a horizontally conveying turnout 4 , to which a third horizontal conveyor 3 connects, which is arranged in alignment with the first horizontal conveyor 1 . The first horizontal conveyor 1 consists of a plurality of sections, starting with a section 5 , to which the individual glass plates 52 , 53 are placed one after the other, of a section, which leads through a machine 6 for washing and drying the glass plates, and of two sections 7 and 8 , which serve the intermediate transport and, if necessary, also for retaining the glass plates 52 , 53 . In section 7 , it is furthermore also possible to check whether the washed glass plates are actually clean. In sections 5 to 8 , the first horizontal conveyor 1 has a horizontal row of synchronously driven rollers 9 , which are located in the sections 5 , 7 and 8 at the lower edge of a support wall 10 , which is inclined backwards against the vertical by few degrees, e.g. by 6°, and which is preferably embodied as an air cushion wall. The glass plates are conveyed while standing on the rollers 9 and leaning against the support wall 10 . The glass plates are supported in the washing and drying machine 6 in an inherently known manner by means of an arrangement of washing brushes and rollers.
The second horizontal conveyor 2 also has a plurality of sections 11 , 12 , 13 , 14 and 15 , in which provision is made in each case for a continuous conveyor belt 16 comprising a horizontally running upper run at the lower edge of a support wall 17 , which is inclined backwards out of the vertical position at the same angle as the support wall 10 . Advantageously, the upper run is arranged at a right angle to the support wall 10 and is thus also inclined backwards by a few degrees. The second horizontal conveyor 2 serves to convey rectangular or square frames 51 (see FIG. 1 ), which are formed from plastic hollow profiles. They are placed onto the conveyor belt 16 with one of their legs and are leaned against the support wall 17 , in which strips, which are preferably provided with bristles, in particular with soft bristles, for reducing the friction, are inserted or adhesively secured. A row of free-running guide rollers 18 , which are partially located beneath the support wall 17 , but which project beyond it and which in each case have an axis, which runs vertically to the upper run of the conveyor belt 16 , is located closely above the conveyor belt 16 . Provision is preferably made at a distance to the support wall 17 for a further row of support rollers 19 , the height of which can be adjusted and which, if necessary, serve to prevent a tilting of the frame standing on the conveyor belt 16 .
In section 11 of the second horizontal conveyor 2 , the frames formed from the plastic hollow profiles 21 are placed onto the horizontal conveyor 2 .
A system 20 is assigned to the section 12 of the second horizontal conveyor 2 , which system 20 serves to inject an adhesive compound, in which a desiccant is embedded, into the space between two webs of the plastic hollow profile, from which the frame 51 for the window sash is formed. An example of such a plastic hollow profile is illustrated in cross section in FIGS. 16 to 19 . The illustrated plastic hollow profile 21 has a plane outer face 22 , a structured inner face 23 , two flanks 24 and 25 and several hollow chambers. Two webs 26 and 27 , which are parallel to the flanks 24 and 25 and parallel to each other and the space between which is open towards the inner face of the frame 51 , are located on the inner face 23 . The webs 26 , 27 are angled at their free end and thus form a projection 28 , against which the glass plates 52 , 53 can hit, for which the webs 26 and 27 serve as spacers, see FIG. 18 . An adhesive compound 29 , in which a desiccant is embedded, is injected into the space between the webs 26 and 27 by means of the system 20 . A polyisobutylene is particularly suitable as adhesive compound 29 and molecular sieves are particularly suitable as desiccant. Advantageously, the adhesive compound 29 is injected by means of a nozzle 30 , which can be displaced up and down parallel to the support wall 17 and which can be rotated about an axis, which is perpendicular to the support wall 17 . For injecting the adhesive compound 29 into the space between the vertical webs 28 , the nozzle 30 is moved up or down, respectively, while the frame 51 formed from the hollow profile 21 rests. The adhesive compound 29 is injected into the space between the horizontal webs 26 and 27 , while the frame 51 formed from the hollow profile 21 is conveyed back or forth horizontally, respectively, and the nozzle 30 rests.
A system 31 for applying a line 35 of a sealing compound to the faces of the webs 26 and 27 , which face away from each other, is assigned to the section 14 of the second horizontal conveyor 2 . For this purpose, a first nozzle 32 is located in front of the support wall 17 and a second nozzle 33 is located behind the support wall 17 , from where it can engage through the support wall 17 through a slot 34 therein, which runs from the bottom to the top. The nozzles 32 and 33 can be moved in the same manner as the nozzle 30 and they are moved and activated synchronously, so that they simultaneously apply the sealing compound to the outer face of the two webs 26 and 27 . The line 35 of the sealing compound is illustrated in FIGS. 16 to 18 .
The sections 13 and 15 of the second horizontal conveyor 2 serve for the intermediate transport of the frames. If necessary, lattice bars can be inserted into the frame 51 in section 13 .
The section of the production line illustrated in FIG. 1 starts with the turnout 4 , which can be pivoted back and forth between the two positions illustrated in FIG. 1 . The turnout 4 has a horizontal conveyor with a design, which is the same as or which is similar to one of the sections of the second horizontal conveyor 2 and which can thus be considered to be a pivotable continuation of the second horizontal conveyor 2 . In the position, in which the turnout 4 is aligned with the first horizontal conveyor 1 , it can take over the glass plates 52 , 53 , which have been conveyed to that location, and can transfer them into a preparation station 36 . In the position, in which the turnout 4 is aligned with the second horizontal conveyor 2 , it can take over a frame 51 for the window sash from said second horizontal conveyor 2 . To be able to transfer the frame 51 into the preparation station 36 , the turnout 4 , however, must initially be pivoted into that position, in which it is aligned with the preparation station 36 and the first horizontal conveyor 1 .
The preparation station 36 is illustrated in FIGS. 3 to 6 . It has a frame-shaped framework 39 on a subframe 37 , which has two rails 38 , which are inclined backwards. On its front face, the framework 39 has two posts 40 , which are inclined backwards and which project upwards at a right angle to the rails 38 . The rails 38 run at a right angle to the conveying direction of the first and third horizontal conveyor 1 or 3 , respectively. The posts 40 are inclined backwards at the same angle as the support walls 10 . An arrangement of three horizontal beams 41 , 42 and 43 is supported at the posts 40 so as to be displaceable up and down, so that the height of the beams 41 , 42 and 43 can be adjusted. The three beams 41 , 42 and 43 in each case support a horizontal row of free-running support rollers 44 , which can be rotated about axes, which run parallel to the posts 40 . A three-track horizontal conveyor 45 , which encompasses a horizontal support 46 for three continuous conveyor belts 47 , 48 and 49 , the upper runs of which are arranged parallel to each other at a distance and which are inclined backwards at the same angle as the posts 40 , is attached to the framework 39 in the lower area thereof. The two outer conveyor belts 47 , 49 serve to convey glass plates 52 , 53 , whereas the middle conveyor belt 48 , which is wider than the outer conveyor belts 47 and 49 , is intended to convey a frame 51 for a window sash. The conveyor belts 47 to 49 can be driven separately. On the support, free-running support rollers 50 are arranged on both sides of the conveyor belts 47 and 49 . They serve the purpose of guiding the lower edge of the glass plates and of the frame for the window sash. The axes thereof run parallel to the axes of the rollers 44 , which are attached to the beams 41 , 42 and 43 .
By transversely displacing the framework 39 on the rails 38 of the subframe 37 , each of the three conveyor belts 47 , 48 and 49 can be brought into alignment with the horizontal conveyor of the turnout 4 . In the position illustrated in FIG. 1 , the turnout 4 can transfer a frame 51 for a window sash to the middle conveyor belt 48 ; the support rollers 18 of the turnout 4 are aligned with the support rollers 50 , which are arranged between the rear conveyor belt 49 and the middle conveyor belt 48 , and which are inclined backwards at the same angle as the posts 40 . To transfer a glass plate 53 to the rear conveyor belt 49 , the latter is positioned by transversely displacing the support 46 such that the support rollers 50 arranged behind the conveyor belt 49 are aligned with the support rollers 18 in the turnout 4 . To be able to transfer a glass plate 52 to the front conveyor belt 47 , the latter is positioned by transversely displacing the support 46 such that the support rollers 50 arranged between the front conveyor belt 47 and the middle conveyor belt 48 are aligned with the support rollers 18 in the turnout 4 .
In the preparation station 36 , the frame 51 and the two glass plates 52 and 53 are preferably positioned such that the front vertical edges thereof are located approximately next to each other and are adjacent to the subsequent assembly station 54 .
The assembly station 54 is illustrated in FIGS. 7 to 15 . It has a subframe 55 comprising rails 56 , the incline of which corresponds to the incline of the rails 38 in the preparation station 36 . A framework 57 is attached to the subframe 55 , which framework 57 is similar to the framework 39 of the preparation station 36 and, as does the latter, has an arrangement of three beams 58 , 59 , and 60 , to which a horizontal row of support rollers 61 is attached in each case, the axes of which run approximately vertically, namely at a right angle to the rails 56 . As in the case of the arrangement of the beams 41 to 43 in the preparation station 36 , the arrangement of the beams 58 to 60 is attached at the posts of the framework 57 in a height-adjustable manner. In contrast to the displaceable framework 39 in the preparation station 36 , the framework 57 , however, is fixed on the subframe 55 so as not to be able to be displaced. A three-track horizontal conveyor 62 , the design of which corresponds to the three-track horizontal conveyor 45 in the preparation station 36 , is attached to the subframe 55 so as to be height-adjustable.
A front framework 63 , which can be displaced on a pair of rails 56 , is arranged in front of the stationary framework 57 . A rear framework 64 , which can also be displaced on a pair of rails 56 , is arranged behind the stationary framework 57 . FIG. 2 shows a view of the rear framework 64 . At their lower ends, two lateral posts 65 of the rear framework 64 have undercut guide parts 66 , which engage around the rails 56 . At the posts 65 , a horizontal traverse 67 is attached, which can be displaced up and down at the post 65 by means of gear belts 68 , which are driven by a motor 69 . Thrust plates 70 are attached to the traverse 67 , which thrust plates 70 can be activated by means of pressure medium cylinders 71 , in particular by means of pneumatic cylinders, which are illustrated in FIGS. 7 and 8 , but which are not visible in FIG. 9 , because they are located behind the traverse 67 . Provision is made above each thrust plate 70 for an adjusting device 72 , see FIG. 16 , consisting of a pneumatic cylinder 73 , the piston rod 74 of which has a head 75 , to which a retractable bar 76 , which is guided parallel to the piston rod 74 , is attached. The adjusting device 72 serves the purpose of positioning the upper leg of the frame 51 and to remove a possible sagging of the upper leg of the frame 51 , see FIGS. 16 to 18 .
Thrust plates 70 , which are also individually activated by means of pressure medium cylinders, and additionally a row of suction devices 78 are attached to a lower traverse 77 of the rear framework 64 . A further suction device 78 is attached to the horizontal traverse 68 . The suction devices 78 as well as the thrust plates 70 can be displaced individually by means of pressure medium cylinders 89 , in particular by means of pneumatic cylinders. An upright traverse 80 , which is parallel to the posts 65 , is attached to the lower traverse 77 and to an upper traverse 79 of the rear framework 64 , so as to be displaceable horizontally. The upright traverse 80 crosses the horizontal traverse 67 and is arranged behind the latter. The displacement of the upright traverse 80 takes place in the same manner as in the case of the horizontal traverse 67 by means of two gear belts 81 , which are driven by a motor 82 . Further thrust plates 70 and 70 a , which can also be activated individually by means of pressure medium cylinders, are attached to the upright traverse 80 and to the post 65 , which is parallel thereto. Most of the thrust plates 70 are attached to the traverses 67 , 77 and 80 as well as to the post 65 , in each case on a slide 83 , which drags along smaller thrust plates 70 a , which are attached to a slidable lattice grate 84 , whereby the distance of the thrust plates 70 , 70 a , which are connected by the slidable lattice grate 84 , from each other changes. The length adjustment effected by the slidable lattice grate 84 allows for the position of the thrust plates 70 and 70 a to be optimally adapted to the height and width of the frames 51 . The displaceability of the traverses 67 and 80 also serves for the adaptation to height and width of the frames 51 for the window sashes.
FIG. 9 furthermore shows two suction devices 85 and 86 , which are larger than the suction device 78 . In the view of FIG. 9 , the lower suction device 85 is located in the left lower corner of the field defined by the traverses 67 , 77 , 68 and by the post 65 and is attached to the lower traverse 77 . The upper suction device 86 is located in the diagonally opposite corner of this field. While the lower suction device 85 can only be moved back and forth and otherwise maintains its position at the lower traverse 77 , the upper suction device 86 can additionally follow the movements of the traverses 67 and 80 , so that it maintains its position in the corner of the field, which is determined by the position of the traverses 67 and 80 . A glass plate 53 , which is held by the suction devices 78 in the field, which the traverses 76 , 70 , 68 and the post 65 span, can be bent backwards at two diagonally opposite corners by means of these suction devices 85 and 86 . In addition, the larger suction devices 85 , 86 contribute to the fixing of the glass plates 52 , 53 , which must take place before the three-track horizontal conveyor 62 can be lowered. The larger suction devices 85 and 86 can be displaced by means of pressure medium cylinders, in particular by means of pneumatic cylinders 89 in the same manner as the smaller suction devices 78 .
With the help of the larger suction devices 85 and 86 , an access to the space between the two glass plates 52 , 53 of the window sash can be held open temporarily during the assembly of a window sash for the purposes of a gas exchange. Air in the space between the glass plates 52 and 53 is replaced with heavy gas during the gas exchange. Advantageously, the heavy gas is supplied in the area of the lower corner in the vicinity of the lower suction device 85 and displaces the air through the opening in the area of the upper suction device 86 located diagonally opposite thereto. So that the heavy gas does not discharge again through the access, which is held open by the lower suction device 85 , provision is made at that location for a two-legged seal 87 , which covers the gap between the frame 51 and the rear glass plate 53 in the lower corner of the frame 51 and thus seals the access to the space between the glass plates 52 , 53 . The seal 87 can be a molded part, e.g. consisting of a foam rubber or the like. A feed line 88 for the heavy gas, which is to be supplied, extends through the seal 87 . The end section of the feed line 88 , which is guided through the seal 87 , is preferably a porous pipe piece, the end of which is closed, which can consist, e.g., of a sintered plastic, from which the heavy gas escapes in a diffuse manner, flows into the space between the glass plates 52 , 53 and displaces the air at that location upwards such that the air leaves the space via the opening provided by the upper suction device 86 .
FIG. 10 shows a view of the front framework 63 , which corresponds to the view of FIG. 9 , which is arranged in front of the three-track horizontal conveyor 62 in the assembly station. This front framework 63 is substantially a mirror image of the rear framework 64 , so that reference can be made to the description of the rear framework 64 with reference to the details. The front framework 63 , however, does not have the larger suction device 85 , the seal 87 and also not a feed line 88 for a heavy gas.
The window sashes are assembled in the described production line according to the following method:
The two glass plates 52 and 53 required for a window sash are placed onto section 5 of the first horizontal conveyor 1 . The frame 51 required for the window sash, which is pre-manufactured from plastic hollow profiles, is placed onto section 11 of the second horizontal conveyor 2 . The glass plates 52 and 53 are conveyed consecutively through the washing and drying machine 6 , can be checked for cleanliness in section 7 of the first horizontal conveyor 1 , reach section 8 of the first horizontal conveyor 1 , on which they can be stored, if necessary, when the turnout 4 or the preparation station 36 following it should not yet be ready. The turnout 4 is ready for the glass plates 52 and 53 when it is aligned with the first horizontal conveyor 1 and when it is empty. In this case, the two glass plates 52 and 53 are conveyed consecutively onto the turnout 4 . When the preparation station 36 is ready, it is positioned by means of lateral displacement such that either the support rollers 50 arranged behind the rear conveyor belt 49 or the support rollers 50 arranged between the front conveyor belt 47 and the middle conveyor belt 48 , are aligned with the support rollers 18 of the turnout 4 . In the last-mentioned case, the first glass plate 52 is then conveyed on the front conveyor belt 47 , is conveyed by it just in front of the outlet end of the preparation station 36 and is stopped there. By transversely displacing the framework 39 , the conveyor track intended for the second glass plate 53 with the rear conveyor belt 49 is then displaced to be aligned with the turnout 4 and the turnout 4 conveys the second glass plate 53 to the rear conveyor belt 49 , which conveys it up to the outlet end of the preparation station 36 and stops it there. The three-track horizontal conveyor 62 is subsequently positioned such that its middle conveyor track comprising the wider conveyor belt 48 is aligned with the first horizontal conveyor 1 .
Overlapping in time with the passage of the two glass plates 52 and 53 through the first horizontal conveyor 1 , the adhesive compound, in which a desiccant is embedded, is injected into the space between the two webs 26 and 27 of the frame 51 on the second horizontal conveyor 2 in section 12 thereof. If desired, it is possible to insert lattice bars into the frame 51 in section 13 of the second horizontal conveyor 2 . In the subsequent section 14 of the second horizontal conveyor 2 , a continuous line 35 of a sealing compound is applied to the outer face of the two webs 26 and 27 without interruption. In the subsequent section 15 of the second horizontal conveyor 2 , the frame 51 , which is prepared and coated in this manner, can be stored until the turnout 4 is free and is pivoted into its position, which is aligned with the second horizontal conveyor 2 . The frame 51 is subsequently conveyed onto the turnout 4 . As soon as this has taken place, the turnout 4 pivots back into alignment with the first horizontal conveyor 1 . If this has not taken place until then, by transversely displacing on the subframe 37 , the framework 39 of the preparation station 36 with the line of support rollers 50 arranged between the middle conveyor belt 48 and the rear conveyor belt 49 is next brought into alignment with the support rollers 18 in the turnout 4 . As soon as this has taken place, the frame 51 is conveyed onto the middle conveyor belt 48 and is further conveyed by it to the outlet end of the preparation station 36 . If the subsequent assembly station 54 is ready for take-up, the frame 51 can run into the assembly station 54 without stopping and the two glass plates 52 and 53 are simultaneously conveyed out of the preparation station 36 into the assembly station 54 . In the event, however, that the assembly station 54 is not yet ready, the frame 51 is stopped in the preparation station 36 . The frame 51 and the glass plates 52 and 53 have then assumed the position illustrated in FIG. 1 . As soon as the assembly station 54 is ready, the frame 51 and the two glass plates 52 and 53 are simultaneously conveyed into the assembly station 54 and are moved into the proximity of the outlet end thereof, where they are stopped—e.g. controlled by means of position sensors—such that the upright edges of the two glass plates 52 , 53 in conveying direction are centered towards the upright edges of the two webs 26 and 27 of the frame 51 . Due to the fact that the upper runs of the conveyor belts 47 , 48 and 49 are located in a common plane, the height of the glass plates 52 and 53 is not yet correctly oriented towards the height, which they must assume in the frame 51 , see FIG. 11 .
To attain this, the suction devices 78 provided in the two frameworks 63 and 64 of the assembly station 54 are pushed ahead up to the adjacent glass plate 52 or 53 , respectively, by activating pneumatic cylinders 89 , at the piston rod of which in each case a suction device 78 is attached and activated, so that the two glass plates are aspirated and are fixed in their position. Only those suction devices 78 , which are required for the length and height of the respective glass plates 52 and 53 , are pushed forward and activated. The dimensions of the glass plates 52 , 53 can be known from the production planning and can be provided by the control of the assembly station 54 , or they can be determined by position sensors, which are provided in the assembly device 54 . In this manner, the traverses 67 and 80 can be automatically adjusted to the current dimensions of the glass plates 52 , 53 or to the corresponding frame 51 , respectively. The adjustment of the traverses 67 and 80 to the dimensions of the current frame 51 includes the orientation of the thrust plates 70 , 70 a , for the purpose of which the slides 83 are displaced into such a position, in which the thrust plates 70 , 70 a are located opposite to the edge of the glass plates 52 and 53 at distances, which are as even as possible. Only suction devices 78 are activated, which are located in the field, which, in terms of FIG. 9 , is located on the bottom left and is defined by the traverses 66 , 67 and 80 as well as by the post 65 . In addition, the larger suction devices 85 and 86 are pushed forward against the glass plates 52 and 53 and are activated.
Simultaneously with the suction devices 78 , the thrust plates 70 , 70 a are also extended by their pneumatic cylinders 71 and come in contact to the glass plates 52 , 53 , see FIG. 16 . In addition, the adjusting device 72 is now activated. For this purpose, the bars 76 are extended by activating the pneumatic cylinders 73 , so that they reach underneath the flanks 24 and 25 of the upper leg of the frame 51 , see FIG. 16 .
The three-track horizontal conveyor 62 can now be lowered in the assembly station 54 . Through this, the upper leg of the frame 51 is placed onto the bars 76 , see FIG. 17 , and a possible sagging of the upper leg of the frame 51 is overcome. The three-track horizontal conveyor 62 is lowered until the horizontal edges of the glass plates 52 and 53 are centered on the horizontal edges of the webs 26 and 27 . The lines 35 of the sealing compound are now located opposite to the glass plates 52 , 53 close to the edge thereof.
Next, the beams 58 , 59 and 60 are lifted, so that the support rollers 61 disengage from the glass plates 52 , 53 . The front framework 63 and the rear framework 64 are then both moved towards each other, whereby the glass plates 52 and 53 press against the line 35 of the sealing compound, which is located on the webs 26 and 27 . The movement of the frameworks 63 and 64 is thereby cushioned by the pneumatic cylinders 71 of the thrust plates 70 , 70 a , which ensure a pressing of the glass plates 52 , 53 against the webs 26 and 27 of the frame 51 at a predetermined pressure, see FIG. 18 .
The window sash is thus assembled. The pneumatic cylinders of the thrust plates 70 , 70 a and of the adjusting device 72 retract their piston rods again, the suction devices 78 , 85 and 86 are deactivated and pulled back, the three-track horizontal conveyor 62 is lifted back to the original height, which corresponds to the height of the horizontal conveyor in the preparation station 36 , and the window sash is conveyed out of the assembly station 54 onto an outlet conveyor 90 . If necessary, cover strips, which cover the edge of the glass plates 52 and 53 , can be inserted here into the frame 51 in a manner, which is known per se.
In the event that the insulating glass pane, which is integrated into the window sash, is to be filled with a heavy gas, this takes place in that, prior to the pressing of the one glass plate 53 against the frame 51 , the rear glass plate 53 is bent outwards at diagonally opposite corners by means of the suction devices 85 and 86 —see FIG. 19 —wherein the heavy gas is introduced through the access, which has been established by means of the suction device 85 and air is displaced from the space between the two glass plates 52 and 53 through the opening, which has been established by means of the suction device 86 . Once a sufficiently high filling degree of the heavy gas has been reached, the suction devices 85 and 86 are deactivated, whereby the openings close easily due to the elastic resilience of the glass plates 52 and 53 and are closed by the impact of the pneumatically activated thrust plates 70 , 70 a . FIG. 19 shows in detail the access 91 at a lower corner of the window sash with the attached seal 87 and a section of the porous feed line 88 , through which the heavy gas is supplied, and a part of the elastomeric suction plate of the suction device 85 between the seal 87 and the glass plate 53 .
What has been described above are preferred aspects of the present invention. It is of course not possible to describe every conceivable combination of components or methodologies for purposes of describing the present invention, but one of ordinary skill in the art will recognize that many further combinations and permutations of the present invention are possible. Accordingly, the present invention is intended to embrace all such alterations, combinations, modifications, and variations that fall within the spirit and scope of the appended claims. | A method for assembling a window sash having an integrated insulating glass pane. The window sash has a frame formed from plastic hollow profile sections. The frame has an inner face, an outer face facing away from the inner face, and two flanks that connect the inner face and the outer face to each other. On the inner face thereof, the frame has two webs parallel to each other, which constitute an all-round delimitation of the window opening of the window sash and are adhesively secured to two glass panes which are held spaced apart by the two webs. | 4 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part application of pending U.S. Ser. No. 349,000, filed May 8, 1989, now U.S. Pat. No. 5,049,134.
This invention pertains to the art of pumps and more particularly to electrically driven pumps capable for use as heart or blood pumps, or ventricular assist devices.
The invention is applicable to a pump for the pumping of blood of a living person, or animal, to replace or assist the pumping function of the biologic heart. It is capable of being sized and designed to fit inside a pumping chamber of a human heart, e.g. dimensioned on the order of a few inches . However, certain aspects of the invention could be readily configured for use in other environments than a blood pump wherein the presence of a shaft seal or long fluid residence times in the pump would be detrimental to the application.
In the preferred environment, conventional continuous flow rotodynamic blood pumps, which includes centrifugal blood pumps, axial flow blood pumps, or nonpulsatile blood pumps, have suffered from a number of problems. One major difficulty has been the presence of a shaft seal. Loss of blood from the circulatory system, and/or introduction of material of damaging types or quantities into the circulatory system must be prevented. Because of the intended use as life support for a human being, long life and utter reliability are key design goals. Using a contact type seal or fluid purged seal as the shaft seal results in significant difficulties meeting these objectives.
Most commercially available blood pumps, as exemplified by U.S. Pat. Nos. 4,135,253 to Reich, et al., 4,625,712 to Wampler, 3,647,324 to Rafferty, et al., or 4,589,822 to Clausen et al., have a blood pumping impeller mounted on a shaft which penetrates a side wall of the pumping cavity by means of a shaft seal. On the non-blood side of the seal, or drive compartment, is a motor or drive magnet, operating in air or a biocompatible fluid, which rotates the impeller via the shaft. A very common cause of failure of such prior known blood pumps is the eventual leakage of the seal about the shaft which either permits blood to enter into the drive compartment, excessive fluid leakage from the non-blood side into the blood, or both.
Other blood pump structures have been proposed to overcome the problems of blood pump shaft seals. Moise has a non-contacting housing-shaft interface with micron sized clearances that unfortunately introduce significant problems. Attempting to maintain these close dimensional tolerances clearly becomes a manufacturing problem. Additionally, there is a risk of blood leakage if the supply of purge fluid to the non-blood seal of the pump is interrupted.
Dorman U.S. Pat. No. 4,927,407 suggests using a constant flow pump such as a dynamic perfusion pump to supply a continuous, controlled flow of purge fluid to the seal. The purge fluid flow maintains the seal out of contact with the shaft. Unfortunately, this adds significant complication to the system because of the need for another active control pump and, even then, still requires a purge fluid for normal operation.
Alternatively, it has been suggested to magnetically suspend the impeller in three dimensions. This eliminates the need to breach the pump walls with a shaft to the impeller. Bramm, et al. and Moise generally illustrate this approach. However, at best this is a complex system because of its three dimensional nature, and is not presently believed to be commercially feasible.
Still other blood pumps have eliminated a penetrating shaft and accompanying seal by magnetically coupling the pump to a prime mover through a wall of the housing. Dorman U.S. Pat. No. 3,608,088 is an example of one such arrangement from the blood pump field. Although these eliminate leakage, they may amplify other problems also present in shaft sealed designs.
For example, high shear stresses around the seal, or around radial and axial bearings, can damage blood if the loads and shear stresses are not very low. Axial magnetic coupling, such as exemplified by Dorman, particularly creates an axial load which must be reacted or countered. Both shear and mechanical friction forces can produce heat that injures susceptible media. With blood, heat produced from the shear and friction forces can also promote deposition, including protein buildup, as well as a conventional clot.
Residence time is also a factor in handling some fluids such as blood. The amount of shear that blood can tolerate is a function of exposure time. Blood coagulation, leading to clots and emboli, also requires a finite time to occur. Thus many pump structures and principles derived from pumps in other fields are not suitable in the blood pump environment since they include relatively stagnant areas where the blood can settle out, react, decompose, or otherwise respond according to the environment and their sensitivity.
Some alternate pump design proposals employ a counter-impeller to prevent backflow along the shaft. This is particularly well known in other pump environments, i.e., non-blood pumps where the dynamic action of a counter-impeller provides a back flow along the shaft. These arrangements hold pumped fluid for long periods in the expeller, thus exposing the pumped fluid to shear. Therefore, these structures are not feasible for use as blood pumps because of all the problems described above associated with long residence times and shear. Further, these arrangements could accelerate leakage into the system if the second impeller discharges its prime of pumped fluid. Even further, these pump arrangements still require additional sealing in order to prevent fluid loss at static or low speed conditions.
The present invention contemplates a new and improved device which overcomes all of the above discussed problems and others to provide a new blood pump.
BRIEF SUMMARY OF THE INVENTION
According to the present invention, there is provided a new rotodynamic blood pump which is capable of being implanted in a human body to assist or replace the pumping functions of the heart. The pump includes a rotor rotatably received in a pump chamber. The rotor is suspended in the chamber by fluid bearing means, preferably provided by an axial extension of the housing. Means for renewing fluid contact with all wetted surfaces of the chamber is also provided.
According to a more limited aspect of the invention, the pump comprises a housing having inlet and outlet fluid passages communicating with a pump chamber. An end wall extends axially into the chamber and defines a journal surface to support radial loads. An annular rotating assembly, or shaftless rotor, is received in the pump chamber and is driven by a drive means having a drive element and a driven element for selective rotation relative to the housing. The rotor includes both pumping blades and the driven element of the drive means. The annular rotor cooperates with the axial extension to define two fluid passages. The primary fluid passage leads from the inlet to the outlet, while the second passage permits a continuous flow to be delivered to otherwise potentially stagnant areas of the pump. Further, at least a portion of this second passage is narrowed to form a radial fluid bearing.
According to another aspect of the invention, the rotor is radially magnetically coupled to the drive element of the drive means. The drive means has a central cylindrical element and a surrounding annular element, either one of which is the drive element of the system. Further, the axial running position of the rotor is substantially maintained by the reaction of the drive means magnetic forces to the applied pressure forces on the rotor. Means for limiting the motion of the rotor is also provided.
According to yet another aspect of the invention, a predetermined radial offset is provided between the axes of the rotor and the drive element. This results in a magnetic imbalance force of known magnitude and direction.
According to a still further aspect of the invention, the fluid bearing means includes a groove to increase fluid flow through the bearing means.
According to still another aspect of the present invention, the rotor includes first and second sets of blades. The first blade set has substantially more pumping capacity than the second blade set and defines an impeller or main stage primarily urging the fluid from the inlet to the outlet. The second blade set controls and assists fluid flow through the second passage. Additionally, the second blade set produces a pressure distribution which counteracts that produced by the first blade set, reducing the net force to be reacted in the magnetic coupling.
According to another, yet more limited aspect of the present invention, the rotor includes openings between the primary and secondary flow passages permitting fluid exchange therebetween.
One benefit obtained from the present invention is a sealless pump having a single moving part and improved durability.
Another benefit is the provision of a pump that eliminates flow stasis areas, and maintains surface washing throughout the pump.
A further benefit of the invention is eliminating significant mechanical axial thrust contacts.
Yet another benefit of the invention is a means to stabilize the position and operation of a fluid bearing.
Still other benefits and advantages of the subject invention will become apparent to those skilled in the art upon a reading and understanding of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take physical form in certain parts and arrangements of parts, preferred embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:
FIG. 1 is a side elevational view of a blood pump formed in accordance with the present invention and particularly showing the pump housing and inlet and outlet passageways;
FIG. 2 is a left-hand end view taken generally along the lines 2--2 of FIG. 1;
FIG. 3 is an enlarged, longitudinal cross-sectional view of a first preferred embodiment of the subject invention;
FIG. 4 is a cross-sectional view taken generally along lines 4--4 of FIG. 3;
FIG. 5 is a cross-sectional view taken generally along lines 5--5 of FIG. 3;
FIG. 6 is a schematic illustration of the electromagnetic reaction between a stator and operating rotor in the present invention and is intended to demonstrate the preservation of the desired axial running position of the impeller relative to the housing;
FIG. 7 is a schematic cross-sectional view taken along line 7--7 of FIG. 3 particularly illustrating the predetermined radial offset of pump components;
FIG. 8 is a longitudinal cross-sectional view of an alternate embodiment of the invention; and
FIG. 9 is another embodiment of the invention showing an alternate version of the drive means.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings wherein the showings are for purposes of illustrating the preferred embodiments of the invention only and not for purposes of limiting same, the FIGURES show a pump 10 comprised of a housing 12, and having an inlet 14 and an outlet 16. While the drawings show an axial inlet, and a radial or tangential outlet, these are not essential features of the invention. In the blood application, the pump can be sized for implantation within a living body, and is preferably employed as an assist device for humans. It is to be noted that the pump can be sized so as to even be implantable within a heart chamber, avoiding the substantial problems of larger devices.
With particular reference to FIGS. 1-3, the housing 12 is shown to be more particularly comprised of a rotor portion 18 and a drive housing or outlet portion 20, which in this particular embodiment partially houses the rotor as well as the drive means. Since in the preferred embodiments the pump is adapted for implantation in the living body, the housing portions are formed from a suitable, biocompatible material such as polished titanium. The housing portions 18, 20 are fastened together with conventional fastening devices 22 and sealed with a conventional sealing device such as an O-ring 24. The O-ring is positioned in an area of overlapping engagement 26 which has been made an interference fit or bonded so as to be gap free.
The housing portion 20 incorporates an axial extension 30 protruding from end wall 32. The axial extension receives motor windings 34 and lamination assembly or ferrous stack 36 of an electric motor 38. The motor is retained in the outlet housing portion by cover 42 and a fastener such as screw 44. The cover is sealed to the outlet housing portion with 0-ring 46. The extension 30 protrudes a substantial dimension from the end wall, in fact, extending into the rotor housing portion and toward the inlet 14 This arrangement provides a generally annular pump chamber 48.
Received over the housing extension 30 is an annular rotor 60. The rotor includes an encapsulated permanent magnetic assembly 62, and first and second impeller blade sets 64, 66. There is no interconnecting shaft between the motor and impeller, i.e. a shaftless rotor. Further, a shaft seal between the motor and the impeller is eliminated, thus obviating many of the problems discussed above in prior art structures. In the preferred embodiment, the permanent magnet assembly 62 in the pump rotor 60 radially couples the rotor to the motor stator (stack and windings) through the non-magnetic wall of housing extension 30. It should be noted that this arrangement is essentially an inversion of the usual commercial motor arrangement, because the rotating element of the motor, i.e., the permanent magnetic assembly 62, is larger in diameter and encircles the stationary element, i.e., the stator 34, 36. This electric motor serves as the means for driving this embodiment of the invention insofar as it serves to create rotational motion of the pump rotor relative to the housing. The stator assembly is the drive element and the permanent magnet assembly the driven element of this version of a drive means.
With particular reference to FIGS. 3 and 4, the first or primary impeller blade set 64 includes a plurality of mixed flow impeller blades. Radial flow or axial flow blade arrangements could also be encompassed within the scope of the invention. The impeller shown is a three-bladed variable lead screw. The secondary impeller blade set 66 is comprised of a plurality of radial flow impeller blades in this design embodiment.
The placement of rotor 60 in the housing 12 defines a continuous, first fluid passage 70 between the rotor 60 and the interior wall of the housing, which traverses from the inlet 14 to the annular output collector 72 of the pump chamber. A continuous second passage fluid passage 74 is formed between the housing extension 30 and the inside diameter of pump rotor 60. The second 74 has a generally large clearance, perhaps 0.020-0.030 inch, compared to the flow to be passed, but narrows to approximately 0.003-0.005 inch at opposite ends of the rotor to define first and second fluid bearings 80, 82 during operation of the pump. The first bearing 80 is located at the terminal end 84 of the portion of the motor housing extension 30 facing the inlet 14. This terminal end portion 84 has a generally cone-like configuration and includes one or more extended helical grooves 86 to increase the lubricating and cooling flow through the fluid bearing 80. The second fluid bearing 82 similarly has a helically configured grooving 88 on the outer wall of the motor housing extension 30 to increase the bearing wash flow.
For improved pumping that avoids fluid damage or deposition due to sluggish or non-existing flow velocities through second passage 74, a continuous washing flow is required. The second set of impeller blades 66 scavenges blood from the second passage, discharging it to the collector 72. To prevent excessive pressure drop, a plurality of circumferentially spaced openings 90 extend generally radially between the first and second fluid passages to permit fluid to flow from the first to the second passage. Under the action of the pressure rise produced by the first blade set 64, flow traverses from openings 90 to impeller inlet 14, along passage 74. The second blade set also draws fluid from openings 90, through bearing 82, past end wall 32 and discharges the fluid into the collector 72.
With particular reference to FIG. 4, it may be seen that the annular collector chamber 72 can be spirally offset relative to the generally circular dimension of the rotor 60. Such a configuration is generally conventional for the volume of a rotodynamic pump, but the present invention may also be used with other forms of discharge collector.
Because the annular pump rotor 60 is freely received in the housing 12, it is important that its motion be controlled so that damage to the pumped fluid or the mechanical components does not result in close clearance areas, such as bearings 80, 82, or at interior walls of the housing. The symmetrical design of the pump permits the radial load to be low, which results in a significant fluid film thickness on the order of 0.001 inch at bearings 80, 82. This avoids mechanical wear on the pump components, and minimizes fluid shear of the blood, both of which are obviously detrimental to the intended use of the pump. On the other hand, if the load is too low, the bearings can go into a well-known whirl mode, destroying the film thickness and the bearings. In this operating mode, instead of rotating around a fixed axis, the rotor rolls 360 degrees around the stator, wearing all surfaces of the rotor and stator.
The subject invention overcomes this problem by purposely and deliberately radially offsetting the centerline 100 of the motor stator relative to the centerline 102 of the drive housing portion 20 (FIG. 7). As a result of this offset, magnetic forces are higher at region 104, and lower at region 106, resulting in a known, controlled magnitude and direction of bearing loading. For example, preliminary tests of pump prototypes in accordance with the subject invention provide an offset on the order of 0.001-0.002 inch which results in magnetic forces of a few tenths of a pound at 104 and at 106. Because of this known force magnitude and direction, it is possible to calculate the running position of the rotor 60 (as represented by numeral 103, which is also representative of the centerline of the drive housing portion 20) and establish another centerline shift between the drive housing portion 20 and the rotor housing portion 18, such that the clearance between the impeller blades 64 and the housing wall is held more uniform around the circumference.
The axial motion of the pump rotor 60 must also be controlled to maintain a desired position of the rotor. The summation of pressure forces acting along the first and second fluid passages 70, 74, respectively, will tend to move the rotor relative to end wall 32. The magnetic attraction forces between the stator 34 and magnet assembly 38 are designed to be sufficient to overcome this tendency, even with slight variation of movement. FIG. 6 illustrates this operation. Axial motion is further limited during transients by the interaction of conical extension 110 on the rotor 60 with the housing cone 84 and inlet stop means which resemble stator blades 112. Should motions occur outside of normal limits, the rotor will contact stop means at controlled points of small diameter and consequent low rubbing velocity. Alternatively, stop means 112 could be replaced by reconfiguring the interior wall at a slightly different angle than that on rotor 60, such that any contact would be in a local, small diameter area adjacent to inlet 14.
FIG. 8 contains an alternative blood pump in accordance with the teachings of the subject invention. Like elements are referred to by like numerals with a primed (') suffix, while new elements are referenced by new numerals. Pump housing 12' is guidedly mounted to an external prime mover 120 by pilot diameter 122 and quick connect fasteners 124. The prime mover Could be an electric motor, or other suitable means of converting energy to rotary motion of the shaft 124. Fixedly mounted to the shaft 124 of the prime mover is a driver magnet assembly 126. This forms a magnetic coupling with driven magnet assembly 62' as will be understood by those skilled in the art. The driver and driven magnets rotate synchronously under the urging of the motor 120. The motor and magnet assembly functionally replace the stator 34 and coils 36 previously discussed as fixedly mounted in the housing 20 and together constitute the drive element of the drive means of this embodiment of the invention. As other details of construction of this embodiment are substantially identical to those already described except for the omission of the conical extension 110 and stop means 112, they will not be repeated here.
FIG. 9 illustrates an inverted embodiment of the invention, apparently different in configuration but generally working according to the same principles described above. Like numerals with a double primed suffix (") are used to identify like elements while new numerals refer to new elements.
The pump has a housing 10" having an inlet 14" and an outlet 16". The housing particularly comprises a drive housing portion 130 and a discharge housing portion 132. The housings are retained together by conventional fasteners 134 and sealed by O-rings 136. Installed Within the housing portion 130 is a motor stator 36" and associated Windings 34". Received in the housing portion is pump rotor 60", which comprises permanent magnet assembly 62", and impeller blade sets 64", 66". The primary blade set 64", though, is of axial flow geometry. It is further noted that the motor is now of conventional arrangement with the stator being of larger diameter and surrounding the magnet assembly 62". Axial extension 30" of the end wall 32" of housing forms radial bearing means 80", 83" to support the rotor.
As received in the housing 10", the pump rotor defines primary and secondary flow paths 70", 74", respectively. The primary impeller blades 64" are located in the first flow passage, and urge blood from inlet 14" to outlet 16". Stator blades 140 in the outlet housing slow the blood from and convert velocity into pressure energy. Secondary pump blades 66" urge blood from the inlet through passage 74" to the outlet. In a variation of this design, the secondary blades could be deleted and the wall separating the primary and secondary flow passages eliminated. In this case the primary impeller blades would urge flow through both the primary and "secondary" passage, and the bearing surfaces would be formed by the blade tips. Passage 74" is narrowed at each end of the pump rotor to form first and second fluid bearings 80", 82". As in the previous discussion of FIG. 7, centerline shift can be used to provide a stable load for these bearings. The net force resulting from the summation of pressures acting on the pump rotor is primarily reacted by the magnetic attraction of the stator and magnet assembly as diagrammed in FIG. 6. Transient axial motions, in turn, Can be limited by a plurality of struts 142 on the housing.
The invention has been described with reference to the preferred embodiments. Obviously, modification and alternations will occur to others upon the reading and understanding of the specification. It is our intention to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | A sealless centrifugal blood pump is provided in which a rotatable impeller is supported in a pump housing by fluid bearings during operation. Rotational movement of the impeller is accomplished with an inverted motor for magnetically driving of the impeller and maintenance of the axial running position of the impeller relative to the housing. In an alternative embodiment, the axis of the rotor housing is radially displaced relative to the axes of drive element of the motor and the motor housing. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 60/968,589 filed 29 Aug. 2007. The disclosure of this application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to deuterium-enriched celecoxib, pharmaceutical compositions containing the same, and methods of using the same.
BACKGROUND OF THE INVENTION
[0003] Celecoxib, shown below, is a well known nonsteroidal anti-inflammatory drug and inhibitor of cyclooxygenase 2.
[0000]
[0004] Since celecoxib is a known and useful pharmaceutical, it is desirable to discover novel derivatives thereof. Celecoxib is described in U.S. Pat. Nos. 5,466,823, 5,563,165, 5,760,068, and 5,972,986; the contents of which are incorporated herein by reference.
SUMMARY OF THE INVENTION
[0005] Accordingly, one object of the present invention is to provide deuterium-enriched celecoxib or a pharmaceutically acceptable salt thereof.
[0006] It is another object of the present invention to provide pharmaceutical compositions comprising a pharmaceutically acceptable carrier and a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0007] It is another object of the present invention to provide a method for treatment pain, tenderness, swelling and stiffness caused by osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis comprising administering to a host in need of such treatment a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0008] It is another object of the present invention to provide a novel deuterium-enriched alendronate sodium or a pharmaceutically acceptable salt thereof for use in therapy.
[0009] It is another object of the present invention to provide the use of a novel deuterium-enriched celecoxib or a pharmaceutically acceptable salt thereof for the manufacture of a medicament (e.g., for treatment pain, tenderness, swelling and stiffness caused by osteoarthritis, rheumatoid arthritis, and/or ankylosing spondylitis).
[0010] These and other objects, which will become apparent during the following detailed description, have been achieved by the inventor's discovery of the presently claimed deuterium-enriched celecoxib.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0011] Deuterium (D or 2 H) is a stable, non-radioactive isotope of hydrogen and has an atomic weight of 2.0144. Hydrogen naturally occurs as a mixture of the isotopes 1 H (hydrogen or protium), D ( 2 H or deuterium), and T ( 3 H or tritium). The natural abundance of deuterium is 0.015%. One of ordinary skill in the art recognizes that in all chemical compounds with a H atom, the H atom actually represents a mixture of H and D, with about 0.015% being D. Thus, compounds with a level of deuterium that has been enriched to be greater than its natural abundance of 0.015%, should be considered unnatural and, as a result, novel over their non-enriched counterparts.
[0012] All percentages given for the amount of deuterium present are mole percentages.
[0013] It can be quite difficult in the laboratory to achieve 100% deuteration at any one site of a lab scale amount of compound (e.g., milligram or greater). When 100% deuteration is recited or a deuterium atom is specifically shown in a structure, it is assumed that a small percentage of hydrogen may still be present. Deuterium-enriched can be achieved by either exchanging protons with deuterium or by synthesizing the molecule with enriched starting materials.
[0014] The present invention provides deuterium-enriched celecoxib. There are fourteen hydrogen atoms in the celecoxib portion of celecoxib as show by variables R 1 -R 14 in formula I, below or a pharmaceutically acceptable salt thereof.
[0000]
[0015] Hydrogen atoms R 1 and R 2 are easily exchangeable under physiological conditions and, if replaced by deuterium atoms, it is expected that they will readily exchange for protons after administration to a patient. The remaining hydrogen atoms are not readily exchangeable. Deuterium atom incorporation at these positions will require the use of deuterated starting materials or intermediates during the construction of celecoxib.
[0016] The present invention is based on increasing the amount of deuterium present in celecoxib above its natural abundance. This increasing is called enrichment or deuterium-enrichment. If not specifically noted, the percentage of enrichment refers to the percentage of deuterium present in the compound, mixture of compounds, or composition. Examples of the amount of enrichment include from about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16, 21, 25, 29, 33, 37, 42, 46, 50, 54, 58, 63, 67, 71, 75, 79, 84, 88, 92, 96, to about 100 mol %. Since there are 14 hydrogens in the celecoxib portion of celecoxib, replacement of a single hydrogen atom with deuterium would result in a molecule with about 7% deuterium enrichment. In order to achieve enrichment less than about 7%, but above the natural abundance, only partial deuteration of one site is required. Thus, less than about 7% enrichment would still refer to deuterium-enriched celecoxib.
[0017] With the natural abundance of deuterium being 0.015%, one would expect that for approximately every 6,667 molecules of celecoxib (1/0.00015=6,667), there is one naturally occurring molecule with one deuterium present. Since celecoxib has 14 positions, one would roughly expect that for approximately every 93,338 molecules of celecoxib (14×6,667), all 14 different, naturally occurring, mono-deuterated celecoxibs would be present. This approximation is a rough estimate as it doesn't take into account the different exchange rates of the hydrogen atoms on celecoxib. For naturally occurring molecules with more than one deuterium, the numbers become vastly larger. In view of this natural abundance, the present invention, in an embodiment, relates to an amount of an deuterium enriched compound, whereby the enrichment recited will be more than naturally occurring deuterated molecules.
[0018] In view of the natural abundance of deuterium-enriched celecoxib, the present invention also relates to isolated or purified deuterium-enriched celecoxib. The isolated or purified deuterium-enriched celecoxib is a group of molecules whose deuterium levels are above the naturally occurring levels (e.g., 7%). The isolated or purified deuterium-enriched celecoxib can be obtained by techniques known to those of skill in the art (e.g., see the syntheses described below).
[0019] The present invention also relates to compositions comprising deuterium-enriched celecoxib. The compositions require the presence of deuterium-enriched celecoxib which is greater than its natural abundance. For example, the compositions of the present invention can comprise (a) a μg of a deuterium-enriched celecoxib; (b) a mg of a deuterium-enriched celecoxib; and, (c) a gram of a deuterium-enriched celecoxib.
[0020] In an embodiment, the present invention provides an amount of a novel deuterium-enriched celecoxib.
[0021] Examples of amounts include, but are not limited to (a) at least 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, to 1 mole, (b) at least 0.1 moles, and (c) at least 1 mole of the compound. The present amounts also cover lab-scale (e.g., gram scale), kilo-lab scale (e.g., kilogram scale), and industrial or commercial scale (e.g., multi-kilogram or above scale) quantities as these will be more useful in the actual manufacture of a pharmaceutical. Industrial/commercial scale refers to the amount of product that would be produced in a batch that was designed for clinical testing, formulation, sale/distribution to the public, etc.
[0022] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0023] wherein R 1 -R 14 are independently selected from H and D; and the abundance of deuterium in R 1 -R 14 is at least 7%. The abundance can also be (a) at least 14%, (b) at least 21%, (c) at least 29%, (d) at least 36%, (e) at least 43%, (f) at least 50%, (g) at least 57%, (h) at least 64%, (i) at least 71%, (j) at least 79%, (k) at least 86%, (l) at least 93%, and (m) 100%.
[0024] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 is at least 50%. The abundance can also be (a) at least 100%.
[0025] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0026] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 8 -R 11 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0027] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 12 -R 14 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0028] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 3 -R 6 is at least 17%. The abundance can also be (a) at least 33%, (b) at least 50%, (c) at least 67%, (d) at least 83%, and (e) 100%.
[0029] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 8 -R 11 is at least 17%. The abundance can also be (a) at least 33%, (b) at least 50%, (c) at least 67%, (d) at least 83%, and (e) 100%.
[0030] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 12 -R 14 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0031] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 and R 8 -R 11 is at least 13%. The abundance can also be (a) at least 25%, (b) at least 38%, (c) at least 50%, (d) at least 63%, (e) at least 75%, (f) at least 88%, and (g) 100%.
[0032] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 and R 12 -R 14 is at least 14%. The abundance can also be (a) at least 29%, (b) at least 43%, (c) at least 57%, (d) at least 71%, (e) at least 86%, and (f) 100%.
[0033] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 8 -R 11 and R 12 -R 14 is at least 14%. The abundance can also be (a) at least 29%, (b) at least 43%, (c) at least 57%, (d) at least 71%, (e) at least 86%, and (f) 100%.
[0034] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 3 -R 6 , and R 8 -R 11 is at least 10%. The abundance can also be (a) at least 20%, (b) at least 30%, (c) at least 40%, (d) at least 50%, (e) at least 60%, (f) at least 70%, (g) at least 80%, (h) at least 90%, and (i) 100%.
[0035] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 3 -R 6 , and R 12 -R 14 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0036] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 8 -R 11 , and R 12 -R 14 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0037] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 , R 8 -R 11 , and R 12 -R 14 is at least 9%. The abundance can also be (a) at least 18%, (b) at least 27%, (c) at least 36%, (d) at least 45%, (e) at least 56%, (f) at least 64%, (g) at least 73%, (h) at least 82%, (i) at least 91%, and (j) 100%.
[0038] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0039] wherein R 1 -R 14 are independently selected from H and D; and the abundance of deuterium in R 1 -R 14 is at least 7%. The abundance can also be (a) at least 14%, (b) at least 21%, (c) at least 29%, (d) at least 36%, (e) at least 43%, (f) at least 50%, (g) at least 57%, (h) at least 64%, (i) at least 71%, (j) at least 79%, (k) at least 86%, (l) at least 93%, and (m) 100%.
[0040] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0041] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 14 is at least 8%. The abundance can also be (a) at least 17%, (b) at least 25%, (c) at least 33%, (d) at least 42%, (e) at least 50%, (f) at least 58%, (g) at least 67%, (h) at least 75%, (i) at least 83%, (j) at least 92%, and (k) 100%.
[0042] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 8 -R 11 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0043] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 12 -R 14 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0044] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 3 -R 6 is at least 17%. The abundance can also be (a) at least 33%, (b) at least 50%, (c) at least 67%, (d) at least 83%, and (e) 100%.
[0045] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 8 -R 11 is at least 17%. The abundance can also be (a) at least 33%, (b) at least 50%, (c) at least 67%, (d) at least 83%, and (e) 100%.
[0046] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 12 -R 14 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0047] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 and R 8 -R 11 is at least 13%. The abundance can also be (a) at least 25%, (b) at least 38%, (c) at least 50%, (d) at least 63%, (e) at least 75%, (f) at least 88%, and (g) 100%.
[0048] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 and R 12 -R 14 is at least 14%. The abundance can also be (a) at least 29%, (b) at least 43%, (c) at least 57%, (d) at least 71%, (e) at least 86%, and (f) 100%.
[0049] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 8 -R 11 and R 12 -R 14 is at least 14%. The abundance can also be (a) at least 29%, (b) at least 43%, (c) at least 57%, (d) at least 71%, (e) at least 86%, and (f) 100%.
[0050] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 3 -R 6 , and R 8 -R 11 is at least 10%. The abundance can also be (a) at least 20%, (b) at least 30%, (c) at least 40%, (d) at least 50%, (e) at least 60%, (f) at least 70%, (g) at least 80%, (h) at least 90%, and (i) 100%.
[0051] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 3 -R 6 , and R 12 -R 14 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0052] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 8 -R 11 , and R 12 -R 14 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0053] In another embodiment, the present invention provides an isolated novel deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 , R 8 -R 11 , and R 12 -R 14 is at least 9%. The abundance can also be (a) at least 18%, (b) at least 27%, (c) at least 36%, (d) at least 45%, (e) at least 56%, (f) at least 64%, (g) at least 73%, (h) at least 82%, (i) at least 91%, and (j) 100%.
[0054] In another embodiment, the present invention provides novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0055] wherein R 1 -R 14 are independently selected from H and D; and the abundance of deuterium in R 1 -R 14 is at least 7%. The abundance can also be (a) at least 14%, (b) at least 21%, (c) at least 29%, (d) at least 36%, (e) at least 43%, (f) at least 50%, (g) at least 57%, (h) at least 64%, (i) at least 71%, (j) at least 79%, (k) at least 86%, (l) at least 93%, and (m) 100%.
[0056] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 is at least 50%. The abundance can also be (a) at least 100%.
[0057] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0058] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 8 -R 11 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0059] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 12 -R 14 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0060] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 3 -R 6 is at least 17%. The abundance can also be (a) at least 33%, (b) at least 50%, (c) at least 67%, (d) at least 83%, and (e) 100%.
[0061] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 8 -R 11 is at least 17%. The abundance can also be (a) at least 33%, (b) at least 50%, (c) at least 67%, (d) at least 83%, and (e) 100%.
[0062] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 and R 12 -R 14 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0063] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 and R 8 -R 11 is at least 13%. The abundance can also be (a) at least 25%, (b) at least 38%, (c) at least 50%, (d) at least 63%, (e) at least 75%, (f) at least 88%, and (g) 100%.
[0064] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 and R 12 -R 14 is at least 14%. The abundance can also be (a) at least 29%, (b) at least 43%, (c) at least 57%, (d) at least 71%, (e) at least 86%, and (f) 100%.
[0065] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 8 -R 11 and R 12 -R 14 is at least 14%. The abundance can also be (a) at least 29%, (b) at least 43%, (c) at least 57%, (d) at least 71%, (e) at least 86%, and (f) 100%.
[0066] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 3 -R 6 , and R 8 -R 11 is at least 10%. The abundance can also be (a) at least 20%, (b) at least 30%, (c) at least 40%, (d) at least 50%, (e) at least 60%, (f) at least 70%, (g) at least 80%, (h) at least 90%, and (i) 100%.
[0067] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 3 -R 6 , and R 12 -R 14 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0068] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 , R 8 -R 11 , and R 12 -R 14 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0069] In another embodiment, the present invention provides a novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 6 , R 8 -R 11 , and R 12 -R 14 is at least 9%. The abundance can also be (a) at least 18%, (b) at least 27%, (c) at least 36%, (d) at least 45%, (e) at least 56%, (f) at least 64%, (g) at least 73%, (h) at least 82%, (i) at least 91%, and (j) 100%.
[0070] In another embodiment, the present invention provides novel pharmaceutical compositions, comprising: a pharmaceutically acceptable carrier and a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0071] In another embodiment, the present invention provides a novel method for treating pain, tenderness, swelling and stiffniess caused by osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis comprising: administering to a patient in need thereof a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0072] In another embodiment, the present invention provides an amount of a deuterium-enriched compound of the present invention as described above for use in therapy.
[0073] In another embodiment, the present invention provides the use of an amount of a deuterium-enriched compound of the present invention for the manufacture of a medicament for the treatment of pain, tenderness, swelling and stiffniess caused by osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis.
[0074] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. This invention encompasses all combinations of preferred aspects of the invention noted herein. It is understood that any and all embodiments of the present invention may be taken in conjunction with any other embodiment or embodiments to describe additional more preferred embodiments. It is also to be understood that each individual element of the preferred embodiments is intended to be taken individually as its own independent preferred embodiment. Furthermore, any element of an embodiment is meant to be combined with any and all other elements from any embodiment to describe an additional embodiment.
Definitions
[0075] The examples provided in the definitions present in this application are non-inclusive unless otherwise stated. They include but are not limited to the recited examples.
[0076] The compounds of the present invention may have asymmetric centers. Compounds of the present invention containing an asymmetrically substituted atom may be isolated in optically active or racemic forms. It is well known in the art how to prepare optically active forms, such as by resolution of racemic forms or by synthesis from optically active starting materials. All processes used to prepare compounds of the present invention and intermediates made therein are considered to be part of the present invention. All tautomers of shown or described compounds are also considered to be part of the present invention.
[0077] “Host” preferably refers to a human. It also includes other mammals including the equine, porcine, bovine, feline, and canine families.
[0078] “Treating” or “treatment” covers the treatment of a disease-state in a mammal, and includes: (a) preventing the disease-state from occurring in a mammal, in particular, when such mammal is predisposed to the disease-state but has not yet been diagnosed as having it; (b) inhibiting the disease-state, e.g., arresting it development; and/or (c) relieving the disease-state, e.g., causing regression of the disease state until a desired endpoint is reached. Treating also includes the amelioration of a symptom of a disease (e.g., lessen the pain or discomfort), wherein such amelioration may or may not be directly affecting the disease (e.g., cause, transmission, expression, etc.).
[0079] “Therapeutically effective amount” includes an amount of a compound of the present invention that is effective when administered alone or in combination to treat the desired condition or disorder. “Therapeutically effective amount” includes an amount of the combination of compounds claimed that is effective to treat the desired condition or disorder. The combination of compounds is preferably a synergistic combination. Synergy, as described, for example, by Chou and Talalay, Adv. Enzyme Regul. 1984, 22:27-55, occurs when the effect of the compounds when administered in combination is greater than the additive effect of the compounds when administered alone as a single agent. In general, a synergistic effect is most clearly demonstrated at sub-optimal concentrations of the compounds. Synergy can be in terms of lower cytotoxicity, increased antiviral effect, or some other beneficial effect of the combination compared with the individual components.
[0080] “Pharmaceutically acceptable salts” refer to derivatives of the disclosed compounds wherein the parent compound is modified by making acid or base salts thereof. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of the basic residues. The pharmaceutically acceptable salts include the conventional quaternary ammonium salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include, but are not limited to, those derived from inorganic and organic acids selected from 1,2-ethanedisulfonic, 2-acetoxybenzoic, 2-hydroxyethanesulfonic, acetic, ascorbic, benzenesulfonic, benzoic, bicarbonic, carbonic, citric, edetic, ethane disulfonic, ethane sulfonic, fumaric, glucoheptonic, gluconic, glutamic, glycolic, glycollyarsanilic, hexylresorcinic, hydrabamic, hydrobromic, hydrochloric, hydroiodide, hydroxymaleic, hydroxynaphthoic, isethionic, lactic, lactobionic, lauryl sulfonic, maleic, malic, mandelic, methanesulfonic, napsylic, nitric, oxalic, pamoic, pantothenic, phenylacetic, phosphoric, polygalacturonic, propionic, salicyclic, stearic, subacetic, succinic, sulfamic, sulfanilic, sulfuric, tannic, tartaric, and toluenesulfonic.
Synthesis
[0081] Scheme 1 shows an example of how to prepare celecoxib (see for example U.S. Pat. No. 5,466,823 and Penning, et al., J. Med. Chem. 1997, 40, 1347-1365).
[0000]
[0082] Synthesis of deuterated celecoxibs from deuterated starting materials and intermediates (Scheme 2). Scheme 2 shows how various deuterated starting materials and intermediates from Scheme 1 can be accessed and used to make deuterated celecoxib analogs. A person skilled in the art of organic synthesis will recognize that these reactions and these materials may be used in various combinations to access a variety of deuterated celecoxibs.
[0083] The sulfonamide 1 can be prepared by a variety of routes starting ultimately with aniline, for example as shown in equation (1) ( Pol. J. Chem. 1983, 57, 451-454). Diazotization of 1 followed by reduction to the hydrazine 2 is also well-known (e.g., J. Med. Chem., 2005, 48, 2121-2125). Use of 2 in Scheme 1 would provide celecoxib with R 3 -R 6 =D. Friedel-Crafts acylation of perdeuteriotoluene will provide 3 and thus 4 as shown in equation (2), ultimately providing access to celecoxib with R 8 -R 14 =D. A combination of the deuterated reagents in equations (1) and (2) would provide celecoxib with R 3 -R 6 , R 8 -R 14 =D. Equation (3) shows how R 7 could be replaced by deuterium. Again, various combinations of these reactions and intermediates would produce celecoxib with a variety of different deuteration patterns.
[0000]
[0084] Other features of the invention will become apparent in the course of the following descriptions of exemplary embodiments that are given for illustration of the invention and are not intended to be limiting thereof.
EXAMPLES
[0085] Table 1 provides compounds that are representative examples of the present invention. When one of R 1 -R 14 is present, it is selected from H or D.
[0000]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
[0086] Table 2 provides compounds that are representative examples of the present invention. Where H is shown, it represents naturally abundant hydrogen.
[0000]
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
[0087] 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 that as specifically described herein. | The present application describes deuterium-enriched celecoxib, pharmaceutically acceptable salt forms thereof, and methods of treating using the same. | 2 |
The Government of the United States of America has rights in this invention pursuant to Contract Agreement No. 26-6578 entered into with Sandia National Laboratories on behalf of the U.S. Department of Energy.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to secondary batteries employing microporous separators and having as the electrolyte an aqueous metal bromide solution containing a complexing constituent capable of forming a water immiscible complex with cathodic bromine.
2. Prior Art
As is well known in the art, electrochemical cells have been proposed which have one electrode with a high positive oxidizing potential and another electrode with a strong negative or reducing potential. Typical of such cells is the metal halogen cell in which the anode material typically is zinc or cadmium and the cathodic halogen typically is bromine. Among the advantages of such metal halogen cells is their extremely high theoretical energy density. For example, a zinc bromine cell has a theoretical energy density of 200 Wh/lb., i.e., watt hours per pound, and an electric potential of about 1.8 volts per cell.
Electrochemical cells of the foregoing type are known to suffer from a number of disadvantages. Most of these disadvantages are associated with side reactions which may occur in such cells. For example, during the charging process free bromine is generated in the cell. This free bromine is available for electrochemical reaction with the zinc anode thereby resulting in auto discharge of the cell.
In U.S. Pat. No. 4,105,829 there is disclosed a metal halogen cell which employs a circulating electrolyte system containing complexing agent to effectively remove cathodic halogen from the electrolyte during charging of the cell. Basically, the complexing constituent or complexing agent is one which in the presence of halogen forms a water immiscible halogen complex. This complex is separated and stored external the cell during charging and is returned to the cell during discharge.
Another typical feature of the metal halogen cell disclosed in the aforementioned patent is that a microporous separator is employed. Among other things, the microporous separator serves to prevent contact of the metal anode with the counterelectrode in the cell, and it reduces contact of the metal anode with cathodic halogen during charging of the cell.
Despite the significant improvement that is achieved with the aqueous zinc bromine battery disclosed in the aforementioned patent, coulombic inefficiencies still result in operating such cells since the amount of energy recovered from the cell is less than that which is put in during charging of the cell.
SUMMARY OF THE INVENTION
It has now been discovered that the coulombic efficiency of such cells can be increased if an additive which is capable of decreasing the wettability of the microporous membrane separator in the cell by the water immiscible halogen complex, is added to the electrolyte. Thus, in one embodiment of the present invention, there is provided an electrochemical cell having a metal bromine couple. The cell includes an electrode structure on which to deposit the metal of the couple and a counterelectrode at which to generate bromine. A microporous membrane separates the electrode and counterelectrode. Importantly, the aqueous electrolyte comprises an aqueous metal bromide solution containing a water soluble bromine complexing agent capable of forming a water immiscible complex with bromine and an additive capable of decreasing the wettability of the microporous separators employed in such cells by such water immiscible bromine complexes.
BRIEF DESCRIPTION OF THE DRAWINGS
The sole FIGURE is schematic diagram of a typical circulating zinc bromine electrochemical cell which can benefit from the use of the additive of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In the description which follows, for convenience, the metal of the metal halogen couple will be referred to as the anode and the halogen as the cathode. It will be appreciated, however, that the metal halogen cell is a secondary cell and consequently the halogen acts as a cathode on discharge and as an anode on charging. Similarly, the metal of the couple acts as an anode on discharge of the cell and as a cathode on its charging.
Referring now to the FIGURE, a schematic diagram of a typical circulating bipolar metal bromine electrochemical cell 10 is shown. The zinc bromine electrochemical cell comprises two electrolytes (an anolyte and a catholyte) which are circulated through separate compartments 8 and 9, respectively. In cell 10, the anolyte is stored in reservoir 11 and circulated via pump 12 through compartment 8 and loop 13 which is generally referred to as the anolyte loop. A catholyte, which generally is stored in reservoir 14 is circulated by pump 15 through compartment 9 and loop 16 and it is generally referred to as the catholyte loop.
A microporous separator 18 delineates and defines the boundary between the anode and cathode compartments 8 and 9, respectively. Separator 18 is a membrane which prevents or hinders movements of anions, e.g., bromide and polybromide ions including tribromide, pentabromide and heptabromide ions, from the cathode compartment 9 to the anode compartment 8. Such membranes are well known and are commercially available. Typical membranes include separator materials sold under the name Daramic by W. R. Grace and Co., Baltimore, Md, Submicro, sold by Evans Products Co., New York, N.Y., and Hipore, sold by Asahi Chemicals, Tokyo, Japan, each of which comprise a porous silica phase imbedded in a polyolefin binder.
In a bipolar cell design, the electrode structure 19 for the deposition of the metal of the couple, for example, zinc, and the electrode structure 17 for the generation of bromine are on opposite sides of the same electrode structure.
The electrolyte of the present invention is an aqueous solution of a metal bromide, the metal of the metal bromide being the same metal as that of the anode. Indeed, that metal is selected from cadmium and zinc and for convenience reference hereinafter will be made only to zinc. In general, the electrolyte will contain about 1 to 6 and preferably about 3 moles of zinc bromide. The electrolyte of the present invention also includes a complexing constituent which is capable of forming a water immiscible complex in the presence of elemental bromine.
Suitable complexing constituents for use in the electrolyte of the present invention are set forth in U.S. Pat. No. 4,105,829 which is incorporated herein by reference. Among the preferred complexing constituents in the practice of the present invention are N-methyl, N-ethyl morphollium bromide, N-methyl, N-ethyl pyrollidinium bromide and N-methyl, N-ethyl piperidinium bromide and mixtures thereof.
It is a significant feature of the present invention that the electrolyte contain an additive which is capable of decreasing the wettability of the microporous separator by the water immiscible bromine complex that forms during charging of the cell. In general, the additive will be a surfactant; however, not all surfactants will produce the desired result. Screening of suitable additives is conducted very simply by vertically suspending a separator in a clear vessel which contains aqueous electrolyte including the test additive and a water immiscible bromine complex of the type to be formed in the cell under conditions of use. If the test additive inhibits the wetting of the separator, the bromine complex will not wick-up the separator but will remain at substantially the same level in the vessel. Among suitable surfactants that are capable of decreasing the wettability of microporous battery separators by water immiscible bromine complexes are sodium dodecylsulfate and sodium dodecylbenzene sulfonate.
Also, it has been found that use of such additives, even in relatively small amounts, increases the coulombic efficiency of cells employing such additives whereas when no such additive is used and the separator is wet by the bromine complex the coulombic inefficiency of the cell increases. In general, the amount of surfactant employed should be sufficient to provide a measurable increase in the coulombic efficiency of the cell, and preferably will be in the range of about 0.01 wt. % to about 0.3 wt. %.
Referring again to the FIGURE, in operation anolyte and catholyte are circulated through the cell 10 by means of pump 12 or 15, respectively. At least the catholyte has the composition described in accordance with the present invention; however, for convenience, both the anolyte and catholyte have the same composition prior to charging the cell. An electrode potential is applied to the cell resulting in deposition of zinc shown as layer 20 on electrode 19. Bromine also is generated. The bromine which is generated at the chemically inert electrode structure 17 reacts with complexing agent in the electrolyte to form a substantially water immiscible complex 14a. Since the bromine rich complex 14a is heavier than water, it tends to settle on the bottom of tank 14 and is therefore not recirculated, at least in any substantial amount through the cell during charging. Indeed, the baffle 21 in the holding tank 14 helps with the separation of the bromine containing aqueous soluble complex. Consequently, substantially only an aqueous phase is recirculated through the cell during the charging period. On discharging, however, the complex is flowed back to the cathode by first emulsifying and dispersing it in the aqueous phase. This can be accomplished by mixing means (not shown). For example, a high shear or ultrasonic mixing device can be incorporated within the gravity separated tank. In such case, activation of the mixing mechanism will be initiated prior to discharge of the cell. Optionally pipe means 22 as shown can be used for drawing substantially the water immiscible complex 14a from the bottom of the separator tank. In any event, the bromine phase will be distributed as an emulsion in the aqueous phase and recirculated through the electrolyte chamber during cell discharge.
To illustrate the improved coulombic efficiency obtained in accordance with the present invention, reference is made to the following example.
EXAMPLE
An eight-cell bipolar battery was assembled with 1200 cm 2 bipolar electrodes and microporous separators comprising a porous silica phase embedded in a polyolefin binder and sold under the trademark "Daramic". To the battery, 81 of electrolyte was added, and the battery system was placed on a cycle testing routine. The routine consisted of a 3-hr, 24 A charging and a 24 A discharging to an 8 V (1 V/cell) cutoff. The ratio of discharge time to charge time was a measure of coulombic efficiency. This test procedure was carried out with both electrolytes A and B, the composition of which are given in Table I below.
TABLE I______________________________________Electrolyte Composition______________________________________A 3 M ZnBr.sub.2 0.5 M N--methyl, N--ethyl morpholinium bromide 0.5 M N--methyl, N--ethyl pyrollidinium bromideB 2 M ZnBr.sub.2 1 M ZnCl.sub.2 0.5 M N--methyl, N--ethyl morpholinium bromide 0.5 M N--methyl, N--ethyl pyrollidinium bromide______________________________________
Also, after establishing the coulombic efficiency of the battery with each electrolyte, sodium dodecyl sulfate was added to the electrolyte (anolyte and catholyte) when the battery was discharged. Sodium dodecyl sulfate was selected since its presence decreased the wettability of the microporous separator by the bromine complex generated during charging of the cell. The electrolyte was circulated for 2 to 16 hrs to evenly distribute the sodium dodecyl sulfate. Then the charge/discharge regimen was repeated. The results are set forth in Table II below.
TABLE II______________________________________ Sodium Dodecyl CoulombicRun Electrolyte Sulfate, wt % Efficiency, %______________________________________1 A None 712 A .01 803 A .03 81.54 A .1 845 B None 806 B .1 90______________________________________ | In one embodiment of the present invention, there is provided an electrochemical cell having a metal bromine couple. The cell includes an electrode structure on which to deposit the metal of the couple and a counterelectrode at which to generate bromine. A microporous membrane separates the electrode and counterelectrode. Importantly, the aqueous electrolyte comprises an aqueous metal bromide solution containing a water soluble bromine complexing agent capable of forming a water immiscible complex with bromine and an additive capable of decreasing the wettability of the microporous separators employed in such cells by such water immiscible bromine complexes. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is the U.S. national phase, under 35 U.S.C. 371, of PCT/EP2007/063398, filed Dec. 6, 2007; published as WO 2007/077730 A2 and A3 on Jul. 3, 2008 and claiming priority to DE 10 2006 061 316.3 filed Dec. 22, 2006, the disclosures of which are specifically incorporated herein by reference.
FIELD OF THE INVENTION
The present invention is directed to devices comprising a plurality of storage compartments which are arranged spaced from one another. The storage compartments are spaced from each other and are adapted to store either a printing forme that has been removed from a forme cylinder or a printing forme which is to be loaded onto the forme cylinder. At least one positioning device is associated with the plurality of storage compartments.
BACKGROUND OF THE INVENTION
A device which is usable for storing a blanket to be supplied to a cylinder of a printing press, and a method for supplying blankets to a cylinder of a printing press are known from WO 2004/085157 A1. At least two storage planes, which are arranged spaced from one another, are provided. A printing forme, which is to be mounted on a forme cylinder of a rotary printing press, can be stored on each storage plane. At least one conveyor mechanism, for use in conveying the respective printing forme up to or away from the forme cylinder, is provided. The storage planes are spaced substantially perpendicular to the direction of conveyance of the printing formes to be supplied to or carried away from the forme cylinder. With the device of WO 2004/085157 A1, printing formes to be supplied to a forme cylinder of a rotary printing press are conveyed by virtue of gravitational force from a first storage plane to a second storage plane. Such a conveyance is accomplished once a retaining assembly, which hold the printing forme in its first storage plane, have been released from the relevant printing forme. In the severe conditions which often exist in a rotary printing press, this release process can cause problems.
SUMMARY OF THE INVENTION
The object of the present invention is to provide devices having a plurality of storage compartments that are arranged spaced from one another. The reliability in supplying a printing forme to be supplied to the forme cylinder or in removing a printing forme to be removed from the forme cylinder is improved through the use of the storage device in accordance with the present invention.
The object in accordance with the present invention is attained with the provision of a storage device that is provided with a plurality of storage compartments which are arranged spaced at a distance from each other. These storage compartments are usable to receive a printing forme that has been removed from a forme cylinder, or to store a printing forme that will be loaded on a forme cylinder. A positioning device is usable with the storage device to selectively locate an opening area of a selected one of the at least two storage compartments facing the forme cylinder. Each opening area of its associate storage chamber can be placed against the forme cylinder at the appropriate time. At least one conveyor device, which is provided with a printing forme engaging carrier is provided in the used printing forme receiving compartment. An advancing mechanism, with a slider element, is in the new printing forme delivery compartment. A positioning assembly is usable to adjust the positions of the carrier and slider relative to its compartment.
The benefits to be achieved in accordance with the present invention consist, in particular, that a printing forme can be reliably supplied to, or can be reliably removed from a forme cylinder of a rotary printing press using the described devices.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention is represented in the accompanying set of drawings and will be described in greater detail in what follows. The drawings show:
FIG. 1 to 10 various individual steps of a plate loading process;
FIG. 11 to 15 various individual steps of a plate removal process;
FIGS. 16 and 17 perspective views of a device having a plurality of storage compartments, both one above another and taken in the axial direction of the forme cylinder;
FIG. 18 to 24 schematic side elevation views of various arrangements of the device in accordance with the present invention and having a plurality of storage compartments, and showing the device in cooperation with various printing unit variations.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 10 each schematically show the same section of a printing couple of a rotary printing press, and together illustrate the sequence of steps which occur during plate removal, and specifically which occur during the removal of printing formes from a forme cylinder of this printing couple. FIGS. 11 to 15 each show the same section of the printing couple of the rotary printing press shown in FIGS. 1 to 10 , and illustrate the sequence of steps which occur during plate loading, and specifically which occur during the supplying of printing formes to the forme cylinder of this printing couple. The printing formes to be supplied and/or removed are preferably flexible in structure in a direction along their length, which is a direction that is generally perpendicular to the axis of rotation of the forme cylinder. Each of the printing formes is typically embodied as being generally plate-shaped and provided with a substantially rectangular surface. This substantially rectangular surface typically measures between 400 mm and 1300 mm in length, for example, and measures between 280 mm and 1500 mm in width, for example. Preferred measurements for printing formes used in newspaper printing, for example, range from 360 mm to 800 mm in length, for example, and from 250 mm to 430 mm in width, for example.
In each of FIGS. 1 to 15 , at least parts of a forme cylinder 01 , an ink forme roller 02 and other rollers 03 , 04 , 06 of an inking unit 07 are represented. In the configuration which is shown in FIGS. 1 to 15 , two printing formes 08 can be arranged, one in front of another, on the circumference of the forme cylinder 01 . Each printing forme 08 has a preferably acutely angled suspension leg 09 at its leading end and a suspension leg 11 which is angled substantially at a right angle or an obtuse angle, for example, at its trailing end, with the respective suspension legs 09 ; 11 each measuring a few millimeters, such as, for example, measuring between 3 mm and 15 mm, in length. A material thickness of the suspension legs 09 ; 11 , which may be made, for example, of a metallic material, ranges from 0.15 mm to 0.5 mm and is, for example, 0.3 mm. The respective angling of the suspension legs 09 ; 11 is directed toward the rear or under side of the respective printing forme 08 . In other words, the angling is directed toward the printing forme surface which faces away from its print image side 12 , and which is located between its leading and trailing ends. The respective printing forme 08 , when each is mounted on the circumferential surface of the forme cylinder 01 , rests with that underside surface on the circumferential surface of the forme cylinder 01 . The forme cylinder 01 has at least one axially parallel and extending groove 13 on its periphery, in the opening 14 of which groove 13 at least one of the suspension legs 09 ; 11 of the respective printing forme 08 is suspended. The opening 14 of the respective groove 13 is preferably slit-shaped in configuration and has a slit width of less than 5 mm, for example, and preferably has a slit width ranging from 1 mm to 3 mm. In FIGS. 1 to 15 , only one of the two grooves 13 , which are typically arranged offset 180° from one another on the circumference of the forme cylinder 01 , is shown. Additionally, this groove 13 is represented only schematically relative to the printing forme 08 which is to be removed, and is not shown true to position. In the selected section of a printing couple of the rotary printing press shown in FIGS. 1 to 15 , the intention is merely to indicate the general presence of these printing forme end receiving grooves 13 . The circumferential position of the respective groove 13 that is necessary for the plate removal and/or loading sequence is adjusted by a rotational movement of the forme cylinder 01 in the appropriate direction.
Near the periphery of the forme cylinder 01 , there is provided at least one contact pressure element 16 , which may be, for example, a roller element 16 , and preferably may be a roller strip 16 . Actuation of a positioning assembly 17 causes the contact pressure element 16 to execute a radial movement relative to the forme cylinder 01 , thereby allowing it to be engaged against, or to be disengaged from the circumferential surface of the forme cylinder 01 . When the contact pressure element 16 is engaged in this manner, a printing forme 08 will be pressed against the circumferential surface of the forme cylinder 01 , for example. This is indicated in FIGS. 1 to 15 by the use of dashed lines representing the contact pressure element 16 . In FIGS. 1 to 15 , a device 18 for use in supplying a printing forme 08 true to register for loading is also indicated. This register device 18 , when it is actuated, positions at least one stop, which is not specifically shown, in an infeed plane for the printing forme 08 to be loaded. The printing forme 08 to be loaded strikes laterally against the at least one stop during its infeed movement. The printing forme 08 to be loaded is thus guided laterally. Preferably, a guide element 19 , such as for example, a roller guide element 19 , which is actuable via a positioning assembly 21 , is also provided near the periphery of the forme cylinder 01 . When this guide element 19 is actuated, it serves to guide preferably the trailing end of a printing forme 08 that is to be removed from the forme cylinder 01 .
At least one first storage compartment 22 , in which at least one printing forme 08 that has been removed can be stored, is provided. This first storage compartment 22 is preferably oriented in a preferably substantially tangential alignment relative to the circumference of the forme cylinder 01 . In the preferred embodiment of the present invention, which is represented in the drawings, a plurality of removed printing formes 08 , such as, for example two such printing formes, can preferably be stored one above the other in this first storage compartment 22 . A first printing forme 08 to be removed is placed on a first support surface 26 that belongs to this first storage compartment 22 . At a preferably invariable distance “a” from this first support surface 26 of the first storage compartment 22 , with this distance “a” remaining constant over its respective length, for example, at least one second storage compartment 23 is provided. A printing forme 08 , that is to be loaded on the forme cylinder 01 , can be stored in this second storage compartment 23 . The second storage compartment 23 preferably has a second support surface 27 , on which second support surface the printing forme 08 , that is to be loaded onto the forme cylinder 01 , is placed. The printing forme 08 to be loaded rests, on at least a portion of its length or surface, on this second support surface 27 until it is loaded onto the forme cylinder 01 .
A third storage compartment 24 , in which another printing forme 08 , that is to be loaded onto the forme cylinder 01 , can be stored, is preferably provided at another, such as, for example, a constant, distance “b” from the second support surface 27 belonging to the second storage compartment 23 . This additional printing forme 08 to be loaded is preferably placed or, at least can be placed on a third support surface 28 belonging to this third storage compartment 24 . The respective distance “a”; “b” between the respective support surfaces 26 ; 27 ; 28 of the relevant storage compartments 22 ; 23 ; 24 , preferably remains constant over the length of the relevant storage compartment 22 ; 23 ; 24 . Each such distance “a”; “b” exists preferably perpendicular to a direction of conveyance of the printing formes 08 to be conveyed toward or away from the forme cylinder 01 . The respective direction of conveyance of each printing forme 08 is oriented substantially parallel to a longitudinal extension of the respective support surface 26 ; 27 ; 28 , which respective support surface 26 ; 27 ; 28 runs parallel to the length of the respective printing forme 08 . The respective storage compartments 22 ; 23 ; 24 are all arranged with their respective support surfaces 26 ; 27 ; 28 substantially parallel to one another, for example. The respective support surface 26 ; 27 ; 28 can each be embodied as at least one holding member for holding the respective printing forme 08 to be stored, or as at least one guide rail which engages laterally on the respective printing forme 08 to be stored, for example. Each respective printing forme 08 to be stored preferably rests, or at least can be placed, with only its two edges that each respectively extend parallel to the length of the respective printing forme 08 , rather than over its entire surface, on suitable, spaced guide rails, which are arranged opposite one another in pairs, as may be seen by referring to FIG. 16 and FIG. 17 .
Each of these storage compartments 22 ; 23 ; 24 , which are all used to each store at least one printing forme 08 , accordingly has a boundary that separates it from its respective surrounding area. Each of the storage compartments 22 ; 23 ; 24 preferably has a support surface 26 ; 27 ; 28 on which at least one printing forme 08 , which is to be stored in the respective storage compartment 22 ; 23 ; 24 , can be placed. In each case, the respective boundary of the relevant storage compartment 22 ; 23 ; 24 is provided, for example, by the relevant support surface 26 ; 27 ; 28 for the respective printing forme 08 to be stored there. The dimensions of each relevant storage compartment 22 ; 23 ; 24 are also each defined by the relevant support surface 26 ; 27 ; 28 . The dimensions of each respective storage compartment 22 ; 23 ; 24 , in terms of its length and width, are preferably defined such that each relevant storage compartment 22 ; 23 ; 24 encompasses the flat, rectangular surface of a plate-shaped printing forme 08 to be stored therein. The height of each respective storage compartment 22 ; 23 ; 24 is preferably defined such that a printing forme 08 , to be stored in this storage compartment 22 ; 23 ; 24 , and including its respective angled suspension legs 09 ; 11 , can be fully placed therein, without projecting into another one of the adjacent storage compartments 22 ; 23 ; 24 , which are arranged, for example, in a stack, one above the other. The relevant storage compartments 22 ; 23 ; 24 are slightly longer and slightly wider, such as preferably by only a few millimeters, and for example preferably longer and wider by between 1 mm and 10 mm, than are the respective printing forme or formes 08 which are to be stored in this relevant storage compartment 22 ; 23 ; 24 . The same criteria applies to the height of each respective storage compartment 22 ; 23 ; 24 . The storage compartments 22 ; 23 ; 24 , with their respective support surfaces 26 ; 27 ; 28 , can preferably be provided in a magazine for use in storing printing formes 08 , for example. That magazine preferably has a housing which encompasses the respective storage compartments 22 ; 23 ; 24 together, for example. These storage compartments 22 ; 23 ; 24 , with their respective associated support surfaces 26 ; 27 ; 28 , if applicable, each form a component part of the relevant overall magazine.
The support surfaces 26 ; 27 ; 28 of preferably all of the respective storage compartments 22 ; 23 ; 24 are especially rigidly, but each separably connected, for example, to a cross member 29 , and preferably to the same cross member 29 , which extends axially parallel to the forme cylinder 01 . FIG. 16 and FIG. 17 each show a perspective schematic representation of an assembly comprising a plurality of these first, second and third storage compartments 22 ; 23 ; 24 which are arranged side by side in the axial direction of the forme cylinder 01 . In the example which is schematically shown in FIG. 16 , in each case, six printing formes 08 are stored, or at least can be stored, and are arranged side by side in the axial direction of the forme cylinder 01 . In the example which is schematically shown in FIG. 17 , rather than the six printing formes 08 , in each case three double-width printing formes 08 are stored, or at least can be stored, again, oriented side by side in the axial direction of the forme cylinder 01 . The double-width printing formes 08 are also called panoramic printing formes 08 . To allow such panoramic or double-width printing formes 08 to be stored in each of the respective storage compartments 22 ; 23 ; 24 , three of the seven support surfaces 26 ; 27 ; 28 , which are arranged side by side in the axial direction of the forme cylinder 01 , must be removed. In each case, it is the center support surface 26 ; 27 ; 28 which, in one of each of the three sequences of three support surfaces 26 ; 27 ; 28 , is arranged directly one in front of another. In other words, in each case, the support surface 26 ; 27 ; 28 having an even ordinal number, i.e., the second, fourth and sixth support surfaces 26 ; 27 ; 28 in this row of seven support surfaces 26 ; 27 ; 28 , embodied as guide rails and arranged parallel to one another is the one which must be removed.
The cross member 29 , that is shown schematically in FIG. 16 and in FIG. 17 , is connected, at each of its opposing end surfaces, to a positioning device 31 , and preferably is connected to a lifting device 31 . In another preferred embodiment, only a single positioning device 31 may be provided for the purpose of adjusting the spatial position of the cross member 29 , and including the storage compartments 22 ; 23 ; 24 connected to it, relative to the forme cylinder 01 . By synchronously actuating the positioning devices 31 , which are shown in FIG. 16 and FIG. 17 , the levels of the respective support surfaces 26 ; 27 ; 28 , each of which is permanently connected to the cross member 29 , and thus also the levels of each of the respective storage compartments 22 ; 23 ; 24 , can be adjusted. In the preferred embodiment, the lifting device 31 raises or lowers the cross member 29 , along with the storage compartments 22 ; 23 ; 24 attached to it, preferably as a combined unit, in other words, simultaneously in the same lifting process. However, the lifting device 31 must only simultaneously raise or lower at least two, and preferably all, support surfaces 26 ; 27 ; 28 that are connected to the cross member 29 . The positioning or lifting device 31 therefore adjusts, or can adjust, the respective storage compartments 22 ; 23 ; 24 alternatingly, for example, to at least two different stable spatial positions. By use of the positioning device 31 , or by use of the at least one positioning device 31 , at least one opening area of at least two of the storage compartments 22 ; 23 ; 24 , with that opening area facing the forme cylinder 01 , can be and actually is adjusted, in its respective operating state of engagement against the forme cylinder 01 , to the same spatial position relative to the forme cylinder 01 at different points in time. The opening area of a storage compartment 22 ; 23 ; 24 extends along a boundary of the relevant storage compartment 22 ; 23 ; 24 , with that boundary facing the forme cylinder 01 and extending axially along it. This boundary of the relevant storage compartment 22 ; 23 ; 24 faces the forme cylinder 01 , and thus extends preferably parallel to the width of the printing forme 08 that is or that will be stored in the relevant storage compartment 22 ; 23 ; 24 , with that width of the printing forme extending in the axial direction of the forme cylinder 01 . One of the opening areas of a selected one of the preferably three, vertically stacked storage compartments 22 ; 23 ; 24 is therefore adjusted either to the infeed plane of the printing forme 08 that is to be supplied to the forme cylinder 01 or to the infeed plane of the printing forme 08 that is to be removed from the forme cylinder 01 . The respective support surface 26 ; 27 ; 28 , belonging to the relevant storage compartment 22 ; 23 ; 24 , and depending upon the operational setting of the storage compartment, which is selected using the at least one adjustment device 31 , is arranged so that the respective opening area of the relevant storage compartment 22 ; 23 ; 24 is positioned at the same spatial position as one of these infeed planes. This thereby allows unimpeded conveyance of the relevant printing forme 08 away from, or up to the forme cylinder 01 . This can be accomplished without a staged offset between this respective infeed plane and the relevant storage compartment 22 ; 23 ; 24 with the associated support surface 26 ; 27 ; 28 in the vertical direction of the respective infeed plane. Each respective infeed plane extends at least between the opening area of the relevant storage compartment 22 ; 23 ; 24 and the circumferential surface of the forme cylinder 01 . Each such infeed plane is thus located tangentially against the circumferential surface of the relevant forme cylinder 01 . A transport path for the printing forme 08 to be loaded or removed, and existing between the relevant storage compartment 22 ; 23 ; 24 and the relevant forme cylinder 01 , extends, in each case, within or at least along the respective infeed plane. An area that is spanned by the respective support surface 26 ; 27 ; 28 , such as, for example, an area between a pair of guide rails of the relevant storage compartment 22 ; 23 ; 24 , which guide rails are arranged spaced from and parallel to one another, and the respective infeed plane of the printing forme 08 that is stored or at least will be stored in this storage compartment 22 ; 23 ; 24 therefore have, at least in their transition area, such as, for example, in the opening area of the relevant storage compartment 22 ; 23 ; 24 , which faces the relevant forme cylinder 01 , a continuous, preferably linear shape for the passage of the relevant printing forme 08 that is to be conveyed away from, or up to the forme cylinder 01 . Preferably, the at least one positioning device 31 adjusts at least two of the storage compartments 22 ; 23 ; 24 as a combined unit, typically along its entire length, and at different times, to the same spatial position relative to the forme cylinder 01 . The at least one positioning device 31 thus shifts the respective support surfaces 26 ; 27 ; 28 of at least two of the storage compartments 22 ; 23 ; 24 parallel with one another. This is the case especially when the relevant support surface 26 ; 27 ; 28 , with its respective storage compartment 22 ; 23 ; 24 , is permanently or rigidly connected in the magazine.
The respective storage compartments 22 ; 23 ; 24 , or at least their respective opening areas, thus have at least a first, for example, a lowered, stable operating position and have a second, for example, a raised, stable operating position. The at least one positioning device 31 can also pivot at least the opening area of each respective storage compartment 22 ; 23 ; 24 around a rotational axis that extends in the axial direction of the forme cylinder 01 . With this pivoting movement, the positioning device 31 adjusts the desired spatial position of the relevant storage compartment 22 ; 23 ; 24 , or at least the position of its opening area, relative to the forme cylinder 01 . The rotational axis, around which at least the opening area of the respective storage compartment 22 ; 23 ; 24 can pivot, is spaced from the boundary of the relevant storage compartment 22 ; 23 ; 24 , which faces the forme cylinder 01 and extends in the axial direction of the forme cylinder 01 .
At least the storage compartments 23 ; 24 in which the printing formes 08 that are to be loaded sequentially on the same forme cylinder 01 are stored, and preferably all of the storage compartments 22 ; 23 ; 24 in this device, which device is engaged against the same forme cylinder 01 , preferably form a combined unit, such as, for example, an integrated unit, in which the respective storage compartments 22 ; 23 ; 24 of this device are lowered or are raised together. The path of adjustment, which is preferably the stroke of the lifting device 31 , is indicated in FIG. 16 and in FIG. 17 by a double arrow. The stroke of the lifting device 31 lies within the range of, for example, a few millimeters, such as, for example, in a range between 5 mm and 30 mm, and especially lies in a range between 10 mm and 20 mm. The lifting device 31 can be embodied, for example, as one or more pneumatic cylinders. The support surfaces 26 ; 27 ; 28 , which are connected to the cross member 29 , can be implemented, for example, as U-shaped guide rails on which the printing formes 08 , which are stored in the storage compartments 22 ; 23 ; 24 , rest. At least one, and preferably both, of their respective edges, that extend parallel to the length of these printing formes 08 , are received in the spaced, LL-shaped guide rails.
Referring again now to FIGS. 1-15 , at least one conveyor device 32 , for use in conveying the respective printing forme 08 away from the forme cylinder 01 , is provided. This conveyor device 32 conveys a printing forme 08 , that is to be loaded into this storage compartment 22 , for example, by pulling it, via a movement which is executed along the length of the first storage compartment 22 assigned to the conveying device. This is done once the suspension leg 11 , which was located at the trailing end of this printing forme 08 , has been released from the opening 14 in the groove 13 and has been fed to the opening of this first storage compartment 22 as a result of a rotational movement of the forme cylinder 01 , optionally with the assistance of the guide element 19 , as may be seen in FIG. 1 . The rotational movement of the forme cylinder 01 is indicated in FIG. 1 by a rotational direction arrow. The conveyor device 32 has a carrier 33 , which may be embodied, for example, as a latch, and in which carrier 33 the suspension leg 11 , which is situated at the trailing end of the printing forme 08 to be loaded, engages, and especially snaps into, as a result of the rotational movement of the forme cylinder 01 . Once the carrier 33 of the conveyor device 32 has gripped the trailing suspension leg 11 , which is located at the trailing end of the printing forme 08 that is to be removed 08 , the carrier 33 is moved by the conveyor device 32 from a position which is close to the forme cylinder 01 to a position which is distant from the forme cylinder 01 . This movement results in the removal of the printing forme 08 that is to be removed completely from the forme cylinder 01 lengthwise. The removed printing forme 08 is drawn into the first storage compartment 22 , as seen in FIG. 2 and in FIG. 3 . FIG. 2 shows the printing forme 08 during its removal from the forme cylinder 01 , whereas FIG. 3 shows the printing forme 08 having been completely removed.
In the opening area of the first storage compartment 22 , and specifically at its end that faces the forme cylinder 01 , a ramp 34 can be provided, on which ramp 34 the leading end of the printing forme 08 rests when this printing forme 08 is stored in the first storage compartment 22 , as is seen in FIG. 3 . The closest position of the carrier 33 of the conveyor device 32 , with respect to the forme cylinder 01 , and when the printing forme 08 is to be removed, is located, for example, approximately halfway along the length of the printing forme 08 which is to be stored in this first storage compartment 22 . In order to support the release of the preferably acutely angled suspension leg 09 at the leading end of this printing forme 08 , that is eventually to be removed from the groove 13 of the forme cylinder 01 , it can be provided that, once the trailing end of the printing forme 08 , which is to be removed from the forme cylinder 01 , has been introduced into the first storage compartment 22 , at least this first storage compartment 22 is lowered relative to a spatial position of the forme cylinder 01 defined by the cylinder groove 13 . This lowering of the first storage compartment may be accomplished by actuating the at least one lifting device 31 , so that a bending stress is exerted on the front end of this printing forme 08 to be removed.
Once the printing forme 08 that is to be removed has preferably been completely drawn lengthwise into the first storage compartment 22 , at least this first storage compartment 22 is raised to another level. This elevating of the first storage compartment 22 may be accomplished especially by actuating the at least one lifting device 31 of the cross member 29 . The result is that the suspension leg 11 at the trailing end of the printing forme 08 to be removed becomes unlatched from the carrier 33 of the conveyor device 32 which remains stationary, as seen in FIG. 4 . The carrier 33 of the conveyor device 32 can then be moved back to its position close to the forme cylinder 01 , which position is depicted in FIG. 5 . If a second printing forme 08 is to be removed from the same axial position on the forme cylinder 01 , this second printing forme 08 is released from the forme cylinder 01 at its trailing end 11 , as was described above, and is also fed to the first storage compartment 22 . In this case, at least this first storage compartment 22 is now again lowered to its lower level, such as for example, by re-actuating the at least one lifting device 31 of the cross member 29 . The carrier 33 of the conveyor device 32 now again projects into the first storage compartment 22 , as is depicted in FIG. 8 . The carrier 33 of the conveyor device 32 can have a ram 36 , with which the removed printing forme 08 , which has already been stored in the first storage compartment 22 can be elevated. The result is that the already removed printing forme 08 is raised such that the leading end of this previously removed and stored printing forme 08 is raised from its position of rest an the ramp 34 . The trailing end of the second printing forme 08 , that is to be removed from the forme cylinder, can then be pushed, by the rotational movement of the forme cylinder 01 , under the leading end of the first, previously removed printing forme 08 that has already been stored in the first storage compartment 22 . The suspension leg 11 at the trailing end of the second printing forme 08 to be removed is moved into the storage compartment 22 until it is engaged on the carrier 33 of the conveyor device 32 , as is depicted in FIG. 7 . The second printing forme 08 to be removed from the forme cylinder 01 is then drawn all the way into the first storage compartment 22 by a movement of the carrier 33 of the conveyor device 32 to its position distant from the forme cylinder 01 . The second printing forme 08 to be removed is stored below the first removed printing forme 08 that was first stored in the first storage compartment 22 . The leading end of the second removed printing forme 08 is now resting on the ramp 34 , as seen in FIG. 8 . The first storage compartment 22 is now raised back up to its higher level, by a further actuation of the at least one lifting device 31 of the cross member 29 . The suspension leg 11 at the trailing end of the second printing forme 08 to be removed now also becomes unlatched from the carrier 33 of the conveyor device 32 , as may be seen in FIG. 9 . The removal process has now been completed for a specific axial position of the forme cylinder 01 . The two removed printing formes 08 that have now been stored in the first storage compartment 22 can be removed from the magazine, for example by staff who are operating the rotary printing press. The first storage compartment will thus be rendered empty, as may be seen in FIG. 10 .
By utilizing the above-described plate removal process, for example, the two mounting positions, which are provided at the same axial position on the forme cylinder 01 , and which are situated one in front of another in the forme cylinder's circumferential direction, for example, are vacated. These two mounting positions can now each be loaded with a new printing forme 08 in a subsequent plate loading process. For this purpose, one printing forme 08 to be loaded can stored in the second storage compartment 23 and a second printing forme 08 can be stored in the third storage compartment 24 , all as seen in FIG. 11 ; in FIG. 16 ; and in FIG. 17 .
The plate removal process has been described above within the context of an embodiment in which the level of the first storage compartment 22 can be changed by actuating the at least one lifting device 31 of the cross member 29 . However, because the execution of the above-described functions involves only a relative movement between the first storage compartment 22 and especially the carrier 33 of the conveyor device 32 , as an alternative to the above-described embodiment, the level of this carrier 33 of the conveyor device can also be adjustable relative to a stationary first storage compartment 22 . For executing functions, with respect to a printing forme 08 to be loaded, and which printing forme 08 to be loaded is stored in the second storage compartment 23 or in the third storage compartment 24 , a forme advancing mechanism 37 is provided. A level of the forme advancing mechanism 37 , which is indicated by reference numeral in FIG. 11 , is adjustable relative to these second and third storage compartments 23 ; 24 . The relative movement between the advancing mechanism 37 and the storage compartments 23 ; 24 will be described, by way of example, in the discussion which follows, again within the context of an actuation of the at least one lifting device 31 of the cross member 29 .
The advancing mechanism 37 , as may be seen in FIG. 11 , has a sliding element 38 , which first engages solely on the printing forme 08 , which is stored in the third, uppermost storage compartment 24 , and preferably engages the suspension leg 11 at the trailing end of the printing forme 08 which is stored in this third storage compartment 24 . This engagement is a result of the selected level between the advancing mechanism 37 and the storage compartments 23 ; 24 . The sliding element 38 , which is connected to the advancing mechanism 37 , projects vertically, for example, into the third storage compartment 24 . The advancing mechanism 37 , when it is actuated, exerts a thrust force via its slider element 38 on this printing forme 08 , with that thrust force being directed parallel to the longitudinal direction of the printing forme 08 to be loaded. This thrust force is applied in order to feed this printing forme 08 toward the forme cylinder 01 . Such a forward feeding is continued until the angled suspension leg 09 , at the leading end of this printing forme 08 to be loaded, engages in one of the openings 14 in one of the two grooves 13 of the forme cylinder 01 , which two grooves are arranged offset 180° from one another, as seen in FIG. 11 , and in FIG. 12 . The advancing mechanism 37 thus moves its slider element 38 from a position that is initially relatively distant from the forme cylinder 01 to a position that is relatively closer to the forme cylinder 01 . This relatively closer position is located in the area of the rear half, or even in the area of the rear third of the printing forme 08 to be loaded, and which printing forme 08 is preferably stored lengthwise in the third storage compartment 24 . Once the suspension leg 09 at the leading end of this printing forme 08 to be loaded becomes hooked on the forme cylinder 01 , the forme cylinder 01 then rotates in the direction which is indicated in FIG. 12 by a directional arrow. This rotation is effective in drawing the printing forme 08 to be loaded onto the circumferential surface of the forme cylinder 01 . The plate loading process can be supported by the at least one contact pressure element 16 which may be engaged against the circumferential surface of the forme cylinder 01 .
Once the printing forme 08 to be loaded, which was previously stored in the third storage compartment 24 , has been fed to the forme cylinder 01 , the level of the slider element 38 is adjusted relative to the second storage compartment 23 . Preferably, by actuating the at least one lifting device 31 of the cross member 29 , this second storage compartment 23 is raised relative to the advancing mechanism 37 , preferably as an integrated unit. The slider element 38 , that is connected to the advancing mechanism 37 , now engages against the printing forme 08 which is stored in the second storage compartment 23 , and preferably engages against the suspension leg 11 at the trailing end of this printing forme 08 which is stored in this second storage compartment 23 . This engagement occurs with the slider element preferably situated in its position distant from the forme cylinder 01 , as may be seen in FIG. 13 . When it is actuated, the advancing mechanism 37 then exerts, via its slider element 38 , a thrusting force on the printing forme 08 to be loaded. That thrusting force is directed parallel to the longitudinal direction of this printing forme 08 , and is exerted in order to feed this printing forme 08 to the forme cylinder 01 in the same manner as was described above in reference to FIG. 11 and to FIG. 12 . Movement of the slider element 38 continues in the direction toward the forme cylinder 01 until the angled suspension leg 09 at the leading end of this printing forme 08 to be loaded on the forme cylinder 01 engages in one of the openings 14 in one of the grooves 13 of the forme cylinder 01 . Once this suspension leg 09 at the leading end of this printing forme 08 to be loaded becomes hooked on to the edge of the groove opening 14 , the forme cylinder 01 again rotates in the direction indicated by a directional arrow in FIG. 14 . This rotation draws the printing forme 08 to be loaded onto the circumferential surface of the forme cylinder 01 . The plate loading process can also be supported by the use of the at least one contact pressure element 16 that is engaged against the circumferential surface of the forme cylinder 01 . When a plurality of printing formes 08 are to be supplied to the forme cylinder 01 from different storage compartments 23 ; 24 , the slider element 38 of the advancing mechanism 37 always feeds the printing forme 08 that is stored in the one of the several storage compartment 23 ; 24 which requires the shortest adjustment path for the lifting device 31 to the forme cylinder 01 first. In other words, the slider element 38 of the advancing mechanism 37 projects at different depths into the device with the storage compartments 23 ; 24 , depending upon, for example, the selected spatial position of this device. In each case, the slider element 38 can optionally be placed in active connection with the suspension leg 11 of one of the printing formes 08 to be loaded by lowering that slider element relative to the storage compartment 23 ; 24 or by raising the storage compartment 23 ; 24 relative to the slider element 38 .
Once the respective printing formes 08 that are stored in each of the storage compartments 23 ; 24 have been fed to the forme cylinder 01 and have been mounted on the forme cylinder 01 , the slider element 38 that is connected to the advancing mechanism 37 is preferably moved back to its position that is more distant from the forme cylinder 01 . Slider element 38 may then be pivoted, for example, by a rotation of 45° or more away from the forme cylinder 01 , for example, as is indicated in FIG. 15 by a directional arrow. The storage compartments 23 ; 24 now become accessible for loading with new printing formes 08 . A new plate removal process and/or plate loading process, as has been described above, can then begin.
The present invention is characterized in that, either the at least one positioning device 31 adjusts at least one opening area, with that opening area facing the forme cylinder 01 , of at least two of the storage compartments 22 ; 23 ; 24 , in its respective operating state of engagement against the forme cylinder 01 , to the same spatial position relative to the forme cylinder 01 at different points in time, or alternatively, in that the at least one lifting or positioning device 31 raises the respective storage compartment 22 ; 23 ; 24 relative to the carrier 33 and/or relative to the slider element 38 , or lowers the carrier 33 and/or the slider element 38 relative to the respective storage compartment 22 ; 23 ; 24 . In the first embodiment of the present invention, the relevant storage compartments 22 ; 23 ; 24 are preferably adjusted, as a combined unit, to the same spatial position relative to the forme cylinder 01 at different points in time by adjusting the integrated unit provided by the magazine. In the second embodiment, in each of its two variations, a relative movement, which is directed preferably orthogonally to the relevant storage compartment 22 ; 23 ; 24 , is executed between this at least one storage compartment 22 ; 23 ; 24 and the carrier 33 and/or slider element 38 which is assigned to it. In this case, the at least one lifting or positioning device 31 preferably raises the respective storage compartment 22 ; 23 ; 24 as a combined unit relative to the carrier 33 and/or slider element 38 .
FIG. 18 through FIG. 24 show various arrangements of a device in accordance with the present invention, and as described above, in connection with FIG. 1 through FIG. 17 , with a plurality of storage compartments 22 ; 23 ; 24 , and especially with three such storage compartments, in variously configured printing units.
FIG. 18 schematically depicts a printing tower with two nine-couple satellite printing units arranged one above another. A device having a plurality of storage compartments 22 ; 23 ; 24 is arranged tangentially, in a horizontal alignment, on each forme cylinder 01 . The three storage compartments 22 ; 23 ; 24 are always arranged one above another in a stack or in a layered assembly. A path of a print substrate 39 , and especially a web of material 39 , and preferably a web of paper 39 , which is guided through the printing units, and the respective rotational direction of the printing couple cylinders, in their production direction, are each indicated by a rotational direction arrow. All of the printing couple cylinders are at least approximately the same size in diameter. The forme cylinders 01 and the transfer cylinders 42 , which are respectively assigned to them, are each embodied as double-sized cylinders. Two printing formes 08 can thus be arranged around the periphery of each respective forme cylinder 01 in the circumferential direction. An inking unit 07 and a dampening unit 41 are engaged against each respective forme cylinder 01 . The inking units 07 each have a roller train comprised of a plurality of rollers 02 ; 03 ; 04 ; 06 , as may be seen by referring back to FIG. 1 .
FIG. 19 also shows a printing tower with two nine-cylinder satellite printing units arranged one above the other. The forme cylinders 01 and the transfer cylinders 42 , which respectively are assigned to each satellite printing unit, are each embodied as double-sized cylinders. An inking unit 07 and a dampening unit 41 are engaged against each respective forme cylinder 01 . The inking units 07 each have a roller train which is preferably comprised of a plurality of rollers 02 ; 03 ; 04 ; 06 . All the printing couple cylinders are at least approximately the same size in diameter. In contrast to the devices represented in FIG. 18 , and which are provided with the plurality of storage compartments 22 ; 23 ; 24 , in this embodiment, only the second storage compartment 23 and the third storage compartment 24 form an integrated unit. The first storage component 22 , which receives the removed printing formes, is arranged separately and is positioned at an inclination of preferably less than 30°, for example, in relation to the other two storage compartments 23 ; 24 . The second storage compartment 23 and the third storage compartment 24 are arranged horizontally, for example, and preferably are positioned in a tangential alignment in relation to the forme cylinder 01 . The first or used plate storage compartment 22 can be arranged below or above the other two storage compartments 23 ; 24 . Depending upon the installation conditions in the printing couple, the respective device and the plurality of storage compartments 22 ; 23 ; 24 can also be arranged in a reverse sequence to the representations of FIG. 1 to FIG. 17 , in some cases even arranged upside down, on the respective forme cylinder 01 .
FIG. 20 also shows a printing tower with two nine-cylinder satellite printing units which are arranged one above the other. The forme cylinders 01 , and the transfer cylinders 42 which are respectively assigned to them, are each embodied as double-sized cylinders. An inking unit 07 and a dampening unit 41 are engaged against each respective forme cylinder 01 . In FIG. 20 , the respective rotational directions of the printing couple cylinders, and of the rollers which are provided for production operation are each indicated by rotational direction arrows. In contrast to the printing units shown in FIG. 18 and FIG. 19 , the diameter of the impression cylinder 43 in the two nine-cylinder satellite printing units of FIG. 20 is approximately 50% larger than that of the four transfer cylinders 42 which are engaged against it. In the printing units shown in FIG. 20 , as in the printing units which are shown in FIG. 19 , in the devices having the plurality of storage compartments 22 ; 23 ; 24 , only the second storage compartment 23 and the third storage compartment 24 form an integrated unit. The first storage compartment 22 is arranged separately and at an inclination of preferably less than 30°, for example, in relation to the other two storage compartments 23 ; 24 . The first storage compartment 22 can be arranged either below or above the other two storage compartments 23 ; 24 . The second storage compartment 23 and the third storage compartment 24 are preferably arranged in a tangential alignment relative to the forme cylinder 01 . They are engaged against the respective forme cylinder 01 at an angle of inclination of between 15° and 75°, and preferably of between 40° and 60°, from the horizontal.
FIG. 21 to FIG. 24 are directed to arrangements of the devices each having the multiple storage compartments 22 ; 23 ; 24 , and each being situated in a printing tower with printing couples arranged one above the other, such as, for example, in a compact structured eight-couple tower, which can be used in a double-sided, for example four-color, printing process. In FIG. 21 and in FIG. 22 , the printing couple cylinders, i.e., the forme cylinders 01 and the respectively assigned transfer cylinders 42 , are each double-sized in configuration. The devices with the plurality of storage compartments 22 ; 23 ; 24 are each preferably arranged generally horizontally and in a tangential alignment with each respective forme cylinder 01 . The three storage compartments 22 ; 23 ; 24 each form an integrated unit that is corresponding to the representations in FIG. 1 through FIG. 17 , for example. Each inking unit 07 , which is engaged against its respective forme cylinder 01 , is embodied as an anilox inking unit, for example. The printing unit has two halves 44 ; 46 which may be encompassed by a frame 47 , for example, with at least one half 44 or 46 of the printing unit being mounted so as to be capable of moving toward or away from the other half 46 ; 44 , respectively of the printing unit. FIG. 22 shows the printing unit of FIG. 21 with one printing unit half 44 ; 46 moved away from the other. The printing units which are represented in FIG. 23 and FIG. 24 differ from the printing units which are represented in FIGS. 21 and 22 . The printing units depicted in FIG. 23 and in FIG. 24 show single-sized forme cylinders 01 , which each cooperate with double-sized assigned transfer cylinders 42 . In FIG. 23 , the inking unit 07 that is engaged against each respective forme cylinder 01 is embodied, for example, as a short inking unit such as, for example, as an anilox inking unit. The respective inking unit 07 in the printing unit of FIG. 24 has a longer roller train. In the printing unit of FIG. 24 a dampening unit 41 is also engaged against each respective forme cylinder 01 . In FIG. 23 and in FIG. 24 , the devices with the plurality of storage compartments 22 ; 23 ; 24 are also each arranged either horizontally or at an inclination of up to 15°, and preferably of less than 10° from horizontal in relation to the respective forme cylinder 01 , and are each positioned at a tangential alignment, in relation to the respective forme cylinder 01 . The three storage compartments 22 ; 23 ; 24 again form an integrated unit corresponding to the representations in FIG. 1 through FIG. 17 , for example. The printing units of FIGS. 23 and 24 can also have printing unit halves 44 ; 46 that can be separated by moving them apart.
While preferred embodiments of devices comprising a plurality of storage compartments arranged spaced from one another, in accordance with the present invention, have been set forth fully and completely hereinabove, it will be apparent to one of skill in the art that various changes in, for example, the specific drives for the cylinders, the structures of the frames of the printing units, the types of inks being applied to the webs and the like could be made without departing from the true spirit and scope of the subject invention which is accordingly to be limited only by the appended claims. | At least several spaced apart storage compartments are provided in a plate storage device. These compartments can receive used printing forms from a printing cylinder or new printing forms that are to be supplied to the printing cylinder. At least one positioning assembly is utilized to adjust at least one mouth region of two of the storage compartments to the same spaced position, with respect to the printing cylinder, at different times in the operating cycle of the plate storage compartments. This mouth region is situated facing the printing cylinder. In another embodiment, at least one printing form, that is being received from the printing cylinder, can be stored in at least one storage compartment. At least one conveying apparatus is provided and includes an entraining mechanism for gripping the printing form that is to be removed. Alternatively, the conveying apparatus can be used with a new printing form that is to be fed to the printing cylinder and which is stored in at least one of the storage compartments. At least one advancing mechanism is provided and is comprised of a slider that can grip the printing form that is to be fed. A positioning assembly lifts and lowers the storage compartment, relative to the entraining mechanism and/or the slider or lifts and lowers the entraining mechanism and/or the slider relative to the storage compartment. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation under 35 U.S.C. §120 of prior U.S. application Ser. No. 13/388,259, filed on Jan. 31, 2012, which is a National Stage entry under 35 U.S.C. 371(c) of International Application No. PCT/JP2010/062569, filed on Jul. 27, 2010, which in turns claims priority to Japanese Application No. 2009-179143, filed on Jul. 31, 2009, the entire disclosures of which are incorporated herein by reference.
BACKGROUND
[0002] The present invention relates to a method for packaging medical supplies.
Background Art
[0003] The medical supplies such as surgical suture thread and suture needles are contained in a packaging bag after production, and are sterilized and then stored. When using, the packaging bag is opened and the medical supplies are taken out and then used.
[0004] The medical supplies are manufactured and contained in a packaging bag until use, which is not a constant period but storage is often a long time as well. Therefore, the sterilized state needs to be maintained throughout the storage period. A bacteria impermeable film is used for the packaging bag for this purpose.
[0005] Moreover, disinfection is conducted using sodium hypochlorite, hydrogen peroxide, and the like in hospitals, and these disinfectants may penetrate into the packaging bag. Since the packaging bag uses a bacteria impermeable film, introduction of a disinfectant is not required. Rather, it is preferable that the disinfectants do not penetrate into the packaging bag. This is because since these disinfectants have a bleaching action and the medical supplies are colored for identification, the colored medical supplies would be bleached.
[0006] Patent Document 1 (JP H05-82221B) is well-known as a conventional packaging bag containing medical supplies. This has a double bag structure.
[0007] FIGS. 3A-3C illustrate the packaging bag for medical supplies disclosed in Patent Document 1, where FIG. 3A is a top view, FIG. 3B is a cross section of FIG. 3A , and FIG. 3C is a top view illustrating a state without unnecessary parts. As shown in these drawings, medical supplies 1 are contained in an inner bag 2 , and the inner bag 2 is contained in an outer bag 6 , thereby constituting a double bag structure.
[0008] The medical supplies 1 in Patent Document 1 include surgical suture thread, staples, sponges, pins, prosthetic skin, or the like, and are hydrolyzable or able to enter the body and breakdown by moisture.
[0009] The inner bag 2 uses a heat-sealable plastic film 3 , which is gas and bacteria impermeable, and a film 4 , which is gas permeable and bacteria impermeable. The periphery of the films 3 and 4 is heat sealed except for an opening thereof, thereby forming a seal part 5 a. The medical supplies 1 are contained in such an inner bag 2 , the opening is heat sealed to form a seal part 5 b, and then sealed.
[0010] This inner bag 2 is then placed inside the outer bag 6 . The outer bag 6 is consisted of a film resulting from coating metal foil such as aluminum with heat-sealing resin, or laminating a resin film on metal foil such as aluminum. One of openings of the outer bag 6 is provided with a gas permeable and bacteria impermeable film 7 . The periphery of the outer bag 6 is heat sealed except for an opening thereof, thereby forming a seal part 8 a. The inner bag 2 is placed in the outer bag 6 and the opening is heat sealed to form a seal part 8 b. FIGS. 3A and 3B illustrate this state.
[0011] The sterilization method of the medical supplies 1 is as follows.
[0012] A sterilizing gas such as ethylene oxide gas (EO gas) or the like is supplied to the entire outer bag 6 . The sterilizing gas enters into the outer bag 6 via the film 7 , sterilizing the inner surface of the outer bag 6 and the outer surface of the inner bag 2 . The sterilizing gas also enters into the inner bag 2 via the gas permeable film 4 , sterilizing the stored medical supplies and the inner surface of the inner bag 2 .
[0013] After this, the double bag is placed in a vacuum device, degasification is performed, the sterilizing gas is discharged, and it is dried by a drying furnace, thereby removing the sterilizing gas and moisture from the outer bag 6 and the inner bag 2 . Heat sealing is conducted at a position slightly deviant from the film 7 of the outer bag 6 , and as shown in FIG. 3C , a seal part 8 c is formed and the film 7 portion is cut off, thereby completing the process.
PRIOR ART DOCUMENTS
Patent Documents
[0014] [Patent Document 1] JP H05-82221B
DISCLOSURE OF INVENTION
Problem to be Solved by the Invention
[0015] However, since the packaging bag shown in FIGS. 3A-3C is made of a film of metal foil such as aluminum laminated on both front and back surfaces of the outer bag 6 , the inside cannot be seen. Therefore, what the stored medical supplies are cannot be visually confirmed.
[0016] While both the inner bag 2 and the outer bag 6 need only to be transparent synthetic resin films in order to be able to see inside, normally, such a film transmits not only O2, but sodium hypochlorite (NaClO) and hydrogen peroxide (H2O2) for sterilization as well.
[0017] In the case where the medical supplies 1 is suture thread, colored suture thread is normally used in order to display type, thickness, and the like of the suture thread. However, NaClO and H2O2 have disinfecting power and bleaching power, and when they penetrate into the inner bag, the color of the suture thread is bleached, whereby making the type of the suture thread indiscernible. Moreover, the suture thread is weakened by the bleaching chemical action.
[0018] The present disclosure, in light of the current condition, aims to provide a packaging bag, which allows visual confirmation of the content yet does not bleach medical supplies contained therein, a packaging bag containing medical supplies, and a packaging method for medical supplies.
[0019] A method of packaging medical supplies according to the present disclosure comprises the steps of overlapping a front film onto a back film, at least one of the front film and the back film being transparent and bacteria impermeable and does not transmit molecules as large as or larger than O2, extending a material that is gas permeable and bacteria impermeable along an opening side of at least one of the front film and the back film, and sealing the periphery of the front film and the back film except for the opening to form a packaging bag; inserting medical supplies in the packaging bag and then sealing the opening side; sterilizing an interior of the packaging bag with EO gas injected through the material that is gas permeable and bacteria impermeable, removing the gas after sterilization using a vacuum device or by exchanging the gas with another gas, and drying by dry heat or air drying; and sealing the packaging bag so that the material that is gas permeable and bacteria impermeable does not communicate with the inside of the packaging bag. Preferably, the transparent film that is bacterial impermeable and does not transmit molecules as large as or larger than O2 is a plastic film coated with silica or alumina
[0020] According to the present invention, even if the packaging bag is exposed to H2O2 or sodium hypochlorite for disinfection after medical supplies are sealed therein, the H2O2 or sodium hypochlorite will not enter the packaging bag and may thereby prevent bleaching of the medical supplies. Moreover, since the films are transparent, content may be confirmed from the outside, which is an excellent result.
BRIEF DESCRIPTION OF DRAWINGS
[0021] FIGS. 1A-1C illustrate a working example of the present invention, where FIG. 1A is a top view of a packaging bag for medical supplies according to the present invention, FIG. 1B is a central cross section of FIG. 1A , and FIG. 1C is a top view of a state where medical supplies are contained in the packaging bag for medical supplies according to the present invention and sealed therein;
[0022] FIG. 2 illustrates a working example of the present invention; and
[0023] FIGS. 3A-3C illustrate a conventional packaging bag for medical supplies, where FIG. 3A is a top view, FIG. 3B is a cross section of FIG. 3A , and FIG. 3C is a top view illustrating a state without unnecessary parts.
DETAILED DESCRIPTION
[0024] Embodiments according to the present invention are described with reference to accompanying drawings forthwith.
[0025] FIGS. 1A-1C illustrate a working example of the present invention, where FIG. 1A is a top view of a packaging bag for medical supplies according to the present invention, FIG. 1B is a central cross section of FIG. 1A , and FIG. 1C is a top view of a state where medical supplies are contained in the packaging bag for medical supplies according to the present invention and sealed therein.
[0026] In general, various synthetic resin films such as PET, polypropylene, and nylon are gas permeable, and have a property of transmitting O2, of course, as well as hydrogen peroxide, sodium hypochlorite, and the like. The inventors of the present invention have found that deposition of silica and alumina on various synthetic resin films such as PET, polypropylene, and nylon allows achievement of a characteristic of not transmitting hydrogen peroxide and sodium hypochlorite while transmitting oxygen marginally, whereby this knowledge has lead to the completion of the present invention. Deposition methods for silica and alumina utilize PVD and CVD.
[0027] Note that whether the film on which silica and alumina are deposited allows transmission can be thought to depend on the magnitude of the molecular weight thereof. Namely, the molecular weight of oxygen is 32, the molecular weight of hydrogen peroxide is 34, and the molecular weight of sodium hypochlorite is 74, and the film transmits those with smaller molecular weights than 32, where hydrogen peroxide and sodium hypochlorite with molecular weights greater than 32 are not transmitted as they are greater than the molecular weight of oxygen.
[0028] While it has been said that the film does not transmit oxygen, hydrogen peroxide, and sodium hypochlorite, this is not meant in the strictest sense. Oxygen may be marginally transmitted, and hydrogen peroxide and sodium hypochlorite are only more difficult to be transmitted than oxygen, which does not mean that they are not transmitted through at all. However, since quantities of transmitting hydrogen peroxide and sodium hypochlorite are extremely minute, they are negligible. According to the inventors' experiment, favorable results were found when oxygen transmittance is 0.11 (cm3/m2 day·atm) or less under a condition of 23 degrees Celsius and 65% RH. Description of this experiment will be given as a working example.
[0029] As shown in FIGS. 1A and 1B , a packaging bag 10 for medical supplies according to the present invention has a front side film 11 and a backside film 12 . Both the front side film 11 and the backside film 12 are various synthetic resin films such as polypropylene or nylon on which silica and alumina are deposited, maintaining a transparent state.
[0030] In the working example of FIGS. 1A-1C , the front side film 11 and the backside film 12 are both transparent and utilize the same material, but are not limited thereto. A transparent film on which silica or alumina is deposited should be used on at least one side. For example, either the front side film 11 or the backside film 12 may be a film made by laminating or coating a heat-sealing resin on metal foil such as aluminum.
[0031] A film 13 made of a gas permeable, bacteria impermeable material is extended along an opening side (upper end in the drawing) of the front side film 11 . These films 11 to 13 are heat sealable, and left, right, and lower portions are heat sealed so as to form a seal part 16 a, thereby forming a bag shape. Alternatively, one sheet may be folded over at the central portion and sealed on two sides so as to form a bag shape. The medical supplies 15 are contained in this packaging bag 10 , and the upper opening in the drawing is heat sealed to form a seal part 16 b. When the seal part 16 b is formed by folding one sheet, three sides are sealed. The medical supplies 15 are not particularly limited as long as they are for medical use. The medical supplies 15 are contained in a packaging bag in the above description, and sterilization processing will be executed next.
[0032] The sterilization processing is as follows.
[0033] A sterilizing gas such as EO gas (ethylene oxide gas) or the like is supplied to the entire packaging bag 10 . The sterilizing gas enters into the packaging bag 10 via the film 13 , which is at the opening rim of the packaging bag 10 , sterilizing the inner and outer surfaces of the packaging bag 10 and the contained medical supplies 15 .
[0034] After this, the packaging bag 10 is placed in a vacuum device, degasification is performed, the sterilizing gas is discharged, and it is dried by a drying furnace, thereby removing the sterilizing gas from the packaging bag 10 . The sterilizing gas removal method, aside from the above method, may also be a method of exchanging it with another gas such as air, or a method of adding dry heat so as to dry it. Dry-heat sterilization is a sterilization method of thermal denaturalization and devitalization of microorganisms, enzymes, and proteins by heating at 160 to 200 degrees Celcius for 30 minutes to 2 hours. Once the sterilizing gas is removed, the films 11 and 12 are heat sealed at a position where the film 13 of the packaging bag 10 does not communicate with the inside of the packaging bag 10 , thereby forming a seal part 16 c as shown in FIG. 1C , and the film 13 portion is then cut off, completing the process. If the seal portion 16 c is formed, cutting off the film 13 portion may be omitted.
[0035] If the packaging bag in this state is stored at a hospital or the like, even if disinfection is carried out at the hospital using hydrogen peroxide and sodium hypochlorite, hydrogen peroxide and sodium hypochlorite no longer enters the packaging bag 10 , thereby allowing prevention of trouble such as suture thread being decolorized.
[0036] FIG. 2 is a working example where the packaging bag 10 containing the medical supplies 15 shown in FIGS. 1A-1C is contained in a larger, outer packaging bag 10 ′ having the same constitution as the packaging bag 10 . The packaging bag 10 ′ has the same structure as the packaging bag 10 . An opening of the outer packaging bag 10 ′ containing the inner packaging bag 10 is heat sealed so as to form the seal part 16 b, sterilization processing is executed in the same manner as for the packaging bag 10 , and the seal part 16 c is formed, thereby allowing the same double bag structure as in Patent Document 1. In this case, since the films 11 and 12 result from silica and alumina deposited on transparent plastic films, transparency is assured, allowing easy confirmation of the medical supplies contained therein. Moreover, by making the film on the same side as the packaging bag 10 and the packaging bag 10 ′ be transparent in the case where one of the films 11 and 12 is a laminated film of metal foil such as aluminum or the like, the content may be visually confirmed even if it is a double bag structure.
[0037] While the packaging bag 10 and the packaging bag 10 ′ have the same structure, this same structure referred to here means functionally the same structure, and the packaging bag 10 and the packaging bag 10 ′ are not limited to being made of the same material.
[0038] The packaging bag 10 of the present invention produces improvements, such that contents may be visually confirmed if the films are PET coated with silica, chlorine gas is not generated even if it is burned after disposal, there is hardly any residue after burning, and it may be lighter than a film using aluminum foil.
[0039] Note that a transparent film that does not transmit any oxygen may be manufactured depending on type of plastic, deposition method of silica and alumina, and the like. If a film that does not transmit oxygen is used, the bag may be used for packaging hydrolyzable medical supplies.
WORKING EXAMPLE 1
[0040] Table 1 shows results from an experiment using four types of packaging bags A, B, C, and D. In Table 1, thickness (μm) is thicknesses of the films 11 and 12 constituting the packaging bag 10 for medical supplies, where 50+80 denotes that thickness of the film 11 is 50 micrometers and that of the other film 12 is 80 micrometers. Both of these films have used a film on which silica is deposited on each side.
[0000]
TABLE 1
Oxygen
7 days later
14 days later
Thickness
transmission
Change
Change
Sample
(μm)
(cm3/m2day)
in color
Strength
in color
Strength
A
80 + 80
0.06
⊚
44.7
⊚
45.3
B
50 + 80
0.09
⊚
44.2
Δ
40.8
C
80 + 80
0.13
Δ
39.5
X
19.7
D
50 + 80
0.20
X
33.8
X
16.1
Control
—
—
⊚
44.1
⊚
44.1
⊚ No decolorization
Δ Slight decolorization
X Decolorization
[0041] Oxygen transmittance (unit is cm3/m2·day·atm) is transmission between inside and outside the packaging bag 10 . Oxygen transmittance of both the film 11 and the film 12 is in a combined state.
[0042] Change in color means that whether or not decolorization has occurred has been visually determined from change in color of the suture thread stored in the packaging bag 10 .
[0043] The packaging bags 10 of the types A, B, C, and D contain the same suture thread, and each of the packaging bags 10 was kept in a state exposed to hydrogen peroxide in a plastic container. Tensile strength and decolorization were determined after seven days and fourteen days.
[0044] A control had been prepared for comparative purposes and had the suture thread contained in the packaging bags 10 of the types A, B, C, and D, but was not exposed to hydrogen peroxide.
[0045] Validity is investigated through comparison with the control, which has ideal quality having sufficient tensile strength without any change in color, as a reference for the experiment results.
[0046] After seven days, A and B exhibited no decolorization, which is the same result as with the control, C had slight decolorization, and D had greater decolorization. Tensile strengths for A to D were 44.7 gf, 44.2 gf, 39.5 gf, and 33.8 gf, respectively, A and B had 100% tensile strength against the control, and C and D had 90% and 77%, respectively.
[0047] After fourteen days, A exhibited no decolorization, which is the same result as with the control, B had slight decolorization, and C and D were completely decolorized. Tensile strengths for A to D were 45.3 gf, 40.8 gf, 19.7 gf, and 16.1 gf, respectively, and they had 100%, 93%, 45%, and 37% tensile strength against the control, respectively.
[0048] The above results are found to be proportional to oxygen transmittance through examination by the inventors. To summarize the above results, A (0.06 oxygen transmittance) attained the same results as the control, and is considered a favorable film having ideal quality. B (0.09 oxygen transmittance) had slight decolorization and the tensile strength was favorable, and is thereby acceptable. C (0.13 oxygen transmittance) and D (0.20 oxygen transmittance) had complete decolorization as well as remaining strength was half or less than the control after fourteen days, and are thereby unusable. It is understood therefrom that there is no problem in use as long as the film had an oxygen transmittance of at least 0.09. Moreover, favorable use may be expected as long as the film has an oxygen transmittance of approximately 0.11, with consideration of a possible error of 0.09.
[0049] Note that while silica-coated films have been used in the above working examples, the case of alumina coating may also be treated the same as the silica-coated film by setting the upper limit of oxygen transmittance to approximately 0.11.
DESCRIPTION OF REFERENCE NUMERALS
[0000]
10 : Packaging bag for medical supplies
11 : film (bacteria impermeable and does not transmit molecules of O2 or larger)
12 : film (bacteria impermeable and does not transmit molecules of O2 or larger)
13 : (gas permeable and bacteria impermeable) film
15 : Medical supplies
16 a: Seal part
16 b: Seal part
16 c: Seal part | A method of packaging medical supplies includes overlapping a front film onto a back film, at least one of the front and back film being transparent and bacteria impermeable and does not transmit molecules as large as or larger than O2, extending a material that is gas permeable and bacteria impermeable along an opening side of at least one of the front and back film, and sealing the periphery of the front and back films except for the opening to form a packaging bag; inserting medical supplies in the packaging bag and then sealing the bag; sterilizing an interior of the packaging bag with EO gas injected through the material that is gas permeable and bacteria impermeable, removing the gas after sterilization and drying; and sealing the packaging bag so that the material that is gas permeable and bacteria impermeable does not communicate with the inside of the packaging bag. | 1 |
This is a continuation of copending application Ser. No. 07/349,733 filed on May 9, 1989, now abandoned.
FIELD OF THE INVENTION
The invention relates to a retaining band for a magnetic core which is made up of multiple laminated thin strips.
BACKGROUND OF THE INVENTION
The magnetic core of an electrical transformer can be formed of a number of laminated thin strips of a material which can be readily magnetized. The core material, for example, can be silicon steel or Metglas (TM). To make the core, the magnetic strips are formed into a loop. This loop is in the form of a circular shape, and, if desired, thereafter it is formed into a rectangular shape. The joints of each lamination in the core are positioned in a prescribed attitude to enhance the magnetic qualities of the loop. After formation the core is annealed. It can then be assembled with a coil as a final step.
Metglas (TM) is an amorphous, crystalline material which is very brittle. Thus, the laminations in such a core need protection. If they are not properly protected and they are bumped, dropped or otherwise improperly contacted, they can shatter or deform. In either case, the transformer may not function properly as a result of the contact.
Thus, there is a need to retain the core laminations, and to surround and protect the laminations from bumping, dropping, or other contact. This can be accomplished with a retainer which protects the core through formation, annealing, and also after the core is assembled with a coil.
Several methods of retaining metallic transformer cores have been suggested in the prior art. In U.S. Pat. No. 4,673,907, a band which is tightened and then clipped at its free ends to hold it in place is used to hold clamping plates and insulating plates in place, which in turn retain a metallic core. U.S. Pat. No. 4,723,349 discloses interlocking joints 116, 118 which hold two U-shaped members in place, and which in turn retain a metallic core. Each interlocking joint uses a tongue-in-slot arrangement. U.S. Pat. No. 4,364,020 discloses a protective outer layer for a core assembly made of silicon steel to protect the core. In U.S. Pat. No. 4,663,605, flexible banding under tension clamps two plates spaced outwardly from two yokes, and the clamping forces are transmitted to the coil structures by paths which bypass a rectangular core. The band is preferably held in place by a clip 68.
A retaining system which is simple, inexpensive, and easy to use is described below.
SUMMARY OF THE INVENTION
The present invention includes a band for surrounding and protecting a magnetic core and a system to retain the band in place. The band is preferably made of a ductile iron-based material, such as mild steel, and is particularly useful for protection if the core is made of Metglas (TM). This material is brittle in nature.
The band is bent around the magnetic core, which may be of either circular, rectangular, or other shape, and the ends of the band are overlapped. At least one pair of substantially. parallel incisions extend from one edge of the band ends in the overlapping region and towards the center of the band. The incisions sever both pieces of material and form a tab therebetween. The tab can be bent over towards the center of the band to lock the band in place, and, if desired, it can be welded in the bent position for added locking effect.
A preferred embodiment of the band of the invention has two tabs on opposite edges of the overlapping region. However, the band can also include a greater or lesser number of tabs.
The invention will now be described in greater detail with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a magnetic core loop surrounded by a band and showing two oppositely facing tabs in locking position.
FIG. 2 is a perspective view of another embodiment of the invention in which the overlapping region has four tabs but with
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a band 10 is shown surrounding and protecting a substantially rectangular magnetic core loop 12 which, in this embodiment, is made of Metglas (TM). The ends of band 10 overlap to form a region of overlap 14. Region 14 has two tabs 16 and 18, one being formed in each edge of the overlapping band ends, and each being bent towards the center of band 10, thereby locking band 10 in the retaining position.
Band 10 is preferably made of a ductile iron based material, for example mild steel. Other ductile materials, such as stainless steel, silicon steel or bronze, may also be used. It is preferably no more than 28 gauge (0.0149 inch) in thickness, in order to facilitate bending it around core loop 12. The width of band 10 is preferably at least that of the core laminations. A band 10 of such dimensions adequately covers and protects the thin laminated strips of core 12.
Band 10 is preferably long enough to surround core 12 completely and provide sufficient overlap in region 14 to allow formation of the tabs. 11/2 inches of overlap is generally adequate to form two oppositely facing tabs 16 and 18 on a rectangular core with sides of a length of 5 inches to 24 inches or more. However, a larger overlapping region 14 may be desired if, for example, more tabs in the region are desired or needed, as described below.
The tabs are formed by cutting through band 10 at region of overlap 14. To form each tab, two substantially parallel cuts are made transversely to the edges of band 10. They can be made, for example, with needle nosed snips inserted between magnetic core 12 and band 10. The amorphous nature of the Metglas core allows the strips to bend to accommodate the snips in this fashion. The cuts have a depth and are spaced so as to produce a tab which can be bent over on the overlapping end of the band and will have sufficient strength to secure the band around the coil. For example, for a band on a square coil with sides of length from 5 inches to 24 inches which is 2 inches to twelve inches wide, the cuts may be about one-half inch apart and extend about one-half inch towards the center of band 10.
Tabs 16 and 18 lock band 10 into place around core 12 when their respective edges which are nearest the side of band 10 are bent over towards the center of band 10 and into locking position, as shown in FIG. 1. It can be seen that in this position, the edges of tabs 16 and 18 rest within slots 22 and 24, the slots being formed by the bending operation. Band 10 is thus locked into place and its perimeter dimension cannot expand.
In the locking position band 10 is secured around the thin, easily damaged laminations of core loop 12, and it helps prevent damage to these laminations. Band 10 also prevents core loop 12 from expanding out of the substantially rectangular shape shown.
Rather than having two oppositely facing tabs 16 and 18, two or more additional tabs (e.g., tabs 23 and 25 in FIG. 2) can be provided in overlap region 14. These additional tabs may be desired if repeated bending of tabs 16 and 18 weakens them. Repeated bending and unbending can take place during formation of core loop 12, as described below. Also, additional tabs may be desired if after annealing and assembling the core and coil, the core does not assemble as tightly as it did prior to annealing and the original tabs do not align accurately. This misalignment is shown for tabs 16 and 18 in FIG. 2.
Additional tabs may also be provided if additional locking force for band 10 is needed or desired. However, one could also use tabs which ar wider to increase the locking force.
In forming core loop 12, the laminated strips are first placed in the desired position. For example, the strips of the FIG. 1 embodiment would be placed in a substantially round or rectangular shape To retain them in this position, band 10, which is slightly longer than the periphery of core loop 12, is bent around the laminated strips, and the ends form overlap region 14, which can include tabs 16, 18, or additional tabs 23 and 25, as described above. Overlap region 14 can be adjusted so as to reside at any position on the perimeter of core 12, as needed for transformer design.
To retain band 10 in place, the tabs need not be fully bent and crimped against band 10. They can be partially bent, for example, to a position perpendicular to the surface of band 10, and still retain band 10 adequately. The only requirement is that they be bent enough to prevent the overlap region 14 from separating under the expanding force exerted by the elasticity of band 10.
It is necessary to anneal the laminated strips of core 12 to attain a properly functioning transformer. Band 10, with the tabs partially bent as described above, can retain the laminated strips during the annealing process. Thus, annealing is preferably carried out with the tabs in this partially bent position.
Following annealing, the tabs can be opened, and band 10 removed to allow core loop 12 to be assembled to the coils of a transformer. Such assembly is the final step in forming a transformer.
Following assembly to a coil, band 10 is bent around the laminated strips of core 12 to the point where the tabs match each other. The tabs can be fully bent over to lock band 10 in place or, if they are misaligned or worn from multiple bending, new or additional tabs can be cut and then bent. The new tabs may also provide added retaining strength.
The tabs can be locked into place by crimping them tight against the side of band 10. The tabs can also be locked by spot welding them in the approximate middle of the tab, as shown for spot 26 on tab 23 in FIG. 2. Welding bonds the two pieces of material forming the tab and aids in locking. Welding by a Tig or resistance method is preferred, as it is cleaner than regular arc welding.
The final assembled core-coil product has the fragile laminated strips held in place and protected by band 10. The product can be shipped with reduced fear of damage. Some advantages of using the retaining band of the invention include the fact that the mild steel band material is low cost, and it can be easily cut to the desired length. The ease with which it can be cut also aids in forming the tabs. It is noted that other materials, for example silicon steel, can be used for band 10. However, silicon steel is more difficult to weld than mild steel and is not preferred for this reason.
It should be understood that the embodiments described above are exemplary only and that many variations are possible and fall within the scope of protection, and further that the scope of protection is described only in the claims which follow and includes all equivalents of the subject matter of the claims | Disclosed is a retaining band for the magnetic core loop of an electrical transformer. The retaining band includes a locking mechanism to hold it in place around the core. The locking is accomplished by overlapping the ends of the band, cutting a pair of incisions in the overlapping region which extend from the sides of the band inwardly, and then bending the resulting tab(s) inwardly. If desired, the tabs can be spot welded to provide added locking force. | 8 |
[0001] This application claims priority to U.S. Provisional Application 61/774,279 filed Mar. 7, 2013, the entire contents being incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to an apparatus and method for trapping arthropods, particularly bed bugs and other insect pests.
BACKGROUND OF THE INVENTION
[0003] Several publications and patent documents are cited throughout the specification in order to describe the state of the art to which this invention pertains. Each of these citations is incorporated herein by reference as though set forth in full.
[0004] The bed bug, Cimex lectularius L. (Phylum Arthropoda, Class Insecta, Order Hemiptera, Family Cimicidae) has sucked the blood of humans for thousands of years (Panagiotakopulu & Buckland 1999). The tropical bed bug, Cimex hemipterus F., also has a long history of sucking the blood of humans in the tropics and subtropics. To complicate matters, there is a small group of related blood sucking bugs in the family Cimicidae including bat bugs and swallow bugs that will feed on humans and can be confused with human bed bugs. All of these human blood sucking bugs have no tarsal pads and can only climb a vertical surface by using tarsal claws hooked into a rough surface (Usinger 1966).
[0005] Bed bug adults are reddish-brown, oval, wingless, flattened insects about 6-9 mm long that are readily seen with the naked eye. Newly hatched bugs feed at the first opportunity. They molt five times before reaching maturity and require at least one blood meal between each molt. Bed bug adults often survive up to 2 months without food, but under certain circumstances can live a year or more without feeding. Bed bugs are active during the nighttime and hide during the daytime in tiny crevices or cracks. They rapidly move into a refuge when disturbed by light or air movement so they are rarely seen by the person who is bitten. Bed bugs are able to cling to possessions using tarsal claws and hide in small spaces so that they may easily be transported in a traveler's belongings (Usinger 1966).
[0006] Clearly, improved devices and methods for trapping bed bugs, thereby preventing unwanted bed bug infestations are highly desirable.
SUMMARY OF THE INVENTION
[0007] The invention provides a crawling arthropod intercepting device that can be placed under or adjacent to furniture (bed, sofa, chair, etc.) and other objects to intercept crawling arthropods including crawling insects and other crawling pests. An illustrative embodiment of the invention comprises an intercepting device that is adapted to be placed on a floor under a furniture leg (bed leg, sofa leg, chair leg, etc.) or climbable upstanding surface of other objects which may be or become infested in order to intercept crawling arthropods including crawling insects and other crawling pests and prevent them from moving between the furniture (or other object) and the floor. In another embodiment of the invention, the intercepting device can be placed on the floor adjacent furniture or other object to intercept crawling arthropods. The intercepting device can be used to monitor the presence of crawling arthropods including crawling insects and other crawling pests (such as bed bugs, ants, cockroaches, beetles, spiders, scorpions, etc.), reduce pest numbers, and monitor efficacy of pest control procedures.
[0008] A particular illustrative embodiment of the invention provides an intercepting device comprising at least a first exterior ( 1 ), upstanding climbable surface that crawling arthropods such as crawling insects can climb. The pitfall trap is disposed inwardly of said first ( 1 ) and a second ( 2 ) climbable exterior surface which facilitates trapping of crawling arthropods. The interior surface ( 3 ) is a smooth material, wherein crawling arthropods are trapped in the receptacle and prevented from crawling and moving between the furniture (or other object) and the floor. Each of said exterior surfaces is tactically attractive to crawling arthropods, and is a generally fibrous or otherwise rough surface thereby rendering the exterior surfaces readily climbable. In a preferred embodiment, the first and second exterior surfaces are dark colored. In another embodiment, the instant trap is in the general shape of a ring ( 4 ) or a square ( 5 ) and can be readily adapted to fit the leg or bed frame of a piece of furniture where arthropods are to be trapped. The traps can be of varying diameters ( 6 ) in order to accommodate furniture of different sizes. In another alternative embodiment, the trap may be made in two separate sections which can be affixed, or snapped together during application in order to utilize the trap on immovable or very large furniture pieces.
[0009] Crawling arthropods moving onto the device will fall into the trap and can be killed by an optional killing agent (soapy water, ethylene glycol, diatomaceous earth, etc.) provided in the pitfall trap and/or on the pitfall trap surfaces.
[0010] The present invention is advantageous and useful as a bed bug interception coaster device which serves to detect bed bugs approaching and departing the bed, sofa or other object and to monitor the efficacy of extermination efforts. The present invention also utilizes bed bug responses to the presence of a host, tactile surfaces, and gravity. Humans are effectively acting as bait for a trap.
[0011] Other advantages of the intercepting device of the present invention will become more readily apparent from the following detailed description taken with the following drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0012] FIG. 1 . Experimental set up for evaluate efficacy of the Insect Trap of the invention and Interceptor trap in trapping bed bugs moving away from furniture: a) Inventive Insect trap, and b) Climbup Insect Interceptor.
[0013] FIG. 2 . Experimental set up for evaluating efficacy of Inventive Insect Trap and Interceptor trap in trapping bed bugs moving toward furniture.
[0014] FIG. 3 . Efficacy of two traps for trapping bugs moving away from “furniture”.
[0015] FIG. 4 . Efficacy of two traps for trapping bugs moving toward “furniture”.
[0016] FIG. 5 . Different views of the trap of the invention
DETAILED DESCRIPTION OF THE INVENTION
[0017] Currently, there are very few effective and inexpensive bed bug monitors on the market. Climbup Insect Interceptor (Susan McKnight, Inc., Memphis, Tenn., USA) is one monitor that was found both inexpensive and effective for monitoring bed bugs (Wang et al. 2009 a,b; Wang et al. 2011). In accordance with the present invention, an improved trap design has been developed that provides higher trapping efficacy at lowered material cost compared to Climbup Insect Interceptor. This new design can also be used to trap other crawling arthropods.
[0018] The following example is provided to illustrate certain embodiments of the invention. It is not intended to limit the invention in any way.
Example I
Material and Methods
[0019] Bed bugs were collected from an infested apartment a few months prior to the tests. They were maintained in plastic containers at 26±1° C., 40±10% relative humidity, a 12:12 hour (L:D) photoperiod. The bed bugs were fed with rabbit blood using an artificial feeding system prior to the tests. Males and large nymphs were used. The bugs were 2-week hungry when conducting the study.
[0020] Plastic tray arenas (53 by 40 by 7 cm) (length by width by height) ( 7 ) with bottom lined with cotton fabric were used to evaluate the traps ( FIG. 1 ). A layer of fluoropolymer resin ( 3 ) was applied to inner walls of the arenas to prevent the bugs from escaping. Arenas were placed simultaneously in a non-ventilated room measuring 4 m long and 2.3 m wide at 24-25° C. A 12:12 hour (L:D) cycle was maintained in the room. Climbup Insect Interceptors, referred to hereafter as “interceptor traps”, were used for comparison. The inventive Insect Trap described herein and shown in FIG. 1 a was made by modifying the prior art device by removing the the central part of the interceptor trap and adding a fabric tape to the exterior surface. The inside surfaces of both trap types were coated with a light layer of fluoropolymer resin (BioQuip products, Rancho Dominguez, Calif., USA) to prevent trapped bed bugs from escaping.
Experiment 1
[0021] Comparative efficacy of the Insect Trap of the Invention for monitoring bed bugs moving away from furniture
[0022] Ten arenas were used to provide 5 replicates for each trap design. Each arena received either the Insect Trap of the invention or Interceptor trap. An arena with one trap type was always placed adjacent to an arena containing the other trap type. A brown cardboard piece (28 cm long and 22 cm wide) was placed in the center of each arena and its edges were sealed with paper tape. Each trap was placed in the center of cardboard and a pine wooden rod (16.5 cm tall, 3.5 cm diameter) was glued to the center of each Interceptor trap or the cardboard to mimic a furniture leg. A 3.7 cm diameter plastic dish was placed on top of the wooden rod to hold bed bugs. Forty bed bugs were confined inside the plastic petri dishes on top of the wooden rods. Each petri dish contained a piece of red paper as harborage ( FIG. 1 ). Six additional bed bug exposed paper harborages were placed along the edges of the floor of each tray arena. At 1 hour after dark cycle, CO 2 was released from a 5 lb cylinder at 100 ml/minute to the room. The plastic cover confining the bugs was removed. Bed bugs would naturally migrate down the wooden rod. The numbers of bed bugs fallen into the traps were counted after 8 hours with the aid of a red light.
Experiment 2
[0023] Comparative efficacy of the Inventive Insect trap for monitoring bed bugs moving toward furniture
[0024] Similar to Experiment 1, 10 arenas were used, providing 5 replicates for each trap type. Each arena received either the Insect Trap of the present invention or Interceptor trap ( FIG. 2 ). An arena with one trap type was always placed adjacent to an arena containing the other trap type. A pine wooden rod was glued to the center of each Interceptor trap or the cardboard to mimic a furniture leg. Forty bed bugs were placed near one corner of the arena and confined for 16 hours using a plastic ring (13.3 cm diameter and 6.4 cm height).
[0025] At 1 hour after dark cycle, CO 2 was released at 100 ml/minute to the room and the plastic ring confining the bugs was removed. Bed bugs orienting to the wooden rod would climb up the trap and fall into the trap. The numbers of bed bugs trapped in the traps were counted after 8 hours with the aid of a red light.
Data Analysis
[0026] The trap count data was subject to analysis of variance using SAS software.
Results and Discussion
[0027] In Experiment 1, the mean numbers of bed bugs trapped in Inventive Insect Trap and Interceptor trap were 22±1 and 6±2, respectively ( FIG. 3 ). Inventive Insect trap caught 3.6 times more bed bugs than the Interceptor trap (F=41.5, df=1, 8; P<0.001).
[0028] In Experiment 2, the mean numbers of bed bugs trapped in the Inventive Insect Trap and Interceptor trap were 23±2 and 19±1, respectively ( FIG. 4 ). There was no significant difference in trap catches (F=2.6, df=1, 8; P=0.15).
[0029] Under natural conditions, bed bugs frequently travel between the floors and beds or other upholstered furniture. Based on the above two experiments, using the Inventive Insect Trap described herein would more likely detect bed bugs coming down the furniture compared to Climbup Insect interceptor. The inventive Insect Trap uses less material than the Climbup Insect Interceptor. In addition, the Insect Trap of the invention does not require thick plastic materials to support furniture legs because there is no need to contact the furniture as Climbup Insect Interceptors does.
[0030] The Insect Trap of the invention can also be placed around an ant nest, an infested article, etc. to intercept insects.
REFERENCES
[0031] 1. Panagiotakopulu, E., and P. C. Buckland. 1999. Cimex lectularius L., The common bed bug from Pharaonic Egypt. Antiquity. 73: 908-911.
2. Usinger, R. L. 1966. Monograph of Cimicidae (Hemiptera-Heteroptera). The Thomas Say Foundation, Vol. VII. Entomological Society of America, College Park, Md.
3. Wang, C., T. Gibb, and G. W. Bennett. 2009a. Evaluation of two least toxic integrated pest management programs for managing bed bugs (Heteroptera: Cimicidae) with discussion of a bed bug intercepting device. Journal of Medical Entomology 46: 566-571.
4. Wang, C., T. J. Gibb., and G. W. Bennett. 2009b. Interceptors assist in bed bug monitoring. Pest Control Technology 37(4): 112, 114.
[0032] 5. Wang, C., W. Tsai, R. Cooper, and J. White. 2011. Effectiveness of bed bug monitors for detecting and trapping bed bugs in apartments. Journal of Economic Entomology 104: 274-278. | An insect trap has a “U” or similar shaped cross-section view, forming a circle or square, with a dark-colored coarse outer surface and a light-colored smooth inner surface. The trap can be placed around an arthropod-infested object such as furniture leg, luggage, food to form a barrier to prevent movement of arthropods between the infested object and its surrounding areas.
The trap can also be placed where arthropods live or forage to monitor their numbers and activities such as at corners of a room, along perimeters of a room, inside a cabinet, inside food storage container, etc. | 0 |
FIELD OF THE INVENTION
The present invention relates in general to computer and telecommunication networks and, more particularly, to file synchronization for fault tolerant telecommunication networks.
BACKGROUND OF THE INVENTION
With the advent of increasingly sophisticated telecommunication services, telecommunication networks are increasingly distributed. For example, rather than having telecommunication services performed by a centralized computer having multiple processors, these telecommunication services are increasingly performed by a distributed network of computers and servers, in which each such computer or server generally contains a single or central processor, such as an Intel Pentium class processor. The advantages of such a distributed network of computers and servers, typically connected to each other via a high speed bus, an ethernet or fiber optic cable, include cost effectiveness and the capability for incremental network growth.
A particular difficulty with such distributed, networked computers concerns fault tolerance, such that if one computer becomes disabled, another computer on the network may immediately take over all the functions previously performed by the disabled computer, with minimal disruption of service. For example, if the primary computer providing telecommunication services (referred to as the active application processor (“active AP”) (also known as a distinguished application processor)) should become disabled (crash), to avoid an interruption of service, a fault tolerant system may provide for a secondary computer (referred to as a standby application processor (“standby AP”)), to immediately assume the performance of all services previously provided by the active AP. In order for the standby AP to immediately come on line with minimal disruption of service, as if no fault or other major event occurred, the standby AP preferably should have access to identical information and be in synchrony with the active AP.
In the prior art, attempts to maintain such synchrony have typically involved copying files by the standby AP from the active AP. Such a copying process is typically very time consuming, involving minutes for copying of gigabit sized files, necessitating an intervening loss or disruption of service. As a consequence, a need remains to reduce any such delay or interruption dramatically, to avoid service interruptions lasting longer than a few seconds.
Other prior art systems, while providing synchrony, typically do not allow such computers to operate autonomously, but only in locked step. Other fault tolerant systems do not provide for a standby mechanism, but merely provide a disk array (raid) for automatic backing up of information stored to a disk. Other systems require additional hardware for redundant clustering computers, and are platform dependent.
As a consequence, a need remains for an apparatus, method and system to provide information synchrony in a fault tolerant network. Such synchrony should occur within a very small time frame, such as seconds, to avoid service interruptions. In addition, such an apparatus, method and system should not require any additional hardware, should be platform independent, and should be application independent, with such fault tolerance occurring transparently to the user and to the application.
SUMMARY OF THE INVENTION
In accordance with the present invention, an apparatus, method and system are provided for file synchronization for a fault tolerant network, in which the fault tolerant network generally includes an active network entity, such as a telecommunication server, and a standby network entity to assume the functionality of the active network entity in the event of a failure of the active network entity. The apparatus, method and system of the present invention provide such information synchrony within a very small time frame, such as seconds, to avoid service interruptions in the event that the active network entity fails and the standby network entity becomes active. In addition, the apparatus, method and system of the present invention do not require any additional hardware, are platform and application independent, with such fault tolerance occurring transparently to the user and to the application.
The method of the present invention begins with accessing a file within the active network entity, such as through a read or write request of any network application. A file access request within the active network entity is generated and transmitted to the standby network entity, which also performs the file access request. The standby network entity then generates and transmits a file access confirmation to the active network entity. The active network entity then determines whether the file access request of the active network entity has a corresponding file access confirmation from the standby network entity. When the file access request has the corresponding file access confirmation, indicating that the files are in synchrony between the active and standby network entities, the active network entity then deletes the file access request and the corresponding file access confirmation from memory. When the file access request does not have the corresponding file access confirmation, however, indicating a lack of synchrony, the active network entity then generates an error message and transfers the file access request to an error log, for subsequent use. Such subsequent use may include generating an alarm condition and transferring the standby network entity to an active status.
As indicated above, this methodology is transparent to and independent of the network application. The methodology is also independent of an operating platform within the active and standby network entities. The various file access requests typically include a read request, a write request, an open request, and a close request, and may be invoked through any type of network application.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating an apparatus and system embodiment of the present invention;
FIG. 2 is an operational flow diagram illustrating the processes occurring within an active AP and a standby AP in accordance with the present invention; and
FIG. 3 is a flow diagram illustrating a method in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is susceptible of embodiment in many different forms, there are shown in the drawings and will be described herein in detail specific embodiments thereof, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.
As mentioned above, a need remains for an apparatus, method and system to provide information synchrony in a fault tolerant network. In accordance with the present invention, an apparatus, method and system provide such information or file synchrony in a fault tolerant network within a very small time frame, such as seconds, to avoid service interruptions. In addition, the apparatus, method and system of the present invention do not require any additional hardware, are platform independent, are application independent, and provide such fault tolerance transparently to the user and to the application.
FIG. 1 is a block diagram illustrating apparatus 20 and system 10 embodiments of the present invention. Each apparatus 20 may be considered a network entity, such as service control point, a service node, or another type of telecommunication server, with the system 10 including a plurality of such apparatuses 20 coupled via a communication link 15 , such as an ethernet or any other link of any communication medium (such as T1/E1, fiber optic cable, coaxial cable, etc.). Referring to FIG. 1, each apparatus 20 (designated as 20 A and 20 S ) includes a processor (CPU) 30 , a network interface (NIC) 35 , a first memory 40 (such as RAM), and a second, longer term memory 50 (such as a magnetic hard drive, optical storage device, or any other type of data storage device). Each apparatus 20 , at any given time, may have an operating state referred to as active ( 20 A ) or standby ( 20 S ), and in the preferred embodiment, each apparatus 20 A and 20 S is a corresponding active AP or standby AP.
The apparatuses 20 A and 20 S are connected to each other (and potentially to other apparatuses 20 ) via a communication link 15 , such as an ethernet or other network transmission medium, for communication with each other via each of their corresponding network interfaces 35 , to form a system 10 in accordance with the present invention. Within or coupled to each apparatus 20 , the second, longer term memory 50 , such as a magnetic hard drive, is utilized for data or other file storage. In accordance with the present invention, data or other file access (as discussed in greater detail below) is synchronized between the active AP (such as apparatus 20 A ) and the standby AP (such as apparatus 20 S ). Within each apparatus 20 , the first memory 40 is used, in the preferred embodiment, to store program instructions as discussed below. The processor 30 has bi-directional access to the second memory 50 , such as for opening, reading from, writing to, and closing files stored in the second memory 50 .
Continuing to refer to FIG. 1, each processor (CPU) 30 may include a single integrated circuit (IC), or may include a plurality of integrated circuits or other components, connected, arranged or grouped together, such as microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), associated memory (such as RAM and ROM), and other ICs and components. As a consequence, as used herein, the term processor should be understood to equivalently mean and include a single processor, or arrangement of processors, microprocessors, controllers or some other grouping of integrated circuits which perform the functions discussed above and also discussed in detail below with reference to FIGS. 2 and 3, with associated memory, such as microprocessor memory or additional RAM, ROM, EPROM or E 2 PROM. The methodology of the invention, as discussed below with reference to FIGS. 2 and 3, may be programmed and stored, in the processor 30 with its associated memory (such as first memory 40 ) and other equivalent components, as a set of program instructions for subsequent execution when the processor 30 is operative (i.e., powered on and functioning).
As discussed in greater detail below, whenever an application within an active AP, such as apparatus 20 A , accesses a file within the second memory 50 A , that file access is duplicated, in real time, within the standby AP (apparatus 20 S ) and its corresponding second memory 50 S . Utilizing “FSYNC” processes within each processor 30 A and 30 S , whenever a file access occurs in the active apparatus 20 A , a corresponding file access request is transmitted by the active processor 30 A (via the network interface 35 A , communication link 15 and network interface 35 S ) to the standby processor 30 S . The standby processor 30 S then processes the file access request, and returns a confirmation (also via the communication link 15 and the corresponding network interfaces 35 ) to the active processor 30 A . The active processor 30 A , through the FSYNC processes, monitors that every file access request (within the active AP) has a corresponding confirmation from the standby AP. As a consequence, the methodology of the present invention insures that the standby AP has virtually immediate access to all current information stored within the active AP.
FIG. 2 is an overall, operational flow diagram illustrating a methodology of the present invention, as exemplified by the processes occurring in an active AP 100 and a standby AP 200 in accordance with the present invention. As illustrated in FIG. 2, there are a collection of file synchronization processes referred to as “FSYNC”, which pertain to the synchronization of selected files (stored in second memory 50 ) from the active AP 100 to the standby AP 200 . As illustrated in FIG. 2, these file synchronization (FSYNC) processes are the FSYNC auditor 105 , the FSYNC daemon 110 , and the FSYNC file access process 115 (also referred to as FSYNC (ftsp) file access, wherein “ftsp” refers to fault tolerant system processes). These FSYNC processes are identical in the active AP 100 and the standby AP 200 , and are differentiated with subscripts, such that the subscript “A” designates the active processes occurring within the active AP 100 , while the subscript “B” designates the standby processes occurring within the standby AP, at any given time. It should be noted that at any particular time, a given apparatus 20 (such as a AP or other computer) may transition from an active status to an inactive or out-of-service AP, or from an active to a standby AP, or from a standby to an active AP. As a consequence, each process may be contained within both active and standby APs, although different processes may be functioning at any given time.
Continuing to refer to FIG. 2, the file synchronization methodology of the present invention occurs when any application (or process) 120 accesses information, data or other files (individually and collectively referred to herein as “files”) located in memory 130 , such as the second memory 50 illustrated in FIG. 1 . Such a memory 130 , for example, may be a magnetic hard drive, a magnetic tape drive, or an optical storage medium. As illustrated in FIG. 2, such access of the memory 130 by the application (or process) 120 is illustrated as access 140 , which may be a request to open a file, to read from a file, to write to a file, or to close a file, with such a file stored in the memory 130 . Any type of application 120 may be involved, and the file synchronization methodology of the present invention is completely transparent to and independent of any given application 120 and any given platform of the apparatus 20 (AP).
In the preferred embodiment, whenever such an application 120 occurs which involves access to memory 130 , a library of functions are called or invoked, referred to as the FSYNC file access functions 115 . As a consequence, when a file is accessed ( 140 ) by an application (or process) 120 , the target file is accessed via a FSYNC file access function, and the result of the file access ( 141 ) is returned to the application (or process) 120 .
As the application (or process) 120 requests access to a file in memory 130 , it instantiates a new object of the class or library FSYNC 115 , such as FSYNC_Disk_IO ( ). As the constructor FSYNC_Disk_IO( ) is executed, the FSYNC daemon 110 receives a signal or interrupt ( 142 ), and the request for file access is also registered ( 143 ) in a request queue 150 . The FSYNC daemon 110 , now interrupted, examines ( 144 ) the request queue 150 , and sends ( 145 ) the request for file access (that was in the request queue 150 ) to the application processor node manager (or management) (APNM) 155 , which is store and forward software to transmit information to other computers or servers on a network or other system (via the network interfaces 35 and the communication link 15 ). The APNM 155 A then transmits the file access request ( 146 ) to the standby AP 200 , which in turn is received by the APNM 155 S of the standby AP.
The APNM 155 S of the standby AP 200 then transfers ( 147 ) this remote request for file access to the FSYNC daemon 110 S operating within the processor 30 S on the standby AP 200 . The FSYNC daemon 110 S then performs ( 148 ) the request for file access, such as opening or writing to a particular file stored in memory 130 S (such as second memory 50 S ) and receives ( 149 ) a return value, such as num_bytes_written. The FSYNC daemon 110 S then transfers this return result as a confirmation ( 151 ) to the APNM 155 S , which in turn transmits ( 152 ) the confirmation to the active AP 100 (also via the network interfaces 35 and the communication link 15 ). The APNM 155 A of the active AP 100 then transfers ( 153 ) the confirmation to the FSYNC daemon 110 A which registers ( 154 ) the received confirmation in the confirmation queue 160 .
The FSYNC Auditor 105 A regularly monitors the operational status of the FSYNC daemon 110 A , which regularly transmits ( 156 ) an announcement or “heartbeat” to the FSYNC Auditor 105 A . The FSYNC Auditor 105 A also regularly or periodically monitors the file synchronization process. The FSYNC Auditor 105 A reads ( 157 ) the confirmation queue 160 and reads ( 158 ) the request queue 150 . The FSYNC Auditor 105 A then compares every confirmation with a corresponding request, and if they are both valid, they may be deleted from their respective queues 150 and 160 . In the event a matching confirmation from the standby AP 200 cannot be matched to a corresponding request in the request queue 150 , the FSYNC Auditor 105 A transfers ( 159 ) the request from the request queue into the error log 170 for a later audit or alarm condition.
As illustrated in FIG. 2, the various processes of the present invention provide that every file access in the active AP is matched by a file access in the standby AP, thereby insuring that the standby AP has up-to-date information at all times. In addition, in the event that the active AP is not transmitting such requests to the standby AP, such that no confirmations are then received by the active AP, any missing information in the standby AP may be recovered from the error log 170 .
FIG. 3 is a flow diagram illustrating the method in accordance with the present invention. The method begins, start step 205 , with a process in the active AP requesting access to a file. The request for file access is then registered in the request queue, and the FSYNC daemon process in invoked, such as through an interrupt signal, step 210 . Next, in step 212 , the FSYNC daemon sends the file access request to APNM, and the APNM transmits the request for file access to the standby AP, step 214 . The APNM in the standby AP receives the file access request, step 216 , and sends the request for file access to the FSYNC daemon in the standby AP, step 218 .
Continuing to refer to FIG. 3, the FSYNC daemon in the standby AP invokes the FSYNC ftsp file access function, step 220 . The target file is accessed, and a return result value is returned to the FSYNC daemon in the standby AP, step 222 . The FSYNC daemon then generates a confirmation from the return result value, step 224 , and transmits the confirmation to the active AP via the APNM of the standby AP, step 226 . The APNM of the active AP then receives the confirmation, step 228 , and transfers the confirmation to the FSYNC daemon. The FSYNC daemon sends the confirmation to the confirmation queue, step 230 . Periodically, the FSYNC Auditor reads the request queue and the confirmation queue, step 232 , and compares each confirmation with each request, step 234 . When there is a valid confirmation for each request, step 236 , the corresponding confirmation and request may be deleted from their respective queues, step 238 , and this portion of the method may end, return step 242 . When in step 236 a valid confirmation cannot be paired with a corresponding request, the file access request is transmitted to the error log, step 240 , followed by a possible alarm condition, and the method may also end, return step 242 .
In accordance with the present invention for file synchronization, an exemplary program in the C++ language is illustrated below, for utilizing C++ derived classes in a manner that is transparent to and independent of any particular application or process within the active and standby APs. Using the Object-Oriented Programming capabilities of the C++ language, new C++ classes are derived with inheritance from the original base classes. The new classes will contain methods for synchronization in accordance with the present invention. For example, an ftsp class which originally contains iofstream will now be derived to fsync_iofstream. The latter will guarantee that a file write is replicated both in the active and standby APs. An AP daemon may be utilized to insure which AP is active, standby, or out-of-service, at any given time.
The following example shows how a new derived class syn_Disk_IO is derived from the ftsp class Disk_IO.
/*
*
@(#) Disk_IO.H 2.1.1.2/sunsable/nsps/sdb/nsps/2nsps
/util/Shared/src/s.Disk_IO.H
*
Disk_IO.H 2.1.1.2 20 Nov 1996 16:47:09
*/
#ident “@(#) Disk_IO.H 2.1.1.2/sunsable/nsps/sdb/nsps
/2nsps/util/Shared/src/s.Disk_IO.H”
/*
*
NAME:
Disk_IO
*
WHAT:
*
This is the class that support disk reads, writes, and
*
seeks. The constructor will open the specified file,
*
and the destructor will close the file. In the case
*
where a file size is specified, these routines will
*
manage the file size to not exceed the specified number
*
of blocks.
*/
class Disk_IO
{
public:
Disk_IO( );
DISK_IO(char *file_name);
Disk_IO(char *file_name, int max_size, int block_size =
DEV_BSIZE);
˜Disk_IO( );
int dread(char *file_name, int);
int dwrite(char file_name, int);
int seek(long);
public:
static Trace_tool NS_UTIL_DISKIO;
// Trace object for
debugging
int
io_error;
// upon encountering
errors, errno is
stored here
Boolean
bad_obj;
// Keeps track of object
being usable/not
int
first_block;
// First data block of the
file
int
fp;
// UNIX file descriptor
value
int
highest_write;
// Highest written
location so far
int
bsize;
// # bytes in each block
int
current_read;
// Block to be read
next
int
current_write;
// Block to be written
next
char
fname[DISK_MAX_NAME];
// Name of the file
};
The new derived Class with synchronization:
class fsync_Disk_IO( ) : public Disk_IO
{
public:
fsync_Disk_IO( )
// FSYNC constructor
fsync_Disk_IO(char *file_name) ;// FSYNC constructor
fsync_Disk_IO(char *file_name, int max_size, int
block_size=DEV_BSIZE);
// FSYNC constructor
// This constructor will cause all file accesses to
wait for completion of FSYNC
fsync_Disk_IO(char *file_name, int max_size, int
Block_size=DEV_BSIZE, bool wait_for_fsync);
-Disk_IO( ) ;
// new FSYNC destructor
//new member functions with FSYNC
int dwrite(char *Queue, int num_bytes);
int dread(char *Queue, int num_bytes);
int seek(long offset);
}
As illustrated above, in accordance with the present invention, every file access in an active AP is effectively duplicated, in real time, in a standby AP. As a consequence, in the event that the standby AP is required to assume the functionality of the active AP and transition to an active mode, the standby AP already has immediate access to virtually all current information utilized by the (formerly) active AP. As a further consequence, in the event of such transitions in a fault tolerant network, service interruption is minimized.
Numerous other advantages of the present invention may be apparent. The apparatus, method and system of the present invention provide information synchrony in a fault tolerant network, and provide such information or file synchrony in a fault tolerant network within a very small time frame, such as seconds, to avoid service interruptions. In addition, the apparatus, method and system of the present invention do not require any additional hardware, are platform independent, are application independent, and provide such fault tolerance transparently to the user and to the application.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the novel concept of the invention. It is to be understood that no limitation with respect to the specific methods and apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims. | An apparatus, method and system are provided for file synchronization for a fault tolerant network, and are both application and platform independent. The fault tolerant network generally includes an active network entity, such as a telecommunication server, and a standby network entity to assume the functionality of the active network entity in the event of a failure of the active network entity. The method of the present invention includes accessing a file within the active network entity, such as through a read or write request of any network application. A file access request within the active network entity is generated and transmitted to the standby network entity, which also performs the file access request. The standby network entity then generates and transmits a file access confirmation to the active network entity. The active network entity then determines whether the file access request of the active network entity has a corresponding file access confirmation from the standby network entity. When the file access request has the corresponding file access confirmation, indicating that the files are in synchrony between the active and standby network entities, the active network entity then deletes the file access request and the corresponding file access confirmation from memory; but when the file access request does not have the corresponding file access confirmation, indicating a lack of synchrony, the active network entity then generates an error message and transfers the file access request to an error log, for subsequent use. | 6 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a method for the generative production of components, particularly for the production of components of turbomachines in which the component is constructed in layers on a substrate or on a previously produced part of the component, with construction in layers occurring by melting powder material in layers with a high-energy beam and solidification of the melt.
Prior Art
Generative production methods for producing a component, such as, for example, stereolithographic methods, selective laser melting, selective laser sintering, electron beam melting, or laser deposition welding, are used in the industry for so-called rapid tooling and rapid prototyping or also for the mass production of products within the scope of rapid manufacturing. In particular, such methods can also be used for the production of turbine parts, particularly parts for aircraft engines, in which such generative production methods are advantageous on account of the material used, for example. An example of this is found in DE 10 2010 050 531 A1.
Moreover, owing to the conditions of use and the requisite properties, it is advantageous in the case of components for turbomachines to use single-crystalline or directionally solidified components in order to specifically exploit the anisotropy of properties, such as, for example, different mechanical properties with respect to crystal orientation. Thus, for example, it is known how to produce turbine blades or vanes from single-crystalline or directionally solidified nickel-based superalloys. Here, single crystalline means that the component is formed from a single crystal, so that there are no grain boundaries. Although many crystal grains are present in the component in the case of directionally solidified components, the latter are nearly identical with respect to their crystal orientation and, in particular, they are oriented in a preferred direction so as to exploit the special properties along the preferred direction.
Because the production of such components is very complicated, an attempt has already been made to produce such components by generative methods as well and this can be advantageous in the case of small-scale serial production, for example. Examples of this are described in EP 0 861 927 A1, EP 0 892 090 A1, WO 2004/028786 A1, WO 2013/029959 A1, or DE 10 2009 051 479 A1.
However, there continues to be a need for improving the known methods in order to improve the quality of the single-crystalline or directionally solidified components produced and to be able to use the method reproducibly on an industrial scale. In particular, a method that enables the targeted control of the construction in layers is needed in order to be able to adjust the anisotropy properties of the produced component in a defined manner.
BRIEF SUMMARY OF THE INVENTION
Object of the Invention
The object of the present invention is therefore to provide a generative method for producing, in particular, single-crystalline or directionally solidified components, said method affording reproducible and reliable results of high quality in regard to the targeted solidification, in particular the single-crystal properties of single-crystalline solidified components or the uniform orientation of the crystallites in directionally solidified components. At the same time, it should be possible to apply the method in a simple and effective manner.
Technical Solution
This object is achieved by a method of the present invention. Advantageous embodiments are set forth in the claims.
The present invention derives from the realization that an improvement in terms of the above-mentioned object being posed can be achieved in that, in a generative production method involving melting of powder material in layers by a high-energy beam and solidification of the powder melt, the high-energy beam is chosen such that it has a cross section that is altered relative to a circular cross section in the area of its impingement on the powder material. Alternatively or additionally, the beam energy can be distributed non-uniformly, in particular asymmetrically or eccentrically, over the beam cross section of the high-energy beam in the area of its impingement on the powder material. According to another embodiment, which can be implemented alternatively or additionally in turn, the powder material can be irradiated, after melting has occurred, by a high-energy beam at least one second time at an interval in time after the melting, said high-energy beam bringing about an altered energy input into the powder material in comparison to the melting. All of these measures enable a targeted solidification of the melted powder material in a simple but simultaneous manner. In particular, it is possible to achieve an epitaxial growth of the material deposited in layers in order to thereby produce single-crystalline or directionally solidified components. Of course, the method parameters can also be chosen such that a globulitic solidification is achieved. Depending on the case of application, the method parameters can be adjusted such that a desired solidification structure will be obtained.
The two or multiple irradiations of the same powder material with different irradiation energies at intervals in time can be accomplished by irradiation of the powder material or the component with two or more high-energy beams, which can be generated independently of one another.
In this process, the irradiation with a second beam or with additional high-energy beams can occur at times when the powder material that has been melted by the first irradiation has not yet solidified and, in particular, has not yet fully solidified.
Similarly to the case of energy input into the melted powder material by using a plurality of high-energy beams after melting has occurred, the melting of the powder material can also be brought about by a plurality of high-energy beams, which, in particular, act successively on the powder material at intervals in time. Moreover, it is also possible to preheat the powder material with high-energy beams as well as with other heating devices.
The high-energy beams can be laser or electron beams.
In the proposed invention, the generative production of the component by melting of powder material in layers can be accomplished in that the high-energy beam or beams are directed along movement tracks over the powder material, which is arranged in a powder bed.
The movement tracks along which the high-energy beams are directed can overlap one another, in particular, in order to accomplish multiple irradiation of the same powder material or the already melted and/or re-solidified powder material even with a single high-energy beam. Of course, the tracks of movement can also be chosen such that the movement tracks, depending on the respective beam cross section, do not overlap one another in the area of impingement on the powder material.
Furthermore, the track separation can be suitably chosen in order to adjust the desired temperature distribution in the powder material or the melt and the already solidified component.
Overall, a computer-assisted simulation of the energy input and the local temperature distribution and/or the temperature distribution over time in the powder material and/or in the already produced component and/or in the melt can be generated so as, by means of the computer-assisted simulation, to be able to adjust the method parameters such that the desired solidification structure, such as, for example, a globulitic structure or, in particular, a single-crystalline or directional solidification of the component is achieved. The proposed method therefore offers the possibility of targeted control of the solidification of the deposited material layers and thus the targeted exploitation of anisotropy effects of the material through defined solidification.
To this end, the phase state of the powder material and/or the solidification direction and/or the solidification rate of the melted powder material can be determined by the computer-assisted simulation, so that, through variation of one or more parameters of the irradiation with the high-energy beam, it is possible to adjust the desired deposition. Thus, the parameters of the high-energy beams can be adjusted or varied in terms of the power of the high-energy beam or beams, the number of high-energy beams, the shape of the beam cross section of the beam or beams, the non-uniform, particularly asymmetric or eccentric energy distribution over the beam cross section of the high-energy beam or beams, the time interval of a second irradiation or of additional irradiations of the powder material, the geometry of the tracks of the high-energy beams, and the track separation of the tracks of movement of the high-energy beams.
In particular, it is possible in this way to achieve an epitaxial growth of material during deposition in layers. In addition, it is possible to adjust various orientations of the solidified crystallites, so that, for example, different crystal orientations can be adjusted in differently deposited layers. Thus, it is possible to adjust a different crystal orientation in each deposited layer or after a plurality of identical layers. In this way, anisotropy effects can be utilized even in globulitically solidified structures if, in the individual layers or plurality of layers, separated and differently oriented crystallites are present, but are still oriented in a defined manner.
Accordingly, computer-assisted simulation enables the parameters for the irradiation to be chosen in such a way the solidification conditions are such that single-crystalline or directionally solidified components can be produced.
BRIEF DESCRIPTION OF THE FIGURES
The appended drawings show in a purely schematic manner:
FIG. 1 is a schematic illustration of a device for the generative production of components as exemplified by selective laser melting;
FIG. 2 is a partial sectional view through an already produced component and the powder bed with the melted and solidified area; and
FIG. 3 is an illustration of the tracks of movement and the beam cross section of laser beams during implementation of the method according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
Further advantages, characteristics, and features of the present invention will be elucidated in the following detailed description of an exemplary embodiment, with the invention not being limited to this exemplary embodiment.
FIG. 1 shows a purely schematic illustration of an apparatus 1 , such as may be used, for example, for selective laser melting for the generative production of a component. The apparatus 1 comprises a lift table 2 , on the platform of which a semi-finished product 3 is arranged, on which a material is deposited in layers in order to produce a three-dimensional component. To this end, powder 10 , which is situated above a lift table 9 in a powder hopper, is pushed layer by layer over the semi-finished product 3 by means of a slider 8 and subsequently bonded to the already present semi-finished product 3 by melting brought about by the laser beam 13 of a laser 4 . The bonding of the powder material in a powder layer with the semi-finished product 3 is brought about by the laser 4 regardless of the desired contour of the component being fabricated, so that any desired three-dimensional shapes can be produced. Accordingly, the laser beam 13 is directed over the powder bed 12 in order to melt powder material, corresponding to the contour of the three-dimensional component in the sectional plane corresponding to the produced sectional plane, by way of different points of impingement on the powder bed and to bond them with the already produced part of a component or an initially already prepared substrate. In the process, the laser beam 13 can be directed by a suitable deflecting device over the surface of the powder bed 12 and/or the powder bed could be moved relative to the laser beam 13 .
In order to prevent undesired reactions with the surrounding atmosphere during melting or sintering, the process can take place in an enclosed space, which is provided by a housing 11 of the apparatus 1 , and, in addition, an inert gas atmosphere can be provided in order to prevent, for example, oxidation of the powder material and the like during deposition. Nitrogen, which is supplied via a gas source that is not illustrated, may be used as inert gas, for example.
In place of the inert gas, a different process gas could also be used, if, for example, a reactive deposition of the powder material is desired.
Moreover, other types of beams are also conceivable, such as, for example, electron beams or other particle beams or light beams that are used in stereolithography.
For adjustment of the desired temperatures in the produced component 3 and/or in the powder bed 12 , an electric resistance heater with a resistance heating control 5 and an electric heating wire 6 is provided in the lift table, so that the powder bed 12 and the component 3 can be brought to a desired temperature by appropriate heating from below and/or a desired temperature gradient, in particular one in relation to the just processed layer at the surface of the powder bed, can be adjusted. In a similar manner, heating with a heating device from the top side of the powder bed 12 and the already produced component 3 is provided and, in the exemplary embodiment shown, said heating device is constituted by an induction heater with an induction coil 14 and an induction heating control 15 . In this process, the induction coil 14 surrounds the laser beam 13 and, as needed, can be moved parallel to the surface of the powder bed 12 depending on the laser beam 13 .
In place of the illustrated induction heating, any other type of heating that enables a heating of the powder bed 12 and the already produced component 3 from the top side can be provided, such as, for example, radiant heating devices, such as infrared emitters and the like. In the same way, the resistance heater 5 , 6 can also be replaced by other suitable types of heaters that enable a heating of the powder bed 12 and the already produced component 3 from below. Moreover, other heating devices can be provided surrounding the already produced component 3 and/or the powder bed 12 in order to make possible lateral heating of the powder bed 12 and/or the already produced component 3 .
Besides heating devices, cooling devices or combined heating/cooling devices can also be provided in order to be able to perform, in addition to a heating of the already produced component 3 and the powder bed 12 , also a targeted cooling so as to be able to adjust and influence in a targeted manner the temperature balance in the powder bed 12 and/or the produced component 3 , particularly with respect to the powder layer melted by the laser beam 13 and the solidification front at the melted powder material.
FIG. 2 shows the situation in the area of an additional layer in the area of the solidification front that is to be applied directly to the already produced component 3 .
In FIG. 2 , a part of the already produced component 3 can be seen as well as a part of the powder bed 12 with the powder particles prior to melting. Next to the powder particles of the powder bed 12 is the melt 16 of the already melted powder material after the laser beam 13 has impinged on the powder material of the powder bed 12 . Because the laser beam 13 is directed further over the powder bed 12 to produce the contour in the corresponding layer of the component, the melt 16 cools again after irradiation by the laser beam 13 , so that solidification of the melted powder material ensues. In the process, regardless of the temperature distribution in the melt 16 and the surrounding areas, a solidification front 17 is formed, which progresses in the direction of the melt 16 and in the direction of the adjusted and directional temperature gradient and at which the melted material is transformed into solidified material.
In accordance with the invention, the energy is input through the laser beam or beams 13 and the heating devices 5 , 6 , 14 , 15 so that the desired solidification structure and crystal orientation are achieved. By means of a slow rate of solidification, that is, slow progression of the solidification front 17 with a simultaneously high temperature gradient at the solidification front, a planar single-crystalline solidification of the melted powder material or an epitaxial growth of the latter occurs on the already produced component 3 . This is schematically highlighted in FIG. 2 by illustration of a uniform lattice 18 , which represents the uniform crystal structure of the already produced component 3 and the solidified melt 16 at the solidification front 17 .
FIG. 3 shows, in a schematic illustration, the movement of one or more laser beams 13 over the powder bed 12 . As illustrated in FIG. 3 , the laser beam moves, for example, in the form of a meandering movement track 20 over the powder material present in the powder bed 12 . In the case of the movement track 20 , the laser beam 13 moves in the direction of the arrow 21 along the movement track 20 .
The beam cross section 19 in the area of the impingement face of the laser beam on the powder material is not circular in the exemplary embodiments shown, but rather has a rounded wedge shape. At the same time, the beam energy distribution is non-uniform over the beam cross section and is indeed such that, in the area of the thicker end of the wedge-shaped beam cross section, there is a higher beam energy per unit area than in the pointed end of the wedge-shaped beam cross section. This means that the beam cross section 19 has a greater melting area 22 in terms of its diameter and a smaller post-heating area 23 in terms of its diameter. As a result, the beam energy is distributed non-uniformly over the beam cross section 19 and is indeed such that, in the melting area 22 , there is a higher beam energy than in the post-heating area 23 .
The movement track 20 of the laser beam 13 is then shaped such that, in the case of the meandering track, the parallel track segments are separated by a distance D that is smaller than the longitudinal extension of the beam cross section 19 , so that the beam cross section 19 at least partially overlaps the already irradiated area. In particular, the laser beam 13 is directed along the movement track 20 such that the post-heating area 23 of the beam cross section 19 overlaps during further movement of the laser beam 13 in the area in which the powder material had previously been melted by the melting area 22 of the beam cross section 19 . In this way, it is possible to use a single laser beam 13 to bring about the melting and the requisite post-heating so as to achieve a low rate of solidification and/or a high temperature gradient in a simple manner.
Alternatively or additionally, it is possible to direct a second laser beam in temporal succession on the same movement track 20 and/or simultaneously and/or at a time delay on a second movement track 20 ′, which is spatially offset with respect the first movement track 20 , in order to adjust, in conjunction with the heating devices 5 , 6 , 14 , 15 , the desired temperature distribution in the area of the powder bed 12 , the melt 16 , the solidification front 17 , and the already produced component 3 , so that an epitaxial growth of the solidifying powder material on the already produced component 3 or on a provided substrate occurs.
The measures described make it possible to control the temperature conditions in the melt and surroundings and thus the magnitude and direction of the temperature gradient at the solidification front as well as its rate and direction during passage through the melt and hence the solidification direction and the orientation of the solidified crystallite or crystallites.
In place of a completely epitaxial growth to obtain a single-crystalline component, it is possible, depending on the chosen method parameters, also to achieve a directionally solidified growth so as to create a component with a plurality of crystal grains, which are oriented along a preferred direction. In addition, globulitically solidified structures can be produced.
Although the present invention has been described in detail on the basis of exemplary embodiments, it is understandable to the person skilled in the art that the invention is not limited to these exemplary embodiments, but rather alterations are possible in such a manner that individual features can be omitted or other types of combinations of features can be implemented, as long as there is no departure from the protective scope of the appended claims. The present disclosure includes all combinations of the individual features presented. | The present invention relates to a method for the generative production of components, particularly of single-crystalline or directionally-solidified components, particularly for the production of components for turbomachines, in which the component is constructed in layers on a substrate or a previously produced part of the component ( 3 ), wherein a construction in layers takes place by melting of powder material in layers with a high-energy beam ( 14 ) and solidification of the powder melt ( 16 ) takes place, wherein the high-energy beam has a beam cross section ( 19 ) in the area of its impingement on the powder material that is altered in comparison to a circular or other symmetrical cross section and/or the beam energy is distributed non-uniformly, in particular asymmetrically or eccentrically, over the beam section. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 12/996,195, filed on Dec. 13, 2010, which is a continuation-in-part of PCT/ES2009/070261 filed Jun. 27, 2009 which claims benefit from GB Application No. 0811815.0, filed Jun. 27, 2008, now GB Patent No. 2460096 granted Nov. 18, 2009.
Applicant Rasheed, Wajid U.S. application Ser. No. 12/966,195 Country USA Priority WO 2009/PCT 156552 A1 and GB0811815.0 (27 Jun. 2008) granted GB2465504
FIELD OF THE INVENTION
This invention relates to an integrated expansion and sensing tool that is capable of enlarging and measuring borehole and tubular diameters, especially wellbores in the oil and gas industry. The tool finds particular use as an underreamer capable of sensing vibration, but can also be configured with other sensors such as callipers to measure wellbore diameter.
When constructing an exploration or production well, numerous downhole operations are conducted to drill and measure a borehole so that it meets the desired well-plan. Drilling itself may utilise a reamer to ensure that the hole diameter that has been drilled by the bit is maintained within the given tolerance. The hole diameters drilled by the bit and perfected by the reamer are substantially the same as the maximum cutting diameter of a reamer, which is fixed and is substantially the same as the bit diameter. This maximum cutting diameter is defined by the pass-through diameter of any restriction in the borehole above the operating location.
In contrast to a reamer, an underreamer is used to enlarge a borehole beyond its original drilled size. Enlargement is typically done below a restriction in the borehole, and the cutting diameter of an underreamer is always greater than that of the pass-through diameter of the restriction. Additionally, an underreamer is provided with activation and deactivation modes and mechanisms for extending and retracting cutting elements to ensure effective underreaming once it has passed below the restriction.
Measurement may involve the acquisition and communication to surface of various types of wellbore data such as drilling dynamics, resistivity, porosity, permeability, azimuth, inclination and borehole diameter or rugosity, formation dips or bedding angles.
Measurement itself occurs in two modes, either wireline or logging-while-drilling. Wireline is by far the most common measurement technique and is performed as a separate and consecutive activity to drilling involving the conveyance of measurement tools on a wire or cable. Wireline calipers use a plurality of fingers to take borehole diameter measurements. However, wireline calipers can only take measurements in an axial direction. Due to this limitation, they can only be used after drilling otherwise the rotational and impact forces of drilling would cause them to break. Hence a separate caliper run is required after drilling to measure borehole diameter.
Logging-while-drilling or measurement-while-drilling tools may acquire various data from the wellbore. For drilling dynamics, measurement-while-drilling are the preferred means of acquiring drilling data such as vibration. Acoustic calipers may be incorporated within logging tools. As they can be rotated, acoustic calipers may be used while drilling to acquire measurement data. However, almost all logging tools are configured as complete systems and are only available at very high cost. Further they also suffer from limitations in applications with slide drilling, where a downhole motor rotates the bit and drags the drillstring and bottom-hole assembly, or BHA. Or in Rotary steerable applications where they are configured near to the bit. Therefore, the location of the sensor is within the BHA below the underreamer. It can only give readings after the section has been underreamed.
Presently, borehole measurements do not provide for drilling dynamics data specifically acting on the underreamer. It is routine for drilling dynamics data to be taken below the underreamer but this does not in any way characterize the forces acting on the underreamer.
Further, wellbore diameter measurements are often not taken and the time-lag associated with the separated operations of enlargement and measurement leads to uncertainty and unnecessary cost. In the case of underreaming, wellbore measurements are taken after underreaming, which means a separate caliper run and at times further corrective runs to attain the desired wellbore diameter.
Further, as drilling has already been completed and no vibration data was acquired directly above the underreamer, there are no means of measuring the actual forces acting on the underreamer or its behaviour in real-time. The present invention is differentiated in this aspect as it provides real-time drilling dynamics data of the underreaming operation which would enable a driller to identify a vibration mode and change drilling conditions to eliminate the vibration. This would reduce harmful vibrations which are a major cause of downhole tool failures as well as the lower rates of penetration related to underreaming in medium to hard formations or interbedded formations.
BACKGROUND OF THE INVENTION
Oil and gas accumulations are found at depth in different geological basins worldwide. Exploration and production of such accumulations rely on the construction of a well according to a well plan.
Various well types exist and are defined according to usage such as wildcats or those used in exploration; delineation; and production and injection. Variations in well profile exist also according to vertical, slant, directional and horizontal trajectories. Each differs according to the oil company's objectives and the challenges that a given basin presents from the surface of the earth or the ocean to the hydrocarbon reservoir at a given underground depth.
Engineering challenges are related to the location of the well-site such as onshore or offshore, seawater depths, formation pressures and temperature gradients, formation stresses and movements and reservoir types such as carbonate or sandstone. To overcome these challenges, a highly detailed well plan is developed which contains the well objective, coordinates, legal, geological, technical, well engineering and drilling data and calculations.
The data is used to plot a well profile using precise bearings which is designed in consecutive telescopic sections-surface, intermediate and reservoir. To deliver the well objective and maintain the integrity of well over its lifecycle, a given wellbore with multiple sections and diameters is drilled from surface. Although there are many variants, a simple vertical well design could include a surface or top-hole diameter of 17½″ (445 mm), intermediate sections of 13⅝″ (360 mm) and 9⅝″ (245 mm) narrowing down to the bottom-hole diameter of 8½″ (216 mm) in the reservoir section.
Each consecutive section is ‘cased’ with the specified diameter and a number of metal tubes placed into the wellbore according to the length of the section. Each must be connected to each other after which they are cemented into the appropriately sized hole with a given tolerance. In this way, a well is constructed in staged sections, each section dependent on the completion of the previous section until the well is isolated from the formation along the entire distance from surface to the reservoir.
Scarcity of oil and gas is driving oil and gas companies to explore and develop reserves in more challenging basins such as those in water-depths exceeding 6,000 ft (1830 m) or below massive salt sections. These wells have highly complex directional trajectories with casing designs including 6 or more well sections. Known in the art as ‘designer’ or ‘close tolerance casing’ wells, these wells have narrow casing diameters with tight tolerances and have created a need to enlarge the wellbore to avoid very narrow diameter reservoir sections and lower production rates.
Therefore, the bottom-hole assemblies that are needed to drill these wells routinely include devices to underream the well-bore below a given casing diameter or other restriction. In this way, underreamed hole size has become an integral part of well construction and there is now an increased dependence on underreaming to meet planned wellbore diameters.
To those skilled in the art, it is known that underreaming activities generate uncertainty as to drilling dynamics and enlarged wellbore diameter. This is because the prior art does not provide for drilling dynamics data acting on the underreamer. If any drilling data is provided, it is in the pilot hole or where drilling has already taken place. Consequently, the lack of underreaming dynamics and vibration data results in a limited understanding of the actual loads and forces acting on the underreamer in real-time.
The present invention is differentiated in this aspect as it provides real-time drilling dynamics data of the underreaming operation which would enable a driller to identify a vibration mode and change drilling conditions to eliminate the vibration. This would reduce harmful vibrations which are a major cause of downhole tool failures as well as the lower rates of penetration related to underreaming in medium to hard formations or interbedded formations.
The data maybe transmitted in real-time by means of data transfer (mud pulse telemetry, fibre-optic or other) or maybe stored in memory and downloaded at a later time. The present invention would make underreamed drilling data available and optimize underreaming operations thereby reducing failures and improving drilling efficiency.
The present invention provides for a novel approach that measures underreaming drilling dynamics and pilot hole drilling dynamics considering the two as separate but inter-related with each subject to different levels of vibration, weight, torque, bending moments, accelerations etc. Typically, an underreaming run has no means of investigating drilling dynamics at the underreamer and therefore corrective actions are limited to reducing the rate of penetration, reducing the rotary speed, reducing the weight on bit.
Drilling vibration occurs in two modes which are classed as resonant i.e. torsional, axial, lateral and non-resonant vibration, i.e. eccentric, sudden modes releasing stored torque known as backward rotation and whirl. Each mode maybe defined separately but in reality all modes are experienced during drilling, the severity of each level depends on the drilling BHA design, drilling dynamics and geological formations. Axial vibrations are often manifested as a stick-slip condition where weight applied at surface causes compression of the drill-string. Due to the geometry of the wellbore and bending moments, the weight is concentrated at the widest diameters of the drill-string which is the underreamer, stabilizers, rotary steerables and the drill-bit.
By detailing the exact nature of vibration at the underreamer, the present invention would be able to alert the driller when vibration reaches a certain level, therefore highlighting a change in drilling parameters or geological conditions that have caused such a change. Previously, this would not be possible and drilling delays could occur.
Previously, to overcome the lack of underreaming drilling data the industry has relied on models of the bit and underreamer wear in varying formations to investigate the effects that formation loading has on both. However, the models are based on predicted values rather than actual measurements. In this way, the present invention would not only optimise drilling during underreaming operations but also provide for accurate input data for modelling drilling dynamics.
The present invention would characterize underreamer dynamics during drilling and would highlight wear and avoid premature failures due to tool design weak spots or usage related to surface or downhole parameters as well as to optimise the rate of penetration and hole cleaning.
In the aspects of a sensing underreamer tool capable of measuring drilling dynamics and eliminating downtime and premature failures, the present invention is differentiated from the prior art underreamers. These are unsatisfactory as they there are no actual underreaming drilling dynamics measurements whether direct or inferred.
It is unsatisfactory to depend on indirect indicators such as whether cutter blocks are open or closed or whether fluid pathways are open and a pressure spike is seen at the rig floor to indicate activation. Such indicators do not provide actual measurements of the underreamed well-bore underreamed nor do they provide verification of underreaming performance; they simply give information on the mechanical or hydraulic status of an aspect of the tool which may or may not lead to the desired well diameter.
To those skilled in the art, it is known that the industry relies on even more rudimentary and time-consuming indicators of verification such as an increase in drilling torque as cutters interact with the formation or even pulling up the drill-string and underreamer to the previous hole size in order to see whether the top-drive stalls as the bottom-hole assembly gets stuck due to the expanded tool. Or by drilling a pilot hole section with the underreamer deactivated and pulling back into the pilot hole.
In the specific aspect of drilling dynamics and underreaming behaviour, the ability to acquire accurate data on vibration, stick-slip, loads and other accelerations by means of the present invention optimally differentiates it from prior art. Prior art underreamers do not provide for in-situ data measurements on drilling dynamics or loads and therefore their performance, design or configuration cannot be optimized from one job to another.
A major drawback of prior art underreamers is their cutting performance in terms of maintaining similar rates of penetration to the bit. To one skilled in the art, it is known that the bit has optimized designs due to the well characterized drilling dynamics which is well understood by means of measurement-while-drilling data acquired in the pilot-hole. Further cutter element placements and nozzle locations are optimized in the drill-bit and not necessarily so in the underreamer and this often leads to the bit outperforming the underreamer.
Consequently, this leads to either a separate underreaming run after drilling the section, or leads to the underreaming-while-drilling itself taking several attempts before a complete section is underreamed satisfactorily. In terms of drilling dynamics, the optimised drill-bit drills at a faster rate of penetration than the underreamer which has trouble maintaining similar rates of penetration. Due to the distances between the bit and underreamer which maybe 120′ or more, the bit may have exited a hard formation or layer while the underreamer may just be entering the earlier hard formation or hard layer as it is may not be connected directly to the bit. The prior art underreamers do not provide for measurements of the drilling dynamics concentrated at the underreamer.
Therefore, the prior art does not lend itself to a reliable or certain means of measuring underreaming drilling dynamics in real-time or memory mode.
Further the prior art perpetuates drilling inefficiencies due to the uncertainty of actual vibrations at the underreamer.
Further the prior art does not provide for accurate input into underreaming and drilling models.
Further the prior art does not allow for the timely identification of vibration modes or their correction in real-time.
SUMMARY OF THE INVENTION
The present invention has for a principal object to provide an improvement on the prior art wherein the actual drilling loads and vibration experiences in the underreamed hole is measured directly in real time, that is to say simultaneously with, or immediately after, an expansion operation.
The invention seeks to meet the need for an integrated underreamer and drilling dynamics sensor, which provides for real time drilling dynamics performance verification and automated troubleshooting in the underreamed hole. This has not been forthcoming in the prior art.
The present invention seeks to provide accurate input into underreaming and drilling models by using real-time or memory mode data based on in-situ vibration levels rather than the predicted values.
The present invention optimizes drilling efficiency by identifying the optimal operational parameters to ensure minimized vibration thereby increasing tool life and minimizing the need for corrective underreaming runs by providing real-time drilling dynamics data which allows the driller to respond earlier thereby saving time and money.
It is thus an object of the present invention to provide sensors integrated within an underreamer, enabling the integrated device to give immediate measurement of the vibration levels sustained during the wellbore-widening operation and, if these are found to be critically high, to automatically reconfigure drilling parameters to bring vibration levels to satisfactory levels in real-time or to perform such analysis in memory mode and provide input for drilling dynamics models.
Although underreaming is a principal route to wellbore enlargement, the invention envisages alternative enlargement means similarly integrated with sensor measurements of the enlarged bore. These alternative means could include bicentre bits, fixed wing bits, eccentric underreamers and expandable bits.
It is a further object to provide a tool capable of simultaneously conducting well-bore enlargement, measuring vibration or stick/slip levels within the enlarged wellbore, taking calliper measurements preferably by an acoustic echo-pulser and sensor, and verifying performance through a processor arrangement that uses sensor data to detect undergauge hole and conducts diagnostics according to a logic circuit in order to ensure the underreamer is functioning correctly. If the corrective steps have been taken and the calliper indicates that the planned hole diameter is still not being delivered a signal may be sent to the rig-surface or to the location of the operating engineer so that further remedial action can be taken, such as tool replacement. A memory mode may store sensor information that can be downloaded at surface when the tool is retrieved, or sent to the surface by telemetry.
The tool may also have a built-in link to a mud-pulse telemetry system to allow real-time monitoring of the under-reaming operation. One or more sensors may be optimally spaced in order to detect a number of conditions during a given time period within the enlarged wellbore.
A keyway may provide a channel for wiring from the sensors to the processor and transponder. The wiring can be used to transmit data retrieved by the vibration sensors, as well as positional data from the mechanical blocks, to the processor and transponder. The keyway may be sealed and filled with a means to absorb vibration such as silicon gel or grease and to maintain wires in position.
The transponder converts data so that it can be transmitted and is linked to the mud-pulser which transmits the data to surface using a series of binary codes at a given frequency using drilling fluid as means of mud pulsing. Other means of data transfer may be used such as wireless transmission short hop using radio frequency or electro-magnetic pulses or fibre-optics. This allows up and downlink of the tool in order to receive and transmit data and commands.
At surface a transducer may be incorporated within a decoder housing which decodes the binary code and may link to the driller's terminal or may be yet further transmitted by satellite or other means to a remote operations centre.
These and other objects will emerge from the following description and the appended claims.
In one aspect, the invention provides an expansion and sensing tool comprising a tool body, means for attaching the tool body directly or indirectly to a support whereby it can be rotated and moved axially along a borehole below a restriction, at least one expansion element adapted to be extendable from the tool body to an expansion diameter greater than the restriction, and sensing means housed within the tool body and adapted to measure drilling dynamics as expanded by the expansion element during or immediately after expansion. The support may typically be a drill string or an extended length of coiled tubing, as used in downhole operations in oil and gas fields.
In preferred embodiments of the invention, the expansion operation is an underreaming application, and expansion elements comprise a set of cutter blocks optimally configured with cutter inserts and nozzles. Alternatively, the expansion elements may comprise expansion blocks, which may be of similar construction to the cutter blocks, but having outer surfaces where cutter elements may be replaced by a hardened material. Such expansion blocks may simply bear under pressure against the inside of a tubular wall, with sufficient force to deform it outwardly to a larger diameter. In yet another alternate configuration, the same blocks may simply bear against the underreamed wellbore in order to stabilize the tool within the wellbore without enlarging the bore. The same blocks maybe received within an additional section of the tool or a separate steel body suitably prepared to provide a means of stabilization to the expansion operation. Alternatively, the same blocks maybe received within an additional section of the tool or a separate steel body suitably prepared to provide a means of stabilization for underreaming applications.
It is to be noted that the description herein of the structure and operation of cutter or expansion blocks is applicable generally, irrespective of function, except to the extent that cutter inserts may be provided specifically for underreaming purposes and removed for expansion purposes.
The tool body is typically a cylindrical high grade steel housing adapted to form part of a bottom-hole assembly (BHA). Thus the means for attaching the tool body to the support, whether it is a drill string or coiled tubing, may comprise a screw thread provided on the tool body which is engageable with a drill collar. The attachment to the drill string need not be direct, but may be indirect, as there will typically be many different functional elements to be included in the long and narrow BHA, and the arrangement of the successive elements may vary. The lower end of the BHA may be the drill bit, or a bull nose, and in between there may or may not be a means for directional control such as a rotary steerable system. The tool body may be provided with a through passage for the flow of drilling fluid from the drill string.
The set of cutters may comprise a cutter block carrying a plurality of cutter elements directed outwardly of the tool body. The cutter block may be received within the tool body in a cutter block chamber having an open mouth, and the cutter may be extendable from the chamber through the chamber mouth with the cutter elements projecting from the tool body, and retractable back into the chamber. The cutter elements may be polydiamondcrystalline inserts, or other inserts according to requirements.
The tool may then be provided with means for extending and retracting the cutter block from and into the cutter block chamber. The microprocessor control means may be suitably adapted to receive drilling dynamics data from the sensor means and to control the drilling operation or the position of the block in response thereto.
The tool may comprise means for monitoring the extension and retraction positions of the cutter block in the cutter block chamber. The tool normally comprises a plurality of such cutter blocks, arranged symmetrically around the tool. Two cutter blocks would be on opposite sides of the tool, three blocks would be separated by 120 degrees, four by ninety degrees, and six by sixty degrees. In operation, the underreaming tool is typically rotated on the drill string as well as being moved axially along the wellbore.
In accordance with a particularly preferred aspect of the invention, the cutter block is provided with an internal duct for directing drilling fluid from a source to an external nozzle among the cutter elements. The source of drilling fluid may be the drill-string or other support for the tool, and the aforementioned through passage for the flow of drilling fluid from the drill string to the drill bit. Alternatively or additionally, the tool body may be provided with an internal duct receiving a source of drilling fluid flowing to an external nozzle adjacent the set of cutters. In each case, the nozzle provides a fluid flow that can help to keep the cutters clean and prevent the build-up of clogging debris from the reaming operation, remove such material altogether from the underreaming zone, and provide a cooling and lubricating function for the cutters.
In a preferred aspect the present invention incorporates a non-mechanical means of wellbore diameter measurement which is practically applicable and may be an acoustic calliper.
In another preferred aspect of the present invention housing for a mechanical calliper is provided within the cutter block which offers a robust location. This has not been possible with previous underreamer blocks due to their inherent design limitations which rely on the block base as a retention mechanism or hydraulic activation through drilling fluid pressure.
The calliper means may typically be housed within the tool body above the underreamer, but in a variation a mechanical caliper may be located within the cutter block optimally located among the most radially extended cutter elements or surface.
The underreaming tool may further comprise telemetry means for communicating drilling dynamics data and control signals between the tool and a surface interface, which may, among other functions, control the drill string during the underreaming operation.
In a further aspect, the invention provides a method of operating an expansion tool to enlarge a borehole or tubular or the like to a target dimension below a restriction, which comprises locating a tool according to the invention in a borehole on a support below a restriction, extending the expansion element to an expansion diameter greater than the restriction, in a preferred embodiment a set of cutters to an underreaming diameter greater than the restriction, rotating the tool and moving it axially along the borehole on the drill string or other support, measuring drilling dynamics by the vibration sensor means, measuring the bore diameter by the calliper means, and continuing the expansion operation until the target dimension is achieved.
In accordance with the method of the invention, the tool may be provided with expansion element extension control means responsive to dimension data received from the sensor means. In this way, an integrated tool which is capable of detecting vibrations and correcting it may be realised. The drilling dynamics data may prompt a surface monitor to signal an opportunity for operator intervention.
Thus, in the case of an underreaming tool with vibration sensing means, data from a sensor may be transmitted to a processor which may use this data to correlate whether vibration levels exceed acceptable levels. Where the processor detects a fault or difference, it automatically troubleshoots the fault using a logical procedure.
For example, the processor may be programmed with a logic circuit which can be configured in any number of ways so as to optimize performance. An exemplary configuration may involve the circuit to first establish vibration levels. If these exceed given limits then it can alert the user by means of mud pulse telemetry, fibre optics or other data transmission to check operational parameters such as weight or surface rotational speed. The skilled man will readily appreciate that other procedures may be implemented by the logic circuit within the processor, which can be programmed to cover other scenarios.
The expansion block means may comprise a cutter block carrying cutter elements directed outwardly of the tool body.
In a still further aspect, the invention provides an underreaming tool comprising a tool body and a cutter block carrying a plurality of cutter elements directed outwardly of the tool body, wherein the cutter block is received within the tool body in a cutter block chamber having an open mouth, and means for extending the cutter block from the chamber through the chamber mouth with the cutter elements projecting from the tool body, and for retracting the cutter block back into the chamber, wherein the cutter block is provided with an internal duct open to a source of drilling fluid to an external nozzle among the cutter elements.
Alternatively, other expansion block means may replace the cutter block with its cutter elements.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are illustrated by way of non-limiting examples in the accompanying drawings, in which:
FIG. 1 is a general diagrammatic view of an oil or gas well showing surface structures and the underground wellbore, with a tool in accordance with the invention as part of a bottomhole assembly;
FIG. 2 a is a side elevation, part cut away to show the expansion elements in a deactivated state, of the tool of FIG. 1 ;
FIG. 2 b is a side elevation corresponding to FIG. 2 a showing the expansion elements in an activated state;
FIG. 3 is a diagrammatic cross section through an underreaming and sensing tool in accordance with the invention similar to that shown in the previous Figures, but having an additional stabiliser section at the trailing uphole end;
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1 , an exemplary exploration or production rig comprises a surface structure 10 at the wellhead, a wellbore 20 , and a drill string 30 in the wellbore with a bottom-hole assembly 40 at its lower end. The bottom-hole assembly includes an underreamer sensing tool 50 in accordance with the invention, and a drill-bit (not shown).
The integrated expansion and sensing tool 50 is illustrated in FIGS. 2 a and 2 b , and comprises a tubular steel body 52 provided with a drilling collar 54 at its downhole end and a mud-pulser 56 at its other end, which is adapted to be engaged by a further drill collar (not shown) to connect it other elements of the bottom-hole assembly 40 , and then to the drill string 30 .
The tool body also carries a vibration sensor 76 and an expansion element assembly 60 between the vibration sensor and the drill collar 54 . The expansion element assembly 60 comprises a number of expansion blocks 62 disposed symmetrically, radially around the tool body 52 , and in the deactivated condition shown in FIG. 2 a the blocks are withdrawn into the tool body, but in the activated condition shown in FIG. 2 b the blocks are extended beyond the tool body against the wellbore 20 . An exemplary configuration may involve the circuit to first cross check the cutter block positional data from a magnetic strip 96 and sensor 94 which is placed on each cutter block and its housing. The signal that is constantly created by the magnetic strip is at strongest when the block is fully extended and the strip 96 and sensor 94 are aligned. In this way, it can be seen whether the block has actually been extended. If the block has 10 been extended yet the caliper data shows that the actual wellbore is below the planned wellbore size, then it can alert the user by means of mud pulse telemetry to check operational parameters such as drilling fluid pump rates or surface rotational speed.
FIG. 3 illustrates diagrammatically the aforementioned elements of the tool 50 , together with a stabilizer section 61 .
As the sensor means 76 indicated in FIG. 3 , further sensors may be incorporated in 64 or 66 . Data is processed using a micro-processor 68 , shown in two alternative locations, that correlates data from the sensor 66 to detect a critical condition or simply store data for further analysis. The tool is also programmed and automated to conduct diagnostics according to a logic circuit or diagnostic program stored in processor 68 in order to ensure the underreamer is functioning correctly. Once corrective steps have been taken, and if drilling dynamics are still not optimised, an alert signal is sent via the mud-pulser 56 to the rig-surface 10 or to a remote operator so that further remedial action such as the replacement of the BHA 40 can be considered. A memory module associated with processor 68 may store sensor information that can be downloaded at surface when the tool is retrieved, or sent to the surface by telemetry through mud-pulser 56 .
The tool is provided with a built-in link to a data transfer system 56 which also serves to monitor real-time drilling dynamics. One or more sensors placed in 76 , 64 or 66 are spaced within the tool body 52 in order to detect vibrations during drilling caused by formations in the near wellbore 20 .
As further shown in FIG. 3 , a keyway 74 provides a channel for wiring from the sensors 66 to the processor 68 , and also to a transponder 72 . The wiring is used to transmit data retrieved by the sensors to the processor and transponder. The keyway may be sealed and filled with a means to absorb vibration and maintain wires in position such as silicon gel or grease.
The transponder 72 converts data from microprocessor 68 so that it can be transmitted to surface 10 and is linked to the mud-pulser 56 which transmits the data to surface using a series of binary codes at a given frequency using drilling fluid as means of mud pulsation. Other means of data transfer may be used such as wireless transmission, short hop using radio frequency or electro-magnetic pulses.
FIG. 3 also shows an alternative location for a sensor, in housing 66 or 64 connected to wiring in keyway 74 and further wiring 78 to alternative processor location 68 FIG. 3 also shows a central axial through passage 90 for the flow of drilling fluid through the whole bottom-hole assembly 40 .
The sensor means 76 , 58 , or 64 , 66 , is typically housed within the tool body 52 above the underreamer 60 , but in a variation a caliper 76 , 122 may be located within the tool.
The tool body 52 is a cylindrical high grade steel housing adapted to form part of a bottom-hole assembly (BHA) 40 . FIG. 3 shows an internal connection 82 joining two parts of tool body 52 . At the leading downhole end of the tool is a section housing the cutter blocks 62 . Connection 82 joins this to a central section housing measurement and control functions. A further section 61 at the uphole end, joined by connection 65 , houses stabiliser blocks 63 which are constructed and housed substantially identically to the underreamer components generally designated 60 , except that in place of cutter elements on cutter blocks there is at least one surface which is hard faced or coated with a hard abrasion-resistant material. A similar construction can be used to expand a deformable bore, such as a steel tubular. The means for attaching the tool body to a drill string or coiled tubing comprises a screw thread (not shown) provided on the tool body which is engageable with a drill collar (not shown).
In this alternative configuration the tool is configured, in addition to underreaming capacity, with the underreaming tool body incorporating hard facing cutter blocks to act as a stabiliser. The hard facing acts to prevent cutter abrasion while reaming or stabilising the underreamed hole. This eliminates some of the problems associated with loss of directional control due to the undergauge stabiliser above the underreamer.
The stabiliser may be directly or indirectly connected to the underreamer and hard-wired accordingly so as to ensure the mud-pulser may transmit data to surface. The tool may be provided with a mud-pulser as a standalone tool or the mud pulser itself may be provided by a third party as would be the case when a measurement while drilling or logging while drilling suite of tools is located in the BHA below the present invention. The hard wiring configuration of the tool may be changed to suit such an application.
The tool normally comprises a plurality of such cutter blocks 62 , arranged symmetrically around the tool. Two cutter blocks are on opposite sides of the tool, three blocks are separated by 120 degrees, four by ninety degrees, and six by sixty degrees. In operation, the underreaming tool 50 is typically rotated on the drill string as well as being moved axially along the wellbore.
As noted above, the invention provides a method of operating an underreaming tool to enlarge a borehole to a target dimension below a restriction, which comprises locating a tool as claimed in any one of the preceding claims in a borehole on a drill string below a restriction, extending the set of cutters to an underreaming diameter greater than the restriction, rotating the tool and moving it axially along the borehole on the drill string, measuring drilling dynamics by the sensor means, and continuing the underreaming operation until the target depth is achieved.
In addition to the above, the tool may be provided with a caliper means and cutter extension control means responsive to dimension data received from the calliper means.
Those skilled in the art will appreciate that the examples of the invention given by the specific illustrated and described embodiments show a novel underreaming tool and system and method for underreaming, with numerous variations being possible. These embodiments are not intended to be limiting with respect to the scope of the invention. Substitutions, alterations and modifications not limited to the variations suggested herein may be made to the disclosed embodiments while remaining within the ambit of the invention. | An expansion and sensing tool ( 50 ) comprising a tool body, cutter blocks and sensors which permit simultaneous underreaming and measurement of the diameter of a wellbore ( 40 ) drilled by an oil and gas rig ( 10 ). Radially extendable cutter blocks ( 62 ) incorporating positional sensors ( 80 ) contained on the block or within the body measure the position of the cutter block relative to the tool, and a vibration sensor ( 76 ) measures vibration and underreaming wellbore dimensions in real-time. Receivers, sensors and microprocessors deliver a desired wellbore depth both simultaneously comparing and correlating measured vibration data and optimizing underreaming parameters. The tool may be optionally configured with a caliper or a stabilizer. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 10/755,183, filed Jan. 8, 2004, issued as U.S. Pat. No. 7,399,385 on Jul. 15, 2008, which is a continuation in part of U.S. patent application Ser. No. 09/881,555, filed on Jun. 14, 2001, now abandoned, the contents of which are incorporated in their entirety by reference.
BACKGROUND OF THE INVENTION
1. Field of the Art
The present invention relates generally to a sputter cathode assembly and more particularly to a high current rotating sputter cathode assembly in which the power is supplied to the cathode at a point within the sputter chamber.
2. Description of the Prior Art
Direct current (“DC”) reactive sputtering is often used for large area commercial coating applications, such as the application of thermal control coatings to architectural and automobile glazings. In this process, the articles to be coated are passed through a series of in-line vacuum chambers isolated from one another by vacuum locks. Such a system may be referred to as a continuous in-line system, or simply a glass coater.
Inside the chambers, a sputtering gas discharge is maintained at a partial vacuum pressure of about three millitorr. The sputtering gas comprises a mixture of an inert gas, such as argon, with a small proportion of a reactive gas, such as oxygen, for the formation of oxides.
Each chamber contains one or more cathodes held at a negative potential of about 200 to 1000 volts. The cathodes may be in the form of elongated rectangles, the length of which spans the width of the line of chambers. The cathodes are typically 0.10 to 0.30 meters wide and a meter or greater in length. A layer of material to be sputtered is applied to the cathode surface. The surface layer or material is known as the target or the target material. The reactive gas inside the chamber forms the appropriate compound with the target material.
Ions from the sputtering gas discharge are accelerated into the target and dislodge, or sputter off, atoms of the target material. These atoms, in turn, are deposited on a substrate, such as a glass sheet, passing beneath the target. The atoms react at the substrate surface or during passage from the target to the substrate with the reactive gas in the sputtering gas discharge to form a thin film.
The above glass coating process was made commercially feasible by the development of the magnetically-enhanced planar magnetron. This magnetron has an array of magnets arranged in the form of a closed loop and mounted in a fixed position behind the target. A magnetic field in the form of a closed loop is thus formed in front of the target plate. The field causes electrons from the discharge to be trapped in the field and travel in a spiral pattern, which creates a more intense ionization and higher sputtering rates. Appropriate water cooling may be provided to prevent overheating of the target. The planar magnetron is further described in U.S. Pat. No. 4,166,018 which is herein incorporated by reference for everything it teaches.
The rotary or rotating cylindrical magnetron was developed to overcome some of the problems inherent in the planar magnetron. The rotating magnetron uses a cylindrical cathode and target. The cathode and target are rotated continually over a magnetic array which defines the sputtering zone. As such, a new portion of the target is continually presented to the sputtering zone, which eases the cooling problem and allows higher operating powers to be utilized. The rotation of the cathode also insures that the target erosion zone comprises the entire circumference of the cathode covered by the sputtering zone. This increases target utilization. The rotating magnetron is described further in U.S. Pat. Nos. 4,356,073 and 4,422,916, the entire disclosures of which are hereby incorporated by reference.
The rotating magnetrons, while solving some problems, present others. Particularly troublesome has been the development of suitable apparatus for driving and supporting the magnetron in the coating chamber. Conventional rotating cathode bodies consist of a rotating cylinder supported within a fixed housing. The housing is connected with a vacuum chamber in which the sputtering process takes place. In order to maintain the integrity of the vacuum chamber, it is necessary to provide a seal between the rotating cathode body and the fixed housing. Vacuum and rotary water seals have been used to seal around a drive shaft and cooling conduits which extend between the coating chamber and the ambient environment. However, such seals have a tendency to develop leaks under conditions of high temperature and high mechanical loading. Various mounting, sealing, and driving arrangements for cylindrical magnetrons are described in U.S. Pat. Nos. 4,443,318; 4,445,997; and 4,466,877, the entire disclosures of which are hereby incorporated by reference. These patents describe rotating magnetrons mounted horizontally in a coating chamber and supported at both ends.
A preferred seal used to solve the above problems is one which uses a ferro-fluid to make the seal. This consists in part of a fluid suspension of microscopic-magnetic particles in a carrier liquid. The fluid is held in place by a magnetic field provided by an assembly of permanent magnets and steel.
Another troublesome sputtering problem has been an arcing phenomena, which is particularly troublesome in the DC reactive sputtering of silicon dioxide and similar materials such as aluminum oxide and zirconium oxide. As DC power, and therefore voltage, is increased, the charge on the rotating cathodesc tends to build up. Once the charge has built to a certain level, the charge will dissipate by arcing. Insulating materials like silicon dioxide are particularly useful to form high quality, precision optical coatings such as multilayer, antireflection coatings and multilayer, enhanced aluminum reflectors. In addition, when faster sputtering is desired, the power supplied must also be increased, resulting again in undesirable arcing.
Perturbation of the sputtering conditions due to arcing is especially detrimental to a cost effective operation, as any article being coated when an arc occurs will most likely be defective. For instance, the article may be contaminated by debris resulting from the arc, or it may have an area with incorrect film thickness caused by temporary disruption of the discharge conditions. Furthermore, the occurrence of arcs increases with operating time, and eventually reaches a level which requires that the system be shut down for cleaning and maintenance.
One way to avoid the problem of arcing is to avoid using a high DC current and instead to use fluctuating power sources, such as an alternating current (“AC”) source or a square or pulsed DC power source. Oscillating current constantly switches the power supplied to the rotating member, as fast or faster than 50 KHz, constantly relieving the charge build up before it can cause an arc. Arcing is thereby minimized or eliminated.
Utilizing a fluctuating electrical current, however, gives rise to other types of problems. When the rotating cathodes are powered by an oscillating current power supply, any electrically conductive part near the path of the electrical current will be subject to heating via magnetic induction. This is generally not a problem at relatively low current. However, as frequency and/or current are increased, the rate of inductive heating becomes more and more significant and problematic. High frequency and current may be desired because some materials require a higher power density to be sputtered efficiently, such as when sputtering TiO 2 , SiO 2 or Al 2 O 3 . Furthermore, to maintain the same power density over a long cathode requires more current, further exacerbating the heating problem. Finally, a higher current and frequency increases the overall sputter rate, and therefore the line speed, of the sputtering operation, resulting in a more efficient production rate.
The electrical induced heating effect is even more of a problem when ferro-fluid seals are used. Ferro-magnetic materials, like the seal, magnify the induced inductive heating effect by focusing the induced magnetic field within themselves. As the current and frequency of the oscillating power supply increases, the seal is heated. If the currency and frequency are high enough, the seal overheats and fails. This failure is usually catastrophic to the sputtering process and thus costly to manufacturing. Additionally, the inductive heating represents a waste of energy and thus reduced efficiency in the sputtering process.
Accordingly, there is a need in the art for an improved sputtering cathode assembly and process which minimizes or eliminates inductive heating when using an fluctuating power supply, thereby facilitating the use of higher oscillation frequencies and currents. This in turn facilitates the more efficient sputtering of materials which require high power densities, such as the reactive sputtering of TiO 2 , SiO 2 and Al 2 O 3 , and significantly increases the sputter rate, and thus the line speed, of sputtering operations.
SUMMARY OF THE INVENTION
In contrast to the prior art, the present invention provides a method and apparatus for minimizing or eliminating the induction heating in an oscillating current sputter process, and thus facilitates the more efficient sputtering of materials requiring high power density. Furthermore, an increase in sputter rate and sputter line speed of all sputter processes may be achieved by using the present invention with oscillating power. More specifically, the present invention relates to an oscillating powered cathode assembly which minimizes, if not eliminates, inductive heating in the rotary seal, main bearings and other cathode parts, and an oscillating power sputter method for accomplishing the same.
The production of magnetically induced heating is accomplished in the present invention by providing the power connection to the rotating cathode in a manner which does not produce a magnetic field through the area where heating previously occurred; in other words, the inducted field in the region around the rotary seal is substantially eliminated. One specific embodiment for accomplishing this in accordance with the present invention is to feed the two power leads into the sputter chamber in close proximity to one another. Since each of the power leads has the current moving in the opposite direction, the magnetic fields of the two legs will cancel each other. A modification of this embodiment is to provide a coaxial power feed. The ends of the power leads, inside the sputter chamber, are connected with the rotating cathode. This can be accomplished by a variety of means including a conventional electrical brush assembly.
A further embodiment, however, provides a cathode assembly in which the power is routed through the cathode support housing itself. In this embodiment, it is necessary for the housing to be constructed of an electrically conductive material. It is also preferable, although not required, for this housing to be generally cylindrical. With this embodiment, any induced magnetic field inside the generally cylindrical housing or current path is eliminated. Thus, the ferro-fluid and other ferro-magnetic components within the housing are in a field free region and thus not subject to inductive heating.
Another embodiment of the present invention may comprise a cathode, a vacuum chamber surrounding at least a portion of said cathode, said vacuum chamber defined by a chamber housing connected and sealed relative to said cathode, a power supply which supplies a current to the cathode, and a power connection between said power supply and said cathode which allows the current to flow between the same, said power connection with said cathode being at a point within said vacuum chamber.
Another embodiment of the present invention may comprise a sputter chamber, one or more rotatable sputter cathodes with at least a portion of each of said cathodes positioned within said sputter chamber and a portion of said cathode disposed inside of a housing, and a rotary vacuum seal operably positioned between said cathode and said housing, means for supplying a current to the rotatably sputter cathode inside of the sputter chamber, thereby avoiding inductive heating of the vacuum seal.
Accordingly, it is an object of the present invention to provide a sputter cathode assembly using oscillating power with a reduction or elimination of inductive heating.
Another object of the present invention is to provide a rotating sputter cathode assembly capable of utilizing a high frequency and high current oscillating power source.
Another object of the present invention is to provide an oscillating powered rotating cathode assembly which can be used with a ferro-magnetic rotary seal.
A further object of the present invention is to provide an oscillating powered sputter cathode assembly in which the power is provided to the rotating cathode at a point within the sputter chamber.
A still further object of the present invention is to provide a method for sputtering in which the inductive heating of seals and other ferro-magnetic materials is substantially reduced or eliminated and which thereby facilitates the sputtering at high frequencies and currents.
These and other objects of the present invention will become apparent with reference to the drawings, the description of the preferred embodiment and the appended claims.
SUMMARY OF THE DRAWINGS
FIG. 1 is a top plan view of one embodiment of the present invention.
FIG. 2 is a top plan view of an alternative embodiment of the present invention.
FIG. 3 is a schematic representation showing the electrical connection between the brush assembly and the cathode.
DETAILED DESCRIPTION
The present invention will be described in terms of a rotatable sputter cathode and more particularly a horizontally disposed cathode although this invention applies equally to vertically disposed cathodes. Further, the teachings of the present invention may be utilized in any type of sputter cathode, whether rotatable or not, that experiences current induced heating. Although the invention has application to cathodes using a DC power source, it has particular application to cathodes and sputtering processes driven by a fluctuating power source. This may include standard alternating current (AC), square or pulsed direct current and bipolar direct current, among others.
As shown in FIG. 1 , the present embodiment is a cantilever mounting arrangement for a rotating sputter cathode 10 disposed in an evacuable coating or vacuum chamber 12 . The coating chamber 12 may further comprise a floor 14 , a side wall 16 , a side wall 17 , and a top wall 18 connected as illustrated in FIG. 1 . The walls 14 , 16 , 17 , and 18 may be formed as one unit or may be fitted and sealed together in any manner known to those skilled in the art. As is known in the art, the vacuum chamber 12 may further comprise a vacuum seal 20 . The vacuum seal 20 may insure a positive seal between the normal atmospheric pressure outside the chamber 12 and the partial vacuum inside the chamber 12 . This seal may be made of buna or Viton o-rings, or with other materials suitable for creating vacuum seals known to those skilled in the art. To electrically isolate the cathode from the chamber, an insulator 21 is placed between the two. This material can be any insulating material that is vacuum compatible, such as Nylon, Ultem, G-10, Teflon, etc. These materials with higher temperature rates are preferred.
The rotating cathode 10 of the present embodiment may be, by way of example, approximately 160 inches long and eleven inches in diameter at the housing flange 24 . The actual magnetic array portion of such a cathode 10 that can be effectively utilized for sputtering may be approximately 124 inches in length.
As illustrated in FIG. 1 , the present invention may further comprise a drive shaft 22 , a drive shaft first end 22 a , a main housing 24 , a rotary vacuum seal 26 , and a rotatable cathode target 28 .
The drive shaft 22 of the present embodiment extends through the main housing 24 as illustrated in FIG. 1 . A drive shaft first end 22 a may extend outside of the main housing 24 and engage a drive mechanism. The rotary vacuum seal 26 may be operably situated between the drive shaft 22 and the main housing 26 . The drive shaft 22 may be in a vacuum sealed relationship with the main housing 24 by operation of the rotary vacuum seal 26 . The drive shaft 22 may be, by way of example, approximately seven inches in diameter at the flange end 22 b.
Rotary vacuum seal 26 insures that the interior of main housing 24 and the outside atmosphere are both isolated from the vacuum chamber 12 . Preferably, rotary seal 26 may be a ferrofluidic seal. As is known, a ferrofluidic seal incorporates a colloidal suspension of ultramicroscopic magnetic particles in a carrier liquid. A suitable ferrofluidic seal may be supplied by Ferrofluidic Corporation, 40 Simon Street, Nashua, N.Y. 03061. One compatible seal is Model #5C-3000-C. Other types of rotary seals for the shaft could also be employed without changing the nature and scope of the present invention. The rotary cathode target 28 is affixed to a second end 22 b of the drive shaft 22 . A magnet array 29 known to those skilled in the art to be suitable of cathode sputtering may be operably situated in the target.
As illustrated in FIG. 1 , the present embodiment may further comprise a bearing 32 , and a bearing 34 . The bearing 32 and the bearing 34 insure the smooth rotation of the drive shaft 22 relative to the main housing 24 . Utilizing two bearings 32 and 34 allows for the even distribution of the weight of the drive shaft 22 and further helps to insure the low friction rotation of shaft 22 . The bearings 32 and 34 are thus spaced along drive shaft 22 to provide the cantilever support for sputter cathode 10 . Specifically, the entire load of the magnetron may be supported by the bearings such that substantially no load may be transferred to vacuum seal 26 . In alternative embodiments, bearings 32 and 34 may be included as a single or duplex bearing. In the present embodiment, bearings 32 and 34 may be tapered roller bearings. Other types of bearings may include conventional ball bearings, cylindrical roller bearings, and drawn-cup needle roller bearings.
A drive shaft pulley may be keyed to the drive shaft and positioned in such a way to rotate the same (not shown). The drive for cylindrical magnetron may be provided by means of an electric motor. The output of the motor may be transmitted through a reduction gearbox to a gearbox pulley which may be connected with the drive shaft pulley by a drive belt (not shown).
To shield certain parts from a dielectric coating build up which may cause arcing, alternative embodiments in an incorporated shield placed around parts of the cathode that are at cathode potential and that are not intended to be sputtered. This shield is called a dark space shield because it is spaced a length away from the cathode parts that creates a dark space. A dark space is simply an area where no plasma can exist. The cathode dark space length may be about 3 mm at a pressure of about 3 millitorr and a cathode potential of about 500 volts. A dark spaced shield keeps a plasma from forming at any unwanted point that is at cathode potential and it also keeps the dielectric from forming, therefore minimizing arc events. This shield can be at ground potential or it can ‘float’ at the surrounding plasma potential if it is not in electrical contact with anything else. See U.S. Pat. No. 5,567,289 for further description, the entire contents of which are herein incorporated by reference.
The magnetic array 29 or bar may be disposed inside rotatable cathode target 28 . As shown in FIGS. 1 and 2 , the array 29 may be made up of a backing bar 29 a to which rows of bar magnets 29 b are attached. The array may be suspended from a cooling liquid input tube by a bracket 31 .
As is illustrated in FIG. 1 , the current of one embodiment of the present invention may be routed through the main housing 24 surrounding the drive shaft 22 of the rotatable sputter cathode. The electrical connection of this embodiment may further comprise a power supply 100 , a first conductive wire 102 , a brush housing 110 and electrical brushes 116 with leads 114 . In the embodiment shown in FIG. 1 , the power supply 100 may be connected to the first conductive wire 102 , which is then bolted with a lug to the main housing 24 . The brush housing 110 may be bolted to the main housing 24 on the inside of the vacuum chamber 12 .
In the present embodiment, the current flows from the power supply 100 , through the first conductive wire 102 , and into the main housing 24 . Once the current has entered the main housing 24 , it flows along its length and enters the brush housing 110 and then through the brush leads 114 into the electrical brush 116 . The brushes 116 transfer the current to the drive shaft flange 22 b and then to the rotary cathode target 28 . The main housing 24 should be manufactured of some electrically conductive substance that is also able to withstand the structural strains placed thereon. One material that may be utilized for the construction of the main housing 24 may be stainless steel, though those skilled in the art may likewise use other materials as well.
The brush housing 110 of the present invention may be operably attached to the main housing 24 and in electrical cooperation with the main housing 24 by directly bolting it to the main housing 24 . The housing 110 may be constructed of a conductive material such as stainless steel, aluminum, copper, or other material well known to those reasonably skilled in the art.
The drive shaft flange 22 b is bolted or otherwise connected to the cathode target 28 . Thus, the target 28 receives the current from the flange 22 b . In the present embodiment, the current flows into the brush housing 110 and then to the brush 116 itself through the brush leads 114 . The brush 116 is in continuous electrical contact with the flange 22 b and thus the rotary cathode 28 to provide a substantially continuous flow of current to the cathode. The power supply 100 of the present invention may be capable of providing any kind of current effective for sputtering. Preferably, the power supply 100 provide a fluctuating current that may include DC pulsed current, bipolar DC current, and standard alternating current (AC), among others.
Reference is next made to FIG. 3 showing schematically the electrical connection between the brush or electrical connection assembly and the rotating cathode. As described above, the portion of the rotating cathode to which the driving current for the sputtering process is provided includes the drive shaft 22 and the drive shaft flange 22 b . This drive shaft flange 22 b may be in the form of, or include, a slip ring or other commutator to receive current from the brush 116 . The brush 116 is part of the brush or electrical connection assembly which includes the brush housing 110 , the brush leads 114 and the brush spring 115 . The spring 115 is positioned between a portion of the housing 110 and the brush 116 and functions to bias the brush 116 toward engagement with the exterior surface of the flange or slip ring 22 b . Although the schematic in FIG. 3 shows a single brush and brush assembly, the present invention contemplates that two or more brushes may be circumferentially positioned around the shaft 22 to increase the supply of current from the brushes 116 to the rotating cathode. Preferably at least two brush assemblies and as many as four or more brush assemblies are associated with each cathode shaft.
There are a variety of materials from which the member 22 b and the brush 116 can be constructed. Preferably, however, the selected materials provide a low friction, current transferring engagement between the rotating element 22 b and the stationary brush 116 . Further, these materials should be selected so that the sliding engagement between them provides a high electrical conductivity transfer and a low voltage drop at the point of contact. Still further, the materials of these elements should be selected so that the generation of electrical noise, heat, and wear between such surfaces is kept to a minimum and the above objectives are achieved in a vacuum or substantial vacuum environment. Still further, it is preferable for the material of the brush 116 to be softer than the surface of the element 22 b so that the brush 116 , not the element 22 b , is the chosen sacrificial element. Preferably, the materials are selected so that the wear rate of the brush 116 material will exceed the wear rate of the element 22 b by a factor of at least 10.
The sliding surface of the rotating member which in the preferred embodiment is the outside surface of the element 22 b should be selected from a material having high electrical conduction characteristics. This material should also be hard enough to withstand extended use with minimal wear and should, in combination with the brush material, minimize the voltage drop at the point of contact. Various metals or metal-based materials such as stainless steel, aluminum, copper, platinum, gold, silver and nickel, among others are preferred. Copper alloys which include low-melting materials such as lead, tin and antimony may also be used. Materials such as these belong to a family of materials commonly referred to as brasses and bronzes. Aluminum bronze is an example of an alloy which may be employed for application in the present invention.
The material from which the brush 116 is construed can be any one of a variety of carbon or graphite based materials. Examples of brushes which are made from such carbon or graphite based materials are brushes commonly referred to as electrographite brushes, graphite brushes, carbon-graphite brushes, resin-bonded brushes and metal-graphite brushes, hereinafter referred to as carbon or graphite based brushes. Various brush additives can be added to these carbon or graphite based materials to improve lubrication and thus brush wear in various environments. These additives may include materials such as molybdenum disulfide and other dichalcogenides including sulfides, diselenides and ditellurides of the metals molybdenum, tungsten, niobium and tantalum. Other materials which may be helpful include metallic halides including, among others CdI 2 , PbI 2 , CdCl 2 , HgI 2 , and BaF 2 .
One preferred brush material is an electrographite, graphite, carbon-graphite, resin-bonded, or metal-graphite brush material (carbon or graphite based brush), to which has been added a small amount of molybdenum disulfide or other dichalcogenide. Dichalcogenides of particular interest for use as a brush material in the present invention are those identified above, namely, sulfides, diselenides and ditellurides of the metals molybdenum, tungsten, niobium, and tantlum. The most preferred of these is molybdenum disulfide (MoS 2 ). The most preferred brush material is a graphite brush made from natural or synthetic graphite with a small portion (preferably no more than about 10%) of molybdenum disulfide as an additive. More preferably, the brush material is constructed of a carbon or graphite based material having molybdenum disulfide present in an amount ranging from 1% to 10% by weight and most preferably ranging from 5 to 8% by weight.
The selected materials for the brush 116 and the element 22 b should preferably provide electrical conductivity or current density of at least 50 amps per square inch and more preferably at least 80 amps per square inch.
A further preferred brush material is comprised of a combination of carbon, copper, barium and iron together with minor metallic impurities and gaseous elements such as nitrogen and oxygen. More specifically, a preferred brush material of this type comprises 40-60% carbon, 20-30% copper, 1-4% barium and 0.2-0.6% iron, with the remainder comprising minor metallic impurities and gaseous elements such as nitrogen and oxygen. A most preferred material of this type is comprised of 47% carbon, 25% copper, 2.2% barium and 0.39% iron.
As the current flows through the main housing 24 of the present embodiment, the current will flow along the surface of the housing itself. Since the current runs over the surface of the main housing 24 , the field on the inside of the housing is zero. Since there is no electric field inside of the housing 24 , there is no electric field induced heating of the ferrofluidic rotary seal 26 .
In an alternative embodiment illustrated in FIG. 2 , the electrical contact between the power source 100 and the rotary cathode target 28 may further comprise a conductive wire 120 , a vacuum sealed electrical feed 122 , and the same electrical contact assembly previously described. The conductive wire 120 may be operably attached to the power source 100 at one end and to the brush housing 110 at a second end. The wire 120 may travel through the vacuum chamber wall 16 via the vacuum sealed electrical feed 122 . The vacuum sealed electrical feed 122 may be integrated into the vacuum chamber wall 17 of the vacuum chamber 12 as illustrated in FIG. 2 . The brush housing 110 may be affixed to the main housing 24 and be in connected electrical cooperation with the cathode target 28 . As will be appreciated by those skilled in the art, the vacuum sealed electrical feed 122 may be situated at any point on the vacuum chamber housing as long as it does not interfere with the operation of the other parts of the present invention rotatable sputter cathode. Furthermore, the electrical contact assembly may similarly be situated and affixed to any structure as long as it too does not interfere with the operation of the rotary sputter cathode that is the present invention.
In this embodiment, the current flows directly from the power supply 100 , through the wire 120 , and into the brush housing 110 . From there the current is transferred through the brush leads 114 , and brushes 116 , to the drive shaft flange 226 and ultimately to the cathode target 28 . Minimal electric field induced heating, if any, will occur along the length of the wire as the power and frequency level is increased, because the proximity of the electrical field generated by the two wires will cancel one another out.
In alternative embodiments, the electrical contact between the stationary housing 24 and the rotating target 28 may be comprised of a liquid contact. Liquid contacts of this nature may be comprised of a sealed liquid chamber in constant contact with a member attached around the surface of the cathode target 28 . The seal prevents the liquid from escaping. The electric current may run through a housing similar to the brush housing 110 then through the fluid connection, and into the rotary cathode 28 .
One advantage to the present invention is that it allows for the use of oscillating high current to effectuate sputtering. As previously mentioned, non-oscillating high current sputtering creates significant problems with arcing, damaging the object to be sputtered, and damaging the coating put on the surface. Switching to the oscillating current allows better sputtering by allowing a higher sputter rate without arcing. The present invention facilitates the high current sputtering to occur by bypassing the inductive heating of elements that are within or surrounding the current path. Eliminating inductive heating allows structures to be utilized near to the current path which are subject to induction. The information and examples described herein are for illustrative purposes and are not meant to exclude any derivations or alternative methods that are within the conceptual context of the invention. It is contemplated that various deviations can be made to this embodiment without deviating from the scope of the present invention. Accordingly, it is intended that the scope of the present invention be dictated by the appended claims rather than by the foregoing description of this embodiment. | The present invention is an alternating current rotary sputter cathode in a vacuum chamber. The apparatus includes a housing containing a vacuum and a cathode disposed therein. A drive shaft is rotatably mounted in the bearing housing. A rotary vacuum seal is located in the bearing housing for sealing the drive shaft to the housing. An at least one electrical contact is disposed between a power source and the cathode for transmittal of an oscillating or fluctuating current to the cathode. The electrical contact between the power source and the cathode is disposed inside of the vacuum chamber, greatly reducing, and almost eliminating, the current induced heating of various bearing, seals, and other parts of the rotatably sputter cathode assembly. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority from U.S. Provisional Patent Application Ser. No. 61/413,941, filed Nov. 15, 2010, the contents of which are hereby incorporated herein by reference.
FIELD
The present application relates generally to mobile wireless electronic messaging and, more specifically, to encrypting a message with the involvement of more than one component.
BACKGROUND
In one manner of processing (e.g., encrypting) an outgoing e-mail message, a communication application, employed by a given user, transforms the outgoing e-mail message using an algorithm with a public key half of a public-private key pair. The encrypted outgoing e-mail message may then be transmitted. Upon receiving the encrypted e-mail message, the recipient device may be configured to decrypt the received e-mail using a private key half of the public-private key pair.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made to the drawings, which show by way of example, embodiments of the present application, and in which:
FIG. 1 illustrates an overview of an example system including a mobile communication device and a wireless mail server;
FIG. 2 illustrates a schematic representation of components of the mobile communication device of FIG. 1 ;
FIG. 3 illustrates example steps in a first method of processing an electronic message at the mobile communication device of FIG. 1 , where the processing comprises signing;
FIG. 4 illustrates an example dialog to warn a user that an e-mail message will be incompletely included in a response message;
FIG. 5 illustrates example steps in the method of FIG. 3 , where the processing comprises encrypting;
FIG. 6 illustrates example steps in a second method of processing an electronic message at the mobile communication device of FIG. 1 , where the processing comprises signing;
FIG. 7 illustrates example steps in a method of processing an electronic message at the wireless mail server of FIG. 1 , in conjunction with the method of FIG. 6 ;
FIG. 8 illustrates example steps in a third method of processing an electronic message at the mobile communication device of FIG. 1 , where the processing comprises signing;
FIG. 9 illustrates example steps in a method of processing an electronic message at the wireless mail server of FIG. 1 , in conjunction with the method of FIG. 8 ;
FIG. 10 illustrates example steps of a cross-component message encryption approach;
FIG. 11 illustrates example steps in a method of participating, at the wireless mail server of FIG. 1 , in the cross-component message encryption approach of FIG. 10 ;
FIG. 12 illustrates example steps of cross-component message encryption approach distinct from the cross-component message encryption approach of FIGS. 10 and 11 ; and
FIG. 13 illustrates example steps in a method of participating, at the wireless mail server of FIG. 1 , in the cross-component message encryption approach of FIG. 12 .
DETAILED DESCRIPTION OF THE EMBODIMENTS
When a mobile wireless device is used to receive and transmit e-mail, the mobile wireless device is often associated with a mobile mail server. The mobile mail server manages the transmission of messages to the mobile wireless device to optimize use of the limited resources of a wireless communication channel in the path between the mobile wireless device and the mobile mail server. The mobile mail server may also manage messages transmitted by the mobile wireless device to optimize in a similar fashion.
For a first example of optimization of transmission of messages to the mobile wireless device, by only transmitting an initial portion of a first e-mail message to the mobile wireless device, the mobile mail server may conserve wireless resources that would otherwise be consumed by transmitting the entire first e-mail message.
It is common, in e-mail communication applications, to include the text of a received e-mail message when composing an e-mail message in response or when forwarding the e-mail message to a further recipient. However, in a mobile communication system, when sending a new e-mail message related to an original e-mail message, the mobile wireless device may only be able to include the initial portion of the original e-mail message in the new e-mail message, since the mobile wireless device may only have the initial portion of the original e-mail message available. Upon receiving the new e-mail message, the cleverly designed mobile mail server may append the remaining (i.e., non-initial) portion of the original e-mail message before forwarding the entire new e-mail message toward its destination. Conveniently, this scheme conserves wireless communication channel resources.
However, when a user of the mobile wireless device wishes to sign the new e-mail message, obtaining the efficiency of previously described schemes becomes challenging.
For example, consider receipt, at the mobile wireless device, of an initial portion of a first e-mail message. The user of the mobile wireless device reviews the initial portion of the first e-mail message and composes a response to the first e-mail message. The response may be considered a second e-mail message. The second e-mail message may be considered to have at least two portions: an “old” portion, comprising the initial portion of the first e-mail message; and a “new” portion, comprising the content composed by the user of the mobile wireless device. The user of the mobile wireless device may decide to sign the second e-mail message. Accordingly, when obtaining a signature to associate with the second e-mail message, the mobile wireless device may only obtain a hash of the second e-mail message (i.e., the old portion appended to the new portion). That is, the mobile wireless device encrypts a hash of the second e-mail message with the private key stored at the mobile wireless device. The mobile mail server would normally append the remaining (i.e., non-initial) portion of the first e-mail message to the received second e-mail message to form a complete response, before forwarding the complete response to the origin of the first e-mail message. However, since the signature received in association with the second e-mail message only relates to the old portion appended to the new portion, and not to the complete response, the mobile mail server must simply forward the second e-mail message and associated signature toward the origin of the first e-mail message.
At the origin of the first e-mail message, the recipient of the second e-mail message does not receive all of the typically appended first e-mail message content and, accordingly, may struggle with the placing of the second e-mail message properly in context.
To provide awareness to the sender of the second e-mail message (i.e., the user of the mobile wireless device) that the second e-mail message will include only a truncated version of the first e-mail message, the mobile wireless device may display a warning dialog. The warning dialog may be displayed responsive to the user of the mobile wireless device indicating, using a user interface in a message composition mode, that the second e-mail message is to be sent. The warning dialog may indicate “Warning! Your message will be truncated.” Furthermore, the warning dialog may be interactive and may require user selection of a choice before the warning dialog may be dismissed from the display. That is, the warning dialog may present choices labeled “OK” and “Cancel”. Additionally, the warning dialog may include a checkbox labeled “Don't show this dialog again”. The user may select the “OK” choice to indicate acceptance of the truncation. Alternatively, the user may select the “Cancel” choice to indicate a wish to return to composing the message. By selecting the checkbox labeled “Don't show this dialog again” and then selecting the “OK” choice, the user may effectively set a policy for the mobile wireless device, where the policy indicates that all future signed, and/or encrypted, messages are to include only a truncated version of the original received message.
Upon receiving an indication that the user has selected the “OK” choice, the mobile wireless device may proceed to transmit the second e-mail message to the mobile mail server for forwarding to the sender of the first e-mail message.
Upon receiving an indication that the user has selected the “Cancel” choice, the mobile wireless device may return the user interface to the message composition mode. Responsive to being returned to the message composition mode, the user may manipulate the user interface to copy, to a clipboard, the message that has been typed (i.e., the new portion). The user may then close the message composition user interface, return to a message list and re-open the first message. Once the initial portion of the first message is open, the user may manipulate a message viewing user interface to request, from the mobile mail server, the entire first message. The user may then manipulate the message viewing user interface to indicate a wish to compose a response to the first message. Once the message composition user interface has been opened, pre-loaded with the entirety of the first e-mail message, the user may paste the previously composed new portion from the clipboard to the message composition area in the message composition user interface, thereby creating a third e-mail message. The third e-mail message may be distinguished from the second e-mail message in that the third e-mail message includes the entirety of the first e-mail message and the second e-mail message only includes a truncated version of the first e-mail message. The user may then create a signature for the third e-mail message and indicate that the third e-mail message and the signature are to be sent.
One can see that including an entire original message in a signed response can require manually carrying out some potentially tedious and complex steps.
By arranging assembly, at a server, of a composite message from a new message and an original message and arranging encryption and signing of the composite message in cooperation with a wireless messaging device, operational complexity on the part of the user can be obviated.
In an aspect of the present disclosure there is provided a method of processing an electronic message at a mobile wireless communication device. The method includes detecting receipt of an instruction to encrypt and transmit a composite message, where the composite message includes a new message and an original message, obtaining cryptographic information for use in carrying out the encryption request, transmitting the new message to a server associated with the mobile wireless communication device and transmitting an encryption request to the server, the encryption request including the cryptographic information and specifying the original message. In other aspects of the present application, a mobile wireless communication device is provided for carrying out this method and a computer readable medium is provided for adapting a processor to carry out this method.
In another aspect of the present disclosure there is provided a method of processing an electronic message. The method includes detecting receipt of a message processing request for encryption and transmission of a composite message, where the composite message includes a new message and an original message, the message processing request including the new message, an indication of the original message and cryptographic information for use in the encryption, creating the composite message from the new message and the original message, employing a first portion of the cryptographic information to encrypt the composite message to form an encrypted composite message and transmitting the encrypted composite message. In other aspects of the present application, a mail server is provided for carrying out this method and a computer readable medium is provided for adapting a processor to carry out this method.
Other aspects and features of the present application will become apparent to those of ordinary skill in the art upon review of the following description of specific embodiments of the application in conjunction with the accompanying figures.
Referring to FIG. 1 , an overview of an example system for use with the embodiments described below is shown. One skilled in the art will appreciate that there may be many different topologies, but the system shown in FIG. 1 helps demonstrate the operation of the systems and methods described in the present application. For example, there may be many mobile communication devices connected to the system that are not shown in the overview of FIG. 1 .
FIG. 1 shows a mobile wireless device in the form of a mobile communication device 100 . It will be appreciated by those skilled in the art that the mobile communication device 100 may comprise any computing or communication device that is capable of connecting to a network by wireless means, including, but not limited, to personal computers (including tablet and laptop computers), personal digital assistants, smart phones, and the like. It will further be appreciated by those skilled in the art that these devices may be referred to herein as computing devices or communication devices, and may have principal functions directed to data or voice communication over a network, data storage or data processing, or the operation of personal or productivity applications; those skilled in the art will appreciate that terminology such as “mobile device”, “communication device”, “computing device”, or “user device” may be used interchangeably.
The mobile communication device 100 may, for example, be connected to an Internet Service Provider on which a user of the system of FIG. 1 , likely the user associated with the mobile communication device 100 illustrated in FIG. 1 , has an account.
The mobile communication device 100 may be capable of sending and receiving messages and other data via wireless transmission and reception, as is typically done using electromagnetic waves in the radio frequency (RF) spectrum. The exchange of messages and other data may occur, for instance, between the mobile communication device 100 and a base station in a wireless carrier network 106 . The mobile communication device 100 may receive data by other means, for example through a direct connection to a port provided on the mobile communication device 100 . An example of such a direct connection is a Universal Serial Bus (USB) link.
As illustrated in FIG. 1 , the wireless carrier network 106 connects to a wide area network 114 , represented as the Internet, via a wireless infrastructure 110 . The wireless infrastructure 110 incorporates a wireless gateway 112 for connecting to the Internet 114 .
A connection between the mobile communication device 100 and the Internet 114 allows the mobile communication device 100 to access a wireless mail server 118 . The wireless mail server 118 may include a processor 117 and a memory 119 . The wireless mail server 118 may be grouped together with other servers (not shown) in an enterprise 120 . Also connected to the Internet 114 may be a representative message origin 130 . The mobile communication device 100 may store a private cryptographic key 124 that is associated with a corresponding public cryptographic key.
FIG. 2 illustrates the mobile communication device 100 . The mobile communication device 100 includes a housing, an input device (e.g., a keyboard 224 having a plurality of keys) and an output device (e.g., a display 226 ), which may be a full graphic, or full color, Liquid Crystal Display (LCD). In some embodiments, the display 226 may comprise a touchscreen display. In such embodiments, the keyboard 224 may comprise a virtual keyboard. Other types of output devices may alternatively be utilized. A processing device (a processor 228 ) is shown schematically in FIG. 2 as coupled between the keyboard 224 and the display 226 . The processor 228 controls the operation of the display 226 , as well as the overall operation of the mobile communication device 100 , in part, responsive to actuation of the keys on the keyboard 224 by a user. Notably, the keyboard 224 may comprise physical buttons (keys) or, where the display 226 is a touchscreen device, the keyboard 224 may be implemented, at least in part, as “soft keys”. Actuation of a so-called soft key involves either touching the display 226 where the soft key is displayed or actuating a physical button in proximity to an indication, on the display 226 , of a temporary action associated with the physical button.
The housing may be elongated vertically, or may take on other sizes and shapes (including clamshell housing structures). Where the keyboard 224 includes keys that are associated with at least one alphabetic character and at least one numeric character, the keyboard 224 may include a mode selection key, or other hardware or software, for switching between alphabetic entry and numeric entry.
In addition to the processor 228 , other parts of the mobile communication device 100 are shown schematically in FIG. 2 . These may include a communications subsystem 202 , a short-range communications subsystem 204 , the keyboard 224 and the display 226 . The mobile communication device 100 may further include other input/output devices, such as a set of auxiliary I/O devices 206 , a serial port 208 , a speaker 211 and a microphone 212 . The mobile communication device 100 may further include memory devices including a flash memory 216 and a Random Access Memory (RAM) 218 and various other device subsystems 220 . The mobile communication device 100 may comprise a two-way radio frequency (RF) communication device having voice and data communication capabilities. In addition, the mobile communication device 100 may have the capability to communicate with other computer systems via the Internet.
Operating system software executed by the processor 228 may be stored in a computer readable medium, such as the flash memory 216 , but may be stored in other types of memory devices, such as a read only memory (ROM) or similar storage element. In addition, system software, specific device applications, or parts thereof, may be temporarily loaded into a volatile store, such as the RAM 218 . Communication signals received by the mobile device may also be stored to the RAM 218 .
The processor 228 , in addition to its operating system functions, enables execution of software applications on the mobile communication device 100 . A predetermined set of software applications that control basic device operations, such as a voice communications module 230 A and a data communications module 230 B, may be installed on the mobile communication device 100 during manufacture. A message processing module 230 C may also be installed on the mobile communication device 100 during manufacture, to implement aspects of the present disclosure. As well, additional software modules, illustrated as an other software module 230 N, which may be, for instance, a PIM application, may be installed during manufacture. The PIM application may be capable of organizing and managing data items, such as e-mail messages, calendar events, voice mail messages, appointments and task items. The PIM application may also be capable of sending and receiving data items via a wireless carrier network 106 represented by a radio tower. The data items managed by the PIM application may be seamlessly integrated, synchronized and updated via the wireless carrier network 106 with the device user's corresponding data items stored or associated with a host computer system.
Communication functions, including data and voice communications, are performed through the communication subsystem 202 and, possibly, through the short-range communications subsystem 204 . The communication subsystem 202 includes a receiver 250 , a transmitter 252 and one or more antennas, illustrated as a receive antenna 254 and a transmit antenna 256 . In addition, the communication subsystem 202 also includes a processing module, such as a digital signal processor (DSP) 258 , and local oscillators (LOs) 260 . The specific design and implementation of the communication subsystem 202 is dependent upon the communication network in which the mobile communication device 100 is intended to operate. For example, the communication subsystem 202 of the mobile communication device 100 may be designed to operate with the Mobitex™, DataTAC™ or General Packet Radio Service (GPRS) mobile data communication networks and also designed to operate with any of a variety of voice communication networks, such as Advanced Mobile Phone Service (AMPS), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA), Personal Communications Service (PCS), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), Universal Mobile Telecommunications System (UMTS), Wideband Code Division Multiple Access (W-CDMA), High Speed Packet Access (HSPA), etc. Other types of data and voice networks, both separate and integrated, may also be utilized with the mobile communication device 100 .
Network access requirements vary depending upon the type of communication system. Typically, an identifier is associated with each mobile device that uniquely identifies the mobile device or subscriber to which the mobile device has been assigned. The identifier is unique within a specific network or network technology. For example, in Mobitex™ networks, mobile devices are registered on the network using a Mobitex Access Number (MAN) associated with each device in DataTAC™ networks, mobile devices are registered on the network using a Logical Link Identifier (LLI) associated with each device. In GPRS networks, however, network access is associated with a subscriber or user of a device. A GPRS device therefore uses a subscriber identity module, commonly referred to as a Subscriber Identity Module (SIM) card, in order to operate on a GPRS network. Despite identifying a subscriber by SIM, mobile devices within GSM/GPRS networks are uniquely identified using an International Mobile Equipment Identity (IMEI) number.
When required network registration or activation procedures have been completed, the mobile communication device 100 may send and receive communication signals over the wireless carrier network 106 . Signals received from the wireless carrier network 106 by the receive antenna 254 are routed to the receiver 250 , which provides for signal amplification, frequency down conversion, filtering, channel selection, etc., and may also provide analog to digital conversion. Analog-to-digital conversion of the received signal allows the DSP 258 to perform more complex communication functions, such as demodulation and decoding. In a similar manner, signals to be transmitted to the wireless carrier network 106 are processed (e.g., modulated and encoded) by the DSP 258 and are then provided to the transmitter 252 for digital to analog conversion, frequency up conversion, filtering, amplification and transmission to the wireless carrier network 106 (or networks) via the transmit antenna 256 .
In addition to processing communication signals, the DSP 258 provides for control of the receiver 250 and the transmitter 252 . For example, gains applied to communication signals in the receiver 250 and the transmitter 252 may be adaptively controlled through automatic gain control algorithms implemented in the DSP 258 .
In a data communication mode, a received signal, such as a text message or web page download, is processed by the communication subsystem 202 and is input to the processor 228 . The received signal is then further processed by the processor 228 for output to the display 226 , or alternatively to some auxiliary I/O devices 206 . A device user may also compose data items, such as e-mail messages, using the keyboard 224 and/or some other auxiliary I/O device 206 , such as a touchpad, a rocker switch, a thumb-wheel, a trackball, a touchscreen, or some other type of input device. The composed data items may then be transmitted over the wireless carrier network 106 via the communication subsystem 202 .
In a voice communication mode, overall operation of the device is substantially similar to the data communication mode, except that received signals are output to the speaker 211 , and signals for transmission are generated by a microphone 212 . Alternative voice or audio I/O subsystems, such as a voice message recording subsystem, may also be implemented on the mobile communication device 100 . In addition, the display 226 may also be utilized in voice communication mode, for example, to display the identity of a calling party, the duration of a voice call, or other voice call related information.
The short-range communications subsystem 204 enables communication between the mobile communication device 100 and other proximate systems or devices, which need not necessarily be similar devices. For example, the short-range communications subsystem may include an infrared device and associated circuits and components, or a Bluetooth™ communication module to provide for communication with similarly-enabled systems and devices.
In overview, the mobile communication device 100 receives an initial portion of a first e-mail message from the wireless mail server 118 , where the first e-mail message has originated at the representative message origin 130 . The user of the mobile communication device 100 manipulates the mobile communication device 100 to invoke a message composition user interface preloaded with the received initial portion of the first e-mail message and composes a new portion. Where the user has specified that the message is to be processed (e.g., signed and/or encrypted), responsive to the user indicating that the message is to be sent, aspects of the present disclosure allow for the processing of a new message that includes the new portion and the entirety of the first e-mail message.
For example, the message composition user interface may allow the user to specify that the message is to be signed. Typically, when the user has indicated that the message is to be sent, the message composition user interface prompts the user for a password associated with a key store in which the private cryptographic key 124 is stored. Upon verifying a received password, the processor 228 executes a message signing algorithm to generate a signature by, first, generating a hash of the message and, second, encrypting the hash with the private cryptographic key 124 .
In a first cross-component message processing approach, some automation is provided to the complex operations. Responsive to the user indicating that a reply message with truncated original message is to be sent, it is proposed herein to prompt the user with a dialog that includes a user option to “Download Original”. Responsive to receiving an indication that the “Download Original” user option has been selected, the processor 228 may automatically download the remainder of the original message and append the remainder of the original message to the reply message. The processor 228 may then sign, encrypt or sign and encrypt the reply message with the entire original message before sending, thereby providing full, end-to-end security.
Steps of a method that is an example of a first cross-component message signing approach are presented in FIG. 3 . Initially, the processor 228 , or, more accurately, a signature handling application executed on the processor 228 , detects receipt (step 302 ) of an instruction to transmit a response message and an associated signature. Such an instruction may be received from the message composition user interface application also executed on the processor 228 .
From the user's perspective, the user has specified that the response message is to be signed and the user has composed the new portion of the response message (in any order). The user may have configured the mobile communication device 100 , at some earlier time, to, by default, transmit an associated signature with each outgoing messages. The receipt (detected in step 302 ), by the signature handling application, of the instruction to transmit a response message and an associated signature may be triggered by the user opening a menu and selecting a “send” menu item.
Responsive to the detection in step 302 , the signature handling application may present (step 304 ) a dialog to warn the user that the first e-mail message will be incompletely included in the response message and giving the user choice regarding how or whether to proceed. An example of a suitable dialog is illustrated as a dialog 400 in FIG. 4 . The dialog 400 is illustrated as being displayed on the display 226 of the mobile communication device 100 .
As has been discussed above, the dialog 400 may include choices labeled “OK” and “Cancel”. Furthermore, according to an aspect of the present disclosure, the dialog 400 may include another choice, labeled “Download Original”.
It is expected that the user of the mobile communication device 100 will interact with the dialog 400 to select one of the choices. Accordingly, the signature handling application may receive (step 306 ) an indication of the user selection and determine (step 308 ) which of the choices the user has selected. Upon determining (step 308 ) that the user has selected the “Cancel” choice, the signature handling application may return (step 310 ) control to the message composition user interface.
Upon determining (step 308 ) that the user has selected the “OK” choice, the signature handling application may generate (step 312 ) a signature for the response message. To distinguish this signature from an alternative signature to be discussed hereinafter, this signature may be termed a “response” signature. The response signature is a result of encrypting a hash of the response message, where the response message includes the new portion, recently composed by the user of the mobile communication device 100 , and the initial portion of the first e-mail message (i.e., not the entire first e-mail message). The signature handling application may then arrange the transmission (step 314 ) of the response message and the response signature.
Upon determining (step 308 ) that the user has selected the “Download Original” choice, the signature handling application may obtain (step 316 ) the remainder of the first e-mail message from the wireless mail server 118 and form (step 318 ) a “new” message. The new message may be formed from the new portion, recently composed by the user of the mobile communication device 100 , and the entirety of the first e-mail message, obtained in step 316 . The signature handling application may then generate (step 320 ) a signature for the new message. To distinguish this signature from the “response” signature, this signature may be termed a “new” signature. The new signature is a result of encrypting a hash of the new message. The signature handling application may then arrange the transmission (step 322 ) of the new message and the new signature.
Additionally, the warning dialog 400 may include a checkbox labeled “Always download original”. By selecting the checkbox labeled “Always download original” and then selecting the “Download Original” choice, the user may effectively set a policy for the mobile wireless device, where the policy indicates that all future signed, and/or encrypted, messages are to include the entirety of the original received message.
As a further alternative, the dialog 400 may include a checkbox labeled “Always send truncated” (not shown). By selecting the checkbox labeled “Always send truncated” (not shown) and then selecting the “OK” choice, the user may effectively set a policy for the mobile wireless device, where the policy indicates that all future signed, and/or encrypted, messages are to include only a truncated version of the original received message.
Apart from the dialog 400 , the user may be provided with an opportunity to establish a policy through editing a policy through use of a configuration options user interface. Such a configuration options user interface may allow the user to specify a size threshold for the original message so that an original message exceeding the size threshold is not automatically downloaded in its entirety for inclusion in the new message.
Notably, the automatic downloading of the original message may be accomplished on a background thread so that the user does not have to wait for the original message to be downloaded before carrying out further activities on the mobile communication device 100 . Responsive to indicating that the message is to be sent, the user may be prompted for a signing password, but the cryptographic key, for encrypting a hash of the new message, would not be used until after the original message has been downloaded.
Notably, the original message may not always be downloaded immediately. The mobile communication device 100 makes use of a data network connection to download the original message. Accordingly, in the absence of a data network connection, the mobile communication device 100 waits until a data network connection has been established, before downloading the original message.
The first cross-component message signing approach may be adapted for message encryption instead of, or in addition to, message signing. Steps of a method that is an example of adapting the first cross-component message signing approach to encryption are presented in FIG. 5 . Initially, the processor 228 , or, more accurately, an encryption handling application executed on the processor 228 , detects receipt (step 502 ) of an instruction to transmit an encrypted response message. Such an instruction may be received from the message composition user interface application also executed on the processor 228 .
From the user's perspective, the user has specified that the response message is to be encrypted and the user has composed the new portion of the response message (in any order). The user may have configured the mobile communication device 100 , at some earlier time, to, by default, encrypt each outgoing messages. The receipt (detected in step 502 ), by the encryption handling application, of the instruction to transmit an encrypted version of the response message may be triggered by the user opening a menu and selecting a “send” menu item.
Responsive to the detection in step 502 , the encryption handling application may present (step 504 ) a dialog to warn the user that the first e-mail message will be incompletely included in the response message and giving the user choice regarding how or whether to proceed. An example of a suitable dialog is illustrated as a dialog 400 in FIG. 4 . The dialog 400 is illustrated as being displayed on the display 226 of the mobile communication device 100 .
As has been discussed above, the dialog 400 may include choices labeled “OK” and “Cancel”. Furthermore, the dialog 400 may include another choice, labeled “Download Original”.
It is expected that the user of the mobile communication device 100 will interact with the dialog 400 to select one of the choices. Accordingly, the encryption handling application may receive (step 506 ) an indication of the user selection and determine (step 508 ) which of the choices the user has selected. Upon determining (step 508 ) that the user has selected the “Cancel” choice, the encryption handling application may return (step 510 ) control to the message composition user interface.
Upon determining (step 508 ) that the user has selected the “OK” choice, the encryption handling application may encrypt (step 512 ) the response message. The encryption handling application may then arrange the transmission (step 514 ) of the encrypted response message.
Upon determining (step 508 ) that the user has selected the “Download Original” choice, the encryption handling application may obtain (step 516 ) the remainder of the first e-mail message from the wireless mail server 118 and form (step 518 ) a “new” message. The new message may be formed from the new portion, recently composed by the user of the mobile communication device 100 , and the entirety of the first e-mail message, obtained in step 516 . The encryption handling application may then encrypt (step 520 ) the new message. The encryption handling application may then arrange the transmission (step 522 ) of the encrypted new message.
A second cross-component message signing approach involves splitting the signing operation between the mobile communication device 100 and the wireless mail server 118 , thereby avoiding the downloading of the original message. Unlike the first approach, this split-signing approach cannot be considered to result in true end-to-end security, because the entire e-mail message is not signed strictly at the mobile communication device 100 . Rather, at least the new portion, recently composed by the user of the mobile communication device 100 , is signed strictly at the device, and the signing of the entire message, including the remainder not signed strictly at the device, involves the wireless mail server 118 . However, this second approach does provide a compromise between security and use of wireless channel resources, which makes it particularly suitable for signing large messages or messages with large attachments.
Steps of a method that is an example of the second approach are presented in FIG. 6 . Initially, the signature handling application detects receipt (step 602 ) of an instruction to transmit a response message and an associated signature. Such an instruction may be received from the message composition user interface application also executed on the processor 228 .
Responsive to the detection in step 602 , the signature handling application may automatically add (step 603 ) a disclaimer to the end of the response message, indicating that this point in the message marks the end of the part of the message signed at the mobile communication device 100 and/or the beginning of the part signed with the assistance of the wireless mail server 118 . For example, the disclaimer may be a line of text, such as “—end of device-signed data—”. The signature handling application may further obtain (step 604 ) a hash of the response message, where the response message includes the new portion, recently composed by the user of the mobile communication device 100 , and the initial portion of the first e-mail message (i.e., not the entire first e-mail message).
The signature handling application may then arrange the transmission (step 606 ), to the wireless mail server 118 , of a request that the wireless mail server 118 continue the hashing across the first e-mail message. Along with the request, the signature handling application may arrange the transmission of the “context” of the hash of the response message to the wireless mail server 118 . The context may be an indication of the internal state of the hashing algorithm. Such an internal state indication may allow the wireless mail server 118 to continue to obtain the hash.
Steps in an example method of participating, at the wireless mail server 118 , in the split signing operation are illustrated in FIG. 7 . Initially, the wireless mail server 118 receives (step 702 ) the hash continuation request. The wireless mail server 118 has awareness of the portion of the first e-mail message that was transmitted to the mobile communication device 100 and can therefore generate (step 704 ) a “final” hash by hashing the portion of the first e-mail message that has not been transmitted to the mobile communication device 100 , where the final hash is a hash of a “new” message. The new message includes the new portion, recently composed by the user of the mobile communication device 100 , and the entirety of the first e-mail message.
Alternatively, if the hashing algorithm is a “streaming” algorithm, the mobile communication device 100 may transmit, to the wireless mail server 118 , the current value of the hash.
Upon completing generation (step 704 ) of the hash across the first e-mail message, the wireless mail server 118 transmits (step 706 ) the final hash to the mobile communication device 100 . It should be clear that the final hash is likely to be significantly smaller than the remainder of the original message.
Upon receiving (step 608 ) the final hash from the wireless mail server 118 , the mobile communication device 100 signs (step 610 ) the final hash and arranges (step 612 ) the transmission of the response message and the encrypted hash to the wireless mail server 118 . The encrypted hash may be called the new signature.
Upon receiving (step 708 ) the response message and the new signature, the wireless mail server 118 constructs the new message by appending (step 710 ) the portion of the first e-mail message that has not been transmitted to the mobile communication device 100 to the response message and transmits (step 712 ) the new message and the new signature.
Since the second cross-component message signing approach represented by the methods of FIGS. 6 and 7 may not be considered to result in true, end-to-end security, the user may be provided with an opportunity to select the second cross-component message signing approach on a per-message basis, depending on the size of the data and/or security requirements.
In a third cross-component message signing approach, the entire hash is generated on the wireless mail server 118 . The user composes the new portion and indicates that the response message and an associated signature are to be sent.
Steps of a method that is an example of the third cross-component message signing approach are presented in FIG. 8 . Initially, the signature handling application at the mobile communication device 100 detects receipt (step 802 ) of an instruction to transmit the response message and the associated signature.
Responsive to the detection in step 802 , the signature handling application may arrange (step 804 ) transmission of the new portion to the wireless mail server 118 .
Steps in an example method of participating, at the wireless mail server 118 , in the third cross-component message signing approach are illustrated in FIG. 9 . Initially, the wireless mail server 118 receives (step 902 ) the new portion and appends the first e-mail message to the new portion, thereby forming (step 904 ) the new message. The wireless mail server 118 then generates (step 906 ) a hash of the new message. The wireless mail server 118 transmits (step 908 ) the hash to the mobile communication device 100 .
At the mobile communication device 100 , the signature handling application receives (step 806 ) the hash and signs (step 808 ) the hash to generate the new signature. The signature handling application then arranges (step 810 ) the transmission of the new signature to the wireless mail server 118 .
Upon receipt (step 910 ) of the new signature, the wireless mail server 118 transmits (step 912 ) the new message and the new signature.
The second approach to cross-component message signing exemplified in the combination of FIGS. 6 and 7 and the third approach to cross-component message signing exemplified in the combination of FIGS. 8 and 9 are suitable for message signing, but differences in the manner in which a message is signed and the manner in which a message is encrypted lead to a lack of direct applicability of these approaches to the encryption of a message.
In overview, the disclosed approaches for message signing may, with some adaptation, be extended for use in message encryption. In part, the adaptation involves the mobile communication device 100 transmitting additional, special cryptographic information to the wireless mail server 118 , thereby allowing the wireless mail server 118 to encrypt a given message.
FIG. 10 illustrates example steps of a cross-component message encryption approach. Initially, a message processing application executed on the processor 228 detects receipt (step 1002 ) of an instruction to transmit an encrypted message. Such an instruction may be received from the message composition user interface application also executed on the processor 228 .
As discussed hereinbefore, where the message to be encrypted is a message that is formed from a new portion and an initial portion of an original message, the user of the mobile communication device 100 may prefer that the entirety of the original message be included as context for the new portion. However, as also discussed hereinbefore, only the initial portion of the original message may be present at the mobile communication device 100 . Furthermore, it is noted that the original message may have been encrypted.
Responsive to detecting receipt (step 1002 ) of the instruction, the processor 228 , under control of the message processing application, may then obtain (step 1004 ) the cryptographic information that the processor 228 would typically use to encrypt a message. Such cryptographic information may include, for example, one or more session keys, including a composite message session key for encrypting the composite message, along with one or more initialization vectors corresponding to each of the one or more session keys. An initialization vector is a block of bits that allows a stream cipher or a block cipher to be executed in any of several modes of operation to produce a unique stream independent from other streams produced by the same session key. Where the original message was encrypted, the cryptographic information may also include one or more session keys, such as an original message session key for decrypting the original message.
The processor 228 , under control of the message processing application, may then arrange the transmission (step 1006 ), to the wireless mail server 118 , of the message whose transmission was requested in step 1002 . The message processing application may include, in the transmission, a request for the formation and encryption of a composite message along with the cryptographic information obtained in step 1004 .
FIG. 11 illustrates example steps in a method of participating, at the wireless mail server 118 , in the cross-component message encryption approach of FIG. 10 . Initially, the wireless mail server 118 receives (step 1102 ) the new message, encryption request and associated cryptographic information.
In the case wherein the original message was encrypted, the wireless mail server 118 may then decrypt (step 1104 ) the original message using an appropriate portion of the received cryptographic information.
The wireless mail server 118 may then create (step 1106 ) a composite message by appending the original message to the new message. Both the new message and the original message may include a body portion and one or more attachments. Accordingly, while creating (step 1106 ) the composite message, the wireless mail server 118 may append a body portion of the original message to a body portion of the new message and add attachments from the new message to the composite message and add attachments from the original message to the composite message.
Upon completing creation (step 1106 ) of the composite message, the wireless mail server 118 encrypts (step 1108 ) the composite message using an appropriate portion of the cryptographic information received in step 1102 . In conjunction with encrypting (step 1108 ) the composite message, the wireless mail server 118 may wrap the composite message in an appropriate encoding. Such appropriate encoding may, for example, comprise encoding using a standard known as Secure/Multipurpose Internet Mail Extensions (S/MIME), which is a known standard for public key encryption and signing of data. Alternatively, such appropriate encoding may, for example, comprise encoding using a standard known as Pretty Good Privacy (PGP), which is a known data encryption and decryption computer standard that provides cryptographic privacy and authentication for data communication.
In an alternate implementation, rather than receiving the composite message session key from the mobile communication device 100 , the wireless mail server 118 generates the composite message session key and the corresponding initialization vector. This implementation may also involve sending the composite message session key to the mobile communication device 100 , so that the mobile communication device 100 may decrypt the sent composite message, if necessary.
When the composite message has been encrypted and wrapped, the wireless mail server 118 may transmit (step 1110 ) the encrypted composite message toward recipients specified in a destination field of the new message.
FIG. 12 illustrates example steps of a cross-component message encryption approach distinct from the cross-component message encryption approach of FIGS. 10 and 11 . Initially, a message processing application executed on the processor 228 detects receipt (step 1202 ) of an instruction to transmit an encrypted and signed message. Such an instruction may be received from the message composition user interface application also executed on the processor 228 .
As discussed hereinbefore, where the message to be encrypted and signed is a message that is formed from a new portion and an initial portion of an original message, the user of the mobile communication device 100 may prefer that the entirety of the original message be included as context for the new portion. However, as also discussed hereinbefore, often only the initial portion of the original message may be present at the mobile communication device 100 . Furthermore, it is noted that the original message may have been encrypted.
Responsive to detecting (step 1202 ) receipt of the instruction, the processor 228 , under control of the message processing application, may then obtain (step 1204 ) the cryptographic information that the processor 228 would typically use to encrypt a message. Such cryptographic information may include, for example, one or more session keys, including a composite message session key for encrypting the composite message, along with one or more initialization vectors corresponding to each of the one or more session keys. Where the original message was encrypted, the cryptographic information may also include one or more session keys, including an original message session key for decrypting the original message.
The processor 228 , under control of the message processing application, may then arrange the transmission (step 1206 ), to the wireless mail server 118 , of the message whose transmission was requested in step 1002 . The message processing application may include, in the transmission, the cryptographic information obtained in step 1004 and a request for a hash of the composite message to be created, at the wireless mail server 118 , from the new message and the original message.
FIG. 13 illustrates example steps in a method of participating, at the wireless mail server 118 , in the cross-component message encryption approach of FIG. 12 . Initially, the wireless mail server 118 receives (step 1302 ) the new message, associated cryptographic information and hash request.
In the case wherein the original message was encrypted, the wireless mail server 118 may then decrypt (step 1304 ) the original message using an appropriate portion of the received cryptographic information.
The wireless mail server 118 may then create (step 1306 ) a composite message by appending the original message to the new message. Both the new message and the original message may include a body portion and one or more attachments. Accordingly, while creating (step 1306 ) the composite message, the wireless mail server 118 may append a body portion of the original message to a body portion of the new message and add attachments from the new message to the composite message and add attachments from the original message to the composite message.
Upon completing creation (step 1306 ) of the composite message, the wireless mail server 118 generates (step 1308 ) a hash of the composite message and transmits (step 1310 ) the hash to the mobile communication device 100 with a hash signing request, specifying that the hash is to be signed.
Upon receiving (step 1208 ) the hash signing request from the wireless mail server 118 , the mobile communication device 100 obtains (step 1210 ) a private key specific to a user of the mobile communication device 100 . Obtaining (step 1210 ) the private key may, for example, involve prompting the user for a password to allow the processor 228 access to a key store, in memory of the mobile communication device 100 , from which the processor 228 may obtain the private key.
Upon obtaining (step 1210 ) the private key, the processor 228 may sign (step 1212 ) the hash to form a signature for the composite message. The processor 228 may then arrange (step 1214 ) the transmission of the signature to the wireless mail server 118 .
The wireless mail server 118 receives (step 1312 ) the signature and adds (step 1314 ) the signature to the composite message.
Upon adding (step 1314 ) the signature to the composite message, the wireless mail server 118 may encrypt (step 1316 ) the signed composite message using an appropriate portion of the cryptographic information received in step 1302 . In conjunction with encrypting (step 1316 ) the signed composite message, the wireless mail server 118 may wrap the composite message in an appropriate encoding as discussed hereinbefore.
When the signed composite message has been encrypted and wrapped, the wireless mail server 118 may transmit (step 1318 ) the encrypted and signed composite message toward recipients specified in a destination field of the new message.
The above-described embodiments of the present application are intended to be examples only. Alterations, modifications and variations may be effected to the particular embodiments by those skilled in the art without departing from the scope of the application, which is defined by the claims appended hereto. | Often, for reasons of wireless bandwidth conservation, incomplete messages are provided to wireless messaging devices. Employing cryptography, for secrecy or authentication purposes, when including a received message that has been incompletely received can lead to lack of context on the receiver's end. By automatically obtaining the entirety of the message to be included, an outgoing message that includes the received message can be processed in a manner that securely and accurately represents the intended outgoing message. Alternatively, a server can assemble a composite message from a new message and an original message and, in cooperation with a wireless messaging device, encrypt and sign the composite message. Conveniently, security considerations are maintained even in view of bandwidth optimization measures. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a copper-based sintered contact component which has exceptional resistance to wear and fusion and can stably retain a comparatively high coefficient of friction, say, about 0.4 to 0.6, under dry contact conditions. The component can stably exhibit a friction coefficient of more than 0.1 when placed in lubricating oil. Further, the component is very unlikely to attack counterpart material and has high strength, high toughness, and high hardness. Therefore, it is applicable for use in the art of contact components, such as clutches and brakes of both dry and wet types.
2. Description of the Prior Art
Recently, for use as materials for friction clutches and brakes to be used under dry conditions, bronze-based sintered alloys have been developed which can replace asbestos-based friction materials. For example, Japanese Patent Application Laid-Open No. 58 -126948 describes a "dry sintered friction material" which comprises a bronze-based sintered alloy and hard particulate matter added thereto to provide higher coefficient of friction.
However, such sintered material has no reaction layer between the hard particulate matter dispersed in the alloy and the matrix, but involves gaps therebetween. As such, during friction contact under high-speed, high-load contact conditions, hard particles may come off the matrix, and this makes it impracticable to expect any high friction coefficient to be stably exhibited. Another problem is that fusion may occur relative to counterpart material starting from the point at which such particle fall-off has occurred. A further problem is come-off particle bite and attack against counterpart material.
Additionally, in the aspect of mechanical characteristics, the sintered material as an abrasion material involves the problem that aforesaid gaps will deteriorate the mechanical characteristics of the material, such as strength, toughness and hardness. Another problem is that the dispersed hard particles are diametrically large-sized on the order of 30 to 80 μm, which fact, as a source of fracture, will induce deterioration in strength and toughness.
Conventional wet friction materials which have generally been used are porous paper-made friction materials and/or carbon sintered materials. As an example of the first mentioned type, reference may be made to Japanese Patent Application Laid-Open No. 6-25653 which describes a "paper friction material" composed principally of a thermosetting resin, such as phenolic resin, and friction adjustors, such as graphite powder and organic dust, with organic fibers and carbon fibers used as reinforcements. For the latter mentioned type, reference may be made to Japanese Patent Application Laid-Open No. 4-76086 entitled "Wet Friction Material" in which is proposed a carbon fiber-reinforced carbon sintered body produced by sintering a composite composed of uncarbonized carbonaceous fibers and carbonaceous powder. Materials of the both types are elastically deformable, and this enables any biased engagement force to be absorbed on the friction material side.
Generally, however, such friction material, when held in oil, has a small coefficient of friction only on the order of 0.1 to 0.15. Therefore, in order that a clutch, for example, may provide any sufficient transmission torque, it is necessary that a friction material having larger diameter and larger surface area be used. As a result, the current need for size/weight reduction cannot be met. Further, the paper friction material lacks heat resistance. During friction contact under high temperature conditions, therefore, such friction material may become damaged due to frictional wear and may also be subject to deterioration in its characteristics, which will lower the friction coefficient of the friction material further.
In an attempt to overcome these problems, Japanese Patent Application Laid-Open No. 4-76086, entitled "Friction Material", proposes a friction material such that a pseudoalloy spray coating comprised of two kinds of metal is formed on the contact surface of a friction material (glass fiber and/or rubber binder), whereby the friction material can have a high friction coefficient of the order of more than 0.25.
According to this technique, however, the process of spray coating is required in addition to the placement of the friction material on a substrate. This poses a problem because it adds to costs and process complexity. Further, because of the fact that thermal spraying is required, it is impracticable to expect any good productivity with the method.
Conventionally, bronze-based (copper-tin) sintered alloys have been used as oilless bearing materials. Sintered alloys of this type have high abrasion resistance and high fusion resistance. Therefore, it may be expected that a friction material comprised of such a sintered alloy with hard particles loaded and dispersed therein would exhibit a high coefficient of friction without being liable to any damage due to friction.
As already stated, however, it has been found that since hard particles loaded are present in grain boundaries of the matrix bronze powder, during friction contact, such particles would fall off and even attack the counterpart material, and that the sintered material per se would be subject to fusion and frictional wear. Another problem is that since bearing-type sintered alloys have many vacancies dispersed in their interior, in a high slide velocity range in excess of 20 m/sec, for example, lubricating oil present within the sintered alloy flows out of the interior so that an oil reservoir may be formed in a vacancy in the contact surface. As a consequence, a thick oil film is formed between the contact surface of the friction material and the counterpart material, with the result that the friction coefficient of the friction material is lowered to a 0.01-0.02 level.
SUMMARY OF THE INVENTION
In order to overcome the foregoing problems, the present invention is directed to economically manufacturing a sintered component comprising hard particles admixed with and finely and uniformly dispersed in a primary particle of a matrix to provide improved friction coefficient under dry and wet contact conditions, and in which the dispersed hard particles are inhibited from coming off the Cu--Sn alloy matrix during contact movement so that the sintered component is possessed of good friction contact characteristics and improved mechanical properties.
Accordingly, in order to solve the foregoing problems, the present inventors conducted extensive experiments and studies and, as a result, they developed a high-strength sintered contact component which can stably retain high friction coefficient under dry and wet friction contact conditions and is, therefore, free of the possibility of attacking counterpart material, and which is less liable to wear due to friction and unlikely to involve fusion relative to the counterpart material.
Specifically, according to the invention, alloy compositions of sintered contact components and method of making the same are as stated below.
(1) A sintered contact component comprising a copper-based sintered alloy having a structure such that 15 to 25 wt % of a hard particulate material having a maximum particle diameter of not more than 15 μm and a mean particle diameter of not more than 5 μm is uniformly dispersed in former powder particles within an alloy matrix, the sintered contact component having a friction coefficient of not less than 0.4 when in contact with steel material under dry ambient conditions and a friction coefficient of not less than 0.1 when in contact with steel material in lubricating oil.
(2) A sintered contact component as set forth in (1) above, wherein when the component comes into contact with steel material under dry ambient conditions, the difference between its coefficient of static friction and its coefficient of dynamic friction is not more than 0.1.
(3) A sintered contact component as set forth in (1) above, wherein the copper-based sintered alloy comprises vacancies having a mean diameter of not more than 30 μm which are uniformly dispersed within the alloy in a range of from 1 vol % to 30 vol %.
(4) A sintered contact component as set forth in (1) above, wherein the matrix of the copper-based sintered alloy comprises 3 to 20 wt % of Sn, with the balance being made up substantially of Cu and unavoidable impurities.
(5) A sintered contact component as set forth in (1) above, wherein the hard particulate material is composed of at least one, or more than one, of iron-based intermetallic compounds including FeMo, FeCr, FeTi, FeW, and FeB.
(6) A sintered contact component as set forth in (1) above, wherein the copper-based sintered alloy contains not more than 3 wt % of a solid lubricating material as required.
(7) A sintered contact component as set forth in (6) above, wherein the solid lubricating material is composed of at least one, or more than one, of spherical graphite, MoS 2 , CaF 2 and BN.
(8) A sintered contact component as set forth in (1) above, wherein the copper-based sintered alloy contains not more than 15 wt % of natural scaly graphite powder, or expanded graphite powder that is converted from natural scaly graphite powder by expanding the same in the direction of thickness, as required.
(9) A sintered contact component as set forth in (1) above, wherein the copper-based sintered alloy is made from a hard-particle dispersed composite copper alloy powder comprising a mixture powder consisting of a Cu--Sn alloy powder containing 3 to 20 wt % of Sn, with the balance being substantially made up of Cu and unavoidable impurities, and 15 to 25 wt % of a hard particulate material, the mixture powder being subjected to the process of mixing and milling by one of the mechanical alloying, mechanical grinding, and pulverizing techniques so that the hard particulate material is pulverized to a maximum particle size of not more than 15 μm and a mean particle size of 5 μm and is uniformly dispersed in the Cu--Sn alloy matrix.
(10) A sintered contact component as set forth in (1) or (9) above, wherein the copper-based sintered alloy is made from a mixture powder consisting of the hard particle-dispersed composite copper alloy powder and not more than 3 wt % of a solid lubricating material.
(11) A sintered contact component as set forth in (9) above, wherein the copper-based sintered alloy is made from the hard-particle dispersed composite copper alloy powder and, in combination therewith, not more than 15 wt % of natural scaly graphite powder, or expanded graphite powder that is converted from natural scaly graphite powder by expanding the same in the direction of thickness.
(12) A sintered contact component as set forth in (1) above, wherein the copper-based sintered alloy is made from a hard-particle dispersed composite copper alloy powder comprising a mixture powder consisting of 3 to 20 wt % of Sn, and 15 to 25 wt % of hard particulate material, with the balance being substantially made up of Cu and unavoidable impurities, the mixture powder being subjected to the process of mixing and milling by one of the mechanical alloying, mechanical grinding, and pulverizing techniques so that the hard particulate material is pulverized to a maximum particle size of not more than 15 μm and a mean particle size of 5 μm and is uniformly dispersed in the Cu--Sn alloy matrix.
(13) A sintered contact component as set forth in (1) or (12) above, wherein the copper-based sintered alloy is made from a mixture powder comprising the hard-particle dispersed composite copper alloy powder and not more than 3 wt % of solid lubricating material.
(14) A sintered contact component as set forth in (12) above, wherein the copper-based sintered alloy is made from a mixture powder comprising the hard-particle dispersed composite copper alloy powder and not more than 15 wt % of natural scaly graphite particles, or expanded graphite powder that is converted from natural scaly graphite particles by expanding the same in the direction of thickness.
Next, the reasons why the alloy compositions and the proportion of vacancies in the foregoing copper-based sintered alloys are set as above stated will be explained.
(1) Sn
Sn, together with Cu, forms the matrix of the alloy and can enhance high temperature strength and toughness of the alloy. It also can improve fusion resistance of the alloy relative to counterpart material at elevated temperatures. If the proportion of Sn is less than 3 wt %, no such effect can be obtained, while if Sn is added in excess of 20 wt %, precipitation of a hard and brittle phase will occur, resulting in deterioration in strength and toughness. Therefore, the proportion of Sn is set within the range of 3 to 20 wt %.
(2) Hard particles (iron-based intermetallic compound)
Hard particles are finely and uniformly dispersed in a primary particle of the matrix of the sintered alloy and can inhibit adhesion of the alloy with counterpart material under dry and wet friction conditions at ordinary and elevated temperatures, thereby improving the fusion resistance of the sintered alloy. Also, they come in direct contact with counterpart material surface to provide increased coefficient of friction, thereby enhancing the wear resistance of the sintered alloy.
The particle size and proportion of such particulate material will have the following effects. If the proportion of hard particles is less than 15 wt %, no improvement in wear resistance can be obtained. If the maximum particle size is greater than 15 μm or the mean particle size is greater than 5 μm, or if the proportion of hard particles is more than 25 wt %, the hard particles are likely to become a starting point at which cracking will occur, thus resulting in deterioration in the strength and toughness of the sintered material. Also, from the view point of counterpart attack possibility, addition of hard particles at such particle size and quantity levels is undesirable because it results in considerable wear being caused to the counterpart material.
When the sintered material contains 15 to 25 wt % of hard particles having a particle size range of up to 15 μm, with a mean particle size of not more than 5 μm, which are finely and uniformly dispersed in a primary particle of the matrix, the sintered material can have good stability in friction coefficient. Preferably, therefore, the hard particles have a particle size range of up to 15 μm maximum, with a mean particle size of not more than 5 μm, and the total hard particle content is 15 to 25 wt %.
The iron-based intermetallic compound is preferably comprised of at least one, or more than one, of FeMo, FeCr, FeTi, FeW, and FeB. Besides iron-based intermetallic compounds, metallic oxides, such as Al 2 O 3 , SiO 2 , and ZrO 2 , and ceramics, such as SiC and AlN, may be effective for friction coefficient improvement, but particles of these are less machinable as compared with particles of iron-based intermetallic compounds, which fact poses a problem from the view point of economy. Therefore, use of iron-based intermetallic compounds is preferred for purposes of the contact component of the invention.
However, if such iron-based intermetallic compound comes off the matrix during contact movement, there will develop particle transfer and/or adhesion relative to counterpart material starting from the location of such particle separation. Another problem is that any separated particle may bite into the counterpart material to cause wear and/or damage to the counterpart material. Therefore, in order to avoid any such occurrence so as to ensure constantly stable, high coefficient of friction, it is required that particulate intermetallic compound be uniformly dispersed in a primary particle of the matrix and particles thereof be inhibited from coming off the matrix.
A specific method therefor is as follows. That is, the intermetallic compound is mechanically alloyed with a Cu--Sn-based alloy powder or a powder mixture of Su and Sn, whereby the intermetallic compound as ground to a particle size of up to 15 μm, maximum, with a mean particle size of 5 μm, can be finely and uniformly dispersed in the Cu--Sn-based alloy particles. After compacting, molding and sintering of the powder, a reaction layer is formed at the interface between the Cu--Sn-based alloy of the matrix and the intermetallic compound, whereby the intermetallic compound can be firmly immobilized in the matrix. Specifically, it has been found that only by employing mechanical powder mixing/grinding techniques, such as mechanical alloying, mechanical grinding, and pelletizing, is it possible to obtain a Cu--Sn-based alloy powder such that intermetallic compound particles are finely and uniformly dispersed in a particulate mass of the Cu--Sn-based alloy powder so that they are unlikely to come off sintered matrix during contact movement.
It is noted that such mechanical powder mixing is carried out in dry process, and not in wet process as in conventional ball milling or mixing. In some cases, stearic acid or alcohol, as a PCA (process control agent), may be added in a small quantity in order to prevent excessive agglomeration. For carrying out the process, an ATTORITOR unit or ball mill may be suitably employed. The former is suited for high-speed processing because it exhibits high grinding efficiency. The latter involves prolonged grinding operation but permits easy atmosphere control and has a relatively good advantage in respect of economy, only if the arrangement for input energy is properly designed.
(3) Solid lubricating ingredient
The solid lubricating ingredient is effective in correcting the counterpart attack behavior of a sintered contact component under dry friction conditions and also in moderately stabilizing a comparatively high coefficient of the order of about 0.4 to 0.6 under dry contact conditions at elevated temperatures, whereby surface lubricity between contact surfaces can be enhanced, and whereby the problem of squeaks, vibrations and noisiness upon contact can be reasonably overcome.
If sliding velocity becomes higher under wet contact conditions, vacancies existing on the contact surface provide an wedging effect so that lubricating oil is taken into the vacancies to form a lubricating film in the contact interface between the sintered friction material and the counterpart steel material.
In particular, when the contact component is used at a high velocity level of more than 20 m, the component may be subject to variations/downward changes in friction coefficient. As a solution to such a problem, it is arranged that the sintered friction material contains solid lubricating material and this provides for improvement in the stability of friction coefficient relative to slide velocity.
In Cu--Sn-based sintered alloys, solid lubricating ingredients having these characteristic features are graphite, MoS 2 , CaF 2 , and BN which economically involve fewer problems. As another lubricating ingredient, Pb, for example, is used in Cu--Sn alloy-made bearings, but use of this material in a contact component involves falloff possibilities during contact movement because the material does not function to produce a compound in association with the matrix and is present in the form of fine particles in dendrite arm spacings of α phase. For effective use as such ingredient, at least one or more of graphite, MoS 2 , CaF 2 , and BN may be loaded in the amount of not more than 3 wt %. Use of the ingredient in excess of 3 wt % is undesirable because it would result in considerable deterioration in the strength and toughness of the sintered body.
However, the present inventors made attempts to use natural scaly graphite powder, a graphite powder material which is characteristically different from spheroidal graphite powder conventionally used in powder metallurgy, and/or expanded graphite powder as obtained by expanding the natural scaly graphite powder in the direction of thickness.
Specifically, scaly graphite powder, as compared with conventional spheroidal graphite powder, is characteristically advantageous in (1) moldability/compressibility and (2) lubricating performance. That is, whereas use of conventional spheroidal graphite powder in excess of 3 wt % of the total will result in some deterioration in the mechanical characteristics of the sintered body, scaly graphite powder or expanded graphite powder, if it is loaded up to 15 wt %, will not induce any such decrease in the mechanical characteristics of the sintered body. Additionally, because of its good lubricating performance, scaly graphite powder can more effectively inhibit such troubles as noisiness, vibrations and squeaks which may occur during contact movement as earlier mentioned. Also, scaly graphite powder helps improve the conformability of the contact component with the counterpart material at an initial contact stage and better stabilize the friction coefficient of the contact component.
Furthermore, where such graphite powder is dispersed in a sintered body, good compressibility of the graphite powder can be advantageously utilized for compressibility improvement of the sintered body itself when subjected to pressure, so that local contact with the contact surface of the counterpart material can be inhibited and thus full contact can be allowed, whereby stable friction contact performance may be assured.
Therefore, a sintered body fabricated by mixing and compacting a hard-particle dispersed composite copper alloy powder, a main feature of the invention, and aforesaid scaly graphite powder or expanded graphite powder, or both of them, can exhibit more improved mechanical properties and friction contact properties; more particularly it can exhibit a stable coefficient of friction continually from an initial stage of contact movement.
(4) Vacancy
Vacancies are of a size of not more than 30 μm and are uniformly distributed over the friction contact surface of the sintered alloy, so that they are subject to deformation upon surface contact and will produce wedging effect to allow air flow into the vacancies during contact movement, which in turn will produce buoyancy. Therefore, under dry contact conditions, vacancies provide good fusion resistance and improved adaptability relative to counterpart component. Under wet contact conditions, aforesaid self-lubricating effect permits an oil reservoir (oil film) to be formed in vacancies, whereby improved fusion resistance can be obtained.
A vacancy size greater than 30 μm may be a cause of cracking and results in considerable decrease in the strength and toughness of the sintered product. If the volume of vacancies is less than 1 vol %, the above mentioned advantage is unlikely to be obtained. If vacancies are distributed in excess of 30 vol %, the strength and toughness of the sintered alloy may be lowered. If vacancies are unevenly distributed, the conformability of the sintered alloy relative to counterpart material will be locally reduced; therefore, no stable friction coefficient can be obtained and, in addition, fusion with the counterpart material is likely to occur. In the sintered contact component of the invention, therefore, it is desirable that vacancies should have a size of not more than 30 μm and be uniformly distributed within a range of 1 to 30 vol % in the contact component. For the purpose of the present invention, above specified vacancy size and volume can be attained by controlling the working pressure during the process of powder pressing and molding.
Sintered contact components having the above mentioned alloy composition and made according to the foregoing method have mechanical properties, such as strength, toughness and hardness, and also friction resistance and self-lubricating property, which are sufficient to qualify such contact component for use singly as structural material without reinforcement. Under dry friction contact conditions, conventional Cu--Sn-based alloys, under dry friction contact conditions, have a friction coefficient range of about 0.2 to 0.3 during an initial contact period and, under wet friction contact conditions, have a friction coefficient range of 0.02 to 0.05. As friction progresses, the friction coefficient of such alloy tends to change upward and finally the sintered alloy goes into fusion with counterpart material or the alloy itself gets worn.
In contrast to this, the sintered contact component of the invention can stably retain a comparatively high friction coefficient, say about 0.4 to 0.6 under dry contact conditions and about 0.1 or more under wet contact conditions. Furthermore, it will never attack the counterpart material, nor will it be liable to fusion with or friction wear/damage relative to the counterpart.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart showing the process of making sintered contact components according to the present invention;
FIG. 2 is an explanatory view showing how dry friction tests are carried out with respect to sintered contact components of the invention.
FIG. 3 is an explanatory view showing how wet friction tests are carried out with respect to sintered contact components of the invention; and
FIG. 4 is a graph showing changes in coefficient of kinetic friction in dry friction tests.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will now be explained with reference to the accompanying drawings.
Alloy compositions of sintered contact components according to the invention and of comparative materials are shown in Table 1. Mechanical characteristics of the sintered contact components, and abrasion test results (friction coefficient and quantities of wear with respect to sintered materials and counterpart material SS41) are shown in Table 2.
Sample powders were molded and sintered under manufacturing conditions according to the respective processes shown in FIG. 1. (In the figure, "Mechanical grinding/mixing" means mechanical alloying, mechanical mixing, and pelletizing.) Abrasion tests were carried out employing the dry abrasion tester shown in FIG. 2. For friction coefficient values, measurements were made at time intervals of one minute beginning from the start of testing, and stable measurements are shown in the table.
In the table, Nos. 1 through 17 represent sintered components of the invention, while Nos. 18 through 28 represent comparative materials. It is noted that only vacancy measurements are expressed in vol % and all other measurements are expressed in wt %. Symbols A, B, C and D for solid lubricating ingredients signify respectively: A for graphite, B for MoS 2 , C for CaF 2 , and D for BN.
In Table 1, Remarks *1, *2 and *3 mean as follows:
*1) An alloy produced by subjecting a mixed powder to mechanical grinding/mixing according to the process (a) in FIG. 1, with grinding conditions being changed so that the dispersed hard particles or Fe-based intermetallic compound particles were ground to a mean particle size of 15 μm, and by molding and sintering the so treated mixture.
*2) An alloy produced by subjecting a mixed powder to mechanical grinding/mixing according to the process (a) in FIG. 1, with surface pressure conditions during the stage of powder molding being changed so that vacancies distributed in the powder molded product were sized 45 μm mean, and by sintering the so treated mixture.
*3) An alloy produced by simply mixing various powders having prescribed compositions without subjecting them to the process of mechanical grinding/mixing, such as mechanical alloying, mechanical mixing, or pelletizing, and then sintering the mixture.
TABLE 1__________________________________________________________________________ Hard Particle Solid Lubricant VacancyNo. Process Sn FeMo FeCr FeW FeTi FeB Total A B C D Total vol % Cu Remark__________________________________________________________________________1 a 10 20 0 0 0 0 20 1 0 0 0 1 18 Balance2 a 10 0 20 0 0 0 20 1 0 0 0 1 18 Balance3 a 12 0 0 20 0 0 20 1 0 0 0 1 20 Balance4 a 10 0 0 0 20 0 20 1 0 0 0 1 20 Balance5 a 12 0 0 0 0 20 20 1 0 0 0 1 20 Balance6 b 10 15 0 0 0 0 15 1 0 0 0 1 15 Balance7 c 10 25 0 0 0 0 25 1 0 0 0 1 25 Balance8 b 10 10 10 0 0 0 20 1 0 0 0 1 25 Balance9 c 5 0 0 0 20 0 20 1 0 0 0 1 20 Balance10 d 15 20 0 0 0 0 20 0.5 0 0 0 0.5 20 Balance11 d 10 20 0 0 0 0 20 2 0 0 0 2 18 Balance12 a 12 20 0 0 0 0 20 3 0 0 0 3 5 Balance13 a 10 0 20 0 0 0 20 0 1 0 0 1 20 Balance14 a 10 20 0 0 0 0 20 0 1 0 1 2 17 Balance15 b 10 10 10 0 0 0 20 0 0 1 0 1 20 Balance16 c 10 20 0 0 0 0 20 0 0 1 1 2 14 Balance17 a 12 20 0 0 0 0 20 0.5 0.5 0 0 1 25 Balance18 a 2 20 0 0 0 0 20 1 0 0 0 1 10 Balance19 a 35 20 0 0 0 0 20 1 0 0 0 1 10 Balance20 a 10 10 0 0 0 0 10 1 0 0 0 1 10 Balance21 a 10 15 0 15 0 0 30 1 0 0 0 1 10 Balance22 b 10 20 0 0 0 0 20 0 0 0 0 0 10 Balance23 b 10 20 0 0 0 0 20 4 0 0 0 4 10 Balance24 a 10 20 0 0 0 0 20 1 0 0 0 1 0 Balance25 a 10 20 0 0 0 0 20 1 0 0 0 1 35 Balance26 a 10 20 0 0 0 0 20 1 0 0 0 1 20 Balance *127 a 10 20 0 0 0 0 20 1 0 0 0 1 20 Balance *228 -- 10 20 0 0 0 0 20 1 0 0 0 1 20 Balance *3__________________________________________________________________________ (Sample of Invention: Nos. 1-17; Comprative Samples: Nos. 18-28)
TABLE 2__________________________________________________________________________Mechanical Property Friction Contact Characteristic Breaking Wear.sup.2) mgSample UTS Elongation strength Sintered DamageNo. MPa % MPa μ value Δ μ.sup.1) material SS41 Condition__________________________________________________________________________1 220 7.5 360 0.52 0.05 6 2 No damage2 222 6.8 351 0.55 0.06 7 3 No damage3 216 7.2 348 0.54 0.05 5 4 No damage4 214 7.0 345 0.55 0.05 6 3 No damage5 218 7.1 358 0.57 0.06 7 4 No damage6 245 6.5 388 0.50 0.03 7 2 No damage7 204 7.7 340 0.60 0.07 6 3 No damage8 207 7.0 336 0.57 0.05 8 3 No damage9 216 7.0 357 0.53 0.04 5 3 No damage10 211 6.6 344 0.60 0.08 4 4 No damage11 223 6.6 353 0.51 0.04 5 5 No damage12 273 9.9 402 0.45 0.02 5 4 No damage13 220 6.8 354 0.55 0.05 7 6 No damage14 226 6.6 355 0.51 0.04 5 4 No damage15 218 6.7 354 0.56 0.06 6 3 No damage16 240 7.4 384 0.48 0.03 6 5 No damage17 208 6.6 333 0.50 0.04 5 6 No damage18 112 8.8 167 0.72 0.06 2 × 10.sup.3 5 Sintered material worn19 270 1.6 410 0.77 0.09 11 68 SS41 attacked20 240 7.8 385 0.28 0.04 8 6 No damage21 165 1.9 197 0.64 0.14 12 105 SS41 attacked22 276 9.6 415 0.86 0.06 8 × 10.sup.3 -6 × 10.sup.3 Fusion23 126 2.2 171 0.30 0.01 9 6 No damage24 291 10.6 432 0.88 0.18 8 × 10.sup.3 -5 × 10.sup.3 Fusion25 94 1.1 101 0.43 0.04 2 × 10.sup.3 6 Sintered material worn26 114 2.0 133 0.66 0.18 11 95 SS41 attacked27 105 1.6 124 0.51 0.05 3 × 10.sup.3 5 Sintered material worn28 123 2.4 165 0.28 0.26 4 × 10.sup.3 -3 × 10.sup.3 Fusion__________________________________________________________________________ .sup.1) Δ μ indicates the difference between static coefficients of friction and dynamic coefficient of friction. .sup.2) Minus (-) indicates gain due to deposition.
Material Nos. 1 through 17 represent alloys according to the invention, and their mechanical characteristics and the results of friction tests with them are satisfactory as shown in Table 2.
Test results with respect to comparative materials are as stated below.
18: Matrix strength is insufficient because the Sn content is as small as 2%, so that the friction material is worn away, which results in an increase in μ value.
19: The Sn content is as large as 35%, so that the matrix becomes so much hardened as to cause the friction material to attack the counterpart material, which results in an increase in μ value.
20: The hard particle content is as small as 10 wt so that any sufficient level of μ value cannot be attained.
21: The hard particle content is so large on the order of 30 wt %, so that any sufficient level of μ value cannot be attained.
22: Absence of solid lubricant causes lack of lubrication, which results in fusion with the counterpart material.
23: The proportion of solid lubricant is so large on the order of 4%, resulting in lowered strength and toughness characteristics.
24: Non-presence of vacancy results in reduced fusion resistance and occurrence of fusion with the counterpart material.
25. The presence of vacancies in such a large volume as 35% causes lack of strength and toughness, resulting in friction material wear.
26. Mean particle size of hard particles is as large as 15 μm, which results in decreased strength and toughness, and also in the trouble of the counterpart material being attacked.
27. Vacancy size is as large as 45 μm mean, which results in strength and toughness insufficiency and friction material wear.
28. Since respective powders having specified ingredients are simply mixed without being subjected to mechanical grinding/mixing, followed by sintering, no reaction layer is formed between the hard particles and the matrix. This, coupled with the fact that there are present very coarse hard particles, causes hard particles to come off the matrix during contact movement, resulting in the trouble of fusion with the counterpart material and also in decreased strength and toughness with respect to the sintered alloy.
Friction tests were carried out with respect to sintered contact materials of the present invention and comparative materials which were fabricated according to the individual alloy compositions and manufacturing methods as shown in Table 1. Results of the tests (friction coefficient relative to slide velocity, and wear of friction material and that of counterpart material S35C) are shown in Table 3. Abrasion tests were carried out employing the wet abrasion tester shown in FIG. 3. For friction coefficient values, measurements were made at time intervals of one minute beginning from the start of testing, and stable measurements are shown in the table.
TABLE 3__________________________________________________________________________ Friction Contact Characteristic Wear.sup.1) mgSample Table 1 Slide speed SinteredNo. Sample No. m/sec μ value material S35C Damage Condition__________________________________________________________________________1 1 0.1 0.37 3 1 No damage2 1 1 0.36 3 1 No damage3 1 5 0.36 3 1 No damage4 1 10 0.35 4 1 No damage5 1 20 0.33 4 1 No damage6 1 40 0.33 4 2 No damage7 8 5 0.38 3 0 No damage8 8 20 0.34 3 1 No damage9 16 8 0.36 2 1 No damage10 16 30 0.34 3 2 No damage11 18 5 0.71 6 × 10.sup.2 -5 × 10.sup.2 Sintered material: wear/fusion12 19 10 0.68 44 4 × 10.sup.2 S35C attacked/penetrated13 20 5 0.15 2 1 No damage14 21 5 0.68 26 3 × 10.sup.2 S35C attacked15 22 40 0.1˜0.3 8 5 Friction coefficient fluctuate16 24 5 0.71 4 × 10.sup.2 -2 × 10.sup.2 Fusion17 28 5 0.72 7 × 10.sup.3 -5 × 10.sup.3 Sintered material: wear/fusion18 28 10 0.68 5 × 10.sup.3 -2 × 10.sup.2 Sintered material: wear/fusion__________________________________________________________________________ .sup.1) Minus (-) indicates gain due to deposition
In the table, Nos. 1 through 10 represent sintered components of the invention, while Nos. 11 through 18 represent comparative components. Friction test results with respect to alloy Nos. 1 through 10 are satisfactory as shown in Table 3.
Test results with respect to comparative materials are as follows:
11: Matrix strength is insufficient because the Sn content is small or only 2%, so that the friction material is worn and penetrated, which results in an increase in μ value.
12: The Sn content is as large as 35%, so that the matrix becomes so much hardened that the counterpart S35C material is attacked and penetrated, which results in an increase in μ value.
13: The proportion of hard particles is small or only 10 wt %; therefore, no sufficient μ value can be obtained.
14: The hard particle content is large on the order of 30 wt %, so that hard particles attack the counterpart material and penetrate thereinto, which results in increased μ value.
15: Since the sintered component has no solid lubricant content, contact movement under high speed condition results in friction coefficient variations.
16: Because of 0% vacancy, no oil film (oil reservoir) is formed and fusion with the counterpart material is unavoidable.
17: Since respective powders having specified ingredients are simply mixed without being subjected to mechanical grinding/mixing, followed by sintering, no reaction layer is formed between the hard particles and the matrix. This, coupled with the fact that there are present very coarse hard particles, causes hard particles to come off the matrix during contact movement, so that fusion with the counterpart material occurs, which results in an increase in μ value.
18: Since respective powders having specified ingredients are simply mixed without being subjected to mechanical grinding/mixing, followed by sintering, no reaction layer is formed between the hard particles and the matrix. This, coupled with the fact that there are present very coarse hard particles, causes hard particles to come off the matrix during contact movement, so that fusion with the counterpart material occurs, which results in an increase in μ value.
Alloy compositions of sintered contact components according to the invention and of comparative materials are shown in Table 4. Mechanical characteristics of the sintered contact components, and abrasion test results (friction coefficient and quantities of wear with respect to sintered materials and counterpart material SS41) are shown in Table 5.
Sample powders were molded and sintered under manufacturing conditions according to the respective processes shown in FIG. 1. (In the figure, "Mechanical grinding/mixing" means mechanical alloying, mechanical mixing, and pelletizing.) Abrasion tests were carried out employing the dry abrasion tester shown in FIG. 2. For friction coefficient values, measurements were made at time intervals of one minute beginning from the start of testing, and stable measurements are shown in the table.
In Table 5, Nos. 1 through 8 represent sintered components of the invention, while Nos. 9 through 11 represent comparative materials. It is noted that only vacancy measurements are expressed in vol % and all other measurements are expressed in wt %. Symbols A and B for graphite powders signify respectively: A for natural scaly graphite powder, and B for expanded graphite powder.
TABLE 4__________________________________________________________________________ Graphite Hard Particle powder VacancyNo. Process Sn FeMo FeCr FeW FeTi FeB Total A B Total vol % Cu Remark__________________________________________________________________________1 a 10 20 0 0 0 0 20 2 0 2 18 Balance2 a 10 20 0 0 0 0 20 0 2 2 18 Balance3 a 10 20 0 0 0 0 20 10 0 10 20 Balance4 a 10 20 0 0 0 0 20 0 8 8 20 Balance5 a 10 20 0 0 0 0 20 14 0 14 20 Balance6 b 10 20 0 0 0 0 20 0 12 12 15 Balance7 c 10 20 0 0 0 0 20 5 3 8 25 Balance8 b 10 20 0 0 0 0 20 8 5 13 25 Balance9 c 10 20 0 0 0 0 20 17 0 17 20 Balance10 d 10 20 0 0 0 0 20 0 20 20 20 Balance11 d 10 20 0 0 0 0 20 10 8 18 20 Balance__________________________________________________________________________
TABLE 5__________________________________________________________________________Mechanical Property Friction Contact Characteristic Breaking Wear.sup.2) mgSample UTS Elongation strength SinteredNo. MPa % MPa μ value Δ μ.sup.1) material SS41 Damage Condition__________________________________________________________________________1 288 6.7 390 0.52 0.03 4 3 No damage2 275 5.8 366 0.50 0.02 4 2 No damage3 198 4.2 321 0.48 0.02 4 3 No damage4 196 4.0 325 0.48 0.02 4 3 No damage5 186 4.1 308 0.47 0.02 6 3 No damage6 190 3.8 310 0.47 0.02 5 2 No damage7 199 3.5 318 0.49 0.02 4 3 No damage8 189 3.6 311 0.46 0.02 4 2 No damage9 154 1.8 265 0.44 0.02 5 × 10.sup.3 3 Partially broken off10 130 1.2 223 0.41 0.02 2 × 10.sup.4 2 Partially broken off11 144 1.6 241 0.42 0.02 6 × 10.sup.3 2 Partially broken off__________________________________________________________________________ .sup.1) Δ μ indicates the difference between static coefficient of friction and dynamic coefficient of friction. .sup.2) Minus (-) sign indicates increase by deposition
Mechanical characteristics and results of friction tests of Nos. 1 through 8, which represent sintered contact components of the invention, are found satisfactory as can be seen from Table 5. Also, it has been found that scaly graphite powder and expanded graphite powder can be used in combination. Whilst, with comparative material Nos. 9 to 11, wherein the proportion of graphite powder used exceeds 15 wt %, the mechanical characteristics of the sintered material is found unfavorably low. Therefore, partial breaking-off occurred with the comparative samples during friction test.
Friction contact characteristics of sintered contact components of the invention were evaluated using the dry friction tester shown in FIG. 2, with respect to both the case in which spheroidal graphite powder is used and the case in which scaly graphite powder or expanded graphite powder is used. No. 11 sample in Table 1 which represents a sintered component incorporating spheroidal graphite powder is designated A, and Nos. 1 and 2 samples in Table 4 which represent sintered components using scaly graphite powder or expanded graphite powder are designated B and C. Changes in dynamnic coefficient of friction as measured in 5-second intervals beginning right after the start of testing are shown as test results in Table 6 and FIG. 4.
TABLE 6__________________________________________________________________________Time (sec) lapsed after the start of testingNo. 5 10 15 20 25 30 35 40 45 50 55 60__________________________________________________________________________A 0.20 0.29 0.35 0.44 0.51 0.56 0.62 0.63 0.59 0.55 0.53 0.51B 0.27 0.35 0.43 0.49 0.52 0.51 0.50 0.52 0.51 0.53 0.52 0.52C 0.25 0.33 0.41 0.45 0.49 0.52 0.52 0.50 0.49 0.50 0.50 0.50__________________________________________________________________________
As may be understood from the table, in contrast to the case where conventional spheroidal graphite powder is used, the sintered component in which scaly graphite powder or expanded graphite powder is used is not subject to any such temporary rise in friction coefficient (initial break-in phenomenon) as is seen in the first mentioned case during an initial stage after the start of testing. This ensures good stability in friction coefficient beginning from an initial stage of contact movement.
The bronze-based sintered contact component of the present invention has self-lubricating characteristics, and this enables a comparatively high friction coefficient of about 0.4 to 0.6 to be stably maintained under dry friction contact conditions, and more than 0.1 under wet friction contact conditions. The contact component is not likely to attack the counterpart material, nor is it liable to come into fusion with the counterpart. Further, the sintered component has good mechanical characteristics, such as strength, toughness, and hardness; accordingly, it can be used singly as structural material. Therefore, the sintered component of the invention can be used in various applications, including clutch material for compressors, and braking friction material for automobiles, autocycles, and other vehicles. It is also applicable to wet contact members, such as automotive transmission clutches. | The invention concerns copper-based sintered components for use as contact components such as clutches and brakes and is intended to provide a sintered component comprising hard particles admixed with and finely and uniformly dispersed in a primary particle of a matrix to provide improved friction coefficient, and in which the dispersed hard particles are inhibited from coming off the Cu--Sn alloy matrix during contact movement so that the sintered component is possessed of good friction contact characteristics and improved mechanical properties under dry and wet conditions. The sintered contact component comprises a copper-based sintered alloy having a structure such that 15 to 25 wt % of a hard particulate material having a maximum particle diameter of not more than 15 μm and a mean particle diameter of not more than 5 μm is uniformly dispersed within copper particles in an alloy matrix. | 5 |
BACKGROUND OF INVENTION
1. Field of Invention
The present invention relates to a post driver. More specifically, the present invention relates to a vibration dampening post driver for driving posts into the ground more comfortably and with less risk of injury.
2. Background Art
Fences have been used to mark territorial boundaries, prevent trespassers from entering a property, and contain livestock. These fences require that hundreds or thousands of posts be driven into the ground at regular or evenly spaced intervals. Historically, fence builders used large hammers to drive posts, though this was backbreaking—and often dangerous—work.
There have been some advances in the post driving art area. Cylindrical post driving devices, such as that shown in Hunt, U.S. Pat. No. 2,098,146—including a post tube, which is open only at the bottom of the tube, and handles on both sides of the tube—were invented long ago. In use, these post driving devices were positioned with the open end of the tube over the post, grasped at the handles, and repeatedly driven down so that the closed top end of the tube impacted the top of the post, driving the post into the ground.
However, these traditional post driving devices caused a great deal of vibration and tended to be very jarring to the hands and wrist of the user. Users of these post driving devices often experienced pain in their arms and back and typically experienced discomfort in their hands after repeated use.
More recent advances in the area included the use of springs located inside and at the top of the post tube, also known as a driver housing, to somewhat dampen the force of the blow received when the posts are driven into the ground, such as that shown in Iddings, U.S. Pat. No. 2,998,087, and Bowers, U.S. Pat. No. 5,097,912. However, these newer post driving devices with springs internal to the post tube are limited in that the size and number of springs utilized is limited, and thus the dampening ability is minimal. While better than traditional post driving devices that have little or no impact dampening abilities, even these newer post driving devices do not contain sufficient impact dampening capabilities for many people who need to drive a large number of posts. Also, the location of the dampening spring is not effective for dampening the forces transferred from the handles to the hands or wrist of the user.
Consequently, a need has long been felt for a post driving device with better dampening abilities to better cushion the jarring impact of driving posts into the ground.
BRIEF SUMMARY OF THE INVENTION
One or more of the embodiments of the present invention provide for an impact dampening post driving device which includes a shaft having an interior cavity extending to a downward facing opining or openings at a distal end of said shaft. Brackets are physically mounted onto the outside of the shaft for attaching the handles to the shaft. The handles are attached to the bracket by a floating mount. The floating mount allows for a dampening device or spring to be positioned between the handle attach points, or mounting flanges, and the brackets. For example, in one embodiment the mounting flange of a handle has an oversized aperture, and the bracket has a similarly sized aperture where the mounting flange is floatingly mounted to the bracket by threading an undersized bolt through the apertures and capturing the bolt with a nut larger than said apertures. A dampening device is then positioned within the floating region between the bracket and mounting flange. In this way, a dampening spring sits between each handle and the shaft, as opposed to the handles being mounted directly to the shaft.
The dampening device or dampening spring by definition can be any elastic device or shock absorbing device, such as for example, but not limited to a bushing made of elastomeric material or a coiled spring or any other elastic device that substantially regains its original shape after compression or extension.
A user can grasp the handles and lift the device over a post such that the post is aligned with the opening at the bottom of the shaft. The user can then force the shaft down over the post such that the post enters the interior cavity through the downward facing opening and strike the closed top end of the shaft. This creates vibration and shock in the shaft, but the dampening springs between the shaft and the handles greatly reduce the vibration and shock reaching the handles held by the user, thus reducing the force transferred to the hands, arms and wrist of the user.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference may be made to the accompanying drawings in which:
FIG. 1 is an elevation view of the post driving device.
FIG. 2 is a bottom view of the post driving device shown in FIG. 1 .
FIG. 3 is a magnified view of the top dampening assembly shown in FIG. 1 .
FIG. 4 is a magnified view of the bottom dampening assembly shown in FIG. 1 .
FIG. 5 is an elevation view of an alternative embodiment.
FIG. 6 is a bottom view thereof.
DETAILED DESCRIPTION OF THE INVENTION
A shock-dampening post driving device, according to an embodiment of the present invention, includes a shaft having an axially extending interior cavity that extends to a closed top end of the shaft and to a distal open bottom end of the shaft. The closed top end of the shaft forms a striking surface that is used to strike posts. The shaft also has a first mounting bracket extending from an exterior wall of the shaft. Additionally, an upper mounting flange of a handle is mounted to the first mounting bracket of the shaft by a first floating mount with a first floating region. Further, a first dampening spring is positioned between the upper mounting joint of the handle and the first mounting bracket. This first dampening spring extends into the first floating region, where it dampens vibration between the shaft and the handle.
Another embodiment of a shock-dampening post driving device includes a handle mounted to a shaft by a first floating mount having a first floating region, where the first floating mount allows the handle to float or oscillate within said first floating region. Additionally, a first dampening spring is positioned between the handle and the shaft, where the first dampening spring extends into the first floating region, and where the first dampening spring dampens vibration between the shaft and the handle.
An embodiment of a shock-dampening post driving method includes striking an object with [a closed top end of] a shaft [while said object is in an axially extending interior cavity of said shaft] and dampening vibration between the shaft and a handle. The handle is floatingly attached to the shaft by a floating mount, and the dampening occurs in a dampening spring positioned in a floating region of the floating mount between said handle and said shaft.
FIGS. 1 and 2 illustrate multiple views of a post driving device 100 according to a preferred embodiment of the present invention. As shown in FIG. 1 , the post driving device 100 includes a cylindrical shaft 110 having a closed top end 112 forming a striking surface 117 , and an axially extending interior cavity 114 extending to a distal open bottom end 116 . The post driving device 100 of FIG. 1 further includes two handles 120 , two upper dampening assemblies 130 , two lower dampening assemblies 140 , and a level 150 .
Each handle 120 is physically connected to an upper dampening assembly 130 and a lower dampening assembly 140 . Both upper dampening assemblies 130 are physically mounted to the cylindrical shaft 110 toward the top end 112 of the cylindrical shaft 110 . Both lower dampening assemblies 140 are physically mounted to the cylindrical shaft 110 toward the bottom end 116 of the cylindrical shaft 110 . The level 150 is physically mounted proximate the top end 112 of the cylindrical shaft 110 . The axially extending interior cavity 114 is inside the cylindrical shaft 110 and extends to the open bottom end 116 .
In operation, a post is held vertically on the spot where it is to be driven into the ground. The open bottom end 116 of the cylindrical shaft 110 is then placed over the top end of the post, and the post is allowed to slide up through the open bottom end 116 of the cylindrical shaft 110 into the axially extending interior cavity 114 of the cylindrical shaft 110 until the top of the post comes to rest against the closed top end 112 of the cylindrical shaft 110 . The level 150 in the cylindrical shaft 110 then alerts the user if the post is currently perpendicular to the ground
The user of the post driver device 100 grasps the handles 120 , one in each hand, and lifts the post driver device 100 . Once the post driver device 100 has been sufficiently lifted, the user quickly forces the post driver device 100 downward onto the post, such that the post again slides up through the open bottom end 116 of the cylindrical shaft 110 into the axially extending interior cavity 114 of the cylindrical shaft 110 until the closed top end 112 of the cylindrical shaft 110 , which acts as a striking surface, forcefully impacts the top of the post, driving the post into the ground. This impact creates a great deal of vibration and shock in the cylindrical shaft 110 that is transferred to the handles 120 . The upper damper assemblies 130 and the lower damper assemblies 140 dampen the vibration generated in the cylindrical shaft 110 before the shock and vibration reach the hands and body of the user. The previous post driver designs, which have the handles rigidly mounted to the cylindrical shaft, does not dampen the force transferred to the hands of the user, and the post drivers having the interior springs are not very effective because they only require the user to drive downward with a greater velocity and more force in order to drive a post.
The cylindrical shaft 110 may alternatively have a non-circular cross-section, such as a triangular, rectangular, or pentagonal cross-section, or any other shaped cross-section. The cylindrical shaft 110 may be made of a metal or metal alloy, or other material conducive to repeated impacts. The level 150 may alternatively be mounted anywhere on the post driving device 100 , and more levels may be added to give information on more than just one axis. The closed top end 112 of the cylindrical shaft 110 may have some sort of a weight or durable substance with which to exert even more force on a post being driven into the ground. The post driver device 100 may be used to drive things other than posts in directions other than down into surfaces other than the ground. There may alternatively be more or less than two handles 120 , and more or less than two upper damper assemblies 130 and two lower damper assemblies 140 . Further, handles 120 may alternatively be mounted to more or less than two dampener assemblies 130 , 140 , though never less than one.
FIG. 3 shows a magnified view of the upper damper assembly 130 according to an embodiment of the present invention. As shown in FIG. 3 , the upper damper assembly 130 includes a first mounting bracket 131 , a first damper 132 , a first bolt 133 , a first nut 134 , a third mounting bracket 135 , and a handle 120 having an upper mounting flange 125 at one end.
The first mounting bracket 131 and the third mounting bracket 135 are affixed to the cylindrical shaft 110 . Between the two mounting brackets 131 , 135 are, from bottom to top, the first damper 132 , the upper mounting flange 125 of a handle 120 , and the first nut 134 . The first bolt 133 is inserted through an aperture of the first mounting bracket 131 up through an aperture in the first damper 132 and an aperture in the upper mounting flange 125 of a handle 120 , and is secured in place by the first nut 134 . A portion of the first bolt 133 extends through the first nut 134 and up through an aperture in the third mounting bracket 135 . This creates a floating mount between the upper mounting flange 125 of the handle and the brackets 131 , 135 attached to the cylindrical shaft 110 .
In operation, the first bolt 133 and first nut 134 hold the components of the upper damper assembly 130 in place. The third mounting bracket 135 and first mounting bracket 131 connect the upper damper assembly 130 to the cylindrical shaft 110 . The first bolt 133 connects the first damper 132 and the upper mounting flange 125 (and thus the handle 120 ) to the third mounting bracket 135 and the first mounting bracket 131 , while the first nut 134 secures the first bolt 133 in place. The positioning of the components allows the upper mounting flange 125 (and thus the handle 120 ) to oscillate or float along the first bolt 133 and compress the first damper 132 when the closed top end 112 of the cylindrical shaft 110 is brought down and strikes an object. This dissipates much of the vibration and shock before it can travel from the cylindrical housing 110 to the handles 120 . The first damper 132 then rebounds, pushing the upper mounting flange 125 (and thus the handle 120 ) back to its original position, completing one oscillation. In other words, the floating mount created by this assembly allows the upper mounting flange 125 of the handle 120 to oscillate or float up and down along a floating region 137 in which the damper 132 is installed.
In the alternative, things other than the first bolt 133 and first nut 134 may be used to hold the components of the upper assembly 130 in place in a floating relationship, such as adhesive, rivets, welding or other bonding techniques. The first damper 132 may take the form of dense foam or other elastomeric material or shock absorbing material, or may alternatively be a dampening spring or other mechanical shock absorbing device such as a pneumatic or hydraulic shock absorber. The order of the components in the upper damper assembly 130 may change, such as the position of the first nut 134 moving from under to over the third mounting bracket 135 or any similar change. The first damper 132 size and dampening ability may vary according to the needs of the user.
FIG. 4 shows a magnified view of the lower damper assembly 140 according to an embodiment of the present invention. As shown in FIG. 4 , the lower damper assembly 140 includes a second mounting bracket 141 , a second damper 142 , a second bolt 143 , a second nut 144 , and a handle 120 having a lower mounting flange 127 at one end.
The second mounting bracket 141 is connected to the cylindrical shaft 110 . Above the second mounting bracket 141 is, from bottom to top, the second damper 142 , and the lower mounting flange 127 of the handle 120 . The second bolt 143 is inserted down through an aperture in the lower mounting flange 127 , through an aperture in the second damper 142 and an aperture in the second mounting bracket 141 , and is secured in place by the second nut 144 below the second mounting bracket 141 to a portion of the second bolt 143 extending through an aperture in the second mounting bracket 141 . This creates a floating mount between the lower mounting flange 127 of the handle 120 and the second mounting bracket 141 attached to the cylindrical shaft 110 .
In operation, the second bolt 143 and second nut 144 hold the components of the lower damper assembly 140 in place. The second mounting bracket 141 connects the lower damper assembly 140 to the cylindrical shaft 110 . The second bolt 143 connects the second damper 142 and the lower mounting flange 127 of the handle 120 to the second bracket 141 , while the second nut 144 secures the second bolt 143 in place. The positioning of the components allows the lower mounting flange 127 (and thus the handle 120 ) to oscillate or float along the second bolt 143 and compress the second damper 142 when the closed top end 112 of the cylindrical shaft 110 is brought down and strikes an object. This dampens much of the vibration and shock before it can travel from the cylindrical housing 110 to the handles 120 . The second damper 142 then rebounds, pushing the lower mounting flange 127 (and thus the handle 120 ) back to its original position, completing one oscillation. In other words, the floating mount created by this assembly allows the lower mounting flange 127 of the handle 120 to oscillate or float up and down along a floating region 147 in which the damper 132 is installed.
In the alternative, things other than the second bolt 143 and second nut 144 may be used to hold the components of the lower assembly 140 in place, such as adhesive, rivets, welding or other bonding techniques. The second damper 142 may take the form of dense foam or elastomeric material or shock absorbing material, or may alternatively be a dampening spring or other mechanical shock absorbing device such as a hydraulic or pneumatic shock absorber. The order of the components in the lower damper 140 assembly may change, such as the orientation of the second bolt 144 being flipped 180 degrees such that it is inserted from the top down as opposed to from the bottom up, or any similar change.
FIGS. 5 and 6 illustrate multiple views of a post driving device 500 according to a preferred embodiment of the present invention. As shown in FIG. 5 , the post driving device 500 includes a cylindrical shaft 510 having a closed top end 512 forming a striking surface 517 , and an axially extending interior cavity 514 extending to a distal open bottom end 516 . The post driving device 500 of FIG. 5 further includes two handles 520 , two upper dampening assemblies 530 , two lower dampening assemblies 540 , and a level 550 .
Each handle 520 is physically connected to an upper dampening assembly 530 and a lower dampening assembly 540 . Both upper dampening assemblies 530 are physically mounted to the cylindrical shaft 510 toward the top end 512 of the cylindrical shaft 510 . Both lower dampening assemblies 540 are physically mounted to the cylindrical shaft 510 toward the bottom end 516 of the cylindrical shaft 510 . The level 550 is physically mounted proximate the top end 512 of the cylindrical shaft 510 . The axially extending interior cavity 514 is inside the cylindrical shaft 510 and extends to the open bottom end 516 .
In operation, a post is held vertically on the spot where it is to be driven into the ground. The open bottom end 516 of the cylindrical shaft 510 is then placed over the top end of the post, and the post is allowed to slide up through the open bottom end 516 of the cylindrical shaft 510 into the axially extending interior cavity 514 of the cylindrical shaft 510 until the top of the post comes to rest against the closed top end 512 of the cylindrical shaft 510 . The level 550 in the cylindrical shaft 510 then alerts the user if the post is currently perpendicular to the ground
The user of the post driver device 500 grasps the handles 520 , one in each hand, and lifts the post driver device 500 . Once the post driver device 500 has been sufficiently lifted, the user quickly forces the post driver device 500 downward onto the post, such that the post again slides up through the open bottom end 516 of the cylindrical shaft 510 into the axially extending interior cavity 514 of the cylindrical shaft 510 until the closed top end 512 of the cylindrical shaft 510 , which acts as a striking surface, forcefully impacts the top of the post, driving the post into the ground. This impact creates a great deal of vibration and shock in the cylindrical shaft 510 that is transferred to the handles 520 . The upper damper assemblies 530 and the lower damper assemblies 540 dampen the vibration generated in the cylindrical shaft 510 before the shock and vibration reach the hands and body of the user. The previous post driver designs, which have the handles rigidly mounted to the cylindrical shaft, does not dampen the force transferred to the hands of the user, and the post drivers having the interior springs are not very effective because they only require the user to drive downward with a greater velocity and more force in order to drive a post.
The cylindrical shaft 510 may alternatively have a non-circular cross-section, such as a triangular, rectangular, or pentagonal cross-section, or any other shaped cross-section. The cylindrical shaft 510 may be made of a metal or metal alloy, or other material conducive to repeated impacts. The level 550 may alternatively be mounted anywhere on the post driving device 500 , and more levels may be added to give information on more than just one axis. The closed top end 512 of the cylindrical shaft 510 may have some sort of a weight or durable substance with which to exert even more force on a post being driven into the ground. The post driver device 500 may be used to drive things other than posts in directions other than down into surfaces other than the ground. There may alternatively be more or less than two handles 520 , and more or less than two upper damper assemblies 530 and two lower damper assemblies 540 . Further, handles 520 may alternatively be mounted to more or less than two dampener assemblies 530 , 540 , though never less than one. The handle can include a dampening device system 550 and 551 and gripper handle 552 in addition to the damper assembly 130 described above or in lieu of damper assembly 130 .
One or more embodiments of the present invention dissipate the vibration and shock that are created by driving posts into the ground more readily than current post drivers through the use of more and bigger and better dampers mounted directly between the handles and cylindrical shaft of the device. This increased shock absorption decreases the strain on the user of the device, which lessens the likelihood of injury and allows users to use the device for longer periods of time.\
While particular elements, embodiments, and applications of the present invention have been shown and described, it is understood that the invention is not limited thereto because modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. It is therefore contemplated by the appended claims to cover such modifications and incorporate those features which come within the spirit and scope of the invention. | A post driver having a dampening device adapted to isolate the hands and arms of the user from shock. | 4 |
CLAIM OF PRIORITY
[0001] This application claims the benefit of the filing date of U.S. Provisional Application No. 60/867,689, filed Nov. 29, 2006, the contents of which are hereby entirely incorporated by reference for all purposes.
FIELD OF THE INVENTION
[0002] The present invention is predicated upon an improved system and method for providing a parking brake assembly and more specifically a parking brake actuator.
BACKGROUND OF THE INVENTION
[0003] In the field of automotive manufacturing, parking brake assemblies are commonly used to prevent movement of a vehicle. In a typical parking brake assembly, an operator engagement feature, such as a pedal, lever or otherwise, is providing for causing engagement and disengagement of a parking brake actuator mechanism. Typically the operator engagement feature is remotely located and attached to the parking brake actuator, such as through a linkage (e.g. cable, wire, or otherwise), for causing movement to one or more components of the actuator. Through this movement and the configuration of the parking brake actuator, the shoes or pads of the vehicle braking system move to frictionally engage a corresponding component, such as a brake drum, rotor or otherwise.
[0004] In one particular application, a parking brake assembly may include a drum-in-hat brake system. In this application, the assembly commonly includes a parking brake actuator mechanism linkably attached to an engagement feature and configured to radially move the brake shoes outwardly against an interior surface of a brake drum, in response to operator input. Upon release of the actuator, the engagement feature returns to an original position thereby allowing the brake shoes to return to an original position through one or more springs associated with the drum brake system.
[0005] Examples of parking brake assemblies can be found in U.S. Pat. Nos. 1,913,156, 2,118,188, 4,678,067, 4,844,212, 4,887,698, 5,180,037, 5,400,882, 5,529,149, 5,957,247, 6,412,609, 6,464,046 and 6,666,302, all incorporated by reference for all purposes. The present invention improves on these parking brake assemblies as shown and described herein.
SUMMARY OF THE INVENTION
[0006] The present invention provides improved parking brake and actuator assemblies having improved duty cycle and lower production cost as compared to prior assemblies.
[0007] In one aspect, the present invention provides an actuating mechanism for a parking brake. The actuator mechanism includes a lever having a first pivot site and a second pivot site. The actuating mechanism also includes a first strut configured to pivotally engage the actuating lever at the first pivot site and a second strut configured to engage the actuating lever at the second pivot site. Upon displacement of the actuating lever, the first strut, the second strut, or both, are moveable generally longitudinally, relative to each other, for engaging one or more braking elements. This causes contact surfaces of the braking elements (e.g. a brake pad or shoe) to move into or out of braking engagement with a corresponding opposing braking component (e.g. a rotor or brake drum). In this aspect, the positioning of the actuating mechanism is achieved through engagement with the one or more braking elements. Also, optionally the first strut, second strut and/or lever may be reversible for allowing for installation on a vehicle brake assembly located on either side of the vehicle, or for permitting easy correction of improperly installed components.
[0008] In another aspect, the present invention provides a parking brake assembly. The assembly includes a housing and one or more braking elements having contact surfaces pivotally mounted with respect to the housing. The one or more braking elements are adapted to rotate outwardly from an axis to provide contact with a corresponding braking component. The assembly further includes an actuating mechanism that includes: a) a lever having a first pivot site and a second pivot site; b) a first strut pivotally engaging the actuating lever at the first pivot site and having a first longitudinal axis; and c) a second strut engaging the actuating lever at the second pivot site and having (i) a second longitudinal axis that is generally in parallel alignment with the first longitudinal axis and (ii) a contact surface engaging a first notch formed in at least one of the braking elements. Upon displacement of the actuating lever, the first strut, the second strut or both are moved generally longitudinal relative to each other for bringing the contact surface of at least one of the braking elements into or out of braking engagement with the corresponding braking component.
[0009] Still further, in some of the additional aspects, the present invention also provides the ability to mount the actuator mechanism outboard from the anchor block, which is used to assist in positioning of the braking elements. Also, the configuration of the braking elements and actuator mechanism allows the actuator mechanism to be mounted directly to the braking mechanism, without the use of additional mounting features. Further, the actuator mechanism may be configured free of mechanical retention means (such as rivets, mounting features associated with an anchor block, or otherwise) for maintaining position of the actuator components with respect to each other. Still further, during actuation of the actuator mechanism, the contact area between the actuator and braking elements are substantially free of frictional forces.
[0010] It should be appreciated that the above referenced aspects and examples are non-limiting as other exists with the present invention, as shown and described herein. For example, any of the above mentioned aspects or features of the invention may be combined to form other unique configurations, as described herein, demonstrated in the drawings, or otherwise.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates an exploded perspective view of a brake assembly including one embodiment of a parking brake mechanism of the present invention.
[0012] FIG. 2 illustrates a front view of the brake assembly and parking brake mechanism shown in FIG. 1 .
[0013] FIG. 3 illustrates a perspective view of a parking brake mechanism according to the teachings of the present invention.
[0014] FIG. 4 illustrates an exploded perspective view of the parking brake mechanism shown in FIG. 3 .
[0015] FIGS. 5A and 5B illustrate a cross-section view of the parking brake mechanisms, shown in FIG. 2 , in different positions.
[0016] FIG. 6 illustrates a cross-section view of the parking brake mechanism shown in FIG. 3 .
[0017] FIG. 7 illustrates a side view of a first actuating lever of a parking brake mechanism of the present invention.
[0018] FIG. 8 illustrates a side view of a second actuating lever of a parking brake mechanism of the present invention.
[0019] FIGS. 9 through 11 illustrate different engagement configurations between parking brake mechanisms and braking elements of the present invention.
DETAILED DESCRIPTION
[0020] In general, the present invention is predicated upon an improved vehicle brake system. More particularly, the present invention is predicated upon an improved parking brake actuator for improving a parking brake assembly of a vehicle braking system.
[0021] The parking brake assembly provides advantages over the prior art by improving longevity of the parking brake system. For example, in one aspect, this advantage is achieved through the unique configuration of the components comprising the parking brake actuator. In one possible construction, this may also be achieved through a substantial avoidance of surface friction, wear, or both, often encountered by the components during actuation of the parking brake system. That is, the present invention makes possible the elimination of camming of a lever against a brake shoe.
[0022] In contrast to many of the previous system, the contact surfaces between the parking brake actuator mechanism and the corresponding braking element (e.g. brake shoe, pad, etc.) are substantially free of frictional resistance when an edge associated with an actuator lever engages a brake shoe. The above improvement is achieved through the modification of the parking brake actuator to remove the cammed surface used to cause movement of the braking element in order to engage a corresponding braking component (e.g. brake drum, rotor, or otherwise). Thus in one particular embodiment, a rotating lever, having offset pivotal connections, is used in the actuator to cause movement of connecting members to the braking element.
[0023] The parking brake assembly also provides the ability to reduce manufacturing cost of the brake assembly by improving the brake assembly. The assembly also provides for improved installation, inspection and replacement of assembly components. For example, in one aspect, the components forming the parking brake actuator mechanism are mounted to, and kept in place by, the component forming the brake assembly and more specifically the braking element upon which the actuator acts (e.g. brake shoe, pad etc.). The actuator assembly can be carried in the brake assembly by an inwardly located anchor member. In addition thereto, or as an alternative, the actuator assembly can be held in place by an opposing brake shoes or pads.
[0024] In another aspect, the actuator mechanism employs a substantially flat and/or symmetrical lever that is readily removable and reversible to be interchangeable between brake assemblies existing on either side of an axle. However, the lever may be bent or shaped (e.g. L-shaped or otherwise) to form a non-flat member that my still be interchangeable. This interchangeability is the result of the reversibility of the components wherein one or more of the components making up the parking brake actuator mechanism, and preferably all of the components, are reversible to adapt to application or installation on opposite sides of a vehicle. This is in contrast to many of the prior art brake components which require specific components for the braking systems on each side of the axle. However, it is contemplated that the actuator mechanism, and/or components thereof, may not be reversible but instead specifically designed for a specific brake assembly, wheel or axel, or side thereof.
[0025] In yet another aspect, as desired, the parking brake actuator mechanism may be formed substantially free of mechanical fasteners (e.g. rivets, bolts, or otherwise) for fastening the components of the actuator together (e.g. permanently fastened) or for attachment of the actuator mechanism to the braking system. As should be appreciated, the elimination of fastening components reduces cost by eliminating not only the fastening component, but also eliminating the time necessary to utilize such components.
[0026] Of course, other aspects of the present invention, as shown and described herein, also contribute to the above mentioned advantageous and other advantageous as implicitly or explicitly described herein.
[0027] In general, referring to FIGS. 1 and 2 , the present invention provides a parking brake actuator mechanism 10 for use with a brake assembly 12 . The parking brake assembly is adapted for use and more preferably to be incorporated into one or more braking systems of a vehicle. Typically, this includes a single brake assembly associated with a wheel of an axle, but of course may extend to more than one including all of the vehicle wheels.
[0028] The brake assembly 12 may include any brake system used with a vehicle. Preferably, at least one of the brake assemblies includes a parking brake assembly therewith. The brake assembly may include caliper brakes, drum brakes or otherwise. Such braking systems include one or more brake pads or shoes configured for engagement with a rotating member of the vehicle wheel, such as brake rotor or drum. The actuation of the brake system components generally comprise the hydraulic use of brake fluid to fluidly apply a load against a brake component, such as a piston, which is further connected to one or more components configured to cause or otherwise move the braking elements used to engage the moving components of the wheel. In contrast, the actuation of the parking brake assembly or mechanism typically utilizes mechanical means such as levers, cables or the like.
[0029] In one particular advantageous application, the parking brake assembly is utilized with a drum brake assembly, and particularly a drum in hat assembly. The drum brake assembly includes a housing 16 for the mounting of various components of the brake assembly and optionally attachment to the wheel or axle of the vehicle. In one configuration, the housing comprises a mounting plate formed through a stamping or casting procedure, such as commonly done in shaping metal components.
[0030] The housing 16 includes one or more mounting structures for the mounting of one or more braking elements (e.g. a shoe) 18 which may further include a friction pad 20 for engagement with a corresponding braking structure, such as a brake drum or rotor, and a support member 22 therefor.
[0031] In one preferred configuration, the support members 22 of the braking elements 18 are configured for engagement with the parking brake actuator mechanism 10 at a first end and an adjustment mechanism 13 at a second end. Still further, in one highly preferred configuration, as discussed further herein, the support members of the braking element may include one or more notch support members or portions 24 for engagement with the parking brake actuator at one or more locations. For example, the support member of the braking element may be notched so that it can effectively engage and co-act with the actuator mechanism.
[0032] In one approach, the actuator mechanism is carried in the assembly by a suitable carrier that positions the mechanism so that it remains generally in a fixed location relative to the lever of the actuator mechanism but still allows the individual components to translate relative to each other for engagement with a brake element, such as a shoe or pad. One approach is to employ an anchor block 26 for maintaining the position and/or for guiding the braking elements during engagement with the corresponding braking structure. By example, one suitable anchor block can be found in U.S. patent application Ser. No. 11/522,552, filed on Sep. 14, 2006, herein entirely incorporated by reference for all purposes. In one preferred configuration, the anchor block is located inboard (i.e. toward the center of the assembly) with respect to the parking brake actuator. It is also possible that it can be located on the outboard side of the braking element.
[0033] The brake assembly may further include one or more biasing members 28 (e.g., spring or otherwise) for providing return force for the braking elements. The one or more biasing members provide returning force of the braking elements during both the application of the brakes during typical operating use and during application of the parking brake system of the present invention. As shown, the brake assembly may also include spring biased mounting features 27 for providing pivotal attachment of the braking elements 18 to the housing 16 .
[0034] It should be appreciated that other components associated with a typical brake drum assembly may be utilized and/or otherwise incorporated with the braking system of the present invention. Such additional features may be found in copending commonly owned U.S. patent application Ser. No. 11/522,552, filed on Sep. 14, 2006. Such features may also be found in commonly owned U.S. Pat. Nos. 7,070,025, 7,044,275, 6,454,062, 6,328,391, 6,321,889, 6,290,036, 6,286,643, 6,186,294, 6,131,711, 6,119,833, 6,059,077, 5,964,324, 5,404,971, 5,305,861, 5,125,484, 5,038,898, 4,919,237, 4,782,923, 4,303,148, 4,270,634, or otherwise, all entirely incorporated herein for all purposes.
[0035] The parking brake assembly includes a parking brake actuator mechanism 10 for causing engagement of one or more braking elements 18 with a corresponding braking component. The parking brake assembly includes linkages 29 for connecting the actuator to an operator engagement feature, such as a pedal, lever, or otherwise, for causing engagement and disengagement of the parking brake actuator mechanism 10 . Typically the operator engagement feature is remotely located, within a cabin of a vehicle, and linkably attached to the parking brake actuator, via a linkage, cable, wire, or otherwise.
[0036] The parking brake actuator mechanism 10 is mounted to a portion of the brake assembly, preferably with one or more brake shoes or other braking element, and more preferably between two opposing braking elements 18 . In one configuration, the actuator mechanism is located outboard of an anchor block 26 of the brake assembly to improved accessibility and reduce manufacturing cost. The actuator mechanism includes two generally opposing (and optionally contacting) strut members, one or both being configured to engage the braking elements for driving the braking elements into braking engagement with a brake drum or other braking surface. Upon receiving force from an operating engagement feature, the struts of the actuator mechanism are configured to move with respect to one another to transfer motion originating from the engagement feature to the brake shoe or other braking elements 18 of the brake assembly 12 . The engagement between the struts and brake shoe or other element generally will from a direct contact force and thus may be substantially free of sliding and frictional movement between the contact surfaces of the actuator mechanism and the braking elements of the braking system. This is because the force applied to the braking element comprises an axial force as opposed to a rotational cam (e.g. sweeping) force.
[0037] Referring to FIGS. 3 through 6 , one configuration of a parking brake actuator mechanism 10 is shown. In general, the parking brake actuator includes an actuating lever 30 configured to be linkably attached to the operator engagement feature of the parking brake assembly, via linkage 29 . Upon application of a force, such as by the tensioning of the linkage, the lever is caused to rotate along a plane for causing one or more, and preferably a first strut 32 and a second strut 34 , to move relative to each other. For example, as the lever is rotated each strut moves longitudinally, in generally different (e.g. opposite) directions, relative to each other and also generally in the same or parallel planar direction as the motion of the lever.
[0038] The actuating lever 30 extends along a longitudinal axis and includes a first end portion for engagement with the first and second strut 32 , 34 and a second end portion for engagement with linkage 29 . The lever engages the first and second strut 32 , 34 through a pivotal engagement. In the configuration shown, the actuating lever includes openings through which pins or other elongated projecting members from the first and second strut pass. For example, the actuating lever includes a generally round aperture 36 and a generally elongated slot 38 for receiving projecting members, such as a pin or otherwise, that are associated, connected or formed with the first and second strut. Alternatively, it is contemplated that holes or slots associated with the lever may be included on the struts wherein the lever includes one or more projections for engagement therewith. Still further, as shown in FIGS. 7 and 8 , it is contemplated that the location of aperture 36 and slot 38 may be switched.
[0039] The lever also includes a connector 40 for attachment to an engagement feature or a connecting linkage 29 therefore. In one embodiment, the shape of the lever may be configured as a hook to provide improved transfer of leverage force from the operator engagement feature to the components of the actuator mechanism. Advantageously, this hook configuration also aids in securing engagement with linkage 29 . Other lever shapes may be employed as desired.
[0040] Referring to FIG. 4 the first strut 32 comprises a first elongated member having a first longitudinal axis. The first strut includes a central portion and opposing distal portions. The strut includes a first face, a second face, an upper portion, and lower portion, and a projection 42 extending from the first face having a free end, for defining a pivot axis. As shown, the projection may be integrally formed with the first strut; however, the projection may also comprise a separate component, such as a pin, or the like. The projection and pivot axis are located generally toward the center of the first strut and in the upper portion of the strut.
[0041] The distal portions of the first strut are located in a different plane relative to the central portion and are generally coplanar with the free end of the projection. As shown, the distal portions include contact surfaces 44 for engagement with the braking elements 18 of the brake assembly 12 , and optionally with one or more notched portions 24 formed in the braking elements. Preferably, the distal portions further include one or more, and preferably two fingers 48 , extending along the axis to form a forked configuration for assisting in the engagement and maintaining of position of the first strut with respect to the braking element. As should be appreciated, the fingers are located on opposite sides of the support member 22 and act to prevent or limit movement of the first strut with respect to the braking element.
[0042] The second strut 34 comprises a second elongated member having a second longitudinal axis. The second strut includes a central portion and opposing distal portions. As with the first strut, the second strut also includes a first face, a second face, an upper portion, a lower portion, and also includes a second projection 50 from the second face having a free end, for defining a second pivot axis. The projection may be integrally formed with the second strut; however, the projection may also comprise a separate component, such as a pin, or the like. The projection and pivot axis are located generally toward the center of the second strut and in the lower portion of the strut.
[0043] The distal portions of the second strut are located in a different plane relative to the central portions and extend away from the free end of the projection. The distal portions include contact surfaces 52 for engagement, and application of force, with the braking elements 18 of the brake assembly 12 , and optionally with one or more notched portions 24 formed in the braking elements. Preferably, the distal portions further include one or more, and preferably two fingers 54 , extending along the axis to form a forked configuration for assisting in the engagement and maintaining of position of the second strut with respect to the brake shoe or other braking element. The fingers substantially limit movement towards and away from the brake assembly housing.
[0044] Referring again to the entire actuator mechanism, as shown in FIGS. 3 , 5 A, 5 B and 6 , the first strut 32 , second strut 34 and actuator lever 30 join together to form a linking relationship. In doing so, the first strut is in opposing relation with the second strut such that at least a portion of the second face of the second strut contacts at least a portion of the distal portions of the first face of the first strut. This relationship forms a gap 56 between a portion of the first face of the first strut and the second face of the second strut adjoining the central portion of the first strut.
[0045] The actuator lever 30 is positioned for longitudinal movement in the gap 56 formed between the first strut and the second strut. Referring to FIG. 6 , the first projection 42 penetrates the round aperture 36 , and the second projection 50 penetrates the elongated slot 38 , for providing pivotal motion of the lever about either or both of the first or second projection. Upon actuation of the lever, and upon pivoting of the lever about either or both of the first or the second projection, the first strut, the second strut or both, move relative to each other for bringing the first strut, the second strut or both in contact with a braking element 18 and actuating the attached friction pad 22 to frictionally engage an opposing braking component, such as a brake drum.
[0046] During pivotal movement of the actuator lever 30 about projection 42 , projection 42 moves the first strut in a first direction and projection 50 moves the second strut in a second and opposite direction. Preferably, the first and second directions are parallel with each other. Accordingly, to allow for this parallel motion and to prevent binding slot 38 is provided for allowing movement of projection 50 and hence the second strut with respect to the first strut and actuator lever. Of course, as previously discussed and shown in FIGS. 7 and 8 , the configuration of aperture 36 and slot 38 may be reversed.
[0047] During actuation of the parking brake mechanism, e.g. rotation of the actuator lever 30 , the first and second strut move with respect to each other to apply a force suitable for movement of the braking elements 18 . To facilitate engagement between the first and second strut with the braking elements, each braking element includes a notch 24 for receiving the first and second strut. These notches assist in maintaining the position of the parking brake mechanism with respect to the braking elements and anchor block 26 during both engagement and non-engagement of the parking brake assembly.
[0048] For example, referring to FIGS. 9 through 11 , three notch configurations are shown that may be used with the parking brake mechanism of the present invention. FIG. 9 illustrates a first notch configuration wherein the braking element 18 includes a notch 24 having a first seat 58 and a second seat 60 for engagement with the first strut and second strut, respectively. The first seat prevents outward movement of the parking brake mechanism and the second seat prevents inward movement of the parking brake mechanism. FIG. 10 illustrates a second notch configuration where the braking element 18 includes a notch 24 having a single seat 62 for engagement with both the first and second strut. The singe seat 62 is configured to prevent both outward and inward movement of the parking brake mechanism 10 with respect to the braking element. FIG. 11 illustrates a third notch configuration where the braking element includes a notch 24 having a single seat 64 for engagement with first strut. In this configuration, the single seat prevents outward movement of the parking brake actuator while the anchor block 26 prevents inward movement of the parking brake actuator. It should be appreciate that other configurations are contemplated.
[0049] As should be appreciated with the above configurations, the length of the first and second strut and position of corresponding contact surface 44 52 may vary depending on the seat configuration of notch 24 . Further, it should also be appreciated, as shown in FIGS. 5A and 5B , that fingers 48 and 54 prevent movement of the parking brake mechanism 10 in a direction perpendicular to the surface of the braking element shown in FIGS. 9 through 11 .
[0050] The contact area between the actuator mechanism 10 and the braking element 18 may be dependent upon, at least in part, the applied load and friction (and anticipated wear) between the contact surfaces of the actuator mechanism (e.g. struts) and braking element. As previously mentioned, contact between the parking brake mechanism and braking elements comprise axial force against the braking elements, which is substantially parallel with the axial movement of the first and second struts. This axial force results in little to no friction force between the parking brake assembly 10 and the braking element 18 , thereby, substantially increasing the life of the parking brake assembly in contrast to sliding, sweeping and/or cammed parking brake systems.
[0051] In one embodiment, the contact areas between the struts and the braking element may be considerably smaller than previous brake assemblies. It is anticipated that, due to the reduction in potential surface friction wear, the required contact surface area between the struts and braking element is reduced by at least 5%, or at least 10%, or at least 20%, or at least 50%, or more. While the contact surface may vary, it is contemplated that the contact surface area may be less than 24 mm 2 , 10 mm 2 , more even less than about 5 mm 2 .
[0052] The components forming the actuator mechanism 10 may be formed of similar or dissimilar materials. They may be formed of a high strength material, a hardened material (selectively or entirely), or combinations thereof, to translate or receive the application of force to or from other the components of the actuator. Optionally, they may also be configured to resist wear from the rotational movement between the strut members 32 , 34 and lever 30 , from contact between the strut members and braking elements, and/or from contact between the lever and engagement feature. These contact surfaces may be selectively or entirely coated with friction reducing material, or surface treated for locally hardening or otherwise altering the physical characteristics of the material. This optional wear resistant feature may be derived from the composition of the material forming the actuator components or may comprise applying over some or all of the contacting surfaces a coating, surface treatment, a laminated layer, or any combination thereof. Suitable materials for forming the components of the actuator mechanism include metal, ceramic or other high strength materials. In one configuration the material forming the components comprise a high strength steel such as SAE J1392 050 XLF. However, other materials are available and anticipated with the present invention such as those commonly used in the industry for forming mechanical brake components for vehicles, or otherwise.
[0053] The actuator components may be formed using suitable forming techniques for the given material. However, with the use of metal, it is contemplated that the components may be formed through a stamping process, a machining process, or both. Accordingly, in at least one configuration, the activating lever 30 , struts 32 , 34 , or both, may comprise a substantially flat member. The thickness of the actuator components may comprise any suitable thickness. For example, the thickness of the actuator components may be from about 3 mm to about 8 mm. The lever, struts, or both, may be interchangeable and reversible to be configured for placement on a brake assembly located on either side of a vehicle.
[0054] It should be appreciated that one or more additional features may be added to further improve the performance capabilities of the present invention. For example, a lubricant may be used between contact surfaces of the components of the actuator mechanism. The lubricant may also be used between the actuator mechanism and other components such as components of the brake assembly, engagement feature, or otherwise. Suitable lubricants include grease or other similar types of lubricants that have surface cohesion properties for maintaining the lubricant on the components in which it is lubricating.
[0055] In general, for operation of one of the preferred assemblies herein, the parking brake assembly is activated through an application of force upon the engagement feature. The application of force is translated to one end of the actuator lever 30 via linkage 29 for applying a tensile or compressive force to move the lever, or otherwise. This application of force causes the actuator lever to rotate with respect to the first and second strut 32 , 34 as a result of the staggered pivotal connection between the first and second strut. As the actuator lever rotates, through the pivotal connections, the first and second strut moves away from each other, or outwardly, to engage braking elements 18 located on opposite sides of the actuator mechanism 10 and apply a force thereto sufficient to cause the braking elements to move away from each other. This force is greater than the force being applied to the braking elements by the braking member 28 therefor. This movement causes the friction pads 20 of the braking element 18 to engage a corresponding braking component, typically the brake drum, to prevent an associated wheel of the brake assembly from rotating.
[0056] Upon release of the engagement feature, the force being applied to the actuator lever 30 is released or otherwise becomes less than the biasing member 28 for the braking elements 18 . Through the biasing member, the braking elements move towards the actuator mechanism 10 and each other. This movement results in a force being applied to the strut members 32 , 34 , which in turn results in a force being applied to the actuator lever to return the lever to an original position.
[0057] It has been realized that the features of the present invention have resulted in drastically improved operating cycle of the parking braking assembly. Such improvements have resulted in an increased life span of the parking brake assembly upwards of 2, 4, 6 fold or more. Specifically, the braking assembly has achieved minimum required braking ability over an operating cycle of more than 20,000 cycles. It is also realized that the operating cycle of the braking assembly of the present invention may be substantially greater than 20,000 cycles, including greater than 40,000, 50,000, 75,000, 100,000 or ever greater than 125,000 cycles.
[0058] Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. Plural structural components can be provided by a single integrated structure. Alternatively, a single integrated structure might be divided into separate plural components. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such features may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention.
[0059] The preferred embodiment of the present invention has been disclosed. A person of ordinary skill in the art would realize however, that certain modifications would come within the teachings of this invention. Therefore, the following claims should be studied to determine the true scope and content of the invention. | The present invention is predicated upon improved vehicle brake assemblies, parking brake assemblies, parking brake actuators, or combinations thereof, having simplified attachment features, reduced friction and improved duty cycle over previously known devices. | 5 |
This is a division of application Ser. No. 034,171, filed Apr. 26, 1979, now U.S. Pat. No. 4,316,715.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to concrete screeds, and more particularly, open frame vibratory screeds.
2. Description of the Prior Art
A wide variety of vibrating concrete screeds are disclosed in the prior art. An open frame, vibrating screed is manufactured by the H. Compton Company of Conroe, Tex., and includes a plurality of pneumatic vibrators mounted at intervals on front and rear screed blades. This screed is fabricated in variable length sections, is translatable over a freshly poured concrete surface by a pair of winches and can be adjusted to provide a variable contour for the surface of the concrete being screeded. Another related concrete screed is manufactured by AWS Manufacturing, Inc. of Naperville, Ill. The AWS concrete screed also includes a wall mounting bracket attachment which is bolted to an end bracket of the screed and includes a single length of angle iron which engages the top and side surfaces of a 2×4 wall mounted guide rail. U.S. Pat. No. 4,030,873 (Morrison) rdiscloses a multi-element concrete screed having variable length elements and a rotating shaft which extends along the length of the screed for imparting uniform vibrations to the front and rear screed blades. All of the above described concrete screeds are vertically supported above opposing, parallel oriented side forms.
U.S. Pat. No. 3,110,234 (Oster) discloses a concrete screed having vertically adjustable blades which are translatable along parallel oriented rails. U.S. Pat. No. 3,435,740 (McGall) discloses a concrete screed including a hand operated winch for laterally translating the screed and a turnbuckle system for adjusting the concrete surface contour formed by the various sections of the screed.
U.S. Pat. No. 2,542,979 (Barnes) discloses a concrete screed having an inverted T-shaped screed blade and electric motor for imparting a vibratory motion to the screed blade.
U.S. Pat. No. 3,883,259 (Berg) discloses another concrete screed having parallel oriented blades and means for imparting vibratory motion to the blades.
The following U.S. patents disclosed other concrete screed configurations: U.S. Pat. Nos. 2,372,163 (Whiteman); 1,386,348 (Maxon); 2,866,394 (Smith); 3,008,388 (Nave); 4,073,593 (Storm); 3,095,789 (Melvin); 3,523,494 (Kraemer); 2,219,247 (Jackson); 3,113,494 (Barnes); 2,693,136 (Barnes) and 4,105,355 (King).
SUMMARY OF THE INVENTION
The present invention contemplates a vibrating concrete screed system including a fixed blade extension bracket, an adjustable blade extension bracket, a detachable guide bracket, a detachable pan float finisher and a center mounted winch attachment. Each of these attachments can be readily coupled to a screed which converts freshly poured concrete freshly poured concrete lying in an area between opposing side forms into a smooth, finished concrete surface. The screed of this system comprises a frame having first and second ends, front and rear screed blades coupled in a spaced apart relationship to the lower portion of the front and rear of the frame to shape the upper surface of the concrete, and first and second end brackets which are coupled to the first and second ends of the frame
The fixed blade extension bracket can be coupled to either or both ends of the screed and includes a front blade extension which is coupled in alignment with the front screed blade to extend the overall length of the front blade by a predetermined desired amount. The fixed blade extension bracket also includes a rear blade extension which is coupled in alignment with the rear screed blade to extend the overall length of the rear blade by a predetermined desired amount.
The adjustable blade extension bracket can be coupled to either one or both of the end brackets and includes horizontally adjustable front and rear blade sections, and means for coupling the front and rear blade sections to the first and second side members of an end bracket to permit the adjustable end bracket to be coupled at selected vertical positions to the end bracket while maintaining the front and rear blade sections in parallel alignment with the front and rear screed blades.
The detachable guide bracket functions to guide one end of the screed along a wall mounted, horizontally oriented guide member. The guide bracket includes a first vertically oriented side member, a second vertical oriented side member, means for detachably coupling the first and second side members to an end bracket of the screed, and guide means laterally extending from the first and second side members for contacting the guide member to maintain the screed at a predetermined desired vertical position as the guide means is laterally translated along the length of the guide member.
The detachable bottom pan is positioned between the first and second end brackets of the screed and includes a front edge which is coupled to the front screed blade and a rear edge which is coupled to the rear screed blade.
Certain embodiments of the screed of the present invention include first and second winches which are coupled to the first and second end brackets and include lines extending from the first and second winches which are coupled to a stationary object for exerting a traction force on the first and second end brackets of the screed when the lines are reeled in by the first and second winches. A detachable, center mounted winch may also be provided. The center mounted winch attachment includes a line extending from the winch to a stationary object for permitting the center mounted winch to exert a traction force on the central section of the screed to permit uniform translation of the entire length of the screed.
DESCRIPTION OF THE DRAWINGS
The invention is pointed out with particularity in the appended claims. However, other objects and advantages together with the operation of the invention may be better understood by reference to the following detailed description taken in connection with the following illustrations wherein:
FIG. 1 is a perspective view of a two section screed in accordance with the present invention.
FIG. 2 is a partial elevational view of the left hand portion of the screed illustrated in FIG. 1.
FIG. 3 is an enlarged perspective view of the means for adjusting the contour of the front and rear screed blades.
FIG. 4 is an enlarged view of the hardware utilized to join the blade sections of adjacent screed sections.
FIG. 5 illustrates the structure and positioning of the center mounted winch attachment.
FIG. 6 is a perspective view illustrating a blade extension bracket in accordance with the present invention, and indicating the manner in which the blade extension bracket is coupled to the screed.
FIG. 7 illustrates the adjustable blade extension bracket of the present invention and the manner of coupling this bracket to an end bracket of the screed.
FIG. 8 is a perspective view of a detachable guide bracket in accordance with the present invention.
FIG. 9 illustrates the manner of attaching the detachable guide bracket to an end bracket of the screed and the relative positioning of the guide bracket with respect to a wall mounted guide rail.
FIG. 10 illustrates a blade extension bracket having a shorter length blade extension than the blade extension bracket illustrated in FIG. 6.
FIG. 11 is a partial sectional view of the adjustable blade extension bracket shown in FIG. 7.
FIG. 12 is an elevational view of the screed illustrated in FIG. 1, taken along section line 12--12.
FIG. 13 is a view from above of the screed illustrated in FIG. 12, taken along section line 13--13.
FIG. 14 is an enlarged view of a section of the screed shown in FIG. 13, particularly illustrating the structure and relative orientation of the truss members of the screed.
FIG. 15 is a sectional view of the screed illustrated in FIG. 12, taken along section line 15--15, particularly illustrating the manner in which the detachable bottom pan is coupled to the front and rear screed blades.
FIG. 16 illustrates the detachable pan float finisher of the present invention.
FIG. 17 is a view from above of the adjustable extension bracket shown in FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In order to better illustrate the advantages of the present invention and its contributions to the art, a preferred hardware embodiment of the inventive system will now be described in some detail.
Referring now to FIGS. 1 and 2, the vibrating concrete screed which forms the primary element of the screed system will be described. In many figures numerous support structures have been delected in the interest of more clearly illustrating other elements of the invention. The specific configuration of the open frame support structure will be fully described in connection with FIGS. 12, 13 and 14.
A horizontally oriented air transport pipe 10 extends between first and second end brackets 12 and 14. Two L shaped blades coupled back to back form a Tee-shaped front screed blade 16. An L-shaped rear screed blade 18 is also coupled to the first and second end brackets 12 and 14.
In the preferred embodiment the screed is fabricated in 5 foot and 71/2 foot lengths, any combination of which can be joined together to form a screed having a length reasonably close to the desired length.
FIG. 4 illustrates the manner in which a splice plate and a plurlity of securing means such as nuts and bolts may be used to couple together abutting ends of each screed blade section.
FIG. 3 illustrates the structure utilized to coupled adjacent sections of air transfer pipe 10 to form a single structural element. Air transfer pipe 10 forms an air tight conduit which supplied a source of air under pressure along the entire length of the screed. The air transfer pipe junction illustrated in FIG. 3 comprises a threaded coupling unit 20 having left hand threads on one end and right hand threads on the other end which is rotatably adjusted to provide the desired angle of incidence between adjacent screed section. This adjustment provides the desired contour on the upper surface of the concrete being screeded. A jam nut 22 locks coupling unit 20 in the desired position.
Referring now to FIGS. 1 and 2, a high volume air compressor unit is coupled by a crow's foot coupling unit 24 to inline lubricator 26. An air control valve 28 and an air pressure gauge 30 are coupled between coupling unit 24 and filter 26. Lubricator 26 and its associated hardware is detachably coupled to air transfer pipe 10 by a pair of spring clips of the type indicated by reference number 32. A flexible air hose 34 is coupled at one end to lubricator 26 and at the other end to air transfer pipe 10 by crow's foot coupling unit 36.
A plurality of penumatic vibrators are coupled at intervals along the length of front screed blade 16 and rear screed blade 18. The pneumatic vibrators are coupled to the vertical face of rear screed blade 18 and to the rear horizontally oriented face of front screed blade 16. An air hose, such as air hose 40, couples each vibrator unit to the source of air under pressure within air transfer pipe 10. The vibrators are generally staggered front to back and are coupled at 30 inch intervals. A vibrator is coupled to the front and rear screed blade 30 inches from both end brackets 12 and 14 to maximize vibration fo the scrred in the vicinity of the side forms. Each air vibrator unit 38 includes a vertically displaceable piston and a pair of air discharge ports in the side of the cylinder wall. The piston within each cylinder vibrates at between 6000 to 8000 cycles per minute when air at approximately 40 PSI is supplied. Air vibrator units of the type used in connection with the present invention are well known to those skilled in the art and are commercially available.
The complete screed unit is translated along the upper surface of opposing side forms 42 and 44 by actuation of winches 46 and 48. These winches can be power driven or manually operated devices. A cable 50 from each winch passes around a pulley 52 which is coupled by bolt through the vertical face of front screed blade 16 to the front vertically oriented member of end bracket 12. The free end of cable 50 is coupled to a stationary object generally aligned with side form 42.
To prevent bowing of the central portion of a screed having a length around 60 feet or more, a center mounted winch assembly of the type depicted in FIG. 5 is generally utilized. A center mounting bracket 54 of a configuration virtually identical to end brackets 12 and 14 is coupled at the junction between two adjacent screed units in the center of the assembled screed. An additional winch 56 is coupled to the upper portion of bracket 54. The cable extending from winch 56 passes through a pulley in a manner similar to that described in connection with the pulleys for outboard winches 46 and 48. Workmen operate winches 46, 48 and 56 at an equal rate to uniformly translate the screed in the desired direction to prevent bowing of the central portion of the screed.
Since it is frequently desirable to more precisely tailor the length of a concrete screed to match the distance between side members 42 and 44 than is permitted by the previously described 5 foot and 71/2 foot screed sections, blade extension brackets of various fixed lengths have been provided as is illustrated in FIG. 6 and 10. To incorporate a blade extension bracket 58 into the screed, one or both of the end brackets 12 and 14 are removed from the screed. Extension bracket 58 is then coupled by securing means such as nuts and bolts to the front and rear screed blades. Each extension bracket includes a front blade extension 60 and a rear blade extension 62. As can be seen from FIG. 6 and 10, the length of the front and rear blade extensions can be fabricated in any desired length. In the system of the preferred embodiment, three blade extension brackets having lengths of 6, 12 and 18 inches are provided. Blade extension bracket 48 also includes a horizontally oriented strut 64 which extends between the end portions of blade extensions 60 and 62 to maintain a predetermined fixed spacing therebetween. Angled support struts 66 and 68 are coupled respectively to the outer end of front blade extension 60 and rear blade extension 62 and to the vertically oriented members of blade extension bracket 48. If desired, vibrators may be coupled to the blade extension bracket.
Referring now to FIGS. 11 and 17, a vertically and horizontally adjustable blade extension bracket 70 will be described. A bracket of this type is particularly desirable when it is necessary to form a step or sidewalk adjacent to the roadbed or warehouse flooring which is being formed by the remainder of the screed. The adjustable blade extension bracket 70 is coupled to the parallel oriented, vertically extending side members 72 and 74 of end bracket 12. Bracket 70 can be divided generally into a telescopically adjustable first section 76 which permits adjustment of the lateral extension of section 76 with respect to end bracket 12. A second vertically adjustable section 78 permits the entire unit to be adjustably secured to side members 72 and 74 of end bracket 12. Section 78 includes a pair of horizontally oriented channel members 80 and 82 which are dimensioned to permit the two telescopically adjustable legs of section 76 to be readily laterally translatable within the interior of sections 80 and 82. Securing means in the form of an adjustable bolt, such as bolt 84, are provided in the sides of channels 80 and 82 to clamp section 76 in the desired lateral position. The horizontal distance between the interior portions of channels 80 and 82 is just sufficient to permit them to be fitted within the interior walls of side members 72 and 74 of end bracket 12.
A horizontally oriented support strut 86 is of a length equal to the horizontally oriented support strut 88 of end bracket 12. The distance between the interior surfaces of channels 80 and 82 is equal to the overall width of strut 88. Pairs of parallel aligned steel plates, such as plate 90 are coupled by securing means, such as a plurality of nuts and bolts, at one end to each vertically extending strut 92 of bracket 70. A second plurality of securing means, such as another set of nuts and bolts, passes behind side member 72 and serves to hold the two parallel aligned steel plates 90 together around side member 72. A third set of bolts, such as bolt 94, are threadably coupled to the exterior of steel plate 90 and when tightened serve to clamp bracket 70 in a predetermined desired vertical position along side members 72 and 74. In the above described manner structure is provided which permits vertical and lateral adjustment of the adjustable blade extension bracket 70.
Referring now to FIGS. 8 and 9, a detachable guide bracket forming a portion of the system of the present invention will now be described. Guide bracket 96 includes vertically oriented members 98 and 100 and a horizontal member 102 from which a group of three lips, such as lip 104, extend to form a three-sided rectangular aperture for accomodating the upper horizontally oriented strut of end bracket 12.
A pair of parallel oriented rectangular steel plates, suh as plate 106, are secured to the lower portion of each side member 98 and 100. As guide bracket 96 is rotatably fitted to end bracket 12, each pair of plates coupled to the lower portion of side members 98 and 100 slip around the lower portion of the side members of end bracket 12. Securing means, such as a pair of nut/bolt units 108, is provided to draw the parallel plates together to securely clamp guide bracket 96 to end bracket 12.
Additional bracket structure of the type illustrated extends outward from the side of guide bracket 96 and includes a pair of curved, horizontally oriented guide faces 110 and a pair of curved, vertical oriented guide faces 112. Guide faces 110 and 112 are configured to slide along the exposed horizontal and vertical faces of a 2×4 guide member 114 which is secured to a wall 116. The weight of one end of the screed is thus supported by guide rail 14 as the screed is translatable along the length of the concrete which is being shaped.
Referring now to FIGS. 12, 13, 15 and 16, a detachable aluminum pan float finisher is disclosed. Pan 118 includes a plurality of apertures in alignment with the horizontal sections of the front and rear screed blades. Securing means are passed through the plurality of apertures in order to couple pan 118 to the lower surface of front and rear screed blades 16 and 18. The pan float finisher includes upward curved front and rear end sections to assist in smoothing freshly poured concrete.
Referring now to FIGS. 12, 13 and 15, pan float finisher 118 is shown coupled to the screed. These figures together with FIG. 14 also clearly illustrate the totality of the network of struts which form the open frame for the screed of the present invention. Similar strut elements in each figure are referred to by the same letter/number designator, e.g. strut A1 in FIG. 12 corresponds to strut A1 in FIG. 14. Each strut is coupled at both ends by welded junctions to the remainder of the screed and to the various adjacent other struts.
It will be apparent to those skilled in the art that the disclosed vibrating concrete screed system may be modified in numerous ways and may assume many embodiments other than the preferred forms specifically set out and described above, Accordingly, it is intended by the appended claims to cover all such modifications of the invention which fall within the true spirit and scope of the invention. | A screed includes a triangular truss frame having first and second ends and a top support member forming the apex of the triangular truss. Front and rear screed blades are coupled in a spaced apart relationship to the lower portion of the front and rear of the frame. The screed includes a detachable screed blade extension bracket which is coupled to the top support member and to the front and rear screed blades. The detachable screed blade extension bracket includes a bracket frame, front and rear blade extension elements which are coupled to the bracket frame and aligned respectively with the front and rear screed blades for extending the effective length of the blade by a predetermined, desired amount. The detachable end bracket extends the effective length of the front and rear screed blades without extending the length of the top support member or the triangular truss frame of the screed. | 4 |
RELATED APPLICATIONS
[0001] The present application is related to U.S. Provisional Patent Application, Ser. No. 60/546,812, filed on Feb. 23, 2004, which is incorporated herein by reference and to which priority is claimed pursuant to 35 USC 119.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains generally to illuminating optical systems, AND more particularly, to a nighttime, long-range, portable illuminating device having an integrated telescopic imaging and viewing systems.
[0004] 2. Description of the PriorArt
[0005] Handheld lighting devices with focused beams or spotlights or searchlights, whether battery-powered or line-powered, are commonly used by military, law enforcement, fire and rescue personnel, security personnel, hunters and recreational boaters among others for nighttime surveillance in any application where a high intensity spotlight is required. The conditions of use are highly varied, but generally require the light to deliver a desired field of view at long distances, be reliable, durable and field maintainable in order for it to be practically used in the designed applications. Typically the light is hand carried and must be completely operable using simple and easily access manual controls which do not require the use of two hands.
[0006] In prior art xenon short-arc searchlights or illumination systems, whether handheld, portable or fixed mounted, the luminance distribution of the arc has been positioned facing in the direction of the beam (cathode to the rear), to provide a uniform beam pattern when the arc is at the focal point of the parabolic reflector. When the luminance distribution of the arc is positioned in this manner, a majority of the light output is collected in the low magnification section of the reflector and in a slightly divergent manner in the far-field. When the beam is diffused into a flood pattern, a large un-illuminated area or “black hole” is projected. Reversing the lamp position so that the full luminance distribution of the arc is in the high magnification section of the parabolic reflector produces a more concentrated beam in the near- and far-field and hence greater range can be achieved. Additionally, when the beam is diffused into a flood pattern no characteristic “black hole” of prior art configurations is produced. When the arc is moved slightly beyond (or slightly rearward of) the reflector's focal point, the combination of a placing all available light in the high magnification section of the reflector and collecting it in a slightly convergent manner produces roughly twice the operating range as a conventional anode-forward device.
[0007] A device which remedies the foregoing limitations, but which is still only an illumination unit with no enhanced viewing components is shown in Jigamian, U.S. Pat. No. 6,702,452 (2004), and U.S. patent applications 20050007766 (2005), 20040042211 (2004), 20040027824 (2004), which are incorporated herein by reference.
[0008] Telescopic viewing systems also employing imaging and night vision capability are well known. However, a need exists, especially in military and law enforcement applications, for a long-range, portable system capable of illuminating and observing objects at a range of approximately 400 meters and farther, using visible or infrared illumination and for providing for the possibility of image real time processing in the portable illumination unit.
BRIEF SUMMARY OF THE INVENTION
[0009] In one aspect, the invention is a compact device that can illuminate objects much farther than the eye can see or reliably resolve. The ability to clearly observe a scene at ranges of approximately 400 meters and farther at nighttime or in low-light conditions or other situations of impaired visibility gives the user a significant operational advantage. It is contemplated that such a system will be beneficial in military, law enforcement, border-patrol, security, and maritime vessel applications, and other applications where a portable, compact device of this kind is desired.
[0010] Separate systems for illuminating from a great range while simultaneously observing using a different apparatus, such as a telescopic viewing and imaging system, can be cumbersome, unwieldy and difficult to operate. One particular problem is finding and maintaining alignment and focus on a particular object that is separately illuminated by another system. Other advantages become apparent particularly in infrared illumination applications. More specifically, focusing with infrared light requires more precise alignment angles for a lamp and a lens as just a couple of degrees difference will result in a loss of a large amount of available light energy.
[0011] The present invention is also characterized as a compact, handheld, portable device that can illuminate objects at distances greater than the naked eye can reliably see. The device further provides illumination in either the visible spectrum or infrared spectrums. A telescopic lens system integrated with the illumination system has sufficient capability to view objects from a great distance in both the visible and infrared spectrums. The telescopic lens system can alternatively be applied to a digital camera system. More specifically, the digital camera system may contain an image sensor, such as a charge-coupled device (CCD), and a means to display an image such as a LCD display. The invention alternatively includes an eyepiece lens such that a user may choose to view a display screen or use the eyepiece lens to optically observe the field of view. Because the image is digital, the invention allows for the possibility of real time imaging processing in the portable device, so that the displayed image can be artificially enhanced according to the control of the user to optimize visualization of the image or a selected part thereof. The invention also includes the ability to transmit image data to remote receivers as part of a wireless battlefield.
[0012] The device of the present invention has a light source or a lamp, such as a xenon arc lamp or other plasma lamp; or alternatively the device comprises a high intensity discharge lamp (HID) such as a mercury vapor, metal halide or high pressure sodium lamp. The device of the invention is further characterized in that light energy is produced from a highly concentrated plasma ball, or illumination source, and precisely radiated about a reflector's optical axis of symmetry, wherein light waves can achieve great illumination distances. Alternatively, if a plasma lamp is used, the plasma lamp will have circuitry associated with it to obtain proper voltages for creating and maintaining a glowing plasma. Also, the device including the lamp will have a mechanical configuration including a lamp holder that allows for relatively quick replacement in the field while maintaining the precise alignment necessary for long-range operation.
[0013] Also, the lamp is mounted within the searchlight so that the anode of the lamp is in the rearward position relative to the direction of a beam projected by the searchlight so that the field of illumination of the beam is slightly convergent and more concentrated and therefore delivers a much longer range of operation. This configuration will prevent the “black hole” effect associated with other configurations such as cathode to the rear.
[0014] The device of the invention further includes a telescopic sight having one or more objective lenses. It is contemplated that one objective lens could be used for both visible light and infrared applications or separate lenses provided depending on the application. The device of the invention also includes other optical elements as needed for focusing and collimating light. The searchlight can be highly collimated to deliver a useful spotlight over a mile away. According to one embodiment, an eyepiece is employed by a user to view an image plane. In an alternative embodiment, an image sensor such as a charge-coupled device (CCD) having a pixel array is employed. The image sensor will accumulate pixel data as electrical charge and transfer the pixel data to storage locations during a frame cycle. Additional circuits will convert the pixel data to a video signal that can be displayed on a video screen of the device. The video signal may also be transmitted to remote locations. The image sensor will either solely produce monochrome images or color signals may be constructed from the image sensor.
[0015] In yet another aspect, the present invention may be characterized as a compact self-contained device having illuminating, telescopic viewing and imaging capabilities, the device comprising: a searchlight housing having a top portion and a side portion; a view finder having an eyepiece and having an adjustable position with respect the searchlight housing, wherein the view finder is pivotable about a position with respect to the top portion of the searchlight housing. In this manner, the view finder has a stowed position and an adjustable deployed position. The device also includes a video display having an adjustable position with respect the searchlight housing, wherein the video display is pivotable about a position with respect to the side portion of the searchlight housing; and a telescopic lens assembly integrally connected to the searchlight housing, wherein the telescopic lens is configured to receive light from a distant scene that is illuminated by the device.
[0016] The device of the invention optionally provides that the view finder, video display and the telescopic lens assembly are modular components for ease of manufacture and replacement of the components. As in other embodiments described herein, telescopic lens assembly is capable of magnifying objects in the distant scene up to approximately 20× and farther. The video display may alternatively be an LCD display. A filter may also be provided, positioned forward of the searchlight housing for blocking wavelengths of light up to infrared wavelengths, namely a low pass filter with a cutoff at the visible frequency and higher. In this way the device becomes an infrared searchlight and telescope.
[0017] While the apparatus and method has or will be described for the sake of grammatical fluidity with functional explanations, it is to be expressly understood that the claims, unless expressly formulated under 35 USC 112, are not to be construed as necessarily limited in any way by the construction of “means” or “steps” limitations, but are to be accorded the full scope of the meaning and equivalents of the definition provided by the claims under the judicial doctrine of equivalents, and in the case where the claims are expressly formulated under 35 USC 112 are to be accorded full statutory equivalents under 35 USC 112. The invention can be better visualized by turning now to the following drawings wherein like elements are referenced by like numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1A is a front perspective view of the searchlight as seen from the front left side of the searchlight and showing the viewing components deployed for operation.
[0019] FIG. 1B is a rear perspective view of the searchlight as seen from the front left side of the searchlight and showing the viewing components deployed for operation.
[0020] FIG. 2 is a schematic block diagram of the viewing and display portions of the system of the present invention capable of long-range illumination and observation.
[0021] The invention and its various embodiments can now be better understood by turning to the following detailed description of the preferred embodiments which are presented as illustrated examples of the invention defined in the claims. It is expressly understood that the invention as defined by the claims may be broader than the illustrated embodiments described below.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Now referring to FIGS. 1A and 1B , a compact, handheld device 10 of a preferred embodiment of the present invention is illustrated in front and rear perspective view. Eyepiece viewer 12 has a deployed and a stowed position, which is shown in FIGS. 1A and 1B in the stowed position. Eyepiece viewer 12 is optically coupled to the telescopic lens assembly 14 and can be rotated upward to be deployed at a user-selected angle of convenience or rotated downwardly to lie in a flush configuration within a receiving cavity 13 defined in body 11 of device 10 . The actual image which is being optically received by telescopic lens assembly 14 can be directly viewed by the user through eyepiece viewer 12 .
[0023] Similarly, telescopic lens 14 has deployed and stowed positions. Lens assembly 14 rotates out of a cavity 24 defined in body 11 for flushly receiving lens assembly 14 as a protective door 17 also moves or rotates out. The mechanical linkage by which such movements can be realized are conventional and not further detailed here. Lens assembly 14 will be forwardly directed when deployed and will be substantially aligned with or parallel to the optical axis of illumination head 15 or the beam of the device 10 . Although lens assembly 14 will be normally aligned to coincide with the beam position at the preferred range, e.g. 400 m, it is to be understood that other ranges can be accommodated and a mechanism to allow variable alignment of lens assembly 14 in the field to virtually any beam position can be provided using ordinary design principles and modifications.
[0024] Lamp housing 15 contains a lamp and reflector apparatus internally (not shown). Rotatable bezel 16 is used to vary the beam spread of the illumination device of the present invention by effecting relative movement of the reflector with respect to the light source within lamp housing 15 . The details of lamp housing 15 and its lamp and reflector apparatus are detailed in the incorporated U.S. Pat. No. 6,702,452 (2004), and U.S. patent applications 20050007766 (2005), 20040042211 (2004), 20040027824 (2004). Filter 18 is mounted in bezel 16 and is selectively included to filter out undesired wavelengths of light, e.g. to provide an infrared beam only or other selected portion or portions of the spectrum.
[0025] Video display 22 allows the user to selectively view an image scene or a selected portion of the scene captured by lens assembly 14 . Video display 22 also has deployed and stowed positions. Display 22 rotates out of a conforming cavity 19 defined in body 11 of device 11 , which allows display 22 to remain flushly within the envelope of body 11 for protection and storage. When deployed, display 22 swings out from body 11 and can be oriented on a conventional swivel connection to be angularly inclined at an arbitrary user-selected angle for convenient viewing. Display 22 may be any type of video display now known or later devised, including LCD, plasma displays, or LED displays.
[0026] Referring now to FIG. 2 , a simplified schematic of a circuit 20 of the present invention is shown. Long-range illuminator 10 has an optical filter 18 and projects a high intensity beam 36 of light. System 20 may be combined with separate or interchangeable telescopic lens assemblies 14 for infrared and visible light; or a single lens assembly 14 can be configured to handle both modes. Lens assembly 14 has objective lens 42 and collimating lens 44 , as well as focusing lens 52 . Although single lenses have been reference, it must be expressly understood that lens assemblies can be employed in each case and that the optical arrangement in device 10 can be readily modified to assume other configurations according to conventional design choices.
[0027] A user 55 can view the distant scene focused on image plane 54 through eyepiece 24 . Partially silvered mirrors 46 and 48 are used to send the image to a collecting lens 40 and detector or charge coupled device 58 , which is employed to capture a two dimensional image. In the event that device 58 is an analog imaging camera, its output may be coupled to analog-to-digital converter 62 . A video output 64 from converter 62 is produced that may be transmitted by other appropriate digital transmission equipment to remote locations. The video signal may also be bidirectional so that the same digital transmission equipment coupled to device 10 could receive information, including graphic information from a remote site and display the same on display 22 . The reconstructed digital image captured by lens assembly 14 is viewed on video display 22 .
[0028] It must be understood that additional circuitry may be included to process the digital image produced by detector 58 and/or converter 62 . In the case of an infrared image, the only image which will be visible will be displayed on display 22 after being converted into a visible video signal by display 22 . Display 22 or detector 22 may include circuitry or digital processing capability according to well known conventional principles to select, edit, enhance or reduce various aspects of the received visual image. For example, false coloring of an image to represent the temperature of various portions of the image or false coloring to exaggerate the contrast of some portions with surrounding portions can readily be included. In addition, variable electronic magnification or zoom can be added to the variable optical magnification of lens assembly 14 subject to user control. Motion detection of the image can also be included, whereby any portion of the image which is moving relative to other portions of the surrounding image is highlighted or falsely colored to be readily visually identified.
[0029] Although in one embodiment image processing is contemplated as being performed in real time in the device 10 , it is also within the scope of the invention, where output 24 is bidirectional, that image processing can be performed at a remote station and then returned in modified form to device 10 . Such remote image processing may include selective mixing with other images derived from other devices 10 in the field or combined with information generated or collected at the remote site. In such a situation, display 22 could be modified to be an input/output device, such as a touch screen. In this manner the displayed scene on display 22 from wherever it may be derived, allows for interactive input by the user in the field. The remote fire control command center may, for example, process the image from device 10 for suspected targets, one or several of which will then be selected by touching the screen by the user in the field, which selection is then communicated back to the remote fire control command center, which in turns directs appropriate fire control to other units in the theater. Device 10 can thus be used in this manner of one of many interactive detection and input devices in an integrated battlefield fire control system.
[0030] Many alterations and modifications may be made by those having ordinary skill in the art without departing from the spirit and scope of the invention. Therefore, it must be understood that the illustrated embodiments have been set forth only for the purposes of example and that it should not be taken as limiting the invention as defined by the following claims. For example, notwithstanding the fact that the elements of a claim are set forth below in a certain combination, it must be expressly understood that the invention includes other combinations of fewer, more or different elements, which are disclosed in above even when not initially claimed in such combinations.
[0031] While the particular Portable Long-range Searchlight with Telescopic Viewing and Imaging Systems as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.
[0032] Insubstantial changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements. | A portable searchlight with a focused beam operating both in the infrared and visible portions of the spectrum with a range of approximately 400 meters includes telescopic lens system integrated with an illumination system. The beam of the searchlight and the telescopic lens are automatically aligned to both focus on the distant object. The telescopic lens system is combined with a digital camera system and an LCD display. The searchlight includes an eyepiece lens so that a user may choose to either view a display screen or use the eyepiece lens to optically observe the field of view. Because the image is digital, the invention allows for the possibility of real time imaging processing in the portable device and/or the ability to transmit image data to remote receivers. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a tracer control system, and more particulary to a tracer control system which automatically changes the clamp level by a predetermined value for each working to perform clamp tracing continuously from rough to finish machining.
2. Description of the Prior Art
In clamp tracing according to a conventional tracer control system, for example, as shown in FIG. 1, a limit switch LS is provided at the position of a certain depth D of a model MDL where clamp tracing is desired to effect (which position will hereinafter be referred to as a clamp level); when the limit switch LS is turned ON by the movement of the tracer head, a feed in the direction of depth of the model MDL is stopped and a stylus is moved horizontally without contacting the model MDL: and tracing is re-started from the position where the stylus moves into contact with the model MDL. Upon completing of one machining operation, the position of the limit switch is changed, for example, by a predetermined depth of cut ΔD to a position LS', where the same clamp tracing as mentioned above takes place. By repeating such operation, the configuration of the model MDL is finally traced down to its bottom. Thus, since the conventional system calls for the limit switch, the reliability of the tracing operation is relatively low because of the mechanical operation of the limit switch, and since the position of the limit switch must be changed for each working operation, it is difficult to continue working operations from rough to finish machining without a break and the working time is long as a whole.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a tracer control system in which data on the clamp level is prestored in a memory and clamp feed points are controlled in accordance with the data to enable continuous tracing from rough to finish machining, thereby reducing the machining time.
Briefly stated, in the tracer control system of the present invention, there are provided an input unit for entering data defining the tracing operation, a memory for storing the data and a processor for reading out the data from the memory to control respective parts of a control device. The processor reads out from the memory data concerning clamp profiling and controls the clamp level to change by a predetermined value for each machining operation, thereby permitting repetitive tracing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is explanatory of conventional clamp profiling;
FIG. 2 is a block diagram illustrating an embodiment of the present invention;
FIG. 3 is explanatory of an example of the tracing path; and
FIG. 4 is a flowchart explanatory of the operation of the embodiment shown in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 is a block diagram illustrating an embodiment of a tracer control system of the present invention. In FIG. 2, reference characters DG and IND respectively indicate a displacement calculation circuit and an indexing circuit which are supplied with displacement signals ε x , ε y and ε z from a trace head TR; ARN and ART designate velocity control circuits; ADD identifies an adder; DC denotes a distribution circuit; COMP represents a comparator; GC shows an analog gate circuit; DRVX, DRVY and DRVZ refer to amplifiers; MX, MY and MZ indicate servo motors; PCX, PCY and PCZ designate position detectors; MDL identifies a model; ST denotes a stylus; CT represents a cutter; W shows a work; MAC refers to a tracing machine; CNTX, CNTY and CNTZ indicate reversible counters which count pulses from the position detectors to indicate the current position of the stylus; CLP designates a clamp feed command circuit; OPP identifies an operator panel; RS denotes a setting dial for velocity or the like; BT1 and BT2 represent push buttons; KB shows a keyboard; DSP refers to a display; DI indicates a data input unit; MEM designates a memory composed of a data memory part M1 and a control program part M2; DO identifies a data output unit; CPU denotes a processor; DA1 and DA2 represent D-A converters; and MAN shows a manual operation control circuit.
The stylus ST held in contact with the surface of the model MDL is fed by the servo motors and the displacement calculation circuit DG derives a composite displacement signal ε=√ε x 2 +ε y 2 +ε z 2 from displacement signals ε x , ε y and ε z corresponding to the displacement of the stylus ST, and the indexing circuit IND provides direction-of-displacement signals sinθ and cosθ. The composite displacement signal ε is applied to the adder ADD to obtain a difference Δε between the composite signal ε and a deflection signal ε 0 , which difference Δε is provided to the velocity control circuits ARN and ART to obtain a normal-direction velocity signal V N and a tangential-direction velocity signal V T . These signals V N and V T are applied to the distribution circuit DC to yield a velocity command signal in accordance with the direction-of-displacement signals sinθ and cosθ, and the velocity command signal thus obtained is supplied to the analog gate circuit GC. The velocity command signal is then provided to that one of the amplifiers DRVX, DRVY and DRVZ which is selected by the analog gate circuit GC. By the velocity command signal, the servo motor corresponding to the selected amplifier is driven to feed the cutter CT and the tracer head TR in ganged relation to each other. Since the operations described above are already well-known in the art, no detailed description will be given.
In the present embodiment, tracing operation data including data on the clamp level is entered from the keyboard KB or the like for storage in the memory MEM, from which the data is read out as the tracing operation proceeds, and in accordance with the data, the tracing path including the clamp level is controlled. That is, the present embodiment permits continuous machining operations from rough to finish machining by automatically changing the clamp level for each machining operation in accordance with the stored data concerning the clamp level, without involving such a manual operation as is needed in the prior art. As the input data, use can be made of such, for example, as shown in the following table.
TABLE 1______________________________________ITEM SYMBOL CODE______________________________________Mode (See Table 2) A01Deflection ε.sub.0 A02Approach Axes X, Y, Z A03Direction of Approach +, - A04Velocity of Approach V.sub.AP F1Direction of Tracing +, - A05Velocity of Tracing V.sub.TF F2Direction of Pick Feed +, -Velocity of Pick Feed V.sub.PF F3Quantity of Pick Feed P A06Tracing Turning Position L.sub.P X1Tracing Turning Position L.sub.N X2Tracing End Position L.sub.TE Y1Automatic Return ON, OFF A07Velocity of Automatic Return V.sub.AR F4Automatic Return Position L.sub.RP Z1Clamp Level Initial Position C.sub.PL C01Clamp Level Variation ΔC.sub.PL C02Clamp Level Final Position C.sub.PLE C03______________________________________
TABLE 2______________________________________Mode Sub-Mode______________________________________1 Manual Tracing2 Both-Ways Tracing 45° Tracing3 One-Way Tracing4 360 Deg. Tracing Axial-Direction Pick Z-Axis Pick5 Partial Tracing6 Three-Dimensional Tracing7 Clamp tracing______________________________________
Turning now to FIG. 3, the tracer control by the present invention will be described. In FIG. 3, the tracing turning points L P and L N are X1 and X2; the pick feed P is AO2; the tracing end position L TE is Y1; the automatic return position L RP is Z1; and the clamp level initial position C PL is CO1; and the stylus ST is controlled by the data on the velocity and direction of tracing so that it approaches a point a from a starting point A and traces the model surface following a route [a-b-c- . . . u-v] to effect clamp tracing in the sections a to b, c to d, . . . t to u and then automatically returns from the tracing end position Y1 to the automatic return position Z1. In this case, the tracing operation is controlled following such a flowchart as depicted in FIG. 4.
Upon depression of an approach button (not shown), the processor CPU reads out data on the axis, direction and velocity of approach from the memory MEM and provides a signal via the data output unit DO to the analog gate circuit GC to activate the amplifier DRVZ, causing the servo motor MZ to lower the tracer head TR and the cutter CT. The velocity in this case can be determined by data F supplied via the data output unit DO to the D-A converter DA2.
Before the stylus ST is brought into contact with the model MDL, the displacement signals ε x , ε y and ε z are zero, and accordingly the difference signal Δε remains to be equal to the deflection signal ε 0 . When the composite displacement signal ε has become equal to the deflection signal ε 0 as a result of contacting of the stylus ST with the model MDL, the comparator COMP detects that Δε=0, and applies an approach end signal AE to the data input unit DI. The approach end signal AE is read out by the processor CPU to detect the completion of approach, and then tracing is started.
Upon start of tracing, the processor CPU reads out data such as mode, the deflection, the direction and velocity of tracing, starting tracer control. The deflection data is converted by the D-A converter DA1 into an analog deflection signal ε 0 for input to the adder ADD, and the servo motor MX is driven in a direction following the direction-of-tracing data. Further, the processor CPU reads out the clamp level initial position C PL from the memory MEM and compares it with the content of the reversible counter CNTZ representing the current position of the stylus ST.
When it is detected by the comparison that the content of the reversible counter CNTZ and the clamp level initial position C PL match with each other, the processor CPU sends out, by an interrupt operation, a start signal CL via the data output unit DO to the clamp feed command circuit CLP to start it and, at the same time, changes over the gate circuit GC to pass on a clamp feed command signal from the clamp feed command circuit CLP to a predetermined one of the servo motor. By this operation, the stylus ST does not trace but instead is moved in a horizontal direction, and clamp feed takes place at a predetermined level position.
During the clamp feed, since the displacement signals ε x , ε y and ε z of the stylus ST are zero, the difference signal Δε remains equal to the deflection signal ε 0 , but when the stylus ST gets into contact with the model MDL, the composite displacement signal ε becomes equal to the deflection signal ε 0 , with the result that the difference signal Δε becomes zero. When detecting that Δε=0, the comparator COMP applies the approach end signal AE to the data input unit DI, and the processor CPU reads out this approach end signal AE to detect that the stylus ST has been brought into contact with the model MDL by the clamp feed. Then, the processor CPU stops the clamp feed command circuit CLP via the data output unit DO and changes over the gate circuit GC to stop the clamp feed, restoring the aforesaid tracing operation.
Further, the processor CPU reads out the tracing turning position L P and L N from the memory MEM and compares them with the content of the counter CNTX. For example, in tracing of direction "-", when the content of the reversible counter CNTX and the tracing turning position L N match with each other, the axis is changed over the processor CPU reads out data such as the direction, velocity and quantity of pick feed P to control the pick feed. When the content of the reversible counter CNTY comes to be equal to the pick feed P from the start of the pick feed operation, the processor CPU causes the stylus ST to turn, that is, controls it to trace in the direction +. Further, the processor CPU checks whether the stylus ST has reached the tracing end position or not, and when detecting that the tracing end position L TE is reached during the pick feed, the processor CPU reads out the data of the automatic return, the automatic return velocity and the automatic return position L RP from the memory MEM. Since the automatic return is ON, the servo motor MZ is driven and when the content of the reversible counter CNTZ has come to indicate the automatic return position L RP , one tracer control operation comes to an end.
In the event that repetitive tracing has been preset by the input from the keyboard KB, the processor CPU returns the stylus ST by known positioning control to the approach starting point A immediately following the automatic return operation, carrying out the clamp tracing again. In this case, the clamp level is C PL +ΔC PL which is the sum of the aforesaid clamp level position C PL and a clamp level variation ΔC PL prestored in the memory MEM in consideration of the cutting performance of the tool used. Since the repetitive clamp tracing can be effected by automatically changing the clamp level for each working operation as described above, it is possible to achieve machining operations continuously from rough to finish machining, thereby markedly reducing the machining time.
The tracing turning positions L P and L N , the tracing end position L TE , the automatic return position L RP , the pick feed P, the clamp level initial position C PL , the clamp level variation ΔC PL and the clamp level final position C PLE may also be obtained by setting in the memory MEM the contents of the reversible counters when the stylus ST is shifted to its respective positions in a manual feed mode, instead of entering the data from the keyboard KB.
Also during the tracing operation the tracing path including the clamp level can be corrected by reloading the data in the memory MEM. For example, the data in the memory MEM are read out therefrom and displayed on the display DSP and the data are corrected and reloaded by the manipulation of the keyboard KB. Thus, the clamp tracing start position, i.e. the clamp level initial position C PL , the clamp level variation ΔC PL and the clamp level final position C PLE can be corrected with ease.
In the foregoing embodiment, all data defining the tracing operation are prestored in a memory for controlling the tracing path including the clamp feed path, but in the present invention, all the data need not always be prestored; for example, the tracing turning position and the like may also be controlled by a limit switch as in the prior art.
As has been described above, the present invention permits repetitive clamp tracing by automatically changing the clamp level by a predetermined value for each working in accordance with prestored data on the clamp tracing and consequently machining operations can automatically be carried out continuously from rough to finish machine, resulting in the working time being greatly reduced.
It will be apparent that many modifications and variations may be effected without departing from the scope of the novel concepts of this invention. | In a system which performs tracer control by calculating the direction and the velocity of tracing through utilization of signals from a tracer head tracing the model surface, there are provided an input unit for entering data defining the tracing operation, a memory for storing the data and processor for reading out the data from the memory to control respective parts of a control device. Data concerning clamp tracing is read out by the processor to change the clamp level by a predetermined value for each working, thereby performing repetitive clamp tracing. | 8 |
RELATED APPLICATION
[0001] Priority is claimed herein under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 60/835,635, filed Aug. 4, 2006, entitled “PROCESSES FOR THE PREPARATION OF 4-CHLORO-3-METHYL-5-(2-(2-(6-METHYLBENZO[D][1,3]-DIOXOL-5-YL)ACETYL)-3-THIENYLSULFONAMIDO)ISOXAZOLE.” The disclosure of the above-referenced application is incorporated by reference herein in its entirety.
FIELD
[0002] Provided herein are processes for the preparation of 4-chloro-3-methyl-5-(2-(2-(6-methylbenzo[d][1,3]dioxol-5-yl)acetyl)-3-thienylsulfonamido)isoxazole, a compound useful for the treatment of endothelin-mediated disorders.
BACKGROUND
[0003] 4-chloro-3-methyl-5-(2-(2-(6-methylbenzo[d][1,3]dioxol-5-yl)acetyl)-3-thienylsulfonamido)isoxazole is an endothelin antagonist. (See U.S. Pat. Nos. 5,783,705, 5,962,490, 6,248,767) Endothelin antagonists are useful for the treatment of hypertension such as peripheral circulatory failure, heart disease such as angina pectoris, cardiomyopathy, arteriosclerosis, myocardial infarction, pulmonary hypertension, vasospasm, vascular restenosis, Raynaud's disease, cerebral stroke such as cerebral arterial spasm, cerebral ischemia, late phase cerebral spasm after subarachnoid hemorrhage, asthma, bronchoconstriction, renal failure, particularly post-ischemic renal failure, cyclosporine nephrotoxicity such as acute renal failure, colitis, as well as other inflammatory diseases, endotoxic shock caused by or associated with endothelin, and other diseases in which endothelin has been implicated. Provided herein are processes for the preparation of 4-chloro-3-methyl-5-(2-(2-(6-methylbenzo[d][1,3]dioxol-5-yl)acetyl)-3-thienylsulfonamido)isoxazole.
SUMMARY
[0004] Provided herein are processes for the preparation of 4-chloro-3-methyl-5-(2-(2-(6-methylbenzo[d][1,3]dioxol-5-yl)acetyl)-3-thienylsulfonamido)isoxazole:
or a pharmaceutically acceptable derivative thereof.
[0005] In one aspect, provided is a process for preparing the compound of Formula (I), or a pharmaceutically acceptable derivative thereof, wherein the process involves a step of reacting a compound of Formula (II):
with a compound of Formula (III):
wherein [M] is a metal, a metal halide, or a metal complex.
DETAILED DESCRIPTION
Definitions
[0006] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this invention belongs. All patents, applications, published applications and other publications are incorporated by reference in their entirety. In the event that there are a plurality of definitions for a term herein, those in this section prevail unless stated otherwise.
[0007] As used herein, pharmaceutically acceptable derivatives of a compound include salts, esters, enol ethers, enol esters, acetals, ketals, orthoesters, hemiacetals, hemiketals, solvates, hydrates or prodrugs thereof. Such derivatives may be readily prepared by those of skill in this art using known methods for such derivatization. The compounds produced may be administered to animals or humans without substantial toxic effects and either are pharmaceutically active or are prodrugs. Pharmaceutically acceptable salts include, but are not limited to, amine salts, such as but not limited to N,N′-dibenzylethylenediamine, chloroprocaine, choline, ammonia, diethanolamine and other hydroxyalkylamines, ethylenediamine, N-methylglucamine, procaine, N-benzylphenethylamine, 1-para-chlorobenzyl-2-pyrrolidin-1′-ylmethyl-benzimidazole, diethylamine and other alkylamines, piperazine and tris(hydroxymethyl)aminomethane; alkali metal salts, such as but not limited to lithium, potassium and sodium; alkali earth metal salts, such as but not limited to barium, calcium and magnesium; transition metal salts, such as but not limited to zinc; and other metal salts, such as but not limited to sodium hydrogen phosphate and disodium phosphate; and also including, but not limited to, salts of mineral acids, such as but not limited to hydrochlorides and sulfates; and salts of organic acids, such as but not limited to acetates, lactates, malates, tartrates, citrates, ascorbates, succinates, butyrates, valerates and fumarates. Pharmaceutically acceptable esters include, but are not limited to, alkyl, alkenyl, alkynyl, alk(en)(yn)yl, aryl, aralkyl, and cycloalkyl esters of acidic groups, including, but not limited to, carboxylic acids, phosphoric acids, phosphinic acids, sulfonic acids, sulfinic acids and boronic acids. Pharmaceutically acceptable enol ethers include, but are not limited to, derivatives of formula C═C(OR) where R is hydrogen, alkyl, alkenyl, alkynyl, alk(en)(yn)yl, aryl, aralkyl, or cycloalkyl. Pharmaceutically acceptable enol esters include, but are not limited to, derivatives of formula C═C(OC(O)R) where R is hydrogen, alkyl, alkenyl, alkynyl, aryl, aralkyl, or cycloalkyl. Pharmaceutically acceptable solvates and hydrates are complexes of a compound with one or more solvent or water molecules, or 1 to about 100, or 1 to about 10, or one to about 2, 3 or 4, solvent or water molecules.
[0008] It is to be understood that the compounds provided herein may contain chiral centers. Such chiral centers may be of either the (R) or (S) configuration, or may be a mixture thereof. Thus, the compounds provided herein may be enantiomerically pure, or be stereoisomeric or diastereomeric mixtures. It is to be understood that the chiral centers of the compounds provided herein may undergo epimerization in vivo. As such, one of skill in the art will recognize that administration of a compound in its (R) form is equivalent, for compounds that undergo epimerization in vivo, to administration of the compound in its (S) form.
[0009] As used herein, alkyl refers to an unbranched or branched hydrocarbon chain. An alkyl group may be unsubstituted or substituted with one or more heteroatoms.
[0010] As used herein, alkenyl refers to an unbranched or branched hydrocarbon chain comprising one or more double bonds. The double bond of an alkenyl group may be unconjugated or conjugated to another unsaturated group. An alkenyl group may be unsubstituted or substituted with one or more heteroatoms.
[0011] As used herein, alkynyl refers to an unbranched or branched hydrocarbon chain comprising one of more triple bonds therein. The triple bond of an alkynyl group may be unconjugated or conjugated to another unsaturated group. An alkynyl group may be unsubstituted or substituted with one or more heteroatoms.
[0012] As used herein, alk(en)(yn)yl refers to an unbranched or branched hydrocarbon group comprising at least one double bond and at least one triple bond. The double bond or triple bond of an alk(en)(yn)yl group may be unconjugated or conjugated to another unsaturated group. An alk(en)(yn)yl group may be unsubstituted or substituted with one or more heteroatoms.
[0013] Exemplary alkyl, alkenyl, alkynyl, and alk(en)(yn)yl groups herein include, but are not limited to, methyl, ethyl, propyl, isopropyl, isobutyl, n-butyl, sec-butyl, tert-butyl, isopentyl, neopentyl, tert-pentyl, isohexyl, allyl(propenyl) and propargyl(propynyl).
[0014] As used herein, “aryl” refers to aromatic monocyclic or multicyclic groups containing from 6 to 19 carbon atoms. Aryl groups include, but are not limited to groups such as unsubstituted or substituted fluorenyl, unsubstituted or substituted phenyl, and unsubstituted or substituted naphthyl.
[0015] As used herein, “heteroaryl” refers to a monocyclic or multicyclic aromatic ring system, in certain embodiments, of about 5 to about 15 members where one or more, in one embodiment 1 to 3, of the atoms in the ring system is a heteroatom, that is, an element other than carbon, including but not limited to, nitrogen, oxygen or sulfur. The heteroaryl group may be optionally fused to a benzene ring. Heteroaryl groups include, but are not limited to, furyl, imidazolyl, pyrimidinyl, tetrazolyl, thienyl, pyridyl, pyrrolyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl, triazolyl, quinolinyl or isoquinolinyl.
[0016] As used herein, “halo,” “halogen,” or “halide” refers to F, Cl, Br or I.
[0017] As used herein, solvent refers to any liquid that completely or partially dissolves a solid, liquid, or gaseous solute, resulting in a solution such as but not limited to hexane, benzene, toluene, diethyl ether, chloroform, ethyl acetate, dichloromethane, carbon tetrachloride, 1,4-dioxane, tetrahydrofuran, glyme, diglyme, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dimethylacetamide, or N-methyl-2-pyrrolidone.
[0018] As used herein, dehydrating agent refers to any compound that promotes the formation of carboxamides from carboxylic acids, such as but not limited to thionyl chloride, sulfuryl chloride, a carbodiimide, an anhydride or a mixed anhydride, a phenol (such as but not limited to nitrophenol, pentafluorophenol, or phenol), or a compound of Formula (A):
wherein each of X and Y is independently an unsubstituted or substituted heteroaryl group (such as but not limited to imidazolyl, benzimidazolyl, or benzotriazolyl). Examples of dehydrating agents further include, but are not limited to, benzotriazole-1-yl-oxy-tris-(dimethylamino)-phosphonium hexafluorophosphate (BOP), N,N′-carbonyldiimidazole (CDI), 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one (DEPBT), 1-ethyl-3-(3-dimethyllaminopropyl)carbodiimide (EDC), 2-(7-aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HATU), 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU), 1-hydroxybenzotriazole (HOBt), benzotriazole-1-yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate (PyBOP), 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU), O-(3,4-dihydro-4-oxo-1,2,3-benzotriazine-3-yl)-N,N,N,N-tetramethyluronium tetrafluoroborate (TDBTU), 3-(diethyloxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one (DEPBT), dicyclohexylcarbodiimide (DCC), N,N′-diisopropylcarbodiimide (DIC), or 1-hydroxy-7-azabenzotriazole (HOAt).
[0019] As used herein, metal complex refers to any metal that contains one or more ligand(s). It is to be understood that metal complexes include but are not limited to coordination complexes (including but not limited to organometallic complexes, Werner complexes, clusters, bioinorganic complexes, and combinations thereof).
[0020] It is to be understood that reactants, compounds, solvents, acids, bases, catalysts, agents, reactive groups, or the like may be added individually, simultaneously, separately, and in any order. Furthermore, it is to be understood that reactants, compounds, acids, bases, catalysts, agents, reactive groups, or the like may be pre-dissolved in solution and added as a solution (including, but not limited to, aqueous solutions). In addition, it is to be understood that reactants, compounds, solvents, acids, bases, catalysts, agents, reactive groups, or the like may be in any molar ratio.
[0021] It is to be understood that reactants, compounds, solvents, acids, bases, catalysts, agents, reactive groups, or the like may be formed in situ.
[0000] Processes
[0022] Provided herein is a process for preparing a compound of Formula (I) or a pharmaceutically acceptable derivative thereof involving the step of reacting a compound of Formula (II) with a compound of Formula (III) as depicted in Scheme A below, wherein [M] is a metal, metal halide, or metal complex.
[0023] In some embodiments, [M] contains Mg, Li, Zn, Sm, In, Sn, Ca, or Mn. In some embodiments, [M] is MgBr, MgCl, MgI, Li, ZnBr, ZnCl, or ZnI.
[0024] The compound of Formula (III), wherein [M] is a metal, a metal halide, or a metal complex may be prepared using methods known to those of ordinary skill in the art. For example, the preparation of the Grignard reagent of the compound of Formula (III), wherein [M] is MgCl, has been reported by Wu et al. (U.S. Pat. No. 6,683,103 B2).
[0025] The preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A may occur in any solvent or any combination of solvents. In some embodiments, the solvent is, or the combination of solvents contains, diethyl ether, 1,4-dioxane, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, glyme, diglyme, dimethylacetamide, or N-methyl-2-pyrrolidone. In some embodiments, the solvent is tetrahydrofuran.
[0026] In some embodiments of the preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A, [M] is MgCl and the solvent is tetrahydrofuran.
[0027] The preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A may occur at any reaction temperature. In some embodiments, the reaction temperature may vary from about −100° C. to about 100° C. In some embodiments, the reaction temperature may vary from about −50° C. to about 50° C. In some embodiments, the reaction temperature may vary from about −10° C. to about 10° C. In some embodiments, the reaction temperature may vary from about −85° C. to about −75° C. In some embodiments, the reaction temperature is about −78° C.
[0028] In some embodiments of the preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A, [M] is MgCl, the solvent is tetrahydrofuran, and the reaction temperature is about −78° C.
[0029] The preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A may occur at any reaction time. In some embodiments, the reaction time is from about 1 minute to about 24 hours. In some embodiments, the reaction time is from about 1 minute to about 8 hours. In some embodiments, the reaction time is from about 1 minute to about 3 hours. In some embodiments, the reaction time is from about 1 minute to about 1 hour. In some embodiments, the reaction time is about 5 minutes.
[0030] In some embodiments of the preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A, [M] is MgCl, the solvent is tetrahydrofuran, the reaction temperature is about −78° C., and the reaction time is about 5 minutes.
[0031] The preparation of the compound of Formula (I) as depicted in Scheme A may occur at any molar ratio according to a person of ordinary skill in the art. In some embodiments, the molar ratio of the compound of Formula (II) to the compound of Formula (III) is from about 10:1 to about 1:1. In some embodiments, the molar ratio of the compound of Formula (II) to the compound of Formula (III) is from about 5:1 to about 1:1. In some embodiments, the molar ratio of the compound of Formula (II) to the compound of Formula (III) is from about 2:1 to about 1:1. In some embodiments, the molar ratio of the compound of Formula (II) to the compound of Formula (III) is about 1.25:1. In some embodiments, the molar ratio of the compound of Formula (III) to the compound of Formula (II) is from about 10:1 to about 1:1. In some embodiments, the molar ratio of the compound of Formula (III) to the compound of Formula (II) is from about 5:1 to about 1:1. In some embodiments, the molar ratio of the compound of Formula (III) to the compound of Formula (II) is from about 3:1 to about 1:1.
[0032] In some embodiments of the preparation of the compound of Formula (I) or a pharmaceutically acceptable derivative thereof as depicted in Scheme A, [M] is MgCl, the solvent is tetrahydrofuran, the reaction temperature is about −78° C., the reaction time is about 5 minutes, and the molar ratio of the compound of Formula (II) to the compound of Formula (III) is about 1.25:1.
[0033] In another embodiment, provided is a process for preparing a compound of Formula (II) or a pharmaceutically acceptable derivative thereof by reacting a compound of Formula (IV) with a dehydrating agent or a combination of dehydrating agents as depicted in Scheme B.
[0034] In another embodiment, provided is a process for preparing a compound of Formula (II) or a pharmaceutically acceptable derivative thereof by reacting a compound of Formula (V) with a dehydrating agent or a combination of dehydrating agents as depicted in Scheme C.
[0035] The compound of Formula (IV) and the compound of Formula (V) may be prepared using methods known to those of ordinary skill in the art. For example, the preparation of the compound of Formula (IV) has been reported in Wu et al, J. Med. Chem. 1999, 42, 4485-4499. The preparation of the compound of Formula (V) may be prepared using similar methods.
[0036] The preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C may occur with any dehydrating agent or any combination of dehydrating agents according to a person of ordinary skill in the art. In some embodiments, the dehydrating agent is (or the combination of dehydrating agents are) generated in situ. In some embodiments, the dehydrating agent is (or the combination of dehydrating agents contains) thionyl chloride, sulfuryl chloride, 4-dimethylaminopyridine, a carbodiimide, an anhydride or a mixed anhydride, a phenol, or a compound of Formula (A):
wherein each of X and Y is independently an unsubstituted or substituted heteroaryl group. In some embodiments, the dehydrating agent is (or combination of dehydrating agents contains) benzotriazole-1-yl-oxy-tris-(dimethylamino)-phosphonium hexafluorophosphate (BOP), N,N′-carbonyldiimidazole (CDI), 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one (DEPBT), 1-ethyl-3-(3-dimethyllaminopropyl)carbodiimide (EDC), 2-(7-aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HATU), 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU), 1-hydroxybenzotriazole (HOBt), benzotriazole-1-yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate (PyBOP), 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU), O-(3,4-dihydro-4-oxo-1,2,3-benzotriazine-3-yl)-N,N,N,N-tetramethyluronium tetrafluoroborate (TDBTU), 3-(diethyloxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one (DEPBT), dicyclohexylcarbodiimide (DCC), N,N′-diisopropylcarbodiimide (DIC), or 1-hydroxy-7-azabenzotriazole (HOAt). In some embodiments, the dehydrating agent is dicyclohexylcarbodiimide.
[0037] The preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C may occur in any solvent or any combination of solvents. In some embodiments, the solvent is, or the combination of solvents contains, hexane, benzene, toluene, diethyl ether, chloroform, ethyl acetate, dichloromethane, carbon tetrachloride, 1,4-dioxane, tetrahydrofuran, glyme, diglyme, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dimethylacetamide, or N-methyl-2-pyrrolidone. In some embodiments, the combination of solvents contains ethyl acetate and dichloromethane.
[0038] In some embodiments of the preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C, the dehydrating agent is dicyclohexylcarbodiimide and the combination of solvents contains ethyl acetate and dichloromethane.
[0039] The preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C may occur at any reaction temperature according to a person of ordinary skill in the art. In some embodiments, the reaction temperature is from about 0° C. to about 100° C. In some embodiments, the reaction temperature is from about 20° C. to about 80° C. In some embodiments, the reaction temperature is from about 40° to about 60° C. In some embodiments, the reaction temperature is from about 20° C. to about 30° C.
[0040] In some embodiments of the preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C, the dehydrating agent is dicyclohexylcarbodiimide, the combination of solvents contains ethyl acetate and dichloromethane, and the reaction temperature is from about 20° C. to about 30° C.
[0041] The preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C may occur at any reaction time. In some embodiments, the reaction time is from about 30 minutes to about 24 hours. In some embodiments, the reaction time is from about 6 hours to about 18 hours. In some embodiments, the reaction time is about 16 hours.
[0042] In some embodiments of the preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C, the dehydrating agent is dicyclohexylcarbodiimide, the combination of solvents contains ethyl acetate and dichloromethane, the reaction temperature is from about 20° C. to about 30° C., and the reaction time is about 16 hours.
[0043] The preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C may occur at any molar ratio. In some embodiments, the molar ratio of dicyclohexylcarbodiimide to the compound of Formula (IV) is from about 10:1 to about 1:1. In some embodiments, the molar ratio of dicyclohexylcarbodiimide to the compound of Formula (IV) is from about 5:1 to about 1:1. In some embodiments, the molar ratio of dicyclohexylcarbodiimide to the compound of Formula (IV) is from about 3:1 to about 1:1. In some embodiments, the molar ratio of dicyclohexylcarbodiimide to the compound of Formula (IV) is about 1:1. In some embodiments, the molar ratio of the compound of Formula (IV) to dicyclohexylcarbodiimide is from about 5:1 to about 1:1.
[0044] In some embodiments of the preparation of the compound of Formula (II) or a pharmaceutically acceptable derivative thereof as depicted in Scheme B or Scheme C, the dehydrating agent is dicyclohexylcarbodiimide, the combination of solvents contains ethyl acetate and dichloromethane, the reaction temperature is from about 20° C. to about 30° C., the reaction time is about 16 hours, and the molar ratio of dicyclohexylcarbodiimide to the compound of Formula (IV) is about 1:1.
[0045] The following examples are provided for illustration only and are not intended to limit the scope of this disclosure.
EXAMPLE 1
Preparation of the Compound of Formula (II)
[0046] To a solution of 20.0 g of the compound of Formula (IV) in 200 ml EtOAc and 100 ml DCM was added 13.0 g DCC. After stirring for 16 hours the reaction mixture was filtered through a silica gel plug and the silica gel plug was washed with EtOAc, followed by concentration in vacuo. The crude was recrystallized form 400 ml hot EtOAC:Hexanes (1:1) go give 13.8 g of the title compound has on off white crystalline material. 1 H NMR (400 MHz, CDCl 3 ): δ 2.24 (s, 3H), 7.32 (d, J=5.1 Hz, 1H), 7.83 (d, J=5.1 Hz, 1H) ppm. MS (ESI) m/z: 304.96 [M+H] + .
EXAMPLE 2
Preparation of the Compound of Formula (I)
[0047] To a −78° C. solution of 700 mg of the compound of Formula (II) in 10 ml THF under a nitrogen atmosphere was slowly added 3.5 ml 0.53 M solution of the compound of Formula (III) ([M]=MgCl) in THF. The cooling bath was removed. After stirring for 5 minutes under a nitrogen atmosphere 10 ml 2N HCl was added, followed by extraction with 25 ml toluene. The organic layer was washed with 25 ml 2N HCl, followed by extraction with 2×25 ml sat. NaHCO 3 . The bicarbonate layers were combined and extracted with 2×25 ml EtOAc. The organic layers were combined and washed with 2N HCl/brine solution, dried over MgSO 4 and concentrated in vacuo. The crude was reconstituted in 50% water-MeCN and purified by preparative HPLC on a 30×250 mm Waters Symmetry Shield 7 μm RP 18 column with 3 injections using 35% to 75% B as gradient (A: 0.1% TFA in water; B: MeCN; diluent: 50% water in MeCN). The product containing fractions were combined and lyophilized to yield 12 mg of the title compound as a pale yellow solid in >99% purity.
[0048] Since modifications will be apparent to those of skill in the art, this disclosure is intended to be limited only by the scope of the appended claims. | Provided are processes for the preparation of 4-chloro-3-methyl-5-(2-(2-(6-methylbenzo[d][1,3]dioxol-5-yl)acetyl)-3-thienylsulfonamido)isoxazole, a compound useful for the treatment of endothelin-mediated disorders. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is continuation of U.S. Patent Application No. 11,181,450 filed on Jul. 14, 2005; which is a continuation of U.S. patent application Ser. No. 09/742,990 filed on Dec. 21, 2000, which issued on Mar. 28, 2006 as U.S. Pat. No. 7,020,111, which is a continuation-in-part to U.S. patent application Ser. No. 08/956,740 filed on Oct. 23, 1997, which issued on Apr. 10, 2001 as U.S. Pat. No. 6,215,778; which is a division of U.S. patent application Ser. No. 08/669,775 filed on Jun. 27, 1996, which issued on Aug. 25, 1998 as U.S. Pat. No. 5,799,010; which claims the benefit of U.S. Provisional Application No. 60/000,775 filed on Jun. 30, 1995.
FIELD OF INVENTION
[0002] The present invention generally pertains to Code Division Multiple Access (CDMA) communications, also known as spread-spectrum communications. More particularly, the present invention pertains to a system and method for providing a high capacity, CDMA communications system which provides for one or more simultaneous user bearer channels over a given radio frequency, allowing dynamic allocation of bearer channel rate while rejecting multipath interference.
BACKGROUND
[0003] Providing quality telecommunication services to user groups which are classified as remote, such as rural telephone systems and telephone systems in underdeveloped countries, has proven to be a challenge in recent years. These needs have been partially satisfied by wireless radio services, such as fixed or mobile frequency division multiplex (FDM) systems, frequency division multiple access (FDMA) systems, time division multiplex (TDM) systems, time division multiple access (TDMA) systems, combination frequency and time division (FD/TDMA) systems, and other land mobile radio systems. Usually, these remote services are faced with more potential users than can be supported simultaneously by their frequency or spectral bandwidth capacity.
[0004] Recognizing these limitations, recent advances in wireless communications have used spread spectrum modulation techniques to provide simultaneous communication by multiple users. Spread spectrum modulation refers to modulating an information signal with a spreading code signal; the spreading code signal being generated by a code generator where the period Tc of the spreading code is substantially less than the period of the information data bit or symbol signal. The code may modulate the carrier frequency upon which the information has been sent, called frequency-hopped spreading, or may directly modulate the signal by multiplying the spreading code with the information data signal, called direct-sequence (DS) spreading. Spread-spectrum modulation produces a signal with bandwidth substantially greater than that required to transmit the information signal. Synchronous reception and despreading of the signal at the receiver recovers the original information. A synchronous demodulator in the receiver uses a reference signal to synchronize the despreading circuits to the input spread-spectrum modulated signal to recover the carrier and information signals. The reference signal can be a spreading code which is not modulated by an information signal. Such use of synchronous spread-spectrum modulation and demodulation for wireless communication is described in U.S. Pat. No. 5,228,056 entitled “Synchronous Spread-Spectrum Communications System and Method” by Donald L. Schilling, which techniques are incorporated herein by reference.
[0005] Spread-spectrum modulation in wireless networks offers many advantages because multiple users may use the same frequency band with minimal interference to each user's receiver. Spread-spectrum modulation also reduces effects from other sources of interference. In addition, synchronous spread-spectrum modulation and demodulation techniques may be expanded by providing multiple message channels for a single user, each spread with a different spreading code, while still transmitting only a single reference signal to the user. Such use of multiple message channels modulated by a family of spreading codes synchronized to a pilot spreading code for wireless communication is described in U.S. Pat. No. 5,166,951 entitled “High Capacity Spread-Spectrum Channel” by Donald L. Schilling, which is incorporated herein by reference.
[0006] One area in which spread-spectrum techniques are used is in the field of mobile cellular communications to provide personal communication services (PCS). Such systems desirably support large numbers of users, control Doppler shift and fade, and provide high speed digital data signals with low bit error rates. These systems employ a family of orthogonal or quasi-orthogonal spreading codes, with a pilot spreading code sequence synchronized to the family of codes. Each user is assigned one of the spreading codes as a spreading function. Related problems of such a system are: supporting a large number of users with the orthogonal codes, handling reduced power available to remote units, and handling multipath fading effects. Solutions to such problems include using phased-array antennas to generate multiple steerable beams and using very long orthogonal or quasi-orthogonal code sequences. These sequences may be reused by cyclic shifting of the code synchronized to a central reference and diversity combining of multipath signals. Such problems associated with spread spectrum communications, and methods to increase the capacity of a multiple access, spread-spectrum system are described in U.S. Pat. No. 4,901,307 entitled “Spread Spectrum Multiple Access Communication System Using Satellite or Terrestrial Repeaters” by Gilhousen et al. which is incorporated herein by reference.
[0007] The problems associated with the prior art systems focus around reliable reception and synchronization of the receiver despreading circuits to the received signal. The presence of multipath fading introduces a particular problem with spread spectrum receivers in that a receiver must somehow track the multipath components to maintain code-phase lock of the receiver's despreading means with the input signal. Prior art receivers generally track only one or two of the multipath signals, but this method is not satisfactory because the combined group of low power multipath signal components may actually contain far more power than the one or two strongest multipath components. The prior art receivers track and combine the strongest components to maintain a predetermined bit error rate (BER) of the receiver. Such a receiver is described, for example, in U.S. Pat. No. 5,109,390 entitled “Diversity Receiver in a CDMA Cellular Telephone System” by Gilhousen et al. A receiver that combines all multipath components, however, is able to maintain the desired BER with a signal power that is lower than that of prior art systems because more signal power is available to the receiver. Consequently, there is a need for a spread spectrum communication system employing a receiver that tracks substantially all of the multipath signal components, so that substantially all multipath signals may be combined in the receiver, and hence the required transmit power of the signal for a given BER may be reduced.
[0008] Another problem associated with multiple access, spread-spectrum communication systems is the need to reduce the total transmitted power of users in the system, since users may have limited available power. An associated problem requiring power control in spread-spectrum systems is related to the inherent characteristic of spread-spectrum systems that one user's spread-spectrum signal is received by another user's receiver as noise with a certain power level. Consequently, users transmitting with high levels of signal power may interfere with other users' reception. Also, if a user moves relative to another user's geographic location, signal fading and distortion require that the users adjust their transmit power level to maintain a particular signal quality. At the same time, the system should keep the power that the base station receives from all users relatively constant. Finally, because it is possible for the spread-spectrum system to have more remote users than can be supported simultaneously, the power control system should also employ a capacity management method which rejects additional users when the maximum system power level is reached.
[0009] Prior spread-spectrum systems have employed a base station that measures a received signal and sends an adaptive power control (APC) signal to the remote users. Remote users include a transmitter with an automatic gain control (AGC) circuit which responds to the APC signal. In such systems the base station monitors the overall system power or the power received from each user, and sets the APC signal accordingly. Such a spread-spectrum power control system and method is described in U.S. Pat. No. 5,299,226 entitled “Adaptive Power Control for a Spread Spectrum Communications System and Method,” and U.S. Pat. No. 5,093,840 entitled “Adaptive Power Control for a Spread Spectrum Transmitter”, both by Donald L. Schilling and incorporated herein by reference. This open loop system performance may be improved by including a measurement of the signal power received by the remote user from the base station, and transmitting an APC signal back to the base station to effectuate a closed loop power control method. Such closed loop power control is described, for example, in U.S. Pat. No. 5,107,225 entitled “High Dynamic Range Closed Loop Automatic Gain Control Circuit” by Wheatley, III et al., which is incorporated herein by reference.
[0010] These power control systems, however, exhibit several disadvantages. First, the base station must perform complex power control algorithms, increasing the amount of processing in the base station. Second, the system actually experiences several types of power variation: variation in the noise power caused by the variation in the number of users and variations in the received signal power of a particular bearer channel. These variations occur with different frequency, so simple power control algorithms can be optimized to compensate for only one of the two types of variation. Finally, these power algorithms tend to drive the overall system power to a relatively high level. Consequently, there is a need for a spread-spectrum power control method that rapidly responds to changes in bearer channel power levels, while simultaneously making adjustments to all users' transmit power in response to changes in the number of users. Also, there is a need for an improved spread-spectrum communication system employing a closed loop power control system which minimizes the system's overall power requirements while maintaining a sufficient BER at the individual remote receivers. In addition, such a system should control the initial transmit power level of a remote user and manage total system capacity.
[0011] Spread-spectrum communication systems desirably should support large numbers of users, each of which has at least one communication channel. In addition, such a system should provide multiple generic information channels to broadcast information to all users and to enable users to gain access to the system. Using prior art spread-spectrum systems this could only be accomplished by generating large numbers of spreading code sequences.
[0012] Further, spread-spectrum systems should use sequences that are orthogonal or nearly orthogonal to reduce the probability that a receiver locks to the wrong spreading code sequence or phase. The use of such orthogonal codes and the benefits arising therefrom are outlined in U.S. Pat. No. 5,103,459 entitled “System and Method for Generating Signal Waveforms in a CDMA Cellular Telephone System” by Gilhousen et al., and U.S. Pat. No. 5,193,094 entitled “Method and Apparatus for Generating Super-Orthogonal Convolutional Codes and the Decoding Thereof” by Andrew J. Viterbi, both of which are incorporated herein by reference. However, generating such large families of code sequences with such properties is difficult. Also, generating large code families requires generating sequences which have a long period before repetition. Consequently, the time a receiver takes to achieve synchronization with such a long sequence is increased. Prior art spreading code generators often combine shorter sequences to make longer sequences, but such sequences may no longer be sufficiently orthogonal. Therefore, there is a need for an improved method for reliably generating large families of code sequences that exhibit nearly orthogonal characteristics and have a long period before repetition, but also include the benefit of a short code sequence that reduces the time to acquire and lock the receiver to the correct code phase. In addition, the code generation method should allow generation of codes with any period, since the spreading code period is often determined by parameters used such as data rate or frame size.
[0013] Another desirable characteristic of spreading code sequences is that the transition of the user data values occur at a transition of the code sequence values. Since data typically has a period which is divisible by 2 N , such a characteristic usually requires the code-sequence to be an even length of 2 N . However, code generators, as is well known in the art, generally use linear feedback shift registers which generate codes of length 2 N −1. Some generators include a method to augment the generated code sequence by inserting an additional code value, as described, for example, in U.S. Pat. No. 5,228,054 entitled “Power-of-Two Length Pseudo-Noise Sequence Generator with Fast Offset Adjustment” by Timothy Rueth et al., which is incorporated herein by reference. Consequently, the spread-spectrum communication system should also generate spreading code sequences of even length.
[0014] Finally, the spread-spectrum communication system should be able to handle many different types of data, such as FAX, voiceband data and ISDN, in addition to traditional voice traffic. To increase the number of users supported, many systems employ encoding techniques such as ADPCM to achieve “compression” of the digital telephone signal. FAX, ISDN and other data, however, require the channel to be a clear channel. Consequently, there is a need for a spread spectrum communication system that supports compression techniques that also dynamically modify the spread spectrum bearer channel between an encoded channel and a clear channel in response to the type of information contained in the user's signal.
SUMMARY
[0015] The present invention is embodied in a multiple access, spread spectrum communication system which processes a plurality of information signals received simultaneously over telecommunication lines for simultaneous transmission over a radio frequency (RF) channel as a code-division-multiplexed (CDM) signal. The system includes a radio carrier station (RCS) which receives a call request signal that corresponds to a telecommunication line information signal, and a user identification signal that identifies a user to which the call request and information signal are addressed. The receiving apparatus is coupled to a plurality of code division multiple access (CDMA) modems, one of which provides a global pilot code signal and a plurality of message code signals, and each of the CDMA modems combines one of the plurality of information signals with its respective message code signal to provide a spread-spectrum processed signal. The plurality of message code signals of the plurality of CDMA modems are synchronized to the global pilot code signal. The system also includes assignment apparatus that is responsive to a channel assignment signal for coupling the respective information signals received on the telecommunication lines to indicated ones of the plurality of modems. The assignment apparatus is coupled to a time-slot exchange means. The system further includes a system channel controller coupled to a remote call-processor and to the time-slot exchange means. The system channel controller is responsive to the user identification signal, to provide the channel assignment signal. In the system, an RF transmitter is connected to all of the modems to combine the plurality of spread-spectrum processed message signals with the global pilot code signal to generate a CDM signal. The RF transmitter also modulates a carrier signal with the CDM signal and transmits the modulated carrier signal through an RF communication channel.
[0016] The transmitted CDM signal is received from the RF communication channel by a subscriber unit (SU) which processes and reconstructs the transmitted information signal assigned to the subscriber. The SU includes a receiving means for receiving and demodulating the CDM signal from the carrier. In addition, the SU comprises a subscriber unit controller and a CDMA modem which includes a processing means for acquiring the global pilot code and despreading the spread-spectrum processed signal to reconstruct the transmitted information signal.
[0017] The RCS and the SUs each contain CDMA modems for transmission and reception of telecommunication signals including information signals and connection control signals. The CDMA modem comprises a modem transmitter having: a code generator for providing an associated pilot code signal and for generating a plurality of message code signals; a spreading means for combining each of the information signals with a respective one of the message code signals to generate spread-spectrum processed message signals; and a global pilot code generator which provides a global pilot code signal to which the message code signals are synchronized.
[0018] The CDMA modem also comprises a modem receiver having associated pilot code acquisition and tracking logic. The associated pilot code acquisition logic includes an associated pilot code generator; a group of associated pilot code correlators for correlating code-phase delayed versions of the associated pilot signal with a receive CDM signal for producing a despread associated pilot signal. The code phase of the associated pilot signal is changed responsive to an acquisition signal value until a detector indicates the presence of the despread associated pilot code signal by changing the acquisition signal value. The associated pilot code signal is synchronized to the global pilot signal. The associated pilot code tracking logic adjusts the associated pilot code signal in phase responsive to the acquisition signal so that the signal power level of the despread associated pilot code signal is maximized. Finally, the CDMA modem receiver includes a group of message signal acquisition circuits. Each message signal acquisition circuit includes a plurality of receive message signal correlators for correlating one of the local receive message code signals with the CDM signal to produce a respective despread receive message signal.
[0019] To generate large families of nearly mutually orthogonal codes used by the CDMA modems, the present invention includes a code sequence generator. The code sequences are assigned to a respective logical channel of the spread-spectrum communication system, which includes In-phase (I) and quadrature (Q) transmission over RF communication channels. One set of sequences is used as pilot sequences which are code sequences transmitted without modulation by a data signal. The code sequence generator circuit includes a long code sequence generator including a linear feedback shift register, a memory which provides a short, even code sequence, and a plurality of cyclic shift, feedforward sections which provide other members of the code family which exhibit minimal correlation with the code sequence applied to the feedforward circuit. The code sequence generator further includes a group of code sequence combiners for combining each phase shifted version of the long code sequence with the short, even code sequence to produce a group, or family, of nearly mutually orthogonal codes.
[0020] Further, the present invention includes several methods for efficient utilization of the spread-spectrum channels. First, the system includes a bearer channel modification system which comprises a group of message channels between a first transceiver and second transceiver. Each of the group of message channels supports a different information signal transmission rate. The first transceiver monitors a received information signal to determine the type of information signal that is received, and produces a coding signal relating to the coding signal. If a certain type of information signal is present, the first transceiver switches transmission from a first message channel to a second message channel to support the different transmission rate. The coding signal is transmitted by the first transceiver to the second transceiver, and the second transceiver switches to the second message channel to receive the information signal at a different transmission rate.
[0021] Another method to increase efficient utilization of the bearer message channels is the method of idle-code suppression used by the present invention. The spread-spectrum transceiver receives a digital data information signal including a predetermined flag pattern corresponding to an idle period. The method includes the steps of: 1) delaying and monitoring the digital data signal; 2) detecting the predetermined flag pattern; 3) suspending transmission of the digital data signal when the flag pattern is detected; and 4) transmitting the data signal as a spread-spectrum signal when the flag pattern is not detected.
[0022] The present invention includes a system and method for closed loop APC for the RCS and SUs of the spread-spectrum communication system. The SUs transmit spread-spectrum signals, the RCS acquires the spread-spectrum signals, and the RCS detects the received power level of the spread-spectrum signals plus any interfering signal including noise. The APC system includes the RCS and a plurality of SUs, wherein the RCS transmits a plurality of forward channel information signals to the SUs as a plurality of forward channel spread-spectrum signals having a respective forward transmit power level, and each SU transmits to the base station at least one reverse spread-spectrum signal having a respective reverse transmit power level and at least one reverse channel spread-spectrum signal which includes a reverse channel information signal.
[0023] The APC system includes an adaptive forward power control (AFPC) system, and an adaptive reverse power control (ARPC) system. The AFPC system operates by measuring, at the SU, a forward signal-to-noise ratio of the respective forward channel information signal, generating a respective forward channel error signal corresponding to a forward error between the respective forward signal-to-noise ratio and a pre-determined signal-to-noise value, and transmitting the respective forward channel error signal as part of a respective reverse channel information signal from the SU to the RCS. The RCS includes a plural number of AFPC receivers for receiving the reverse channel information signals and extracting the forward channel error signals from the respective reverse channel information signals. The RCS also adjusts the respective forward transmit power level of each one of the respective forward spread-spectrum signals responsive to the respective forward error signal.
[0024] The ARPC system operates by measuring, in the RCS, a reverse signal-to-noise ratio of each of the respective reverse channel information signals, generating a respective reverse channel error signal representing an error between the respective reverse channel signal-to-noise ratio and a respective pre-determined signal-to-noise value, and transmitting the respective reverse channel error signal as a part of a respective forward channel information signal to the SU. Each SU includes an ARPC receiver for receiving the forward channel information signal and extracting the respective reverse error signal from the forward channel information signal. The SU adjusts the reverse transmit power level of the respective reverse spread-spectrum signal responsive to the respective reverse error signal
BRIEF DESCRIPTION OF THE DRAWING(S)
[0025] FIG. 1 is a block diagram of a code division multiple access communication system according to the present invention.
[0026] FIG. 2 a is a block diagram of a 36 stage linear shift register suitable for use with long spreading code of the code generator of the present invention.
[0027] FIG. 2 b is a block diagram of circuitry which illustrates the feed-forward operation of the code generator.
[0028] FIG. 2 c is a block diagram of an exemplary code generator of the present invention including circuitry for generating spreading codes from the long spreading codes and the short spreading codes.
[0029] FIG. 2 d is an alternate embodiment of the code generator circuit including delay elements to compensate for electrical circuit delays.
[0030] FIG. 3 a is a graph of the constellation points of the pilot spreading code QPSK signal.
[0031] FIG. 3 b is a graph of the constellation points of the message channel QPSK signal.
[0032] FIG. 3 c is a block diagram of exemplary circuitry which implements the method of tracking the received spreading code phase of the present invention.
[0033] FIG. 4 is a block diagram of the tracking circuit that tracks the median of the received multipath signal components.
[0034] FIG. 5 a is a block diagram of the tracking circuit that tracks the centroid of the received multipath signal components.
[0035] FIG. 5 b is a block diagram of the Adaptive Vector Correlator.
[0036] FIG. 6 is a block diagram of exemplary circuitry which implements the acquisition decision method of the correct spreading code phase of the received pilot code of the present invention.
[0037] FIG. 7 is a block diagram of an exemplary pilot rake filter which includes the tracking circuit and digital phase locked loop for despreading the pilot spreading code, and generator of the weighting factors of the present invention.
[0038] FIG. 8 a is a block diagram of an exemplary adaptive vector correlator and matched filter for despreading and combining the multipath components of the present invention.
[0039] FIG. 8 b is a block diagram of an alternative implementation of the adaptive vector correlator and adaptive matched filter for despreading and combining the multipath components of the present invention.
[0040] FIG. 8 c is a block diagram of an alternative embodiment of the adaptive vector correlator and adaptive matched filter for despreading and combining the multipath components of the present invention.
[0041] FIG. 8 d is a block diagram of the Adaptive Matched Filter of one embodiment of the present invention.
[0042] FIG. 9 is a block diagram of the elements of an exemplary radio carrier station (RCS) of the present invention.
[0043] FIG. 10 is a block diagram of the elements of an exemplary multiplexer suitable for use in the RCS shown in FIG. 9 .
[0044] FIG. 11 is a block diagram of the elements of an exemplary wireless access controller (WAC) of the RCS shown in FIG. 9 .
[0045] FIG. 12 is a block diagram of the elements of an exemplary modem interface unit (MIU) of the RCS shown in FIG. 9 .
[0046] FIG. 13 is a high level block diagram showing the transmit, receive, control and code generation circuitry of the CDMA modem.
[0047] FIG. 14 is a block diagram of the transmit section of the CDMA modem.
[0048] FIG. 15 is a block diagram of an exemplary modem input signal receiver.
[0049] FIG. 16 is a block diagram of an exemplary convolutional encoder as used in the present invention.
[0050] FIG. 17 is a block diagram of the receive section of the CDMA modem.
[0051] FIG. 18 is a block diagram of an exemplary adaptive matched filter as used in the CDMA modem receive section.
[0052] FIG. 19 is a block diagram of an exemplary pilot rake as used in the CDMA modem receive section.
[0053] FIG. 20 is a block diagram of an exemplary auxiliary pilot rake as used in the CDMA modem receive section.
[0054] FIG. 21 is a block diagram of an exemplary video distribution circuit (VDC) of the RCS shown in FIG. 9 .
[0055] FIG. 22 is a block diagram of an exemplary RF transmitter/receiver and exemplary power amplifiers of the RCS shown in FIG. 9 .
[0056] FIG. 23 is a block diagram of an exemplary SU of the present invention.
[0057] FIG. 24 is a flow-chart diagram of an exemplary call establishment algorithm for an incoming call request used by the present invention for establishing a bearer channel between an RCS and an SU.
[0058] FIG. 25 is a flow-chart diagram of an exemplary call establishment algorithm for an outgoing call request used by the present invention for establishing a bearer channel between an RCS and an SU.
[0059] FIG. 26 is a flow-chart diagram of an exemplary maintenance power control algorithm of the present invention.
[0060] FIG. 27 is a flow-chart diagram of an exemplary AFPC algorithm of the present invention.
[0061] FIG. 28 is a flow-chart diagram of an exemplary ARPC algorithm of the present invention.
[0062] FIGS. 29A and 29B , taken together, are a block diagram of an exemplary closed loop power control system of the present invention when the bearer channel is established.
[0063] FIGS. 30A and 30B , taken together, are a block diagram of an exemplary closed loop power control system of the present invention during the process of establishing the bearer channel.
[0064] FIG. 31 is a schematic overview of an exemplary code division multiple access communication system in accordance with the present invention.
[0065] FIG. 32 is a diagram showing the operating range of a base station.
[0066] FIG. 33 is a timing diagram of communication signals between a base station and a subscriber unit.
[0067] FIG. 34 is a flow diagram of the establishment of a communication channel between a base station and a subscriber unit.
[0068] FIG. 35 is a graph of the transmission power output from a subscriber unit.
[0069] FIGS. 36A and 36B are flow diagrams of the establishment of a communication channel between a base station and a subscriber unit in accordance with the preferred embodiment of the present invention using short codes.
[0070] FIG. 37 is a graph of the transmission power output from a subscriber unit using short codes.
[0071] FIG. 38 shows the adaptive selection of short codes.
[0072] FIG. 39 is a block diagram of a base station in accordance with the present invention.
[0073] FIG. 40 is a block diagram of an exemplary subscriber unit in accordance with the present invention.
[0074] FIGS. 41A and 41B are flow diagrams of a ramp-up procedure implemented in accordance with the present invention.
[0075] FIG. 42 is a prior art CDMA communication system.
[0076] FIG. 43 is a graph of the distribution of acquisition opportunities of the system of FIG. 42 .
[0077] FIG. 44 is a diagram showing the propagation of signals between a base station and a plurality of subscriber units.
[0078] FIG. 45 is a flow diagram of an exemplary embodiment of the initial establishment of a communication channel between a base station and a subscriber unit using slow initial acquisition.
[0079] FIG. 46 is a flow diagram of an exemplary embodiment of the reestablishment of a communication channel between a base station and a subscriber unit using fast re-acquisition.
[0080] FIG. 47 is a diagram of the communications between a base station and a plurality of subscriber units.
[0081] FIG. 48 is a diagram of the base station and a subscriber unit which has been virtually located.
[0082] FIG. 49 is a schematic overview of a plurality of subscriber units which have been virtually located.
[0083] FIG. 50 is a subscriber unit made in accordance with one embodiment of the present invention.
[0084] FIG. 51 is a flow diagram of an alternative embodiment of the initial establishment of a communication channel between a base station and a subscriber unit using slow initial acquisition.
[0085] FIG. 52 is a flow diagram of an alternative embodiment of the reestablishment of a communication channel between a base station and a subscriber unit using fast re-acquisition.
[0086] FIG. 53 is a flow diagram of an alternative embodiment of the initial establishment of a communication channel between a base station and a subscriber unit using slow initial acquisition.
[0087] FIG. 54 is a block diagram of a prior art data communication bus.
[0088] FIG. 55 is a table of prior art data bus architectures.
[0089] FIG. 56 is a simplified block diagram of an embodiment of the present invention.
[0090] FIGS. 57A-57E , taken together, are an electrical schematic of an embodiment of the present invention.
[0091] FIG. 58 is a block diagram of the message transmit DMA.
[0092] FIG. 59 is a block diagram of the message receive DMA.
[0093] FIG. 60 is a block diagram of the digital processor system.
[0094] FIG. 61 is a general flow diagram of the transmit instruction.
[0095] FIG. 62 is a state diagram of the inquiry phase.
[0096] FIG. 63 is a state diagram of the arbitrate phase.
[0097] FIG. 64 is a state diagram of the transmit phase.
[0098] FIG. 65 is a general flow diagram of the receive instruction.
[0099] FIG. 66 is a state diagram of the delay phase.
[0100] FIG. 67 is a state diagram of the receive phase.
[0101] FIG. 68 is a block diagram of a communication system in accordance with the present invention connected to originating and terminating nodes.
[0102] FIG. 69 is a flow diagram of the establishment of a communication channel between originating and terminating nodes in accordance with the prior art.
[0103] FIG. 70 is a flow diagram of the establishment of a communication channel between originating and terminating nodes in accordance with the present invention.
[0104] FIG. 71 is a block diagram of a base station in accordance with the teachings of the present invention.
[0105] FIG. 72 is a block diagram of a prior art single input FIR filter.
[0106] FIG. 73 is a block diagram of a prior art single input FIR filter structure.
[0107] FIG. 74 is a block diagram of an alternative implementation of a prior art, single input FIR filter structure.
[0108] FIG. 75A is a block diagram of a single channel of a multichannel FIR filter.
[0109] FIG. 75B is a detailed block diagram of a multichannel FIR filter.
[0110] FIG. 76 is a block diagram showing a first refinement.
[0111] FIG. 77 is a block diagram showing a second refinement.
[0112] FIG. 78 is a block diagram of the multichannel processing element.
[0113] FIG. 79A is a global block diagram of a LUT table.
[0114] FIG. 79B is a detailed block diagram showing the multichannel LUT input of the present invention.
[0115] FIG. 80 is a detailed block diagram of an embodiment of the present invention.
[0116]
[0000]
GLOSSARY OF ACRONYMS
Acronym
Definition
AC
Assigned Channels
A/D
Analog-to-Digital
ADPCM
Adaptive Differential Pulse Code Modulation
AFPC
Adaptive Forward Power Control
AGC
Automatic Gain Control
AMF
Adaptive Matched Filter
APC
Adaptive Power Control
ARPC
Adaptive Reverse Power Control
ASPT
Assigned Pilot
AVC
Adaptive Vector Correlator
AXCH
Access Channel
B-CDMA
Broadband Code Division Multiple Access
BCM
Bearer Channel Modification
BER
Bit Error Rate
BS
Base Station
CC
Call Control
CDM
Code Division Multiplex
CDMA
Code Division Multiple Access
CLK
Clock Signal Generator
CO
Central Office
CTCH
Control Channel
CUCH
Check-Up Channel
dB
Decibels
DCC
Data Combiner Circuitry
DI
Distribution Interface
DLL
Delay Locked Loop
DM
Delta Modulator
DS
Direct Sequence
EPIC
Extended PCM Interface Controller
FBCH
Fast Broadcast Channel
FDM
Frequency Division Multiplex
FD/TDMA
Frequency & Time Division Systems
FDMA
Frequency Division Multiple Access
FEC
Forward Error Correction
FSK
Frequency Shift Keying
FSU
Fixed Subscriber Unit
GC
Global Channel
GLPT
Global Pilot
GPC
Global Pilot Code
GPSK
Gaussian Phase Shift Keying
GPS
Global Positioning System
HPPC
High Power Passive Components
HSB
High Speed Bus
I
In-Phase
IC
Interface Controller
ISDN
Integrated Services Digital Network
ISST
Initial System Signal Threshold
LAXPT
Long Access Pilot
LAPD
Link Access Protocol
LCT
Local Craft Terminal
LE
Local Exchange
LFSR
Linear Feedback Shift Register
LI
Line Interface
LMS
Least Mean Square
LOL
Loss of Lock
LPF
Low Pass Filter
LSR
Linear Shift Register
MISR
Modem Input Signal Receiver
MIU
Modem Interface Unit
MM
Mobility Management
MOI
Modem Output Interface
MPC
Maintenance Power Control
MPSK
M-ary Phase Shift Keying
MSK
Minimum Shift Keying
MSU
Mobile Subscriber Unit
NE
Network Element
OMS
Operation and Maintenance System
OS
Operations System
OQPSK
Offset Quadrature Phase Shift Keying
OW
Order Wire
PARK
Portable Access Rights Key
PBX
Private Branch Exchange
PCM
Pulse Coded Modulation
PCS
Personal Communication Services
PG
Pilot Generator
PLL
Phase Locked Loop
PLT
Pilot
PN
Pseudonoise
POTS
Plain Old Telephone Service
PSTN
Public Switched Telephone Network
Q
Quadrature
QPSK
Quadrature Phase Shift Keying
RAM
Random Access Memory
RCS
Radio Carrier Station
RDI
Receiver Data Input Circuit
RDU
Radio Distribution Unit
RF
Radio Frequency
RLL
Radio Local Loop
SAXPT
Short Access Channel Pilots
SBCH
Slow Broadcast Channel
SHF
Super High Frequency
SIR
Signal Power to Interface Noise Power Ratio
SLIC
Subscriber Line Interface Circuit
SNR
Signal-to-Noise Ratio
SPC
Service PC
SPRT
Sequential Probability Ratio Test
STCH
Status Channel
SU
Subscriber Unit
TDM
Time Division Multiplexing
TMN
Telecommunication Management Network
TRCH
Traffic Channels
TSI
Time-Slot Interchanger
TX
Transmit
TXIDAT
I-Modem Transmit Data Signal
TXQDAT
Q-Modem Transmit Data Signal
UHF
Ultra High Frequency
VCO
Voltage Controlled Oscillator
VDC
Video Distribution Circuit
VGA
Variable Gain Amplifier
VHF
Very High Frequency
WAC
Wireless Access Controller
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0117] I. General System Description
[0118] The system of the present invention provides local-loop telephone service using radio links between one or more base stations and multiple remote subscriber units. In the exemplary embodiment, a radio link is described for a base station communicating with a fixed subscriber unit (FSU), but the system is equally applicable to systems including multiple base stations with radio links to both FSUs and mobile subscriber units (MSUs). Consequently, the remote subscriber units are referred to herein as subscriber units (SUs).
[0119] Referring to FIG. 1 , base station (BS) 101 provides call connection to a local exchange (LE) 103 or any other telephone network switching interface, such as a private branch exchange (PBX) and includes a radio carrier station (RCS) 104 . One or more RCSs 104 , 105 , 110 connect to a radio distribution unit (RDU) 102 through links 131 , 132 , 137 , 138 , 139 , and RDU 102 interfaces with LE 103 by transmitting and receiving call set-up, control, and information signals through telco links 141 , 142 , 150 . SUs 116 , 119 communicate with the RCS 104 through radio links 161 , 162 , 163 , 164 , 165 . Alternatively, another embodiment of the invention includes several SUs and a “master” SU with functionality similar to the RCS 104 . Such an embodiment may or may not have connection to a local telephone network.
[0120] The radio links 161 to 165 operate within the frequency bands of the DCS 1800 standard (1.71-1.785 GHz and 1.805-1.880 GHz); the US-PCS standard (1.85-1.99 GHz); and the CEPT standard (2.0-2.7 GHz). Although these bands are used in the described embodiment, the invention is equally applicable to the entire UHF to SHF bands, including bands from 2.7 GHz to 5 GHz. The transmit and receive bandwidths are multiples of 3.5 MHz starting at 7 MHz, and multiples of 5 MHz starting at 10 MHz, respectively. The described system includes bandwidths of 7, 10, 10.5, 14 and 15 MHz. In the exemplary embodiment of the invention, the minimum guard band between the uplink and downlink is 20 MHz, and is desirably at least three times the signal bandwidth. The duplex separation is between 50 to 175 MHz, with the described invention using 50, 75, 80, 95, and 175 MHz. Other frequencies may also be used.
[0121] Although the described embodiment uses different spread-spectrum bandwidths centered around a carrier for the transmit and receive spread-spectrum channels, the present method is readily extended to systems using multiple spread-spectrum bandwidths for the transmit channels and multiple spread-spectrum bandwidths for the receive channels. Alternatively, because spread-spectrum communication systems have the inherent feature that one user's transmission appears as noise to another user's despreading receiver, an embodiment may employ the same spread-spectrum channel for both the transmit and receive path channels. In other words, uplink and downlink transmissions can occupy the same frequency band. Furthermore, the present method may be readily extended to multiple CDMA frequency bands, each conveying a respectively different set of messages, uplink, downlink or uplink and downlink.
[0122] The spread binary symbol information is transmitted over the radio links 161 to 165 using quadrature phase shift keying (QPSK) modulation with Nyquist Pulse Shaping in the present embodiment, although other modulation techniques may be used, including, but not limited to, offset QPSK (OQPSK), minimum shift keying (MSK), Gaussian phase shift keying (GPSK) and M-ary phase shift keying (MPSK).
[0123] The radio links 161 to 165 incorporate Broadband Code Division Multiple Access (B-CDMA™) as the mode of transmission in both the uplink and downlink directions. CDMA (also known as spread spectrum) communication techniques used in multiple access systems are well-known, and are described in U.S. Pat. No. 5,228,056 entitled “Synchronous Spread-Spectrum Communications System and Method” by Donald T. Schilling. The system described utilizes the direct sequence (DS) spreading technique. The CDMA modulator performs the spread-spectrum spreading code sequence generation, which can be a pseudonoise (PN) sequence; and complex DS modulation of the QPSK signals with spreading code sequences for the in-phase (I) and quadrature (Q) channels. Pilot signals are generated and transmitted with the modulated signals, and pilot signals of the present embodiment are spreading codes not modulated by data. The pilot signals are used for synchronization, carrier phase recovery and for estimating the impulse response of the radio channel. Each SU includes a single pilot generator and at least one CDMA modulator and demodulator, together known as a CDMA modem. Each RCS 104 , 105 , 110 has a single pilot generator plus sufficient CDMA modulators and demodulators for all of the logical channels in use by all SUs.
[0124] The CDMA demodulator despreads the signal with appropriate processing to combat or exploit multipath propagation effects. Parameters concerning the received power level are used to generate the APC information which, in turn, is transmitted to the other end of the communication link. The APC information is used to control transmit power of the AFPC and ARPC links. In addition, each RCS 104 , 105 and 110 can perform maintenance power control (MPC), in a manner similar to APC, to adjust the initial transmit power of each SU 111 , 112 , 115 , 117 and 118 . Demodulation is coherent where the pilot signal provides the phase reference.
[0125] The described radio links support multiple traffic channels with data rates of 8, 16, 32, 64, 128, and 144 kbs. The physical channel to which a traffic channel is connected operates with a 64 k symbol/sec rate. Other data rates may be supported, and forward error correction (FEC) coding can be employed. For the described embodiment, FEC with coding rate of ½ and constraint length 7 is used. Other rates and constraint lengths can be used consistent with the code generation techniques employed.
[0126] Diversity combining at the radio antennas of RCS 104 , 105 and 110 is not necessary because CDMA has inherent frequency diversity due to the spread bandwidth. Receivers include adaptive matched filters (AMFs) (not shown in FIG. 1 ) which combine the multipath signals. In the present embodiment, the exemplary AMFs perform maximal ratio combining.
[0127] Referring to FIG. 1 , RCS 104 interfaces to RDU 102 through links 131 , 132 , 137 , 139 , which may use, for example, 1.544 Mb/s DS1, 2.048 Mb/s E1; or HDSL formats to receive and send digital data signals. While these are typical telephone company standardized interfaces, the present invention is not limited to these digital data formats only. The exemplary RCS line interface (not shown in FIG. 1 ) translates the line coding (such as HDB3, B8ZS, AMI) and extracts or produces framing information, performs alarms and facility signaling functions, as well as channel specific loop-back and parity check functions. The interfaces for this description provide 64 kbs PCM encoded or 32 kbs ADPCM encoded telephone traffic channels or ISDN channels to the RCS for processing. Other ADPCM encoding techniques can be used consistent with the sequence generation techniques.
[0128] The system of the present invention also supports bearer rate modification between the RCS 104 and each SU 111 , 112 , 115 , 117 and 118 communicating with the RCS 104 in which a CDMA message channel supporting 64 kbs may be assigned to voiceband data or FAX when rates above 4.8 kbs are present. Such 64 kbs bearer channel is considered an unencoded channel. For ISDN, bearer rate modification may be done dynamically, based upon the D channel messages.
[0129] In FIG. 1 , each SU 111 , 112 , 115 , 117 and 118 either includes or interfaces with a telephone unit 170 , or interfaces with a local switch (PBX) 171 . The input from the telephone unit may include voice, voiceband data and signaling. The SU translates the analog signals into digital sequences, and may also include a data terminal 172 or an ISDN interface 173 . The SU can differentiate voice input, voiceband data or FAX and digital data. The SU encodes voice data with techniques such as ADPCM at 32 kbs or lower rates, and detects voiceband data or FAX with rates above 4.8 kbs to modify the traffic channel (bearer rate modification) for unencoded transmission. Also, A-law, u-law or no compounding of the signal may be performed before transmission. For digital data, data compression techniques, such as idle flag removal, may also be used to conserve capacity and minimize interference.
[0130] The transmit power levels of the radio interface between RCS 104 and SUs 111 , 112 , 115 , 117 and 118 are controlled using two different closed loop power control methods. The AFPC method determines the downlink transmit power level, and the ARPC method determines the uplink transmit power level. The logical control channel by which SU 111 and RCS 104 , for example, transfer power control information operates at least a 16 kHz update rate. Other embodiments may use a faster or slower update rate, for example 64 kHz. These algorithms ensure that the transmit power of a user maintains an acceptable bit-error rate (BER), maintains the system power at a minimum to conserve power and maintains the power level of all SUs 111 , 112 , 115 , 117 and 118 received by RCS 104 at a nearly equal level.
[0131] In addition, the system uses an optional maintenance power control method during the inactive mode of a SU. When SU 111 is inactive or powered-down to conserve power, the unit occasionally activates to adjust its initial transmit power level setting in response to a maintenance power control signal from RCS 104 . The maintenance power signal is determined by the RCS 104 by measuring the received power level of SU 111 and present system power level and, from this, calculates the necessary initial transmit power. The method shortens the channel acquisition time of SU 111 to begin a communication. The method also prevents the transmit power level of SU 111 from becoming too high and interfering with other channels during the initial transmission before the closed loop power control reduces the transmit power.
[0132] RCS 104 obtains synchronization of its clock from an interface line such as, but not limited to, E1, T1, or HDSL interfaces. RCS 104 can also generate its own internal clock signal from an oscillator which may be regulated by a global positioning system (GPS) receiver. RCS 104 generates a global pilot code, a channel with a spreading code but no data modulation, which can be acquired by remote SUs 111 through 118 . All transmission channels of the RCS are synchronized to the pilot channel, and spreading code phases of code generators (not shown) used for logical communication channels within RCS 104 are also synchronized to the pilot channel's spreading code phase. Similarly, SUs 111 through 118 which receive the global pilot code of RCS 104 synchronize the spreading and de-spreading code phases of the code generators (not shown) of the SUs to the global pilot code.
[0133] RCS 104 , SU 111 and RDU 102 may incorporate system redundancy of system elements and automatic switching between internal functional system elements upon a failure event to prevent loss or drop-out of a radio link, power supply, traffic channel or group of traffic channels.
[0134] II. Logical Communication Channels
[0135] A ‘channel’ of the prior art is usually regarded as a communications path which is part of an interface and which can be distinguished from other paths of that interface without regard to its content. However, in the case of CDMA, separate communications paths are distinguished only by their content. The term ‘logical channel’ is used to distinguish the separate data streams, which are logically equivalent to channels in the conventional sense. All logical channels and sub-channels of the present invention are mapped to a common 64 kilo-symbols per second (ksym/s) QPSK stream. Some channels are synchronized to associated pilot codes which are generated from, and perform a similar function to the system global pilot code (GPC). The system pilot signals are not, however, considered logical channels.
[0136] Several logical communication channels are used over the RF communication link between the RCS and SU. Each logical communication channel either has a fixed, pre-determined spreading code or a dynamically assigned spreading code. For both pre-determined and assigned codes, the code phase is synchronized with the pilot code. Logical communication channels are divided into two groups: the global channel (GC) group includes channels which are either transmitted from the base station RCS to all remote SUs or from any SU to the RCS of the base station regardless of the SU's identity. The channels in the GC group may contain information of a given type for all users including those channels used by SUs to gain system access. Channels in the assigned channels (AC) group are those channels dedicated to communication between the RCS and a particular SU.
[0137] The global channels (GC) group provides for: 1) broadcast control logical channels, which provide point-to-multipoint services for broadcasting messages to all SUs and paging messages to SUs; and 2) access control logical channels which provide point-to-point services on global channels for SUs to access the system and obtain assigned channels. The RCS of the present invention has multiple access control logical channels, and one broadcast control group. An SU of the present invention has at least one access control channel and at least one broadcast control logical channel.
[0138] The global logical channels controlled by the RCS are the fast broadcast channel (FBCH) which broadcasts fast changing information concerning which services and which access channels are currently available, and the slow broadcast channel (SBCH) which broadcasts slow changing system information and paging messages. The access channel (AXCH) is used by the SUs to access an RCS and gain access to assigned channels. Each AXCH is paired with a control channel (CTCH). The CTCH is used by the RCS to acknowledge and reply to access attempts by SUs. The long access pilot (LAXPT) is transmitted synchronously with AXCH to provide the RCS with a time and phase reference. An assigned channel (AC) group contains the logical channels that control a single telecommunication connection between the RCS and a SU. The functions developed when an AC group is formed include a pair of power control logical message channels for each of the uplink and downlink connections, and depending on the type of connection, one or more pairs of traffic channels. The bearer control function performs the required forward error control, bearer rate modification, and encryption functions.
[0139] Each SU 111 , 112 , 115 , 117 and 118 has at least one AC group formed when a telecommunication connection exists, and each RCS 104 , 105 and 110 has multiple AC groups formed, one for each connection in progress. An AC group of logical channels is created for a connection upon successful establishment of the connection. The AC group includes encryption, FEC coding and multiplexing on transmission, and FEC decoding, decryption and demultiplexing on reception.
[0140] Each AC group provides a set of connection oriented point-to-point services and operates in both directions between a specific RCS, for example, RCS 104 and a specific SU, for example, SU 111 . An AC group formed for a connection can control more than one bearer over the RF communication channel associated with a single connection. Multiple bearers are used to carry distributed data such as, but not limited to, ISDN. An AC group can provide for the duplication of traffic channels to facilitate switch over to 64 kbs PCM for high speed facsimile and modem services for the bearer rate modification function.
[0141] The assigned logical channels formed upon a successful call connection and included in the AC group are a dedicated signaling channel [order wire (OW)], an APC channel, and one or more traffic channels (TRCH) which are bearers of 8, 16, 32, or 64 kbs depending on the service supported. For voice traffic, moderate rate coded speech, ADPCM or PCM can be supported on the traffic channels. For ISDN service types, two 64 kbs TRCHs form the B channels and a 16 kbs TRCH forms the D channel. Alternatively, the APC subchannel may either be separately modulated on its own CDMA channel, or may be time division multiplexed with a traffic channel or OW channel.
[0142] Each SU 111 , 112 , 115 , 117 and 118 of the present invention supports up to three simultaneous traffic channels. The mapping of the three logical channels for TRCHs to the user data is shown below in Table 1:
[0000]
TABLE 1
Mapping of service types to the three available TRCH channels
Service
TRCH(0)
TRCH(1)
TRCH(2)
16 kbs POTS
TRCH/16
not used
not used
32 + 64 kbs POTS (during BCM)
TRCH/32
TRCH/64
not used
32 kbs POTS
TRCH/32
not used
not used
64 kbs POTS
not used
TRCH/64
not used
ISDN D
not used
not used
TRCH/16
ISDN B + D
TRCH/64
not used
TRCH/16
ISDN 2B + D
TRCH/64
TRCH/64
TRCH/16
Digital LL @ 64 kbs
TRCH/64
not used
not used
Digital LL @ 2 × 64 kbs
TRCH/64
TRCH/64
not used
Analog LL @ 64 kbs
TRCH/64
not used
not used
[0143] The APC data rate is sent at 64 kbs. The APC logical channel is not FEC coded to avoid delay and is transmitted at a relatively low power level to minimize capacity used for APC. Alternatively, the APC and OW may be separately modulated using complex spreading code sequences or they may be time division multiplexed.
[0144] The OW logical channel is FEC coded with a rate ½ convolutional code. This logical channel is transmitted in bursts when signaling data is present to reduce interference. After an idle period, the OW signal begins with at least 35 symbols prior to the start of the data frame. For silent maintenance call data, the OW is transmitted continuously between frames of data. Table 2 summarizes the logical channels used in the exemplary embodiment:
[0000]
TABLE 2
Logical Channels and sub-channels of the B-CDMA Air Interface
Direction
(forward
Channel
Brief
or
Bit
Max
name
Abbr.
Description
reverse)
rate
BER
Power level
Pilot
Global Channels
Fast
FBCH
Broadcasts
F
16 kbs
1e−4
Fixed
GLPT
Broadcast
fast-changing
Channel
system
information
Slow
SBCH
Broadcasts
F
16 kbs
1e−7
Fixed
GLPT
Broadcast
paging
Channel
messages to
FSUs and
slow-changing
system
information
Access
AXCH(i)
For initial
R
32 kbs
1e−7
Controlled
LAXPT(i)
Channels
access
by APC
attempts by
FSUs
Control
CTCH(i)
For granting
F
32 kbs
1e−7
Fixed
GLPT
Channels
access
Assigned Channels
16 kbs
TRCH/
General POTS
F/R
16 kbs
1e−4
Controlled
F-GLPT
POTS
16
use
by APC
R-ASPT
32 kbs
TRCH/
General
F/R
32 kbs
1e−4
Controlled by APC
F-GLPT
POTS
32
POTS use
R-ASPT
64 kbs
TRCH/
POTS use for
F/R
64 kbs
1e−4
Controlled by APC
F-GLPT
POTS
64
in-band
R-ASPT
modems/fax
D
TRCH/
ISDN D
F/R
16 kbs
1e−7
Controlled by APC
F-GLPT
channel
16
channel
R-ASPT
Order
OW
assigned
F/R
32 kbs
1e−7
Controlled by APC
F-GLPT
wire
signaling
R-ASPT
channel
channel
APC
APC
carries APC
F/R
64 kbs
2e−1
Controlled by APC
F-GLPT
channel
commands
R-ASPT
[0145] III. The Spreading Codes
[0146] The CDMA code generators used to encode the logical channels of the present invention employ linear shift registers (LSRs) with feedback logic which is a method well known in the art. The code generators of the present embodiment of the invention generate 64 synchronous unique sequences. Each RF communication channel uses a pair of these sequences for complex spreading (in-phase and quadrature) of the logical channels, so the generator gives 32 complex spreading sequences. The sequences are generated by a single seed which is initially loaded into a shift register circuit.
[0147] IV. The Generation of Spreading Code Sequences and Seed Selection
[0148] The spreading code period of the present invention is defined as an integer multiple of the symbol duration, and the beginning of the code period is also the beginning of the symbol. The relation between bandwidths and the symbol lengths chosen for the exemplary embodiment of the present invention is:
[0000]
BW (MHZ)
L (chips/symbol)
7
91
10
130
10.5
133
14
182
15
195
[0149] The spreading code length is also a multiple of 64 and of 96 for ISDN frame support. The spreading code is a sequence of symbols, called chips or chip values. The general methods of generating pseudorandom sequences using Galois Field mathematics is known to those skilled in the art. First, the length of the LFSR to generate a code sequence is chosen, and the initial value of the register is called a “seed”. Second, the constraint is imposed that no code sequence generated by a code seed may be a cyclic shift of another code sequence generated by the same code seed. Finally, no code sequence generated from one seed may be a cyclic shift of a code sequence generated by another seed. It has been determined that the spreading code length of chip values of the present invention is:
[0000] 128×233,415=29,877,120 Equation (1)
[0000] The spreading codes are generated by combining a linear sequence of period 233415 and a nonlinear sequence of period 128.
[0150] The FBCH channel of the exemplary embodiment is an exception because it is not coded with the 128 length sequence, so the FBCH channel spreading code has period 233415.
[0151] The nonlinear sequence of length 128 is implemented as a fixed sequence loaded into a shift register with a feed-back connection. The fixed sequence can be generated by an m-sequence of length 127 padded with an extra logic 0, 1, or random value as is well known in the art.
[0152] The linear sequence of length L=233415 is generated using an LFSR circuit with 36 stages. The feedback connections correspond to an irreducible polynomial h(n) of degree 36. The polynomial h(x) chosen for the exemplary embodiment of the present invention is
[0000] h ( x )= x 36 +x 35 +x 30 +x 28 +x 26 +x 25 +x 22 +x 20 +x 19 +x 17 +x 16 +x 15 +x 14 +x 12 +x 11 +x 9 +x 8 +x 4 +x 3 +x 2 +1
[0000] or, in binary notation
[0000] h ( x )=(1100001010110010110111101101100011101) Equation (2)
[0153] A group of “seed” values for a LFSR representing the polynomial h(x) of Equation (2) which generates code sequences that are nearly orthogonal with each other is determined. The first requirement of the seed values is that the seed values do not generate two code sequences which are simply cyclic shifts of each other.
[0154] The seeds are represented as elements of GF(2 36 ) which is the field of residue classes modulo h(x). This field has a primitive element δ=x 2 +x+1 or, in binary notation
[0000] δ=(000000000000000000000000000000000111) Equation (3)
[0155] Every element of GF(2 36 ) can also be written as a power of δ reduced modulo h(x). Consequently, the seeds are represented as powers of δ, the primitive element.
[0156] The solution for the order of an element does not require a search of all values; the order of an element divides the order of the field (GF(2 36 )). When δ is any element of GF(2 36 ) with
[0000] χ e ≡1 Equation (4)
[0000] for some e, then e|2 36 −1. Therefore, the order of any element in GF(2 36 ) divides 2 36 −1. Using these constraints, it has been determined that a numerical search generates a group of seed values, n, which are powers of δ, the primitive element of h(x).
[0157] The present invention includes a method to increase the number of available seeds for use in a CDMA communication system by recognizing that certain cyclic shifts of the previously determined code sequences may be used simultaneously. The round trip delay for the cell sizes and bandwidths of the present invention are less than 3000 chips. In one embodiment of the present invention, sufficiently separated cyclic shifts of a sequence can be used within the same cell without causing ambiguity for a receiver attempting to determine the code sequence. This method enlarges the set of sequences available for use. By implementing the tests previously described, a total of 3879 primary seeds were determined through numerical computation. These seeds are given mathematically as:
[0000] δ n modulo h(x) Equation (5)
[0000] where 3879 values of n, with δ=(00, . . . 00111) as in (3), is a series incrementing by 1, starting at 1 and continuing to 1101, resuming at 2204 and continuing to 3305, resuming at 4408 and continuing to 5509, and resuming at 6612 and ending at 7184.
[0158] When all primary seeds are known, all secondary seeds of the present invention are derived from the primary seeds by shifting them multiples of 4095 chips modulo h(x). Once a family of seed values is determined, these values are stored in memory and assigned to logical channels as necessary. Once assigned, the initial seed value is simply loaded into LFSR to produce the required spreading code associated with the seed value.
[0159] V. Rapid Acquisition Feature of Long and Short Codes.
[0160] Rapid acquisition of the correct code phase by a spread-spectrum receiver is improved by designing spreading codes which are faster to detect. It should be noted that spreading code, code sequence, spreading code sequence, chip code, chip sequence or chip code sequence may be used interchangeably to refer to a modulation signal used to modulate an information signal, whereby the period of the modulation signal is substantially less than the period of the information signal. For simplicity, the term spreading code will be used. The present embodiment of the invention includes a new method of generating spreading codes that have rapid acquisition properties by using one or more of the following methods. First, a long code may be constructed from two or more short codes. The new implementation uses many spreading codes, one or more of which are rapid acquisition sequences of length L that have average acquisition phase searches r=log 2L. Sequences with such properties are well known to those practiced in the art. The average number of acquisition test phases of the resulting long sequence is a multiple of r=log 2L rather than half of the number of phases of the long sequence.
[0161] Second, a method of transmitting complex valued spreading codes (in-phase (I) and quadrature (Q) sequences) in a pilot spreading code signal may be used rather than transmitting real valued sequences. Two or more separate spreading codes may be transmitted over the complex channels. If the codes have different phases, an acquisition may be done by acquisition circuits in parallel over the different spreading codes when the relative phase shift between the two or more code channels is known. For example, for two spreading codes, one can be sent on an in phase (I) channel and one on the quadrature (Q) channel. To search the spreading codes, the acquisition detection means searches the two channels, but begins the Q channel with an offset equal to one-half of the spreading code length. With code length of N, the acquisition means starts the search at N/2 on the Q channel. The average number of tests to find acquisition is N/2 for a single code search, but searching the I and phase delayed Q channel in parallel reduces the average number of tests to N/4. The codes sent on each channel could be the same code, the same code with one channel's code phase delayed or different spreading codes.
[0162] VI. Epoch and Sub-Epoch Structures
[0163] The long complex spreading codes used for the exemplary system of the present invention have a number of chips after which the code repeats. The repetition period of the spreading code is called an epoch. To map the logical channels to CDMA spreading codes, the present invention uses an epoch and sub-epoch structure. The code period for the CDMA spreading code to modulate logical channels is 29877120 chips/code period, which is the same number of chips for all bandwidths. The code period is the epoch of the present invention, and Table 3 below defines the epoch duration for the supported chip rates. In addition, two sub-epochs are defined over the spreading code epoch and are 233415 chips and 128 chips long.
[0164] The 233415 chip sub-epoch is referred to as a long sub-epoch, and is used for synchronizing events on the RF communication interface such as encryption key switching and changing from global to assigned codes. The 128 chip short epoch is defined for use as an additional timing reference. The highest symbol rate used with a single CDMA code is 64 ksym/s. There are always an integer number of chips in a symbol duration for the supported symbol rates 64, 32, 16, and 8 ksym/s.
[0000]
TABLE 3
Bandwidths, Chip Rates, and Epochs
number of
128 chip
233415 chip
Chip Rate,
chips in a
sub-epoch
sub-epoch
Epoch
Bandwidth
Complex
64 kbit/sec
duration*
duration*
duration
(MHz)
(Mchip/sec)
symbol
(ms)
(ms)
(sec)
7
5.824
91
21.978
40.078
5.130
10
8.320
130
15.385
28.055
3.591
10.5
8.512
133
15.038
27.422
3.510
14
11.648
182
10.989
20.039
2.565
15
12.480
195
10.256
18.703
2.394
*numbers in these columns are rounded to 5 digits.
[0165] VII. Mapping of the Logical Channels to Epochs and Sub-Epochs
[0166] The complex spreading codes are designed such that the beginning of the code epoch coincides with the beginning of a symbol for all of the bandwidths supported. The present invention supports bandwidths of 7, 10, 10.5, 14, and 15 MHz. Assuming nominal 20% roll-off, these bandwidths correspond to the following chip rates in Table 4.
[0000] TABLE 4 Supported Bandwidths and Chip Rates for CDMA. R c (Complex Excess BW, Factorization BW (MHz) Mchips/sec) % L: (R c /L) = 64k of L 7 5.824 20.19 91 7 × 13 10 8.320 20.19 130 2 × 5 × 13 10.5 8.512 23.36 133 7 × 19 14 11.648 20.19 182 2 × 7 × 13 15 12.480 20.19 195 3 × 5 × 13
The number of chips in an epoch is:
[0000] N= 29877120=2 7 ×3 3 ×5×7×13×19 Equation (6)
[0167] If interleaving is used, the beginning of an interleaver period coincides with the beginning of the sequence epoch. The spreading sequences generated using the method of the present invention can support interleaver periods that are multiples of 1.5 ms for various bandwidths.
[0168] Cyclic sequences of the prior art are generated using LFSR circuits. However, this method does not generate sequences of even length. One embodiment of the spreading code generator using the code seeds generated previously is shown in FIG. 2 a , FIG. 2 b , and FIG. 2 c . The present invention uses a 36 stage LFSR 201 to generate a sequence of period N′=233415=3 3 5×7×13×19, which is C o in FIG. 2 a . In FIGS. 2 a , 2 b , and 2 c , the symbol ⊕ represents a binary addition (EXCLUSIVE-OR). A spreading code generator designed as above generates the in-phase and quadrature parts of a set of complex sequences. The tap connections and initial state of the 36 stage LFSR determine the sequence generated by this circuit. The tap coefficients of the 36 stage LFSR are determined such that the resulting sequences have the period 233415. Note that the tap connections shown in FIG. 2 a correspond to the polynomial given in Equation (2). Each resulting sequence is then overlaid by binary addition with the 128 length sequence C* to obtain the epoch period 29877120.
[0169] FIG. 2 b shows a feed forward (FF) circuit 202 which is used in the code generator. The signal X[n−1] is output of the chip delay 211 , and the input of the chip delay 211 is X[n]. The code chip C[n] is formed by the logical adder 212 from the input X[n] and X[n−1]. FIG. 2 c shows the complete spreading code generator. From the LFSR 201 , output signals go through a chain of up to 63 single stage FFs 203 cascaded as shown. The output of each FF is overlaid with the short, even code sequence C* period 128=2 7 which is stored in code memory 222 and which exhibits spectral characteristics of a pseudorandom sequence to obtain the epoch N=29877120. This sequence of 128 is determined by using an m-sequence (PN sequence) of length 127=2 7 −1 and adding a bit-value, such as logic 0, to the sequence to increase the length to 128 chips. The even code sequence C* is input to the even code shift register 221 , which is a cyclic register, that continually outputs the sequence. The short sequence is then combined with the long sequence using an EXCLUSIVE-OR operation 213 , 214 , 220 .
[0170] As shown in FIG. 2 c , up to 63 spreading codes C o through C 63 are generated by tapping the output signals of FFs 203 and logically adding the short sequence C* in binary adders 213 , 214 , and 220 , for example. One skilled in the art would realize that the implementation of FF 203 will create a cumulative delay effect for the spreading codes produced at each FF stage in the chain. This delay is due to the nonzero electrical delay in the electronic components of the implementation. The timing problems associated with the delay can be mitigated by inserting additional delay elements into the FF chain in one version of the embodiment of the invention. The FF chain of FIG. 2 c with additional delay elements is shown in FIG. 2 d.
[0171] The code-generators in the exemplary embodiment of the present invention are configured to generate either global codes or assigned codes. Global codes are CDMA codes that can be received or transmitted by all users of the system. Assigned codes are CDMA codes that are allocated for a particular connection. When a set of spreading codes are generated from the same generator as described, only the seed of the 36 stage LFSR is specified to generate a family of spreading codes. Spreading codes for all of the global codes are generated using the same LFSR circuit. Therefore, once an SU has synchronized to the global pilot signal from an RCS and knows the seed for the LFSR circuit for the global channel codes, it can generate not only the pilot spreading code but also all other global codes used by the RCS.
[0172] The signal that is upconverted to RF is generated as follows. The output signals of the above shift register circuits are converted to an antipodal sequence (0 maps into +1, 1 maps into −1). The logical channels are initially converted to QPSK signals, which are mapped as constellation points as is well known in the art. The in-phase and quadrature channels of each QPSK signal form the real and imaginary parts of the complex data value. Similarly, two spreading codes are used to form complex spreading chip values. The complex data are spread by being multiplied by the complex spreading code. Similarly, the received complex data is correlated with the conjugate of the complex spreading code to recover despread data.
[0173] VIII. Short Codes
[0174] Short codes are used for the initial ramp-up process when a SU accesses an RCS. The period of the short codes is equal to the symbol duration and the start of each period is aligned with a symbol boundary. Both SU and RCS derive the real and imaginary parts of the short codes from the last eight feed-forward sections of the code generator producing the global codes for that cell.
[0175] The short codes that are in use in the exemplary embodiment of the invention are updated every 3 ms. Other update times that are consistent with the symbol rate may be used. Therefore, a change-over occurs every 3 ms starting from the epoch boundary. At a change-over, the next symbol length portion of the corresponding feed-forward output becomes the short code. When the SU needs to use a particular short code, it waits until the first 3 ms boundary of the next epoch and stores the next symbol length portion output from the corresponding FF section. This shall be used as the short code until the next change-over, which occurs 3 ms later.
[0176] The signals represented by these short codes are known as short access channel pilots (SAXPTs).
[0177] IX. Mapping of Logical Channels to Spreading Codes
[0178] The exact relationship between the spreading codes and the CDMA logical channels and pilot signals is documented in Table 5a and Table 5b. Those signal names ending in ‘-CH’ correspond to logical channels. Those signal names ending in ‘-PT’ correspond to pilot signals, which are described in detail below.
[0000]
TABLE 5a
Spreading code sequences and global CDMA codes
Logical Channel
Sequence
Quadrature
or Pilot Signal
Direction
C 0
I
FBCH
Forward (F)
C 1
Q
FBCH
F
C 2 ⊕C*
I
GLPT
F
C 3 ⊕C*
Q
GLPT
F
C 4 ⊕C*
I
SBCH
F
C 5 ⊕C*
Q
SBCH
F
C 6 ⊕C*
I
CTCH (0)
F
C 7 ⊕C*
Q
CTCH (0)
F
C 8 ⊕C*
I
APCH (1)
F
C 9 ⊕C*
Q
APCH (1)
F
C 10 ⊕C*
I
CTCH (1)
F
C 11 ⊕C*
Q
CTCH (1)
F
C 12 ⊕C*
I
APCH (1)
F
C 13 ⊕C*
Q
APCH (1)
F
C 14 ⊕C*
I
CTCH (2)
F
C 15 ⊕C*
Q
CTCH (2)
F
C 16 ⊕C*
I
APCH (2)
F
C 17 ⊕C*
Q
APCH (2)
F
C 18 ⊕C*
I
CTCH (3)
F
C 19 ⊕C*
Q
CTCH (3)
F
C 20 ⊕C*
I
APCH (3)
F
C 21 ⊕C*
Q
APCH (3)
F
C 22 ⊕C*
I
reserved
—
C 23 ⊕C*
Q
reserved
—
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
C 40 ⊕C*
I
reserved
—
C 41 ⊕C*
Q
reserved
—
C 42 ⊕C*
I
AXCH (3)
Reverse (R)
C 43 ⊕C*
Q
AXCH (3)
R
C 44 ⊕C*
I
LAXPT (3)
R
SAXPT (3) seed
C 45 ⊕C*
Q
LAXPT (3)
R
SAXPT (3) seed
C 46 ⊕C*
I
AXCH (2)
R
C 47 ⊕C*
Q
AXCH (2)
R
C 48 ⊕C*
I
LAXPT (2)
R
SAXPT (2) seed
C 49 ⊕C*
Q
LAXPT (2)
R
SAXPT (2) seed
C 50 ⊕C*
I
AXCH (1)
R
C 51 ⊕C*
Q
AXCH (1)
R
C 52 ⊕C*
I
LAXPT (1)
R
SAXPT(1) seed
C 53 ⊕C*
Q
LAXPT (1)
R
SAXPT (1) seed
C 54 ⊕C*
I
AXCH (0)
R
C 55 ⊕C*
Q
AXCH (0)
R
C 56 ⊕C*
I
LAXPT (0)
R
SAXPT (0) seed
C 57 ⊕C*
Q
LAXPT (0)
R
SAXPT (0) seed
C 58 ⊕C*
I
IDLE
—
C 59 ⊕C*
Q
IDLE
—
C 60 ⊕C*
I
AUX
R
C 61 ⊕C*
Q
AUX
R
C 62 ⊕C*
I
reserved
—
C 63 ⊕C*
Q
reserved
—
[0000]
TABLE 5b
Spreading code sequences and assigned CDMA codes.
Logical Channel
Sequence
Quadrature
or Pilot Signal
Direction
C 0 ⊕C*
I
ASPT
Reverse (R)
C 1 ⊕C*
Q
ASPT
R
C 2 ⊕C*
I
APCH
R
C 3 ⊕C*
Q
APCH
R
C 4 ⊕C*
I
OWCH
R
C 5 ⊕C*
Q
OWCH
R
C 6 ⊕C*
I
TRCH (0)
R
C 7 ⊕C*
Q
TRCH (0)
R
C 8 ⊕C*
I
TRCH (1)
R
C 9 ⊕C*
Q
TRCH (1)
R
C 10 ⊕C*
I
TRCH (2)
R
C 11 ⊕C*
Q
TRCH (2)
R
C 12 ⊕C*
I
TRCH (3)
R
C 13 ⊕C*
Q
TRCH (3)
R
C 14 ⊕C*
I
reserved
—
C 15 ⊕C*
Q
reserved
—
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
C 44 ⊕C*
I
reserved
—
C 45 ⊕C*
Q
reserved
—
C 46 ⊕C*
I
TRCH (3)
Forward (F)
C 47 ⊕C*
Q
TRCH (3)
F
C 48 ⊕C*
I
TRCH (2)
F
C 49 ⊕C*
Q
TRCH (2)
F
C 50 ⊕C*
I
TRCH (1)
F
C 51 ⊕C*
Q
TRCH (1)
F
C 52 ⊕C*
I
TRCH (0)
F
C 53 ⊕C*
Q
TRCH (0)
F
C 54 ⊕C*
I
OWCH
F
C 55 ⊕C*
Q
OWCH
F
C 56 ⊕C*
I
APCH
F
C 57 ⊕C*
Q
APCH
F
C 58 ⊕C*
I
IDLE
—
C 59 ⊕C*
Q
IDLE
—
C 60 ⊕C*
I
reserved
—
C 61 ⊕C*
Q
reserved
—
C 62 ⊕C*
I
reserved
—
C 63 ⊕C*
Q
reserved
—
[0179] For global codes, the seed values for the 36 bit shift register are chosen to avoid using the same code, or any cyclic shift of the same code, within the same geographical area to prevent ambiguity or harmful interference. No assigned code is equal to, or a cyclic shift of, a global code.
[0180] X. Pilot Signals
[0181] The pilot signals are used for synchronization, carrier phase recovery and for estimating the impulse response of the radio channel. The RCS 104 transmits a forward link pilot carrier reference as a complex pilot code sequence to provide time and phase reference for all SUs 111 , 112 , 115 , 117 and 118 in its service area. The power level of the global pilot (GLPT) signal is set to provide adequate coverage over the whole RCS service area, which area depends on the cell size. With only one pilot signal in the forward link, the reduction in system capacity due to the pilot energy is negligible.
[0182] The SUs 111 , 112 , 115 , 117 and 118 each transmit a pilot carrier reference as a quadrature modulated (complex-valued) pilot spreading code sequence to provide a time and phase reference to the RCS for the reverse link. The pilot signal transmitted by the SU of one embodiment of the invention is 6 dB lower than the power of the 32 kbs POTS traffic channel. The reverse pilot channel is subject to APC. The reverse link pilot associated with a particular connection is called the assigned pilot (ASPT). In addition, there are pilot signals associated with access channels. These are called the long access channel pilots (LAXPTs). Short access channel pilots (SAXPTs) are also associated with the access channels and used for spreading code acquisition and initial power ramp-up. All pilot signals are formed from complex codes, as defined below:
[0000]
GLPT
(
forward
)
=
{
C
2
⊕
C
*)
+
j
·
(
C
3
⊕
C
*)
}
·
{
(
1
)
+
j
·
(
0
)
}
{
Complex
Code
}
·
{
Carrier
}
[0183] The complex pilot signals are de-spread by multiplication with conjugate spreading codes: {(C 2 ⊕C*)−j·(C 3 ⊕C*)}. By contrast, traffic channels are of the form:
[0000]
TRCH
n
(
forward
/
reverse
)
=
{
(
C
k
⊕
C
*)
+
j
·
(
C
1
⊕
C
*)
}
·
{
(
±
1
)
+
j
·
(
±
1
)
}
{
Complex
Codes
}
·
{
Data
Symbol
}
[0000] which thus form a constellation set at π/4 radians with respect to the pilot signal constellations. The GLPT constellation is shown in FIG. 3 a , and the TRCH n traffic channel constellation is shown in FIG. 3 b.
[0184] XI. Logical Channel Assignment of the FBCH, SBCH, and Traffic Channels
[0185] The FBCH is a global forward link channel used to broadcast dynamic information about the availability of services and AXCHs. Messages are sent continuously over this channel, and each message lasts approximately 1 ms. The FBCH message is 16 bits long, repeated continuously, and is epoch aligned. The FBCH is formatted as defined in Table 6.
[0000]
TABLE 6
FBCH format
Bit
Definition
0
Traffic Light 0
1
Traffic Light 1
2
Traffic Light 2
3
Traffic Light 3
4-7
service indicator bits
8
Traffic Light 0
9
Traffic Light 1
10
Traffic Light 2
11
Traffic Light 3
12-15
service indicator bits
[0186] For the FBCH, bit 0 is transmitted first. As used in Table 6, a traffic light corresponds to an access channel (AXCH) and indicates whether the particular access channel is currently in use (a red) or not in use (a green). A logic ‘1’ indicates that the traffic light is green, and a logic ‘0’ indicates the traffic light is red. The values of the traffic light bits may change from octet to octet and each 16 bit message contains distinct service indicator bits which describe the types of services that are available for the AXCHs.
[0187] One embodiment of the present invention uses service indicator bits as follows to indicate the availability of services or AXCHs. The service indicator bits { 4 , 5 , 6 , 7 , 12 , 13 , 14 , 15 } taken together may be an unsigned binary number, with bit 4 as the MSB and bit 15 as the LSB. Each service type increment has an associated nominal measure of the capacity required, and the FBCH continuously broadcasts the available capacity. This is scaled to have a maximum value equivalent to the largest single service increment possible. When a SU requires a new service or an increase in the number of bearers it compares the capacity required to that indicated by the FBCH and then considers itself blocked if the capacity is not available. The FBCH and the traffic channels are aligned to the epoch.
[0188] Slow broadcast information frames contain system or other general information that is available to all SUs and paging information frames contain information about call requests for particular SUs. Slow broadcast information frames and paging information frames are multiplexed together on a single logical channel which forms the slow broadcast channel (SBCH). As previously defined, the code epoch is a sequence of 29,877,120 chips having an epoch duration which is a function of the chip rate defined in Table 7 below. In order to facilitate power saving, the channel is divided into N “Sleep” cycles, and each cycle is subdivided into M slots, which are 19 ms long, except for 10.5 MHz bandwidth which has slots of 18 ms.
[0000]
TABLE 7
SBCH Channel Format Outline
Spreading
Epoch
Cycles/
Cycle
Slot
Bandwidth
Code Rate
Length
Epoch
Length
Slots/
Length
(MHz)
(MHz)
(ms)
N
(ms)
Cycle M
(ms)
7.0
5.824
5130
5
1026
54
19
10.0
8.320
3591
3
1197
63
19
10.5
8.512
3510
3
1170
65
18
14.0
11.648
2565
3
855
45
19
15.0
12.480
2394
2
1197
63
19
[0189] Sleep cycle slot # 1 is always used for slow broadcast information. Slots # 2 to #M−1 are used for paging groups unless extended slow broadcast information is inserted. The pattern of cycles and slots in one embodiment of the present invention run continuously at 16 kbs.
[0190] Within each sleep cycle the SU powers-up the receiver and re-acquires the pilot code. It then achieves carrier lock to a sufficient precision for satisfactory demodulation and Viterbi decoding. The settling time to achieve carrier lock may be up to 3 slots in duration. For example, an SU assigned to Slot # 7 powers up the receiver at the start of slot # 4 . Having monitored its slot the SU will have either recognized its paging address and initiated an access request, or failed to recognize its paging address in which case it reverts to the sleep mode. Table 8 shows duty cycles for the different bandwidths, assuming a wake-up duration of 3 slots.
[0000]
TABLE 8
Sleep-Cycle Power Saving
Bandwidth (MHz)
Slots/Cycle
Duty Cycle
7.0
54
7.4%
10.0
63
6.3%
10.5
65
6.2%
14.0
45
8.9%
15.0
63
6.3%
[0191] XII. Spreading code Tracking and AMF Detection in Multipath Channels
[0192] Three CDMA spreading code tracking methods in multipath fading environments are described which track the code phase of a received multipath spread-spectrum signal. The first is the prior art tracking circuit which simply tracks the spreading code phase with the highest detector output signal value, the second is a tracking circuit that tracks the median value of the code phase of the group of multipath signals, and the third is the centroid tracking circuit which tracks the code-phase of an optimized, least mean squared weighted average of the multipath signal components. The following describes the algorithms by which the spreading code phase of the received CDMA signal is tracked.
[0193] A tracking circuit has operating characteristics that reveal the relationship between the time error and the control voltage that drives a voltage controlled oscillator (VCO) of a spreading code phase tracking circuit. When there is a positive timing error, the tracking circuit generates a negative control voltage to offset the timing error. When there is a negative timing error, the tracking circuit generates a positive control voltage to offset the timing error. When the tracking circuit generates a zero value, this value corresponds to the perfect time alignment called the ‘lock out’.
[0194] FIG. 3 c shows the basic tracking circuit. Received signal r(t) is applied to matched filter 301 , which correlates r(t) with a local code-sequence c(t) generated by code generator 303 . The output signal of the matched filter x(t) is sampled at the sampler 302 to produce samples x[nT] and x[nT+T/2]. The samples x[nT] and x[nT+T/2] are used by a tracking circuit 304 to determine if the phase of the spreading code c(t) of the code generator 303 is correct. The tracking circuit 304 produces an error signal e(t) as an input to the code generator 303 . The code generator 303 uses this signal e(t) as an input signal to adjust the code-phase it generates.
[0195] In a CDMA system, the signal transmitted by the reference user is written in the low-pass representation as:
[0000]
s
(
t
)
=
∑
k
=
-
∞
∞
c
k
P
Tc
(
t
-
kTc
)
Equation
(
7
)
[0000] where c k represents the spreading code coefficients, P Tc (t) represents the spreading code chip waveform and T c is the chip duration. Assuming that the reference user is not transmitting data so that only the spreading code modulates the carrier. Referring to FIG. 3 c , the received signal is:
[0000]
r
(
t
)
=
∑
i
=
1
M
a
i
s
(
t
-
τ
i
)
Equation
(
8
)
[0000] Here, a i is due to fading effect of the multipath channel on the i-th path and τ i is the random time delay associated with the same path. The receiver passes the received signal through a matched filter, which is implemented as a correlation receiver and is described below. This operation is done in two steps: first the signal is passed through a chip matched filter and sampled to recover the spreading code chip values; then this spreading code is correlated with the locally generated spreading code.
[0196] FIG. 3 c shows the chip matched filter 301 , matched to the chip waveform P Tc (t), and the sampler 302 . Ideally, the signal x(t) at the output terminal of the chip matched filter 301 is:
[0000]
x
(
t
)
=
∑
i
=
k
M
∑
k
=
-
∞
∞
a
i
c
k
g
(
t
-
τ
i
-
kT
c
)
where
:
Equation
(
9
)
g
(
t
)
=
P
Tc
(
t
)
*
h
R
(
t
)
Equation
(
10
)
[0000] M is the number of multipath components. Here, h R (t) is the impulse response of the chip matched filter 301 and ‘*’ denotes convolution. The order of the summations can be rewritten as:
[0000]
x
_
(
t
)
=
∑
k
=
-
∞
∞
c
k
f
(
t
-
kT
c
)
where
:
Equation
(
11
)
f
(
t
)
=
∑
i
=
1
M
a
i
g
(
t
-
τ
i
)
Equation
(
12
)
[0000] In the multipath channel described above, the sampler 302 samples the output signal of the chip matched filter 301 to produce x(nT) at the maximum power level points of g(t). In practice, however, the waveform g(t) is severely distorted because of the effect of the multipath signal reception, and a perfect time alignment of the signals is not available.
[0197] When the multipath distortion in the channel is negligible and a perfect estimate of the timing is available, i.e., a i =1, τ 1 =0, and a i =0, i=2, . . . , M, the received signal is r(t)=s(t). Then, with this ideal channel model, the output of the chip matched filter becomes:
[0000]
x
(
t
)
=
∑
k
=
-
∞
∞
c
k
g
(
t
-
kT
c
)
Equation
(
13
)
[0198] When there is multipath fading, however, the received spreading code waveform is distorted, and has a number of local maxima that can change from one sampling interval to another depending on the channel characteristics. For multipath fading channels with quickly changing channel characteristics, it is not practical to try to locate the maximum of the waveform ƒ(t) in every chip period interval. Instead, a time reference may be obtained from the characteristics of ƒ(t) that may not change as quickly. Three tracking methods are described based on different characteristics of ƒ(t).
[0199] XIII. Prior Art Spreading Code Tracking Method:
[0200] Prior art tracking methods include a code tracking circuit in which the receiver attempts to determine the timing of the maximum matched filter output value of the chip waveform occurs and samples the signal accordingly. However, in multipath fading channels, the receiver despread code waveform can have a number of local maxima, especially in a mobile environment. In the following, ƒ(t) represents the received signal waveform of the spreading code chip convolved with the channel impulse response. The frequency response characteristic of ƒ(t) and the maximum of this characteristic can change rather quickly making it impractical to track the maximum of ƒ(t).
[0201] Define τ to be the time estimate that the tracking circuit calculates during a particular sampling interval. Also, define the following error function as:
[0000]
ɛ
=
{
∫
f
(
t
)
t
{
t
:
τ
-
t
>
δ
}
τ
-
t
>
δ
ɛ
=
0
τ
-
t
<
δ
Equation
(
14
)
[0000] The tracking circuits of the prior art calculate a value of the input signal that minimizes the error ε. One can write:
[0000]
min
ɛ
=
1
-
max
τ
∫
τ
-
δ
τ
+
δ
f
(
t
)
t
Equation
(
15
)
[0202] Assuming ƒ(τ) has a smooth shape in the values given, the value of τ for which ƒ(τ) is maximum minimizes the error ε, so the tracking circuit tracks the maximum point of ƒ(t).
[0203] XIV. Median Weighted Value Tracking Method
[0204] The median weighted tracking method of one embodiment of the present invention, minimizes the absolute weighted error, defined as:
[0000] ε=∫ ∞ −∞ |t −τ|ƒ( t ) dt Equation (16)
[0000] This tracking method calculates the ‘median’ signal value of ƒ(τ) by collecting information from all paths, where ƒ(τ) is as in Equation (12). In a multipath fading environment, the waveform ƒ(τ) can have multiple local maxima, but only one median. To minimize ε, the derivative of Equation (16) is taken with respect to τ and the result is equated to zero, which provides:
[0000] ∫ τ −∞ ƒ( t ) dt=∫ ∞ τ ƒ( t ) dt Equation (17)
[0000] The value of τ that satisfies Equation (17) is called the ‘median’ of ƒ(t). Therefore, the median tracking method of the present embodiment tracks the median of ƒ(t).
[0205] FIG. 4 shows an implementation of the tracking circuit based on minimizing the absolute weighted error defined above. The signal x(t) and its one-half chip offset version x(t+T/2) are sampled by the A/D converter 401 at a rate 1/T. The following Equation determines the operating characteristic of the circuit in FIG. 4 :
[0000]
ɛτ
=
∑
n
=
1
2
L
f
(
τ
-
nT
/
2
)
-
f
(
τ
+
nT
/
2
)
Equation
(
18
)
[0206] Tracking the median of a group of multipath signals keeps the received energy of the multipath signal components substantially equal on the early and late sides of the median point of the correct locally generated spreading code phase c n . The tracking circuit consists of an A/D converter 401 which samples an input signal x(t) to form the half-chip offset samples. The half chip offset samples are grouped into an early set of samples and a late set of samples. The first correlation bank adaptive matched filter 402 multiplies each early sample by the spreading code phases c(n+1), c(n+2), . . . , c(n+L), where L is small compared to the code length and approximately equal to half the number of chips of delay between the earliest and latest multipath signal. The output of each correlator is applied to a respective first sum-and-dump bank 404 . The magnitudes of the output values of the L sum-and-dumps are calculated in the calculator 406 and then summed in summer 408 to give an output value proportional to the signal energy in the early multipath signals. Similarly, a second correlation bank adaptive matched filter 403 operates on the late samples, using code phases c(n−1), c(n−2), . . . , c(n−L), and each output signal is applied to a respective sum-and-dump circuit in an integrator 405 . The magnitudes of the L sum-and-dump output signals are calculated in calculator 407 and then summed in summer 409 to give a value for the late multipath signal energy. Finally, the subtractor 410 calculates the difference and produces error signal ε(t) of the early and late signal energy values.
[0207] The tracking circuit adjusts by means of error signal ε(t) the locally generated code phases c(t) to cause the difference between the early and late values to tend toward 0.
[0208] XV. Centroid Tracking Method
[0209] The optimal spreading code tracking circuit of one embodiment of the present invention is called the squared weighted tracking (or centroid) circuit. Defining t to denote the time estimate that the tracking circuit calculates, based on some characteristic of ƒ(t), the centroid tracking circuit minimizes the squared weighted error defined as:
[0000] ε=∫ ∞ −∞ |t−τ| 2 ƒ( t ) dt Equation (19)
[0000] This function inside the integral has a quadratic form, which has a unique minimum. The value of t that minimizes ε can be found by taking the derivative of the above Equation (19) with respect to t and equating to zero, which gives:
[0000] ∫ ∞ −∞ (−2 t +2τ)ƒ( t ) dt =0 Equation (20)
[0000] Therefore, the value of t that satisfies Equation (21) is:
[0000]
τ
-
1
β
∫
-
∞
∞
tf
(
t
)
t
=
0
Equation
(
21
)
[0000] is the timing estimate that the tracking circuit calculates, where β is a constant value.
[0210] Based on these observations, a realization of an exemplary tracking circuit which minimizes the squared weighted error is shown in FIG. 5 a . The following Equation (22) determines the error signal ε(τ) of the centroid tracking circuit:
[0000]
ɛ
(
τ
)
=
∑
n
=
1
2
L
n
[
f
(
τ
-
nT
/
2
-
f
(
τ
+
nT
/
2
]
=
0
Equation
(
22
)
[0000] The value that satisfies ε(τ)=0 is the perfect estimate of the timing.
[0211] The early and late multipath signal energy on each side of the centroid point are equal. The centroid tracking circuit shown in FIG. 5 a consists of an A/D converter 501 which samples an input signal x(t) to form the half-chip offset samples. The half chip offset samples are grouped as an early set of samples and a late set of samples. The first correlation bank adaptive matched filter 502 multiplies each early sample and each late sample by the positive spreading code phases c(n+1), c(n+2), . . . , c(n+L), where L is small compared to the code length and approximately equal to half the number of chips of delay between the earliest and latest multipath signal. The output signal of each correlator is applied to a respective one of L sum-and-dump circuits of the first sum and dump bank 504 . The magnitude value of each sum-and-dump circuit of the sum and dump bank 504 is calculated by the respective calculator in the calculator bank 506 and applied to a corresponding weighting amplifier of the first weighting bank 508 . The output signal of each weighting amplifier represents the weighted signal energy in a multipath component signal.
[0212] The weighted early multipath signal energy values are summed in sample adder 510 to give an output value proportional to the signal energy in the group of multipath signals corresponding to positive code phases which are the early multipath signals. Similarly, a second correlation bank adaptive matched filter 503 operates on the late samples, using the negative spreading code phases c(n−1), c(n−2), . . . , c(n−L); each output signal is provided to a respective sum-and-dump circuit of discrete integrator 505 . The magnitude value of the L sum-and-dump output signals are calculated by the respective calculator of calculator bank 507 and then weighted in weighting bank 509 . The weighted late multipath signal energy values are summed in sample adder 511 to give an energy value for the group of multipath signals corresponding to the negative code phases which are the late multipath signals. Finally, the adder 512 calculates the difference of the early and late signal energy values to produce error sample value ε(τ).
[0213] The tracking circuit of FIG. 5 a produces error signal ε(τ) which is used to adjust the locally generated code phase c(nT) to keep the weighted average energy in the early and late multipath signal groups equal. The embodiment shown uses weighting values that increase as the distance from the centroid increases. The signal energy in the earliest and latest multipath signals is probably less than the multipath signal values near the centroid. Consequently, the difference calculated by the adder 510 is more sensitive to variations in delay of the earliest and latest multipath signals.
[0214] XVI. Quadratic Detector for Tracking
[0215] In this embodiment of the tracking method, the tracking circuit adjusts the sampling phase to be “optimal” and robust to multipath. Let f(t) represent the received signal waveform as in Equation (12) above. The particular method of optimizing starts with a delay locked loop with an error signal ε(τ) that drives the loop. The function ε(τ) must have only one zero at τ=τ 0 where τ 0 is optimal. The optimal form for ε(τ) has the canonical form:
[0000]
ɛ
(
τ
)
=
∫
-
∞
∞
w
(
t
,
τ
)
f
(
t
)
2
t
Equation
(
23
)
[0000] where w(t,τ) is a weighting function relating f(t) to the error ε(τ), and the relationship indicated by Equation (24) also holds:
[0000]
ɛ
(
τ
+
τ
0
)
=
∫
-
∞
∞
w
(
t
,
τ
+
τ
0
)
f
(
t
)
2
t
Equation
(
24
)
[0216] It follows from Equation (24) that w(t,τ) is equivalent to w(t−τ). Considering the slope M of the error signal in the neighborhood of a lock point τ 0 :
[0000]
M
=
ɛ
(
τ
)
τ
τ0
=
-
∫
-
∞
∞
w
′
(
t
-
τ
0
)
g
(
t
)
t
Equation
(
25
)
[0000] where w′(t, τ) is the derivative of w(t, τ) with respect to τ, and g(t) is the average of |f(t)| 2 .
[0217] The error ε(τ) has a deterministic part and a noise part. Let z denote the noise component in ε(τ), then |z| 2 is the average noise power in the error function ε(τ). Consequently, the optimal tracking circuit maximizes the ratio
[0000]
F
=
M
2
z
2
Equation
(
26
)
[0218] The implementation of the quadratic detector is now described. The discrete error value ε of an error signal ε(τ) is generated by performing the operation
[0000] ε=y T By Equation (27)
[0000] where the vector y represents the received signal components yi, i=0, 1, . . . L−1, as shown in FIG. 5 b . The matrix B is an L by L matrix and the elements are determined by calculating values such that the ratio F of Equation (26) is maximized. The quadratic detector described above may be used to implement the centroid tracking system described above with reference to FIG. 5 a . For this implementation, the vector y is the output signal of the sum and dump circuits 504 : y={f(τ−LT), f(τ−LT+T/2), f(τ−(L−1)T), . . . f(τ), f(τ+T/2), f(τ+T), . . . f(τ+LT)} and the matrix B is set forth in Table 9.
[0000]
TABLE 9
B matrix for quadratic form of Centroid Tracking System
L
0
0
0
0
0
0
0
0
0
0
0
L − ½
0
0
0
0
0
0
0
0
0
0
0
L − 1
0
0
0
0
0
0
0
0
0
0
0
0
½
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
−½
0
0
0
0
0
0
0
0
0
0
0
0
−L + 1
0
0
0
0
0
0
0
0
0
0
0
−L + ½
0
0
0
0
0
0
0
0
0
0
0
−L
[0219] XVII. Determining the Minimum Value of L Needed:
[0220] The value of L in the previous section determines the minimum number of correlators and sum-and-dump elements. L is chosen as small as possible without compromising the functionality of the tracking circuit.
[0221] The multipath characteristic of the channel is such that the received chip waveform ƒ(t) is spread over QT c seconds, or the multipath components occupy a time period of Q chips duration. The value of L chosen is L=Q. Q is found by measuring the particular RF channel transmission characteristics to determine the earliest and latest multipath component signal propagation delay. QT c is the difference between the earliest and latest multipath component arrival time at a receiver.
[0222] XVIII. Adaptive Vector Correlator
[0223] An embodiment of the present invention uses an adaptive vector correlator (AVC) to estimate the channel impulse response and to obtain a reference value for coherent combining of received multipath signal components. The described embodiment employs an array of correlators to estimate the complex channel response affecting each multipath component. The receiver compensates for the channel response and coherently combines the received multipath signal components. This approach is referred to as maximal ratio combining.
[0224] Referring to FIG. 6 , the input signal x(t) to the system includes interference noise of other message channels, multipath signals of the message channels, thermal noise, and multipath signals of the pilot signal. The signal is provided to AVC 601 which, in the exemplary embodiment, includes a despreading means 602 , channel estimation means for estimating the channel response 604 , correction means for correcting a signal for effects of the channel response 603 and adder 605 . The AVC despreading means 602 is composed of multiple code correlators, with each correlator using a different phase of the pilot code c(t) provided by the pilot code generator 608 . The output signal of this despreading means corresponds to a noise power level if the local pilot code of the despreading means is not in phase with the input code signal. Alternatively, it corresponds to a received pilot signal power level plus noise power level if the phases of the input pilot code and locally generated pilot code are the same. The output signals of the correlators of the despreading means are corrected for the channel response by the correction means 603 and are applied to the adder 605 which collects all multipath pilot signal power. The channel response estimation means 604 receives the combined pilot signal and the output signals of the despreading means 602 , and provides a channel response estimate signal, w(t), to the correction means 603 of the AVC, and the estimate signal w(t) is also available to the adaptive matched filter (AMF) described below. The output signal of the despreading means 602 is also provided to the acquisition decision means 606 which decides, based on a particular algorithm such as a sequential probability ratio test (SPRT), if the present output levels of the despreading circuits correspond to synchronization of the locally generated spreading code to the desired input code phase. If the detector finds no synchronization, then the acquisition decision means sends a control signal a(t) to the local pilot code generator 608 to offset its phase by one or more chip period. When synchronization is found, the acquisition decision means informs tracking circuit 607 , which achieves and maintains a close synchronization between the received and locally generated spreading codes.
[0225] An exemplary implementation of the pilot AVC used to despread the pilot spreading code is shown in FIG. 7 . The described embodiment assumes that the input signal x(τ) has been sampled with sampling period T to form samples x(nT+τ), and is composed of interference noise of other message channels, multipath signals of message channels, thermal noise and multipath signals of the pilot code. The signal x(nT+τ) is applied to L correlators, where L is the number of code phases over which the uncertainty within the multipath signals exists. Each correlator 701 , 702 , 703 comprises a multiplier 704 , 705 , 706 , which multiples the input signal with a particular phase of the pilot spreading code signal c((n+i)T) and sum-and-dump circuits 708 , 709 , 710 . The output signal of each multiplier 704 , 705 , 706 is applied to a respective sum-and dump circuit 708 , 709 , 710 to perform discrete integration. Before summing the signal energy contained in the outputs of the correlators, the AVC compensates for the channel response and the carrier phase rotation of the different multipath signals. Each output of each sum-and-dump 708 , 709 , 710 is multiplied with a derotation phasor [complex conjugate of ep(nT)] from digital phase lock loop (DPLL) 721 by the respective multiplier 714 , 715 , 716 to account for the phase and frequency offset of the carrier signal. The pilot rake AMF calculates the weighting factors wk, k=1, . . . , L, for each multipath signal by passing the output of each multiplier 714 , 715 , 716 through a low pass filter (LPF) 711 , 712 , 713 . Each despread multipath signal is multiplied by its corresponding weighting factor in a respective multiplier 717 , 718 , 719 . The output signals of the multipliers 717 , 718 , 719 are summed in a master adder 720 , and the output signal p(nT) of the accumulator 720 consists of the combined despread multipath pilot signals in noise. The output signal p(nT) is also input to the DPLL 721 to produce the error signal ep(nT) for tracking of the carrier phase.
[0226] FIGS. 8 a and 8 b show alternate embodiments of the AVC which can be used for detection and multipath signal component combining. The message signal AVCs of FIGS. 8 a and 8 b use the weighting factors produced by the pilot AVC to correct the message data multipath signals. The spreading code signal, c(nT) is the spreading code spreading sequence used by a particular message channel and is synchronous with the pilot spreading code signal. The value L is the number of correlators in the AVC circuit.
[0227] The circuit of FIG. 8 a calculates the decision variable Z which is given by:
[0000]
Z
=
w
1
∑
i
=
1
N
x
(
T
+
τ
)
c
(
T
)
+
w
2
∑
i
=
1
N
x
(
T
+
τ
)
c
(
(
+
1
)
T
)
+
…
+
w
L
∑
i
=
1
L
x
(
T
+
τ
)
c
(
(
+
L
)
T
)
Equation
(
28
)
[0000] where N is the number of chips in the correlation window. Equivalently, the decision statistic is given by:
[0000]
Z
=
x
(
T
+
τ
)
∑
i
=
1
L
w
1
c
(
i
T
)
+
x
(
2
T
+
τ
)
∑
i
=
1
L
w
1
c
(
(
i
+
1
)
T
+
…
+
x
(
NT
+
τ
)
∑
i
=
1
L
w
N
c
(
(
i
+
N
)
T
)
=
∑
k
=
1
N
x
(
kT
-
τ
)
∑
i
=
1
L
w
k
c
(
(
i
+
k
-
1
)
T
)
Equation
(
29
)
[0000] The alternative implementation that results from Equation (29) is shown in FIG. 8 b.
[0228] Referring to FIG. 8 a , the input signal x(t) is sampled to form x(nT+τ), and is composed of interference noise of other message channels, multipath signals of message channels, thermal noise, and multipath signals of the pilot code. The signal x(nT+τ) is applied to L correlators, where L is the number of code phases over which the uncertainty within the multipath signals exists. Each correlator 801 , 802 , 803 comprises a multiplier 804 , 805 , 806 , which multiples the input signal by a particular phase of the message channel spreading code signal, and a respective sum-and-dump circuit 808 , 809 , 810 . The output signal of each multiplier 804 , 805 , 806 is applied to a respective sum-and dump circuit 808 , 809 , 810 which performs discrete integration. Before summing the signal energy contained in the output signals of the correlators, the AVC compensates for the different multipath signals. Each despread multipath signal and its corresponding weighting factor, which is obtained from the corresponding multipath weighting factor of the pilot AVC, are multiplied in a respective multiplier 817 , 818 , 819 . The output signals of multipliers 817 , 818 , 819 are summed in a master adder 820 , and the output signal z(nT) of the accumulator 820 consists of sampled levels of a despread message signal in noise.
[0229] The alternative embodiment of the invention includes a new implementation of the AVC despreading circuit for the message channels which performs the sum-and-dump for each multipath signal component simultaneously. The advantage of this circuit is that only one sum-and dump circuit and one adder is necessary. Referring to FIG. 8 b , the message code sequence generator 830 provides a message code sequence to shift register 831 of length L. The output signal of each register 832 , 833 , 834 , 835 of the shift register 831 corresponds to the message code sequence shifted in phase by one chip. The output value of each register 832 , 833 , 834 , 835 is multiplied in multipliers 836 , 837 , 838 , 839 with the corresponding weighting factor w k , k=1, . . . , L obtained from the pilot AVC. The output signals of the L multipliers 836 , 837 , 838 , 839 are summed by the adding circuit 840 . The adding circuit output signal and the receiver input signal x(nT+τ) are then multiplied in the multiplier 841 and integrated by the sum-and-dump circuit 842 to produce message signal z(nT).
[0230] A third embodiment of the adaptive vector correlator is shown in FIG. 8 c . The embodiment shown uses the least mean square (LMS) statistic to implement the vector correlator and determines the derotation factors for each multipath component from the received multipath signal. The AVC of FIG. 8 c is similar to the exemplary implementation of the Pilot AVC used to despread the pilot spreading code shown in FIG. 7 . The digital phase locked loop 721 is replaced by the phase locked loop 850 having voltage controlled oscillator 851 , loop filter 852 , limiter 853 and imaginary component separator 854 . The difference between the corrected despread output signal ido and an ideal despread output signal dos is provided by adder 855 , and the difference signal is a despread error value ide which is further used by the derotation circuits to compensate for errors in the derotation factors.
[0231] In a multipath signal environment, the signal energy of a transmitted symbol is spread out over the multipath signal components. The advantage of multipath signal addition is that a substantial portion of signal energy is recovered in an output signal from the AVC. Consequently, a detection circuit has an input signal from the AVC with a higher signal-to-noise ratio (SNR), and so can detect the presence of a symbol with a lower bit-error ratio (BER). In addition, measuring the output of the AVC is a good indication of the transmit power of the transmitter, and a good measure of the system's interference noise.
[0232] XIX. Adaptive Matched Filter
[0233] One embodiment of the current invention includes an adaptive matched filter (AMF) to optimally combine the multipath signal components in a received spread spectrum message signal. The AMF is a tapped delay line which holds shifted values of the sampled message signal and combines these after correcting for the channel response. The correction for the channel response is done using the channel response estimate calculated in the AVC which operates on the pilot sequence signal. The output signal of the AMF is the combination of the multipath components which are summed to give a maximum value. This combination corrects for the distortion of multipath signal reception. The various message despreading circuits operate on this combined multipath component signal from the AMF. FIG. 8 d shows an exemplary embodiment of the AMF. The sampled signal from the A/D converter 870 is applied to the L-stage delay line 872 . Each stage of this delay line 872 holds the signal corresponding to a different multipath signal component. Correction for the channel response is applied to each delayed signal component by multiplying the component in the respective multiplier of multiplier bank 874 with the respective weighting factor w 1 , w 2 , . . . , w L from the AVC corresponding to the delayed signal component. All weighted signal components are summed in the adder 876 to give the combined multipath component signal y(t).
[0234] The combined multipath component signal y(t) does not include the correction due to phase and frequency offset of the carrier signal. The correction for the phase and frequency offset of the carrier signal is made to y(t) by multiplying y(t) with carrier phase and frequency correction (derotation phasor) in multiplier 878 . The phase and frequency correction is produced by the AVC as described previously. FIG. 8 d shows the correction as being applied before the despreading circuits 880 , but alternate embodiments of the invention can apply the correction after the despreading circuits.
[0235] XX. Method to Reduce Re-Acquisition Time with Virtual Location
[0236] One consequence of determining the difference in code phase between the locally generated pilot code sequence and a received spreading code sequence is that an approximate value for the distance between the base station and a subscriber unit can be calculated. If the SU has a relatively fixed position with respect to the RCS of the base station, the uncertainty of received spreading code phase is reduced for subsequent attempts at re-acquisition by the SU or RCS. The time required for the base station to acquire the access signal of a SU that has gone “off-hook” contributes to the delay between the SU going off-hook and the receipt of a dial tone from the PSTN. For systems that require a short delay, such as 150 msec for dial tone after off-hook is detected, a method which reduces the acquisition and bearer channel establishment time is desirable. One embodiment of the present invention uses such a method of reducing re-acquisition by use of virtual locating. Additional details of this technique are described in Section XXIII hereinafter entitled “Virtual Locating Of A Fixed SU To Reduce Re-Acquisition Time.”
[0237] The RCS acquires the SU CDMA signal by searching only those received code phases corresponding to the largest propagation delay of the particular system. In other words, the RCS assumes that all SUs are at a predetermined, fixed distance from the RCS. The first time the SU establishes a channel with the RCS, the normal search pattern is performed by the RCS to acquire the access channel. The normal method starts by searching the code phases corresponding to the longest possible delay, and gradually adjusts the search to the code phases with the shortest possible delay. However, after the initial acquisition, the SU can calculate the delay between the RCS and the SU by measuring the time difference between sending a short access signal to the RCS and receiving an acknowledgment signal, and using the received global pilot channel as a timing reference. The SU can also receive the delay value by having the RCS calculate the round trip delay difference from the code phase difference between the global pilot code generated at the RCS and the received assigned pilot code from the SU, and then sending the SU the value on a predetermined control channel. Once the round trip delay is known to the SU, the SU may adjust the code phase of the locally generated assigned pilot and spreading codes by adding the delay required to make the SU appear to the RCS to be at the predetermined fixed distance from the RCS. Although the method is explained for the largest delay, a delay corresponding to any predetermined location in the system can be used.
[0238] A second advantage of the method of reducing re-acquisition by virtual locating is that a conservation in SU power use can be achieved. Note that a SU that is “powered down” or in a sleep mode needs to start the bearer channel acquisition process with a low transmit power level and ramp-up power until the RCS can receive its signal in order to minimize interference with other users. Since the subsequent re-acquisition time is shorter, and because the SU's location is relatively fixed in relation to the RCS, the SU can ramp-up transmit power more quickly because the SU will wait a shorter period of time before increasing transmit power. The SU waits a shorter period because it knows, within a small error range, when it should receive a response from the RCS if the RCS has acquired the SU signal.
[0239] XXI. The Radio Carrier Station (RCS)
[0240] The Radio Carrier Station (RCS) of the present invention acts as a central interface between the SU and the remote processing control network element, such as a radio distribution unit (RDU). The interface to the RDU of the present embodiment follows the G.704 standard and an interface according to a modified version of DECT V5.1, but the present invention can support any interface that can exchange call control and traffic channels. The RCS receives information channels from the RDU including call control data, and traffic channel data such as, but not limited to, 32 kbs ADPCM, 64 kbs PCM and ISDN, as well as system configuration and maintenance data. The RCS also terminates the CDMA radio interface bearer channels with SUs, which channels include both control data, and traffic channel data. In response to the call control data from either the RDU or a SU, the RCS allocates traffic channels to bearer channels on the RF communication link and establishes a communication connection between the SU and the telephone network through an RDU.
[0241] As shown in FIG. 9 , the RCS receives call control and message information data into the MUXs 905 , 906 and 907 through interface lines 901 , 902 and 903 . Although E1 format is shown, other similar telecommunication formats can be supported in the same manner as described below. The MUXs shown in FIG. 9 may be implemented using circuits similar to that shown in FIG. 10 . The MUX shown in FIG. 10 includes system clock signal generator 1001 consisting of phase locked oscillators (not shown) which generate clock signals for the line PCM highway 1002 (which is part of PCM highway 910 ), and high speed bus (HSB) 970 ; and the MUX controller 1010 which synchronizes the system clock 1001 to interface line 1004 . It is contemplated that the phase lock oscillators can provide timing signals for the RCS in the absence of synchronization to a line. The MUX line interface 1011 separates the call control data from the message information data. Referring to FIG. 9 , each MUX provides a connection to the wireless access controller (WAC) 920 through the PCM highway 910 . The MUX controller 1010 also monitors the presence of different tones present in the information signal by means of tone detector 1030 . Additionally, the MUX Controller 1010 provides the ISDN D channel network signaling locally to the RDU.
[0242] The MUX line interface 1011 , such as a FALC 54 , includes an E1 interface 1012 which consists of a transmit connection pair (not shown) and a receive connection pair (not shown) of the MUX connected to the RDU or central office (CO) ISDN switch at the data rate of 2.048 Mbps. The transmit and receive connection pairs are connected to the E1 interface 1012 which translates differential tri-level transmit/receive encoded pairs into levels for use by the framer 1015 . The line interface 1011 uses internal phase-locked-loops (not shown) to produce E1-derived 2.048 MHz and 4.096 MHz clocks as well as an 8 KHz frame-sync pulse. The line interface can operate in clock-master or clock-slave mode. While the exemplary embodiment is shown as using an E1 interface, it is contemplated that other types of telephone lines which convey multiple calls may be used, for example, T1 lines or lines which interface to a private branch exchange (PBX).
[0243] The line interface framer 1015 frames the data streams by recognizing the framing patterns on channel- 1 (time-slot 0 ) of the incoming line, inserts and extracts service bits and generates/checks line service quality information.
[0244] As long as a valid E1 signal appears at the E1 interface 1012 , the FALC 54 , recovers a 2.048 MHz PCM clock signal from the E1 line. This clock, via system clock 1001 , is used system wide as a PCM highway clock signal. If the E1 line fails, the FALC 54 continues to deliver a PCM clock derived from an oscillator signal o(t) connected to the sync input (not shown) of the FALC 54 . This PCM clock serves the RCS system until another MUX with an operational E1 line assumes responsibility for generating the system clock signals.
[0245] The framer 1015 generates a received frame sync pulse, which in turn can be used to trigger the PCM Interface 1016 to transfer data onto the line PCM highway 1002 and into the RCS system for use by other elements. Since all E1 lines are frame synchronized, all line PCM highways are also frame synchronized. From this 8 kHz PCM Sync pulse, the system clock signal generator 1001 of the MUX uses a phase locked loop (not shown) to synthesize the PN×2 clock (e.g., 15.96 MHz) (W 0 (t)). The frequency of this clock signal is different for different transmission bandwidths as described in Table 7.
[0246] The MUX includes a MUX controller 1010 , such as a 25 MHz quad integrated communications controller, containing a microprocessor 1020 , program memory 1021 , and time division multiplexer (TDM) 1022 . The TDM 1022 is coupled to receive the signal provided by the framer 1015 , and extracts information placed in time slots 0 and 16 . The extracted information governs how the MUX controller 1010 processes the link access protocol-D (LAPD) data link. The call control and bearer modification messages, such as those defined as V5.1 network layer messages, are either passed to the WAC, or used locally by the MUX controller 1010 .
[0247] The RCS line PCM highway 1002 is connected to and originates with the framer 1015 through PCM Interface 1016 , and is comprised of a 2.048 MHz stream of data in both the transmit and receive direction. The RCS also contains a high speed bus (HSB) 970 which is the communication link between the MUX, WAC, and MIUs. The HSB 970 supports a data rate of, for example, 100 Mbit/sec. Each of the MUX, WAC, and MIU access the HSB using arbitration. The RCS of the present invention also can include several MUXs requiring one board to be a “master” and the rest “slaves”. Details on the implementation of the HSB may be found in Section XXXXIV hereinafter entitled “Parallel Packetized Intermodule Arbitrated High Speed Control And Data Bus.”
[0248] Referring to FIG. 9 , the wireless access controller (WAC) 920 is the RCS system controller which manages call control functions and interconnection of data streams between the MUXs 905 , 906 , 907 , modem interface units (MIUs) 931 , 932 , 933 . The WAC 920 also controls and monitors other RCS elements such as the VDC 940 , RF 950 , and power amplifiers 960 . The WAC 920 as shown in FIG. 11 , allocates bearer channels to the modems on each MIU 931 , 932 , 933 and allocates the message data on line PCM Highway 910 from the MUXs 905 , 906 , 907 to the modems on the MIUs 931 , 932 , 933 . This allocation is made through the System PCM Highway 911 by means of a time slot interchange on the WAC 920 . If more than one WAC is present for redundancy purposes, the WACs determine the master-slave relationship with a second WAC. The WAC 920 also generates messages and paging information responsive to call control signals from the MUXs 905 , 906 , 907 received from a remote processor, such as an RDU; generates broadcast data which is transmitted to the MIU master modem 934 ; and controls the generation by the MIU MM 934 of the Global system Pilot spreading code sequence. The WAC 920 also is connected to an external network manager (NM) 980 for craftsperson or user access.
[0249] Referring to FIG. 11 , the WAC includes a time-slot interchanger (TSI) 1101 which transfers information from one time slot in a line PCM highway or system PCM highway to another time slot in either the same or different line PCM highway or system PCM highway. The TSI 1101 is connected to the WAC controller 1111 of FIG. 11 which controls the assignment or transfer of information from one time slot to another time slot and stores this information in memory 1120 . The exemplary embodiment of the invention has four PCM Highways 1102 , 1103 , 1104 , 1105 connected to the TSI. The WAC also is connected to the HSB 970 , through which WAC communicates to a second WAC (not shown), to the MUXs and to the MIUs.
[0250] Referring to FIG. 11 , the WAC 920 includes a WAC controller 1111 employing, for example, a microprocessor 1112 , such as a Motorola MC 68040 and a communications processor 1113 , such as the Motorola MC68360 QUICC communications processor, and a clock oscillator 1114 which receives a clock synch signal wo(t) from the system clock generator. The clock generator is located on a MUX (not shown) to provide timing to the WAC controller 1111 . The WAC controller 1111 also includes memory 1120 including flash PROM 1121 and SRAM memory 1122 . The flash PROM 1121 contains the program code for the WAC controller 1111 and is reprogrammable for new software programs downloaded from an external source. The SRAM 1122 is provided to contain the temporary data written to and read from memory 1120 by the WAC controller 1111 .
[0251] A low speed bus 912 is connected to the WAC 920 for transferring control and status signals between the RF transmitter/receiver 950 , VDC 940 , RF 950 and power amplifier 960 as shown in FIG. 9 . The control signals are sent from the WAC 920 to enable or disable the RF transmitters/receiver 950 or power amplifier 960 , and the status signals are sent from the RF transmitters/receiver 950 or power amplifier 960 to monitor the presence of a fault condition.
[0252] The exemplary RCS contains at least one MIU 931 , which is shown in FIG. 12 and now described in detail. The MIU of the exemplary embodiment includes six CDMA modems, but the invention is not limited to this number of modems. The MIU includes a system PCM highway 1201 connected to each of the CDMA Modems 1210 , 1211 , 1212 , 1215 through a PCM Interface 1220 , a control channel bus 1221 connected to MIU controller 1230 and each of the CDMA modems 1210 , 1211 , 1212 and 1215 , an MIU clock signal generator (CLK) 1231 , and a modem output combiner 1232 . The MIU provides the RCS with the following functions: the MIU controller receives CDMA channel assignment instructions from the WAC and assigns a modem to a user information signal which is applied to the line interface of the MUX and a modem to receive the CDMA channel from the SU; it also combines the CDMA transmit modem data for each of the MIU CDMA modems; multiplexes I and Q transmit message data from the CDMA modems for transmission to the VDC; receives analog I and Q receive message data from the VDC; distributes the I and Q data to the CDMA modems; transmits and receives digital AGC data; distributes the AGC data to the CDMA modems; and sends MIU board status and maintenance information to the WAC 920 .
[0253] The MIU controller 1230 of the exemplary embodiment of the present invention contains one communication microprocessor 1240 , such as the MC68360 “QUICC” processor, and includes a memory 1242 having a Flash PROM memory 1243 and a SRAM memory 1244 . Flash PROM 1243 is provided to contain the program code for the microprocessors 1240 , and the memory 1243 is downloadable and reprogrammable to support new program versions. SRAM 1244 is provided to contain the temporary data space needed by the MC68360 microprocessor 1240 when the MIU controller 1230 reads or writes data to memory
[0254] The MIU CLK circuit 1231 provides a timing signal to the MIU controller 1230 , and also provides a timing signal to the CDMA modems. The MIU CLK circuit 1231 receives, and is synchronized to, the system clock signal wo(t). The controller clock signal generator 1213 also receives and synchronizes to the spreading code clock signal pn(t) which is distributed to the CDMA modems 1210 , 1211 , 1212 , 1215 from the MUX.
[0255] The RCS of the present embodiment includes a system modem 1210 contained on one MIU. The system modem 1210 includes a broadcast spreader (not shown) and a pilot generator (not shown). The broadcast modem provides the broadcast information used by the exemplary system, and the broadcast message data is transferred from the MIU controller 1230 to the system modem 1210 . The system modem also includes four additional modems (not shown) which are used to transmit the signals CT 1 through CT 4 and AX 1 through AX 4 . The system modem 1210 provides unweighted I and Q broadcast message data signals which are applied to the VDC. The VDC adds the broadcast message data signal to the MIU CDMA modem transmit data of all CDMA modems 1210 , 1211 , 1212 , 1215 and the global pilot signal.
[0256] The pilot generator (PG) 1250 provides the global pilot signal which is used by the present invention, and the global pilot signal is provided to the CDMA modems 1210 , 1211 , 1212 , 1215 by the MIU controller 1230 . However, other embodiments of the present invention do not require the MIU controller to generate the global pilot signal, but include a global pilot signal generated by any form of CDMA spreading code generator. In the described embodiment of the invention, the unweighted I and Q global pilot signal is also sent to the VDC where it is assigned a weight, and added to the MIU CDMA modem transmit data and broadcast message data signal.
[0257] System timing in the RCS is derived from the E1 interface. There are four MUXs in an RCS, three of which ( 905 , 906 and 907 ) are shown in FIG. 9 . Two MUXs are located on each chassis. One of the two MUXs on each chassis is designated as the master, and one of the masters is designated as the system master. The MUX which is the system master derives a 2.048 MHz PCM clock signal from the E1 interface using a phase-locked loop (not shown). In turn, the system master MUX divides the 2.048 MHz PCM clock signal in frequency by 16 to derive a 128 KHz reference clock signal. The 128 KHz reference clock signal is distributed from the MUX that is the system master to all the other MUXs. In turn, each MUX multiplies the 128 KHz reference clock signal in frequency to synthesize the system clock signal which has a frequency that is twice the frequency of the PN-clock signal. The MUX also divides the 128 KHz clock signal in frequency by 16 to generate the 8 KHz frame synch signal which is distributed to the MIUs. The system clock signal for the exemplary embodiment has a frequency of 11.648 MHz for a 7 MHz bandwidth CDMA channel Each MUX also divides the system clock signal in frequency by 2 to obtain the PN-clock signal and further divides the PN-clock signal in frequency by 29 877 120 (the PN sequence length) to generate the PN-synch signal which indicates the epoch boundaries. The PN-synch signal from the system master MUX is also distributed to all MUXs to maintain phase alignment of the internally generated clock signals for each MUX. The PN-synch signal and the frame synch signal are aligned. The two MUXs that are designated as the master MUXs for each chassis then distribute both the system clock signal and the PN-clock signal to the MIUs and the VDC.
[0258] The PCM highway interface 1220 connects the system PCM highway 911 to each CDMA modem 1210 , 1211 , 1212 , 1215 . The WAC controller transmits modem control information, including traffic message control signals for each respective user information signal to the MIU controller 1230 through the HSB 970 . Each CDMA modem 1210 , 1211 , 1212 , 1215 receives a traffic message control signal, which includes signaling information, from the MIU controller 1111 . Traffic message control signals also include call control (CC) information and spreading code and despreading code sequence information.
[0259] The MIU also includes the transmit data combiner 1232 which adds weighted CDMA modem transmit data including in-phase (I) and quadrature (Q) modem transmit data from the CDMA modems 1210 , 1211 , 1212 , 1215 on the MIU. The I modem transmit data is added separately from the Q modem transmit data. The combined I and Q modem transmit data output signal of the transmit data combiner 1232 is applied to the I and Q multiplexer 1233 that creates a single CDMA transmit message channel composed of the I and Q modem transmit data multiplexed into a digital data stream.
[0260] The receiver data input Circuit (RDI) 1234 receives the analog differential I and Q Data from the video distribution circuit (VDC) 940 shown in FIG. 9 and distributes analog differential I and Q data to each of the CDMA modems 1210 , 1211 , 1212 , 1215 of the MIU. The automatic gain control (AGC) distribution circuit 1235 receives the AGC data signal from the VDC and distributes the AGC data to each of the CDMA modems of the MIU. The TRL circuit 1233 receives the traffic lights information and similarly distributes the Traffic light data to each of the Modems 1210 , 1211 , 1212 , 1215 .
[0261] XXII. The CDMA Modem
[0262] The CDMA modem provides for generation of CDMA spreading codes and synchronization between transmitter and receiver. It also provides four full duplex channels (TR 0 , TR 1 , TR 2 , TR 3 ) programmable to 64, 32, 16, and 8 ksym/sec. each, for spreading and transmission at a specific power level. The CDMA modem measures the received signal strength to allow automatic power control, it generates and transmits pilot signals, and encodes and decodes using the signal for forward error correction (FEC). The modem in an SU also performs transmitter spreading code pulse shaping using an FIR filter. The CDMA modem is also used by the subscriber unit (SU), and in the following discussion those features which are used only by the SU are distinctly pointed out. The operating frequencies of the CDMA modem are given in Table 10.
[0000]
TABLE 10
Operating Frequencies
Bandwidth
Chip Rate
Symbol Rate
Gain
(MHz)
(MHz)
(KHz)
(Chips/Symbol)
7
5.824
64
91
10
8.320
64
130
10.5
8.512
64
133
14
11.648
64
182
15
12.480
64
195
[0263] Each CDMA modem 1210 , 1211 , 1212 , 1215 of FIG. 12 , and as shown in FIG. 13 , is composed of a transmit section 1301 and a receive section 1302 . Also included in the CDMA modem is a control center 1303 which receives control messages CNTRL from the external system. These messages are used, for example, to assign particular spreading codes, activate the spreading or despreading or to assign transmission rates. In addition, the CDMA modem has a code generator means 1304 used to generate the various spreading and despreading codes used by the CDMA modem. The transmit section 1301 is for transmitting the input information and control signals m i (t), i=1, 2, . . . I as spread-spectrum processed user information signals sc j (t), j=1, 2, . . . J. The transmit section 1301 receives the global pilot code from the code generator 1304 which is controlled by the control means 1303 . The spread spectrum processed user information signals are ultimately added to other similar processed signals and transmitted as CDMA channels over the CDMA RF forward message link, for example to the SUs. The receive section 1302 receives CDMA channels as r(t) and despreads and recovers the user information and control signals rc k (t), k=1, 2, . . . K transmitted over the CDMA RF reverse message link, for example to the RCS from the SUs.
[0264] XXIII. CDMA Modem Transmitter Section
[0265] Referring to FIG. 14 , the code generator means 1304 includes transmit timing control logic 1401 and spreading code PN-generator 1402 , and the transmit section 1301 includes modem input signal receiver (MISR) 1410 , convolution encoders 1411 , 1412 , 1413 , 1414 , spreaders 1420 , 1421 , 1422 , 1423 , 1424 and combiner 1430 . The transmit section 1301 receives the message data channels MESSAGE, convolutionally encodes each message data channel in the respective convolutional encoder 1411 , 1412 , 1413 , 1414 , modulates the data with random spreading code sequence in the respective spreader 1420 , 1421 , 1422 , 1423 , 1424 , and combines modulated data from all channels, including the pilot code received in the described embodiment from the code generator, in the combiner 1430 to generate I and Q components for RF transmission. The transmitter section 1301 of the present embodiment supports four (TR 0 , TR 1 , TR 2 , TR 3 ) 64, 32, 16, 8 kbs programmable channels. The message channel data is a time multiplexed signal received from the PCM highway 1201 through PCM interface 1220 and input to the MISR 1410 .
[0266] FIG. 15 is a block diagram of an exemplary MISR 1410 . For the exemplary embodiment of the present invention, a counter is set by the 8 KHz frame synchronization signal MPCMSYNC and is incremented by 2.048 MHz MPCMCLK from the timing circuit 1401 . The counter output is compared by comparator 1502 against TRCFG values corresponding to slot time location for TR 0 , TR 1 , TR 2 , TR 3 message channel data; and the TRCFG values are received from the MIU controller 1230 in MCTRL. The comparator sends count signal to the registers 1505 , 1506 , 1507 and 1508 which clocks message channel data into buffers 1510 , 1511 , 1512 , 1513 using the TXPCNCLK timing signal derived from the system clock. The message data is provided from the signal MSGDAT from the PCM highway signal MESSAGE when enable signals TR 0 EN, TR 1 EN, TR 2 EN and TR 3 EN from timing control logic 1401 are active. In further embodiments, MESSAGE may also include signals that enable registers depending upon an encryption rate or data rate. If the counter output is equal to one of the channel location addresses, the specified transmit message data in registers 1510 , 1511 , 1512 , 1513 are input to the convolutional encoders 1411 , 1412 , 1413 , 1414 shown in FIG. 14 .
[0267] The convolutional encoder enables the use of forward error correction (FEC) techniques, which are well known in the art. FEC techniques depend on introducing redundancy in generation of data in encoded form. Encoded data is transmitted and the redundancy in the data enables the receiver decoder device to detect and correct errors. One embodiment of the present invention employs convolutional encoding. Additional data bits are added to the data in the encoding process and are the coding overhead. The coding rate is expressed as the ratio of data bits transmitted to the total bits (code data+redundant data) transmitted and is called the rate “R” of the code.
[0268] Convolution codes are codes where each code bit is generated by the convolution of each new uncoded bit with a number of previously coded bits. The total number of bits used in the encoding process is referred to as the constraint length (K) of the code. In convolutional coding, data is clocked into a shift register of K bits length so that an incoming bit is clocked into the register, and it and the existing K−1 bits are convolutionally encoded to create a new symbol. The convolution process consists of creating a symbol consisting of a modulo-2 sum of a certain pattern of available bits, always including the first bit and the last bit in at least one of the symbols.
[0269] FIG. 16 shows the block diagram of a K=7, R=½ convolution encoder suitable for use as the encoder 1411 shown in FIG. 14 . This circuit encodes the TR 0 channel as used in one embodiment of the present invention. Seven-bit register 1601 with stages Q 1 through Q 7 uses the signal TXPNCLK to clock in TR 0 data when the TR 0 EN signal is asserted. The output value of stages Q 1 , Q 2 , Q 3 , Q 4 , Q 6 , and Q 7 are each combined using EXCLUSIVE-OR Logic 1602 , 1603 to produce respective I and Q channel FEC data for the TR 0 channel FECTR 0 D 1 and FECTR 0 DQ.
[0270] Two output symbol streams FECTR 0 D 1 and FECTR 0 DQ are generated. The FECTR 0 D 1 symbol stream is generated by EXCLUSIVE-OR logic 1602 of shift register outputs corresponding to bits 6 , 5 , 4 , 3 , and 0 , (Octal 171 ) and is designed as In phase component “I” of the transmit message channel data. The symbol stream FECTR 0 DQ is likewise generated by EXCLUSIVE-OR logic 1603 of shift register outputs from bits 6 , 4 , 3 , 1 and 0 , (Octal 133 ) and is designated as Quadrature component “Q” of the transmit message channel data. Two symbols are transmitted to represent a single encoded bit creating the redundancy necessary to enable error correction to take place on the receiving end.
[0271] Referring to FIG. 14 , the shift enable clock signal for the transmit message channel data is generated by the control timing logic 1401 . The convolutionally encoded transmit message channel output data for each channel is applied to the respective spreader 1420 , 1421 , 1422 , 1423 , 1424 which multiplies the transmit message channel data by its preassigned spreading code from code generator 1402 . This spreading code is generated by control 1303 as previously described, and is called a random pseudonoise signature code (PN-code).
[0272] The output signal of each spreader 1420 , 1421 , 1422 , 1423 , 1424 is a spread transmit data channel. The operation of the spreader is as follows: the spreading of channel output (I+jQ) multiplied by a random sequence (PNI+jPNQ) yields the in-phase component I of the result being composed of (I xor PNI) and (−Q xor PNQ). Quadrature component Q of the result is (Q xor PNI) and (I xor PNQ). Since there is no channel data input to the pilot channel logic (I=1, Q values are prohibited), the spread output signal for pilot channels yields the respective sequences PNI for I component and PNQ for Q component.
[0273] The combiner 1430 receives the I and Q spread transmit data channels and combines the channels into an I modem transmit data signal (TXIDAT) and a Q modem transmit data signal (TXQDAT). The I-spread transmit data and the Q-spread transmit data are added separately.
[0274] For an SU, the CDMA modem transmit section 1301 includes the FIR filters to receive the I and Q channels from the combiner to provide pulse shaping, close-in spectral control and x/sin(x) correction for the transmitted signal. Separate but identical FIR filters receive the I and Q spread transmit data streams at the chipping rate, and the output signal of each of the filters is at twice the chipping rate. The exemplary FIR filters are 28 tap even symmetrical filters, which upsample (interpolate) by 2. The upsampling occurs before the filtering, so that 28 taps refers to 28 taps at twice the chipping rate, and the upsampling is accomplished by setting every other sample to zero. Exemplary coefficients are shown in Table 11.
[0000]
TABLE 11
Coefficient Values
Coeff. No.:
0
1
2
3
4
5
6
7
8
9
10
11
12
13
Value:
3
−11
−34
−22
19
17
−32
−19
52
24
−94
−31
277
468
Coeff. No.
14
15
16
17
18
19
20
21
22
24
25
26
27
Value
277
−31
−94
24
52
−19
−32
17
19
−22
−34
−11
3
[0275] XXIV. CDMA Modem Receiver Section
[0276] Referring to FIGS. 9 and 12 , the RF receiver 950 of the present embodiment accepts analog input I and Q CDMA channels, which are transmitted to the CDMA modems 1210 , 1211 , 1212 , 1215 through the MIUs 931 , 932 , 933 from the VDC 940 . These I and Q CMDA channel signals are sampled by the CDMA modem receive section 1302 (shown in FIG. 13 ) and converted to I and Q digital receive message signals using an analog to digital (A/D) converter 1730 , shown in FIG. 17 . The sampling rate of the A/D converter of the exemplary embodiment of the present invention is equivalent to the despreading code rate. The I and Q digital receive message signals are then despread with correlators using six different complex spreading code sequences corresponding to the despreading code sequences of the four channels (TR 0 , TR 1 , TR 2 , TR 3 ), APC information and the pilot code.
[0277] Time synchronization of the receiver to the received signal is separated into two phases; there is an initial acquisition phase and then a tracking phase after the signal timing has been acquired. The initial acquisition is done by shifting the phase of the locally generated pilot code sequence relative to the received signal and comparing the output of the pilot despreader to a threshold. The method used is called sequential search. Two thresholds (match and dismiss) are calculated from the auxiliary despreader. Once the signal is acquired, the search process is stopped and the tracking process begins. The tracking process maintains the code generator 1304 (shown in FIGS. 13 and 17 ) used by the receiver in synchronization with the incoming signal. The tracking loop used is the delay-locked loop (DLL) and is implemented in the acquisition & track 1701 and the IPM 1702 blocks of FIG. 17 .
[0278] In FIG. 13 , the modem controller 1303 implements the phase lock loop (PLL) as a software algorithm in SW PLL logic 1724 of FIG. 17 that calculates the phase and frequency shift in the received signal relative to the transmitted signal. The calculated phase shifts are used to derotate the phase shifts in rotate and combine blocks 1718 , 1719 , 1720 , 1721 of the multipath data signals for combining to produce output signals corresponding to receive channels TR 0 ′, TR 1 ′, TR 2 ′, TR 3 ′. The data is then Viterbi decoded in Viterbi decoders 1713 , 1714 , 1715 , 1716 to remove the convolutional encoding in each of the received message channels.
[0279] FIG. 17 indicates that the Code Generator 1304 provides the code sequences Pn i (t), i=1, 2, . . . I used by the receive channel despreaders 1703 , 1704 , 1705 , 1706 , 1707 , 1708 , 1709 . The code sequences generated are timed in response to the SYNK signal of the system clock signal and are determined by the CCNTRL signal from the modem controller 1303 shown in FIG. 13 . Referring to FIG. 17 , the CDMA modem receiver section 1302 includes adaptive matched filter (AMF) 1710 , channel despreaders 1703 , 1704 , 1705 , 1706 , 1707 , 1708 , 1709 , pilot AVC 1711 , auxiliary AVC 1712 , Viterbi decoders 1713 , 1714 , 1715 , 1716 , modem output interface (MOI) 1717 , rotate and combine logic 1718 , 1719 , 1720 , 1721 , AMF weight generator 1722 , and quantile estimation logic 1723 and 1733 .
[0280] In another embodiment of the invention, the CDMA modem receiver also includes a bit error integrator to measure the BER of the channel and idle code insertion logic between the Viterbi decoders 1713 , 1714 , 1715 , 1716 and the MOI 1717 to insert idle codes in the event of loss of the message data.
[0281] The AMF 1710 resolves multipath interference introduced by the air channel. The exemplary AMF 1710 uses an 11 stage complex FIR filter as shown in FIG. 18 . The received I and Q digital message signals are received at the register 1820 from the A/D 1730 of FIG. 17 and are multiplied in multipliers 1801 , 1802 , 1803 , 1810 , 1811 by I and Q channel weights W 1 to W 11 received from AMF weight generator 1722 of FIG. 17 . In the exemplary embodiment, the A/D 1730 provides the I and Q digital receive message signal data as 2's complement values, 6 bits for 1 and 6 bits for Q which are clocked through an 11 stage shift register 1820 responsive to the receive spreading-code clock signal RXPNCLK. The signal RXPNCLK is generated by the timing section 1401 of code generation logic 1304 . Each stage of the shift register is tapped and complex multiplied in the multipliers 1801 , 1802 , 1803 , 1810 , 1811 by individual (6-bit I and 6-bit Q) weight values to provide 11 tap-weighted products which are summed in adder 1830 , and limited to 7-bit I and 7-bit Q values.
[0282] The CDMA modem receive section 1302 (shown in FIG. 13 ) provides independent channel despreaders 1703 , 1704 , 1705 , 1706 , 1707 , 1708 , 1709 (shown in FIG. 17 ) for despreading the message channels. The described embodiment despreads 7 message channels, each despreader accepting a 1-bit I by 1-bit Q despreading code signal to perform a complex correlation of this code against a 8-bit I by 8-bit Q data input. The 7 despreaders correspond to the 7 channels: traffic channel 0 (TR 0 ′), TR 1 ′, TR 2 ′, TR 3 ′, AUX (a spare channel), APC and pilot (PLT).
[0283] The pilot AVC 1711 shown in FIG. 19 receives the I and Q pilot spreading code sequence values PCI and PCQ into shift register 1920 responsive to the timing signal RXPNCLK, and includes 11 individual despreaders 1901 through 1911 each correlating the I and Q digital receive message signal data with a one chip delayed version of the same pilot code sequence. Signals OE 1 , OE 2 , . . . OE 11 are used by the modem control 1303 to enable the despreading operation. The output signals of the despreaders are combined in combiner 1920 forming correlation signal DSPRDAT of the Pilot AVC 1711 , which is received by the ACQ & track logic 1701 (shown in FIG. 17 ), and ultimately by modem controller 1303 (shown in FIG. 13 ). The ACQ & track logic 1701 uses the correlation signal value to determine if the local receiver is synchronized with its remote transmitter.
[0284] The auxiliary AVC 1712 also receives the I and Q digital receive message signal data and, in the described embodiment, includes four separate despreaders 2001 , 2002 , 2003 , 2004 as shown in FIG. 20 . Each despreader receives and correlates the I and Q digital receive message data with delayed versions of the same despreading code sequence PARI and PARQ which are provided by code generator 1304 input to and contained in shift register 2020 . The output signals of the despreaders 2001 , 2002 , 2003 , 2004 are combined in combiner 2030 which provides noise correlation signal ARDSPRDAT. The auxiliary AVC spreading code sequence does not correspond to any transmit spreading code sequence of the system. Signals OE 1 , OE 2 , . . . OE 4 are used by the modem control 1303 to enable the despreading operation. The Auxiliary AVC 1712 provides a noise correlation signal ARDSPRDAT from which quantile estimates are calculated by the quantile estimation logic 1733 , and provides a noise level measurement to the ACQ & Track logic 1701 (shown in FIG. 17 ) and modem controller 1303 (shown in FIG. 13 ).
[0285] Each despread channel output signal corresponding to the received message channels TR 0 ′, TR 1 ′, TR 2 ′, and TR 3 ′ is input to a corresponding Viterbi decoder 1713 , 1714 , 1715 , 1716 shown in FIG. 17 which performs forward error correction on convolutionally encoded data. The Viterbi decoders of the exemplary embodiment have a constraint length of K=7 and a rate of R=½. The decoded despread message channel signals are transferred from the CDMA modem to the PCM Highway 1201 through the MOI 1717 . The operation of the MOI is essentially the same as the operation of the MISR of the transmit section 1301 (shown in FIG. 13 ) except in reverse.
[0286] The CDMA modem receiver section 1302 implements several different algorithms during different phases of the acquisition, tracking and despreading of the receive CDMA message signal.
[0287] When the received signal is momentarily lost (or severely degraded) the idle code insertion algorithm inserts idle codes in place of the lost or degraded receive message data to prevent the user from hearing loud noise bursts on a voice call. The idle codes are sent to the MOI 1717 (shown in FIG. 17 ) in place of the decoded message channel output signal from the Viterbi decoders 1713 , 1714 , 1715 , 1716 . The idle code used for each traffic channel is programmed by the Modem Controller 1303 by writing the appropriate pattern IDLE to the MOI, which in the present embodiment is a 8 bit word for a 64 kbs stream, 4 bit word for a 32 kbs stream.
[0288] XXV. Modem Algorithms for Acquisition and Tracking of Received Pilot Signal
[0289] The acquisition and tracking algorithms are used by the receiver to determine the approximate code phase of a received signal, synchronize the local modem receiver despreaders to the incoming pilot signal, and track the phase of the locally generated pilot code sequence with the received pilot code sequence. Referring to FIGS. 13 and 17 , the algorithms are performed by the modem controller 1303 , which provides clock adjust signals to code generator 1304 . These adjust signals cause the code generator for the despreaders to adjust locally generated code sequences in response to measured output values of the pilot rake 1711 and quantile values from quantile estimation logic 1733 . Quantile values are noise statistics measured from the in-phase and quadrature channels from the output values of the AUX vector correlator 1712 (shown in FIG. 17 ). Synchronization of the receiver to the received signal is separated into two phases; an initial acquisition phase and a tracking phase. The initial acquisition phase is accomplished by clocking the locally generated pilot spreading code sequence at a higher or lower rate than the received signal's spreading code rate, sliding the locally generated pilot spreading code sequence and performing sequential probability ratio test (SPRT) on the output of the pilot vector correlator 1711 . The tracking phase maintains the locally generated spreading code pilot sequence in synchronization with the incoming pilot signal. Details of the quantile estimation logic 1723 and 1733 may be found in U.S. Pat. No. 5,535,238 entitled “Spread Spectrum Adaptive Power Control Communications System and Method” by Donald L. Schilling et al., which is incorporated by reference herein.
[0290] The SU cold acquisition algorithm is used by the SU CDMA modem when it is first powered up, and therefore has no knowledge of the correct pilot spreading code phase, or when an SU attempts to reacquire synchronization with the incoming pilot signal but has taken an excessive amount of time. The cold acquisition algorithm is divided into two sub-phases. The first subphase consists of a search over the length 233415 code used by the FBCH. Once this sub-code phase is acquired, the pilot's 233415×128 length code is known to within an ambiguity of 128 possible phases. The second subphase is a search of these remaining 128 possible phases. In order not to lose synch with the FBCH, in the second phase of the search, it is desirable to switch back and forth between tracking of the FBCH code and attempting acquisition of the pilot code.
[0291] The RCS acquisition of short access pilot (SAXPT) algorithm is used by an RCS CDMA modem to acquire the SAXPT pilot signal of an SU. Additional details of this technique are described in Section XII hereinafter entitled “A Method Of Controlling Initial Power Ramp-Up In CDMA Systems By Using Short Codes”. The algorithm is a fast search algorithm because the SAXPT is a short code sequence of length N, where N=chips/symbol, and ranges from 45 to 195, depending on the system's bandwidth. The search cycles through all possible phases until acquisition is complete.
[0292] The RCS acquisition of the long access pilot (LAXPT) algorithm begins immediately after acquisition of SAXPT. The SU's code phase is known within a multiple of a symbol duration, so in the exemplary embodiment of the invention there may be 7 to 66 phases to search within the round trip delay from the RCS. This boundary is a result of the SU pilot signal being synchronized to the RCS global pilot signal.
[0293] The re-acquisition algorithm begins when loss of lock (LOL) occurs. A Z-search algorithm is used to speed the process on the assumption that the code phase has not drifted far from where it was the last time the system was locked. The RCS uses a maximum width of the Z-search windows bounded by the maximum round trip propagation delay.
[0294] The pre-track period immediately follows the acquisition or re-acquisition algorithms and immediately precedes the tracking algorithm. Pre-track is a fixed duration period during which the receive data provided by the modem is not considered valid. The pre-track period allows other modem algorithms, such as those used by the SW PLL 1724 , acquisition and tracking circuit 1701 , AMF weight generator 1722 , to prepare and adapt to the current channel. The pre-track period is two parts. The first part is the delay while the code tracking loop pulls in. The second part is the delay while the AMF tap weight calculations are performed by the AMF weight generator 1722 to produce settled weighting coefficients. Also in the second part of the pre-track period, the carrier tracking loop is allowed to pull in by the SW PLL 1724 , and the scalar quantile estimates are performed in the quantile estimation logic 1723 .
[0295] The tracking process is entered after the pre-track period ends. This process is actually a repetitive cycle and is the only process phase during which receive data provided by the modem may be considered valid. The following operations are performed during this phase: AMF tap weight update, carrier tracking, code tracking, vector quantile update, scalar quantile update, code lock check, derotation and symbol summing and power control (forward and reverse)
[0296] If LOL is detected, the modem receiver terminates the track algorithm and automatically enters the reacquisition algorithm. In the SU, a LOL causes the transmitter to be shut down. In the RCS, LOL causes forward power control to be disabled with the transmit power held constant at the level immediately prior to loss of lock. It also causes the return power control information being transmitted to assume a “010101 . . . ” pattern, causing the SU to hold its transmit power constant. This can be performed using the signal lock check function which generates the reset signal to the acquisition and tracking circuit 1701 .
[0297] Two sets of quantile statistics are maintained, one by the vector quantile estimation logic 1733 and the other by the scalar quantile estimation logic 1723 . Both are used by the modem controller 1303 . The first set is the “vector” quantile information, so named because it is calculated from the vector of four complex values generated by the AUX AVC receiver 1712 . The second set is the scalar quantile information, which is calculated from the single complex value AUX signal that is output from the AUX despreader 1707 . The two sets of information represent different sets of noise statistics used to maintain a pre-determined probability of false alarm (Pfa). The vector quantile data is used by the acquisition and reacquisition algorithms implemented by the modem controller 1303 to determine the presence of a received signal in noise, and the scalar quantile information is used by the code lock check algorithm.
[0298] For both the vector and scalar cases, quantile information consists of calculated values of lambda0 through lambda2, which are boundary values used to estimate the probability distribution function (p.d.f.) of the despread receive signal and determine whether the modem is locked to the PN code. The aux_power value used in the following C-subroutine is the magnitude squared of the AUX signal output of the scalar correlator array for the scalar quantiles, and the sum of the magnitudes squared for the vector case. In both cases the quantiles are then calculated using the following C-subroutine:
[0000] for (n = 0; n < 3; n++) { lambda [n] += (lambda [n] < Aux_Power) ? CG[n] : GM[n]; }
where CG[n] are positive constants and GM[n] are negative constants, (different values are used for scalar and vector quantiles).
[0299] During the acquisition phase, the search of the incoming pilot signal with the locally generated pilot code sequence employs a series of sequential tests to determine if the locally generated pilot code has the correct code phase relative to the received signal. The search algorithms use the sequential probability ratio test (SPRT) to determine whether the received and locally generated code sequences are in phase. The speed of acquisition is increased by parallelism resulting from having a multi-fingered receiver. For example, in the described embodiment of the invention the main pilot rake 1711 has a total of 11 fingers representing a total phase period of 11 chip periods. For acquisition 8 separate SPRTs are implemented, with each SPRT observing a 4 chip window. Each window is offset from the previous window by one chip, and in a search sequence any given code phase is covered by 4 windows. If all 8 of the SPRT tests are rejected, then the set of windows is moved by 8 chips. If any of the SPRT's is accepted, then the code phase of the locally generated pilot code sequence is adjusted to attempt to center the accepted SPRT's phase within the pilot AVC. It is likely that more than one SPRT reaches the acceptance threshold at the same time. A table lookup is used to cover all 256 possible combinations of accept/reject and the modem controller uses the information to estimate the correct center code phase within the pilot rake 1711 . Each SPRT is implemented as follows (all operations occur at 64 k symbol rate): Denote the fingers' output level values as I_Finger[n] and Q_Finger[n], where n=0.10 (inclusive, 0 is earliest (most advanced) finger), then the power of each window is:
[0000]
Power
Window
[
i
]
=
∑
n
=
0
10
(
I_Finger
2
[
n
]
+
Q_Finger
2
[
n
]
)
[0000] To implement the SPRT's the modem controller then performs for each of the windows the following calculations which are expressed as a pseudo-code subroutine:
[0000] /* find bin for Power */ tmp = SIGMA[0]; for (k = 0; k< 3; k++) { if (Power > lambda [k]) tmp = SIGMA[k+1]; } test_statistic += tmp; /* update statistic */ if(test_statistic > ACCEPTANCE_THRESHOLD)you've got ACQ; else if (test_statistic < DISMISSAL_THRESHOLD) { forget this code phase; } else keep trying - get more statistics;
where lambda[k] are as defined in the above section on quantile estimation, and SIGMA[k], ACCEPTANCE_THRESHOLD and DISMISSAL_THRESHOLD are predetermined constants. Note that SIGMA[K] is negative for low values of k, and positive for right values of k, such that the acceptance and dismissal thresholds can be constants rather than a function of how many symbols worth of data have been accumulated in the statistic.
[0300] The modem controller determines which bin delimited by the values of lambda[k] the power level falls into which allows the modem controller to develop an approximate statistic.
[0301] For the present algorithm, the control voltage is formed as ε=y T By, where y is a vector formed from the complex valued output values of the pilot vector correlator 1711 , and B is a matrix consisting of the constant values pre-determined to maximize the operating characteristics while minimizing the noise as described previously with reference to the quadratic detector.
[0302] To understand the operation of the quadratic detector, it is useful to consider the following. A spread spectrum signal, s(t) is passed through a multipath channel with an impulse response h c (t). The baseband spread signal is described by Equation (30):
[0000]
s
(
t
)
=
∑
i
C
i
p
(
t
-
i
T
c
)
Equation
(
30
)
[0000] where C i is a complex spreading code symbol, p(t) is a predefined chip pulse and T c is the chip time spacing, where T c =1/R c and R c is the chip rate.
[0303] The received baseband signal is represented by Equation (31):
[0000]
r
(
t
)
=
∑
i
C
i
q
(
t
-
i
T
c
-
τ
)
+
n
(
t
)
Equation
(
31
)
[0000] where q(t)=p(t)*h c (t), t is an unknown delay and n(t) is additive noise. The received signal is processed by a filter, h R (t), so the waveform, x(t), to be processed is given by Equation (32):
[0000]
x
(
t
)
=
∑
i
C
i
f
(
t
-
i
T
c
-
τ
)
+
x
(
t
)
Equation
(
32
)
[0000] where f(t)=q(t)*h R (t) and z(t)=n(t)*h R (t).
[0304] In the exemplary receiver, samples of the received signal are taken at the chip rate, that is to say, 1/T c . These samples, x(mT c +τ′), are processed by an array of correlators that compute, during the r th correlation period, the quantities given by Equation (33):
[0000]
v
k
(
r
)
=
∑
m
=
rL
rL
+
L
-
1
x
(
mT
c
+
τ
′
)
C
m
+
k
*
Equation
(
33
)
[0000] These quantities are composed of a noise component w k (r) and a deterministic component y k (r) given by Equation (34):
[0000] y k (r) =E└v k (r) ┘=Lf ( kT c +τ′−τ) Equation (34)
[0000] In the sequel, the time index r may be suppressed for ease of writing, although it is to be noted that the function f(t) changes slowly with time.
[0305] The samples are processed to adjust the sampling phase, τ′, in an optimum fashion for further processing by the receiver, such as matched filtering. This adjustment is described below. To simplify the representation of the process, it is helpful to describe it in terms of the function f(t+τ), where the time-shift, τ, is to be adjusted. It is noted that the function f(t+τ) is measured in the presence of noise. Thus, it may be problematical to adjust the phase τ′ based on measurements of the signal f(t+τ). To account for the noise, the function v(τ): v(t)=f(t)+m(t) is introduced, where the term m(t) represents a noise process. The system processor may be derived based on considerations of the function v(t).
[0306] The process is non-coherent and therefore is based on the envelope power function |v(t+τ)| 2 . The functional e(τ′) given in Equation (35) is helpful for describing the process:
[0000] e (τ′)=∫ 0 −∞ |v ( t +τ′−τ)| 2 dt−∫ ∞ 0 |v ( t +τ′−τ)| 2 dt Equation (35)
[0000] The shift parameter is adjusted for e(τ′)=0, which occurs when the energy on the interval (−∞, τ′−τ] equals that on the interval [τ′−τ, ∞). The error characteristic is monotonic and therefore has a single zero crossing point. This is the desirable quality of the functional. A disadvantage of the functional is that it is ill-defined because the integrals are unbounded when noise is present. Nevertheless, the functional e(τ′) may be cast in the form given by Equation (36):
[0000] e (τ′)=∫ 0 −∞ w ( t )| v ( t +τ′−τ)| 2 dt Equation (36)
[0000] where the characteristic function w(t) is equal to sgn(t), the signum function.
[0307] To optimize the characteristic function w(t), it is helpful to define a figure of merit, F, as set forth in Equation (37):
[0000]
F
=
[
e
(
τ
0
′
+
T
A
)
-
e
(
τ
0
′
-
T
A
)
]
2
_
VAR
{
e
(
τ
0
′
)
}
Equation
(
37
)
[0000] The numerator of F is the numerical slope of the mean error characteristic on the interval [−T A ,T A ] surrounding the tracked value, τ 0 ′. The statistical mean is taken with respect to the noise as well as the random channel, h c (t). It is desirable to specify a statistical characteristic of the channel in order to perform this statistical average. For example, the channel may be modeled as a wide sense stationary uncorrelated scattering (WSSUS) channel with impulse response h c (t) and a white noise process U(t) that has an intensity function g(t) as shown in Equation (38):
[0000] h c ( t )=√{square root over ( g ( t ))} U ( t ) Equation (38)
[0000] The variance of e(τ) is computed as the mean square value of the fluctuation:
[0000] e′ (τ)= e (τ)−< e (τ)> Equation (39)
[0000] where <e(τ)> is the average of e(τ) with respect to the noise.
[0308] Optimization of the figure of merit F with respect to the function w(t) may be carried out using well-known variational methods of optimization. Once the optimal w(t) is determined, the resulting processor may be approximated accurately by a quadratic sample processor which is derived as follows. By the sampling theorem, the signal v(t), bandlimited to a bandwidth W may be expressed in terms of its samples as shown in Equation (40):
[0000] v ( t )=Σ v ( k/W )sin c [( Wt−k )π] Equation (40)
[0000] substituting this expansion into Equation (36) results in an infinite quadratic form in the samples v(k/W+τ′−τ). Making the assumption that the signal bandwidth equals the chip rate allows the use of a sampling scheme that is clocked by the chip clock signal to be used to obtain the samples. These samples, v k are represented by Equation (41):
[0000] v k =v ( kT c +τ′−τ) Equation (41)
[0000] This assumption leads to a simplification of the implementation. It is valid if the aliasing error is small.
[0309] In practice, the quadratic form that is derived is truncated. An example normalized B matrix is given below in Table 12. For this example, an exponential delay spread profile g(t)=exp(−t/τ) is assumed with τ equal to one chip. An aperture parameter T A equal to one and one-half chips has also been assumed. The underlying chip pulse has a raised cosine spectrum with a 20% excess bandwidth.
[0000] TABLE 12 Example B Matrix 0 0 0 0 0 0 0 0 0 0 0 0 0 −0.1 0 0 0 0 0 0 0 0 0 −0.1 0.22 0.19 −0.19 0 0 0 0 0 0 0 0 0.19 1 0.45 −0.2 0 0 0 0 0 0 0 −0.19 0.45 0.99 0.23 0 0 0 0 0 0 0 0 −0.2 0.23 0 −0.18 0.17 0 0 0 0 0 0 0 0 −0.18 −0.87 −0.42 0.18 0 0 0 0 0 0 0 0.17 −0.42 −0.92 −0.16 0 0 0 0 0 0 0 0 0.18 −0.16 −0.31 0 0 0 0 0 0 0 0 0 0 0 −0.13 0 0 0 0 0 0 0 0 0 0 0 0
Code tracking is implemented via a loop phase detector that is implemented as follows. The vector y is defined as a column vector which represents the 11 complex output level values of the pilot AVC 1711 , and B denotes an 11×11 symmetric real valued coefficient matrix with pre-determined values to optimize performance with the non-coherent pilot AVC output values y. The output signal ε of the phase detector is given by Equation (42):
[0000] ε=y T By Equation (42)
[0000] The following calculations are then performed to implement a proportional plus integral loop filter and the VCO:
[0000] x[n]=x[n− 1]+βε
[0000] z[n]=z[n− 1 ]+x[n]+αε
[0000] for β and α which are constants chosen from modeling the system to optimize system performance for the particular transmission channel and application, and where x[n] is the loop filter's integrator output value and z[n] is the VCO output value. The code phase adjustments are made by the modem controller in the following C-subroutine:
[0000]
if (z > zmx) {
delay phase 1/16 chip;
z −= zmax;
} else if (z < −zmax) {
advance phase 1/16 chip;
z += zmax;
}
[0310] A different delay phase could be used in the above pseudo-code consistant with the present invention.
[0311] The AMF tap-weight update algorithm of the AMF weight generator 1722 occurs periodically to de-rotate and scale the phase of each finger value of the pilot rake 1711 by performing a complex multiplication of the pilot AVC finger value with the complex conjugate of the current output value of the carrier tracking loop and applying the product to a low pass filter and form the complex conjugate of the filter values to produce AMF tap-weight values, which are periodically written into the AMF filters of the CDMA modem.
[0312] The lock check algorithm, shown in FIG. 17 , is implemented by the modem controller 1303 performing SPRT operations on the output signal of the scalar correlator array. The SPRT technique is the same as that for the acquisition algorithms, except that the acceptance and rejection thresholds are changed to increase the probability of detection of lock.
[0313] Carrier tracking is accomplished via a second order loop that operates on the pilot output values of the scalar correlated array. The phase detector output is the hard limited version of the quadrature component of the product of the (complex valued) pilot output signal of the scalar correlated array and the VCO output signal. The loop filter is a proportional plus integral design. The VCO is a pure summation, accumulated phase error Φ, which is converted to the complex phaser cos Φ+j sin Φ using a look-up table in memory.
[0314] The previous description of acquisition and tracking algorithm focuses on a non-coherent method because the acquisition and tracking algorithm described requires non-coherent acquisition followed by non-coherent tracking because during acquisition a coherent reference is not available until the AMF, pilot AVC, aux AVC, and DPLL are in an equilibrium state. However, it is known in the art that coherent tracking and combining is always optimal because in non-coherent tracking and combining the output phase information of each pilot AVC finger is lost. Consequently, another embodiment of the invention employs a two step acquisition and tracking system, in which the previously described non-coherent acquisition and tracking algorithm is implemented first, and then the algorithm switches to a coherent tracking method. The coherent combining and tracking method is similar to that described previously, except that the error signal tracked is of the form:
[0000] ε=y T Ay Equation (43)
[0000] where y is defined as a column vector which represents the 11 complex output level values of the pilot AVC 1711 , and A denotes an 11×11 symmetric real valued coefficient matrix with pre-determined values to optimize performance with the coherent pilot AVC outputs y. An exemplary A matrix is shown below.
[0000]
A
=
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-
1
0
0
0
0
0
0
0
0
0
0
0
-
1
0
0
0
0
0
0
0
0
0
0
0
-
1
0
0
0
0
0
0
0
0
0
0
0
-
1
0
0
0
0
0
0
0
0
0
0
0
-
1
Equation
(
44
)
[0315] Referring to FIG. 9 , the video distribution controller board (VDC) 940 of the RCS is connected to each MIU 931 , 932 , 933 and the RF transmitters/receivers 950 . The VDC 940 is shown in FIG. 21 . The data combiner circuitry (DCC) 2150 includes a data demultiplexer 2101 , data summer 2102 , FIR filters 2103 , 2104 and a driver 2111 . The DCC 2150 : 1) receives the weighted CDMA modem I and Q data signal MDAT from each of the MIUs, 931 , 932 , 933 , 2) sums the I and Q data with the digital bearer channel data from each MIU 931 , 932 , 933 , 3) and sums the result with the broadcast data message signal BCAST and the global pilot spreading code GPILOT provided by the master MIU modem 1210 , 4) band shapes the summed signals for transmission, and 5) produces analog data signal for transmission to the RF transmitter/receiver.
[0316] FIR filters 2103 , 2104 are used to modify the MIU CDMA transmit I and Q modem data before transmission. The WAC transfers FIR filter coefficient data through the serial port link 912 through the VDC controller 2120 and to the FIR filters 2103 , 2104 . Each FIR filter 2103 , 2104 is configured separately. The FIR Filters 2103 , 2104 employ upsampling to operate at twice the chip rate so zero data values are sent after every MIU CDMA transmit modem DATI and DATQ value to produce FTXI and FTXQ.
[0317] The VDC 940 distributes the AGC signal AGCDATA from the AGC 1750 of the MIUs 931 , 932 , 933 to the RF transmitter/receiver 950 through the distribution interface (DI) 2110 . The VDC DI 2110 receives data RXI and RXQ from the RF transmitter/receiver and distributes the signal as VDATAI and VDATAQ to MIUs 931 , 932 , 933 .
[0318] Referring to FIG. 21 , the VDC 940 also includes a VDC controller 2120 which monitors status and fault information signals MIUSTAT from MIUs and connects to the serial link 912 and HSBS 970 to communicate with WAC 920 shown in FIG. 9 . The VDC controller 2120 includes a microprocessor, such as an Intel 8032 microcontroller, an oscillator (not shown) providing timing signals, and memory (not shown). The VDC controller memory includes a flash PROM (not shown) to contain the controller program code for the 8032 microprocessor, and an SRAM (not shown) to contain the temporary data written to and read from memory by the microprocessor.
[0319] Referring to FIG. 9 , the present invention includes a RF transmitter/receiver 950 and power amplifier section 960 . Referring to FIG. 22 , the RF transmitter/receiver 950 is divided into three sections: the transmitter module 2201 , the receiver module 2202 , and the frequency synthesizer 2203 . Frequency synthesizer 2203 produces a transmit carrier frequency TFREQ and a receive carrier frequency RFREQ in response to a frequency control signal FREQCTRL received from the WAC 920 on the serial link 912 . In the transmitter module 2201 , the input analog I and Q data signals TXI and TXQ from the VDC are applied to the quadrature modulator 2220 , which also receives a transmit carrier frequency signal TFREQ from the frequency synthesizer 2203 to produce a quadrature modulated transmit carrier signal TX. The analog transmit carrier modulated signal, an upconverted RF signal, TX is then applied to the transmit power amplifier 2252 of the power amplifier 960 . The amplified transmit carrier signal is then passed through the high power passive components (HPPC) 2253 to the Antenna 2250 , which transmits the upconverted RF signal to the communication channel as a CDMA RF signal. In one embodiment of the invention, the transmit power amplifier 2252 comprises eight amplifiers of approximately 60 watts peak-to-peak each.
[0320] The HPPC 2253 comprises a lightning protector, an output filter, a 10 dB directional coupler, an isolator, and a high power termination attached to the isolator.
[0321] A receive CDMA RF signal is received at the antenna 2250 from the RF channel and passed through the HPPC 2253 to the receive power amplifier 2251 . The receive power amplifier 2251 includes, for example, a 30 watt power transistor driven by a 5 watt transistor. The RF receive module 2202 has quadrature modulated receive carrier signal RX from the receive power amplifier. The receive module 2202 includes a quadrature demodulator 2210 which takes the receive carrier modulated signal RX and the receive carrier frequency signal RFREQ from the frequency synthesizer 2203 , synchronously demodulates the carrier and provides analog I and Q channels. These channels are filtered to produce the signals RXI and RXQ, which are transferred to the VDC 940 .
[0322] XXVI. The Subscriber Unit
[0323] FIG. 23 shows the subscriber unit (SU) of one embodiment of the present invention. As shown, the SU includes an RF section 2301 including a RF modulator 2302 , RF demodulator 2303 and splitter/isolator 2304 which receive global and assigned logical channels including traffic and control messages and global pilot signals in the forward link CDMA RF channel signal, and transmit assigned channels and reverse pilot signals in the reverse link CDMA RF channel. The forward and reverse links are received and transmitted respectively through antenna 2305 . The RF section employs, in one exemplary embodiment, a conventional dual conversion superheterodyne receiver having a synchronous demodulator responsive to the signal ROSC. Selectivity of such a receiver is provided by a 70 MHz transversal SAW filter (not shown). The RF modulator includes a synchronous modulator (not shown) responsive to the carrier signal TOSC to produce a quadrature modulated carrier signal. This signal is stepped up in frequency by an offset mixing circuit (not shown).
[0324] The SU further includes a subscriber line interface 2310 , including the functionality of a control (CC) generator, a data interface 2320 , an ADPCM encoder 2321 , an ADPCM decoder 2322 , an SU controller 2330 , an SU clock signal generator 2331 , memory 2332 and a CDMA modem 2340 , which is essentially the same as the CDMA modem 1210 described above with reference to FIG. 13 . It is noted that data interface 2320 , ADPCM encoder 2321 and ADPCM decoder 2322 are typically provided as a standard ADPCM encoder/decoder chip.
[0325] The forward link CDMA RF channel signal is applied to the RF demodulator 2303 to produce the forward link CDMA signal. The forward link CDMA signal is provided to the CDMA modem 2340 , which acquires synchronization with the global pilot signal, produces global pilot synchronization signal to the clock 2331 , to generate the system timing signals, and despreads the plurality of logical channels. The CDMA modem 2340 also acquires the traffic messages RMESS and control messages RCTRL and provides the traffic message signals RMESS to the data interface 2320 and receive control message signals RCTRL to the SU controller 2330 .
[0326] The receive control message signals RCTRL include a subscriber identification signal, a coding signal and bearer modification signals. The RCTRL may also include control and other telecommunication signaling information. The receive control message signal RCTRL is applied to the SU controller 2330 , which verifies that the call is for the SU from the subscriber identification value derived from RCTRL. The SU controller 2330 determines the type of user information contained in the traffic message signal from the coding signal and bearer rate modification signal. If the coding signal indicates the traffic message is ADPCM coded, the traffic message RVMESS is sent to the ADPCM decoder 2322 by sending a select message to the data interface 2320 . The SU controller 2330 outputs an ADPCM coding signal and bearer rate signal derived from the coding signal to the ADPCM decoder 2322 . The traffic message signal RVMESS is the input signal to the ADPCM decoder 2322 , where the traffic message signal is converted to a digital information signal RINF in response to the values of the input ADPCM coding signal.
[0327] If the SU controller 2330 determines the type of user information contained in the traffic message signal from the coding signal is not ADPCM coded, then RDMESS passes through the ADPCM encoder transparently. The traffic message RDMESS is transferred from the data interface 2320 directly to the interface controller (IC) 2312 of the subscriber line interface 2310 .
[0328] The digital information signal RINF or RDMESS is applied to the subscriber line interface 2310 , including an interface controller (IC) 2312 and line interface (LI) 2313 . For the exemplary embodiment the IC is an extended PCM interface controller (EPIC) and the LI is a subscriber line interface circuit (SLIC) for POTS which corresponds to RINF type signals and an ISDN Interface for ISDN which corresponds to RDMESS type signals. The EPIC and SLIC circuits are well known in the art. The subscriber line interface 2310 converts the digital information signal RINF or RDMESS to the user defined format. The user defined format is provided to the IC 2312 from the SU Controller 2330 . The LI 2310 includes circuits for performing such functions as A-law or μ-law conversion, generating dial tone and generating or interpreting signaling bits. The line interface also produces the user information signal to the SU user 2350 as defined by the subscriber line interface, for example POTS voice, voiceband data or ISDN data service.
[0329] For a reverse link CDMA RF channel, a user information signal is applied to the LI 2313 of the subscriber line interface 2310 , which outputs a service type signal and an information type signal to the SU controller. The IC 2312 of the subscriber line interface 2310 produces a digital information signal TINF which is the input signal to the ADPCM encoder 2321 if the user information signal is to be ADPCM encoded, such as for POTS service. For data or other non-ADPCM encoded user information, the IC 2312 passes the data message TDMESS directly to the data interface 2320 . The call control module (CC), including in the subscriber line interface 2310 , derives call control information from the user information signal, and passes the call control information CCINF to the SU controller 2330 . The ADPCM encoder 2321 also receives coding signal and bearer modification signals from the SU controller 2330 and converts the input digital information signal into the output message traffic signal TVMESS in response to the coding and bearer modification signals. The SU controller 2330 also outputs the reverse control signal which includes the coding signal call control information, and bearer channel modification signal, to the CDMA modem. The output message signal TVMESS is applied to the data interface 2320 . The data interface 2320 sends the user information to the CDMA modem 2340 as transmit message signal TMESS. The CDMA modem 2340 spreads the output message and reverse control channels TCTRL received from the SU controller 2330 and produces the reverse link CDMA signal. The reverse link CDMA signal is provided to the RF transmit section 2301 and modulated by the RF modulator 2302 to produce the output reverse link CDMA RF channel signal transmitted from antenna 2305 .
[0330] XXVII. Call Connection and Establishment Procedure
[0331] The process of bearer channel establishment consists of two procedures: the call connection process for a call connection incoming from a remote call processing unit such as an RDU (incoming call connection), and the call connection process for a call outgoing from the SU (outgoing call connection). Before any bearer channel can be established between an RCS and a SU, the SU must register its presence in the network with the remote call processor such as the RDU. When the off-hook signal is detected by the SU, the SU not only begins to establish a bearer channel, but also initiates the procedure for an RCS to obtain a terrestrial link between the RCS and the remote processor. As incorporated herein by reference, the process of establishing the RCS and RDU connection is detailed in the DECT V5.1 standard.
[0332] For the incoming call connection procedure shown in FIG. 24 , first 2401 , the WAC 920 (shown in FIG. 9 ) receives, via one of the MUXs 905 , 906 and 907 , an incoming call request from a remote call processing unit. This request identifies the target SU and that a call connection to the SU is desired. The WAC periodically outputs the SBCH channel with paging indicators for each SU and periodically outputs the FBCH traffic lights for each access channel. In response to the incoming call request, the WAC, at step 2420 , first checks to see if the identified SU is already active with another call. If so, the WAC returns a busy signal for the SU to the remote processing unit through the MUX, otherwise the paging indicator for the channel is set.
[0333] Next, at step 2402 , the WAC checks the status of the RCS modems and, at step 2421 , determines whether there is an available modem for the call. If a modem is available, the traffic lights on the FBCH indicate that one or more AXCH channels are available. If no channel is available after a certain period of time, then the WAC returns a busy signal for the SU to the remote processing unit through the MUX. If an RCS modem is available and the SU is not active (in sleep mode), the WAC sets the paging indicator for the identified SU on the SBCH to indicate an incoming call request. Meanwhile, the access channel modems continuously search for the short access pilot signal (SAXPT) of the SU.
[0334] At step 2403 , an SU in sleep mode periodically enters awake mode. In awake mode, the SU modem synchronizes to the downlink pilot signal, waits for the SU modem AMF filters and phase locked loop to settle, and reads the paging indicator in the slot assigned to it on the SBCH to determine if there is a call for the SU 2422 . If no paging indicator is set, the SU halts the SU modem and returns to sleep mode. If a paging indicator is set for an incoming call connection, the SU modem checks the service type and traffic lights on FBCH for an available AXCH.
[0335] Next, at step 2404 , the SU modem selects an available AXCH and starts a fast transmit power ramp-up on the corresponding SAXPT. For a period the SU modem continues fast power ramp-up on SAXPT and the access modems continue to search for the SAXPT. At step 2405 , the RCS modem acquires the SAXPT of the SU and begins to search for the SU LAXPT. When the SAXPT is acquired, the modem informs the WAC controller, and the WAC controller sets the traffic lights corresponding to the modem to “red” to indicate the modem is now busy. The traffic lights are periodically output while continuing to attempt acquisition of the LAXPT.
[0336] The SU modem monitors, at step 2406 , the FBCH AXCH traffic light. When the AXCH traffic light is set to red, the SU assumes the RCS modem has acquired the SAXPT and begins transmitting LAXPT. The SU modem continues to ramp-up power of the LAXPT at a slower rate until sync-ind messages are received on the corresponding CTCH. If the SU is mistaken because the traffic light was actually set in response to another SU acquiring the AXCH, the SU modem times out because no sync-ind messages are received. The SU randomly waits a period of time, picks a new AXCH channel, and steps 2404 and 2405 are repeated until the SU modem receives sync-ind messages. Details of the power ramp up method used in the exemplary embodiment of this invention may be found in Section XXXXII hereinafter entitled “Method Of Controlling Initial Power Ramp-Up In CDMA Systems By Using Short Codes.”
[0337] Next, at step 2407 , the RCS modem acquires the LAXPT of the SU and begins sending sync-ind messages on the corresponding CTCH. The modem waits 10 msec for the pilot and AUX Vector correlator filters and phase-locked loop to settle, but continues to send sync-ind messages on the CTCH. The modem then begins looking for a request message for access to a bearer channel (MAC_ACC_REQ), from the SU modem.
[0338] The SU modem, at step 2408 , receives the sync-ind message and freezes the LAXPT transmit power level. The SU modem then begins sending repeated request messages for access to a bearer traffic channel (MAC_ACC_REQ) at fixed power levels, and listens for a request confirmation message (MAC_BEARER_CFM) from the RCS modem.
[0339] Next, at step 2409 , the RCS modem receives a MAC_ACC_REQ message; the modem then starts measuring the AXCH power level, and starts the APC channel. The RCS modem then sends the MAC_BEARER_CFM message to the SU and begins listening for the acknowledgment MAC_BEARER_CFM_ACK of the MAC_BEARER_CFM message. At step 2410 , the SU modem receives the MAC_BEARER_CFM message and begins obeying the APC power control messages. The SU stops sending the MAC_ACC_REQ message and sends the RCS modem the MAC_BEARER_CFM_ACK message. The SU begins sending the null data on the AXCH. The SU waits 10 msec for the uplink transmit power level to settle.
[0340] The RCS modem, at step 2411 , receives the MAC_BEARER_CFM_ACK message and stops sending the MAC_BEARER_CFM messages. APC power measurements continue.
[0341] Next, at step 2412 , both the SU and the RCS modems have synchronized the sub-epochs, obey APC messages, measure receive power levels, and compute and send APC messages. The SU waits 10 msec for downlink power level to settle.
[0342] Finally, at step 2413 , the bearer channel is established and initialized between the SU and RCS modems. The WAC receives the bearer establishment signal from the RCS modem, re-allocates the AXCH channel and sets the corresponding traffic light to green.
[0343] For the Outgoing Call Connection shown in FIG. 25 , the SU is placed in active mode by the off-hook signal at the user interface at step 2501 . Next, at step 2502 , the RCS indicates available AXCH channels by setting the respective traffic lights. At step 2503 , the SU synchronizes to the downlink pilot, waits for the SU modem vector correlator filters and phase lock loop to settle, and the SU checks service type and traffic lights for an available AXCH. Steps 2504 through 2513 are identical to the procedure steps 2404 through 2413 for the incoming call connection procedure of FIG. 24 , and therefore are not explained in detail.
[0344] In the previous procedures for incoming call connection and outgoing call connection, the power ramping-up process consists of the following events. The SU starts from very low transmit power and increases its power level while transmitting the short code SAXPT; once the RCS modem detects the short code it turns off the traffic light. Upon detecting the changed traffic light, the SU continues ramping-up at a slower rate this time sending the LAXPT. Once the RCS modem acquires the LAXPT and sends a message on CTCH to indicate this, the SU keeps its transmit (TX) power constant and sends the MAC-access-request message. This message is answered with a MAC_BEARER_CFM message on the CTCH. Once the SU receives the MAC_BEARER_CFM message it switches to the traffic channel (TRCH) which is the dial tone for POTS.
[0345] When the SU captures a specific user channel AXCH, the RCS assigns a code seed for the SU through the CTCH. The code seed is used by the spreading code generator in the SU modem to produce the assigned code for the reverse pilot of the SU, and the spreading codes for associated channels for traffic, call control, and signaling. The SU reverse pilot spreading code sequence is synchronized in phase to the RCS system global pilot spreading code, and the traffic, call control and signaling spreading codes are synchronized in phase to the SU reverse pilot spreading code.
[0346] If the SU is successful in capturing a specific user channel, the RCS establishes a terrestrial link with the remote processing unit to correspond to the specific user channel. For the DECT V5.1 standard, once the complete link from the RDU to the LE is established using the V5.1 ESTABLISHMENT message, a corresponding V5.1 ESTABLISHMENT ACK message is returned from the LE to the RDU, and the SU is sent a CONNECT message indicating that the transmission link is complete.
[0347] XXVIII. Support of Special Service Types
[0348] The system of the present invention includes a bearer channel modification feature which allows the transmission rate of the user information to be switched from a lower rate to a higher rate. The bearer channel modification (BCM) method is used to change a 32 kbs ADPCM channel to a 64 kbs PCM channel to support high speed data and fax communications through the spread-spectrum communication system of the present invention. Although the details of this technique are described in Section XXXXV hereinafter entitled “CDMA Communication System Which Selectively Suppresses Data Transmissioning During Establishment Of A Communication Channel”, the process is briefly described below:
[0349] First, a bearer channel on the RF interface is established between the RCS and SU, and a corresponding link exists between the RCS terrestrial interface and the remote processing unit, such as an RDU. The digital transmission rate of the link between the RCS and remote processing unit normally corresponds to a data encoded rate, which may be, for example, ADPCM at 32 kbs. The WAC controller of the RCS monitors the encoded digital data information of the link received by the line interface of the MUX. If the WAC controller detects the presence of the 2100 Hz tone in the digital data, the WAC instructs the SU through the assigned logical control channel and causes a second, 64 kbs duplex link to be established between the RCS modem and the SU. In addition, the WAC controller instructs the remote processing unit to establish a second 64 kbs duplex link between the remote processing unit and the RCS. Consequently, for a brief period, the remote processing unit and the SU exchange the same data over both the 32 kbs and the 64 kbs links through the RCS. Once the second link is established, the remote processing unit causes the WAC controller to switch transmission only to the 64 kbs link, and the WAC controller instructs the RCS modem and the SU to terminate and tear down the 32 kbs link. Concurrently, the 32 kbs terrestrial link is also terminated and torn down.
[0350] Another embodiment of the BCM method incorporates a negotiation between the external remote processing unit, such as the RDU, and the RCS to allow for redundant channels on the terrestrial interface, while only using one bearer channel on the RF interface. The method described is a synchronous switchover from the 32 kbs link to the 64 kbs link over the air link which takes advantage of the fact that the spreading code sequence timing is synchronized between the RCS modem and SU. When the WAC controller detects the presence of the 2100 Hz tone in the digital data, the WAC controller instructs the remote processing unit to establish a second 64 kbs duplex link between the remote processing unit and the RCS. The remote processing unit then sends 32 kbs encoded data and 64 kbs data concurrently to the RCS. Once the remote processing unit has established the 64 kbs link, the RCS is informed and the 32 kbs link is terminated and torn down. The RCS also informs the SU that the 32 kbs link is being torn down and to switch processing to receive unencoded 64 kbs data on the channel. The SU and RCS exchange control messages over the bearer control channel of the assigned channel group to identify and determine the particular subepoch of the bearer channel spreading code sequence within which the RCS will begin transmitting 64 kbit/sec data to the SU. Once the subepoch is identified, the switch occurs synchronously at the identified subepoch boundary. This synchronous switchover method is more economical of bandwidth since the system does not need to maintain capacity for a 64 kbs link in order to support a switchover.
[0351] In previously described embodiments of the BCM feature, the RCS will tear down the 32 kbs link first, but one skilled in the art would know that the RCS could tear down the 32 kbs link after the bearer channel has switched to the 64 kbs link.
[0352] As another special service type, the system of the present invention includes a method for conserving capacity over the RF interface for ISDN types of traffic. This conservation occurs while a known idle bit pattern is transmitted in the ISDN D-channel when no data information is being transmitted. The CDMA system of the present invention includes a method to prevent transmission of redundant information carried on the D-channel of ISDN networks for signals transmitted through a wireless communication link. The advantage of such method is that it reduces the amount of information transmitted and consequently the transmit power and channel capacity used by that information. The method is described as it is used in the RCS. In the first step, the controller, such as the WAC of the RCS or the SU controller of the SU, monitors the output D-channel from the subscriber line interface for a pre-determined channel idle pattern. A delay is included between the output of the line interface and the CDMA modem. Once the idle pattern is detected, the controller inhibits the transmission of the spread message channel through a message included in the control signal to the CDMA modem. The controller continues to monitor the output D-channel of the line interface until the presence of data information is detected. When data information is detected, the spread message channel is activated. Because the message channel is synchronized to the associated pilot which is not inhibited, the corresponding CDMA modem of the other end of the communication link does not have to reacquire synchronization to the message channel.
[0353] XXIX. Drop Out Recovery
[0354] The RCS and SU each monitor the CDMA bearer channel signal to evaluate the quality of the CDMA bearer channel connection. Link quality is evaluated using the SPRT process employing adaptive quantile estimation. The SPRT process uses measurements of the received signal power and, if the SPRT process detects that the local spreading code generator has lost synchronization with the received signal spreading code or if it detects the absence or low level of a received signal, the SPRT declares LOL.
[0355] When the LOL condition is declared, the receiver modem of each RCS and SU begins a Z-search of the input signal with the local spreading code generator. Z-search is well known in the art of CDMA spreading code acquisition and detection and is described in Digital Communications and Spread Spectrum Systems , by Robert E. Ziemer and Roger L. Peterson, at pages 492-94 which is incorporated herein by reference. The Z-search algorithm of the present invention tests groups of eight spreading code phases ahead and behind the last known phase in larger and larger spreading code phase increments.
[0356] During the LOL condition detected by the RCS, the RCS continues to transmit to the SU on the assigned channels, and continues to transmit power control signals to the SU to maintain SU transmit power level. The method of transmitting power control signals is described below. Successful reacquisition desirably takes place within a specified period of time. If reacquisition is successful, the call connection continues, otherwise the RCS tears down the call connection by deactivating and deallocating the RCS modem assigned by the WAC, and transmits a call termination signal to a remote call processor, such as the RDU, as described previously.
[0357] When the LOL condition is detected by the SU, the SU stops transmission to the RCS on the assigned channels which forces the RCS into a LOL condition, and starts the reacquisition algorithm. If reacquisition is successful, the call connection continues, and if not successful, the RCS tears down the call connection by deactivating and deallocating the SU modem as described previously.
[0358] XXX. Power Control
[0359] The power control feature of the present invention is used to minimize the amount of transmit power used by an RCS and the SUs of the system, and the power control subfeature that updates transmit power during bearer channel connection is defined as APC. APC data is transferred from the RCS to an SU on the forward APC channel and from an SU to the RCS on the reverse APC channel. When there is no active data link between the two, the maintenance power control (MPC) subfeature updates the SU transmit power.
[0360] Transmit power levels of forward and reverse assigned channels and reverse global channels are controlled by the APC algorithm to maintain sufficient signal power to interference noise power ratio (SIR) on those channels, and to stabilize and minimize system output power. The present invention uses a closed loop power control mechanism in which a receiver decides that the transmitter should incrementally raise or lower its transmit power. This decision is conveyed back to the respective transmitter via the power control signal on the APC channel. The receiver makes the decision to increase or decrease the transmitter's power based on two error signals. One error signal is an indication of the difference between the measured and desired despread signal powers, and the other error signal is an indication of the average received total power.
[0361] As used in the described embodiment of the invention, the term near-end power control is used to refer to adjusting the transmitter's output power in accordance with the APC signal received on the APC channel from the other end. This means the reverse power control for the SU and forward power control for the RCS; and the term far-end APC is used to refer to forward power control for the SU and reverse power control for the RCS (adjusting the opposite end's transmit power).
[0362] In order to conserve power, the SU modem terminates a transmission and powers-down while waiting for a call, defined as the sleep phase. Sleep phase is terminated by an awaken signal from the SU controller. The SU modem acquisition circuit automatically enters the reacquisition phase and begins the process of acquiring the downlink pilot, as described previously.
[0363] XXXI. Closed Loop Power Control Algorithms
[0364] The near-end power control consists of two steps: first, the initial transmit power is set; and second, the transmit power is continually adjusted according to information received from the far-end using APC.
[0365] For the SU, initial transmit power is set to a minimum value and then ramped up, for example, at a rate of 1 dB/ms until either a ramp-up timer expires (not shown) or the RCS changes the corresponding traffic light value on the FBCH to “red” indicating that the RCS has locked to the SU's short pilot SAXPT. Expiration of the timer causes the SAXPT transmission to be shut down, unless the traffic light value is set to red first, in which case the SU continues to ramp-up transmit power but at a much lower rate than before the “red” signal was detected.
[0366] For the RCS, initial transmit power is set at a fixed value, corresponding to the minimum value necessary for reliable operation as determined experimentally for the service type and the current number of system users. Global channels, such as global pilot or, FBCH, are always transmitted at the fixed initial power, whereas traffic channels are switched to APC.
[0367] The APC bits are transmitted as one bit up or down signals on the APC channel. In the described embodiment, the 64 kbs APC data stream is not encoded or interleaved. Far-end power control consists of the near-end transmitting power control information for the far-end to use in adjusting its transmit power. The APC algorithm causes the RCS or the SU to transmit +1 if the following inequality holds, otherwise −1.
[0000] α 1 e 1 −α 2 e 2 >0 Equation (45)
[0000] Here, the error signal e 1 is calculated as:
[0000] e 1 =P d −(1+SNR REQ ) P N Equation (46)
[0000] where P d is the despread signal plus noise power, P N is the despread noise power, and SNR REQ is the desired despread signal to noise ratio for the particular service type; and:
[0000] e 2 =P r −P o Equation (47)
[0000] where P r is a measure of the received power and P o is the AGC circuit set point. The weights α 1 and α 2 in Equation (45) are chosen for each service type and APC update rate.
[0368] XXXII. Maintenance Power Control
[0369] During the sleep phase of the SU, the interference noise power of the CDMA RF channel may change. The present invention includes a maintenance power control feature (MPC) which periodically adjusts the SU's initial transmit power with respect to the interference noise power of the CDMA channel. The MPC is the process whereby the transmit power level of an SU is maintained within close proximity of the minimum level for the RCS to detect the SU's signal. The MPC process compensates for low frequency changes in the required SU transmit power.
[0370] The maintenance control feature uses two global channels: one is called the status channel (STCH) on reverse link, and the other is called the check-up channel (CUCH) on forward link. The signals transmitted on these channels carry no data and they are generated the same way the short codes used in initial power ramp-up are generated. The STCH and CUCH codes are generated from a “reserved” branch of the global code generator.
[0371] The MPC process is as follows. At random intervals, the SU sends a symbol length spreading code periodically for 3 ms on the status channel (STCH). If the RCS detects the sequence, it replies by sending a symbol length code sequence within the next 3 ms on the check-up channel (CUCH). When the SU detects the response from the RCS, it reduces its transmit power by a particular step size. If the SU does not see any response from the RCS within that 3 ms period, it increases its transmit power by the step size. Using this method, the RCS response is transmitted at a power level that is enough to maintain a 0.99 detection probability at all SU's.
[0372] The rate of change of traffic load and the number of active users is related to the total interference noise power of the CDMA channel. The update rate and step size of the maintenance power update signal for the present invention is determined by using queuing theory methods well known in the art of communication theory, such as outlined in “ Fundamentals of Digital Switching ” (Plenum-New York) edited by McDonald and incorporated herein by reference. By modeling the call origination process as an exponential random variable with mean 6.0 mins, numerical computation shows the maintenance power level of a SU should be updated once every 10 seconds or less to be able to follow the changes in interference level using 0.5 dB step size. Modeling the call origination process as a Poisson random variable with exponential interarrival times, arrival rate of 2×10 −4 per second per user, service rate of 1/360 per second, and the total subscriber population is 600 in the RCS service area also yields by numerical computation that an update rate of once every 10 seconds is sufficient when 0.5 dB step size is used.
[0373] Maintenance power adjustment is performed periodically by the SU which changes from sleep phase to awake phase and performs the MPC process. Consequently, the process for the MPC feature is shown in FIG. 26 and is as follows: First, at step 2601 , signals are exchanged between the SU and the RCS maintaining a transmit power level that is close to the required level for detection: the SU periodically sends a symbol length spreading code in the STCH and the RCS periodically sends a symbol length spreading code in the CUCH as response.
[0374] Next, at step 2602 , if the SU receives a response within 3 ms after the STCH message it sent, it decreases its transmit power by a particular step size at step 2603 ; but if the SU does not receive a response within 3 ms after the STCH message, it increases its transmit power by the same step size at step 2604 .
[0375] The SU waits, at step 2605 , for a period of time before sending another STCH message, this time period is determined by a random process which averages 10 seconds. Thus, the transmit power of the STCH messages from the SU is adjusted based on the RCS response periodically, and the transmit power of the CUCH messages from the RCS is fixed (step 2606 ).
[0376] XXIII. Mapping of Power Control Signal to Logical Channels for APC
[0377] Power control signals are mapped to specified logical channels for controlling transmit power levels of forward and reverse assigned channels. Reverse global channels are also controlled by the APC algorithm to maintain sufficient signal power to interference noise power ratio (SIR) on those reverse channels, and to stabilize and minimize system output power. The present invention uses a closed loop power control method in which a receiver periodically decides to incrementally raise or lower the output power of the transmitter at the other end. The method also conveys that decision back to the respective transmitter.
[0000]
TABLE 13
APC Signal Channel Assignments
Link
Channels
Call/Connection
Power Control Method
and Signals
Status
Initial Value
Continuous
Reverse link
being established
as determined by
APC bits in forward
AXCH
power ramping
APC channel
AXPT
Reverse link
in-progress
level established
APC bits in forward
APC, OW,
during call set-up
APC channel
TRCH,
pilot signal
Forward link
in-progress
fixed value
APC bits in reverse
APC, OW,
APC channel
TRCH
[0378] Forward and reverse links are independently controlled. For a call/connection in process, forward link (TRCHs, APC, and OW) power is controlled by the APC bits transmitted on the reverse APC channel. During the call/connection establishment process, reverse link (AXCH) power is also controlled by the APC bits transmitted on the forward APC channel. Table 13 summarizes the specific power control methods for the controlled channels.
[0379] The required SIRs of the assigned channels TRCH, APC and OW and reverse assigned pilot signal for any particular SU are fixed in proportion to each other and these channels are subject to nearly identical fading, therefore, they are power controlled together.
[0380] XXXIV. AFPC
[0381] The AFPC process attempts to maintain the minimum required SIR on the forward channels during a call/connection. The AFPC recursive process, shown in FIG. 27 , consists of the steps of having an SU form the two error signals e 1 and e 2 in step 2701 where:
[0000] e 1 =P d −(1+SNR REQ ) P N Equation (48)
[0000] e 2 =P r −P o Equation (49)
[0000] and P d is the despread signal plus noise power, P N is the despread noise power, SNR REQ is the required signal to noise ratio for the service type, P r is a measure of the total received power, and P o is the AGC set point. Next, the SU modem forms the combined error signal α 1 e 1 +α 2 e 2 in step 2702 . Here, the weights α 1 and α 2 are chosen for each service type and APC update rate. In step 2703 , the SU hard limits the combined error signal and forms a single APC bit. The SU transmits the APC bit to the RCS in step 2704 and RCS modem receives the bit in step 2705 . The RCS increases or decreases its transmit power to the SU in step 2706 and the algorithm repeats starting from step 2701 .
[0382] XXXV. ARPC
[0383] The ARPC process maintains the minimum desired SIR on the reverse channels to minimize the total system reverse output power, during both call/connection establishment and while the call/connection is in progress. The recursive ARPC process, shown in FIG. 28 , begins at step 2801 where the RCS modem forms the two error signals e 1 and e 2 in step 2801 where:
[0000] e 1 =P d −(1+SNR REQ ) P N Equation (50)
[0000] e 2 =P rt −P o Equation (51)
[0000] and P d is the despread signal plus noise power, P N is the despread noise power, SNR REQ is the desired signal to noise ratio for the service type, P t is a measure of the average total power received by the RCS, and P o is the AGC set point. The RCS modem forms the combined error signal α 1 e 1 +α 2 e 2 in step 2802 and hard limits this error signal to determine a single APC bit in step 2803 . The RCS transmits the APC bit to the SU in step 2804 , and the bit is received by the SU in step 2805 . Finally, the SU adjusts its transmit power according to the received APC bit in step 2806 , and the algorithm repeats starting from step 2801 .
[0000]
TABLE 14
Symbols/Thresholds Used for APC Computation
Call/Connection
Symbol (and Threshold) Used for APC
Service or Call Type
Status
Decision
Don't care
being established
AXCH
ISDN D SU
in-progress
one 1/64-kbs symbol from TRCH (ISDN-D)
ISDN 1B + D SU
in-progress
TRCH (ISDN-B)
ISDN 2B + D SU
in-progress
TRCH (one ISDN-B)
POTS SU (64 KBPS PCM)
in-progress
one 1/64-KBPS symbol from TRCH, use 64 KBPS
PCM threshold
POTS SU (32 KBPS ADPCM)
in-progress
one 1/64-KBPS symbol from TRCH, use 32 KBPS
ADPCM threshold
Silent Maintenance Call (any
in-progress
OW (continuous during a maintenance call)
SU)
[0384] XXXVI. SIR and Multiple Channel Types
[0385] The required SIR for channels on a link is a function of channel format (e.g. TRCH, OW), service type (e.g. ISDN B, 32 KBPS ADPCM POTS), and the number of symbols over which data bits are distributed (e.g. two 64 kbs symbols are integrated to form a single 32 kbs ADPCM POTS symbol). Despreader output power corresponding to the required SIR for each channel and service type is predetermined. While a call/connection is in progress, several user CDMA logical channels are concurrently active; each of these channels transfers a symbol every symbol period. The SIR of the symbol from the nominally highest SIR channel is measured, compared to a threshold and used to determine the APC step up/down decision each symbol period. Table 14 indicates the symbol (and threshold) used for the APC computation by service and call type.
[0386] XXXVII. APC Parameters
[0387] APC information is always conveyed as a single bit of information, and the APC data rate is equivalent to the APC update rate. The APC update rate is 64 kbs. This rate is high enough to accommodate expected Rayleigh and Doppler fades and allow for a relatively high (−0.2) bit error rate (BER) in the uplink and downlink APC channels, which minimizes capacity devoted to the APC.
[0388] The power step up/down indicated by an APC bit is nominally between 0.1 and 0.01 dB. The dynamic range for power control is 70 dB on the reverse link and 12 dB on the forward link for the exemplary embodiment of the present system.
[0389] XXXVII. An Alternative Embodiment of Multiplexing of APC Information
[0390] The dedicated APC and OW logical channels described previously can also be multiplexed together in one logical channel. The APC information is transmitted at 64 kbs continuously whereas the OW information occurs in data bursts. The alternative multiplexed logical channel includes the unencoded, non-interleaved 64 kbs. APC information on, for example, the in-phase channel and the OW information on the quadrature channel of the QPSK signal.
[0391] XXXIX. Closed Loop Power Control Implementation
[0392] The closed loop power control during a call connection responds to two different variations in overall system power. First, the system responds to local behavior such as changes in power level of an SU, and second, the system responds to changes in the power level of the entire group of active users in the system.
[0393] The APS system of the exemplary embodiment of the present invention is shown in FIGS. 29A and 29B . As shown, the circuitry used to adjust the transmitted power is similar for the RCS (shown as the RCS power control module 2901 ) and SU (shown as the SU power control module 2902 ). Beginning with the RCS power control module 2901 , the reverse link RF channel signal is received at the RF antenna and demodulated to produce the reverse CDMA signal RMCH. The signal RMCH is applied to the variable gain amplifier (VGA 1 ) 2910 which produces an input signal to the AGC circuit 2911 . The AGC 2911 produces a variable gain amplifier control signal into the VGA 1 2910 . This signal maintains the level of the output signal of VGA 1 2910 at a near constant value. The output signal of VGA 1 is despread by the despread-demultiplexer (demux) 2912 , which produces a despread user message signal MS and a forward APC bit. The forward APC bit is applied to the integrator 2913 to produce the forward APC control signal. The forward APC control signal controls the forward link VGA 2 2914 and maintains the forward link RF channel signal at a minimum desired level for communication.
[0394] The signal power of the despread user message signal MS of the RCS power module 2901 is measured by the power measurement circuit 2915 to produce a signal power indication. The output of the VGA 1 is also despread by the AUX despreader 2981 which despreads the signal by using an uncorrelated spreading code, and hence obtains a despread noise signal. The power measurement by measure power 2982 of this signal is multiplied at multiplier 2983 by 1 plus the desired signal to noise ratio (SNR R ) to form the threshold signal S 1 . The difference between the despread signal power and the threshold value S 1 is produced by the subtracter 2916 . This difference is the error signal ES 1 , which is an error signal relating to the particular SU transmit power level. Similarly, the control signal for the VGA 1 2910 is applied to the rate scaling circuit 2917 to reduce the rate of the control signal for VGA 1 2910 . The output signal of scaling circuit 2917 is a scaled system power level signal SP 1 . The threshold compute logic 2918 calculates the system signal threshold value SST from the RCS user channel power data signal RCSUSR. The complement of the scaled system power level signal, SP 1 , and the system signal power threshold value SST are applied to the adder 2919 which produces the second error signal ES 2 . This error signal is related to the system transmit power level of all active SUs. The input error signals ES 1 and ES 2 are combined in the combiner 2920 to produce a combined error signal input to the delta modulator (DM 1 ) 2921 , and the output signal of the DM 1 is the reverse APC bit stream signal, having bits of value +1 or −1, which for the present invention is transmitted as a 64 kbs signal.
[0395] The reverse APC bit is applied to the spreading circuit 2922 , and the output signal of the spreading circuit 2922 is the spread-spectrum forward APC message signal. Forward OW and traffic signals are also provided to spreading circuits 2923 , 2924 , producing forward traffic message signals 1 , 2 , . . . N. The power level of the forward APC signal, the forward OW, and traffic message signals are adjusted by the respective amplifiers 2925 , 2926 and 2927 to produce the power level adjusted forward APC, OW and TRCH channels signals. These signals are combined by the adder 2928 and applied to the VGA 2 2914 , which produces forward link RF channel signal.
[0396] The forward link RF channel signal including the spread forward APC signal is received by the RF antenna of the SU, and demodulated to produce the forward CDMA signal FMCH. This signal is provided to the variable gain amplifier (VGA 3 ) 2940 . The output signal of VGA 3 is applied to the AGC 2941 which produces a variable gain amplifier control signal to VGA 3 2940 . This signal maintains the level of the output signal of VGA 3 at a near constant level. The output signal of VGA 3 2940 is despread by the despread demux 2942 , which produces a despread user message signal SUMS and a reverse APC bit. The reverse APC bit is applied to the integrator 2943 which produces the reverse APC control signal. This reverse APC control signal is provided to the reverse APC VGA 4 2944 to maintain the reverse link RF channel signal at a minimum power level.
[0397] The despread user message signal SUMS is also applied to the power measurement circuit 2945 producing a power measurement signal, which is added to the complement of threshold value S 2 in the adder 2946 to produce error signal ES 3 . The signal ES 3 is an error signal relating to the RCS transmit power level for the particular SU. To obtain threshold S 2 , the noise power of a despread signal produced by the AUX despreader 2985 , as measured by the power measurement circuit 2986 , is multiplied using multiplier 2987 by 1 plus the desired signal to noise ratio SNR R . The AUX despreader 2985 despreads the output signal of VGA 3 using an uncorrelated spreading code, hence its output is an indication of the despread noise power. Similarly, the control signal for the VGA 3 is applied to the rate scaling circuit 2970 to reduce the rate of the control signal for VGA 3 in order to produce a scaled received power level RP 1 . The threshold compute circuit 2998 computes the received signal threshold RST from the SU measured power signal SUUSR. The complement of the scaled received power level RP 1 and the received signal threshold RST are applied to the adder 2994 which produces error signal ES 4 . This error is related to the RCS transmit power to all other SUs. The input error signals ES 3 and ES 4 are combined in the combiner 2999 and input to the delta modulator DM 2 2947 . The output signal of DM 2 2947 is the forward APC bit stream signal, with bits having value of value +1 or −1. In the exemplary embodiment of the present invention, this signal is transmitted as a 64 kbs signal.
[0398] The forward APC bit stream signal is applied to the spreading circuit 2948 , to produce the output reverse spread-spectrum APC signal. Reverse OW and traffic signals are also input to spreading circuits 2949 , 2950 , producing reverse OW and traffic message signals 1 , 2 , . . . N, and the reverse pilot is generated by the reverse pilot generator 2951 . The power level of the reverse APC message signal, reverse OW message signal, reverse pilot, and the reverse traffic message signals are adjusted by amplifiers 2952 , 2953 , 2954 , 2955 to produce the signals which are combined by the adder 2956 and input to the reverse APC VGA 4 2944 . It is this VGA 4 2944 which produces the reverse link RF channel signal.
[0399] During the call connection and bearer channel establishment process, the closed loop power control of the present invention is modified, and is shown in FIGS. 30A and 30B . As shown, the circuits used to adjust the transmitted power are different for the RCS, shown as the initial RCS power control module 3001 ; and for the SU, shown as the initial SU power control module 3002 . Beginning with the initial RCS power control module 3001 , the reverse link RF channel signal is received at the RF antenna and demodulated producing the reverse CDMA signal IRMCH which is received by the first variable gain amplifier (VGA 1 ) 3003 . The output signal of VGA 1 is detected by the AGC circuit (AGC 1 ) 3004 which provides a variable gain amplifier control signal to VGA 1 3003 to maintain the level of the output signal of VGA 1 at a near constant value. The output signal of VGA 1 is despread by the despread demultiplexer 3005 , which produces a despread user message signal IMS. The forward APC control signal, ISET, is set to a fixed value, and is applied to the forward link variable gain amplifier (VGA 2 ) 3006 to set the forward link RF channel signal at a predetermined level.
[0400] The signal power of the despread user message signal IMS of the Initial RCS power module 3001 is measured by the power measure circuit 3007 , and the output power measurement is subtracted from a threshold value S 3 in the subtracter 3008 to produce error signal ES 5 , which is an error signal relating to the transmit power level of a particular SU. The threshold S 3 is calculated by multiplying using a multiplier 3083 the despread power measurement by measure power 3082 obtained from the AUX despreader 3081 by 1 plus the desired signal to noise ratio SNR R . The AUX despreader 3081 despreads the signal using an uncorrelated spreading code, hence its output signal is an indication of despread noise power. Similarly, the VGA 1 control signal is applied to the rate scaling circuit 3009 to reduce the rate of the VGA 1 control signal in order to produce a scaled system power level signal SP 2 . The threshold computation logic 3010 determines an initial system signal threshold value (ISST) computed from the user channel power data signal (IRCSUSR). The complement of the scaled system power level signal SP 2 and the ISST are provided to the adder 3011 which produces a second error signal ES 6 , which is an error signal relating to the system transmit power level of all active SUs. The value of ISST is the desired transmit power for a system having the particular configuration. The input error signals ES 5 and ES 6 are combined in the combiner 3012 to produce a combined error signal input to the delta modulator (DM 3 ) 3013 . DM 3 produces the initial reverse APC bit stream signal, having bits of value +1 or −1, which in the exemplary embodiment is transmitted as a 64 kbs signal.
[0401] The reverse APC bit stream signal is applied to the spreading circuit 3014 , to produce the initial spread-spectrum forward APC signal. The CTCH information is spread by the spreader 3016 to form the spread CTCH message signal. The spread APC and CTCH signals are scaled by the amplifiers 3015 and 3017 , and combined by the combiner 3018 . The combined signal is applied to VGA 2 3006 , which produces the forward link RF channel signal.
[0402] The forward link RF channel signal including the spread forward APC signal is received by the RF antenna of the SU and demodulated to produce the initial forward CDMA signal (IFMCH) which is applied to the variable gain amplifier (VGA 3 ) 3020 . The output signal of VGA 3 is detected by the AGC circuit (AGC 2 ) 3021 which produces a variable gain amplifier control signal for the VGA 3 3020 . This signal maintains the output power level of the VGA 3 3020 at a near constant value. The output signal of VGA 3 is despread by the despread demultiplexer 3022 , which produces an initial reverse APC bit that is dependent on the output level of VGA 3 . The reverse APC bit is processed by the integrator 3023 to produce the reverse APC control signal. The reverse APC control signal is provided to the reverse APC VGA 4 3024 to maintain the reverse link RF channel signal at a defined power level.
[0403] The global channel AXCH signal is spread by the spreading circuits 3025 to provide the spread AXCH channel signal. The reverse pilot generator 3026 provides a reverse pilot signal, and the signal power of AXCH and the reverse pilot signal are adjusted by the respective amplifiers 3027 and 3028 . The spread AXCH channel signal and the reverse pilot signal are summed by the adder 3029 to produce reverse link CDMA signal. The reverse link CDMA signal is received by the reverse APC VGA 4 3024 , which produces the reverse link RF channel signal output to the RF transmitter.
[0404] XXXX. System Capacity Management
[0405] The system capacity management algorithm of the present invention optimizes the maximum user capacity for an RCS area, called a cell. When the SU comes within a certain value of maximum transmit power, the SU sends an alarm message to the RCS. The RCS sets the traffic lights which control access to the system to “red” which, as previously described, is a flag that inhibits access by the SU's. This condition remains in effect until the call to the alarming SU terminates, or until the transmit power of the alarming SU, measured at the SU, is a value less than the maximum transmit power. When multiple SUs send alarm messages, the condition remains in effect until either all calls from alarming SUs terminate or until the transmit power of the alarming SU, measured at the SU, is less than the maximum transmit power. An alternative embodiment monitors the bit error rate measurements from the FEC decoder, and holds the RCS traffic lights at “red” until the bit error rate is less than a predetermined value.
[0406] The blocking strategy of the present invention includes a method which uses the power control information transmitted from the RCS to an SU, and the received power measurements at the RCS. The RCS measures its transmit power level, detects that a maximum value is reached and determines when to block new users. An SU preparing to enter the system blocks itself if the SU reaches the maximum transmit power before successful completion of a bearer channel assignment.
[0407] Each additional user in the system has the effect of increasing the noise level for all other users, which decreases the signal to noise ratio (SNR) that each user experiences. The power control algorithm maintains a desired SNR for each user. Therefore, in the absence of any other limitations, addition of a new user into the system has only a transient effect and the desired SNR is regained.
[0408] The transmit power measurement at the RCS is done by measuring either the root mean square (rms) value of the baseband combined signal or by measuring the transmit power of the RF signal and feeding it back to digital control circuits. The transmit power measurement may also be made by the SUs to determine if the unit has reached its maximum transmit power. The SU transmit power level is determined by measuring the control signal of the RF amplifier, and scaling the value based on the service type, such as POTS, FAX, or ISDN.
[0409] The information that an SU has reached the maximum power is transmitted to the RCS by the SU in a message on the assigned channels. The RCS also determines the condition by measuring reverse APC changes because, if the RCS sends APC messages to the SU to increase SU transmit power, and the SU transmit power measured at the RCS is not increased, the SU has reached the maximum transmit power.
[0410] The RCS does not use traffic lights to block new users who have finished ramping-up using the short codes. These users are blocked by denying them the dial tone and letting them time out. The RCS sends all 1's (go down commands) on the APC channel to make the SU lower its transmit power. The RCS also sends either no CTCH message or a message with an invalid address which would force the FSU to abandon the access procedure and start over. The SU, however, does not start the acquisition process immediately because the traffic lights are red.
[0411] When the RCS reaches its transmit power limit, it enforces blocking in the same manner as when an SU reaches its transmit power limit. The RCS turns off all the traffic lights on the FBCH, starts sending all 1 APC bits (go down commands) to those users who have completed their short code ramp-up but have not yet been given a dial tone, and either sends no CTCH message to these users or sends messages with invalid addresses to force them to abandon the access process.
[0412] The self blocking process of the SU is as follows. When the SU starts transmitting the AXCH, the APC starts its power control operation using the AXCH and the SU transmit power increases. While the transmit power is increasing under the control of the APC it is monitored by the SU controller. If the transmit power limit is reached, the SU abandons the access procedure and starts over.
[0413] XXXXI. System Synchronization
[0414] The RCS is synchronized either to the PSTN network clock signal through one of the line interfaces, as shown in FIG. 10 or to the RCS system clock oscillator, which free-runs to provide a master timing signal for the system. The global pilot channel, and therefore all logical channels within the CDMA channel, are synchronized to the system clock signal of the RCS. The global pilot (GLPT) is transmitted by the RCS and defines the timing at the RCS transmitter.
[0415] The SU receiver is synchronized to the GLPT, and so behaves as a slave to the network clock oscillator. However, the SU timing is retarded by the propagation delay. In the present embodiment of the invention, the SU modem extracts a 64 KHz and 8 KHz clock signal from the CDMA RF receive channel, and a PLL oscillator circuit creates 2 MHz and 4 MHz clock signals
[0416] The SU transmitter and hence the LAXPT or ASPT are slaved to the timing of the SU receiver. The RCS receiver is synchronized to the LAXPT or the ASPT transmitted by the SU, however, its timing may be retarded by the propagation delay. Hence, the timing of the RCS receiver is that of the RCS transmitter retarded by twice the propagation delay.
[0417] Furthermore, the system can be synchronized via a reference received from a GPS receiver. In a system of this type, a GPS receiver in each RCS provides a reference clock signal to all submodules of the RCS. Because each RCS receives the same time reference from the GPS, all of the system clock signals in all of the RCSs are synchronized.
[0418] The present invention also performs multichannel filtering. Details of this technique can be found in Section XXXXVI hereinafter entitled “Efficient Multichannel Filtering For CDMC Modems”.
[0419] XXXXII. A Method of Controlling Initial Power Ramp-Up in CDMA Systems by Using Short Codes
[0420] The use of the same frequency spectrum by a plurality of SUs increases the efficiency of a CDMA communication system. However, it also causes a gradual degradation of the performance of the system as the number of SUs increase. Each SU detects communication signals with its unique spreading code as valid signals and all other signals are viewed as noise. The stronger the signal from an SU arrives at the BS, the more interference the BS experiences when receiving and demodulating signals from other SUs. Ultimately, the power from one SU may be great enough to terminate communications of other SUs. Accordingly, it is extremely important in wireless CDMA communication systems to control the transmission power of all SUs. The control of transmission power is particularly critical when an SU is attempting to initiate communications with a BS and a power control loop has not yet been established. Typically, the transmission power required from an SU changes continuously as a function of the propagation loss, interference from other SUs, channel noise, fading and other channel characteristics. Therefore, an SU does not know the power level at which it should start transmitting. If the SU begins transmitting at a power level that is too high, it may interfere with the communications of other SUs and may even terminate the communications of other SUs. If the initial transmission power level is too low, the SU will not be detected by the BS and a communication link will not be established.
[0421] The present invention comprises a novel method of controlling transmission power during the establishment of a channel in a CDMA communication system by utilizing the transmission of a short code from an SU to a BS during initial power ramp-up. The short code is a sequence for detection by the BS which has a much shorter period than a conventional spreading code. The ramp-up starts from a power level that is guaranteed to be lower than the required power level for detection by the BS. The SU quickly increases transmission power while repeatedly transmitting the short code until the signal is detected by the BS. Once the BS detects the short code, it sends an indication to the SU to cease increasing transmission power. The use of short codes limits power overshoot and interference to other SUs and permits the BS to quickly synchronize to the spreading code used by the SU.
[0422] A communication network 3110 in one embodiment of the present invention is shown in FIG. 31 . The communication network 3110 generally comprises one or more BSs 3114 , each of which is in wireless communication with a plurality of SUs 3116 , which may be fixed or mobile. Each SU 3116 communicates with either the closest BS 3114 or the BS 3114 which provides the strongest communication signal. The BSs 3114 also communicate with a base station controller 3120 , which coordinates communications among BSs 3114 . The communication network 3110 may also be connected to a local exchange (LE) 3122 , wherein the base station controller 3120 also coordinates communications between the BSs 3114 and the LE 3122 . Preferably, each BS 3114 communicates with the base station controller 3120 over a wireless link, although a land line may also be provided. A land line is particularly applicable when a BS 3114 is in close proximity to the base station controller 3120 .
[0423] The base station controller 3120 performs several functions. Primarily, the base station controller 3120 provides all of the operations, administrative and maintenance (OA&M) signaling associated with establishing and maintaining all of the wireless communications between the SUs 3116 , the BSs 3114 and the base station controller 3120 . The base station controller 3120 also provides an interface between the wireless communication system 3110 and the LE 3122 . This interface includes multiplexing and demultiplexing of the communication signals that enter and leave the system 3110 via the base station controller 3120 . Although the wireless communication system 3110 is shown employing antennas to transmit RF signals, one skilled in the art should recognize that communications may be accomplished via microwave or satellite uplinks. Additionally, the functions of the base station controller 3120 may be combined with a BS 3114 to form a “master base station”.
[0424] Referring to FIG. 32 , the propagation of signals between a BS 3114 and a plurality of SUs 3116 is shown. A two-way communication channel (link) 3118 comprises a signal transmitted (Tx) 3126 from the BS 3114 to the SU 3116 and a signal received (Rx) 3128 by the BS 3114 from the SU 3116 . The Tx signal 3126 is transmitted from the BS 3114 and is received by the SU 3116 after a propagation delay Δt. Similarly, the Rx signal 3128 originates at the SU 3116 and terminates at the BS 3114 after a further propagation delay Δt. Accordingly, the round trip propagation delay is 2Δt. In the preferred embodiment, the BS 3114 has an operating range of approximately 30 kilometers. The round trip propagation delay 3124 associated with an SU 3116 at the maximum operating range is 200 microseconds.
[0425] It should be apparent to those of skill in the art that the establishment of a communication channel between a BS and an SU is a complex procedure as hereinbefore described involving many tasks performed by the BS and the SU which are outside the scope of the present invention. This aspect of present invention is directed to initial power ramp-up and synchronization during the establishment of a communication channel.
[0426] Referring to FIG. 33 , the signaling between a BS 3114 and an SU 3116 is shown. In accordance with the present invention, the BS 3114 continuously transmits a pilot code 3140 to all of the SUs 3116 located within the transmitting range of the BS 3114 . The SU 3116 must acquire the pilot code 3140 transmitted by the BS 3114 before it can receive or transmit any data. Acquisition is the process whereby the SU 3116 aligns its locally generated spreading code with the received pilot code 3140 . The SU 3116 searches through all of the possible phases of the received pilot code 3140 until it detects the correct phase, (the beginning of the pilot code 3140 ).
[0427] The SU 3116 then synchronizes its transmit spreading code to the received pilot code 3140 by aligning the beginning of its transmit spreading code to the beginning of the pilot code 3140 . One implication of this receive and transmit synchronization is that the SU 3116 introduces no additional delay as far as the phase of the spreading codes are concerned. Accordingly, as shown in FIG. 33 , the relative delay between the pilot code 3140 transmitted from the BS 3114 and the SU's transmit spreading code 3142 received at the BS 3114 is 2Δt, which is solely due to the round trip propagation delay.
[0428] In the preferred embodiment, the pilot code is 29,877,120 chips in length and takes approximately 2 to 5 seconds to transmit, depending on the spreading factor. The length of the pilot code 3140 was chosen to be a multiple of the data symbol no matter what kind of data rate or bandwidth is used. As is well known by those of skill in the art, a longer pilot code 3140 has better randomness properties and the frequency response of the pilot code 3140 is more uniform. Additionally, a longer pilot code 3140 provides low channel cross correlation, thus increasing the capacity of the system 3110 to support more SUs 3116 with less interference. The use of a long pilot code 3140 also supports a greater number of random short codes. For synchronization purposes, the pilot code 3140 is chosen to have the same period as all of the other spreading codes used by the system 3110 . Thus, once a SU 3116 acquires the pilot code 3140 , it is synchronized to all other signals transmitted from the BS 3114 .
[0429] During idle periods, when a call is not in progress or pending, the SU 3116 remains synchronized to the BS 3114 by periodically reacquiring the pilot code 3140 . This is necessary for the SU 3116 to receive and demodulate any downlink transmissions, in particular paging messages which indicate incoming calls.
[0430] When a communication link is desired, the BS 3114 must acquire the signal transmitted from the SU 3116 before it can demodulate the data. The SU 3116 must transmit an uplink signal for acquisition by the BS 3114 to begin establishing the two-way communication link. A critical parameter in this procedure is the transmission power level of the SU 3116 . A transmission power level that is too high can impair communications in the whole service area, whereas a transmission power level that is too low can prevent the BS 3114 from detecting the uplink signal.
[0431] The SU 3116 starts transmitting at a power level guaranteed to be lower than what is required and increases transmission power output until the correct power level is achieved. This avoids sudden introduction of a strong interference, hence improving system 3110 capacity.
[0432] The establishment of a communication channel in accordance with this embodiment of the present invention and the tasks performed by the BS 3114 and an SU 3116 are shown in FIG. 34 . Although many SUs 3116 may be located within the operating range of the BS 3114 , reference will be made hereinafter to a single SU 3116 for simplicity in explaining the operation of the present invention. Additionally, although the terminology “access code” is used herein as referring to the spreading code used with the “access signal”, access code and access signal may be used interchangeably. Finally, the terminology “confirmation signal” and “acknowledgement signal” may also be used interchangeably.
[0433] The BS 3114 begins by continuously transmitting a periodic pilot code 3140 to all SUs 3116 located within the operating range of the BS 3114 (step 3400 ). As the BS 3114 transmits the pilot code 3140 , the BS 3114 searches for an “access code” 3142 transmitted by an SU 3116 (step 3402 ). The access code 3142 is a known spreading code transmitted from an SU 3116 to the BS 3114 during initiation of communications and power ramp-up. The BS 3114 must search through all possible phases (time shifts) of the access code 3142 transmitted from the SU 3116 in order to find the correct phase. This is called the “acquisition” or the “detection” process. The longer the access code 3142 , the longer it takes for the BS 3114 to search through the phases and acquire the correct phase.
[0434] As previously explained, the relative delay between signals transmitted from the BS 3114 and return signals received at the BS 3114 corresponds to the round trip propagation delay 2Δt. The maximum delay occurs at the maximum operating range of the BS 3114 , known as the cell boundary. Accordingly, the BS 3114 must search up to as many code phases as there are in the maximum round trip propagation delay, which is typically less code phases than there are in a code period.
[0435] For a data rate Rb and spreading code rate Rc, the ratio L=Rc/Rb is called the spreading factor or the processing gain. In the preferred embodiment of the present invention, the cell boundary radius is 30 km, which corresponds to approximately between 1000 and 2500 code phases in the maximum round trip delay, depending on the processing gain.
[0436] If the BS 3114 has not detected the access code after searching through the code phases corresponding to the maximum round trip delay, the search is repeated starting from the phase of the pilot code 3140 which corresponds to zero delay (step 3404 ).
[0437] During idle periods, the pilot code 3140 from the BS 3114 is received at the subscriber unit 3116 which periodically synchronizes its transmit spreading code generator thereto (step 3406 ). If synchronization with the pilot code 3140 is lost, the SU 3116 reacquires the pilot code 3140 and resynchronizes (step 3408 ).
[0438] When it is desired to initiate a communication link, the SU 3116 starts transmitting the access code 3142 back to the BS 3114 (step 3410 ). The SU 3116 continuously increases the transmission power while retransmitting the access code 3142 (step 3412 ) until it receives an acknowledgment from the BS 3114 . The BS 3114 detects the access code 3142 at the correct phase once the minimum power level for reception has been achieved (step 3414 ). The BS 3114 subsequently transmits an access code detection acknowledgment signal (step 3416 ) to the SU 3116 . Upon receiving the acknowledgment, the SU ceases the transmission power increase (step 3418 ). With the power ramp-up completed, closed loop power control and call setup signaling is performed (step 3420 ) to establish the two-way communication link.
[0439] Although this embodiment limits SU 3116 transmission power, acquisition of the subscriber unit 3116 by the BS 3114 in this manner may lead to unnecessary power overshoot from the SU 3116 , thereby reducing the performance of the system 3110 .
[0440] The transmission power output profile of the SU 3116 is shown in FIG. 35 . At t 0 , the SU 3116 starts transmitting at the starting transmission power level P 0 , which is a power level guaranteed to be less than the power level required for detection by the BS 3114 . The SU 3116 continually increases the transmission power level until it receives the detection indication from the BS 3114 . For the BS 3114 to properly detect the access code 3142 from the SU 3116 the access code 3142 must: 1) be received at a sufficient power level; and 2) be detected at the proper phase. Accordingly, referring to FIG. 35 , although the access code 3142 is at a sufficient power level for detection by the BS 3114 at t P , the BS 3114 must continue searching for the correct phase of the access code 3142 which occurs at t A .
[0441] Since the SU 3116 continues to increase the output transmission power level until it receives the detection indication from the BS 3114 , the transmission power of the access code 3142 exceeds the power level required for detection by the BS 3114 . This causes unnecessary interference to all other SUs 3116 . If the power overshoot is too large, the interference to other SUs 3116 may be so severe as to terminate ongoing communications of other SUs 3116 .
[0442] The rate that the SU 3116 increases transmission power to avoid overshoot may be reduced, however, this results in a longer call setup time. Those of skill in the art would appreciate that adaptive ramp-up rates can also be used, yet these rates have shortcomings and will not appreciably eliminate power overshoot in all situations.
[0443] This embodiment of the present invention utilizes “short codes” and a two-stage communication link establishment procedure to achieve fast power ramp-up without large power overshoots. The spreading code transmitted by the SU 3116 is much shorter than the rest of the spreading codes (hence the term short code), so that the number of phases is limited and the BS 3114 can quickly search through the code. The short code used for this purpose carries no data.
[0444] The tasks performed by the BS 3114 and the SU 3116 to establish a communication channel using short codes in accordance with this embodiment of the present invention are shown in FIGS. 36A and 36B . During idle periods, the BS 3114 periodically and continuously transmits the pilot code to all SUs 3116 located within the operating range of the BS 3114 (step 3600 ). The BS 3114 also continuously searches for a short code transmitted by the SU 3116 (step 3602 ). The SU 3116 acquires the pilot code and synchronizes its transmit spreading code generator to the pilot code. The SU 3116 also periodically checks to ensure it is synchronized (step 3604 ). If synchronization is lost, the SU 3116 reacquires the pilot signal transmitted by the BS (step 3606 ).
[0445] When a communication link is desired, the SU 3116 starts transmitting a short code at the minimum power level P 0 (step 3608 ) and continuously increases the transmission power level while retransmitting the short code (step 3610 ) until it receives an acknowledgment from the BS 3114 that the short code has been detected by the BS 3114 .
[0446] The access code in the preferred embodiment, as previously described herein, is approximately 30 million chips in length. However, the short code is much smaller. The short code can be chosen to be any length that is sufficiently short to permit quick detection. There is an advantage in choosing a short code length such that it divides the access code period evenly. For the access code described herein, the short code is preferably chosen to be 32, 64 or 128 chips in length. Alternatively, the short code may be as short as one symbol length, as will be described in detail hereinafter.
[0447] Since the start of the short code and the start of the access code are synchronized, once the BS 3114 acquires the short code, the BS 3114 knows that the corresponding phase of the access code is an integer multiple of N chips from the phase of the short code where N is the length of the short code. Accordingly, the BS 3114 does not have to search all possible phases corresponding to the maximum round trip propagation delay.
[0448] Using the short code, the correct phase for detection by the BS 3114 occurs much more frequently. When the minimum power level for reception has been achieved, the short code is quickly detected (step 3612 ) and the transmission power overshoot is limited. The transmission power ramp-up rate may be significantly increased without concern for a large power overshoot. In the preferred embodiment of the present invention, the power ramp-up rate using the short code is 1 dB per millisecond.
[0449] The BS 3114 subsequently transmits a short code detection indication signal (step 3614 ) to the SU 3116 which enters the second stage of the power ramp-up upon receiving this indication. In this stage, the SU 3116 ceases transmitting the short code and starts continuously transmitting a periodic access code (step 3616 ). The SU 3116 continues to ramp-up its transmission power while transmitting the access code, however the ramp-up rate is now much lower than the previous ramp-up rate used with the short code (step 3618 ). The ramp-up rate with the access code is preferably 0.05 dB per millisecond. The slow ramp-up avoids losing synchronization with the BS 3114 due to small changes in channel propagation characteristics.
[0450] At this point, the BS 3114 has detected the short code at the proper phase and power level (step 3612 ). The BS 3114 must now synchronize to the access code which is the same length as all other spreading codes and much longer than the short code. Utilizing the short code, the BS 3114 is able to detect the proper phase of the access code much more quickly. The BS 3114 begins searching for the proper phase of the access code (step 3620 ). However, since the start of the access code is synchronized with the start of the short code, the BS 3114 is only required to search every N chips; where N=the length of the short code. In summary, the BS 3114 quickly acquires the access code of the proper phase and power level by: 1) detecting the short code; and 2) determining the proper phase of the access code by searching every N chips of the access code from the beginning of the short code.
[0451] If the proper phase of the access code has not been detected after searching the number of phases in the maximum round trip delay the BS 3114 restarts the search for the access code by searching every chip instead of every N chips (step 3622 ). When the proper phase of the access code has been detected (step 3624 ), the BS 3114 transmits an access code detection acknowledgment (step 3626 ) to the SU 3116 which ceases the transmission power increase (step 3628 ) upon receiving this acknowledgment. With the power ramp-up completed, closed loop power control and call setup signaling is performed (step 3630 ) to establish the two-way communication link.
[0452] Referring to FIG. 37 , although the starting power level P 0 is the same as in the prior embodiment, the SU 3116 may ramp-up the transmission power level at a much higher rate by using a short code. The short code is quickly detected after the transmission power level surpasses the minimum detection level, thus minimizing the amount of transmission power overshoot.
[0453] Although the same short code may be reused by the SU 3116 , in the preferred embodiment of the present invention the short codes are dynamically selected and updated in accordance with the following procedure. Referring to FIG. 38 , the period of the short code is equal to one symbol length and the start of each period is aligned with a symbol boundary. The short codes are generated from a regular length spreading code. A symbol length portion from the beginning of the spreading code is stored and used as the short code for the next 3 milliseconds. Every 3 milliseconds, a new symbol length portion of the spreading code replaces the old short code. Since the spreading code period is an integer multiple of 3 milliseconds, the same short codes are repeated once every period of the spreading code.
[0454] A block diagram of the BS 3114 is shown in FIG. 39 . Briefly described, the BS 3114 comprises a receiver section 3150 , a transmitter section 3152 and a diplexer 3154 . An RF receiver 3156 receives and down-converts the RF signal received from the diplexer 3154 . The receive spreading code generator 3158 outputs a spreading code to both the data receiver 3160 and the code detector 3162 . In the data receiver 3160 , the spreading code is correlated with the baseband signal to extract the data signal which is forwarded for further processing. The received baseband signal is also forwarded to the code detector 3162 which detects the access code or the short code from the SU 3116 and adjusts the timing of the spreading code generator 3158 to establish a communication channel 3118 .
[0455] In the transmitter section 3152 of the BS 3114 , the transmit spreading code generator 3164 outputs a spreading code to the data transmitter 3166 and the pilot code transmitter 3168 . The pilot code transmitter 3168 continuously transmits the periodic pilot code. The data transmitter 3166 transmits the short code detect indication and access code detect acknowledgment after the code detector 3162 has detected the short code or the access code respectively. The data transmitter also sends other message and data signals. The signals from the data transmitter 3166 and the pilot code transmitter 3168 are combined and up-converted by the RF transmitter 3170 for transmission to the SUs 3116 .
[0456] A block diagram of the SU 3116 is shown in FIG. 40 . Briefly described, the SU 3116 comprises a receiver section 3172 , a transmitter section 3174 and a diplexer 3184 . An RF receiver 3176 receives and down-converts the RF signal received from the diplexer 3184 . A pilot code detector 3180 correlates the spreading code with the baseband signal to acquire the pilot code transmitted by the BS 3114 . In this manner, the pilot code detector 3180 maintains synchronization with the pilot code. The receiver spreading code generator 3182 generates and outputs a spreading code to the data receiver 3178 and the pilot code detector 3180 . The data receiver 3178 correlates the spreading code with the baseband signal to process the short code detect indication and the access code detect acknowledgment transmitted by the BS 3114 .
[0457] The transmitter section 3174 comprises a spreading code generator 3186 which generates and outputs spreading codes to a data transmitter 3188 and a short code and access code transmitter 3190 . The short code and access code transmitter 3190 transmits these codes at different stages of the power ramp-up procedure as hereinbefore described. The signals output by the data transmitter 3188 and the short code and access code transmitter 3190 are combined and up-converted by the RF transmitter 3192 for transmission to the BS 3114 . The timing of the receiver spreading code generator 3182 is adjusted by the pilot code detector 3180 through the acquisition process. The receiver and transmitter spreading code generators 3182 , 3186 are also synchronized.
[0458] An overview of the ramp-up procedure in accordance with this embodiment of the invention is summarized in FIGS. 41A and 41B . The BS 3114 transmits a pilot code while searching for the short code (step 3200 ). The SU 3116 acquires the pilot code transmitted from the BS 3114 (step 3202 ), starts transmitting a short code starting at a minimum power level P 0 which is guaranteed to be less than the required power, and quickly increases transmission power (step 3204 ). Once the received power level at the BS 3114 reaches the minimum level needed for detection of the short code (step 3206 ) the BS 3114 acquires the correct phase of the short code, transmits an indication of this detection, and begins searching for the access code (step 3208 ). Upon receiving the detection indication, the SU 3116 ceases transmitting the short code and starts transmitting an access code. The SU 3116 initiates a slow ramp-up of transmit power while sending the access code (step 3210 ). The BS 3114 searches for the correct phase of the access code by searching only one phase out of each short code length portion of the access code (step 3212 ). If the BS 3114 searches the phases of the access code up to the maximum round trip delay and has not detected the correct phase, the search is repeated by searching every phase (step 3214 ). Upon detection of the correct phase of the access code by the BS 3114 , the BS 3114 sends an acknowledgment to the SU 3116 (step 3216 ). Reception of the acknowledgment by the SU 3116 concludes the ramp-up process. A closed loop power control is established, and the SU 3116 continues the call setup process by sending related call setup messages (step 3218 ).
[0459] XXXXIII. Virtual Locating of a Fixed SU To Reduce Re-Acquisition Time
[0460] A typical CDMA communication system is shown in FIG. 42 . The system comprises a BS and a plurality of fixed subscriber units SU 1 -SU 7 located at various distances from the BS. The BS constantly transmits a forward pilot signal. The SUs maintain epoch alignment between the forward pilot signal and their internal PN code generator such that all signals transmitted from an SU are at the same PN code phase at which the forward pilot is received. The BS receives signals from SUs with a code phase difference between its forward pilot signal and the received signal corresponding to the two-way signal propagation delay between the BS and the SU.
[0461] For the BS to detect a signal, it must align the phase of its receive PN code generator to the phase of the received signal, thus “acquiring” the signal. The BS can receive an access signal with any code phase difference within the range of the cell. Therefore, the BS must test all code phases associated with the range of possible propagation delays of the cell to acquire the access signal.
[0462] Once a communication channel is established between the BS and the SU, the transmission power of the SU is controlled by a closed loop APC algorithm which prevents the power from each SU from excessively interfering with other SUs. During channel establishment, before the closed loop power control begins, an SU's transmission power is kept to a minimum by ramping-up from a low level and establishing the channel without the SU significantly overshooting (on the order of less than 3 dB) the minimum power necessary to operate the channel.
[0463] To establish a channel, each SU transmits an access signal for detection by the BS. The BS acquires the access signal and transmits a confirmation signal to each SU. The time required for the BS to acquire the access signal contributes directly to the time elapsed between a SU going “off hook”, establishing a communication channel, connecting to the LE and receiving a dial tone. It is desirable to receive a dial tone within 150 msec of detection of “off hook”.
[0464] The time distribution of acquisition opportunities is shown in FIG. 43 for a typical prior art SU located 20 km from a BS in a 30 km cell. For a BS which tests 8 code phases simultaneously at a PN rate of 12.48 MHz and a symbol rate of 64,000 symbols per second and takes an average of 7.5 symbol periods to accept or reject a particular group of code phases, the average time to test all code phase delays within the cell is approximately 37 msec, and any one SU can only be detected during an approximately 100 μsec window during that period. Assuming that the selection of initial SU transmission power level is 15-20 dB below the proper level and a slow ramp-up rate of between 0.05 and 0.1 dB/msec, it could take 4-5 such 37 msec time periods, (or an average of approximately 200 msec,) for the BS to acquire a SU. This introduces an unacceptable delay in the channel establishment process which should be less than 150 msec. Accordingly, there is a need to reduce the amount of time required for a BS to acquire an SU.
[0465] The present invention includes a method of reducing the re-acquisition time of a fixed SU by a BS in a CDMA communication system by utilizing virtual locating of the SU. A BS acquires SUs by searching only those code phases concomitant with the largest propagation delay possible in the cell, as if all SUs were located at the periphery of the cell. An SU which has never been acquired by the BS varies the delay between the PN code phase of its received and transmitted signals over the range of possible delays in a cell and slowly ramps-up its transmission power until it is acquired by the BS. Upon initial acquisition by the BS the SU ceases ramping-up its power and varying the delay and internally stores the final value of the delay in memory. For subsequent re-acquisition, the SU adds the delay value between the PN code phase of its received and transmitted signals, making the subscriber virtually appear to be at the periphery of the cell. This permits a quick ramp-up of transmission power by the SU and reduced acquisition time by the BS.
[0466] Referring to FIG. 44 , the propagation of certain signals in the establishment of a communication channel 4018 between a BS 4014 and a plurality of SUs 4016 is shown. The forward pilot signal 4020 is transmitted from the BS 4014 at time t 0 , and is received by a SU 4016 after a propagation delay Δt. To be acquired by the BS 4014 the SU 4016 transmits an access signal 4022 which is received by the BS 4014 after a further propagation delay of Δt. Accordingly, the round trip propagation delay is 2Δt. The access signal 4022 is transmitted epoch aligned to the forward pilot signal 4020 , which means that the code phase of the access signal 4022 when transmitted is identical to the code phase of the received forward pilot signal 4020 .
[0467] The round trip propagation delay depends upon the location of an SU 4016 with respect to the BS 4014 . Communication signals transmitted between a SU 4016 located closer to the BS 4014 will experience a shorter propagation delay than an SU 4016 located further from the BS 4014 . Since the BS 4014 must be able to acquire SUs 4016 located at any position within the cell 4030 , the BS 4014 must search all code phases of the access signal corresponding to the entire range of propagation delays of the cell 4030 .
[0468] It should be apparent to those of skill in the art that the establishment of a communication channel between a BS 4014 and an SU 4016 is a complex procedure involving many tasks performed by the BS 4014 and the SU 4016 which are outside the scope of the present invention. The present invention is directed to decreasing the reacquisition time of a fixed SU 4016 by a BS 4014 during the re-establishment of a communication channel.
[0469] Referring to FIG. 45 , the tasks associated with initial acquisition of an SU 4016 by a BS 4014 in accordance with the preferred embodiment of the present invention are shown. When an SU 4016 desires the establishment of a channel 4018 with a BS 4014 with which it has never established a channel, the SU 4016 has no knowledge of the two-way propagation delay. Accordingly, the SU 4016 enters the initial acquisition channel establishment process.
[0470] The SU 4016 selects a low initial power level and zero code phase delay, (epoch aligning the code phase of the transmitted access signal 4022 to the code phase of the received forward pilot signal 4020 ), and commences transmitting the access signal 4022 while slowly (0.05-0.1 dB/msec) ramping-up transmission power (step 4100 ). While the SU 4016 is awaiting receipt of the acknowledgement signal from the BS 4014 , it varies the code phase delay in predetermined steps from zero to the delay corresponding to the periphery of the cell 4030 , (the maximum code phase delay), allowing sufficient time between steps for the BS 4014 to detect the access signal 4022 (step 4102 ). If the SU 4016 reaches the code phase delay corresponding to the periphery of the cell 4030 , it repeats the process of varying the code phase delay while continuing the slow power ramp-up (step 4102 ).
[0471] In order to acquire SUs 4016 desiring access, the BS 4014 continuously transmits a forward pilot signal 4020 and attempts to detect the access signals 4022 from SUs 4016 (step 4104 ). Rather than test for access signals 4022 at all code phase delays within the cell 4030 as with current systems, the BS 4014 need only test code phase delays centered about the periphery of the cell 4030 .
[0472] The BS 4014 detects the access signal 4022 (step 4106 ) when the SU 4016 begins transmitting with sufficient power at the code phase delay which makes the SU 4016 appear to be at the periphery of the cell 4030 , thereby “virtually” locating the SU 4016 at the periphery of the cell 4030 . The BS 4014 then transmits an acknowledgement to the SU 4016 which confirms that the access signal 4022 has been received (step 4108 ) and continues with the channel establishment process (step 4110 ).
[0473] Once the SU 4016 receives the acknowledgement signal (step 4112 ), it ceases the ramp-up of transmission power, ceases varying the code phase delay (step 4114 ) and records the value of the code phase delay for subsequent re-acquisitions (step 4116 ). The SU 4016 then continues the channel establishment process including closed-loop power transmission control (step 4118 ).
[0474] On subsequent re-acquisitions when an SU 4016 desires the establishment of a channel 4018 with a BS 4014 , the SU 4016 enters the re-acquisition channel establishment process shown in FIG. 46 . The SU 4016 selects a low initial power level and the code phase delay recorded during the initial acquisition process, (shown in FIG. 45 ), and commences continuously transmitting the access signal 4022 while quickly (1 dB/msec) ramping-up transmission power (step 4600 ). While the SU 4016 is awaiting receipt of the acknowledgement signal from the BS 4014 , it slightly varies the code phase delay of the access signal 4022 about the recorded code phase delay, allowing sufficient time for the BS 4014 to detect the access signal 4022 before changing the delay (step 4602 ). The BS 4014 as in FIG. 45 , transmits a forward pilot signal 4020 and tests only the code phase delays at the periphery of the cell 4030 in attempting to acquire the SUs 4016 within its operating range (step 4604 ). The BS 4014 detects the access signal 4022 when the SU 4016 transmits with sufficient power at the code phase delay which makes the SU 4016 appear to be at the periphery of the cell 4030 (step 4606 ). The BS 4014 transmits an acknowledgement to the SU 4016 which confirms that the access signal 4022 has been received (step 4608 ) and continues with the channel establishment process (step 4610 ).
[0475] When the SU 4016 receives the acknowledgement signal (step 4612 ), it ceases power ramp-up, ceases varying the code phase delay (step 4614 ) and records the present value of the code phase delay for subsequent re-acquisitions (step 4616 ). This code phase delay may be slightly different from the code phase delay initially used when starting the re-acquisitions process. The SU 4016 then continues the channel establishment process at the present power level (step 4618 ). If an SU 4016 has not received an acknowledgement signal from the BS 4014 after a predetermined time, the SU 4016 reverts to the initial acquisition process described in FIG. 45 .
[0476] The effect of introducing a code phase delay in the Tx 4020 and Rx 4022 communications between the BS 4014 and an SU 4016 will be explained with reference to FIGS. 47 and 48 . Referring to FIG. 47A , a BS 4160 communicates with two SUs 4162 , 4164 . The first SU 4162 is located 30 km from the BS 4160 at the maximum operating range. The second SU 4164 is located 15 km from the BS 4160 . The propagation delay of Tx and Rx communications between the first SU 4162 and the BS 4160 will be twice that of communications between the second SU 4164 and the BS 4160 .
[0477] Referring to FIG. 48 , after an added delay value 4166 is introduced into the Tx PN generator of the second SU 4164 the propagation delay of communications between the first SU 4162 and the BS 4160 will be the same as the propagation delay of communications between the second SU 4164 and the BS 4160 . Viewed from the BS 4160 , it appears as though the second SU 4164 is located at the virtual range 4164 ′.
[0478] Referring to FIG. 49 , it can be seen that when a plurality of SUs, SU 1 -SU 7 , are virtually relocated to the virtual range 4175 , the BS must only test the code phase delays centered about the virtual range 4175 .
[0479] Utilizing the present invention, an SU 4016 which has achieved a sufficient power level will be acquired by the BS 4014 in approximately 2 msec. Due to the shorter acquisition time, the SU 4016 can ramp-up at a much faster rate, (on the order of 1 dB/msec), without significantly overshooting the desired power level. Assuming the same 20 dB power back-off, it would take the SU 4016 approximately 20 msec to reach the sufficient power level for detection by the BS 4014 . Accordingly, the entire duration of the re-acquisition process of the present invention is approximately 22 msec, which is an order of magnitude reduction from prior art reacquisition methods.
[0480] An SU 4200 made in accordance with one embodiment of the present invention is shown in FIG. 50 . The SU 4200 includes a receiver section 4202 and a transmitter section 4204 . An antenna 4206 receives a signal from the BS 4014 , which is filtered by a band-pass filter 4208 having a bandwidth equal to twice the chip rate and a center frequency equal to the center frequency of the spread spectrum system's bandwidth. The output of the filter 4208 is down-converted by a mixer 4210 to a baseband signal using a constant frequency (Fc) local oscillator. The output of the mixer 4210 is then spread spectrum decoded by applying a PN sequence to a mixer 4212 within the PN Rx generator 4214 . The output of the mixer 4212 is applied to a low pass filter 4216 having a cutoff frequency at the data rate (Fb) of the PCM data sequence. The output of the filter 4216 is input to a codec 4218 which interfaces with the communicating entity 4220 .
[0481] A baseband signal from the communicating entity 4220 is pulse code modulated by the codec 4218 . Preferably, a 32 kilobit per second adaptive pulse code modulation (ADPCM) is used. The PCM signal is applied to a mixer 4222 within a PN Tx generator 4224 . The mixer 4222 multiplies the PCM data signal with the PN sequence. The output of the mixer 4222 is applied to low-pass filter 4226 whose cutoff frequency is equal to the system chip rate. The output of the filter 4226 is then applied to a mixer 4228 and suitably up-converted, as determined by the carrier frequency Fc applied to the other terminal. The up-converted signal is then passed through a band-pass filter 4230 and to a broadband RF amplifier 4232 which drives an antenna 4234 .
[0482] The microprocessor 4236 controls the acquisition process as well as the Rx and Tx PN generators 4214 , 4224 . The microprocessor 4236 controls the code phase delay added to the Rx and Tx PN generators 4214 , 4224 to acquire the forward pilot signal 4020 , and for the SU 4200 to be acquired by the BS 4014 , and records the code phase difference between these PN generators. For re-acquisition the microprocessor 4236 adds the recorded delay to the Tx PN generator 4224 .
[0483] The BS 4014 uses a configuration similar to the SU 4016 to detect PN coded signals from the SU 4200 . The microprocessor (not shown) in the BS 4014 controls the Rx PN generator in a similar manner to make the code phase difference between Rx PN generator and the Tx PN generator equivalent to the two-way propagation delay of the SU's 4016 virtual location. Once the BS 4014 acquires the access signal 4022 from the SU 4016 , all other signals from the SU 4016 to the BS 4014 (traffic, pilot, etc.) use the same code phase delay determined during the acquisition process.
[0484] It should be noted that although the invention has been described herein as the virtual locating of SUs 4016 at the periphery of the cell 4030 the virtual location can be at any fixed distance from the BS 4014 .
[0485] Referring to FIG. 51 , the tasks associated with initial acquisition of a “never-acquired” SU 4016 by a BS 4014 in accordance with an alternative embodiment of the present invention are shown. The SU 4016 continuously transmits an epoch aligned access signal 4022 to the BS 4014 (step 4300 ) when the establishment of a channel 4018 is desired. While the SU 4016 is awaiting the receipt of a confirmation signal from the BS 4014 , it continuously increases the transmission power as it continues transmission of the access signal 4022 (step 4302 ).
[0486] To detect SUs which have never been acquired, the BS 4014 transmits a forward pilot signal 4020 and sweeps the cell by searching all code phases corresponding to the entire range of propagation delays of the cell (step 4304 ) and detects the epoch aligned access signal 4022 sent from the SU 4016 after the transmission has achieved sufficient power for detection (step 4306 ). The BS 4014 transmits an acknowledgement to the SU 4016 (step 4308 ) which confirms that the access signal 4022 has been received. The SU 4016 receives the acknowledgment signal (step 4310 ) and ceases the increase in transmission power (step 4312 ).
[0487] The BS 4014 determines the desired code phase delay of the SU 4016 by noting the difference between the Tx and Rx PN generators 4224 , 4214 after acquiring the SU 4016 . The desired code phase delay value is sent to the SU 4016 (step 4316 ) as an OA&M message, which receives and stores the value (step 4318 ) for use during re-acquisition, and continues with the channel establishment process (steps 4322 and 4324 ).
[0488] Referring to FIG. 52 , an alternative method of fast reacquisition in accordance with the present invention is shown. When a communication channel must be reestablished between the SU 4016 and the BS 4014 , the SU 4016 transmits the access signal 4022 with the desired code phase delay as in the preferred embodiment.
[0489] With all of the previously acquired SUs 4016 at the same virtual range, the BS 4014 need only search the code phase delays centered about the periphery of the cell to acquire the access signals 4022 of such SUs 4016 (step 4330 ). Thus, an SU 4016 may ramp-up power rapidly to exploit the more frequent acquisition opportunities. The SU 4016 implements the delay the same way as in the preferred embodiment. The BS 4014 subsequently detects the SU 4016 at the periphery of the cell (step 4336 ), sends an acknowledgment signal to the SU (step 4337 ) and recalculates the desired code phase delay value, if necessary. Recalculation (step 4338 ) compensates for propagation path changes, oscillator drift and other communication variables. The BS 4014 sends the updated desired code phase delay value to the SU 4016 (step 4340 ) which receives and stores the updated value (step 4342 ). The SU 4016 and the BS 4014 then continue the channel establishment process communications (steps 4344 and 4346 ).
[0490] Note that this embodiment requires the BS to search both the code phase delays centered on the periphery of the cell to re-acquire previously acquired SUs and the code phase delays for the entire cell to acquired SUs which have never been acquired.
[0491] Referring to FIG. 53 , the tasks associated with initial acquisition of a never-acquired SU 4016 by a BS 4014 in accordance with a second alternative embodiment of the present invention are shown. In the embodiment shown in FIG. 51 , when a never-acquired SU 4016 is acquired, the access signal 4020 remains epoch aligned to the forward pilot signal 4020 . In this embodiment, the BS 4014 and SU 4016 change the code phase alignment of the access signal 4022 from epoch aligned to delayed, (by the code phase delay), to make the SU 4016 appear at the periphery of the cell. This change is performed at a designated time.
[0492] Steps 4400 through 4418 are the same as the corresponding steps 4300 through 4318 shown in FIG. 51 . However, after the BS 4014 sends the desired delay value to the SU 4016 (step 4416 ) the BS 4014 sends a message to the SU 4016 to switch to the desired delay value at a time referenced to a sub-epoch of the forward pilot signal 4020 (step 4420 ). The SU 4016 receives this message (step 4422 ), and both units 4014 , 4016 wait until the switchover time is reached (steps 4424 , 4430 ). At that time, the BS 4014 adds the desired delay value to its Rx PN operator (step 4432 ) and the SU 4016 adds the same desired delay value to its Tx PN generator (step 4426 ). The SU 4016 and the BS 4014 then continue the channel establishment process communication (step 4428 , 4434 ).
[0493] XXXXIV. Parallel Packetized Intermodule Arbitrated High Speed Control and Data Bus
[0494] For communication within a digital device, such as between a CPU (central processing unit), memory, peripherals, I/O (input/output) devices, or other data processors, a communication bus may be employed. As shown in FIG. 54 , a communication bus is a set of shared electrical conductors for the exchange of digital words. In this manner, communication between devices is simplified, thereby obviating separate interconnections.
[0495] A communication bus typically contains a set of data lines, address lines for determining which device should transmit or receive, and control and strobe lines that specify the type of command being executed. The address and strobe lines communicate one-way from the CPU. Typically, all data lines are bidirectional. Data lines are asserted by the CPU during the write instruction, and by the peripheral device during read. Both the CPU and peripheral device use three-state drivers for the data lines.
[0496] In a computer system where several data processing devices exchange data on a shared data bus, the two normal states of high and low voltage (representing the binary 1's and 0's) may be implemented by an active voltage pullup. However, when several processing modules are exchanging data on a data bus, a third output state, open circuit, must be added so that another device located on the bus can drive the same line.
[0497] Three-state or open-collector drivers are used so that devices connected to the bus can disable their bus drivers, since only one device is asserting data onto the bus at a given time. Each bus system has a defined protocol for determining which device asserts data. A bus system is designed so that, at most, one device has its drivers enabled at one time with all other devices disabled (third state). A device knows to assert data onto the bus by recognizing its own address on the control lines. The device looks at the control lines and asserts data when it sees its particular address on the address lines and a read pulse. However, there must be some external logic ensuring that the three-state devices sharing the same lines do not talk at the same time or bus contention will result.
[0498] Bus control logic or a “bus master” executes code for the protocol used to arbitrate control of the bus. The bus master may be part of a CPU or function independently. More importantly, control of the bus may be granted to another device. More complex bus systems permit other devices located on the bus to master the bus.
[0499] Data processing systems have processors which execute programmed instructions stored in a plurality of memory locations. As shown in FIG. 54 , the processed data is transferred in and out of the system onto the bus, by using I/O devices interconnecting with other digital devices. A bus protocol, or handshaking rules delineate a predetermined series of steps to permit data exchange between the devices.
[0500] To move data on a shared bus, the data, recipient and moment of transmission must be specified. Therefore, data, address and a strobe line must be specified. There are as many data lines as there are bits in a word to enable a whole word to be transferred simultaneously. Data transfer is synchronized by pulses on additional strobe bus lines. The number of address lines determines the number of addressable devices.
[0501] Communication buses are either synchronous or asynchronous. In a synchronous bus, data is asserted onto or retrieved from the bus synchronously with strobing signals generated by the CPU or elsewhere in the system. However, the device sending the data does not know if the data was received. In an asynchronous bus, although handshaking between communicating devices assures the sending device that the data was received, the hardware and signaling complexity is increased.
[0502] In most high-speed, computationally intensive multichannel data processing applications, digital data must be moved very rapidly to or from another processing device. The transfer of data is performed between memory and a peripheral device via the bus without program intervention. This is also known as direct memory access (DMA). In DMA transfers, the device requests access to the bus via special bus request lines and the bus master arbitrates how the data is moved, (either in bytes, blocks or packets), prior to releasing the bus to the CPU.
[0503] A number of different types of bus communication systems and protocols are currently in use today to perform data transfer. As shown in the table of FIG. 55 , various methods have been devised to manipulate data between processing devices. Data communication buses having powerful synchronous/high-level data link control SDLC/HDLC protocols exist, along with standardized parallel transmission such as small computer system interface (SCSI) and carrier-sense multiple-access/collision-detection (CSMA/CD) (Ethernet) networks. However, in specialized, high-speed applications, a simplified data communication bus is desired.
[0504] The present invention includes a parallel packetized intermodule arbitrated high speed control data bus system which allows high speed communications between microprocessor modules in a more complex digital processing environment. The system features a simplified hardware architecture featuring fast first-in/first-out (FIFO) queuing operating at 12.5 MHz, TTL CMOS compatible level clocking signals, single bus master arbitration, synchronous clocking, DMA, and unique module addressing for multiprocessor systems. The present invention includes a parallel data bus with sharing bus masters residing on each processing module decreeing the communication and data transfer protocols.
[0505] The high-speed intermodule communication bus (HSB) is used for communication between various microprocessor modules. The data bus is synchronous and completely bidirectional. Each processing module that communicates on the bus will have the described bus control architecture. The HSB comprises eight shared parallel data lines for the exchange of digital data and two additional lines for arbitration and clock signals. No explicit bus request or grant signals are required. The HSB can also be configured as a semi-redundant system, duplicating data lines while maintaining a single component level. The bus is driven by three-state gates with resistor pullups serving as terminators to minimize signal reflections.
[0506] To move data on the HSB, each processing module must specify the data, the recipient, and the moment when the data is valid. Only one message source, known as the bus master, is allowed to drive the bus at any given time. Since the data flow is bidirectional, the bus arbitration scheme establishes a protocol of rules to prevent collisions on the data lines when a given processing module microprocessor is executing instructions. The arbitration method depends on the detection of collisions present only on the arbitration bus and uses state machines on each data processing module to determine bus status. Additionally, the arbitration method is not daisy chained, allowing greater system flexibility.
[0507] The state machines located on each processing module are the controlling interface between the microprocessor used within a given processing module and the HSB. The circuitry required for the interface is comprised of a transmit FIFO, receive FIFO, miscellaneous directional/bidirectional signal buffers and the software code for the state machines executed in an erasable programmable logic device (EPLD).
[0508] The HSB 5020 of the present invention is shown in simplified form in FIG. 56 . The preferred embodiment comprises a bus controller 5022 , a transmit FIFO 5024 , a receive FIFO 5026 , an eight bit parallel data bus 5028 and a serial arbitration bus 5050 . The ends of the bus 5028 are terminated with a plurality of resistive dividers to minimize signal reflections. An internal 8 bit address and data bus 5030 couples the transmit 5024 and receive 5026 FIFOs and bus controller 5022 to a CPU 5032 and DMA controller 5033 located on a given processor module 5034 . The internal address and data bus 5030 also permits communication between the CPU 5032 and bus controller 5022 and various memory elements such as PROM 5036 , SRAM 5038 , and DRAM 5040 required to support the applications of the data processing module 5034 .
[0509] The HSB 5020 is a packetized message transfer bus system. Various processor modules 5034 can communicate data, control and status messages via the present invention.
[0510] The HSB 5020 provides high speed service for a plurality of processor modules 5034 with minimum delay. The message transfer time between modules is kept short along with the overhead of accessing the data bus 5028 and queuing each message. These requirements are achieved by using a moderately high clock rate and a parallel data bus 5028 architecture. Transmit 5024 and receive 5026 FIFOs are used to simplify and speed up the interface between a processor module 5034 CPU 5032 and the data bus 5028 .
[0511] Referring to FIGS. 57A-57E , a common clock signal (HSB_CLK) 5042 comprising a TTL compatible CMOS level signal with a frequency nominally 12.5 MHz and a duty cycle of approximately 50% synchronizes all HSB 5020 components and executions. The clock 5042 pulse may originate in any part of the complete digital system and its origination is beyond the scope of this disclosure.
[0512] The parallel data bus 5028 (HSB_DAT) lines 0 - 7 , provides 8 bidirectional TTL compatible CMOS level signals. Only one message source, the bus controller or master 5022 , is allowed to drive the bus 5028 at any one time. A bus arbitration scheme determines which out of a plurality of processing modules may become bus master and when.
[0513] The relationship of the data 5028 and control signal transitions to the clock 5042 edges are important to recovering the data reliably at a receiving module. Data is clocked out from a transmitting module 5034 onto the data bus 5028 with the negative or trailing edge of the clock signal 5042 . The data is then clocked on the positive or leading edge of the clock signal 5042 at an addressed receiving module. This feature provides a sufficient setup and hold time of approximately 40 ns without violating the minimum setup time for octal register 5060 .
[0514] Before data can be transmitted on the data bus 5028 , the bus controller 5022 must obtain permission from the arbitration bus 5050 to prevent a possible data collision. The message source must win an arbitration from a potential multiplicity of processor module 5034 access requests. The winner is granted temporary bus mastership for sending a single message. After the transfer of data is complete, bus mastership is relinquished, thereby permitting bus 5028 access by other processor modules 5034 .
[0515] No explicit bus request and grant signals are required with the serial arbitration method of the present invention. The preferred method eliminates complex signaling and signal lines, along with the requisite centralized priority encoder and usual granting mechanism. The arbitration method is not daisy chained so that any processor module location on the bus 5028 may be empty or occupied without requiring a change to address wiring.
[0516] In the present invention, the open-collector arbitration bus 5050 permits multiple processing modules 5034 to compete for control of the data bus 5028 . Since no processing module 5034 in the digital system knows a priori if another processing module has accessed the arbitration bus 5050 , modules within the HSB system may drive high and low level logic signals on the HSB simultaneously, causing arbitration collisions. The collisions occur without harm to the driving circuit elements. However, the collisions provide a method of determining bus activity.
[0517] The arbitration bus 5050 includes pullup resistors connected to a regulated voltage source to provide a logic 1 level. The arbitration bus driver 5052 connects the arbitration bus 5050 to ground to drive a logic 0 level. This results in a logic 1 only when no other processing module 5034 drives a logic 0. The arbitration bus 5050 will be low if any processing module 5034 arbitration bus 5050 driver 5052 asserts a logic 0.
[0518] As known to those familiar with the art, the connection is called “wired-OR” since it behaves like a large NOR gate with the line going low if any device drives high (DeMorgan's theorem). An active low receiver inverts a logic 0 level, producing an equivalent OR gate. Using positive-true logic conventions yields a “wired-AND,” using negative logic yields a “wired-OR.” This is used to indicate if at least one device is driving the arbitration bus 5050 and does not require additional logic. Therefore, if a processing module 5034 asserts a logic 1 on the arbitration bus 5050 and monitors a logic 0, via buffer 5053 on monitor line 5055 (BUS_ACT_N), the processing module 5034 bus controller 5022 determines that a collision has occurred and that it has lost the arbitration for access.
[0519] The arbitration method depends on the detection of collisions and uses state machines 5046 and 5048 within the bus controller 5022 on each processing module 5034 to determine arbitration bus 5050 status as arbitration proceeds. All transitions on the arbitration bus 5050 are synchronized to the bus clock 5042 . Each processor module 5034 has a unique programmed binary address to present to the arbitration bus 5050 . The device address in the current embodiment is six bits, thereby yielding 63 unique processing module 5034 identifications.
[0520] Each processing module 5034 bus controller 5022 located on the HSB 5020 monitors, (via a buffer 5053 ), and interrogates, (via a buffer 5052 ), the arbitration bus (HSBI_ARB 1 _N) 5050 . Six or more high level signals clocked indicate that the bus is not busy. If a processing module 5034 desires to send a message, it begins arbitration by serially shifting out its own unique six bit address onto the arbitration bus 5050 starting with the most significant bit. Collisions will occur on the arbitration bus 5050 bit by bit as each bit of the six bit address is shifted out and examined. The first detected collision drops the processing module 5034 wishing to gain access out of the arbitration. If the transmit state machine 5046 of the sending module 5034 detects a collision it will cease driving the arbitration bus 5050 , otherwise it proceeds to shift out the entire six bit address. Control of the data bus 5028 is achieved if the entire address shifts out successfully with no errors.
[0521] A priority scheme results since logic 0's pull the arbitration bus 5050 low. Therefore, a processor module 5034 serially shifting a string of logic 0's that constitute its address will not recognize a collision until a logic 1 is shifted. Addresses having leading zeroes effectively have priority when arbitrating for the bus 5050 . As long as bus 5028 traffic is not heavy, this effect will not be significant.
[0522] In an alternative embodiment, measures can be taken to add equity between processor modules 5034 if required. This can be done by altering module arbitration ID's or the waiting period between messages.
[0523] Once a processor module 5034 assumes bus mastership it is free to send data on the data bus 5028 . The bus controller 5022 enables its octal bus transceiver (driver) 5060 and transmits at the clock 5042 rate. The maximum allowed message length is 512 bytes. Typically, messages will be 256 bytes or shorter. After a successful arbitration, the arbitration bus 5050 is held low by the transmitting processor module 5034 during this period as an indication of a busy arbitration bus 5050 .
[0524] Once the data transfer is complete, the bus controller 5022 disables its octal bus transceiver (drivers) 5060 via line 5054 (HSB_A_EN_N) and releases the arbitration bus 5050 to high. Another arbitration anywhere in the system may then take place.
[0525] An alternative embodiment allows bus 5028 arbitration to take place simultaneous with data transfer improving on data throughput throughout the digital system. In the preferred embodiment, the delay is considered insignificant obviating the added complexity.
[0526] The bus controller 5022 is required to control the interface between the processing module 5034 microprocessor 5032 and the HSB 5020 and between the HSB and the bus (data bus 5028 and arbitration bus 5050 ) signals. In the preferred embodiment the bus controller 5022 is an Altera 7000 series erasable programmable logic device (EPLD). The 8 bit internal data bus 5030 interfaces the bus controller 5022 with the processor module 5034 CPU 5032 . The processor module 5034 CPU 5032 will read and write directly to the bus controller 5022 internal registers via the internal data bus 5030 . The bus controller 5022 monitors the arbitration bus 5050 for bus status. This is necessary to gain control for outgoing messages and to listen and recognize its address to receive incoming messages. The bus controller 5022 monitors and controls the data FIFO's 5024 and 5025 , DMA controller 5033 and bus buffer enable 5054 .
[0527] The components used in the preferred embodiment are shown in Table 15.
[0000]
TABLE 15
MANUFAC-
ELE-
QTY
TURER
PART NUMBER
DESCRIPTION
MENT
1
IDT
IDT7202LA-50J
1Kx9 Receive FIFO
5024
or
KM75C02AJ50
Samsung
1
IDT
IDT7204LA-50J
4Kx9 Transmit FIFO
5026
or
KM75C04AJ50
Samsung
1
TI
SN74ABT125
Quad tristate driver
5058
or
SN74BCT125
TI
3
TI
SN74ABT245
TTL Octal Buffers
5060
or
SN74BCT245
TI
1
Altera
7128E
erasable programmable
5022
logic device
[0528] Address decoding and DMA gating are required and are performed in the bus controller 5022 . The bus controller 5022 also contains a number of internal registers that can be read or written to. The CPU 5032 communicates with and instructs the bus controller 5022 over the 8 bit internal data bus 5030 .
[0529] Loading the transmit FIFO 5024 is handled by the bus controller 5028 , DMA and address decoding circuits contained within the bus controller 5022 . Gaining access to the bus 5028 and unloading the FIFO 5024 is handled by the transmit state machine.
[0530] On power up, the bus controller 5022 receives a hardware reset 56 . The application software running on the processor module 5034 CPU 5032 has the option of resetting the bus controller 5022 via a write strobe if the application requires a module reset. After a reset, the bus controller 5022 monitors the arbitration bus 5050 on line 5055 to determine bus activity and to sync with the data bus 5028 .
[0531] After a period of inactivity the bus controller 5022 knows that the bus 5028 is between messages and not busy. A processor module 5034 can then request control of the bus via arbitration. If no messages are to be sent, the bus controller 5022 continues to monitor the arbitration bus 5050 .
[0532] The processor module CPU 5032 writes messages into the transmit FIFO 5024 at approximately 20 Mbps. The DMA controller, a Motorola 68360 5033 running at 25 MHz will be able to DMA the transmit FIFO 5024 at approximately 12.5 Mbps. Since only one message is allowed in the transmit FIFO 5024 at any one time, the CPU 5032 must buffer additional transmit messages in its own RAM 5040 . Since the maximum allowable message length is 512 bytes with anticipated messages averaging 256 bytes, a FIFO length of 1 Kb is guaranteed not to overflow. Once a message has been successfully sent, the transmit FIFO 5024 flags empty and the next message can be loaded.
[0533] A typical 256 byte message sent by a processing module 5034 CPU 5032 at 12.5 MBps will take less than 21 μsec from RAM 5040 to transmit FIFO 5024 . Bus arbitration should occupy not more than 1 μsec if the bus is not busy. Total elapsed time from the loading of one transmit message to the next is approximately 43 to 64 μsec. Since not many messages can queue during this period, circular RAM buffers are not required.
[0534] As shown in FIGS. 58 and 60 , during DMA transfers, the DMA controller 5033 disables the processor module 5034 CPU 5032 and assumes control of the internal data bus 5030 . The DMA transfer is brought about by the processor module 5034 or by a request from another processor module 5134 . The other processor 5134 successfully arbitrates control of the data bus 5028 and signals the processor module CPU 5032 . The CPU 5032 gives permission and releases control of bus 5030 . The processor module CPU 5032 signals the DMA controller 5033 to initiate a data transfer. The DMA controller 5033 generates the necessary addresses and tracks the number of bytes moved and in what direction. A byte and address counter are a part of the DMA controller 5033 . Both are loaded from the processor module CPU 5032 to setup the desired DMA transfer. On command from the CPU 5032 , a DMA request is made and data is moved from RAM memory 5040 to the transmit FIFO 5024 .
[0535] A transfer on the bus 5028 is monitored by each processing module 5034 located on the bus 5028 . Each bus controller 5022 in the entire processor system contains the destination addresses of all devices on the bus 5028 . If a match is found, the input to that receiving processing module 5034 FIFO 5026 is enabled. Since multiple messages may be received by this FIFO 5026 , it must have more storage than a transmit FIFO 5024 . The receive FIFO 5026 has at a minimum 4 KB×9 of storage. This amount of storage will allow at least 16 messages to queue within the receive FIFO 5026 based on the message length of 256 bytes. A message burst from multiple sources could conceivably cause multiple messages to temporarily congest the receive FIFO 5026 . The receiving module CPU 5032 must have a suitable message throughput from the receive FIFO 5026 or else a data overflow will result in lost information. DMA is used to automatically transfer messages from the receive FIFO 5026 to RAM 5040 . The transfer time from the receive FIFO 5026 to RAM 5040 is typically 21 μsec.
[0536] When a message is received by the bus controller 5022 , a request for DMA service is made. Referring to FIG. 59 , the DMA controller 5033 generates a message received hardware interrupt (DMA DONE) and signals processor module CPU 5032 that it has control of the internal bus 5030 . An interrupt routine updates the message queue pointer and transfers the contents of receive FIFO 5026 to RAM memory 5040 . The DMA controller 5033 is then readied for the next message to be received and points to the next available message buffer. This continues until all of the contents of the receive FIFO 5026 are transferred. An end of message signal is sent by the receive FIFO 5026 to the DMA controller 5033 via the bus controller 5022 . The processor module 5034 CPU 5032 then regains control of the internal communication bus 5030 .
[0537] The total elapsed time that it takes for a source to destination message transfer is approximately 64 to 85 μsec. As shown in FIG. 60 , the time is computed from when a processor module 5034 starts to send a message, load its transmit FIFO 5024 , arbitrate and acquire the data bus 5028 , transfer the data to the destination receive FIFO 5126 , bus the message to the CPU 5132 and then finally transfer the message into RAM 5140 of the recipient module 5134 . The actual throughput is almost 200 times that of a 8 KBps time slot on a PCM highway.
[0538] Controlling the HSB 5020 requires two state machines; one transmitting information 5070 , the other receiving information 5072 . Both state machines are implemented in the bus controller 5022 as programmable logic in the form of Altera's MAX+PLUS II, Version 6.0 state machine syntax.
[0539] Any arbitrary state machine has a set of states and a set of transition rules for moving between those states at each clock edge. The transition rules depend both on the present state and on the particular combination of inputs present at the next clock edge. The Altera EPLD 5022 used in the preferred embodiment contains enough register bits to represent all possible states and enough inputs and logic gates to implement the transition rules.
[0540] A general transmit program flow diagram 5070 for the transmit state machine is shown in FIG. 61 . Within the general flow diagram 5070 are three state machine diagrams for the inquire 5074 , arbitrate 5076 and transmit 5078 phases of the transmit state machine.
[0541] The processor module CPU 5032 initiates the inquire phase 5074 . As shown in FIG. 62 , eight states are shown along with the transition rules necessary for the bus controller 5022 to sense bus activity. After initiation, a transmit request is forwarded to the bus controller 5022 to see if there is bus activity. The bus controller 5022 monitors the arbitration bus 5050 for a minimum of 7 clock cycles. Six internal bus controller addresses are examined for collisions. If no collisions are detected, a request to arbitrate is made on the inactive bus.
[0542] As shown in FIG. 63 , the arbitrate request sets a flip-flop 5080 and begins sending out a unique identifier followed by six address bits on the arbitration line (HSBI_ARB 1 _N) 5050 . A collision is detected if any of the bits transmitted are not the same as monitored. If the six bits are successfully shifted onto the bus 5028 , then that particular bus controller 5022 has bus mastership and seizes the bus. A transmit FIFO 5024 read enable is then set. If any one of the bits suffers a collision, the arbitration bus 5050 is busy and the processor module 5034 stops arbitrating.
[0543] Referencing FIG. 64 , the transmit FIFO 5024 read enable sets a flip-flop 5082 and initiates a transmit enable. The contents of transmit FIFO 5024 are output through the bus controller 5022 , through octal bus transceiver 5060 , onto the data bus 5028 . The data is transmitted until an end of message flag is encountered. Once the transmit FIFO 5024 is emptied, a clear transmit request signal is output, returning the bus controller 5022 back to monitoring the bus 5028 .
[0544] The state machine for controlling the receive FIFO 5026 is similarly reduced into two state machines. As shown in FIG. 65 , a general flow diagram is shown for controlling the receive FIFO 5026 .
[0545] Referencing FIG. 66 , the bus controller 5022 monitors the arbitration bus 5050 for a period lasting seven clock cycles. Bus activity is determined by the reception of a leading start bit from another processor module 5034 bus controller 5022 . If after seven clock cycles the bus has not been seized, a receive alert signal is input to receive flip-flop 5089 .
[0546] As shown in FIG. 67 , the bus controller 5022 examines the first bit of data transmitted and compares it with its own address. If the first data bit is the unique identifier for that bus controller 5022 , data is accumulated until an end of message flag is encountered. If the first data bit is not the unique identifier of the listening bus controller 5022 , the bus controller 5022 returns to the listening state.
[0547] There are two embodiments for the software to transmit messages. The first embodiment will allow waiting an average of 5050 μsec to send a message since there are no system interrupts performed. This simplifies queuing and unqueuing messages. The second embodiment assumes that messages are being sent fast, the operating system is fast and preemptive, system interrupts are handled quickly, and idling of the processor 5032 is not allowed while messaging.
[0548] Upon completion of the transmit DMA, data bus 5028 arbitration must take place. After the data bus 5028 has been successfully arbitrated, the bus controller 5022 may release the transmit FIFO 5024 thereby placing the contents on the data bus 5028 . An empty flag signals a complete transfer to the bus controller 5022 and processor module 5034 CPU 5032 .
[0549] XXXXV. CDMA Communication System which Selectively Suppresses Data Transmissions During Establishment of a Communication Channel
[0550] One of the problems associated with wireless communication of data is that many different types of communicating nodes are currently in use including computers, facsimile machines, automatic calling and answering equipment and other types of data networks. These nodes may be able to communicate at a plurality of different data rates and must be properly synchronized to avoid losing data during the establishment or maintenance of a communication.
[0551] The present invention includes a feature which prevents the transmission of data between communicating nodes until the data communication rate required by the communicating nodes has been completely established throughout the system. The system selectively suppresses the confirmation tone that a receiving node sends to an originating node. Accordingly, the transmission of voice, facsimile or modem data is prevented until the communication path has been established at the desired communication rate. This permits the system to reliably transport encoded data at a plurality of data rates across a telecommunication system which may lack precise synchronization.
[0552] Referring to FIG. 68 , the communication system 6010 is generally connected to originating nodes 6040 and terminating nodes 6044 . In order to conserve as much bandwidth as possible, the communication system 6010 selectively allots the bandwidth required for supporting the data transmission rate required by the originating and terminating nodes 6040 , 6044 . In this manner, the system 6010 ensures that the bandwidth is utilized efficiently. Voiced communications may be effectively transmitted across a 32 Kbs ADPCM channel. However, a high speed fax or data modem signal requires at least a 64 Kbs pulse code modulation (PCM) signal to reliably transmit the communication. Many other types of modulation techniques and data transmission rates may also be utilized by originating and terminating nodes 6040 , 6044 . The system 6010 must be able to effectively allocate bandwidth and dynamically switch between these data communication rates and modulation schemes on demand.
[0553] The communication system 6010 provides a communication link between the originating and terminating nodes 6040 , 6044 . The originating and terminating nodes 6040 , 6044 may comprise computers, facsimile machines, automatic calling and answering equipment, data networks or any combination of this equipment. For robust communication of data it is imperative to ensure that the communication system 6010 switches to the data transmission rate required by the communicating nodes 6040 , 6044 prior to the transmission of any data.
[0554] Referring to FIG. 69 , the typical procedure for establishing communications between originating nodes 6040 and terminating nodes is shown. The originating node 6040 periodically transmits a calling tone (step 6100 ) which indicates that a data communication, (not a voice communication), is to be transmitted. The calling tone which is sent from the originating node 6040 to the terminating node 6044 is detected by the terminating node 6044 (step 6102 ) which initiates several actions. First, the terminating node 6044 prepares to send a data communication (step 6104 ). Next, the terminating node 6044 transmits an answering tone (step 6106 ) to the originating node 6040 to confirm that the terminating node 6044 has received the calling tone. Upon receipt of the answering tone (step 6108 ), the originating node 6040 begins the transmission of data (step 6110 ), which is received by the terminating node 6044 (step 6112 ). With the communication link established at the data transmission rate, the originating and terminating 6040 , 6044 nodes transmit and receive data until termination of the communication.
[0555] One problem with this process is that the transmission rate of the communication system 6010 is transparent to both the communicating and terminating nodes 6040 , 6044 . Modification of the transmission rate from a low rate that supports voice communication to a high rate that supports encoded data communication ensures that data will be reliably and quickly transmitted over a communication channel. However, the new transmission rate must be completely established throughout the communication system 6010 to prevent false interpretation of tones transmitted by the originating node 6040 . The originating node 6040 may begin transmission of data at a high rate before the system 6010 has fully switched from 32 Kbs ADPCM to 64 Kbs PCM resulting in loss of data.
[0556] In order to obviate tone misinterpretation and to prevent the resulting erroneous operation of the originating or transmitting nodes 6040 , 6044 , the present invention blocks the transmission of the confirming tone to the originating node 6040 until the new data transmission rate has been completely established throughout the communication system 6010 . This prevents the reception of the answering tone at the transmitting node 6040 and ensures the reliable transportation of encoded data at a higher rate across a communication system 6010 which lacks the precise synchronization which would otherwise be required.
[0557] The operation of the system 6010 of the present invention will be explained with reference to FIG. 70 . The communication system 6010 facilitates communications between an originating node 6040 and a terminating node 6044 . As shown, the actions of the originating node 6040 (steps 6202 , 6212 and 6214 ) and the actions of the terminating node 6044 (steps 6206 , 6207 , 6208 and 6218 ) are the same as in FIG. 69 . The operation of the communication system 6010 is transparent to both the originating node 6040 and the terminating node 6044 .
[0558] In operation, the originating node 6040 periodically transmits a calling tone (step 6202 ) which indicates a data communication. The communication system 6010 performs several actions in response to receipt of the calling tone (step 6204 ). First, the calling tone is received at 32 Kbs ADPCM which is the standard communication setting for voice communications. The system 6010 detects the calling tone and initiates a switch to 64 Kbs PCM in order to handle the high-speed data transmission. This switch must be implemented by the BS 6014 , the SU 6016 and the controller 6020 . Although the system 6010 immediately begins the switching over to the new data transmission rate, the process takes approximately 1500 msec to implement. Accordingly, the system 6010 transmits the calling tone to the terminating node 6044 at 32 Kbs ADPCM.
[0559] The terminating node 6044 detects the calling tone (step 6206 ) and prepares to send a data communication (step 6207 ). The terminating node 6044 subsequently transmits the answering tone (step 6208 ) which, when received by the originating node, will cause the originating node 6040 to begin transmission of data.
[0560] The communication system 6010 receives the answering tone from the terminating node 6044 . However, the system 6010 does not forward the answering tone to the originating node 6040 until the switch to 64 Kbs PCM has been established throughout the system 6010 . After the system 6010 has confirmed that the switch to 64 Kbs PCM has been achieved, it permits the answering tone to pass through to the originating node 6040 , which receives the tone (step 6212 ). In response to the answering tone, the originating node 6040 begins transmission of data (step 6214 ). The system 6010 receives the data and begins transmission of data at the new data transmission rate of 64 kbs PCM (step 6216 ) to the terminating node 6044 which receives the data (step 6218 ). Since the communication channel has been established, the originating and terminating nodes 6040 , 6044 continue to communicate over the system 6010 in this manner (steps 6214 , 6216 and 6218 ) until the communication is terminated.
[0561] Referring to FIG. 71 , a more detailed block diagram of the controller 6020 is shown. The controller 6020 controls at least a portion of the communication link between two communicating nodes 6040 , 6044 . This link comprises the transmission path 6300 from a first communicating node to the controller 6020 , the transmission path 6302 within the controller 6020 , and the transmission path 6304 from the controller 6020 to the second communicating node. The transmission paths 6300 , 6304 to and from the controller 6020 may include a plurality of BSs 6014 and SUs 6016 which are controlled by the controller 6020 .
[0562] It should be appreciated by those of skill in the art that the establishment of a communication channel between communicating nodes 6040 , 6044 is a complex procedure involving a plurality of tasks performed by the BS 6014 , the SU 6016 and the controller 6020 . A detailed description of the entire procedure is outside the scope of the present invention. Accordingly, only those portions of the procedure for establishment of a communication channel relevant to the present invention will be described hereinafter.
[0563] The communications between an originating node 6040 and a terminating node 6044 are transmitted over a virtual channel as is well known by those of skill in the art. Since the entire spectrum is used by the CDMA communication system 6010 , communications from the originating node 6040 to the terminating node 6044 are transmitted over the same frequency band as communications from the terminating node 6044 to the originating node 6040 . After the virtual channel has been established, the originating and terminating nodes 6040 , 6044 may freely communicate.
[0564] The controller 6020 includes a calling tone detector 6310 , a microprocessor 6312 and an answering tone blocker 6314 . The calling tone detector 6310 monitors the communication channel which has been established in order to detect the calling tone. When a calling tone is transmitted from an originating node 6040 , the calling tone detector 6310 detects the calling tone, which causes the controller 6020 to initiate the switch to a higher data transmission rate. The microprocessor 6312 subsequently informs any other BSs 6014 or SUs 6016 through which the communication is to be routed (hereinafter called communicating equipment) to initiate the switch to the higher data transmission rate.
[0565] The microprocessor 6312 activates the answering tone blocker 6314 which will prevent the answering tone from being transmitted through the system 6010 . Each piece of communicating equipment 6014 , 6016 , 6020 transmits an acknowledgment to the microprocessor 6312 of the controller 6020 when the higher data transmission rate has been achieved. The microprocessor 6312 subsequently deactivates the answering tone blocker 6314 which permits the answering tone to be forwarded to the originating node 6040 . The communicating nodes 6040 , 6044 commence data transmission over the communication system 6010 at the higher data transmission rate.
[0566] Although the invention has been described in part by making detailed reference to the preferred embodiment, such detail is intended to be instructive rather than restrictive. For example, the functions performed by the controller 6020 shown in FIG. 71 may, in an alternative embodiment, be performed by a BS 6014 coupled with either the originating or terminating nodes 6040 , 6044 . The functions of a BS 6014 may also be combined with the controller 6020 , to form a master base station. Additionally, different data rates and modulation schemes may be employed.
[0567] XXXXVI. Efficient Multichannel Filtering for CDMA Modems
[0568] Each communication channel within a CDMA communication system typically uses DSP (digital signal processing) hardware and software to filter, weight, and combine each signal prior to transmission. The weighting, filtering and combining of multiple signal channels is performed in the transmit circuitry of a CDMA communication system BS.
[0569] Prior art CDMA modems require many multipliers and binary adders for channel weighting and combining. The filter operation used is equivalent to that of a FIR (finite impulse response or transversal) structure. Each individual FIR filter used also requires many multipliers and adders.
[0570] A multiplier implemented in digital form is inefficient and expensive. The expense is directly related to logic gate count. Binary adders are less costly than binary multipliers, however, their use should be minimized. To implement a design using binary multiplication and addition into an ASIC (application specific integrated circuit) would be expensive to manufacture and would result in a more inefficient and slower signal throughput.
[0571] The disadvantage with prior art CDMA modems is the ability to weight, filter, and combine a plurality of single bit valued signal channels efficiently and accurately. When a multiplicity of signal processing channels are involved, the consistency between channels becomes important and the cost of hardware per channel escalates. In a CDMA communication system, it is necessary to use the minimum amount of power to achieve the minimum required bit error rate (BER) for maximum user capacity.
[0572] Each channel must have appropriate individual weights applied so that the same relative amplitudes are transmitted. After the weighting operation, each data stream is represented by multibit values. These are typically summed together in a large digital summing circuit that consists of a tree of numerous two input adders. The weighted and summed digital values are then filtered in a conventional FIR filter. The multipliers in the FIR process the multibit data and weighting coefficients to the desired precision. A multichannel filter for a CDMA modem constructed according to the teachings of the prior art would require separate FIR integrated circuits rather than total integration onto an economical ASIC (application specific integrated circuit).
[0573] The efficient, multichannel filter for CDMA modems of the present invention allows multiple channels consisting of serial, digital bit streams to be filtered by digital signal processing techniques performing sample weighting and summing functions. Each individual channel may have custom weighting coefficients or weighting coefficients common for all channels. If the weighting coefficients are by adaption, the same approach may be taken.
[0574] The multichannel FIR filter presented is implemented with no multipliers and a reduction in the number of adders. To increase the speed of operation, the filter structure utilizes look-up tables (LUTs) storing the weighting coefficients. The invention can be constructed either as a FPGA (field programmable gate array) or an ASIC. The use of LUTs save significant chip resources and manufacturing costs.
[0575] The multichannel FIR filter for CDMA modems in accordance with one aspect of the present invention is described with reference to the drawing figures where like numerals represent like elements throughout. Such modems are used in multichannel wireless communication stations in conjunction with the transmission and reception of communication signals.
[0576] By way of background, many systems have the property of having their outputs at a given instant of time depend not only on the input at the time, but on the entire, or immediate history of the input. Such systems are said to have memory, averaging past and present samples in arriving at an output. It is necessary to separate systems with memory into the classes of discrete and continuous systems. A discrete system is one whose inputs and outputs are sequences of numerical values rather than continuous functions of time.
[0577] A sequence of discrete values can be represented as x k , where the value x is a quantity such as voltage. The subscript k represents the sequence number. Very often in digital signal processing, x k represents a sampled waveform or signal where the subscript specifies the point in time at which the sample was taken. However, the subscript can represent an alternative meaning such as distance in a spatially sampled application. For a system to be physically realizable, the output must depend only on the present and past history of the input. No real system can have an output that depends on the future of the input. The dependence of the output of any physically realizable system on the input is indicated by:
[0000] y k =ƒ( x k , x k−1 , x k−2 , . . . , x k−n ) Equation (52)
[0000] where the input variables are x k , the output variable is y k , and ƒ(*) is any arbitrary function of n+1 variables. Although this function is too broadly defined to be analyzed in general, the subset of linear operations becomes very useful for a plurality of signal processing applications. These functions also prove to be much more tractable in analysis.
[0578] If the output depends on the previous n samples of the input (a system having a finite memory) in a linear fashion, Equation (52) can be written as:
[0000]
y
k
=
∑
j
=
0
N
a
j
x
k
-
j
+
b
Equation
(
53
)
[0579] Such a linear system is characterized by the N+1 weighting variables a j , and by the bias b. An unbiased, discrete linear system is characterized by the weighting variables (a 0 , a 1 , . . . , a n ). If the input x k is a delta function (unity for one sample and zero for all others), it can be seen that the output of Equation (53) is the sequence of weighting variables a 0 , a 1 , . . . , a n . Therefore, the response to the input completely characterizes an unbiased, linear system.
[0580] There are certain types of linear systems with memory that can be analyzed using linear techniques. Even though digital signal processing is discrete by nature, if the input is samples of a continuous input and is sampled sufficiently fast, it is possible to simulate a continuous system using the samples as the input variables. The output then appears as a linear system with a long memory. One such system is a FIR filter 7020 . A fixed coefficient FIR filter is characterized by the input/output Equation (54) as follows:
[0000]
y
k
=
∑
j
=
0
N
-
1
c
i
x
k
-
j
Equation
(
54
)
[0000] as shown in FIG. 72 , or expanded as
[0000] y k =c 0 x k +c 1 x k−1 + . . . +c k−1 x k−(N−1) Equation (55)
[0000] where the FIR filter has an impulse response c 0 , c 1 , . . . x k represents the discrete input signal samples at time k; c i are the filter coefficient weights; N are the number of taps; and y k represents the output at time k. As shown in FIG. 72 , the block diagram forms a tapped delay line with the coefficients being known as tap weights.
[0581] Digital filters are presently a common requirement for digital signal processing systems. In the field of discrete systems, the most popular type of digital filter using convolution is the FIR. FIR filters have two advantages. The first is that FIR filters are inherently stable. The finite length of the impulse response guarantees that the output will go to zero within N samples. The second advantage is that FIR filters can be designed and implemented. The FIR filter 7020 can be physically realized by using digital shift registers 7022 , multipliers 7024 and summers 7026 as shown in FIG. 73 . The discrete signals 7028 are shifted into registers 7022 by a sampling clock pulse 7030 . The registers 7022 hold past values 7032 of the sampled signal 7028 as well as present values 7034 required for mathematical convolution. The past 7032 and present 7034 values are multiplied 7024 by filter weighting coefficients 7036 , summed 7026 and then output 7038 .
[0582] Another way of representing a FIR filter structure 7020 is shown in FIG. 74 . The operation described can be shown to be the equivalent of FIG. 73 since:
[0000] A=c 3 x k−1 Equation (56)
[0000] B=c 3 x k−1 +c 2 x k Equation (57)
[0000] C=c 3 x k−2 +c 2 x k−1 Equation (58)
[0000] resulting in
[0000]
D
=
y
k
=
c
3
x
k
-
3
+
c
2
x
k
-
2
+
c
1
x
k
-
1
+
c
0
x
k
=
∑
j
=
0
3
c
j
x
k
-
j
=
c
k
*
x
k
Equation
(
59
)
[0000] As can be seen in FIGS. 73 and 74 the weighting 7036 of the discrete input samples 7028 relies upon many multipliers 7024 .
[0583] A single channel of a multichannel FIR filter 7040 for CDMA modems is shown in simplified form in FIG. 75A . The multichannel FIR filter 7040 is shown as a single element with a multichannel input sequence x (i)k entering the filter 7040 and the filtered result y (i)k exiting. The subscript “i” identifies which channel from a plurality of channels is being filtered. The multiple single bit data/signal streams represent serial data streams that have been modulated with a pseudo noise (PN) spreading code. Each channel could represent user traffic channels at various data rates. Various types of signaling data might comprise other channels.
[0584] A typical example of an integrated service digital network (ISDN) CDMA modem would require five channels. Two channels would be 64 kbps traffic channels (B 1 and B 2 ), a 16 kbps auxiliary signaling and packet channel (D), an order wire channel (OW), and an ARPC channel.
[0585] For maximum user capacity in a CDMA system it is necessary to use the minimum amount of power to achieve the required BER. Each channel must have the appropriate individual weight applied so that the correct relative amplitudes are transmitted. After the weighting operation the individual data streams become multibit values. The data streams are summed together in a large digital summing circuit that consists of a tree of numerous two input adders. The weighted and summed digital values are then filtered in a conventional FIR filter. The FIR filter is required to pulse shape the input waveforms while suppressing out-of-band emissions. The multipliers in the FIR must handle the multibit data and coefficients to the desired precision.
[0586] In FIG. 75B , four signal channels are input individually into separate FIR filters 7020 , (the clock signal has been omitted for clarity). The individually filtered signals are then weighted using multipliers 7024 with a channel specific weighting coefficient 7037 w (i) for power control, equalizing the power or gain between individual channels, before being input to a multichannel summer 7046 . Since all users occupy the same frequency spectrum and time allocation in spread spectrum communication systems, it is desired that each user is received with the same power level. The result, y (i)k 7044 , is a weighted sum of the individually FIR filtered multiple signal channels.
[0587] A CDMA transmitter combines many channels of varying types of digital signals (serial digital voice, power control, ISDN data). Typically, each channel is modulated with a different spreading code. The spreading code allows a CDMA receiver to recover the combined signals by use of the proper code during demodulation. Alternatively, any set of orthogonal functions could be combined with the preferred embodiment and later separated by correlation.
[0588] The output 7044 of the multichannel FIR filter 7040 is a weighted and filtered average. Although each channel has been described as a single bit valued serial data stream, multi-bit values or levels may be processed with the identical multichannel filter structure.
[0589] Referencing FIG. 76 , the multichannel FIR filter 7040 is shown using four tap FIR filters 7048 . The weighting of the discrete samples is performed by conventional multipliers 7024 . Each FIR structure is comprised of shift registers 7022 and summers 7026 for past 7032 and present 7034 sampled signals. Each tap weight coefficient 7036 is multiplied by the respective channel power control weighting factor 7037 . The result is the same as shown in FIG. 75B , but with the external multipliers inside the FIR 7048 structures.
[0590] Hardware reduction is accomplished by sharing FIR registers and adders as shown in FIG. 77 . Each multichannel processing element 7052 performs part of the channel weighting 7037 , the FIR tap coefficient 7036 multiply 7024 , and the summing 7026 of the multiple channels for that tap. The partitioning of the discrete functions reveals the preferred embodiment.
[0591] FIG. 78 shows the multichannel processing element 7052 as a processing block with “N” single bit input signals x (o)k , x (1)k , . . . , x (N)k . The computed output z k 7054 contains “W” bits of resolution. The discrete input signals 7028 form a vector. This vector can be assigned an overall value by weighting each bit with an increasing power of two. In the alternative, the multichannel signal bits are treated as a binary valued word. The output of the processing block is a “W” bit wide function of the N bit binary input argument. The block performs the equivalent logical function of a memory device where the input signal bits form an address and the computed values are contents of the selected memory word. A memory based LUT 7056 can perform an arbitrary function quickly and efficiently as shown in FIG. 79A .
[0592] A mathematical function ƒ of an argument x with a result of y is expressed as y=ƒ(x). The function performs a mapping of all values of x into another space of y values. A LUT performs this mapping for the values of interest in the preferred embodiment. The LUT memory device is presented with an address of a location within the memory circuit. The value previously stored at that location is delivered to the memory output data bus. The values of interest of x, which are discrete, are mapped into a binary number. Since the multichannel signals are represented by zero or one logic levels, they are used as bits to form a binary number. Every possible combination of channel values is therefore assigned a state number. This operation is represented as:
[0000]
∑
j
=
0
M
-
1
x
j
2
j
=
x
M
-
1
2
M
-
1
+
…
x
3
2
3
+
x
2
2
2
+
x
1
2
1
+
x
0
2
0
=
x
M
-
1
2
M
-
1
+
…
x
3
8
+
x
2
4
+
x
1
2
+
x
0
Equation
(
60
)
[0593] Each state is a binary number that references an address in the LUT. The output value from the LUT is the precomputed value of the function resultant that would occur given the argument corresponding to that address. This is illustrated as a tabular representation of the LUT contents. The function to be performed is the weighted sum of the multiple channels for a given single tap of the FIR structure.
[0594] For example, in an application using 4 channels (M=4), the LUT contents located at the 2nd tap of the multichannel FIR (j=2) would be as shown in Table 16.
[0000]
TABLE 16
Values of x
Address
LUT Value Stored
x 3 , x 2 , x 1 , x 0
Computation of A
At Location A
0 0 0 0
0
0
0 0 0 1
1 = 1
w 0 c 2
0 0 1 0
2 = 2
w 1 c 2
0 0 1 1
2 + 1 = 3
w 1 c 2 + w 0 c 2
0 1 0 0
4 = 4
w 2 c 2
0 1 0 1
4 + 1 = 5
w 2 c 2 + w 0 c 2
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
1 1 0 1
8 + 4 + 1 = 13
w 3 c 2 + w 2 c 2 + w 0 c 2
1 1 1 0
8 + 4 + 2 = 14
w 3 c 2 + w 2 c 2 + w 1 c 2
1 1 1 1
8 + 4 + 2 + 1 = 15
w 3 c 2 + w 2 c 2 + w 1 c 2 + w 0 c 2
[0595] The LUT 7056 memory words contain precomputed values corresponding to the current input address value as shown in FIG. 79B . The memory can be implemented in either ROM or RAM, depending upon the application.
[0596] In the preferred embodiment, ROM (read only memory) is used to store permanent LUT values. This is implemented efficiently as an integrated circuit. ROM is appropriate for time invariant systems where the required channel weights and filter coefficients are known a priori. RAM (random access memory) allows new values to be written over old. LUT values can be computed and loaded to achieve adaptivity. RAM is not as space efficient as ROM but is still efficient considering the increased flexibility.
[0597] The preferred embodiment of the multichannel FIR filter 7040 for CDMA modems according to the present invention is shown in FIG. 80 . The filter structure uses LUTs 7056 rather than the inefficient multichannel processing elements 7052 which require a plurality of multipliers 7024 and summers 7026 .
[0598] The signal bits form the address word which is applied to the LUT 7056 . There is a LUT 7056 for each filter tap required. The contents of each LUT 7056 is computed as:
[0000]
L
j
(
D
N
,
D
N
-
1
…
,
D
2
,
D
1
)
=
C
j
∑
i
=
1
N
D
i
W
i
Equation
(
61
)
[0599] As shown, any combination of signal values has its weighted sum precomputed. The multiplication of each tap coefficient of the FIR function is included in the precomputed table.
[0600] The weighted and filtered single channel operation of FIG. 75A with an N tap FIR can be expressed as
[0000]
y
(
i
)
k
=
w
i
∑
j
=
0
N
-
1
c
(
i
)
j
x
(
i
)
k
-
j
=
w
i
[
c
(
i
)
j
*
x
(
i
)
j
]
Equation
(
62
)
[0000] An M channel multichannel version of this is shown in FIG. 75B and can be expressed as
[0000]
y
(
i
)
k
=
w
i
∑
i
=
0
M
-
1
y
(
i
)
k
=
∑
i
=
0
M
-
1
(
w
i
∑
i
=
0
M
-
1
c
(
i
)
j
x
(
i
)
k
-
j
)
Equation
(
63
)
y
(
i
)
k
=
∑
i
=
0
M
-
1
w
i
[
c
(
i
)
j
*
x
(
i
)
j
]
Equation
(
64
)
[0000] This is the desired weighted sum of convolutions or FIR filtering operations. The convolution is performed in FIR filters 7020 , the weighting in multipliers 7024 and the summation in adders 7046 . The convolution achieved is identical to that originally presented in Equation (64). The summation and weights are a result of the extension to a multichannel process.
[0601] The preferred embodiment shows an improved filter for multichannel CDMA FIR filtering modem applications. It has been shown that the signal processing operation over multiple channels, as shown in FIGS. 75A and 75B , can be implemented using no multipliers and a reduced number of adders.
[0602] While the present invention has been described in terms of the preferred embodiment, other variations which are within the scope of the invention as outlined in the claims below will be apparent to those skilled in the art. | A system for rapidly acquiring a spreading code, used in a code division multiple access (CDMA) system, comprises a generator for generating a first long code and a second long code, with each long code having a length of N chips. The first long code is different from the second long code. A transmitter transmits the first long code and the second long code at a first phase angle and at a second phase angle, respectively, on a carrier signal over a communications channel using radio waves. The first long code and the second long code may be transmitted at an in-phase (I) angle and at a quadrature-phase (Q) angle, respectively, on the carrier signal. From the communications channel, an I acquisition circuit and a Q acquisition circuit may acquire, in parallel, the first long code and the second long code from the I angle and the Q angle, respectively, of the carrier signal by searching, in parallel, N/2 chips of the first long code and the second long code. | 8 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. Ser. No. 10/869,313, filed Jun. 16, 2004, the entire contents of which are hereby incorporated by reference.
FIELD OF APPLICATION
[0002] This invention relates to the use of a neutral protease (NP) for a tissue dissociation.
PRIOR ART
[0003] The DE 44 45 891 A1 describes a recombinant protease (neutral protease, NP) from Clostridium histolyticum and its use for the insolation of cells and cell aggregates. This being, it is started from the fact that, in order to use natural protease for the isolation of cells and cell aggregates at a greater extent, it is necessary to make available the neutral protease in reproducible quality and in big quantities, what is possible due to a recombinant method of production. However, the cloning of the neutral protease is not possible right away since hardly sequences of Clostridium histolyticum are known (clostripain, two collagenases as well as one ribosomal RNA sequence). Thus, conclusions to the Codon usage and thus the restriction of the degeneracy of usable oligonucleotides is not possible. Therefore, the DNA sequence of the neutral protease from Clostridium histolyticum as well as its recombinant production should be made available, namely by a DNA sequence which codes for a proteine with the activity of the neutral protease from Clostridium histolyticum , whereby the DNA sequence is selected from the group
a.) of the DNA sequence shown in SEQ ID NO: 1 or a DNA sequence complementary hereto, b.) nucleic acid sequences which hybridize with the sequence shown in SEQ ID NO, c.) nucleic acid sequences which would hybridize with one of the sequences mentioned in a.) and b.) without the degeneracy of the genetic code.
[0007] The method for the dissolution of cell tissue and release of cells or cell aggregates contained therein is characterized by incubation of the cell tissue with a recombinant neutral protease from Clostridium histolyticum which is made of SEQ ID NO:1 or a sequence which is coded within the scope of the degeneracy of the genetic code for the same amino acid sequence and is the product of a prokaryontic or eukaryontic expression of an exogenous DNA up to the release of the cells or cell aggregates in the desired extent and separation of the cells or cell agregates from the cell tissue parts. The use of the enzyme thus obtained is not demonstrated.
[0008] A ready-made product, produced by the manufacturer from a mixture of certain ratios of collagenases I and II and neutral protease can be seen in U.S. Pat. No. 5,989,888.
[0009] According to this method, a neutral protease which is contained in a collagenase preparation is used so that a high stability of the enzymes is not achieved. Add to this that, when the neutral protease is contained for a longer time in the collagenase, a reduction of the enzyme activity appears with moisture.
SUMMARY OF THE INVENTION
[0010] The aim of this invention is to make available a product, a method for its production as well as its use for a tissue dissociation with which improved isolation results are achieved with respect to yield, viability and integrity of the cells.
[0011] This aim is achieved by a product with the characteristics of claim 1 with a method according to claim 3 and with an use according to claim 9 .
[0012] The product according to the invention consists of a separate A component from a protease (NP) from Clostridium histolyticum which is not contained in a collagenase enzyme preparation and of a separate B component from collagenase or from a collagenase enzyme preparation, whereby for a tissue dissociation the A component is added to the B component in respectively necessary quantities before the beginning of the dissociation.
[0013] The neutral protease used is not made available by a recombinant production.
[0014] The method according to the invention consists in that a separate A component from a neutral protease (NP) from Clostridium histolyticum with a defined content which is not contained in a collagenase enzyme preparation and which is not produced by a recombinant production is mixed to a separate B component from a purified or partially purified collagenase or from a collagenase enzyme preparation with an individual dosage of the quantitative ratios of both components before the beginning of the tissue dissociation.
[0015] The use according to the invention consists in a completely purified neutral protease (NP) not contained in a collagenase enzyme preparation in a respectively selected quantity as an individual admixture to a collagenase or a collagenase enzyme preparation for the tissue dissociation or the isolation of cells or multicellular aggregates, for example made of tissues, for improving the isolation results with respect to yield, viability and integrity of the cells.
[0016] The use of neutral protease together with purified or partially purified collagenase with a defined content of neutral protease with an individual dosage of the quantitative ratios of both components is particularly advantageous, whereby neutral protease is used which is not produced by a recombinant production.
[0017] Because of the product according to the invention and of the use according to the invention of neutral protease for a tissue dissociation, an improvement of the isolation results with respect to yield, viability and integrity of the cells is achieved in that neutral protease (NP) of Clostridium histolyticum is used separately, not contained in a collagenase enzyme preparation, by an individual adding of the neutral protease to a collagenase enzyme preparation or of collagenase or of collagenase I and II for the isolation of cells or cell aggregates of tissues. Neutral protease of Clostridium histolyticum is used. This being, individuality depending on the tissue type and/or condition prevails. The procedure is such that the adding of collagenase and neutral protease takes place respectively depending on the quantity of tissue. The neutral protease is not contained in a collagenase preparation so that a higher stability of the enzymes is achieved. Add to this that no mixture of neutral protease and collagenase produced by a producer and kept in store or in stock is used. Neutral protease and collagenase are combined shortly before the beginning of a tissue dissociation.
[0018] The demonstration of the function by digestion depending on species, condition of the organ and position of the organ is particularly advantageous. Surprisingly, it has shown that solely due to the variation of the addition of neutral protease, the isolation results could be significantly improved with respect to the yield of islet cell equivalents, viability, integrity of the islet cells or islet cell aggregates. This being, the adding of collagenase plays a less critical part since it is an enzyme which is relatively little toxic for the cells. The quantity of neutral protease is more critical since the enzyme has a cell deteriorating action in too big quantities, in too low quantities the tissue dissociation remains uncomplete, thus the yield of isolated islet cells and islet cell aggregates is lower. In order to be able to dose individually the neutral protease, it is important as well that a purified or partially purified collagenase is used which contains low quantities of other proteolytic activities such as that of the neutral protease.
[0019] Advantageous configurations of the invention are the subject of the subclaims.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Optimization of the islet isolation from porcine and human pancreas by donor related enzyme adaptation.
[0021] The isolation of the islets of Langerhans from the pancreatic tissue takes up a special position in the field of the enzymatic cell separation. Contrary to the isolation of other cell types from different tissues, the islet isolation is characterized by the attempt to separate a multicellular cell aggregate, the islet, from another organ, the pancreas, by preserving the morphologic integrity. This aim makes special demands on the methodology applied.
[0022] The semi-automatic digestion filtration method has become established as a standard procedure for the isolation of islets from the pancreas of bigger animals, this method combining an enzymatic digestion with a mechanical dissociation of the pancreas (1). The selection of appropriate collagenolytic enzyms or protease mixtures constitutes a special challenge. These mixtures should, in the ideal case, guarantee a maximal dissociation of the exocrine tissue for a minimal dissociation of the islet tissue. Among the multitude of the enzymes existing in impure collagenolytic protease mixtures, collagenases of the class I and class II have been identified as being essential for the islet release from the pancreas of rats (2, 3) and pigs (4). Since pure collagenases only lead to an insufficient digestion of the pancreas tissue of dog (5) and rat (2), further proteases in form of dispase (6), neutral protease (2) or trypsin (4) seem to be necessary for an efficient release of islets. Own preliminary findings on porcine pancreas also speak for a positively synergitic effect of unspecific “neutral protease” onto the islet release. The acting mechanism of unspecific proteases is possibly the release of collagen fibres due to the proteolytic degradation of proteoglycans so that collagenolytic activities obtain an easier access to their substrates. Furthermore, a stronger hydrolysis of collagen fragments through unspecific protease is discussed (2). An excess of neutral protease can accelerate the proteolytic degradation of collagenase itself though and contribute to the islet disintegration, because of the lysis of protease senstive adhesion molecules (cell adhesion molecules CAM). On the other hand, it could be shown on rats that islets seem to be relatively resistent to the proteolytic action of pure collagenase (2).
[0023] When evaluating the quoted examinations, it must be taken into consideration that the sensitivity of islets to the destructive effect of neutral proteases depends on the species and is determined by the morphological partition pattern of the cell contacts and of the specific character of the collagen matrix (8, 9). So, for the pig, the periinsular collagen content is the lowest among all the species examined until now (dog, human, rat, cow) and the specific character of a protective connective tissue capsule only exists rudimentally (10-12). On the other hand, in this species, the highest number of cell contacts between endocrine and exocrine pancreatic cells is to be found (8). Thus, the requirements which are made to a collagenolytic protease mixture with respect to the activity profile, depends on the donor species which is used. These important findings lead to the development and commercial utilization of enzyme mixtures for the isolation of islets from the pancreas of the rat (Liberase RI©), of the dog (Liberase C©), of the pig (Liberase PI©) and of the human being ((Liberase HI©) by the Roche company. These products differ essentially in the content of neutral protease.
[0024] Besides species depending differences, there are naturally also intraspecific and individual donor variabilities. For the human pancreas donor, above all an age dependent character of factors such as nutritional condition, consumer habits and prior affections induces an enormous variation of the yield after isolation of the islets. As for the pig, above all the donors' age is to be indicated as a highly significant variable for an isolable islet mass, what lets appear that young donors <25 years are in many cases unsuitable for a successful islet isolation (13-15). Age-related changes, such as an increased body mass index (16) which is often associated with a pancreatic fibrillization (17, 18) or a pancreas fatty degeneration (19) increase the isolation ability of islets from the human pancreas. Although these morphological changes let appear even the pancreas of geriatric donors as suitable for the isolation of islets (20), an age-related reduction of the islets functionality is also to be taken into consideration (15, 21, 22). Thus, just an extension of the donors pool with juvenile or young donors would extremely increase the potential for the clinical islet transplantation.
[0025] For the porcine pancreas, the histological differences between adult and young animals which substantially hamper a successful islet isolation from the juvenile pancreas have also been pointed out (11, 23, 24). Furthermore, recent investigations show that even in defined breeding lines, significant differences can be proved between individuals of the same age with respect to the isolable islet mass (25).
[0026] The preceding statements lead to the conclusion that the specific character of different donor factors requires to be individually taken into consideration when treating a donor pancreas. An user specific isolation procedure contains in particular a modification of the collagenolytic protease mixtures which are used by taking into consideration the above discussed histological results. Available enzymes or enzyme mixtures must allow the user the biggest possible flexibility without overstressing him in the complexity of an individual blending. The availability of a pure class I/class II collagenase mixture, as it can be obtained in form of the NB-1 collagenase of the Nordmark/Serva, complies with this requirement to a wide extent. Depending on the respective donor status, a collagenase concentration which must be individually completed respectively by neutral protease should be adjusted.
[0027] The invention will be explained by the following embodiments and examples.
Example 1
[0028] The adaptation of the neutral protease activity successfully supports the isolation of islet cells of pigs after a long-term cold storage.
[0029] In order to save the short ressources of human organs at a wide extent, preliminary tests are carried out with pigs. Among them, we find in particular the titration of limit concentrations of collagenase and neutral protease which is first evaluated on adult (>24 months) porcine pancreata. Since the NB-1 collagenase is first available only in limited quantity, isolations of porcine islets are carried out with NB-8 collagenases. This being, only charges which are characterized by a minimal content of neutral protease and trypsin as well as by the lowest possible content of clostripain are used. Preliminary tests show here that the digestion time and the quantity of the digestible tissue is clearly correlated with the concentration of neutral protease.
[0030] In order to guarantee a constant enzyme concentration for each test series, the distended collagenase quantity will be adapted to the quantity of the tissue used. This is contrary to the propagated Liberase protocol of the Roche company for which a constant enzyme quantity of 500 mg should be used independently of the mass of tissue (26). For three collagenase concentrations which have to be determined preliminarily empirically (for example 4 mg/g organ, 6 mg/g and 8 mg/g), the optimal quantity of neutral protease is iteratively titrated in the range of approx. 0.2-0.6 DMC-U/g organ.
[0000]
[0000]
NB-8 collagenase
Neutral protease
4 mg/g
6 mg/g
8 mg/g
0.2 DMC-U/g
0.3 DMC-U/g
0.4 DMC-U/g
0.5 DMC-U/g
0.6 DMC-U/g
[0031] The digestion duration, the ratio of tissue inserted to digested tissue, the islet yield, the purity and the mean islet size are considered to be relevant isolation parameters. The most effective mixture is tested on 6 organs. The islets which are then isolated are subject to a quality control which considers the functionality and viability of the islets as well in vitro by statical glucose stimulation and membrane integrity colorations as in vivo by means of the diabetic nude mouse bioassays. The presumably best combination of NB-I collagenase and neutral protease should be confirmed by tests with NB-1 collagenase on 8 organs as well.
[0032] Due to empirically collected experience, it is possible to adapt these iterative optimization tests to juvenile (approx. 6 months old) donor pigs and to repeat them in a reduced extent for promising enzyme combinations.
[0033] The same is also valid for the optimization tests with NB-1 collagenase for the human isolation procedure. By practice-orientated consideration of age-related donor factors, two age classes are formed for pancreas donors which reflect the experience obtained until now: <25 years, 25 years. The above mentioned titration scheme for neutral protease should be adapted for human pancreata and carried out for two preliminarily empirically to determined collagenase concentrations (for example 4 mg/g and 5 mg/organ).
[0000]
[0000]
NB-1 collagenase
Donor:
<25 years
>25 years
Neutral protease
4 mg/g
5 mg/g
4 mg/g
5 mg/g
0.5 DMC-U/g
1.0 DMC-U/g
1.5 DMC-U/g
2.0 DMC-U/g
2.5 DMC-U/g
[0034] The presumably most effective combination of NB-1 collagenase and neutral protease is tested for each age class on 6 organs and the isolated cells are subject to a quality control in vitro and in vivo (s. below).
[0035] An individual dosage is possible due to the use of neutral protease with purified or partially purified collagenase with a defined low content of neutral protease. A preparation of the enzyme mixture takes place with respect to units instead of mass, since the specific activity is very unequal.
[0036] The adaptation of the neutral protease activity successfully supports the isolation of islet cells of pigs after a long time cold storage.
Background:
[0037] The enzymatic dissociation of pancreatic tissue through collagenase constitutes a decisive step in the process of the isolation of islet cells. The variability of the pancreatic collagen for different types led to the production of specific enzyme mixtures. However, the enzyme mixtures available at the moment do not offer the possibility to dose individual components by means of individual donor variables, for example the cold ischemia time. We suppose that the individual adaptation of the neutral protease activity could be used as a critical factor of the enzymatic pancreas digestion in order to facilitate the successful release of islet cells. In order to prove this hypothesis, pancreata of pigs have been subject to a cold long-term storage (6.5 hours) before the dissociation took place by means of NB-8 collagenase of Serva which is characterized by a minimal quantity of neutral protease.
Method:
[0038] After sampling, pancreata of no longer used breeding animals have been intraductally distended with NB-8 collagenase, dissolved in a cold UW solution. The definitive collagenolytic activity was 4 FZ-U/g pancreatic tissue. After preliminary experiences, neutral protease (Serva) has been adapted to 0.6 or 0.9 DMC-U/g or 0.14 DMC-U/g for freshly prepared (n=5) or stored pancreata (n=5). Islet cells have been isolated by modified digestion-filtration and purified on a Cobe 2991 by using Ficoll sodium diatrizoate. The quality control comprised the trypane blue exclusion sample and the statical glucose incubation (2.8 to 20 mM glucose). Moreover, the mitochondrial activity has been evaluated by means of the formazan production and at 490 nm determined by using a tetrazolium compound (MTS) and expressed as arbitrary units (AU) per mg proteine.
Results:
[0039] The total digestion time for long-term stored pancreata has been considerably shortened compared to freshly prepared pancreata (48±3 compared to 63±3, P<0.05). No differences have been stated with respect to the pancreas weight and the quantity of digested tissue. After the purification of islet cells which have been isolated with 0.14 or 0.9 DMC-U/g, no significant differences have been stated with respect to the definitive purity (>95%), to the islet partition (>95%) and the recuperation of islet cell tissue (73±9 compared to 72±16). After long-term storage, the islet cell yield was slightly lower compared to freshly isolated preparations (146,000±43,000 compared to 212,000±52,000 IEQ, NS) but not significantly lower. The quality control resulted in an outstanding islet cell viability (99.9±1 compared to 99.4±0.3%, NS), a preserved intracellular insuline content (1720±96 compared to 1760±280 μU/IEQ, NS) as well as a comparable glucose stimulation index (1.7±0.2 compared to 1.5±0.1, NS) after the digestion with 0.14 or 0.6 or 0.9 DMC-U/g. The mitochondrial activity was not different between the islet cells isolated after the long-term storage (0.85±10.06 AU/mg) and freshly prepared cells (0.90±10.11 AU/mg).
Conclusions:
[0040] This study demonstrates with a model of long-term stored porcine pancreata that the individual dosage of single components of an enzyme mixture is useful according to the individual donor variables in order to facilitate the release of islet cells. The individual adaptation of the neutral protease activity could also be useful for the consideration of the warm ischemia, of the donor age and of the fatty or fibrous degeneration of pancreatic tissue.
Example II
Determination of the Optimal Relation of Neutral Protease to Collagenase for the Isolation of Islets of Langerhans
Aim:
[0041] Determination of the optimal relation of neutral protease/collagenase (NPCR) in the enzyme mixture which is used for the isolation of islets of Langerhans. Serva collagenase mixtures with different NPCR are compared with each other and with Liberase and type V collagenase as controls for a rat model.
Background:
[0042] Liberase is at present the universally used enzyme mixture for the isolation of human islets. Its development was a definitive improvement compared with crude collagenases in so far as it was purified, free from endotoxine and showed little its variability from charge to charge for the enzymatic activity.
[0043] However, since the results of the islet transplantation are proceeding quickly, it is necessary to further improve the configuration and standardization of the enzyme mixtures which are available on the market. There is for example no standardization of the released Liberase charges with respect to activities per gram of the product of the different enzymatic components. Thus, there is a considerable variability from charge to charge for the collagenase activity, the activity of the neutral protease and for the NPCR, as this is shown in the analysis certificates of the producer. For this reason, the optimal NPCR for the islet isolation is not known. It is also conceivable that an adapted NPCR could be necessary for each pancreas, according to its structure, the age of the donor, the ischemia time. A new enzyme which is available on the market is Serva collagenase, packed in separate phials with the neutral protease. This allows a specific blending of the two components in order to achieve a predetermined ratio instead of carrying out the isolation with a ratio which has been preliminarily fixed by the producer and which varies from charge to charge. With the rat model, it is to determine which is the optimal NPCR for the islet isolation.
Methods:
[0044] Seven groups of Lewis rats will be used as islet donors. 18 rats will be in each group. The groups will be determined as follows:
Group 1:
[0045] Islet isolation with pure Serva collagenase, without neutral protease (NPCR=0% w/w)
Group 2:
[0046] Islet isolation with Serva collagenase, with a NPCR of 3% w/w
Group 3:
[0047] Islet isolation with Serve collagenase, with a NPCR of 6% w/w
Group 4:
[0048] Islet isolation with Serve collagenase, with a NPCR of 12% w/w
Group 5:
[0049] Islet isolation with Serve collagenase, with a NPCR of 24% w/w
Group 6:
[0050] Islet isolation takes place with Liberase RI.
Group 7:
[0051] Islet isolation takes place with type V collagenase (Sigma).
Example IIA
[0052] The Role of Neutral Protease During the Islet Isolation, Evaluated with a New Enzyme Preparation
Aim:
[0053] Several enzyme preparations are available for the islet isolation. One of them is a highly purified product with separate components (collagenase and neutral protease) which allows the adaptation of the neutral protease concentration for the islet isolation. For this study, we evaluate the role of neutral protease during the islet isolation.
Method:
[0054] Seven groups of Sprague-Daley rats (18 rats per group) have been formed for the standardized islet isolation according to the enzyme type. We charged for group I type XI collagenase by 2 mg/ml (Sigma Chemical, for group II Liberase by 0.6 mg/ml (Roche) and in the groups III to VII NB1 collagenase 0.6 mg/ml (Serva Electrophorese). Pure NB 1 collagenase has been charged for group III. For the groups IV, V, VI and VII, a concentration of 7.5, 15, 22 and/or 30 μg/ml neutral protease (NP) has been added. The results have been evaluated with respect to the islet yields, apoptosis (cell death detection ELISA, Roche and Tunel coloration), of cytokines (IL-1β, IL-6, TNFα, IFNγ) secretions (Quantikine M, R&D system), insulin secretion (statical incubation) and islet morphology (histology and immuno-histology).
Results:
[0055] The endotoxine content of the enzyme solution was for the groups I and II 173+22 and 120+11 EU/ml. For the groups III to VII, it increased gradually, according to the NP concentration, from 0.4 to 58 EU/ml (p<0.05). The islet equivalent (IE) yields per rat were 1367+522 and 1755+110 for group I and/or II. For the groups III to VII, the IE yields per rat followed a Gaussian distribution according to the NP concentration with a higher yield for the group V, 1712+245 and a lower for the group III (597+277) and the group VII (905+297) (p=0.05). For the groups III to VII, the islet morphology was influenced by the NP concentration with a decreasing number of captured islets and an increasing number of fragmented islets as the NP content increased. The increase of the NP concentration was related to a progressive deterioration of the a cell ring of the islet which was comparable for the group VII with the deterioration which has been observed for the groups I and II. The release of cytokines (IL-1β, IL-6, TNFα, IFNγ) was lower in the groups III to VII compared with the groups I and II, however it was not influenced by the NP concentration, the islet cell necrosis and apoptosis were statistically significantly lower in the groups III to VII compared with the groups I and II, however they were not influenced by the NP concentration. The mean stimulation indizes of the insulin secretion were 2.96 for the group I, 5, 17 for the group II and they were between 5.25 and 5.43 for the groups III to VII.
Conclusion:
[0056] Neutral protease is a decisive additive to collagenase for the islet isolation with respect to islet yields. The Serva collagenase with an appropriate concentration of neutral protease can be compared with the Liberase with respect to the islet yields and function. However, it is related with a lower release of islet cell cytokines and to apoptosis, what results in an improved cell morphology.
Example III
Successful Long-Term Preservation of Pancreas by Means of the Two-Layer Method for the Subsequent Isolation of Porcine Islet Cells
Background:
[0057] The special sensitivity of porcine islet cells prevented the successful isolation from pancreata after cold long-term storage. For the successful isolation of human islet cells, the oxygen accumulation in pancreatic tissue has been recently developed by means of the two-layer method (TLM) during the cold storage. Up to now, no data are available about the long-term preservation of porcine pancreata by means of TLM. Therefore, the aim of this study was to examine the efficiency of the TLM for the successful isolation of islet cells of porcine pancreata which have been submitted to a TLM preservation for 6.5 hours (n=5) compared to freshly prepared pancreata (n=5).
Method:
[0058] Immediately after sampling, pancreata of no longer used breeding animals have been intraductally distended with collagenase (Serva), diluted in a cold UW solution with a concentration of 4 mg per g pancreatic tissue. Islet cells have been isolated by modified digestion-filtration and purified on a Cobe 2991 by using Ficoll sodium diatrizoate. The quality control comprised the trypan blue exclusion sample and the statical glucose incubation (2.8 to 20 mM glucose). Furthermore, the mitochondrial activity has been evaluated by means of the formazan production and determined at 490 nm by using a tetrazolium compound (MTS) and expressed as arbitrary units (AU) per mg protein.
Results:
[0059] After purification, no significant differences could be stated between freshly prepared pancreata and TLM preserved pancreata with respect to the definitive purity (>95%), the yield (2440±580 compared to 1800±250 IEQ/g), the viability (99.4±0.3 compared to 100.0±0.0 IEQ/g) and the glucose stimulation index (1.73±0.19 compared to 1.48±0.14, NS) of islet cells. The intracellular insulin content was increased after the TLM preservation compared to the fresh preparation (2250±110 compared to 1760±280 μU/IEQ, NS). Compared to the freshly isolated islet cells, the mitrochondrial activity has been maintained by the TLM during the long-term storage (0.96±0.15 compared to 1.01±0.17 AU/mg, NS).
Conclusions:
[0060] This study demonstrates the efficiency of the TLM for the long-term preservation of porcine pancreata before the successful isolation of islet cells.
Example IV
[0061] Comprises the storage of the tissue (porcine pancreas) with the two-layer method on perfluoro hydrocarbone, tissue dissociation through individual adding of neutral protease.
[0062] Perfluoro hydrocarbone has a high oxygen combining capacity. Thus, the stored tissue is better supplied with oxygen so that the metabolism can be better maintained and the tissue better withstands the storage of a few hours. For the isolation of cells, the digesting enzyme solution has been added either before the storage (TLM preloaded) or after the storage (TLM postloaded). Again the variation possibility of the quantity of the added neutral protease is important (for a constant collagenase concentration of 4 PZ-U/g organ): preload lower quantity (0.1 DMC-U/g organ since a longer digesting time is given by the storage) and postload higher quantity (0.9 DMC-U/g organ).
[0063] This being, optimization of the cell isolation results by variation of the neutral protease and storage method.
Data in the Table I:
[0064] These are the detailed data concerning yield of islet cell equivalents, viability, integrity of the islet cells.
[0065] The data show that the results which can be achieved with respect to yield of islet cell equivalents, viability, integrity of the islet cells or islet cell aggregates are comparably good independently of the storage (2=TLM-preloaded (4 PZ-U; 0.1 DMC-U); 4=UW-preloaded (4 PZ-U; 0.1 DMC-U); 3=TLM-postloaded (4 PZ-U; 0.9 DMC-U) or non storage (6=unstored (4-PZ-U; 0.9 DMC-U)) when the quantity of neutral protease is adapted correspondingly.
[0000]
TABLE I
Isolation result before purification
after purification
Exp. Grp.
IEQ Pre
SEM
n
IEQ/IN Pre
SEM
n
IEQ Post
SEM
n
IEQ/IN Post
SEM
n
6
382457
69415
6
0.81
0.0
6
388877
100179
6
0.90
0.09
6
3
245500
51272
6
0.73
0.15
6
238550
37398
6
0.69
0.10
6
2
309357
32394
7
0.84
0.08
7
210429
22852
7
0.68
0.06
7
4
192229
22 97
7
0.72
0.07
7
108957
34 9
7
0.60
0.0
7
after purification
Exp. Grp.
IEQ . (%)
SEM
n
OD/10 3 IE
SEM
n
Si
SEM
n
mU/10 3 IE
SEM
6
97.5
15.6
6
0.701
0.048
6
2.76
0.42
6
13
3
104.6
18.7
6
0.760
0.043
6
1.
0.29
6
8
2
69.1
4.6
7
0.7 2
0.030
7
1.47
0.15
7
3
4
83.
.2
7
0.803
0.034
7
1.56
0.15
7
1060
13
Significance: ns ns ns 3:2 ns 6:2 ns
6 = without storage (4 PZ-U, 0.9 DWC-U)
3 = TLM storage, enzyme addition after storage (4 PZ-U, 0.1 DMC-U)
2 = TLM storage, enzyme addition before storage (4 PZ-U, 0.1 DMC-U)
4 = Storage in UW buffer, enzyme addition before storage (4 PZ-U, 0.1 DMC-U)
IEQ/IN = Fragmentation index
OD = Mitochondrial activity
MU = Insulin content
indicates data missing or illegible when filed | The use of a neutral protease (NP) together with a collagenase consists in that a neutral protease which is not contained in a collagenase enzyme preparation and which is not produced by a recombinant production is mixed before the beginning of a tissue dissociation with a collagenase or a collagenase enzyme preparation with an individual dosage of the quantitative proportions of neutral protease and collagenase for improving the isolation results with respect to yield, viability and integrity of the cells. | 2 |
FIELD OF THE INVENTION
The present invention relates to a novel method for the preparation of basic poly aluminum sulphate.
BACKGROUND OF THE INVENTION
Poly aluminum sulphate is a relatively new product that has been extensively developed over the past few years especially for the field of water purification where it is useful as a flocculating agent.
Various processes for the preparation of poly aluminum sulphate have been developed over the years. Traditional methods follow a partial neutralization of aluminum sulphate (Alum) with hydroxyl groups from lime, caustic soda, soda ash, ammonium hydroxide or other alkali sources to a pH of approximately 3.5 to 4.3. Typically, the pH value tends to be 3.8 because aluminum hydroxide is not precipitated at or below this pH value.
Stabilizers such as phosphates, or chlorides may also be added to partially replace sulphate groups, or alternatively organic complexing agents such as sodium heptonate, citric acid, sorbitol, sodium citrate, sodium tartrate, sodium gluconate and the like may be added separately to stabilize the aqueous poly aluminum sulphate as much as possible. For a good review of the various processes that have been developed over the years for synthesizing poly aluminum sulphate, one may refer to Canadian Pat. Nos. 1,123,306, 1,203,364, 1,203,664 or 1,203,665 and to U.S. Pat. Nos. 4,284,611 and 4,536,384.
For instance, in Canadian Pat. No. 1,203,364, Alum is neutralized with sodium hydroxide to prepare an aluminum hydroxide gel according to the following reaction:
4Al.sub.2 (SO.sub.4).sub.3 +24NaOH)→8Al(OH).sub.3 +12Na.sub.2 SO.sub.4
Next, poly aluminum sulphate is prepared from this gel according to the following reaction:
8Al(OH).sub.3 +4Al.sub.2 (SO.sub.4).sub.3 →4Al.sub.4 (OH).sub.6 (SO.sub.4).sub.3
This reaction yields a 50% basic product.
Using this method, 4 moles of poly aluminum sulphate and 12 moles of sodium sulphate by-product are obtained, thereby representing a significantly disadvantage. A further considerable disadvantage of this method is that a "filter cake" of aluminum hydroxide gel must be prepared before the desired product can be synthesized. Therefore, this supposes a two-step process from which large amounts of by-products are obtained.
Canadian Pat. No. 1,203,364 also teaches the neutralization of sodium aluminate with sulfuric acid to produce an amorphous aluminum hydroxide gel according to the following reaction:
4Na.sub.2 Al.sub.2 O.sub.4 +4H.sub.2 SO.sub.4 +8H.sub.2 O→8Al(OH).sub.3 +4Na.sub.2 SO.sub.4.
This gel is then further reacted with Alum to produce basic poly aluminum sulphate. Then for a 50% basic product:
8Al(OH).sub.3 +4Al.sub.2 (SO.sub.4).sub.3 →4Al.sub.4 (OH).sub.6 (SO.sub.4).sub.3
we note that although most of the sodium sulphate is removed from the aluminum hydroxide gel through filtration, it remains nevertheless a wasted and costly by-product. Again, this is a two-step process which is difficult to perform because one must also go through the production of a "filter cake" of aluminum hydroxide gel. This yields 4 moles of by-product per 4 moles of product.
The processes described in the remaining above-mentioned patents, which do not require a prior hydroxide gel formation, still present serious drawbacks. For example, with these processes, it is difficult to produce a concentrated marketable product containing the required typical 7 to 10% of Al 2 O 3 concentration because diluted alkalies must be added slowly to Alum in order to prevent simultaneous precipitation of aluminum hydroxide. Furthermore, in most instances, by-product losses are considerable. Solutions containing substances such as calcium or sodium sulphate or ammonium sulphate are the by-products that are usually generated when the processes described in the patents cited above are used. Typically, a by-product loss ranging from 20 to 30% by weight depending on basicities produced and sources of alkali used is almost unavoidable.
Mixing and filtration problems are also associated with most of the processes known in the art. For example, when lime is used as the alkali in the process, serious mixing and filtration problems can be encountered. Also, crytallisation problems will unavoidably be encountered when sodium sulphate is formed as a by-product.
Therefore, although the technical advantages of poly aluminum sulphate have been recognized for several years, there are still some serious problems associated with its preparation and handling. It appears that it would be highly desirable to provide a process that would minimize the losses that can be encountered through the production of by-products as well as problems associated with the separation of these by-products.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a novel method for the preparation of a poly aluminum sulphate product having the following general formula:
[Al.sub.A (OH).sub.B (SO.sub.4).sub.C (H.sub.2 O).sub.E ].sub.n
in which
n is a positive integer;
A is 1.0;
B ranges from 0.75-2.0;
C ranges from 0.5-1.12; and
E is 1.5 to 4 when the product is in solid form; and
E is larger than 4 when the product is in aqueous form, and wherein
B+2C=3.
This method comprises the step of reacting Alum with an alkali aluminate under high shear mixing and recovering the desired product.
The most important advantages resulting from the use of the product of the process of the present invention is the fact that smaller amounts of by-product for given amounts of product are produced and the formation of an aluminum hydroxide gel "filter cake" is avoided.
The method of the present invention represents a clear breakthrough in the preparation of poly aluminum sulphate because it reduces the amount of by-products to approximately 25% of the by-products that were obtained with most of the already existing methods. Furthermore, the major by-product (sodium sulphate) being obtained in lesser amounts, it can be maintained in the final product to enhance its performance since the level of by-product obtained will not lead to crystallisation of sodium sulphate at ambiant temperatures.
The process of the present invention will be more detailed in the following description.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a process for the preparation of poly aluminum sulphate or other poly aluminum compounds of the same generic family.
The product
The product to be prepared in accordance with the present invention is a poly aluminum sulphate having the following general formula:
[Al.sub.A (OH).sub.B (SO.sub.4).sub.C (H.sub.2 O).sub.E ].sub.n
in which
n is a positive integer;
A is 1.0;
B ranges from 0.75-2.0;
C ranges from 0.5-1.12; and
E is 1.5 to 4 when the product is in solid form; and
E is larger than 4 when the product is in aqueous form, and wherein
B+2C=3.
The value of integer n will increase as the basicity of the product increases.
The starting materials
Basically, two starting materials are required to perform the novel process of the present invention. First, aluminum sulphate referred to in the general trade as Alum must be employed. Aluminum sulphate has the following formula: Al 2 (SO 4 ) 3 . The second starting material is a source of a suitable alkali aluminate. Although sodium aluminate is the preferred starting material, other suitable alkali aluminates may also be contemplated. Water is also necessary since the reaction will be performed in an aqueous medium.
The process
The process for preparing poly aluminum sulphate in the context of the present invention involves a unique batch procedure in which Alum is reacted with an alkali aluminate under "high shear" mixing. Generally speaking, from 5666 to 8719 parts of liquid Alum having a concentration in Al 2 (SO 4 ) 3 of 28% is cooled to a temperature that may range between 10° and 35° C. and under "high shear" rate producing a typical peripheral velocity of 20 to 90 feet/second is added from 639 to 1704 parts of liquid alkali aluminate having a concentration of 24% Al 2 O 3 and 6% free NaOH when the alkali aluminate is sodium aluminate contained in at least 320 to 843 parts of additional water respectively over a period of time typically ranging from 1/4 to 11/2 hour. The reaction mixture is maintained at a temperature ranging from 10° to 35° C. for a period of time typically ranging from 1/4 to 11/2 hour after which the reaction temperature is slowly increased to a range that can vary from 50° to 90° C. over a period of time typically ranging from 1/2 to 21/2 hours. This final temperature is then maintained for a period of time typically ranging from 1/2 to 2 hours or until the mixture becomes clear. Once the resulting mixture is clear, it is cooled to room temperature. It is to be noted that for this reaction, the pH of the solution should be maintained between 2.0 and 3.8.
Alternatively, the alkali aluminate can be added to part of the required amount of Alum, thereby producing a pH ranging from 5 to 9 in order to form a neutralized gel and the remaining required amount of Alum can then be added to form the final reaction product. If the reaction is performed in this fashion, the pH variations during the process will usually vary from 2.0 to 9.0. As for temperatures and mixing times, the temperature, when alkali aluminate is added to Alum, will range between 10° and 35° C. and will range from 35° to 90° C. after the remaining amount of Alum is added to the reaction mixture. Mixing times after addition will typically range from 1/4 to 11/2 hour for the first half of the reaction and from 1 to 41/2 hours for the second half of the reaction.
Another alternative reaction sequence consists in adding a part of the total Alum to the alkali aluminate to form a neutralized gel. This first part of the total amount of Alum should be such as to produce a pH ranging between 5 and 9. The remaining amount of total Alum is then added to the reaction mixture to form the final product. In this case, the pH of the reaction will vary from 14 to 3.7. As for the temperatures, they will range from 10° to 35° C. for the first part of the reaction and from 35° to 90° C. for the second part of the reaction. Mixing times will also vary depending on the performed step. In the first part, the mixing time after addition will typically range from 1/4 to 11/2 hour while it will range from 1 to 41/2 hours in the second part.
It is to be noted that the process described above may also include the addition of substantial amounts of other cations such as those of iron contained in Alum when it is prepared from bauxite. Other cations, whether introduced unentionally or otherwise, may include magnesium, calcium, zinc, zirconium and the like. Furthermore, one may also forsee the optional addition of other anions such as phosphates, chlorides, acetates, borates, carbonates or salts of organic or inorganic acids when added to the basic Alum complex.
In a preferred embodiment of the present invention, from 1022 to 1534 parts of sodium aluminate having a concentration in Al 2 O 3 of 24% and 6% free NaOH, contained in at least 1244 to 1867 parts of additional water respectively is added to from 6154 to 7620 parts of liquid Alum having a concentration of Al 2 (SO 4 ) 3 of 28% and which has been previously cooled to a temperature ranging from 10° to 20° C. It is to be mentioned that sodium aluminate is to be added slowly on a period of time ranging from 1/2 to 3/4 hour under high shear mixing. The resulting mixture is held at a temperature ranging from 10° to 20° C. for a period of time ranging from 1/2 to 3/4 hour after which the temperature is slowly increased to 20° to 70° C. over a period of time ranging from 1 to 2 hours. The mixture is held at this final temperature for 3/4 to 11/2 hour or until the mixture becomes clear. The resulting mixture is then cooled and ready to use.
The equations describing the reaction for the preparation of poly aluminum sulphate when using Alum and sodium aluminate are as follows for the preparation of a 50% basic Alum:
I 3Na.sub.2 Al.sub.2 O.sub.4 +Al.sub.2 (SO.sub.4).sub.3 +12H.sub.2 O→8Al(OH).sub.3 +3Na.sub.2 SO.sub.4
II 8Al(OH).sub.3 +4Al.sub.2 (SO.sub.4).sub.3 →4Al.sub.4 (OH).sub.6 (SO.sub.4).sub.3
therefore the overall reaction is
III 3Na.sub.2 Al.sub.2 O.sub.4 +5Al.sub.2 (SO.sub.4).sub.3 +12H.sub.2 O→4Al.sub.4 (OH).sub.6 (SO.sub.4).sub.3 +3Na.sub.2 (SO.sub.4)
Thus, by using simultaneously acid and alkali aluminum salts, the product:by-product ration obtained is substantially higher than any ratio obtained with previously known methods. Only three moles of sodium sulphate per 4 moles of final product is obtained with the method of the present invention.
One must appreciate that the important feature of the present invention is the use of high shear mixers (homogenizers) which enable the formation of the reactive Al(OH) 3 gel at a high solids content. This yields a final transparent liquid product having a concentration of Al 2 O 3 ranging from 7 to 10% obtained from a unique batch procedure.
The following examples are introduced to illustrate rather than limit the scope of the present invention.
EXAMPLE 1
Preparation of polymeric basic aluminum sulphate.
700 parts of liquid Alum (28% Al 2 (SO 4 ) 3 ) was added to a jacketed 1 L. flask. The mixture was cooled to 15° C. and under high shear mixing, 129 parts liquid sodium aluminate (24.0% Al 2 O 3 ) contained in 157 parts of additional water were slowly added over one half hour. The aluminum hydroxide gel mixture was held at 10°-15° C. for one half hour at which time the temperature was slowly increased to 65° C. over two hours. It was held for one and a half hour at 65° C. until the mixture became clear and was then cooled. The product obtained contained 9.2% Al 2 O 3 (a partial increase over theoretical due to evaporation loss) and had basicity of 50%.
EXAMPLE 2
Preparation of polymeric basic aluminum sulphate.
284 parts water were added to 244 parts of liquid Alum and cooled to 15° C. liquid sodium aluminate (24% al 2 O 3 ) 135 parts diluted with 143 parts water was then added over one half hour to a pH of 6.1, the gel was mixed for one half hour under high shear. Alum liquid 456 parts, was then added and the temperature slowly raised over 11/2 hour to 58° C. and held at 58° C. for an additional 11/2 hour. Upon clearing the product was cooled and contained Al 2 O 3 7.0% (partial increase due to evaporation loss) and a basicity of 51.5%.
EXAMPLE 3
Preparation of polymeric basic aluminum sulphate.
To 459 parts water, were added 140 parts sodium aluminate (24.0% Al 2 O 3 ). Next 255 parts liquid Alum were added under high mixing at 20° C. over 1/2 hour. The pH was 5.6 and after 3/4 hour of mixing 445 parts of liquid Alum were added, and the temperature was kept at 20° C. for an additional 11/2 hour. It was then increased to 58° C. over 11/4 hour and held for 1/2 hour at which time the mixture became totally clear. The product was cooled and showed a basicity of 52.7% and 7.3% Al 2 O 3 .
EXAMPLE 4
Comparison tests involving Alum and poly aluminum sulphate prepared in accordance with the present invention.
Tests were carried out using Alum or poly aluminum sulphate having a basicity of approximately 50% using water taken from the St-Lawrence river, the treatment being performed at 25° C. and 8° C. The tests were carried out using Alum as a reference and both tests had an Al 2 O 3 content of 6.9 mg/L. Results are shown in Tables I and II.
TABLE I______________________________________ ALUM PAS______________________________________Beaker 1 142Al.sub.2 O.sub.3 ppm 6.9 6.9APP. OF FLOCPin Pointmins., sec. 3.00 1.30FLOC FORMATION7 minutes 1 215 minutes 1.5 2.520 minutes 2 2.5Position of floc D CBeaker 1 142ANALYSIS OFOVERFLOWTurbidity (NTU) 0.56 0.32Alkalinity (CaCO.sub.3) 37 45pH 7.04 7.34______________________________________RAW WATER AGITATION SETTLING______________________________________pH 8.46 3 min. at 100 rpm 10 minutesAlkalinity CaCO.sub.3 52 15 min. at 25 rpmTurbidity NTU 2.6 10 min. at 5 rpmTemperature °C. 8______________________________________ FLOC POSITIONFLOC FORMATION SETTLING AT 10 RPM______________________________________No floc 0 Nil 0 Dispersion DTurbidity 1 Poor 1 Centre CPin point 2 Slow 2Good 3 Fast 3Very good 4 Very fast 4______________________________________
TABLE II______________________________________ ALUM PAS______________________________________Beaker 1 142 2Al.sub.2 O.sub.3 ppm 6.9 6.9APP. OF FLOCPin Pointmins., sec. 0.45 1.15FLOC FORMATION7 minutes 2 2.513 minutes 3 320 minutes 3.5 3.5Position of floc C CANALYSIS OFOVERFLOWTurbidity NTU 0.29 0.32Alkalinity CaCO.sub.3 38 45pH 7.04 7.34______________________________________RAW WATER AGITATION SETTLING______________________________________pH 8.46 3 min. at 100 rpm 10 minutesAlkalinity CaCO.sub.3 52 15 min. at 25 rpmTurbidity NTU 2.6 10 min. at 5 rpmTemperature °C. 25______________________________________ FLOC POSITIONFLOC FORMATION SETTLING AT 10 RPM______________________________________No floc 0 Nil 0 Dispersion DTurbidity 1 Poor 1 Centre CPin point 2 Slow 2Good 3 Fast 3Very good 4 Very fast 4______________________________________
It is to be noted that in 8° C. water, the residual turbidity of the poly aluminum sulphate prepared in accordance with the present invention is 0.32 NTU while the residual turbidity of Alum was 0.56 NTU. Furthermore, the rate of floc development was faster and the floc larger for the poly aluminum sulphate prepared in accordance with the process of the present invention. Finally, in all cases, the alkalinity of the treated water is higher when poly aluminum sulphate is used relative to Alum. It is also to be noted that at 25° C., even though comparable results are obtained for both products, such warm waters are not frequently treated. | The present invention relates to a process for the preparation of a poly aluminum sulphate product having the following formula:
[Al.sub.A (OH).sub.B (SO.sub.4).sub.C (H.sub.2 O).sub.E ].sub.n
in which
n is a positive integer;
A is 1.0;
B ranges from 0.75-2.0;
C ranges from 0.5-1.12; and
E is 1.5 to 4 when the product is in solid form; and
E is larger than 4 when the product is in aqueous form, and wherein
B+2C=3,
said process comprising reacting an Alum solution with a suitable alkali aluminate under high shear mixing and recovering the desired product. | 2 |
This application is a divisional of U.S. Ser. No. 08/503,978 entitled "Method and Apparatus for Filleting the Body of Slaughtered Poultry" filed on Jul. 19, 1995 by Petrus C. H. Janssen and Adrianus J. Van Den Nieuwelaar, now U.S. Pat. No. 6,007,416.
BACKGROUND OF THE INVENTION
This invention relates to a method and an apparatus for removing automatically at least the inner fillets from slaughtered poultry or a part thereof. The inner fillets, also called tenderloins or tenders, are a part of the bird particularly valued by consumers and therefore valuable, provided that they are of good quality. The inner fillets usually remain behind on the carcass when the outer fillets, also referred to simply as breast fillets, are removed from the carcass.
DISCUSSION OF THE PRIOR ART
In the prior art various methods and apparatuses are known for the removal of, in particular, the inner fillets from the carcass of a bird.
U.S. Pat. No. 4,477,942 discloses how, after the outer fillets have first been peeled off mechanically, the inner fillets are first cut free in the vicinity of the shoulder joints, whereupon the inner fillets are pulled off the carcass by hand.
In U.S. Pat. No. 4,048,155 it is disclosed how, after the removal of the wings and the outer fillets, the inner fillets are removed from the rib cage by first cutting the inner fillets free mechanically and pushing them away from the ribs with the aid of a pair of obliquely extending knives cutting on each side of the breastbone, and then scraping the inner fillets from the carcass with the aid of a pair of scrapers. The scrapers are provided with rubber inserts whose edges apply the scraping action. The inner fillets scraped loosed are received in a receptacle.
U.S. Pat. No. 4,827,570 discloses that, after the removal of the outer fillets, the inner fillets are removed mechanically by first cutting into the connections between the clavicle, the carcass and the inner fillets at a point along the clavicle by means of knives. The inner fillets are thereupon further freed from the clavicle by means of two successive sets of peeling fingers, whereupon the inner fillets are ploughed entirely free from the carcass, starting form the shoulder joint of the carcass, in the direction of the belly side of the latter, with the aid of scraping elements.
U.S. Pat. No. 4,937,918 discloses how the membranes securing the inner fillets to the carcass are mechanically removed from the carcass by cutting through them with the aid of rotating knives after the removal of the outer fillets. The inner fillets are then partly ploughed loosed from the carcass with the aid of discs, and finally the inner fillets are removed by hand from the carcass.
U.S. Pat. No. 5,314,374 discloses the removal of inner fillets from a poultry carcass conveyed on a carrier, by first cutting and plowing the inner fillets almost completely free from the carcass, and next gripping the inner fillets with a pair of jaws pulling the inner fillets free from the carcass transversely to the direction of conveyance.
In European Patent Application No. 168,865 the starting point is a different method: before the removal of the breast meat, that is to say the outer fillets and the inner fillets, a part of the clavicle is removed. Use is made of scraping elements in the removal of the breast meat.
A difficulty in the methods and apparatuses of the prior art is that the mechanical scraping process indicated therein compresses the inner fillets to a greater or lesser extent in the longitudinal direction, whereby by flesh structure of the inner fillets is damaged. This has the consequence that the appearance of the inner fillets obtained in this manner is less attractive to the consumer and that they go of more quickly.
Another difficulty in the prior art is that the membrane of the inner fillets is damaged or is left on the carcass, so that the place where the membrane adheres to the inner fillets in the natural state a frayed meat surface structure is formed, which impairs the quality of the meat in the same way as is described above.
With the usual methods, a small part of the meat of the inner fillets near the clavicle remains on the carcass after the removal of the inner fillets, because the latter must be cut free from the breastbone with due regard to a safe distance from the clavicle. If this distance is too short there is in fact a great risk that the clavicle will come into contact with a cutting or scraping element and that splinters of bone or particles of the clavicle will remain in the inner fillets. This cannot be tolerated from the point of view of product quality and liability for the product. The consequence of all this is that after the removal of the inner fillets not inconsiderable amounts of meat remain on the carcass.
As an additional difficulty it should also be stated that in the methods of the prior art the inner fillets are frequently detached from the carcass in such a manner that considerable damage is done to the structure of the meat surface in the area where the separation is made.
The object of the invention is to provide a method and an apparatus by means of which inner fillets can be removed mechanically and automatically from the carcass of a bird, while the greatest possible amount of meat is obtained and damage to the meat is prevented as much as possible.
This object is attained according to the invention by a method wherein prior to scraping off the inner fillet the membrana sternocoracoclavicularis is released by making a separation in the opening defined by the natural position of the clavicle and the breastbone. The making of a separation in this position has the consequence that absolutely no residues of meat remain behind on the carcass after the removal of the inner fillets.
Before the inner fillet is scraped away from the body of the poultry the connection between the membrane of the inner fillet and the breastbone in the region of the coracoideum is preferably broken. With freshly slaughtered products this process can be carried out either before or after the breaking of the connection between the inner fillet and the clavicle in the manner described above. If the product is matured and therefore more vulnerable, it is preferred to carry out this process after the breaking of the connection between the inner fillet and the clavicle.
In order to leave the membrane of the inner fillet as far as possible intact, the inner fillet is only partly scraped away form the body of the poultry, after which the part already scraped away is gripped and the inner fillet is pulled free from the body of the poultry substantially in front of the breast thereof. By leaving the membrane intact, the surface structure of the meat under it is kept intact, so that the inner fillet has an attractive appearance and will keep for a long time.
According to the invention an apparatus for the automatic removal of at least an inner fillet from slaughtered poultry or a part thereof comprises a carrier for fixing thereon the poultry of a part thereof, at least comprising the breast with the inner fillets attached, separating elements for the inner fillets, which elements are adapted to be inserted, on opposite sides of the breastbone, into the openings defined by the natural position of the clavicle and the breastbone for the purpose of releasing the membrana sternocoracoclavicularis, the scraping means for scraping off the inner fillets from the body of the poultry. The carrier usually forms part of a conveyor. It may for example have the configuration described in European Patent Application No. 551,156. In such a case the scraping means and the separating elements may be arranged--if necessary movably--along the path of the conveyor. It is naturally also possible to install the carrier in a fixed position and to make the scraping means and separating elements movable.
In a preferred embodiment the apparatus according to the invention comprises membrane separation means for breaking the connection between the membrane of the inner fillets and the breastbone in the region of the coracoideum. The membrane thus continues to cover the outer surface of the inner fillets even after they have been removed from the body of the poultry, which is advantageous for their appearance and for the keeping properties of the inner fillets.
In another preferred embodiment the apparatus according to the invention comprises inner fillet removal means for gripping the inner fillet and pulling it free from the body of the poultry substantially in front of the breast thereof.
The separating elements for a set of inner fillets expediently consist of two substantially parallel plates facing one another and having a free end, the plates being mounted resiliently in relation to one another and in relation to a holder, said holder being movable in a controlled manner relative to the carrier. The ends of the plates have dimensions such that they can without difficulty pass through the openings bounded by the clavicle (if present) and the breastbone. In order to be able to follow the contour of the breastbone as closely as possible, the distance between the plates is shorter than the maximum width of the breastbone. In addition, the resilient connections between the holder and the plates ensure that the plates can easily and accurately follow the contours of the breastbone. The edges of the free ends of the plates are blunt, optionally with the exception of the front side, which may be sharp, thus preventing splinters of bone from being cut off from the breastbone or the clavicle and passing into the inner fillets.
In an advantageous embodiment the membrane separation means for a set of inner fillets comprise two rotatable discs extending generally in one and the same plane. By moving the discs along the rib cage of the bird, on the underside of the inner fillets, the inner fillets are propelled upwards and the connection between the membrane of the inner fillets and the breastbone in the region of the coracoideum can thus be broken. A good propelling action of the discs is obtained by providing their circumferential edge with a frustoconical shape. The circumferential edge of the discs is preferably provided with at least one radially projecting knife for an additional controlled separation of the inner fillet membrane from the breastbone.
In a preferred embodiment the scraping means for a set of inner fillets consist of two scraper plates mounted resiliently at an angle to one another and to a holder, the holder being movable in a controllable manner relative to the carrier, while the scraper plates are adapted to be placed on opposite sides of the clavicle and then on the latter and to be moved along the breastbone away from the clavicle. The distance between the scraper plates is preferably shorter than the maximum width of the breastbone. By means of the abovedescribed measures a scraping action is obtained which extends over the entire surface over which the inner fillets cover the rib cage.
In an expedient and simple embodiment the carriers form part of a conveyor along whose path the separating elements, the membrane separation means and the scraping means are installed.
Another method according to the invention for automatic removal of at least an inner fillet from slaughtered poultry or a part thereof, the poultry or part thereof comprising at least a part of the humerus appertaining to said inner fillet comprises the steps of making an incision in a shoulder joint of the poultry, severing the processus acrocoracoideus in order to open the canalis triosseus, the connection between the inner fillet and the appertaining humerus remaining generally intact; and separating the inner fillet from the poultry by acting on the humerus. By thus opening the canalis triosseus the tendon connection, enclosed therein, between the humerus and the appertaining inner fillet can leave the canalis triosseus when the humerus, or the wing of which the humerus forms part, is used to pull off the inner fillet from the body of the bird. Because the processus acrocoracoideus is cut through, it is possible for the first time for an outer fillet to be torn away from the body, simultaneously with the inner fillet lying under it, by means of its tendon connections to the humerus, with the aid of the humerus or the wing. It may here be observed that, in order to obtain the largest possible amount of meat, an incision can also be made in the shoulder, along the shoulder blade, before the fillets are pulled free from the body. However, this shoulder cut is already generally known for the purpose of pulling only the outer fillets off the bird with the aid of the humerus or of the wing.
Cutting through the processus acrocoracoideus in the shoulder joint is greatly facilitated and its reliability is greatly increased it, before the incision in the shoulder joint is made, a force is exerted on the humerus to position the tendon connecting the humerus to the inner fillet in the canalis triosseus on the side of the latter which is directed towards the breastbone. By the last-mentioned measure the caput humeri of the humerus is brought away from the shoulder joint, so that a cutting element can in a simple manner cut through the processus acrocoracoideus as is desired. The risk that the tendon connection between the humerus and the inner fillets will be touched by the cutting element is greatly reduced by this measure.
A very reliable way of moving the humerus in the desired direction is achieved if the caput humeri is pressed in the direction of the ribs in relation to the scapula and the coracoideum.
Preferably, before an incision is made in the shoulder joint, the shoulder joint is accurately positioned, relative to a cutting element, against a stop which acts on the shoulder joint on the side facing away from the humerus.
In order to prevent damage to the inner fillets while they are being scraped free in the vicinity of the lamella of the clavicle and the breastbone point, the clavicle is removed before the filleting. In the prior art various apparatuses are known for this purpose. When the clavicle has been removed, it cannot be accidentally touched in the cutting-through of the processus acrocoracoideus.
According to the invention an apparatus for automatic removal of at least an inner fillet from slaughtered poultry or a part thereof comprises a carrier for fixing thereon the poultry or a part thereof, at least comprising the breast with at least a part of the wings and with the inner fillets attached; and shoulder joint positioning means for positioning a shoulder joint in relation to a cutting element for cutting through the processus acrocoracoideus of the shoulder joint.
In a preferred embodiment the carrier forms part of a conveyor, and the carrier is composed of an elongated conical support element which is arranged to move the poultry or part thereof with the breast or the rear side thereof in the conveying direction of the conveyor, the cutting element preferably being installed along the path of the carrier, and the shoulder joint positioning means comprising a guide which extends substantially parallel to the path of the carrier and is adapted to make contact with the shoulder joint on the side racing away from the humerus, while the cutting means are arranged for cutting from the humerus side.
In another preferred embodiment the apparatus has humerus positioning means for displacing the humerus in the direction of the ribs of the poultry in relation to the remainder of the should joint, which humerus positioning means may comprise a guide which extends substantially parallel to the path of the carrier and is adapted to make contact with the caput humeri and to displace the latter in the downward direction. In this embodiment the cutting element can in a simple manner act substantially transversely to the path of the carrier and in the horizontal direction.
To prepare for filleting process, according to the invention the skin of slaughtered poultry or a part thereof, at least comprising the breast with at least a part of the wings, is accurately and reliably removed by cutting through the skin at least almost completely between the upper side of the shoulder joint and the wing axilla, next the skin is removed from the lateral side of the poultry body, and next the skin is removed from the breast of the poultry. An apparatus for this purpose according to the invention comprises a carrier for fixing thereon the poultry or part thereof, at least comprising the breast with at least a part of the wings, said carrier forming part of a conveyor and being able to be brought into a first position in which the breast side of the bird is directed transversely to the conveying direction of the conveyor, and being able to be brought into a second position in which the breast side or the rear side of the bird is directed in the conveying direction, while in succession the carrier in its first position passes cutting means installed along the path of the carrier for the purpose of making an incision in the skin between the upper side of the shoulder joint and the wing axilla; in its second position passes a set of rotatable helically ribbed skin removal rollers installed parallel to the path of the carrier for the removal under the wing of the skin of the lateral side of the body of the poultry, and in its first position passes a set of rotatable helically ribbed skin removal rollers installed parallel to the path of the carrier for the removal near the breastbone of the skin of the breast of the poultry.
To prepare for filleting process, the front half of a slaughtered bird is in accordance with the invention placed on a carrier by successively hanging a slaughtered, eviscerated bird by its legs on a suspension element, separating a front half, comprising the breast, from a back half, comprising the hips and the legs, except for a connection on the rear side of the bird between the front half and the back half, whereupon the front half is mounted on the carrier and said connection is broken. By retaining at first a connection between the front half and the back half on the rear side of the bird, the front half comes to hang with the breast side directed downwards under the back half. In the opening at the belly side which is produced in the front half by the separation of the back half from the front half, a generally cone-shaped carrier can easily be fitted automatically, and is able to carry it along after the remaining connection between the back half and the front half has been broken.
For preference the front half is conveyed along a first path and the carrier is conveyed along a second path, the front half and the carrier moving next to one another at substantially the same speed, with the breast side of the front half facing the carrier, and the first path and the second path converging at least until the front half is mounted on the carrier. Another advantageous way of fitting a carrier in the front half is by conveying the front half along a first path with the breast in the conveying direction, and conveying the carrier along a second path, the front half and the carrier moving towards one another along the first and second paths respectively, at least until the front half is situated on the carrier. There is thus great freedom in the conveying of slaughtered birds, with the front half cut free from the back half with the exception of the rear connection, and in the conveying of the separated front halves on carriers. The first and second paths should come together only in the region in which the front half is brought onto the carrier.
According to the invention the apparatus for mounting a front half of a slaughtered bird on a carrier is designed such that the carrier forms part of a first conveyor and is composed of an elongated conical support element which is arranged so that its end is directed at an angle to the vertical towards the separation surface of the front half. The suspension element preferably forms part of a second conveyor.
In a first preferred embodiment, the conveying directions of the first and the second conveyor are generally the same, the paths of the first and the second conveyor converging towards another.
In another preferred embodiment, the paths of the first and the second conveyor are generally parallel, and the first conveyor is arranged for operation at a lower speed in its conveying direction than that of the second conveyor in the same direction. In a further preferred embodiment, the paths of the first and the second conveyor are generally parallel, and the conveying directions of the first and the second conveyor are opposite. Here, the conical support element or any other suitable carrier picks up the front half because of the difference in speed between the first and second conveyor. This difference in speed ensures that the front half is pulled fast on the carrier, whereupon the front half is further fixed if desired and the back connection is broken by the forces exerted on it, or is broken in a controlled manner with the aid of a cutting element. The first or the second conveyor can be stationary when a front half is brought onto the carrier, while the other conveyor is in motion.
The claims and advantages will be more readily appreciated as the same becomes better understood by reference to the following detailed description and considered in connection with the accompanying drawings in which like reference symbols designate like parts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a shoulder joint of a bird, in which only one tendon is shown schematically;
FIGS. 2 and 3 schematically show in front and side views respectively, along a conveyor provided with carriers, a station for making a shoulder incision, a front half on a carrier being shown only in FIG. 2;
FIG. 4 shows a schematic side view of an embodiment of a filleting station according to the invention;
FIG. 4a schematically shows a cross-section of the apparatus shown in FIG. 4, taken on the line IVa--IVa.
FIG. 5 shows a schematic side view of an alternative embodiment of a station of the apparatus according to FIG. 4;
FIG. 6a shows in perspective a schematic view of a component of the apparatus shown in FIG. 4;
FIG. 6b is a schematic front view of a part of the carcass of a bird having inner fillets, to illustrate a first process;
FIG. 7 is a schematic view in perspective of the carcass part shown in FIG. 6b, to illustrate a second process;
FIG. 8 shows a schematic view in perspective of the carcass part shown in FIG. 6b, to illustrate a third process carried out thereon;
FIG. 9 shows a side view of a conveyor having a suspension hook on which a slaughtered, drawn bird is hung;
FIG. 10 illustrates a separation process to be carried out to separate the back half from the front half;
FIGS. 11a and 11b illustrate successive stages a first way of bringing a front half onto a carrier;
FIG. 12 illustrates a second way of bringing a front half on a carrier; and
FIG. 13a, 13b and 13c illustrate successive stages of removing the skin from a front half mounted on a carrier.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates the bone connections in the shoulder join and shows a part of the clavicle (wishbone) so, the coracoideum (collar bone) 82 with the processus acrocoracoideus 84 at one end, the scapula (shoulder blade) 86 and the humerus (wing bone) 88 with the caput humeri 90. The tendon connection between an inner fillet and the humerus 88 is represented by a broken line 91 and passes through the canalis triosseus 92. The canalis triosseus 92 is opened by cutting away the processus acrocoracoideus 84 from the coracoideum 82 along the dot-dash line 94, whereby the tendon connection 91 can come away from the canalis triosseus 92 and the inner fillet can be pulled free from the carcass by acting on the humerus 68.
FIGS. 2 and 3 show shoulder joint guides 98, humerus guides 100 and cutting elements 102. The shoulder joint guides 98, the humerus guides 100 and the cutting elements 102 are installed in a frame (not further shown) on both sides of the path of a conveyor by means of which carriers 104 can be moved along in the direction of the arrow 106. The cutting elements 102 are shown as rotating knives driven by a motor 108, but may also consist of fixedly mounted knives.
As illustrated in FIG. 2, on passing through the station the shoulder joints of a front half 110 placed on the carrier 104 are positioned by the should guides 98, which bear against that side of the processus acrocoracoideus 84 which faces away from the humerus 88. The humerus guides 100 ensure that the humerus is pressed downwards, after which the cutting elements 102 make the cut 94 (FIG. 1). IN a following processing station the inner fillets, optionally together with the outer fillets, can then be torn free from the carcass by means of (at least a part of) the humerus 88 or the wing. Before or directly after passing through the station shown in FIGS. 2 and 3, the clavicle 80 is optionally removed from the carcass in order to facilitate the tearing-off of the fillets from the carcass and thus to maximize the meat yield.
Another way to effect the filleting is discussed below with reference to FIGS. 4, 4a, 5, 6a, 6b, 7 and 8.
FIGS. 4 and 4a show two mirror-image conveyor rails 2a and 2b, between which are enclosed sliding elements 4 which can move in the longitudinal direction of the conveyor rails 2a,2b, in the direction indicated by the arrow 5. The sliding elements 4 are mutually coupled by means of a chain 3 or the like, indicated by a dot-dash line. A mounting support 6 is fastened rotatably and tiltably on each of the sliding elements 4. Each mounting support 6, which is described in greater detail i European Patent Application 551,156, has a substantially frustoconical end on which a front half 8 of a bird can be placed and fastened. For the sake of clarity only the rib cage 8a, the breastbone 8b,the clavicle 8c and the coracoideum 8d of each front half 8 are shown schematically in FIG. 4; the inner fillets, which are situated in the transition region between the rib cage 8a and the breastbone 8b are not shown in the figure in order to make it possible to show as clearly as possible the different components of the apparatus and the place where they act on the carcass.
Three processing stations 10, 20 and 30 respectively are installed along the path of the mounting supports 6. For the sake of clarity of the drawing the processing stations 10, 20 and 30 are as far as possible shown without support elements which affect the fixing of the processing station in relation to a frame in which the conveyor rails 2a and 2b are also held.
The processing station 10 is situated centrally above the conveyor rails 2a and 2b and comprises two guide strips 12, of which only one is visible in FIG. 4 and which between them leave open a slit of a width such that the upwardly projecting breast point of a front half 8 located on a mounting support 6 is guided therebetween. In the slit between the guide strips 12 is likewise situated an end of a pivotally mounted lever 14 which operates a switch 16 when the breast point of a front half 8 pushes the lever 14 out of the position shown in FIG. 4. The switch 16 thus gives a signal for the operation of the processing station 10, to which detailed reference will be made again further on. Above each guide strip 12 is situated a plate 19 provided with guide slots 18a and 18b. Between the plates 19 is enclosed a holder 21, which is shown in greater detail in FIG. 6a. The holder 21 is provided with pins 22a and 22b, which are guided in the slots 18a and 18b respectively. Outside the region of the plates 19, separating elements 24 are fastened resiliently on the holder 21. The separating elements 24 are each provided with two holes, which correspond with holes provided in the holder 21. Through the holes are pushed pins which are provided at each end of a plug 26 in order to enclose springs 28 between the plugs 26 and the separating elements 24, so that the latter can yield laterally. The edges of the separating elements 24 are usually made entirely blunt, but their front ends 24a may be provided with a cutting edge. The holder 21 is provided with a lip 32 or the like, to which an angle member 34 can be fastened. The end of the angle member 34 remote from the holder 21 is pivotally connected to the end of a piston rod 36 of a double-acting pneumatic cylinder and piston unit 38. At the end remote from the angle member 34 the cylinder and piston unit 38 is connected to the frame of the apparatus for pivoting about an axis 40.
the processing station 20 comprises two discs 42, which are installed one on each side of the path of the mounting supports 6, only one being visible in FIG. 4, and which are located at a distance from each other such that the breastbone 8b of a front half 8 mounted on a mounting support 6 can pas therebetween in the direction of the arrow 5. The discs 42 are mounted on axes 44, each of which during operation is driven in such a manner that the circumferential region of the discs 42 moves, near a front half 8 passing between them, in the direction of the arrow 5. The side of the discs 42 is frustoconical and stands at an angle of about 10° to the longitudinal direction of the axes 11. At one place on the circumference a radially projecting cutting element 46 is arranged on the bottom edge of each disc. The rotation of the discs 42 is synchronized with the movement of the mounting support 6 in the direction of the arrow 5.
The processing station 30 has guide strips 48 similarly to the processing station 10. Above the guide strips are installed guide walls 52 which are provided with guide slots 50a and 50b and between which, similarly to the processing station 10, a plate-shaped holder 56 provided with pins 54a and 54b is mounted so as to be slidable. Two scraping elements 58, of which the scraping front side is illustrated in greater detail in FIG. 8, are resiliently fastened to the holder 56. As shown in FIG. 8, the scrapers 58, which can be made of metal or plastics material, are installed at a short distance from each other and are provided on the front side with ends 58a bent sideways. The holder 52 is pivotally connected by means of an angle member 60 to the end of a piston rod 62 of double-acting pneumatic cylinder and piston unit 64. At the end remote from the angle member 60 the cylinder and piston unit 64 is pivotally connected to the frame of the apparatus.
The action of the apparatus will be explained with the aid of FIGS. 4, 6a, 6b, 7 and 8. In the first place, as shown in FIG. 4, a front half 8 fixed on a mounting support 6 is passed through the first processing station 10. Through the operation of the lever 14 by the breastbone 8b, the switch 16 signals the presence of a front half 8 on the mounting support 6, and delivers a signal to the control system of the apparatus so that, taking into account the speed of movement of the mounting support 6 in the direction of the arrow 5, after a predetermined delay time, the cylinder and piston unit 38 is energized. This energization takes place when the upwardly projecting point of the breastbone 8b of the front half 8 has passed the front side 24a of the separating elements 24. The holder 21 of the separating elements 24 is moved in the direction of the arrow 5 and slightly tilted downwards by means of the guide slots 18a when the piston rod 36 is pushed out of the cylinder and piston unit 38, the end position reached being shown in dashed lines in FIG. 4. The resulting movement of the separating elements 34 takes place very much more quickly than the movement of the mounting supports 6. The front sides 24a of the separating elements 24 thus move downwards along the breastbone and forwards into the openings bounded by the breastbone 8b and the clavicle 8c, releasing the membrane sternocoracoclavicularis. This is elucidated in FIG. 8b, in which arrows 68 illustrate the direction of the movement of the front sides 24a of the separating elements 24. Inner fillets 70 are thus cut free from the breastbone under the clavicle 8c. The separating elements 24 are then pulled back into the starting position shown in FIG. 4. It is to be remarked here that the clavicle may have been removed earlier from the front half, in which case the term clavicle in the above is merely used to define the natural position of the clavicle.
The front half, with the inner fillets 70 freed from the breastbone 8b under the clavicle 8c, then passes through the second processing station 20. The frustoconical side of the rotating discs 42 engages the sides of the inner fillets 70 and pushes them upwards, as illustrated by the arrows 72 in FIG. 7. In this action the cutting element 46 ensures that the membrane of the inner fillets 70 on the underside of the latter is cut free from the breastbone over some distance.
The preprocessed front half then passes through the third processing station 30, in which the guide strips 48 bring downwards again the inner fillets 70 pushed upward in the second processing station 20. After the upwardly projecting point of the breastbone 8b of a front half 8 has passed the ends 58a of the scraping elements 58 in the third processing station 30, the cylinder and piston unit 64 is energized. The moving piston rod 62 drives the holder 56 and the scraping elements 58 connected thereto in a movement, determined by the guide slots 50a and 50b, in the direction of the arrow 5, while the holder and the scraping elements 58 tilt slightly downwards. The end position reached is shown in dashed lines in FIG. 4. The movement of the scraping elements 58 takes place very much more quickly than the movement of the mounting supports 6. In the operative position the ends 58a of the scraping elements 58 come to lie one on each side of the clavicle 8c, as illustrated in FIG. 8, so that a movement of the front half 8 on the mounting support 6 in the direction of the arrow 5 results in a scraping force, exerted substantially in the direction of the arrows 74, on the inner fillets 70 on each side of the breastbone 8b.
FIG. 5 illustrates an alternative embodiment of a first processing station, in which a separation is made between the breastbone 8b and the inner fillets under the clavicle 8c. In a similar manner to that described with reference to FIG. 6a, separating means 24 are resiliently mounted on a lever 76 which is pivotable about a fulcrum 78. The end of the lever 76 remote from the separating elements 24 is pivotally connected to the end of the piston rod 36 of the cylinder and piston unit 38. When the piston rod 36 moves to the left in the drawing on the energization of the cylinder and piston unit 38, the lever 76 pivots in the counterclockwise direction and the front ends 24a of the separating elements 24 move along the breastbone 8b and under the clavicle 8c.
FIG. 9 shows a part of a rail 120 of substantially inverted T-shaped cross-section, along which suspension elements 122 are moved in the direction of the arrow 124. Further details of the suspension element 122 are not discussed here, since they are not relevant to the understanding of the present invention. The suspension element 122 carries a slaughtered, eviscerated bird 126, the breast side of which is turned in the conveying direction 124.
As illustrated in FIG. 10, in the separation of the carcass into a front half and a back half the bird 126 passes two substantially circular knives 130 which are rotatably mounted on axes 128 and which are arranged substantially in one plane at a predetermined distance from one another. The carcass is thus not completely cut through; connections remain intact under the breastbone and on the rear side between the front half 132 and the back half 134.
As shown in FIG. 11a, any skin connection under the breastbone gives way immediately because of the weight of the front half 132, whereas on the rear side of the carcass a connection 136 remains intact and is strong enough to carry the front half 132. A carrier 138, a conical end of which is directed towards the front half 132, is now brought into the path of the front half 132, and the carrier and the front half are moved towards one another, either by moving carrier 138 in the same direction 124 as the suspension element 122, but slower, or by moving carrier 138 in the opposite direction to direction 124. As illustrated in FIG. 11b,the front half 132 is so to speak "caught" on the carrier 138 and pulled fast on it. In this way the front half 132 comes completely automatically onto the carrier 138 and, after the connection 136 has been broken, said carrier can convey the front half 132 independently of the rear half to the previously described processing stations for the filleting of the front half 132.
As illustrated in FIG. 12, it is also possible to move the front half 132 and the carrier 138 side by side generally in the same direction at right angles to the plane of the drawing, bringing the front half 132 on the carrier 138 at a converging part of their paths, indicated by arrows 140.
FIG. 13a shows a front half 8 comprising wings 8w and skin and being mounted on the carrier 6 rotatably and tiltably mounted on the sliding element 4 moving in the direction of arrow 142. In the path of the carrier 6 with the front half 8 rotating knives 144 are arranged such that an incision 146 indicated with a dashed line is made in the skin between the upper side of each shoulder joint and each wing axilla. Following this, as illustrated in FIG. 13b, the carrier 6 is tilted into an upright position and brought in contact with rotating pairs of helically ribbed skin removal rollers 148, 150 (of which only one pair is visible in the drawing) for removing skin under the wings of the front half. To complete the fillet skin removal, as illustrated in FIG. 13c, the carrier 6 is tilted back into the position of FIG. 13a and brought in contact with a rotating pair of helically ribbed rollers 152 (of which only one is visible in the drawing) for removing the skin on the breast side of the front half.
While the invention has been described and illustrated in its preferred embodiments, it should be understood that departures may be made therefrom within the scope of the invention, which is not limited to the details disclosed herein. | This invention relates to both a method and an apparatus for placing slaughtered poultry on a carrier and a method and an apparatus for subsequently removing the skin from the slaughtered poultry on the carrier. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of priority from U.S. Provisional Application Ser. No. 61/531,707, filed Sep. 7, 2011, the entirety of which is expressly incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to providing access and a forum for allowing investment in companies, and, more particularly, to system and method for facilitating economic investments through social interactions.
SUMMARY OF THE INVENTION
[0003] The present invention may enable about 3-5 companies, per show/program, whether shown via the internet, podcast or other transfer medium, to pitch their company/idea/product/service to 3-5 popular national or local celebrities to endorse their products.
[0004] The present invention provides a computer-implemented system for generating product endorsements, comprising a non-transitory computer readable storage medium having encoded thereon computer executable instructions for providing a graphical user interface capable of querying at least one endorsement requester for the product information comprising at least product use information, target demographics information, and product origin information; a remote query engine capable of querying third party advisors on a network for product-related information related to a product indicated by the product information; at least one network port capable of remotely receiving via the network the product information from said graphical user interface, and the product-related information related to the product from the third-party advisors; at least one rules engine communicatively connected to said at least one network port, and comprising a plurality of rules to generate at least a tiered one of the product endorsements of a product responsively to the product information and the third party advisors information; and a reporting engine capable of providing local delivery to the endorsement requester of the tiered endorsements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The accompanying drawings are included to provide a further understanding of the disclosed embodiments. In the drawings:
[0006] FIG. 1 is a block diagram of an exemplary computing system for use in accordance with herein described systems and methods; and
[0007] FIG. 2 is a block diagram showing an exemplary networked computing environment for use in accordance with herein described systems and methods.
DETAILED DESCRIPTION
[0008] A computer-implemented platform and methods of use are disclosed that provide networked access to a plurality of types of digital content, including but not limited to video, audio, and document content, that may allow for social interaction with companies and ideas from those companies, such as via one or more applications, or “apps.” Described embodiments are intended to be exemplary and not limiting. As such, it is contemplated that the herein described systems and methods can be adapted to provide many types of users with access and delivery of many types of domain data, and can be extended to provide enhancements and/or additions to the exemplary services described. The invention is intended to include all such extensions. Reference will now be made in detail to various exemplary and illustrative embodiments of the present invention.
[0009] FIG. 1 depicts an exemplary computing system 100 that can be used in accordance with herein described system and methods. Computing system 100 is capable of executing software, such as an operating system (OS) and a variety of computing applications 190 . The operation of exemplary computing system 100 is controlled primarily by computer readable instructions, such as instructions stored in a computer readable storage medium, such as hard disk drive (HDD) 115 , optical disk (not shown) such as a CD or DVD, solid state drive (not shown) such as a USB “thumb drive,” or the like. Such instructions may be executed within central processing unit (CPU) 110 to cause computing system 100 to perform operations. In many known computer servers, workstations, personal computers, mobile devices, and the like, CPU 110 is implemented in an integrated circuit called a processor.
[0010] It is appreciated that, although exemplary computing system 100 is shown to comprise a single CPU 110 , such description is merely illustrative as computing system 100 may comprise a plurality of CPUs 110 . Additionally, computing system 100 may exploit the resources of remote CPUs (not shown), for example, through communications network 170 or some other data communications means.
[0011] In operation, CPU 110 fetches, decodes, and executes instructions from a computer readable storage medium such as HDD 115 . Such instructions can be included in software such as an operating system (OS), executable programs, and the like. Information, such as computer instructions and other computer readable data, is transferred between components of computing system 100 via the system's main data-transfer path. The main data-transfer path may use a system bus architecture 105 , although other computer architectures (not shown) can be used, such as architectures using serializers and deserializers and crossbar switches to communicate data between devices over serial communication paths. System bus 105 can include data lines for sending data, address lines for sending addresses, and control lines for sending interrupts and for operating the system bus. Some busses provide bus arbitration that regulates access to the bus by extension cards, controllers, and CPU 110 . Devices that attach to the busses and arbitrate access to the bus are called bus masters. Bus master support also allows multiprocessor configurations of the busses to be created by the addition of bus master adapters containing processors and support chips.
[0012] Memory devices coupled to system bus 105 can include random access memory (RAM) 125 and read only memory (ROM) 130 . Such memories include circuitry that allows information to be stored and retrieved. ROMs 130 generally contain stored data that cannot be modified. Data stored in RAM 125 can be read or changed by CPU 110 or other hardware devices. Access to RAM 125 and/or ROM 130 may be controlled by memory controller 120 . Memory controller 120 may provide an address translation function that translates virtual addresses into physical addresses as instructions are executed. Memory controller 120 may also provide a memory protection function that isolates processes within the system and isolates system processes from user processes. Thus, a program running in user mode can normally access only memory mapped by its own process virtual address space; it cannot access memory within another process' virtual address space unless memory sharing between the processes has been set up.
[0013] In addition, computing system 100 may contain peripheral controller 135 responsible for communicating instructions using a peripheral bus from CPU 110 to peripherals, such as printer 140 , keyboard 145 , and mouse 150 . An example of a peripheral bus is the Peripheral Component Interconnect (PCI) bus.
[0014] Display 160 , which is controlled by display controller 155 , can be used to display visual output generated by computing system 100 . Such visual output may include text, graphics, animated graphics, and/or video, for example. Display 160 may be implemented with a CRT-based video display, an LCD-based display, gas plasma-based display, touch-panel, or the like. Display controller 155 includes electronic components required to generate a video signal that is sent to display 160 .
[0015] Further, computing system 100 may contain network adapter 165 which may be used to couple computing system 100 to an external communication network 170 , which may include or provide access to the Internet, and hence which may provide or include tracking of and access to the domain data discussed herein. Communications network 170 may provide user access to computing system 100 with means of communicating and transferring software and information electronically, and may be coupled directly to computing system 100 , or indirectly to computing system 100 , such as via PSTN or cellular network 180 . For example, users may communicate with computing system 100 using communication means such as email, direct data connection, virtual private network (VPN), Skype or other online video conferencing services, or the like. Additionally, communications network 170 may provide for distributed processing, which involves several computers and the sharing of workloads or cooperative efforts in performing a task. It is appreciated that the network connections shown are exemplary and other means of establishing communications links between computing system 100 and remote users may be used.
[0016] It is appreciated that exemplary computing system 100 is merely illustrative of a computing environment in which the herein described systems and methods may operate and does not limit the implementation of the herein described systems and methods in computing environments having differing components and configurations, as the inventive concepts described herein may be implemented in various computing environments using various components and configurations.
[0017] As shown in FIG. 2 , computing system 100 can be deployed in networked computing environment 200 . In general, the above description for computing system 100 applies to server, client, and peer computers deployed in a networked environment, for example, server 205 , laptop computer 210 , and desktop computer 230 . FIG. 2 illustrates an exemplary illustrative networked computing environment 200 , with a server in communication with client computing and/or communicating devices via a communications network, in which the herein described apparatus and methods may be employed.
[0018] As shown in FIG. 2 , server 205 may be interconnected via a communications network 240 (which may include any of, or any combination of, a fixed-wire or wireless LAN, WAN, intranet, extranet, peer-to-peer network, virtual private network, the Internet, or other communications network such as POTS, ISDN, VoIP, PSTN, etc.) with a number of client computing/communication devices such as laptop computer 210 , wireless mobile telephone 215 , wired telephone 220 , personal digital assistant 225 , user desktop computer 230 , and/or other communication enabled devices (not shown). Server 205 can comprise dedicated servers operable to process and communicate data such as digital content 250 to and from client devices 210 , 215 , 220 , 225 , 230 , etc. using any of a number of known protocols, such as hypertext transfer protocol (HTTP), file transfer protocol (FTP), simple object access protocol (SOAP), wireless application protocol (WAP), or the like. Additionally, networked computing environment 200 can utilize various data security protocols such as secured socket layer (SSL), pretty good privacy (PGP), virtual private network (VPN) security, or the like. Each client device 210 , 215 , 220 , 225 , 230 , etc. can be equipped with an operating system operable to support one or more computing and/or communication applications, such as a web browser (not shown), email (not shown), or independently developed applications, the like, to interact with server 205 .
[0019] The server 205 may thus deliver applications specifically designed for mobile client devices, such as, for example, client device 225 . A client device 225 may be any mobile telephone, PDA, tablet or smart phone and may have any device compatible operating system. Such operating systems may include, for example, Symbian, RIM Blackberry OS, Android, Apple iOS, Windows Phone, Palm webOS, Maemo, bada, MeeGo, Brew OS, and Linux for smartphones and tablets. Although many mobile operating systems may be programmed in C++, some may be programmed in Java and .NET, for example. Some operating systems may or may not allow for the use of a proxy server and some may or may not have on-device encryption. Of course, because many of the aforementioned operating systems are proprietary, in prior art embodiments server 205 delivered to client device 225 only those applications and that content applicable to the operating system and platform communication relevant to that client device 225 type.
[0020] JavaScript Serialized Object Notation (JSON), a lightweight, text-based, language-independent data-interchange format, is based on a subset of the JavaScript Programming Language, Standard ECMA-262, 3.sup.rd Edition, dated December 1999. JSON syntax is a text format defined with a collection of name/value pairs and an ordered list of values. JSON is very useful for sending structured data over wire (e.g., the Internet) that is lightweight and easy to parse. It is language and platform independent, but uses conventions that are familiar to C-family programming conventions. The JSON language is thus compatible with a great many operating systems (a list of such systems is available at www.json.org).
[0021] In an embodiment of the present invention, a user may access the present invention through a GUI and participate in the funding of a participating company or individual, such as, for example, providing a start-up and/or series A invested companies with source and/or seed capital, angel capital, or other forms of direct investment.
[0022] The present invention may enable about 3-5 companies, per show/program, whether shown via the internet, podcast or other transfer medium, to pitch their company/idea/product/service to 3-5 popular national or local celebrities to endorse their products.
[0023] The present invention may provide access to personal advisers whom may test each product and service, and may have about 24-48 hours to maker a decision to endorse each product. Personal advisors, or other designated personnel, may only choose one or more companies, but each company may only have one personal advisor. For example, if all three stars want the same company, they must fight it out; and fans, or other participants who are interactively coupled to the present invention, may choose to select the best fit.
[0024] Such participants may call in, text, Tweet, or post via Facebook or other social medium, in their favorite company.
[0025] Participating companies may, before their sign up for “show”, may be required to agree to that if they are selected by one, or more celebrities, their must provide a percentage of equity in the company to the star; and star will sign a minimum of 1 year endorsement contract with each company. The company that WINS will get $250K marketing budget (which may be managed by a third party), and the selected star will get a percentage of equity, like, for example, a 10% stake and cash compensation, like, for example, $50,000.
[0026] Those of skill in the art will appreciate that the herein described systems and methods are susceptible to various modifications and alternative constructions. There is no intention to limit the scope of the invention to the specific constructions described herein. Rather, the herein described systems and methods are intended to cover all modifications, alternative constructions, and equivalents falling within the scope and spirit of the invention and its equivalents. | The present invention provides a computer-implemented system for generating product endorsements, comprising a graphical user interface capable of querying at least one endorsement requester for the product information comprising at least product use information, target demographics information, and product origin information; a remote query engine capable of querying third party advisors on a network for product-related information related to a product indicated by the product information; at least one network port capable of remotely receiving via the network the product information from said graphical user interface, and the product-related information related to the product from the third-party advisors; at least one rules engine communicatively connected to said at least one network port, and comprising a plurality of rules to generate at least a tiered one of the product endorsements of a product responsively to the product information and the third party advisors information. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a polymeric centralizer for centering pipe strings in well bores or within in other pipe strings which can be easily fitted onto a production string or casing during down hole insertion.
More particularly, the present invention relates to a polymeric centralizer for centralizing pipe strings in well bores and within in other pipe strings including a plurality of blades or fins extending substantially longitudinally along an outer surface of the centralizer, a slit through a blade opposite a groove for opening the centralizer so it can be fitted onto a production string or casing, a fastener means for securing or tightening the centralizer to the string or casing and cutaways for allowing wirelines or cables to pass between the centralizer and the production string to protect the cable, where the centralizer is wear and abrasion resistant, safe for use in hazardous environments and does not contribute to metal contamination of the well.
2. Description of the Related Art
In the completion of oil and gas wells it is standard practice to set or cement at least one string of casing within the well bore. Casing strings are cemented in the well bore to prevent fluids from migrating from the production zone through the annulus between the casing string and the well bore to the surface or other zones where for example fresh water may be contaminated. In addition, there are regulations which require that some zones be cemented off.
In cementing a casing string, a cement slurry is pumped down the interior of the casing string, out the lower end, into the annulus between the string and the well bore. However, to effect an efficient cementing job, the complete annulus needs to be cemented without pockets in the cement and without areas in which the string is contacting the wall of the well bore. To facilitate obtaining an effective cementing job the casing is commonly centered in the well bore with centralizers which are disposed about the casing string. In addition, the centralizers aide in running the pipe into the hole without hanging up.
Centralizers may also be used on casing or pipe strings, such as tubing, which are hung within another string of casing or pipe. These inner strings may be cemented within the outer pipe string or they may not be.
Centralizers for casing, tubing or pipe commonly are constructed of a low carbon steel having a tubular body or sleeve adapted to fit around a pipe joint. These prior art centralizers usually include outwardly bowed springs having opposing ends connected to opposite ends of the sleeve. Although the resiliency of the bow strings enables them to move through tight spots in the well bore, they may not support the weight of the casing string, especially in a highly deviated well bore.
In another type prior art centralizer, the bow strings are replaced by solid strips of metal which are tapered at each end to provide outer spaced bearing surfaces for engaging the well bore or the outer casing. Although less prone to collapse than bow springs under the weight of the casing string, these metal strips are often not strong enough to prevent bending upon contacting an obstruction or turn in the well bore. As a result, the centralizer and the casing may become wedged in the well, and, in any case become unsuitable for providing a suitable cementing job.
Another type of prior art centralizer is a non-metallic sleeve centralizer disclosed in U.S. Pat. No.; 5,908,072.
These prior art metal centralizers have further drawbacks, especially, when run and set within another string of pipe. One of the drawbacks of metal centralizer is contact with the outer pipe when the string vibrates. Metal to metal contact may cause a spark, which can be very hazardous in the hydrocarbon filled well. Also, metal centralizers can create a corrosion problem with the casing strings which it contacts through electrolysis. Metal centralizers also are susceptible to damage when running acid and circulating the acid back out of the hole. Additionally, there is a concern with scrapping the inner diameter of stainless steel tubing when running stainless/duplex stainless steel tubing having metal centralizers. The non-metallic sleeve centralizers overcome some of these disadvantages, but sleeve type centralizer are difficult to attach to pre-connected strings.
It would be a benefit, therefore, to have a polymeric centralizer adapted to fit about a string of pipe for centering the pipe in a well bore or within an outer string of pipe such as a production riser which can be easily attached to the string prior to or after make-up. It would be further benefit to have a polymer centralizer that can be used with downhole operations that require control cabling or umbilicals or wirelines where the cabling can be inserted through slots or cutaways in the centralizer.
SUMMARY OF THE INVENTION
The present invention provides a polymeric centralizer for centering a production string or casing within a well bore or within another string of casing or a riser including a plurality of fins or blades extending substantially longitudinally along an outer surface of the centralizer, a slit through a blade opposite a groove which cooperate to allow the centralizer to open so it can be fitted onto a production string or casing, a fastener means for securing the centralizer to the string or casing and cutaways for receiving and protecting wires, cables, umbilicals or other continuous cabling leading from the surface, where the centralizer has structural strength capable of withstanding the forces exerted by a string of pipe contacting a well bore or an outer string of pipe, is non-sparking when contacting metal pipe strings, does not promote electrolysis when in contact with a pipe string and provides cathodic protection between strings of pipe, is resistant to acid, is inexpensive to manufacture and is lightweight and has the tensile and compressive strength required to withstand the forces encountered in centralizing casing as opposed to the forces encountered by sucker rod guides and tube spacers. These centralizers are ideally suited for use with titanium risers attached to floating vessels where the centralizers centers and protects the inner surface of the riser from being damaged during the insertion of production strings.
The present invention also provides a drill or casing string and a plurality of centralizer fitted thereto for centering casing within a well bore or within another string of casing, where the centralizer includes a plurality of fins or blades extending longitudinally along an outer surface of the centralizer, a slit through a blade opposite a groove for opening the centralizer so it can be fitted onto a production string or casing, a fastener means for securing the centralizer to the string or casing and cutaways for allowing wirelines, electrical cables or other continuous cabling leading from the surface to a given distance below the surface.
The present invention provides a method for protecting a production string including the step of attaching to the string at regular or irregular intervals a plurality of centralizers of the present invention.
The present invention also provides a method for protecting a production string or casing including the steps of lowering a production string or casing into a well bore and attaching a polymeric centralizer of the present invention to the string or casing at intervals separated by a distance sufficient to prevent the production string or casing from contacting the well bore or inner pipe to reduce wear and tear and damage to the string or casing.
The present invention further provides a method for fitting a centralizer to a production string or casing including the step of opening the centralizer at a slit through a blade opposite a groove, forcing the opened centralizer over the production string or casing and tightening a fastener to draw the slit tight together and secure the centralizer to the string or casing.
Preferably, the blades have a bearing surface for bearing against a well bore or an outer casing in which the string or casing carrying the centralizer is disposed. The blades extend outwardly from the centralizer to space the carrying string from the well bore or outer casing string.
It is also preferred that the blades have opposing ends tapered outwardly toward one another. However, it is not necessary that the blade ends be tapered. It may also be desired to have the blades sweep at an angle as they extend longitudinally down the sleeve.
The polymeric centralizer may be positioned on the pipe and allowed to float between the collars at adjacent casing joint connections. The centralizer may be connected to the casing joint by an adhesive. The centralizer may be connected to the casing joint by set screw which are adjustably disposed through the centralizer so as to engage the casing joint. The centralizer may be connected to joint and cable protectors such as coupling protectors made by Cannon Services, Inc. of Missouri City, Tex. and described U.S. Pat. No. 4,615,543, incorporated herein by reference. The centralizer may be fixedly connected to the casing joint via stop collars or rings connected to the casing string adjacent opposing ends of the centralizer. The stop rings may be of any type well known in the art such as the Frank's SB stop ring.
Additionally, the stop rings may be constructed of the same or similar polymeric as the centralizers of this invention. Preferably, a stop collar formed of the same or substantially same polymeric material as the centralizer would include an outer ring, an inner ring positioned between the outer ring and the casing joint to be engaged and having an inner face for gripping the casing joint, and an activating mechanism for securing the inner ring to the outer ring and facilitate engagement with the casing joint.
DESCRIPTION OF THE DRAWINGS
The invention can be better understood with reference to the following detailed description together with the appended illustrative drawings in which like elements are numbered the same:
FIG. 1 is a top view of one embodiment of a polymeric centralizer of this invention;
FIG. 2 is a first side view of the centralizer of FIG. 1 showing the groove;
FIG. 3 is a second side view of the centralizer of FIG. 1 showing the fastener;
FIG. 4 shows the centralizer of FIG. 1 in its opened state for fitting over a pipe;
FIG. 5 is a top view of another embodiment of a polymeric centralizer of this invention;
FIG. 6 is a top view of another embodiment of a polymeric centralizer of this invention;
FIG. 7 is a top view of another embodiment of a polymeric centralizer of this invention;
FIG. 8 is a front view of the centralizer of FIG. 1 secured to a pipe; and
FIG. 9 is a perspective view of two centralizer of FIG. 1 secured to a section of a string including a joint and a joint protector showing cabling extending along the string.
DETAILED DESCRIPTION OF THE INVENTION
The inventors have found that a polymeric centralizer can be constructed for use on production string or casing where the centralizer includes a slit through a blade opposite a groove or thin portion of the centralizer for opening the centralizer and fitting the centralizer over the string or casing with cutaways to protect surface cabling extending along a length of the string. Such a centralizer is ideally suited for use downhole operations such as drilling, completion, testing or the like.
The present invention broadly relates to a centralizer including a plurality of longitudinally extending blades or fins, a slit through a blade opposite groove for opening the centralizer so it can be fitted onto a production string or casing string or production riser and a fastener for bringing the slit together and tightening the centralizer onto the string or casing. Preferably, the centralizer also includes an inner cutaway or plurality of cutaways to accommodate cabling or wires extending from the surface down the length of the string.
The present invention also broadly relates to a method for protecting and centering a production string in a well bore or outer casing or production riser including attaching a plurality of centralizers of the present invention at intervals along the string to keep the string centered in the well bore or outer casing or riser and protected from contacting the well bore or outer casing or riser.
The present invention also broadly relates to a method for protecting cabling and centering a production string in a well bore or outer casing or production riser including attaching a plurality of centralizers of the present invention at intervals along the string to keep the string centered in the well bore or outer casing or riser and protected from contacting the well bore or outer casing or riser and running cabling through the cutaways in the centralizer.
The present invention also relates to a production string comprising sections of piping joined at joints each joint fitted with a joint protector and a plurality of centralizers of this invention fitted onto the string at space apart intervals sufficient to maintain the string substantially in the center of the well bore or inside an outer tubing or riser and a cable extending from the surface and running through the joint protectors and centralizer cutaways where the joint protectors and centralizers act to protect the cable as the string is inserted into or removed from the well bore or outer tubing.
The present invention also relates to a method for protecting a production string of tubing including the steps of opening a plurality of centralizer of this invention at each slit, pushing the centralizer over the tubing a spaced apart intervals sufficient to substantially center the string in a well bore or outer tubing and securing the centralizer onto the tubing at the intervals by tightening the fasteners.
The present invention also relates to a method for protecting a cable accompanying string of production tubing including the steps of attaching a joint protector to each joint in the string, attaching a plurality of centralizer of this invention to the string at spaced apart intervals sufficient to substantially center the string in a well bore or outer tubing or riser and threading the cabling through the protectors and the centralizers to protect the cable during insert into and removal from the well bore or outer tubing.
Suitable polymers for making the centralizers of the present invention include, without limitation, an engineering thermoplastic such as an acetal resins e.g., Delrin® from DuPont or other similar injection moldable polymers. The polymers should have a tensile strength between about 8,000 psi and about 14,000 psi at 73° F., a Tensile modulus of elasticity at 73 ° F. between about 400,000 psi and about 550,000 psi, an elongation of about at 73 ° F. between about 30% and 60%, a flexural strength at 73° F. between about 13,000 psi and about 16,000 psi, a flexural modulus of elasticity at 73° F. between about 350,000 psi and about 600,000 psi, a shear strength at 73° F. between about 7,000 psi to about 10,000 psi, a compressive strength at 10% deformation between about 15,000 psi and about 20,000 psi, dynamic coefficient of friction 0.25, Rockwell hardness at 73° F. between about 115 to about 125, coefficient of linear thermal expansion between about 5×10 −4 and about 7×10 −4 in/in/° F., deformation under load (122° F. and 2,000 psi) of about 0.7 to about 1.1%, deflection temperature at 264 psi between about 225 and about 260° F., melting point of crystalline part of composition between about 325 and about 350° F., continuous service temperature in air (max) of about 180° F., dielectric strength short time between about 350 and about 550 V/nul, volume resistivity between about 1×10 13 and about 1×10 16 OHM·cm, dielectric constant at 60Hz of about 3.7, dielectric constant at 10 5 Hz of about 3.7, dielectric constant at 10 6 Hz of about 3.7, and acceptable water, acid, base and solvent resistance. The thermoplastic is generally mixed with other ingredients to improve physical properties and lifetime such as fillers, antidegradants, or other common additives. The preferred thermoplastic composition is Celleprin 60 available for BJ Molding of Houston.
The centralizers of this invention are ideally suited for tubing having a dimension between about 3″ and about 6″, although centralizers can be fabricated for any other diameter tubing. The body thickness for 3.5″ id is between about 0.75″ and about 1.5″, preferably between about 1″ and about 1.5″ and particularly between about 1″ and about 1.25″. The blade thickness from the body is between about 0.75″ and about 1.25″ and preferably between about 1″ and about 1.2″. The distance between blades on the body is between about 1.2″ and about 1.4″, but the blades separation near the groove is slightly smaller. For a 3.5 i.d., the o.d. of the centralizer profile is between about 7.75″ and about 8.5″, but a larger and smaller o.d. is a matter of design choice. The groove depth should be sufficient to allow the centralizer to be opened at the slit through a blade opposite the groove, but not so deep that the centralizer is significantly weakened at the interior of the groove. If the body is about 1.25″ thick, then the groove depth is between about 0.6″ and 0.85″, but the depth is more a design consideration.
The present invention is more fully described in reference to the following Figures and their description which are presented for illustration and not for limitation. It should be recognized that the implementation represented by the Figures is only one implementation of many that would function equivalently.
Referring now to FIGS. 1 to 3 , one embodiment of a centralizer, generally 100 , of the present invention is shown to include a body 102 , a plurality of blades 104 extending longitudinally along a length of the body 102 , a slit 106 through the blade 105 opposite a groove 108 and oppositely disposed holes 110 for receiving fasteners 112 shown here as nuts and bolts, but any fastener means can be used as well. The centralizer 100 also includes a plurality of arcuate cutaways 114 for receiving and protecting cabling extending from the surface along a length of a string of pipe onto which the centralizer 100 is fitted. The slit 106 and the groove 108 are designed so that the centralizer 100 can be put in an opened condition for fitting over a pipe as shown in FIG. 4 .
Referring now to FIG. 5, another embodiment of a centralizer, generally 120 , of the present invention is shown to include a body 122 , a plurality of blades 124 extending longitudinally along a length of the body 122 , a slit 126 through the blade 125 opposite a groove 128 and oppositely disposed holes 130 for receiving fasteners 132 shown here as nuts and bolts, but any fastener means can be used as well. The centralizer 120 also includes a channel cutaway 134 for receiving and protecting cabling extending from the surface along a length of a string of pipe onto which the centralizer 120 is fitted.
Referring now to FIG. 6, another embodiment of a centralizer, generally 140 , of the present invention is shown to include a body 142 , a plurality of blades 144 extending longitudinally along a length of the body 142 , a slit 146 through the blade 145 opposite a groove 148 and oppositely disposed holes 150 for receiving fasteners 152 shown here as nuts and bolts, but any fastener means can be used as well. The centralizer 140 also includes holes 154 for receiving and protecting cabling extending from the surface along a length of a string of pipe onto which the centralizer 140 is fitted.
Referring now to FIG. 7, another embodiment of a centralizer, generally 160 , of the present invention is shown to include a body 162 , a plurality of blades 164 extending longitudinally along a length of the body 162 , a slit 166 through the blade 165 opposite a groove 168 and oppositely disposed holes 170 for receiving fasteners 172 shown here as nuts and bolts, but any fastener means can be used as well. The centralizer 160 also includes a slot 174 for receiving and protecting cabling extending from the surface along a length of a string of pipe onto which the centralizer 160 is fitted.
Referring now to FIG. 8, a centralizer 100 of FIG. 1 secured to a section of pipe 180 by nuts and bolts 182 .
Referring now to FIG. 9, a plurality of centralizers 100 of FIG. 1 positioned at intervals 190 along a pipe string 192 including a joint 194 protected by a joint protector 196 and a cable 198 running along the string 192 through one of the cutaways 114 and into and through the joint protector 196 .
It can be seen from the preceding description that a polymeric centralizer for centering a string of pipe within a well bore or another string of pipe which provides ease of attachment after string make-up having a slit through a blade and oppositely disposed groove and structural strength capable of withstanding the forces exerted by a string of pipe contacting a well bore or an outer string of pipe, is non-sparking when contacting metal pipe strings, does not promote electrolysis when in contact with a pipe string and provides cathodic protection between strings of pipe, and is resistant to acid has been provided.
All references cited herein are incorporated by reference. While this invention has been described fully and completely, it should be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. Although the invention has been disclosed with reference to its preferred embodiments, from reading this description those of skill in the art may appreciate changes and modification that may be made which do not depart from the scope and spirit of the invention as described above and claimed hereafter. | A polymeric centralizer for casing having a body adapted to fit closely about the casing, a plurality of blades extending substantially longitudinally along an outer surface of body, a slit through a blade and opposing groove to allow the centralizer to be spread apart and a fastener to pulling the slit together and tightening the centralizer about the casing. The polymeric centralizer having strength characteristics capable of withstanding the forces encountered in casing operations. The polymeric centralizer is non-sparking for use in hazardous environments, abrasion and wear resistant, and provides protection from electrolysis between adjacent casing strings. The polymeric centralizer is light weight, allowing increased transportation capacity at a economical cost and allows easy attachment to broken down or made-up piping, production string or casing and including hole or cutaways for receiving surface cabling. | 4 |
RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 61/605,300, filed Mar. 1, 2012, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to novel benzofuran-2-sulfonamide derivatives, processes for preparing them, pharmaceutical compositions containing them and their use as pharmaceuticals as modulators of chemokine receptors. The invention relates specifically to the use of these compounds and their pharmaceutical compositions to treat disorders associated with chemokine receptor modulation.
BACKGROUND OF THE INVENTION
[0003] Chemokines are a group of 7- to 14-kd peptides that play an important role in orchestrating leukocyte recruitment and migration during inflammation, and therefore represent an important target for anti-inflammatory therapies (Wells et al., 2006). They act by binding to seven-transmembrane, G protein-coupled receptors, the chemokine receptors. The chemokine system is complex, with about 50 chemokines and 20 chemokine receptors identified in humans, often acting with redundancy, making selection of specific antagonists difficult (Gerard and Rollins, 2001). Genetic knockout strategies have confirmed the importance of chemokines as regulators of immune function, but the deletion of specific chemokines has led to only specific and relatively mild defects in the inflammatory response further emphasizing the complex redundancy of the system. Selectivity is crucial for use of chemokine receptor antagonists in systemic diseases where a single chemokine-receptor system is implicated such as atheroscelorsis where the macrophage/monocyte system is the major player in order to allow a subtle and specific control over immune function (Weisberg et al., 2006; Feria and Diaz Gonzalez et al., 2006).
[0004] Many ocular conditions are characterized by inappropriate migration and infiltration of cells such as leukocytes and endothelial cells into the eye with deleterious effects to ocular structures (Wallace et al., 2004). Chemokines have been identified in such diseases and misregulation of the chemokine system is apparent in corneal graft rejection, diabetic retinopathy, age-related macular degeneration (ARMD), chronic inflammatory diseases such as uveitis, dry eye etc. Mice lacking CCR2 or MCP-1 develop features of ARMD with age, including drusen deposits, choroidal neovascularization and photoreceptor atrophy indicating a crucial role for this chemokine and its receptor signaling (Amabati et al., 2003). Thus CCR2 receptor-specific inhibitor might have potential therapeutic benefit in ocular diseases like ARMD. In contrast, various human and animal studies have identified several chemokines in different forms of uveitis, produced both by resident and infiltrating cells, that strongly suggests a prominent role for these molecules in its pathogenesis. Studies in rat and mice models of uveitis have demonstrated up-regulation of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1 (MIP-1), RANTES, stromal derived factor-1 (SDF-1) which are powerful chemoattractants for monocytes and T-cells (Fang et al., 2004; Keino et al., 2003). Similar findings have been reported in peripheral blood mononuclear cells in patients with acute anterior uveitis (AAU), the most common form of human uveitis (Klitgaard et al., 2004). MCP-1 knockout mice and CCR5 knockout mice show reduced endotoxin-induced uveitis, which is the animal model for AAU (Takeuchi et al., 2005; Tuallion et al., 2002). It has also been demonstrated that blocking the chemokine system upstream with the use of NF-κB blockers significantly attenuates experimental AAU in rats (Yang et al., 2005). Blockage of NF-κB results in transcriptional inhibition of multiple chemokines. Given the complexity of pathogenesis in uveitis it is unlikely that a selective inhibition of a chemokine receptor in monotherapy will offer therapeutic benefit. A similar role of multiple chemokines have been shown to be correlated with clinical stage of disease in diabetic retinopathy and dry eye (Meleth et al., 2005; Yamagami et al., 2005). In these ocular diseases the use of broad spectrum chemokine receptor inhibitor which inhibits the function of a wide range of chemokines may be beneficial.
[0005] The first broad spectrum chemokine inhibitor (BSCI) to be reported was termed Peptide 3, which was derived from the sequence of human chemokine MCP-1 and was shown to block the migration of monocytes in response to MCP-1, MIP-1, RANTES and SDF-1 (Reckless and Grainger. 1999). A cyclic retro inverse analogue of Peptide 3, constructed of D-amino acids in the reverse sequence, called NR58-3.14.3 was observed to be a more potent chemokine inhibitor (Beech et al., 2001). NR58-3.14.3 has been used to test for anti-inflammatory activities in animal models of atherosclerosis, lung inflammation, irritable bowel syndrome etc (Beech et al., 2001; Grainger and Reckless. 2003; Tokuyama et al., 2005). However there are several disadvantages to using these BSCI as a long-term therapeutic strategy. The known BSCIs which are peptides which have relatively low potency, poor pharmacokinetics, and are unstable in vivo. In addition, systemic use of broad spectrum chemokine receptor inhibitors could potentially lead to deleterious side effects due to their systemic anti-inflammatory activity. However in ocular diseases, a local or topical application would prevent the broad spectrum inhibitor to be taken up systemically. Identification of a small molecule inhibitor of several chemokine receptors could be very useful for treatment of inflammatory ocular diseases. Given the evidence for the role of multiple chemokines in several ocular diseases and these results, we propose that the use of small and large molecule broad spectrum chemokine receptor inhibitors will have utility in the local treatment of ocular inflammatory diseases including, but not limited to, uveitis, dry eye, diabetic retinopathy, allergic eye disease and proliferative retinopathies. Manipulation of multiple chemokines therefore represents a novel therapeutic approach in treating ocular diseases.
[0006] WO2008008374 discloses CCR2 inhibitors and methods of use thereof.
[0007] WO03/099773 discloses CCR9 inhibitors and methods of use thereof.
[0008] US2012014997 discloses CCR9 inhibitors and methods of use thereof.
[0009] U.S. Pat. No. 7,622,583 discloses heteroaryl sulfonamides as antagonists of the CCR2 receptor.
[0010] US20110118248 discloses heteroaryl sulfonamides as antagonists of the CCR2 receptor.
[0011] U.S. Pat. No. 7,884,110 discloses CCR2 inhibitors and methods of use thereof.
[0012] US 2008/0293720 discloses pyridinyl sulfonamide modulators of chemokine receptors.
[0013] U.S. Pat. No. 7,393,873 discloses arylsulfonamide derivatives.
SUMMARY OF THE INVENTION
[0014] A group of novel benzofuran-2-sulfonamide derivatives which are potent and selective chemokine receptor modulators, has been now discovered. As such, the compounds described herein are useful in treating a wide variety of disorders associated with modulation of chemokine receptors. The term “modulator” as used herein, includes but is not limited to: receptor agonist, antagonist, inverse agonist, inverse antagonist, partial agonist, partial antagonist.
[0015] This invention describes compounds of Formula I, which have chemokine receptor biological activity. The compounds in accordance with the present invention are thus of use in medicine, for example in the treatment of humans with diseases and conditions that are alleviated by chemokine receptor modulation.
[0016] In one aspect, the invention provides a compound having Formula I or a pharmaceutically acceptable salt thereof or stereoisomeric forms thereof, or the individual geometrical isomers, enantiomers, diastereoisomers, tautomers, zwitterions and pharmaceutically acceptable salts thereof:
[0000]
[0000] wherein:
R 1 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 2 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 3 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 4 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 5 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 6 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 7 is halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 8 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 9 is O, C(O), S, S(O), S(O) 2 , or —C(═NOR 16 )—; a is 0 or 1; R 11 is CN, substituted or unsubstituted C 1-6 alkyl, CF 3 , OR 12 , NR 13 R 14 , substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 3-8 cycloalkyl, substituted or unsubstituted C 2-6 alkyne, substituted or unsubstituted C 2-6 alkene or COR 15 ; R 12 is hydrogen or substituted or unsubstituted C 1-6 alkyl; R 13 is hydrogen or substituted or unsubstituted C 1-6 alkyl or can form an optionally substituted heterocycle with R 14 ; R 14 is hydrogen, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 6-10 aryl or can form an optionally substituted heterocycle with R 13 ; R 15 is hydrogen, hydroxyl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 1-6 alkyl; R 16 is hydrogen or substituted or unsubstituted C 1-6 alkyl; X is CR 17 ; R 17 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl; with the provisos: a) when R 9 is S, S(O) or S(O) 2 then R 11 is substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, or substituted or unsubstituted C 3-8 cycloalkyl; and the compound of Formula I is not of structure:
[0000]
[0039] In another aspect the invention provides a compound having Formula I wherein:
R 1 is hydrogen; R 2 is hydrogen; R 3 is hydrogen; R 4 is hydrogen; R 5 is hydrogen; R 6 is hydrogen, halogen, CN, substituted or unsubstituted C 1-8 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 7 is halogen, CN, substituted or unsubstituted C 1-8 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 8 is hydrogen, halogen, CN, substituted or unsubstituted C 1-8 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 9 is S, S(O) or S(O) 2 ; a is 1; R 11 is substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 3-8 cycloalkyl; R 12 is hydrogen or substituted or unsubstituted C 1-8 alkyl; R 13 is hydrogen or substituted or unsubstituted C 1-8 alkyl; R 14 is hydrogen, substituted or unsubstituted C 1-8 alkyl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 8-10 aryl; R 15 is hydrogen, hydroxyl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 1-6 alkyl; R 16 is hydrogen or substituted or unsubstituted C 1-6 alkyl; X is CR 17 ; R 17 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl.
[0059] In another aspect the invention provides a compound having Formula I wherein:
R 1 is hydrogen; R 2 is hydrogen; R 3 is hydrogen; R 4 is hydrogen; R 5 is hydrogen; R 6 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 7 is halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 8 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 9 is O or C(O); a is 1; R 11 is CN, substituted or unsubstituted C 1-6 alkyl, CF 3 , OR 12 , NR 13 R 14 , substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 3-8 cycloalkyl, substituted or unsubstituted C 2-6 alkyne, substituted or unsubstituted C 2-6 alkene or COR 15 ; R 12 is hydrogen or substituted or unsubstituted C 1-6 alkyl; R 13 is hydrogen or substituted or unsubstituted C 1-6 alkyl or can form an optionally substituted heterocycle with R 14 ; R 14 is hydrogen, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 6-10 aryl or can form an optionally substituted heterocycle with R 13 ; R 15 is hydrogen, hydroxyl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 1-6 alkyl; R 16 is hydrogen or substituted or unsubstituted C 1-6 alkyl; X is CR 17 ; R 17 is hydrogen, halogen, CN, substituted or unsubstituted C 1-6 alkyl, OR 12 , NR 13 R 14 , or COR 15 ; R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl.
[0079] In another aspect the invention provides a compound having Formula I wherein:
R 1 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 2 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 3 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 4 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 5 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 6 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 7 is halogen or substituted or unsubstituted C 1-6 alkyl; R 8 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 9 is S, S(O) or S(O) 2 a is 1; R 11 is substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 3-8 cycloalkyl; X is CR 17 ; R 17 is hydrogen; and R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl.
[0094] In another aspect the invention provides a compound having Formula I wherein:
R 1 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 2 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 3 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 4 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 5 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 6 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 7 is halogen or substituted or unsubstituted C 1-6 alkyl; R 8 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 9 is O; a is 1; R 11 is CN, substituted or unsubstituted C 1-6 alkyl, CF 3 , OR 12 , NR 13 R 14 , substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 3-8 cycloalkyl, substituted or unsubstituted C 2-6 alkyne, substituted or unsubstituted C 2-6 alkene or COR 15 ; R 12 is hydrogen or substituted or unsubstituted C 1-6 alkyl; R 13 is hydrogen or substituted or unsubstituted C 1-6 alkyl or can form an optionally substituted heterocycle with R 14 ; R 14 is hydrogen, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 6-10 aryl or can form an optionally substituted heterocycle with R 13 ; R 15 is hydrogen, hydroxyl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 1-6 alkyl; X is CR 17 ; R 17 is hydrogen; and R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl.
[0113] In another aspect the invention provides a compound having Formula I wherein:
R 1 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 2 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 3 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 4 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 5 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 6 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 7 is halogen; R 8 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 9 is C(O); a is 1; R 11 is CN, substituted or unsubstituted C 1-6 alkyl, CF 3 , OR 12 , NR 13 R 14 , substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 3-8 cycloalkyl, substituted or unsubstituted C 2-6 alkyne, substituted or unsubstituted C 2-6 alkene or COR 15 ; R 12 is hydrogen or substituted or unsubstituted C 1-6 alkyl; R 13 is hydrogen or substituted or unsubstituted C 1-6 alkyl or can form an optionally substituted heterocycle with R 14 ; R 14 is hydrogen, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 6-10 aryl or can form an optionally substituted heterocycle with R 13 ; R 15 is hydrogen, hydroxyl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 1-6 alkyl; X is CR 17 ; R 17 is hydrogen; and R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl.
[0132] In another aspect the invention provides a compound having Formula I wherein:
R 1 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 2 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 3 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 4 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 5 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 6 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 7 is halogen; R 8 is hydrogen, halogen or substituted or unsubstituted C 1-6 alkyl; R 9 is —C(═NOR 16 )—; a is 1; R 11 is CN, substituted or unsubstituted C 1-6 alkyl, CF 3 , OR 12 , NR 13 R 14 , substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 3-8 cycloalkyl, substituted or unsubstituted C 2-6 alkyne, substituted or unsubstituted C 2-6 alkene or COR 15 ; R 12 is hydrogen or substituted or unsubstituted C 1-6 alkyl; R 13 is hydrogen or substituted or unsubstituted C 1-6 alkyl or can form an optionally substituted heterocycle with R 14 ; R 14 is hydrogen, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted heterocycle or substituted or unsubstituted C 6-10 aryl or can form an optionally substituted heterocycle with R 13 ; R 15 is hydrogen, hydroxyl, substituted or unsubstituted heterocycle, substituted or unsubstituted C 6-10 aryl or substituted or unsubstituted C 1-6 alkyl; R 16 is hydrogen or substituted or unsubstituted C 1-6 alkyl; X is CR 17 ; R 17 is hydrogen; and R 18 is hydrogen or substituted or unsubstituted C 1-6 alkyl.
[0152] The term “alkyl”, as used herein, refers to saturated, monovalent or divalent hydrocarbon moieties having linear or branched moieties or combinations thereof and containing 1 to 6 carbon atoms. One methylene (—CH 2 —) group, of the alkyl can be replaced by oxygen, sulfur, sulfoxide, nitrogen, carbonyl, carboxyl, sulfonyl, or by a divalent C 3-6 cycloalkyl. Hydrogen atoms on alkyl groups can be substituted by groups including, but not limited to: halogens, —OH, C 3-8 cycloalkyl, non-aromatic heterocycles, aromatic heterocycles, —OC 1-6 alkyl, —NH 2 , —NO 2 , amides, carboxylic acids, ketones, ethers, esters, aldehydes, or sulfonamides.
[0153] The term “cycloalkyl”, as used herein, refers to a monovalent or divalent group of 3 to 8 carbon atoms, derived from a saturated cyclic hydrocarbon. Cycloalkyl groups can be monocyclic or polycyclic. Cycloalkyl can be substituted by groups including, but not limited to: halogens, —OH, C 3-8 cycloalkyl, non-aromatic heterocycles, aromatic heterocycles, —OC 1-6 alkyl, —NH 2 , —NO 2 , amides, ethers, esters, carboxylic acids, aldehydes, ketones, or sulfonamides.
[0154] The term “cycloalkenyl”, as used herein, refers to a monovalent or divalent group of 3 to 8 carbon atoms, derived from a saturated cycloalkyl having one or more double bonds. Cycloalkenyl groups can be monocyclic or polycyclic. Cycloalkenyl groups can be substituted by groups including, but not limited to: halogens, —OH, C 3-8 cycloalkyl, non-aromatic heterocycles, aromatic heterocycles, —OC 1-6 alkyl, —NH 2 , —NO 2 , amides, ethers, esters, aldehydes, ketones, carboxylic acids, sulfonamides groups.
[0155] The term “halogen”, as used herein, refers to an atom of chlorine, bromine, fluorine, iodine.
[0156] The term “alkenyl”, as used herein, refers to a monovalent or divalent hydrocarbon radical having 2 to 6 carbon atoms, derived from a saturated alkyl, having at least one double bond. C 2-6 alkenyl can be in the E or Z configuration. Alkenyl groups can be substituted by C 1-6 alkyl.
[0157] The term “alkynyl”, as used herein, refers to a monovalent or divalent hydrocarbon radical having 2 to 6 carbon atoms, derived from a saturated alkyl, having at least one triple bond.
[0158] The term “heterocycle” as used herein, refers to a 3 to 10 membered ring, which can be aromatic or non-aromatic, saturated or unsaturated, containing at least one heteroatom selected from O or N or S or combinations of at least two thereof, interrupting the carbocyclic ring structure. The heterocyclic ring can be interrupted by a C═O; the S heteroatom can be oxidized. Heterocycles can be monocyclic or polycyclic. Heterocyclic ring moieties can be substituted by groups including, but not limited to: halogens, —OH, C 3-8 cycloalkyl, non-aromatic heterocycles, aromatic heterocycles, —OC 1-6 alkyl, —NH 2 , —NO 2 , amides, ethers, esters, aldehydes, carboxylic acids, ketones, sulfonamides groups.
[0159] The term “aryl” as used herein, refers to an organic moiety derived from an aromatic hydrocarbon consisting of a ring containing 6 to 10 carbon atoms by removal of one hydrogen. Aryl can be monocyclic or polycyclic. Aryl can be substituted by groups including, but not limited to: halogens, —OH, C 3-8 cycloalkyl, non-aromatic heterocycles, aromatic heterocycles, —OC 1-6 alkyl, —NH 2 , —NO 2 , amides, ethers, esters, carboxylic acids, ketones, aldehydes, sulfonamides groups.
[0160] The term “amide” as used herein, represents a group of formula “—C(O)NR x R y ” or wherein R x and R y are the same or independently H or C 1-6 alkyl.
[0161] The term “ketone” as used herein, represents a group of formula “—C(O)R x ” wherein R x is C 1-6 alkyl.
[0162] The term “ester” as used herein, represents a group of formula “—C(O)OR x ” wherein R x is C 1-6 alkyl.
[0163] The term “ether” as used herein, represents a group of formula “—OR x ” wherein R x is C 1-6 alkyl.
[0164] The term “aldehyde” as used herein, represents a group of formula “—C(O)H”.
[0165] The term “sulfonamide” as used herein, represents a group of formula “—S(O) 2 NR x R y ” wherein R x and R y are the same or independently H or C 1-6 alkyl.
[0166] The term “hydroxyl” as used herein, represents a group of formula “—OH”.
[0167] The term “amino” as used herein, represents a group of formula “—NH 2 ”.
[0168] The term “carbonyl” as used herein, represents a group of formula “—C(O)—”.
[0169] The term “carboxyl” as used herein, represents a group of formula “—C(O)O—”.
[0170] The term “sulfonyl” or the term “sulfone” as used herein, represents a group of formula “—SO 2 —”.
[0171] The term “sulfate” as used herein, represents a group of formula “—O—S(O) 2 —O—”.
[0172] The term “carboxylic acid” as used herein, represents a group of formula “—C(O)ON”.
[0173] The term “sulfoxide” as used herein, represents a group of formula “—S(O)—”.
[0174] The term “phosphonic acid” as used herein, represents a group of formula “—P(O)(OH) 2 ”.
[0175] The term “phosphoric acid” as used herein, represents a group of formula “—O—P(O)(OH) 2 ”.
[0176] The term “sulphonic acid” as used herein, represents a group of formula “—S(O) 2 OH”.
[0177] The formula “H”, as used herein, represents a hydrogen atom.
[0178] The formula “O”, as used herein, represents an oxygen atom.
[0179] The formula “N”, as used herein, represents a nitrogen atom.
[0180] The formula “S”, as used herein, represents a sulfur atom
[0181] Compounds of the invention are:
N-(5-chloro-2-methoxyphenyl)-1-benzofuran-2-sulfonamide; N-(5-chloro-2-methylphenyl)-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(trifluoromethoxy)phenyl]-1-benzofuran-2-sulfonamide; methyl 2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorobenzoate; N-(5-chloro-2-ethoxyphenyl)-1-benzofuran-2-sulfonamide; N-(5-chloro-2-ethynylphenyl)-1-benzofuran-2-sulfonamide; N-{5-chloro-2-[(4-oxopiperidin-1-yl)carbonyl]phenyl}-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(morpholin-4-ylcarbonyl)phenyl]-1-benzofuran-2-sulfonamide; N-{5-chloro-2-[(2-methylpyridin-3-yl)oxy]phenyl}-1-benzofuran-2-sulfonamide; methyl 2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}benzoate; 2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}benzoic acid; N-[5-chloro-2-(phenylsulfanyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(phenylsulfonyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(phenylsulfinyl)phenyl]-1-benzofuran-2-sulfonamide; 2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chloro-N-phenylbenzamide; N-(5-chloro-2-cyanophenyl)-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(phenylacetyl)phenyl]-1-benzofuran-2-sulfonamide; N-{5-chloro-2-[(1Z)—N-methoxy-2-phenylethanimidoyl]phenyl}-1-benzofuran-2-sulfonamide; N-{5-chloro-2-[(1Z)—N-hydroxy-2-phenylethanimidoyl]phenyl}-1-benzofuran-2-sulfonamide; N-[2-(benzyloxy)-5-chlorophenyl]-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(phenylethynyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-chloro-2-(2-phenylethyl)phenyl]-1-benzofuran-2-sulfonamide; N-{5-chloro-2-[(Z)-2-phenylethenyl]phenyl}-1-benzofuran-2-sulfonamide; N-[5-methyl-2-(phenylsulfanyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-methyl-2-(phenylsulfinyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-methyl-2-(phenylsulfonyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-fluoro-2-(phenylsulfanyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-fluoro-2-(phenylsulfinyl)phenyl]-1-benzofuran-2-sulfonamide; N-[5-fluoro-2-(phenylsulfonyl)phenyl]-1-benzofuran-2-sulfonamide; methyl 2-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoate; 2-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoic acid; 2-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenyl}sulfanyl)benzoic acid; 3-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenyl}sulfanyl)benzoic acid; 4-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenyl}sulfanyl)benzoic acid; methyl 3-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoate; 3-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoic acid; methyl 2-(2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}ethyl)benzoate; 2-(2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}ethyl)benzoic acid.
[0220] Some compounds of Formula I and some of their intermediates have at least one stereogenic center in their structure. This stereogenic center may be present in an R or S configuration, said R and S notation is used in correspondence with the rules described in Pure Appli. Chem. (1976), 45, 11-13.
[0221] The term “pharmaceutically acceptable salts” refers to salts or complexes that retain the desired biological activity of the above identified compounds and exhibit minimal or no undesired toxicological effects. The “pharmaceutically acceptable salts” according to the invention include therapeutically active, non-toxic base or acid salt forms, which the compounds of Formula I are able to form.
[0222] The acid addition salt form of a compound of Formula I that occurs in its free form as a base can be obtained by treating the free base with an appropriate acid such as an inorganic acid, for example, hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, nitric acid and the like; or an organic acid such as for example, acetic, hydroxyacetic, propanoic, lactic, pyruvic, malonic, fumaric acid, maleic acid, oxalic acid, tartaric acid, succinic acid, malic acid, ascorbic acid, benzoic acid, tannic acid, pamoic acid, citric, methylsulfonic, ethanesulfonic, benzenesulfonic, formic acid and the like (Handbook of Pharmaceutical Salts, P. Heinrich Stahal & Camille G. Wermuth (Eds), Verlag Helvetica Chemica Acta-Zürich, 2002, 329-345).
[0223] The base addition salt form of a compound of Formula I that occurs in its acid form can be obtained by treating the acid with an appropriate base such as an inorganic base, for example, sodium hydroxide, magnesium hydroxide, potassium hydroxide, calcium hydroxide, ammonia and the like; or an organic base such as for example, L-Arginine, ethanolamine, betaine, benzathine, morpholine and the like. (Handbook of Pharmaceutical Salts, P. Heinrich Stahal & Camille G. Wermuth (Eds), Verlag Helvetica Chemica Acta-Zürich, 2002, 329-345).
[0224] Compounds of Formula I and their salts can be in the form of a solvate, which is included within the scope of the present invention. Such solvates include for example hydrates, alcoholates and the like.
[0225] With respect to the present invention reference to a compound or compounds, is intended to encompass that compound in each of its possible isomeric forms and mixtures thereof unless the particular isomeric form is referred to specifically.
[0226] Compounds according to the present invention may exist in different polymorphic forms. Although not explicitly indicated in the above formula, such forms are intended to be included within the scope of the present invention.
[0227] The compounds of the invention are indicated for use in treating or preventing conditions in which there is likely to be a component involving the chemokine receptors.
[0228] In another embodiment, there are provided pharmaceutical compositions including at least one compound of the invention in a pharmaceutically acceptable carrier.
[0229] In a further embodiment of the invention, there are provided methods for treating disorders associated with modulation of chemokine receptors. Such methods can be performed, for example, by administering to a subject in need thereof a pharmaceutical composition containing a therapeutically effective amount of at least one compound of the invention.
[0230] These compounds are useful for the treatment of mammals, including humans, with a range of conditions and diseases that are alleviated by chemokine receptor modulation.
[0231] Therapeutic utilities of chemokine receptor modulators are skin inflammatory diseases and conditions, including, but are not limited to: rosacea (dilation of the blood vessels just under the skin), sunburn, chronic sun damage, discreet erythemas, psoriasis, atopic dermatitis, menopause-associated hot flashes, hot flashes resulting from orchiectomyatopic dermatitis, photoaging, seborrheic dermatitis, acne, allergic dermatitis, irritant dermatitis, telangiectasia (dilations of previously existing small blood vessels) of the face, rhinophyma (hypertrophy of the nose with follicular dilation), red bulbous nose, acne-like skin eruptions (may ooze or crust), burning or stinging sensation of the face, irritated and bloodshot and watery eyes, cutaneous hyperactivity with dilation of blood vessels of the skin, Lyell's syndrome, Stevens-Johnson syndrome, erythema multiforme minor, erythema multiforme major and other inflammatory skin diseases, actinic keratoses, arsenic keratoses, inflammatory and non-inflammatory acne, ichthyoses and other keratinization and hyperproliferative disorders of the skin, eczema, wound healing.
[0232] Therapeutic utilities of chemokine receptor modulators are ocular inflammatory diseases including, but not limited to, uveitis, dry eye, keratitis, allergic eye disease and conditions affecting the posterior part of the eye, such as maculopathies and retinal degeneration including non-exudative age related macular degeneration, exudative age related macular degeneration, choroidal neovascularization, diabetic retinopathy, acute macular neuroretinopathy, central serous chorioretinopathy, cystoid macular edema, and diabetic macular edema; uveitis, retinitis, and choroiditis such as acute multifocal placoid pigment epitheliopathy, Behcet's disease, birdshot retinochoroidopathy, infectious (syphilis, lyme, tuberculosis, toxoplasmosis), intermediate uveitis (pars planitis), multifocal choroiditis, multiple evanescent white dot syndrome (mewds), ocular sarcoidosis, posterior scleritis, serpiginous choroiditis, subretinal fibrosis and uveitis syndrome, Vogt-Koyanagi- and Harada syndrome; vasuclar diseases/exudative diseases such as retinal arterial occlusive disease, central retinal vein occlusion, disseminated intravascular coagulopathy, branch retinal vein occlusion, hypertensive fundus changes, ocular ischemic syndrome, retinal arterial microaneurysms, Coat's disease, parafoveal telangiectasis, hemi-retinal vein occlusion, papillophlebitis, central retinal artery occlusion, branch retinal artery occlusion, carotid artery disease (CAD), frosted branch angiitis, sickle cell retinopathy and other hemoglobinopathies, angioid streaks, familial exudative vitreoretinopathy, and Eales disease; traumatic/surgical conditions such as sympathetic ophthalmia, uveitic retinal disease, retinal detachment, trauma, conditions caused by laser, conditions caused by photodynamic therapy, photocoagulation, hypoperfusion during surgery, radiation retinopathy, and bone marrow transplant retinopathy; proliferative disorders such as proliferative vitreal retinopathy and epiretinal membranes, and proliferative diabetic retinopathy; infectious disorders such as ocular histoplasmosis, ocular toxocariasis, presumed ocular histoplasmosis syndrome (PONS), endophthalmitis, toxoplasmosis, retinal diseases associated with HIV infection, choroidal disease associate with HIV infection, uveitic disease associate with HIV infection, viral retinitis, acute retinal necrosis, progressive outer retinal necrosis, fungal retinal diseases, ocular syphilis, ocular tuberculosis, diffuse unilateral subacute neuroretinitis, and myiasis; genetic disorders such as retinitis pigmentosa, systemic disorders with accosiated retinal dystrophies, congenital stationary night blindness, cone dystrophies, Stargardt's disease and fundus flavimaculatus, Best's disease, pattern dystrophy of the retinal pigmented epithelium, X-linked retinoschisis, Sorsby's fundus dystrophy, benign concentric maculopathy, Bietti's crystalline dystrophy, and pseudoxanthoma elasticum; retinal tears/holes such as retinal detachment, macular hole, and giant retinal tear; tumors such as retinal disease associated with tumors, congenital hypertrophy of the retinal pigmented epithelium, posterior uveal melanoma, choroidal hemangioma, choroidal osteoma, choroidal metastasis, combined hamartoma of the retina and retinal pigmented epithelium, retinoblastoma, vasoproliferative tumors of the ocular fundus, retinal astrocytoma, and intraocular lymphoid tumors; and miscellaneous other diseases affecting the posterior part of the eye such as punctate inner choroidopathy, acute posterior multifocal placoid pigment epitheliopathy, myopic retinal degeneration, and acute retinal pigement epitheliitis.
[0233] In still another embodiment of the invention, there are provided methods for treating disorders associated with modulation of chemokine receptors. Such methods can be performed, for example, by administering to a subject in need thereof a therapeutically effective amount of at least one compound of the invention, or any combination thereof, or pharmaceutically acceptable salts, hydrates, solvates, crystal forms and individual isomers, enantiomers, and diastereomers thereof.
[0234] The present invention concerns the use of a compound of Formula I or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of ocular inflammatory diseases including, but not limited to, uveitis, dry eye, Keratitis, allergic eye disease and conditions affecting the posterior part of the eye, such as maculopathies and retinal degeneration including non-exudative age related macular degeneration, exudative age related macular degeneration, choroidal neovascularization, diabetic retinopathy, acute macular neuroretinopathy, central serous chorioretinopathy, cystoid macular edema, and diabetic macular edema; uveitis, retinitis, and choroiditis such as acute multifocal placoid pigment epitheliopathy, Behcet's disease, birdshot retinochoroidopathy, infectious (syphilis, lyme, tuberculosis, toxoplasmosis), intermediate uveitis (pars planitis), multifocal choroiditis, multiple evanescent white dot syndrome (mewds), ocular sarcoidosis, posterior scleritis, serpiginous choroiditis, subretinal fibrosis and uveitis syndrome, Vogt-Koyanagi- and Harada syndrome; vasuclar diseases/exudative diseases such as retinal arterial occlusive disease, central retinal vein occlusion, disseminated intravascular coagulopathy, branch retinal vein occlusion, hypertensive fundus changes, ocular ischemic syndrome, retinal arterial microaneurysms, Coat's disease, parafoveal telangiectasis, hemi-retinal vein occlusion, papillophlebitis, central retinal artery occlusion, branch retinal artery occlusion, carotid artery disease (CAD), frosted branch angiitis, sickle cell retinopathy and other hemoglobinopathies, angioid streaks, familial exudative vitreoretinopathy, and Eales disease; traumatic/surgical conditions such as sympathetic ophthalmia, uveitic retinal disease, retinal detachment, trauma, conditions caused by laser, conditions caused by photodynamic therapy, photocoagulation, hypoperfusion during surgery, radiation retinopathy, and bone marrow transplant retinopathy; proliferative disorders such as proliferative vitreal retinopathy and epiretinal membranes, and proliferative diabetic retinopathy; infectious disorders such as ocular histoplasmosis, ocular toxocariasis, presumed ocular histoplasmosis syndrome (PONS), endophthalmitis, toxoplasmosis, retinal diseases associated with HIV infection, choroidal disease associate with HIV infection, uveitic disease associate with HIV infection, viral retinitis, acute retinal necrosis, progressive outer retinal necrosis, fungal retinal diseases, ocular syphilis, ocular tuberculosis, diffuse unilateral subacute neuroretinitis, and myiasis; genetic disorders such as retinitis pigmentosa, systemic disorders with accosiated retinal dystrophies, congenital stationary night blindness, cone dystrophies, Stargardt's disease and fundus flavimaculatus, Best's disease, pattern dystrophy of the retinal pigmented epithelium, X-linked retinoschisis, Sorsby's fundus dystrophy, benign concentric maculopathy, Bietti's crystalline dystrophy, and pseudoxanthoma elasticum; retinal tears/holes such as retinal detachment, macular hole, and giant retinal tear; tumors such as retinal disease associated with tumors, congenital hypertrophy of the retinal pigmented epithelium, posterior uveal melanoma, choroidal hemangioma, choroidal osteoma, choroidal metastasis, combined hamartoma of the retina and retinal pigmented epithelium, retinoblastoma, vasoproliferative tumors of the ocular fundus, retinal astrocytoma, and intraocular lymphoid tumors; and miscellaneous other diseases affecting the posterior part of the eye such as punctate inner choroidopathy, acute posterior multifocal placoid pigment epitheliopathy, myopic retinal degeneration, and acute retinal pigement epitheliitis.
[0235] The actual amount of the compound to be administered in any given case will be determined by a physician taking into account the relevant circumstances, such as the severity of the condition, the age and weight of the patient, the patient's general physical condition, the cause of the condition, and the route of administration.
[0236] The patient will be administered the compound orally in any acceptable form, such as a tablet, liquid, capsule, powder and the like, or other routes may be desirable or necessary, particularly if the patient suffers from nausea. Such other routes may include, without exception, transdermal, parenteral, subcutaneous, intranasal, via an implant stent, intrathecal, intravitreal, topical to the eye, back to the eye, intramuscular, intravenous, and intrarectal modes of delivery. Additionally, the formulations may be designed to delay release of the active compound over a given period of time, or to carefully control the amount of drug released at a given time during the course of therapy.
[0237] In another embodiment of the invention, there are provided pharmaceutical compositions including at least one compound of the invention in a pharmaceutically acceptable carrier thereof. The phrase “pharmaceutically acceptable” means the carrier, diluent or excipient must be compatible with the other ingredients of the formulation and not deleterious to the recipient thereof.
[0238] Pharmaceutical compositions of the present invention can be used in the form of a solid, a solution, an emulsion, a dispersion, a patch, a micelle, a liposome, and the like, wherein the resulting composition contains one or more compounds of the present invention, as an active ingredient, in admixture with an organic or inorganic carrier or excipient suitable for enteral or parenteral applications. Invention compounds may be combined, for example, with the usual non-toxic, pharmaceutically acceptable carriers for tablets, pellets, capsules, suppositories, solutions, emulsions, suspensions, and any other form suitable for use. The carriers which can be used include glucose, lactose, gum acacia, gelatin, mannitol, starch paste, magnesium trisilicate, talc, corn starch, keratin, colloidal silica, potato starch, urea, medium chain length triglycerides, dextrans, and other carriers suitable for use in manufacturing preparations, in solid, semisolid, or liquid form. In addition auxiliary, stabilizing, thickening and coloring agents and perfumes may be used. Invention compounds are included in the pharmaceutical composition in an amount sufficient to produce the desired effect upon the process or disease condition.
[0239] Pharmaceutical compositions containing invention compounds may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Compositions intended for oral use may be prepared according to any method known in the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of a sweetening agent such as sucrose, lactose, or saccharin, flavoring agents such as peppermint, oil of wintergreen or cherry, coloring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets containing invention compounds in admixture with non-toxic pharmaceutically acceptable excipients may also be manufactured by known methods. The excipients used may be, for example, (1) inert diluents such as calcium carbonate, lactose, calcium phosphate or sodium phosphate; (2) granulating and disintegrating agents such as corn starch, potato starch or alginic acid; (3) binding agents such as gum tragacanth, corn starch, gelatin or acacia, and (4) lubricating agents such as magnesium stearate, stearic acid or talc. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed.
[0240] In some cases, formulations for oral use may be in the form of hard gelatin capsules wherein the invention compounds are mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin. They may also be in the form of soft gelatin capsules wherein the invention compounds are mixed with water or an oil medium, for example, peanut oil, liquid paraffin or olive oil.
[0241] The pharmaceutical compositions may be in the form of a sterile injectable suspension. This suspension may be formulated according to known methods using suitable dispersing or wetting agents and suspending agents. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil may be employed including synthetic mono- or diglycerides, fatty acids (including oleic acid), naturally occurring vegetable oils like sesame oil, coconut oil, peanut oil, cottonseed oil, etc., or synthetic fatty vehicles like ethyl oleate or the like. Buffers, preservatives, antioxidants, and the like can be incorporated as required.
[0242] Invention compounds and their pharmaceutically-acceptable salts may be administered through different routes, including but not limited to topical eye drops, direct injection, application at the back of the eye or formulations that may further enhance the long duration of actions such as a slow releasing pellet, suspension, gel, or sustained delivery devices such as any suitable drug delivery system (DDS) known in the art. While topical administration is preferred, this compound may also be used in an intraocular implant as described in U.S. Pat. No. 7,931,909.
[0243] Invention compounds may also be administered in the form of suppositories for rectal administration of the drug. These compositions may be prepared by mixing the invention compounds with a suitable non-irritating excipient, such as cocoa butter, synthetic glyceride esters of polyethylene glycols, which are solid at ordinary temperatures, but liquefy and/or dissolve in the rectal cavity to release the drug.
[0244] Since individual subjects may present a wide variation in severity of symptoms and each drug has its unique therapeutic characteristics, the precise mode of administration and dosage employed for each subject is left to the discretion of the practitioner.
[0245] The compounds and pharmaceutical compositions described herein are useful as medicaments in mammals, including humans, for treatment of diseases and/or alleviations of conditions which are responsive to treatment by agonists or functional antagonists of chemokine receptors. Thus, in further embodiments of the invention, there are provided methods for treating a disorder associated with modulation of chemokine receptors. Such methods can be performed, for example, by administering to a subject in need thereof a pharmaceutical composition containing a therapeutically effective amount of at least one invention compound. As used herein, the term “therapeutically effective amount” means the amount of the pharmaceutical composition that will elicit the biological or medical response of a subject in need thereof that is being sought by the researcher, veterinarian, medical doctor or other clinician. In some embodiments, the subject in need thereof is a mammal. In some embodiments, the mammal is human.
[0246] The present invention concerns also processes for preparing the compounds of Formula I. The compounds of formula I according to the invention can be prepared analogously to conventional methods as understood by the person skilled in the art of synthetic organic chemistry. The described benzofuran-2-sulfonamide derivatives were prepared by methods as shown in Scheme 1. Those skilled in the art will be able to routinely modify and/or adapt Scheme 1 to synthesize any compounds of the invention covered by Formula I.
[0000]
DETAILED DESCRIPTION OF THE INVENTION
[0247] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention claimed. As used herein, the use of the singular includes the plural unless specifically stated otherwise.
[0248] It will be readily apparent to those skilled in the art that some of the compounds of the invention may contain one or more asymmetric centers, such that the compounds may exist in enantiomeric as well as in diastereomeric forms. Unless it is specifically noted otherwise, the scope of the present invention includes all enantiomers, diastereomers and racemic mixtures. Some of the compounds of the invention may form salts with pharmaceutically acceptable acids or bases, and such pharmaceutically acceptable salts of the compounds described herein are also within the scope of the invention.
[0249] The present invention includes all pharmaceutically acceptable isotopically enriched compounds. Any compound of the invention may contain one or more isotopic atoms enriched or different than the natural ratio such as deuterium 2 H (or D) in place of protium 1 H (or H) or use of 13 C enriched material in place of 12 C and the like. Similar substitutions can be employed for N, O and S. The use of isotopes may assist in analytical as well as therapeutic aspects of the invention. For example, use of deuterium may increase the in vivo half-life by altering the metabolism (rate) of the compounds of the invention. These compounds can be prepared in accord with the preparations described by use of isotopically enriched reagents.
[0250] As will be evident to those skilled in the art, individual isomeric forms can be obtained by separation of mixtures thereof in conventional manner. For example, in the case of diasteroisomeric isomers, chromatographic separation may be employed.
[0251] Compound names were generated with ACD version 12.0 and some intermediates' and reagents' names used in the examples were generated with software such as Chem Bio Draw Ultra version 12.0 or Auto Nom 2000 from MDL ISIS Draw 2.5 SP1. In general, characterization of the compounds is performed according to the following methods:
[0252] NMR spectra are recorded on Varian 600 or Varian 300, in the indicated solvent at ambient temperature; chemical shifts in [ppm], coupling constants in [Hz].
[0253] All the reagents, solvents, catalysts for which the synthesis is not described are purchased from chemical vendors such as Sigma Aldrich, Fluka, Bio-Blocks, Combi-blocks, TCI, VWR, Lancaster, Oakwood, Trans World Chemical, Alfa, Fisher, Maybridge, Frontier, Matrix, Ukrorgsynth, Toronto, Ryan Scientific, SiliCycle, Anaspec, Syn Chem, Chem-Impex, MIC-scientific, Ltd; however some known intermediates were prepared according to published procedures. Solvents were purchased from commercial sources in appropriate quality and used as received. Air and/or moisture-sensitive reactions were run under an Ar- or N 2 -atmosphere.
[0254] Usually the compounds of the invention were purified by chromatography: CombiFlash Companion and RediSep Rf silica gel 60 (0.04-0.063 mm); Preparative thin layer chromatography (PTLC): Analtech (silica gel 60 F 254 , 500 or 1000 μm).
[0255] The following abbreviations are used in the examples:
CH 2 Cl 2 dichloromethane NaOH sodium hydroxide MeOH methanol CD 3 OD deuterated methanol HCl hydrochloric acid HBTU 2-(1H-Benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate) CuI copper iodide DMF dimethylformamide EtOAc ethyl acetate CDCl 3 deuterated chloroform CHCl 3 chloroform DMSO-d 6 deuterated dimethyl sulfoxide THF tetrahydrofuran K 2 CO 3 potassium carbonate N 2 nitrogen Et 3 N triethylamine Na 2 SO 4 sodium sulfate Pd(PPh 3 ) 2 Cl 2 Bis(triphenylphosphine)palladium(II) dichloride iPr 2 NEt N,N′-diisopropylethylamine EDC N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride MPLC medium pressure liquid chromatography NH 4 Cl Ammonium chloride DMAP N,N-Dimethylpyridin-4-amine mCPBA 3-Chloroperoxybenzoic add SeO 2 Selenium dioxide KOH potassium hydroxide Et 2 O diethylether LiBr lithium bromide K 2 CO 3 potassium carbonate TMSCH N 2 trimethylsilyldiazomethane
Example 1
Compound 1
N-(5-Chloro-2-methoxyphenyl)benzofuran-2-sulfonamide
[0286]
[0287] To a solution of 5-chloro-2-methoxyaniline (100 mg, 0.63 mmol) in pyridine (1 ml) at room temperature was added benzofuran-2-sulfonyl chloride (137 mg, 0.63 mmol) and the reaction was stirred during 64 hours and then was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (25% EtOAc in hexanes) to yield Compound 1 as a light yellow solid (194 mg, 91%).
[0288] 1 H NMR (CHLOROFORM-d) δ: 7.65 (d, J=7.9 Hz, 1H), 7.59 (d, J=2.3 Hz, 1H), 7.53 (d, J=8.2 Hz, 1H), 7.46 (t, J=7.8 Hz, 1H), 7.39 (d, J=0.9 Hz, 1H), 7.30-7.34 (m, 2H), 7.02 (dd, J=8.8, 2.3 Hz, 1H), 6.68 (d, J=8.5 Hz, 1H), 3.68 (s, 3H).
Example 2
Compound 2
N-(5-Chloro-2-methylphenyl)-1-benzofuran-2-sulfonamide
[0289]
[0290] To a solution of 5-chloro-2-methylaniline (50 μl, 0.62 mmol) in pyridine (1 ml) at room temperature was added benzofuran-2-sulfonyl chloride (135 mg, 0.62 mmol) and the reaction was stirred during 64 hours and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (20% EtOAc in hexanes) to yield Compound 2 as a white solid (177 mg, 89%).
[0291] 1 H NMR (CHLOROFORM-d) δ: 7.64 (d, J=7.9 Hz, 1H), 7.53 (d, J=8.5 Hz, 1H), 7.47 (ddd, J=8.4, 7.3, 1.3 Hz, 1H), 7.40 (d, J=2.1 Hz, 1H), 7.31-7.36 (m, 2H), 7.00-7.07 (m, 2H), 6.63-6.77 (m, 1H), 2.14 (s, 3H).
Example 3
Compound 3
N-[5-Chloro-2-(trifluoromethoxy)phenyl]-1-benzofuran-2-sulfonamide
[0292]
[0293] To a solution of 5-chloro-2-(trifluoromethoxy)aniline (106 mg, 0.50 mmol) in pyridine (1 ml) at room temperature was added benzofuran-2-sulfonyl chloride (109 mg, 0.50 mmol) and the reaction was stirred during 72 hours and was concentrated in vacuo. The residue was treated with 4M NaOH (1 ml) in MeOH (3 ml) at room temperature for 30 minutes, acidified with 6M HCl, diluted with brine, and was extracted with EtOAc. The organic layer was dried over Na 2 SO 4 , and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (10% EtOAc in hexanes) to yield Compound 3 as an off-white solid (76 mg, 39%).
[0294] 1 H NMR (CHLOROFORM-d) δ: 7.75 (d, J=2.1 Hz, 1H), 7.65 (d, J=7.9 Hz, 1H), 7.50-7.53 (m, 1H), 7.44-7.49 (m, 2H), 7.32 (t, J=7.2 Hz, 1H), 7.07-7.12 (m, 2H).
Example 4
Compound 4
Methyl 2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorobenzoate
[0295]
[0296] To a solution of methyl 2-amino-4-chlorobenzoate (93 mg, 0.50 mmol) in pyridine (1 ml) at room temperature was added benzofuran-2-sulfonyl chloride (109 mg, 0.50 mmol) and the reaction was stirred for 72 hours and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (10% EtOAc in hexanes) to yield Compound 4 as a white solid (101 mg, 55%).
[0297] 1 H NMR (CHLOROFORM-d) δ: 11.13 (s, 1H), 7.90 (d, J=8.5 Hz, 1H), 7.84 (s, 1H), 7.69 (d, J=8.5 Hz, 1H), 7.51-7.55 (m, 2H), 7.46 (t, J=7.9 Hz, 1H), 7.31-7.36 (m, 1H), 7.05 (dd, J=8.5, 2.1 Hz, 1H), 3.92 (s, 3H).
Example 5
Compound 5
N-(5-Chloro-2-ethoxyphenyl)-1-benzofuran-2-sulfonamide
[0298]
[0299] To a solution of 5-chloro-2-ethoxyaniline (148 mg, 0.86 mmol) in pyridine (2 ml) benzofuran-2-sulfonyl chloride (189 mg, 0.86 mmol) was added at room temperature and the reaction was stirred for 16 hours and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (10-20% EtOAc in hexanes) to yield Compound 5 as an off-white solid (229 mg, 75%).
[0300] 1 H NMR (CHLOROFORM-d) δ: 7.63 (d, J=7.9 Hz, 1H), 7.58 (d, J=2.3 Hz, 1H), 7.48-7.51 (m, 1H), 7.41-7.46 (m, 1H), 7.36 (s, 1H), 7.28-7.33 (m, 2H), 6.98 (dd, J=8.7, 2.5 Hz, 1H), 6.64 (d, J=8.8 Hz, 1H), 3.86 (q, J=6.8 Hz, 2H), 1.26-1.31 (m, 3H).
Example 6
Intermediate 1
5-Chloro-2-((trimethylsilyl)ethynyl)aniline
[0301]
[0302] To a solution of 5-chloro-2-iodoaniline (1.50 g, 5.92 mmol) and ethynyltrimethylsilane (1.25 ml, 8.88 mmol) in Et 3 N (20 ml) was added CuI (5.6 mg, 0.030 mmol) and Pd(PPh 3 ) 2 Cl 2 (21 mg, 0.030 mmol) and the mixture was stirred at room temperature for 5 hours. Celite was added and the suspension was filtered, rinsed with EtOAc. The filtrate was concentrated in vacuo to yield Intermediate 1 as a yellow oil (1.32 g, 100%).
[0303] 1 H NMR (CHLOROFORM-d) δ: 7.20 (d, J=8.2 Hz, 1H), 6.69 (d, J=1.8 Hz, 1H), 6.63 (dd, J=8.2, 2.1 Hz, 1H), 4.30 (br. s., 2H), 0.27 (s, 9H).
Example 7
Intermediate 2
N-(5-Chloro-2-((trimethylsilyl)ethynyl)phenyl)benzofuran-2-sulfonamide
[0304]
[0305] To a solution of Intermediate 1 (1.32 g, 5.89 mmol) in pyridine (12 ml) was added benzofuran-2-sulfonyl chloride (1.53 g, 7.07 mmol) and the reaction was stirred at room temperature for 16 hours and was concentrated in vacuo. The residue was taken in EtOAc, washed with 1M HCl, brine, dried over Na 2 SO 4 , and concentrated in vacuo to yield crude Intermediate 2 as a reddish brown solid (3.5 g). The crude product was used in the next step without further purification.
Example 8
Compound 6
N-(5-Chloro-2-ethynylphenyl)-1-benzofuran-2-sulfonamide
[0306]
[0307] To a solution of crude Intermediate 2 (3.43 g, 8.49 mmol) in MeOH (50 ml) was added K 2 CO 3 (2.45 g, 17.8 mmol) and the mixture was stirred at room temperature for 16 hours. The solvent was removed, and the residue was acidified, extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-25% EtOAc in hexanes) to yield Compound 6 as a light brown solid (1.47 g, 75%).
[0308] 1 H NMR (CHLOROFORM-d) δ: 7.69 (d, J=2.1 Hz, 1H), 7.68 (d, J=7.9 Hz, 1H), 7.54 (dd, J=8.5, 0.9 Hz, 1H), 7.49 (dd, J=7.0, 1.2 Hz, 2H), 7.47 (d, J=0.9 Hz, 1H), 7.32-7.37 (m, 1H), 7.31 (d, J=8.2 Hz, 1H), 7.05 (dd, J=8.2, 2.1 Hz, 1H), 3.47 (s, 1H).
Example 9
Intermediate 3
1-(2-Amino-4-chlorobenzoyl)piperidin-4-one
[0309]
[0310] To 2-amino-4-chlorobenzoic acid (0.86 g, 5.0 mmol) and piperidin-4-one hydrochloride (0.77 g, 5.0 mmol) in DMF (10 ml) was added HBTU (1.90 g, 5.0 mmol) and iPr 2 NEt (2.6 ml, 15 mmol). The mixture was stirred at room temperature for 16 hours, diluted with 1M NaOH, extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (50-75% EtOAc in hexanes) to yield Intermediate 3
[0000] as a light yellow solid (1.35 g, 100%).
[0311] 1 H NMR (acetone) δ: 7.18 (d, J=8.2 Hz, 1H), 6.86 (d, J=1.8 Hz, 1H), 6.64 (dd, J=8.2, 2.1 Hz, 1H), 5.30 (br. s., 2H), 3.85 (t, J=6.2 Hz, 4H), 2.48 (t, J=6.3 Hz, 4H).
Example 10
Compound 7
N-{5-Chloro-2-[(4-oxopiperidin-1-yl)carbonyl]phenyl}-1-benzofuran-2-sulfonamide
[0312]
[0313] To Intermediate 3 (90 mg, 0.36 mmol) in pyridine (1.5 ml) was added benzofuran-2-sulfonyl chloride (77 mg, 0.36 mmol) and the reaction was stirred at room temperature for 6 hours and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (50-70% EtOAc in hexanes) followed by PTLC (50% EtOAc in hexanes) to yield Compound 7 (40 mg, 26%).
[0314] 1H NMR (CHLOROFORM-d) δ: 8.97 (s, 1H), 7.82 (s, 1H), 7.67 (d, J=7.9 Hz, 1H), 7.45-7.54 (m, 2H), 7.43 (s, 1H), 7.35 (t, J=7.5 Hz, 1H), 7.17 (s, 2H), 3.65 (br. s., 4H), 2.31 (br. s., 4H).
Example 11
Intermediate 4
(2-Amino-4-chlorophenyl)(morpholino)methanone
[0315]
[0316] To 2-amino-4-chlorobenzoic acid (1.72 g, 10.0 mmol) and morpholine (1.3 ml, 15.0 mmol) in DMF (10 ml) was added EDC (2.30 g, 12.0 mmol). The mixture was stirred at room temperature for 16 hours, diluted with H 2 O, extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (50% EtOAc in hexanes) to yield Intermediate 4 as an off-white solid (2.14 g, 89%).
[0317] 1H NMR (CHLOROFORM-d) δ: 7.00 (d, J=8.2 Hz, 1H), 6.66-6.75 (m, 2H), 4.49 (br. s., 2H), 3.67-3.75 (m, 4H), 3.63 (d, J=5.0 Hz, 4H).
Example 12
Compound 8
N-[5-Chloro-2-(morpholin-4-ylcarbonyl)phenyl]-1-benzofuran-2-sulfonamide
[0318]
[0319] To Intermediate 4 (120 mg, 0.50 mmol) in pyridine (2 ml) was added benzofuran-2-sulfonyl chloride (108 mg, 0.50 mmol) and the reaction was stirred at room temperature for 6 hours and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (50-70% EtOAc in hexanes) followed by PTLC (60% EtOAc in hexanes) to yield Compound 8 as an off-white solid (133 mg, 63%).
Example 13
Intermediate 5
3-(4-Chloro-2-nitrophenoxy)-2-methylpyridine
[0320]
[0321] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (720 mg, 4.10 mmol) in DMF (10 ml) was added 2-methylpyridin-3-ol (448 mg, 4.10 mmol) and K 2 CO 3 (2.8 g, 20.5 mmol) and the reaction was stirred at 60° C. for 3 hours, diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 5 as a yellow solid (1.03 g, 94%).
[0322] 1 H NMR (600 MHz, acetone) δ 8.35 (d, J=4.70 Hz, 1H), 8.11 (d, J=2.64 Hz, 1H), 7.71 (dd, J=2.49, 8.95 Hz, 1H), 7.40 (d, J=8.22 Hz, 1H), 7.27 (dd, J=4.70, 8.22 Hz, 1H), 7.11 (d, J=9.10 Hz, 1H), 2.45 (s, 3H).
Example 14
Intermediate 6
5-Chloro-2-((2-methylpyridin-3-yl)oxy)aniline
[0323]
[0324] To a solution of Intermediate 5 (1.03 g, 3.9 mmol) in MeOH (15 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (6.3 g, 98 mmol). The suspension was stirred at room temperature for 2 hour and was filtered, the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 6 (740 mg, 81%) was used in the next reaction without further purification.
[0325] 1 H NMR (600 MHz, CD 3 OD) δ 8.11 (d, J=4.99 Hz, 1H), 7.19 (dd, J=4.99, 8.22 Hz, 1H), 7.09 (dd, J=1.17, 8.22 Hz, 1H), 6.88 (d, J=2.35 Hz, 1H), 6.67 (d, J=8.51 Hz, 1H), 6.59 (dd, J=2.64, 8.51 Hz, 1H), 2.55 (s, 3H).
Example 15
Compound 9
N-{5-Chloro-2-[(2-methylpyridin-3-yl)oxy]phenyl}-1-benzofuran-2-sulfonamide
[0326]
[0327] To Intermediate 6 (488 mg, 2.1 mmol) in pyridine (4 ml) was added benzofuran-2-sulfonyl chloride (450 mg, 2.1 mmol) and the reaction was stirred at room temperature for 16 hours. Solvent was removed in vacuo and the crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) followed by re-crystallization from 20% EtOAc/Hexane to yield Compound 9 (553 mg, 64%) as a yellow solid.
[0328] 1 H NMR (600 MHz, CD 3 OD) δ 8.03 (dd, J=1.17, 4.70 Hz, 1H), 7.68 (d, J=7.92 Hz, 1H), 7.63 (d, J=2.64 Hz, 1H), 7.39-7.48 (m, 2H), 7.31-7.37 (m, 2H), 7.15 (dd, J=2.64, 8.80 Hz, 1H), 6.87 (dd, J=4.69, 8.22 Hz, 1H), 6.69 (dd, J=1.17, 8.22 Hz, 1H), 6.60 (d, J=8.51 Hz, 1H), 2.20 (s, 3H).
Example 16
Intermediate 7
Methyl 2-(4-chloro-2-nitrophenoxy)benzoate
[0329]
[0330] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (588 mg, 3.35 mmol) in DMF (10 ml) was added methyl 2-hydroxybenzoate (509 mg, 3.35 mmol) and K 2 CO 3 (2.31 g, 16.75 mmol) and the reaction was stirred at 60° C. for 3 hours, diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 7
[0000] as yellow oil (1.0 g, 99%).
[0331] 1 H NMR (600 MHz, CD 3 OD) δ 8.03 (d, J=2.35 Hz, 1H), 8.00 (dd, J=1.61, 7.78 Hz, 1H), 7.62-7.70 (m, 1H), 7.54 (dd, J=2.64, 9.10 Hz, 1H), 7.39 (td, J=1.17, 7.63 Hz, 1H), 7.20 (dd, J=0.88, 8.22 Hz, 1H), 6.84 (d, J=9.10 Hz, 1H), 3.74 (s, 3H).
Example 17
Intermediate 8
Methyl 2-((3-amino-5-chloropyridin-2-yl)oxy)benzoate
[0332]
[0333] To a solution of Intermediate 7 (1.0 g, 3.26 mmol) in MeOH (30 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (5.3 g, 81 mmol). The suspension was stirred at room temperature for 1 hour and was filtered, the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 8 (770 mg, 85%) was used in the next reaction without further purification.
[0334] 1 H NMR (600 MHz, CD 3 OD) δ 7.82 (dd, J=1.76, 7.92 Hz, 1H), 7.43-7.50 (m, 1H), 7.12-7.18 (m, 1H), 6.90 (d, J=7.92 Hz, 1H), 6.85 (d, J=2.35 Hz, 1H), 6.70 (d, J=8.51 Hz, 1H), 6.58 (dd, J=2.20, 8.66 Hz, 1H), 3.85 (s, 3H).
Example 18
Compound 10
Methyl 2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}benzoate
[0335]
[0336] To Intermediate 8 (770 mg, 2.53 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (546 mg, 2.53 mmol) and the reaction was stirred at room temperature for 16 hours. Solvent was removed in vacuo and the crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 10 (920 mg, 72%) as a yellow solid.
[0337] 1 H NMR (600 MHz, CD 3 OD) δ 7.79 (dd, J=2.35, 7.04 Hz, 1H), 7.65-7.69 (m, 2H), 7.42-7.46 (m, 1H), 7.35-7.38 (m, 2H), 7.30-7.35 (m, 1H), 7.09 (dd, J=2.64, 8.80 Hz, 1H), 7.02-7.08 (m, 2H), 6.63 (d, J=8.51 Hz, 1H), 6.28 (dd, J=1.61, 7.78 Hz, 1H), 3.74 (s, 3H).
Example 19
Compound 11
2-{2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}benzoic acid
[0338]
[0339] To Compound 10 (354 mg, 0.78 mmol) in MeOH (30 ml) was added NaOH (5M, 2 ml) and stirred at room temperature for 3 hours. The mixture was acidified with 10% HCl, extracted with EtOAc (×2). The combined organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was recrystallized from minimal MeOH and CH 2 Cl 2 to yield Compound 11 (278 mg, 81%).
[0340] 1 H NMR (600 MHz, CD 3 OD) δ 7.81 (d, J=7.34 Hz, 1H), 7.69 (d, J=2.05 Hz, 1H), 7.65 (d, J=7.92 Hz, 1H), 7.40-7.45 (m, 1H), 7.29-7.37 (m, 3H), 7.11 (dd, J=1.76, 8.51 Hz, 1H), 6.99 (t, J=7.63 Hz, 1H), 6.89-6.95 (m, 1H), 6.72 (d, J=8.80 Hz, 1H), 6.18 (d, J=8.22 Hz, 1H).
Example 20
Intermediate 9
(4-Chloro-2-nitrophenyl)(phenyl)sulfane
[0341]
[0342] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (926 mg, 5.0 mmol) in MeOH (5 ml) was added benzenethiol (0.51 ml, 5.0 mmol) and 4M NaOH (1.25 ml, 5.0 mmol) and the reaction was stirred at room temperature for 4 hours, diluted with 1M NaOH, extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-5% EtOAc in hexanes) to yield Intermediate 9 as a yellow solid (1.31 g, 98%).
[0343] 1H NMR (CHLOROFORM-d) δ: 8.23 (d, J=2.3 Hz, 1H), 7.56-7.61 (m, 2H), 7.48-7.53 (m, 3H), 7.30 (dd, J=8.8, 2.3 Hz, 1H), 6.80 (d, J=8.8 Hz, 1H).
Example 21
Intermediate 10
5-Chloro-2-(phenylthio)aniline
[0344]
[0345] To a solution of Intermediate 9 (0.64 g, 2.4 mmol) in MeOH (20 ml) and THF (20 ml) was added saturated aqueous NH 4 Cl (20 ml) and zinc dust (3.95 g, 61 mmol). The suspension was stirred at room temperature for 3 hours and was filtered; the filtrate was extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (5-10% EtOAc in hexanes) to yield Intermediate 10 as an off-white solid (555 mg, 98%).
[0346] 1H NMR (CHLOROFORM-d) δ: 7.38 (d, J=8.2 Hz, 1H), 7.24 (t, J=7.6 Hz, 2H), 7.14 (t, J=7.3 Hz, 1H), 7.09 (d, J=8.2 Hz, 2H), 6.80 (d, J=2.3 Hz, 1H), 6.74 (dd, J=8.2, 2.1 Hz, 1H), 4.42 (br. s., 2H).
Example 22
Compound 12
N-[5-Chloro-2-(phenylsulfanyl)phenyl]-1-benzofuran-2-sulfonamide
[0347]
[0348] To Intermediate 10 (394 mg, 1.67 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (362 mg, 1.67 mmol) and the reaction was stirred at room temperature for 72 hours, when additional benzofuran-2-sulfonyl chloride (362 mg, 1.67 mmol) and catalytic amount of DMAP was added. The reaction was heated at 100° C. for 6 hours and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (0-5% EtOAc in hexanes) to yield Compound 12 as an off-white solid (425 mg, 61%).
[0349] 1H NMR (CHLOROFORM-d) δ: 8.03 (s, 1H), 7.85 (d, J=2.1 Hz, 1H), 7.66 (dt, J=8.1, 0.9 Hz, 1H), 7.39-7.48 (m, 4H), 7.31-7.37 (m, 1H), 7.04-7.11 (m, 4H), 6.89-6.93 (m, 2H).
Example 23
Compound 13
N-[5-Chloro-2-(phenylsulfonyl)phenyl]-1-benzofuran-2-sulfonamide
[0350]
[0351] To a solution of Compound 12 (333 mg, 0.80 mmol) in CH 2 Cl 2 (5 ml) was added mCPBA (208 mg, ˜1.20 mmol) and the reaction was stirred at room temperature for 2 hours and was concentrated. The residue was purified by flash column chromatography on silica gel (0-50% EtOAc in hexanes) to yield Compound 13 as a white solid (204 mg, 57%).
[0352] 1H NMR (CHLOROFORM-d) δ: 9.70 (s, 1H), 7.79-7.94 (m, 4H), 7.69 (d, J=7.6 Hz, 1H), 7.34-7.57 (m, 7H), 7.17 (d, J=7.9 Hz, 1H).
Example 24
Compound 14
N-[5-Chloro-2-(phenylsulfinyl)phenyl]-1-benzofuran-2-sulfonamide
[0353]
[0354] To a solution of Compound 12 (333 mg, 0.80 mmol) in CH 2 Cl 2 (5 ml) was added mCPBA (208 mg, ˜1.20 mmol) and the reaction was stirred at room temperature for 2 hours and was concentrated. The residue was purified by flash column chromatography on silica gel (0-50% EtOAc in hexanes) to yield Compound 14 as a white solid (129 mg, 37%).
[0355] 1H NMR (CHLOROFORM-d) δ: 10.66 (s, 1H), 7.78 (d, J=2.1 Hz, 1H), 7.63 (dt, J=7.9, 1.0 Hz, 1H), 7.30-7.52 (m, 10H), 7.12 (dd, J=8.2, 2.1 Hz, 1H).
Example 25
Intermediate 11
2-Amino-4-chloro-N-phenylbenzamide
[0356]
[0357] A mixture of 4-chloro-isatoic anhydride (594 mg, 3.0 mmol), aniline (275 μl, 3.0 mmol), and NaOH (12 mg, 0.3 mmol) in dioxane (5 ml) was refluxed at 110° C. for 2 hours. The mixture was cooled to room temperature and was filtered. The filtrate was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (25% EtOAc in hexanes) to yield Intermediate 11 (200 mg, 27%).
[0358] 1H NMR (CHLOROFORM-d) δ: 7.70 (br. s., 1H), 7.55 (dd, J=8.6, 1.0 Hz, 2H), 7.33-7.43 (m, 3H), 7.13-7.21 (m, 1H), 6.64-6.74 (m, 2H), 5.62 (br. s., 2H).
Example 26
Compound 15
2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chloro-N-phenylbenzamide
[0359]
[0360] To Intermediate 11 (200 mg, 0.81 mmol) in pyridine (2 ml) was added benzofuran-2-sulfonyl chloride (176 mg, 0.81 mmol) and a catalytic amount of DMAP. The reaction was stirred at room temperature for 6 hours, when additional benzofuran-2-sulfonyl chloride (88 mg, 0.41 mmol) was added. The reaction was continued for a total of 120 hours and was concentrated in vacuo. The crude reaction mixture was acidified with 6M HCl, extracted with EtOAc (×3). The combined organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (25% EtOAc in hexanes) to yield Compound 15 as an off-white solid (135 mg, 39%).
[0361] 1H NMR (CHLOROFORM-d) δ: 11.06 (s, 1H), 7.83 (d, J=2.1 Hz, 1H), 7.76 (s, 1H), 7.61 (dt, J=7.7, 1.1 Hz, 1H), 7.43-7.51 (m, 3H), 7.15-7.43 (m, 7H), 7.11 (dd, J=8.5, 2.1 Hz, 1H).
Example 27
Compound 16
N-(5-Chloro-2-cyanophenyl)-1-benzofuran-2-sulfonamide
[0362]
[0363] To 2-amino-4-chlorobenzonitrile (552 mg, 3.62 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (781 mg, 3.62 mmol) and the reaction was stirred at 100° C. for 16 hours, then additional benzofuran-2-sulfonyl chloride (842 mg, 3.90 mmol) was added. The reaction was continued for 24 hours and was concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-100% EtOAc in hexanes) to yield Compound 16 (550 mg, 36%).
[0364] 1 H NMR (600 MHz, CD 3 OD) δ 7.72 (dt, J=1.03, 7.92 Hz, 1H), 7.64 (d, J=8.51 Hz, 1H), 7.57-7.60 (m, 1H), 7.53 (d, J=2.05 Hz, 1H), 7.49-7.52 (m, 1H), 7.41-7.42 (m, 1H), 7.34-7.39 (m, 2H).
Example 28
Compound 17
N-[5-Chloro-2-(phenylacetyl)phenyl]-1-benzofuran-2-sulfonamide
[0365]
[0366] To a solution of Compound 16 (128 mg, 0.39 mmol) in THF (2 ml) was added benzylmagnesium chloride (0.6 ml, 1.16 mmol, 2M in THF) at 0° C. After it was stirred at room temperature for 2 hours, the reaction was quenched with water, extracted with EtOAc (×2), washed with brine, dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 17 (91 mg, 55%).
[0367] 1 H NMR (600 MHz, CDCL 3 ) δ 11.95 (s, 1H), 7.82-7.91 (m, 2H), 7.66 (d, J=7.92 Hz, 1H), 7.47-7.50 (m, 2H), 7.42-7.46 (m, 1H), 7.32 (td, J=1.03, 7.41 Hz, 1H), 7.23-7.30 (m, 3H), 7.14 (d, J=7.04 Hz, 2H), 7.05 (dd, J=2.05, 8.51 Hz, 1H), 4.23 (s, 2H).
Example 29
Compound 18
N-{5-Chloro-2-[(1Z)—N-methoxy-2-phenylethanimidoyl]phenyl}-1-benzofuran-2-sulfonamide
[0368]
[0369] A mixture of Compound 17 (91 mg, 0.214 mmol), O-methylhydroxylamine hydrochloride (177 mg, 2.14 mmol) and TEA (0.8 ml) in THF (2 ml) was heated at 80° C. overnight. The reaction mixture was cooled down to room temperature, diluted with EtOAc, filtered, and the filtrate was concentrated in vacuo. The crude residue was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 18 (56 mg, 58%).
[0370] 1 H NMR (600 MHz, CDCL 3 ) δ 11.70 (s, 1H), 7.75 (d, J=2.05 Hz, 1H), 7.63-7.67 (m, 1H), 7.49-7.53 (m, 1H), 7.43-7.48 (td, J=1.32, 7.85 Hz, 1H), 7.40 (d, J=0.88 Hz, 1H), 7.33 (td, J=1.17, 7.48 Hz, 1H), 7.22 (d, J=8.80 Hz, 1H), 7.09-7.15 (m, 3H), 6.97-7.02 (m, 2H), 6.93 (dd, J=2.20, 8.66 Hz, 1H), 4.18 (s, 3H), 4.01 (s, 2H).
Example 30
Compound 19
N-{5-Chloro-2-[(1Z)—N-hydroxy-2-phenylethanimidoyl]phenyl}-1-benzofuran-2-sulfonamide
[0371]
[0372] The mixture of Compound 17 (121 mg, 0.28 mmol), hydroxylamine hydrochloride (198 mg, 2.80 mmol) and TEA (0.8 ml) in THF (2 ml) was heated at 80° C. overnight. The reaction mixture was cooled down to room temperature, diluted with EtOAc, filtered away salt and filtrate was concentrated in vácuo. The crude residue was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 19 (100 mg, 80%).
[0373] 1 H NMR (600 MHz, CDCl 3 ) δ 11.40 (br. s., 1H), 7.76 (d, J=2.05 Hz, 1H), 7.66 (dt, J=1.03, 7.92 Hz, 1H), 7.50-7.53 (m, 1H), 7.45-7.48 (m, 1H), 7.43 (d, J=0.88 Hz, 1H), 7.30-7.36 (m, 1H), 7.23-7.28 (m, 1H), 7.12-7.17 (m, 3H), 7.02-7.09 (m, 2H), 6.95 (dd, J=2.05, 8.51 Hz, 1H), 4.08 (s, 2H).
Example 31
Intermediate 12
1-(Benzyloxy)-4-chloro-2-nitrobenzene
[0374]
[0375] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (409 mg, 2.33 mmol) in DMF (10 ml) was added phenylmethanol (0.24 ml, 2.33 mmol) and K 2 CO 3 (1.6 g, 11.65 mmol) and the reaction was stirred at 60° C. for 16 hours. The reaction was diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 12 as yellow solid (607 mg, 99%).
[0376] 1 H NMR (600 MHz, CD 3 OD) δ 7.86 (d, J=2.64 Hz, 1H), 7.57 (dd, J=2.79, 8.95 Hz, 1H), 7.43-7.47 (m, 2H), 7.36-7.40 (m, 2H), 7.30-7.35 (m, 2H), 5.27 (s, 2H).
Example 32
Intermediate 13
2-(Benzyloxy)-5-chloroaniline
[0377]
[0378] To a solution Intermediate 12 (605 mg, 2.30 mmol) in MeOH (20 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (3.7 g, 57 mmol). The suspension was stirred at room temperature for 1 hour, was filtered, and the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 13 (475 mg, 89%) was used in the next reaction without further purification.
[0379] 1 H NMR (600 MHz, CD 3 OD) δ 7.42-7.49 (m, 2H), 7.34-7.40 (m, 2H), 7.26-7.33 (m, 1H), 6.80 (d, J=8.80 Hz, 1H), 6.73 (d, J=2.64 Hz, 1H), 6.56 (dd, J=2.49, 8.66 Hz, 1H), 5.07 (s, 2H).
Example 33
Compound 20
N-[2-(Benzyloxy)-5-chlorophenyl]-1-benzofuran-2-sulfonamide
[0380]
[0381] To Intermediate 13 (233 mg, 1.0 mmol) in pyridine (3 ml) was added benzofuran-2-sulfonyl chloride (216 mg, 1.0 mmol) and the reaction was stirred at 100° C. for 16 hours. The solvent was removed in vacuo and the crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield the Compound 20 (304 mg, 74%) as a yellow solid.
[0382] 1 H NMR (600 MHz, acetone) δ 7.76 (dt, J=1.03, 7.92 Hz, 1H), 7.56 (d, J=2.64 Hz, 1H), 7.47-7.53 (m, 2H), 7.45 (d, J=0.59 Hz, 1H), 7.35-7.40 (m, 1H), 7.24-7.31 (m, 3H), 7.20-7.24 (m, 2H), 7.14 (dd, J=2.64, 8.80 Hz, 1H), 7.00 (d, J=9.10 Hz, 1H), 4.95 (s, 2H).
Example 34
Intermediate 14
5-Chloro-2-(phenylethynyl)aniline
[0383]
[0384] To 5-chloro-2-iodoaniline (1.27 g, 5.0 mmol) and ethynylbenzene (0.60 ml, 5.5 mmol) in Et 3 N (10 ml) was added CuI (5.0 mg, 0.025 mmol) and Pd(PPh 3 ) 2 Cl 2 (18 mg, 0.025 mmol) and the mixture was stirred at room temperature for 16 hours, diluted with EtOAc and was filtered through a pad of Celite. The filtrate was concentrated and the residue was purified by flash column chromatography on silica gel (0-10% EtOAc in hexanes) to yield Intermediate 14 as beige solid (1.12 g, 98%).
[0385] 1H NMR (CHLOROFORM-d) δ: 7.46-7.56 (m, 2H), 7.32-7.39 (m, 3H), 7.28 (d, J=8.2 Hz, 1H), 6.66-6.75 (m, 2H), 4.37 (br. s., 2H).
Example 35
Compound 21
N-[5-Chloro-2-(phenylethynyl)phenyl]-1-benzofuran-2-sulfonamide
[0386]
[0387] To Intermediate 14 (506 mg, 2.22 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (482 mg, 2.22 mmol) and a catalytic amount of DMAP. The reaction was stirred at room temperature for 4 hours, when additional benzofuran-2-sulfonyl chloride (121 mg, 0.56 mmol) was added. The reaction was continued for 16 hours and was concentrated in vacuo. The crude reaction mixture was acidified with 1M HCl, extracted with EtOAc (×3). The combined organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (0-5% EtOAc in hexanes) to yield Compound 21 as a white solid (516 mg, 57%).
[0388] 1H NMR (CHLOROFORM-d) δ: 7.71 (d, J=2.1 Hz, 1H), 7.62-7.65 (m, 1H), 7.51-7.54 (m, 2H), 7.49 (s, 1H), 7.38-7.44 (m, 5H), 7.32-7.35 (m, 2H), 7.29-7.32 (m, 1H), 7.10 (dd, J=8.2, 2.1 Hz, 1H).
Example 36
Compound 22
N-[5-Chloro-2-(2-phenylethyl)phenyl]-1-benzofuran-2-sulfonamide
[0389]
[0390] A mixture of Compound 21 (110 mg, 0.27 mmol) and 10% palladium on activated carbon (29 mg, 0.027 mmol) in EtOAc (5 ml) was stirred at room temperature under excess hydrogen gas in a balloon for 4 hours. The mixture was filtered and the filtrate was concentrated to yield Compound 22 as off-white solid (103 mg, 93%).
[0391] 1H NMR (CHLOROFORM-d) δ: 7.60-7.63 (m, 1H), 7.46-7.50 (m, 1H), 7.42-7.46 (m, 1H), 7.30-7.35 (m, 2H), 7.28 (d, J=0.9 Hz, 1H), 7.18-7.27 (m, 3H), 7.10 (dd, J=8.2, 2.3 Hz, 1H), 6.98-7.03 (m, 3H), 6.34 (s, 1H), 2.72-2.79 (m, 4H).
Example 37
Compound 23
N-{5-Chloro-2-[(1Z)-2-phenylethenyl]phenyl}-1-benzofuran-2-sulfonamide
[0392]
[0393] A mixture of Compound 21 (140 mg, 0.34 mmol) and 5% Lindlar's catalyst (Aldrich Lot#BCBG1137V, 144 mg, 0.068 mmol) in EtOAc (5 ml) was stirred at room temperature under excess hydrogen gas in a balloon for 4 hours. The mixture was then place under 50 psi hydrogen gas using a Parr apparatus for 3 h, and was filtered. The filtrate was concentrated and the crude product was purified by flash column chromatography on silica gel (5-10% EtOAc in hexanes) to yield Compound 23 (75 mg, 53%).
[0394] 1H NMR (CHLOROFORM-d) δ: 7.61-7.66 (m, 2H), 7.42-7.48 (m, 2H), 7.30-7.36 (m, 2H), 7.11-7.16 (m, 1H), 7.06-7.11 (m, 2H), 7.01-7.06 (m, 2H), 6.94-6.98 (m, 2H), 6.87 (s, 1H), 6.72 (d, J=12.0 Hz, 1H), 6.25 (d, J=12.0 Hz, 1H).
Example 38
Intermediate 15
(4-Methyl-2-nitrophenyl)(phenyl)sulfane
[0395]
[0396] To a solution of 1-bromo-4-methyl-2-nitrobenzene (1.32 g, 6.11 mmol) in MeOH (10 ml) was added benzenethiol (0.8 ML, 6.11 mmol) and NaOH (1.5 ml, 5M) and the reaction was stirred at room temperature for 16 hours, diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 15
[0000] (1.0 g, 67%).
[0397] 1 H NMR (300 MHz, CDCl 3 ) δ 8.03 (d, J=1.17 Hz, 1H), 7.53-7.59 (m, 2H), 7.43-7.49 (m, 3H), 7.15 (dd, J=2.05, 8.50 Hz, 1H), 6.77 (d, J=8.20 Hz, 1H), 2.36 (s, 3H).
Example 39
Intermediate 16
5-Methyl-2-(phenylthio)aniline
[0398]
[0399] To a solution Intermediate 15 (1.0 g, 4.76 mmol) in MeOH (50 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (5.3 g, 82 mmol). The suspension was stirred at room temperature for 1 hour, and was filtered, and the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 16 (760 mg, 87%) was used in the next reaction without further purification.
[0400] 1 H NMR (300 MHz, CD 3 OD) δ 7.13-7.26 (m, 3H), 6.98-7.11 (m, 3H), 6.68 (d, J=0.59 Hz, 1H), 6.44-6.58 (m, 1H), 2.26 (s, 3H).
Example 40
Compound 24
N-[5-Methyl-2-(phenylsulfanyl)phenyl]-1-benzofuran-2-sulfonamide
[0401]
[0402] To Intermediate 16 (335 mg, 1.56 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (335 mg, 1.56 mmol) and the reaction was stirred at 100° C. for 4 hours, then additional benzofuran-2-sulfonyl chloride (168 mg, 0.78 mmol) was added and the reaction was stirred at 100° C. for 16 hours. 2M NaOH (2 ml) was added to the mixture, and it was heated to 100° C. for 1 hour. The mixture was diluted with water, and the products extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 24 (311 mg, 51%).
[0403] 1 H NMR (300 MHz, CDCl 3 ) δ 7.99 (s, 1H), 7.57-7.67 (m, J=11.72 Hz, 2H), 7.24-7.47 (m, 4H), 6.99-7.07 (m, 3H), 6.83-6.96 (m, 3H), 2.39 (s, 3H).
Example 41
Compound 25
N-[5-Methyl-2-(phenylsulfinyl)phenyl]-1-benzofuran-2-sulfonamide
[0404]
[0405] To a solution of Compound 24 (122 mg, 0.31 mmol) in CH 2 Cl 2 (5 ml) was added mCPBA (62 mg, 0.31 mmol) and the reaction was stirred at 0° C. for 30 min and was concentrated. The residue was purified by flash column chromatography on silica gel (100% EtOAc) to yield Compound 25 (98 mg, 77%).
[0406] 1 H NMR (300 MHz, CDCl 3 ) δ 10.48 (br. s., 1H), 7.60 (d, J=7.91 Hz, 0H), 7.55 (s, 1H), 7.50 (d, J=1.76 Hz, 1H), 7.48 (d, J=1.47 Hz, 1H), 7.38-7.44 (m, 2H), 7.23-7.37 (m, 6H), 6.95 (dd, J=0.88, 7.91 Hz, 1H), 2.35 (s, 3H).
Example 42
Compound 26
N-[5-Methyl-2-(phenylsulfonyl)phenyl]-1-benzofuran-2-sulfonamide
[0407]
[0408] To a solution of Compound 24 (118 mg, 0.30 mmol) in CH 2 Cl 2 (5 ml) was added mCPBA (150 mg, 0.75 mmol) and the reaction was stirred at room temperature for 2 hours and was concentrated. The residue was purified by flash column chromatography on silica gel (100% EtOAc) to yield Compound 26 (117 mg, 92%).
[0409] 1 H NMR (300 MHz, CDCl 3 ) δ 7.76-7.88 (m, 3H), 7.67 (d, J=7.91 Hz, 1H), 7.58 (s, 1H), 7.26-7.53 (m, 7H), 7.02 (d, J=8.21 Hz, 1H), 2.37 (s, 3H).
Example 43
Intermediate 17
(4-Fluoro-2-nitrophenyl)(phenyl)sulfane
[0410]
[0411] To a solution of 1-chloro-4-fluoro-2-nitrobenzene (1.20 g, 6.82 mmol) in MeOH (10 ml) was added benzenethiol (1.0 ML, 10.22 mmol) and NaOH (1.5 ml, 5M) and the reaction was stirred at room temperature for 16 hours, diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 17
[0000] (1.3 g, 80%).
[0412] 1 H NMR (300 MHz, CDCl 3 ) δ 7.94 (dd, J=2.78, 8.35 Hz, 1H), 7.54-7.63 (m, 2H), 7.44-7.52 (m, 3H), 7.03-7.18 (m, 1H), 6.86 (dd, J=4.98, 9.08 Hz, 1H).
Example 44
Intermediate 18
5-Fluoro-2-(phenylthio)aniline
[0413]
[0414] To a solution Intermediate 17 (1.3 g, 5.20 mmol) in MeOH (50 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (8.4 g, 130 mmol). The suspension was stirred at room temperature for 1 hour and was filtered, the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 18 (980 mg, 86%) was used in the next reaction without further purification.
[0415] 1 H NMR (300 MHz, CDCl 3 ) δ 7.35-7.50 (m, 1H), 7.18-7.30 (m, 2H), 7.00-7.17 (m, 3H), 6.37-6.57 (m, 2H), 4.02 (br. s., 2H).
Example 45
Compound 27
N-[5-Fluoro-2-(phenylsulfanyl)phenyl]-1-benzofuran-2-sulfonamide
[0416]
[0417] To Intermediate 18 (980 mg, 4.45 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (962 mg, 4.45 mmol) and the reaction was stirred at 100° C. for 16 hours and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 27 (679 mg, 38%).
[0418] 1 H NMR (300 MHz, CDCl 3 ) δ 8.14 (br.s, 1H), 7.56-7.67 (m, 2H), 7.29-7.54 (m, 5H), 7.00-7.08 (m, 3H), 6.78-6.90 (m, 3H).
Example 46
Compound 28
N-[5-Fluoro-2-(phenylsulfinyl)phenyl]-1-benzofuran-2-sulfonamide
[0419]
[0420] To a solution of Compound 27 (485 mg, 0.71 mmol) in CH 2 Cl 2 (5 ml) was added mCPBA (143 mg, 0.71 mmol) and the reaction was stirred at 0° C. for 30 min, and the solution was concentrated. The residue was purified by flash column chromatography on silica gel (100% EtOAc) to yield Compound 28 (420 mg, 83%).
[0421] 1 H NMR (300 MHz, CDCl) δ 10.73 (br. s., 1H), 7.63 (d, J=7.91 Hz, 1H), 7.39-7.56 (m, 6H), 7.28-7.38 (m, 5H), 6.84 (td, J=2.34, 8.06 Hz, 1H).
Example 47
Compound 29
N-[5-Fluoro-2-(phenylsulfonyl)phenyl]-1-benzofuran-2-sulfonamide
[0422]
[0423] To a solution of Compound 27 (220 mg, 0.55 mmol) in CH 2 Cl 2 (5 ml) was added mCPBA (276 mg, 1.38 mmol) and the reaction was stirred at room temperature for 2 hours and was concentrated. The residue was purified by flash column chromatography on silica gel (100% EtOAc) to yield Compound 29 (170 mg, 72%).
[0424] 1 H NMR (300 MHz, CDCl 3 ) δ 7.97 (dd, J=6.01, 8.94 Hz, 1H), 7.78-7.89 (m, 2H), 7.68 (d, J=7.62 Hz, 1H), 7.29-7.61 (m, 8H), 6.78-6.97 (m, 1H).
Example 48
Intermediate 19
Methyl 2-((4-Chloro-2-nitrophenoxy)methyl)benzoate
[0425]
[0426] To a solution of 4-chloro-2-nitrophenol (541 mg, 3.12 mmol) in DMF (10 ml) was added methyl 2-(bromomethyl)benzoate (714 mg, 3.12 mmol) and K 2 CO 3 (1.3 g, 9.35 mmol). The reaction was stirred at room temperature for 16 hours, diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo. The residue was purified by MPLC to yield Intermediate 19 (959 mg, 96%).
[0427] 1 H NMR (600 MHz, CDCl 3 ) δ 8.08 (dd, J=1.32, 7.78 Hz, 1H), 7.92 (d, J=2.64 Hz, 1H), 7.91 (d, J=7.92 Hz, 1H), 7.59-7.68 (m, 1H), 7.48-7.54 (m, 1H), 7.43 (t, J=7.63 Hz, 1H), 7.20 (d, J=9.10 Hz, 1H), 5.66 (s, 2H), 3.88-3.99 (m, 3H).
Example 49
Intermediate 20
Methyl 2-((2-(Benzofuran-2-sulfonamido)-4-chlorophenoxy)methyl)benzoate
[0428]
[0429] To a solution Intermediate 19 (959 mg, 2.99 mmol) in MeOH (50 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (3.9 g, 60 mmol). The suspension was stirred at room temperature for 1 hour, filtered, and the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 20 (713 mg, 82%) was used in the next reaction without further purification.
[0430] 1 H NMR (600 MHz, CDCl 3 ) δ 8.01 (dd, J=1.32, 7.78 Hz, 1H), 7.61-7.66 (m, 1H), 7.55 (td, J=1.47, 7.63 Hz, 1H), 7.36-7.42 (m, 1H), 6.69-6.74 (m, 2H), 6.59-6.64 (m, 1H), 5.48 (s, 2H), 3.94 (br. s., 2H), 3.89 (s, 3H).
Example 50
Compound 30
Methyl 2-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoate
[0431]
[0432] To Intermediate 20 (329 mg, 1.13 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (244 mg, 1.13 mmol) and the reaction was stirred at 100° C. for 16 hours and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 30 (231 mg, 43%).
[0433] 1 H NMR (600 MHz, CDCl 3 ) δ 7.99-8.07 (m, 1H), 7.58-7.67 (m, 2H), 7.51 (br. s., 1H), 7.33-7.44 (m, 4H), 7.22-7.33 (m, 3H), 6.89-7.05 (m, 1H), 6.71 (dd, J=4.70, 8.80 Hz, 1H), 5.35 (d, J=4.40 Hz, 2H), 3.89 (d, J=4.70 Hz, 3H).
Example 51
Compound 31
2-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoic Acid
[0434]
[0435] To Compound 30 (180 mg, 0.38 mmol) in MeOH (30 ml) was added 5M NaOH (2 ml) and stirred at room temperature for 16 hours. The mixture was acidified with 10% HCl, extracted with EtOAc (×2). The combined organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was recrystallized from minimal MeOH and CH 2 Cl 2 to yield Compound 31 (168 mg, 96%).
[0436] 1 H NMR (600 MHz, CDCl 3 ) δ 8.06 (dd, J=1.32, 7.78 Hz, 1H), 7.58-7.64 (m, 2H), 7.23-7.43 (m, 7H), 7.00 (dd, J=2.64, 8.80 Hz, 1H), 6.72 (d, J=8.80 Hz, 1H), 5.32 (s, 2H).
Example 52
Intermediate 21
Methyl 2-((4-Chloro-2-nitrophenyl)thio)benzoate
[0437]
[0438] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (1.1 g, 6.0 mmol) in MeOH (10 ml) was added methyl 2-mercaptobenzoate (1.0 g, 6.0 mmol) and 4M NaOH (1.5 ml, 6.0 mmol) and the reaction was stirred at room temperature for 2 hours, diluted with H 2 O, and the resulting suspension was filtered and washed with H 2 O to yield Intermediate 21
[0000] as a yellow solid (2.0 g, crude). The crude product was used in the next reaction without further purification.
Example 53
Intermediate 22
Methyl 2-((2-amino-4-chlorophenyl)thio)benzoate hydrochloride salt
[0439]
[0440] To a solution of Intermediate 21 (0.99 g, 3.1 mmol) in MeOH (15 ml) and CH 2 Cl 2 (15 ml) was added saturated aqueous NH 4 Cl (20 ml) and zinc dust (5.0 g, 77 mmol). The suspension was stirred at room temperature for 30 minutes and was filtered, the filtrate was extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was dissolved in Et 2 O, and 2M HCl in Et 2 O (4 ml) was added. The resulting suspension was filtered and the solid was washed with Et 2 O (×3) to yield Intermediate 22 as a white solid (0.75 g, 75%).
[0441] 1H NMR (METHANOL-d4) δ: 8.01 (d, J=7.6 Hz, 1H), 7.49 (d, J=8.2 Hz, 1H), 7.31-7.41 (m, 1H), 7.20-7.28 (m, 2H), 7.15 (dd, J=8.5, 1.8 Hz, 1H), 6.78 (d, J=7.9 Hz, 1H), 3.93 (s, 3H).
Example 54
Compound 32
2-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenyl}sulfanyl)benzoic Acid
[0442]
[0443] To Intermediate 22 (0.75 g, 2.27 mmol) in pyridine (4 ml) was added benzofuran-2-sulfonyl chloride (493 mg, 2.27 mmol) and the reaction was stirred at room temperature for 16 hours, when additional benzofuran-2-sulfonyl chloride (250 mg, 1.15 mmol) was added. The reaction was continued for 24 hours and was concentrated in vacuo. The residue was dissolved in MeOH and was treated with 4M NaOH (3 ml) at 100° C. for 15 minutes, and cooled, and acidified with 6M HCl, and the products were extracted with EtOAc (×2). The combined organic layers were washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was triturated with 10% MeOH in CH 2 Cl 2 to yield Compound 32 as a pinkish white solid (0.75 g, 66%).
[0444] 1H NMR (acetone) δ: 11.56 (br. s., 1H), 9.21 (s, 1H), 7.99 (dd, J=7.8, 1.6 Hz, 1H), 7.88 (d, J=2.3 Hz, 1H), 7.74 (dt, J=7.9, 1.0 Hz, 1H), 7.57 (d, J=3.8 Hz, 1H), 7.56 (d, J=3.5 Hz, 1H), 7.51 (ddd, J=8.4, 7.1, 1.2 Hz, 1H), 7.45 (dd, J=8.2, 0.9 Hz, 1H), 7.37 (ddd, J=7.9, 7.0, 0.9 Hz, 1H), 7.33 (dd, J=8.2, 2.3 Hz, 1H), 7.11 (td, J=7.5, 1.2 Hz, 1H), 6.95-7.00 (m, 1H), 6.41 (dd, J=8.1, 1.0 Hz, 1H).
Example 55
Intermediate 23
Methyl 3-((4-Chloro-2-nitrophenyl)thio)benzoate
[0445]
[0446] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (1.0 g, 5.6 mmol) in MeOH (10 ml) was added methyl 3-mercaptobenzoate (0.95 g, 5.6 mmol) and 4M NaOH (1.4 ml, 5.6 mmol) and the reaction was stirred at room temperature for 2 hours, diluted with H 2 O, and the resulting suspension was filtered and washed with H 2 O to yield Intermediate 23
[0000] as a yellow solid (1.9 g, 100%).
[0447] 1H NMR (CHLOROFORM-d) δ: 8.21-8.26 (m, 2H), 8.15-8.20 (m, 1H), 7.73-7.78 (m, 1H), 7.56-7.61 (m, 1H), 7.31 (dt, J=8.8, 2.1 Hz, 1H), 6.77 (dd, J=8.8, 1.8 Hz, 1H), 3.94 (s, 3H).
Example 56
Intermediate 24
Methyl 3-((2-Amino 4-chlorophenyl)thio)benzoate
[0448]
[0449] To a solution of Intermediate 23 (0.83 g, 2.6 mmol) in MeOH (15 ml) and CH 2 Cl 2 (15 ml) was added saturated aqueous NH 4 Cl (20 ml) and zinc dust (4.2 g, 64 mmol). The suspension was stirred at room temperature for 1 hour and was filtered, and the filtrate was extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product Intermediate 24 (0.77 g, 100%) was used in the next reaction without further purification.
[0450] 1H NMR (CHLOROFORM-d) δ: 7.77-7.82 (m, 2H), 7.38 (d, J=8.2 Hz, 1H), 7.27-7.32 (m, 1H), 7.19 (ddd, J=7.9, 2.1, 1.2 Hz, 1H), 6.80 (d, J=2.3 Hz, 1H), 6.74 (dd, J=8.2, 2.1 Hz, 1H), 3.89 (s, 3H).
Example 57
Compound 33
3-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenyl}sulfanyl)benzoic Acid
[0451]
[0452] To Intermediate 24 (0.76 g, 2.6 mmol) in pyridine (4 ml) was added benzofuran-2-sulfonyl chloride (0.56 g, 2.6 mmol) and the reaction was stirred at room temperature for 16 hours, when additional benzofuran-2-sulfonyl chloride (0.28 g, 1.3 mmol) was added. The reaction was continued for 24 hours and was concentrated in vacuo. The residue was taken up in MeOH and was treated with 4M NaOH (3 ml) at 100° C. for 15 minutes, and cooled, and acidified with 6M HCl, and extracted with EtOAc (×2). The combined organic layers were washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-50% EtOAc in hexanes) to yield Compound 33 (0.75 g, 63%).
[0453] 1H NMR (acetone) δ: 7.79 (dt, J=8.0, 1.3 Hz, 1H), 7.73 (dt, J=7.9, 1.0 Hz, 1H), 7.71 (d, J=2.3 Hz, 1H), 7.69 (t, J=1.6 Hz, 1H), 7.46-7.53 (m, 3H), 7.32-7.37 (m, 2H), 7.24-7.30 (m, 2H), 7.17 (ddd, J=7.9, 2.1, 1.2 Hz, 1H).
Example 58
Intermediate 25
Methyl 4-((4-Chloro-2-nitrophenyl)thio)benzoate
[0454]
[0455] To a solution of 4-chloro-1-fluoro-2-nitrobenzene (1.0 g, 5.6 mmol) in MeOH (10 ml) was added methyl 4-mercaptobenzoate (0.95 g, 5.6 mmol) and 4M NaOH (1.4 ml, 5.6 mmol) and the reaction was stirred at room temperature for 2 hours, diluted with H 2 O, and the resulting suspension was filtered and washed with H 2 O to yield Intermediate 25
[0456] As a yellow solid (1.4 g, 78%).
[0457] 1H NMR (CHLOROFORM-d) δ: 8.22 (s, 1H), 8.12 (d, J=7.9 Hz, 2H), 7.63 (d, J=8.2 Hz, 2H), 7.34 (dd, J=8.8, 2.3 Hz, 1H), 6.88 (d, J=8.8 Hz, 1H), 3.97 (s, 3H).
Example 59
Intermediate 26
Methyl 4-((2-Amino-4-chlorophenyl)thio)benzoate
[0458]
[0459] To a solution of Intermediate 25 (0.69 g, 2.1 mmol) in MeOH (15 ml) and CH 2 Cl 2 (15 ml) was added saturated aqueous NH 4 Cl (20 ml) and zinc dust (3.5 g, 54 mmol). The suspension was stirred at room temperature for 1 hour and was filtered, and the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, and dried over Na 2 SO 4 , and concentrated in vacuo. The crude product Intermediate 26 (0.63 g, 99%) was used in the next reaction without further purification.
[0460] 1H NMR (CHLOROFORM-d) δ: 7.87 (d, J=8.5 Hz, 2H), 7.37 (d, J=8.2 Hz, 1H), 7.06 (d, J=8.5 Hz, 2H), 6.82 (d, J=2.3 Hz, 1H), 6.75 (dd, J=8.2, 2.3 Hz, 1H), 4.36 (br. s., 2H), 3.88 (s, 3H).
Example 60
Compound 34
4-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenyl}sulfanyl)benzoic Acid
[0461]
[0462] To Intermediate 26 (0.62 g, 2.1 mmol) in pyridine (4 ml) was added benzofuran-2-sulfonyl chloride (0.46 g, 2.1 mmol) and the reaction was stirred at room temperature for 16 hours, when additional benzofuran-2-sulfonyl chloride (0.23 g, 1.1 mmol) was added. The reaction was continued for 24 hours and was concentrated in vacuo. The residue was taken up in MeOH and was treated with 4M NaOH (3 ml) at 100° C. for 15 minutes, and cooled, and acidified with 6M HCl, and the products extracted with EtOAc (×2). The combined organic layers were washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-50% EtOAc in hexanes) followed by re-crystallization from minimal acetone and CH 2 Cl 2 to yield Compound 34 (0.23 g, 24%).
[0463] 1H NMR (acetone) δ: 11.17 (br. s., 1H), 9.23 (br. s., 1H), 7.78 (d, J=2.1 Hz, 1H), 7.69-7.75 (m, 3H), 7.54 (s, 1H), 7.45-7.51 (m, 3H), 7.32-7.36 (m, 2H), 6.95-6.98 (m, 2H).
Example 61
Intermediate 27
Methyl 3-((4-Chloro-2-nitrophenoxy)methyl)benzoate
[0464]
[0465] To a solution of 4-chloro-2-nitrophenol (611 mg, 3.52 mmol) in DMF (10 ml) was added methyl 3-(bromomethyl)benzoate (807 mg, 3.52 mmol) and K 2 CO 3 (1.46 g, 10.57 mmol) and the reaction was stirred at room temperature for 16 hours, and diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, and dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 27 (959 mg, 96%).
[0466] 1 H NMR (600 MHz, CDCl 3 ) δ 8.08 (s, 1H), 8.02 (d, J=7.92 Hz, 1H), 7.87 (d, J=2.64
[0467] Hz, 1H), 7.69 (d, J=7.63 Hz, 1H), 7.46-7.51 (m, 2H), 7.06 (d, J=8.80 Hz, 1H), 5.26 (s, 2H), 3.94 (s, 3H).
Example 62
Intermediate 28
Methyl 3-((2-(Benzofuran-2-sulfonamido)-4-chlorophenoxy)methyl)benzoate
[0468]
[0469] To a solution Intermediate 27 (630 mg, 1.96 mmol) in MeOH (20 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (2.6 g, 39 mmol). The suspension was stirred at room temperature for 1 hour and was filtered, and the filtrate was extracted with EtOAc (×2). The organic layer was washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 28 (561 mg, 98%) was used in the next reaction without further purification.
[0470] 1 H NMR (600 MHz, CDCl 3 ) δ 8.09 (dt, J=0.88, 1.76 Hz, 1H), 8.01 (d, J=7.34 Hz, 1H), 7.61 (d, J=7.63 Hz, 1H), 7.47 (t, J=7.78 Hz, 1H), 6.69-6.73 (m, 2H), 6.63 (dd, J=2.64, 8.51 Hz, 1H), 5.09 (s, 2H), 3.93 (s, 3H).
Example 63
Compound 35
Methyl 3-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoate
[0471]
[0472] To Intermediate 28 (561 mg, 1.93 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (416 mg, 1.93 mmol) and the reaction was stirred at 100° C. for 16 hours and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 35 (651 mg, 72%).
[0473] 1 H NMR (600 MHz, CDCl 3 ) δ 8.00-8.06 (m, 1H), 7.97 (d, J=0.88 Hz, 1H), 7.60-7.67 (m, 2H), 7.42-7.49 (m, 2H), 7.36-7.40 (m, 2H), 7.28-7.35 (m, 2H), 6.99 (dd, J=2.49, 8.66 Hz, 1H), 6.72 (d, J=8.80 Hz, 1H), 4.95 (s, 2H), 3.95 (s, 3H).
Example 64
Compound 36
3-({2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}methyl)benzoic Acid
[0474]
[0475] To Compound 35 (506 mg, 1.07 mmol) in MeOH (30 ml) was added 5M NaOH (2 ml) and the solution stirred at room temperature for 16 hours. The mixture was acidified with 10% HCl, and extracted with EtOAc (×2). The combined organic layers were washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was recrystallized from minimal MeOH and CH 2 Cl 2 to yield Compound 36 (484 mg, 98%).
[0476] 1 H NMR (600 MHz, DMSO-d 6 ) δ 13.01 (br. s., 1H), 10.57 (s, 1H), 7.78-7.84 (m, 2H), 7.62-7.67 (m, 1H), 7.42-7.47 (m, 2H), 7.37-7.42 (m, 2H), 7.31-7.35 (m, 1H), 7.27-7.31 (m, 2H), 7.24 (dd, J=2.35, 8.80 Hz, 1H), 7.00 (d, J=8.80 Hz, 1H), 4.87 (s, 2H).
Example 65
Intermediate 29
Isochroman-1-one
[0477]
[0478] To isochroman (3 g, 22.4 mmol) in xylene (30 ml) was added SeO 2 (2.48 g, 22.4 mmol) and the mixture stirred at 140° C. for 20 hours, and then additional SeO 2 (2.48 g, 22.4 mmol) was added and the reaction heated for 24 hours. The mixture was cooled down to room temperature, SeO 2 was filtered away and xylene was removed in vacuo. The crude residue was purified by flash column chromatography on silica gel (0-20% EtOAc in hexanes) to yield Intermediate 29 (2.69 g, 81%) as a pale red liquid.
[0479] 1 H NMR (600 MHz, CDCl 3 ) δ 8.10 (dd, J=0.88, 7.63 Hz, 1H), 7.54 (td, J=1.47, 7.48 Hz, 1H), 7.37-7.41 (m, 1H), 7.24-7.28 (m, 1H), 4.51-4.55 (m, 2H), 3.06 (t, J=6.02 Hz, 2H).
Example 66
Intermediate 30
2-(2-Hydroxyethyl)benzoic Acid
[0480]
[0481] To a solution of Intermediate 29 (2.69 g, 17.97 mmol) in Et 2 O anhydrous (50 ml) was added powdered KOH (2.01 g, 35.94 mmol), and the reaction was stirred at room temperature for 12 hours. The ether solution was decanted, the residue solid was washed with ether, then dissolved in water. The aqueous solution was acidified with 10% HCl and then extracted with ether (×3). The combine ether layers was dried over Na 2 SO 4 and concentrated in vacuo to yield crude Intermediate 30 (−2 g) which was used quickly in the next step without purification.
[0482] 1 H NMR (600 MHz, DMSO-d 6 ) δ 12.81 (br. s., 1H), 7.74 (dd, J=1.17, 7.63 Hz, 1H), 7.41-7.46 (m, 1H), 7.26-7.34 (m, 2H), 4.61 (br. s., 1H), 3.56 (t, J=7.04 Hz, 2H), 3.06 (t, J=7.04 Hz, 2H).
Example 67
Intermediate 31
Methyl 2-(2-Hydroxyethyl)benzoate
[0483]
[0484] To crude Intermediate 30 (˜2 g, 12.0 mmol) in anhydrous THF (12 ml) and MeOH (12 ml) under N 2 atmosphere at 0° C. was added TMSCHN 2 (7.8 ml, 15.66 mmol) via syringe until a persistent yellowish color was observed and development of gas ceased. The solvent was removed on rotary evaporator under vacuum to yield crude Intermediate 31 as a colorless oil.
Example 68
Intermediate 32
Methyl 2-(2-(tosyloxy)ethyl)benzoate
[0485]
[0486] To crude Intermediate 31 in anhydrous CHCl 3 (25 ml) under N 2 atmosphere at 0° C. was added TsCl (4.5 g, 24.0 mmol) in CHCl 3 (10 ml) followed by addition of pyridine (3 ml, 36 mmol) immediately. The reaction was warmed up to room temperature and stirred for 12 hours, and diluted with water, and the products extracted with EtOAc. The combined organic layers were washed with brine, and dried over Na 2 SO 4 and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (0-20% EtOAc in hexanes) to yield Intermediate 32 (2.2 g, 58%) as a clear oil.
[0487] 1 H NMR (600 MHz, CDCl 3 ) δ 7.88 (dd, J=1.32, 7.78 Hz, 1H), 7.65 (d, J=8.51 Hz, 2H), 7.37-7.46 (m, 1H), 7.28-7.32 (m, 1H), 7.19-7.26 (m, 3H), 4.29 (t, J=6.60 Hz, 2H), 3.83 (s, 3H), 3.32 (t, J=6.60 Hz, 2H), 2.42 (s, 3H).
Example 69
Intermediate 33
Methyl 2-(2-Bromoethyl)benzoate
[0488]
[0489] To Intermediate 32 (1.95 g, 5.84 mmol) in acetone (10 ml) was added LiBr (1.01 g, 11.68 mmol), and the mixture was heated to reflux for 5 hours under N 2 atmosphere. The solvent was removed, and the residue diluted with water, and the products extracted with CH 2 Cl 2 . The combined organic layers were washed with brine, and dried over Na 2 SO 4 and concentrated in vacuo. The crude Intermediate 33 (1.38 g) was used for next step without purification.
[0490] 1 H NMR (600 MHz, CDCl 3 ) δ 7.96 (dd, J=1.47, 7.92 Hz, 1H), 7.44-7.51 (m, 1H), 7.28-7.37 (m, 2H), 3.91 (s, 3H), 3.64 (t, J=7.34 Hz, 2H), 3.51 (t, J=7.34 Hz, 2H).
Example 70
Intermediate 34
Methyl 2-(2-(4-Chloro-2-nitrophenoxy)ethyl)benzoate
[0491]
[0492] To a solution of 4-chloro-2-nitrophenol (985 mg, 5.68 mmol) in DMF (10 ml) was added crude Intermediate 33 (1.38 g, 5.68 mmol) and K 2 CO 3 (3.9 g, 28.4 mmol) and the reaction was stirred at 90° C. for 16 hours, diluted with H 2 O, and the resulting solution was extracted with EtOAc and washed with brine, dried over Na 2 SO 4 and concentrated in vacuo, followed by MPLC purification to yield Intermediate 34 (520 mg, 27% for 2 steps).
[0493] 1 H NMR (600 MHz, CDCl 3 ) δ 7.96 (dd, J=1.17, 7.92 Hz, 1H), 7.79 (d, J=2.64 Hz, 1H), 7.47-7.53 (m, 1H), 7.41-7.46 (m, 2H), 7.33 (td, J=1.17, 7.63 Hz, 1H), 7.07 (d, J=8.80 Hz, 1H), 4.39 (t, J=6.31 Hz, 2H), 3.91 (s, 3H), 3.49 (t, J=6.31 Hz, 2H).
Example 71
Intermediate 35
Methyl 2-(2-(2-Amino-4-chlorophenoxy)ethyl)benzoate
[0494]
[0495] To a solution Intermediate 34 (685 mg, 2.04 mmol) in MeOH (20 ml) was added saturated aqueous NH 4 Cl (2 ml) and zinc dust (3.3 g, 51 mmol). The suspension was stirred at room temperature for 1 hour and was filtered, the filtrate was extracted with EtOAc (×2). The combined organic layers were washed with brine, and dried over Na 2 SO 4 , and concentrated in vacuo. The crude Intermediate 35 (557 mg, 89%) was used in the next reaction without further purification.
[0496] 1 H NMR (600 MHz, CDCl 3 ) δ 7.94 (dd, J=0.88, 7.63 Hz, 1H), 7.47 (dd, J=1.17, 7.63 Hz, 1H), 7.36 (d, J=7.63 Hz, 1H), 7.32 (td, J=1.17, 7.63 Hz, 1H), 6.69 (d, J=8.51 Hz, 1H), 6.65 (d, J=2.35 Hz, 1H), 6.60-6.64 (m, 1H), 4.23 (t, J=6.60 Hz, 2H), 3.90 (s, 3H), 3.79 (br. s., 2H), 3.49 (t, J=6.46 Hz, 2H).
Example 72
Compound 37
Methyl 2-(2-{2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}ethyl)benzoate
[0497]
[0498] To Intermediate 35 (555 mg, 1.82 mmol) in pyridine (5 ml) was added benzofuran-2-sulfonyl chloride (393 mg, 1.82 mmol) and the reaction was stirred at 100° C. for 16 hours and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (0-30% EtOAc in hexanes) to yield Compound 37 (634 mg, 88%).
[0499] 1 H NMR (600 MHz, CDCl 3 ) δ 7.97 (dd, J=1.17, 7.92 Hz, 1H), 7.60-7.64 (m, 1H), 7.55 (d, J=2.64 Hz, 1H), 7.53 (td, J=1.47, 7.48 Hz, 1H), 7.40-7.48 (m, 3H), 7.35 (td, J=1.17, 7.63 Hz, 1H), 7.28-7.32 (m, 2H), 6.95 (dd, J=2.49, 8.66 Hz, 1H), 6.69 (d, J=8.80 Hz, 1H), 4.13 (t, J=6.46 Hz, 2H), 3.92 (s, 3H), 3.36 (t, J=6.31 Hz, 2H).
Example 73
Compound 38
2-(2-{2-[(1-Benzofuran-2-ylsulfonyl)amino]-4-chlorophenoxy}ethyl)benzoic Acid
[0500]
[0501] To Compound 37 (505 mg, 1.04 mmol) in MeOH (30 ml) was added 5M NaOH (2 ml) and the reaction was stirred at room temperature for 16 hours. The mixture was acidified with 10% HCl, and extracted with EtOAc (×2). The combined organic layers were washed with brine, and dried over Na 2 SO 4 , and concentrated in vacuo. The crude product was recrystallized from minimal MeOH and CH 2 Cl 2 to yield Compound 38 (454 mg, 93%).
[0502] 1 H NMR (600 MHz, CDCl 3 ) δ 8.07 (d, J=7.92 Hz, 1H), 7.67 (br. s., 1H), 7.61 (d, J=7.92 Hz, 1H), 7.55 (td, J=1.17, 7.48 Hz, 1H), 7.52 (d, J=2.35 Hz, 1H), 7.35-7.46 (m, 3H), 7.27-7.35 (m, 3H), 6.93 (dd, J=2.49, 8.66 Hz, 1H), 6.65 (d, J=8.80 Hz, 1H), 4.10 (t, J=6.46 Hz, 2H), 3.45 (t, J=6.02 Hz, 2H).
Biological Data
[0503] HEK-Gqi5 cells stably expressing CCR2 were cultured in DMEM high glucose, 10% FBS, 1% PSA, 400 μg/ml geneticin and 50 μg/ml hygromycin. Appropriate positive control chemokines (MCP-1, MIP1A or RANTES) was used as the positive control agonist for screening compound-induced calcium activity assayed on the FLIPR Tetra . The drug plates were prepared in 384-well microplates using the EP3 and the MultiPROBE robotic liquid handling systems. Compounds were synthesized and tested for CCR2 activity.
[0000]
TABLE 1
shows activity: CCR2 receptor (IC 50 ) nM
CCR2
ANTAG-
CCR2 IC50
ONISM
IUPAC Name
(nM)
(%)
N-(5-chloro-2-methoxyphenyl)-1-benzofuran-2-
512
97
sulfonamide
N-(5-chloro-2-methylphenyl)-1-benzofuran-2-
359
84
sulfonamide
N-[5-chloro-2-(trifluoromethoxy)phenyl]-1-
195
95
benzofuran-2-sulfonamide
methyl 2-[(1-benzofuran-2-ylsulfonyl)amino]-4-
1376
95
chlorobenzoate
N-(5-chloro-2-ethoxyphenyl)-1-benzofuran-2-
1662
73
sulfonamide
N-(5-chloro-2-ethynylphenyl)-1-benzofuran-2-
117
93
sulfonamide
N-{5-chloro-2-[(4-oxopiperidin-1-
110
93
yl)carbonyl]phenyl}-1-benzofuran-2-sulfonamide
N-[5-chloro-2-(morpholin-4-ylcarbonyl)phenyl]-
569
84
1-benzofuran-2-sulfonamide
N-{5-chloro-2-[(2-methylpyridin-3-
365
96
yl)oxy]phenyl}-1-benzofuran-2-sulfonamide
methyl 2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-
1018
98
4-chlorophenoxy}benzoate
2-{2-[(1-benzofuran-2-ylsulfonyl)amino]-4-
60
97
chlorophenoxy}benzoic acid
N-[5-chloro-2-(phenylsulfanyl)phenyl]-1-
124
90
benzofuran-2-sulfonamide
N-[5-chloro-2-(phenylsulfonyl)phenyl]-1-
1971
78
benzofuran-2-sulfonamide
N-[5-chloro-2-(phenylsulfinyl)phenyl]-1-
6
105
benzofuran-2-sulfonamide
2-[(1-benzofuran-2-ylsulfonyl)amino]-4-chloro-
328
95
N-phenylbenzamide
N-(5-chloro-2-cyanophenyl)-1-benzofuran-2-
409
102
sulfonamide
N-[5-chloro-2-(phenylacetyl)phenyl]-1-
183
79
benzofuran-2-sulfonamide
N-{5-chloro-2-[(1Z)-N-methoxy-2-
nd
76
phenylethanimidoyl]phenyl}-1-benzofuran-2-
sulfonamide
N-{5-chloro-2-[(1Z)-N-hydroxy-2-
nd
72
phenylethanimidoyl]phenyl}-1-benzofuran-2-
sulfonamide
N-[2-(benzyloxy)-5-chlorophenyl]-1-benzofuran-
1629
87
2-sulfonamide
N-[5-chloro-2-(phenylethynyl)phenyl]-1-
nd
30
benzofuran-2-sulfonamide
N-[5-chloro-2-(2-phenylethyl)phenyl]-1-
nd
84
benzofuran-2-sulfonamide
N-[5-methyl-2-(phenylsulfanyl)phenyl]-1-
nd
41
benzofuran-2-sulfonamide
N-[5-methyl-2-(phenylsulfinyl)phenyl]-1-
2875
92
benzofuran-2-sulfonamide
N-[5-methyl-2-(phenylsulfonyl)phenyl]-1-
nd
38
benzofuran-2-sulfonamide
N-[5-fluoro-2-(phenylsulfanyl)phenyl]-1-
nd
74
benzofuran-2-sulfonamide
N-[5-fluoro-2-(phenylsulfinyl)phenyl]-1-
317
91
benzofuran-2-sulfonamide
N-[5-fluoro-2-(phenylsulfonyl)phenyl]-1-
2618
82
benzofuran-2-sulfonamide
2-({2-[(1-benzofuran-2-ylsulfonyl)amino]-4-
27
99
chlorophenoxy}methyl)benzoic acid | The present invention relates to novel benzofuran-2-sulfonamide derivatives, processes for preparing them, pharmaceutical compositions containing them and their use as pharmaceuticals as modulators of chemokine receptors. | 2 |
FIELD OF THE INVENTION
The present invention relates to a surge protection method and apparatus in which the capacity of a thrust bearing of a compressor is prevented from being exceeded during a surge event. More particularly, the present invention relates to such a method and apparatus in which a biasing force is exerted on an impeller of a compressor and through the compressor shaft to the thrust bearing, during normal operation of the compressor, by producing a force difference between an impeller eye side force and a back disk force exerted on the impeller through the back disk seal that increases the overload margin between the thrust bearing capacity and a surge force occurring during the surge event.
BACKGROUND OF THE INVENTION
Centrifugal compressors are well known in the art and are used in many applications to compress a gas from a lower pressure to a higher pressure. The gas at the lower pressure enters an inlet of the centrifugal compressor and is compressed to a higher pressure by being accelerated by a rotating impeller and then sent into a diffuser surrounding the impeller, in which additional pressure is recovered by decelerating the gas. The gas is discharged from the diffuser to a volute and from the volute to an outlet thereof at the higher pressure.
In a centrifugal compressor, a high pressure seal is provided on the back of the impeller or in other words on the side of the impeller opposite to the inlet. This seal is typically a labyrinth type of seal that has a smaller diameter than the outer diameter of the impeller as defined by the outer rim thereof. High pressure gas seeps through the outer rim during operation of the compressor and such seal prevents this high pressure gas from pressurizing the entire back of the impeller. A lower pressure gas from a location such as the compressor inlet or an even lower pressure source if available, is introduced into a cavity formed at the back of the compressor, between the motor shaft driving the impeller and the high pressure seal. Leakage from the cavity is prevented by a shaft seal on the motor shaft driving the impeller. The pressure within this cavity acts on the resulting inner annular area behind the impeller along with the high pressure acting in the outer annular area between the outer rim of the impeller and the high pressure seal. The sum of these two forces produce a force that is known as the back disk force on the impeller. Acting inwardly of the impeller, is an eye side force produced by the onrush of gas entering the impeller and acting on the surface of the impeller facing to the inlet. In the prior art, the high pressure seal is sized so that during design conditions the eye side force is in balance with the back disk force.
Compressors are designed to operate within an operating envelope that can be plotted in what is referred to as a compressor map of pressure ratio between outlet pressure and inlet pressure versus flow rate through the compressor. On such a plot, a peak or best efficiency operating line is plotted in which for a given flow rate and pressure ratio, the energy consumption of the compressor is at a minimum. The plot also has another dimension of specific speeds which cross the peak efficiency operating line. If the pressure ratio falls within the compressor for a given speed, a point is ultimately reached when the compressor goes into what is referred to as surge. A surge event is therefore, produced by flow rate through the compressor falling below a minimum flow required at a given speed of the impeller of the compressor that is necessary to maintain stable operation. From a viewpoint taken from the impeller, a surge event has two phases. In a first phase there is a sudden loss of discharge pressure within the impeller flow passages arising from aerodynamic instability in the impeller. This results in a decrease in the eye side pressure. However, the back disk force, remains high due to fluidic system inertial effects. This results in a large axial force on the impeller driving the impeller towards the inlet. The second phase of the surge event is produced by the high pressure back disk pressure bleeding down to lower eye side pressure, resulting in the eye side force overcoming the weakened back disk force. This produces a large axial force driving the impeller away from the inlet. The frequency at which these forces are developed is quite high resulting in destruction of the compressor starting with an overload of the thrust bearing.
The forces developed during a surge event can be computed or measured and the thrust bearings in the compressor can be designed with an overload margin to absorb these forces and prevent damage to the compressor. However, there has been the increasing use of what are referred to as oil-free bearings in centrifugal compressors. These oil free bearings are either electromagnetic bearings or aerodynamic bearings. In electromagnetic bearings, the motor shaft is suspended in both radial and axial directions by means of a magnetic force. However, such oil-free bearings when applied to the thrust bearing are less able to adsorb the large axial forces that occur during a surge event than conventional bearings that are lubricated with oil. Thus, the overload margins that can be provided by oil-free bearings are less than those that can be provided by conventional bearings. As such, during a surge event, the thrust bearing will be unable to absorb the forces and back-up-, bearings or bushings will be contacted to adsorb the force. The problem with this is that back-up bearings or bushings can only be subjected to a predefined small number of usages during these surge events. After this predetermined number, the compressor will have to be taken off-line for maintenance to replace the back-up bearings or bushings.
The problems outlined above with respect to oil-free bearings have therefore, limited their use in large compressor applications such as air separation plants in which such bearings would otherwise have the advantage of not contaminating the feed to the plant with oil, having much lower frictional losses, and will require less maintenance than conventional oil lubricated bearings. In an application such as an air separation plant, if a compressor is taken off-line, the plant will not function. Unplanned outages in any large installation will in any case result in financial hardship to the plant operator.
As will be discussed, unlike the prior art, the present invention provides a method and apparatus in which the impeller is preloaded with a biasing force that is larger than that required to simply balance impeller eye side and back disk forces during normal operation of the compressor. This preload force is used to increase an overload margin of the bearings that could be exceeded during a surge event and thus, is particularly applicable to a centrifugal compressor using oil-free bearings.
SUMMARY OF THE INVENTION
The present invention provides a method of inhibiting a thrust bearing capacity of a compression system from being exceeded during a surge event. In accordance with such method, the thrust bearing is biased with a biasing force acting in one of two opposite axial directions of a compressor shaft. In such a compressor, the compressor shaft is connected to the thrust bearing and to an impeller of at least one compressor that is in turn provided with a back disk seal. The compression shaft is driven by a driver to drive the impeller through rotation of the compressor shaft and the compression system has at least one stage of compression provided by the at least one compressor. The thrust bearing has a first thrust bearing capacity and a second trust bearing capacity to absorb axial loads acting upon the thrust bearing in the two opposite axial directions of the compressor shaft, respectively. Such thrust bearing is configured such that a first overload margin exists between the first thrust bearing capacity and a first surge force and a second overload margin exists between the second thrust bearing capacity and a second surge force. The first surge force and the second surge force act in the two opposite axial directions and are created during the surge event. The biasing force is exerted on the impeller and through the compressor shaft to the thrust bearing, during normal operation of the compression system, by producing a force difference between an impeller eye side force and a back disk force exerted on the impeller opposite to the eye side force. The back disk force is exerted by a high pressure outer annular region and a low pressure inner annular region of the impeller that is separated by the back disk seal. The biasing force increases one of the first overload margin and the second overload margin such that the first overload margin and the second overload margin are no less than about twenty-five percent of the first through bearing capacity and the second thrust bearing capacity, respectively.
Although the increase of one of the overload margins will be at the expense of the other of the overload margins of the thrust bearing, the largest surge force can thereby be compensated for to increase the ability of the thrust bearing to absorb surge forces. In this regard, at a minimum, the overload margins twenty-five percent of the thrust bearing capacities. As can be appreciated, even larger margins are desirable if possible, for example, fifty percent. Although the present invention is not limited to the use of oil-free bearings as the invention would in fact be advantageous even in the case of the use of oil free bearings, it has particular application to magnetic and aerodynamic bearings that have limited overload margins. This increase in the ability of the thrust bearing to adsorb such surge forces allows the use of such oil-free bearings in large-scale compressor applications and in applications where continued operation of the compressor is particularly critical.
The driver can be an electric motor and the compressor shaft can be a motor shaft protruding from the electric motor. In such case, the thrust bearing is part of the electric motor. Further, the thrust bearing can be a magnetic bearing.
The at least one compressor can comprise a first compressor and a second compressor connected at opposite ends of the motor shaft and in flow communication with each other such that least two successive compression stages are provided in the compression system. In such case, the force difference is produced by a difference between the eye side force and the back disk force of at least one of the first compressor and the second compressor. The at least one compressor can be an upstream compression stage of a plurality of compression stages of the compression system. In such case, the low pressure region is in flow communication with an outlet or an inlet of one other compressor of an upstream compression stage of the plurality of compression stages and is pressurized by a bleed stream from the one other compressor.
The present invention also provides an apparatus for inhibiting a thrust bearing capacity of a compression system from being exceeded during a surge event. In such apparatus a thrust bearing is biased with a biasing force acting in one of two opposite axial directions of a compressor shaft connected to the thrust bearing and to an impeller of at least one compressor having a back disk seal. The compression shaft is driven by a driver to drive the impeller through rotation of the compressor shaft and the compression system has at least one stage of compression provided by the at least one compressor. The thrust bearing has a first thrust bearing capacity and a second trust bearing capacity to absorb axial loads acting upon the thrust bearing in the two opposite axial directions of the compressor shaft, respectively. The thrust bearing is configured such that a first overload margin exists between the first thrust bearing capacity and a first surge force and a second overload margin exists between the second thrust bearing capacity and a second surge force. The first surge force and the second surge force act in the two opposite axial directions and created during the surge event. The back disk seal is sized in a radial direction of the compressor shaft such the biasing force is generated by a force difference during normal operation of the compression system. The biasing force is produced by a force difference between an impeller eye side force and a back disk force exerted on the impeller, opposite to the eye side force, by a high pressure outer annular region and a low pressure inner annular region separated by the back disk seal of the impeller. The force difference is transmitted from the impeller and through the compressor shaft to the thrust bearing and increases one of the first overload margin and the second overload margin such that the first overload margin and the second overload margin are no less than about twenty-five percent of the first thrust bearing capacity and the second thrust bearing capacity, respectively.
The driver can be an electric motor, the compressor shaft can be a motor shaft protruding from the electric motor and the thrust bearing can be part of the electric motor. Further, the thrust bearing can be one of a magnetic bearing.
The at least one compressor can comprise a first compressor and a second compressor connected at opposite ends of the motor shaft and in flow communication with each other such that least two successive compression stages are provided in the compression system. The force difference is produced by a difference between the eye side force and the back disk force of at least one of the first compressor and the second compressor. The at least one compressor can be a downstream compression stage of a plurality of compression stages of the compression system. The low pressure region is in flow communication with an outlet or an inlet of one other compressor of an upstream compression stage of the plurality of compression stages and is pressurized by a bleed stream from the one other compressor.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out the subject matter that applicants regard as their invention, it is believed that invention will be better understood when taken in connection with the accompanying drawings in which:
FIG. 1 is a schematic, sectional view of a compression system in accordance with the present invention that incorporates two compression stages;
FIG. 2 is a schematic, fragmentary view of FIG. 1 that illustrates the eye side and back disk forces developed in each of the compression stages;
FIG. 3 is a schematic, fragmentary view of FIG. 1 illustrating the areas at which the eye side and back disk forces are developed on an impeller in the first stage of compression;
FIG. 4 is schematic diagram of the overload margins and the forces to which an impeller is subjected to in a compressor of the prior art;
FIG. 5 is a schematic diagram of the of the overload margins and the forces to which an impeller is subjected to in a compressor of the present invention; and
FIG. 6 is a schematic diagram of a compression system of the present invention in which an upstream compression stage is used to help provide the biasing force on the impeller in accordance with the present invention.
DETAILED DESCRIPTION
With reference to FIG. 1 , a compression system 1 is illustrated having two successive compression stages provided with two compressors 2 and 3 , respectively, that are driven by an electric motor 4 . Compressors 2 and 3 are centrifugal compressors. Compressor 2 compresses a gas, for instance air, from a low pressure to an intermediate pressure and compressor 3 further compresses the gas from the intermediate pressure to a yet higher pressure. Consequently compressor 3 has a higher outlet pressure than compressor 2 . Although not illustrated, compressor 2 would be connected to compressor 3 by a suitable conduit and depending on the application of compression system 1 could incorporate interstage cooling. As will be discussed, however, the present invention has equal application to a compression system having a single compressor.
Compressor 2 includes a shroud 10 having an inlet 12 and an impeller 14 that is driven by a motor shaft 16 of the electric motor 4 . The gas is driven by impeller 14 into a volute 18 from which the gas is expelled at a higher pressure than the gas entering compressor 2 from inlet 12 . A back face seal 20 is provided to prevent the escape of high pressure gas from the back face of the impeller 14 . As indicated above, the back face seal 20 is a labyrinth type of seal and circles the back of the impeller 14 . A seal holder 22 retains the impeller back disk seal 20 in place. A cavity 24 is formed behind the impeller 14 that lies between the back disk seal 20 and the motor shaft 16 . A shaft seal 26 that provides a seal about the motor shaft 16 thereby also sealing the cavity 24 . Shaft seal 26 is also held in place by seal holder 22 .
Compressor 3 is provided with a shroud 28 having an inlet 30 that is in flow communication with an outlet (not shown) of the volute 18 of the compressor 2 from which gas is discharged at an intermediate pressure. As indicated above, an interstage cooler could be provided between the outlet of the volute 18 and the inlet 30 . An impeller 32 is driven by the motor shaft 16 of the electric motor 4 at the opposite end thereof to the end at which impeller 14 is driven. The gas is driven by impeller 32 into a volute 34 from the gas is expelled at a higher pressure than the gas entering compressor 3 from inlet 30 . Although not illustrated, a conventional outlet in the volute 34 is provided for discharging the gas at such higher pressure. A back disk seal 36 is provided to prevent the escape of high pressure gas from the back face of the impellar 32 . The back disk seal 36 is supported by a seal holder 38 . A cavity 42 is formed behind the impeller 32 that lies between the back disk seal 36 and the motor shaft 16 . A shaft seal 43 that provides a seal about the motor shaft 16 and therefore also seals cavity 42 . Shaft seal 43 is held in place by a seal holder 38 .
The shroud 10 is connected to the volute 18 which is in turn connected to one end of a cylindrical motor casing 44 . The shroud 28 is connected to the volute 34 which is in turn connected to a motor cap 45 . Motor cap 45 is connected to the opposite end of cylindrical casing 44 . The electric motor 4 has a rotor 46 attached to motor shaft 16 and a stator 48 attached to the inside of cylindrical motor easing 44 . The motor shaft 16 is supported at opposite ends by journal bearings 50 and 52 . Journal bearings 50 and 52 are active magnetic bearings having conductors 54 and 56 attached to the motor shaft 16 and electromagnets 58 and 60 connected to the cylindrical motor casing 44 and the motor cap 45 , respectively. The journal bearings 50 and electromagnetically suspend the motor Shaft 16 for rotational movement. An electromagnetic thrust bearing 62 is also provided. Thrust bearing 62 has a disk-like thrust runner 64 that is a conductor that rotates between inboard and outboard components 66 and 68 , respectively, that are electromagnets that suspend the disk-like thrust runner 64 between the inboard and outboard components. Not illustrated, but as would be well known in the art, gap sensors are provided with associated electronics to differentially power the electromagnets to maintain the gaps between conductors 54 and 56 and the electromagnets 58 and 60 and the disk-like thrust runner 64 between its associated electromagnets of the outboard and inboard components 66 and 68 . The ability to maintain the gaps by active magnetic bearings is not without force limit. This force limit can be exceeded during a surge event. Consequently, as a back up, two sets of bushings 70 and 72 are provided that are connected to the cylindrical motor casing 44 and the motor cap 45 by plates 74 and 76 . During a power loss or upon startup or after a shutdown bushing 70 and 72 will radially support the motor shaft 16 . End elements 78 and 80 connected to motor shaft 16 that are of ring-like configuration to contact the bushings 70 and 72 should the axial force on the motor shaft 16 exceed the capability of the thrust bearing 62 . This can occur during a surge event and such axial forces imparted to motor shaft 16 through bushings 70 and 72 can be particularly severe. As such the number of surge cranes that the motor bushings 70 and 72 can be subjected to will be limited to a small number of events.
During operation of the compression system 1 , the axial forces acting on the motor shaft 16 and therefore, the thrust bearing 62 are imparted as a result of a balance of axial forces on each of the impellers 14 and 32 . With additional reference to FIG. 2 , the impellers are subjected to an inwardly directed eye-side forces, shown as “F 1 ” and “F 2 ”, respectively, that arise as a result of the gas passing through the inlets 12 and 30 . Opposing these forces are back disk forces “F 3 ” and “F 4 ”. These back disk forces arise from the high pressure gas produced by each of the impellers 14 and 32 escaping into the high pressure, outer annular, outer annular regions 82 and 84 that lie between the outer rims 86 and 88 of the impellers 14 and 32 and their associated back disk seals 20 and 36 , respectively. Additionally, the cavities 24 and 42 are also pressurized by low pressure gas through back disk pipes 90 and 92 (shown in FIG. 1 ) and hence forces are exerted in the resulting low pressure, inner annular regions 94 and 96 of the impellers 12 and 32 that lie between the back disk seals 20 and 36 and the motor shaft 16 , respectively. This low pressure gas can be obtained from the inlets 12 and 30 using connections 98 and 100 , respectively. Alternatively, low pressure gas can be obtained from another source such as the inlet to any upstage compressor or in case of air compression, possibly the ambient.
The foregoing can be better understood with reference to FIG. 3 in which the high pressure, outer annular region 82 and the low pressure, inner annular region 94 are shown with respect to the back disk force “F 3 ”. As can be appreciated, the back disk force “F 3 ” is given by the equation:
F 3=π*[( R 0 2 −R 1 2 )* P d +( R 1 2 −R 2 2 )* P c ];
Where the high pressure, outer annular region 82 is the area between R 0 and R 1 , the high pressure gas is P d escaping from the outer rim 86 at R 0 into such region and the low pressure, inner annular region 94 is the annular area between R 1 and R 2 and the low pressure gas in cavity 24 is P c . “F 1 ” is the eye side force equal to the summation of all pressures existing on the impeller eye side and is given by the equation:
F 1 is determined by an integration of the pressure field across the inlet face of the impeller 14 by well known computer modeling techniques that can be carried out with the use of commercially available computer programs such as ANSYS CFX computational fluid dynamics software that can be obtained from Ansys, Inc. of Southpointe, 275 Technology Drive, Canonsburg, Pa. 15317, United States of America.
With reference to FIG. 4 , in the prior art as shown for the normal operation, in the case of impeller 14 , the radii R 1 defining the inner radius of the high pressure, outer annular region 82 (R 0 and R 1 ) and the outer radius of the low pressure, inner annular region 94 (R 1 and R 2 ) is set so that the net impeller thrust during normal operation is set to an acceptably low level or zero. In other words, if zero, F 1 −F 3 =0. The same approach would be used in the case of impeller 32 and consequently, the net impeller thrust during normal operation would also be set to acceptably low level or even zero. In other words, if zero, F 2 −F 4 =0. Since compressor 1 has two impellers 14 and 32 , impeller back disk seals 20 and 36 with desired radii with respect to the impeller or the axis of the motor shaft are set such that the net thrust from both impellers during normal operating conditions is set to an acceptably low level or even zero. In other words, if zero, F 1 −F 3 +F 4 −F 2 =0. In a compressor with a single impeller, the net through for such impeller would be set to zero in the manner indicated above for each of the impellers 14 and 32 .
With continued reference to FIG. 4 , compressors are, however, subject to abnormal operating conditions and the thrust bearing must accommodate these safely. One such abnormal operating condition is surge which produces two alternating, asymmetric forces on the thrust bearing 62 . The first phase (Surge Phase 1) is a sudden loss of discharge pressure arising from aerodynamic instability in the impeller. This results in a decrease in the eye side pressure. However, the back disk force, for instance F 3 for impeller 14 , remains high due to fluidic system inertial effects. This results in a large axial force towards the inlet, for instance inlet 12 with respect to impeller 14 which in such first phase acts in the same direction as force F 3 . The second phase (Surge Phase 2) occurs as the high pressure back disk pressure bleeds off, dramatically reducing the back disc force F 3 , while simultaneously the flow stabilizes and pressure rebuilds in the eye side and increases the eye side force F 1 . This results in a large axial force shown as Surge Phase 2 acting in the direction of F 1 . It is to be noted that during the surge event, both impellers 14 and 32 will be subjected to these oscillating forces because they are interconnected and in fluid communication. Hence, in FIG. 4 the solid lines shown during the surge events represent a summation of the forces acting on the thrust bearing 62 and eventually the bushings 70 and 72 when the forces exceed the thrust bearing capacity of the thrust bearing 62 to resist such forces. In FIG. 4 , the dashed lines represent such thrust bearing capacity (F capacity(+) and F capacity(−) ), beyond which the bushings 70 and 72 will be contacted. The “Positive Overload Margin” and the “Negative Overload Margin” represent differences between such load capacities in positive and negative force directions and the maximum forces generated during the surge event in both positive and negative force directions, namely F Phase 1 and F Phase 2 . The same considerations would apply to a compressor employing a single impeller, but without the summation of forces due to both impellers.
The purpose of the thrust bearing 62 is to prevent these alternating forces from damaging the compressor. When these thrust forces exceed the thrust bearing capacity, F capacity(+) and F capacity(−) of the thrust bearing 62 , the end elements 78 and 80 connected to motor shaft 16 contact the back-up bushings 70 and 72 which are designed to protect the compressor during such event. However, such bushings have a limited life when contacted. As illustrated, the thrust bearings of the prior art can be designed with overload margins, positive and negative, that are designed to adsorb such alternating forces during surge events. However, in the case of oil-free bearings such as magnetic bearings, the load capacities are lower and these overload margins are not high and may not exist. Consequently, as discussed above, such bearings have found limited use. As could be appreciated by those skilled in the art, the same discussion would be equally applicable to air foil bearings which also have limited overload capacities.
It is to be noted that the axial forces during Surge Phase 1 and Surge Phase 2 can be obtained on an operating compression system by direct measurement or from indirect measurements and subsequent calculation, and or can be obtained during the design phase of a compression system from geometry and expected thermodynamic operating conditions. Direct measurement of axial force F phase 1 and F phase 2 on an operating compressor system using magnetic bearings is available by monitoring the magnetic thrust bearing control currents during surge and knowing the force-current coefficient. In-direct measurement and subsequent calculation of F phase 1 and F phase 2 on an operating compressor is performed by measuring thermodynamic conditions within the compression system and using known compressor geometry to compute F phase 1 and F phase 2 axial loading. During the design phase, detailed compressor aerodynamic designs provide expected thermodynamic conditions and actual geometry present that allow calculation of F phase 1 and F phase 2 . The computation of F phase 1 and F phase 2 using geometry and either expected or measured thermodynamic conditions follow the same computational process used by those skilled in the art to calculate the impeller eye side forces F 1 and F 4 and back disk side forces F 2 and F 3 .
In accordance with the present invention, contrary to the prior art, the thrust bearing is preloaded by a force that will increase one of the overload margins at the expense of the other overload margin to in turn increase the ability of the thrust bearing to resist a surge event. With reference to FIG. 5 , as an example, it is assumed that compressors 2 and 3 will experience a system surge such that the F phase 1 will be greater than F phase 2 . In accordance with the present invention, to achieve a greater positive overload margin in Surge Phase 1 of the prior art shown in FIG. 4 , the back disk seal radii for impellers 14 and/or 32 are adjusted to create a non-zero preload thrust value for the normal operation of compressor 1 . As shown in FIG. 5 , a preload force F preload at normal operating conditions will increase the positive overload margin in Surge Phase 1 of the surge event where such increase is required at the expense of decreasing the negative overload margin in Surge Phase 2 of the surge event. As can be appreciated without the preload, the system shown in FIG. 5 would have a dangerously small Positive Overload Margin without the preload force because the force generated in phase 1, F phase 1 would otherwise be closer to the positive thrust bearing capacity F capacity(+) . It is to be noted that had the Negative Overload Margin been less than the Positive Overload Margin, before providing a preload, then the preload force F Preload , would have been exerted in the opposite direction or in other words, toward the positive or F Capacity(+) . In any event, the preload force F preload should be sufficient that both the positive overload margin and the negative overload margin is no less than twenty-five percent of the positive and negative thrust bearing capacities F capacity(+) and F capacity(−) . As can be appreciated, even higher overload margins are desirable and if possible 50 percent and greater. It is to be noted, however, as the overload margins are increased, it is also possible that the thrust bearing capacities must also be increased to accommodate the increased margins. In such case, the entire thrust bearing 62 must be made larger and there exists a limit on the diameter of the thrust runner 64 that will maintain structural integrity at high speeds.
One possible way to produce a preload force in the direction of F 3 during normal operation is by decreasing radii R 1 on impeller 14 , thus, increasing the high pressure outer annular region 82 of the back disk, while decreasing the inner annular low pressure region 94 . The result is to create a larger value of F 3 which acts in the negative direction such that a preload force F preload will now be present in the negative direction at normal operation of the compressor 1 as per shown in FIG. 5 . It is particularly preferred to adjust back seal diameter R 1 to achieve equal positive and negative overload margins if consequence of an overload are the same in either direction.
Although the foregoing preloading has been discussed with respect to manipulating the seal design with the appropriate sizing of R 1 for impellers of either or both compressors 1 and 2 , the preload force can also be adjusted by the pressure acting on the low pressure, inner annular region by the use of a bleed a stream of low pressure gas from an upstream stage and apply it to the low pressure, inner annular region. With reference to FIG. 6 , a multistage compression system l′ is illustrated having a compression system 1 as has been described above and having compressors 2 and 3 . A feed stream 100 is compressed by compressor 2 to produce a compressed stream 102 at an intermediate pressure. Compressed stream 102 is cooled in an intercooler 104 and then further compressed in compressor 3 to produce a compressed stream 106 . Compressed stream 106 is cooled in an intercooler 108 and then introduced into further compressor 5 for further compression. Compressor 5 is driven by an electric motor 6 of similar design to the electric motor 4 described above and such compressor 5 is also provided with seals of the type discussed with respect to compression system 1 and compressors 2 and 3 . The resultant output compressed stream 110 can be cooled by an after-cooler 112 . A bleed stream 114 of low pressure gas for the compression step 5 back disk cavity could be obtained from stream 102 as illustrated or stream 106 . This low pressure bleed stream is fed into a back disk pipe associated with compressor 5 to pressurize its low pressure region behind the impeller to at least assist in the preloading of the compressor 5 in accordance with the present invention. Another benefit of selecting the lowest low pressure stream for the cavity 104 is that the back disk seal radii R 1 can be reduced and consequently less flow of gas will occur across this labyrinth seal. A reduction in seal flow will produce an increase in compression system efficiency. In other words, the smaller the radius of the back disk seal, the less seal area there is for high pressure gas to leak across.
It is to be noted that although the present invention has been discussed with respect to oil-free bearings such as electromagnetic and air foil bearings, the present invention could advantageously be applied to compression systems having conventional bearings lubricated by oil to provide an added margin of safety in case of a surge event. Furthermore, it is not only electrical driven compressors that are subject to surge events, but also, other types of compressors that are driven by other drive mechanisms, for instance, steam or expansion turbines and therefore the present invention in its most broad aspects is not limited to compressors driven by permanent magnet electric motors as illustrated in the Figures and that can be controlled by variable frequency drives. It is also to be noted, that although the present invention has been described with respect to compressors driven at opposite ends of a motor shaft, the present invention would have equal application to a compression system having a single stage of compression.
Additionally, a compression system with a single compressor at one end and an expansion turbine drive or stage at the other end would be a valid application of this invention. This arrangement, known in the industry as a turbocompressor or turbocharger, typically would not include an integral high speed motor. However, it is clear to one skilled in the art that this invention and this turbocompressor or turbocharger embodiment could also include an integral high speed motor, generator, or bidirectional motor/generator.
As will occur to those skilled in the art, although the present invention has been described with reference to preferred embodiments, numerous changes and omissions thereof can be made without departing from the spirit and scope of the present invention as set forth in the appended claims. | The present invention provides a method and apparatus of inhibiting a thrust bearing capacity of a compression system from being exceeded during a surge event in which a thrust bearing is biased with a biasing force to increase the thrust bearing overload margin between the capacity of thrust bearing to absorb axial forces and the greatest force produced during the surge event. This biasing force can be produced by appropriately sizing the high pressure seal on the side of the impeller opposite to the inlet of a compressor of the compression system so that the back disk force produced in the high pressure region of the high pressure seal and the low pressure region located inwardly of the high pressure region creates the desired bias force value and direction. | 5 |
BACKGROUND OF INVENTION
A. Related Applications
There are no applications for patent relating hereto hertofore filed in this or any foreign country.
B. Field of Invention
My invention relates generally to vehicle condition monitoring apparatus and paricularly such apparatus that provides visual indication of engine condition with associated audio and visual alarm means and an engine kill means.
C. Background and Description of the Prior Art
Monitoring apparatus to provide information pertaining to a motor vehicle's various engine and driveline operational characteristics is known in the prior art. Included in this category of apparatus are monitoring devices that provide condition indicators of oil pressure, electrical charging status, water temperature, and even transmission and differential fluid temperature. Such monitoring activity is generally accepted as useful to minimize driveline component damage in motor vehicle operation by alerting an operator to the various conditions of such components during use. Monitoring devices of the past have included various means to alert an operator to unsafe driveline conditions, but driving obligations requiring alertness to highway conditions tend to minimize time available for detailed attention to monitoring devices per se. Accordingly an unsafe condition arising in a motor vehicle driveline may not be detected, and if undetected may result in serious economic loss as well as creating a hazardous driving condition.
Various means have been utilized in prior art devices in an effort to alert an operator to an unsafe vehicle component condition and to this end, devices such as kill switches and illuminated signals have been utilized. Unfortunately, devices of the past have failed to fully address the problem in contemporary driving situations to relay information and alert a driver to necessary monitoring information because of driving obligations, thereby, partially at least, failing to fulfill their intended purposes.
My invention, in an effort to overcome such shortcomings of prior art devices, provides a coordinated warning system having various warning components to alert various of an operator senses to an unsafe condition and thereby providing an operator's necessary time to take adequate steps to deal with driveline problems as may occur. Further included in the monitoring system of the instant invention is an engine kill device that will, after an appropriate time delay, deactivate or shut off a vehicle's engine to minimize damage that might occur due to an engine's continued operation in the presence of an alert condition.
A monitoring console is set forth that may be positioned within a vehicle's dashboard, or as a separate attachable unit securable relative to a dashboard, including engine temperature, oil pressure and charging system indicators. Additional monitoring gauges may be incorporated as desired to provide other information, for example, transmissin fluid temperature and differential fluid temperature. Gauges utilized by my apparatus are formed as a matrix of light emitting diodes (LED) controlled by electronic digital display circuitry which accepts analog information from monitored engine components and converts this information for digital LED display. Typically, a color code system is utilized that varies from green through yellow to red to present indication of condition, be it safe, warning or danger, respectively. This colored graphical display of information is of an easily readable and immediately comprehensible nature to be readily cognizable and interpretable by an operator of a motor vehicle.
Included in the monitoring console is switchable audio means, in the form of a loud speaker, associated with my sensing apparatus that upon occurrence of an unsafe monitored condition emits an audible signal to alert a vehicle operator to the condition. Coordinated therewith is a visual signaler in the form of a flashing illuminated light member, apart from the illuminated LED units, to provide further visual indication of an improper vehicle component condition.
In addition to the above warning elements, the instant invention incorporates an engine kill means, operatively interrelated to the warning annunciators, as a total engine protection package. The engine kill means of my invention operates after an appropriate time delay responsive to an improper operating condition being sensed and indicated. The engine will be shut down to limit damage by its continued operation.
My apparatus thusly provides an interrelated package of a monitoring and display means coordinated with an engine kill device and associated audio and visual warning components. The invention resides not in any one of these structures or features per se, but rather in the synergistic combination of all of them as herein disclosed and claimed to provide the functions that necessarily flow therefrom.
SUMMARY OF THE INVENTION
An automotive component condition monitoring system is provided, including a series of gauges comprised of light emitting diode (LED) display elements to visually indicate status, derived from analog sensors, of various automotive components typically including engine temperature, oil pressure, and electrical charging status. Operatively coordinated therewith is an audio alert speaker that is actuated by an unacceptable monitored condition indicated by the gauge units. The audio component of the monitoring system is switchable to provide selective optional operation. A flashing light indicator, actuable in the same manner as the audio speaker, is provided to further indicate an inappropriate operating condition. An engine kill device operates responsive to alarm annunciation to shut down engine operation after a pre-selected time delay should unacceptable or undesirable conditions persist.
In creating such a device, it is:
A principal object of my invention to provide an automotive component monitoring system to utilize a plurality of visual indicators and associated visual and audio warning devices to alert an operator of an unacceptable operating condition arising from automotive components being monitored.
A further object of my invention to provide such a monitoring apparatus graphically displaying various operating conditions in an automotive environment in a colored graphical fashion for immediate observation and cognition.
Another object of my invention to provide such an automotive component monitoring system that coordinates audible warning signals with and in addition to the graphical displays of component operating conditions.
A further object of my invention to coordinate an engine kill device with the component monitoring means to shut off an engine, after an appropriate time delay, to limit engine damage as a result of a persisting undesirable monitored condition.
A still further object of my invention to provide an automotive monitoring system that is readily mountable and positionable within an automotive operating environment as a part thereof or an addition thereto.
A still further object of my invention to provide such a device that is of new and novel design, of rugged and durable nature, of simple and economical manufacture and one that is otherwise well suited to the uses and purposes for which it is intended.
Other and further objects of my invention will appear from the following specification and accompanying drawings which form a part hereof. In carrying out the objects of my invention, however, it is to be understood that its essential features are susceptible of change in design and structural arrangement with only practical and preferred embodiment being illustrated in the accompanying drawings as is required.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an isometric view of the present invention illustrating its various parts, their configuration, and relationship.
FIG. 2 is an enlarged orthographic view, taken in elevation from the front, of a typical LED display gauge.
FIG. 3 is a block diagram of the essential components of the electrical schematic diagram set forth in FIG. 4.
FIG. 4 is an electrical schematic diagram, in normal symbology, showing the various electrical components of my invention and their operation.
FIG. 5 is an electrical schematic illustration, in normal symbology, showing an optional temperature sensor filter.
DESCRIPTION OF THE PREFERRED EMBODIMENT
My invention comprises generally vehicle instrumentation apparatus 10 providing graphical indication of operating conditions of various monitored automotive components including audio and visual alarms to indicate danger levels occuring in one or more of the various automotive components. An engine kill means is operatively associated with the monitoring apparatus to discontinue engine operation in the presence of a persistent undesirable monitored condition.
My vehicle instrumentation apparatus 10 is formed with a cabinet-like housing including forward face 17 and top 18. Various automotive components monitored are displayed by a matrix-like series of gauges formed of light emitting diode (LED) units. Illustrated in FIG. 1 is a series of LED matrix gauge displays set forth as portions 11, 12 and 13 respectively to graphically illustrate, respectively, charging circuit, engine oil pressure, and engine temperature conditions. While only three matrix displays of LED gauges are illustrated, it is to be understood that the number of such displays utilized is dependent on the number of components to be monitored. Additional gauge displays may be employed to monitor other conditions, transmission temperature and drive gear differential fluid temperature for example. The LED gauge displays are color coded, by appropriate colored diodes or covers, to correlate directly to predetermined parameters of component operating conditions. Colors typically utilized are coventional green indicating a safe operating mode, yellow for a warning condition to indicate possible required attention, and red indicating a danger condition. The details and operation of the circuitry is set forth in further detail hereinafter.
While eight light emitting diodes forming individual indicator elements are illustrated for each matrix defining a gauge, it is to be understood that this number is for illustrative purposes only and a larger or lesser number of such elements may be employed, depending on the degree of gradation desired. The green, yellow, and red scales may be equally divided among the number of elements chosen gradations may be used between these principal colors. It is, however, frequently desirable to utilize an expanded green scale for indication of a broader safe operating range and narrow yellow and red indicating portions to display a narrower danger or alert zone. Furthermore, all LED diode indicator bar displays are designed to overlap in coloration to a predetermined extent to thereby prevent a loss of indication should a particular component reading fall between sections of the discrete LED elements. Accordingly indication of component condition would therefore be visually displayed at all times during the instant invention's use. It is to be understood that the spectrum of colors utilized, green to yellow to red, provides immediate understanding to an observer of component condition without requiring undue concentration or interpretation by the observer.
In electrical communication with the LED display and associated display driver circuitry is an additional visual danger alarm indicator 14. When any of the active gauges 11, 12 or 13 indicate a danger mode by illumination of red by those discrete LED elements, danger alarm indicator 14 will be activated by appropriate circuitry associated with the danger mode indicating LED positions. Alarm indicator 14 defines a somewhat enlarged visual flashing signal to visually alert a user of a danger condition.
Further incorporated in my vehicle instrumentation apparatus 10 is an audio alarm 15 that, in concert with danger visual alarm indicator 14, will provide a noticeable, if not somewhat irritating, accessory alarm arrangement to attract attention to an alert condition. As it is not always desirable and may become unnecessarily distracting to maintain an audio alarm after an operator is alerted, and is taking steps to correct a problem condition, an audio switch 16 is provided on forward face 17 to deactivate audio alarm indicator 15 by manually repositioning switch 16 to an "off" mode. Alternatively, a time delay may be utilized to disengage audio alarm 15.
The LED display gauges include a voltage meter scale 11 to generate a danger or red signal when extreme voltage levels are present in the charging system. The volt meter scale generally ranges from about 11.5 volts to about 16.5 volts to encompass the variance normally encountered in a conventional 12 volt automotive system, but as may be understood, other ranges may be used dependent on the needs or voltage levels of a system in qustion. For example, 6 volt systems are presently utilized in limited numbers of vehicles such as in older or commercial-type vehicles. Furthermore, 24 volt systems may be utilized in certain vehicles. The voltage scale will indicate a red or danger condition at a lower extreme to indicate a lack by charging of an associated charging system and will also generate a danger or red signal at the upper extreme to indicate overcharging. Overcharging tends to ruin a battery in a charging system, whereas undercharging tends to limit the electrical system's effectiveness and either may indicate defects in the system. The yellow portion of the volt meter scale will be lighted, in a 12 volt system, when the charging falls within the 12.0 to 12.6 voltage range, which will denote a general lack of charging in a conventional 12 volt system. The acceptable green area will be lighted in approximately the 13.1 to 16.0 volt range.
Oil pressure indicator 12 is generally a linear pressure indicating gauge ranging from approximately 0 to 55 psi oil pressure levels. Since a problem or red pressure indication level is normally critical only at the lower end of the scale, the gauge will indicate red in a 0 to 10 psi condition will indicate yellow in a 15 to 20 psi condition, and will indicate green at 25 psi and above. These parameters may be modified according to particular need, but will suffice for the majority of contemporary engines.
Engine temperature indicator 13 is of an expanded scale type indicating linearly from approximately 150 degrees F. to 250 degrees F. Green illumination by the LED elements will indicate engine temperatures up to 200 degrees F., with yellow indicating temperatures from approximately 210 to 230 degrees F., and red indicating temperatures above approximately 240 degrees F. where such overheating will indicate a problem condition.
The transmission indicator gauge illustrated schematically in FIGS. 3 and 4, if used, is substantially similar in operation to the engine temperature gauge and would differ only in the temperature ranges monitored.
FIG. 3 sets forth a simplified represenation of the various sensors 19, 54, 68, and 80 presenting analog signals to respective "signal conditioner" circuitry to convert the analog signals to usable form. Respective display drivers 29, 46, 50, and 51 drive the respective LED matrix gauge bar displays. Threshold signal impulses, determined by alert conditions in the various monitored automotive components, activate driver 40 to actuate the various visual and audio alarms 14 and 92 along with selective actuation of engine kill driver 44 optionally actuatable via switch 91.
Attention is directed to FIG. 3 showing a diagrammatic representation of electronic circuitry employed for control and operation of the various gauges utilized. Included therewith is a transmission temperature display gauge; although such a gauge is not shown in FIG. 1, it may be added thereto as desired.
The various gauges of my apparatus operate as follows and as particularly illustrated in FIG. 4.
Voltmeter: The monitored system voltage, which simultaneously provides the operating voltage required by the panel, enters the panel via diode 19, that provides protection against erroneous hookup. A reference voltage source 20 provides input voltage to pin 21 of differential amplifier 22. The monitored system voltage input communicates through divider circuit including resistors 24, 25, and 26 to the other input pin connection 23 of amplifier 22. The output of amplifier 22 is produced as an error voltage at amplifier pin 27, the voltage being proportional to the difference between the input voltages at pins 21 and 23 modified by the ratio of resistors 30 and 28. The output voltage of amplifier 22 is then connected to the input of voltmeter LED driver 29. Driver 29 is formed into an expanded scale meter by connecting the bottom of the driver's reference supply to the junction of voltage divider formed by resistors 31 and 32, as illustrated. Furthermore, since the LED drivers 29, 46, 50 and 51 utilized may be limited to a reference measurement at only one end of the measurement range, and in the voltmeter configuration at a relatively low voltage end, an additional differential amplifier 36 is positioned in the circuit as a voltage comparator. The output of amplifier 36 remains at a relatively "high", or " off" level, unless the monitored system voltage goes higher than the last green LED of driver 29, at pin 27. Above that level, amplifier 36 switches on, lighting the top red LED. Alarm signals are electrically referenced to junction points 38 and 39 when the monitored system voltage attains either high or low voltage preset limits.
Engine kill: Engine kill switch 91 is normally positioned, as illustrated in FIG. 4, to an "on" mode as opposed to optional grounding of the engine kill circuitry to deactivate the engine kill portion of the invention. Whenever amplifier or alarm driver 40 is activated, the alarm signal is relayed from junction 41 via diode 42 and resistor 43 to the differential engine kill driver 44 input at pin 45. Values selected for resistors 43 and 47 and capacitor 48 establish on/off time constants for the engine kill feature which is nominally preset at 30 seconds. The other input to amplifier driver 44 at pin 49, is connected to the output of the reference supply. Amplifier driver 44 is utilized in the circuit as a comparator, and is not normally activated, or alternatively it is of a sufficiently low output, until an alarm signal presented through junction 41 is present long enough to activate it. When amplifier driver 44 does turn on (or to a relatively high output), switch 52 is activated via resistor 53, to in turn activate the engine kill relay. Conventional type contacts such as "C" form contacts, are utilized to handle switching requirements.
Oil pressure meter: Oil pressure sensor 54 provides electrical resistance proportional to monitored oil pressure. The oil pressure sensor is of analog output and connected to a main oil pressure line in a monitored system, such as in an automobile engine. A reference voltage, provided through reference voltage supply 20, is connected through resistor 56 such that resistance related to the aforenoted oil pressure sensor will change with a monitored pressure differential as the voltage at the junction of resistor 56 and the sensor 54 changes. This variable voltage output is connected to differential amplifier 57 at pin 58. The other input at pin 59 is determined by values of a voltage divider including resistances 60 and 61. An output voltage is produced by amplifier 57 at pin 62 which is proportional to the difference between the voltage inputs at pins 58 and 59 proportioned to the ratio of the resistance of resistors 63 and 64. The output voltage, at pin 62 of amplifier 57, is connected to the input of LED oil pressure driver 46. The driver 46 is formed with a fixed value as an upper limit, such as 50 psi for example, to provide acceptable graphic resolution of the LED display matrix at lower oil pressure levels. Alarm signals are generated through points 66 and 67 when oil pressure falls to a preset critical level.
Two variations may occur in use of my invention: firstly, in an application where my invention is the only monitoring system, as might occur when my invention is utilized to replace "idiot" type lights in an OEM system or, secondly, where my invention is utilized as an auxiliary monitoring system working in conjunction with a pre-existing gauge monitor and temperature sensor 68 associated with amplifier 69. The instant invention is compatible in both instances. A further variation exists where an existing engine temperature sensor is powered by the monitored system. In this case, resistor 70 is omitted, resistor 71 is connected to the monitored system voltage, and where the existing gauges have a regulated voltage supplied to them, two Zener diodes are connected across resistor 72 for stability.
An additional variation is required for constructions used by some manufacturers wherein the engine temperature monitoring system utilizes a pulsed voltage supply to drive the system's gauges. This variation may be accommodated by severely dampening the original pulses and thusly avoiding indication of the pulses. However, response times in this type of modified system are extended so that monitoring gauges may not adequately provide needed protection. For these applications, a peak detector and filter arrangement, an example of which is illustrated in FIG. 5, includes a diode 73, resistor 74 and capacitor 75 and field effect switch 76, positioned between the temperature sensor and resistor connection 77 to eliminate the voltage pulses while maintaining a shorter response time than the original system. Alarm signals are derived at points 78 and 79 of the LED display matrix.
Transmission temperature meter: A temperature sensor 80, whose resistance is again proportional to temperature as in the engine temperature sensor, is connected to a transmission output coolant line leading to the transmission radiator or to any source of heated fluid such as in the transmission pan itself. Circuit operation is essentially the same as the oil pressure meter with utilization of differential amplifier 81 and LED driver 51. Alarm signals are derived at points 82 and 83 when the temperature gets too high.
Alarms: Whenever any alarm signals are present at danger signal points 38, 39, 66, 67, 78, 79 and 82, 83, a connection to differential amplifier 40 is generated, which is itself utilized in the circuit as a comparator. A reference level is established at pin 84, one input of amplifier driver 40, by divider resistors 85 and 86. Pin 94, the other input of amplifier driver 40, is biased by resistor 88 such that output of amplifier 40 is not activated, or is of a sufficiently low value, unless an alarm signal is present. When an alarm signal occurs at pin 94, the output of amplifier 40 attains a sufficiently high level such that switch 55 switches on via resistor 90. When switch 55 switches on, visual alarm 14 lights, and if the audio alarm enabling switch 93 is on, the audio alarm 92 is also activated.
The foregoing description of my invention is necessarily of a detailed nature so that a specific embodiment might be set forth as required, but it is to be understood that various modifications of detail, rearrangement and multiplication of parts might be resorted to without departing from its spirit, essence or scope. | A mechanism for monitoring multiple engine and drive-line conditions wherein annunciators are associated with a selectively engageable engine kill means. Illuminated light emitting diode (LED) gauges are arrayed to visually indicate various engine and other driveline conditions. Audio signal generating apparatus is selectively operative by a switching means to provide an audio signal responsive to an alert condition indicated by one or more of the visual display gauges. A flashing light also indicates a danger or alert condition indicated by the LED gauges. Complementing the audio and visual monitoring apparatus is an engine kill device that upon activation and after a preset delay will cut off power to the engine to limit potential engine damage. | 1 |
TECHNICAL FIELD
[0001] The present invention relates to a positioning information forming apparatus, a detection apparatus, and a positioning information forming method.
BACKGROUND ART
[0002] Object positioning detection apparatuses have been proposed, each of which includes a millimeter wave radar and a stereo camera. For example, a first object positioning detection apparatus detects a candidate object to be detected on the basis of camera positioning information calculated based on stereo images taken by a stereo camera. The object positioning detection apparatus then corrects the positioning information on the candidate object to be detected using the radar positioning information provided by the millimeter wave radar. A second object positioning detection apparatus detects the direction of the object to be detected, and then detects the object to be detected using only the direction of the object in the camera positioning information provided by the stereo camera.
[0003] For example, the object detection apparatus disclosed in PTL 1 has a similar scheme to that of the second object positioning detection apparatus mentioned above. Namely, the apparatus detects the direction of the object by the millimeter wave radar and then detects the object using only the camera positioning information overlapping with the detected angular direction.
[0004] In detail, in the traditional object detection method using a millimeter wave radar and a stereo camera, the object is detected by one of the millimeter wave camera and the stereo camera, and then the information provided by the other is supplementarily used.
CITATION LIST
Patent Literature
PTL 1
[0000]
Patent Document 1: Japanese Patent Application Laid-Open No. 2001-296357
SUMMARY OF INVENTION
Technical Problem
[0006] Unfortunately, the traditional object detection method mentioned above is likely to fail to detect the object to be detected if the first detection accuracy is low, despite the use of the supplementary information. For example, the object detection apparatus disclosed in PTL 1 detects the object with the stereo camera only within an area where the millimeter wave radar can detect the object. If the object detection apparatus installed at a road shoulder for detecting vehicles as the object to be detected, is located diagonally behind a vehicle, the power intensity of the millimeter wave which is radiated from the object detection apparatus and reflected by the vehicle sometimes decreases than expected. In such a case, some millimeter wave radars fail to detect the presence of the vehicle, and cannot detect the vehicle even if a supplementary stereo camera is used.
[0007] An object of the present invention is to provide a positioning information forming apparatus, a detection apparatus and a positioning information forming method which have improved object detection accuracy.
Solution to Problem
[0008] An aspect of the present invention provides a positioning information forming apparatus which forms positioning information for a detection apparatus to detect an object on the basis of an image based on information detected by a radar and images taken by a stereo camera, the positioning information forming apparatus including a processing section to process radar distance map information which associates a coordinate group in the image plane of the image based on the information detected by the radar with distance information on each coordinate; a combination section to form combined map information by combining camera distance map information which associates the coordinate group in the image planes of the images taken by the stereo camera with distance information on each coordinate and the processed radar distance map information; and a coordinate transforming section disposed on the input stage of the processing section to transform a coordinate system of the radar distance map information input to the processing section to a reference coordinate system.
[0009] Another aspect of the present invention provides a positioning information forming apparatus which forms positioning information for a detection apparatus to detect an object on the basis of an image based on information detected by a radar and images taken by a stereo camera, the positioning information forming apparatus including, a processing section to process radar distance map information which associates a coordinate group in the image plane of the image based on the information detected by the radar with distance information on each coordinate; a combination section to form combined map information by combining camera map information which associates a coordinate group in an image planes taken by the stereo cameras with distance information on each coordinate and the processed radar distance map information, and a coordinate transforming section disposed on the output stage of the processing section and on the input stage of the combination section transforms a coordinate system of radar distance map information input in the processing section to a reference coordinate system.
[0010] An aspect of the present invention provides a positioning information forming method for forming positioning information for a detection apparatus to detect an object on the basis of an image based on information detected by a radar and images taken by a stereo camera, the positioning information forming method including processing radar distance map information which associates a coordinate group in an image plane of the image based on information detected by the radar with distance information on each coordinate; transforming a coordinate system of the radar distance map information to a reference coordinate system; and forming combined map information by combining camera distance map information which associates a group of coordinates in image planes of images taken by the stereo camera with distance information on each coordinate and the processed radar distance map information.
Advantageous Effects of Invention
[0011] The present invention provides a positioning information forming apparatus, a detection apparatus and a positioning information forming method which have improved object detection accuracy.
BRIEF DESCRIPTION OF DRAWINGS
[0012] FIG. 1 is a block diagram illustrating the main configuration of a positioning information forming apparatus in accordance with Embodiment 1 of the present invention;
[0013] FIG. 2 is a block diagram illustrating the configuration of a detection apparatus in accordance with Embodiment 1 of the present invention;
[0014] FIG. 3 illustrates stereo images;
[0015] FIG. 4 illustrates exemplary camera distance map information;
[0016] FIG. 5 illustrates exemplary radar distance map information;
[0017] FIG. 6 illustrates the configuration of a detection apparatus in accordance with Embodiment 2 of the present invention;
[0018] FIG. 7 illustrates an image plane coordinate system (U′, V′) of a virtual position of the detection apparatus installed on the road surface;
[0019] FIG. 8 is a block diagram illustrating a configuration of an information processing section;
[0020] FIG. 9 is a block diagram illustrating a configuration of an information processing section;
[0021] FIG. 10 is an illustration of a coordinate transforming process;
[0022] FIG. 11 is an illustration of a coordinate transforming process;
[0023] FIG. 12 is an illustration of a smoothing process;
[0024] FIG. 13 is an illustration of a level adjusting process;
[0025] FIG. 14 is a block diagram illustrating the configuration of a detection apparatus in accordance with Embodiment 3 of the present invention;
[0026] FIG. 15 is a table illustrating information processes for subregions of the objects;
[0027] FIG. 16 is a schematic view illustrating a smoothing process for a vehicle subregion in camera distance map information;
[0028] FIG. 17 is an illustration of reflection intensity characteristics obtained when the objects to be detected are a sideways vehicle and a pedestrian;
[0029] FIG. 18 is an illustration of changes in brightness characteristics on a vehicle image; and
[0030] FIG. 19 is an illustration of vehicle and pedestrian areas.
DESCRIPTION OF EMBODIMENTS
[0031] Embodiments of the present invention will now be described in detail with reference to accompanying drawings. In the following description, the same components are given the same number without duplicated description.
Embodiment 1
[0032] (Main Configuration of Positioning Information Forming Apparatus)
[0033] FIG. 1 illustrates the main configuration of positioning information forming apparatus 100 in accordance with Embodiment 1 of the present invention. Positioning information forming apparatus 100 receives “first distance map information” obtained by a first positioning system and “second distance map information” obtained by a second positioning system as input values. “Distance map information” is information associating a coordinate group in an image plane with “distance information” on each coordinate. The first positioning system in this embodiment includes a stereo camera. The first distance map information, therefore, is camera distance map information calculated based on stereo images taken by the stereo camera. “Distance information” in camera distance map information is, for example, a parallax value or a distance value. The second positioning, system includes a millimeter wave radar. The second distance map information, therefore, is radar distance map information calculated based on information detected by the millimeter wave radar. “Distance information” in radar distance map information is, for example, a distance value or reflection intensity.
[0034] In FIG. 1 , positioning information forming apparatus 100 includes coordinate transforming section 101 , information processing section 102 , and a combination section 103 .
[0035] Coordinate transforming section 101 conforms the coordinate system of radar distance map information to the “reference coordinate system” by coordinate transformation of radar distance map information. The “reference coordinate system” is used as a reference for combining distance map information input from a plurality of positioning systems in combination section 103 which will be described below. In Embodiment 1, the “reference coordinate system” is a coordinate system of camera distance map information.
[0036] Information processing section 102 smoothes radar distance map information. The smoothing leads to a moderate change in “distance information” among the radar distance map information.
[0037] Combination section 103 combines camera distance map information and the processed radar distance map information to generate “combined map information.”
[0038] (Configuration of Detection Apparatus 200 )
[0039] FIG. 2 illustrates a configuration of a detection apparatus 200 in accordance with Embodiment 1 of the present invention. Detection apparatus 200 includes positioning information forming apparatus 100 . In FIG. 2 , Detection apparatus 200 includes coordinate transforming section 101 , information processing section 102 , combination section 103 , stereo camera 201 , millimeter wave radar 202 , distance map information calculating section 203 and 204 , and detection section 205 . Stereo camera 201 and distance map information calculating section 203 configure a first positioning system, while millimeter wave radar 202 and distance map information calculating section 204 configure a second positioning system.
[0040] Stereo camera 201 includes a plurality of cameras and outputs camera images (namely, stereo images) taken by these cameras to distance map information calculating section 203 .
[0041] For example, stereo camera 201 consists of two cameras which are disposed in parallel at a distance of 20 cm. FIG. 3 illustrates images of a vehicle at a distance of 20 m from these cameras, the images being taken by these cameras. FIG. 3A illustrates an image taken by the camera on the left in the direction of shooting (namely, a left camera image), and FIG. 3B illustrates an image taken by the camera on the right in the direction of shooting (namely, a right camera image).
[0042] Distance map information calculating section 203 calculates camera distance map information on the basis of a stereo image output from stereo camera 201 . Specifically, distance map information calculating section 203 calculates the separation distance between the object and the stereo camera 201 on the basis of the difference in the positions (namely, a parallax) of the same object which appears on the left and right camera images. Distance map information calculating section 203 calculates camera distance map information through calculation of the separation distances of all pixels making up the left and right camera images.
[0043] The separation distance between the object and the stereo camera 201 can be calculated from, for example, Equation 1:
[0000]
(
Equation
1
)
Z
=
B
f
P
x
d
[
1
]
[0044] wherein, Z represents the distance [m] between the stereo camera and the object. B represents the camera distance [m], f represents the camera focal point distance [m], Px represents the length per one pixel [m/pixel] in a horizontal axis direction of the image and d represents the parallax [pixel].
[0045] More specifically, the parallax can be calculated, for example, in the following way. One of the left and right images is defined as a target image and the other as a reference image. A partial image (namely, a partial target image) having a predetermined size (for example, 4×4 pixels) is selected from the target image. A search range having a predetermined size (for example, about several tens of pixels) is selected from the reference image. Partial reference images having the same size as the partial target image are then selected in sequence by shifting the position of the partial reference image, and a partial reference image corresponding to the partial target image is identified by calculating the evaluation function on the basis of a brightness value of the partial target image and each partial reference image. The difference between the partial target image and the identified partial reference image corresponds to a parallax. Since the parallax is calculated in this way, a small change in brightness between the partial target image and the partial reference image would cause an unsatisfactory parallax. This indicates if a shooting surface of an object, for example, has few patterns, like a roof of a vehicle or a road surface, a parallax is barely obtained.
[0046] FIG. 4 illustrates exemplary camera distance map information. The camera distance map information in FIG. 4 is obtained from the right and left camera images illustrated in FIG. 3 . In FIG. 4 , the parallax value is used as “distance information.” The magnitude of the parallax is represented by the shade and the area where a parallax cannot be obtained is described in white due to a zero parallax value. Symbols U and V shown in FIG. 4 represent image plane coordinates which are differentiated from the real space coordinates (X, Y, Z). Each coordinate in the image plane coordinate system corresponds to a pixel where the lateral direction of the image is defined as U coordinates and the longitudinal direction as V coordinates.
[0047] Back to FIG. 2 , millimeter wave radar 202 radiates millimeter waves and detects the reflected millimeter waves. Millimeter wave radar 202 , then, outputs the results of detection to distance map information calculating section 204 .
[0048] Millimeter wave radar 202 is, for example, of a FMCW scheme which includes an antenna capable of outputting waves having a narrow beam width. Millimeter wave radar 202 receives the reflected waves by mechanically rotating the antenna. Incidentally, the FMCW scheme can acquire the distance and direction from millimeter wave radar 202 to an object, the travelling speed of an object, and reflection intensity from the object.
[0049] Direction map information calculating section 204 calculates radar distance map information on the basis of the results of detection received from millimeter wave radar 702 .
[0050] FIG. 5 illustrates exemplary radar distance map information. In FIG. 5 , a distance value is used as “distance information”. The magnitude of the distance is represented by the shade. In FIG. 5 , the image plane coordinate system has the azimuth direction of millimeter wave radar 202 and the depression angle orthogonal to the azimuth direction.
[0051] Back to FIG. 2 , coordinate transforming section 101 transforms the coordinates of radar distance map information so that the camera distance map information and the radar distance map information have the same coordinate system.
[0052] Information processing section 102 smoothes the radar distance map information.
[0053] Combination section 103 generates “combined map information” by combining the camera distance map information and the processed radar distance map information.
[0054] Detection section 205 detects an object taken by stereo camera 201 on the basis of the “combined map information.”
[0055] (Operation of Detection Apparatus 200 )
[0056] The operation of detection apparatus 200 having the above-mentioned configuration will now be explained with particular emphasis on a coordinate transforming process, an information process, a distance map information combination process, and a detection process.
[0057] (Coordinate Transforming Process)
[0058] Coordinate transforming section 101 transforms the coordinates of the radar distance map information so that the camera distance map information and the radar distance map information have the same coordinate system. Specifically, coordinate transforming section 101 transforms the coordinates such that the radar distance map information represented by the coordinate system having orthogonal axes of the azimuth direction and the depression angle of millimeter wave radar 202 is represented by an image plane coordinate system (U, V). The coordinate is transformed using, for example. Equation 2.
[0000]
(
Equation
2
)
(
u
v
)
=
f
(
tan
θ
tan
ϕ
)
[
2
]
[0059] wherein, f represents the focal distance of the stereo camera, and θ and φ represents the azimuth angle and the depression angle, respectively, of the millimeter wave radar.
[0060] (Information Processes)
[0061] Information processing section 102 smoothes the radar distance map information. Specifically, information processing section 102 smoothes at least one of the azimuth angle and the depression angle of the radar distance map information. The smoothing leads to a moderate change in reflection intensity of the azimuth angle or the depression angle. Information processing section 102 smoothes the radar distance map information after the coordinate transformation in coordinate transforming section 101 .
[0062] The smoothing is performed using, for example, a smoothing filter represented by Equation 3, resulting in smoothing the distances of all the coordinates included in the radar distance map information.
[0000]
(
Equation
3
)
[
1
/
16
2
/
16
1
/
16
2
/
16
4
/
16
2
/
16
1
/
16
2
/
16
1
/
16
]
[
3
]
[0063] A millimeter wave radar generally has the following positioning characteristics: the distance to the object can be measured with high accuracy compared with the positioning information of a stereo camera while the boundary of the object in the azimuth angle and the depression angle cannot be readily determined due to a technical challenge to narrow the width of the antenna beam. The above-mentioned smoothing of the radar distance map information eliminates information corresponding to negative characteristics, leading to obtaining radar distance map information rich in information corresponding to positive characteristics.
[0064] (Combination Process of Distance Map Information)
[0065] Combination section 103 transforms the “distance information” (namely, distance value or reflection intensity) associated with each coordinate in the processed radar distance map information so that this distant information coincides with the “distance information” (namely, a parallax value or a distance value) associated with each coordinate in the camera distance map information. For example, if each coordinate is associated with a parallax value in the camera distance map information, combination section 103 transforms the “distance information” (namely, a distance value or reflection intensity) to a parallax value. In other words, combination section 103 optionally conforms the type of “distance information” between the radar distance map information and the camera distance map information.
[0066] Combination section 103 combines the camera distance map information and the radar distance map information by calculating the geometric means of the “distance information” of the corresponding coordinate between the radar distance map information and the camera distance map information, thereby generating the “combined map information.”
[0067] (Object Detection Process)
[0068] Detection section 205 detects the object taken by stereo camera 201 based on the “combined map information.” For example, if the “combined map information” is generated by a parallax distribution in image plane coordinates (U, V), the coordinates having a parallax similar to that of distribution as an object can be detected from the parallax distribution that has undergone coordinate transformation such that the V axis of the “combined map information” is vertical to the ground based on the installation conditions of the stereo camera (for example, installation height and angle). Explanation on conventional methods for detecting an object from the parallax distribution is omitted. The results of the detection may be superimposed on the right image (or the left image) to be output to a display (not illustrated) or to controllers such as a traffic signal controller for public use.
[0069] In Embodiment 1, combination section 103 in positioning information forming apparatus 100 combines the camera distance map information and the radar distance map information to generate “combined map information.” The combined map information is used during an object detection process in detection apparatus 200 .
[0070] Based on the combined information of the camera distance map information and the radar distance map information, an object can be detected at improved accuracy. More specifically, the elimination of unwanted noise reflection from the ground or walls can be expected, which allows setting a lower object detection threshold. Thus, it is possible to detect an object conventionally judged as being not detectable.
[0071] Combination section 103 combines the camera distance map information and the radar distance map information by calculating the geometric means of the “distance information” of the corresponding coordinate between the radar distance map information and the camera distance map information.
[0072] This combination facilitates the recognition of the boundary of an object due to values remaining only in coordinates yielding parallax in the camera distance map information.
[0073] The coordinate transformation of radar map information is performed prior to the information processes. Alternatively, the coordinate transformation may be performed after the information processes and prior to a combination process. Consequently, coordinate transforming section 101 may be disposed on the output stage of information processing section 102 and the input stage of combination section 103 .
Embodiment 2
[0074] (Configuration of Detection Apparatus 300 )
[0075] FIG. 6 illustrates the configuration of detection apparatus 300 in accordance with Embodiment 2 of the present invention. Detection apparatus 300 includes positioning information forming apparatus 400 .
[0076] In FIG. 6 , positioning information forming apparatus 400 includes coordinate transforming section 401 and 402 , information processing section 403 and 404 , and combination section 405 .
[0077] Coordinate transforming section 401 transforms the coordinates of the camera distance map information to conforms the coordinate system of the camera distance map information to the “reference coordinate system”. The “reference coordinate system” used in coordinate transforming section 401 is defined by the parallax and the coordinate axis U′ of the image plane coordinate system (U′, V′) of a virtual position of detection apparatus 300 installed on the road surface. FIG. 7 illustrates the image plane coordinate system (U′, V′) of a virtual position of detection apparatus 300 installed on the road surface.
[0078] More specifically, coordinate transforming section 401 transforms the coordinates of the camera distance map information through two steps. Details will be described later.
[0079] Coordinate transforming section 402 transforms the coordinates of the radar distance map information to conform the coordinate system of the radar distance map information to a “reference coordinate system”. The “reference coordinate system” used in coordinate transforming section 402 is also defined by the parallax and the coordinate axis U′ of the image plane coordinate system (U′, V′) of a virtual position of detection apparatus 300 installed on the road surface.
[0080] More specifically, coordinate transforming section 402 transforms the coordinates of the radar distance map information through two steps. Details will be described later.
[0081] Information processing section 403 performs the smoothing, level adjustment, and normalization of the camera distance map information after the coordinate transformation in coordinate transforming section 401 .
[0082] FIG. 8 illustrates information processing section 403 including smoothing section 411 , level adjusting section 412 , and normalization section 413 .
[0083] Smoothing section 411 smoothes the camera distance map information after the coordinate transformation in coordinate transforming section 401 . Smoothing section 411 performs smoothing only in the parallax-axis direction. Smoothing section 411 applies a smoothing filter to the parallax-axis direction in any U′ coordinate and smoothes the camera distance map information by the sequential shift of the U′ coordinate.
[0084] Level adjusting section 412 adjusts the level of the camera distance map information by applying a level adjusting filter to the smoothed camera distance map information.
[0085] Normalization section 413 normalizes individual level values associated with the (U′, parallax) coordinate group included in the level-adjusted camera distance map information using the maximum value among these level values.
[0086] Information processing section 404 performs the smoothing, level adjustment, and normalization of the radar distance map information after the coordinate transformation in coordinate transforming section 401 .
[0087] FIG. 9 illustrates information processing section 404 including smoothing section 421 , level adjusting section 422 , and normalization section 423 .
[0088] Smoothing section 421 smoothes the radar distance map information after the coordinate transformation in coordinate transforming section 402 . Smoothing section 421 performs smoothing only in the U′-axis direction. Smoothing section 421 applies a smoothing filter to the U′-axis direction in any parallax coordinate and smoothes the radar distance map information by the sequential shift of the parallax coordinate.
[0089] Level adjusting section 422 adjusts the level of radar distance map information by applying a level adjusting filter to the smoothed radar distance map information.
[0090] Normalization section 423 normalizes individual level values associated with the (U′, parallax) coordinate group included in the level-adjusted camera distance map information using the maximum value among these level values.
[0091] Combination section 405 combines the processed camera distance map information and processed radar distance map information to generate “combined map information.”
[0092] (Operation of Detection Apparatus 300 )
[0093] The operation of detection apparatus 300 having the above-mentioned configuration will be explained with particular emphasis on the operation of positioning information forming apparatus 400 .
[0094] (Coordinate Transforming Process 1)
[0095] Coordinate transforming section 401 transforms the coordinates of the camera distance map information to conform the coordinate system of the camera distance map information to a “reference coordinate system”. The “reference coordinate system” used in coordinate transforming section 401 is defined by the parallax and the coordinate axis U′ of the image plane coordinate system (U′, V′) of a virtual position of detection apparatus 300 installed on the road surface.
[0096] More specifically, coordinate transforming section 401 transforms the coordinates of camera distance map information through the following two steps.
[0097] (1) Coordinate transforming section 401 projects the camera distance map information in the image plane coordinates (U, V) (see FIG. 10A ), onto image plane coordinates (U′, V′), to perform the coordinate transformation, where the camera distance map information is obtained using images taken from the installation position of detection apparatus 300 .
[0098] In detail, the vector at a coordinate point before coordinate transformation û=(u, v, 1, d) and the vector at a coordinate point after the coordinate transformation û ′=(u′, v′, 1, d′) leads to the relation û ′=S −1 DSû, where D represents the transformation matrix including installation parameters of a stereo camera (installation height, rotation angle) and S represents the matrix of camera correction parameters (for example, camera distance, rotation angle).
[0099] (2) Coordinate transforming section 401 calculates the parallax histogram within a range of the V′ coordinate in the V′ direction at each U′ coordinate on the basis of the camera distance map information of an image plane coordinate system (U″, V′). Coordinate transforming section 401 calculates the parallax histogram by limiting the range of the V′ coordinate to parts corresponding images above the road surface. The camera distance map information is thereby transformed into the “reference coordinate system.” FIG. 10B illustrates exemplary camera distance map information after the coordinate transformation into the “reference coordinate system”.
[0100] Using the parallax d (u′, v′) in the (u′, v′) coordinates and the series N (u′, d) in the (u′, d) coordinates, the transformation from d(u′, v′) to N (u′, d) is represented by the following equation:
[0000] for( i= 0 ;i<n;i ++){for( j= 0 ;j<m;j ++){ N ( i,d ( i,j ))++;}}
[0101] where, n and m represent the ranges of the U′ coordinates and the V′ coordinates, respectively.
[0102] (Coordinate Transforming Process 2)
[0103] Coordinate transforming section 402 transforms the coordinates of the radar distance map information to conform the coordinate system of radar distance map information to the “reference coordinate system”, The “reference coordinate system” used in coordinate transforming section 402 is also defined by the parallax and the coordinate axis U′ of the image plane coordinate system (U′, V′) of a virtual position of detection apparatus 300 installed on the road surface.
[0104] More specifically, coordinate transforming section 402 transforms the coordinates of radar distance map information through the following two steps.
[0105] (1) Coordinate transforming section 402 projects the radar distance map information onto a plane (including an installation plane of detection apparatus 300 ) parallel to the installation plane of detection apparatus 300 , to perform the coordinate transformation, where the radar distance map information associates each direction (namely, a direction defined by a pair of the azimuth angle and the depression angle) with the “distance information” of each direction FIG. 11A illustrates exemplary radar distance map information after the coordinate transformation.
[0106] (2) Coordinate transforming 402 calculates the reflection intensity distribution in each U′ and the parallax coordinates on the basis of the radar distance map information projected onto a plane parallel to the installation plane of detection apparatus 300 . The radar distance map information is thereby transformed into the “reference coordinate system.” FIG. 11B illustrates exemplary radar distance map information after the coordinate transformation.
[0107] Supposing that the installation position and angle of stereo camera 201 conforms to those of millimeter wave radar 202 , coordinate transforming section 402 calculates the reflection density distribution by the following equation using the camera correction parameter series S.
[0000]
p̂′=S
−1
p̂
[0108] wherein, the vector p̂=(x, 0, z, 1) represents the coordinates (x, z) of a plane parallel to the installation plane of detection apparatus 300 , and the vector p̂ ′=(u′, 0, 1, d) represents the coordinates (u′, d) in a plane defined by U′ and the parallax.
[0109] (Information Processes 1)
[0110] Information processing section 403 performs the smoothing, level adjustment, and normalization of the camera distance map information after the coordinate transformation in coordinate transforming section 401 .
[0111] (Smoothing)
[0112] Smoothing section 411 smoothes the camera distance map information after the coordinate transformation in coordinate transforming section 401 . Smoothing section 411 performs smoothing only in the parallax-axis direction. Smoothing section 411 , as illustrated in FIG. 12A , smoothes the entire camera distance map information by applying a smoothing filter to the parallax-axis direction in any U′ coordinate, and then sequential shifting of the filter to the next U′ coordinate. FIG. 12B illustrates an exemplary smoothing filter used.
[0113] Consequently, smoothing only in the parallax-axis direction can reduce negative characteristics of the camera distance map information (namely, less accurate distance information than that of the radar distance map information), while enhances positive characteristics (namely, better recognition of the boundary of an object in the azimuth direction than that of the radar distance map information).
[0114] Specifically, as is illustrated in FIG. 12A , multiplying a smoothing filter 501 having a given length of the filter by the parallax value data sequence in each U′ coordinate leads to a moderate change in series of the parallax-axis direction in the camera distance map information.
[0115] Smoothing filter 501 used is the Hanning function, which is represented by the following equation:
[0000]
(
Equation
4
)
g
c
(
x
)
=
0.5
+
0.5
cos
2
π
λ
c
×
(
-
λ
c
2
≤
x
≤
λ
c
2
)
g
c
(
x
)
=
0
(
x
<
-
λ
c
2
,
λ
c
2
<
x
)
[
4
]
[0116] where λ c represents the length of the filter.
[0117] FIG. 12B illustrates the shape of Equation 4.
[0118] Equation 5 holds provided that coordinate values are N (u′, d) and N′ (u′, d) before and after, respectively, the smoothing.
[0000]
(
Equation
5
)
N
(
u
′
,
d
)
=
∑
x
g
c
(
x
-
d
)
·
N
(
u
′
,
x
)
[
5
]
[0119] (Level Adjustment)
[0120] Level adjusting section 412 multiplies the smoothed camera distance map information by a level adjusting filter to adjust the levels of the camera distance map information. The level adjusting filter used is characterized by the increase of the coordinate values with the decrease of the parallax. Specifically, as is illustrated in FIG. 13A , the level adjusting filter has a shape indicating a monotonous decrease of the level values (namely, weight) with the increase of the parallax.
[0121] The purpose of the level adjustment is to adjust the levels of the series corresponding to the parallaxes of the individual portions of the same object, because the series corresponding to the parallaxes of portions far from stereo camera 201 is smaller than that of closer portions.
[0122] As is illustrated in FIG. 13A , the level adjusting filter used in level adjusting section 412 and the level adjusting filter used in level adjusting section 422 have different shapes. Also in the radar distance map information, the reflection intensity corresponding to the parallaxes of portions far from millimeter wave radar 202 is smaller than that of closer portions of the same object. The camera distance map information and the radar distance map information however have different reduction rates; hence, level adjustments of the camera distance map information and the radar distance map information using respective level adjusting filters with different shapes can adjust the relative level between the camera distance map information and the radar distance map information.
[0123] (Normalization)
[0124] Normalization section 413 performs normalization by dividing the individual level values associated with the (U′, parallax) ordinate group included in the level-adjusted camera distance map information by the maximum value among these level values.
[0125] (Information Processes 2)
[0126] Information processing section 404 performs the smoothing, level adjustment, and normalization of the radar distance map information after the coordinate transformation in coordinate transforming section 402 .
[0127] (Smoothing)
[0128] Smoothing section 421 smoothes the radar distance map information after the coordinate transformation in coordinate transforming section 402 . Smoothing section 421 performs smoothing only in the U′-axis direction. Smoothing section 421 , as illustrated in FIG. 12C , smoothes the entire radar distance map information by applying a smoothing filter to the U′-axis direction in any parallax coordinate, and then sequential shifting of the filter to the next parallax coordinate. FIG. 12D illustrates an exemplary smoothing filter used.
[0129] Consequently, smoothing only in the U′-axis direction can reduce negative characteristics of the radar distance map information (namely, less accurate recognition of the boundary of an object in the azimuth direction than that of the camera distance map information), while enhancing positive characteristics (namely, more accurate distance information than that of the camera distance map information).
[0130] Specifically, as is illustrated in FIG. 12C , multiplying a smoothing filter 502 having a given length of the filter by the U′ data sequence in each parallax coordinate leads to a moderate change in reflection intensity of the U′-axis direction in the radar distance map information.
[0131] Exemplary smoothing filter 502 used is the Hanning function, which is represented by the following equation:
[0000]
(
Equation
6
)
g
r
(
x
)
=
0.5
+
0.5
cos
2
π
λ
r
×
(
-
λ
r
2
≤
x
≤
λ
r
2
)
g
r
(
x
)
=
0
(
x
<
-
λ
r
2
,
λ
r
2
<
x
)
[
6
]
[0000] where λr represents the length of the filter.
[0132] FIG. 12D illustrates the shape of Equation 6.
[0133] Equation 7 holds provided that coordinate values are P (u′, d) and P′ (u′, d) before and after, respectively, the smoothing.
[0000]
(
Equation
7
)
P
(
u
′
,
d
)
=
∑
x
g
r
(
x
-
u
′
)
·
N
(
x
,
d
)
[
7
]
[0134] (Level Adjustment)
[0135] Level adjusting section 422 applies a level adjusting filter to the smoothed radar distance map information to adjust the levels of the radar distance map information. Level adjusting section 422 , as illustrated in FIG. 13B , multiplies level adjusting filter 601 by the radar distance map information while the multiplied level adjusting filter 601 is sequentially shifted in the U′-axis direction, thereby adjusting the level of the entire radar distance map information. The level adjusting filter used is characterized by the increase of the coordinate values with the decrease of the parallax. Specifically, as is illustrated in FIG. 13A , the level adjusting filter has a shape indicating a monotonous decrease of the level values (namely, weight) with the increase of the parallax.
[0136] The purpose of the level adjustment is to adjust the levels of the reflection intensity corresponding to the parallaxes of the individual portions of the same object, because the reflection intensity corresponding to the parallaxes of portions far from millimeter wave radar 202 is smaller than that of closer portions.
[0137] (Normalization)
[0138] Normalization section 423 performs normalization by dividing the individual level values associated with the (U′, parallax) coordinate group included in the radar-adjusted camera distance map information by the maximum value among these level values.
[0139] (Combination Process)
[0140] Combination section 405 combines the processed camera distance map information and the processed radar distance map information to generate “combined map information.” Specifically, combination section 405 generates “combined map information” by multiplying the values of the processed camera distance map information by the corresponding values of the processed radar distance map information, a pair of the values being associated with an identical coordinate.
[0141] In Embodiment 2, in positioning information forming apparatus 400 , coordinate transforming section 401 transforms the coordinates of the camera distance map information to conform the coordinate system of the camera distance map information to a “reference coordinate system”. Coordinate transforming section 402 transforms the coordinates of the radar distance map information to conform the coordinate system of radar distance map information to the “reference coordinate system”. The “reference coordinate system” is defined by the parallax and the coordinate axis U′ of the image plane coordinate system (U′, V′) of a virtual position of detection apparatus 300 installed on the road surface.
[0142] Information processing section 403 smoothes the camera distance map information after the coordinate transformation in coordinate transforming section 401 only in the parallax-axis direction. Information processing section 404 smoothes the radar distance map information after the coordinate transformation in coordinate transforming section 402 only in the U′-axis direction. Combination section 405 combines the processed camera distance map information and processed radar distance map information to generate “combined map information.”
[0143] Such a process allows smoothing only in the parallax-axis direction to reduce negative characteristics of the camera distance map information (namely, less accurate distance information than that of the radar distance map information) and to enhance positive characteristics (namely, better recognition of the boundary of an object in the azimuth direction than that of the radar distance map information). Furthermore, the process allows smoothing only in the U′-axis direction to reduce negative characteristics of the radar distance map information (namely, less accurate recognition of the boundary of an object in the azimuth direction than that of the camera distance map information) and to enhance positive characteristics (namely, more accurate distance information than that of the camera distance map information). The accuracy of the object detection can be improved by combined information having enhanced positive characteristics of both camera distance and radar distance map information.
Embodiment 3
[0144] In Embodiment 2, information processing section 403 smoothes the entire region defined by parallax values and U′ included in the camera distance map information. Information processing section 404 smoothes the entire region defined by parallax values and U′ included in the radar distance map information. In Embodiment 3, the region defined by U′ and parallax values is divided into subregions on the basis of the type of an object having a high frequency of appearance, and the length of the smoothing filter is adjusted for each subregion.
[0145] (Configuration of Detection Apparatus 700 )
[0146] FIG. 14 illustrates the configuration of detection apparatus 700 in accordance with Embodiment 3 of the present invention. Detection apparatus 700 in FIG. 14 includes positioning information forming apparatus 800 .
[0147] In FIG. 14 , positioning information forming apparatus 800 includes information processing section 801 and 802 , and memory 803 .
[0148] Memory 803 holds area designation information. The term “area designation information” indicates the subregions (occasionally, referred to as “subregions of the objects”), into which the region defined by the parallax values and U included in the camera distance and the radar distance map information are divided on the basis of the type of the object having a high frequency of appearance. If detection apparatus 700 is installed at a place such as a pedestrian crossing or a traffic intersection, the area designation information includes a subregion where vehicles are mainly detected (occasionally, referred to as “a vehicle subregion”) and a subregion where pedestrians are mainly detected (occasionally, referred to as “a pedestrian subregion”).
[0149] Information processing section 801 has the same function as information processing section 403 . Information processing section 801 , however, adjusts the length of the smoothing filter for individual subregions of the objects indicated by the area designation information held in memory 803 . Specifically, information processing section 801 adjusts the length of the smoothing filter to the average size of the vehicle shot in the vehicle subregion, and to the average size of the pedestrian in the pedestrian subregion. In other words, the length of the filter used in a vehicle subregion is larger than that in a pedestrian subregion.
[0150] Alternatively, information processing section 801 may adjust the weight of the filter for individual subregions of the object.
[0151] Information processing section 802 has the same function as information processing section 404 . Information processing section 802 , however, adjusts the length of the smoothing filter for individual subregions of the object indicated by the area designation information held in memory 803 . Specifically, information processing section 802 adjusts the length of the smoothing filter to the average size of the vehicle shot in the vehicle subregion and to the average size of the pedestrian in the pedestrian subregion. In other words, the length of the filter used in a vehicle subregion is larger than that in a pedestrian subregion.
[0152] Alternatively, information processing section 802 may adjust the weight of the filter for individual subregions of the object.
[0153] (Operation of Detection Apparatus 700 )
[0154] The operation of detection apparatus 700 having the above-mentioned configuration will now be explained with particular emphasis on the information processes in positioning information forming apparatus 800 . FIG. 15 is a table illustrating information processes for subregions of the objects and FIG. 16 is a schematic view illustrating a smoothing process for a vehicle subregion in camera distance map information.
[0155] (Information Processes 1)
[0156] Information processing section 801 performs the smoothing, level adjustment, and normalization of the camera distance map information after the coordinate transformation in coordinate transforming section 401 . The level adjustment and normalization are the same as that in Embodiment 2, and explanations thereof are omitted.
[0157] (Smoothing)
[0158] Information processing section 801 smoothes the camera distance map information after the coordinate transformation in coordinate transforming section 401 . Information processing section 801 performs the smoothing only in the parallax-axis direction. Information processing section 801 adjusts the length λc of the smoothing filter to the average size of the vehicle shot in the vehicle subregion, and to the average size of the pedestrian in the pedestrian subregion. In other words, as illustrated in FIG. 15 , information processing section 802 adjusts the length λc of the filter to long one in a vehicle subregion (in FIG. 15 , subregion (B)) and short one in a pedestrian subregion (in FIG. 15 , subregion (A)).
[0159] Information processing section 801 , as illustrated in FIG. 15 , uses the weight of the filter in a vehicle subregion (in FIG. 15 , subregion (B)), but does not use the weight of the filter in a pedestrian subregion (in FIG. 15 , subregion (A)). Specifically, information processing section 801 adjusts the weight of the filter such that, as illustrated in FIG. 16 , the maximum weight is attained in the center of the region and the weight monotonously decreases toward the boundaries in a vehicle subregion.
[0160] (Information processes 2)
[0161] Information processing section 802 performs the smoothing, level adjustment, and normalization of the radar distance map information after the coordinate transformation in coordinate transforming section 402 . The level adjustment and normalization are the same in Embodiment 2, and explanations thereof are omitted.
[0162] (Smoothing)
[0163] Information processing section 802 smoothes the radar distance map information after the coordinate transformation in coordinate transforming section 402 . Information processing section 802 performs the smoothing only in the U′-axis direction. Information processing section 802 adjusts the length λr of the smoothing filter to the average size of the vehicle shot in the vehicle subregion, and to the average size of the pedestrian in the pedestrian subregion. In other words, as illustrated in FIG. 15 , information processing section 802 adjusts the length λr of the filter to long one in a vehicle subregion (in FIG. 15 , subregion (B)) and short one in a pedestrian subregion (in FIG. 15 , subregion (A)).
[0164] Information processing section 801 , as illustrated in FIG. 15 , uses the weight of the filter in a pedestrian subregion (in FIG. 15 , subregion (A)), but does not use the weight of the filter in a vehicle subregion (in FIG. 15 , subregion (B)). The weight of the filter used is increased by a conventional equation.
[0165] The objects to be detected have different between reflection intensity characteristics and parallax characteristics depending on the types thereof. FIG. 17 is an illustration of reflection intensity characteristics on objects of interest which are a sideways vehicle and a pedestrian. FIG. 17A illustrates an image of a sideways vehicle, while FIG. 17B illustrates an image of a pedestrian. FIG. 17C illustrates the reflection intensity of the objects in FIGS. 17A and 17B . In FIG. 17C , Peak P 1001 is the peak of the reflection intensity of the vehicle, while Peak P 1002 is the peak of the reflection intensity of the pedestrian. As seen in FIG. 17C , Peak P 1002 is significantly smaller than Peak P 1001 . This indicates that the reflection cross-sectional area of the pedestrian is smaller than that of the vehicle due to the uneven surface of the pedestrian.
[0166] In camera distance map information, unlike the reflection intensity characteristics, there is no large difference between a vehicle and a pedestrian. FIG. 18 , however, demonstrates that satisfactory parallax cannot be obtained from the image of the central portion of the sideways vehicle due to small changes in brightness (see, Peak P 1003 ).
[0167] The frequencies of appearance of the vehicle and the pedestrian differ according to area. As illustrated in FIG. 19 , detection apparatus 700 installed at the traffic intersection can barely detects pedestrians in the central area of the traffic intersection, but detects on the pedestrian crossing and sidewalks. Consequently, the traffic crossing area, as illustrated in FIG. 19 , can be classified into a vehicle subregion (in FIG. 19 , subregion (B)) and a pedestrian subregion (in FIG. 19 , subregion (A)).
[0168] Object detection accuracy depends on the degree of matching between the object to be detected and the length of the smoothing filter.
[0169] In this embodiment, information processing sections 801 and 802 adjust the length and weight of the smoothing filter for individual subregions of the objects indicated by the area designation information held by memory 803 . This operation can reduce the probability of erroneous detection of an object. In particular, the adjustment of the length of the filter can reduce erroneous detection of a plurality of pedestrians as a single pedestrian or a single vehicle as a plurality of vehicles. In addition, the smoothing using the weight of the filter illustrated in FIG. 16 can reduce erroneous detection of a single vehicle as a plurality of vehicles.
[0170] Area designation information may be generated by an operator of detection apparatus 700 in a way that pedestrian subregions and vehicle subregions are selected using a detection apparatus 700 -installation map appearing on an display apparatus (not illustrated). Alternatively, the area designation information may be calculated based on the map information including the area information and on the information about the locations of installation of detection apparatus 700 .
Other Embodiments
[0171] (1) In each of the embodiments described above, the millimeter wave radar includes an antenna having a narrow-width beam in a direction parallel to the road surface. The reflected waves are detected with the antenna mechanically rotating parallel to the road surface. The antenna may have a narrow beam width in the direction perpendicular to the road surface. In such a case, the antenna is mechanically moved parallel and perpendicularly to the road surface to acquire the same radar distance map information as in the embodiments described above, attaining the object of the present invention. This technique can also be applied to a radar having an antenna with a narrower beam width, such as a laser radar, than that of a millimeter wave radar.
[0172] (2) Unlike the embodiments described above, software associated with the hardware can also be used to attain the object of the present invention, instead of sole use of the hardware.
[0173] Each functional block in the embodiment described above is typically integrated in the form of LSI. Individual functional blocks may be independently integrated into single chips, or a part or all the functional blocks may be integrated into a single chip. LSI may be referred to as IC, system LSI, super LSI, or ultra LSI according to the degree of integration.
[0174] Any other approach for integration of the circuits, such as a dedicated circuit or a general purpose processor, can also be employed instead of the LSI. Other methods may also be used, such as FPGA (field programmable gate array) which can be programmed after the production of LSI or a reconfigurable processor in which the connection or arrangement of circuit cells in the LSI can be reconfigured.
[0175] The functional blocks will be integrated by a new technology substituting for LSI as a result of the progress in semiconductor technology or derivative technology in the field of integrated circuit configuration. Application of biotechnology is a possible alternative.
[0176] The entire disclosure of the specifications, drawings and abstracts in Japanese Patent Application No 2011-013174 filed on Jan. 25, 2011 is incorporated herein by reference.
INDUSTRIAL APPLICABILITY
[0177] A positioning information forming apparatus, a detection apparatus, and a positioning information forming method in accordance with the present invention are useful for improving object detection accuracy.
REFERENCE SIGNS LIST
[0000]
100 , 400 , 800 Positioning information forming apparatus
101 , 401 , 402 Coordinate transforming section
102 , 403 , 404 , 801 , 802 Information processing section
103 , 405 Combination section
200 , 300 , 700 Detection apparatus
201 Stereo camera
202 Millimeter wave radar
201 , 204 Distance map information calculating section
205 Detection section
411 , 421 Smoothing section
412 , 422 Level adjusting section
413 , 423 Normalization section
803 Memory | Provided is a positioning information forming device which improves object detection accuracy. This device comprises a synthesis unit ( 103 ) which synthesizes camera distance map information and radar distance map information and generates “synthesized map information”. This synthesized map information is used for object detection processing by a detection device ( 200 ). In this way it is possible to improve object detection accuracy by being able to detect objects based on information in which the camera distance map information and radar distance map information have been synthesized. In other words, by synthesizing the camera distance map information and radar distance map information, it is possible to remove unnecessary noise due to reflection from the ground and walls, etc. and therefore set object detection thresholds to low values. It is therefore possible to detect even objects the detection of which was judged to be impossible in the past. | 6 |
PRIORITY CLAIM
This invention claims priority to U.S. provisional application Ser. No. 60/370,085, filed Apr. 4, 2002.
FIELD OF THE INVENTION
This invention relates generally to ocean powered desalinization systems.
BACKGROUND OF THE INVENTION
It has long been recognized that the oceans provide tremendous potential in kinetic energy which can be harvested to generate electricity. Across the globe there are many tidal electric generation systems installed and in full operation. An example of an installed and fully operational tidal electro-generation system is the barrage system installed near St. Malo on the Brittany Coast in France across the La Rance estuary. The St. Malo system is a 240 megawatt system and has been reliably generating electricity for a good number of years. Despite this good record the complete blockage of the La Rance estuary has caused significant environmental effects. The submerged turbine blades have interfered with migration of fish and the overall barrage itself has blocked shipping. Other tidal powered systems include tidal fences and submerged underwater windmills and all have a greater or lesser effect on the environment. The aforementioned power generating systems, though effective, are big and require a complex series of power grids to convey the power off the barrage or tidal fence to an offshore power collection and distribution system.
Smaller tidal and wave powered electro-generation systems include various wave riding devices which bob up and down and move dynamos that generate electricity. Although these systems are smaller and can be located at remote locations, they nevertheless require electricity to be harvested and a grid to be constructed onto these bobbing devices. The grid in particular is cumbersome and has limited their practical implementation.
Various locations across the globe in which tidal ranges are ideal for generating electricity are places that also happen to be devoid of water. Such locations are in Africa, the Mideast and Polynesia. As these desert coastal regions are commonly devoid of electricity and drinkable water, various devices have been proposed to meet both the electricity and potable water demands of coastal residents. Such a system is described in U.S. Pat. No. 5,167,786 which generates compressed oxygen and hydrogen gas on a toroidal float which moves up and down with the waves and the tide. This up and down motion drives a DC generator which in turn is arranged to electrolytically produce hydrogen and oxygen gas. The hydrogen and oxygen gas is stored on the toroidal float apparatus and transferred to a reaction chamber to chemically generate electricity. Electricity thus generated is then sent to a DC motor to drive a high pressure pump which forces sea water through a reverse osmosis membrane to remove salt and produce drinkable fresh water. This toroidal gas generation system to generate electricity to drive electric DC motors in order to make drinkable water is a desalinization system which works but it is unnecessarily complex. Where there is a need primarily for fresh water to be generated from a desalinization process especially in remote regions a gas generated gas reactor system is unduly complex and likely to not have the robustness to serve in remote locations. Furthermore, such a system is very costly.
In many desolate parts of the world that have a good tidal and wave coastline but yet is primarily in an arid region there is a need to have a robust mechanically simple desalinization system powered by the tides and wave action of the seas. Such a system is simplified if it does not have electric generators but instead goes directly to the desalinization process. Such a simplified system uses the potential and kinetic energy of the oceans to directly send saltwater into a desalinization system without the intervening production of electricity inherent in other systems.
The need for a simplified robust desalinization system powered directly by the oceans to make fresh water and store the fresh water is needed. Such a system must be fairly mobile, assembleable, disassembleable, and transportable to remote coastal locations where potable water is not easily obtained.
SUMMARY OF THE INVENTION
The instant invention overcomes many of the disadvantages of having a dual electricity generation system and a saltwater desalinization system. A preferred embodiment of the present invention utilizes a barge mounted to a plurality of pistons that reciprocate inside a matching plurality of vessels or cylinders, and utilizes the vertical motion being caused by the action of tidal forces and waves. Each piston is in fluid communication with the ocean as the source of power to perform on board desalinization. The barge is restricted to up and down vertical motions via a plurality of posts or piles secured by embedded positioning into the bedrock of the sea floor to stabilize the barge against ocean-caused lateral displacement. The up and down motion of waves and tidal forces causes the pistons to reciprocate upwards and downwards with its waves and tides. That is, as the tide rises or falls, the pistons rise and fall, generating a two-way pumping action. This pumping action is due to the combined forces of rising tides and falling tides, or the combined forces of rising waves and falling waves. There is no intervening electric generation of power from the use of alternate powered devices. This reciprocating pumping action delivers a pressurized saltwater flow. Using a plumbing and valving system, the pressurized saltwater flow is directed to an on board desalinization system, such as a reverse osmosis (RO) filtration system, that generates and stores fresh water into reservoirs by being powered directly from the reciprocating movement of waves and tides. The on board desalinization system is in fluid communication with each cylinder and reservoir.
Another preferred embodiment of the present invention does not utilize bedrock embedded piles or posts to keep the barge positioned at a chosen site on the ocean floor, but instead secures the barge's ocean floor location through supports massive enough to resist lateral displacement caused by wave and tidal action. This alternate preferred embodiment is particularly suited for ocean floors having deep sandy beds.
Yet another preferred embodiment of the present invention uses a single pile or post floating barge or platform that slidably oscillates between vertical limits imposed by wave and tidal action. The single pile is secured to the ocean floor by a support massive enough to resist lateral displacement of ocean flows. The pile or post projects through a platform aperture. Alternatively, the single pile may be embedded in the ocean floor to increase stability against lateral displacement.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.
FIG. 1 is a preferred general arrangement of an approximately 50 foot by 100 foot barge which contains the desalinization system. The cylinders are depicted below the water line, and barge positions depicted include a high tide position and a low tide position;
FIG. 2 is an up view or plan view of the preferred deck arrangement of the barge;
FIG. 3 is a cutaway view detailing a cutaway view of a preferred reverse osmosis filtration system and storage reservoir arrangement in the approximately 50 foot by 100 foot barge;
FIG. 4 is a depiction of the preferred machinery arrangement in a cutaway view of the approximately 50 by 100 foot barge;
FIG. 5 is a depiction of a preferred arrangement of the cylinder and in-flowing and out-flowing check valves;
FIG. 6 is a schematic of the reverse osmosis purification system and its piping connection with cylinders and storage reservoirs; and
FIG. 7 is a schematic depiction of a preferred embodiment of the invention with the cylinders located above the water line.
DETAILED DESCRIPTION OF THE INVENTION
Arrangement of the barge mounted tidal powered desalinization system comprises a series of pistons mounted to the barge which oscillate within cylinders attached to a shaft which is mounted into the bedrock of the ocean bed. To the shaft are attached a plurality of cylinders where each cylinder has a piston and the piston has a rod which is attached to the barge bottom. As the barge moves up or down with tidal or wave action the pistons move up or down within the cylinders. Through appropriate plumbing valves to direct the flow of saltwater in a one-way direction results in the delivery of saltwater into the reverse osmosis membranes.
The design of the instant invention using the rising and falling of the tides to create a flow of seawater under pressure suitable for feeding existing reverse osmosis desalinization systems. The design consists of a floating vessel attached to one end of a standard type hydraulic cylinder, the other end of the cylinder is connected to the sea floor. As the floating vessel or barge rises and falls with the tides, the cylinder is extended and compressed. This motion pumps the seawater. The pressure and flow rate of seawater depends on cylinder size and the mass of the vessel and the displacement of the vessel which occurs during tidal cycles.
On the upward stroke of the cycle the buoyant force of the float limits the amount of pressure that can be created. On the downward stroke the weight of the float determines the maximum pressure. The actual work on the down stroke is a function of gravity, not of the tides. The cylinders are sized so that the float is not really floating but is suspended on the cylinders.
In concert with the up and down motion of the barge in response to tidal flows and wave action, the cylinders are configured to cyclically deliver pressurized saltwater for subsequent desalinization. Simultaneously, the pressurized and delivered saltwater is replaced with incoming charges of salt water that will be subsequently pressurized and delivered for desalinization with the next tidal or wave action. For example, as the tide recedes the buoyant force on the barge decreases and the barge falls, pushing each piston downward into their respective cylinders. During each piston's downward stroke, each cylinder is configured to deliver pressurized saltwater for desalinization, and concurrently, to fill each cylinder with a replacement charge of saltwater. Similarly, as the tide comes in, the buoyant force on the barge increases and the rising barge pulls each piston upward into their respective cylinders. During the piston upward stroke, each cylinder is configured to deliver pressurized saltwater for desalinization, and concurrently, to fill each cylinder with a replacement charge of saltwater.
Thus, an unbalanced hydraulic cylinder is used as the pumping mechanism. The down stroke acts on the larger surface area of the cylinder. This is done so that the substantial mass of the floating vessel can be used to create pressure and flow. On the upstroke, buoyant forces lift the floating vessel, thereby acting on the smaller surface area portion of the hydraulic cylinder, generating a forward flow of saltwater. As the tide recedes, the floating vessel sinks, generating a down stroke. The down stroke generates a reverse flow of saltwater. The result is a system that is half powered by tidal forces and half powered by gravity. Pumping action can also be used to pump the fresh water exiting the reverse osmosis filters into the water distribution system resulting in the conversion of saltwater into potable water under pressure without any electrical or fuel input.
The invention is best described by referring to the figures. In FIG. 1 the invention 10 is shown in two positions depending upon the tide position. A barge 12 is located in a high tide position and a low tide position. The Barge 12 moves up and down about along a first post 14 and along with a second post 34 . Attached to the top side of the barge 12 is a first platform 15 which circumscribes the first post 14 and a second platform 42 which circumscribes the second post 34 . The first post 14 and the second post 34 are mounted into the bedrock of the ocean floor. The first post 14 is supported by a first post guide 30 and the second post 34 is supported by a second post guide 36 . The first and second guides 30 and 36 sit atop the bedrock of the ocean floor. On the first guide 30 is seen a first plurality of cylinders that includes a first cylinder 20 and a second cylinder 32 . On second guide 36 is seen a second plurality of cylinders that includes a first cylinder 38 and a second cylinder 40 . Within each cylinder is a piston seal and a piston rod assembly. Referring to the first cylinder 20 as representative for other cylinders, the other cylinders including, but not limited by, the second cylinder 32 of the first plurality of cylinders and the second cylinders 39 and 40 of the second plurality of cylinders, the piston rod assembly includes a piston seal 22 which is attached to a piston rod 18 . The piston rod 18 is mounted to the first platform 15 by a rod end 16 . Likewise, other piston rods are attached to the other seals within the other cylinders and are similarly attached to the first platform 15 and the second platform 42 . As can be seen in FIG. 1 there are two extreme positions to the barge 12 when it floats at high tide and when the barge 12 floats at low tide. Similarly, the pistons will also occupy two extreme locations, the high tide position and the low tide position, and reciprocate within their respective cylinders. As depicted in FIG. 1 , the piston seal 22 occupies the top position of the first cylinder 20 when the barge 12 is at high tide, then transits down the first cylinder 20 to the low tide position. As the tides and the waves oscillate in their own diurnal cycle, the piston seal 22 migrates between the high tide extreme and the low tide extreme. In so doing, saltwater is pumped by the movement of the barge as a consequence of rising with the tide and falling with gravity, generating a pressurized saltwater flow powered by a suction cycle and a discharge cycle. Using a plumbing and valving system (not shown), the suction and discharge cycles of the double acting cylinders are regulated to produce a steady pressurized flow of saltwater. The plumbing and valving systems include a first plumbing and valving system configured to deliver pressurized water to the on board desalinization system and a second plumbing and valving system configured to deliver incoming saltwater to the cylinders concomitantly as the pressurized saltwater is delivered from the cylinders.
FIG. 2 shows in more detail the deck arrangement of the barge 12 in a top view. The top of the barge 12 is shown the first post 14 and the second post 34 . The first post 14 is surrounded by the first platform 15 and the second post 34 is shown surrounded by the second platform 42 . Beneath the first platform 15 is the first plurality of cylinders. The first plurality of cylinders includes the first cylinder 20 , the second cylinder 32 , a third cylinder 60 , and a fourth cylinder 62 . Beneath the second platform 42 resides the second plurality of cylinders. The second plurality of cylinder includes the first cylinder 38 , the second cylinder 40 , a third cylinder 64 , and a fourth cylinder 66 .
FIG. 3 shows a cutaway view of a preferred reverse osmosis filtration system and storage reservoir arrangement in the approximately 50 foot by 100 foot barge. The cutaway view is from the top view of the barge 12 . The cutaway view 104 shows four compartments. The four compartments include a first compartment 110 , a second compartment 120 , a third compartment 130 and a fourth compartment 140 . Each compartment contains a stack of reverse osmosis membranes and a plurality of water storage reservoirs. The first compartment 110 shows a first reverse osmosis stack 112 which is fed by a first plurality of pre-filtration tanks. The first plurality of pre-filtration tanks include a first tank 114 , a second tank 116 , and a third tank 118 . The second compartment 120 has a second reverse osmosis stack 122 which is fed by a second plurality of pre-filtration tanks. The second plurality of pre-filtration tanks includes a first tank 124 , a second tank 126 , and a third tank 128 . The third compartment 130 has a third reverse osmosis membrane stack 132 which is fed by a third plurality of pre-filtration tanks. The third plurality of pre-filtration tanks include a first tank 134 , a second tank 136 , and a third tank 138 . The fourth compartment 140 contains a fourth reverse osmosis stack 142 which is fed by a fourth plurality of pre-filtration tanks. The fourth plurality of pre-filtration tanks includes a first tank 144 , a second tank 146 , and a third tank 148 . Each reverse osmosis stack uses a third plumbing and valving system (not shown) to deliver the generated fresh water to the plurality of water storage reservoirs. Also seen in the cutaway view 104 is a first moon pool 150 delineating the space for the first post 14 and a second moon pool 160 delineating the space for the second post 34 . Each reverse osmosis stack can be loaded with RO membranes configured to meet varying levels of salinity and silt contents in the saltwater.
FIG. 4 is a side cutaway view of the barge 12 . The first and second platforms 15 and 42 are shown above the first compartment 110 and the second compartment 120 respectively. Within the first compartment 110 is seen the first reverse osmosis stack 112 and the second pre-filtration tanks 116 and 118 of the first plurality of pre-filtration tanks. Similarly, inside the second compartment 120 is seen the second reverse osmosis stack 122 and the first and second pre-filtration tanks 124 and 126 of the second plurality of prefiltration tanks.
FIG. 5 is a depiction of a preferred arrangement of the cylinder and in-flowing and out-flowing check valves. FIG. 5 shows the arrangement for the cylinder 20 but is also representative for cylinders 32 , 38 , and 40 of FIG. 1 . Inside the cylinder 20 is a connecting rod seal 204 that makes and maintains sealing contact with the connecting rod 18 . As the connecting rod 18 reciprocates within the cylinder 20 , the piston 22 creates a vacuum on the trailing side of the piston 22 , and simultaneously creates pressure on the leading side of the piston 22 . The vacuum created on the trailing side of piston 22 pumps in saltwater through incoming check valves 208 A or 212 A, depending if the piston 22 is moving downwards, or upwards, respectively. Similarly, the pressure created on the leading side of the piston 22 pressurizes the salt water and delivers to the outgoing check valves 208 B and 212 B, depending if the piston 22 is moving upwards or downwards, respectively.
FIG. 6 is a schematic of the reverse osmosis purification system its piping connection with cylinders and storage reservoirs. Again, using the cylinder 20 as representative for cylinders 32 , 38 , and 40 of FIG. 1 , ambient pressure saltwater is drawn in through incoming check valve 208 A through a first pipe 216 . Alternatively, ambient pressure saltwater is drawn in through incoming check valve 212 A trough a second pipe 220 . Depending on the position of the connecting rod 18 and the piston 22 , pressurized saltwater is delivered to the outgoing check valves 208 B and 212 B. Pressurized saltwater from outgoing check valve 208 B is delivered by a third pipe 224 to a reverse osmosis filtration system 234 . Similarly, pressurized saltwater from outgoing check valve 212 B is delivered by a fourth pipe 228 to the reverse osmosis filtration system 234 . The reverse osmosis filtration system 234 includes the reverse osmosis stacks 112 , 122 , 132 , and 142 working in concert to produce purified water from saltwater. Saltwater excess not purified by the RO system 234 is discarded through a fifth pipe 238 . Freshwater generated by the RO system 234 is delivered through a sixth pipe 244 to a plurality of storage reservoirs 248 . The plurality of storage reservoirs 248 is representative of the reservoirs 114 , 116 , 118 , 124 , 126 , 128 , 134 , 136 , 138 , 144 , 146 , and 148 .
FIG. 7 is a schematic depiction of a preferred embodiment of the invention with the cylinders not immersed in the saltwater, but instead located above the water line and located onboard the barge. A portion of the barge 12 illustrating the post 14 is shown in FIG. 7 . The first pipe 216 and the second pipe 220 extend below the water line and each connects with the cylinder 20 that is now located onboard the barge 12 , above the water line. Incoming saltwater is delivered via the first pipe 216 and the second pipe 220 . Pressurized saltwater is delivered to the RO system 234 (not shown) from the cylinder 20 via the third pipe 224 and the fourth pipe 228 .
While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. For example, more than two piles or posts can be used as vertical guides to the barge. More than four piston and cylinder assemblies may be mounted around each pile or post, and may be located in different sections of the barge. The vessels or cylinders may be constructed of metal, corrosion resistant metals, plastics, or plastic-lined metals of sufficient thickness and corrosion resistance to permit pumping action. For the preferred alternate embodiment not utilizing bedrock-embedded piles or posts to stabilize against ocean motion caused lateral displacement of the barge, the pile guides are configured to receive cement or receive heavy object attachments to impart enough weight and mass to resist and stabilize the barge against lateral displacement from ocean motion forces. All embodiments of the present invention may also be used to purify polluted fresh water sources. Piles or posts may be connected to the barge internally through barge apertures or secured along the periphery of the barge with collars. Cylinders may be placed around the piles or internally spaced above or below throughout the cross-sectional area of the barge platform. The invention may be adapted to existing floating structures, such as airport runways and parking lots. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. | A tidal-powered desalinization system is mounted on a barge that oscillates about fixed pier structures, generating a two-way pumping action. The two-way pumping action is changed to a single direction flow of seawater. The sea water is directed into an on-board desalinization system. Fresh water is produced and collected in reservoirs, without an intervening generation of electricity. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. application Ser. No. 12/728,874, filed Mar. 22, 2010, which is a continuation-in-part of U.S. application Ser. No. 11/503,837 filed Aug. 14, 2006 (now U.S. Pat. No. 7,700,238) which claims priority from Korean Patent Application No. 10-2005-0074697, filed Aug. 16, 2005, all of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a non-aqueous electrolyte-based, high-power lithium secondary battery having a long-term service life and superior safety at both room temperature and high temperature, even after repeated high-current charge and discharge.
BACKGROUND OF THE INVENTION
Technological development and increased demand for mobile equipment have led to a rapid increase in the demand for secondary batteries as an energy source. In recent years, applicability of secondary batteries has been realized as power sources for electric vehicles (EVs) and hybrid electric vehicles (HEVs). In the light of such trends, a great deal of research and study has been focused on secondary batteries which are capable of meeting various demands. Among other things, there has been an increased demand for lithium secondary batteries having high-energy density, high-discharge voltage and power output stability.
Particularly, lithium secondary batteries for use in EVs require not only high-energy density and capability to exert large power output within a short period of time, but also a long-term service life of more than 10 years even under severe conditions in which high-current charge/discharge cycles are repeated within a short time, thus necessitating remarkably superior safety and long-term service life compared to conventional small-size lithium secondary batteries.
Lithium ion secondary batteries that have been used in conventional small-size batteries generally employ a layered structure of lithium cobalt composite oxide as a cathode material and a graphite-based material as an anode material. However, the main constitutional element of the lithium cobalt composite oxide, cobalt, is very expensive and is not suitable for use in electric vehicles due to safety concerns. Therefore, as the cathode material of lithium ion batteries for EVs, a lithium manganese composite oxide having a spinel structure made up of manganese is ideal in terms of both cost and safety.
However, the lithium manganese composite oxide, upon high-temperature and high-current charge/discharge, undergoes elution of manganese ions into an electrolyte due to the influence of the electrolyte, thus resulting in degradation of battery properties and performance. Thus, there is a need for measures to prevent such problems. In addition, the lithium manganese composite oxide has drawbacks such as a low capacity per unit weight, i.e., a low charge density, as compared to conventional lithium cobalt composite oxides or lithium nickel composite oxides. Thus, there is a limit to charge density of the battery and in order to enter practical use as the power source of EVs, HEVs and the like, designs of the battery to solve such disadvantages should be effected together.
In order to alleviate the above-mentioned respective disadvantages, various studies and attempts to fabricate electrodes using a mixed cathode active material have been made. For example, Japanese Patent Laid-open Publication Nos. 2002-110253 and 2004-134245 disclose techniques utilizing a mixture of lithium/manganese composite oxide, and lithium/nickel/cobalt/manganese composite oxide and/or lithium/nickel/cobalt/manganese composite oxide to enhance recovery output and the like. These arts, however, still suffer from problems associated with a poor cycle life of the lithium manganese oxide and limited improvement of safety.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to solve the above problems, and other technical problems that have yet to be resolved.
Specifically, an object of the present invention is to provide a cathode active material for a secondary battery, comprising a mixture of a manganese spinel oxide having a substitution of a manganese (Mn) site with a certain metal element and a lithium/nickel/cobalt/manganese composite oxide, whereby the battery can secure safety and, due to alleviation of disadvantages of the lithium/manganese oxide, can have a long-term service life at both room temperature and high temperature, even after repeated high-current charge and discharge.
Another object of the present invention is to provide a lithium secondary battery comprising the above-mentioned cathode active material, upon fabrication of the cathode.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a cathode active material for a lithium secondary battery, comprising a mixture of a lithium/manganese spinel oxide represented by Formula I below and a lithium/nickel/cobalt/manganese composite oxide represented by Formula II below:
Li 1+x Mn 2−y M y O 4 Formula I
wherein,
M is a metal having an oxidation number of 2 to 3; 0≦x≦0.2; and 0≦y≦0.2.
Li 1+z Ni b Mn c Co 1−(b+c) O 2 Formula II
wherein,
−0.1≦z≦0.1; 0.2≦b≦0.7; 0.1≦c≦0.6; and b+c<1, wherein the mixing ratio of the lithium/manganese spinel oxide: lithium/nickel/cobalt/manganese composite oxide is in the range of 10:90 to 90:10 (w/w); and wherein the cathode active material exhibits the life characteristics that the capacity at 300 cycles is more than 75% relative to the initial capacity.
In accordance with another aspect of the present invention, there is provided a lithium secondary battery comprising the above-mentioned cathode active material-containing cathode, an anode, a separator and a non-aqueous electrolyte.
Hereinafter, the present invention will be described in more detail.
As discussed hereinbefore, the present invention is characterized by using a mixture of the lithium/nickel/cobalt/manganese oxide and the lithium/manganese spinel oxide wherein a portion of manganese (Mn) is substituted with other metal elements, as a cathode active material.
In the lithium/manganese spinel oxide of Formula I, manganese (Mn) is substituted with a metal (M) having an oxidation number of 2 or 3 within the predetermined range. Herein, the metal (M) may be preferably aluminum (Al), magnesium (Mg) or both of them.
Since the oxidation number of the substituent metal is smaller than that of manganese (Mn), an increasing amount of the substituted metal leads to a decrease in an average value of the oxidation number and a relative increase in the oxidation number of manganese (Mn), consequently resulting in inhibition of manganese (Mn) dissolution. That is, life characteristics are further improved as the amount of the substituted metal (y) in the lithium/manganese spinel oxide increases. However, since an increasing amount of the substituted metal (y) is also accompanied by a decrease of initial capacity, a maximum value of y is preferably less than 0.2, which is capable of maximizing improvements of the life characteristics and minimizing reduction of the initial capacity of the battery. More preferably, the value of y is in the range of 0.01 to 0.2.
Where appropriate, high-temperature cycle characteristics and capacity preservation characteristics may be improved to some extent by adjusting the composition ratio of constituent elements in the lithium/manganese spinel oxide, but there are limitations to high-temperature safety and capacity per weight.
Therefore, as the cathode active material, the present invention uses the lithium/manganese spinel oxide in admixture with a certain lithium/nickel/cobalt/manganese composite oxide of Formula II which is an active material expected to increase a service life due to a higher stability thereof.
The lithium/nickel/cobalt/manganese composite oxide is a lithium oxide which simultaneously contains nickel, manganese and cobalt elements, as shown in Formula II, and significantly improves, in combination with the lithium/manganese spinel oxide, the safety and life characteristics of the cathode active material according to the present invention. The lithium/nickel/cobalt/manganese composite oxide contains at least 0.2 M nickel, provided that it contains manganese and cobalt. Particularly, the lithium/nickel/cobalt/manganese composite oxide having a relatively high content of nickel compared to that of manganese and cobalt is more preferred for realization of high capacity.
In one preferred embodiment, the lithium/nickel/cobalt/manganese composite oxide has an element composition represented by Formula IIa, characterized in that lithium ions intercalate into and deintercalate from mixed transition metal oxide layers (“MO layers”) and some of MO layer-derived Ni ions are inserted into intercalation/deintercalation layers of lithium ions (“lithium layers”) to thereby interconnect the MO layers:
Li 1+z Ni b Mn c Co 1−(b+c) O 2 Formula IIa
wherein, −0.1≦z≦0.1, 0.4≦b≦0.7, 0.1≦c≦0.5, and 0.6≦b+c≦0.9.
The inventors of the present invention have confirmed that the crystal structure stabilizes contrary to conventionally known or accepted ideas in the related art that intercalation/deintercalation of lithium ions will be hindered when some of nickel ions go down to and immobilize in the lithium layers, so it is possible to prevent problems associated with collapse of the crystal structure caused by the intercalation/deintercalation of lithium ions. As a result, since the lifespan characteristics and safety are simultaneously improved due to no occurrence of additional structural collapse by oxygen desorption and prevention of further formation of Ni 2+ , the battery capacity and cycle characteristics can be significantly improved and a desired level of rate characteristics can be exerted.
That is, due to the insertion of some Ni ions into the lithium layers, the lithium/nickel/cobalt/manganese composite oxide of Formula Ha does not undergo disintegration of the crystal structure with maintenance of the oxidation number of Ni ions inserted into the lithium layers, thereby being capable of maintaining a well-layered structure, even when lithium ions are released during a charge process. Hence, a battery comprising the lithium/nickel/cobalt/manganese composite oxide of Formula Ha having such a structure as a cathode active material can exert a high capacity and a high-cycle stability.
The lithium/nickel/cobalt/manganese composite oxide of Formula Ha may have preferably a structure wherein Ni 2+ and Ni 3+ coexist in the MO layers and some of Ni 2+ are inserted into the lithium layers. That is, in such a structure of the metal oxide, all of Ni ions inserted into the lithium layers are Ni 2+ and the oxidation number of Ni ions is not changed in the charge process.
Specifically, when Ni 2+ and Ni 3+ coexist in a Ni-excess lithium transition metal oxide, an oxygen atom-deficient state is present under given conditions (reaction atmosphere, Li content, etc.) and therefore insertion of some Ni 2+ ions into the lithium layers may occur with changes in the oxidation number of Ni.
Therefore, since Ni 2+ is inserted into and serves to support the MO layers, Ni 2+ is preferably contained in an amount enough to stably support between MO layers such that the charge stability and cycle stability can be improved to a desired level, and at the same time it is inserted in an amount not so as to hinder intercalation/deintercalation of lithium ions into/from the lithium layers such that rate characteristics are not deteriorated. Taken altogether, the mole fraction of Ni 2+ inserted and bound into the reversible layers may be preferably in a range of 0.03 to 0.07, based on the total content of Li sites present in the lithium layers.
The further preferred element composition meets the requirements of 0.45≦b≦0.65, 0.2≦c≦0.4, and 0.65≦b+c≦0.85.
The mixing ratio of the lithium/manganese spinel oxide (Formula I) and lithium/nickel/cobalt/manganese composite oxide (Formula II) is preferably in the range of 90:10 to 10:90 (w/w). If the content of the composite oxide (I) among two composite oxides is excessively low, the stability of the battery is lowered. Conversely, if the content of the composite oxide (II) is excessively low, it is undesirably difficult to achieve desired life characteristics. These facts will also be illustrated and confirmed in the following Examples and Comparative Examples hereinafter.
Methods of preparing the lithium metal composite oxides such as the lithium/manganese spinel oxides of Formula I and the lithium/nickel/cobalt/manganese composite oxides of Formula II including the composite oxides of Formula Ha can be easily reproduced by those skilled in the art based upon the compositions of the formulas and thus will not be described herein.
Hereinafter, fabrication of a cathode containing a cathode active material according to the present invention will be specifically illustrated.
First, the cathode active material of the present invention, and a binder and a conductive material in a content of 1 to 20% by weight relative to the active material are added to a dispersion solvent and the resulting dispersion is stirred to prepare an electrode paste. The paste is applied to a metal plate for a current collector which is then compressed and dried to fabricate a laminate electrode.
The cathode current collector is generally fabricated to have a thickness of 3 to 500 μtm. There is no particular limit to the cathode current collector, so long as it has high conductivity without causing chemical changes in the fabricated battery. As examples of the cathode current collector, mention may be made of stainless steel, aluminum, nickel, titanium, sintered carbon, and aluminum or stainless steel which was surface-treated with carbon, nickel, titanium or silver. The current collector may be fabricated to have fine irregularities on the surface thereof so as to enhance adhesion to the cathode active material. In addition, the current collector may take various forms including films, sheets, foils, nets, porous structures, foams and non-woven fabrics.
As examples of the binder that may be utilized in the present invention, mention may be made of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), cellulose, polyvinyl alcohols, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinyl pyrollidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber, fluoro rubber and various copolymers.
There is no particular limit to the conductive material, so long as it has suitable conductivity without causing chemical changes in the fabricated battery. As examples of conductive materials, mention may be made of conductive materials, including graphite such as natural or artificial graphite; carbon blacks such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black and thermal black; conductive fibers such as carbon fibers and metallic fibers; metallic powders such as carbon fluoride powder, aluminum powder and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; and polyphenylene derivatives. Specific examples of commercially available conductive materials may include various acetylene black products (available from Chevron Chemical Company, Denka Singapore Private Limited and Gulf Oil Company), Ketjen Black EC series (available from Armak Company), Vulcan XC-72 (available from Cabot Company) and Super P (Timcal Co.).
Where appropriate, the filler may be optionally added as an ingredient to inhibit cathode expansion. There is no particular limit to the filler, so long as it does not cause chemical changes in the fabricated battery and is a fibrous material. As examples of the filler, there may be used olefin polymers such as polyethylene and polypropylene; and fibrous materials such as glass fiber and carbon fiber.
Representative examples of the dispersion solvent that can be used in the present invention may include isopropyl alcohol, N-methyl pyrrolidone (NMP) and acetone.
Uniform application of the paste of electrode materials to a metal material may be carried out by conventional methods known in the art or appropriate novel methods, taking into consideration characteristics of materials to be used. For example, preferably the electrode paste is distributed onto the current collector and is then uniformly dispersed thereon using a doctor blade. Where appropriate, distribution and dispersion of the electrode paste may also be performed in a single step. Further, application of the electrode paste may be carried out by a method selected from die casting, comma coating, screen printing and the like. Alternatively, application of the electrode paste may be carried out by molding the paste on a separate substrate and then binding it to the current collector via pressing or lamination.
Drying of the paste applied over the metal plate is preferably carried out in a vacuum oven at 50 to 200° C. for 1 to 3 days.
Further, the present invention provides a lithium secondary battery comprising an electrode assembly composed of the above-fabricated cathode and an anode, which are arranged opposite to each other with a separator therebetween, and a lithium salt-containing, non-aqueous electrolyte.
The anode is, for example, fabricated by applying an anode active material to an anode current collector, followed by drying. If desired, the anode may further optionally include other components such as conductive material, binder and filler, as described above.
The anode current collector is generally fabricated to have a thickness of 3 to 500 μm. There is no particular limit to the anode current collector, so long as it has suitable conductivity without causing chemical changes in the fabricated battery. As examples of the anode current collector, mention may be made of copper, stainless steel, aluminum, nickel, titanium, sintered carbon, copper or stainless steel having a surface treated with carbon, nickel, titanium or silver, and aluminum-cadmium alloys. Similar to the cathode current collector, the anode current collector may also be fabricated to form fine irregularities on the surface thereof so as to enhance adhesion to the anode active material. In addition, the anode current collector may take various forms including films, sheets, foils, nets, porous structures, foams and non-woven fabrics.
As examples of the anode materials utilizable in the present invention, mention may be made of carbon such as non-graphitizing carbon and graphite based carbon; metal composite oxides such as Li x Fe 2 O 3 (0≦x≦1), Li x WO 2 (0≦x≦1) and Sn x Me 1−x Me′ y O z (Me: Mn, Fe, Pb, Ge; Me′: Al, B, P, Si, Group I, Group II and Group III elements of the Periodic Table of the Elements, halogen atoms; 0<x≦1; 1≦y≦3; and 1≦z≦8); lithium metals; lithium alloys; silicon based alloys; tin based alloys; metal oxides such as SnO, SnO 2 , PbO, PbO 2 , Pb 2 O 3 , Pb 3 O 4 , Sb 2 O 3 , Sb 2 O 4 , Sb 2 O 5 , GeO, GeO 2 , Bi 2 O 3 , Bi 2 O 4 , and Bi 2 O 5 ; conductive polymers such as polyacetylene; and Li—Co—Ni based materials.
The separator is interposed between the cathode and anode. As the separator, an insulating thin film having high ion permeability and mechanical strength is used. The separator typically has a pore diameter of 0.01 to 10 μm and a thickness of 5 to 300 μm. As the separator, sheets or non-woven fabrics, or kraft papers made of an olefin polymer such as polypropylene and/or glass fibers or polyethylene, which have chemical resistance and hydrophobicity, are used. Typical examples of commercially available products for the separator may include Celgard series such as Celgard™ 2400 and 2300 (available from Hoechst Celanese Corp.), polypropylene separators (available from Ube Industries Ltd., or Pall RAI Co.) and polyethylene series (available from Tonen or Entek).
Where appropriate, a gel polymer electrolyte may be coated on the separator to increase the battery stability. Representative examples of the gel polymer may include polyethylene oxide, polyvinylidene fluoride and polyacrylonitrile.
When a solid electrolyte such as a polymer is employed as the electrolyte, the solid electrolyte may also serve as both the separator and electrolyte.
The lithium salt-containing non-aqueous electrolyte is composed of a non-aqueous electrolyte and lithium. As the non-aqueous electrolyte, a non-aqueous electrolytic solution, organic solid electrolyte and inorganic solid electrolyte may be utilized.
As examples of the non-aqueous electrolytic solution that can be used in the present invention, mention may be made of non-protic organic solvents such as N-methyl-2-pyrollidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, ethylmethyl carbonate, gamma-butyrolactone, 1,2-dimethoxy ethane, 1,2-diethoxy ethane, tetrahydroxy Franc, 2-methyl tetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, 4-methyl-1,3-dioxene, diethylether, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, methyl acetate, phosphoric acid triester, trimethoxy methane, dioxolane derivatives, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, ether, methyl propionate and ethyl propionate.
As examples of the organic solid electrolyte utilized in the present invention, mention may be made of polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphoric acid ester polymers, poly agitation lysine, polyester sulfide, polyvinyl alcohol, polyvinylidene fluoride, and polymers containing ionic dissociation groups.
As examples of the inorganic solid electrolyte utilized in the present invention, mention may be made of nitrides, halides and sulphates of lithium such as Li 3 N, LiI, Li 5 NI 2 , Li 3 N—LiI—LiOH, LiSiO 4 , LiSiO 4 —LiI—LiOH, Li 2 SiS 3 , Li 4 SiO 4 , Li 4 SiO 4 —LiI—LiOH and Li 3 PO 4 -Li 2 S—SiS 2 .
The lithium salt is a material that is readily soluble in the above-mentioned non-aqueous electrolyte and may include, for example, LiCl, LiBr, LiI, LiClO 4 , LiBF 4 , LiB 10 Cl 10 , LiPF 6 , LiCF 3 SO 3 , LiCF 3 CO 2 , LiAsF 6 , LiSbF 6 , LiAlCl 4 , CH 3 SO 3 Li, CF 3 SO 3 Li, LiSCN, LiC(CF 3 SO 2 ) 3 , (CF 3 SO 2 ) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide.
Additionally, in order to improve charge/discharge characteristics and flame retardancy, for example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, n-glyme, hexaphosphoric triamide, nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinone, N,N-substituted imidazolidine, ethylene glycol dialkyl ether, ammonium salts, pyrrole, 2-methoxy ethanol, aluminum trichloride or the like may be added to the non-aqueous electrolyte. If necessary, in order to impart incombustibility, the non-aqueous electrolyte may further include halogen-containing solvents such as carbon tetrachloride and ethylene trifluoride. Further, in order to improve high-temperature storage characteristics, the non-aqueous electrolyte may additionally include carbon dioxide gas.
EXAMPLES
Now, the present invention will be described in more detail with reference to the following Examples. These examples are provided only for illustrating the present invention and should not be construed as limiting the scope and spirit of the present invention.
Example 1
A substituted lithium/manganese spinel oxide of Li 1+x Mn 1.95 Al 0.05 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 Co 1/3 Mm 1/3 O 2 were mixed in a weight ratio of 1:1 to thereby prepare a cathode active material. The cathode active material was mixed with 5% by weight of carbon black and 5% by weight of PVdF as a binder, and stirred with NMP as a solvent. The resulting mixture was coated on aluminum foil as a metal current collector which was then dried in a vacuum oven at 120° C. for more than 2 hours, thereby fabricating a cathode.
An electrode assembly was fabricated using the thus-fabricated cathode, an anode which was fabricated by coating mesocarbon microbeads (MCMBs) as artificial graphite on copper foil, and a porous separator made of polypropylene. The electrode assembly was placed in a pouch case to which electrode leads were then connected. Thereafter, as an electrolyte, a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (1:1, vv), in which 1M LiPF 6 salt was dissolved, was injected thereto, followed by sealing the case to assemble a lithium secondary battery.
The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results thus obtained are given in Table 1 below.
Example 2
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mm 1.9 Al 0.1 O 4 , instead of using Li 1+x Mm 1.95 Al 0.05 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 1 below.
Example 3
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mm 1.8 Al 0.2 O 4 , instead of using Li 1+x Mm 1.95 Al 0.05 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 1 below.
Example 4
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.95 Mg 0.05 O 4 , instead of using Li 1+x Mn 1.95 Al 0.05 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 1 below.
Example 5
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Mg 0.1 O 4 , instead of using Li 1+x Mn 1.95 Al 0.05 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 1 below.
Example 6
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.8 Mg 0.2 O 4 , instead of using Li 1+x Mn 1.95 Al 0.05 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 1 below.
Comparative Example 1
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a non-substituted lithium/manganese spinel oxide of Li 1+x Mn 2 O 4 , instead of using Li 1+x Mm 1.95 Al 0.05 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 1 below.
TABLE 1
Substitution
Life characteristics
Substituent
amount
(Capacity at 300 cycles
metal ions
of metal ions (y)
relative to initial capacity, %)
Ex. 1
Al
0.05
78
Ex. 2
Al
0.1
84
Ex. 3
Al
0.2
85
Ex. 4
Mg
0.05
80
Ex. 5
Mg
0.1
82
Ex. 6
Mg
0.2
83
Comp. Ex. 1
—
0
56
As can be seen from Table 1, in the composite oxide mixtures of the cathode active materials, substitution of a manganese (Mn) site of the lithium/manganese spinel oxide with aluminum (Al) or magnesium (Mg) has led to significant improvements in life characteristics of the battery. In addition, the higher substitution amounts (y-value) of metal ions have led to further improvements in life characteristics. However, as will be seen in Comparative Examples 2 and 3 hereinafter, it was confirmed that when the substitution amount, i.e., the y value, exceeds 0.2, the initial capacity of the battery is decreased.
Comparative Example 2
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.7 Al 0.3 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V, and the initial capacity of the battery was measured and compared with the secondary battery of Example 1. The results have confirmed 14% decrease of battery capacity, relative to the initial capacity of the secondary battery of Example 1.
Comparative Example 3
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a lithium/manganese spinel oxide of Li 1+x Mn 1.7 Mg 0.3 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V, and the initial capacity of the battery was measured and compared with the secondary battery of Example 1. The results have confirmed 24% decrease of battery capacity, relative to the initial capacity of the secondary battery of Example 1.
Example 7
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 Co 1/3 Mm 1/3 O 2 in a weight ratio of 90:10. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
Example 8
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 Co 1/3 Mm 3 O 2 in a weight ratio of 70:30. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
Example 9
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 CO 1/3 Mn 1/3 O 2 in a weight ratio of 50:50 (1:1). The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
Example 10
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 Co 1/3 Mm 1/3 O 2 in a weight ratio of 30:70. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
Example 11
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 Co 1/3 Mm 1/3 O 2 in a weight ratio of 10:90. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
Comparative Example 4
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using only a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
Comparative Example 5
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using only a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 1/3 CO 1/3 Mn 1/3 O 2 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 2 below.
TABLE 2
Weight ratio
Weight ratio
Life
of 10% Al-
of lithium/
characteristics
substituted
nickel/cobalt/
(Capacity at 300
lithium/
manganese
cycles relative
manganese
composite
to initial
spinel
oxide
capacity, %)
Ex. 7
90
10
81
Ex. 8
70
30
82
Ex. 9
50
50
84
Ex. 10
30
70
82
Ex. 11
10
90
81
Comp. Ex. 4
100
0
64
Comp. Ex. 5
0
100
80
As can be seen from Table 2, life characteristics of the battery began to improve when more than 10% lithium/nickel/cobalt/manganese composite oxide was added to the Al-substituted lithium/manganese spinel oxide, and it could be confirmed that the thus-obtained life characteristics are similar to life characteristics achieved upon addition of more than 30% lithium/nickel/cobalt/manganese composite oxide. However, an excessively high content of the lithium/nickel/cobalt/manganese composite oxide may result in relatively low safety of the battery and therefore it is preferred to use the lithium/nickel/cobalt/manganese composite oxide in an amount of less than 90%.
Example 12
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 in a weight ratio of 90:10. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 3 below.
Example 13
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 in a weight ratio of 70:30. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 3 below.
Example 14
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 in a weight ratio of 50:50 (1:1). The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 3 below.
Example 15
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 in a weight ratio of 30:70. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 3 below.
Example 16
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mm 0.4 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 in a weight ratio of 10:90. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 3 below.
Comparative Example 6
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using only a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 . The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 3 below.
TABLE 3
Weight ratio of
Weight ratio of
Life characteristics
10% Al-substituted
lithium/nickel/
(Capacity at 300
lithium/manganese
cobalt/manganese
cycles relative to
spinel
composite oxide
initial capacity, %)
Ex. 12
90
10
81
Ex. 13
70
30
81
Ex. 14
50
50
84
Ex. 15
30
70
82
Ex. 16
10
90
80
Comp. Ex. 4
100
0
64
Comp. Ex. 6
0
100
78
As can be seen from Table 3, life characteristics of the battery began to improve when more than 10% lithium/nickel/cobalt/manganese composite oxide was added to the Al-substituted lithium/manganese spinel, and it could be confirmed that the thus-obtained life characteristics are similar to life characteristics achieved upon addition of more than 30% lithium/nickel/cobalt/manganese composite oxide. However, an excessively high content of the lithium/nickel/cobalt/manganese composite oxide may result in relatively low safety of the battery and therefore it is preferred to use the lithium/nickel/cobalt/manganese composite oxide in an amount of less than 90%.
Example 17
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 in a weight ratio of 70:30. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 4 below.
Example 18
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 in a weight ratio of 50:50. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 4 below.
Example 19
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 in a weight ratio of 30:70. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 4 below.
Example 20
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.47 Mn 0.30 Co 0.23 O 2 in a weight ratio of 50:50. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 4 below.
Example 21
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Al 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+z Ni 0.61 Mn 0.21 Co 0.18 O 2 in a weight ratio of 50:50. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 4 below.
Example 22
A lithium secondary battery was assembled in the same manner as in Example 1, except that a cathode active material was prepared using a substituted lithium/manganese spinel oxide of Li 1+x Mn 1.9 Mg 0.1 O 4 and a lithium/nickel/cobalt/manganese composite oxide of Li 1+x Ni 0.53 Mn 0.26 Co 0.21 O 2 in a weight ratio of 50:50. The thus-fabricated lithium secondary battery was subjected to charge/discharge cycling in a voltage range of 3.0 to 4.2V and life characteristics of the battery were measured. The results are given in Table 4 below.
TABLE 4
Life characteristics
Substituted
lithium/nickel/
(Capacity at 300 cycles
lithium/manganese
cobalt/manganese
relative to initial
spinel (weight ratio)
composite oxide (weight ratio)
capacity, %))
Ex. 17
L 1+x Mn 1.9 Al 0.1 O 4 (70)
L 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 (30)
86
Ex. 18
L 1+x Mn 1.9 Al 0.1 O 4 (50)
L 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 (50)
88
Ex. 19
L 1+x Mn 1.9 Al 0.1 O 4 (30)
L 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 (30)
87
Ex. 20
L 1+x Mn 1.9 Al 0.1 O 4 (50)
L 1+z Ni 0.47 Mn 0.30 Co 0.23 O 2 (50)
85
Ex. 21
L 1+x Mn 1.9 Al 0.1 O 4 (50)
L 1+z Ni 0.61 Mn 0.21 Co 0.18 O 2 (50)
86
Ex. 22
L 1+x Mn 1.9 Mg 0.1 O 4 (50)
L 1+z Ni 0.53 Mn 0.26 Co 0.21 O 2 (50)
86
As can be seen from Table 4, life characteristics of the battery further improved when the lithium/nickel/cobalt/manganese composite oxide according to Formula IIa was added to the substituted lithium/manganese spinel compared to the case of adding Li 1+z Ni 1/3 CO 1/3 Mn 1/3 O 2 (Examples 8-10) or Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O 2 (Examples 13-15). This is because the structural stability of the lithium/nickel/cobalt/manganese composite oxide according to Formula IIa contributes to the life characteristics.
INDUSTRIAL APPLICABILITY
As apparent from the above description, a lithium secondary battery using a mixture of a manganese spinel oxide having a substitution of a manganese (Mn) site with a certain metal element and a certain lithium/nickel/cobalt/manganese composite oxide, according to the present invention, as a cathode active material, can secure safety of the battery and improve a service life thereof, even under high current, short period charge/discharge cycle conditions.
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. | Provided is a non-aqueous electrolyte-based, high-power lithium secondary battery having a long service life and superior safety at both room temperature and high temperature, even after repeated high-current charging and discharging. The battery comprises a mixture of a lithium/manganese spinel oxide having a substitution of a manganese (Mn) site with a certain metal ion and a lithium/nickel/cobalt/manganese composite oxide, as a cathode active material. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 08/692,129 filed Aug. 5, 1996 now U.S. Pat. No. 5,776,977, issued Jul. 7, 1998, which is a division of application Ser. No. 08/444,518 filed May 19, 1995, now U.S. Pat. No. 5,589,514 issued Dec. 31, 1996, which was a continuation of application Ser. No. 08/002,863 filed Jan. 14, 1993, abandoned, all of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to novel arylcycloalkyl derivatives, their production, and their use.
2. Description of Related Art
The chalcones of the following general formula Ia are known by the following prior art: ##STR2## 1. J.P. 281022--Compounds of formula Ia, wherein R 1 =substituted phenyl,
R 2 =OH,
a=single or double bond,
R 3 =OH,
R 4a =H, isoprenyl or isopentyl,
and are effective in treatment of diseases caused by hypersecretion of androgens, e.g., prostatomegaly, alopecia in males, acne vulgaris or seborrhoea.
2. J.P. 026775--Compounds of formula Ia wherein
R 1 =substituted phenyl,
R 2 =H, OH, acetoxy, carboxymethoxy or methoxycarbonylmethoxy,
R 3 =OH, methoxy, benzyloxy, H,
R 4a =H, isoprenyl or isopentyl,
and possess anti-hyaluronidase activity.
3. J.P. 142166--Compounds of formula Ia wherein
R 1 =substituted phenyl,
R 2 =OH, acetoxy, carboxymethoxy, methoxycarboxylmethoxy,
R 3 =OH, methoxy, H,
a=single or a double bond,
R 4a =isoprenyl, isopentyl, n-propyl or H,
and are useful as aldose reductase inhibitors--used to treat diabetic complications such as cataracts, retinitis, nerve disorder or kidney disease.
4. J.P. 248389--Compounds of formula Ia wherein
R 1 =substituted phenyl,
R 2 =OH,
R 3 =OH,
a=a double bond,
R 4a =H,
and are useful as aldose reductase inhibitors--for treatment of diabetes mellitus complications.
5. J.P. 144717--Compounds of formula Ia wherein
R 1 =substituted phenyl,
R 2 =H or OH,
R 3 =H or OH,
a=a double bond,
R 4a =H or OH,
and are useful as c-kinase inhibitors and antitumor agents.
6. EP 150166--Compounds of formula Ia wherein
R 1 =substituted phenyl,
R 2 =H, halogen, lower alkyl, lower alkoxy, CN, carboxy, nitro,
R 3 =H, halogen, lower alkyl, lower alkoxy, CN, carboxy, nitro, hydroxy, substituted acetic acid derivative,
a=a double bond,
R 4a =as in R 3 ,
and having inhibitory effect on hydroxy-prostaglandin dehydrogenase. They may have potential local activity against gastrointestinal disorders such as gastric ulcer, and ulcerative colitis. Other potential fields of application include the treatment of rheumatoid arthritis, circulatory disorders, cancer, lack of fertility and cell regulation.
7. J.P. 167288--Compounds of formula Ia wherein
R 1 =substituted phenyl,
R 2 =H,
R 3 =OH,
a=a single bond,
R 4a =OH,
and are selective inhibitors of 5-lipoxygenase and have excellent anti-allergic activity, thus are useful as a safe anti-allergic drug such as antiasthmatic, antiphlogistic and immune activating drug.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to compounds of formula I, ##STR3## wherein R 1 =C 1 -C 6 -alkyl, substituted C 1 -C 6 -alkyl, C(O)O--C 1 -C 4 -alkyl, C(O)OH, or a residue selected from ##STR4## wherein R 5 is one, two, three, or four of the residues which are independent of each other and are selected from the group consisting of H, C 1 -C 6 -alkyl, substituted C 1 -C 6 -alkyl, hydroxy, C 1 -C 6 -alkoxy, carboxy, cyano, NHC(O)C 1 -C 3 -alkyl, --OC 1 -C 3 -alkyl-phenyl, --OCH 2 --O--, C 1 -C 4 -alkyl-O--C 1 -C 4 -alkyl, --O--(O)--C 1 -C 4 -alkyl, --C(O)--O--C 1 -C 4 -alkyl, halogen, amino, nitro, --NH--C 1 -C 4 -alkyl, --N--(C 1 -C 4 -alkyl) 2 , and --C 1 -C 4 -alkyl-R 6 wherein R 6 is a residue selected from ##STR5## X is O, S, N--H, N--C 1 -C 6 -alkyl; R 2 is H, C 1 -C 6 -alkyl, --C(O)--C 1 -C 6 -alkyl;
R 3 is one, two, or three of the residues which are independent of each other and are selected from the group consisting of H, C 1 -C 6 -alkyl, --C(O)--C 1 -C 6 -alkyl, --C(O)--O--C 1 -C 6 -alkyl, OH, O--C 1 -C 6 -alkyl, --O--C(O)--C 1 -C 6 -alkyl, halogen;
R 4 is H, --OH, --O--C 1 -C 6 -alkyl, --O--C(O)--C 1 -C 6 -alkyl, --C(O)--OH, --C(O)--O--C 1 -C 6 -alkyl, O--C(O)--(C 1 -C 4 -alkyl-NH 2 , O--C(O)--(C 1 -C 4 -alkyl)-NH--(C 1 -C 4 -alkyl), O--C(O)--(C 1 -C 4 -alkyl)-N--(C 1 -C 4 -alkyl) 2 ;
n 0, 1 or 2; and
a represents an optional additional single bond,
and to the physiologically tolerable salts thereof.
Preferred compounds are compounds of formula II ##STR6## wherein R 1 , R 2 , R 3 , R 4 and a are as previously defined, and the physiologically tolerable salts thereof.
Among this group of compounds, those are preferred in which R 1 is ##STR7## R 5 denoting H, C 1 -C 6 -alkyl, substituted C 1 -C 6 -alkyl, hydroxy, C 1 -C 3 -alkoxy, halogen, C 1 -C 4 -alkyl-R 6 wherein R 6 stands for ##STR8## R 4 denotes H, OH or --O--C(O)--(C 1 -C 4 -alkyl)-NH 2 ; X stands for O, NH, S, N--C 1 -C 6 -alkyl; and
a stands for an optional additional bond,
and the physiologically tolerable salts thereof.
Particularly preferred are compounds of formula III ##STR9## wherein R 2 is H or C 1 -C 3 -alkyl,
R 5 denotes one or two halogens or one or two C 1 -C 6 -alkyl or C 1 -C 3 -alkoxy groups, and a denotes an optional additional single bond, and the physiologically tolerable salts thereof.
The above term substituted alkyl means alkyl, preferably C 1 -C 3 -alkyl, substituted by preferably one halogen, hydroxy, C 1 -C 3 -alkoxy, amino, C 1 -C 4 -alkylamino, di-(C 1 -C 4 -alkyl)-amino, carbonyl or carboxy-C 1 -C 4 -alkyl.
The compounds of the invention contain two asymmetric centers, designated with asterisks in formula II, at the points of attachment of R 4 , (e.g., formula II, when R 4 =H) and of the aryl group on the carbocyclic ring; therefore, four isomers are possible, designated individually as the cis-(+), cis-(-), trans (+), and trans-(-) forms. The present invention includes each of the four isomers individually or as mixtures of two or more of the four isomers.
Examples of particularly preferred compounds are:
1. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-chlorophenyl))prop-2-enoyl]-phenylcyclohexanol.
2. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2-chlorophenyl))prop-2-enoyl]-phenylcyclohexanol.
3. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-chlorophenyl))prop-2-enoyl]-phenylcyclohexanol.
4. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2-bromophenyl))prop-2-enoyl]-phenylcyclohexanol.
5. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl))prop-2-enoyl]-phenylcyclohexanol.
6. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-bromophenyl))prop-2-enoyl]-phenylcyclohexanol.
7. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-fluorophenyl))prop-2-enoyl]-phenylcyclohexanol.
8. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2-methylphenyl))prop-2-enoyl]-phenylcyclohexanol.
9. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-methylphenyl))prop-2-enoyl]-phenylcyclohexanol.
10. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2,3-dichlorophenyl))prop-2-enoyl]-phenylcyclohexanol.
11. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2,6-dichlorophenyl))prop-2-enoyl]-phenylcyclohexanol.
12. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2,6-dichlorophenyl))prop-2-enoyl]-phenylcyclohexanol.
13. trans-(+)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-chlorophenyl))prop-2-enoyl]phenylcyclohexanol.
14. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-chlorophenyl))prop-2-enoyl]phenylcyclohexanol.
15. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-methoxyphenyl))prop-2-enoyl]phenylcyclohexanol.
16. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-methoxyphenyl))prop-2-enoyl]phenylcyclohexanol.
17. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-chloro-3-nitrophenyl))prop-2-enoyl]phenylcyclohexanol.
18. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-chloro-3-nitrophenyl))prop-2-enoyl]phenylcyclohexanol.
19. trans-(+/-)-1-[4,6-Dimethoxy-2-hydroxy-3-(2-(β-amino)acetoxy)cyclohexyl]phenyl-1-(3-(3,4-dimethoxy)phenyl)propanone hydrochloride.
20. trans(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-enoyl)-phenyl]cyclohexyl-2-(S)-carb-tertbutoxyamino propanoate hydrochloride.
Further examples of particularly preferred compounds are:
21. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-amino acetate hydrochloride monohydrate.
22. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-amino acetate hydrochloride monohydrate.
23. trans-(+)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-amino acetate hydrochloride monohydrate.
24. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-(S)-amino propanoate.
25. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-(S)-amino propanoate hydrochloride.
26. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-(S)-amino propanoate hydrochloride.
27. cis-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl))prop-2-(E)-enoyl]phenylcyclohexanol.
28. trans-(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl))prop-2-(E)-enoyl]phenylcyclohexanol.
29. trans-(+)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl))prop-2-(E)-enoyl]phenylcyclohexanol.
30. trans-(+/-)-2-[6-Methoxy-2-hydroxy-3-(3-(3-bromophenyl))prop-2-(E)-enoyl]phenylcyclohexanol.
31. trans-(+/-)-2-[2,6-Dimethoxy-4-hydroxy-3-(3-(3-bromophenyl))prop-2-(E)-enoyl]phenylcyclohexanol.
32. trans-(+/-)-2-[2-Hydroxy-4-methoxy-3-(3-(3-bromophenyl))prop-2-(E)-enoyl)phenylcyclohexanol hemihydrate.
33. trans-(+/-)-1-[4,6-Dimethoxy-2-hydroxy-3-(2-(β-amino)acetoxy)cyclohexyl]phenyl-(3-(3,4-dimethoxy)phenyl)propanone hydrochloride monohydrate.
34. trans-(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(2,5-dimethylphenyl))prop-2-(E)-enoyl]phenylcyclohexanol monohydrate.
A further subject of the instant application is a process for the production of compounds of formula I as described above wherein a compound of formula V ##STR10## A) is converted into a compound of formula VI, ##STR11## R 4 denoting OH by treatment with a borane-solvent-complex followed by oxidation or
B) to get a compound of formula VI, a compound of formula V is treated with a peracid and the epoxide thus produced is treated with a hydride reagent or
C) the compound of formula VI is produced by condensation of a suitable arene with cyclohexene oxide in the presence of an acid catalyst and
D) a compound of formula VI is treated with acetic anhydride and a mineral acid to give a compound of formula VII, ##STR12## wherein R 2 is methyl and R 4 is O--C(O)--Me and E) a compound of formula VII as described under D) is demethylated by treatment with a Lewis acid or a demethylating agent to give a compound of formula VII wherein R 2 denotes H and R 4 denotes OC(O)Me and
F) a compound of formula VII wherein R 2 denotes H and R 4 denotes OH is produced by treatment of a compound produced under E) with dilute alkali, and
G) the compound of formula VII is converted into a compound of formula I (a=additional bond) by treatment with an appropriate aldehyde in the presence of a base and the compound of formula I (a=no additional bond) is produced by hydrogenation of the compound of formula I (a=additional bond), R 1 , R 2 and R 3 , where not explained explicitly, having the meaning as indicated above.
H) a compound of the formula II wherein R 4 is an amino acid ester can be prepared by treating a compound of the formula II (wherein R 4 is --OH) with an appropriate N-protected amino acid in the presence of dicyclohexyl carbodiimide and a weak base, for example, 2,4-dimethyl amino pyridine. The ester obtained can be subjected to deprotection of the amino function using a weak acid. The weak acid can be formic acid in the presence of anisaldehyde. The formate salt can be exchanged with the hydrochloride salt.
The compounds of formula V are prepared by methods known to a person skilled in the art. Typically, they are prepared by addition of aryllithiums of formula IV to cyclohexanone followed by acid catalyzed dehydration, R 2 and R 3 having the meaning as indicated above. ##STR13##
A suitable borane-solvent complex for step A of the above sequence is, for instance, borane-tetrahydrofuran or borane dimethylsulfide. The oxidation can be carried out using alkaline hydrogen peroxide. A suitable peracid for step B is, for instance, chloroperbenzoic acid. An example of a suitable hydride reagent is lithium aluminum hydride.
Step C can be carried out using as arene, 1.3.5-trimethoxy-benzene, for example, the acid catalyst being aluminum chloride.
The mineral acid needed for step D can be, for instance, phosphoric acid.
Step E can be carried out using, for example, as Lewis acid boron tribromide and as demethylating agent, metal thiolates. The preferred dilute alkali for step F is 2N sodium hydroxide solution.
The base in the presence of which step G is carried out can be sodium hydroxide, for example.
The products according to the above reaction steps can be used for further reactions to compounds according to the instant invention. Most of said reactions can be carried out according to procedures described in European patent application 0 241 003. Additional information about starting products, intermediates and derivatization reactions can be obtained from the patent literature mentioned in the introduction.
The physical constants of some of the preferred compounds of the present invention are listed in Tables 1, 1A and 2.
TABLE 1______________________________________ ##STR14##Compound Sign ofNo. R.sub.5 R.sub.2 a m.p. ° C. Rotation______________________________________ 1. H H Δ 2',3' 183-185 ± 2. 2-Cl H " 204-206 " 3. 3-Cl H " 170 " 4. 4-Cl H " 221 " 5. 2-Br H " 203 " 6. 3-Br H " 171 " 7. 4-Br H " 222 " 8. 4-F H " 215-216 " 9. 2,3-Cl.sub.2 H " 216 "10. 2,4-Cl.sub.2 H " 226-228 "11. 2,6-Cl.sub.2 H " 197 "12. 2-Me H " 199 "13. 4-Me H " 213 "14. 4-OMe H " 210 "15. 4-Cl Me " 175 "16. 4-Cl H H,H 190 "17. 4-F H H,H 169 "18. 3,4-Cl.sub.2 H Δ2',3' 202 "19. 3,5-Cl.sub.2 H " 227 "20. 2-OMe H " 215 "21. 3-OMe " 178 "22. 3,4-(OMe).sub.2 H " 194 "23. 2,5-(OMe).sub.2 H " 185 "24. 2,4-(OMe).sub.2 H " 224-225 "25. 2,4,6-(OMe).sub.3 H " 162 "26. 4-COOH H " 240 "27. 4-N(CH.sub.3).sub.2 H " 187 "28. 4 Cl,3-NO.sub.2 H " 215 "29. 3-OH H " 210 "30. 4-OH H " 210 "31. 2-OH H " 209 "32. 4-CF.sub.3 H " 177 "33. 4-NHCOCH.sub.3 H " 274 "34. 3,4-(OMe).sub.2 H H,H 151 "35. 2,4,6-(OMe).sub.3 H H,H 132 "36. 2-OH H H,H 190 "37. 3-OH H H,H 63 "38. 4-OH H H,H 216 "39. 3,4-(OH).sub.2 H H,H 201 "40. 2-CH.sub.3 H H,H 157 "41. 3,4-(OCH.sub.2 Ph).sub.2 H Δ'2,'3 173 "42. 3,4-O--CH.sub.2 --O-- H Δ'2,'3 185 "43. 4-Cl H " 231 (+)44. 4-Cl H " 231 (-)45. 4-Cl,3-NO.sub.2 H " 235 (+)46. 4-Cl,3-NO.sub.2 H " 235 (-)47. 3-OMe H " 191 (+)48. 3-OMe H " 191 (-)49. 3,4-(OMe).sub.2 H " 195 (+)50. 3,4-(OMe).sub.2 H " 195 (-)51. 2,3-Cl.sub.2 H " 217 (+)52. 2,3-Cl.sub.2 H " 217 (-)______________________________________
TABLE 1A__________________________________________________________________________Compounds of formula II in which R.sub.3 = 4,6-(OCH.sub.3).sub.2Compound Sign ofNo. R.sub.1 a R.sub.2 R.sub.4 m.p. ° C. Rotation__________________________________________________________________________1. 2-Thienyl Δ2',3' H OH 179-180 (±)2. 2-Furyl " H OH "3. 4-Nitrophenyl " H --OCOCH.sub.3 175 "4. 4-Cyanophenyl " H --OCOCH.sub.3 172 "5. 4-Chlorophenyl " H --OCOCH.sub.2 NH.sub.2 --HCl 152 "6. 3,4-Dimethoxy- " H --OCOCH.sub.2 NH.sub.2 --HCl 136-138 " phenyl__________________________________________________________________________
The physical constants of further preferred compounds of the present invention are listed in Table 2.
TABLE 2__________________________________________________________________________ (II) ##STR15## Activity (Concn.)No R.sub.1 a R.sub.2 R.sub.3 R.sub.4 *1 *2 m.p. ° C. Rot IL-1 Rel.__________________________________________________________________________ Inhib. 1 3-Bromophenyl Δ2',3' H 4,6-(OCH.sub.3).sub.2 --OCOCH.sub.3 trans 173-74 (+/-) 41% (10 μM) 2. 3-Bromophenyl " H " --OCOCH.sub.2 N(CH.sub.3).sub.2.HCl " 217-18 (+/-) 50% (17 μM) 3. 3-Bromophenyl " H " --OCOCH.sub.2 NH.sub.2.HCl " 140-42 (+/-) 63% (17 μM) 4. 3-Bromophenyl " H " ##STR16## " 224-47 (+/-) 43% (16 μM) 5. 3-Bromophenyl " H " --OCOCH.sub.2 NH.sub.2.HCl R,S 139-41 (-) 95% (1 μM) 6. 3-Bromophenyl " H " --OCOCH.sub.2 NH.sub.2.HCl S,R 138-39 (+) 88% (1 μM) 7. 3-Bromophenyl " H " --OCO--(S)--CH(NH.sub.2)CH.sub.3.HCl trans 122-24 (+/-) 35% (1 μM) 8. 3-Bromophenyl " H " --OCO--(S)--CH(NH.sub.2)CH(CH.sub.3).sub.2.HCl " (+/-) ND 9. 3-Bromophenyl " H " --OCO--(S)--CH(NH.sub.2)CH.sub.3.HCl R,S 138-40 (-) 55% (5 μM)10. 3-Bromophenyl " H " --OCO--CH(NH.sub.2)CH.sub.3.HCl S,R 130-32 (-) 72% (5 μM) 3-Bromophenyl Δ2',3' H 4,6-(OCH.sub.3).sub.2 --OH cis 175-76 (+/-) 90% (10.8 μM) 3-Bromophenyl H,H H " --OH trans 124-25 (+/-) 26% (10.5 μM) 3-Bromophenyl Δ2',3' H 4-OH,6-OCH.sub.3 --OH " 215-17 (+/-) 22% (11.6 μM) 3-Bromophenyl " H 4,6-(OCH.sub.3).sub.2 --OH R,S 156-57 (-) 50% (0.3 μM) 3-Bromophenyl " H " --OH S,R, 154 (+) 50% (0.3 μM) 3-Bromophenyl " H 6-OCH.sub.3 --OH trans 148-50 (+/-) 81% (11.6 μM) 3-Bromophenyl " CH.sub.3 4-OH,6-OCH.sub.3 --OH " 141-42 (+/-) 71% (10.8 μM) 3-Bromophenyl " H 4-OCH.sub.3 --OH " 164 (+/-) 71% (5 μM) 3,4-Dimethoxyphenyl H,H H 4,6-(OCH.sub.3).sub.2 --OCOCH.sub.2 NH.sub.2.HCl " 136-38 (+/-) 51% (10 μM)20. 3-Methylphenyl Δ2',3' H " --OH " 148 (+/-) 49% (10 μM) 2,5-Dimethylphenyl " H " --OH " 197 (+/-) 96% (10 μM) 4-Chlorophenyl " H " H -- 208 (+/-) 30% (12 μM) 2,4-Dimethyl phenyl " H " --OH trans 211 (+/-) ND 4-Methylphenyl H,H H " --OH " 165 (+/-) ND 3-Methoxy phenyl H,H H " --OH " 112 (+/-) ND 3-Bromo-4,5- Δ2',3' H " --OH " 135 (+/-) 50% (9.5 μM) Dimethoxyphenyl 3-Bromophenyl " H " --OH " 74-76 (+/-) 52% (1 μM) 3-Aminophenyl " H " --OH " 152-58 (+/-) 33% (1__________________________________________________________________________ μM)
The novel compounds of the present invention display interesting pharmacological activity when tested in pharmacological models; Compound Nos. 4 and 6 of Table 1 will be used in the examples as representative compounds.
As shown in the examples, the instant compounds have antiinflammatory properties. The compounds are particularly useful to inhibit or antagonize the responses mediated by endogenous molecules such as lipoxygenases and/or leukotrienes, interleukins and protein kinase C. The compounds of the invention, alone or in the form of a suitable formulation, are thus useful as medicaments in the treatment of inflammatory conditions, in particular chronic inflammatory conditions such as rheumatoid arthritis, osteoarthritis, asthma and malignancies.
Accordingly, other subjects of the instant invention are the use and methods of use to treat and prevent the above-mentioned inflammatory conditions by administration of an effective amount of one or more compounds of the instant invention. Furthermore, pharmaceuticals containing one or more compounds as explained above are a subject of this invention. Said pharmaceuticals can be produced and administered according to methods known in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph illustrating the effect of Compound 4 of Table 1 as inhibitor of LPS stimulated IL-1 alpha;
FIG. 2 is a graph illustrating the effect of Compound 9 of Table 2 at varying dosages on adjuvant arthritis in rats (uninjected paw);
FIG. 3 is a graph comparing the effect of Compound 6 of Table 1 and Compound 9 of Table 2 on adjuvant arthritis in rats (uninjected paw);
FIG. 4 is a graph illustrating the effect of Compound 9 of Table 2 on EAE (survival rate in %) in guinea pigs; and
FIG. 5 is a graph illustrating the effect of Compound 9 of Table 2 on EAE (clinical grading) in guinea pigs.
The following examples as well as the appended claims further illustrate the instant invention.
DETAILED DESCRIPTION OF THE INVENTION
EXAMPLE 1
Inhibition of Leukotriene Induced Contraction of Isolated Guinea Pig Ileum
Guinea pigs of either sex weighing 300-350 g were sensitized with a suspension of aluminum hydroxide gel and egg albumin. After 21 days, each animal was exposed to 0.5% egg albumin aerosol in an air tight perspex chamber and only those animals which developed allergic bronchoconstriction were selected for further experiment.
The animals were tested for one week after antigenic exposure and then sacrificed by head blow and cutting carotid arteries. The lung was quickly removed and placed in aerated Tyrode solution kept at 37° C. The lung was cut into uniform strips and each strip was placed in an organ bath containing isolated guinea pig ileum connected to potentiometric recorder through isotonic transducer in the presence of Tyrode solution kept at 37° C. After a stabilizing period of 30 minutes, the reactivity of ileum to histamine was confirmed by challenging it with 100 ng-200 ng/ml of histamine. The perfusion fluid was then replaced by Tyrode solution containing Atropine (10 -7 M), Mepyramine maleate (10 -7 M) and methylsergide (10 -7 M). Three minutes later, lung strip was challenged by egg albumin (25 μg/ml) and release of leukotrienes was monitored in terms of slow contraction of ileum. The ileum was allowed to contract for 10-15 minutes when a plateau was achieved. The test compound (compound 4 of Table 1) was then added to observe the relaxation.
The specificity of leukotriene antagonism was determined by inducing contraction of guinea pig ileum with agonists like histamine, acetylcholine and KC1. Compounds having specific effect against lipoxygenase products induced contraction normally would not show any inhibition of histamine, acetylcholine and KC1 induced contraction. The data are shown in Table 3.
TABLE 3______________________________________Effect of Compound No. 4 on isolated guinea pig ileumprecontracted with leukotrienes.Conc. (M) % Relaxation App. IC.sub.50 (M)______________________________________ 1.2 × 10.sup.-6 36.81.68 × 10.sup.-6 50.5 1.68 × 10.sup.-6 2.4 × 10.sup.-6 62.4 7.2 × 10.sup.-6 68.0______________________________________
No effect on histamine and KC1 induced contraction up to 7.11×10 -5 M.
Compound 4 as representative of the novel compounds of the present invention inhibits the contractions induced by leukotrienes.
EXAMPLE 2
Inhibition of Cotton Pellet Granuloma in Rats
This model permits the evaluation of a compound's potential to inhibit artificially induced granuloma. The implantation of carrageenin impregnated cotton pellets results in production of large, well-defined granuloma which are easily dissected. The potency of the compounds are assessed by measuring the reduction in granuloma tissue formation.
Preparation of Saline and Carrageenin Cotton Pellets
Cotton wool pellets weighing 40 mg were used for sterilization. Half the number of pellets were dipped in saline and the remaining in 1% aqueous solution (Viscarin® type 402, Marine Colloids Inc. Springfield) until they were soaked well, then squeezed slightly to remove excess saline or carrageenin.
Pellets were dried overnight under a lamp. The pellets in the weight range of 42-44 mg were selected.
Animal Preparation
Rats (in groups of 6, male or female, Charles River, Wistar, weighing 140-150 g) were anaesthetized with ether. The back was shaved and cleaned; swabbed with alcohol and one centimeter incision was made in the lower midback. A small channel was made bilaterally using a blunt forceps and one cotton pellet placed in each channel. Air from the incision was removed and the wound was stitched. The test compound was prepared in 0.5% carboxyl methyl cellulose and was administered orally at a dose of 10, 20 and 30 mg/kg daily for seven days. Three hours after the administration of the last dose on day 7, animals were sacrificed. The pellets were removed by cutting the skin along the dorsal midline and peeling the skin away from the bodywall in both lateral directions. The pellets were weighed and then placed in drying oven at 140° C. overnight. The dry weights were then recorded and the amount of granuloma was assessed by subtracting the original pellet weight from wet weights and dry weights. The data was evaluated using the difference of left and right weights (cf. Table 4).
TABLE 4______________________________________Effect of Compound No. 4 on Cotton Pellet Granuloma in Rats. Dose mg/kg, % Inhibition of granulomaTreatment p.o. × 5 Wet wt. Dry wt.______________________________________Compound No. 4 10 21 35.6 20 54 89.0 30 64 82.8Hydrocortisone 30 20.5 37.5______________________________________
Compound 4 as representative of the compounds of the present invention inhibits the granuloma formation induced by carrageenin.
EXAMPLE 3
Inhibition of Micro-Anaphylactic Shock of Guinea Pigs
Guinea pigs of either sex weighing between 300-350 g were sensitized with egg albumin absorbed over Al(OH) 3 gel. After 21 days of sensitization, each animal was placed in an air tight perspex chamber and exposed to 0.5% egg albumin aerosol through EEL atomizer. EEL atomizer was operated by connecting it to pressurized air through a water trap and dial type sphygmomanometer at the constant air pressure of 180 mm Hg. The time of onset of asthma in seconds and recovery period in minutes was noted.
Each animal was exposed to egg albumin aerosol at an interval of 15 days to maintain the consistency of the reactivity of animals to the antigen. After 3 such control exposures, animals were subjected to drug treatment. On the day of the experiment one group of Guinea pigs consisting of 10 animals was kept as control exposing them only to 0.5% egg albumin aerosol. Another group of 10 guinea pigs was treated with Indomethacin 10 mg/kg i.p. 30 mins. before exposure to the antigen. Yet another group of 10 guinea pigs was pretreated with Indomethacin 10 mg/kg i.p. and 30 mins. after Indomethacin pretreatment the test compound (20 mg/ip) was injected. Fifteen mins. after the administration of the test compound the animals were exposed to 0.5% egg albumin aerosol. Onset time of recovery period of each group was noted (cf. Table 5).
TABLE 5______________________________________Effect of Compound No. 4 on microanaphylactic shock of guinea pigs. Onset Time Recovery periodTreatment in secs. in mins.______________________________________Control group 75 + 8.7 37 + 3.4Indomethacin treated group 82.4 + 11.5 147.8 + 3.510 mg/kg, i.p.Compound 4, 20 mg/kg.sup.-1, i.p. 149.2 + 25.1 77.6 + 4.7present invention + pretreatmentwith indomethacin,10 mg/kg, i.p.______________________________________
Compound 4 as a representative example of the novel compounds of the present invention protects the animals from bronchoconstriction induced by leukotrienes, subsequent to the exposure of egg albumin aerosol.
EXAMPLE 4
Inhibition of IL-1 Release Human Mononuclear Cells
Purification of Mononuclear Cells From Human Blood
10 ml of human blood were carefully drawn from the antecubital vein using a syringe containing 1 ml of a solution of 3.8% sodium citrate. After dilution with 10 ml PM 16 (Serva, Heidelberg, FRG) and underlayering with 15 ml Lymphoprep® (Molter GmbH), the sample was centrifuged at 400×g for 40 min at 20° C. The mononuclear cells forming a white ring between lymphoprep and plasma were carefully aspirated by a syringe, diluted 1:1 with PM 16 and centrifuged again at 400×g for 10 min. The supernatant was washed with 10 ml RPMI 1640 (Gibco, Berlin, FRG), containing additionally 300 mg/l L-glutamine, 25 mmol/l RPM 1640, containing additionally 300 mg/l L-glutamine, 25 mmol/l HEPES, 100 μg/ml streptomycin and 100 μg/ml penicillin. Finally, using a Coulter counter IT, the cell suspension was adjusted to 5×10 6 cells/ml. The cells consist of approx. 90% lymphocytes and 10% monocytes.
Stimulation of Interleukin 1 From Human Mononuclear Cells in Vitro
10 μl DMSO/water (1:10, v/v), containing the test compound, was added to 480 μl of a suspension, containing 5×10 6 mononuclear cells. The synthesis of IL-1 was stimulated by the addition of 10 μl DSMO/water (1:10, v/v), containing 0,5 μg LPS (Salmonella abortus equi, Sigma). After incubation at 37° C. for 18 hours, the samples were cooled to 0° C. and centrifuged for 1 min. in a table centrifuge. 25 μl aliquots of the supernatant were assayed for IL-1 alpha activity using a commercially available 125-J-IL-1-alpha radioimmunoassay Kit (Amersham/UK), and for IL-1 beta in a similar way using the specific test kit. Control experiments were performed as described without test compound, or with cycloheximide as a test compound.
The effect of compound 4 as inhibitor of LPS stimulated IL-1 alpha (Approx. IC 50 =200-300 nmol/l), is shown in FIG. 1.
Compound 4 as a representative example of the compounds of the present invention inhibits LPS stimulated IL-1 alpha release from human mononuclear cells in vitro.
Compounds of the instant application are prepared as described below:
EXAMPLE 5
Preparation of 1-(2,4,6-Trimethoxyphenyl)cyclohexene
An Example of Formula V Wherein R 3 =4,6-dimethoxy, R 2 =CH 3
2,4,6-Trimethoxybromobenzene (1 eqvt.) was placed in a flame dried 3-necked flask under nitrogen. Dry tetrahydrofuran (THF) (983 ml) was added and the reaction mixture was cooled to -30° C. n-BuLi (1.3 eqvt.) in hexane (commercial) was added dropwise and after the addition the reaction mixture was stirred for 30 min. Thin layer chromatographic examination at this stage indicated completion of metallation reaction. Cyclohexanone (1.1 eqvt.) diluted with equal volume of dry THF was added to the reaction mixture at -30° C. and the reaction mixture was stirred for another one hour at -30° C. and later allowed to come to room temperature. Water (150 ml) was added and extracted with ethyl acetate. The ethyl acetate layer was dried over anhydrous sodium sulfate and concentrated. The residue was added to dichloromethane and stirred for 30 min. with a catalytic amount of p-toluenesulphonic acid (9 g). The dichloromethane layer was washed with sodium bicarbonate solution followed by water and dried. The residue was crystallized from diisopropylether to give the title compound; m.p. 127° C., Yield: 64.7%.
EXAMPLE 6
Preparation of trans-(±)-2-(2,4,6-Trimethoxyphenyl)cyclohexanol
An Example of Formula VI Wherein R 2 =CH 3 , R 3 =4,6-dimethoxy and R 4 =OH
A compound of formula V (from Example 5) (1 eqvt.) was mixed with sodium borohydride (4 eqvt.) and dry THF (2,200 ml). The reaction mixture was cooled to 0° C. under nitrogen and borontrifluoride etherate (5.1 eqvt.) was added dropwise. After the addition was complete, the temperature was raised to 50° C. and stirred for 30 min. The reaction mixture was cooled to room temperature and water was added dropwise to destroy excess diborane. The organoborane was oxidized by simultaneous addition of 30% H 2 O 2 (248 ml) and 3M NaOH (248 ml) solution. After the addition, the reaction mixture was heated at 50° C. for 3 hours. After completion of oxidation, the reaction mixture was diluted with water and extracted with ethyl acetate. The ethyl acetate layer was dried and concentrated. The crude product was purified by flash chromatography on silica gel using 10% ethyl acetate in pet. ether; m.p. 123° C., Yield: 52%.
EXAMPLE 7
Preparation of trans-(±)-1-[3-(2-Acetoxy)cyclohexyl-2,4,6-trimethoxy]phenyl-1-ethanone
Formula VII Wherein R 3 =4,6-dimethoxy, R 2 =CH 3 and R 4 =O--CO--CH 3
The product from Example 6 (1 eqvt.) was mixed with dry methylene chloride (1520 ml). Acetic anhydride (25 eqvt.) and phosphoric acid (152 ml) were added and stirred at room temperature for one hour. The reaction mixture was worked up by adding sodium carbonate solution until the reaction mixture was alkaline and extracted with dichloromethane. The organic layer was thoroughly washed with water and dried. The crude product after removal of the solvent was crystallized from pet. ether; m.p. 87° C., Yield: 84%.
EXAMPLE 8
Preparation of trans-(±)-1-[3-(2-Acetoxy)cyclohexyl-4,6-dimethoxy-2-hydroxy]phenyl-1-ethanone
Formula VII Wherein R 2 =H, R 3 =4,6-dimethoxy and R 4 =O--CO--CH 3
The product from Example 7 (1 eqvt.) was mixed with dry dichloromethane (5,450 ml) and cooled to 0° C. Borontribromide (1.1 eqvt.) was added with a syringe and stirred at 0° C. for one hour. Water was added carefully and the product was extracted with ethyl acetate, washed with water, and dried over anhydrous sodium sulfate. The crude product was crystallized from ethyl acetate; m.p. 151° C., yield: 70-71%.
EXAMPLE 9
Preparation of trans--(±)-2-[3-Acetyl-4,6-dimethoxy-2-hydroxy]phenylcyclohexanol
Formula VII Wherein R 2 =H, R 3 =4,6-dimethoxy, and R 4 =OH
The product from Example 8 (1 eqvt.) was stirred under nitrogen atmosphere with methanolic potassium hydroxide solution (20 eqvt., MeOH:water:3:1) for six hours. The reaction mixture was acidified with dil. HCl and the precipitate was filtered off, washed, dried and crystallized from ethylacetate; m.p. 161° C., Yield: 88-89%.
EXAMPLE 10
Preparation of trans-(±)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(4-chlorophenyl)prop-2-(E)-enoyl)]phenylcyclohexanol
Formula II Wherein R 1 =4-chlorophenyl, a=Another Bond, R 2 =H, R 3 =4,6-dimethoxy and R 4 =OH
The product from Example 9 (1 eqvt.) was stirred with 4-chlorobenzaldehyde (3 eqvt.) and 10% alcoholic sodium hydroxide (30 eqvt.) at room temperature for 24 hours. The reaction mixture was acidified with the dil. HCl at 0° C. to pH 5 and the orange precipitate was collected by filtration. Recrystallized from ethyl alcohol; m.p. 221° C., yield: 60%.
EXAMPLE 11
Preparation of trans-(±)-2-(4,6-Dimethoxy-2-hydroxy-3-(3-(4-chlorophenyl)propanoyl)]phenylcyclohexanol
Formula II Wherein R 1 =4-chlorophenyl, a=No Bond, R 2 =H, R 3 =4,6-dimethoxy and R 4 =OH
The product from Example 10 was stirred with 10% pd/c (5 mol %) in ethyl alcohol and under hydrogen overnight. The catalyst was filtered off and the solvent concentrated to give the product; m.p. 190° C., Yield: 90%.
EXAMPLE 12
An Alternative Preparation of trans-(±)-2-[2,4,6-trimethoxy)phenylcyclohexanol
Formula VI Wherein R 2 =CH 3 , R 3 =4,6-dimethoxy and R 4 =OH
2,4,6-Trimethoxybenzene (1 eqvt.), cyclohexene oxide (1.5 eqvt.) and dry dichloromethane (840 ml) were placed in a 3-necked r.b flask equipped with a stirrer. The reaction mixture was cooled to -78° C. and aluminum chloride (1.5 eqvt.) was added in small portions over a period of one hour. The stirring was continued for an additional period of three hours. The reaction mixture was worked up by addition of water and extracted with ethyl acetate. The crude product was crystallized from petroleum ether; m.p. 123° C., Yield: 63-64%.
EXAMPLE 13
Resolution of (±)-trans-2-(2,4,6-trimethoxy)phenylcyclohexanol
A Compound of Formula VI Wherein R 2 =H, R 3 =4,6-dimethoxy and R 4 =OH
(±) trans-2-(2,4,6-Trimethoxy)phenylcyclohexanol (50.0 g; 0.18797 mol), 3-nitrophthalic anhydride (26.399 g; 0.18797 mol) and pyridine (42.18 ml; 2.78×0.18797 mol) were heated at 100° under N 2 atmosphere for three hours. The reaction mixture was cooled to 0° C., neutralized with 2N HCl and the product obtained extracted with chloroform. The residue after evaporation of solvent was crystallized from methanol (400 ml) to give the crystals of compound of the formula VI, wherein R 4 is 3-nitrophthalyloxy (59.0 g; m.p. 198-200°). The hemi acid (0.1285 mol) was treated with (+) cinchonine (37.85 g; 0.1285 mol) in methanol (250 ml) on a steam bath for 30 minutes. Solvent was removed at reduced pressure and the residual salt [96.5 g, OR (+) 84.75° (Hg, 578)] crystallized from ethyl acetate pet. ether (1:1 1400 ml) to afford the crystals (45.0 g; OR (+) 75.11° (Hg 578) and a mother liquor [50.0 g; OR (+) 97.30° (Hg, 579)].
The crystals (45.0 g) on further crystallizations (thrice) from ethyl acetate-pet. ether afforded enriched cinchonine salt [31.0 g, OR (+) 71.08° (Hg, 578)]. The enriched salt on treatment with 2N HCl at 0° gave the resolved (-) compound of the formula VI, wherein R 4 is 3-nitrophthalyloxy [16.1 g; OR (-) 37.15° (Hg, 578). The hemi acid on hydrolysis with 7.5% KOH solution in methanol-water (1:2, 5878 ml) at reflux temperature, followed by crystallization of the product from ethyl acetate-pet. ether (24:160 ml) yielded (-)-trans-2-(2,4,6-trimethoxy)phenylcyclo-hexanol [7.0 g; OR (-) 43.430 (Hg, 578)].
The mother liquor (50.0 g) was treated with 2N HCl at 0° and the product was subjected to crystallizations (thrice) from ethyl acetate-pet. ether to give the crystals of the resolved (+) compound of formula VI; wherein R 4 is 3-nitrophthalyloxy [15.1 g; OR (+) 35.65° (Hg, 578)]. The hemi acid on hydrolysis with 7.5% KOH solution in methanol-water (1:2; 548.5 ml) at reflux temperature for 60 hours followed by crystallization of the product from ethyl acetate-pet. ether (25:150 ml) yielded (+) trans-2-(2,4,6-trimethoxy)phenylcyclohexanol [7.24 g; OR (+) 42.30° (Hg, 578)].
EXAMPLE 14
Preparation of trans-(+/-)-2-[4,6-dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl]phenylcyclohexanol
The product from Example 9 (1 eqvt.) was stirred with 3-bromobenzaldehyde (3 eqvt.) and 10% sodium hydroxide solution (10 eqvt. in 1:1 ethanol-water) at room temperature for 4 hours. The reaction mixture was diluted with ice-cold water and filtered. The orange residue on chromatographic purification over silica-gel furnished the title compound; m.p. 172-74° C., yield: 64%.
EXAMPLE 15
Preparation of trans-(+/-)-[4,6-dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-(S)-carb-tertbutoxyamino propanoate
The product from Example 14 (1 eqvt.) was stirred with 2-(S)-carb-tert-butoxyamino propanoic acid (1.5 eqvt.) and 4-dimethylaminopyridine (0.2 eqvt.) in dichloromethane (2,174 ml). Dicyclohexylcarbodiimide (1.5 eqvt.) in dichloromethane (1,176 ml) was added slowly using an addition funnel at room temperature and stirred for 1 hour. Dichloromethane was removed at a rotary evaporator and the residue crystallized from ethanol (1,450 ml) to afford the title compound was stirred with ether. The precipitated dicyclohexyl urea was filtered out. The filtrate was concentrated and the residue was chromatographed over silica-gel. The fractions enriched with less polar (tlc) diasteriomer were concentrated and the residue stirred with ethyl acetate-pet. ether (5,882 ml; 1:10) to afford the title compound; m.p. 139-44° C., yield: 30%. [HPLC: column-μ-porosil, detection--247 nm, flow rate--1.5 ml/min., mobile phase--hexane:ethyl acetate (80:20), assay--94.6%, retention time--13.7 min.].
EXAMPLE 16
Preparation of trans-(-)-2-[4,6-dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)phenyl]cyclohexyl-2-(S)-amino propanoate hydrochloride
The product from Example 15 (1 eqvt.) was stirred with anisole (6 eqvt.) at 0° C. Cold formic acid (200 eqvt.) was added slowly through an addition funnel and stirred at that temperature for 10 minutes. The temperature was then raised slowly (over 1.5 hours) to 20° C. and stirred at that temperature for 2 hours. Formic acid was removed completely in-vacuo (bath temperature 22° C.). The residue was stirred with dichloromethane (5,550 ml) at 0° C. and charged with etherial HCl (5,550 ml). The reaction mixture was stirred for 25-30 minutes and the solvents were removed at vacuum (bath temperature 22° C.). The oily residue was dissolved in dichloromethane (925 ml) and slowly charged with hexane (4,625 ml) while stirring. The supernant was decanted off and the gummy residue was again dissolved in dichloromethane (925 ml) and charged with hexane (4,625 ml) while stirring. The supernant was decanted off and the powdery residue was dried at high vacuum; m.p. 138-40° C., yield: 88% [HPLC: column--C18 nucleosil, detection--220 nm, flow rate--1.5 ml/min., mobile phase--water:acetonitrile:triethyl amine (40:60:0.1%) pH adjusted to 3.0 with orthophosphoric acid, assay--99.95%, retention time--5.43 min.]
The following is a sequence for the synthesis of Compound No. 9 of Table 2 and a description of the synthesis procedure therefor. ##STR17##
Synthesis Procedure for Compound No. 9 of Table 2
1. trans-(+/-)-2-(2,4,6-Trimethoxyphenyl)cyclohexanol (II)
Cyclohexene oxide (90.2 ml; 0.89 mol) was added dropwise to a mechanically stirred mixture of trimethoxybenzene (I, 100 g; 0.594 mol) and aluminum chloride (118.82 g; 0.89 mol) in dichloromethane (500 ml) cooled at -78° C. The addition was done over a period of 50 min. The reaction mixture was allowed to stir at that temperature and the progress of the reaction monitored by TLC (tlc system 25% ethyl acetate-pet ether; anisaldehyde spray; pdt. Rf-value 0.35). The reaction mixture was worked up after 3 hours by adding cold-water (400 ml) and extracting with ethyl acetate (4×400 ml). The combined organic layers were washed with water, brine, and dried over sodium sulphate. The solvents were removed in-vacuo at a rotary evaporator. The oily residue was crystallized from pet ether (400 ml) to get the crystals of the title compound (62 g). The mother liquor, on evaporation of the solvents followed by chromatography over silica gel (column diam. 9.5 cm; silica gel 800 g; eluent 10, 25 and 40% ethyl acetate-pet ether), gave 28 g of the title compound. In total, 90 g (yield 57%; mp. 125-27° C.) of the title compound was isolated.
2. trans-(+/-)-2-(3-Acetyl-2,4,6-trimethoxyphenyl)cyclohexyl acetate (III)
Acetic anhydride (660 ml; 6.975 mol) was added to the solution of the trans-(+/-)-2-(2,4,6-trimethoxyphenyl)cyclohexanol (II; 60 g; 0.225 mol) in dichloromethane (300 ml) at room temperature, while stirring. It was followed by the dropwise addition of orthophosphoric acid (85%; 40 ml; 0.347 mol) over 45 min. Reaction progress was monitored by TLC (tlc system 30% ethyl acetate-pet ether; spray reagent--anisaldehyde; product Rf--value=0.5). TLC of the reaction mixture after 15 min. revealed complete consumption of the starting material. The reaction mixture was then diluted with 250 ml of cold water, neutralized with solid sodium bicarbonate and extracted with dichloromethane (3×500 ml). The combined organic layer was washed with bicarbonate solution, water, brine and dried over sodium sulphate. It was then concentrated in-vacuo and the residue chromatographed over silica gel (column diam. 9.0 cm; silica gel--1 kg; eluent--5% and 10% ethyl acetate-pet ether) to get the title compound (64 gm; yield 81%; m.p. 82-85° C.).
3. trans-2-(3-Acetyl-4,6-dimethoxy-2-hydroxyphenyl)cyclohoxyl acetate (IV)
Boron tribromide (16.3 ml; 0.176 mol) dissolved in 250 ml of dichloromethane was added slowly to the solution of the trans-2-(3-acetyl-2,4,6-trimethoxyphenyl)cyclohexyl acetate (III; 56 g; 0.160 mol) in dichloromethane (350 ml) at 0° C. over 30 min. The reaction progress was monitored by TLC (tlc system 5% ethyl acetate-pet ether; anisaldehyde spray; pdt. Rf value--0.6); TLC of the reaction mixture after 15 min. indicated complete consumption of the starting material. The reaction mixture was then diluted with 250 ml of water and poured into saturated bicarbonate solution and extracted with dichloromethane (3×500 ml). The combined organic layer was washed with bicarbonate, water, brine, and dried over sodium sulphate. Solvents were removed at the rotary evaporator and the residue triturated with ethyl acetate-pet ether (100 ml; 1:1). The solid was filtered at suction and dried at high vacuum to get 34 g of the title compound. The mother liquor was chromatographed over silica gel (column diam. 5 cm; silica gel 150 g; eluent 10% ethyl acetate-pet ether) to get 9 g of the title compound. The total amount of the title compound isolated was 43 g (yield 80%; mp. 155-57° C.).
4. trans-2-(3-Acetyl-4,6-dimethoxy-2-hydroxyphenyl)cyclohexanol (V)
To a suspension of trans-2-(3-acetyl-4,6,-dimethoxy-2-hydroxyphenyl)cyclohexyl acetate (IV; 43 g; 0.128 mol) in methanol (460 ml) was added a solution of sodium hydroxide (20%; 154 ml) using the addition funnel and allowed to stir at room temperature for 15 min. The reaction mixture was then heated to 60° C. and the progress of the reaction monitored by TLC (tlc system 10% ethyl acetate-chloroform; anisaldehyde spray; pdt. Rf value 0.3). Complete consumption of the starting material was seen after stirring at 60° C. for 3 hours. The reaction mixture was then cooled in an ice bath and neutralized with 2N HCl. The precipitated solid was filtered and dried at high vacuum (dry solid 32 g). The filtrate was concentrated in-vacuo to remove methanol and extracted with ethyl acetate. The ethyl acetate layer was washed with water, brine and dried over sodium sulphate. It was concentrated and chromatographed over silica gel (eluent 3% ethyl acetate-chloroform) to get 3 g of the title compound. In total, 35 g of the title compound was isolated (yield 93%; mp. 162-64° C.).
5. trans(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)]phenyl cyclohexanol (VI)
A cold solution of sodium hydroxide (20%; 500 ml) was added slowly using the addition funnel to a solution of trans-2-(3-acetyl-4,6-dimethoxy-2-hydroxyphenyl)cyclohexanol (V; 72 g; 0.244 mol) and 3-bromobenzaldehyde (85.34 ml; 0.732 mol) in 500 ml of ethanol at room temperature and progress of the reaction monitored by TLC (tlc system 10% ethyl acetate-chloroform; UV detection). TLC of the reaction mixture after 4 hours revealed complete consumption of the starting material. The reaction mixture was diluted with ice-cold water (1000 ml) and the precipitated solid was filtered out. The residue after chromatography over silica gel (column diam. 9.5 cm; silica gel 1.5 Kg; eluent chloroform and 2% ethyl acetate-chloroform) furnished 21 g of the title compound. The filtrate on extraction with ethyl acetate followed by concentration and chromatography of the residue over silica gel (column diam. 5.5 cm; silica gel 400 g; eluent 50% chloroform-pet ether; chloroform and 2% ethyl acetate-chloroform) gave 4 g of the title compound. In total, 25 g of the title compound was isolated (yield 63.72%; mp. 172-74° C.).
6. trans(+/-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-(E)-enoyl)-phenyl]cyclohexyl-2-(S)-carb-tertbutoxyamino propanoate (VII)
To the stirred mixture of trans(+/-)-2-[4,6-dimethoxy-2-hydroxy-3-(3-bromophenyl)prop-2-enoyl)]phenyl cyclohexanol (VI; 85 g; 0.184 mol), 2-(S)-carb-tert-butoxyamino propanoic acid (52.22 g; 0.276 mol), and dimethylaminopyridine (4.25 g; 5% by weight of VII) in dichloromethane (400 ml) was slowly added a solution of dicyclohexyl carbodiimide (57 g; 0.276 mol) in dichloromethane (220 ml) using an addition funnel at room temperature. Reaction progress was monitored by TLC (tlc system 40% ethyl acetate-pet ether or 20% ethyl acetate, 20% chloroform-pet ether; UV detection; pdt. Rf value 0.8). TLC of the reaction mixture after 1 hour revealed complete consumption of the starting material. Dichloromethane was removed at the rotary evaporator and the residue stirred with ether. The precipitated dicyclohexylurea was filtered out. The filtrate was concentrated at the rotary evaporator and the residue chromatographed over silica gel (column diameter 10.5 cm; silica gel 1 Kg; eluent 5% and 10% ethyl acetate-pet ether). The fractions enriched with less polar diasteriomer (tlc) were mixed together and concentrated. The residue was stirred with ethyl acetate-pet ether (1300 ml/1:12) and the precipitated solid was filtered out. This solid was again stirred with ethyl acetate-pet ether (1100 ml; 1:10) and filtered to give 34.5 g of the pure title compound (HPLC) as a yellow orange solid (yield 30%).
7. trans(-)-2-[4,6-Dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-enoyl)-phenyl]cyclohexyl-2-(S)-aminopropanoate hydrochloride (VIII)
A cold formic acid (408 ml; 10.8 mol) was added slowly through the addition funnel to the precooled (0° C.) suspension of trans(-)-2-[4,6-dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-enoyl)phenyl]cyclohexyl-2-(S)-carb-tert-butoxyamino propanoate (34 g; 0.054 ml) in anisole (34 ml; 0.313 mol), over a period of 15 min. The reaction mixture was stirred at that temperature for 10 min. Then the temperature was allowed to rise slowly (over 1.5 hours) to 20° C. and stirred at that temperature for 2 hours. TLC (tlc system 10% methanol-chloroform; UV detection; pdt. Rf value 0.6) of the reaction mixture showed complete consumption of the starting material. Formic acid was removed completely in-vacuo (bath temperature 22° C.). The residue was stirred with toluene and the toluene stripped off in-vacuo (bath temperature 22° C.) to remove the traces of formic acid. The residue, i.e., trans-2-[4,6-dimethoxy-2-hydroxy-3-(3-(3-bromophenyl)prop-2-enoyl)phenyl]cyclohexyl-2-(S)-aminopropanoate formate salt, was immediately subjected to the hydrochloride formation as follows.
Etherial HCl (300 ml) was added slowly using an addition funnel to the precooled (0° C.) solution of the formate salt in dichloromethane (300 ml) and stirred at that temp. for 25-30 min. Solvents were removed in-vacuo (bath temperature 20-22° C.). The oily residue was then dissolved in dichloromethane (50 ml) and slowly charged with hexane (250 ml), whilst stirring. The stirring was then stopped and the reaction mixture allowed to settle. The supernatant was decanted off. The gummy residue was again stirred with 50 ml of dichloromethane and 300 ml of hexane. The supernatant was decanted off and the residue stirred thrice with hexane (300 ml each time). The supernatants were decanted off and the powdery residue was dried at high vacuum (bath temperature 50° C.) to get the title compound (27 g; yield 88%).
______________________________________HPLC details of Compound No. 9 of Table 2:______________________________________Retention time: 5.43 min.Detection: 220 nmAssay (purity): 99.95%Flow rate: 1.5 ml/min.Mobile phase: Water-acetonitrile-triethylamine; (40:60:0.1%) (pH adjusted to 3.0 with orthophosphoric acid)Column: C18, Nucleosil______________________________________
Pharmacological Profile of Compound No. 9 of Table 2
EXAMPLE 17
Effect on Adjuvant-Induced Arthritis in Rats
Adjuvant-induced arthritis in the rat is a model which permits the evaluation of the potential of a compound to inhibit an arthritic condition in rats which is similar to the human rheumatoid arthritis. This model differentiates between the immunomodulatory and anti-inflammatory potential of the compound. The potency of the test compound is statistically assessed by measuring the reduction in the volumes of both injected and uninjected hind paws in comparison with the control (untreated) group.
Method
Female Wistar rats (120-150 g) were randomly distributed in groups of 10 rats each, after receiving 0.1 ml of a 1% suspension of Mycobacterium tuberculi in paraffin oil intrapedally into one hind paw (injected paw). Contralateral hind paw (uninjected paw) developed secondary lesions in about 10 days time, which were due to the development of an immune reaction. Drug treatment was started on the day of induction of arthritis and continued for 12 days. Treatments included different doses of the test compound and the standard compound viz, cyclophosphamide. Paw volume measurements were done using a water plethysmometer on day one and thereafter for the period of 35-40 days. The volumes of both injected and uninjected hind paws were monitored in control (untreated) as well as treated groups. Compound 9 of Table 2 was administered at the doses of 1, 3, 10, 30 mg/kg orally once a day. The test compound showed significant and dose dependent reduction in the uninjected paw volumes at doses 3, 10, and 30 mg/kg; as shown in FIG. 2. This activity is to be contrasted with the activity for the representative compound, compound 6 of Table 1, which when fed orally at 30 mg/kg once every day for 12 days showed very slight reduction in the uninjected paw volume (FIG. 3) compared to control, demonstrating thereby the superiority of compound 9 of Table 2 in this activity.
EXAMPLE 18
Effect on Experimental Allergic Encephalomyelitis (EAE) in Guinea Pigs
This method permits the evaluation of the potential of the test compound in preventing the development of an autoimmune disorder leading to demyelination in the guinea pigs which can be equated to multiple sclerosis disease in humans. EAE is a reproducible chronic inflammatory autoimmune disease of the central nervous system in which an animal is immunized with either a homologous or heterologous extract of the whole brain and spinal cord, which contains the basic myelin protein together with Freund's Complete Adjuvant (FCA). A pathological condition would set in during ten to twenty days following immunization, which is characterized by weight loss, abnormal gait, mild to severe ataxia, paraparesis and moribund state leading to death. The potential of the test compounds to prevent this autoimmune condition was evaluated by observing the severity of the disease and mortality in comparison with untreated and hydrocortisone (standard drug) treated animals.
Method
Guinea pigs (200-300 g) were randomly distributed into groups of 10 each after receiving 0.075 ml of it brain and spinal cord extract in FCA intradermally on the back and 0.050 ml intrapedally in one hind paw. Compound 9 of Table 2 was administered orally at 3 mg/kg once daily for 10 days. The standard compound was administered 100 mg/kg p.o. once daily for 10 days. The weights of the animals were noted every day. Eight days after the induction of the disease, the animals were rated regularly for the severity of the disease and mortality was monitored. The test compound reduced the mortality rate by 45% while hydrocortisone produced only 21% reduction in the mortality as shown in FIG. 4. Also the clinical symptoms were significantly reduced in the test compound treated group as compared to the untreated group as shown in FIG. 5.
EXAMPLE 19
Oral bioavailability in the Rat and Dog
Since the test compound produced significant activity in the adjuvant arthritic rats and experimental allergic encephalomyelitic guinea pigs when administered orally, the extent of oral bioavailability of this compound was estimated in rats and dogs. Compound 9 of Table 2 was administered intravenously (1 mg/kg) to conscious rats and dogs and blood samples were collected at various time points after administration. Similarly, the test compound was also administered orally (10 mg/kg) to a different set of rats and dogs and blood samples were collected at various time points. The blood samples were extracted and were analyzed by HPLC to obtain the concentration of compound 9 in the plasma. The plasma levels obtained after intravenous and oral administration were plotted against time, areas under the curves were calculated and percent bioavailability were estimated. The test compound showed 46% oral bioavailability in the rat and 73% oral bioavailability in dog as shown in Table 6. The extent of oral bioavailability in different species clearly indicates that compound 9 of Table 2, a representative example of the compounds of the present invention can be administered orally as a therapeutic agent.
TABLE 6______________________________________ Dose mg/kg %Species (Oral) Bioavailability______________________________________Rat 10 46Dog 10 73______________________________________ | Compounds of formula I, ##STR1## and the physiologically tolerable salts thereof, wherein the substituents R 1 -R 4 have the meanings given in the specifications and show an activity against inflammatory conditions. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image forming apparatus such as a copier, printer, and the like using an electrophotographic system or a static recording system.
2. Related Background Art
In the image forming apparatus using an electrophotographic system, for example, a static latent image is formed on a surface of a photosensitive drum or a photosensitive belt, which is an image bearer, and the static image on the image bearer is developed by a developer, such as toner, to visualize an image as a toner image. The developed image is transferred to a transferring material by a transferring apparatus, to cause the toner image to be borne by the transferring material, and the toner image is fixed to the transferring material by heating and pressing by a fixing apparatus. By sequentially carrying out these steps, the image is formed.
Meanwhile, toner is consumed as the image forming apparatus is used and hence, a user should supply toner. Known methods for supplying toner include charging only toner in the image forming apparatus, replacing the developing apparatus including a toner container, or replacing a unit including the photosensitive drum.
There are methods for detecting of the amount of unused toner to inform the user of the time to replace toner. Conventional methods for residual toner detection are as follows.
In developing the static latent image formed on the image bearer by powder toner, toner is adsorbed and transferred by a static force. Toner is previously magnetized and then an electrostatic force is applied to the developing roller in the developing apparatus caused by a voltage difference to cause the toner to be adsorbed to the surface of the developing roller. The developing roller is disposed opposite to the image bearer and an electrostatic force stronger than that of the developing roller is applied to the image bearer. Then, toner is transferred and adsorbed from the developing roller to the image bearer and the latent image on the image bearer is visualized by toner.
Thus, the method for detecting a residual toner amount employs the voltage to be applied to the developing roller. Voltage is applied to the developing roller in order to adsorb and transfer toner as described above and the voltage and the electrostatic force are effective to all radial directions of the developing roller. For example, when an antenna, which is made of a conductive material is disposed in a position distant from the developing roller, an electric charge is generated in the antenna side by an electric potential difference. Hence, if toner which is a dielectric material exists between the developing roller and the antenna, the electric charge changes compared with absence of toner. As the amount of toner differs, the magnitude of the electric charge also differs and thus, the residual amount of toner can be detected by measuring the electric potential according to the electric charge to know relative comparison with the amount of toner.
However, there are problems in the conventional residual toner detection method as follows.
As shown in FIG. 4, the antenna 30 for measurement of the electric charge is disposed in the toner container 31 and thus, disturbs replacement of the toner container 31 (or, the developing apparatus or a process cartridge) for toner supply. In FIG. 4, a reference numeral 6 denotes a drum unit having a photosensitive drum 1 .
In addition, as shown in FIG. 5, a contact 34 of antenna side in the toner container 31 should be attached to and detached from a contact 35 of main body side of the image forming apparatus. However, the conventional residual toner detection method is the detection method by measuring a micro voltage and therefore, a low reliability of the contact point does not allow for detection of a correct residual toner amount. Particularly, in a color image forming apparatus, as shown in FIG. 6, having a plurality of developing apparatus 4 BK, 4 Y, 4 M, and 4 C, antennas 30 BK, 30 Y, 30 M, and 30 C are disposed in developing apparatus 4 BK, 4 Y, 4 M, and 4 C, respectively, and hence, the increased number of the contact points results in lower reliability of the image forming apparatus and also a plurality of 30 BK, 30 Y, 30 M, and 30 C are necessary and hence, the cost increases. For information, in FIG. 6, the reference numeral 6 denotes a photosensitive drum unit having a photosensitive drum 1 .
SUMMARY OF THE INVENTION
An object of the present invention is to provide an image forming apparatus of high reliability of the contact point for detecting an amount of the developer.
Another object of the present invention is to provide an image forming apparatus comprising: an image bearer for bearing a static image; an exchangeable type developing for developer the static image on the image bearer, the developing apparatus comprising, a developing chamber having a developing roller in an opening opposite to the image bearer, and a containing chamber for containing a developer to be supplied to the developing chamber; a detection electrode disposed outside the developing apparatus and in which a voltage is induced; and detection means for detecting an amount of the developer in the containing chamber on the basis of an induced voltage of the detection electrode.
Further objects of the present invention will be apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of an image forming apparatus (a laser beam printer) according to the present invention;
FIG. 2 is a side view of a developing apparatus and a photosensitive drum unit of a monochromatic color image forming apparatus according to embodiment 1 of the present invention;
FIG. 3 is a side view of the developing unit and the photosensitive drum unit of a color image forming apparatus according to embodiment 2 of the present invention;
FIG. 4 is a side view of the developing apparatus and the photosensitive drum unit of the monochromatic color image forming apparatus;
FIG. 5 is a front view of the developing apparatus of the monochromatic color image forming apparatus; and
FIG. 6 is a side view of the developing unit and the photosensitive drum unit of the color image forming apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will be described below with reference to the drawings attached herewith.
FIG. 1 is the sectional view of the laser beam printer as an embodiment of the image forming apparatus, according to the present invention using electrophotography and the laser beam printer can form a tetrachromatic full-color image.
The image forming apparatus A, which forms image by fixing an image visualized by the developing to the transfer material by heating, comprises a photosensitive drum 1 which is an electrophotographic photosensitive member of a drum type as a first image bearer. The photosensitive drum 1 is incorporated into the photosensitive drum unit 6 and rotatively driven by driving means, not illustrated, in a direction (counterclockwise) of an arrow illustrated.
Around the above-described photosensitive drum 1 , sequentially in a rotational direction of the photosensitive drum 1 , a charging apparatus 2 for charging evenly a surface of the photosensitive drum 1 , an exposing apparatus for forming a static latent image on the photosensitive drum 1 by radiating a laser beam based on an image information, the developing unit 4 for developing the latent image as a toner image by attaching toner to the latent image on the photosensitive drum 1 , an intermediate transfer unit 5 as a second image bearer on which the toner image on the photosensitive drum 1 is primarily transferred, and the like are disposed.
The developing unit 4 for developing the static latent on the photosensitive drum 1 has four developing apparatus, i.e., 4 BK, 4 Y, 4 M, and 4 C, containing four color toners and these developing apparatus, 4 BK, 4 Y, 4 M, and 4 C, are disposed concentrically around a rotating shaft 4 a . In respective developing apparatus, 4 BK, 4 Y, 4 M, and 4 C, the developing rollers 4 b are respectively disposed to bear toner, which is the developer, on the surface thereof and to be positioned opposite to the photosensitive drum 1 when the developing apparatus, 4 BK, 4 Y, 4 M, and 4 C, are faced to the photosensitive drum 1 . The static latent image on the photosensitive drum 1 is developed by the developing roller 4 b to be visualized as the toner image.
The above-described intermediate transfer unit 5 as a second image bearer primarily transfers the toner image on the photosensitive drum 1 and then, secondarily transfers the toner image to the surface of the transferring material S fed to the intermediate transfer unit 5 . The transferring material S is carried from a cassette 14 to the intermediate transfer unit 5 by carrying means in predetermined timing.
In the image forming apparatus A, the fixing apparatus 8 is disposed to fix the toner image to the transferring material S by heating toner on the transferring material S after secondary transfer. The transferring material S passed through the fixing apparatus 8 is discharged to a sheet discharging tray 10 by a carrying unit 9 . The fixing apparatus 8 has a fixing roller 8 a and a pressing roller 8 b , which are a pair of rolling bodies, and by passing the transferring material S bearing the toner image between the fixing roller 8 a and the pressing roller 8 b with the surface of the fixing roller 8 a heated to a predetermined temperature by a heater (not illustrated) in the fixing roller 8 a , heats and presses the transferring material S to fix the toner image to the transferring material S. The heater may be disposed inside the pressing roller 8 b.
In this embodiment, the static latent image is developed by electrostatic adsorption of toner to the photosensitive drum 1 . In case of a monochromatic color image forming apparatus, there is single developing apparatus, the intermediate transfer unit is not necessary, and the toner image is directly transferred from photosensitive drum bearing a developed image to the transferring material.
<Embodiment 1>
Embodiment 1 according to the present invention will be described with reference to FIG. 2 . FIG. 2 is a side view of a developing apparatus and a photosensitive drum unit of a monochromatic color image forming apparatus.
The photosensitive drum unit 6 shown in FIG. 2 has the photosensitive drum 1 as an image bearer and in developing the static latent image formed on the photosensitive drum 1 , unused toner 22 contained in the toner container 21 of the developing unit 4 is rotatively carried to the developing roller 4 b by the carrying roller 4 d to make toner 22 to be electrostatically adsorbed to the surface of the developing roller 4 b by applying voltage to the developing roller 4 b . And, to the photosensitive drum 1 opposed to the developing roller 4 b , the voltage is applied to generate an adsorbing force larger than the electrostatic adsorbing force of the developing roller 4 b . As a result, by a bias formed by the photosensitive drum 1 and the developing roller 4 b , toner on the developing roller 4 b is transferred to the photosensitive drum 1 .
Now, the detection method for the residual toner amount will be described below.
By the voltage applied to the developing roller 4 b , the antenna 20 disposed previously in the main body of the image forming apparatus is electrically charged to cause an electric current to flow to the main body. Between the developing roller 4 b and the antenna 20 , unused toner 22 is interposed and unused toner 22 becomes a dielectric material and hence, according to the change of residual amount of the unused toner 22 , electric charge on the antenna 20 changes to change the electric current and voltage. Consequently; on the basis of the change of the electric current and voltage, the residual amount of the unused toner 22 can be detected. The antenna 20 comprises a linear or plate-like metal.
Therefore, according to the present invention, by disposing the antenna 20 in the main body side of the image forming apparatus, the contact point becomes unnecessary, which allows the developing apparatus to be attached and detached for toner replacement between the antenna 20 and the image forming apparatus and hence, reliability and detection precision of the contact point of a detection current are increased in detecting the residual toner amount.
<Embodiment 2>
Next, The embodiment 2 according to the present invention will be described with reference to FIG. 3 . FIG. 3 is a side view of the developing unit and the photosensitive drum unit of the color image forming apparatus.
In FIG. 3, reference numerals 4 and 6 denote the developing unit having a plurality of developing apparatus 4 BK, 4 Y, 4 M, and 4 C and the photosensitive drum unit having the photosensitive drum 1 , respectively. Development of the static latent image on the photosensitive drum 1 in the color image forming apparatus having the developing unit 4 and photosensitive drum unit 6 is similar to the monochromatic color image forming apparatus according to the above-described embodiment 1.
For example, in the case where development is carried out by using the developing apparatus 4 Y of a yellow color, unused toner 22 Y contained in the toner container 21 Y is rotatively carried to the developing roller 4 b Y by the carrying roller 4 d Y. And then, the voltage is applied to the developing roller 4 b Y to cause toner 22 Y to be statically adsorbed to the surface of the developing roller 4 b Y. To the photosensitive drum 1 opposite to the developing roller 4 b Y, the voltage is applied to generate the adsorbing force larger than static adsorption force of the developing roller 4 b Y in order to transfer toner 22 Y on the developing roller 4 b Y to the photosensitive drum 1 by the bias formed by the photosensitive drum 1 and the developing roller 4 b Y. In the developing apparatus 4 M, 4 C, and 4 BK of magenta, cyan and black colors, respectively, the same development as above-described is carried out and in the toner containers 21 M, 21 C, and 21 BK, 22 M, 22 C, and 22 BK are disposed, respectively.
Subsequently, the method for detection of residual toner amount will be described below.
By the voltages applied to respective developing rollers 4 b Y, 4 b M, 4 b C, and 4 b BK, the antenna 24 , disposed in the main body of the image forming apparatus, is electrically charged to make the electric current flow to the main body. Between the respective developing rollers 4 b Y, 4 b M, 4 b C, and 4 b BK and the antenna 24 , unused toners 22 Y, 22 M, 22 C, and 22 BK are interposed and these kinds of unused toners 22 Y, 22 M, 22 C, and 22 BK become dielectric and hence, according to the change of the residual amount of toner, the electric charge on the antenna 24 changes to change the electric current and voltage. Consequently, on the basis of the change of the electric current and voltage, the residual toner amount of the unused toners 22 Y, 22 M, 22 C, and 22 BK can be detected.
Therefore, in the case of this color image forming apparatus where selection and switching of a plurality of the developing apparatus, 4 Y, 4 M, 4 C, and 4 BK is performed by a rotational mechanism, by disposing the antenna 24 in a center 4 f of the rotating shaft 4 a , the contact point becomes unnecessary which allows the developing apparatus 4 Y, 4 M, 4 C, and 4 BK to be attached and detached for toner replacement, between the antenna 24 and the image forming apparatus and hence, as with the above described embodiment 1 reliability and detection precision of the contact point of detection current are increased in detecting the residual toner amount.
In addition, installing the single antenna 24 in the center 4 f of the rotating shaft 4 a simply allows for detection of residual toner in the plurality of developing apparatuses and hence reduction of a number of the antenna.
The embodiments above described should be considered in all respects as illustrative and not restrictive; any modification can be made within the technical concept. | An image forming apparatus includes an image bearer bearing a static image and an exchangeable type developing apparatus for developing the static image on the image bearer. The developing apparatus includes a developing chamber having a developing roller in an opening opposite to the image bearer, and a containing chamber containing a developer to be supplied to the developing chamber. A detection electrode is disposed outside the developing device and in which a voltage is induced. A detection device detects an amount of the developer in the containing chamber on the basis of an induced voltage in the detection electrode. | 6 |
REFERENCE TO RELATED APPLICATION
[0001] This application is a Continuation of U.S. Non-Provisional patent application Ser. No. 12/932,892, filed Mar. 8, 2011, which is a Continuation-in-Part of U.S. Non-Provisional patent application Ser. No. 12/572,176, filed Oct. 1, 2009, which is a Non-Provisional of U.S. Provisional Patent Application. No. 61/102,333, filed Oct. 2, 2008, the complete disclosures of which are incorporated herein, in their entireties.
[0002] 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 by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent files and records, but otherwise reserves all other copyright rights.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The field of the invention is skylights systems.
[0005] 2. Description of Related Art
[0006] Various systems are known for using curb construction for inserting skylights and smoke vents into roofs.
[0007] The most commonly used skylighting systems are those that incorporate translucent or transparent layers in a framework that penetrates the roof structure, so as to allow ambient daylight into the building.
[0008] In the past roof penetrating installations have required a complex structure beneath the roofing panels in order to support a roof curb to which the skylight was attached. Skylight curbs are generally in the form of a preassembled box structure, that is fixed within a roof cutout, The retrofitting of such curb systems into existing roof structure is problematic.
[0009] U.S. Pat. No. 4,296,581, to Heckelsberg, issued Oct. 27, 1981, provides an example of a roofing structure of the type that is constructed of a series of metal panels having flanges that interlock when the panels are laid side by side and which are subsequently tightly seamed together to convert the individual panels into an integrated roof forming membrane. This roof structure is mounted to the purlins with clips that permit the panels to expand or contract in response to temperature and pressure changes, thereby minimizing roof stressing.
[0010] U.S. Pat. No. 4,703,596, to Sandow, issued Nov. 3, 1987, and titled “Grid Skylight System”, provides a grid skylight support apparatus that includes prefabricated grid row frames, each of which form a number of connected beam supports which define a number of bays. Each bay has a skylight curb formed by upper flanges of the beam supports to receive a preassembled skylight unit. The sides of each grid row frame provide a mating edge that can register with the mating edge of an adjacent grid row frame during assembly. The skylights have peripheral support skirts that register upon each bay and a light-transmitting skylight panel to cover the peripheral support. Cross gutters on each grid row frame, which are positioned between adjacent skylights, extend at an angle toward the mating edge of the grid row frame for carrying rainwater to a main gutter channel formed by field-assembly of the mating edges of two adjacent grid row frames. The main gutter channel includes a pair of longitudinally extending gutter sections, each of which have a main gutter channel surface with a lower elevation than the elevation of the cross flow channel. Fasteners assemble the grid row frame mating edges together and a continuous seal to prevent rainwater leakage at the mating edges of adjacent grid row frames.
[0011] U.S. Pat. No. 4,520,604, to Halsey et al., issued Jun. 4, 1985, entitled “Skylight Structure”, teaches a curb structure that is dimensioned to be passed through an opening in a roof and then attached in moisture impervious relation to the roof from within a building interior. A skylight assembly including a frame and light transmitting member secured to the frame is dimensioned to be passed through the opening and attached in a sealing engagement to the curb structure from within the building interior for covering the opening. The skylight assembly is then secured to the rafters and headers at an interior location. The frame includes upper and lower clamping jaws and spaced fulcrum links attached to the jaws for clamping the light transmitting member thereto. The lower clamping jaw includes a channel which engages and is interlocked with the curb structure.
[0012] Other skylight systems, as contemplated in U.S. Pat. No. 4,470,230, by Weinser, provide a prefabricated skylight support curb that is formed to be a protective packaging for the skylight during shipment and then used as a curb for mounting the skylight on a roof. A prefabricated skylight support curb for supporting a skylight thereover has a bottom flange angled, upright sides, and a top lip round the top of the sides forming an opening through the curb. A skylight is adapted to cover the opening through the skylight support curb when installed, and has a domed portion and an angled portion extending from the dome portion and a drip edge on the curb portion. The skylight curb portion is shaped to fit over a portion of the prefabricated skylight support curb angled upright portion and top lip. The skylight support curb is shaped to nest an accompanying skylight therein having the skylight curb portion adjacent to the interior of the skylight support curb angled upright walls to protect the skylight during shipping and storing.
[0013] In another skylight system, as contemplated in U.S. Pat. No. 3,791,088, by Sandow, at al., a prefabricated multiple dome unit or skylights and composite is provided, wherein each multiple dome unit has several domes of transparent or translucent material mounted together on a common frame, and wherein means are provided for assembling a plurality of such dome units into a composite thereof on a building, with the units lapped and interfitted so as to provide a continuous drainage system discharging to the exterior of the units in the composite assembly.
[0014] In yet another skylight system, as contemplated in U.S. Pat. No. 4,642,466, by Sanneborn, at al., a flashing frame is described for roof windows to be installed adjacent to each other with edges facing each other in the installed position with a connecting flange of its upper flashing members extending beneath the roofing and, if need be, with its lower flashing members and required intermediary flashing members, obliquely outwardly bent connecting webs and each with a connecting bar with supporting webs which rearwardly engage the connecting webs being adjacent to the width of the installation distance and are obliquely bent inwardly on both sides, and at least one inner projection which engages between the facing corner edges of the connecting webs in the installed position, thus maintaining these corner edges at the installation distance.
[0015] In today's world of mandated energy efficiency in all types of buildings the metal building industry needs a more economical and less detrimental way to use skylights and smoke vents to daylight their buildings. To ensure adequate daylighting, however, typical skylight and smoke vent installations require multiple roof penetrations that cut through and remove plural major elevations in standing seam and other roof panel profiles. These curbs create multiple opportunities for water to enter the interior of the building, due to multiple curb locations and the width of the curbs, as well as the challenge to effectively seal the roof at the high end of such curbs.
[0016] The traditional curb constructions and methods of attachment in most cases require a complicated support structure to be installed below the roof panel which can restrict movement associated with the thermal expansion and contraction of the metal roof due to temperature changes and the like.
[0017] None of the prior approaches have been able to provide an installation system for multiple skylights that accomplishes all the goals of economy and simplicity of installation and will work equally well for new buildings and as a retrofit in existing buildings.
SUMMARY OF THE INVENTION
[0018] The invention provides a curbless construction system for installing two or more adjacent skylights and smoke vents end to end onto the major rib elevation of a building's metal roof system panel. Numerous roof structures include such elevations, sometimes deemed “ribs” or “corrugations”, including the standing seam, snap seam and “R” panel roof types. The rail and closure system is fastened to the metal roof panels along the rib structures, so that the system can move with the expansion and contraction of the roof.
[0019] The invention utilizes elements of the roof surface structure as an integral part of the skylight support structure. In the preferred embodiment, the system includes a rail and closure assembly adapted to be supported on a major rib elevation a metal roof, typically where the elevation has been cut to accommodate drainage. The balance of the rib is to provide structural support for the rail assemblies.
[0020] Also in the preferred embodiment, the skylight/smoke vent system includes a skylight adapted to be supported on the rail and closure assembly, and a bearing plate structure for supporting and sealing the portion of the elevations that have been cut away preventing water accumulation at the surface, thus preventing water egress into the building.
[0021] In a further preferred embodiment, the invention provides a skylight system (including smoke vents) where the bearing plate structure cooperates with the rail and closure assembly to close the cut away portion to water egress.
[0022] In another preferred embodiment, the invention provides a skylight system where the metal roof is selected from the group of roofs comprising a standing seam roof, an architectural standing roof and a snap seam roof.
[0023] In another preferred embodiment, the invention provides a skylight system where the rib has been cut in only one location.
[0024] In a further preferred embodiment, the invention provides a skylight system where the standing seam roof has trapezoidial rib elevations.
[0025] In still further preferred embodiment, the invention provides a skylight system where the ribs are about 24″ to about 30″ on center.
[0026] In a different preferred embodiment, the invention provides a skylight system where the metal roof is selected from the group of roofs comprising an architectural standing roof and a snap seam roof, and where the vertical rib configurations are about 12″ to about 18″ on center.
[0027] In still further preferred embodiment, the invention provides a skylight system where the metal roof is an exposed fastener roof system.
[0028] In one preferred embodiment, the invention provides a skylight system where the rib has been cut in two locations.
[0029] In a different preferred embodiment, the invention provides a skylight system having a trapezoidial or rectangular rib elevation to 8″ to 12″ on center.
[0030] In another preferred embodiment, the invention provides a skylight system where the exposed fastener roof is of the type having roof panels fastened directly to the roof purlin from the top side of the roof panel.
[0031] In a further preferred embodiment, the invention provides a skylight system where the system comprises two or more skylights supported end to end.
[0032] In a different preferred embodiment, the invention provides a skylight system (including smoke vents) where each of the skylights are about 10 feet in length.
[0033] In one preferred embodiment, the invention provides a skylight system where the rail and closure assembly moves with the rib elevation.
[0034] In different preferred embodiment, the invention provides a skylight system further comprising a ridge cap configured to fit over the standing rib elevations at the ridge of the roof.
[0035] In a further preferred embodiment, the invention provides a skylight system where a lower closure of the skylight rail and closure assembly extends across the top of the metal roof panel profile.
[0036] In one preferred embodiment, the invention provides a skylight system where the closure is configured to match the roof panel surface adjacent rib elevations for sealing.
[0037] In a further preferred embodiment, the invention provides a skylight system where the closure is pre-cut to match the roof surface and adjacent rib elevations for sealing.
[0038] In a still further preferred embodiment, the invention provides a skylight system where the rail and closure assembly is fastened directly to the rib elevations using screws or rivets.
[0039] Where an extension is attached to the upper flange of the rail and closure assembly to effectively raise the height of the skylight or smoke vent to accommodate snow conditions and the like.
[0040] In a preferred embodiment the invention provides a skylight system further comprising a safety security guard attached to the rail assembly.
[0041] In a still further preferred embodiment, the invention provides a skylight system where the rail and closure assembly comprises an extended down leg on the inside of the roof cut away segment.
[0042] In another preferred embodiment, the invention provides a skylight system where the rail and closure assembly forms a water tight seal with the rib elevation.
[0043] In a preferred embodiment, the invention provides a skylight system where a side rail elevation attaches to the interior of the rib elevation.
[0044] In a further preferred embodiment, the invention provides a skylight system here the side rail elevation attaches to the anterior of the rib elevation.
[0045] In a different preferred embodiment, the invention provides a skylight system where a portion of the adjacent rib elevation is cut away to accommodate drainage along the roof surface.
[0046] In a still further preferred embodiment, the invention provides a skylight system where a portion at only one adjacent rib elevation is cut away to accommodate drainage along the roof surface.
[0047] In another preferred embodiment, the invention provides a skylight system where a portion at two or more adjacent rib elevations is cut away to accommodate drainage along the roof surface.
[0048] These and other features and advantages of this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the apparatus and methods according to this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0049] A more complete understanding of the present invention and the attendant features and advantages thereof may be had by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein various figures depict the components and composition of the multiple skylight system.
[0050] FIG. 1 is a view showing the roof profile of a metal roof of the type known as the standing seam roof panel.
[0051] FIG. 2 is a view showing the roof profile of a metal roof of the type known as an architectural standing seam roof.
[0052] FIG. 3 is a view showing the roof profile of a metal roof of the type commonly referred to as a snap seam roof.
[0053] FIG. 4 is a view showing the roof profile of a metal roof of the type commonly referred to as an exposed fastener roof panel.
[0054] FIG. 5 is a view showing the roof profile of metal roof of the type commonly known as foam core panel.
[0055] FIG. 6 is a side view showing the major components of the system as installed on a metal roof.
[0056] FIG. 7 is a top plan view of the installed system, showing the placement of skylights and the direction of water flow over the roof.
[0057] FIG. 8 is a cross sectional view showing the connections of the skylight frame to the rail and closures structure, and the latter affixed over the outer surfaces of adjacent rib elevations of the metal roof.
[0058] FIG. 9 is a cross sectional view showing an alternative arrangement for the elements shown in FIG. 8 , only with the rail and closure structure connecting along the inner faces of adjacent rib elevations.
[0059] FIG. 10 is a perspective view partially cut way showing internal structure of the system as installed on the rib elevations of a metal roof.
[0060] FIG. 11 is a perspective view of the upper rain pan or diverter of the rail and closure structure.
[0061] FIG. 12 is a top view of the upper rain pan or diverter of the rail and closure structure.
[0062] FIG. 13 is a front plan view of the upper rain pan or diverter of the rail and closure structure.
[0063] FIG. 14 is a perspective view of the lower rain pan or lower closure of the rail and closure structure.
[0064] FIG. 15 is a top view of the lower rain pan or lower closure of the rail and closure structure.
[0065] FIG. 16 is a front plan view of the lower rain pan or lower closure of the rail and closure structure.
[0066] FIG. 17 is a perspective and partially cut away view showing a connection of adjacent skylights of the system.
[0067] FIG. 18 shows detail of how the batten connects adjacent skylights and prevents water egress between them.
DETAILED DESCRIPTION OF THE INVENTION
[0068] The products and methods of the present invention provide a skylight rail and closure system for use in installing various roof penetrating structures in metal roofs. For purposes of simplicity, “roof penetrating structures” and “skylights” will be used interchangeably to mean various forms of roof structures installed for passage of light and/or ventilation to the interior of the building. In the case of roof ventilation, examples include simple ventilation openings, such as for roof fans, and smoke vents, which are used to allow the escape of smoke through the roof during fires.
[0069] The number of skylights can vary from one to many structures connecting end to end be from one to as many as the building roof structure will support, limited only by the amount of support provided by the roof surface structure, which is left largely intact during the installation process.
[0070] The system utilizes the major rib structure in the roof as the primary support structure and water barrier to fasten the skylight assembly. Typical skylight installations do not allow for continuous runs, but use a curb construction that is typically 2-3 times wider than the present system.
[0071] The present skylight system does not require a complex structure underneath the panels or a separate curb construction to support or attach the skylight. The rail and closure assembly is overlaid onto the roof system and allows for thermal expansion and contraction by utilizing the major profiles of the metal roof panel for support. This is accomplished through direct attachment of the rail assembly and a combination of the panel flat and major ribs for support and attachment of the closure assembly.
[0072] In reference now to the figures, the system allows the installation of two or more adjacent skylights in an end to end fashion along the major rib structure of a building's metal roof panel profile.
[0073] The skylight system may be applied to various types of ribbed roof profiles. FIG. 1 is a view showing the roof profile of a metal roof of the type known as the standing seam roof panel 10 . These include the “standing seam” roof, which has trapezoidal major ribs 12 typically 24″ to 30″ on center. Each panel 10 will also include the panel flat 14 , having a shoulder 16 and seamed at adjacent panels forming a standing seam 18 , which is folded over and seamed to prevent water from penetrating the roof.
[0074] FIG. 2 is a view showing the roof profile of a metal roof of the type known as an architectural standing seam roof, produced of a series of overlapping architectural standing seam panels 20 . Each panel 20 comprises a panel flat 24 , with an architectural standing seam 28 formed at the interconnecting panels.
[0075] FIG. 3 is a view showing the roof profile of a metal roof of the type commonly referred to as an R panel or exposed fastener panel 30 , with each panel having a rib 32 , panel flat 34 . Adjacent R panels are secured to the roof through a structural fastener 35 , and at the shoulder 36 which is formed from overlapping regions, or side lap 38 , the adjacent panels are secured through a stitch fastener 39 . The trapezoidal major ribs of the R panel roof are most typically formed at 8″ to 12″ on center.
[0076] FIG. 4 is a view showing the roof profile of a metal roof of the type commonly referred to as a snap rib seam panel 40 . Snap seam panels 40 have a panel flat 44 and a standing seam or snap seam 48 at adjacent panels.
[0077] FIG. 5 is a view showing the roof profile of a metal roof of the type commonly known as foam core panel 50 , which has a rib 52 , a liner panel 53 , a panel flat 54 and a foam core 57 . Side laps 58 are secured by a stitch fastener 59 . This panel is typically installed from the interior of the building.
[0078] The system includes a rail and closure assembly adapted to be supported onto the major elevations, seams, rib structures, or other structural elements of such roof profiles, where the standing structure provides the support, and the skylight is secured through an opening formed in the intervening, non-structural roof flat region.
[0079] Turning now to FIG. 6 , there is shown an exemplified rail and closure assembly 100 adapted for attachment to a standing seam panel roof 110 . While the following figures depict such an assembly, it will be understood that the components could easily be adapted, by shaping of the elements, for attachments to any roof system that has a profile with elevations providing a place for structural support.
[0080] Looking again to the figures, particularly FIGS. 6 and 7 , there is shown such a standing seam panel roof 110 having structural and other elements including a raised rib 112 , a panel flat 114 , shoulder 116 and standing seam 118 . Also depicted are the ridge cap 120 of the roof structure, and a series of cutaway regions, or gaps 122 formed to accommodate the structure, as described more fully as follows.
[0081] Shown as part of the system, and exemplified in this case, is a skylight 130 , generally comprising a skylight frame 132 and skylight lens 134 . While the figures depict a skylight, it will be understood that the system could also be adapted for use with any number of roof penetrating structures, from various types of skylights to smoke vents or other ventilating structures, which can all be adapted to be supported on the rail and closure assembly system.
[0082] Again in reference to FIGS. 6 and 7 , the system includes a rail and closure structure 146 , generally comprised of side rails 142 and 144 , and upper diverter 146 disposed at the rib cutaway section, or gap 122 . At this gap 122 a plate 148 may be located under the gap 122 to prevent water leakage from roof. In assembling the rail and closure structure to a roof, the plate 148 may be sealed and fastened securely to the roof panel supports.
[0083] Looking more particularly to FIG. 7 it is shown how the gap 122 in the roof rib 112 allows water flow 200 along the roof surface, over plate 148 , and down and away from the roof ridge cap 120 .
[0084] The rail and closure assembly structure 140 may also include a lower closure 150 to seal the system from the elements.
[0085] In reference now to FIG. 8 , there is shown a cross section through the skylight 130 region of the rail and closure structures 100 , showing the securement of the assembly 100 to the standing seam panel roof 110 . In particular, FIG. 8 depicts the use of the rib 112 to support the side rails 142 and 144 . It is seen that each rail 142 or 144 , has a rail upper flange or bearing surface 240 and a rail shoulder 242 . The rail 142 or 144 is secured to the skylight frame 132 by the a fastener 300 .
[0086] The rail shoulder 242 is shaped to fit closely over outside of the roof rib 112 , and is secured to roof rib 112 by a rivet 310 . The rail bearing surface 240 supports the skylight frame 132 , where a sealant 330 can be applied to seal against the passage of water or air.
[0087] FIG. 9 depicts a variation of the rail and closure assembly 100 shown in FIG. 8 , only where the rail shoulder 242 is shaped to fit closely along the inside of the roof rib 112 , and is secured to roof rib 112 by rivet 310 . As for FIG. 8 , the rail bearing surface 240 similarly supports the skylight frame 132 , where a sealant 330 can be applied.
[0088] It can be seen that the rail and closure structure 140 of the assembly 100 can be produced to fit closely along the contour of the roof 110 , and can be so configured to have end portions that match the contour of the ribs 112 . The various mating surfaces of the structure 140 and the roof 110 can be sealed in various ways known to the roofing art, including caulking or tape mastic, or various rubber fittings or inserts can be provided be used to seal the open area of the panel roof.
[0089] In FIG. 10 a partially cut away perspective view of the rail and closure structure 100 is used to show the support of the rail and closure system by the standing seam panel roof 110 , particularly the elevated rib 112 providing the structural support. In FIG. 10 it is seen how the rail and closure system incorporates the structural profile of the upper panels of metal roof structure, the elevations and ribs used in sealing adjacent panels, to provide the support of adjacent skylights. In this fashion, the system adopts various advantages of a standing seam roof.
[0090] Most standing seam roofs are seamed using various clip assemblies that allow the roof to float, along the major elevation. Typically, the roof is fixed at eave and allowed to expand and contract over at ridge. Very wide roofs can be fixed at midspan and expand towards both the eave and ridge. The design of the skylight system takes full advantage of the floating features of contemporary roofing structures, and when a skylight is so secured to the elevations, the skylight assemblies themselves are able to draw strength from the structural load bearing capacity of the roof profile.
[0091] Shown in FIG. 10 is the panel flat 114 , rib 112 and shoulder 116 , as well as the standing seam 18 . The ridge cap 120 is also shown, as well as the gap in the roof 122 .
[0092] The skylight 130 is supported on the rail and closure structure 140 , as previously described.
[0093] The rail and closure structure 140 is secured by its side rails 142 and 144 by a series of fasteners 300 to the skylight frame 132 and to the ribs 112 by a series of rivets 310 .
[0094] In application, from each structure 140 a single rib 112 is typically cut away to accommodate drainage at the high end of the system (toward ridge cap 120 ). This is an important feature for standing seam, architectural standing seam and snap seam roofs. Two ribs may be cut for roofs having an “R” panel profile.
[0095] The retained portions of rib 112 serve as a beam to support the side rails 142 and 144 and maintain a watertight seal along the length of the assembly. Internal portions of the ribs 112 may be removed to allow additional light from the skylight 130 .
[0096] A single bearing plate structure 148 is used for sealing the cut away rib. The bearing plate 148 also provides some support to link adjacent rib elevations 112 , and is typically produced of steel or other material sufficient to provide a rigid substructure to the skylight rail and closure structure.
[0097] The rail and closure structure 140 is shaped in such a manner that the skylight can be easily fastened directly to the rail portion, with rivets or fasteners such as screws and the like. The rail and closure structure 140 may also be designed to accept a safety security guard before the skylight is installed.
[0098] Looking now to FIGS. 11 through 13 , an upper or high end diverter 146 provides closure and diversion of water around the top of the assembly to an adjacent panel flat. Diverter 146 also provides a weather tight seal at the upper end of the assembly, with the plate 148 (not shown). In reference to the side rails 142 and 144 of a standing seam panel roof 110 , the diverter 146 generally fits the profile of the rib 112 at the region of the cut away gap 122 . The side rails 142 and 144 abut the diverter 146 and the height of the diverter 146 closely matches them in height. The upper flange 400 of the diverter 146 actually acts with upper flanges 240 of the side rails 142 and 144 to form the bearing surface of the skylight frame.
[0099] The diverter 146 lower flange 410 runs along the panel flat 114 . The diverter 146 also has a diversion surface 420 and fastener holes 430 along the lower flange.
[0100] At one end is a rib mating surface 440 and at the other a rib sealing plate 450 is formed,
[0101] FIGS. 14 through 16 shows the low end closure 150 that is used to maintain a weather tight seal at the lower end of the assembly. Shown again in reference to the side rails 142 and 144 of a standing seam panel roof 110 , the closure 150 is adapted to fit the profile of the rib 112 . The side rails 142 and 144 abut the closure 150 and the height of the closure 150 matches them in height.
[0102] Looking to the closure 150 , it is seen to have an upper flange 500 and a lower flange 510 , as well as a closure web 520 . The lower flange 510 includes fastener holes 530 .
[0103] The closure 150 also includes rib mating surfaces 540 and 550 to provide a tight fit along the ribs 112 .
[0104] Looking now to FIGS. 17 and 18 , the adaptation of the system for the application of multiple roof penetrating structures is described. A chief aspect of the assembly 100 is the reduction in the number of roof penetrations required to provide daylight to the interior of a structure, as fewer, longer cuts can be made along the roof elevations. These minimized openings can be maintained along a single rib, if desired, with one continuous opening versus many smaller ones permitting an equal or greater amount of ambient light into the building.
[0105] In the case of standing seam roofs the system provides the ability to remove only a portion of the bottom flat of the panel. This maintains the structural integrity of the roof in that multiple sections of major panel elevations are not removed, as is done to accommodate a “typical” curb assembly. Thus, the roofs structural integrity is not compromised to that extent and there are fewer potential areas for water infiltration, in that the skylight panels can be attached very near the ridge of the building and run to the cave requiring water to be diverted only once near the ridge of the roof plane and only across one panel flat.
[0106] To the limited extent that cutaways are made to the elevations, these are made small, on the order of a few inches or less, solely for the purpose of allowing drainage past the skylights.
[0107] The rail system is designed to install to either the inside or outside of the major rib elevation for any of the aforementioned roof panel profiles.
[0108] The rail and closure assembly 100 is particularly useful for continuous runs of skylights end to end. FIG. 17 shows how two adjacent skylights of the rail and closure assembly 100 can be affixed along a standing seam panel roof 110 . Instead of producing the lights with diverters and lower closures, where adjacent lights abut, the rail and curb structures 140 are provided with upper and lower standing rib frames 600 and 610 at adjacent ends of the adjacent structures 140 . A batten 620 is provided to secure the system 100 against the elements.
[0109] FIG. 18 is a side elevational view of the batten 620 , showing how it fits over the adjacent upper and lower standing rib frames 600 and 610 .
[0110] As only one example, skylights can be produced in units of up to 10 feet long, and connected in this fashion for as long as necessary, as each skylight unit is supported by the primary rib of the profile. The standing rib elevation (the major corrugation) runs longitudinally along the length of the assembly and mates along the entire assembly 100 , regardless of the number of adjacent structures 140 . No water can enter over the top of the rail and closure assembly.
[0111] Where it is desired that the skylight starts at the ridge of the roof, a simple flashing can be inserted under the ridge cap.
[0112] Where the ridge cap has a configuration to fit the rib elevations (major corrugations) in the roofing panels, a portion of the one rib may be cut out (approximately 2″), allowing the water from the roof panel above to be diverted on to the next panel.
[0113] If desired, a simple rail enclosure extension could be used to increase the height or distance between top skylight frame and the roof panel, and can be adapted to simply lay over or attach to the top of the rail and closure assembly. Such an extension could be produced to rest along the upper flange of the rail and closure assembly, to effectively raise the height of the skylight or smoke vent to accommodate different skylight depths or other design features, or to accommodate snow conditions and the like. In this fashion, the rail and closure structure can be produced to a standard height, with varying extensions used to elevate the overall height of the structure for such varied purposes. Various forms for such an extension would be suitable, and the skilled artisan will understand various ways and means of designing and manufacturing these to accomplish the goal of added height to the skylight.
[0114] While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of this invention. | The invention provides a side rail for attachment to elevated rib structure of a metal panel roof whereby the rib structure underlies and supports the side rail and any load being supported by the side rail. First and second side rails can be attached to next adjacent rib structures, thereby supporting the load from first and second next adjacent ones of the rib structures. End closures can extend across the space between such first and second side rails at opposing ends of the side rails, thereby closing off the openings between the ends of the side rails and providing a closed support structure extending about the encompassed space and closing off laterally-directed access to the enclosed space. | 4 |
RELATED APPLICATIONS
The present application claims priority based on Provisional Application No. 60/133,446, filed May 13, 1999.
FIELD OF THE INVENTION
The suppression of tremors in the extremities of human beings.
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for treating tremors in the extremities of humans. Tremors in humans are associated with several medically defined disorders. One such disorder is Essential tremor. Parkinson's disease is another such disorder. Those who suffer from such disorders experience excessive and involuntary oscillation of their limbs, which results in loss of control of attempted performance of an action or attempted maintenance of a postural position.
Present methods of treating such tremor disorders include medication such as Propranolol, Primidone, and Benzodiazepines, but these are often poorly tolerated and/or lose efficacy with prolonged treatment. A procedure known as “deep brain stimulation” has also been used with some success, but it is not effective for some patients and has the disadvantages of high expense and the risk of intracerebral hemorrhage or stroke. In addition, this procedure, which involves drilling a hole through the skull and into the brain, is subject to the difficulty that gaining access to the desired part of the brain is more difficult in some subjects that others.
Historically, deep brain stimulation has involved the creation of subcortical lesions in the thalamus and, in some cases, in the ansa lenticularis. Other tremor disorders that have been found to respond to a lesion in the thalamic area, particularly in the ventrolateral nucleus of the thalamus or just anterior to the posterior ventral lateral nucleus, are, in addition to Parkinson s disease and Essential cerebellar tremors, dystonia musculorum deformans, hemiballismus, tardive, dyskinesia, and chorea. However, given the fact that deep brain stimulation is drastic surgery, it is often not used with patients who have relatively mild tremor systems.
In this regard, some diseases which produce tremor symptoms are progressive at a relatively rapid rate, e.g., Parkinson's disease, while others are not, e.g., Essential tremors.
Given the fact that medication has proved unsatisfactory as a treatment for tremors and given the further fact that drastic surgery such as deep brain stimulation is not generally used to treat mild tremors, a need for a method and means for effectively treating mild tremors as a stand-alone treatment or as an adjunct to other treatments has long existed, as well as a similar need for effectively treating severe tremors.
The precise pathophysiology of Essential tremor is unknown, but it is believed to involve the cerebellum. The cerebellar outflow to the thalamus appears to be critical, and the cerebellar-thalamic projection site is the frequent target of neurosurgical therapies for intractable Essential tremor. Thus, similarity to the surgical treatment for intractable tremor in Parkinson's disease can be seen.
The peripheral nervous system appears to play a critical role in Essential tremor. Beta-adrenergic receptor blocking medications that do not block the brain have some efficacy against this disorder. Essential tremor patients, like those with focal dystonia, often utilize “sensory tricks” such as touching the chin to suppress tremor, or touching the dorsum of the hand to suppress writing tremor. During the act of writing, it has been observed that tremor worsened if the hand is not permitted to touch the writing surface, such that afferent sensory information about the position of the hand is minimized. Such maneuvers may well enhance musculotendinous afferents to the cerebellum, thereby suppressing tremor.
SUMMARY OF THE INVENTION
The present invention provides a non-invasive method of controlling tremor. While the exact mechanism of the present invention is not known with certainty, it is believed likely that enhancement of muscular and tendon afferent sensory function is involved.
In any event, the present invention involves the application of external pressure to certain areas of the patient's body to control tremor. Preferably, this pressure is applied by using a pressure-applying cuff. It is believed that such pressure activates musculotendonis afferents with the result that tremor is controlled or suppressed, but the present invention is not to be tied to that belief.
The desired locations for placement of the pressure cuff are the wrist, above and or below the elbow, and such other locations as may be found to be effective. When placed on the arm, the location of the cuff will typically be within about 5 inches above or below the elbow. When placed on the wrist, the location of the cuff will typically be within about 3 inches of the base of the hand. The location of the pressure cuff may be dependent upon the location of the tremor which it is desired to control or suppress. More than one cuff may be used simultaneously, e.g., one on the wrist and one above and/or below the elbow.
The desired amount of pressure is, because of patient differences, a wide range of pressure, but an effective tremor suppressing pressure can easily be determined empirically, simply be observing the effect on the patient as pressure is applied and increased to the appropriate level. The duration of pressure application is similarly determined empirically. Tremor suppression in legs can be accomplished in the same manner by applying pressure to the area above the ankle or the area above or below the knee. The location, amount and duration of pressure are determined empirically.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a pressure cuff suitable for use in the present invention.
FIG. 2 shows useful locations for the placement of the cuff of the present invention.
DETAILED DESCRIPTION
A preferred embodiment of the cuff, or brace, of the present invention in shown in FIG. 1 . As there illustrated, it can be seen that the flexible cuff, or brace, includes a strip of open pore foam 1 with reinforcing material, such as non-woven fabric, 2 bonded to the outside surface of the foam and a like fabric 3 bonded to the inside surface of the foam to facilitate a complete wrapping about a subject's forearm, wrist or other location. The flexible cuff 1 is also provided with a closure means which, in this embodiment, comprises a Velcro strip 4 and a mechanical loop 5 which is attached to cuff 1 .
In use, the flexible cuff is positioned at the desired location and pressure is applied by passing closure strap 4 through mechanical loop 5 and pulling on the strap until the desired degree of pressure has been applied. Because of the variability in magnitude of tremor and the variability in the causes of such tremor, it is not possible to quantify the precise pressure which will be appropriate and effective in any given case. However, the requisite degree and duration of pressure can be determined by the patient simply by adjusting the pressure applied by tightening or loosening the strap until control or suppression of the tremor is achieved.
Referring now to the drawing, there is shown flexible brace employing the principles of the present invention, finding general utility for relieving the tremor symptoms prevalent in Essential and Parkinson's type tremor and affecting the aging population. The brace is formed of a laminated strip which includes a relatively soft, fluid (perspiration) passing material 1 such as an open pore urethane foam, and a fabric 2 (woven or nonwoven) which acts as a perspiration wicking agent.
In accordance with one aspect of the present invention, the inner surface of lamination operates with a reinforced trap 4 to form a complete circumferential contact with the subject's wrist or arm near the elbow. The strap may comprise cloth, or a laminate as of open pore foam and cloth, or similar material. The reinforced strap 4 is preferably somewhat narrower than the backer strip 6 and the mechanical loop 5 so it can freely pass through aperture in loop 5 which is attached to backer strip 6 . The strap 4 is fastened to the backer by passing through a slot and being wrapped around to meet on itself and be permanently connected by means of sewing or other bonding technique.
The loop 5 may be completely formed when the member is prepared (e.g., molded) or, alternatively, the requisite loop aperture may be formed by a separately attached bar. To this end, the separately attached bar may be in the form of a rectangle with projection such that its ends pass into retaining apertures formed in the outer member and are permanently joined to member. In any event, the free end of the strap passes through the aperture. Alternatively, the slot may be directly formed into the backer.
The composite flexible cuff, or brace, shown in the drawing is affixed in position by the subject who simply passes his arm through the slack loop formed by the inner laminate strip and strap (assuming t hat the strap end has already passed through the aperture). The subject simply pulls the end of the strap back upon itself until the desired degree of tightness has been achieved.
To lock the flexible brace in place, one part of a mating fastener system is fixed on the outer surface of the laminated strip 2 forming one part of a rapid attachment, quick release system well known to those skilled in the art and sold, for example, under the trademark VELCRO. A mating strip to the element is located on the outer surface of the flexible material.
In use, the composite flexible brace is thus readily applied in the manner above described, and, as shown in FIG. 2, provides a firm, reliable mechanical pressure on the wrist or arm near the elbow, relieving the symptoms of tremor and permitting the function of the hands notwithstanding such condition.
The apparatus shown in FIGS. 1 and 2 is exemplary only. Many other constructions of a cuff or sleeve which apply pressure may be used to apply pressure in selected areas on the extremity or circumferentially.
Patient testing of the method and apparatus of the present invention has resulted in substantial overall suppression of tremor. Some patients benefited more than others and, in individual patients, some extremities benefited more or less than others, e.g., right arms as compared with left arms and vice versa.
Although the preferred embodiment of this invention involves the application of circumferential pressure, it is not necessary to do so. Once again, patient variability plays a role in defining the location in pressure can be effectively applied and specific locations can easily be determined empirically.
The foregoing description of the present invention and certain embodiments thereof is for purposes of illustration only and it is to be understood that the scope of the present invention is defined by the clams appended hereto. | A method of suppressing tremors in the extremities of human beings by applying pressure to at least one selected location on the extremity. | 0 |
This is a division of Ser. No. 915,025, filed June 12, 1978, U.S. Pat. No. 4,253,904.
BACKGROUND OF THE INVENTION
The present invention relates to the decoration of bottles and the like, and more particularly to decoration of bottles by means of heat transfer labelling.
Decorating systems using heat transfer labels have received widespread commercial acceptance over the last decade. Such decorating systems are typically characterized by conveyors for feeding the objects to be labelled, usually bottles; a turret for sequentially positioning the bottles at a labelling station; a feed mechanism for transporting labels supported by a carrier strip to the labelling station, and a device for pressing a label against an adjacent bottle at the labelling station. Examples of such systems appear in U.S. Pat. Nos. 2,981,432; 3,036,624, 3,064,714; 3,208,897; 3,231,448; 3,261,734; 3,313,667; 3,709,755; and 3,861,986.
A particular requirement in designing turrets which may be used in labelling non-rigid articles, such as plastic bottles, is that some means be included to maintain the shape of the bottle during the label transfer, which typically involves significant pressures on the bottle face. A solution which has been widely adopted to meet this problem is the inclusion of a device to inflate the bottles during transfer, thus maintaining their shape through internal air pressure. Such devices are exemplified by that disclosed in U.S. Pat. No. 3,064,714 (cf. FIG. 5; cols. 3,4). Any inflating device must be synchronized in operation with the remainder of the labelling apparatus. It is desirable that the controlling apparatus for such inflating devices operate quickly and reliably. Furthermore, well-designed inflation control apparatus should be usable with turrets of different sizes and constructions. Inflation apparatus in the prior art inadequately satisfies these criteria.
Typical label carrier feed apparatus utilizing a method which is adopted in principle in the carrier transport of the invention is disclosed in U.S. Pat. No. 3,208,897. The main constituents of this type of transport are the label-bearing carrier strip, feed and guide rolls (the latter are dancer and idler rolls), a meter roll, two shuttle rolls, and cams with followers regulating the motion of the shuttle rolls.
The feed mechanism for transporting the carrier strip with labels to and from the labelling area must be carefully timed so that during labelling the carrier strip will be moving at the same speed as the tangential speed of the bottle to be decorated. The linear speed of the pressing means, label-carrier strip, and bottle surface is a critical limiting factor in heat transfer labelling; the quality of the transfer deteriorates if this speed is too high.
In the carrier strip transport systems typified by that disclosed in the above patent, the carrier strip speed is regulated by establishing a basic strip speed (registered by the meter roll) which represents a desired average rate of advance over the entire labelling cycle, and modifying this basic strip speed in the region of transfer so that it equals the more rapid linear speed of the bottle surface during transfer. The user may space the transfer labels fairly closely together on the carrier strip, as the same speed modifying means retards the advance of the carrier strip between labelling periods. The shuttle rolls and cams regulating their motion are used to locally modify the basic carrier transport speed. In all of these prior art decorating devices, "dwells" or idle periods are included in the rotation of the turrets in order to facilitate the loading and unloading of articles to be decorated. This requires a retarding period in the strip speed modifying means which is equal in duration to the accelerating period, and presents a severe limiting factor in the production rates of these decorators. Furthermore, the reciprocating motion of such prior art shuttle rolls is of undesirably large amplitude. This generally requires larger components and introduces greater disturbing forces, thus causing significantly increased mechanical problems. Ultimately, this imposes speed limitations on the carrier transport.
Accordingly, it is a principal object of the invention to provide decorating apparatus of the type described above with increased efficiency and higher production rates. A related object of the invention is to provide more reliable mechanical operations in such apparatus.
Another object of the invention is to achieve a turret with improved inflating apparatus for non-rigid articles to be labelled. A related object of the invention is to provide inflating apparatus of rapid, timely operation. Another related object is to avoid the need to redesign such inflating apparatus when used in turrets of varying size or construction.
A further object of the invention is to incorporate into the decorating apparatus a label carrier strip transport which may be used in conjunction with a continuously rotating turret. A related object of the invention is to modify the carrier strip speed in the labelling area to provide a relatively long accelerating period during labelling and a relatively brief retarding period in the interim. Yet another object of the invention is to reduce the magnitude of the reciprocating shuttle roll motion.
SUMMARY OF THE INVENTION
In accomplishing the above and related objects, the high speed decorator of the invention includes input and output star wheels, a continuously rotating turret having bottle holding and bottle inflating means, a label carrier strip transport with speed modification in the labelling area, and label preheating and pressing devices. Bottle inflation is effected upon the insertion of an air nozzle into the bottle, and is regulated by valving apparatus controlling the position of the nozzle and the flow of air therethrough. A basic speed of the label carrier strip is increased in the labelling area during the greater part of the labelling period, and retarded during the relatively short time between labelling.
In accordance with one aspect of the invention, the high speed decorator includes a continuously rotating turret, with no "dwells" for insertion or removal of bottles. Bottles are inserted and removed during turret rotation by adjacent star wheels.
In accordance with another aspect of the invention, the raising and lowering of inflating nozzles is controlled by the operation of a valve plate assembly which predicates the vertical position of the nozzle upon the angular position of the nozzle and associated bottle. The valve plate assembly includes an upper stationary plate and a lower plate which rotates in conjunction with the turret. The upper plate contains pressurized and venting apertures which take the form of annular zones and is in a face seal with the lower plate. The lower plate contains ports, each of which contacts either a venting zone or pressurized zone at any point of rotation, causing the port to be pressurized or vented.
In accordance with a further aspect of the invention, each of the inflating nozzles is mounted on a tube which is in turn coupled to a piston within an actuating cylinder. The actuating cylinder contains upper and lower outlets which are connected by air lines to ports in the rotating valve plate. Pressurization at one outlet and venting at the other effects a raising or lowering of the piston and connected air nozzle.
In accordance with yet another aspect of the invention, the flow of air through the inflating nozzle is automatically initiated upon the lowering of the nozzle, and terminated on the raising of the nozzle. This is accomplished by the confinement of the nozzle-carrying tube in a piston valve assembly. The lowering of the tube through the piston valve assembly causes the connection of a duct in the tube to a source of low pressure inflating air and the raising of the tube breaks this connection.
In accordance with an additional aspect of the invention, the label carrier strip transport is a variant of the formerly disclosed apparatus employing local speed modification by shuttle rolls, reciprocating slides, and a regulating cam. A conjugate cam is employed to provide asymmetric reciprocation of the slides. During the majority of the period, the throw of the conjugate cam causes the movement of the shuttle rolls toward the left, locally accelerating the carrier strip motion for the purpose of label transfer. During the relatively short period between transfers, the cam throw causes a rapid return of the shuttle rolls. In a preferred embodiment of the invention, an approximate temporal ratio of three to one is employed for the accelerating and return periods.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of the high speed decorator of the invention will become apparent in considering a preferred embodiment of the decorator in conjunction with the drawings in which:
FIG. 1 is a partial elevation view of a two bottle turret;
FIG. 2 is a cutaway view of a piston valve assembly shown in cooperation with adjacent parts of the turret of FIG. 1;
FIG. 3A is a bottom plan view of the lower valve plate of FIG. 1;
FIG. 3B is a top plan view of the lower valve plate of FIG. 1;
FIG. 4 is a section along the lines 4--4 of FIG. 3B;
FIG. 5 is a section along the lines 5--5 of FIG. 3B;
FIG. 6A is a bottom plan view of the upper valve plate of FIG. 1;
FIG. 6B is a top plan view of the upper valve plate of FIG. 1;
FIG. 7 is a section along the lines 7--7 of FIG. 6A;
FIG. 8 is a section along the lines 8--8 of FIG. 6A;
FIG. 9 is a partial plan view of the label carrier strip transport and the area of label application;
FIG. 10 is a schematic view of the conjugate cam and associated followers of FIG. 9, as seen from above;
FIG. 11 is a plot of the linear position of a cam follower against the angular position of the conjugate cam of FIG. 10.
DETAILED DESCRIPTION OF THE INVENTION
Reference should now be had to FIGS. 1 through 11 for a detailed description of the invention. The high speed decorator of the invention includes a continuously rotating turret 100, having bottle holding and inflating components, input and output star wheels 350 and 360, a label carrier strip supply and transport 300, and a label applying device 310. The functions performed by the above apparatus may be combined with prior and subsequent processing steps, such as preheating and postheating of the bottles, as is well known to skilled practitioners of the art.
FIG. 1 illustrates a particular embodiment of a turret assembly 100 including bottle inflating apparatus in accordance with the invention. The turret assembly, in decorating machines of this type, acts to engage bottles presented to it by an input conveyor or other means, rotates these bottles to the site of label transfer and past the label carrier strip at a predetermined linear (tangential) speed, and after further rotation releases the labelled bottles for further processing. When designing a turret for non-rigid articles such as plastic bottles, some means of inflating the bottles during the labelling period is advantageously incorporated.
An illustrative turret assembly 100 includes a rotatable central shaft 120 which is housed in a stationary base (not shown). A platform 110 rotates along with shaft 120. Spiders 101, 102, 103, and 104 have bottle holding stations, and are similarly rotatable. The turret assembly shown accommodates two bottles B 1 and B 2 , but it is equally possible to use the inflating apparatus of the invention with turrets holding more than two bottles.
A bracket 141 is firmly secured to central shaft 120, and carries two piston valve assemblies 160 and 165, one on each side. Each piston valve assembly is adapted to allow the projection and retraction of a tube (150, 155) to which is appended an air nozzle (151, 156). Each tube has a vertical orientation.
The raising and lowering of tube 150 relative to piston valve assembly 160 is controlled by actuating cylinder 170. When air pressure is applied to cylinder 170 through air hose 171, a piston (not shown) in cylinder 170 is forced downward, thereby expelling the air from the lower part of cylinder 170 through air hose 173. This causes tube 150, to which the piston is coupled, to be lowered through cylinder 160 until nozzle 151 rests in the bottle mouth, as shown. When air pressure is released from hose 171 and applied through hose 173, the converse process occurs and tube 150 is retracted from the mouth of bottle B 1 . An identical process occurs in cylinder 175, although at different times. Means for effecting these air pressure differentials are discussed infra.
FIG. 2 illustrates the internal valving arrangement within one of the piston valve assemblies (assume assembly 160). Through this valving, the projection and retraction of tube 150 is coordinated with the flow of air through nozzle 151, which thereby emits air only when the nozzle is inserted into a bottle. Piston valve assembly 160 is secured to bracket 141, and in turn carries a smaller diameter air cylinder 170 (shown in part). Air cylinder 170 is advantageously screwed into assembly 160 at the top of a central bore 164 in the latter. A piston (not shown) within air cylinder 170 is connected by piston rod 172 to the top of tube 150. Central bore 164 houses two bushings 154, which have an inner diameter permitting the restricted vertical movement of tube 150. These bushings create between them a circumferential chamber 163, which receives a steady supply of low pressure air from air line 161 via connecting passage 162. Tube 150 contains a central duct 152 which connects the outlet of nozzle 151 to an aperture 153 in the side of tube 150.
When the piston in air cylinder 170 is down, causing tube 150 to be lowered as shown in FIG. 2, aperture 153 communicates with chamber 163, and low pressure air passes through duct 152 and out nozzle 151. When tube 150 is raised, aperture 153 no longer communicates with chamber 163 and the flow of air is interrupted.
With further reference to FIG. 1, a protective housing (not shown) is advantageously placed around the section of rotating turret 100 between bracket 141 and a rotating valve plate 181, inclusive. An enlarged segment 121 of the rotating central shaft carries two face valve plates, 181 and 183. Lower plate 181 is secured to the rotating shaft 121 and rotates therewith, whereas upper plate 183 is secured to a stationary supporting member (not shown), and does not rotate. Air line 185 feeds high pressure air into an aperture in upper plate 183 for the purpose of raising and lowering the pistons in air cylinder 170 and 175. This air passes through one of air hoses 171, 173, 176, or 178 when a corresponding port in lower plate 181 rotates to a point of coincidence with a pressurized groove in upper plate 183. This is discussed more fully infra.
Low pressure air is also fed through air line 189 for the purpose of inflating bottles via air lines 161 and 166 (see FIG. 1). This air passes through rotary joint 188, through duct 186 in rotating shaft 121, and thence into channels in lower plate 181, as discussed within.
Air which is vented from culinders 170 and 175 eventually escapes through outlet 187 from channels in stationary plate 183.
FIGS. 3A, 3B, 4 and 5 show in various views an embodiment of the lower valve plate 181 to be used in conjunction with a two bottle turret. Valve plate 181, which is a face seal plate, rotates along with central shaft 121. In the bottom plan view of FIG. 3A, lower plate 181 has an essentially flat face 200 in which six ports, 201b through 206b, appear. In a plate for an N bottle turret, N groups of three ports would be symmetrically placed on face 200. With reference to a given group of ports 201b, 203b and 205b, the outermost port, 201b, is at a radius r 1 , port 203b is at smaller radius r 2 , and port 205b is at the smallest radius r 3 . Ports 203b and 205b lie on different radii which are illustratively separated by an angle of 40°, with port 201b on the bisecting radius. Bottom face 200 has diameter D 1 . The various ports in face 200 are machined to allow the connection of air lines from cylinders 160, 165, 170, and 175. Air line 161 is connected to port 201b, air line 171 is connected to port 203b, and air line 173 is connected to port 205b. Similarly, air line 166 is connected to port 202b, air line 176 to port 204b, and air line 178 to port 206b.
In the top plan view of FIG. 3B, valve plate 181 has an elevated face 210 of diameter D 2 and an indented face 220 of diamater D 1 , where D 1 is somewhat larger than D 2 . Only four ports, 203t, 204t, 205t, and 206t can be seen in this view, and these are somewhat smaller than the corresponding ports in the bottom face, as can be seen by comparison with the surrounding dotted outlines. The projected locations of ports 201t and 202t are also shown in dotted outline.
FIG. 4 illustrates a sectional view of plate 181 taken through the section 4--4 of FIG. 3B, which passes through ports 203t and 204t. The elevated face 210 of plate 181 contacts the lower face of stationary upper plate 183. These two faces should be lapped to very flat surfaces, in order to assure precise valving action and minimum air leakage. An axial cavity 225 in lower plate 181 allows the plate to be fitted and secured to rotating central shaft 121. Two vertical channels 203c and 204c connect upper ports 203t and 204t with lower ports 203b and 204b. These channels narrow toward the top of lower plate 181 in order to provide superior valving action.
FIG. 5 depicts a sectional view of valve plate 181 taken along the section 5--5 in FIG. 3B, which passes through projected ports 201t and 202t. In this view, it can be seen that two L-shaped channels, 201c and 202c, connect the axial cavity 225 with lower ports 201b and 202b, respectively. The horizontal segments of these cavities are advantageously drilled from the perimeter of valve plate 181, and the outermost sections then plugged. These channels are used to feed low pressure air to bottle-inflating air lines 161 and 166. Low pressure air passes through duct 186 in central shaft 121 (see FIG. 2), and into channels 201c and 202c, which are connected to air lines 161 and 166. These air lines are therefore constantly pressurized. The enlarged central portion of axial cavity 225 provides an annular chamber around the outlets of duct 186, thus eliminating the need to precisely align these outlets with channels 201c and 201d.
FIGS. 6A, 6B, 7, and 8 display various views of upper valve plate 183. This plate remains stationary during the rotation of turret 100. The bottom plan view of FIG. 6A shows a bottom face 250 which contacts the upper face of valve plate 181, and which has approximately the same diameter D 2 as the elevated face 210 of lower plate 181. Face 250 has alternating raised and recessed annular regions, with the latter serving as pressurized or venting regions. More specifically, there is a peripheral raised band 255, an outer venting region 260 (recessed), a raised border strip 271 which defines an interior pressurized region 270 (recessed), an inner venting region 265 (recessed), and a raised central area 280. In addition, there is an axial cavity 285 similar to cavity 225 in lower plate 181.
The essential features of bottom face 250 which lend upper plate 183 its valving characteristics are found between outer band 255 and central area 280. The two venting regions 260 and 261 merge in the sector between radii R A and R D , and are vented through venting ports 261b and 262b in this area. This sector encompasses 40°. The pressurized region 270 has a profile defined by raised border strip 271, which is best characterized by reference to the four radii R A , R B , R C , and R D in FIG. 6A. Pressurized region 270 covers the angle from R A clockwise to R D . 270AB or the section of region 270 from R A to R B , has a mean radius of r 2 and a width equalling the radial demension of port 203t. Thus, when valve plates 181 and 183 are coaxially joined and port 203t (at radius r 2 ) falls within sector AB, it will communicate with region 270AB. 270CD is at mean radius r 3 and of the same width as 270AB, thus ensuring contact with port 205t when this port falls within sector CD. Region 270BC represents a merger of the two above regions in sector BC, plus the area covered by the intervening border strip 271. Thus, both 203t and 205t will fall within 270BC. Pressurizing port 275b lies within 270AB. Region 270BC illustratively encompasses an angle of 40° (identical to the angle of separation of 203t and 205t).
As seen from above, in the plan view of FIG. 6B, plate 183 has a plain outer band 290 in which lies pressurizing port 275t, an indented face 295, and axial cavity 285.
FIG. 7 shows a sectional view of upper plate 183 in the section 7--7 of FIG. 6A, taken through pressurizing port 275t and venting ports 261b and 262b. On the left can be seen pressurizing channel 275c, which terminates in port 275b in region 270BC of lower face 250. Pressurizing port 275t is connected to a source of high pressure air, 185 (see FIG. 1). Two venting grooves, 260 and 265, also appear. On the right, the two venting ports 261b and 262b in lower face 250 feed into a venting channel 263. Venting channel 263 terminates in outlet 187 (see FIG. 1).
In the sectional view of FIG. 8, taken through 8--8 in FIG. 6A, somewhat different pressurized region and venting region profiles appear in bottom face 250. The purpose of indented face 295 is to allow the spring loading of upper plate 183 onto lower plate 181. This acts as a countervailing force against the tendency of plate 183 to be lifted by the high pressure air between the two valve plates. A hole 297 is reamed into the perimeter of upper plate 183 in order to allow the insertion of a pin (not shown). This pin is used to adjustably secure plate 183 to an external support (not shown), thus preventing the rotation of upper plate 183 while allowing a precise angular placement for valving purposes. Axial cavity 285 allows the free rotation of central shaft 121.
The operation of the above valving apparatus in the operation of turret 100 of the invention may be illustrated with reference to FIGS. 1 through 8. Spiders 101 and 102 on turret 100 engage a bottle B 1 while turret 100 is continuously rotating in a counterclockwise manner. At this time, port 203t is under sector DA, while port 205t (which lags by an angle of 40°) is in region 270CD. Thus, the bottom of actuating cylinder 170 is pressurized via air line 173, while the top is vented, and nozzle 151 is in the raised position. Shortly thereafter, port 203t enters region 270AB while port 205t roughly simultaneously enters sector DA. This causes high pressure air to pass through air line 171 while air line 173 is vented. A rapid downward movement of the piston (not shown) in cylinder 170 results, causing the insertion of nozzle 151 into bottle B 1 . Due to the valving in actuating cylinder 160 and lower valve plate 181, inflating air from air line 189 enters bottle B 1 . During this period, a label is applied to bottle B 1 .
Shortly after labelling, port 203t passes from region 270BC into outer venting region 260, while port 205t passes from region 265 into region 270BC. High pressure air therefore enters air line 173, while air line 171 is quickly vented to atmosphere. This causes the piston in air cylinder 170 to rapidly rise, and nozzle 151 to retract from the mouth of bottle B 1 . During this period, bottle B 1 is removed from spiders 101 and 102 and turret assembly 100 is in readiness for a subsequent bottle.
A second bottle B 2 undergoes the same process, but half a revolution later of turret 100. Thus, for example, if port 203t were in the middle of 270AB, and port 205t in 265, causing nozzle 151 to be down, port 204t would be in region 260, and port 206t in region 270CD, causing nozzle 156 to be up. This state is shown in FIG. 1. For turrets accommodating larger numbers of bottles, the phase lag would be commensurately smaller.
The above valving system possesses special advantages when employed in conjunction with the turret of the present invention. Whereas prior art turret motion invariably included idle periods, or "dwells", between the labelling periods during which the turret was in motion, the turret of the present invention is in continuous motion. The elimination of these dwells, which typically accounted for half the time consumed by the decorating cycle, therefore approximately doubles the production rate without increasing the velocity of decoration. The valving apparatus of the invention is well suited to this higher speed turret operation; by imposing minimal restrictions on the air lines, it allows high speed operation of the inflating apparatus.
This valving arrangement furthermore enjoys the advantage that it may be employed with any turret assembly which is designed to accommodate a given number of bottles, without any need to adapt to a change in bottle size. This is due to the fact that the design of valve plates 181 and 183 is simply a function of the number of bottles, and the lower valve plate 181 may be connected to cylinder 170 and assembly 160 (which might be moved in a turret for larger bottles) by flexible air hoses.
The use of a continuously rotating turret, with its advantages of higher production rates, imposes certain requirements on the input and output conveying devices. As there are no dwells during which to load bottles onto the turret and unload these after labelling, a device capable of transferring bottles to a moving turret must be used. The solution adopted in the present invention, which is known in the prior art, is the employment of star wheels 350 and 360 (see FIG. 9). A bottle B 1 , engaged by an input conveyor (not shown), is carried to star wheel 350 which transfers the bottle to the continuously rotating turret 100. After labelling, star wheel 360 removes the bottle from the moving turret and transfers it to an output conveyor (not shown).
The general organization of the label supplying and applying apparatus of the present invention is shown in FIG. 9. The label-carrier strip 305 is unwound from a spool 302 and fed at a constant, metered rate by a sprocket wheel 306 to and around a guide roll 307 at one end of a reciprocating slide 315. Carrier strip 305 is advantageously subjected to heating means (not shown) in order to preheat the labels in preparation for transfer. The carrier strip 305 passes adjacent to turret 100 where labels are pressed onto a surface of an article to be decorated by a freely mounted roller 310, which is adapted to move at the same linear speed as the carrier strip 305 during labelling. The carrier strip 305 then winds around a guide roll 308 at the other end of slide 315, around an idler roll 309, and is taken up on a spool 303. Rolls 311, 312, 316, and 317 are used to provide the desired carrier strip tension.
A conjugate cam 331 having lobes 333 and 335 is mounted on shaft 330, and engages followers 325 and 337 on a slide 320 in order to reciprocate this slide. Angularly adjustable cam block 327 acts through follower 323 to impart a proportionate part of the motion of the slide 320 to the slide 315 carrying rolls 307 and 308.
By means of the adjustable cam block 327, the slide 315 is given a stroke such that the speed of the label-carrier strip 305 is locally modified to accommodate the basic rate at which the strip is wound and unwound, determined by meter roll 306, and the more rapid speed at which labels are applied. By the same token, the strip speed modifying means reduces the basic strip speed during the periods between labelling.
In the high speed labelling method of the invention, bottles are presented at the labelling site 318 by a continuously rotating turret, with no dwell in the turret motion between labelling periods. This mandates strip speed modifying apparatus which will allow a relatively long labelling period and a relatively short label return period, as opposed to the equal periods of the prior art. This is accomplished by the incorporation of conjugate cam 331. The plan view of FIG. 10 shows a smaller upper lobe (shaded) 333 and a larger lower lobe 335. Follower 337, which is attached to slide 320, tracks upper lobe 333, while follower 325 tracks lower lobe 335. Follower 325 is attached to slide 320, and governs the motion of cam block 327 via follower 323. Followers 325 and 337 are separated by a constant distance throughout the cam rotation. Cam lobes 333 and 335 are advantageously fabricated as a single piece, and in any event do not rotate relative to one another.
The motion of cam follower 325 on the +y axis of FIG. 10 (taking the cam axle 330 as y=0) is plotted in FIG. 11. Approximately 270° of the cam rotation period is consumed by a linear rise of the follower position. During this period reciprocating slide 315 moves toward the left at a constant speed, causing a fixed increase in the speed of carrier strip 305 past the labelling site 317. During the balance of cam rotation, or approximately 90°, follower 325 returns to its original position at a more precipitous rate. Conjugate cam 333 and 335 may be contoured, as well known to those skilled in the art, in order to keep (d 2 y)/(dt 2 ) and (d 3 y)/(dt 3 ) within practical values.
It has been found that a smooth operation of the above label carrier strip speed modifying apparatus in conjunction with a continusouly rotating turret dictates an advantageous range of about 0.65 to 0.85 for the ratio of the strip accelerating period to the entire cam rotation period. The preferred valve for this ratio, illustrated by the plot of FIG. 11, is 0.75.
While various aspects of the invention have been set forth by the drawings and the specification, it is to be understood that the foregoing detailed description is for illustration only and that various changes in parts, as well as the substitution of equivalent constituents for those shown and described, may be made without departing from the spirit and scope of the invention as set forth in the appended claims. | Method and apparatus for the decoration of bottles and the like at high speeds. Bottles are delivered by an input conveyor to a star wheel, which deposits them sequentially into a continuously rotating turret. The turret carries the bottles past a labelling site, where a label carrier strip is pressed into contact with a bottle surface and a label thereby transferred. The shape of the bottle is maintained during labelling by means of inflation of the bottles through an inserted nozzle. The raising and lowering of the inflating nozzle and the flow of inflating air is controlled by special valving apparatus. The motion of the label carrier strip past the labelling site is regulated by the use of rolls on a shuttle slide, which in turn is reciprocated by a second slide driven by a conjugate cam. This results in an increase of the local velocity of the carrier strip during most of the cycle, and a slowing of the strip during the balance. After labelling, the inflating nozzle is retracted from the bottle and the bottle is removed by a second star wheel for further processing. | 1 |
BACKGROUND OF INVENTION
[0001] a. Field of Invention
[0002] The invention relates generally to manually actuated power sprayers for mounting to containers of liquids to be sprayed, and more particularly to a trigger operated power sprayer having improved container vent and product discharge controls during pump activation.
[0003] b. Description of Related Art
[0004] Manually actuated power sprayers, which are well known in the art, may include trigger sprayers adapted for manual operation in dispensing of product from a container attached thereto. During operation of the power sprayer, the container to which the manually actuated power sprayer is mounted must be vented to atmosphere to replenish the container interior with air as liquid product is dispensed. If the container is not properly and efficiently vented, the air volume or head space volume within the container which enlarges as the container is emptied of product eventually becomes sub-atmospheric thereby creating unwanted conditions of hydraulic lock and container collapse. Container venting may be carried out in a multitude of ways, utilizing both active and passive valving. While container vent control may be avoided when using, for example, a collapsible bag as the container of product is dispensed, there exist a multitude of containers and products on the market for which collapsible bags are unavailable or economically prohibitive.
[0005] For improved operation of the power sprayer for which venting is required, the function of the vent as well as the product discharge controls must be coordinated such that the container is adequately vented while product is being discharged. Container vent and product discharge valving must also be controlled such that during periods of shipping and storage and other periods of non-use, the vent and product discharge ports remain sealed closed to avoid the possibility of leakage. At the same time, the vent and discharge valve controls must be efficient and economical in use during operation of a power sprayer, and must likewise be efficient and economical to fabricate and assemble into the power sprayer unit.
[0006] Among conventional trigger sprayers having a container vent control is one with a flexible seal member for covering a vent hole to prevent leakage of product and to permit venting of the container during dispensing. Heretofore, conventional seal designs have been quite complex and have thus required relatively complicated manufacturing and assembly techniques. For example, conventional vent seals disclosed in U.S. Pat. No. 4,230,277, the disclosure of which is incorporated herein by reference, include non-geometric or complex geometric cross-sections, or protrusions or the like integrally molded therewith as in, for example, U.S. Pat. No. 5,603,434, the disclosure of which is also incorporated herein by reference. The fabrication and installation of such complex prior art designs can significantly increase the overall manufacturing and assembly costs of the trigger sprayer. Other effective container vent controls, as disclosed in U.S. Pat. No. 6,554,211, the disclosure of which is incorporated herein by reference, could also be improved upon in operation.
[0007] There thus exists room for improvement in the number of parts, the overall costs associated with manufacturing and assembly, as well as the operation of existing manually activated sprayers, whether such sprayers are of the manual pumping type or of the battery activated type, so long as such sprayers require container vent and product discharge controls.
[0008] It would therefore be of benefit to provide a manually actuated pump sprayer having in combination improved means for container venting and product discharge control operable in a repeatable and predictable manner over the life of the pump sprayer. There also remains a need for an improved means for container venting and product discharge control, which is robust in design, efficient to operate, simple to assemble and disassemble, and which is economically feasible to manufacture.
SUMMARY OF INVENTION
[0009] The invention solves the problems and overcomes the drawbacks and deficiencies of prior art container vent and product discharge control designs for manually actuated or battery operated sprayers by providing in combination improved means for container venting and product discharge control for improved sprayer operation.
[0010] The invention thus provides a manually operated sprayer for a container of liquid to be sprayed. The sprayer includes a variable volume pump means having liquid inlet means for connecting the pump means with liquid in the container, outlet means connecting the pump means with a discharge opening and a manual actuator for activating the pump means for pumping liquid from the container through the outlet means and the discharge opening. The sprayer further includes a control module having spring biased product and vent valves reciprocably disposed therein, the product and vent valves being simultaneously reciprocable by means of the manual actuator between valve open and valve closed positions. In the valve open position, the product and vent valves respectively prevent flow of product and air respectively into the liquid inlet means and into a vent passage in communication between atmosphere and an interior of the container. In the valve closed position, the product and vent valves respectively enable flow of product and air respectively into the liquid inlet means and into the vent passage.
[0011] For the sprayer described above, the product and vent valves may sealingly engage confronting internal walls in the control module to prevent flow of product and air. In a particular embodiment, the product and vent valves may each include a resilient conical section in the form of chevron seals for sealingly engaging confronting internal walls in the control module to prevent flow of product and air. The product and vent valves may be formed of a single unitary structure, or may instead be formed of a plurality of components fitted together. The product and vent valves may include a first elongated section and a second cap section fitted together. The first elongated section may include a first conical portion tapered outwardly to engage a confronting internal wall in the control module, a second elongated portion and a third elongated portion. The cap section may include a first conical portion tapered outwardly to engage another confronting internal wall in the control module, and a second elongated portion. The conical portions of the first elongated section and the second cap section may engage the confronting internal walls of the control module to prevent flow of product and air. The actuator may be depressable to first operate the pump means and thereafter activate the product and vent valves to enable flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include first and second protrusions for respectively operating a switch for engaging the motor means and thereafter operating the product and vent valves for enabling flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include a trigger lever which is normally returned to a relaxed position by a spring outwardly biasing the product and vent valves upon release of manual pressure applied to the lever. The sprayer may include electric motor means for operating the pump means, battery means for operating the motor means, and manually operable switch means for selectively operating the motor means.
[0012] The invention yet further provides a manually operated sprayer for a container of liquid to be sprayed. The sprayer includes a variable volume pump means having liquid inlet means for connecting the pump means with liquid in the container, outlet means connecting the pump means with a discharge opening and a manual actuator for activating the pump means for pumping liquid from the container through the outlet means and the discharge opening. The sprayer includes a control module having spring biased product and vent flow control means disposed therein, the product and vent flow control means being operable by means of the manual actuator between valve open and closed positions. In the valve open position, the product and vent flow control means respectively prevent flow of product and air respectively into the liquid inlet means and into a vent passage in communication between atmosphere and an interior of the container. In the valve closed position, the product and vent flow control means respectively enable flow of product and air respectively into the liquid inlet means and into the vent passage.
[0013] For the sprayer described above, the product and vent flow control means may sealingly engage confronting internal walls in the control module to prevent flow of product and air. In a particular embodiment, the product and vent flow control means may each include a resilient conical section sealingly engaging confronting internal walls in the control module to prevent flow of product and air. The product and vent flow control means may be formed of a single unitary structure, or may instead be formed of a plurality of components fitted together. The product and vent flow control means may include a first elongated section and a second cap section fitted together. The first elongated section may include a first conical portion tapered outwardly to engage a confronting internal wall in the control module, a second elongated portion and a third elongated portion. The cap section may include a first conical portion tapered outwardly to engage another confronting internal wall in the control module, and a second elongated portion. The conical portions of the first elongated section and the second cap section may engage the confronting internal walls of the control module to prevent flow of product and air. The actuator may be depressable to first operate the pump means and thereafter activate the product and vent flow control means to enable flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include first and second protrusions for respectively operating a switch for engaging the motor means and thereafter operating the product and vent flow control means for enabling flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include a trigger lever which is normally returned to a relaxed position by a spring outwardly biasing the product and vent flow control means upon release of manual pressure applied to the lever. The sprayer may include electric motor means for operating the pump means, battery means for operating the motor means, and manually operable switch means for selectively operating the motor means.
[0014] Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and together with the detail description serve to explain the principles of the invention. In the drawings:
[0016] FIG. 1 is a side elevation view of the power sprayer, partly broken away, according to the present invention;
[0017] FIG. 2 is a cross-sectional view of the power sprayer of FIG. 1 , taken substantially along line 2 - 2 in FIG. 1 , illustrating the contact arrangement for operating the power sprayer;
[0018] FIG. 3 is an exploded view of the discharge/vent control module of the power sprayer of FIG. 1 ;
[0019] FIG. 4 is an illustrative cross-sectional view of the discharge/vent control module of FIG. 3 , taken substantially along line 4 , 5 - 4 , 5 in FIG. 3 , illustrating a product valve and an identical vent valve in a closed position; and
[0020] FIG. 5 is similar to FIG. 4 showing the product valve and the identical vent valve in an open position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring now to the drawings wherein like reference numerals designate corresponding parts throughout the several views, FIGS. 1-5 illustrate a battery operated power sprayer according to the present invention, generally designated power sprayer 10 .
[0022] Before proceeding with the detailed description of power sprayer 10 , those skilled in the art will appreciate in view of this disclosure that the components and features of sprayer 10 discussed herein may be applicable for use with a manual pumping type sprayer (not shown) or for use with the battery activated type sprayer as shown in FIG. 1 .
[0023] Referring to FIG. 1 , power sprayer 10 of the present invention is shown as having coupled thereto a container closure 12 for mounting the sprayer to a container 14 of liquid product to be sprayed. Power sprayer 10 may generally include housing 16 made of a suitable plastic material, for example, and having enclosed therein pump system 18 , container vent and product discharge control module 20 (hereinafter “control module 20 ”) and power unit 22 .
[0024] As shown in FIG. 1 , power sprayer 10 may have hingedly mounted thereto as at 24 an actuator which may comprise a trigger lever 26 for actuating sprayer 10 . Housing 16 may include a discharge nozzle cap 28 affixed thereon and including a discharge orifice (not shown) formed therein at the terminal end of discharge tube 30 of the sprayer. Discharge tube 30 may be operatively connected to pump 32 of pump system 18 for discharging product from container 14 under pressure as needed. Pump 32 may include a variable volume pump chamber (not shown) into which an inlet passage extends. Product outlet tube 34 may be operatively connected at one end thereof to the inlet passage of pump 32 , and to product side 36 of control module 20 at the other end thereof. A vent inlet tube 38 may include one end thereof operatively connected to vent side 40 of control module 20 , and the other end thereof connected to an opening 41 adjacent the discharge orifice of discharge nozzle cap 28 for venting container 14 during use. Pump 32 may be operated by an electric motor (not shown) disposed behind pump 32 via gearing and cams in a manner similar to that disclosed in U.S. Pat. No. 5,716,007, the disclosure of which is incorporated herein by reference. A pair of batteries (not shown) may be housed within suitable compartments of the sprayer in power unit 22 , and may be insertable from the rear end of sprayer 10 . A battery cover 42 may be used to cover the batteries and may be snap-fitted in place onto power sprayer 10 , as shown in the closed configuration of FIG. 1 .
[0025] Referring to FIG. 2 , a metal spring leg 44 may be mounted to the sprayer such that when depressed by means of arms 46 of trigger lever 26 , a depressable on/off switch 48 energizes control mechanism 47 for allowing current to flow to the motor for pump system 18 for operating pump 32 . Upon the release of trigger lever 26 , outwardly biased spring leg 44 releases switch 48 to its off position so as to shut off the motor for pump system 18 and thereby prevent product from being discharged out through the orifice of discharge nozzle cap 28 . It would be apparent to those skilled in the art in view of this disclosure that instead of depressable on/off switch 48 , other arrangements, such as a metal contact spring leg 44 directly contacting a battery metal contact to close an electrical circuit upon being depressed by means of arms 46 of trigger lever 26 , could be utilized for allowing current to flow to the motor for pump system 18 for operating pump 32 .
[0026] As shown in FIGS. 1 and 2 , in addition to arms 46 , trigger lever 26 may include projections 50 in contact with product and vent valves 52 , 54 for controlling the operation thereof. In the embodiment shown, arms 46 and projections 50 may be configured such that by manually depressing trigger lever 26 , arms 46 initially press spring leg 44 to engage switch 48 , and thereafter, projections 50 simultaneously engage product and vent valves 52 , 54 to press valves 52 , 54 to allow product and air to pass via valves 52 , 54 after a slight delay.
[0027] Referring to FIGS. 1 and 3 - 5 , the configuration and operation of control module 20 will next be described in detail.
[0028] Specifically, as shown in FIG. 3 , product and vent valves 52 , 54 , respectively, of control module 20 may be respectively housed in product and vent housings 56 , 58 , and biased outwardly by means of springs 60 . Product and vent valves 52 , 54 may be formed of a two-piece structure including caps 62 assembled onto elongated valve sections 64 , 66 for ease of manufacture, but may be manufactured of a one piece structure as would be apparent to those skilled in the art.
[0029] Referring next to FIGS. 4 and 5 , which respectively illustrate cross-sectional views of the module of FIG. 3 , taken along lines 4 - 4 and 5 - 5 in FIG. 3 , product valve 52 is illustrated in closed and opened positions respectively. It is to be understood that the layout and operation of vent valve 54 and vent housing 58 are identical to that of product valve 52 and product housing 56 . Accordingly, the description hereinafter of product valve 52 and product housing 56 will likewise apply identically to vent valve 54 and vent housing 58 .
[0030] Specifically, as shown in FIGS. 3 and 4 , product and vent valves 52 , 54 , may each include fixedly connected first and second sections designated as elongated valve section 64 and cap 62 . Elongated valve section 64 may include a first conical portion 68 , a second elongated portion 70 , and a third elongated portion 72 having a reduced diameter cross-section as compared to portion 70 . Elongated portions 70 , 72 may be formed of a uniform cross-section along the central longitudinal axis of valve 52 . Elongated portion 72 may be dimensioned to fit within the cavity in cap 62 , as shown in FIG. 4 . Cap 62 may include a conical portion 74 and an elongated portion 76 formed of a uniform cross-section along the central longitudinal axis of cap 62 . For assembly, elongated valve section 64 and cap 62 may be fitted together as shown in FIG. 4 and retained in the configuration of FIG. 4 by means of friction or other such means known in the art. Conical portions 68 and 74 of elongated valve section 64 and cap 62 , respectively, may include a tapered internal configuration to define resilient seal members 78 , 80 as shown in FIG. 4 . When fitted within product housing 56 , resilient seal members 78 , 80 sealingly engage the confronting walls of housing 56 to form a seal. Likewise, when fitted within vent housing 58 , resilient seal members 78 , 80 sealingly engage the confronting walls of housing 58 to form a seal.
[0031] Referring to FIG. 4 , product housing 56 may generally include outlet end 82 having product outlet tube 34 connected thereon and inlet end 84 having product inlet tube 86 connected thereon. Product inlet tube 86 may be connected to a dip tube 88 disposed in container 14 through container closure 12 . Likewise, vent housing 58 may generally include outlet end 85 having vent outlet tube 100 connected thereon and inlet end 98 having vent inlet tube 38 connected thereon. In the particular embodiment shown, housing 56 may include first through fourth cross sectional areas 90 , 92 , 94 and 96 , respectively. Areas 90 and 94 may include a generally uniform cross-section along the central longitudinal axis of housing 56 , whereas areas 92 and 96 may be tapered inwardly and outwardly, respectively, as shown in FIGS. 4 and 5 . It would be apparent to those skilled in the art that the specific cross-sectional configurations shown for housings 56 and 58 are for illustrative purposes only, and are not intended to limit the scope of the present invention to the specific embodiment shown.
[0032] Once fitted within housing 56 , as shown in FIG. 4 , resilient members 78 , 80 of product valve 52 may be respectively disposed in engagement with areas 94 and 90 of housing 56 for sealing product valve 52 in a closed, at-rest position. Likewise, once fitted within housing 58 , as shown in FIG. 4 , resilient members 78 , 80 of vent valve 54 may be respectively disposed in engagement with areas 94 and 90 of housing 58 for sealing vent valve 54 in a closed, at-rest position. When trigger lever 26 is pressed to operate pump system 18 by means of the engagement of spring leg 44 and switch 48 , as briefly discussed above and as shown in FIG. 5 , protrusions 50 of trigger lever 26 simultaneously move product and vent valves 52 , 54 inwards within housings 56 , 58 , respectively. In the FIG. 5 position of product valve 52 , the inlet to the pump is valved open such that product within container 14 may be suctioned in through inlet end 84 in the direction of arrow-P 1 , around the outer circumference of portions 68 and 70 of valve 52 , and out through outlet end 82 in the direction of arrow-P 2 to then be fed into product outlet tube 34 , and out through discharge tube 30 via pump 32 . Likewise, in the FIG. 5 position of vent valve 54 , the air vent is opened such that air may be suctioned in through opening 41 ( FIG. 1 ) and then through inlet end 98 in the direction of arrow-A 1 , around the outer circumference of portions 68 and 70 of valve 54 , and out through outlet end 85 in the direction of arrow-A 2 to then be fed into vent outlet tube 100 into container 14 . Upon the release of trigger lever 26 , product and vent valves 52 , 54 return to their rest position shown in FIG. 4 under the bias of spring 60 .
[0033] As discussed above, various modifications may be made to power sprayer 10 without departing from the scope of the present invention. For example, seal rings or other such means may be used instead of resilient members 78 and 80 on valves 52 , 54 for sealing the respective inlet and outlet ends of the valves from air or product as needed. Moreover, instead of the axially reciprocable vent valves 52 , 54 illustrated, flap valves may be provided within control module 20 and be operable by trigger lever 26 to control flow of air and product as needed.
[0034] Although particular embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those particular embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims. | A manually operated sprayer for a container of liquid to be sprayed includes variable volume pump means having liquid inlet and outlet means for discharging the contents of the container. The sprayer further includes a control module having product and vent valves reciprocably disposed therein, the product and vent valves being simultaneously reciprocable by means of the manual actuator between valve open and valve closed positions. In the valve open position, the product and vent valves respectively prevent flow of product and air respectively into the liquid inlet means and into a vent passage in communication between atmosphere and an interior of the container, and in the vent closed position, the product and vent valves respectively enable flow of product and air respectively into the liquid inlet means and into the vent passage. | 1 |
CLAIM OF PRIORITY/INCORPORATION BY REFERENCE
This application is a U.S. national stage entry under 35 U.S.C. §371 from PCT International Application No. PCT/US2011/027012, filed Mar. 3, 2011, which claims priority to and the benefit of the filing date of U.S. Provisional Application No. 61/314,959, filed Mar. 17, 2010, to both of which this application claims the benefit of priority, and the entirety of the subject matter of both of which is incorporated herein by reference.
FIELD OF THE INVENTION
The present disclosure relates to paint including hydrophobized minerals and related methods. In particular, the present disclosure relates to water-based paint including minerals that have been treated with one or more hydrophobizing agents, and related methods.
BACKGROUND OF THE INVENTION
Paint typically includes one or more pigments, binders, and solvents. Pigments typically include granular solids and/or minerals incorporated into the paint to contribute color, toughness, texture, and/or to act as an extender. Binders are film-forming components of paint, which impart adhesion, bind the pigments together, and may strongly influence properties such as, for example, gloss potential, exterior durability, flexibility, and toughness. Binders typically include synthetic or natural resins, such as, for example, polymers and copolymers based on acrylics, polyurethanes, polyesters, melamine resins, epoxies, and/or oils or other monomeric species. Solvents are considered to be the liquid(s) used in paint, which suspend the pigments and binders, and transport them from a paint applicator to a surface being painted. Once on the surface being painted, the solvent evaporates through drying and/or curing and leaves behind a dry paint film on the painted surface. Water-based paint includes water and dispersing chemicals as solvent rather than mineral spirits or other organic solvents. Water-based paint is often used in commercial and residential applications.
Two characteristics of paint that are often desirable are abrasion resistance, which is often measured as scrub resistance and stain resistance. Scrub resistance relates to the ability to clean a dry paint film without significantly altering the characteristics of the painted finish, for example, by eroding the surface of the dry paint film. Stain resistance relates to the resistance of a dry paint film to be stained in a manner in which the stain cannot be cleaned from the film. These two characteristics are desirable for many common paint uses, such as interior and exterior paint for commercial and residential applications, where it may often be more desirable to clean a painted surface than to repaint the surface.
Thus, it may be desirable to provide compositions for use in paint that improve scrub resistance and/or stain resistance of paint. Further, it may be desirable to provide pigments for use in water-based paint that improve scrub resistance and/or stain resistance in a cost-effective manner.
SUMMARY OF THE INVENTION
In the following description, certain aspects and embodiments will become evident. It should be understood that the aspects and embodiments, in their broadest sense, could be practiced without having one or more features of these aspects and embodiments. Thus, it should be understood that these aspects and embodiments are merely exemplary.
One aspect of the disclosure relates to a water-based paint composition. The composition may include at least one mineral treated with at least one hydrophobizing agent. The paint may include, for example, latex paint. The at least one mineral may include at least one of clay, kaolin, mica, titanium dioxide, talc, natural or synthetic silica or silicates, feldspars, nepheline syenite, wollastonite, diatomite, barite, glass (e.g., cullet), and calcium carbonate. For example, the at least one mineral may include kaolin, such as, for example, at least one of hydrous kaolin, metakaolin, and calcined kaolin. According to some aspects, the at least one mineral may include calcium carbonate, such as, for example, at least one of ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC).
According to some aspects, the at least one hydrophobizing agent may include at least one of fatty acids, fatty amines, and silanes. For example, fatty acids may include one or more of aliphatic carboxylic acids having from ten to thirty carbon atoms in their chain, including but not limited to, stearic acid, behenic acid, palmitic acid, arachidic acid, montanic acid, capric acid, lauric acid, myristic acid, isostearic acid, cerotic acid, and mixtures thereof. For example, the at least one hydrophobizing agent may include fatty acid, such as, for example, stearic acid. In another example, the hydrophobizing agent may include a fatty amine, such as, for example, a fatty amine carbohydrate complex.
According to a further aspect, a method of making water-based paint may include treating at least one mineral with a hydrophobizing agent, and combining the at least one treated mineral with a binder.
According to still a further aspect, a water-based paint composition may include at least one mineral treated with at least one hydrophobizing agent and at least one particulate TiO 2 pigment. A film formed from the water-based paint composition may have a contrast ratio at least about 0.1% higher than a similar water-based paint composition wherein the at least one mineral treated with at least one hydrophobizing agent is replaced with an equal volume of said particulate TiO 2 pigment.
Additional objects and advantages of the disclosure will be set forth in part in the description which follows, or may be learned by practice of the disclosed embodiments.
Aside from the arrangements set forth above, the embodiments could include a number of other arrangements, such as those explained hereinafter. It is to be understood that both the foregoing description and the following description are exemplary only.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this description, illustrate several exemplary embodiments and together with the description, serve to explain the principles of the embodiments. In the drawings,
FIG. 1 shows a side-by-side comparison of scrub test results for a water-based paint formulation including untreated calcium carbonate, and the water-based paint formulation including calcium carbonate treated with an exemplary hydrophobizing agent;
FIG. 2 shows a side-by-side comparison of scrub test results for a water-based paint formulation including untreated calcium carbonate, and the water-based paint formulation including calcium carbonate treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cured at room temperature;
FIG. 3 shows a side-by-side comparison of scrub test results for a water-based paint formulation including untreated calcined kaolin, and the water-based paint formulation including calcined kaolin composition treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cured at room temperature;
FIG. 4 shows a side-by-side comparison of scrub test results for a water-based paint formulation including an untreated calcined kaolin and calcium carbonate, and the water-based paint formulation including calcined kaolin and calcium carbonate compositions treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cured at room temperature;
FIG. 5 shows a side-by-side comparison of scrub test results for a water-based paint formulation including untreated calcium carbonate, and the water-based paint formulation including calcium carbonate composition treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cold-cured;
FIG. 6 shows a side-by-side comparison of scrub test results for a water-based paint formulation including untreated calcined kaolin, and the water-based paint formulation including calcined kaolin composition treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cold-cured; and
FIG. 7 shows a side-by-side comparison of scrub test results for a water-based paint formulation including untreated calcined kaolin and calcium carbonate, and the water-based paint formulation including calcined kaolin and calcium carbonate compositions, both treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cold-cured.
FIG. 8 shows a side-by-side comparison of stain resistance test results for a water-based paint formulation including untreated calcined kaolin and calcium carbonate, and the water-based paint formulation including calcined kaolin and calcium carbonate compositions, both treated with the exemplary hydrophobizing agent, with both water-based paint formulations being cold-cured.
FIG. 9 is a graph of opacity vs. amount of TiO 2 content for several paint samples prepared with different pigments, including pigments comprising coated and uncoated calcium carbonate.
FIG. 10 a graph of opacity vs. amount of TiO 2 content for several paint samples prepared with different pigments, including pigments comprising coated calcium carbonate and pigments comprising uncoated hydrous kaolin.
FIG. 11 a graph of tint strength vs. amount of TiO 2 content for several paint samples prepared with different pigments.
FIG. 12 shows scrub test results for paint samples comprising different pigments.
FIG. 13 is a graph of contrast ratio vs. TiO 2 replacement level for several paint formulations.
FIG. 14 is a graph of contrast ratio vs. TiO 2 level for pigments including untreated and treated ground calcium carbonate.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
Reference will now be made in more detail to a number of exemplary embodiments of the invention.
In one aspect, the disclosure relates to paint, including at least one mineral treated with a hydrophobizing agent. For example, the paint may include water-based paint, and the at least one mineral may include at least one of clay, kaolin, mica, and calcium carbonate. For example, the paint may be latex paint, and the at least one mineral may include kaolin, such as, for example, at least one of hydrous kaolin and calcined kaolin. According to some embodiments, the at least one mineral may include calcium carbonate, such as, for example, at least one of granulated calcium carbonate (GCC) and precipitated calcium carbonate (PCC). According to some embodiments, the at least one hydrophobizing agent may include at least one of fatty acids, fatty amines, and silanes. For example, fatty acids may include one or more of aliphatic carboxylic acids having from ten to thirty carbon atoms in their chain, including but not limited to, stearic acid, behenic acid, palmitic acid, arachidic acid, montanic acid, capric acid, lauric acid, myristic acid, isostearic acid, cerotic acid, and mixtures thereof. For example, the at least one hydrophobizing agent may include fatty acid, such as, for example, stearic acid. In another example, the at least one hydrophobizing agent may include a fatty amine, such as, for example, a fatty amine carbohydrate complex.
According to some embodiments, hydrophobizing agents may be chosen from metal stearates, ammonium stearate, titanate coupling agents, silicones and organo-silicones, organo-silanes, fluorocarbons, fatty acid amines and amides, quaternary amine compounds, hydrocarbon oils, hydrocarbon waxes, hydrocarbon resins, zirconium compounds, maleic anhydride, maleic anhydride grafted polymers (e.g., modified polyethylene and/or polypropylene), carboxylated polybutadiene, and organometallic compounds.
In some embodiments, the mineral may be treated with 0.1% to 10% by weight of the hydrophobizing agent, such as, for example, from 1% to 5% by weight hydrophobizing agent.
It has been found that contrary to conventional wisdom, treating minerals for use in water-based paint with hydrophobizing agents may result in improved scrub resistance and/or stain resistance of the dry paint film. Conventional wisdom would suggest that treating minerals for use in water-based paints with hydrophobizing agents would lead to unacceptable results because, for example, the treated minerals would be hydrophobic and would thus not be compatible with the water solvent of water-based paint. For example, some minerals treated with hydrophobizing agents float on top of water-based paint, thus leading one to believe that including the treated minerals in water-based paints would lead to undesirable characteristics. In contrast to conventional wisdom, however, it has been found that treating minerals for water-based paints with hydrophobizing agents may result in improved scrub resistance and/or stain resistance of dry paint films of water-based paints.
According to some embodiments, the minerals may include kaolin, for example, a calcined kaolin having a mean particle size (d 50 ) of about 1.5 microns, such as a calcined kaolin product marketed under the trademark GLOMAX LL by IMERYS. According to some embodiments, the minerals may include calcium carbonate, for example, a ground calcium carbonate product marketed under the trademark #10 WHITE by IMERYS.
Ground calcium carbonate may include ground, naturally occurring calcium carbonate from limestone sources, such as, for example, marble, limestone, dolomite, chalk, and “reef limestone”. According to some embodiments, the minerals may include precipitated calcium carbonate. Precipitated calcium carbonate may be generally prepared by a process in which calcium carbonate is calcined to produce calcium oxide, or “quicklime.” The quicklime is thereafter “slaked” with water to produce an aqueous slurry of calcium hydroxide, and finally, the calcium hydroxide is carbonated with a carbon-dioxide-containing gas to produce precipitated calcium carbonate, which may be subsequently processed by further grinding and drying to produce a dry powder form.
Number 10 WHITE, also known as #10 WHITE, is an example of a white, ground calcium carbonate from a marble source with an average particle size of 12 microns and 325 mesh residue of approximately 0.5%. Other ground calcium carbonates may be produced by wet grinding or dry grinding and may have an average particle diameter between 0.3 microns and 25 microns or more preferably between 1 micron and 12 microns measured by Sedigraph method.
GLOMAX LL is an example of a conventional white calcined clay with an average particle size, by Sedigraph method, of 1.4 microns. However, other calcined clays may also be used, for example, calcined clays manufactured by either soak-calcination or flash calcination at temperatures above 600 degrees Celsius with average particle sizes from 0.2 microns to 15 microns, such as for example from 0.6 microns to 5.0 microns, and with oil absorptions from 40 g/100 g to 135 g/100 g by spatula rub-out method.
According to some embodiments, paints disclosed herein may include for example, architectural paints, such as textured decorative paints, including, for example, aggregated calcium carbonate. According to some embodiments, paints disclosed herein may have desirable optical properties, such as, for example, dry paint films having a low sheen and high opacity.
According to some embodiments, dry paint film produced from the exemplary paints disclosed herein may exhibit specified properties of color. For example, components L, a, and b are color component values of a 3-dimensional color space scale, which may be measured by, for example, a Hunter Ultrascan XE instrument. On the color space scale, “L” is a measure of Whiteness, “+a” is a measure of Redness, “−a” is a measure of Greenness, “+b” is a measure of Yellowness, “−b” is a measure of Blueness. Whiteness (YI) can be measured according to the ASTM-E-313 standard method. It is to be appreciated that the relative color of paint can be “lighter” (e.g., appearing less blue) or “darker” (e.g., appearing more blue). In the case of tint strength, “lighter” colored paint (i.e., paint having a higher L value) is considered to have the higher tint strength after addition of a darker pigment.
Another optical property of dry paint film is referred to as “457 brightness,” which can be measured using a standard method, such as, for example, by using ASTM D 985-97. The 457 brightness property is a measure of the directional reflectance of a surface at a wavelength of 457 nanometers.
Yet a further optical property of dry paint film is opacity, also known as contrast ratio. Dry paint film opacity is related to light scattering and light absorption, which may occur when light travels through two or more different materials, as different materials typically have different refractive indices. In a pigmented paint, light may be scattered by both the pigment and extender, as well as cavities or voids and may also be absorbed by the pigment system. Thus, to maximize opacity, it is generally desirable to maximize light scattering by the pigment/extender and voids or cavities and/or by absorption of light by absorbent species.
The exemplary paints disclosed herein may also include at least one additive chosen from conventional additives, such as, for example, pigments other than the mineral-based pigments disclosed herein, surfactants, thickeners, defoamers, wetting agents, dispersants, solvents, and coalescents, as well as other functional additives. Exemplary paints include textured paints, latex paints, and acrylic paints.
According to some embodiments, the paint may have a pigment volume concentration (PVC) ranging from, for example, about 5% to about 90%, from about 40% to about 70%, or from about 40% to about 50%. According to some embodiments, the paint may have a pigment volume concentration ranging from, for example, about 50% to about 60%, or from about 60% to about 70%. In other embodiments, the paint has a pigment volume concentration of at least about 70%, such as, from about 70% to about 85%. As used herein, “pigment volume concentration” (PVC) is defined according to the following equation:
PVC
=
volume
of
pigments
volume
of
pigments
+
volume
of
binder
.
The present disclosure is further illustrated by the following non-limiting examples, which are intended to be purely exemplary of the invention. In the examples shown below, the following abbreviations are used:
EXAMPLES
Preparation of Examples
Seven pairs of test samples were prepared for comparison according to the standard mixing procedure now described. A Cowles high speed mixer was used having a dispersion blade running with a tip speed of approximately 2500 ft/minute. A mill base was prepared by incorporation of the pigments into a dispersion consisting of dispersant, stabilizer, and defoamer additives in water. This was mixed until a Hegman value of 4 (or other acceptable measure of dispersion) was achieved, when thickener was added and run until a stable vortex was formed. At this point the mixer speed was reduced and the latex added, followed finally by coalescent chemicals.
Samples of the mineral were hydrophobized where indicated, by coating the dry mineral with hydrophobizing agent by blending in a Waring blender. Prior to addition to the blender, the hydrophobizing agent was heated to a temperature in excess of its melting point (e.g., 95 degrees C.).
Example 1
In a first test pair, a first water-based paint formulation (Sample 1) was prepared by incorporating untreated ground calcium carbonate (#10 White), and untreated calcined kaolin (GLOMAX LL), into a standard 65% PVC formulation shown below in Table I. A second water-based paint formulation (Sample 2) was prepared that was the same as the first paint formulation of this example, except that the calcium carbonate composition was hydrophobized by treating it with 2.5% by weigh in comparison to the mineral of the hydrophobizing agent. In all present examples, the hydrophobizing agent used was a fatty amine carboxylate complex (RAYBO 57 Optisperse HS, available from Raybo Chemical Company, Huntington W. Va., US).
The hydrophobizing agent was reacted with the calcium carbonate while mixing at a temperature above 70 degrees Celsius in order to melt the fatty amine carboxylate complex and to cause it to coat surfaces of the calcium carbonate particles.
The ratio of hydrophobizing agent-to-calcium carbonate can be adjusted based on the surface area of the calcium carbonate. However, it is \desirable to achieve monolayer coverage of the surface, although lower or higher addition levels may be satisfactory. For ground calcium carbonates coated with fatty amine carboxylate complex, this ratio can be between 0.2-to-99.8 and 4.0-to-96.0, and is more typically 1.0-to-99.0.
Table I below provides a listing of the components of the exemplary paint formulations of Example 1. The following list is a legend for the abbreviations listed in Table I:
KTPP is potassium tripolyphosphate
TAMOL 731=is a surfactant or wetting agent, which includes a sodium salt of polycarboxylated condensed naphthalene, which may be available from Rohm and Haas Company.
IGEPAL CO-610 is an Ethoxylated Nonyl Phenol, which may be available from Rhodia, Inc.
COLLOIDS 681F (now Rhodoline 681F) is a liquid defoamer, which may be available from Rhodia, Inc.
TiO 2 (R-706) is a rutile titanium oxide pigment, which may be available from DuPont.
#10 WHITE is a ground calcium carbonate product available from IMERYS.
GLOMAX LL is a calcined kaolin product available from IMERYS.
NATROSOL PLUS is a hydrophobically-modified hydroxyethylcellulose (HMHEC) thickener, which may be available from Hercules Inc.
UCAR 379 is a Latex Vinyl Acrylic copolymer, which may be available from The Dow Chemical Company.
TEXANOL is an ester alcohol-based coalescent, which may be available from Eastman Kodak Company. The chemical formula for TEXANOL is 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.
TABLE I
MATERIAL
GALLONS
LBS
TOTAL
WATER
41.65
346.91
29.05%
KTPP
0.09
1.80
0.15%
TAMOL 731
0.87
8.00
0.67%
IGEPAL CO-610
0.46
4.00
0.33%
COLLOIDS 681F
0.41
3.00
0.25%
TiO 2 (R-706)
2.45
81.67
6.84%
#10 WHITE
11.24
252.99
21.19%
GLOMAX LL
9.12
199.91
16.74%
NATROSOL PLUS
0.43
3.94
0.33%
High speed disperse
UCAR 379 Latex
23.70
210.96
17.67%
ETHYLENE GLYCOL
2.69
24.99
2.09%
TEXANOL
1.36
10.00
0.84%
WATER
5.52
45.98
3.85%
TOTAL PAINT
100.00
1194.14
100.00%
The dry film properties of the two water-based paint formulations in Example 1 are shown in Table II below.
TABLE II
PROPERTIES
65% PVC
SAMPLE 1
SAMPLE 2
60 Deg Gloss
2.8
2.7
85 Deg Sheen
2.8
2.6
L
95.37
94.74
a
−0.84
−0.90
b
1.91
2.11
Opacity (Y)
94.57
94.52
WI E313(2/C)
82.15
79.95
YI E313(2/C)
3.06
3.44
457 Brightness
88.81
87.35
WI is Whiteness Index according to ASTM E313 (2/C) and YI is Yellowness Index to ASTM E313 (2/C). As shown in Table II, there is very little change in the listed properties of the dry paint film for the first formulation, which does not include minerals treated with a hydrophobizing agent, relative to the second formulation, which includes minerals treated with a hydrophobizing agent. However, as explained below, the second formulation exhibits improved scrub resistance.
Following preparation of the two paint formulations, a scrub test was performed on both to determine whether one of the two formulations had a higher scrub resistance. The scrub test used is described in ASTM D2486 Method B, which describes a method for side by side comparison of the abrasion resistance of two paint films, which are prepared simultaneously on the same test sheet. According to the scrub test, a coating of paint having a predetermined thickness is applied to a sample card having a surface color that contrasts with the color of the applied paint sample. The paint is allowed to dry and may be cured under predetermined conditions, such that a dry paint film of the paint sample is obtained. An abrasive material is rubbed across the dry paint film using a reciprocating brush according to controlled procedures. The amount of the surface of the sample card showing through the dry paint film following the rubbing of the abrasive material provides an indication of the scrub resistance of the paint being tested. In particular, a paint that reveals less of the surface of the sample card than another paint to which the first paint is being compared, has a greater scrub resistance. As shown in FIGS. 1-7 , the sample card showing less of the darker color (i.e., the color of the surface of the sample card prior to application of the paint sample) has a higher scrub resistance.
FIG. 1 shows a side-by-side comparison of scrub test results for the first paint formulation of Example 1 on the left and for the second paint formulation on the right. As can be seen from FIG. 1 , the second paint formulation, in particular, the paint formulation which included the calcium carbonate treated with the exemplary hydrophobizing agent, reveals less of the surface of the sample card. Thus, the second paint formulation of Example 1 exhibits improved scrub resistance relative to the first formulation, which includes the untreated calcium carbonate.
Example 2
In a second test pair, a first water-based paint formulation was prepared by incorporating untreated calcium carbonate into the low volatile organic content (VOC) 65% PVC formulation shown below in Table III. A second water-based paint formulation was prepared that was the same as the first paint formulation of this example, except that the calcium carbonate was treated with Raybo 57 hydrophobizing agent prior to incorporation into the paint composition. Both the first and the second paint formulations were cured at room temperature.
TABLE III
MATERIAL
GALLONS
LBS
TOTAL
WATER
41.6
346.9
29.1%
KTPP
0.1
1.8
0.2%
TAMOL 731
0.9
8.0
0.7%
IGEPAL CO-610
0.5
4.0
0.3%
COLLOIDS 681F
0.4
3.0
0.3%
TiO 2 (R-706)
2.5
81.7
6.8%
#10 WHITE
11.2
253.0
21.2%
GLOMAX LL
9.1
199.9
16.8%
NATROSOL PLUS
0.4
3.9
0.3%
High speed disperse
ECOVAE 401 LATEX
23.7
211.0
17.7%
WATER
9.6
79.7
6.7%
TOTAL PAINT
100.00
1192.91
100.00%
FIG. 2 shows a side-by-side comparison of scrub test results for the first paint formulation of this example on the left and for the second paint formulation on the right. As can be seen from FIG. 2 , the second paint formulation, including the calcium carbonate mineral treated with the exemplary hydrophobizing agent, exhibits improved scrub resistance.
Example 3
In a third test pair, a first water-based paint formulation was prepared by incorporating untreated calcined kaolin into the low VOC 65% PVC formulation shown in Table III. A second water-based paint formulation was prepared that was the same as first paint formulation of this example, except that the calcined kaolin composition was treated with Raybo 57 hydrophobizing agent prior to incorporation into the paint formulation, such that the calcined kaolin particles were coated with hydrophobizing agent. Both the first and the second paint formulations were cured at room temperature.
FIG. 3 shows a side-by-side comparison of scrub test results for the first paint formulation of this example on the left and for the second paint formulation on the right. As can be seen from FIG. 3 , the second paint formulation, including the calcined kaolin composition treated with the exemplary hydrophobizing agent, exhibits improved scrub resistance.
Example 4
In a fourth test pair, a first water-based paint formulation was prepared by incorporating untreated calcined kaolin and untreated calcium carbonate into the low VOC 65% PVC formulation shown in Table III. A second water-based paint formulation was prepared that was the same as the first paint formulation of this example, except that the calcined kaolin and calcium carbonate compositions were treated with Raybo 57 hydrophobizing agent prior to incorporation into the paint formulation, such that the calcined kaolin particles and the calcium carbonate particles were treated with hydrophobizing agent. Both the first and the second paint formulations were cured at room temperature.
FIG. 4 shows a side-by-side comparison of scrub test results for the first paint formulation of this example on the left and for the second paint formulation on the right. As can be seen from FIG. 4 , the second paint formulation, including the minerals treated with the exemplary hydrophobizing agent, exhibits improved scrub resistance.
Example 5
In a fifth test pair, a first water-based paint formulation was prepared by incorporating untreated calcium carbonate into the low VOC 65% PVC formulation shown in Table III. The low VOC formulation uses a commercially available latex polymer, which does not require the use of coalescent agents. A second water-based paint formulation was prepared that was the same as the first paint formulation of this example, except that the calcium carbonate composition was treated with Raybo 57 hydrophobizing agent prior to incorporation into the paint formulation, such that the calcium carbonate particles of the calcium carbonate composition were coated with hydrophobizing agent. Both the first and the second paint formulations were cold-cured. Cold curing was undertaken by placing the freshly prepared paint film in an environmental chamber at 9 degrees Celsius for 24 hours to simulate application of paint in winter conditions.
FIG. 5 shows a side-by-side comparison of scrub test results for the first paint formulation of this example on the left and for the second paint formulation on the right. As can be seen from FIG. 5 , the second paint formulation, including the mineral treated with the exemplary hydrophobizing agent, exhibits improved scrub resistance.
Example 6
In a sixth test pair, a first water-based paint formulation was prepared by incorporating untreated calcined kaolin into the low VOC 65% PVC formulation shown in Table III. A second water-based paint formulation was prepared that was the same as the first paint formulation of this example, except that the calcined kaolin composition was treated with Raybo 57 hydrophobizing agent prior to incorporation into the paint formulation. Both the first and the second paint formulations were cold-cured.
FIG. 6 shows a side-by-side comparison of scrub test results for the first paint formulation of this example on the left and for the second paint formulation on the right. As can be seen from FIG. 6 , the second paint formulation, including the mineral treated with the exemplary hydrophobizing agent, exhibits improved scrub resistance.
Example 7
In a seventh test pair, a first water-based paint formulation was prepared by incorporating untreated calcined kaolin and untreated calcium carbonate into the low VOC 65% PVC formulation shown in Table III. A second water-based paint formulation was prepared that was the same as the first paint formulation of this example, except that the calcined kaolin and calcium carbonate compositions were treated with Raybo 57 hydrophobizing agent prior to incorporation into the paint formulation, such that the calcined kaolin particles and the calcium carbonate particles were coated with hydrophobizing agent. Both the first and the second paint formulations were cold-cured at 9 degrees Celsius.
FIG. 7 shows a side-by-side comparison of scrub test results for first paint formulation of this example on the left and for the second paint formulation on the right. As can be seen from FIG. 7 , the second paint formulation, including the minerals treated with the exemplary hydrophobizing agent, exhibits improved scrub resistance.
As shown by Examples 1-7, treating minerals such as kaolin and calcium carbonate with a hydrophobizing agent results in improved scrub resistance for water-based paints. Both the treated calcium carbonate minerals and the treated calcined kaolin minerals exhibited improved scrub resistance relative to corresponding untreated minerals. Further, treated minerals improved scrub resistance, regardless of the method of curing the paint. Thus, although rendering the minerals hydrophobic by such treatment would not be expected to provide acceptable results with water-based paints, the test results indicate that incorporating hydrophobic minerals into water-based paint results in improved scrub resistance.
The dry film properties of four exemplary water-based paint formulations are shown in Table IV below. In particular, the dry film properties are shown for:
(1) a first paint formulation incorporating untreated calcined kaolin and untreated calcium carbonate into the low VOC 65% PVC formulation shown in Table III;
(2) a second paint formulation incorporating untreated calcined kaolin and treated calcium carbonate composition into the low VOC 65% PVC formulation shown in Table III;
(3) a third paint formulation incorporating untreated calcium carbonate and treated calcined kaolin composition into the low VOC 65% PVC formulation shown in Table III; and
(4) a fourth paint formulation incorporating treated calcium carbonate composition and treated calcined kaolin composition into the low VOC 65% PVC formulation shown in Table III.
TABLE IV
Sample 1
Sample 2
Sample 3
Sample 4
Coated #10
no
yes
no
yes
Coated Glomax LL
no
no
yes
yes
60 Deg Gloss
2.9
2.8
2.7
2.8
85 Deg Sheen
2.6
2.6
2.3
2.3
L
94.83
94.77
93.89
93.61
a
−0.67
−0.73
−0.77
−0.81
b
1.80
2.15
2.71
2.67
Opacity (Y)
93.70
92.68
92.12
91.80
WI E313(2/C)
81.58
79.83
75.44
75.06
YI E313(2/C)
3.01
3.64
4.74
4.65
457 Brightness
87.92
87.33
84.98
84.51
Similar to Table II above, Table IV shows that there is very little change in the properties of the dry paint film shown in Table IV for the formulations that do not include minerals treated with a hydrophobizing agent, relative to the formulations that include minerals treated with a hydrophobizing agent. However, as explained above, the treated formulations exhibit improved scrub resistance.
Example 8
In an eighth test pair, a first water-based paint formulation was prepared by incorporating untreated calcined kaolin and untreated calcium carbonate into the low VOC 65% PVC formulation shown in Table III. A second water-based paint formulation was prepared that was the same as the first paint formulation of this example, except that the calcined kaolin and calcium carbonate compositions were treated with 2.5% by weight Raybo 57 hydrophobizing agent prior to incorporation into the paint formulation. Both the first and the second paint formulations were cold-cured at 9 degrees Celsius.
Following preparation of the two paint formulations, a stain resistance test was performed on both to determine whether one of the two formulations had a higher stain resistance. In the stain resistance test, a coating of paint approximately 3 mils thick is applied to a sample card having a surface color that contrasts with the color of the applied paint sample. The paint is allowed to dry for at least 24 hours to obtain a dry paint film of the paint sample. Various staining agents (i.e., oil, mustard, red wine, and ink) were then applied to the film and allowed to stand for 30 seconds to 1 minute, unless otherwise noted. The excess staining agent was then wiped off with a dry paper towel. All of the samples with the exception of the ink were then cleaned with a standardized non-abrasive scrub media in conformance with ASTM Method D3450. The ink sample was cleaned by using a paper towel soaked in mineral spirits to wipe off the remaining staining agent. The films were then dried by wiping with a dry paper towel.
FIG. 8 shows a side-by-side comparison of stain resistance test results for the first paint formulation of this example on the left and for the second paint formulation on the right. From top to bottom, the stains are corn oil, red wine, mustard, red wine (1 hr contact time), and ink (Special Test Compound S68 available from K&N Corp.).
As can be seen from FIG. 8 , the second paint formulation, including the minerals treated with the exemplary hydrophobizing agent, exhibits markedly improved stain resistance for oil and ink stains, and appears comparable to slightly better than formulations using the untreated minerals for the wine and mustard stains.
Example 9
Paint samples were prepared using the general formulation shown in Table V, but with different pigments. A control sample was prepared using TiO 2 as the only pigment. In the test paints the TiO 2 was reduced in steps from 202 to 65 pounds per 100 gallons and replaced by volume by either a 1 micron stearate coated calcium carbonate (Camel-Cal ST, available from Imerys), a 0.7 micron stearate coated calcium carbonate (Imerseal 75, available from Imerys), and a 1 micron uncoated Calcium carbonate.
TABLE V
Standard 20% PVC Formulation
MATERIAL
LBS
WATER
111.5
COLLOIDS 226
7.4
IGEPAL CO-630
2.8
AMP-95
3.7
COLLOIDS 691
5.6
TIO2(R-706)
202.5
NATROSOL PLUS
2.8
HIGH SPEED DISPERSE
AQUAMAC 440
483.0
ETHYLENE GLYCOL
27.9
TEXANOL
36.4
WATER
111.5
ACRYSOL TT-935
1.4
AMMONIA
1.9
WEIGHT SOLIDS:
43.4%
VOLUME SOLIDS:
31.9%
The results are shown in FIG. 9 . It appears that up to about 20% of the TiO 2 content can be replaced with 1 micron stearate coated calcium carbonate while maintaining opacity comparable to that of the TiO 2 sample. Similarly, up to about 30% of the TiO 2 content can be replaced with 0.7 micron stearate coated calcium carbonate while maintaining opacity comparable to that of the TiO 2 sample. In contrast, the uncoated calcium carbonate shows a much more immediate decrease in opacity when used as a replacement for TiO 2 .
Example 10
Using the same base 20% PVC formulation as Example 9, the TiO 2 was replaced by volume with premium hydrous kaolins, a fine hydrous kaolin (ASP G90, available from BASF/Engelhard) and an ultrafine hydrous kaolin (Polygloss 90, available from Kamin). Neither hydrous kaolin was coated. FIG. 10 compares these results with those of the coated calcium carbonate samples from Example 9.
As shown in FIG. 10 , the opacity obtained by replacing TiO 2 with the 1 micron stearate coated carbonate or the 0.7 micron calcium carbonate is similar to that obtained by replacing TiO 2 with either of the premium hydrous kaolins.
As shown in FIG. 11 , the paints prepared using stearate coated calcium carbonate show less of a decrease in tint strength than those using either of the premium hydrous kaolins as a TiO 2 replacement.
Example 11
One sample of calcined Kaolin (Glomax LL, available from Imerys) was coated with Raybo 57 hydrophobizing agent and another was coated with a silane (Dynasylan OCTEO, available from Evonik Industries). Paints using these samples were made using the same 65% PVC formulation in Table VI.
TABLE VI
65% PVC formulation
MATERIAL
LBS
WATER
346.9
KTPP
1.8
TAMOL 731
8.0
IGEPAL CO-610
4.0
COLLIDS 681F
3.0
TIO2(R-706)
81.7
#10 WHITE
253.0
GLOMAX LL
199.9
NATROSOL PLUS
3.9
Grind to 4NS
902.2
UCAR 379
211.0
ETHYLENE GLYCOL
25.0
TEXANOL
10.0
WATER
46.0
Weight Solids
55.7%
Volume Solids
36.7%
White and tinted paint optical data for films prepared using these samples is shown in Table VII.
TABLE VII
FATTY ACID
SILIANE
UNCOATED
COATED
COATED
60 Degree Gloss
3.0
2.9
2.9
85 Degree Sheen
2.7
2.6
2.3
L
95.3
94.9
94.7
A
−0.6
−0.7
−0.7
B
1.9
2.3
2.1
Opacity (Y)
96.0
95.6
93.6
Whiteness
82.1
79.6
79.8
Yellowness
3.2
3.9
3.7
457 Brightness
88.7
87.4
87.2
BLUE TINT 11 Pounds blue to 100 gallons of paint
L
75.2
75.1
73.7
a
−16.1
−16.1
−16.7
b
−21.1
−20.9
−22.6
Delta L
0.0
−0.1
−1.5
Delta a
0.0
−0.1
−0.6
Delta b
0.0
0.2
−1.5
Delta E
0.0
0.2
2.2
Scrub test results for these samples is shown in FIG. 12 . Note that the scrub resistance, burnish and stain resistance of the samples using silane treated calcined kaolin are both better than either of the samples prepared using uncoated or fatty acid coated calcined kaolin.
Example 12
This example illustrates the utility of the hydrophobic treated minerals described herein to replace TiO 2 in aqueous paints.
A series of paint formulations were made as shown in Table VIII using varying amounts of TiO 2 , and replacement pigments (to constant volume) including an uncoated 1 microns calcium carbonate (Camel-Cal ST), a hydrophobic, coated calcium carbonate (Imerseal 75) or two fine hydrous kaolin controls (0.25 micron kaolin (Polygloss 90, available from Kamin) and 0.18 micron hydrous kaolin (ASP G90, available from BASF/Engelhard).
TABLE VIII
SEMI-GLOSS FORMULATION (20% PVC)
20% PVC Enamel
All TiO2 Control
MATERIAL
GALLONS
LBS
WATER
13.38
111.46
COLLOIDS 226
0.81
7.43
IGEPAL CO-630
0.32
2.79
AMP-95
0.46
3.72
COLLIDS 691
0.77
5.57
TiO 2 (R-706)
6.08 to 4.56
202 to 151
Constant volume of
CaCO 3 or Kaolin
0 to 1.52
variable
6.08 Gallons
NATROSOL PLUS
0.30
2.79
GRIND TOTALS
22.11
336.24
AQUAMAC 440
56.16
483.00
ETHYLENE
3.00
27.87
GLYCOL
TEXANOL
4.96
36.39
WATER
13.38
111.46
ACRYSOL TT-935
0.16
1.39
AMMONIA
0.22
1.86
TOTAL PAINT
100.00
998.22
Films were made using these samples, and contrast ratio (i.e., opacity) was measured for these films as previously described. The results are shown in FIGS. 13 and 14 .
As can be seen in FIGS. 13 and 14 , the replacement of a portion of the TiO 2 in an aqueous paint formulation with a hydrophobically coated mineral as described herein (in this example, a hydrophobically coated calcium carbonate) can unexpectedly provide an opacity equal to, or in some cases, even surpassing, that of an equal volume of TiO 2 . Without wishing to be bound by theory, it is hypothesized that this increase in opacity may be the result of an improvement of the spacing of the TiO 2 in the formulation.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. | A water-based paint composition may include at least one mineral treated with at least one hydrophobizing agent. The at least one mineral may include at least one of clay, kaolin, mica, titanium dioxide, talc, natural or synthetic silica or silicates, feldspars, nepheline syenite, talc, wollastonite, diatomite, barite, glass, and calcium carbonate. The at least one hydrophobizing agent may include at least one of fatty acids, fatty amines, and silanes. A method of making water-based paint may include treating at least one mineral with a hydrophobizing agent, and combining the at least one treated mineral with a binder. | 2 |
BACKGROUND OF THE INVENTION
D-amino acid oxidase ("DAO;" EC No. 1.4.3.3 ), which occurs widely in microorganisms as well as in tissues of animals, is known to be able to convert cephalosporin C ("Ceph C"), a D-α-amino acid, to α-ketoadipyl cephalosporanic acid ("α-ketoadipyl 7-ACA") , hydrogen peroxide, and ammonia. α-ketoadipyl 7-ACA, upon reaction with hydrogen peroxide, can be further transformed into glutaryl-7-aminocephalosporanic acid ("GL-7-ACA"). Since GL-7-ACA is a starting material for the production of cephem antibiotics, DAO is of great industrial interest.
SUMMARY OF THE INVENTION
An aspect of this invention relates to a method of converting Ceph C to GL-7-ACA. The method includes the steps of (i) obtaining a cell preparation, i.e., a cellfree extract or a suspension of permeated cells, from a microorganism (e.g., a fungus) which produces DAO; (ii) adding a D-α-amino acid to the cell preparation; (iii) after the adding step, heating the cell preparation at 50°-75° C. for 5-60 minutes (preferably, at 50°-65° C. for 10-40 minutes); and (iv) incubating cephalosporin C in the cell preparation. Apparently, heating of the cell preparation in the presence of D-α-amino acid has no effect on DAO activity but inactivates certain degradable enzymes (e.g., esterases), thereby increasing the conversion rate of Ceph C. After the incubating step, exogenous H 2 O 2 can be added to the cell preparation for initial conversion or more conversion to GL-7-ACA, if necessary or desirable.
A second aspect of this invention relates to another method of converting Ceph C to GL-7-ACA by first obtaining a cell preparation, a cell-free extract or a suspension of permeated cells, from a microorganism of the Rhodosporidium genus (e.g., Rhodosporidium toruloides); and then incubating Ceph C in the cell preparation, thereby producing GL-7-ACA in the absence of exogenous hydrogen peroxide. If desirable, exogenous H 2 O 2 can be added to the cell preparation for more conversion to GL-7-ACA after the incubating step.
A still further aspect of this invention relates to a method of rapidly screening for microorganism (such as a fungus, e.g., a yeast) which produce DAO. The method includes the steps of (i) growing cells of a target microorganism on the surface of a solid medium (e.g., an agar plate), the medium including a D-α-amino acid as a nitrogen source (i.e., either as the sole or as a major nitrogen source); (ii) permeating the cellular membrane of the grown cells with the vapor of an organic solvent; and (iii) immersing the permeated cells in a solution containing a peroxidase (e.g., EC No. 1.11.1.7) and a redox dye-substrate of the peroxidase (e.g., o-dianisidine, 3,3'-5,5'-tetramethyl-benzidine or 3-amino-9-ethylcarbazole), the substrate being capable of reacting with hydrogen peroxide to form a colored product in a reaction catalyzed by the peroxidase. Preferably, the solution also contains, in addition to a redox dye and a peroxidase, a D-α-amino acid which can be the same as or different from the D-α-amino acid which is used as a nitrogen source to grow the cells. The detection of the colored product, if any, indicates that DAO is present in the microorganism.
Also contemplated within the scope of this invention is a microorganism (e.g., a yeast such as Rhodosporidium toruloides or other species of the Rhodosporidium genus) which possesses a DAO activity of 0.8-4.0 IU/mg (e.g., 0.8-1.6, 1.6-2.4, 2.4-3.2, or 3.2-4.0 IU/mg) total cellular protein when grown at 30° C. in a fully aerated medium until the OD 660 nm nm reading of the medium reaches 7-10 (i.e., the stationary phase), the medium containing a yeast carbon base and 30 mM D-α-Ala as the sole nitrogen source and having a pH of 5.6. Preferably, a cell-free extract or a suspension of permeated cells prepared from the microorganism is capable of converting Ceph C to GL-7-ACA in the absence of exogenous hydrogen peroxide, i.e., the GL-7-ACA/α-ketoadipyl 7-ACA ratio being 0.5 or greater (preferably, 0.7 or greater) in an assay identical to or equivalent to that described in Example 2 or 3 below. Such a microorganism can be identified by the screening method described in the preceding paragraph.
Other features or advantages of the present invention will be apparent from the following drawings and detailed description of several embodiments, and also from the appending claims.
BRIEF DESCRIPTION OF THE DRAWING
The drawings are first described:
FIG. 1A is an HPLC chromatogram of conversion products of Ceph C by the permeated cells of a Rhodosporidium toruloides strain (ATCC 10788) in the absence of exogenous H 2 O 2 .
FIG. 1B is an HPLC chromatogram of conversion products of Ceph C by the permeated cells of ATCC 10788 in the presence of exogenous H 2 O 2 .
FIG. 2A is an HPLC chromatogram of conversion products of Ceph C by the cell-free extract of ATCC 10788 in the presence of exogenous H 2 O 2 without heat treatment.
FIG. 2B is an HPLC chromatogram of conversion products of Ceph C by the cell-free extract of ATCC 10788 in the presence of exogenous H 2 O 2 with heat treatment.
DETAILED DESCRIPTION OF THE INVENTION
Cell-free extract or a suspension of permeated cells which is used to convert Ceph C can be prepared from microorganism cells by methods within the scope of a person of ordinary skill in the art. By "permeated cells" is meant cells the membranes of which have been permeated so that Ceph C can enter into the cells to be converted by DAO therein. For an example of how to permeate cells, see Pardee, et al., J. Mol. Biol. 1:165 (1959).
The D-α-amino acid used to practice this invention (either as a nitrogen source to induce the synthesis of DAO, as a stabilizer of DAO in heating treatment, or as a reagent in detecting DAO activity) may contain 3-20 carbons, and preferably, 3-12 carbons (e.g., D-α-Ala, D-α-Met, and D-α-Phe).
The microorganism which can be used to practice this invention or the microorganism of this invention may be a fungus, such as a yeast which belongs to the ascomycete class of fungi. Examples of such a yeast include, but are not limited to, a species of the Saccharomyces genus (e.g., S. pasteurianus), the Rhodosporidium genus (e.g., R. toruloides), the Rhodotorula genus (e.g., R. gracilis), and the Trigonopsis genus (e.g., T. variabilis).
Without further elaboration, it is believed that one skilled in the art can, based on the description herein, utilize the present invention to its fullest extent. The following specific examples are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever. Any publications cited in this disclosure are hereby incorporated by reference.
EXAMPLE 1
Screening for a microorganism which produces DAO
About 3,000 strains from culture collections and local isolates were screened. Cells from each strain were grown on the YMA medium containing 0.3% yeast extract, 0.3% malt extract, 0.5% peptone, and 2% agar were transferred to a screening medium consisting of 1.17% yeast carbon base (Difco), 0.1% D-α-Ala, and 2% agar.
To further confirm their DAO activity, strains grown on the screening medium at 30° C. for 48 hr and treated with organic solvent vapor such as chloroform for 30-45 min to permeate the cells. A 10 ml solution containing 100 mM D-α-Ala, 0.025% o-dianizidine, and 25 IU peroxidase (EC No. 1.11.1.7) in 100 mM potassium phosphate buffer (pH 8.0) was poured into the plate and incubated at room temperature for 30 min. Cells with DAO activity produced a brownish red zone. Several strains with DAO activity were isolated. R. toruloides (ATCC 10788) showed the highest activity among the isolates.
A single colony of ATCC 10788 grown on the YMA medium was inoculated into 10 ml of medium A consisting of yeast carbon base and 30 mm D-α-Ala at pH 5.6) and incubated at 30° C. and 150 rpm overnight. A 5-ml aliquot of the culture was transferred into 100 ml of medium A and shaken at 150 rpm and 30° C. for 48 hr. When the OD 660 nm of the cells reached 8.0 (i.e., stationary phase), DAO activities ranging from 0.56 to 0.62 IU/mg total cellular protein were observed. The harvested cells were broken with glass beads and the enzyme activity was measured by the Friedmann method (see Examples 3 and 4 below).
EXAMPLE 2
Conversion of Ceph C in a suspension of permeated cells without preheating treatment
ATCC 10788 was grown in a 500 ml Hinton flask containing 50 ml of YMA medium with the following composition: 1% yeast extract, 1.5% malt extract, 0.2% D,L-α-Ala (pH 6.5). The flask was incubated at 30° C. and 150 rpm on a rotary shaker for 48 h when the cells reached the stationary phase. The cells were harvested by centrifugation at 4° C. and 10,000×g for 20 min and used immediately for the preparation of the cell-free extract or permeated cells.
Cells were then suspended in chilled 100 mM potassium phosphate buffer (pH 8.0) containing 2.5% (v/v) toluene in ethanol at 0° C. for 30 min. The permeated cells were washed twice with chilled 100 mM phosphate buffer and then used for the conversion of Ceph C.
The DAO activity toward Ceph C was monitored by HPLC. The reaction mixture contained 30 μl of Ceph C (250 mM), 770 μl of potassium phosphate buffer (100 mM at pH 8.0), and 1.2 ml of permeated cells in a final volume of 2 ml. After incubation at 25° C. for 2 h, 20 μl of H 2 O 2 (3.5%) was added to the solution and the reaction proceeded for another 10 min at 25° C. The products of conversion in the supernatant were then analyzed by HPLC. The mobile phase was 10% methanol in 20 mM ammonium acetate buffer (pH 4.8). A Nova-Pack C-18 column (Waters Material Synthesis Facility, Taunton), 3.9×150 mm, was used and the UV detector was set at 260 nm. The retention times for Ceph C and GL-7-ACA at a flow rate of 1 ml/min were 2.4 min and 9.5 min, respectively.
As shown in FIGS. 1A and 1B, the permeated cells of ATCC 10788 could directly convert a part of Ceph C into GL-7-ACA without the addition of H 2 O 2 (FIG. 1A). ATCC 10788 was found to contain relatively low catalase activity as compared to that of T. variabilis (data not shown). However, the addition of H 2 O 2 further transformed the remaining a-ketoadipyl 7-ACA into GL-7-ACA (FIG. 1B). In both FIGS. 1A and 1B, peak 1 stands for Ceph C; peak 2 for a-ketoadipyl 7-ACA; and peak 3 for GL-7-ACA.
EXAMPLE 3
Conversion of Ceph C in a cell-free extract without preheating treatment
Results similar to those shown in FIGS. 1A and 1B were obtained in another experiment, which indicates that a cell-free extract prepared from a ATCC 10788 culture could also convert Ceph C into both α-ketoadipyl 7-ACA and GL-7-ACA in the absence of exogenous H 2 O 2 .
ATCC 10788 was grown in the same manner described in Example 2 above. The cell-free extract was prepared as follows: Cell paste of the ATCC 10788 culture was suspended in 100 mM potassium phosphate buffer (pH 8.0) containing 2 mM EDTA, 5 mM 2-mercaptoethanol and 0.1% (v/v) Triton X-100 and shaken vigorously with glass beads of 0.45-0.55 mm diameter for five periods of 1 min with 1 min interval at 4° C. The tubes were placed on ice during these idle intervals. The homogenate was centrifuged at 21,000×g for 30 min and the supernatant was collected for Ceph C conversion or enzyme assay.
The reaction mixture contained 2 ml of Ceph C (250 mM), 7 ml of potassium phosphate buffer (100 mM at pH 8.0), and 1.0 ml of cell-free extract in a final volume of 10 ml. After incubation at 37° C. for 1 h, 105 μmoles of α-ketoadipyl 7-ACA and 75 μmoles of GL-7-ACA were obtained. Upon addition of 150 μl of H 2 O 2 (3.5%), all of the α-ketoadipyl 7-ACA was converted to GL-7-ACA. The quantitative data were obtained by HPLC in a manner analogous to that described in Example 2 above. More specifically, the mobile phase was 10% methanol in 20 mM ammonium acetate buffer (pH4.8). A Nova-Pack C-18 column (Waters Material Synthesis Facility, Taunton), 15×0.46 cm, was used and the UV detector was set at 260 nm. The flow rate was 1 ml/min.
EXAMPLE 4
Conversion of Ceph C in a suspension of cell-free extract with preheating treatment
The cell-free extract from ATCC 10788 was prepared in the same manner described in Example 3 above.
DAO activity was assayed by measuring the productivity of keto acid according to the method of Freidemann, Methods Enzymol. 3:414 (1957). The reaction mixture contained 100 mM D-α-Ala, 100 mM potassium phosphate buffer (pH 8.0), 400 IU of bovine liver catalase, and an appropriate amount of enzyme in a final volume of 1 ml. After incubation at 37° C. for 15 min, the keto acid produced was determined by a colorimetric assay using 2,4-dinitrophenylhydrazine and compared against the standard curve for pyruvic acid. One unit (IU) of DAO activity corresponds to the formation of 1 μmole of keto acid per min at 37° C.
ATCC 10788 was shown to possess high esterase activity (data not shown) which might give rise to unknown side products appeared before peak 1 in Ceph C conversion (FIGS. 1A and 1B). Ceph C or D-α-Ala was used to raise the thermal tolerance of DAO in a heating treatment of the cellfree extract aimed at inactivating undesirable degradative enzymes such as esterases. Less than half of the DAO activity in the cell extract containing Ceph C was lost after heating at 55° C. for 5 min. No activity could be detected after repeating the same treatment for five times. On the other hand, no loss of DAO activity was observed after heat treatment in the presence of 100 mM D-α-Ala. The results were summarized in Table 1 below:
TABLE 1______________________________________Thermostability of DAO in thepresence of a substrate Relative activity(%).sup.aCell extract in Treatment 1.sup.b Treatment 2.sup.c______________________________________Phosphate buffer (pH 8.0) 4 3Phosphate buffer (pH 8.0)+100 mM Ceph C 56 0+100 mM D-α-Ala 100 100______________________________________ .sup.a Enzyme activity before treatment was 100%. .sup.b Heated at 55° C. for 5 min. .sup.c Heated repeatedly at 55° C. for 5 min for five cycles, each with 1min interval on ice.
The results indicated that the thermal tolerance of DAO could be greatly enhanced by the presence of Ceph C or D-α-Ala. D-α-Ala was particularly effective in protecting DAO during heat treatment. The lesser effect of Ceph C is believed to be due to thermal lability of that compound.
It was further observed that the side products formed during Ceph C conversion with the D-α-Ala/preheated cell extract were substantially decreased and the yield of GL-7-ACA was higher than that of untreated cell extract (compare FIG. 2A with FIG. 2B). More specifically, shown in FIGS. 2A and 2B are HPLC chromatograms of the products of Ceph C conversion by untreated cell extract (FIG. 2A), and by the cell extract repeatedly heated at 55° C. for 5 min for five cycles, each with 1-min interval on ice (FIG. 2B); exogenous H 2 O 2 was added after the conversion of Ceph C in both experiments. In each of FIGS. 2A and 2B, peaks 1 stand for unknown side products, peak 2 stands for Ceph C, and peak 3 stands for GL-7-ACA. The HPLC assay was performed in a manner identical to that described in Example 2 above.
Other Embodiments
From the above description, one skilled in the art can easily ascertain the essential characteristics of the present invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. Thus, other embodiments are also within the claims. For example, conversion of a D-α-amino acid analogue of Ceph C in manners similar or identical to those described in Examples 2-4 is also within the scope of this invention under the doctrine of equivalents. | A method of converting cephalosporin C to glutaryl-7-aminocephalosporanic acid. The method including obtaining a cell preparation from a microorganism which produces D-amino acid oxidase, the preparation being a cell-free extract or a suspension of permeated cells; adding a D-α-amino acid to the preparation; after the adding step, heating the preparation at 50°-75° C. for 5-60 minutes; and incubating cephalosporin C in the preparation. Also disclosed are a method of converting cephalosporin C to glutaryl-7-aminocephalosporanic acid in the absence of exogenous H 2 O 2 , and a method of screening for a D-amino acid oxidase-producing microorganism. | 2 |
BACKGROUND OF THE PRIOR ART
This invention relates generally to chairs and in particular to chairs that convert from a chair comprising a seat and back rest to a chair comprising a seat and knee rest and back again.
Conventional chairs utilizing a seat and back rest are well known as are conventional chairs in which the tilt of the seat and the tilt of the back rest can be adjusted by various means and mechanisms.
In these chairs, the adjustments are primarily for the purpose of increasing the comfort of the person sitting in the chair or adjusting the tilt of the seat and back rest to accommodate persons of different sizes.
Similarly, backless chairs utilizing a forward tilted seat and a knee rest are also well known.
However, chairs that convert from the conventional form of a seat, in which the back rest is located above the level of the seat, into a backless chair utilizing a tilted forward seat and knee rest located below the level of the seat are not well known and represents an improvement over both types of chair.
SUMMARY OF THE INVENTION
Applicant's improvement is a convertible chair comprising a base support in which the seat is pivotally connected to the base support and a back-knee rest that is also pivotally connected to the base support.
In the first position, the seat is positioned in a generally horizontal plane to support the thighs and buttocks of a user of the chair and the back-knee rest is positioned above the level of the seat to support the back of the user of the chair.
By rotating or pivoting the seat about its pivot point either along a vertical plane or along a tilted plane, the seat is caused to tilt from a first position as a conventional chair in which the seat is adapted to support the buttocks and thighs of a user of the chair and the back-knee rest is adapted to support the back of a user of the chair, to a backless chair with the seat tilted at a predetermine angle.
By rotating or pivoting the back-knee rest about its pivot point either along a vertical plane or along a tilted plane, the back-knee rest is caused to move from a first position located above the level of the seat to a second position below the level of the seat and at a predetermine angle of tilt, at which position the seat is adapted to support the thighs and buttocks of the user of the chair and the back-knee rest is adapted to support the knees of the user of the chair.
It is, therefore, an object of the present invention to provide a chair that is convertible from a conventional chair to a backless knee rest chair or from a backless knee rest chair to a conventional chair.
It is a further object of the present invention to provide a chair in which the seat and back-knee rest are pivotally connected to the common base support and, when pivoted about their respective pivot points, convert the chair from a conventional chair to a backless knee rest type chair or from a backless knee rest chair to a conventional chair.
It is yet another object of the present invention to provide a chair in which the seat and back-knee rest are convertible from a conventional chair to a back-knee rest chair in which the back-knee rest is adjustable relative to the seat.
It is a further object of the present invention to provide a chair that can be converted from a conventional chair to a backless knee rest chair or a backless knee rest chair to a conventional chair with the simultaneous pivoting of the seat and back-knee rest about their respective pivot points through the pivoting of the back-knee rest about its pivot point.
These and other objects of the present invention will become manifest upon study of the following description when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of the convertible chair of the present invention showing the chair with the seat and back-knee rest in their conventional relationship.
FIG. 2 a back elevational view of the chair of FIG. 1 taken at line 2--2.
FIG. 3 is a side elevational view of the chair of FIG. 1 in its converted configuration with the seat tilted at an angle and the back-knee rest disposed below the level of the seat at a predetermined angle to the horizontal.
FIG. 4 is a back elevational view of the converted chair of FIG. 3 taken at line 4--4.
FIG. 5 is a side elevational view of a second embodiment of the convertible chair of the present invention showing the chair with the seat and back-knee rest in their conventional relationship.
FIG. 6 is a back elevational view of the chair of FIG. 1 taken at line 6--6.
FIG. 7 is a side elevational view of the chair of FIG. 5 in its converted configuration with the seat tilted at an angle and the back-knee rest disposed below the level of the seat at a predetermined angle to the horizontal.
FIG. 8 is a back elevational view of the converted chair of FIG. 7 taken at line 8--8.
FIG. 9 is a side elevational view of a third embodiment of the convertible chair of the present invention showing the chair with the seat and back-knee rest in their conventional relationship.
FIG. 10 is a back elevational view of the chair of FIG. 9 taken at line 10--10.
FIG. 11 is a side elevational view of the chair of FIG. 9 in its converted configuration with the seat tilted at an angle and the back-knee rest disposed below the level of the seat at a predetermined angle to the horizontal.
FIG. 12 is a back elevational view of the converted chair of FIG. 11 taken at line 12--12.
FIG. 13 is a bottom view of the underside of the seat of FIG. 11 taken at lines 13--13 showing the method of holding tilt of the seat in position.
FIG. 14 is a side elevational view of a fourth embodiment of the convertible chair of the present invention showing the chair with the seat and back-knee rest in their conventional relationship.
FIG. 15 is a back elevational view of the chair of FIG. 14 taken at line 15--15.
FIG. 16 is a side elevational view of the chair of FIG. 14 in its converted configuration with the seat tilted at an angle and the back-knee rest disposed below the level of the seat at a predetermined angle to the horizontal.
FIG. 17 is a back elevational view of the converted chair of FIG. 11 taken at line 17--17.
FIG. 18 is an isometric view of the method of connecting the back-knee rest to its support leg.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIGS. 1 through 4, there is illustrated a first embodiment of the convertible chair 10 of the present invention showing it configured as a conventional chair in FIGS. 1 and 2 and configured as a backless knee rest chair in FIGS. 3 and 4.
FIG. 1 is a side elevational view of the convertible chair 10 of the present invention in which seat 12 is disposed in a generally horizontal position with back-knee rest 14 disposed in a generally vertical position and located above the level of seat 12.
In this position seat 12 is adapted to support the buttocks and thighs of the user while back-knee rest 14 is adapted to support the back of the user.
FIG. 2 is a back elevational view of convertible chair 10 illustrated in FIG. 1 taken at line 2--2.
FIG. 3 is a side elevational view of convertible chair 10 in its converted position in which, what was the front of horizontally disposed seat 12 has been rotated and is now tilted upwardly from the horizontal while back-knee rest 14 has been rotated downwardly such that the top of vertically disposed back-knee rest 14 in FIG. 1, is now tilted from the vertical and back-knee rest 14 is positioned below the level of seat 12.
In this position seat 12 is adapted to support the buttocks and thighs of the user while back-knee rest 14 is adapted to support the knees of the user of the chair.
FIG. 4 is a back elevational view of convertible chair 10 shown in FIG. 3 taken at line 4--4.
Convertible chair 10 comprises, basically, a base support 18, mounted on a set of casters or wheel members 20.
Attached to base support 20 and projecting upwardly therefrom is support pedestal 22 comprising a pair of parallel disposed support legs 23 shown in FIGS. 2 and 4.
Pivotally mounted proximate the top of pedestal 22, using hinge or pivot pin 24, is seat 12.
Back-knee rest arcuate bracket arm 26 is used to connect back-knee rest 14 to base support pedestal 22 and seat 12.
In particular, the lower end of back-knee rest bracket arm 26 is pivotally connected to the underside of seat 12 using pivot pin 30. Back-knee rest arcuate bracket arm 26 is also provided with a plurality of spaced apart holes 32 along the arcuate portion of its length which are coordinated with spaced apart holes 34 in pedestal 22 to receive locking pin 36. Locking pin 36 is adapted to simultaneously engage a hole 32 in back-knee rest bracket arm 26 and a hole 34 in support pedestal 22 to rigidly connect back-knee rest arcuate bracket arm 26 to pedestal 22.
Back-knee rest 14 is also pivotally connected, using pivot pin 38, to the end of back-knee rest bracket arm 26 distal seat 12.
In FIG. 1, it can be seen that the fixed position of seat 12 relative to back-knee rest 14 is maintained by the use of pins 24, 30 and 36 which define the points of a structural triangle.
To convert chair 10 from a conventional chair, as illustrated in FIGS. 1 and 2, to a knee rest chair, illustrated in FIGS. 3 and 4, pin 36 is removed from holes 32 and 34 thus leaving back-knee rest arcuate bracket arm 26 free to rotate about pivot pin 30. Concurrently, seat 12 is now allowed to rotate freely about pivot pin 24.
Back-knee rest bracket arm 26 is then rotated downwardly to the position shown in FIG. 3 in which back-knee rest 14 is positioned below the level of seat 12.
After the tilt of seat 12 and the location of back-knee rest 14 have been adjusted for maximum comfort, pin 36 is then inserted through the hole 32 in back-knee rest bracket arm 26 and the hole 34 in pedestal 22 nearest each other as shown in FIG. 3. Here again, pins 24, 30 and 36 define points of a structural triangle whereby the seat and back-knee rest combination are made into a rigid structure.
The user of the chair in FIGS. 3 and 4 can now use seat 12 as a support for the buttocks and thighs will using back-knee rest 14 as a support for the knees.
The distance between seat 12 pivot pin 24 and back-knee rest bracket arm 26 pivot pin 30 is determined by the amount of tilt or angle that seat 12 makes with the horizontal and the distance back-knee rest 14 is located away from seat 12 when back-knee rest 14 is positioned below the level of seat 12 and the distance it is located away from seat 12 when positioned above the level of seat 12.
With reference to FIGS. 5 through 8, there is illustrated a second embodiment of the convertible chair 110 of the present invention showing it configured as a conventional chair (FIGS. 5 and 6) and as a knee rest chair (FIGS. 7 and 8).
FIG. 5 is a side elevational view of the convertible chair 110 of the present invention in which seat 112 is disposed in a generally horizontal position with back-knee rest 114 disposed in a generally vertical position and located above the level of seat 112. In this position seat 112 is adapted to support the buttocks and thighs of the user while back-knee rest 114 is adapted to support the back of the user.
FIG. 6 is a back elevational view of convertible chair 110 illustrated in FIG. 5 taken at line 6--6.
FIG. 7 is a side elevational view of convertible chair 110 in its converted position in which, what was the front of horizontally disposed seat 112, is now rotated upwardly from the horizontal while back-knee rest 114 is rotated downwardly such that vertically disposed back-knee rest 114, in FIG. 5, is now tilted from the vertical and back-knee rest 114 is located below the level of seat 112. In this position seat 112 is adapted to support the buttocks and thighs of the user while back-knee rest 114 is adapted to support the knees of the user of the chair.
FIG. 8 is a back elevational view of convertible chair 110 shown in FIG. 7 taken at line 8--8.
Convertible chair 110 comprises, basically, a base support 118, mounted on casters or wheel members 120. Attached to base support 120 and projecting upwardly therefrom is support pedestal 122.
Support pedestal 122 comprises a base pedestal 124 attached to base support 118. Proximate the top of support pedestal 124 is back-knee rest bracket arm support plate 126 tilted upwardly at an angle. Attached to back-knee rest bracket arm support plate 126, as by welding or the like, is back-knee rest bracket arm shaft 128 having a longitudinal axis of rotation 130 disposed at right angles to the plane of back-knee rest bracket arm support plate 126.
Back-knee rest bracket arm 132 is journaled to shaft 128 and allowed to rotate about shaft 128 while the other end of back-knee rest bracket arm 132 is pivotally connected to back-knee rest 114 using pivot pin 134. Back-knee rest bracket arm 132 comprises a back-knee rest support end 133 extending from shaft 128 to back-knee rest pivot pin 134, and a seat support end 135 extending from shaft 128 to seat support pin 137.
Bearing block 140 attached to shaft 128, as by set screws or the like, on the side of back-knee rest bracket arm 132 distal back-knee rest bracket arm support plate 126 is used to cause back-knee rest bracket arm 132 to bear against support plate 126 and reduce any bending moment on shaft 128.
Back-knee rest shaft 128 is attached at its top end, as by welding or the like, to the bottom end of seat pivot pin or shaft 136 to become a rigid unit.
The longitudinal axis of rotation 138 of pivot pin or shaft 136 also projects upwardly at an angle which is not necessarily the same angle as the longitudinal axis of rotation 130 of back-knee rest shaft 128.
Hub 139 attached to the underside of seat 112 is journaled to pivot pin or shaft 136 whereby axis of rotation 138 makes and angle "A" with the horizontal plane of seat 112 or the plane of the bottom or top surface of seat 112.
To convert chair 110 from a conventional chair in FIGS. 5 and 6 to a knee rest chair in FIGS. 7 and 8, seat 112 is rotated 180 degrees about shaft 136 so that seat front 142 (in FIG. 5) is positioned to the back (in FIG. 7) and, by virtue of the angle of shaft 136 to the plane of seat 112, seat 112 is tilted upwardly as shown in FIG. 7.
Back-knee rest bracket arm 132 is also rotated 180 degrees from its position in FIG. 5, where back-knee rest is disposed in a vertical plane above the level of seat 112, to the position shown in FIG. 7, where back-knee rest 14 is tilted at an angle to the vertical and is located below the level of seat 112.
Seat support pin 137 is now in a position to engage seat support bracket member 141 attached to the underside of seat 112 in order to provide a rigid position for seat 112.
It can be seen that the angle of tilt of seat 112 is determined by the angle of tilt of longitudinal axis of rotation 138 of shaft 136.
The angle of tilt that seat 112 makes with the horizontal will be double the angle of tilt that longitudinal axis of rotation 138 makes with the vertical.
In a like manner, the angle that back-knee rest 114 makes with the horizontal and its position relative to seat 112 will be determined by the angle that longitudinal axis of rotation 130 makes with the vertical and the position where back-knee rest bracket arm 232 is journaled to shaft 128 relative to seat 112.
By pivoting back-knee rest 114 about pivot pin 134, the tilt of back-knee rest 114 for maximum knee comfort can be adjusted as desired.
With reference to FIGS. 9 through 13, there is illustrated a third embodiment of the convertible chair 210 of the present invention showing it configured as a conventional chair and as a knee rest chair.
FIG. 9 is a side elevational view of the convertible chair 210 of the present invention in which seat 212 is disposed in a generally horizontal position with back-knee rest 214 disposed in a generally vertical position and located above the level of seat 212. In this position seat 212 is adapted to support the buttocks and thighs of the user while back-knee rest 214 is adapted to support the back of the user.
FIG. 10 is a back elevational view of convertible chair 210 illustrated in FIG. 9.
FIG. 11 is a side elevational view of convertible chair 210 in its converted position in which, what was the front of horizontally disposed seat 212, is now rotated upwardly from the horizontal while back-knee rest 214 is rotated downwardly such that vertically disposed back-knee rest 214, in FIG. 9, is now tilted at an angle to the vertical and back-knee rest 214 is located below the level of seat 212. In this position seat 212 is adapted to support the buttocks and thighs of the user while back-knee rest 214 is adapted to support the knees of the user of the chair.
FIG. 12 is a back elevational view of convertible chair 10 shown in FIG. 11 taken at line 12--12.
FIG. 13 is a plan view of the underside of seat 212 showing the structure of the apparatus for maintaining seat 212 in a horizontal or tilted position.
Convertible chair 210 comprises, basically, a base support 218, mounted on casters or wheel members 220. Attached to base support 218 and projecting upwardly therefrom is support pedestal 222.
Pivotally connected proximate the top of pedestal 222 is pivot joint 224 to which seat 212 and seat support 228 are pivotally connected using pivot pin 226.
Also attached proximate the top of pedestal 222 is back-knee rest bracket arm support 230.
A back-knee rest bracket arm 132 is pivotally connected to bracket arm support 230 using pivot pin 234.
Back-knee rest bracket arm 232 comprises a pair of parallel disposed bracket arm legs 236 and 238 as shown in FIGS. 10, 12 and 13. Bracket arm legs 236 and 238 are adapted to straddle pedestal 222 which acts as a guide and support to prevent lateral or sideways movement of back-knee rest bracket arm 232 as it rotates about pivot pin 234.
One end of back-knee rest bracket arm 232 is pivotally connected to back-knee rest 214 using pivot pin 242.
The other end of back-knee rest bracket arm 232 is provided with a bar or rod 244 attached perpendicular to back-knee rest bracket arm 232 and bracket arm legs 236 and 238 (FIG. 13) and cantilevering outwardly therefrom.
Bar or rod 244 is adapted to engage grooves 246 in grooved support blocks 248 and 250 attached to the underside of seat 212 on each side of back-knee rest bracket arm 232.
To convert chair 210 from a conventional chair in FIGS. 9 and 10 to a knee rest chair in FIGS. 11 and 12, seat 212 is rotated about pivot pin 226 to disengage bar or rod 244 from a groove 246 in grooved support blocks 248 and 250.
Back-knee rest bracket arm 232 is then rotated about pivot pin 234 from its position in FIG. 9 where back-knee rest 214 is disposed in a vertical plane above the level of seat 212 to the position shown in FIG. 12 in which back-knee rest 214 is position below the level of seat 212 and tilted at an angle to the vertical.
Seat 212 is then allowed to rotate back so that bar or rod 244 engages another groove 246 in grooved support blocks 248 and 250.
It can be seen that the rigidity of the chair structure is maintained by the fixed positions of pivot pins 234 and 226 and the point of engagement of bar or rod 244 with any one of grooves 246.
The rigidity is further insured by the pressure applied to the seat by the buttocks and thighs of a user of chair 212 as well as the upward pressure of bar of rod 244 against groove 246 resulting from the downward pressure of the knees of the user on back-knee rest 214 acting through pivot pin 234.
With reference to FIGS. 14 through 18, there is illustrated a fourth embodiment of the convertible chair 310 of the present invention showing it configured as a conventional chair and as a knee rest chair.
FIG. 14 is a side elevational view of the convertible chair 310 of the present invention in which seat 312 is disposed in a generally horizontal position with back-knee rest 314 disposed in a generally vertical position and located above the level of seat 312. In this position seat 312 is adapted to support the buttocks and thighs of the user while back-knee rest 314 is adapted to support the back of the user.
FIG. 15 is a back elevational view of convertible chair 310 illustrated in FIG. 14 taken at line 15--15.
FIG. 16 is a side elevational view of convertible chair 310 in its converted position in which, what was the front of horizontally disposed seat 312, is now rotated upwardly from the horizontal while back-knee rest 314 is rotated downwardly such that vertically disposed back-knee rest 314 (in FIG. 14), is now tilted at an angle to the vertical and back-knee rest 314 is located below the level of seat 312. In this position seat 312 is adapted to support the buttocks and thighs of the user while back-knee rest 314 is adapted to support the knees of the user of the chair.
FIG. 17 is a back elevational view of convertible chair 310 shown in FIG. 16 taken at line 17--17.
FIG. 18 is an isometric view of the method of connecting back-knee rest 314 to back-knee rest bracket arm 326 and adjusting it as a backrest and as a knee rest.
Convertible chair 310 comprises, basically, a base support leg 318, mounted on lateral support members 320. Pivotally connected to base support leg 318 by hinge or pivot pin 328 and projecting upwardly therefrom is support pedestal 322.
Journalled to support pedestal 322 is pivot shaft 324 attached to the underside of seat 312 and pivotally connecting seat 312 to base support leg 318. An adjustment handle 330 (FIGS. 16 and 17) in cooperation with a threaded section 332 (FIG. 14) and nut member 333 (FIG. 17), is adapted to frictionally engage base support leg member 318 so that the tilt of seat 312 can be adjusted relative to base support member 318.
A spreader support member 334 is pivotally connected, at one end, using pivot pin 336, to base support leg 318 and at it other end is adapted to engage one of several grooves 338.
Attached to back-knee rest 314 is back-knee rest support bracket 342.
With reference to FIG. 18, the inside portion of back-knee rest bracket arm 326 proximate back-knee rest 314 is provided with a first groove 350 running parallel to the longitudinal axis of back-knee rest bracket arm 326.
A second groove 352 intersecting first groove 350 at junction 354 is provided proximate the upper or top end of back-knee rest bracket arm 326 and with the longitudinal axis of groove 352 running at an angle to the longitudinal axis of back-knee rest bracket arm 326 such that the longitudinal axis of groove 352 will be disposed vertically when chair 310 is in its conventional configuration shown in FIGS. 14 and 15.
Grooves 350 and 352 are adapted to receive pin or guide members 356 and 358 attached to back-knee rest suppport bracket 342.
A back-knee rest bracket arm support bar connector member 360 connects the two back-knee rest support legs 326 together. Back-knee rest bracket arm support bar connector member 360 also acts as a further support for back-knee rest support bracket 342 proximate its lower end when chair 310 is in the conventional position shown in FIG. 14, and as a support proximate the top end of back-knee rest support bracket 342 when the chair is converted to a knee rest chair as shown in FIG. 16.
As can be seen in FIG. 16, a first hole 362 is provided in base support 318 while a second hole 364 is provided in Back-knee rest bracket arm 326.
When first hole 362 in base support leg 318 is aligned with second hole 364 in back-knee rest bracket arm 326, a pin 366 (as shown in FIG. 14) can be inserted into both holes so that base support 318 is fixedly connected to back-knee rest bracket arm 326 when chair 310 is converted to a conventional chair.
As can be seen in FIG. 14, a third hole 372 is provided in base support leg 318 and a fourth hole 374 is provided in back-knee rest bracket arm 326.
When third hole 372 is aligned with fourth hole 374, pin 366 (as shown in FIG. 16) can be now inserted into both holes so that base support 318 is fixedly connected to back-knee rest bracket arm 326 when chair 310 is converted to a knee rest chair.
A further support arm 382 can be provided to furnish additional rigidity to chair 310.
Support arm 382 is pivotally connected to back-knee rest support arm 326 using pivot pin 384. Support pin 386 is attached the other end of support arm 382 and is adapted to engage one of several grooves 386 (FIG. 16) when chair 310 is in the conventional position (FIG. 14).
When converted to a knee rest chair, support pin 386 attached to support arm 382 is adapted to engage one of several grooves 388 in base support leg 318.
To convert chair 310 from a conventional chair, as shown in FIG. 14, to a knee rest chair, as shown in FIG. 16, back-knee rest 314 is moved vertically upward allowing pins or guides 354 and 356 (FIG. 18) to slide upwardly guided by second groove 352 until pins 354 and 356 reach the intersection 354 of first groove 350 with second groove 352.
When pin or guide 356 is in a position to engage first groove 350, back-knee rest 314 is rotated to align pins or guides 354 and 356 with first groove 350 to allow back-knee rest 314 to now assume a position parallel to back-knee rest bracket arm 326 and slide down into the knee rest position shown in FIG. 16.
Pin 366 is removed from first and second holes 362 and 364, respectively, and back-knee rest bracket arm 326 is rotated downwardly until third and fourth holes 374 and 376 are aligned. In this position, pin 366 is inserted to engage both third and fourth holes 374 and 376, respectively.
When an appropriate height of seat 312 is established, pin 337 of spreader support member 334 is then placed in the nearest groove 338 so that a three point support is provided defined by pivot pin 336, pin 366 and a groove 338.
When the appropriate height of back-knee rest 314 is established, pin 386 of support arm 382 placed in one or several grooves 388.
Adjustment handle 330 is then operated to adjust the angle of seat 312 for maximum comfort.
To convert chair 310 back into the conventional chair of FIG. 14, the process is reversed whereby back-knee rest bracket arm 326 is rotated upwardly raising back-knee rest 314 from a position below the level of seat 312 to a position above the level of seat 312.
Back-knee rest 14 is also rotated from a position parallel to back-knee rest bracket arm 326 to a vertical position at an angle to back-knee rest bracket arm 326.
Thus is disclosed a chair that will convert from a conventional chair to a knee rest chair. | A chair that converts from a conventional seat and back rest type of chair to a seat and knee rest type of chair utilizes a seat that is pivotally connected to a base support that, when pivoted, is rotated from a generally horizontal plane when used as a conventional chair, to a predetermined angle of tilt. The back rest is also pivotally connected to the base support by a bracket arm that permits the back-knee rest to be moved from a position above the plane of the seat, to support the back of a person sitting on the horizontally positioned seat, to a position below the plane of the seat and at a predetermined angle of tilt to support the knees of a person sitting on the tilted seat. | 0 |
FIELD OF THE INVENTION
This invention relates to new oxadiazolyl-alkyl-purine derivatives and pharmaceutically acceptable salts thereof, a process for the preparation thereof and pharmaceutical compositions comprising the same.
SUMMARY OF THE INVENTION
The new compounds of the present invention are particularly useful antitussive agents in the treatment of the diseases of the respiratory organs.
The compounds of the present invention are oxadiazolyl-alkyl-derivatives of the Formula I and pharmaceutically acceptable salts thereof ##STR2## wherein A stands for C 1-4 alkylene and
R 1 represents C 1-6 alkyl, hydroxyalkyl, halogenoalkyl, carboxyalkyl, C 5-6 cycloalkyl or aminoalkyl of the Formula --(CH 2 ) n --NR 2 R 3 in which group n is an integer from 1 to 3; R 2 and R 3 each stand for hydrogen or C 1-4 alkyl or together with the adjacent nitrogen atom they are attached to form a 5- or 6-membered nitrogen-containing heterocyclic ring which may optionally comprise a further nitrogen atom or an oxygen atom as heteroatom; or
R 1 stands for phenyl, hydroxyphenyl, carboxyphenyl, benzyl or dimethoxybenzyl).
The term "alkyl" encompasses both straight and branched chain groups. The benzyl group is preferably 3,4-dimethoxybenzyl.
The salts of the compounds of the Formula I can be salts formed with inorganic acids (e.g. hydrochloric acid, sulfuric acid, phosphoric acid) or organic acids, e.g. carboxylic or sulfonic acids (e.g. acetic acid, tartaric acid, maleic acid, lactic acid, citric acid, ascorbic acid, benzoic acid, hydroxy benzoyl benzoic acid, nicotinic acid, methanesulfonic acid or toluene sulfonic acid). The said salts are acid addition salts. The compounds of the Formula I also form salts with bases (e.g. alkaline and alkaline earth metals, such as sodium, potassium, calcium, magnesium). The salts may also be complex salts (e.g. salts formed with ethylene diamine).
Organic substances occuring in nature and derivatives thereof have long been used in the treatment of diseases of the organs of respiration as antitussive agents. For this purpose particularly morphine type compounds are used, the most well-known antitussive reresentative thereof being codeine. The said compounds act on the central nervous system in a non-specific manner and have several undesired side-effects. A particularly dangerous side-effect of codeine is the respiration blocking activity. In the last decade efforts have been made to prepare antitussives which in therapeutical doses do not exert this side-effect or possess the side effect only to a very small extent.
As antitussive agents of the above new type certain organic compounds comprising an 1,2,4-oxadiazole ring can be mentioned (e.g. OXOLAMIN and PRENOXDIAZIN).
Recently the group of antitussive agents comprising an 1,2,4-oxadiazole ring has been enriched by a new compound group wherein the 1,2,4-oxadiazole ring is attached to the nitrogen atom in position 7 of the purine structured theophylline through an alkyl chain. In addition to the antitussive effect these compounds exhibit significant respiration improving and broncholytic effect and have a favorable level of toxicity (Hungarian Pat. No. 186,607).
OBJECT OF THE INVENTION
It is the object of the present invention to provide new purine derivatives substituted by an 1,2,4-oxadiazolyl ring which possess stronger therapeutically useful properties than the hitherto known compounds.
DETAILED DESCRIPTION OF THE INVENTION
The above object is achieved by providing new 1,2,4-oxadiazole derivatives of the Formula I as described. It has been found in a surprising manner that the new compounds of the Formula I exhibit an outstandingly strong antitussive effect.
On studying the relationship between chemical structure and therapeutical activity we have come to the unexpected conclusion that in the compounds of the Formula I the purine ring potentiates the antitussive effect of the 1,2,4-oxadiazole moiety to a higher extent than the analoguous derivatives substituted in position 1 by a methyl group.
The compounds of the Formula I differ from the theophylline-oxadiazoles disclosed in Hungarian Pat. No. 186,607 only in the absence of the methyl group on the nitrogen atom in position 1 of the purine ring, the said methyl group being present in the prior art compounds.
The new effect is all the more surprising since the biological activity of theophylline is higher than that of theobromine.
The 1,2,4-oxadiazole ring plays a fundamental role in the outstandingly high antitussive activity as shown by comparative tests carried out with compounds of the Formula II.
Compounds of the Formula II ##STR3## comprise the same purine ring as the compounds of the Formula I but contain no closed 1,2,4-oxadiazole ring. The compounds of the Formula II show practically no antitussive effect.
The antitussive effect of the compounds of the Formula I is so strong that it is higher not only than that of the above mentioned oxadiazole type antitussive agents but also surpasses several times that of codeine.
The further therapeutical advantage of the compounds of the Formula I resides in the favorable level of toxicity.
It is furthermore noteworthy that according to tests carried out on rats and rabbits with the new Formula (I) compounds as opposed to antitussive agents--the compounds of the Formula I exert no respiration blocking effect and moreover have favorable broncho-pulmonal activity.
The aforesaid facts are supported by Table I wherein the ID 50 mg/kg values of 3,7-dihydro-3-methyl-7-[(5-methyl-1,2,4-oxadiazole-3-yl)-methyl]-1H-purine-2,6-dione (the most simple representative of the compounds of the Formula I); two known 1,2,4-oxadiazole-type antitussive agents, codeine and dextromethorphane (morphine type reference compounds) in the alleviation of coughing caused by a 15% citric acid spray are disclosed. The test compounds are added p.o. one hour before the determination of antitussive activity. As test animal guinea pigs are used. (Method: Arzneimittel Forschung 1966, 617-621). Test compound No. 5 is 2-(3-methyl-xanthine-7-yl)-acetamidoxime (a starting material of the Formula II).
It appears from Table I that the absolute strength of the antitussive effect of compound No. 1 is significantly higher than that of reference compounds Nos. 2-4 and 6. The effect of the xanthinyl amidoxime derivative No. 5 is practically negligible.
TABLE I__________________________________________________________________________Alleviation of coughing caused by 15% citric acid spray onguinea pig, the test compounds are administered orally Antitussive effect, measured 1 hourTest Compound Chemical nomenclature after oral administ-No. of test compound ration ID.sub.50 mg/kg__________________________________________________________________________1 3,7-dihydro-3-methy1-(7-(5-methyl- 8.5 l,2,4-oxadiazole-3-yl)-methyl) lH--purine-2,6-dione2 3,7-dihydro-1,3-dimethyl-7-[(5- 111.2(reference methyl-1,2,4-oxadiazole-3-yl)-compound) methyl]-1H--purine-2,6-dione3 3-(2,2-diphenyl-ethane-1-yl)-5- 60.5(reference (-2-piperidino-ethane-1-yl)-l,2,4-compound) oxadiazole.HCl(PRENOXDIAZIN.HCl)4 (ref. Codeine.HCl 65.7compound)5 2-(3-methyl-xanthine-7-yl)- inactive in a acetamidoxime dose of 50 mg/kg p.o.6 (ref. Dextromethorphan 29.0compound)__________________________________________________________________________
The oral antitussive effect of compound No. 1 is very long-lasting, as proved by the data of Table I/A.
TABLE I/A______________________________________Antitussive effect of p.o. administered 3,7-dihydro-3-methyl-7-[(5-methyl-1,2,4-oxadiazole-3-yl)-methyl]-lH--purine-2,6-dioneon coughing induced by 15% citric acid spray on guinea pigPre-treatment time (H) ID.sub.50 mg/kg______________________________________0.5 7.51.0 8.52.0 14.44.0 13.88.0 32.6______________________________________
The acute toxicity of compound No. 1 of Table I and that of reference compounds Nos. 2 and 4 disclosed in Table I/B. Test animal: rats; intraperitoneal administration.
TABLE I/B______________________________________Test compound No. Toxicity on rats(see TABLE I) i.p. LD.sub.50 mg/kg______________________________________1 700.02(reference) 529.74(reference) 72.4______________________________________
Compound No. 1 exhibits not only at oral but also at intravenous administration an outstandingly strong antitussive effect. The said compound decreases in dose-dependant manner (administration: 0.5-8.0 MG/KG I.V.) the coughing caused by mechanical stimulation of the trachea bifurcatio on rabbits narcotised by nembutal. After 2 minutes of I.V. administration the ED 50 value is 2.24 (1.85-2.72) MG/KG calculated according to Lichfield-Wilcoxon. The reference compounds Nos. 4 and 6 possess the same or a somewhat lower antitussive effect. Taking into consideration also the I.O. toxicity data the therapeutical index of the compound No. 1 is ten times more favorable than that of reference compounds Nos. 4 and 6. Other compounds of the Formula I show a similar strong antitussive effect, to that of the compound No. 1 of Table 1.
According to a further aspect of the present invention there is provided a process for the preparation of compounds of the Formula I and pharmaceutically acceptable salts thereof which comprises
(a) reacting an amidoxime of the Formula II ##STR4## (wherein A is as stated above) with a carboxylic acid of the Formula III
R.sup.4 --CO.sub.2 H (III)
(wherein R 4 has the same meaning as R 1 or stands for a group which is suitable for the formation of group R 1 ) or a reactive derivative thereof and if desired converting group R 4 into group R 1 ; or
(b) reacting an amidoxime of the Formula II (wherein A is as stated above) with a carboxylic acid of the Formula III (wherein R 4 is as stated above) or a reactive derivative thereof, subjecting the compound of the Formula IV ##STR5## thus obtained (wherein A and R 4 are as stated above) to cyclization by dehydration after or without isolation and if desired converting group R 4 into group R 1 ; or
(c) reacting an oxadiazole derivative of the Formula V ##STR6## (wherein A and R 4 are as stated above and X stands for halogen or a sulfonic acid ester group ) in the presence of a basic catalyst with 3-methyl-xanthine of the Formula VI ##STR7## or the sodium or potassium salt thereof and if desired converting group R 4 into group R 1 ; or
(d) for the preparation of compounds of the Formula I (wherein A stands for --(CH 2 ) 2 -- and R 1 is as stated above), reacting an olefin of the Formula VII ##STR8## (wherein R 4 is as stated above) with 3-methyl-xanthine of the Formula VI in the presence of a basic catalyst, and if desired converting the group R 4 into group R 1 , and if desired converting a compound of the Formula I thus obtained into a a pharmaceutically acceptable salt thereof.
According to process (a) one may proceed preferably by reacting an amidoxime of the Formula II with an ester of the Formula VIII
R.sup.4 CO.sub.2 R.sup.5 (VIII)
(wherein R 4 is as stated above and R 5 stands for alkyl, preferably methyl or ethyl) in the presence of a base (preferably an alkali or alkaline earth metal hydroxide, carbonate or alcoholate, particularly sodium methylate or sodium ethylate) in a polar or apolar organic solvent and/or diluent under heating, preferably at the boiling point of the solvent and/or diluent. As solvent and/or diluent preferably C 1-4 alcohols, N-alkyl-acid amides (e.g. dimethyl formamide), aromatic hydrocarbons (e.g. benzene, chlorobenzene, preferably toluene or xylene) can be used. If apolar solvents are used, the water and alcohol formed may be advantageously removed by azeotropic distillation.
According to a further preferred form of realization of process (a) an amidoxime of the Formula II is heated with an acid of the Formula III
R.sup.4 --CO.sub.2 H (III)
and/or an anhydride thereof in the presence of an organic solvent. As organic solvent preferably aromatic hydrocarbons can be used. One may proceed particularly preferably by using as solvent the acid and/or acid anhydride whereby the said compounds act simultaneously as acylating and cyclizing agent and as reacting medium. Acylation and cyclization can be carried out at 50°-150° C. particularly at 90°-110° C.
The reaction time of process (a) varies between 30 minutes and 24 hours depending on the reactants and solvent used and the reaction temperature.
According to process (b) acylation may be carried out preferably by using an anhydride of the Formula (R 4 CO) 2 O or an acid halide of the Formula R 4 COX (wherein R 4 is as stated above and X stands for halogen), preferably an acid chloride, in the presence of an organic solvent and/or diluent (e.g. acetone, pyridine, benzene, dimethyl formamide or when anhydrides are used as acylating agent an excess of the acid anhydride preferably dichloromethane, chloroform etc). If acid halides are used, acylation is advantageously carried out in the presence of an acid binding agent. It is preferred to use inorganic acid binding agents (e.g. alkali metal or alkaline earth metal carbonates, such as sodium carbonate, potassium carbonate or calcium carbonate, or hydrogen carbonates eg. sodium hydrogen carbonate etc) but organic acid binding agents (e.g. tertiary amines, such as pyridine or triethyl amine) may be used as well. If acylating agents are used in which R 4 is a basic group, the compound of the Formula IV ##STR9## may also serve as acid binding agent.
According to process (b) the oxadiazole ring is formed in a polar organic solvent and/or water as solvent and/or diluent or in an apolar solvent and/or diluent or in the absence of a solvent by pyrolysis.
Cyclization of the compound of the Formula IV is preferably accomplished at a pH value of 6-8. The said pH is advantageously adjusted by inorganic or organic bases (preferably sodium carbonate or triethyl amine). It is particularly preferred to use a Britton-Robinsom buffer. Cyclization of water soluble compounds of the Formula IV can be preferably carried out in water at pH 7.
According to method (c) a compound of the Formula V ##STR10## (wherein A is as stated above and X stands for halogen or a sulfonic acid ester group ) is reacted with 3-methyl-xanthine of the Formula VI ##STR11## in an organic solvent and/or diluent (preferably dimethyl formamide or an alcohol, preferably n-butanol) in the presence of an inorganic base (e.g. an alkali hydroxide sodium hydroxide preferably, or potassium hydroxide; or an alkali carbonate e.g. sodium or potassium carbonate) or an organic base (e.g. pyridine, triethyl amine or piperidine). One may also proceed by reacting the compound of the Formula V with the sodium or potassium salt of the 3-methyl-xanthine of the Formula VI. The above reactions may be carried out in solution, or suspension, preferably under heating. In the compounds of the Formula Ia ##STR12## thus obtained the R 4 group may be converted, if desired, into an R 1 group.
According to method (d) compounds of the Formula IB ##STR13## (i.e. compounds of the Formula I (wherein A is --(CH 2 ) 2 --) are prepared by reacting a compound of the Formula VII ##STR14## (wherein R 4 is as stated above) with 3-methyl-xanthine in the presence of a basic catalyst, preferably a quaternary ammonium hydroxide, particularly Triton-B in an organic solvent and/or diluent under heating. In the compound of the Formula Ia thus obtained the R 4 group may be transformed, if desired, into the R 1 group.
The 3-methyl-xanthine-7-yl-alkane carboxylic acid amidoximes of the Formula II used as starting material in processes (a) and (b) can be prepared by known methods by reacting the corresponding 3-methyl-xanthine-7-yl-carbonitrile with hydroxylamine under heating in methanol or ethanol or aqueous methanol or ethanol.
The oxadiazoles of the Formula V used as starting material in process (c) can be prepared by methods known per se by reacting the corresponding 3-(w-hydroxyalkyl)-1,2,4-oxadiazole with thionyl chloride, tosyl chloride or mesyl chloride (J. Chem. Res. (M) 1979, 801).
The starting olefins of the Formula VII used in process (d) can also be prepared by known methods (J. Chem. Res. (M) 1979, 801).
Compounds of the Formula Ia and IV, wherein R 1 or R 4 stands for halogenoalkyl, can be prepared from the amidoximes of the Formula II by reacting same with the corresponding halogenoalkane carboxylic acid chlorides in a manner known per se (Hungarian Pat. No. 186,607).
Compounds of the Formula I, wherein R 1 stands for aminoalkyl, can be prepared not only by process (a) but also by subjecting the corresponding compound of the Formula Ia and IV, wherein R 4 is halogenoalkyl, to a substitution reaction, or substitution reaction and cyclization respectively, with the corresponding amine in a manner known per se (Hungarian Pat. No. 186,607).
According to a further aspect of the present invention there are provided pharmaceutical compositions comprising as active ingrdient at least one compound of the Formula I or a pharmaceutically acceptable salt thereof in admixture with suitable inert carriers. The active ingredient can be put up in conventional forms e.g. syrups, tablets, pills, coated pills, dragees, capsules, suppositories, injections etc. The pharmaceutical compositions contain known and generally used solvents, diluents, carriers, excipients etc. The said pharmaceutical compositions are prepared by known methods of pharmaceutical industry.
The active ingredient content of the pharmaceutical compositions according to the present invention amounts to 0.1-100%, preferably 1-30%. The daily dose may be generally 2-2000 mg, depending on the mode of application, the age and body weight of the patient, etc.
SPECIFIC EXAMPLES
Further details of the present invention are to be found in the following Examples without limiting the scope of protection to the said Examples.
EXAMPLE 1
35.0 g (0.25 mole) of 3-methyl-xanthine (Chem. Ber. 83, 209 1950) are dissolved in 81.4 ml (0.25 mole) of a 10% sodium hydroxide solution under shaking; crystallization takes place within some minutes. Water is distilled off in vacuo and the traces of water are removed by azeotropic distillation with toluene. The residue is suspended in 35 ml of dimethyl formamide, whereupon a solution of 18.9 g (0.25 mole) of chloroacetonitrile in 80 ml of dimethyl formamide is added dropwise at 100° C. within 30 minutes. The reaction mixture is stirred at 100° C. for a further hour, filtered until hot, the precipitate (sodium chloride) is washed with hot dimethyl formamide and the united solutions are evaporated to dryness under reduced pressure. The residue is treated with 100 ml of acetone, the crystals are filtered by suction and throughly washed with acetone. The 7-cyanomethyl-3-methyl-xanthine (m.p.: 285°-287° C.) thus obtained can be used in further reactions.
EXAMPLE 2
To a solution of 3.2 g of hydroxylamine-hydrochloride and 36 ml of water 2.5 g of sodium hydrogen carbonate are added in portions. To the solution thus obtained 10.0 g of 7-cyanomethyl-3-methyl-xanthine and 30 ml of ethanol are added, the mixture is stirred at 80° C. for 3 hours. After cooling the precipitated 2-(3-methyl-xanthine-7-yl)-acetamidoxime is filtered by suction and washed with some cold water. Yield 11.0 g, 86%, m.p.: above 320° C.
1 H-NMR(DMSO-d 6 ): 3.55(s, 3H, 3-Me); 4.85(s, 2H, NCH 2 --), 8.03(s, 1H, 8-H); 9.79(s, 1H, N-OH); 11.21(bs, 1H, 1-NH).
EXAMPLE 3
A mixture of a sodium ethylate solution prepared from 6.76 g of metallic sodium and 290 ml of anhydrous ethanol, 35 g of 2-(3-methyl-xanthine-7-yl)-acetamidoxime and 43.0 g of ethyl acetate is heated to boiling under stirring for 4 hours. The hot reaction mixture is filtered, the filtrate is evaporated in vacuo and the residue is dissolved in 200 ml of water. The pH of the solution is adjusted to 7 by adding 10% hydrochloric acid, the precipitate is filtered by suction and crystallized twice from water. Thus, 18.0 g of 3,7-dihydro-3-methyl-7-([5-methyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione are obtained, m.p.: 262°-264° C.
1 H-NMR(DMSO-d 6 ): 2.57(s, 3H, 5-Me); 3.37(s, 3H, 3-Me); 5.66(s, 2H, --CH 2 ); 8.18(s, 1H, 6-H); 11.19(bs, 1H, 1-NH).
EXAMPLE 4
A mixture of 3.76 g of (20 millimoles) of 3-methylxanthine-sodium, 100 ml of dimethyl formamide and 2.60 g (19.6 millimoles) of 3-chloromethyl-5-methyl-1,2,4-oxadiazole is stirred at 100° C. for one hour and a half. The hot reaction mixture is filtered and to the filtrate 50 ml of methanol are added. Thus 3.65 g of 3,7-dihydro-3-methyl-7-([5-methyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione are obtained, m.p.: 262°-264° C. Yield: 69%.
EXAMPLE 5
A solution of 3.7 g of 2-(3-methyl-xanthine 7-yl)acetamidoxime and 45.0 ml of acetic anhydride is stirred at 140° C. for an hour. The cooled solution is diluted with water to tenfold volume, and stirred for 30 minutes. The precipitated O-acetyl-2-(3-methyl-xanthine-7-yl)-acetamidoxime is filtered by suction, and washed with some methanol. Yield 3.6 g, m.p.: above 220° C.
1 H-NMR (DDMSO-d 6 ): 2.01(s, 3H, OAc), 3.34(s, 3H, 3Me), 4.97(s, 2H, NCH 2 --), 6.70(bs, 2H, NH 2 ), 8.07 (s, 1H, 6-H), 11.24 (bs, 1H, 1-NH).
EXAMPLE 6
2.0 g of O-acetyl-2-(3-methyl-xanthine-7-yl)-acetamidoxime are stirred in a mixture of 160 ml of a Britton-Robinson buffer (pH 7) and 200 ml of dimethyl formamide at 95° C. for 6 hours. The reaction mixture is evaporated in vacuo and the residue is crystallized from water. Thus 1.22 g of 3,7-dihydro-3-methyl-7-([5-methyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione are obtained. M.p.: 262°-264° C.
EXAMPLE 7
A solution of 2.38 g of 2-(3-methyl-xanthine-7-yl)acetamidoxime in 40.0 ml of anhydrous acetone is acylated with a solution of 1.13 g of chloroacetyl chloride aand 5.0 ml of acetone in the presence of 0.86 g of sodium hydrogen carbonate. Thus 2.1 g of O-chloroacetyl-2-(3-methyl-xanthine-7-yl)acetamidoxime are obtained. The product is heated at 105° C. and 133 Pa until constant weight for 40 minutes. The residue is crystallized from methanol. Thus 1.6 g of 3,7-dihydro-3-methyl-7-([5-chloromethyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione are obtained.
EXAMPLE 8
(a) A mixture of 1.5 g of 3-([3-methyl-xanthine-7-yl]-methyl)-5-chloromethyl-1,2,4-oxadiazole, 10 ml of diethyl amine and 10 ml of toluene is heated on a water bath under stirring for 8 hours in a closed flask equipped with magnetic stirrer. The mixture is evaporated, washed with water, dissolved in 5 ml of hot ethanol, and clarified with activated charcoal. The hydrochloride salt is formed by adding ethanol containing hydrogen chloride. After crystallization from water 1.4 g of 3,7-dihydro-3-methyl-7-([5-diethylaminomethyl-1,2,4-oxadiazole-3-yl]-methyl)-1-purine-2,6-dione-hydrochloride are obtained.
(b) 1.41 g of O-chloroacetyl-2-(3-methyl-xanthine-7-yl)acetamidoxime prepared according to Example 7 are dissolved in 15 ml of toluene, whereupon 1.5 ml of diethyl amine are added dropwise under vigorous stirring. The reaction mixture is heated to boiling for 8 hours, and evaporated. The residue is washed with water and the hydrochloride salt is formed in ethanol. After crystallization from water 1.2 g of 3,7-dihydro-3-methyl-7-([5-diethylaminomethyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione-hydrochloride are obtained.
(c) A mixture of 2.38 g of 2-(3-methyl-xanthine-7-yl)acetamidoxime 3.0 g of diethylamino acetyl chloride and 20 ml of pyridine is stirred at a temperature not exceeding 20° C., whereupon the reaction mixture is heated on a water bath for 2 hours. The reaction mixture is evaporated, the residue is washed with water and the hydrochloride salt is formed in ethanol. After crystallization from water 2.1 g of 3-([3-methyl-xanthine-7-yl]methyl)-5-diethylaminomethyl-1,2,4-oxadiazole-hydrochloride are obtained.
(d) A mixture of 2.38 g of 2-(3-methyl-xanthine-7-yl)acetamidoxime, 200 ml of toluene, 1.36 g of sodium ethylate and 3.46 g of ethyl-β-diethyl-amino-propionate is heated to boiling under stirring in a flask equipped with a water separator for 12 hours. The reaction mixture is evaporated in vacuo, the pH is adjusted to 7, the precipitate is washed with water, dried and the hydrochloride salt is formed in ethanol. Thus 2.0 g of 3,7-dihydro-3-methyl-7-[(5-diethylaminomethyl-1,2,4-oxadiazole-3-yl)-methyl]-1H-purine-2,6-dione-hydrochloride are obtained.
EXAMPLE 9
A solution of 2.38 g of 2-(3-methyl-xanthine-7-yl)acetamidoxime in 25 ml of ethanol is admixed with a solution of 0.46 g of metallic sodium in 25 ml of ethanol and 3.02 g of ethyl cyclohexane carboxylate. The reaction mixture is heated to boiling under stirring for 10 hours, then evaporated. The residue is admixed with water and the pH is adjusted to 7. The precipitate is crystallized from aqueous ethanol. Thus 2.51 g of 3,7-dihydro-3-methyl-7-([5-cyclohexyl-1,2,4-oxadiazole-3-yl]methyl)-1H-purine-2,6-dione are obtained, m.p.: 245°-248° C.
EXAMPLE 10
238 g of 2-(3-methyl-xanthine-7-yl)-acetamidoxime are reacted with 3.28 g of ethyl phenyl acetate and sodium ethylate in ethanol in an analogous manner to the preceeding Example. Thus 2.7 g of 3,7-dihydro-3-methyl-7-([5-benzyl-1,2,4-oxadiazole-3-yl]-methyl)-1H-purine-2,6-dione are obtained, m.p.: 188°-190° C.
EXAMPLE 11
A mixture of 2.52 g of 3-(3-methyl-xanthine-7-yl)propionic acid amide oxime, 4.0 ml of ethyl acetate and a solution of 0.46 g of metallic sodium in 25 ml of ethanol is heated to boiling under stirring for 5 hours. The hot reaction mixture is filtered and the filtrate is evaporated. The residue is treated with 20 ml of water, the pH is adjusted to 7 and the precipitated product is crystallized from water. Thus 1.7 g of 3.7-dihydro-3-methyl-7-(2-[5-methyl-1,2,4-oxadiazole-3-yl]-ethane-1-yl)-1H-purine-2,6-dione are obtained, m.p.: 258°-260° C.
EXAMPLE 12
A mixture of 2.52 g of 3-(3-methyl-xanthine-7-yl)propionic acid amidoxime, 25 ml of toluene, 1.12 g of powdered potassium hydroxide and 3.70 g of ethyl-β-piperidino-propionate is heated to boiling under stirring under a water separator for 10 hours. The reaction mixture is evaporated, the residue is treated with water, the pH is adjusted to 7, the precipitated product is washed with water and converted into the hydrochloride salt in ethanol. Thus 2.6 g of 3,7-dihydro-3-methyl-7-{2-(5-[2-piperidino-ethane-1-yl]-1,2,4-oxadiazole-3-yl)-ethane-1-yl}-1H-purine-2,6-dione-hydrochloride are obtained.
EXAMPLE 13
A mixture of 2.66 g of 4-(3-methyl-xanthine-7-yl)-butyric acid amidoxime, 4.0 ml of ethyl acetate and a solution of 0.46 g of metallic sodium in 25 ml of ethanol is heated to boiling for 6 hours. The reaction mixture is worked up as described in Example 3. Thus 1.8 g of 3,7-dihydro-3-methyl-7-(3-[5-methyl-1,2,4-oxadiazole-3-yl]-propane-1-yl)-1H-purine-2,6-dione are obtained.
EXAMPLES 14-34
The compounds enumerated in Table II are prepared in an analogous manner to Examples 1-13. In the said Table II the No. of the Example, the definition of symbols A and R 1 and reference to the method are disclosed.
TABLE II______________________________________No.ofEx- Methodam- (No. ofple A R.sup.1 Example)______________________________________14 CH.sub.2 CH.sub.3 CH.sub.2 315 CH.sub.2 CH.sub.3 CH.sub.2 CH.sub.2 316 CH.sub.2 CH.sub.3 (CH.sub.2).sub.3 317 CH.sub.2 CH.sub.3 (CH.sub.2).sub.4 418 CH.sub.2 (CH.sub.3).sub.2 CH 319 CH.sub.2 HOCH.sub.2 CH.sub.2 320 CH.sub.2 ##STR15## 821 CH.sub.2 ##STR16## 822 CH.sub.2 ##STR17## 323 CH.sub.2 (CH.sub.2).sub.3 COOH 324 CH.sub.2 ##STR18## 325 CH.sub.2 ##STR19## 326 CH.sub.2 ##STR20## 627 CH.sub.2CH.sub.2 (C.sub.2 H.sub.5).sub.2 NCH.sub.2 828 CH.sub.2CH.sub.2 ##STR21## 829 CH.sub.2CH.sub.2 (C.sub.2 H.sub.5).sub.2 N(CH.sub.2).sub.2 830 (CH.sub.2).sub.3 (C.sub.2 H.sub.5).sub.2 N(CH.sub.2).sub.2 831 (CH.sub.2).sub.3 ##STR22## 832 (CH.sub.2).sub.4 CH.sub.3 433 (CH.sub.2).sub.4 (C.sub.2 H.sub.5).sub.2 N(CH.sub.2).sub.2 834 (CH.sub.2).sub.4 ##STR23## 8______________________________________
EXAMPLE 35
(a) Tablets
______________________________________Component Amount, g______________________________________3-[(3-methyl-xanthine-7-yl)-methyl]- 10.05-methyl-1,2,4-oxadiazoleWheat starch 130.0Calcium phosphate 199.0Magnesium stearate 1.0Total weight 340.0______________________________________
The above components are admixed, the powdered mixture is pressed to 100 tablets, weighing 340 mg each, in a manner known per se. Each tablet contains 10 mg of the active ingredient.
(b) Dragees
______________________________________Component Amount, g______________________________________3-[(3-methyl-xanthine-7-yl)-methyl]- 50.05-methyl-l,2,4-oxadiazoleCarboxymethyl cellulose 300.0Stearic acid 20.0Cellulose acetate phthalate 30.0Tota1 weight 400.0______________________________________
A mixture of the active ingredient, carboxymethyl cellulose and stearic acid is thoroughly admixed with a solution of the celulose acetate phthalate in 200 ml of ethyl acetate. From this mixture dragees weighing 400 mg are pressed and the core is coated with 5% aqueous polyvinyl pyrrolidone in a known manner. Each dragee contains 50 ml of the active ingredient.
(c) Syrup
______________________________________Component Amount, g______________________________________3-(3-[3-methyl-xanthine-7-yl]- 5 gpropane-1-yl)-5-(2-diethylamino-ethane-1-yl)-1,2,4-oxadiazole-hydrochlorideLemon Syrup 200 mlBenzoic acid solution 20 mlWater 100 mlSugar syrup ad 1000 ml______________________________________
The active ingredient is dissolved in water with warming, whereupon 500 ml of sugar syrup and the other components are added and the mixture is filled up to 1000 ml with sugar syrup. The active ingredient content of the syrup amounts to 5 mg/ml. | The invention relates to new oxidiazole-alkyl-purine-derivatives of the Formula I ##STR1## and pharmaceutically acceptable salts thereof wherein A stands for C 1-4 alkylene and
R 1 represents C 1-6 alkyl, hydroxyalkyl, halogenoalkyl, carboxyalkyl, C 5-6 cycloalkyl or aminoalkyl of the Formula --(CH 2 ) n --NR 2 R 3 in which group n is an integer 1-3; R 2 and R 3 each stand for hydrogen or C 1-4 alkyl or together with the adjacent nitrogen atom they are attached to form a 5- or 6-membered nitrogen containing heterocyclic ring which may optionally comprise a further nitrogen atom or an oxygen atom as heteroatom; or
R 1 stands for phenyl, hydroxyphenyl, carboxyphenyl, benzyl or dimethoxybenzyl
The compounds of the Formula I can be prepared by methods known per se and can be used in therapy as antitussive agents. | 2 |
This is a continuation of application Ser. No. 293,512, filed Aug. 17, 1982, now abandoned and the benefits of 35 USC 120 and claimed relative to its.
BACKGROUND OF THE INVENTION
This invention relates to a method of producing nonwoven fabrics not substantially comprising openings through a treatment with high velocity water streams. More particularly, the invention relates to an improvement in a method of producing nonwoven fabrics wherein a fibrous web (or a batt: this interchangeability of term applies to all of the same term, fiber web, appearing in the following statements) is treated on a water impermeable supporting member with water jet streams ejected from a nozzle.
In a conventional method of producing nonwoven fabrics of the type wherein configuration of nonwoven fabrics is maintained by an individual fiber entanglement carried out through a treatment with water jet streams, two methods are available with reference to selection of a member for supporting the fibrous web in the water jet streams treatment: one being a method wherein a water permeable supporting member consisting of a porous screen or of a porous plate is employed; the other being a method wherein a water impermeable supporting member consisting of a roll or of a plate is employed.
Under the method of employing the water permeable supporting member, since the water jet streams ejected onto the fibrous web pass through the supporting member, draining treatment of the water streams can be easily made and the fibrous web may be treated with good stability.
However, the water streams still are of a considerable pressure even after passing through the fibrous web and the supporting member, no effective utilization of energy of the water streams in the entangling treatment is provided. Such tendency increases particularly in proportion to the decrease in the weight of the fibrous web per square meter and affects the efficiency. Accordingly, under the method of employing the water permeable supporting member, neither improvement in the production speed nor reduction in the production costs can be attained. Furthermore, since this method necessitates the treatment with extremely high pressure of water jet streams, large scale production facilities are involved and is therefore not economical.
Under the method of employing the water impermeable supporting member, water jet streams ejected onto the fibrous web pass through the fibrous web, collide with the surface of the supporting member and are converted into rebound streams to act again, provided that the question of the draining treatment is effectively resolved, wherefore the fiber entanglement can effectively be carried out by an interaction between the jet streams and the rebound streams. Accordingly, this method does not accompany the disadvantages as seen in the method of employing the water permeable supporting member discussed above. It is to be noted, however, that since the water streams do not permeate through the supporting member under the method of employing the water impermeable supporting member a question as to how the draining treatment should be made remains; in the case where the draining is not carried out sufficiently, fibers float in the water and said fibers are acted upon by the jet streams whereby the energy of the jet streams is sharply diminished, entangling treatment of the fibers is hindered, the fibrous web is caused to be disarranged and the stability in the treatment thereof is lost. For these reasons, the method discussed does not make it possible to provide nonwoven fabrics with superior property. In this connection, employment of a roll, a curved plate, a grooved plate or the like as a water impermeable supporting member have heretofore been proposed but a mere selection of such member does not ably overcome the problems. None of the conventional literature regarding the method of employing the water impermeable supporting member discloses concrete measures to effectively solve the various problems discussed above. In fact, the method of employing the water impermeable supporting member has not yet been successfully put into industrial practice, so far as the inventors of the present invention know.
Accordingly, the basic object of the present invention resides in the provision of a method of producing whereby various problems discussed above can effectively be overcome and a nonwoven fibrous sheet with superior property can industrially be produced in large quantity. Other objects will be understood from the following statements.
In order to attain the above object, the present invention provides a method of producing nonwoven fabrics wherein: in a method of producing nonwoven fabrics wherein a fibrous web is guided onto a water impermeable supporting member and said fibrous web is subjected to water jet streams ejected from the nozzles which are arranged with intervals in a manner to face the surface of said fibrous web and to run across the width thereof whereby entangling treatment of individual fibers of said fibrous web is carried out; the improvement which comprises employing a fibrous web weighing from 15 to 100 g/m 2 as said fibrous web, guiding said fibrous web onto a first supporting member consisting of a smooth-surfaced water impermeable endless belt, carrying out a preliminary entangling treatment with the water jet streams ejected from said nozzles arranged with respect to said first supporting member, guiding said fibrous web entangled to a certain degree through said preliminary entangling treatment onto each of second supporting members consisting of a plurality of smooth-surfaced water impermeable rolls disposed with intervals, and carrying out said entangling treatment with the water jet streams ejected from said nozzles each arranged with respect to each of said second supporting members.
According to the present invention, treatment of the fibrous web is carried out with a ejection of the water jet streams on the second supporting member consisting of a plurality of water impermeable rolls multistagedly and parallely arranged in order to provide effective draining treatment and to obtain nonwoven fabrics with superior property. It is to be noted, however, that originally the fibrous web is formed with a slight entanglement of fibers and the configuration thereof which is maintained only with such mere entanglement may be liable to distortion or breakage even with minor external force. Accordingly, it may happen that when the fibrous web is guided onto the initial water impermeable roll for treatment, it is damaged by the water jet streams drained in front and in the rear of the roll and the treatment thereof becomes impossible. For this reason, preliminary entangling treatment is arranged to be carried out on the first supporting member consisting of a water impermeable belt which is capable of supporting the fibrous web with good stability, whereby necessary strength to transfer toward the said roll is provided.
In the entangling treatment of the fibers with ejection of the water jet streams on said belt and on each of said rolls which are to function as a water impermeable supporting member for the fibrous web, it happens that, where draining treatment is insufficient, the fibers floating in the water are acted upon by the water jet streams whereby energy of the water jet streams is sharply diminished, entangling treatment of the fibers are hindered, the fibrous web is caused to be disarranged and the stability in the treatment thereof is lost, as discussed previously. For this reason, in a preferred embodiment, an arrangement is made so that an average quantity of supply of water in a direction of width to be ejected onto each water impermeable supporting member is less than 400 cc/sec.cm, more preferably less than 30 cc/sec.cm. An average quantity of supply of water in a direction of width, referred to above, indicates the value obtained through F/w where F corresponds to a total flow quantity ejected into a single water impermeable supporting member and W corresponds to the effective width of nozzles on said supporting member. Where such value is more than 40 cc/sec.cm, it is not possible to obviate the disadvantageous situation or result mentioned above.
In a preferred embodiment, jet pressure of the water jet streams is less than 35 kg/cm 2 , more preferably 15 to 30 kg/cm 2 and where such pressure is more than 35 kg/cm 2 , movement of individual fibers within the fibrous web becomes great and thereby the fibrous web is caused to be in disorder and to be uneven in the fiber entanglement whilst where the pressure is less than 7 kg/cm 2 , no effective production of nonwoven fabrics with superior property is possible, howsoever a long time treatment is carried out with respect to the fibrous web or the nozzles are brought close to the fibrous web to the extent that they nearly get in touch with the fibrous web.
The water jet streams are ejected from the nozzles. Types of the nozzles to be employed for this purpose are: for example, a nozzle of the type wherein plural jet holes are formed in a pipe at regular intervals, a nozzle of the type wherein jet holes are formed in a basic plate at regular intervals and the basic plate with such construction is incorporated into, for instance, a distributing pipe, or the like. In a preferred embodiment, the vertical cross section configuration of the jet holes of the nozzle consists of a portion with a gradually reduced diameter toward the jet holes and a portion with a small diameter extending straightforwardly in order that the resistance of water streams relative to the jet holes is lessened and the loss of pressure toward the jet holes is diminished, wherein where the length of the latter portion is supposed to be L and the diameter thereof is supposed to be D, the ratio L/D is set to be less than 4/1 or preferably less than 3/1. In case where the former portion is not of the configuration mentioned above and the ratio L/D is set to be more than 4/1, straightforward transferability of the water streams from the jet holes is equal to the case wherein said ratio L/D is set to be less than 4/1. Since, however, the resistance of water streams increases, the loss of pressure toward the jet holes becomes large. Further, the configuration of the water jet streams represents columnar streams of water the diameter of the jet holes is arranged to be 0.05 to 0.2 mm and the nozzles comprise the jet holes with intervals from 0.5 to 10 mm.
It is necessary that the belt and the individual rolls referred to above as the water impermeable supporting member for fibrous webs should be of hard surfaces sufficient enough to prevent that energy of the water jet streams is adsorbed by the deformation of the supporting members and thereby the efficiency in the fiber entanglement is lowered. In a preferred embodiment, the hardness of surface is set to be more than 50°, more preferably over 70°, according to the regulation of K6301Hs under JIS(Japanese Industrial Standard). As far as such hardness is maintained, metal, rubber, plastic and the like may be used solely or in combination to provide a multiple construction.
As the fibrous web, any one of the conventional fibers used generally in the past for the production of woven fabrics, nonwoven fabrics or the like may be used. As the web configuration, any type of random, parallel, cross web or the like may be employed. However, since the present invention is directed to a method employing a water impermeable supporting member, a fibrous web of the type with weight of 15 to 100 g/m 2 , preferably 20 to 60 g/m 2 is used, such that energy of the water jet streams may efficiently be provided for the fibrous web. Where such weight is less than 15 g/m 2 , irregularity of the fibrous web occurs and nonwoven fabrics with substantial uniformity can not be obtained. Where such weight is more than 100 g/m 2 , sufficient effect to be enjoyed by the use of the water impermeable supporting member can not be obtained. In a preferred embodiment, a random web formed by a card provided with at least one condensing roll which is arranged between a doffer and a comber in such a manner that the circumferential surface speed is substantially lower than that of the doffer, is used as the fibrous web. With the employment of this random web, it is possible to provide a nonwoven fabric which has no difference in its lengthwise or crosswise tenacity, the fibers of which are oriented in three dimensional direction and which is richer in its bulkiness than the web obtainable from a conventional random card.
According to the method of the present invention, draining treatment can be sufficiently carried out. Since various problems involved in the method of using the water impermeable supporting member as explained above can all be resolved, efficient treatment of the fibrous web with water jet streams can be made and hence desired objects may be attained. The nonwoven fabrics obtained through the method according to the present invention do not substantially comprise openings and the fibers are intricately and firmly entangled in three dimensional direction. Accordingly, the nonwoven fabrics provided by the present invention are superior in tensile strength bulkiness and flexibility. This means that the nonwoven fabrics provided by the present invention are of excellent suitability as a constitutional element of sanitary goods, particularly such as sanitary napkins, disposable diapers or the like which are used in contact with the human body and humors. It is also possible to employ the nonwoven fabrics by the present invention for a wide variety of fields of general goods covering such as industrial filter, a wiper, a pillow case or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention can be more thoroughly understood by the following discussion, with reference to the drawings, wherein:
FIG. 1 shows a side elevation to illustrate the state wherein fibers are subjected to a water jet stream on a roll which is employed as a water impermeable supporting member used in the method according to the present invention;
FIG. 2 is a perspective view to show how a nozzle is arranged on a roll which is employed as a water impermeable supporting member used in the method according to the present invention;
FIGS. 3 and 4 perspective views to show how a nozzle is arranged on an endless belt which is employed as another water impermeable supporting member used in the method according to the present invention;
FIG. 5 is a schematic side elevation showing one example of an apparatus to carry out the method according to the present invention;
FIG. 6 is a schematic side elevation of a card forming a fibrous web used in the method according to the present invention;
FIG. 7 is a schematic enlarged plan view of the nonwoven fabrics obtained by the method according to the present invention;
FIGS. 8(a)-(d) show vertical cross-sectional views of some examples of nozzle jet holes which are used in the method according to the present invention; and
FIGS. 9 (a) and (b) show enlarged schematic cross-sectional views cut in thick direction of sheet-like products consisting of foamed sheets with soft elasticity in the surface and the inside of which fibers are planted.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, reference numeral 1 designates a typical smooth-surfaced roll employed as a water impermeable supporting member, wherein a fibrous web 3 is acted upon by water jet streams 2 against the the roll 1. The water jet streams 2 first passes through the fibrous web 3 and then rebound from the surface of the roll 1, as indicated by an arrow 4, acting again on the fibers to provide entanglement thereof. Accordingly, the fibrous web 3 is treated by an interaction between water jet streams and rebound streams. As a consequence, individual fibers of the fibrous web 3 are caused to move in three-dimensional direction whereby intricate and rigid entanglement may effectively be carried out. Water streams, their energy having them lost through the fiber entanglement, are drained partly from the circumferential surface of the roll 1 as indicated by arrows 5 and partly along the moving fibrous web. Although the treatment of the fibrous web on a smooth-surfaced endless belt employed as another water impermeable supporting member is not shown in the drawings, it is to be understood that the fibrous web is acted upon by the water jet streams in exactly the same manner as in the case of the roll 1. Water streams, which have lost their energy on the belt, are drained partly from the circumferential edges of the belt and partly along the moving fibrous web.
FIG. 2 shows the situation wherein a nozzle 7 is arranged on a roll 6 employed as the water impermeable supporting member. FIG. 3 shows the situation wherein a nozzle 11 is arranged over a smooth-surfaced endless belt 10 employed as another water impermeable supporting member and which is suspended between rolls 8 and 9. The roll 6 and the belt 10 consist solely of metal, rubber or plastic or of a multiple construction containing these materials in a combined state, the surface hardness thereof being more than 50°, preferably over 70°, according to the regulations of K6301Hs under JIS(Japanese Industrial Standard). The diameter of the roll 6 is 50 to 300 mm. The nozzles 7, 11 are of the construction wherein jet holes, each being of a diameter 0.05 to 0.2 mm, are provided at regular intervals along the center of the lower surface. Such construction of the nozzles may alternatively be that wherein jet holes are formed in a basic plate at regular intervals and the basic plate with such a structure is incorporated into a distributing pipe or the like. Water jet streams 12, 13 ejected from the nozzles 7, 11 represent columnar streams and are arranged to be ejected perpendicularly with respect to the roll 6 and the belt 10. Jet holes of the nozzles 7, 11 consist of a portion with a gradually reduced diameter 48 toward ejection openings and a portion with a small diameter extending straightforwardly 49, as will be seen from FIGS. 8 (a), (b) and (c) covering vertical cross sections of the jet holes, the ratio L/D between the length L and the diameter D of the portion 49 being set to be less than 4/1, preferably less than 3/1. Due to such configuration of the jet holes of the nozzle and the ratio L/D which is set to be less than 4/1, the resistance of water streams relative to the jet holes is lessened and the loss of pressure toward the jet holes is diminished. Supposing that the vertical cross section of the jet holes represents a cylindrical configuration being of same diameter and the said ratio L/D is set to be more than 4/1, straightforward transferability of water streams from the jet holes is equal to the case wherein said ratio L/D is set to be less than 4/1, whilst resistance of water streams increases and the loss of pressure toward the jet holes becomes large. Where the straightforward transferability of the water streams is bad, entangling treatment of the fibers of the fibrous web cannot effectively be carried out and where said loss of pressure is large, considerable economic disadvantage results. The average quantity of supply of water jet streams in a direction of width to be ejected onto each of the roll 6 and the belt 10 is less than 40 cc/sec.cm, preferably less than 30 cc/sec.cm and where a row of the nozzles 7, 11 is disposed on the roll 6 and the belt 10, as shown in FIGS. 2 and 3, said average quantity of supply of liquid jet streams is determined by: said quantity of supply (cc/sec.cm)=F (quantity of flow from the nozzle 7 or 11)/W(effective width of the nozzle 7 or 11). Where two rows of the nozzles 14, 15 are disposed on the belt 10, as shown in FIG. 4, determination is made on the basis of: said average quantity of supply in a direction of width (cc/sec.cm)=F 1 (quantity of flow from the nozzle 14)+F 2 (quantity of flow from the nozzle 15)/W(effective width of the nozzles 14, 15). Where said quantity of supply which is determined by said F/W is more than 40 cc/sec.cm, drainage of the water jet streams to be ejected onto the roll 6 and the belt 10 becomes insufficient, whereby the energy of the water jet streams is sharply diminished, the efficiency in the fiber entanglement is affected, the fibrous web is caused to be in disorder and, hence, the stability in treatment is damaged.
FIG. 5 shows one embodiment of an apparatus in order to exercise the method according to the present invention. In this apparatus, the endless belt and the roll which are employed as the water impermeable supporting member shown in FIGS. 2 and 3 are incorporated, wherein numeral 16 is the belt and indicated by reference numerals 17a, 17b and 17c are the rolls. The belt 16 is suspended between the rolls 18 and 19. The rolls 17a, 17b 17c appear in the upper left portion of the drawings, relative to the belt 16. Further, the nozzles of the type as shown in FIGS. 2 and 3 are incorporated in the apparatus. These nozzles are designated by reference numerals 20a, 20b and are disposed above the belt 16, the rolls 17a, 17b and 17c. Designated by a reference numeral 22 and shown in the upper left portion of the roll 17c is a pair of squeezing rollers to squeeze moisture of the fibrous web 21. Each of the nozzles 20a, 20b is connected to a distribution tank 25 via a pressure regulating valve 23 and a pressure gauge 24. The distribution tank 25 is connected to a filter tank 27 via a pipe 26. The filter tank 27 is connected to a pressure pump 29 designed to be driven by a motor 28. The pressure pump 29 is connected to a tank 31 via a pipe 30. Meanwhile a dish-like recovery tank 32 is disposed in the lower surface area of the belt 16, the rolls 17a, 17b, 17c and the squeezing rollers 22. The recovery tank 32 is connected to a tank 31 via a pipe 33 and a filter box 34.
According to such apparatus as explained above, water contained in the tank 31 is subjected to pressure by the high pressure pump 29, filtered by the filter tank 27, conveyed to the distribution tank 25 and then distributed to each of the nozzles 20a, 20b whereby water streams with ejection pressure of from 7 to 35 kg/cm 2 and with an average quantity of supply in a direction of width less than 40 cc/sec.cm are ejected from each of the nozzles 20a, 20b onto the belt 16 and onto each of the rolls 17a, 17b, 17c. Accordingly, while the fibrous web 21 with weight of 15 to 110 g/m 2 is guided from the direction indicated by an arrow 35 onto the belt 16 and toward the direction indicated by an arrow 36 passes over the intervals between the belt 16 and the adjacent rolls 17a, 17b, 17c, preliminary entangling treatment is given to the fibrous web on the belt 16 by high pressure water streams ejected from the nozzle 20a, power of such preliminary entangling treatment being in a degree that the fibrous web 21 may not be subjected to distortion or damage by the drainage of the high pressure streams of water ejected from each of the nozzles 20a, 20b. The fibrous web 21 treated to a certain degree through such preliminary entangling treatment is then guided onto each of the rolls 17a, 17b, 17c so as to be subjected to a gradual and regular entangling treatment by the high pressure water streams ejected from each of the nozzles 20b, whereafter the fibrous web 21 is conveyed to the rollers 22 to squeeze almost all the moisture out before being further transferred to a drying process (not shown). The drainage from the belt 16 and from each of the rolls 17a, 17b, 17c and the squeezing rollers 22 is arranged to fall into the recovery tank 32 so as to be recovered thereby, subjected to filtration by the filter box 34 before being further conveyed to the tank 31.
FIG. 6 shows a preferred card to form a preferred fibrous web to be employed in the method according to the present invention. This card comprises an arrangement wherein in a mechanism of an ordinary card having a cylinder 37, a doffer 38, a comber 39, a worker 40, a stripper 41 and a taker-in roller 42; a condensing roll 43 having substantially the same circumferential surface structure as that of the doffer 38 is disposed between the doffer 38 and the comber 39, circumferential surface speed of the condensing roll 43 being designed to be substantially lower than that of the doffer 38. With the employment of such card, it is possible to arrange that the fibrous web 44 is contracted in its direction of flow by a cooperative action between the doffer 38 and the condensing roll 43 and the fiber thereof is accumulated. Accordingly, the fibrous web formed with this card represents a randomized configuration, it being extremely rich in its bulkiness and not having so much lengthwise and crosswise vectorial difference. Although FIG. 6 illustrates an arrangement wherein one condensing roll 43 is provided, it is possible to arrange that two condensing rolls are disposed in opposite direction. Such arrangement of providing two condensing rolls is found to be preferable for obtaining good results in condensing treatment.
FIG. 7 shows a schematic enlarged plan view of the nonwoven fabric obtained by the method according to the present invention. This nonwoven fabric designated by a reference numeral 45 comprises a longitudinal stripe pattern in which a stripe portion 46 with high density and a stripe portion 47 with low density are arranged reciprocally in the direction of width. Entangling state of fibers of the nonwoven fabric 45 is that the stripe portions 46, 47 are reciprocally bent, twisted and entangled in the three-dimensional direction with intricacy and ridigness wherein the stripe portion 46 represents a tuft-like and a rib-like configuration having loose ties and the stripe portion 47 represents a groove-like and a valley-like configuration. Width of the stripe portions 46, 47 and the intervals therebetween may optionally be changed by the dimensions of the jet holes for the water jet streams and by the arrangement of intervals of such jet holes. The stripe portions 46, 47 will appear more distinctively where a parallel web is used as the material for the nonwoven fabric 45 while where a random web is used, no such clear appearance of the stripe portions is available. In case where it is required that superior tension of the nonwoven fabric is provided, use of a random web, particularly use of the random web of the type formed through the card shown in FIG. 6 is advisable. The nonwoven fabric obtained in this way is rich in its bulkiness and is superior in its elasticity.
FIGS. 9 (a), (b) show a sheet-like product wherein fibers 52 are planted in a foamed sheet having soft elasticity 51. Such product 50 may be produced by the apparatus shown in FIG. 5. In this case, the soft elastic foamed sheet 51 is disposed under the lower surface of the said fibrous web 52 and the high speed streams of water are ejected thereon in a manner already explained. However, since the foamed sheet 51 has elasticity to absorb energy of the water jet streams, it is preferable to arrange that the thickness of the sheet 51 is less than 5 mm and the ejection pressure of the water jet streams is more than 35 kg/m 2 . The sheet-like product 50 obtained in this way represents an external appearance like a flocked sheet wherein the fibrous web 52 is entangled in the surface and in the inside of the foamed sheet 51.
EXAMPLE 1
This example shows that in the method according to the present invention, the water impermeable supporting member, average supply quantity of water jet streams in a direction of width on said supporting member, ejection pressure and the hardness of surface of said supporting member are extremely important. In this example, a random web with weight of about 40 g/m 2 consisting of a rayon staple fiber with fineness of 15 denier and with fiber length of 51 mm is guided into the apparatus of the type as shown in FIG. 5 for jet treatment and thereafter subjected to drying at a normal temperature (room temperature). Property of the sample obtained in this way is shown in Table 1. The diameter of jet hole of the nozzle in the apparatus referred to above was 0.12 mm. In order to obtain a comparative sample, said fibrous web was guided onto an endless belt which works as a water permeable supporting member and which consists of a wire gauge with wire diameter of 0.046 mm and with mesh of 20 and treatment was made by said nozzle in the same manner as mentioned above. The sample obtained in this way was found to be of openings. Additional experiment was carried out under the condition that the nozzle 20a shown in FIG. 5 is closed and the fibrous web is subjected to treatment in the same manner as mentioned above without preliminary treatment on the belt 16. The result was that the fibrous web was damaged by drainage in the space between the rolls 17a and 18 and continuous treatment of the web became impossible.
EXAMPLE 2
This example shows that the weight of the fibrous web per square meter is important in the method according to the present invention. As an apparatus for treatment by water jet streams, the apparatus of the type shown in FIG. 5 was used. Parallel web consisting of acrylic fabric with 1.2 denier fineness was guided onto a stainless roll having hardness of 100° provided under the regulations of JIS (Japanese Industrial Standard)--K6301Hs and then subjected to jet treatment with water jet streams ejected from the nozzle having jet orifices with diameter of 0.13 mm at a jet pressure of 30 kg/cm 2 and with average supply quantity of liquid of 20.5 cc/sec.cm in the direction of width and, as a result, a sample as shown in FIG. 7 was obtained.
TABLE I__________________________________________________________________________ Average supply Jet quantity in TensileSupporting member pressure direction of width Weight strengthNo. material hardness (Kg/cm.sup.2) (cc/sec · cm) (g/m.sup.2) (Kg/2.5 cm) Remarks__________________________________________________________________________1 stainless 100 7 20.5 38.7 0.22 stainless 100 20 3.2 36.2 1.53 stainless 100 30 8.4 39.2 3.74 stainless 100 30 32.1 38.5 2.1 Web disordered due to nearly flooded state5 stainless 100 30 40.2 -- -- Web destroyed due to flood state6 stainless 100 40 12.8 32.3 3.2 Disorder of web appears7 hard 72 30 8.4 39.3 2.1 rubber8 soft 45 30 8.4 40.1 1.1 rubber9 Comparison product 30 8.4 41.2 1.610 50 30.5 38.5 2.2__________________________________________________________________________ Note: Tensile strength in direction of MD
TABLE II______________________________________ Tensile strengthNo. Weight (g/m.sup.2) (g/cm//g/m.sup.2)______________________________________1 12.5 25.4 Opening appears in2 30.0 52.1 sheet and fibers3 50.0 52.8 disordered4 80.0 40.15 120.0 21.5______________________________________ Note: Tensile strength noted in the above Table corresponds to a value obtained in such a manner that the numerical value measured by a tension tester with regard to a tensile strength of a sample strip is divided by the weight and width of the sample.
EXAMPLE 3
This example shows that the ratio L/D between the length L of the straightforwardly extending small diameter portion 49 and the diameter D of the jet hole of the nozzle shown in FIG. 8 is important in the method according to the present invention. In this example, the nozzle of the type having the jet hole with configuration and with diameter of 130° as shown in FIG. 8(a) was employed and the water was ejected at a jet pressure of 30 kg/cm.sup.. The following table shows the result of measurement of flow quantity wherein nozzles each being of ratio different from the above mentioned ratio was employed.
TABLE III______________________________________ Flow quantityNo. D(μ) L(μ) L/D unit (cc/min. hole) Remarks______________________________________1 130 0 0 59.2 Straightforward transferability of liquid streams slightly poor2 130 200 1.5 57.8 Straightforward transferability of liquid streams good3 130 390 3.0 52.4 Straigtforward transferability of liquid streams good4 130 350 4.2 41.0 Straightforward transferability of liquid streams good but flow quantity thereof unsufficient______________________________________
EXAMPLE 4
This example shows that since the random web is of small strength ratio difference in its lengthwise and crosswise tenacity, such is preferable to be employed as a treatment web to obtain a nonwoven fabric with superior property through the method according to the present invention. In this example, an apparatus of the type as shown in FIG. 5 was used; a parallel web and a random web comprised of a polyester fiber with fineness of 1.4 denier and with fiber length of 38 mm were treated and dried under the condition that a hard rubber belt and a stainless roll having hardness of 100° prescribed under the provisions of JIS (Japanese Industrial Standard)--K6301Hs are used as a water impermeable supporting member; jet pressure of the nozzle is 30 kg/cm 2 ; average supply quantity of water streams is 8.3 cc/sec.cm; and the ratio L/D between the length L of the straightforwardly extending small diameter portion of the nozzle and the width D thereof is 1.5/1. Property of the sample obtained in this manner is as appears in the following table. The parallel web explained above is the one formed by a normal card comprising no condensing roll and the random web also explained above is the one formed by the card having a condensing roll and appearing in FIG. 6.
TABLE IV______________________________________ Lengthwise & Web Weight crosswise Specific volumeNo. configuration (g/m.sup.2) strength ratio (cm.sup.3 /g)______________________________________1 parallel 35.6 18.1:1 7.22 random 35.2 6.2*1 9.3______________________________________ (Note) Specific volume: Observed fiber volume per 1 g
EXAMPLE 5
This example shows the manufacturing of a product of the type wherein a fiber is planted in a soft elastic foamed sheet. In this example, an apparatus of the type as shown in FIG. 5 was used. A parallel web with weight of 20 g/m 2 consisting of a rayon fiber with fineness of 3 denier and with fiber length of 70 mm was piled on a polyurethane foamed sheet with thickness of 1 mm and subjected to treatment. The resultant product was found to be of the structure wherein a fiber is planted and entangled in the surface and in the inside of the foamed sheet. Further, expansibility of such product was not damaged. | Methods are disclosed for treating fibrous webs with water jet streams. A water impermeable member is employed as a member for supporting the fibrous web in the water jet steam treatment. The jet treatment is carried out on a plurality of water impermeable rolls multistagedly and parallely arranged in order to provide effective draining treatment and effective entangling treatment of fibers after having been carried out on a water impermeable belt in order to transfer toward said rolls. The nonwoven fabrics obtained through the method do not substantially comprise openings and the fibers are intricately and firmly entangled in three dimensional direction. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a stage driving apparatus and, more particularly, to a stage driving apparatus for a microscope.
2. Related Background Art
For the purpose of performing trimming in photography through a microscope or making a polarizing observation and a differential interference observation, it is desirable that a stage of the microscope be rotatable and movable two-dimensionally. One example of a construction of such a known microscope is that the stage mounted with a sample be rotatable about an optical axis of an observation optical system and be slid along a guide in a crosswise direction (hereinafter referred to as an "X-directional guide") and a guide in a lengthwise direction (hereinafter referred to as a "Y-directional guide") within a plane perpendicular to the optical axis of the observation optical system. In the thus constructed microscope, e.g., a joy stick may be given as an input member for inputting an operation signal for sliding the stage.
The operation signal inputted to the joy stick is outputted to a drive device for driving the stage. That is, when an operation lever of the joy stick is skewed in the crosswise direction, the drive device is operated, and the stage slides crosswise along the X-directional guide. On the other hand, when the operation lever is skewed in the lengthwise direction, the stage slides lengthwise along the Y-directional guide. Further, for instance, when the operation lever is skewed rightward obliquely at 45°, the stage slides equal distances respectively along the X- and Y-directional guides and therefore slides in the rightward oblique 45° direction. Thus, skew directions of the operation lever of the joy stick are coincident with moving directions of the stage along the two orthogonal guides.
There arise, however, the following problems inherent in the conventional microscope. For example, when the stage rotates through θ° from a fiducial initial rotating position (hereinafter termed a fiducial rotating position), the X- and Y-directional guides also rotate through θ° concomitantly with the stage. In this state, when the operation lever of the joy stick is skewed, e.g., in the crosswise direction, it follows that the stage moves not in the crosswise direction with respect to an observer but along the X-directional guide in a direction rotating through θ° from that direction. Further, in this state, when the operation lever is skewed in the lengthwise direction, the stage moves not in the lengthwise direction with respect to the observer but along the Y-directional guide in a direction rotating through θ° from that direction.
This is also the same as considering an observation image observed through an eyepiece of the microscope. That is, even when the joy stick is skewed crosswise to move the sample in the crosswise direction while the observer observes the sample, the observation image moves not in the crosswise direction but in the direction inclined at θ° from that direction.
Thus, in the state where the stage rotates through θ°, there is caused a relative deviation between the skew direction of the operation lever of the joy stick and the moving direction of the observation image observed through the eyepiece. Accordingly, the observer needs to operate the joy stick in consideration of the above relative deviation between the skew direction of the operation lever and the moving direction of the observation image. For instance, when the sample for observation is to be moved crosswise, the operation lever of the joy stick has to be operated in a direction inclined at -θ° from the crosswise direction. Further, when the sample is to be moved in the lengthwise direction, the operation lever has to be operated in a direction inclined at -θ° from the lengthwise direction.
Thus, in the conventional microscope, if the rotating position of the stage deviates from the fiducial rotating position, there is caused the relative deviation between the skew direction of the operation lever of the joy stick and the moving direction (moving direction of the observation image with respect to the observer) of the stage with respect to the microscope body. Consequently, the operation of the stage becomes troublesome and requires considerable skill. It is also difficult for the observer to quickly move the sample to the desired position.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the present invention to provide an apparatus capable of observing a sample on a stage by quickly moving it to a desired position with a simple operation to move the stage.
A stage driving apparatus according to the present invention comprises a stage mounted with a sample and rotatable about an optical axis of an observation optical system for observing the sample and two guides, for moving said stage within a plane perpendicular to the optical axis of the observation optical system, rotatable together with the stage and orthogonal to each other. The apparatus further comprises an input device for inputting a signal representing a moving direction of the stage, a converter for converting a signal inputted to the input device on the basis of an observation image of the sample on the stage through the observation optical system into an output signal with a compensated relative rotational deviation between a moving direction defined by the observation image and a moving direction defined by the two guides and a driving device for moving the stage along the two guides on the basis of the output signal from the converter.
According to the apparatus of the present invention, when the converter converts the stage operation signal inputted to the input member, it is possible to compensate a relative angular deviation between the observation image and the guide for moving the stage that is caused due to a rotation of the stage. According to the present invention, the stage moving command direction inputted to the input member is coincident with the moving direction of the observation image observed through an eyepiece, and, therefore, the stage moving command can be outputted without considering an angle of rotation of the stage. Accordingly, the moving operation for the stage in the microscope is simplified, and the quick observation can be also conducted.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become apparent during the following discussion in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view illustrating a microscope;
FIG. 2 is a diagram showing a relationship between X F - and Y F -axes and X s - and Y s -axes in a state where an angle of rotation of a stage is 0°;
FIG. 3 is an exploded view of the stage;
FIG. 4 is a sectional view taken along the arrowed line IV--IV of FIG. 3;
FIG. 5 is a perspective view illustrating a joy stick;
FIG. 6 is a perspective view illustrating a jog shuttle;
FIG. 7 is a perspective view illustrating a microscope in which the stage is rotated through θ°;
FIG. 8 is a diagram showing a relationship between the X F - and Y F -axes and the X s - and Y s -axes in the state where the angle of rotation of the stage is θ°;
FIG. 9 is a block diagram schematically illustrating a construction of the microscope in a first embodiment of the present invention;
FIG. 10 is a perspective view of a joy stick in a state where an operation lever is skewed at β° from a neutral position in a α° direction from an "X+" direction;
FIG. 11 is a diagram showing a relationship of a target point versus the X F - and Y F -axes and the X s - and Y s -axes in the state where the angle of rotation of the stage is θ°;
FIG. 12 is an exploded view of the stage of the microscope in a second embodiment of the present invention;
FIG. 13 is a sectional view taken along the arrowed line XIII--XIII of FIG. 12;
FIG. 14 is a perspective view illustrating the joy stick in the second embodiment;
FIG. 15 is a perspective view illustrating a jog shuttle in the second embodiment; and
FIG. 16 is a block diagram schematically showing a construction of the microscope in the second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a perspective view illustrating a microscope in a first embodiment of the present invention. Eyepieces 5 attached to a lens barrel 3 are disposed upwardly of an arm 2 supported on a base 1. A substage 6 is provided in front of and at the center of the arm 2. A stage 7 is rotatably mounted on an upper surface of this substage 6. FIG. 1 shows a case where a rotational position of the stage is an initial rotational position (fiducial rotational position), i.e., an angle of rotation is 0°. Now, herein, there are set an X F -axis indicating the horizontal direction and a Y F -axis indicating the vertical direction with respect to an observation image observed through the eyepieces 5. Set further are an X s -axis indicating the horizontal direction and a Y s -axis indicating the vertical direction with respect to the stage 7. When the angle of rotation is 0°, as illustrated in FIG. 2, the X F - and Y F -axes are coincident with the X s - and Y s -axes, respectively.
FIG. 3 is an exploded view of the stage 7. FIG. 4 is a sectional view taken along the arrowed line IV--IV. The stage 7 is equipped with guide members 10, 11 and 12. The guide member 11 is supported through races 13, 13 on both ends of the guide member 10. The guide member 11 is supported by those races 13 and are thereby slidable along the Y s -axis defined as an axis indicating the vertical direction on the stage 7 as explained above. Then, the guide member 11 is so constructed as to slide in the Y s -axis direction by operating a driving device (not shown) constructed of, e.g., ball screws and a linear motor, etc. On the other hand, the guide member 12 is supported by races 14 formed on an upper surface of the guide member 11 and is thereby slidable in the direction of the X s -axis defined as an axis indicating the horizontal direction on the stage 7 as explained above. Then, the guide member 12 is so constructed as to slide in the X s -axis direction by operating a driving device (not shown) constructed of, e.g., ball screws and a linear motor, etc. The guide member 12 is mounted with a couple of chuck arms 16 for seizing a slide glass 15 for holding a sample.
Fixed onto an upper surface of the substage 6 is an inner drum 20 with an optical axis Z of an observation optical system of this microscope being the center thereof. An outer drum 21 is so attached to the periphery of this inner drum 20 as to be rotatable about the optical axis Z. A gear 22 is formed along the periphery of this outer drum 21, and a small gear 23 meshing with this gear 22 is secured to a drive shaft of a motor 24 fixed to the substage 6. The construction of this embodiment is that an operating quantity of this motor 24 is detected by an absolute encoder 25. As illustrated in FIG. 4, the guide member 10 of the above stage 7 is mounted to this outer drum 21.
Next, an inputting member for inputting an operation signal for the stage 7 will be discussed.
At first, FIG. 5 is a perspective view of a joy stick 30 serving as an inputting member. The joy stick 30 includes an operation lever 31 for inputting an operation signal for sliding the stage 7 and an operation dial 32 for inputting an operation signal for rotating the stage 7. The Figure shows a state where the operation lever 31 shown by the solid line is in a neutral position. The operation lever 31 can be manipulated with a skew in an arbitrary direction from the neutral position indicated by this solid line by pushing it with a finger. The operation lever 31 is, when the finger gets separated therefrom, returns to the neutral position. Then, a direction in which the stage 7 slides is determined by the skew direction of the operation lever 31, while a speed at which the stage 7 slides is determined by a skew angle of the operation lever 31. For example, as explained above in FIG. 2, when the angle of rotation of the stage 7 is 0°, and if the X F - and Y F -axes are coincident with the X s - and Y s -axes, the operation lever 31 of the joy stick 30 shown in FIG. 5 is skewed in a α° direction from an "X+" direction as indicated by a one-dotted line 31' in the Figure. As a result, the guide member 11 slides in the Y F -axis (Y s -axis) direction with respect to the guide member 10, while the guide member 12 slides in the X F -axis (X s -axis) direction with respect to the guide member 11. With this operation, the sample held in the slide glass 15 moves in the α° direction from the X F -axis (X s -axis). Further, if an angle β at which the operation lever 31 is inclined from the neutral position is relatively large, the sample moves fast. Whereas if the angle β is relatively small, the sample moves slow. Note that the above-described stage 7 is slid by operating the driving device as explained earlier.
On the other hand, the operation dial 32 can be rotatably operated, and a quantity of rotation of the stage 7 is determined based on a quantity of rotation of the operation dial 32. For example, when the operation dial 32 is rotated from the fiducial position thereof, the motor 24 explained before with reference to FIGS. 3 and 4 is operated. Then, the stage constructed of the guide members 10, 11 and 12 is integrally rotated through θ° from the fiducial rotational position. It is to be noted that the rotational quantity of the stage 7 is detected by the absolute encoder 25 through an operation quantity of the motor 24 in this embodiment.
Further, FIG. 6 is a perspective view illustrating a jog shuttle 40 by way of another example of the inputting member. The jog shuttle 40 has operation buttons 41-44 for inputting an operation signal for sliding the stage 7 and an operation dial 45 for inputting an operation signal for rotating the stage 7. As illustrated in FIG. 2, the guide member 12, when pushing the operation button 41 in a state where the angle of rotation of the stage 7 is 0°, slides in a (+) direction (right direction in FIG. 2) of the X F -axis (X s -axis) with respect to the guide member 11 but slides, when pushing the operation button 43, a (-) direction (left direction in FIG. 2) of the X F -axis (X s -axis) with respect to the guide 11. Similarly, the guide member 11, when pushing the operation button 42 (or 44), slides in the (+) (or (-)) direction (up or down direction in FIG. 2) of the Y F -axis (Y s -axis) with respect to the guide member 10. Thus, the jog shuttle 40 is capable of moving the sample held in the slide glass 15 to a desired position by properly operating the operation buttons 41-44. On the other hand, the operation dial 45 is constructed absolutely in the same way as the operation dial 32 of the joy stick 30 explained above, and therefore its explanation will be omitted.
FIG. 7 is a perspective view of the microscope in a state where the stage 7 is thus rotated through θ°. At this time, the preset relationship between the X F - and Y F -axes and the X s - and Y s -axes goes as in a state where the, X s -axis rotates through θ° from the X F -axis, while the Y s -axis rotates through θ° from the Y F -axis as shown in FIG. 8.
FIG. 9 is a block diagram schematically illustrating a construction of the microscope in this embodiment. Operation signals from the joy stick 30 and the jog shuttle 40 serving as the input members are inputted to a control circuit 50 and, after being converted in the control circuit 50 as will be explained in greater detail, outputted to a driving device 51 of the stage 7. Further, in this embodiment, the rotational quantity of the stage 7, which has been detected by the absolute encoder 25, is inputted to the control circuit 50. The following explains how the signal in the control circuit 50 is converted for compensating a relative angular deviation between the X F - and Y F -axes on the basis of the observation image of the sample and the X s - and Y s -axes on the basis of the stage 7, i.e., for compensating the angle-of-rotation θ previously explained in FIG. 8.
To start with, there will be explained a case where the operation lever 31 of the joy stick 30 is, in the rotated-through-θ°-state of the stage 7 as shown in FIGS. 7 and 8, skewed at β° from the neutral position in the α° direction from the "X+" direction as illustrated in FIG. 10. If no signal conversion is performed, it follows that the sample would be moved in a further-deviated-by-α° direction from the X s -axis deviated by θ° from the X F -axis. That is, it follows that the sample would be moved in a (θ+α°) direction.
Thus, the invention provides a conversion is to be executed in the control circuit 50 to eliminate an influence by a deviation angle θ between relative angles made by the X F - and Y F -axes and by the X s - and Y s -axes. Outputted to the slide member of the stage 7 are output signals calculated by the following formulae (1) and (2):
X.sub.s -Directional Speed Component=Lcos (α-θ)(1)
Y.sub.s -Directional Speed Component=Lsin (α-θ)(2)
where L is the speed coefficient (mm/s) corresponding to a skew angle β of the operation lever 31. If the skew angle β becomes larger, the speed coefficient L also increases. Whereas if the skew angle becomes smaller, the speed coefficient L decreases. Further, a ratio R of the X s -directional speed component to the Y s -directional speed component is calculated by the following formula (3): ##EQU1##
The control circuit 50 sets the ratio of the X s -directional speed component to the Y s -directional speed component at 1:R and thus controls the stage, whereby an object on an observation center O shown in FIG. 11 can be made to linearly reach a target point A.
For example, when L=10 mm/s, θ=15° and α=0°, from the formulae (1) and (2), the following are established:
X.sub.s -Directional Speed Component=10×0.97=9.7 mm/s
Y.sub.s -Directional Speed Component=10×(-0.26)=-2.6 mm/s
Then, it follows that the sample on the stage moves at a speed of 9.7 mm/s with respect to the X s -axis and at a speed of -2.6 mm/s with respect to the Y s -axis. Further, from the above formula (3), the speed component ratio R at this time is given by:
R=-2.6/9.7=-0.27
Also, for example, when L=10 mm/s, θ=15° and α=45°, from the formulae (1) and (2), the following are established:
X.sub.s -Directional Speed Component=10×0.86=8.6 mm/s
Y.sub.s -Directional Speed Component=10×(0.5)=5.0 mm/s
From the formula (3), the ratio R of the X s -directional speed component to the Y s -directional speed component is given by:
R=5.0/8.6=0.58
Thus, according to this embodiment, the operation signal for the stage 7, which has been inputted in the joy stick 30, is converted in the control circuit 50, thereby making it possible to compensate the deviation between the relative angles made by the X F - and Y F -axes on the basis of the observation image and by the X s - and Y s -axes on the basis of the stage 7. Accordingly, it follows that the skew direction of the operation lever 31 of the joy stick 30 coincides with the direction in which the sample moves within the observation visual field. The observer is thereby capable of performing the moving operation for the stage 7 without considering the angle-of-rotation θ of the stage 7.
Given next is an explanation of a case of using the jog shuttle 40. When employing the jag shuttle 40, the control circuit executes the following conversions to compensate the angular deviation due to the rotation of the stage 7.
* When the operation button 41 is pushed:
X s -Directional Speed Component=Mcos (θ)
Y s -Directional Speed Component=Msin (-θ)
* When the operation button 42 is pushed:
X s -Directional Speed Component=Msin (θ)
Y s -Directional Speed Component=Mcos (θ)
* When the operation button 43 is pushed:
X s -Directional Speed Component=-Mcos (θ)
Y s -Directional Speed Component=Msin (θ)
* When the operation button 44 is pushed:
X s -Directional Speed Component=Msin (-θ)
Y s -Directional Speed Component=-Mcos (θ)
where M is the speed coefficient (mm/s) and takes a predetermined value.
When such conversions are used, it is possible to compensate the deviation between the relative angles made by the X F - and Y F -axes on the basis of the observation image and by the X s - and Y s -axes on the basis of the stage 7, which is caused due to the rotation of the stage 7. The observer is capable of outputting a command to move the stage 7 with the aid of the jog shuttle 40 without considering the angle-of-rotation θ of the stage 7.
Note that the embodiment discussed above has the construction for detecting the rotational quantity of the stage 7 by use of the absolute encoder 25 through the operation quantity of the motor 24. That construction is not, however, required. For instance, the construction may be such that the operation quantity of the operation dial 32 of the joy stick 30 is detected by the encoder, etc. and then outputted to the control circuit, and the control circuit obtains the rotational quantity of the stage 7 on the basis of the operation quantity thereof. With this construction also, the same effect as that in the embodiment discussed above can be obtained.
The driving apparatus according to the present invention can be implemented in a microscope having a manually rotated stage. FIGS. 12 and 13 illustrate a second embodiment of the present invention. FIG. 12 is an exploded view of a stage 60 that is manually rotated. FIG. 13 is a sectional view taken along the arrowed line XIII--XIII of FIG. 12. This stage 60 has substantially the same construction as the stage 7 already explained in FIGS. 3 and 4, except that the stage 60 is manually rotated. Hence, the same members as those in FIGS. 3 and 4 are marked with the like symbols, and the explanation thereof will be omitted.
A gear 61 is formed along the periphery of an outer drum 21 so attached to the periphery of the inner drum 20 as to be rotatable about the optical axis Z on the upper surface of the substage 6. A small gear 62 meshing with this gear 61 is secured to an input shaft 64 of a potentiometer 63 fixed to the substage 6. A handle 65 is fitted to an input shaft lower end 64 of this potentiometer 63. The stage 60 can be rotated by manually rotating this handle 65. Further, a knob 66 is attached to a lower surface of the guide member 10 constituting the stage 60. The stage 60 can be also manually rotated by rotating this knob 66. Then, an angle of rotation of the stage 60 rotated by the handle 65 or the knob 66 is detected by the potentiometer 63.
An input member for inputting an operation signal for this stage 60 may be constructed of, e.g., a joy stick 70 as shown in FIG. 14 or a jog shuttle 80 as illustrated in FIG. 15. The joy stick 70 includes an operation lever 71 for inputting an operation signal for sliding the stage 60 but does not include an operation dial for inputting an operation signal for rotating the stage 60. Note that the joy stick 70 has substantially the same construction as the joy stick 30 explained earlier in FIG. 5 except for such a point that the operation dial is not provided, and, therefore, the explanation thereof will be omitted. The jog shuttle 80 has operation buttons 81-84 for inputting an operation signal for sliding the stage 60 but does not include the operation dial for inputting the operation signal for rotating the stage 60. Note that the jog shuttle 80 has substantially the same construction as the jag shuttle 40 explained earlier in FIG. 6 except for such a point that the operation dial is not provided, and, therefore, the explanation thereof will be omitted.
FIG. 16 is a block diagram schematically illustrating the construction of this embodiment. The operation signals from the joy stick 70 or the jog shuttle 80 are inputted to a control circuit 90. The control circuit 90 performs absolutely the same arithmetic processes as those in the control circuit 50 previously explained and outputs a signal to a driving device for the stage 60. Further, a rotational quantity of the stage 60 that has been detected by a potentiometer 63 is inputted to the control circuit 90. The control circuit 90, as in the same way with the first embodiment discussed above, converts the operation signals from the joy stick 70 and the jog shuttle 80 to compensate the deviation between the relative angles made by the X F - and Y F -axes on the basis of the observation image of the sample observed through the eyepieces 5 of the microscope and by the X s - and Y s -axes on the basis of the stage 60.
In accordance with this embodiment also, the same effect as the first embodiment discussed above can be obtained.
It is apparent that, in this invention, a wide range of different working modes can be formed based on the invention without deviating from the spirit and scope of the invention. This invention is not restricted by its specific working modes except being limited by the appended claims. | A stage driving apparatus comprises a stage mounted with a sample and rotatable about an optical axis of an observation optical system for observing the sample, and two guides, for moving the stage within a plane perpendicular to the optical axis of the observation optical system, rotatable together with the stage and oriented orthogonal to each other. The apparatus further comprises an input device for inputting a signal representing a moving direction of the stage, a converter for converting a signal inputted to the input device on the basis of an observation image of the sample on the stage through the observation optical system into an output signal with a compensated relative rotational deviation between a moving direction defined by the observation image and a moving direction defined by the two guides and a driving device for moving the stage along the two guides on the basis of the output signal from the converter. | 6 |
FIELD OF THE INVENTION
The present invention relates to storage containers in general, and in particular, to storage containers for flat, objects, wherein the storage containers also have apparatus for displaying a selected object without having to remove that object from the container.
BACKGROUND OF THE INVENTION
Flat objects such as floppy diskettes, phonographic records and `compact discs` are often kept in generally rigid, closable storage containers. These storage containers prevent mechanical damage to the stored objects, reduce the exposure of the objects to dust, and, in general, provide a convenient means of storing and transporting floppy diskettes and compact discs. The objects are stored parallel to each other, inclined at a small angle to the base of the container. Due to the relatively large number of objects that may be stored in a single container, e.g. about 20 or 30, searching for a particular diskette or compact disc may be tedious and time-consuming.
Described in U.S. Pat. No. 4,609,231 is a container for storing planar objects. The container enables a selected object to be rapidly located by lifting successive stored planar objects so as to display a portion thereof. To achieve this there is provided a rotatable camshaft extending along the length of the container, and a plurality of cams corresponding to a plurality of support arms for stored planar objects. The cams are spaced along the camshaft and are also spaced radially thereabout so that axial rotation of the camshaft causes successive lifting engagement of a single support arm by its corresponding cam so as to lift and expose a portion of the object on each support arm.
It would be advantageous to provide a means of displaying an entire surface portion of a stored object so as to more readily permit identification thereof. It would also be advantageous to provide a means of successively displaying stored flat objects by less complex means than those described in the above-referenced U.S. Patent.
U.S. Pat. No. 3,812,975 describes phonograph record holding apparatus including a plurality of pivotal record holding members which are constructed and arranged such that the forward tilt of an end one of the members is operative to cause the automatic forward pivoting of the remainder of the members. U.S. Pat. No. Re. 27,462 describes a photograph record rack having a frame and a plurality of spaced parallel axially pivoted record holding members. The holding members are constructed and arranged such that the tilting of one member is operative to cause the automatic pivoting of an adjacent holding member.
Disadvantages inherent in both of the above-described U.S. patents is that they provide no means for controlling the automatic successive tilting of adjacent, hitherto non-tilted holding members, and that the construction of both devices is inherently complex and may result in jamming thereof.
The following patents are also noted as describing storage apparatus for flat objects and including features of either static display of stored objects or individual manual pivoting of compartments for storing a plurality of flat objects or of single object compartments: U.S. Pat. Nos. 3,100,671; 3,556,620; 4,239,307; and 4,684,019.
SUMMARY OF THE INVENTION
The present invention seeks to provide a storage container for flat objects, wherein the container also has apparatus for successively displaying an entire surface portion of each stored object so as to enable rapid visual scanning thereof, thereby overcoming disadvantages of known art.
There is provided, therefore, in accordance with an embodiment of the invention, storage apparatus for flat objects including a container configured to hold a plurality of flat objects; and apparatus associated with the container for selectably rotating successive ones of the objects between first and second positions so as to display a selected surface of each successively rotated object.
Additionally in accordance with an embodiment of the invention, the apparatus for selectably rotating includes a plurality of spaced apart support elements mounted for rotation about a plurality of respective, parallel pivot axes, each the support element being configured to support a single flat object in either of the first or second positions; and apparatus for selectably engaging successive support elements so as to cause pivoting thereof about the pivot axes so as to rotate successive ones of the flat objects between the first and second positions.
Further in accordance with an embodiment of the invention, the container includes a base and the plurality of pivot axes are oriented generally parallel to the base, each support element defining a support portion extending generally away from the base and further defining a protrusion extending from the pivot axis towards the base, the apparatus for selectably engaging being operable to successively engage each protrusion so as to cause pivoting of each support element.
Additionally in accordance with an embodiment of the invention, the apparatus for selectably engaging includes an engagement element mounted for translation along an axis transverse to the pivot axes as to successively engage and cause pivoting of each support element; and apparatus for selectably displacing the engagement element along the transverse axis.
Further in accordance with an embodiment of the invention, the engagement element includes a movable cam member having an internally threaded bore and which is configured to engage each protrusion, and the apparatus for selectably displacing includes a drive screw mounted along the transverse axis and extending through the threaded bore so as to engage the cam; apparatus for rotating the drive screw; and apparatus for preventing rotation of the cam member about the drive screw so as to cause linear translation of the cam along the drive screw and thereby cause successive engagement of the protrusions of the support elements by the cam.
According to an alternative embodiment of the invention, the apparatus for selectably engaging includes an elongate rotatable member having first and second ends and mounted along an axis transverse to the pivot axes; and a helical screw member mounted onto the rotatable member so as to be rotatable therewith and configured to engage successive protrusions when the rotatable member is rotated.
According to yet a further embodiment of the invention, the movable member includes an elongate cam member mounted for movement along its longitudinal axis and defining a plurality of cam portions equal to the number of support elements and arranged along the cam member so as to successively engage and rotate predetermined support elements.
In accordance with an additional embodiment of the invention, protrusion of each support element is made of a magnetic material and the engagement element is a magnet.
In accordance with a further embodiment of the invention, the apparatus for successively rotating each of the objects between first and second positions includes apparatus for successively engaging the objects so as to cause successive rotation thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more fully understood and appreciated from the following detailed description, taken in conjunction with the drawings, in which:
FIGS. 1A and 1B are respective cut-away perspective and side views of storage and display apparatus for flat objects, employing a single cam mounted onto a drive screw and constructed in accordance with an embodiment of the invention;
FIG. 2 is an enlarged perspective illustration of a single support element used in the storage and display apparatus of FIGS. 1A and 1B;
FIGS. 3A-3C illustrate the rotation and display of a single object stored in the storage and display apparatus of FIGS. 1A and 1B;
FIGS. 4A and 4B are respective cut-away perspective and side views of storage and display apparatus for flat objects, similar to the apparatus of FIGS. 1A and 1B but employing support elements configured so as to permit closer spacing than that permitted by the support elements employed in the apparatus of FIGS. 1A and 1B;
FIG. 5 is an enlarged perspective illustration of a single support element used in the storage and display apparatus of FIGS. 4A and 4B;
FIG. 6 is a cut-away side view of storage and display apparatus employing a single cam member mounted onto a pulley system;
FIG. 7 is a cut-away side view of storage and display apparatus employing a 360° turn helical cam member;
FIG. 8 is an enlarged view taken along line VIII--VIII in FIG. 7;
FIG. 9 is a cut-away side view of storage and display apparatus employing a cam member defining a plurality of cam portions;
FIG. 10 is a cut-away side view of storage and display apparatus generally similar to that illustrated in FIGS. 1A, 1B, 4A and 4B, but employing support elements constructed according to yet a further alternative embodiment of the invention;
FIG. 11 is a cut-away side view of storage and display apparatus employing magnetic rotation apparatus;
FIG. 12 is a cut-away side view of storage and display apparatus employing gas jet rotation apparatus;
FIG. 13 is a cut-away side view of storage and display apparatus employing gas jet rotation apparatus constructed according to an alternative embodiment of the invention; and
FIGS. 14A-14D are diagrammatic illustrations of the reversal in direction of the gas jet apparatus of FIG. 13.
DETAILED DESCRIPTION OF THE INVENTION
Reference is made to FIGS. 1A and 1B, which illustrate storage and display apparatus for flat objects, such as floppy diskettes and compact discs. The apparatus, referenced generally 10, includes a boxlike container 12 for storing a plurality of the flat objects, indicated at 14. Mounted within the container 12 is apparatus 16 (FIG. 1B) for successively rotating each of the objects 14 between first and second relatively inclined positions, shown generally at 13 and 15 respectively, so as to display a selected surface 18 of each object. The rotation of each stored object 14 causes virtually the entire surface 18 of each object to be displayed. As this virtually maximizes the amount of visual information available to a person searching for a particular object it greatly eases the search for a specific object 14 stored among a plurality of the objects.
Referring now also to FIG. 2, apparatus 16 includes a plurality of spaced apart support elements 20 mounted by a plurality of parallel pivot members 22 into a mounting member 19 (FIGS. 1A and 1B). Each support element 20 is configured to support a single object 14 in either of the first or second positions as may be defined by transverse stop members 21 forming part of, or mounted onto mounting member 19. Each support element 20 may be rotated about a pivot axis 23, defined by pivot member 22, by engagement with a cam member 24 (FIG. 1B).
In the shown embodiment, each support element defines a first portion 26 extending away from base 28 of the container 12 and a second portion 30 extending towards base 28. In the present example, the second portion 30 of each support element 20 defines first and second leg-like protrusions, referenced 33 and 35 respectively. The cam member 24 is mounted, via a threaded bore 31 (FIG. 1B), onto a drive screw 32 rotatable about a fixed axis 34 extending through a lower portion of the container and oriented transversely to the pivot members 22. Rotation of a knob or handle 36 (FIG. 1B) mounted externally of the container, causes rotation of drive screw 32 via first and second gear wheels 38 and 40. As cam member 24 has a bottom surface 42 which engages bottom surface 44 of the container, the rotational motion of the drive screw 32 causes a linear translation of cam member 24 along axis 34.
As shown in FIG. 1B, cam member 24 defines a single cam portion 46 which is operative to engage either of respective first or second protrusions 33 and 35 of downwardly extending portion 30 of an adjacent support element.
Referring now to FIGS. 3A-3C, the operation of the apparatus of FIGS. 1A and 1B is described. As cam member 24 is moved in the direction indicated by arrow 48, cam portion 46 is brought into engagement with second protrusion 35 so as to cause the entire associated support element 20 to rotate about pivot axis 23. The object 14 hitherto supported by support element 20 in a first portion is, therefore, also rotated and comes to rest on an adjacent support element in a first portion 13.
According to a preferred embodiment of the invention, cam portion 46 has a pair of sloped surfaces 50 (FIG. 1B) which terminate in a rounded peak 52. It will be appreciated that this reduces the possibility of the cam member 24 becoming jammed with a portion of a support element 20 in an intermediate position. Alternatively, or in addition, either one of protrusions 33 and 35 may be weighted, so as to impart an inherent instability to the support element.
Referring once again to FIGS. 1B and 2, as the first and second protrusions 33 and 35 lie along coplanar axes 33" and 35" (FIG. 2), in order to permit adequate clearance between facing first and second protrusions 33 and 35 of adjacent support elements 20, the spacing S 1 (FIG. 1B) between adjacent pivot axes 23 must slightly greater than the combined width W 1 of first and second protrusions 33 and 35.
Reference is now made briefly to FIGS. 4A and 4B, which illustrate apparatus 10 of the invention, but wherein the support elements 54 employed are as shown in FIG. 5. According to the present embodiment, respective first and second protrusions 56 and 58 of support elements 54 are staggered along the pivot axis 23, such that protrusions 56 and 58 lie along non-coplanar axes 56" and 58" (FIG. 5). In order to permit adequate clearance between facing first and second protrusions 56 and 58 of adjacent support elements 54, the spacing S 2 (FIG. 4B) between adjacent pivot axes 23 is required to be slightly greater than the width W 2 of only a single one of first and second protrusions 33 and 35 plus the thickness of pivot member 22. It will be appreciated, therefore, that a larger number of support elements may be mounted, and consequently, a larger number of objects may be stored, in a container 12 constructed according to the present embodiment, than according to the embodiment of FIGS. 1A-2.
In addition, whereas the maximum length of first and second protrusions 33 and 35 (FIGS. 1B and 2) is equal to half of the spacing between adjacent pivot members 22, the described staggering of the protrusions 56 and 58 (FIGS. 4B and 5) permits their length to be equal to the entire spacing between adjacent pivot members, such that for spacing S 2 =S 1 , the protrusions 56 and 58 may be approximately twice the length of protrusions 33 and 35 and constitute, therefore, lever arms twice the length of their non-staggered counterparts. Accordingly, the rotation apparatus 16 constructed according to the present embodiment, employing staggered protrusions, allows for less accurate dimensions than are required with the embodiment of FIGS. 1A-2.
FIG. 6 illustrates storage and display apparatus similar to that shown and described above in conjunction with FIGS. 1A, 1B, 4A and 4B, but employing a cam member 60 that is movable along axis 62 via a drive belt 68 to which it is attached and which forms part of a pulley system 64. A desired direction of movement of cam member 60 is achieved by rotation of handle 36 mounted externally of the container, which causes rotation of pulley wheel 66 via first and second cooperating helical gears 39 and 41, so as to drive the belt 68. Pulley wheel 66 is mounted coaxially with helical gear 41 about an axis 70 which is perpendicular to axis 62.
Reference is now made to FIG. 7, which illustrates storage and display apparatus similar to that shown and described above in conjunction with FIGS. 1A and 1B, but, in place of the drive screw 32 and the cam member 24, the present embodiment employs an elongate, axially rotatable rod member 72, having a helical cam element 74. Helical cam element 74 undergoes a rotation of 360° along the length of the container 12.
Accordingly, as the rod member 72 is axially rotated, respective predetermined portions of the helical cam member 74 are rotated upwards, (as seen in the orientation of the apparatus illustrated in FIG. 7) so as to engage a predetermined protrusion of each corresponding support element 20. This is shown particularly clearly in FIG. 8, in which a hatched portion 74" of the helical cam member 74 is shown to be engaging a first protrusion 33 of support element 20. As rod member 72 is rotated in the direction indicated by arrow 78, portion 74" undergoes a motion having, inter alia, an upward component, indicated by arrow 80, so as to engage an edge portion 76 of first protrusion 33 of the support element 20.
As rod member 72 is rotated further, the first protrusion 33 of the support element 20 is rotated as indicated by arrow 82 (also shown in FIG. 7). Accordingly, the entire support element 20 is rotated about its pivot axis 23.
Reference is now made to FIG. 9, which illustrates storage and display apparatus having a container 12 and support elements 20 as shown and described above in conjunction with FIGS. 1A and 1B, but wherein there is provided a cam member 78 mounted for movement along its longitudinal axis 80 and having a plurality of differently spaced cam portions 82a, 82b, 82c, 82d, . . .
According to the illustrated embodiment, the plurality of support elements 20 are distributed at a pitch `p` as measured parallel to axis 80, and the cam portions 82a-82d are spaced at uniformly increasing intervals so that first protrusions 33 of adjacent support elements 20a, 20b, 20c and 20d are successively engaged by their corresponding cam portions 82a-82d. For purposes of clarity, the pivot members 22 are indicated on the drawing as 22a, 22b, 22c and 22d, and are illustrated as defining respective pivot axes 23a, 23b, 23c and 23d.
According to the present embodiment, when the first cam portion 82a is in alignment with pivot axis 23a, along axis 80, cam portion 82a is spaced from its corresponding pivot member axis 22b by a distance d; cam portion 82c is spaced from its corresponding pivot member axis 22c by a distance 2d; and cam portion 82d is spaced from its corresponding pivot axis 22d by a distance 3d, where d=P/N, N being the total number of support elements.
It will thus be appreciated that when there are N support elements 20 arranged at a pitch P, the spacing between the nth cam portion and the (n-1)th cam portion equals:
P-[d×(N-1)].
Quality d is typically very small, and in order to permit satisfactory operation of the present embodiment of the invention, there is provided, in the present example, a knob or handle 86 having a radius that is relatively large when compared to d. Knob 86 is operative to rotate 360° turn helical cam 88 about an axis 90. The helical cam is operative to engage an end groove defined 91 defined by elongate cam member 78 so as to move it in a selected axial direction and so as to provide successive rotation of support elements 20. As shown, the end 92 of cam member 78 is spaced from an adjacent wall portion 93 of container 12 by a distance equal to at least P.
Reference is now made briefly to FIG. 10, in which there is illustrated an embodiment of the invention similar to that of FIGS. 1A and 1B, but employing support elements 94, which have a different configuration to that of support elements 20 of the embodiment of FIGS. 1A and 1B. According to the present embodiment, each support element 94 has a planar protrusion 96 extending towards base 28 of the container and a larger planar portion 98 extending away from base 28. Typically, protrusion 96 and portion 98 are coplanar.
A further difference between the present embodiment and that of FIGS. 1A and 1B, is that in the present embodiment, a cam member 97 is employed in place of cam member 24 (FIG. 1B). As illustrated, cam member 97 includes an upper cam portion 99 of a flexible construction. Portion 99 may, for example, be a leaf spring. This flexibility is required so as to permit passage of the cam member past protrusion 96 of a support element 94 which are required to be overlapping at all times so as to enable mutual engagement when the cam member is travelling in either direction along axis 34. Alternatively, protrusions 96 may have a flexible construction while the cam member has a construction similar to that of cam member 24 (FIG. 1B).
Referring now to FIG. 11, there is shown a storage and display system similar to that illustrated in FIG. 10, but wherein a magnetic displacement member 100 is provided, and protrusions 96 of support elements 94 are made of a magnetic material, typically a ferromagnetic material. As magnetic member 100 is displaced along axis 34, it exerts a magnetic force on a corresponding support element 94, via its magnetic protrusion 96, so as to cause rotation of the support element about its pivot axis 23, thereby causing a similar rotation of an object 14 supported thereby. A particular advantage of the illustrated embodiment is that as it employs a non-contact method of rotationally engaging the support elements, there is a reduced risk of jamming occurring between a support element and the displacement (cam) member.
Referring generally now to FIG. 12, there is illustrated storage and display apparatus 110 for flat objects, constructed in accordance with yet further embodiments of the invention. Apparatus 110 employs a container 112, in association with which is mounted gas jet apparatus 114 for successively rotating each of the objects 14 between first and second relatively inclined positions, shown generally at 113 and 115 respectively, so as to display a selected surface 18 of each object. As described above in conjunction with the embodiment of FIGS. 1A and 1B, the rotation of each stored object 14 causes virtually the entire surface 18 of each object to be displayed.
According to the illustrated embodiment apparatus 110 includes a plurality of spaced apart support elements 120 mounted onto a plurality of parallel pivot members 122 defining pivot axes 123 and mounted onto a mounting member 125. Each support element 120 is configured to support a single object 14 in either of the first or second positions, and may be rotated about its pivot axis 123 by the rotation of an object 14 supported to the rear of the support element 120. Rotation of the supported object is achieved by application thereto of a high pressure jet of gas provided by gas jet apparatus 114.
In the illustrated embodiment, the gas jet apparatus includes a nozzle 124, mounted for free rotation about an axis 126 extending through a carriage member 128. The carriage member 128 is mounted, via a threaded bore (not shown) onto a drive screw 132 rotatable about a fixed axis 134 extending through an upper portion of the container and oriented transversely to the pivot axes 123. Rotation of a knob or handle 136 mounted externally of the container, causes rotation of drive screw 132 via first and second gear wheels 138 and 140. Typically, carriage member 128 is prevented from rotation about axis 134 by means of a surface (not shown) arranged for sliding travel along a side portion 142 of the container. Accordingly, rotation of the drive screw 132 causes a linear translation of carriage member 128 along axis 134.
As carriage member 128 is moved, for example, in the direction indicated by arrow 143, gas nozzle 124 engages an edge of one of the stored objects, referenced 14', and is thus pivoted about axis 126. Once the gas nozzle is rotated to a predetermined angle, a high pressure jet 127 of gas is provided so as to exert a force on the object immediately in front, referenced 14", so as to cause its rotation from first inclined position 113 to second inclined position 115. As the object 14" is thus rotated, it rotatably engages the support element 120' immediately in front of it. Typically, although not necessarily, the gas used is filtered air provided from a source 121, which may be, for example, any suitable light duty compressor known in the art.
According to an alternative embodiment, however, support elements 120 are not provided, and each object 14 rests on an adjacent object and, when rotated, therefore, its rotation between the first and second positions is unobstructed.
FIG. 13 illustrates storage and display apparatus similar to that shown in FIG. 12, but wherein the gas jet apparatus, referenced generally 144, includes a gas jet nozzle 145 mounted onto a carriage 146 is configured to slide freely along drive screw 132. Carriage 146 is drawn along the drive screw 132 by an internally threaded, generally C-shaped leader 148. Leader 148 is typically mounted between the drive screw 132 and portion 142 of the container. Alternatively, portion 142 may be replaced by a track member (not shown) parallel to the drive screw and extending along the length of the container. Carriage 146 and leader 148 are connected via an articulated connection 150, so as to enable movement of the gas jet apparatus in either direction along the axis 134.
In contrast to the embodiment of FIG. 12, gas nozzle 145 is not brought into touching engagement with the stored objects 14, but is instead inclined, according to the direction of travel, in either of two predetermined positions 152 and 154 defined by stop members 156 and 158 formed on carriage 146. The gas nozzle 145 provides a gas of jet so as to rotationally displace an engaged object 14 as described above in conjunction with the embodiment of FIG. 12.
In the position illustrated, gas jet apparatus 144 is being displaced along axis 134 towards a first end 160 of drive screw 132. To reverse the direction of movement of the apparatus 144 such that it travels towards a second end 161 of the drive screw, the direction of rotation of drive screw 132 is reversed.
As illustrated in FIGS. 14A-14D, as the direction of movement of leader 148 is reversed, as indicated by arrow 162 (FIG. 14A), leader 148 moves towards carriage 146 while gas nozzle 145 is rotated clockwise (in the illustration) about axis 147 until leader 148 passes the carriage 146 and eventually takes up the position shown in FIG. 14D. At this position, further rotation of gas nozzle 145 is prevented by stop members 156 and 158 and so uniform movement of the entire gas jet apparatus 144 towards the second end 161 of drive screw 132 may commence.
As with the embodiment of FIG. 12, the present embodiment also, does not necessarily include support elements 120 and each object 14 rests on an adjacent object and, when rotated, therefore, its rotation between the first and second positions is unobstructed.
It will be appreciated by persons skilled in the art that the scope of the present invention is not limited to what has been specifically shown and described hereinabove by way of example. The scope of the present invention is limited, rather, solely by the claims, which follow. | A storage container for a plurality of flat objects is disclosed. The container has apparatus for successively displaying a surface portion of each stored object so as to enable rapid visual scanning. The apparatus rotates successive objects from a first display position to a second position which displays the next successive object. | 0 |
This application is a Continuation-In-Part Application, which claims priority from U.S. application Ser. No. 10/348,357, filed 21 Jan. 2003, issued on 30 Mar. 2004 as U.S. Pat. No. 6,712,040, entitled VARIABLE THROTTLE VALVE, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for regulating flow through a passage. More particularly, the present invention relates to a rotary valve.
2. Description of Related Art
Spark ignition internal combustion engines often employ a butterfly valve in a throttle valve assembly to control air intake. While a butterfly valve works adequately, the horsepower can be increased if the valve employed in the throttle assembly is less restrictive, since the butterfly valve shaft and the plate remain in the airflow path, obstructing airflow while in open throttle. In the past, slide throttles, pivoting variable intakes and other means have been used to reduce restriction in the intake path. An important consideration in the design of non-butterfly intake valves is airflow control, turbulence and low throttle response. Because of their long use and development, butterfly intake valves have been developed which adequately address those issues, but many non-butterfly systems still present problems in partial throttle situations. One non-butterfly intake control type utilizes barrel valves which rotate between a closed position and an open position. However, known barrel valve systems have numerous limitations and disadvantages compared to butterfly systems at partial throttle openings. The present invention solves these and other problems previously encountered with barrel valve intake systems.
SUMMARY OF THE INVENTION
The present invention is for variable area which employs at least two barrels which are parallel to one another and rotate in synchronization with one another. The barrels contain openings perpendicular to their rotational axes which mate at the interface of the barrels so that they can create an opening perpendicular to the barrels which is concentric with a port in a manifold or valve body. The openings in each barrel provide an opening of a desired size at an open position and a predetermined minimum size at a closed position. The closed position can also be a completely closed position to cut off flow entirely. Once benefit of the invention is that the openings in the barrel may be sized so that they can match non-circular manifold openings.
A further benefit of the present invention is that the openings can be sized and the gearing between barrels chosen, so that the intake area at intermediate settings is a nonlinear function of control setting applied to the barrel valves. In this way, tuning of the system can be varied to obtain a desired response.
In one aspect, the invention is a variable aperture valve comprising a first cylinder having a first aperture and a second cylinder having a second aperture. The first cylinder moves between a first position and a second position. The second cylinder moves in cooperation with the first cylinder such that the first aperture and the second aperture form a variable sized opening when the first cylinder moves from the first position towards the second position. The variable sized opening is in a relatively closed position when in the first position. The valve comprises a block body including a passage for allowing air to pass therethrough. The first cylinder and the second cylinder are coupled with the block body and configured in a predetermined position such that the variable sized opening is in communication with the passage. The valve also includes an axle for driving the first cylinder and the second cylinder.
In one presently preferred embodiment of the invention, a variable valve comprises a first cylinder having a first aperture, wherein the first cylinder moves between a first position and a second position. A second cylinder has a second aperture. The second cylinder moves between the first position and the second position such that the first aperture and the second aperture form a variable sized opening when the first cylinder and the second move from the first position toward the second position, the second cylinder moving in cooperation with the first cylinder. The valve further comprises a gear assembly having a first set of gears coupled to the first cylinder and the second of gears coupled to the second cylinder. The first set of gears sand the second set of gears are geared to one another. The variable sized opening is in a closed position when the first cylinder and the second cylinder are in the first position. The valve further comprises a block body which includes a passage for allowing air to pass through the block body. The first cylinder and the second cylinder are coupled to the block body and configured in a predetermined position. The variable sized opening is in communication with the passage. The valve further comprises an axle for driving the first cylinder and the second cylinder. The axle is coupled to the block body. The first cylinder and the second cylinder move in an opposite direction from one another or in a same direction with one another. In a currently preferred embodiment, the first cylinder and the second cylinder rotate on respective axes which are parallel to one another.
In another aspect of the invention, a variable valve apparatus comprises a body; a first rotatable cylinder and a second rotatable cylinder coupled to the body. The first rotatable cylinder is coupled to the body and has a first aperture cut therethrough. The second rotatable cylinder has a second aperture cut therethrough. The second rotatable cylinder is configured to rotate in an opposite direction from the first rotatable cylinder, whereby the first aperture and the second aperture form a variable sized opening. The first aperture and the second aperture do not form the opening when the first rotatable cylinder is in a closed position. The body further comprises a passage for allowing air to pass through the body. The first rotatable cylinder and the second rotatable cylinder are coupled to the body and configured in a predetermined position such that the opening is in communication with the passage. The valve apparatus further comprises an axle for driving the first rotatable cylinder and the second rotatable cylinder, wherein the axle is coupled to the body. The valve apparatus further includes a gear assembly having a first set of gears coupled with the first rotatable cylinder and a second set of gears coupled to the second rotatable cylinder. The first sent of gears and the second set of gears are geared to one another. In a currently preferred embodiment, the first rotatable cylinder and the second rotatable cylinder rotate in an opposite direction from one another. Alternatively, the first rotatable cylinder and the second rotatable cylinder may rotate in the same direction as one another.
In another aspect of the invention, a variable throttle valve apparatus comprises a body having a passage. A first cylinder is coupled to the body. The first cylinder has a first aperture and is configured to be moved between a first position and a second position. A second cylinder is coupled to the body. The second cylinder has a second aperture and is configured to be moved between the first position and the second position, such that he first aperture and the second aperture form a variable sized opening when the first cylinder and the second cylinder move between the first position and the second position. The variable sized opening is preferably in a closed position when the first cylinder and the second cylinder are in the first position. The body is configured to allow a predetermined amount of air to pass through the passage as the cylinders rotate from a first position to a second position. The body is configured to mate with the variable opening so as to allow a desired amount of air to pass through the passage when in the first position. The valve apparatus further comprises an axle for driving the first cylinder and the second cylinder, wherein the axle rotates in the body. The valve apparatus further comprises a gear assembly having a first set of gears that are coupled to the first cylinder. A second set of gears is coupled to the second cylinder, wherein the first sent set of gears and the second set of gears are geared to one another. The first cylinder and the second cylinder are configured to rotate in cooperation with one another, whereby the first aperture and the second aperture form a variable sized opening between the first position and the second position.
In yet another aspect of the invention, a method of assembling a variable valve apparatus comprises providing a body having a conduit, wherein the conduit is configured to have an open position and a closed position. The method comprises rotatably inserting a first cylinder into the body. The first cylinder has a first aperture and is configured to be moveable such that the first aperture is in complete communication with the conduit in the open position. The method further comprises rotatably inserting a second cylinder into the body. The second cylinder has a second aperture and is configured to be moveable such that the second aperture is in complete communication with the conduit in the open position. The first aperture and the second aperture are not in communication with the conduit when the first aperture and the second aperture are in the closed position. The body includes means for driving the first cylinder and the second cylinder, wherein the means for driving is attached to the body. The body further comprises a gear assembly which has first set of gears coupled to the first cylinder and a second set of gears coupled to the second cylinder, wherein the first set of gears and the second set of gears are geared to one another. The first cylinder and the second cylinder preferably move in an opposite direction from one another. The first and the second cylinders are preferably rotatably moveable about axes which are parallel to one another.
In yet another aspect, a valve comprises a body, a first means for channeling air through the body, and a second means for channeling air through the body. The first means and the second means are configured to rotatably more in an opposite direction from one another, thereby forming a variably sized aperture.
From the above, it may be seen that the present invention provides a means of configuring intake systems for intake combustion engines which have important advantages over butterfly valves. For example, the intake valve system may be configured for a non-circular opening at a wide open throttle, thereby being more easily mated to multi valve cylinder heads, which often do not have circular intake ports. Also, since the apertures in the cylinders may be easily varied in cross-section, it is possible to have different cross-section to rotation angles to tune the intake system as a function of throttle opening.
While the invention has been described in the context of an internal combustion intake throttle, those skilled in the art will also recognize that the principles of the engine may be applied to a variety of valve systems for engines and commercial processes and applications.
Other features and advantages of the present invention will become apparent after reviewing the detailed description of the preferred embodiments set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an intake valve system according to the invention mounted on an engine cylinder head.
FIG. 1A illustrates and exploded view of the variable valve according to a preferred embodiment of the present invention.
FIG. 1B illustrates a perspective view of one of the cylinder used in the variable valve according to the preferred embodiment of the present invention.
FIG. 2A illustrates a perspective view of the variable valve in an open position according to the alternative embodiment of the present invention.
FIG. 2B illustrates a perspective view of the variable valve in an intermediate position according to the alternative embodiment of the present invention.
FIG. 2C illustrates a perspective view of the variable valve in a closed potion according to the alternative embodiment of the present invention.
FIG. 3A illustrates a perspective view of the variable valve in an open position according to the preferred embodiment of the present invention.
FIG. 3B illustrates a perspective view of the variable valve in an intermediate position according to the preferred embodiment of the present invention.
FIG. 3C illustrates a perspective view of the variable valve in a closed position according to the preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides many benefits over prior art valve systems and may also be applied to other non-engine applications in which it is desirable to have a robust variable opening valve. While the invention will be described in a presently preferred embodiment in which the opening in the valve in a fully open position has a circular cross-section, the valve may be configured to have a non-circular cross section at a wide open position for various applications. Similarly, while the embodiments which are described illustrate a fully closed position and direct one to one gearing, both the gearing and the cylinder cross section may be changed to provide different minimum throttle openings and slopes of area vs. throttle inputs as desired.
Reference will now be made to preferred and alternative embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide an understanding of the present invention. However, it should be noted that the present invention may be practiced without these specific details. In other instances, well known methods, procedures and components have not been described in detail as not to unnecessarily obscure the aspects of the present invention.
FIG. 1 is a perspective view of a valve body 100 according to the invention mounted on a cylinder head of an internal combustion engine.
FIG. 1A illustrates an exploded view of the variable valve 100 according to the preferred embodiment of the present invention. The variable valve 100 includes a block or body 102 , a first cylinder or barrel 104 coupled to the body 102 and a second cylinder or barrel 106 coupled to the body 102 . In addition, the valve 100 includes a first gear 108 , a second gear 110 , a side piece 112 and an axle 114 . Similarly, the second gear 110 is coupled to the second cylinder 106 and also coupled to a bearing set (not shown) configured in the inner side of the side piece 112 . The axle 114 is preferably coupled to the first cylinder 104 , whereby the axle 114 extends through the side piece and the first gear 108 to the first barrel 104 . Alternatively, the axle 114 is coupled to the second barrel 106 .
As shown in FIG. 1A , the block 102 includes several apertures. On the front face of the block 102 is a first opening or passage 116 and a second opening or passage 118 . The first passage 116 extends from the front face 124 to the back face 126 . Similarly, the second passage 118 extends from the front face 124 to the back face 126 of the block 102 . The preferred embodiment shown includes two passages, such as to support different types of induction intake systems. The block 102 includes two side inserts 120 and 122 , wherein the first barrel 104 couples to the first insert 120 and the second barrel 106 couples to the second insert 122 .
As shown in FIG. 1A , the first gear 108 couples to the first barrel 104 and the second gear 110 couples to the second barrel 106 . Preferably, the first gear 108 and the second gear 110 are of the same size and dimension. Alternatively, the first gear 108 and the second gear 110 are of a different size and dimension. When the barrels 104 and 106 are positioned within the block 102 , the first gear 108 and the second gear 110 are geared together such that the rotation of one of the barrels will cause the other barrel to rotate in cooperation with the barrel. Although only two gears 108 , 110 , are shown in this example, more than two gears may be used in the event that a gear train of a different ratio is used. Alternatively, the barrels may be driven by other means, such as levers, electromechanical stepper motors or the like to accomplish the appropriate synchronized opening.
FIG. 1B illustrates a perspective view of one of the cylinders 106 used in the variable valve according to the preferred embodiment of the present invention. The barrel or cylinder 106 preferably includes a first aperture 103 and second aperture 109 . Alternatively, the number of apertures would depend on the number of passages that are present in the block, if a block is used in the valve apparatus. Alternatively, if a block is not used, the number of apertures would depend on the number of valves that are desired. The aperture 103 serves as an opening through which flow passes through. Preferably, the flow would be an air flow. Alternatively, the flow would be some other medium, such as other gases or even liquids. The aperture 103 is preferably a semicircular shape to conform to the shape of the passage 116 in the block 102 . Alternatively, the aperture 103 is any other shape or pattern, such as square, rectangular, etc. The cylinder 106 includes an axis 99 that passes through the length of the cylinder 106 , whereby the cylinder 106 is configured to rotate about the axis 99 .
FIG. 2A illustrates a perspective view of the variable valve in an open position according to the present invention. It should be noted that he block 102 has been omitted from FIGS. 2A–2C for illustration purposes, although it is not necessary that block 102 be used to practice the present invention. As shown in FIG. 2A , the barrels 204 and 206 are positioned such that the semi-circular apertures 203 and 205 form a channel or conduit which is a complete circular aperture. The channel is designated as being in the open position, because the maximum amount of flow passes through the channel. The first gear 208 and the second gear 210 are coupled to one another such that the rotation of one of the barrels will cause the other barrel to rotate in cooperation with the barrel. The rotation of the first barrel 204 causes the second barrel 206 to also rotate, thereby allowing the circular aperture to increase or decrease in dimension or diameter as the barrels rotate.
For instance, as shown in FIG. 2A , the valve 200 is shown in the open position. Applying a torque force to the axle 214 will cause the axle 214 to rotate. As shown in FIG. 2A , the rotation is preferably provided in a clockwise manner. It should be noted that the axle 214 alternatively rotates in a counter-clockwise manner. Once the axle 214 rotates clockwise, the first barrel 204 also begins to rotate clockwise about axis 99 . Since the first gear 208 is coupled to the first barrel 204 and also geared to the second gear 210 , the second gear 210 will rotate counter-clockwise along axis 98 . As described above, the second gear 210 is coupled to the second barrel 206 , therefore the second barrel 206 rotates counter-clockwise as the first barrel 204 rotates clockwise. The rotation of the first barrel 204 and the second barrel 206 causes the complete circular aperture to change in dimension, as shown in FIG. 2B .
FIG. 2B illustrates a perspective view of the variable valve in an intermediate position according to the present invention. As the first barrel 204 rotates in the clockwise manner and the second barrel 206 rotates in a counter-clockwise manner, the dimension of the channel decreases in size. This decrease in dimension prevents the maximum amount of flow to pass through the channel. Further, as shown in FIG. 2C , the variable valve 200 is in a closed position as the first barrel 204 and the second barrel 206 rotate opposite of one another even further.
FIG. 3A illustrates a perspective view of the variable valve 300 in an open position according to the preferred embodiment of the present invention. As described above in relation to FIG. 2A , the maximum amount of flow is able to pass through the channel when the first aperture 205 and the second aperture 203 are preferably configured to form a complete circular opening. Since the passage 316 and 318 of the block body 302 are preferably circular in shape, the first and second apertures 205 and 203 will be configured to be in communication with passage 316 when the valve 300 is in the open position, as shown in FIG. 3A . Similarly, the third and fourth apertures 207 and 209 are configured to be in communication with the passage 318 when the valve 300 is in the open position. Thus, the maximum amount of flow is able to flow through the passages 316 and 318 when the valve 300 is in the open position and the channel has the largest dimension.
FIG. 3B illustrates a perspective view of the variable valve 300 within the block in an intermediate position according to the preferred embodiment of the present invention. As shown in FIG. 3B , the block 302 includes two passages 316 and 318 and the first barrel 304 as well as the second barrel 306 positioned within the block 302 . The valve apparatus 300 shown in FIG. 3B is in an intermediate position, because the channel is not in complete communication with the passages 316 and 318 . Thus, an intermediate amount of flow between the minimum and maximum able to pass through the passages 316 and 318 .
FIG. 3C illustrates a perspective view of the variable valve 300 in a closed position according to the preferred embodiment of the present invention. As described above in relation to FIG. 2C , the minimum amount of flow is able to pass through the first barrel 204 and the second barrel 206 , because there is no channel though which the flow is able to pass. Therefore, only a predetermined minimum amount of flow is able to pass though the passage 316 and 318 .
The operation of the variable valve of the present invention will now be discussed in view of FIGS. 3A–3C . In the exemplary embodiment shown, the valve 300 is placed in an automobile engine, wherein the block 302 is configured such that air enters through the passages 316 and 318 on the front side 324 and exits through the passages on the back side of the block 326 . Once the air exits the block 302 , the air mixes with fuel which is discharged by the fuel injectors. In FIG. 3C , the engine is preferably in an idle state whereby the valve 300 is in a closed position. As described above, only a predetermined minimum amount of air passes between the first barrel 30 and the second barrel 306 , due to a small amount of space between the first barrel 304 and the second barrel 306 in the closed position. As the throttle is increased, the axle 314 rotates in response to the gas pedal being depressed. The rotation of axle 314 causes the first barrel 304 to rotate in the same direction as the axle 314 and along axis 99 . The first gear, which is coupled to the first barrel 304 , also rotates about axis 99 . Since the first gear and the second gear are geared together, the rotation of the first gear causes the second gear to rotate in cooperation with the first gear. As described above, the first gear and the second gear preferably rotate in the opposite direction from one another.
Alternatively, the first gear and the second gear rotate in the same direction with one another by use of a gear train (not shown).
As the second gear rotates about axis 98 , the second barrel 306 also rotates about axis 98 . As described above, the first gear and the second gear may be of the same size and dimension. Therefore, both barrels 304 and 306 rotate at the same rate and distance with respect to one another. Alternatively, the barrels 304 and 306 may be configured such that one barrel rotates at a different rate and distance from the other barrel.
As the first barrel 304 rotates with the axle 314 , the second barrel 306 preferably rotates the same distance in an opposite direction. Thus, as the axle 314 rotates further, the apertures of the first barrel and the second barrel begin to enlarge the passage due to the rotation of ht barrels, thereby forming a channel. At this point, the valve 300 is in an intermediate position, whereby some air then passes through the channels as well as the passages of the block 302 . In an electrically charged engine the engine management system in the engine can determine the desired dimension of the channel and the amount of air passing through the block 30 and cause the appropriate amount of fuel to be released and mix with the air before the mixture is sent to the cylinders.
As the throttle is further advanced, the axle 314 rotates further, thereby causing the first barrel 304 and the second barrel 306 to rotate further about their respective axes. The further rotation of the first and second barrels 304 and 306 cause the apertures to rotate such that the channel becomes larger. As the channel becomes larger, more air is allowed to pass through the passage, because there is less obstruction of the barrels in the passage. At full throttle, the first barrel 304 and the second barrel 306 are rotates such that the apertures form a circular channel that is in complete communication with the passages. The valve 300 is in an open position at this point, whereby the maximum amount of air passes through the passages and the channels. In this manner, the first barrel 304 and the second barrel 306 are rotated relative to each other to provide the appropriate amount of flow through the variable throttle valve of the present invention.
The present invention has been described in terms specific embodiments incorporating details to facilitate the understanding of the principles of construction and operation of the invention. It will be apparent to those skilled in the art that modifications may be made in the embodiments chosen for illustration without departing from the spirit and scope of the invention. Accordingly, reference herein to specific embodiments and details thereof is not intended to limit the scope of the claims appended hereto. | A variable valve comprising a first cylinder having an aperture and a second cylinder having a second aperture. The first cylinder moves between a first position and a second position. Preferably, the second cylinder moves in cooperation with the first cylinder such that the first aperture and the second aperture form a variable sized opening when the first cylinder moves from the first position toward the second position. The first aperture and the second aperture preferably rotate. The variable sized opening is preferably in a closed position when in the first position. The valve comprises a block body including a passage for allowing air to pass therethrough. The first cylinder and the second cylinder are coupled to the block body and configured in a predetermined position such that the variable sized opening is in communication with the passage. The valve also includes an axle for driving the first cylinder and the second cylinder. | 5 |
REFERENCE TO PENDING PRIOR PATENT APPLICATIONS
[0001] This patent application claims benefit of:
[0002] (i) pending prior U.S. Provisional Patent Application Ser. No. 60/878,338, filed Jan. 3, 2007 by Paul A. Chambers for SELF CONTAINED SELF RESCUER—PLUS (Attorney's Docket No. CHAMB-11 PROV);
[0003] (ii) pending prior U.S. Provisional Patent Application Ser. No. 60/925,314, filed Apr. 19, 2007 by Paul A. Chambers for SELF CONTAINED SELF RESCUER—PLUS (Attorney's Docket No. CHAMB-12 PROV); and
[0004] (iii) pending prior U.S. Provisional Patent Application Ser. No. 60/965,464, filed Aug. 20, 2007 by Paul A. Chambers for UNIVERSAL MINER SELF RESCUER (UMSR) (Attorney's Docket No. CHAMB-13 PROV).
[0005] The three above-identified patent applications are hereby incorporated herein by reference.
[0006] C.
FIELD OF THE INVENTION
[0007] This invention relates to self-contained breathing apparatuses (SCBAs) in general, and more particularly to a self-contained breathing apparatus with a safety quick disconnect for permitting safe and ready access to a replacement breathing component.
BACKGROUND OF THE INVENTION
[0008] The nature of underground mining operations makes them highly dangerous.
[0009] For example, in the case of a mine collapse, the supply of breathable air can be severely compromised, placing the miners in great danger.
[0010] Furthermore, mines are often highly susceptible to the infusion of noxious gases (e.g., methane, carbon monoxide, etc.). This situation can occur in many scenarios, even where there is no catastrophic mine collapse. Gas pockets can be exposed at any time and without notice, and can be life-threatening even where the mine is structurally intact. In any of these situations, once the gas enters the space occupied by the miners, their lives are in serious danger.
[0011] In all of these situations, the miners must quickly recognize the danger and then must obtain an supply of breathable air. This supply of breathable air may be provided by various means, e.g., a filtered system, a conventional “open-loop” self-contained breathing apparatus (SCBA), a conventional “closed-loop” self-contained breathing apparatus (SCBA), a solid state oxygen generator, etc. The equipment for providing the supply of breathable air is commonly referred to as a Self Rescuer and is generally carried by the miners on their belts. Once the miners have “switched over” to this supply of breathable air, they must then escape the danger zone. In the case of a “benign” gas pocket, escape may be as simple as walking or riding a mine car out of the affected area. In the case of a mine collapse, gas explosion, or other serious event, escape may involve crawling, tunneling, walking or just waiting for rescue. In any of these latter situations, there is a significant danger that the supply of breathable air may be depleted before the miner has reached a safe location.
[0012] At the same time, in many of these situations, it is not possible for the miners to use conventional negative pressure filtered respirators, powered air purifying respirator (PAPR), etc. due to the nature of the threat, e.g., the possible air contaminants (e.g., some gases), the physical state of the ambient air (e.g., super-heated air), etc. In these situations, a self-contained breathing apparatus (SCBA) is required.
[0013] Conventional “open-loop” SCBA units generally consist of a tank of compressed gas (usually ambient, but filtered, air) with the flow controlled by a regulator or demand valve. One of the major inefficiencies of these units is that the exhausted and/or exhaled air (still containing significant usable oxygen) is vented to the environment and thus lost to the user. Much greater efficiencies (translating into smaller, lighter units and longer supply times) can be attained by using “closed loop” SCBA units which recycle the exhaust air and recover the oxygen, and/or remove the undesirable products of respiration (mainly carbon dioxide). A device utilizing this approach is commonly referred as a “Rebreather”. See FIG. 1 .
[0014] Any respirator device, whether filtered, open-loop SCBA, closed-loop SCBA, etc. has a limited capacity to supply breathable air. If the miners exhaust the capacity of the respirator device while still in a dangerous environment, the miners must be able to access a replacement breathing component and make the “change-over” to the replacement breathing component without “breaking the seal” or otherwise exposing themselves to breathing in the potentially noxious gases.
[0015] As a result, a primary object of the present invention is to provide a self-contained breathing apparatus (SCBA) which is able to safely and quickly connect to a replacement breathing component without “breaking the seal” so that the replacement breathing component can supply additional breathing capacity to the user. Preferably, the replacement breathing component can take any number of forms, e.g., the working portion of another “closed-loop” SCBA, an air bottle, a carbon monoxide filter respirator, etc.
SUMMARY OF THE INVENTION
[0016] The present invention provides a self-contained breathing apparatus (SCBA) which is able to safely and quickly connect to a replacement breathing component without “breaking the seal” so that the replacement breathing component can supply additional breathing capacity to the user.
[0017] In one form of the present invention, there is provided a self-contained breathing apparatus (SCBA) comprising:
[0018] a mouthpiece;
[0019] a breathing component for providing breathable air, the breathing component comprising a component interface; and
[0020] a safety quick disconnect comprising:
a valve body defining:
an internal chamber; an opening communicating with the internal chamber and connectable with the mouthpiece; first and second ports communicating with the internal chamber; first and second mounts formed on the body adjacent to the first and second ports, respectively, for receiving the component interface of the breathing component, the first and second mounts being configured so as to place the breathing component into communication with the internal chamber when the component interface is in engagement with one or the other of the first and second mounts;
a valve spool selectively rotatably disposed within the internal chamber, wherein the valve spool comprises an L-shaped channel formed such that when the valve spool is appropriately rotated, the L-shaped channel (i) places the opening in communication with the first port, or (ii) places the opening in communication with the second port; and a lock mechanism for (i) preventing the valve spool from being rotated unless the component interface of the breathing component is positioned in one of the first and second mounts and a component interface of a replacement breathing component is positioned in the other of the first and second mounts, and (ii) preventing the removal of a component interface from a mount adjacent to a port which is in communication with the opening.
[0028] In another form of the present invention, there is provided a self-contained breathing apparatus (SCBA) comprising:
[0029] a mouthpiece;
[0030] a counterlung; and
[0031] a breathing component interposed between the mouthpiece and the counterlung, the breathing component being adapted to provide breathable air; wherein the counterlung is sized so as to have a volume which is approximately equal to the tidal volume of a pair of adult lungs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which are to be considered together with the accompanying drawings wherein like numbers refer to like elements and further wherein:
[0033] FIG. 1 is a schematic view showing a prior art SCBA;
[0034] FIG. 2 is a schematic diagram showing a high-level overview of a novel SCBA formed in accordance with the present invention;
[0035] FIG. 3 is a schematic diagram showing a more detailed illustration of a novel SCBA formed in accordance with the present invention;
[0036] FIG. 4 is a schematic view showing a novel breathing component formed in accordance with the present invention;
[0037] FIGS. 5-11 are schematic views showing a novel safety quick disconnect of the present invention;
[0038] FIGS. 12-14 are schematic views illustrating how a breathing component and a replacement breathing component may be simultaneously connected to the safety quick disconnect, with only one breathing component being operable at a given time;
[0039] FIGS. 15-17 are schematic views showing how a depleted breathing component may be “switched out” (i.e., changed over) to a replacement breathing component;
[0040] FIGS. 18-23 are schematic views illustrating various configurations for a novel breathing component formed in accordance with the present invention; and
[0041] FIGS. 24-27 are schematic views illustrating various types of breathing components which can be connected to the safety quick disconnect.
DETAILED DESCRIPTION OF THE INVENTION
[0042] Looking next at FIGS. 2 and 3 , there is shown a novel self-contained breathing apparatus (SCBA) 5 formed in accordance with the present invention. SCBA 5 generally comprises a mouthpiece 10 which is releasably connected to a multi-port safety quick disconnect 15 . Also connected to quick disconnect 15 is a breathing component 20 . A replacement breathing component 20 A may also be connected to quick disconnect 15 when breathing component 20 is to be replaced.
[0043] Looking now at FIGS. 2-4 , breathing component 20 preferably comprises a demand regulator 25 , a carbon dioxide scrubber 30 and a counterlung 35 . Breathing component 20 also comprises an oxygen supply 40 .
[0044] During use, the user places mouthpiece 10 in their mouth and inhales and exhales through their mouth (a noseclip may also be supplied to restrict breathing through the nose and permit breathing through only the mouth). As air is exhaled, it passes through demand regulator 25 , through carbon dioxide scrubber 30 and fills counterlung 35 . As this occurs, carbon dioxide scrubber 30 purges carbon dioxide from the exhaled air. Conversely, as air is inhaled, air is drawn from counterlung 35 , through carbon dioxide scrubber 30 , through demand regulator 25 and back into the lungs of the user. Again, as the air from counterlung 35 passes through carbon dioxide scrubber 30 , the scrubber purges carbon dioxide from the air.
[0045] Demand regulator 25 monitors the air pressure in the system and, when the air pressure falls below a certain threshold, releases supplemental oxygen from oxygen supply 40 . More particularly, as the user breathes, the body metabolizes oxygen and releases carbon dioxide. This carbon dioxide is then removed from the system by carbon dioxide scrubber 30 . Therefore, in a “closed-loop” system, as the user breathes, oxygen is consumed by the user, carbon dioxide is consumed by the scrubber, and the quantity of air is reduced. To that end, demand regulator 25 monitors the air pressure in the system and, as the quantity of air is reduced during breathing and scrubbing (which also reflects a reduction in the quantity of oxygen available for breathing), demand regulator 25 releases supplemental oxygen to the system to compensate for the consumed gases.
[0046] As a result of this construction, breathing component 20 is designed to provide extended breathing capacity, due to the use of (i) carbon dioxide scrubber 30 , which allows the re-breathing of exhaled air, and (ii) demand regulator 25 and oxygen supply 40 , which supply supplemental oxygen to the system as oxygen is consumed through breathing.
[0047] Significantly, counterlung 35 is carefully configured so as to have a size approximately equal to tidal volume of a pair of human lungs. This is approximately three times smaller than traditional counterlungs. By configuring counterlung 35 with this unique size, breathing component 20 ensures that demand regulator 25 will release fresh oxygen to the system before the oxygen content of the air being re-breathed falls to a level which is too low to safely sustain the user. More particularly, with each breath of the user, approximately 20% of the oxygen inhaled is consumed by the body and is replaced with exhaled carbon dioxide. This exhaled carbon dioxide is in turn purged by carbon dioxide scrubber 30 . Thus, in the absence of a supplemental oxygen source, as the user breathes, the total quantity of air will continuously decrease as the carbon dioxide is pulled from the air. If counterlung 35 is made too large, it will take too long for the quantity of air in the system to be depleted to the point where demand regulator 25 will trigger the release of supplemental. oxygen from oxygen supply 40 . On the other hand, if counterlung 35 is formed too small, a user will not be able to inhale and exhale a full breath, which is important in emergency breathing situations where the user may need to be moving about rapidly. Sizing counterlung 35 so as to be the approximately the size of the tidal volume of a pair of lungs is a new and significant advance in the art.
[0048] In another significant advance over the prior art, SCBA 5 utilizes a multi-port safety quick disconnect 15 to permit replacement breathing component 20 A to be safely and quickly connected to mouthpiece 10 without “breaking the seal”, so that additional breathing capacity can be safely supplied to the user when necessary. More particularly, any breathing component (e.g., a “closed-loop” SCBA system, a carbon dioxide absorber, an oxygen tank, etc.) has a finite functional lifetime: at the end of that functional lifetime, the breathing component must ultimately be replaced with a fresh unit in order to sustain a user. The present invention provides novel multi-port safety quick disconnect 15 to permit replacement breathing component 20 A to be safely and quickly connected to mouthpiece 10 without “breaking the seal”, so that additional breathing capacity can be safely supplied to the user when necessary
[0049] Safety disconnect 15 is shown in greater detail in FIGS. 5-11 . Safety disconnect 15 generally comprises a hollow rectangular valve body 45 having a top opening 48 for connecting to mouthpiece 10 , two faces 50 , 55 ( FIGS. 6 and 9 ) with ports 60 , 65 formed therein, respectively, and a back plate 67 for closing off valve body 45 . The faces 50 , 55 are each configured with a U-shaped rail 70 for slidably receiving, and forming an airtight seal with, a component interface 75 which connects with a breathing component. A cylindrical valve spool 80 , with an L-shaped channel 85 formed therein, is rotatably disposed within valve body 45 . A selection knob 90 is provided to permit the user to adjust the rotational position of valve spool 80 within valve body 45 . As a result of this construction, L-shaped channel 85 can be used to connect port 60 with opening 48 or, alternatively, port 65 with opening 48 .
[0050] Significantly, means are provided for restricting the position of valve spool 80 within valve body 45 , and for restricting the inadvertent removal of a component interface 75 from valve body 45 , whereby to present a user from accidentally breathing ambient air.
[0051] More particularly, back plate 67 includes a locking clip 95 having a pair of projecting spring fingers 100 . Valve spool 80 includes four recesses 105 formed therein for selectively receiving spring fingers 100 of locking clip 95 . As a result of this construction, valve spool 80 may not be rotated within valve body 45 unless, and until, two component interfaces 75 are pressed sufficiently rearwardly within U-shaped rail 70 as to push the two corresponding projecting spring fingers 100 out of their corresponding spool recesses 105 .
[0052] Furthermore, selection knob 90 is provided with a peripheral extension 110 along a portion of its perimeter which prevents accidental removal of the component interface 75 selected by and in use on that corresponding side of the valve body so as to prevent the user accidentally disconnecting the active breathing air supply and exposing the corresponding port 60 , 65 to atmosphere.
[0053] In addition to the foregoing, valve spool 80 is formed so that when it is in a locked position (i.e., so that a spring finger 100 is received in a spool recess 105 ), L-shaped channel 85 is connecting either port 60 with opening 48 or port 65 with opening 48 .
[0054] As a result of this construction, a component interface 75 may only be withdrawn when another component interface 75 has been connected to quick disconnect 15 and valve knob 90 has been rotated to select the side being retained as a breathing source. Furthermore, as shown in FIGS. 12-14 , only one port 60 , 65 may be open at any given time to mouthpiece 10 . Thus, the mouthpiece can never be opened to ambient air. As a result, multi-port safety quick disconnect 15 permits a replacement breathing component to be safely and quickly connected to mouthpiece 10 without “breaking the seal”, so that additional breathing capacity can be safely supplied to the user. In other words, a user cannot disconnect from a current breathing component unless, and until, a replacement breathing component has been properly connected to multi-port quick disconnect 15 . Thus, the construction quick disconnect 15 prohibits a user from (i) accidentally disengaging a current breathing component until a replacement breathing component has been connected, and (ii) inadvertently connecting the mouthpiece to ambient air.
[0055] In other words, the foregoing construction permits a first breathing component is to be safely and readily replaced with a replacement breathing component when necessary. More particularly, and looking now at FIGS. 15-18 , safety quick disconnect 15 permits a first breathing component 20 to be replaced with a replacement breathing component 20 A, and the first breathing component 20 to be thereafter discarded.
[0056] Looking next at FIGS. 18-21 , it will be seen that quick disconnect 15 can be rotatably positioned in a variety of a configurations vis-à-vis breathing component 20 so as to provide a desired profile, e.g., so as to facilitate wearing on a belt, attachment to alternative breathing component, etc. Furthermore, breathing component 20 can have an ergonomic exterior shape so as to facilitate wearing it on a belt, e.g., the body of breathing component 20 can have a kidney-shaped cross-section and counterlung 35 can have a flat shape (when empty), etc. See, for example, FIG. 22 .
[0057] If desired, and as shown in FIGS. 23 and 24 , quick disconnect 15 can be use to switch off between two identical breathing components 20 , 20 A. Alternatively, quick disconnect 15 can be connected to various other types of breathing components of the sort well known in the art, e.g., a carbon monoxide absorber 20 B ( FIG. 25 ), an oxygen bottle 20 C ( FIG. 26 ), etc. See also FIG. 27 .
MODIFICATIONS
[0058] While the present invention has been described in terms of certain exemplary preferred embodiments, it will be readily understood and appreciated by those skilled in the art that it is not so limited, and that many additions, deletions and modifications may be made to the preferred embodiments discussed herein without departing from the scope of the invention. | A self-contained breathing apparatus (SCBA) comprising: a mouthpiece; a breathing component; and a safety quick disconnect comprising: a valve body; a valve spool comprising an L-shaped channel formed such that when the valve spool is appropriately rotated, the L-shaped channel (i) places an opening of the valve body in communication with a first port, or (ii) places the opening in communication with a second port; and a lock mechanism for (i) preventing the valve spool from rotating unless the breathing component is positioned in one of first and second mounts formed on the valve body adjacent the first and second ports, and a replacement breathing component is positioned in the other of the first and second mounts, and (ii) preventing the removal of a breathing component from a mount adjacent to a port which is in communication with the opening. | 0 |
[0001] This application is entitled to and hereby claims the priority of co-pending U.S. Provisional application, Ser. No. 60/519,252 filed Nov. 13, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is related to the field of inter-computer networking and more particularly to a methodology and/or protocol that requires network header metadata, such as access control identifiers (ACIs), to be transitioned and operated upon among a plurality of separately defined computer network domains. The present invention is also related to the field of encrypted computer network communication and, more particularly, to a methodology for implementing functions that require unencrypted data in a secure computer network.
[0004] 2. Description of the Related Art
[0005] A network typically requires the transmission of access control identifiers (ACIs) at various layers of a communication stack to enable successful completion of an end-to-end (E2E) transmission. Across that E2E path, however, are various service facilities that utilize the ACIs, whether in the header or embedded in the payload, for functions such as routing, inspection, user or location identification, forwarding, etc. When such a service facility, e.g., a proxy server, post office or other application-based traversal mechanism, is utilized, the ACIs are lost and are no longer available to a session protocol. This loss of ACIs, for example in IP identifiers, occurs due to the layer mechanisms inherent in the protocol stack. Specifically, the processing elements operating at a particular layer can operate only on ACIs available to that particular layer and not at layers above or below. As a result, the intervening service facility causes services such as access control capability to be lost and/or terminated, leaving only routing data available for reuse.
[0006] Various prior art methods have been proposed which teach that a singular self-contained service can be used to inspect the payload and compare it against a store of known rules prior to forwarding. Service facilities disclosed for such methods can operate on predefined network topologies and are used within these topologies to provide some service, e.g. forwarding or inspection. These prior art approaches provide no inheritance of the ACIs across services within the communications path and are limited to cascading services performed within a single network domain.
[0007] In sum, existing service facilities within networks are uni-directional, self-contained and/or require known network-specific topologies. Services based on the existing art have limited session facilities on the network, requiring service functions to be embedded within the application itself or within a series of applications as part of the application codes/functions. Session persistence is only maintained by the application and is otherwise terminated when the session-layer ACIs are lost between applications or service facilities. The existing art does not provide service mechanisms that allow bi-directional movement of the ACIs as is required in a session-based service.
[0008] Additionally, a secure computer network requires the transmission of encrypted data with associated ACIs from a data source to a specified data destination. However, many computer network functions such as intrusion detection, load balancing, TCP/IP acceleration, etc. need to operate on cleartext or unencrypted data and will not perform properly when processing encrypted data. Thus, functions requiring cleartext, when embedded within a conventional secure network, do not perform properly.
[0009] A mechanism for providing access control on network communications used by the Department of Defense is to place identifiers on Internet Protocol (IP) data streams. These identifiers can be checked at the source and destination host machines to determine if the sender can send that type of information and whether the receiver can receive that type of information. In a standard client server environment, where all systems between the two host systems operate only on the IP layer, this access control mechanism has been shown to work well and has many government approvals for its operation.
[0010] However, when a proxy, service facility or other application-based traversal mechanism is utilized, IP identifiers that are placed on the individual packets are lost and thus network-level access control mechanisms cannot be utilized. This loss is consistent with the operation of the standard TCP/IP and IPsec protocol stacks which operate in a layered fashion where processing elements operating at a particular layer can see all data at that level and above, but none below. Since the proxy/application is at the application layer, it cannot generally see information at the IP layer.
[0011] Therefore, a need exists for a system and method by which header data at different layers of the communications protocol stack is maintained throughout a network session that traverses multiple networks and domains.
SUMMARY OF THE INVENTION
[0012] In view of the foregoing, one object of the present invention is to provide a session-level bridging mechanism to retain, operate on and forward ACIs across a plurality of functionalities.
[0013] Another object of the present invention is to provide an inter-networking method that provides for metadata utilization for the life of a session even on unknown networks being traversed, allowing for metadata utilization, reutilization, and modification in both the send and receive paths (bi-directional), and allowing for transport over segments requiring that ACIs be embedded at different layers of the communications stack.
[0014] A further object of the present invention is to provide a session-level service-to-service mechanism that traverses from within one network domain to other known or unknown network domain, enforcing and utilizing header metadata across the combined inter-network.
[0015] A still further object of the present invention is to provide an inter-networking service-to-service mechanism that allows ACIs to be transmitted and utilized among networks where the method of transfer of the ACIs may be at different layers of the network stack.
[0016] Yet another object of the present invention is to provide a mechanism to retain ACIs across a functionality that requires cleartext within an encrypted communication.
[0017] A still further object of the present invention is to provide a function embedding unit including an ACI virtual private network (VPN) that performs decryption and retains the ACIs, and an ACI VPN that performs encryption and reinserts the ACIs which were traversed across an embedded function requiring non-encrypted data.
[0018] In accordance with these and other objects, the present invention is directed to a session-level bridging mechanism to retain, operate on and forward ACIs across a plurality of functionalities. This plurality of functionalities defines a session as utilized on multi-tier applications that operate across multiple E2E network services. In this manner, a service-to-service protocol invention, with an accompanying retention store that allows ACIs to transition from one peer-to-peer connection to another peer-to-peer connection, is defined. As a session protocol, the present invention is utilized bi-directionally, both on the forward communication path as well as on the return path, without requiring any application awareness or internal mechanisms to transition between network connections. As used herein, this service-to-service mechanism is referred to as the F-Function.
[0019] The F-Function according to the present invention is a session protocol, and becomes a network service for application developers who can thread and bind multiple existing applications (processes) and directories, or any other network service, into a cohesive transaction without application awareness or modification.
[0020] The present invention may be used advantageously in multi-tier applications that are prevalent in service-oriented architectures or web-service architectures. For example, a content-based access control may be enforced across a multi-tier structure. In the first connection of the session, the client connects to the application tier with network or data ACIs transported in the IP option field. The ACIs are then re-utilized by the application server to connect to a database server. The service facility, having maintained the session data including the ACIs, utilizes an F-Function that applies rules based on the received ACIs so that the proper data at the database server, i.e., data having content which the client is authorized to receive in accordance with the established content-based access control, is accessed and returned to the application server for forwarding to the client.
[0021] The present invention may also be used advantageously to allow an encrypted network that requires an intermediate node to utilize cleartext functions, such as inspection, by maintaining the ACIs through the application of the F-Function. The F-Function is able to first read the ACIs from the inbound IP stream, retain the ACIs during the inspection processing, and then to place the ACIs on each outbound IP stream such that there is no loss of the ACIs originally placed on the data packets due to the decryption mechanism.
[0022] Thus, the present invention also provides a mechanism to terminate IP/IPsec data streams that contain ACIs at the device, read and store the ACIs from the inbound IP packets, provide these identifiers on the outbound IP packets and utilize the identifiers to instantiate a secure channel with the destination system.
[0023] The F-Function protocol and mechanism according to the present invention provides a new network mechanism for creating session controls across an inter-network of networks rather than requiring application-aware internal controls to accomplish session connectivity.
[0024] These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a block diagram of a multi-domain network connection system that provides multiple service facilities across an E2E session where an F-Function embeds, stores, forwards and processes ACIs between service facilities on both forward and return paths, according to a first embodiment of the present invention.
[0026] FIG. 2 is a block diagram of the architecture of the F-Function services within the service facilities, according to the present invention.
[0027] FIG. 3 is a block diagram of the process flow through multiple F-Function services operating within a single service facility and includes multiple E2E connections within the session, according to the present invention.
[0028] FIG. 4 is a block diagram of the process flow through multiple F-Function services operating among multiple service facilities and includes multiple E2E connections within the session, according to a further embodiment of the present invention.
[0029] FIG. 5 is a block diagram of the modular design of the service facility providing F-Function based services of FIGS. 1-4 .
[0030] FIG. 6 is a block diagram of an F-Function transitioning method for transporting ACIs from one connection to another connection at the same layer of the communications protocol stack, according to the present invention.
[0031] FIG. 7 is a block diagram of an F-Function transitioning method for transporting ACIs from one connection at a first layer to another connection at a higher layer of the communications protocol stack,according to the present invention.
[0032] FIG. 8 is a block diagram of an F-Function transitioning method for transporting ACIs from one connection at a first layer to another connection at a lower layer of the communications protocol stack, according to the present invention.
[0033] FIG. 9 shows a block diagram of an embodiment for embedding functions requiring cleartext within a secure network that provides encryption, according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms 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.
[0035] The specific configurations described in the proceeding discussion of the present invention are illustrative of the invention's methods and in fact these methods can be used to construct many complex structures and topologies and are building blocks for a network.
[0036] As shown in FIG. 1 , the present invention is directed to a system and a methodology/protocol for enabling interconnected networks, each defined as a separate domain 51 , 52 , 53 , 54 , to carry, replicate and reutilize ACIs within the packet headers across the multiple domains 51 - 54 along communications path 100 . Service facilities 11 , 12 , 13 within these networks provide various services, such as inspection, and also provide for the forwarding of ACIs.
[0037] FIG. 1 illustrates specific network service applications 21 , 22 , 23 that are incorporated into self-contained network service facilities 11 , 12 , 13 and which provide one or more inter-service mechanisms referred to as F-Functions 61 , 62 . These specific service applications 21 , 22 , 23 in conjunction with the F-Functions 61 , 62 provide the bridging transport mechanism and retention capabilities for ACI utilization and re-utilization across a plurality of networks and computer applications (nodes) typically utilized in a session. The service facilities also provide the capability to transfer the ACIs at different layers of the communications stack 99 of communications path 100 (see FIGS. 6-8 ).
[0038] The F-Functions 61 - 64 operate within or across one or more service applications 21 , 22 , 23 , 32 , 33 in one or more service facilities 11 , 12 , 13 as shown in FIGS. 2-4 . These service applications can occur in the same or different network domains 51 - 54 . Within service facility 11 , “service A” 21 and “service B” 31 are two of any number of service applications that may be included within a given service facility. As shown in FIG. 5 , these service applications, directed by a service manager 20 , generally include ACI forwarding services, ACI retention storage services, ACI transformation rules services (e.g. tagging, modification), and ACI rules-based forwarding services (based on retention data, e.g. modified ACIs).
[0039] In the architecture shown in FIG. 2 , “service A” 21 is operating in the forward path. Within facility 12 , “service B” 32 is another service application that can be the same, similar to or a different ACI service application from that of “service A”. “Service B” 32 of service facility 12 is operating in the return path.
[0040] FIGS. 3 and 4 illustrate the ability of the present invention to interconnect service applications 21 , 22 , 31 , 32 within a service facility 11 and among service facilities 11 , 12 , respectively. FIG. 4 further illustrates implementation of the invention when an intervening application 9 exists between service facilities 11 , 12 .
[0041] FIG. 3 illustrates an inter-connecting services method that utilizes F-Function 65 for inspecting, modifying/translating, storing and forwarding of ACIs. The method can equally be applied when ACIs are embedded within the payload instead of in the header or when ACIs are in differing layers within the headers. FIG. 3 further illustrates multiple session service applications 21 , 31 in a single domain 51 within a single service facility 11 . FIG. 4 goes on to illustrate the present invention in multiple domains 51 , 52 and with multiple service facilities 11 , 12 , each having multiple session service applications 21 , 22 , 31 , 32 .
[0042] In FIG. 3 , a client computer/data source 7 a transmits a communications request over a communications channel 100 a to destination 8 b. The service facility 11 with intermediary destination node 8 a intercedes and performs a service on the request prior to re-transmittal of the request from intermediate data source node 7 b. Upon receipt of the request, the service facility 11 retains the session's ACI metadata (or other metadata) at the “service A” 21 ACI store 41 and also utilizes the F-Function 65 to transfer the ACIs from the “service A” 21 ACI store 41 to the “service B” 31 ACI store 44 , where the ACIs are retained for possible use by the “service B” 31 or other service applications later in the session's path. Any of the service applications within the service facility 11 can be applied in this store-then-forward process. The service facility 11 also utilizes the F-Function 65 to place ACIs (or other metadata) back on the outbound communications channel 100 a for connection to the data's destination 8 b.
[0043] Once the service facility 11 has acted upon the client's request from source 7 a for delivery or request for reply (request for data or processing on data), the request is forwarded to the destination 8 b. The session is then terminated if the request was only for a delivery service. In the event that data was requested, however, the session continues with a reply to the originating client 7 a.
[0044] Still with reference to FIG. 3 , when data or data processing has been requested, the reply with the requested data in its payload is transmitted on the return path, communications channel 100 b, from the original client destination 8 b back to the client, source 7 a. The service facility 11 again intercedes, with “service B” 31 applying the designated service applications on the stored ACIs retrieved from the “service B” 31 ACI store 44 , and utilizing the F-Function 65 to place ACIs (or other metadata) back on the communication channel 100 b for connection to the data's return destination, namely source 7 a.
[0045] FIG. 4 illustrates two additional elements of the present invention. First, FIG. 4 illustrates how F-Functions 61 , 63 , 65 , 66 are utilized when cascading inter-connecting service applications 21 , 22 , 31 , 32 are required in a multi-domain 51 , 52 network. Secondly, FIG. 4 also illustrates use of the present invention where a multi-tier application processing architecture is in use between service facilities 11 , 12 . Cascading inter-connecting services operate independently, with or without an application 9 in the communications path 100 .
[0046] In FIG. 4 , the client computer/data source 7 a transmits a communications request over the forward (or outbound) communications channel 100 a to application server 9 and destination 8 b within network domain 52 . The service facility 11 with intermediate destination node 8 a intercedes prior to delivery to the application server 9 , and retains the session's ACI metadata (or other metadata) at “service A” 21 ACI store 41 . The service facility 11 applies the designated service applications on the request and forwards the extracted ACIs to the “service B” 31 ACI store 44 for later session use. The service facility 11 also utilizes the F-Function 61 to transfer ACI metadata from the domain 51 “service A” 21 ACI store 41 to the domain 52 “service A” 22 ACI store 42 where the ACI metadata is retained and can be utilized by domain 52 “service A” 22 service applications later in the session's path. Any of the service applications within the service facilities 11 , 12 can be applied in this store-or-forward process.
[0047] In both FIGS. 3 and 4 , as well as any other implementations of the present invention, the transfer of the ACIs from the “service A” ACI store 41 to the “service B” ACI store 44 may occur by “pushing” thereof as has already been described. Alternatively, this transfer may be deferred, with only the ACI store 41 retaining the ACIs on the inbound path. Then, when a reply has been requested and is returned along the return communications path 100 b, the “service B” service application may “pull” the ACIs retained in the ACI store 41 to the ACI store 44 for use on the return path. Such “push” and “pull” technologies for information retrieval and forwarding are known to persons of ordinary skill in the art.
[0048] Furthermore, while the ACI stores 41 , 42 , 44 , 45 are shown herein as separate storage areas for the purposes of clarity in description, these areas are logical stores and may in fact be embodied together in a single memory device as would be known by persons of ordinary skill in the art.
[0049] Continuing with FIG. 4 , the service facility 11 further utilizes the F-Function 65 to transfer ACI metadata from the domain 51 “service B” 31 ACI store 44 to the domain 52 “service B” 32 ACI store 45 where the ACI metadata is retained and can be utilized by domain 52 “service B” 32 service applications in the next connection in the session along communications path 100 . Any of the service applications within the service facilities 11 , 12 as described above can be applied in this store-or-forward process.
[0050] Finally, the service facility 12 utilizes the F-Function 63 to place ACIs (or other metadata) on the communication channel 100 a in domain 52 for connection to the data's destination 8 b.
[0051] At this point the client's request for data from source 7 a in domain 51 has been forwarded to its destination 8 b in domain 52 and is processed. In addition to the forward communication service applications 21 , 22 there are return communication service applications 31 , 32 as part of the overall session illustrated in FIG. 4 . In a similar manner to the forwarding of ACI/metadata, the retained ACIs within the stores 41 , 42 , 44 , 45 can be reutilized on the return communication path 100 b. The F-Functions 63 , 65 , 66 continue to be utilized to transfer the ACIs between service applications 21 , 22 , 31 , 32 and their associated storage areas 41 , 42 , 44 , 45 across the service facilities 11 , 12 on the return path 100 b.
[0052] Continuing in FIG. 4 , a reply with the requested data in its payload is transmitted on the return path, communications channel 100 b, from the original destination 8 b back to the client, source 7 a. The service facility 12 intercedes by utilizing domain 52 “service B” 32 , and applies the designated service applications from the retained ACIs at the “service B” 32 ACI store 45 prior to delivery to the application server (business application) 9 where the reply is then processed. The service facility 12 utilizes the F-Function 66 to transfer ACIs from the domain 52 “service B” 32 ACI store 45 to the domain 51 “service B” 31 ACI store 44 where the ACI metadata is retained and can be utilized by service facility 11 service applications in domain 51 in the next connection in the session's path.
[0053] After processing by application 9 , the domain 52 service facility 12 utilizes the F-Functions 63 , 66 to place ACIs (or other metadata) on the communication channel 100 b for connection to the data's return destination, source 7 a.
[0054] Once back in domain 51 , the intervening service facility 11 utilizes domain 51 “service B” 31 and applies the designated service applications on the retained ACI retrieved from the “service B” 31 ACI store 44 prior to delivery of the reply to the client 7 a. The service facility 11 also utilizes the F-Function 65 to place ACIs (or other metadata) on the communication channel 100 b for connection to the data's return destination, source 7 a.
[0055] As generally applicable to both FIGS. 3 and 4 , ACI re-utilization may be filtered if an ACI rules-based service application is incorporated in the service. Furthermore, the ACI stores 41 , 42 , 44 , 45 contain the ACIs from other services 21 , 22 , 31 , 32 in the services facilities 11 , 12 from the outbound (forward) path and metadata from the inbound (return) path which are placed in the headers of the next link in the communications path unless filtered by a rules-based service application.
[0056] Also, as generally applicable to both FIGS. 3 and 4 , the session end-point terminates the ACI utilization, after which ACI metadata is no longer maintained. Multi-request sessions operate as independent requests for utilization of the F-Function facilities that are provided by the present invention.
[0057] FIG. 5 details the modular structure of a service facility 11 , the same structure being applicable to service facilities 12 , 13 , etc. The service facility includes an ACI policy manager 17 , a session service manager 20 with multiple service applications 21 , 31 (A, B, C . . . n), and a communications channel manager 13 .
[0058] The ACI policy manager 17 manages the organization and schema of the ACIs, and provides rules that can be applied to the ACIs, including administrative and metadata maintenance rules insertion, deletion and modification facilities. These rules are preferably input using a policy manager console 200 . The ACI policy manager 17 also provides ACI reader 18 and ACI writer 19 services.
[0059] The ACI reader facility 18 allows for the transfer of the ACI metadata from the communications channel manager 13 to the ACI policy manager 17 . The ACI writer facility 19 allows for the transfer of the ACI metadata from the ACI policy manager 17 to the communications channel manager 13 for transfer to another service facility 12 or for transfer of data from the ACI policy manager 17 to the ACI store 41 , 44 .
[0060] The communications channel manager 13 provides header reader 14 and header writer 15 services. The header reader 14 service interprets the header data at various layers of the communications stack 99 and forwards it to the ACI policy manager 17 . The header writer 15 service transfers ACIs from the ACI store 41 utilizing the ACI policy manager 17 and then creates the header data at various layers of the communications stack 99 .
[0061] The services described in FIG. 5 are used to read and write at various layers within the header communications stack 99 through the header reader 14 and header writer 15 services. These services provide inter-stack services capability for networks that must be transitioned across during the session but which operate at different layers within the communications stack 99 , even when encryption and deencryption services must also operate and occur at different communication layers.
[0062] In FIGS. 6-8 , the ability of the service facility 11 to transfer ACIs at the same or a different layer of the header communications stack 99 using one or more F-Functions 67 , 68 , 69 is illustrated. Layered network mechanisms representative of those currently in use include ethernet, Internet protocol (IP), traverser and original data.
[0063] First, as illustrated in FIG. 6 , the service facility 11 may be utilized to receive ACIs from the headers at layer 3 (or any other layer) within the stack 99 on the incoming communications path 100 and to transmit the same, modified or filtered ACIs on an outgoing communications path 100 in the headers at the same layer of the communications stack.
[0064] Second, the service facility 11 may be utilized to receive ACIs from the headers at layer 3 (or any other layer) within the stack 99 on the incoming communications path 100 and to transmit the same, modified or filtered ACIs on an outgoing communications path 100 in the headers at a higher layer of the communications stack, representatively layer 4 , as illustrated in FIG. 7 .
[0065] Third, the service facility 11 may be utilized to receive ACIs from the headers at layer 3 (or any other layer) within the stack 99 on the incoming communications path 100 and to transmit the same, modified or filtered ACIs on an outgoing communications path 100 in the headers at a lower layer of the communications stack, representatively layer 2 , as illustrated in FIG. 8 .
[0066] As described herein, the present invention may be used in multi-tier applications that are prevalent in service-oriented architectures or web-service architectures to enforce a content-based access decision across a multi-tier structure. In the first connection of the session, the client may connect to the application tier with network or data ACIs transported at the nework layer (layer 3 ). These ACIs are retained by an intervening service facility and then re-utilized by the application server to connect to a database server, with the service facility utilizing an F-Function that applies rules based on the received ACIs so that the proper data at the database server is accessed and returned to the application server while retaining the session data applied by the F-Function as ACI data to the client connection. With the present invention, ACI data can be transitioned by any layer in the communications stack, for any layer above that layer that does not transition such data.
[0067] As shown in FIG. 9 , the present invention is further directed to a system and methodology for enabling computer network functions requiring cleartext, such functions being designated herein by the letter FX, to be embedded and effectively operated within a secure network that provides encryption, while retaining associated ACIs from the data source to the data destination.
[0068] Inbound IP data streams are initiated by a data source 101 . Associated with the data source 101 , is a first ACI virtual private network (VPN) 201 that encrypts the data at the data source 101 and includes all associated network information, including data source and destination-peculiar ACIs.
[0069] An embedding unit 301 receives the inbound encrypted data from the first ACI VPN 201 . The embedding unit 301 includes a second ACI VPN 321 at the input, an embedded FX function 341 , and a third ACI VPN 361 at the output. In order to read the ACIs that are placed on the IP data stream, the embedding unit 301 is able to first read the identifiers from each inbound IP stream and then to place these identifiers on each outbound IP stream such that the ACIs originally placed on the data packets are not lost.
[0070] Thus, according to the present invention, the second ACI VPN 321 performs decryption on the incoming data. The ACIs extracted from the decrypted data are stored in a storage device such as a table or other storage element. The FX function 341 is injected, such FX function operating upon the decrypted data such that the FX function is performed correctly, with the stored ACIs being traversed across the FX function without interfering therewith. At the output of the embedding unit 301 , the third ACI VPN 36 then re-encrypts the data stream and re-introduces the traversed ACIs into the outbound encrypted data stream for effective network level access control.
[0071] A fourth ACI VPN 401 decrypts the data in the outbound data stream at the data destination 501 and uses the ACIs, which have been successfully maintained through the operation of the embedding unit 301 , to ensure proper delivery.
[0072] As described, the present invention provides a mechanism by which IP/IPsec data streams that contain access control identifiers are terminated at the embedding unit without loss of the ACIs. The data from the inbound IP packets is unencrypted and the ACIs associated therewith are read and stored. The FX function injected in the data stream is performed on the cleartext, after which the data is again encrypted and the stored ACIs are subsequently reintroduced to the outbound IP packets to instantiate a secure channel with the destination system.
[0073] The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. The invention may be implemented in a variety of configurations and is not limited by the configurations illustrated herein. Numerous applications of the present invention in connection with network communications will readily occur to those skilled in the art. Therefore, it is not desired to limit the invention to the specific examples disclosed or the exact construction and operation shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | An inter-networking system and method that provides for access control identifier (ACI) metadata utilization for the life of a session even on unknown networks being traversed, allowing for ACI metadata utilization, reutilization, and modification in both the send and receive paths (bi-directional), and allowing for metadata transport over network segments requiring that ACIs be embedded at different layers of the communications stack. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a rubber composition for a magnetic encoder, and a magnetic encoder using the same. Specifically, the invention relates to a magnetic rubber composition for a magnetic encoder that has a high magnetic force and is improved in heat resistance, oil resistance and chemical resistance. Also, the invention relates to a magnetic encoder using said magnetic rubber composition for a magnetic encoder.
[0003] 2. Description of the Related Art
[0004] A rubber magnet for use in sensors is used in a magnetic encoder for use in rotation speed sensors.
[0005] Among rotation speed sensors, a rubber magnet is used for magnetic encoder parts in a wheel speed sensor of motor vehicles, and nitrile rubber (NBR) or hydrogenated nitrile rubber (HNBR) is usually used in the rubber component. The rubber is described in claims and embodiments in International Patent Publication No. WO 01/041162.
[0006] However, applications of NBR having an upper limit of the heat resistant temperature of about 120° C. and HNBR having an upper limit of the heat resistant temperature of about 140° C. to around automobile engines are restricted, since the temperature of the environment where the rubber is used is as high as 130 to 170° C.
[0007] While silicone rubber, acrylic rubber, and the like can be used at about 130 to 170° C., silicone rubber is poor in oil resistance. On the other hand, release of a molded acrylic rubber is difficult when a magnetic powder is filled in a high concentration, and the die is evidently contaminated to cause poor processability.
[0008] The rotation speed sensor is used not only for the wheel speed sensor, but also for various uses such as a rotation angle sensor of a steering, a shaft rotation motor of, for example, an electric motor and a flow rate control sensor of, for example, a pump.
[0009] Accordingly, it is desirable for the rubber magnet for the sensor to have a high residual magnetic flux density. A higher residual magnetic flux density of the rubber magnet for the sensor permits the distance between the sensor and encoder to be large. Since the large distance allows the tolerance of assembly for assembling a system to be large, freedom of design is enhanced to make various applications as described above to be more advantageous.
[0010] However, although it is possible in the rubber ferrite using conventional ferrites to increase the residual magnetic flux density by increasing the amount of filling of the ferrite, hardness of the rubber also increases when the amount of filling of the ferrite is too large to cause a remarkable decrease in processability.
[0011] An attempt to increase heat resistance causes a decrease in oil resistance, or an attempt to obtain good magnetic characteristics leads to poor processability in the conventional rubber composition for the magnetic encoder and in the magnetic encoder using the rubber composition. The conventional rubber composition for the magnetic encoder and magnetic encoder using the composition have not always been satisfactory in terms of heat resistance, oil resistance, magnetic characteristics as the magnetic encoder, and processability.
SUMMARY OF THE INVENTION
[0012] Accordingly, an object of the present invention is to provide a rubber composition for the magnetic encoder being excellent in durability such as heat resistance, oil resistance and chemical resistance as well as in magnetic characteristics while the rubber composition has good processability. And another object of the present invention is to provide a magnetic encoder using said rubber composition, so that it is excellent in durability such as heat resistance, oil resistance and chemical resistance as well as in magnetic characteristics.
[0013] In order to solve the above problems, a rubber composition for a magnetic encoder according to the present application includes a fluorinated rubber with a Mooney viscosity (ML1+10, 121° C.) of 20 to 100 and a magnetic powder, while the magnetic powder is blended in a proportion of 230 to 1900 parts by weight relative to 100 parts by weight of the fluorinated rubber.
[0014] The before described rubber composition for the magnetic encoder of the present invention using the fluorinated rubber (FKM) is excellent in durability such as heat resistance, oil resistance and chemical resistance.
[0015] The fluorinated rubbers (FKM) that can be used are any copolymer rubbers represented by binary polymers including vinylidene fluoride and hexafluoropropylene, and by ternary polymers including at least three components selected from vinylidene fluoride, hexafluoropropylene, tetrafluoroethylene, perfluoromethyl vinylether and other commonly used copolymerizable fluorinated compounds.
[0016] For example, various commercially available products such as elastomer E430 (trade name, manufactured by Dupont-Dow Co.), and DAI-EL G-712, DAI-EL G-714, DAI-EL G-716 and DAI-EL LT-302 (trade names, manufactured by Daikin Industries, Ltd.) may be directly used as fluorinated rubber included in the rubber composition for a magnetic encoder of the present invention, provided that it has a Mooney viscosity (ML1+10, 121° C.) of 20 to 100.
[0017] The fluorinated rubber used for the rubber composition for the magnetic encoder of the present invention is excellent in mold processability due to large fluidity of the rubber composition when the Mooney Viscosity is lower. However, contamination of the die at the time of molding becomes evident when the Mooney viscosity (M1+10, 121° C.) is less than 20 to decrease productivity. Processing such as kneading work becomes remarkably difficult, on the other hand, when the Mooney viscosity (M1+10, 121° C.) exceeds 100. Accordingly, the rubber composition for the magnetic encoder excellent also in processability can be provided by using a fluorinated rubber with a Mooney viscosity (M1+10, 121° C.) of 20 to 100.
[0018] While vulcanization systems of fluorinated rubber are roughly classified into a polyol vulcanization system and peroxide vulcanization system, any of the systems may be selected.
[0019] Since a magnetic powder is blended to the rubber composition for the magnetic encoder of the present invention in a proportion of 230 to 1900 parts by weight relative to 100 parts by weight of the fluorinated rubber, it has excellent magnetic characteristics with a high residual magnetic flux density.
[0020] It is further preferable to blend the magnetic powder in the proportion of 400 to 1000 parts by weight relative to 100 parts by weight of the fluorinated rubber in order to allow the rubber composition to have more excellent processability as well as more excellent magnetic characteristics.
[0021] Ferrite magnet powders with a particle diameter of about 0.5 to 100 μm or rare earth magnet powders with a particle diameter of about 0.5 to 100 μm may be used as the magnetic powder used in the rubber composition of the magnetic encoder of the present invention. The particle diameter of these magnetic powders may be further reduced by re-pulverization before subjecting the powder to kneading, or the surface of the powder may be treated with a silane coupling agent, titanate coupling agent, higher fatty acid or other conventionally used surface treatment agents for enhancing compatibility with the rubber.
[0022] The rare earth magnet powder is desirably used as the magnetic powder from the view point of magnetic force. Using the rare earth magnet powder as the magnetic powder permits the residual magnetic flux density to be higher and a rubber composition for the magnetic encoder having more excellent magnetic characteristics to be provided.
[0023] When the rare earth magnet powder is used as the magnetic powder as the before described, magnet powder including at least neodymium-iron-boron magnet powder may be used. That is to say, the rare earth magnet powder including a neodymium-iron-boron magnet powder and the other rare earth magnet powder, or a rare earth magnet powder including only the neodymium-iron-boron magnet powder may be used as the before described rare earth magnet powder.
[0024] Also, when the rare earth magnet powder is used as the magnetic powder as the before described, magnet powder including at least samarium-iron-nitrogen magnet powder may be used. That is to say, the rare earth magnet powder including a samarium-iron-nitrogen magnet powder and the other rare earth magnet power, or a rare earth magnet powder including only the samarium-iron-nitrogen magnet powder may be used as the before described rare earth magnet powder.
[0025] A magnet powder including at least the neodymium-iron-boron magnet powder or a magnet powder including at least the samarium-iron-nitrogen magnet powder can be used as a rare earth magnet powder because these magnetic powders are excellent in the production cost and processability.
[0026] Since the samarium-iron-nitrogen magnet powder is excellent in corrosion resistance and has smaller temperature changes of magnetic characteristics as compared with the neodymium-iron-boron magnet powder, the former is particularly suitable to be used as the rare earth magnet powder.
[0027] The neodymium-iron-boron magnet powder and samarium-iron-nitrogen magnet powder include an anisotropic magnet powder exhibiting magnetic anisotropy, and an isotropic magnet powder exhibiting no magnetic anisotropy. While any one of the magnetic powders may be selected as the rubber composition for the magnetic encoder of the invention, selecting the isotropic magnet powder is preferable because it is advantageous with respect to magnetization.
[0028] In the before described rubber compositions for the magnetic encoder of the present invention, it is preferable that the residual magnetic flux density is 300 mT or more.
[0029] The rubber composition for the magnetic encoder having a residual magnetic flux density of 300 mT or more is advantageous for exhibiting high magnetic characteristics.
[0030] The before described rubber compositions for the magnetic encoder of the invention may include, in addition to the above described components, that is to say, in addition to the essential component comprising fluorinated rubber with a Mooney viscosity (ML1+10, 121° C.) of 20 to 100 and a magnetic powder, other additives such as a reinforcing agent represented by silica and carbon black, a coupling agent, an anti-aging agent, a plasticizer, a processing assistant, a cross-linking assistant, an acid receptor and a cross-linking accelerating agent, may be added if necessary as it is used in this art.
[0031] In the before described rubber compositions for the magnetic encoder of the present invention, the magnetic powder and the fluorinated rubber are used as the essential components as the before described. And while the magnetic powder is blended in a proportion of 230 to 1900 parts by weight, more preferably in a proportion of 400 to 1000 parts by weight, relative to 100 parts by weight of the fluorinated rubber in the rubber composition for the magnetic encoder of the present invention, the rubber composition for the magnetic encoder of the present invention may be obtained by appropriately adding the other components used in the art to the essential components as described above.
[0032] Accordingly, in the before described rubber compositions for the magnetic encoder of the present invention, the magnetic powder is desirably blended to the rubber composition for the magnetic encoder of the present invention in a proportion of 70 to 95% percent by weight. If a proportion of the magnetic powder is less than 70% percent by weight in the rubber composition for the magnetic encoder, the residual magnetic flux density, or the magnetic force as the magnetic encoder becomes poor even when the magnetic powder is blended in a proportion of 230 to 1900 parts by weight, more preferably in a proportion of 400 to 1000 parts by weight, relative to 100 parts by weight of the fluorinated rubber. Also, if a proportion of the magnetic powder is larger than 95% percent by weight in the rubber composition for the magnetic encoder, on the other hand, the processability such as kneading and molding becomes extremely poor and flexibility of the vulcanization product is impaired.
[0033] So that, in the before described rubber compositions for the magnetic encoder of the present invention, the magnetic powder is desirably blended to the rubber composition for the magnetic encoder of the present invention in a proportion of 70 to 95% percent by weight.
[0034] The rubber composition for the magnetic encoder of the present invention can be obtained by kneading the components as described above using, for example, a hermetic kneader and an open roll.
[0035] The magnetic encoder proposed in the invention for solving the problems as described above is produced from the before described essential component comprising fluorinated rubber with a Mooney viscosity (ML1+10, 121° C.) of 20 to 100 and a magnetic powder, and the before described other additives using in this art by molding and vulcanization.
[0036] For example, the vulcanization and molding process includes the steps of kneading the components of the rubber composition for the magnetic encoder of the present invention using a hermetic kneader and an open roll, and forming cross-links by injection molding, compression molding or transfer molding of the kneaded product at about 150 to 250° C. for about 0.2 to 60 minutes. The residual magnetic flux density may be further enhanced by forming the cross-links in a magnetic field. A molded product that has been cross-linked may be cross-linked again by treating at about 150 to 250° C. for about 0.5 to 72 hours.
[0037] A metal plate such as a stainless steel plate and cold roll steel plate may be used, if necessary, as a supporting ring of the magnetic encoder at the time of vulcanization and molding. Since the magnetic encoder is bonded by cross-linking, an adhesive such as a commercially available phenol resin, epoxy resin or silane resin is preferably coated on the bonding surface of the metal plate in advance.
[0038] As hitherto described, the rubber composition for the magnetic encoder of the invention is excellent in durability such as heat resistance, oil resistance and chemical resistance with high magnetic characteristics and good processability. Accordingly, the vulcanized and molded magnetic encoder of the invention is also excellent in durability such as heat resistance, oil resistance and chemical resistance with high magnetic characteristics and good processability.
[0039] Consequently, the magnetic encoder of the invention is suitable for use in the rotation speed sensor.
[0040] As described in detail above, the invention provides a rubber composition for a magnetic encoder and the magnetic encoder being excellent in durability such as heat resistance, oil resistance and chemical resistance while the composition has high magnetic characteristics and good processability.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIG. 1 is a partially cut and partially omitted perspective view of the magnetic encoder of the invention bonded to a supporting ring by vulcanization and molding;
[0042] FIG. 2 is a partially omitted cross-sectional view of the magnetic encoder of the invention, wherein the magnetic encoder bonded to the supporting ring shown in FIG. 1 by vulcanizing and molding composes a hermetic device having the encoder in combination with an annular seal element; and
[0043] FIG. 3 is a partially omitted cross-sectional view illustrating a state in which the magnetic encoder of the invention is used as a rotation speed sensor by combining the hermetic device having the encoder shown in FIG. 2 with a rotation detecting sensor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] Rubber compositions for a magnetic encoder of the invention in Examples 1 to 5, and rubber compositions for a magnetic encoder in Comparative Examples 1 to 3 were evaluated as follows. The compositions, production methods and evaluation methods in Examples 1 to 5 and Comparative Examples 1 to 3 are shown below.
Example 1
[0045] Fluorinated rubber (trade name; elastomer E430, manufactured by Dupont Dow Co., Mooney viscosity (M1+10, 121° C.)=31):100 parts by weight
[0046] Neodymium-iron-boron magnet powder (trade name; MQP-B, manufactured by MQI Co.):500 parts by weight
[0047] Higher fatty acid ester (trade name; Glec G8205, manufactured by Kao Corporation):2 parts by weight
[0048] Plasticizer (trade name; RS700, manufactured by Asahi Denka Ltd.):5 parts by weight
[0049] Vulcanization assistant (trade name; Rhenofit CF, manufactured by Rhein Chemie):6 parts by weight
[0050] Acid receptor (trade name; Kyowa Mag, manufactured by Kyowa Chemical Industry Co., Ltd.):2 parts by weight
[0051] The components above were kneaded using a hermetic kneader and an open roll, and the kneaded product was compression-molded at 170° C. for 5 minutes followed by cross linking again at 230° C. for 24 hours to obtain a cross-linked sheet with a thickness of 2 mm.
[0052] The vulcanized sheet was measured with respect to the following items:
[0053] ordinary state property: according to JIS K6251 and 6253;
[0054] air heating aging test: according to JIS K6257 (150° C.×70 hr);
[0055] oil immersion test: according to JIS K6256 (IRM 903 oil, 150° C.×70 hr); and
[0056] magnetic characteristics test: residual magnetic flux density measured with a direct current magnetization meter (manufactured by Metron Inc.).
Example 2
[0057] The cross-linked sheet was produced by the same method as in Example 1, except that 800 parts by weight of the magnet powder was used in place of using 500 parts by weight of the magnetic powder, and the sheet was measured as described above.
Example 3
[0058] The cross-linked sheet was produced by the same method as in Example 1, except that the same quantity of HSB-PA (trade name, samarium-iron-nitrogen magnet powder manufactured by Neomax Co., Ltd.) was used in place of the neodymium-iron-boron magnetic powder (trade name MQP-B, manufactured by MQI Co.) used in Example 1, and the sheet was measured as described above
Example 4
[0059] The cross-linked sheet was produced by the same method as in Example 1, except that the same quantity of DAI-EL G-716 (trade name, manufactured by Daikin Industries, Ltd.; (ML1+10, 121° C.)=45) was used as the fluorinated rubber, and the sheet was measured as described above
Example 5
[0060] Fluorinated rubber (trade name; elastomer product E430, manufactured by Dupont-Dow Co, Mooney viscosity (ML1+10, 121° C.)=31): 100 parts by weight
[0061] Strontium ferrite powder (trade name; FS-317, manufactured by Toda Kogyo Corp.):500 parts by weight
[0062] Higher fatty acid ester (trade name; Glec G8205, manufactured by Kao Corporation):2 parts by weight
[0063] Plasticizer (trade name; RS700, manufactured by Asahi Denka Co., Ltd.):5 parts by weight
[0064] Vulcanization assistant (trade name; Rhenofit CF, manufactured by Rhein Chemie):6 parts by weight
[0065] Acid receptor (trade name; Kyoawa Mag 150, manufactured by Kyowa Chemical Industry Co., Ltd.):2 parts by weight
[0066] A cross-linked sheet was produced using the components above in the same manner as in Example 1, and the sheet was measured as described above.
Comparative Example 1
[0067] The cross-linked sheet was produced by the same method as in Example 1, except that FOR-423 (trade name, manufactured by Ausimont Co.; Mooney viscosity (KL1+10, 121° C.)=16) was used as the fluorinated rubber, and the sheet was measured as described above.
Comparative Example 2
[0068] The cross-linked sheet was produced by the same method as in Example 5, except that 500 parts by weight of the strontium ferrite powder used in Example 5 was changed to 250 parts by weight of the strontium ferrite powder, and the sheet was measured as described above. The weight proportion of the magnetic power in the magnetic rubber composition was 68%.
Comparative Example 3
[0069] Nitrile rubber (trade name; N220SH, manufactured by JSR Corporation): 100 parts by weight
[0070] Strontium ferrite powder (trade name; FS-317, manufactured by Toda Kogyo Corp.):700 parts by weight
[0071] Stearic acid:2 parts by weight
[0072] Anti-aging agent (trade name; Noclac CD):2 parts by weight
[0073] Plasticizer (trade name; RS700, manufactured by Asahi Denka Co., Ltd.):5 parts by weight
[0074] Activated zinc oxide:5 parts by weight
[0075] Sulfur:1 part by weight
[0076] Vulcanization accelerating agent (trade name; Nocseller CZ, manufactured by Ouchi Shinko Chemical Industrial Co., Ltd.):2 parts by weight
[0077] Vulcanization accelerating agent (trade name; Nocseller TT, manufactured by Ouchi Shinko Chemical Industrial Co., Ltd.):2 parts by weight
[0078] Vulcanization assistant (trade name; Rhenofit CT, manufactured by Rhein Chemie):6 parts by weight
[0079] Acid accepting agent (trade name; Kyowa Mag, Manufactured by Kyowa Chemical Industry Co., Ltd.):2 parts by weight
[0080] The components above were kneaded as in Example 1, and the kneaded product was compression-molded at 180° C. for 5 minutes to obtain a cross-linked sheet with a thickness of 2 mm. The sheet was measured as described above.
[0081] The results of evaluation in Examples and Comparative Examples are shown in Table 1 below.
[0000]
TABLE 1
Example
Comparative Example
1
2
3
4
5
1
2
3
Ordinary State
Hardness (pts, D)
45
58
46
46
65
42
32
48
Property
Tensile Strength (MPa)
5.1
6.9
5.9
5.6
8.2
4.6
3.1
4.4
Elongation (%)
38
19
36
35
28
16
160
18
Air Heating Aging
Rate of Change of
±0
+1
±0
±0
+1
±0
+4
+21
Test
Hardness (pts)
Rate of Change of Tensile
+10
+9
+8
+9
+33
+6
+28
−19
Strength (%)
Rate of Change of
−7
−5
−4
−6
−11
−4
−14
−88
Elongation (%)
Oil Resistance
Rate of Change of
−3
−2
−3
−3
−4
−4
−6
+17
Test
Hardness (pts)
(IRM 903)
Rate of Change of Tensile
+10
+9
+9
+7
+11
+3
+4
−46
Strength (%)
Rate of Change of
+10
+6
+3
+1
+3
±0
−13
−76
Elongation (%)
Rate of Volumetric
+0.3
−0.1
+0.4
+0.2
−0.5
+0.3
+0.8
+2.3
Change
Magnetic
Residual Magnetic Flux
340
460
340
340
220
340
120
210
Characteristics
Density (mT)
Contamination of Die
No
No
No
No
No
Yes
No
No
[0082] The samples in Examples 1 to 4 had small rates of change in the air heating aging test and oil resistance test without any contamination and with good processability.
[0083] The sample in Example 5 using the strontium ferrite as the magnetic powder was inferior to the samples in Examples 1 to 4 in which the rare earth magnet powder was used as the magnetic powder with respect to magnetic characteristics.
[0084] The sample in Comparative Example 1 in which a fluorinated rubber having a low Mooney viscosity was not satisfactory with respect to contamination of the die.
[0085] The sample in Comparative Example 2, in which the proportion of blending of the magnetic powder in the rubber composition was as low as 68% relative to the sample in Example 5, had particularly low magnetic characteristics.
[0086] The rate of change of elongation in the air heating aging test was large in the sample in Comparative Example 3 using nitrile rubber, and heat resistance was poor.
Example 6
[0087] The magnetic encoder of the invention was produced as follows by vulcanizing and molding the rubber composition for the magnetic encoder of the invention prepared in Example 1.
[0088] The rubber composition for the magnetic encoder of the invention prepared in Example 1, and a supporting ring 21 made of a stainless steel plate and having an approximately L-shaped cross section were placed in a mold, and an annular molded rubber was bonded to an annular part 21 a of the supporting ring 21 by vulcanization molding. Then, the annular molded rubber was magnetized so that N-poles and S-poles are alternately distributed in the direction of the circumference of the molded rubber, and the magnetic encoder having a magnetic ring 1 attached to a reinforcing ring 21 was obtained.
[0089] It is also possible to obtain the magnetic encoder of the invention by vulcanizing and molding the rubber composition for the magnetic encoder of the invention prepared in Example 1 into an annular shape, and by magnetizing the molded rubber so that N-poles and S-poles are alternately distributed in the direction of the circumference of the molded rubber. The magnetic encoder thus obtained may be used by bonding it to the annular part 21 a of the metallic supporting ring 21 having an approximately L-shape using an adhesive.
[0090] An example in which the magnetic encoder of the invention is used for the rotation speed sensor will be described below.
[0091] The magnetic encoder prepared as described above was assembled with a seal element 8 in which a lip part 6 including an elastic material such as a synthetic rubber was supported on the metallic reinforcing ring 3 having an approximately L-shape as shown in FIG. 2 . The magnetic encoder was disposed on a rotating member such as a bearing shaft as a hermetic device having the encoder as shown in FIG. 3 . A rotation detection sensor 7 is disposed in the vicinity of the magnetic encoder so as to be opposed to the surface of the magnetic encoder including the magnetic ring 1 as shown in FIG. 3 . In the illustrated embodiment, the magnetic encoder including the magnetic ring 1 rotated together with the rotation of the rotating member of the bearing shaft, and the rotation speed is detected by sensing the pulses generated from the magnetic ring 1 with the rotation detection sensor 7 .
[0092] Since the magnetic encoder of the invention has a high residual magnetic flux density, the distance between the rotation detection sensor 7 and the magnetic encoder including the magnetic ring 1 , or the distance represented in the horizontal direction in FIG. 3 , may be increased. Since tolerance of assembly for assembling the system can be increased by this large distance, freedom of design is increased to make it advantageous to apply the magnetic encoder to various uses. | The invention provides a rubber composition for a magnetic encoder being excellent in durability such as heat resistance, oil resistance and chemical resistance, having high magnetic characteristics and being excellent in processability and a magnetic encoder using the rubber composition. The magnetic rubber composition for the magnetic encoder includes a fluorinated rubber with a Mooney viscosity (ML1+10, 121° C.) of 20 to 100 and a magnetic powder, and the magnetic powder is blended in a proportion of 230 to 1900 parts by weight relative to 100 parts by weight of the fluorinated rubber. The magnetic encoder is provided by vulcanizing and molding the rubber composition. | 5 |
BACKGROUND OF THE INVENTION
It is well known that various clearer devices are provided for draft rolls in spinning machines. Those clearer devices can be classified into the top clearer device which is disposed above a draft roll section and the bottom clearer device which is disposed below the draft roll section. The former is generally placed against a set of top rolls and the latter against a set of bottom rolls. It is conventional to provide the top and bottom clearer devices of a same or different configuration, whereas only one of the clearer devices is provided as occasion may require.
Those clearer devices use a clearer member of suitable material which may easily pick off lint and fly carried by the draft rolls, for example, felt, furry cloth, a brush sheet, artificial leather and rubber. There are two types of the clearer devices: the rotary roll type wherein such a clearer member is affixed to a surface of a moving component and kept in contact with the draft rolls and the stationary type wherein the clearer member is secured on a surface of a fixed or stationary component while being in contact with the draft rolls. The former is more useful in long-term, continued operation but less satisfactory as far as clearing performance is concerned. The latter is required to very often remove the fly and failure to do so results in the possibility that the fly accumulated thereon can enter final products. Therefore, a pneumatic clearer has recently been developed and widely used. The mere use of incoming air is however unsatisfactory in removing the accumulated fly and sometimes needs the assistance of brush rolls or the rotary roll type or stationary type clearer. It is general practice to form flutes in the bottom rolls, that is, the draft rolls but the fly or foreign objects enter into the flutes. Accordingly, no complete removal of the fly is assured by only the incoming air.
In order to make use of the advantages of both the rotary type clearer and the stationary type clearer, an apron type of clearer has recently been used which includes the clearer member of an apron shape traveling in contact with the surface of the draft rolls and wiping off the fly at its nonoperative section. The apron type of clearers can be similarly classified into the top apron clearers and the bottom apron clearers. The top and bottom clearers are both installed or one of the both clearers is installed together with the other types of clearers as discussed above.
Of the above clearers, the bottom apron clearer device is needed to be placed below the draft rolls and thus in a limited space so that is should be simple in construction, easy to manipulate and ensure stable and satisfactory clearing performances. Specifically, for the bottom apron clearer it is greatly possible that the fly can enter inside the apron. In particular, within a spinning chamber with an air blower, the fly blown off by air tends to enter inside the bottom and top aprons. It is, therefore, necessary for the apron clearer to remove the fly adhering to not only the outer surface but also the inner surface of the clearer.
SUMMARY OF THE INVENTION
Bearing in mind the foregoing, it is an object of the present invention to provide a clearer device which fulfills all the requirements discussed above.
More particularly, the present invention aims to device a clearer which completely clears a number of draft rolls.
It is another object of the present invention to provide a clearer device for draft rolls which completely removes the lint and fly accumulated on an apron and withstands long-term and continued operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a clearer device constructed in accordance with the present invention;
FIG. 2 is a view for explanation of operation of the device of FIG. 1;
FIG. 3 is a plan view of the clearer device of FIG. 1 with a series of draft rolls omitted and part of an apron broken;
FIG. 4 is an exploded perspective view showing structure of the clearer device exclusive of the apron;
FIG. 5 is an enlarged view showing part of the device of FIG. 4 together with part of the apron;
FIG. 6 is a plan view of FIG. 5;
FIG. 7 is a cross sectional view on the line VII--VII, FIG. 6;
FIG. 8 is a fragmentary front view of an apron roll with the apron shown in section; and
FIG. 9 is an exploded perspective view of part of the structure shown in FIG. 8.
Whereas a typical bottom clearer device is shown as being provided for four draft rolls, it is equally applicable to a given number of pairs of the draft rolls. Though those draft rolls are aligned substantially in a horizontal plane in typical embodiments, they may be aligned with a proper inclination. The present clearer device is further applicable to a top apron.
DETAILED DESCRIPTION OF THE INVENTION
A bottom clearer device is generally designated at 1 and so built on a frame assembly 6 as to be rotatable about a pivot 5. The frame assembly 6 is secured on an inclinable stand 7 in front of the frame assembly so that an apron can be held on in contact with draft rolls.
The pivot shaft 5 is freely secured on a roll stand (not shown) carrying the draft rolls and located lengthwise of a machine platform and in parallel with a series of the draft rolls. The shaft 5 is reciprocated by a link lever 11 connecting an arm 12 affixed to opposite ends or intermediate portions of the shaft 5 and a second arm 10 affixed to a reciprocating shaft 9. Although in the drawings the arm 12 affixed to the shaft 5 is of an "L" shape with capability of further actuating a transverse lever of a combing device 8 to be discussed later, these drive mechanisms may be separate. Moreover, while the illustrated example comprises the "L" shaped lever 12 connecting the rotary shaft 9 and the shaft 5, it is possible to use only the shaft 5. Bottom rolls and top rolls are indicated at 2 and 3 with the former being fluted rolls. An endless apron 4 is made of the above-mentioned clearer member and supported by the frame assembly 6. The apron 4 rotates in the direction of arrow as the shaft 5 transmits only force of unidirectional rotation to the apron 4. With the stand 7 being inclined as viewed in FIG. 2, the bottom clearer device 1 is open for easy access in maintaining and clearing the apron 4. Under such a circumstance adjustment can be made on the locations of guide plates 18 described below by use of different roll gauges.
As best shown in FIG. 4, details of structure of the bottom clearer device will be clarified mainly by reference to FIG. 4. The frame assembly 6 has side frames 15,15 with inwardly bent top ends at its both sides, vertical wall sections of the side frames carrying fixing rods 16,16, respectively. On the rear side of the two vertical wall sections, there are cleaved openings 15b,15b which allow passage of the shaft 5 therethrough so that the frame assembly 6 is integrally rotatably supported by the shaft 5. As will be discussed later, an apron driving roll 13 is mounted on the shaft 5 to move the apron 4 stretched thereacross. Folded horizontal sections 15a,15a on the top of the opposite side frames 15,15 are provided with slits 17,17 in which the opposite ends of the guide plates 18,18 are received by means of bolts and nuts. The guide plates 18 are of an "L" shaped profile with curved top end portions and serve to raise and guide the apron 4 to a level to contact the draft rolls 2. Since the height and position of the guide plates 18 depend on the arrangement and outer diameter of the draft rolls 2, the guide plates are of a selected height and received freely within the slits 17,17. Fastening bolts 17a respectively traverse the slits 17 from above the guide plates 18. It is recommended that a nut 17c be provided with a projection 17b of which a portion is fitted within the slit 17 to prevent the nut from rotating itself. On the front side of the side frames 15,15 there is provided an apron guide roll 14 whose pivot 14a is eccentric and has a screwed shaft section passing through holes 14b in the opposite side frames 15,15, and secured with nuts (not shown). The guide roll 14 is fixedly secured and may be located in any desired eccentric position to allow adjustment of tension of the apron 4. The eccentric guide roll 14 may be enclosed by a freely rotatable cylinder so as to minimize resistance to the rotating movement of the apron 4. The stands 7,7 pivoted on front lower sections of the side frames 15,15 are respectively provided with screwed steps 7a of an adjustable height and pivots 7b received within holes 7c so that the stands 7 are inclined somewhat backward as shown in FIG. 1. Slits 22,22 are formed in front lower sections of the vertical walls of the opposite side walls 15,15 to hold a reciprocating lever 20 of a device for picking off the fly carried by the clearer.
As indicated in FIG. 3, the apron 4 is stretched between the guide roll 14 and the apron driving roll 13 within the frame assembly 6 and driven by the latter roll 13.
While the apron driving roll 13 is supported by the shaft 5, the shaft 5 is reciprocated but is operative to move the apron 4 in only one direction. Accordingly, only unidirectional rotation of the reciprocating movement of the shaft 5 is transmitted to the apron driving tool 13.
In other words, the apron driving roll 13 is loosely secured around the shaft 5 through journal members 34,34 on both ends of a metallic tube 35 as shown in FIGS. 8 and 9 and freely rotatable via bushings 32,32. One of the journal members 34,34 is coupled to the shaft 5 via a unidirectional clutch 33 so that as the shaft 5 rotates in a reciprocating fashion, it feeds only rotation in one direction to the journal members 34, rotating the tube 35 affixed to the journal member 34 in one direction at a given interval of time. The journal member 34 has a step section 34b and a flange section 34a, the step section 34b holding the tube 35 and having a hole 34c receiving the unidirectional clutch 33. The peripheral surface of the tube 35 is covered with an antiskid coating 36 of rugged rubber or metal or other materials having friction resistance by means of fitting or adhering. The coating 36 increases the friction resistance of the apron driving roll 13 and smooths movement of the apron 4. It is desirable to take measures for protecting the friction surface of the apron 4, the journal member 34, the side frames 15 and the friction surface of the bushings 32, since the fly and dust can enter thereto. In the illustrated example, a dust cover 37 is provided. The opposite ends of the coating 36 about the tube 35 are located inside the side edges of the journal member 34. A space 36a is formed between the rear side of the apron 4 and the tube 35 or the journal member 34 to accommodate the dust cover 37 having a flange section. The dust cover 37 is of a disc form with the flange portion. To keep the dust cover 37 from rotating, the opposite surface of the flange 39 is provided with an engaging extension 38 whose bottom side 38a engages with the top of the side frame 15. The extension 38 serves also as a guide for the apron 4. Preferably, the dust cover 37 is made of plastic.
While being in contact with the bottom rolls 2 of the draft rolls, the apron 4 travels intermittently in the same or opposite direction to movement of the surfaces of the respective rolls, picking off the fly or dust accumulated on the bottom rolls. The apron 4 is provided with the device for wiping off the fly and making the surfaces of the apron clean and fresh. The wiper device generally combs lightly on the operative surface of the apron while traversing the direction of travel of the apron. However, within the bottom apron clearer device, the fly tends to enter inside the apron 4 and curb movement of the apron. The present invention provides an improvement in such a wiper device which clears the apron 4 more completely and keeps on conveying the fly outwardly from one of the opposite sides while removing the fly from the inner surface of the apron 4.
As indicated in FIG. 4, the wiper device 8 of FIG. 1 comprises an inner comb plate 24 and an outer comb plate 25 sandwiching the moving lower section of the apron 4, both of which lightly contact and traverse the inner and outer surfaces of the apron 4. The opposite ends of the respective comb plates rest on supports 23,23 which are folded top portions of the respective comb levers 20. The comb levers 20 are secured via the arms 12,12a carrying the reciprocating shaft 5 and link rods 19,19 and have inwardly oriented pivots 21,21 at their tip portions. The respective pivots 21 pass through the slits 22 in the vertical wall sections of the side walls 15 while being loosely supported thereby. The supports 23 allow the respective comb plates 24,25 to traverse substantially in parallel with the slits 22. The supports 23 and the comb plates are assembled as depicted in FIGS. 5 through 7. Whereas the outer comb plate 25 abuts against the bottom of the support 23, the inner comb plate 24 falls by gravity and settles on the top of the support 23. This will be more fully understood from a consideration of FIG. 7 wherein the support 23 has an opening for receiving a bolt 27 with its lower side being traversed by the outer comb plate 25 and its upper side by a collar 26 and a washer 28 and a nut 29 is fixed to the outer surface of the outer comb plate 25 via a washer 28a to thereby form a stud. The inner comb plate 24 is provided with an opening in which the collar 26 is freely received and thus freely movable between the support 23 and the washer 28. In the drawings the support 23 is shown having the same thickness as that of the apron 4. When the inner comb plate 24 rests on the plate 23 by gravity, the tooth section of the inner comb plate 24 lightly contacts the upper surface (the inner side section) of the apron 4 so that the support 23 is preferably thinner than the apron 4.
The comb tooth in the comb plates applied to the apron clearer are generally of an equilateral triangle with working tooth at the same angle along its traverse direction. The combing plates of the above shape are satisfactory in wiping off the fly and dust picked from the apron or conveying them to a suction device. However, for the combing plates applied to a limited space inside the apron as taught by the present invention, it is desirable to shift forcedly the fly and dust either leftward or rightward and more preferably as the comb plates traverse. Accordingly, the present invention provides an improved combing device which also conveys the fly and dust outwardly in a lateral direction. In other words, as viewed from FIG. 6, the tooth section 30 of the inner comb plate 24 of the combing device 8 consists of straight single-edge sections substantially normal to the traverse direction and working edge sections inclined with respect to the traverse direction, the latter conveying continuously the fly in the direction of a component of force exerted on the inclined surfaces of the working edge sections. When the apron 4 runs in the direction of the arrow A and the comb plates 24,25 traverse in the direction of the arrow B as shown in FIG. 5, the fly 40 is wound in a spiral fashion and conveyed rightward each traversing operation because of the tooth section 30 of the inner comb plate 24 of the shape shown in FIG. 6. If the tooth section 30 of the comb plate 24 is adapted such that each teeth inclines both leftward and rightward along its length, then the fly 40 is distributed in the both directions. The result is that the inner surface of the apron 4 becomes cleared and fresh and the apron travels without slipping even due to accumulation of the fly and dust.
The clearer device according to the present invention offers the following advantages:
(1) it is easy to manipulate;
(2) the draft rolls are always cleared and kept fresh;
(3) the apron is driven steadily and stably;
(4) for the reasons as set forth above manifold spinning machines with the device of the present invention produce high quality products. | This invention relates to a clearer device for use in clearing draft rolls of a spinning machine, and more particularly to a clearer device which is disposed below a series of juxtaposed draft rolls and includes an endless clearer member (hereinafter called an "apron") travelling operatively in contact with the peripheral surfaces of the draft rolls for clearing the draft rolls. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation and claims the priority benefit of U.S. patent application Ser. No. 14/323,884, filed on Jul. 3, 2014; which in turn is a continuation of U.S. patent application Ser. No. 14/061,720, filed on Oct. 23, 2013, issued on Aug. 19, 2014, as U.S. Pat. No. 8,813,180; which in turn is a continuation of U.S. patent application Ser. No. 13/650,179, filed on Oct. 12, 2012, issued on Nov. 26, 2013, as U.S. Pat. No. 8,595,791; which in turn is a continuation of U.S. patent application Ser. No. 12/788,339, filed on May 27, 2010, issued on Nov. 13, 2012 as U.S. Pat. No. 8,312,507; which in turn is a continuation-in-part of U.S. patent application Ser. No. 12/771,491, filed on Apr. 30, 2010, issued on Jul. 12, 2011, as U.S. Pat. No. 7,979,585; which in turn is a continuation of U.S. patent application Ser. No. 11/582,613, filed on Oct. 17, 2006, issued on May 11, 2010, as U.S. Pat. No. 7,716,378. The disclosures of each of the above referenced applications are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field
[0003] This invention relates generally to data networking, and more specifically, to a system and method to apply a network traffic policy based on a user identity during an application session.
[0004] 2. Related Art
[0005] The secure data network of a company is a critical component for day-to-day functioning of company business activities. Company employees access the secure data network for communication within the company and with the outside world. Company information, oftentimes proprietary or confidential, is exchanged during the communication.
[0006] Typically, an employee gains access to the company's secure data network by means of a network logon procedure using a private user identity, such as a user name “Robert P. Williamson” or an employee number “NG01-60410”. Subsequent information exchange using the company's office applications, such as email, file transfer or document control is traceable based on the private user identity through network event logs.
[0007] Since the late 1990's, we have been witnessing the phenomenal rising popularity of public communication applications and services, such as email and Instant Messaging offered by Yahoo™, America Online™ (AOL), or Google™, conferencing and collaboration services offered by WebEx™ or Centra™, or peer-to-peer services for a variety of file sharing. Generally, a public communication service allows a user to exchange information through messaging, text chat or document exchange using a public user identity, such as “butterdragon”, “fingemai11984”, or “peterrabbit”.
[0008] However, in a company setting, when an employee connects to a public communication service with a public user identity over the company's secure data network, the information exchange is not easily traceable if at all since the public user identity is not tied to the private user identity.
[0009] In one example, a company's information technology (IT) department notices that an employee Victor has been using the company's email system to send out proprietary documents, violating the company's security policy.
[0010] After issuing a warning to Victor, the IT department finds no further violations. Unfortunately, they are not aware of the fact that Victor has continued this activity using Yahoo™ email with a public user identity “PiratesOfCaribbean@Yahoo.com”.
[0011] In another example, two weeks before a major trade show, a company implements a security measure to monitor communication activities of employees of director level and above to ensure confidentiality of competitive information. This security measure, covering company email, phone conversation and voice messaging, nevertheless proves to be a failure as sensitive information leaks out to a business reporter anyway prior to the trade show. The source of the leak may never be confirmed, but the business reporter privately discloses that he gets the information from an anonymous employee of the company using AOL Instant Messaging™ with screen name “opensecret2006”.
[0012] The above discussion illustrates the need for a security solution to associate a user identity to a public application.
BRIEF SUMMARY OF THE INVENTION
[0013] Method for applying a security policy to an application session, includes: recognizing the application session between a network and an application via a security gateway; determining by the security gateway a user identity of the application session using information about the application session; obtaining by the security gateway the security policy comprising network parameters mapped to the user identity; and applying the security policy to the application session by the security gateway. The user identity may be a network user identity or an application user identity recognized from packets of the application session. The security policy may comprise a network traffic policy mapped and/or a document access policy mapped to the user identity, where the network traffic policy is applied to the application session. The security gateway may further generate a security report concerning the application of the security policy to the application session.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1A illustrates a secure network.
[0015] FIG. 1B illustrates an access session and an application session.
[0016] FIG. 1C illustrates an access session record and an application session record.
[0017] FIG. 2 illustrates a process to generate an application session record.
[0018] FIG. 3 illustrates a process to recognize an application session.
[0019] FIG. 4A illustrates a process to determine a public user identity of application session.
[0020] FIG. 4B illustrates a data packet in an AIM log-on packet.
[0021] FIG. 5 illustrates a process to determine a private user identity.
[0022] FIG. 6 illustrates an embodiment of a security gateway obtaining a security policy by querying a corporate directory.
[0023] FIG. 7 illustrates a security policy including a security control.
[0024] FIG. 8 illustrates a plurality of embodiments of network traffic policy.
DETAILED DESCRIPTION OF THE INVENTION
[0025] FIG. 1A illustrates a secure network.
[0026] A secure network 160 includes a host 130 . User 120 uses host 130 to access a public application 180 hosted in application server 190 . Application server 190 is outside of secure network 160 . The network traffic between host 130 and application server 190 passes through security gateway 150 . The security gateway 150 is operationally coupled to a processor 171 and a computer readable medium 172 . The computer readable medium 172 stores computer readable program code for implementing the various embodiments of the present invention as described herein.
[0027] Host 130 is a computing device with network access capabilities. The host 130 is operationally coupled to a processor 173 and a computer readable medium 174 . The computer readable medium 174 stores computer readable program code for implementing the various embodiments of the present invention as described herein. In some embodiments, host 130 is a workstation, a desktop personal computer or a laptop personal computer. In some embodiments, host 130 is a Personal Data Assistant (PDA), a smartphone, or a cellular phone.
[0028] In some embodiments, secure network 160 is an Internet Protocol (IP) network. In some embodiments, secure network 160 is a corporate data network or a regional corporate data network. In some embodiments, secure network 160 is an Internet service provider network. In some embodiments, secure network 160 is a residential data network. In some embodiments, secure network 160 includes a wired network such as Ethernet. In some embodiments, secure network 160 includes a wireless network such as a WiFi network.
[0029] Public application 180 provides a service that allows user 120 to communicate with other users in a real-time fashion. In some embodiments, the service includes text chat. In some embodiments, the service includes a voice call or a video call. In some embodiments, the service includes a network game. In some embodiments, the service includes exchanging a document, such as sending or receiving a text document, a PowerPoint™ presentation, an Excel™ spreadsheet, an image file, a music file or a video clip. In some embodiments, the service includes a collaborative document processing such as creating a document, a business plan, an agreement, wherein user 120 collaborates with other users in a real time fashion. In some embodiments, the service includes a collaborative information exchange such as a conference call. In some embodiments, the service is a social networking service. In some embodiments, the service includes real-time collaboration and non real-time collaboration.
[0030] In one example, public application 180 provides America Online Instant Messenger™ service. In one example, public application 180 provides Yahoo Instant Messenger™ voice service. In some embodiments, public application 180 provides a file sharing service such as Kazaa™ file sharing service. In some embodiments, public application 180 provides a network game service such as Microsoft™ Network Game service. In some embodiments, public application 180 provides an on-line collaborative document processing such as Google Docs™, and Salesforce.com™. In some embodiments, public application 180 provides an on-line information exchange and communications such as WebEx™. In some embodiments, public application 180 provides live information streaming such as live video streaming, live audio streaming, and instantaneous picture uploading.
[0031] Security gateway 150 is situated at the edge of secure network 160 . Security gateway 150 connects secure network 160 to public application 180 . Security gateway 150 receives network traffic from secure network 160 and transmits the network traffic to application server 190 . Likewise, security gateway 150 receives network traffic from application server 190 and transmits the network traffic to secure network 160 .
[0032] In some embodiments, security gateway 150 includes the function of a corporate Wide Area Network (WAN) gateway. In some embodiments, security gateway 150 includes the function of a residential broadband gateway. In some embodiments, security gateway 150 includes the function of a WAN gateway for an Internet service provider.
[0033] FIG. 1B illustrates an access session and an application session.
[0034] User 120 uses host 130 to access secure network 160 during an access session 162 .
[0035] Host 130 has a host identity 134 . Host 130 uses host identity 134 to connect to secure network 160 . In some embodiments, host identity 134 includes an IP address. In some embodiments, host identity 134 includes a Media Access Control (MAC) address.
[0036] Within secure network 160 , user 120 has a private user identity 124 . In some embodiments, private user identity 124 is an employee number or an employee name. In some embodiments, private user identity 124 is an Internet service subscription identity. In some embodiments, access session 162 is established after a successful network user log-in procedure, such as an employee network log-in, for secure network 160 using private user identity 124 . Private user identity 124 is associated with host identity 134 . In some embodiments, host 130 is a guest computing device. Private user identity 124 is associated with an Ethernet switch port where host 130 connects. In this embodiment, private user identity 124 is a port number, an Ethernet interface identity, or an Ethernet VLAN identity.
[0037] User 120 uses host 130 to access public application 180 in an application session 182 . User 120 uses a public user identity 127 during application session 182 . In some embodiments, public application 180 prompts user 120 to log-in before establishing application session 182 . During the application user log-in procedure, user 120 provides to public application 180 public user identity 127 . In another embodiment, public application 180 selects a public user identity 127 for user 120 for application session 182 . In some embodiments, public user identity 127 is set up through a user registration process or a service subscription process. Network traffic in application session 182 passes through security gateway 150 .
[0038] FIG. 1C illustrates an access session record and an application session record.
[0039] Access session record 164 records information about access session 162 . The information includes private user identity 124 , host identity 134 and access session time 166 . In some embodiments, access session time 166 is the starting time when access session 162 is established. In some embodiments, access session time 166 includes the starting time and the ending time when user 120 finishes access session 162 . In some embodiments, access session time 166 is a time stamp for a time during access session 162 .
[0040] Application session record 184 records information about application session 182 . The information includes private user identity 124 , public user identity 127 , and application session time 186 . In some embodiments, the information further includes host identity 134 . In some embodiments, application session time 186 includes the starting time when application session 182 is established. In some embodiments, application session time 186 includes a time stamp during application session 182 . In some embodiments, application session time 186 includes a time stamp when security gateway 150 recognizes application session 182 .
[0041] FIG. 2 illustrates a process to generate an application session record.
[0042] The process of generating application session record 184 includes multiple steps.
[0043] In step 201 , security gateway 150 recognizes an application session.
[0044] In step 202 , security gateway 150 determines a public user identity of the application session.
[0045] In step 203 , security gateway 150 determines a private user identity using information about the application session.
[0046] FIGS. 3-5 illustrates steps 201 - 203 respectively.
[0047] FIG. 3 illustrates a process to recognize an application session.
[0048] Security gateway 150 inspects network traffic between host 130 and application server 190 to recognize application session 182 for public application 180 .
[0049] In some embodiments, security gateway 150 inspects data packet 339 between host 130 and application server 190 for the recognition of application session 182 .
[0050] Security gateway 150 includes an application identifier 355 for public application 180 . Application identifier 355 includes information for recognizing application session 182 . In some embodiments, application identifier 355 includes a transport layer information, such as Transmission Control Protocol (TCP) or User Diagram Protocol (UDP); and at least one transport port number, such as a TCP port number or a UDP port number. In some embodiments, application identifier 355 includes application layer information, such as one or more data filters wherein a data filter specifies a value and a position of the value in a data packet. In one example, a data filter is [byte 0 with value “0x52”]. In one example, a data filter is [byte 4 - 7 with ASCII value of “ADEH”].
[0051] Security gateway 150 matches data packet 339 against application identifier 355 .
[0052] In some embodiments, application identifier 355 includes transport protocol type of TCP and a destination TCP port number of 5190 , the TCP port number used by AIM protocol. In this embodiment, data packet 339 is a TCP packet from host 130 to application server 190 . Security gateway 150 matches data packet 339 against application identifier 355 and determines that public application 180 provides AIM service.
[0053] Security gateway 150 creates application session record 184 . Security gateway 150 extracts the source IP address from the IP header of data packet 339 , and stores the source IP address as host identity 134 . In some embodiments, data packet 339 includes link layer information, such as a source MAC address; security gateway 150 extracts and stores the source MAC address as host identity 134 .
[0054] In some embodiments, security gateway 150 connects to a clock 359 . Clock 359 indicates the current time of day. Security gateway 150 stores the time of day indicated by clock 359 in application session time 186 .
[0055] FIG. 4A illustrates a process to determine a public user identity of application session 182 .
[0056] The method for determining public user identity 127 is typically specific to public application 180 . In some embodiments, data packet 339 is an application packet. For example, public application 180 provides AIM service; data packet 339 is an AIM packet.
[0057] An AIM packet includes multiple fields, for example
[0058] Command start field is a 1-byte data field starting at byte offset 0 having a fixed hexadecimal value “0x02”; Channel ID field is a 1-byte data field starting at byte offset 1 ; Sequence number field is a 2-byte integer starting at byte offset 2 ; Data field length field is a 2-byte data field starting at byte offset 4 ; Family field is a 2-byte data field starting at byte offset 6 ; and Subtype field is a 2-byte data field starting at byte offset 8 .
[0059] An AIM log-on packet is a AIM packet with family field having a fixed hexadecimal value of “0x00 0x 17 ” and subtype field having a fixed hexadecimal value of “0x00 0x06”.
[0060] AIM log-on packet further includes buddy name length field, a 1-byte integer starting at byte offset 19 , and a variable length buddy name field starting at byte offset 20 . Buddy name length field indicates the length in bytes of buddy name field.
[0061] Security gateway 150 matches data packet 339 to determine if data packet 339 is an AIM log-on packet. In some embodiments, data packet 339 is an AIM log-on packet 400 illustrated in FIG. 4B . Security gateway 150 extracts buddy name length field 405 . Security gateway 150 furthers extracts buddy name field 407 . In this embodiment, buddy name length field 405 is integer “13” and buddy name field 407 is “JohnSmith1984”. Security gateway 150 stores “JohnSmith1984” as public user identity 127 in application session record 184 .
[0062] In some embodiments, data packet 339 is not an AIM log-on packet. Security gateway 150 inspects another data packet from host 130 .
[0063] FIG. 5 illustrates a process to determine a private user identity.
[0064] Secure network 160 includes an identity server 570 . The identity server 570 is operationally coupled to a processor 581 and a computer readable medium 582 . The computer readable medium 582 stores computer readable program code for implementing the various embodiments of the present invention as described herein. Identity server 570 includes access session record 164 of access session 162 during which user 120 accesses application session 182 .
[0065] Security gateway 150 queries identity server 570 . Security gateway 150 sends host identity 134 and application session time 186 to identity server 570 .
[0066] Identity server 570 receives host identity 134 and application session time 186 . Identity server 570 matches host identity 134 and application session time 186 against access session record 164 . Identity server 570 determines that host identity 134 matches host identity of access session record 164 . Identity server 570 further determines that application session time 186 matches access session time 166 of access session record 164 as application session time 186 is between the starting time and the ending time of access session record 164 . Identity server 570 sends private user identity 124 of access session record 164 to security gateway 150 as a response to the query.
[0067] Security gateway 150 receives private user identity 124 from identity server 570 , and stores private user identity 124 in application session record 184 .
[0068] In some embodiments, security gateway 150 stores public user identity 127 in application session record 184 after recognizing a log-on approval indication for the public user identity 127 from public application 180 .
[0069] In some embodiments, security gateway 150 queries identity server 570 immediately after determining public user identity 127 . In some embodiments, security gateway 150 queries identity server 570 after application session 182 ends.
[0070] In some embodiments, security gateway 150 queries identity server 570 by sending a plurality of host identities in a bulk request; and receives a plurality of private user identities in a bulk response.
[0071] In some embodiments, application session record 184 includes additional user information associated with private user identity 124 , such as cubicle or office number, cubicle or office location, telephone number, email address, mail-drop location, department name/identity, or manager name.
[0072] In some embodiments, security gateway 150 obtains the additional user information from identity server 570 . In some embodiments, security gateway 150 obtains the additional user information by querying a different server, such as a corporate directory server, by using the private user identity 124 received from identity server 570 .
[0073] In some embodiments, public application 180 provides file transfer service using File Transfer Protocol (FTP) protocol or a proprietary protocol. In some embodiments, public application 180 provides email service using Simple Mail Transfer Protocol (SMTP), Internet Message Access Protocol (IMAP) or Post Office Protocol version 3 (POP3) protocol.
[0074] By using the application session record, the private user identity 124 and the public user identity 127 for an application session 182 may be determined. In some embodiments as illustrated by FIG. 6 , upon determining the public user identity and the private user identity, security gateway 150 obtains security policy 402 for the application session 182 by querying corporate directory 470 . In an embodiment, corporate directory 470 comprises security policy 402 . In some embodiments, corporate directory 470 is a server computer comprising a storage 601 that includes security policy 402 . In some embodiments, corporate directory 470 is a database comprising security policy 402 . In another embodiment, corporate directory 470 is a software module with program code stored on a computer readable medium (not shown) running in a computer. In some embodiments, corporate directory 470 resides in identity server 570 . In some embodiments, corporate directory 470 uses directory technologies such as Microsoft Active Directory™, lightweight directory access protocol (LDAP) directory services, web services, directory services using Java™ technologies. In some embodiments, corporate directory 470 includes a policy server hosting security policy 402 and other policies.
[0075] Security gateway 150 queries corporate directory 470 for a security policy, where the query includes user identity 424 . User identity 424 may include private user identity 124 or public user identity 127 . Corporate directory 470 matches user identity 424 against security policy 402 and determines security policy 402 is applicable to user identity 424 . In some embodiments security policy 402 maps network parameters to a user identity and there is a match between user identity 424 and the user identity in the security policy 402 . In some embodiments, security policy 402 maps network parameters to a group identity (not shown) and user identity 424 is a member of the group identity. In response to finding the match between the user identity 424 and the user identity in the security policy 402 , corporate directory 470 sends security policy 402 to security gateway 150 .
[0076] In some embodiments, security gateway 150 generates security report 475 based on application session record 184 and security policy 402 . In some embodiments, security gateway 150 generates security report 475 based on a pre-determined user identity or a list of pre-determined user identities. For example, the security report may be generated based on an input of user identity or identities. In some embodiments, security gateway 150 generates security report 475 based on a pre-defined schedule or when requested by an operator.
[0077] In some embodiments, security policy 402 includes a security control function as illustrated in FIG. 7 . Security gateway 150 applies the security policy 402 received from corporate directory 470 in response to the query to application session 182 . Security policy 402 typically are configured by a company to protect against improper access to the company confidential documents and to protect against improper usage of the company secure network 160 vital for the company operation. In some embodiments, in response to receiving the security policy 402 , the security gateway 150 confirms that the received security policy 402 contains a user identity that matches the user identity 424 sent in the query. In response to the confirmation, the security gateway 150 applies the security policy 402 to the application session 182 . In FIG. 7 , security policy 402 includes network traffic policy 451 or document access policy 453 .
[0078] FIG. 8 illustrates a plurality of embodiments of network traffic policy 451 . In some embodiments, network traffic policy 451 specifies network based application session access control indicating if user identity 424 is denied or allowed to continue application session 182 . If denied, security gateway 150 may stop forwarding data packets 439 of application session 182 . In some embodiments, network traffic policy 451 specifies bandwidth rate capacity such as 1 Mbps, 100 MB per day, or 5 GB per month. In an embodiment, bandwidth rate capacity is measured in packets such as 100 packets per second, 10 thousand packets per day or 4 million packets per month. In some embodiments, network traffic policy 451 specifies a quality of service (QOS) mapped to user identity 424 for application session 182 . For example, network traffic policy 451 indicates a change of Differentiated Services Code Point (DSCP) marking in the data packets 439 of application session 182 . In some embodiments, network traffic policy 451 specifies a queuing delay, a queuing priority, a packet forwarding path, a link interface preference, a server load balancing preference, a packet routing policy, or other control to handle data packets 439 of application session 182 .
[0079] In some embodiments, network traffic policy 451 includes a traffic shaping control. In one example, traffic shaping control specifies a TCP profile such as a change of window segment size, or a TCP window adjustment. [ 0078 ] In some embodiments, network traffic policy 451 indicates session connection rate control based on user identity 424 specifying a rate or capacity such as 10 session connections per second, 35 concurrent sessions, 100 sessions during lunch hour, 500 sessions a day, 24 voice sessions a day, or 75 file transfer sessions an hour. In some embodiments, network traffic policy 451 may specify, when exceeding the rate or capacity, if application session 182 is denied or data packets 439 of application session 182 are dropped.
[0080] In some embodiments, network traffic policy 451 includes application session modification control mapped to user identity 424 , specifying how data packets 439 of application session 182 are modified for the user with the user identity 424 . In one example, application session modification control specifies security gateway 150 should perform network address translation (NAT) to application session 182 for user identity 424 . In one example, security gateway 150 should perform port address translation (PAT) to application session 182 using a pre-determined port number for user identity 424 . In another example, security gateway 150 should perform content substitution if application session 182 is an HTTP session and if a Universal Resource Locator (URL) in data packets 439 of application session 182 matches a pre-determined URL for user identity 424 . In an example, security gateway 150 should perform filename substitution if application session 182 is a file transfer session and if a filename matching a pre-determined filename is found in data packets 439 of application session 182 for user identity 424 . In another example, security gateway 150 should insert a cookie for user identity 424 if application session 182 is an HTTP session, with optionally data packets 439 matching a pre-determined POST or GET request of a URL.
[0081] Returning to FIG. 7 , in some embodiments, document access policy 453 specifies if access to document 447 is allowed or denied. In some embodiments, document 447 includes a file, a business agreement, a contract, a spreadsheet, a presentation, a drawing, a textual document, a manual, a program, a piece of software program, a design, a product specification, a datasheet, a video file, an audio file, an email, a voice mail, a fax, a photocopy of a document, or any business document. In some embodiments, document 447 includes a URL leading to digital information such as database query result, a web page, a video, or a piece of music. In some embodiments, document 447 includes real time transfer or streaming of information such as video streaming, audio streaming, a web cast, a podcast, a video show, a teleconference session, or a phone call. In some embodiments, document access policy 453 includes document identity 443 and document user identity 444 . Document identity 443 identifies document 447 . Document user identity 444 identifies the user whose access to the document 447 is affected by the document access policy 453 . In an embodiment, security gateway 150 compares user identity 424 with document user identity 444 . In response to determining that the user identity 424 matches the document user identity 444 , in some embodiments, security gateway 150 allows document 447 with document identity 443 to be accessed by user identity 424 . In another embodiment, security gateway 150 denies access to document 447 with document identity 443 . In denying access, the security gateway 150 may disconnect application session 182 or discard data packets 439 . In some embodiments, security gateway 150 confirms that data packets 439 include document identity 443 . In response to confirming that data packets 439 include document identity 443 , security gateway 150 applies document access policy 453 .
[0082] In some embodiments security policy 402 includes time 457 where security policy 402 is applicable within time 457 . In some embodiments, time 457 indicates a beginning time such as 8 am, 4 pm, midnight. In an embodiment, time 457 indicates a time range such as 8 am to 10 am, 7 pm to 5 am, morning hours, lunch, rush hour, prime time. Security gateway 150 compares clock 359 with time 457 and determines if security policy 402 is applicable.
[0083] In some embodiments, security gateway 150 generates security message 472 when security gateway 150 determines if security policy 402 is applicable to application session 182 for user identity 424 . In some embodiments, security gateway generates security message 472 when security gateway 150 applies security policy 402 to application session 182 . In some embodiments, security report 475 includes security message 472 . In one example, security message 472 includes security policy 402 and user identity 424 . In one example, security message 472 includes the actions security gateway 150 applies to application session 182 using security policy 402 .
[0084] The invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, etc.
[0085] Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.
[0086] The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD.
[0087] A data processing system suitable for storing and/or executing program code will include at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution.
[0088] Input/output or I/O devices (including but not limited to keyboards, displays, point devices, etc.) can be coupled to the system either directly or through intervening I/O controllers.
[0089] Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.
[0090] Foregoing described embodiments of the invention are provided as illustrations and descriptions. They are not intended to limit the invention to precise form described. In particular, it is contemplated that functional implementation of invention described herein may be implemented equivalently in hardware, software, firmware, and/or other available functional components or building blocks, and that networks may be wired, wireless, or a combination of wired and wireless. Other variations and embodiments are possible in light of above teachings, and it is thus intended that the scope of invention not be limited by this Detailed Description, but rather by the Claims following. | Applying a security policy to an application session, includes: recognizing the application session between a network and an application via a security gateway; determining by the security gateway a user identity of the application session using information about the application session; obtaining by the security gateway the security policy comprising network parameters mapped to the user identity; and applying the security policy to the application session by the security gateway. The user identity may be a network user identity or an application user identity recognized from packets of the application session. The security policy may comprise a network traffic policy mapped and/or a document access policy mapped to the user identity, where the network traffic policy is applied to the application session. The security gateway may further generate a security report concerning the application of the security policy to the application session. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to apparatus for tracking and positioning PC card devices in rapid succession and, more particularly, but not by way of limitation, it relates to an improved testing device for receiving and testing PC card devices in rapid succession with rejection of faulty devices.
2. Description of the Prior Art
The closest prior art should be the U.S. Pat. No. 5,050,023 entitled "DISKETTE SEQUENTIAL LOADING AND STORING APPARATUS" as issued on Sep. 17, 1991 in the name of H. D. Ashby, the present inventor. This patent describes a device for handling storage diskette members utilizing a magazine that directs diskettes alternately along dual drop chutes whereupon the individual diskettes are each tested in a disk drive apparatus. Means are then provided for directing tested diskettes along selected routing as designated for non-defective and defective diskette containers. Another U.S. Pat. No. 4,644,427 in the name of the same inventor and entitled "DISKETTE LOADING APPARATUS" would be of general interest as it relates to testing and handling apparatus for diskettes. This loading apparatus also utilizes a gravity drop delivery chute which functions in coaction with a disk drive apparatus for sorting and processing. Other patents having some pertinence to the present invention are included in the Information Disclosure Statement.
SUMMARY OF THE INVENTION
The present invention provides an improved cartridge-type loading apparatus for handling, testing and sorting modular PC cards of various types. Each of the PC cards is encased in a standard jacket or wrapper as the pin connections will vary as between the PC cards of different manufacturers. The testing apparatus functions by programmed pneumatic operation to enable electronic testing of modem operation in rapid manner whereby defective and non-defective modems are separated. Modems to be tested are aligned in an input storage chute whereupon the units are successively fed into a gravity-drop slideway. A modem under test progresses down the slideway under control of pneumatic stops through a ready station for intermittent release into a test station whereupon a transverse slide actuator carries the modem into plug interconnection for performance of the test sequence. Upon test completion, the transverse cylinder is reversed whereupon the modem interconnection is broken and released, and the modem continues down the slideway under force of gravity into a first test deposit chute which holds valid tested units, or, it continues on downward to a reject deposit chute if the unit did not pass the clearance test. It should be understood that, while reference is made to modem units, any type of PC card may be tested in the present apparatus.
Therefore, it is an object of the present invention to provide a PC card test apparatus that handles all units in standard wrapper rapidly and safely.
It is also an object of the present invention to provide a PC card testing apparatus that utilizes a gravity drop input mechanism.
It is yet further an object of the invention to provide handling and testing apparatus for handling modem modules in rapid and efficient manner to separate the good modems from the defective.
Finally, it is an object of the present invention to provide a pneumatically controlled, gravity-drop slideway to present standard modem units for electronic testing of operational components.
Other objects and advantages of the invention will be evident from the following detailed description when read in conjunction with the accompanying drawings which illustrate the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the front panel of the testing apparatus;
FIG. 2 is a side view in elevation of the front panel shown in FIG. 1;
FIG. 3 is a depiction of an air regulator and solenoid valve bank employed in the test apparatus;
FIG. 4 is a functional diagram illustrating the testing stages of the apparatus;
FIG. 5 is a top plan view of a standard modem wrapper;
FIG. 6 is an end view of the modem of FIG. 5;
FIG. 7 is the opposite end view of the modem of FIG. 5;
FIG. 8 is a vertical section taken along lines 8--8 of FIG. 1;
FIG. 9 is a plan view of a portion of the front panel of FIG. 1 with the transverse actuator in the open position;
FIG. 10 is a vertical section taken long lines 10--10 of FIG. 9;
FIG. 11 is a plan view of the inside face of the transverse actuator;
FIG. 12 is a vertical section taken along lines 12--12 of FIG. 11;
FIG. 13 is a view of the inside face of the transverse actuator in actuated position carrying the modem into pin connection; and
FIG. 14 is a vertical section taken along lines 14--14 of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 illustrate a modem handling apparatus 10. The modem handling apparatus 10 in operational attitude is disposed at an angle as shown in FIG. 2 as a right angularly shaped test machine housing (not shown) supports the chassis 12. The tester frame also houses the electronic circuitry (not shown) beneath the chassis 12 as the chassis 12 is rotatably supported on lower rollers 14 and 16 supported in the tester frame. When operationally assembled, the chassis 12 is detachably locked into the tester frame; however, the chassis 12 can be unlocked at the top and rotated forward and down to gain access to the circuitry and/or other structure contained behind the chassis 12. One such form of structure is a pneumatic supply 18 as shown in FIG. 3.
The air supply connector 18 is mounted behind the chassis 12 within the tester frame and receives air input from an external supply at conduit 20 connected to a commercially available type of air regulator 22. The air regulator 22 is a type capable of regulation between 10 and 100 psi and it is controlled to apply about 80 psi air under pressure via tube 24 to an air manifold 26. The air manifold 26 includes nine identical solenoid valves 28a through 28i which are actuatable to produce air pressure output on respective ones of tubes No. 1 through No. 9 that are applied to the testing apparatus 10 variously, as will be further described. Selective control of the solenoid valves 28a through 28i is effected via the multi-conductor cable input 30 which comes from the electronic circuitry (not shown). Most testing circuitry is supplied by the customer/user.
Referring again to FIGS. 1 and 2, the chassis 12 is structured around a chassis plate 32 that is milled to exhibit certain features. Thus, the plate 32 is milled to form a right hand guideway 34 along the length of plate 32, and it is further milled to form a wider slideway 36. The left hand side of chassis plate 32 is also formed with a first shallow milling of a guideway 38 which is then stepped down to the slideway 36. The slideway 36 is milled about 1/16th inch deeper than the guideways 34 and 38 and a pair of MYLAR™ TEFLON™ strips are overlai and 38 to aid the slidability of the modems.
Right angle track numbers 40 and 42 are disposed on each side of the plate 32 adjacent the outer edges of guideways 38 and 34 and secured by suitable fasteners to extend perpendicular therefrom. The angle tracks 40 and 42 are disposed to receive a plurality of modem cartridges for individual dispensing into the slideway 36 as will be further described. A pair of feed gate subassemblies 44 and 46 function coactively to move the individual modems into release position down the slideway 36, as will be further described. The feed gate subassemblies 44 consist of respective air cylinder assemblies 48 and 50 that are energized by the No. 9 air tubes coming from air supply 18. The cylinder assembly 48 is secured by bolting to the slideway 36 while the air cylinder assembly 50 is secured to a transverse plate 52 that is secured to each side of chassis plate 32 and bridging the slideway 36.
Immediately adjacent transverse plate 52 is a test box 54 which is arrayed transversely across the chassis plate 32. The test box 54 is mounted on a transverse test plate 56 (FIG. 2) which is hingedly affixed to the opposite side hinge arms 58 and 60 that are pivotally mounted within indentures 62 and 64 in opposite sides of the chassis plate 32. The test box 54 functions to seize and move a modem transversely into test connection from the slideway 36, as will be further described below. As can be seen in FIG. 2, the test plate 56 is actuatable into the 90° open position as shown by phantom lines as hinge plate 58 is elevated to its open position.
On the underside of chassis plate 32 a pair of air cylinders 66 responsive to air control tube No. 8 are actuatable to extend cylinder pistons 68 upward into guideway 36 (see FIG. 4) so as to interfere with modem movement down the slideway 36. Pistons 68 hold a downward moving modem at a first ready stage 126 for a designated time. When the air cylinders 66 are released, i.e., pressure tube No. 8 is off, the modem is allowed to drop further into the test stage 128 beneath test box 54 whereupon a pair of air cylinders 70, responsive to air source tubes No. 7, are actuated to move respective pistons 72 into interfering position along slideway 36 to hold the modem at the test stage (FIG. 4). An optical sensor 74 provides indication to the test sequence controller that a modem is in proper transversely oriented position.
A guide foot 76 having opposite side guide blocks 78 and 80 is positioned along slideway 38 (see FIG. 9) so that alignment tabs 82 and 84 are normally positioned upward along slideway 38 thereby to align the plug edge of the modem prior to the transverse plug-in movement whereupon the tab ends 82 and 84 will be retracted. The guide foot 76 is moved by actuation of air cylinder 86. The piston 88 of air cylinder 86 is connected by a screw fastener to a portion 90 of chassis plate 32 that extends between guide feet 78 and 80. Thus, when air cylinder 86 is actuated, air cylinder 86 moves downward along with the guide member 76 so that the guide feet 78 and 84 cease interfering with transverse movement of the modem.
As shown in FIG. 1, a test position is defined by opposite side angle chutes 90 and 92 which receive all modems that test good, and properly tested modems are moved outward along angle chutes 90 and 92 by means of a pusher foot 94. Pusher foot 94 is timely controlled by an air cylinder assembly 96 (see FIG. 2) which is connected by a cylinder piston 99 and screw 98 (FIG. 14) under control of pneumatic pressure from tube source No. 1. In the event that the modem does not test good, pneumatic source No. 2 actuates an air cylinder 100 to retract a snubber foot 102 that allows the modem to pass on down the slideway 36 and into the reject deposit (see also FIG. 4) within angle chutes 104 and 106. When a modem is rejected down into angle chutes 104 and 106 an air cylinder assembly 108 connected to piston 111 (FIG. 14) is actuated via pneumatic source No. 4 to move pusher foot 109 and index the modem outward. The plurality of spring-loaded detents 112 are screw fastened at an angle into either the angle chutes 90, 92 and 104, 106 or they are positioned by means of securing blocks 114 affixed along the slideways 38 and 34. The particular types of detent mechanism are fully disclosed in U.S. Pat. No. 5,050,023.
A lever arm 116 (FIG. 2) is formed integral with hinge arm 60 (FIG. 1) to provide connection to a piston rod 118 of an air cylinder 120 (FIG. 2). The base of air cylinder 120 is pivotally connected to a bracket 122 extending from chassis plate 32. Thus, air cylinder 120 may be actuated to extend piston rod 118 thereby to rotate the hinge arms 58 and 60 upward to place the test box 54 in its 90° open position. This capability is desirable for maintenance and adjustment of the transverse positioning mechanism, as will be further described.
FIG. 4 illustrates in idealized form the length and stages of the gravity drop slideway 36. An uppermost storage stage 124 receives input of modems to be tested as they are stored in alignment in angle chutes 40, 42 (see FIG. 1) inclined for downward feed. The modems are fed by feed gate subassemblies 44 and 46 to fall against slideway 36 and opposite side glideways 38 and 34 thereafter to slide downward into the first ready stage 126. Pneumatic source No. 8 is then energized to actuate cylinders 66 to expel pistons 68 within the slideway so that the modem is stopped in slideway 36. Test stage 128 being empty, the cylinders 66 are then deactivated to withdraw pistons 68 and allow the modem to fall down to test stage 128 whereupon a pair of air cylinders 70 will have been activated to expel the pistons 72 and block further downward progression of the modem. An optical sensor 74 verifies proper positioning of the modem within test stage 128 whereupon the transverse slide mechanism is actuated to secure the modem for actual electrical testing, as will be further described below. After the test, the cylinders 70 are deactivated to withdraw piston 72 which allows the disconnected modem to fall on down slideway 36 into position in angle chutes 90 and 92. If the modem tested good, it remains in the angle chute 90 and 92; but, if the modem tested not good, the air cylinder 100 actuated by air source No. 2 allows the modem to fall further downward into the reject deposit angle chutes 104 and 106.
FIG. 5 illustrates a standard modem cartridge 134, a cartridge type that is utilized by most modem suppliers. FIG. 6 shows the first end 136 configurations, a large plurality of hole pairs 138. The opposite side keyways 138 and 140 and the number of hole pairs 138 may vary as between different modem manufacturers. FIG. 7 illustrates the second end 142 as it includes a limited number of configured contacts 144 and these too will vary with the different manufacturers. Opposite side energizing contacts 146 and 148 (FIG. 5) are disposed along each edge of the modem 134.
FIG. 8 illustrates a section taken along lines 8--8 of FIG. 1, a sectional view of the storage stage 124 and feed gate subassemblies 44 and 46. The air cylinder assembly 48 consists of a cylinder block 150 having a guide bore 152 and a cylinder bore 154. The guide bore 152 is counterbored to form a shoulder 156 there-within. The cylinder bore 154 is formed with a counterbore 158. The cylinder block 150 is seated by suitable fasteners to the slideway 36 of chassis plate 32.
An air cylinder 160 is coupled via tubing to air source No. 9 and is slidably retained within cylinder bore 154 as the cylinder 160 is secured to an angle plate 162 having a support plate 164 extending therefrom. The cylinder 160 has a piston 166 and rod 168 connecting to a clamping plate 170 as the opposite end of cylinder 160 includes a stop washer 172 as retained by a suitable screw fastener 174. A helical spring 176 is disposed around cylinder 160 within the counterbore 158 and tends to bias the cylinder 160 outward from bore 158.
The lower feed gate subassembly 46 is constructed in the same manner as subassembly 44 except that a shorter cylinder block 180 is used since the cylinder block 180 has to be secured on top of the transverse plate 52 defining the slideway 36 path therebeneath. Suitable fasteners (not shown) on each side of cylinder block 180 secure the block into transverse plate 52 and a suitable side emerging port is connected to the air source No. 9.
The remainder of feed gate subassembly 46 is constructed identically to subassembly 44, previously described. Thus, the cylinder block 180 includes an elongate guide bore 182 formed with an internal shoulder 184, and it is further formed with a cylinder bore 186 having a counterbore 188. A pneumatic cylinder 190 is slidably seated within cylinder bore 186 with a stop washer 192 secured by means of a screw fastener 194 on one end, and with the opposite end secured to an angle plate 196 having a support plate 198. The cylinder 190 includes a piston 200 and rod 202 that are connected through the angle plate 196 to a clamp plate 204. A helical spring 206 is seated around cylinder 190 within counterbore 188 to provide bias outwardly toward angle plate 196.
Each of the feed gate subassemblies 44 and 46 operates concurrently and in identical manner. A plurality of stacked modems resting in downward disposition between angle chutes 40 and 42 as cylinders 160 and 190 are actuated from air source No. 9 so that each of respective clamp plates 170 and 204 move toward the edges of the modem stack for limited movement, limited by the amount of slack in respective guide rods 171 and 210. Thus, when the heads of guide rods 171 and 210 reach the respective bore shoulders 156 and 184 their movement stops (as at dash line position 212) and the respective sliding cylinders 160 and 190 are forced to move slidingly in the opposite direction. Thus, as cylinder 160 moves to the position of dash lines 214 the angle plate 162 and support plate 164 are also retracted whereupon a single modem separated by plate teeth 216 and 218 drops down into the slideway 36 whereupon it is free to slide downward along the gravity drop route (beneath transverse plate 52). The feed gate subassembly 46 functions in the same manner at the same time in coaction with subassembly 44. Initial disclosure of the similar feed gate subassemblies is more fully set forth in the U.S. Pat. No. 5,050,023, aforementioned.
FIG. 9 shows a plan view of the chassis plate 32, in the area of the test box 54, with the test box moved to its 90° upright position (as shown in phantom in FIG. 2). Downward modem traverse is indicated by arrow 220 and test box 54 is shown in its raised position exposing the various components on transverse test plate 56. These components are a test receptacle 222, a catch plate 224 and a driver assembly 226, all of which will be more particularly discussed with respect to FIGS. 11, 12 and 13. A hole 228 is formed in the forward wall of test box 54 to allow space for recoil of the screw fastener 194 when pneumatic cylinder 190 (FIG. 8) exhibits the recoil phase.
A transverse plate sector 230 of chassis plate 32 includes laterally spaced holes for receiving the pneumatic cylinder pistons 68 (cylinder assembly 66), and then below that the spaced pistons 72 from the pneumatic cylinders 70. The optical sensor 74 is positioned between and slightly above the level of cylinder pistons 72 which actuate to align the modem for the transverse plug-in movement. Referring also to FIG. 10, a hole 232 formed in chassis plate 32 provides space for catch plate 224 and driver assembly 226 when test box 54 is in its closed position. A pair of spaced square holes 234 and 236 allow for insertion of guide blocks 78 and 80 upward therethrough. Each of the guide blocks 78 and 80 are formed with respective alignment tabs 82 and 84 which serve to define the edge of the modem slideway in the sector 230. The guide blocks 78 and 80 are upward extensions of the guide foot 76 (FIG. 2) which is rigidly affixed to the air cylinder 86 while the air cylinder piston 88 is threadedly secured by screw 238 to the portion 90 of chassis plate 32. In this instance, the air cylinder 86 is secured to the guide foot 76 while the piston member is secured fast to portion 90 of chassis plate 32 so that actuation of air cylinder 86 extending the piston moves both cylinder 86 and guide foot 76 downward or away from chassis plate 32 thereby to move the alignment tabs 82 and 84 into non-interfering position relative to the surface of sector 230.
FIG. 11 shows in plan view the normally downward oriented transverse test plate 56 as it would be viewed in the open position. Thus, when closed, the actual direction of modem gravitational drop would be in the direction of arrow 240 relative to test plate 56. Located on test plate 56 are the modem test receptacle 222, the catch plate 224 and the driver assembly 226.
The test receptacle 222 receives the first end 136 of the modem which presents a large plurality of hole pairs 138 (see also FIG. 12). The receptacle 222 carries a matching plurality of pins 242 which extend into a connector socket 244. A suitable connector providing all of the requisite test connections is connected to socket 244, and a multi-conductor cable is then led back behind the chassis for connection to the electronic circuitry (not shown). The test connection circuitry and connector will vary with each different type of modem and the modem test receptacles 222 are interchangeable as secured by allen screws 246. As shown also in FIG. 12, the test receptacle 222 includes a central receptacle 248 and opposite side guides 250 and 252 which are each keyed to match the side key ways 138 and 140 of the particular modem unit.
The test plate 56 is then milled to a second level along line 254 to define a slide sector 256 whereupon plate 56 resumes its original plane along milling line 258. A cut out 259 of generally rectangular dimension is made in test plate 56 to form a slideway for the catch plate 224 and driver assembly 226 which extend upward therethrough. As shown in FIG. 12, a slide plate 260 is adapted to slide beneath test plate 56 in a milled out slideway 262 terminating in a stop wall 264. The other end of slide plate 260 has an upright plate 266 which supports the catch plate 224 thereon that presents an overhang facing toward the test receptacle 222.
The driver assembly 226 includes a top plate 268 secured on top of a spacer plate 270 which is fastened on a pivot plate 272 that carries a pivot connector 274 threadedly secured thereunder. The forward portion of pivot block 272 is formed to include a stop plate 276 which extends into sliding, interlocking engagement within a transverse slot 278 formed on the underside of slide plate 260. The pivot post 274 is connected to a socket connector 280 secured on piston rod 282 of a pneumatic cylinder 284. The cylinder 284 is anchored within test box 54 by means of support fasteners 286 and 288, and air is provided from air sources No. 5 and No. 3 to respective sides of the air piston 290.
The spacer plate 270 includes a horizontal slot 291 which carries a key plug 293, a multi-pin, keyed plug for insertion in the configured contact receptacle 144 of the modem end 142. Key plug 293 is connected to a multi-conductor cable 295 and a forward end 297 is shaped to fit through a horizontal slot 299 (FIG. 12) in upright plate 266 of catch plate 224. Thus, with initial closure actuation of cylinder 284, the key plug 293 is engaged with modem receptacle 144.
FIG. 12 shows the test box 54 in its full open position as air cylinder piston rod 282 is fully extended to carry driver assembly 226 fully to the right, while the stop plate 276, inter-locking in slot 278, pulls the slide plate 260 fully to its rightward extent. Modem 134 (dash lines) then slides down into slide sector 256 (FIG. 11). Keep in mind that during operation the test plate 56 is closed against slideway sector 230 of chassis plate 32 (see FIG. 9) and the modem 134 slides downward in the direction of arrow 240 to its position as shown in FIGS. 11 and 12. Air source No. 5 is then energized to drive the piston 290 to retract the piston rod 282 which begins the transverse movement of driver assembly 226. As the extension rod 282 is retracted, driver assembly 226 moves leftward until the extension stop plate 276 locks into abutment in slot 278 whereupon the key plug forward end 297 is engaged in modem receptacle 144. Thereafter, both driver assembly 226, slide plate 260 and catch plate 224 proceed leftward to engage the modem 134. As piston 290 and piston rod 282 continue to full closure, as shown in FIG. 13 indicating the transverse movement by arrow 294, the catch plate 224 captures over the second end 142 of modem 134 to move the first end 136 into the respective edge guides 250 and 252 (FIG. 11) and, finally, into pin/hole engagement of pins 242 in central test receptacle 248. Pins 281 and 283 extending from slide plate 260 through respective slots 285 and 287 are carried into the central receptacle 248 by the modem front edge during transverse closure of slide plate 260. Then, on reversal of slide plate 260, the pins 281 and 283 function initially to disengage the modem hole array 138 from the receptacle pins 242. FIG. 13 illustrates the modem 134 when finally carried transversely into its pin-connected test position whereupon a series of automatically and/or purposefully effected circuit tests are made by means of the connector (not shown) which is placed on socket 244.
When the test is complete, air pressure is applied from source No. 3 to urge piston 290 rightward thereby to extend the piston rod 282 and start the traverse of driver assembly 226. The initial transverse movement for approximately the length of slot 278 beneath slide plate 260 disengages holes 138 by means of pins 281 and 283 and continued transverse movement of slide plate 260 to traverse the length of slideway 262 effects total disengagement from test receptacle 222 and withdrawal of the modem 134 to the slideway sector 256 (FIG. 12) whereupon the modem 134 is free to drop, under force of gravity, into the test and/or reject deposits.
FIG. 14 illustrates the structure of the test deposit stage 130 and reject deposit stage 132. Tested modems slide under gravitational force down slideway 36, and if the unit tested good, air cylinder 100 will be activated to extend rubber snubber 102 adjacent the slideway 36 to stop the fall of a tested modem 134. The air cylinder assembly 96 is then energized from air source No. 1 to extend piston member No. 99 and pusher foot 94 thereby to move the modem unit past the detents 113 and into the right angle tracks 92 and 90 (see also FIG. 1). In the event that the modem does not test good, the air cylinder 100 is not actuated thereby to withhold rubber snubber 102, and allow the down-falling modem to fall on down to the lower level adjacent the right angle tracks 104 and 106. The air cylinder assembly 108 is then activated from air source No. 4 to extend piston 111 and pusher foot 109 thereby to move the failed modem past the detents 113 into the reject deposit storage of angle tracks 104 and 106.
The foregoing discloses a novel modem handling apparatus that enables rapid and efficient test procedures to be performed on individual modem units. The apparatus uses a gravity conveyance system for moving individual modems from a storage stage through test stages to final deposit, either test or reject classified. The testing apparatus has a cycle time that is somewhat under two seconds. That is, the time required for the apparatus to handle the modem through its traverse and plug-in stages, and any variations in time greater than the basic cycle time will be that time required to perform the test procedures as entered by the customer or utilizer of the testing apparatus. There is a great variety of modem plugs which are also selected by the customer user for the particular modem device and changeable components may readily be employed in the operation.
It should be understood that the present apparatus might be used for conveyance and handling of a wide variety of PC cards and similar products. While the device as disclosed functions using pneumatic control and actuation components, either hydraulic or electro-mechanical equivalents may be utilized.
Changes may be made in the combination and arrangement of elements as heretofore set forth in the specification and shown in the drawings; it being understood that changes may be made in the embodiments disclosed without departing from the spirit and scope of the invention as defined in the following claims. | Apparatus for handing and testing PC cards and, more particularly, modem cartridge units. The apparatus uses a gravity drop conveyance or slideway in combination with transverse test coupling unit. Feed gate apparatus separates and singly drops each PC card for drop down the chassis slideway and into a test position beneath a test box. The test box is then actuated transversely to connect test plugs to each side of the PC card which then undergoes a predetermined test sequence. Test PC cards are then further dropped along to slideway to separation and classification stages. | 1 |
FIELD OF THE INVENTION
[0001] The field of the invention is dispensing materials, especially automated dispensing of a first material at a flow rate and quantity that is dependent on the dispensed quantity and/or flow rate of a second dispensed material.
BACKGROUND OF THE INVENTION
[0002] Automation in dispensing materials is often performed using one or more weighing devices to quantify flow of a product at a particular location. For example, dispensation from a feed source can be monitored/controlled using a loss-in-weight feeder in which load cells on the feed source provide a quantitative signal indicating the actual material flow. In further downstream locations, belt scales can be used to provide a quantitative measure of material flow. Typical examples for such devices and methods are shown in U.S. Pat. Nos. 5,081,600 and 6,446,836, and 5,296,654.
[0003] While such devices and methods are often satisfactory for situations where the flow of the material must remain constant, currently known devices and methods have significant difficulties where the flow rate of a first material needs to be adjusted to a variable flow rate of a second material to retain a substantially constant ratio of the first and second materials. To circumvent problems associated with variable flow rates, the continuous flow rate may be at least temporarily converted to a batch process where a fixed quantity of the first material is added to the second material once the second material has reached a predetermined weight in a holding or otherwise accumulating device. While such batch processing advantageously increases accuracy of the ratio between first and second materials, batch processing is not always suitable for all operations.
[0004] Consequently, although various configurations and methods for dispensing materials are known in the art, all or almost all of them suffer from one or more disadvantages. Thus, there is still a need to provide improved methods and configurations for dispensing a material at a flow rate and quantity that is a function of the flow rate and quantity of another material.
SUMMARY OF THE INVENTION
[0005] The present invention is directed to devices and methods for adjusting the feed rate of a continuously flowing material to a variable feed rate of another continuously moving material, thus allowing combination of the materials at a constant and predetermined ratio. Most preferably, the one material is dispensed from a loss-in-weight feeder while the other material is provided via a conveyor belt with a weigh belt. Adjustment in preferred devices and methods is automated and controlled via a PLC (programmable logic controller) that includes a PID (proportional-integral-derivative) controller.
[0006] In one aspect of the inventive subject matter, a method of adjusting a first feed rate of a continuously flowing first material from a feeder to a variable second feed rate of a continuously moving second material on a conveyor includes a step of feeding a plurality of first signals from a weigh belt coupled to the conveyor and a plurality of second signals from a feeder load cell to a PLC. The PLC is then used to (a) calculate the first feed rate based on a moving average of the plurality of first signals, (b) set the feeder to the calculated first feed rate to so operate the feeder in an open loop mode, and (c) calculate and set a corrected feed rate based on the plurality of second signals to so operate the feeder in a closed loop mode when the corrected feed rate and the first feed rate have a difference less than a predetermined amount. When the corrected feed rate and the first feed rate have a difference more than the predetermined amount (e.g., at least 20%), the PLC reverts back to open loop mode. It is also contemplated that the PLC reverts to open loop mode when the plurality of second signals are indicative of a low level at which a feeder refill is requested. Most typically, the feeder load cell is part of a loss-in-weight feeder, and the conveyor comprises a weigh belt.
[0007] In particularly contemplated methods, it is preferred that the variable second feed rate has substantial variability, typically at least 10%, more typically at least 20%, and even more typically at least 35%. It is further generally preferred that the plurality of first signals and/or the plurality of second signals correspond to weight measurement signals taken at a frequency of between 1 min −1 and 1 s −1 . Especially at relatively lower frequencies, it is preferred that the moving average is an exponentially weighted moving average, however, many other moving average determinations are also deemed suitable. Where needed, the PLC may further be programmed to allow manual mode to control the first and/or second feed rate.
[0008] With respect to the determination of the calculation of the corrected feed rate it is preferred that the programmable logic controller comprises a PID controller that calculates and sets the corrected feed rate.
[0009] Thus, and viewed from a different perspective, a method of controlling continuous flow of a material will include a step of calculating a first material flow requirement based on a moving average quantification of a second material flow (the second material flow will have substantial variability, typically at least 10%, more typically at least 20%, and most typically at least 30%). In another step, feedback quantification of an actual first material flow is used to adjust the calculated first material flow requirement to so obtain a corrected first material flow, and feedback quantification is ignored when the first material flow requirement differs from the corrected first material flow in at least a predetermined amount (e.g., at least 20%).
[0010] Most typically, the moving average quantification is calculated in a PLC (e.g., as exponentially weighted moving average), and the calculated first material flow requirement is determined using a PID controller unit of the PLC. For example, the moving average quantification may be based on a plurality of signals from a weigh belt and the feedback quantification may be based on a plurality of signals from a loss-in-weight feeder.
[0011] Consequently, a plant is contemplated that includes a feeder that continuously provides a first material at a first feed rate to a conveyor that continuously provides variable amounts of a second material at a variable second feed rate. A PLC is operationally coupled to a weigh belt of the conveyor and receives a plurality of first signals from the weigh belt and a plurality of second signals from a load cell of the feeder. It is generally preferred that the PLC is programmed to calculate and/or set the first feed rate of the first material based on a moving average of the plurality of first signals to so operate the feeder in an open loop mode, and that the PLC is further programmed to calculate and/or set a corrected feed rate based on the plurality of second signals to so operate the feeder in a closed loop mode when the corrected feed rate and the first feed rate have a difference less than a predetermined amount (e.g., less than 20%). It is still further preferred that the programmable logic controller is also programmed to revert to the open loop mode when the corrected feed rate and the first feed rate have a difference more than the predetermined amount (e.g., at least 20%).
[0012] As before, it is preferred that the moving average quantification is determined in the PLC and is an exponentially weighted moving average, and that a PID controller calculates the corrected feed rate. Additionally, it is preferred that the PLC is programmed to allow manual control of the first and/or second feed rate.
[0013] Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWING
[0014] FIG. 1 is an exemplary schematic illustration of a continuous ingredient system according to the inventive subject matter.
DETAILED DESCRIPTION
[0015] The present invention is directed to devices and methods for continuous addition of one material to a continuous and variable stream of another material at a predetermined ratio. Most preferably, contemplated systems and methods employ a combination of hardware and software to accurately and flexibly control the combination of materials in predetermined ratios.
[0016] Most preferably, contemplated systems and methods use a PLC in combination with a weigh belt of a conveyor system and a loss-in-weight feeder having one or more load cells. In especially preferred systems and methods, the PLC receives load signals from the weigh belt and calculates a setpoint (e.g., via an earned weight moving average filter) for the feeder in an open loop control. The PLC further receives load signals from the load cells of the loss-in-weight feeder, which are then used as a feedback signal in the PLC to so operate in closed loop control. Most typically, a PID controller in the PLC will be used to control the rate of ingredient addition from the feeder in the closed loop control. To maintain large-grain and fine-grain control, the PLC reverts to open-loop control when at any time the filtered setpoint and feedback are more than predetermined value (e.g., 20%) apart. It is further generally preferred that the PLC reverts to open loop any time the feeder is below a certain weight (e.g., when a refill is requested).
[0017] Thus, it should be appreciated that devices and methods according to the inventive subject matter will allow replacement of individually controlled hardware for batch operation with software based PLC control that not only reduces points of failure, but also improves performance through use of flexible operating modes. In contemplated systems and methods, three modes of operation are available to the operator, a manual setting/fixed rate, open loop mode, and closed loop mode. Most typically, the setpoint for open loop mode form can be calculated as y=mx+b where x is motor speed (e.g., for feeder auger) and y is the flow rate (e.g., measured lbs/hr). Closed-loop feedback control through a PID controller contained in the PLC can be implemented by calculating the loss-in-weight in, for example, one second intervals, and a calculation in the PLC will determine when it is applicable to close the loop for tighter control. Among various other advantages, it should be noted that such system will perform especially well in continuous operations due of the linear nature of material addition. Furthermore, it should be noted that since contemplated systems and methods are software based, they can be adjusted for use with different materials and processes. Moreover, stand-alone controllers are eliminated, which also eliminates a point of failure and a source of error.
[0018] One exemplary configuration is schematically depicted in FIG. 1 where dispensing system 100 includes a feeder 110 that provides a first material 112 to the conveyor 120 that includes a weigh belt 124 weighing the variable continuous flow of the second material 122 . The feeder 110 and the conveyor 120 are coupled to the PLC 130 that further preferably includes a PID controller 132 . In the example of FIG. 1 , the weigh belt 124 provides first signals 126 A to the PLC 130 , which may further provide signals 126 B to the conveyor (typically the drive mechanism) to control operation of the conveyor. The PLC also receives second signals 116 from the load cells 114 of the feeder 110 , and provides first and corrected signals 118 A/ 118 B to the dispensing mechanism (e.g., auger drive) of the feeder 110 .
[0019] In a typical use of such dispensing system, a first feed rate of a normally continuously flowing first material from a feeder can be adjusted to a variable second feed rate (e.g., varies at least 5% from average, more typically at least 10% from average, most typically at least 15% from average) of a continuously moving second material on a conveyor. In such method, it is generally preferred that a plurality of first signals from the weigh belt that is coupled to the conveyor and a plurality of second signals from a feeder load cell are transmitted to a PLC. The PLC is then used to calculate the first feed rate based on a moving average of the plurality of first signals, and further used to set the feeder to the calculated first feed rate to so operate the feeder in an open loop. It is further especially preferred to use the PLC to calculate and set a corrected feed rate based on the plurality of second signals (via calculation, typically using a moving average calculation) to so operate the feeder in a closed loop under conditions where the corrected feed rate and the first feed rate have a difference that is less than a predetermined amount. The PLC will revert to the open loop when the corrected feed rate and the first feed rate have a difference that is greater than the predetermined amount.
[0020] Of course, it should be recognized that contemplated systems and methods may be modified in various manners without departing from the inventive concept presented herein. For example, the conveyor system need not necessarily be a conveyor belt system with a weigh belt, but may indeed be any system that is capable to deliver a continuous flow of the second material at a variable flow rate. Therefore, suitable alternative implements include chutes, pipes (using gravity or a gas/fluid to propel the second material), augers, buckets, etc. Consequently, the weigh belt may be replaced by various alternative devices for quantitation, and suitable devices will include batch scales, piezo scales, loss-in-weight systems, and optical systems that translate material density (especially for large particulate material) to a calculated weight.
[0021] Consequently, and dependent on the type of material conveyed and quantification system used, it should be noted that the first and second weight measurement signals may be taken at various intervals. However, it is generally preferred that the weight measurement signals are taken or transferred to the PLC at a frequency of between 1 min −1 and 1 s −1 .
[0022] With respect to the variability of the flow rate of the second material it is generally contemplated that the variability is relatively large and will be at least 5% from a long term average, more typically at least 10% from a long term average, even more typically at least 20% from a long term average, and most typically at least 30% from a long term average, wherein the long term average is measured over a period of at least 100-fold the duration of a deviation from an average. Variability of flow rate may be due to various reasons, including variability in supply to the conveyor, grouping (e.g., due to rolling of the material on the conveyor) or clumping of the material, and the variability may be periodic or entirely random. Regardless of the type and amount of the variability it is generally preferred that the signals from the quantification device (typically a weigh belt) are directly transmitted to the PLC, most commonly by wire or RF signal. However, in less preferred aspects, the quantification device may already provide at least a portion of signal processing. For
[0023] The PLC will preferably be programmed to calculate from the signals from the quantification device a calculated or corrected feed rate that is typically translated into a control signal to the feeder mechanism (e.g., control signal to feed auger, pump, or weir) to so control the feed rate. As will be readily appreciated, there are numerous calculations that will be suitable for use in conjunction with the teachings presented herein. However, it is typically preferred that the calculation will include a smoothing/filtering of the data received from the quantification device such that small deviations will be reduced but larger deviations and/or trends will be considered. For example, suitable smoothing/filtering may be implemented by averaging multiple signals over a predetermined interval to so produce a moving average. Such moving average calculation may further be weighted in some manner to so provide a more accurate calculation. For example, weighting may be by time delay, signal difference, cumulative change, etc. However, in most instances, an exponential or earned weighted moving average will be preferred. With respect to the length of the interval of the moving average, it should be noted that the person of ordinary skill in the art will be readily able to select a suitable length without undue experimentation.
[0024] Based on the calculation of the average weight, the desired fraction of material to be added, and the feeder mechanism, the PLC will then determine and set in an open loop mode the calculated first fed rate. Of course, it should be appreciated that any change in measure weight on the conveyor will lead to a newly determined average weight and with that a newly determined/corrected feed rate. Provided the corrected feed rate and the first feed rate have a difference less than a predetermined amount, the PLC will then switch to a closed loop mode in which the plurality of second signals are used as a feedback signal.
[0025] With respect to the plurality of second signals it should be appreciated that the type of second signals will generally depend on the type and/or number of load cells. Moreover, it should be appreciated that while a loss-in-weight load cell feeder is preferred, numerous other quantification devices to provide feedback are also deemed suitable and include batch scales, other loss-in-weight devices, weigh belts, image-analysis based devices, etc. The feedback calculation is most preferably performed using a PID controller that is suitable programmed and preferably part of the PLC. Such feedback control will advantageously improve accuracy and reliability of the material dispensation.
[0026] However, and particularly where the variability in feed rate has a rapid change or relatively significant spike it is typically preferred that the PLC switches from the closed loop mode to the open loop mode to so allow for a relatively fast correction. As soon as the variability is reduced or has been otherwise stabilized, the PLC will once more revert to closed loop mode. Most typically, the switch from the closed loop mode to the open loop mode will be triggered when the difference between the first feed rate and the corrected feed rate is at least 5%, more typically at least 10%, even more typically at least 15%, and most typically at least 20%. Additional triggering events that will cause the PLC to switch from the closed loop mode to the open loop mode include those in which the feedback signal is expected to be compromised. For example, such situations include refills of the feeder, servicing the feeder, switching feed material, etc. Of course, it is generally preferred that the PLC also provides a manual control mode in which the feed rate of the feeder and the feed rate of the conveyor can be modified.
[0027] In still further contemplated systems and methods it should be appreciated that the PLC may also be programmed to modify the feed rate of the second material on the conveyor (or other material transport system). For example, where the plurality of first signals indicate that the variability has a relatively small amplitude but high frequency, the feed rate of the second material may be slowed. On the other hand, and especially where relatively large and periodic amplitudes are measured, the PLC may be programmed to counteract such variations by modulation of the speed of the conveyor. Of course, the modulation of the feed rate of the second material on the conveyor may be performed in conjunction with the correction of the first feed rate, or independently.
[0028] Therefore, and viewed from another perspective, a method of controlling continuous flow of a material will include a step of calculating a first material flow requirement based on a moving average quantification of a second material flow that has a substantial variability (e.g., variability of at least 10%, more typically at least 20%, most typically at least 25%), and another step of using feedback quantification of an actual first material flow to adjust the calculated first material flow requirement to obtain a corrected first material flow. In yet another step, the feedback quantification is ignored when the first material flow requirement differs from the corrected first material flow in at least a predetermined amount, which is typically a value of at least 50% (and more typically at least 75%) of the variability. In particularly preferred methods, PLC-based devices and methods as described above are employed in such methods, wherein the calculated first material flow requirement is determined using a PID controller.
[0029] Therefore, plants are contemplated in which a feeder is configured to continuously provide a first material at a first feed rate to a conveyor, wherein the conveyor is configured to continuously provide variable amounts of a second material at a variable second feed rate. A programmable logic controller is operationally coupled to a weigh belt of the conveyor and receives a plurality of first signals from the weigh belt, and also operationally coupled to a feeder load cell of the feeder and receives a plurality of second signals from the feeder load cell. In particularly preferred plants, the PLC is programmed to calculate and/or set the first feed rate of the first material based on a moving average of the plurality of first signals to so operate the feeder in an open loop, and the PLC is further preferably programmed to calculate and set a corrected feed rate based on the plurality of second signals to so operate the feeder in a closed loop when the corrected feed rate and the first feed rate have a difference less than a predetermined amount. As noted before, it is typically also preferred that the PLC is further programmed to revert to the open loop when the corrected feed rate and the first feed rate have a difference more than the predetermined amount. Thus, it should be appreciated that contemplated configurations and methods can be in numerous plants in which a loss-in-weight minor ingredient addition is part of the plant operation. Normally, such loss-in-weight addition is performed using a stand-alone solution, which is not only expensive, but also adds potential points of error and has significantly less operational flexibility as compared to the systems and methods contemplated herein.
[0030] Thus, specific embodiments and applications of devices and methods for loss-in-weight ingredient addition have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. | Dispensing systems and methods contemplated herein are configured to adjust a first continuous product flow rate to a second continuous but variable flow rate in at least two control modes. Most preferably, a moving average is determined for the second flow rate to provide a first level of control, and a loss-in-weight feedback is determined for the first flow rate to provide a second, finer level of control, which will be abandoned when the feedback moves beyond a predetermined threshold relative to a calculated product flow rate. | 6 |
This is a continuation application of originally filed application Ser. No. 695,541 filed Jan. 28, 1985, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates generally to the heating and cooling of liquids, and more particularly, to the improvements in a compression-type refrigeration system for heating and cooling liquids such as water in a swimming pool.
In the past, many systems have been employed to heat water which utilize resistive-type electric heating elements, or relied upon the combustion of either natural gas or fossil fuel. The former system is well-known to be highly inefficient; the latter system, in addition to also being inefficient, includes the short-comings attendant to combustion, i.e., exhaust gases, a needed source of fuel, high temperature water conduit corrosion, and operational hazards.
A more recent development is disclosed in U.S. Pat. No. 3,513,663, of which applicant was co-inventor. In its broadest sense, this invention teaches te use of conventional refrigeration components, with modification, to heat a first liquid source, e.g., a swimming pool, while simultaneously cooling a second liquid source, e.g., a ground well. Preferably coaxial conduit is utilized in the construction of condenser and evaporator coils for the purpose of achieving opposing, segregated, heat exchange flow between refrigerant and liquid. In operation, when one liquid source is passed through the condenser coil while the second liquid source is passed through the evaporator coil, coaxial, opposing, segregated refrigerant liquid flow in seriatum through the coils will result in efficient heating of the first liquid, while cooling the second liquid. Sensor control and liquid pumping means are also disclosed therein.
The present invention contemplates improvements over the above-disclosed U.S. Patent. One aspect of these improvements includes the elimination of the second or ground liquid source. Another aspect of these improvements comprises liquid and/or refrigerant flow reversal or rerouting to conveniently heat or cool one liquid source. And finally, this invention discloses select use of external fluid flow over condenser or evaporator coils to enhance the coefficient of performance.
BRIEF SUMMARY OF THE INVENTION
The present invention discloses and claims certain improvements in a system for heating a first liquid source which utilizes a refrigeration compressor, a condenser coil, an evaporator coil, a refrigerant, and means for expansion of the compressed refrigerant, all in their well-known interconnected manner, and which also includes a second liquid source. These improvements may be incorporated separately, or in combination, to provide novel benefits in relation to the situational and/or economic restraints.
One such improvement broadly deals with the elimination of the second liquid energy source, which has typically been a ground water well. In areas of the country where ground water is scarce or where there is no other convenient source of heat, this improvement, then, provides liquid source heating or cooling at higher operational efficiencies than previously available. Liquid source heating occurs by extracting heat from the source liquid flow as needed at one point in the refrigerant cycle, then adding substantially greater amounts of heat at another point in the refrigerant cycle. By this means, the liquid source acts as a net resultant heat sink, becoming progressively warmer.
Another broad aspect of the present invention is to optionally alter the path of both first and second liquid source flows in segregated heat exchange fashion through the condenser and evaporator coils. This reversal provides easily controlled and varied heating or cooling of either liquid source.
And still another broad aspect of the present inventive improvement is to provide a source of external fluid flow over either condenser or evaporator coil to achieve increased efficiency of either heating or cooling of either or both liquid sources.
It is therefore an object of this invention to provide improvements in the system for heating and cooling liquids disclosed in U.S. Pat. No. 3,513,663.
It is another object of the above invention to provide optional heating or cooling of either liquid source.
It is yet another object of this invention to eliminate the need for the second liquid source.
It is still another object of this invention to improve performance efficiency for either heating or cooling by the select forced flow of external fluid over specific refrigeration components.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with reference to the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the first embodiment of the invention.
FIG. 2 is a section view through arrows 2--2 in FIG. 1.
FIG. 3 is a schematic view of another embodiment of the present invention.
FIG. 4 is a schematic view of yet another embodiment of the present invention.
FIG. 5 is a schematic view of still another embodiment of the present invention.
FIG. 6 is a schematic view of yet another embodiment of the present invention.
FIG. 7 is a schematic view of still another embodiment of the present invention.
FIG. 8 is a schematic view of yet another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and particularly to FIGS. 1 and 2, one embodiment of the improved system is shown generally at 10, and includes a refrigeration compressor 12, a condenser coil 14, and an evaporator coil 16 in their normal refrigeration cycle relationship. Heated, compressed refrigerant passes out of the compressor 12 into the condenser 14, where it is to be cooled. Thereafter, the refrigerant is passed through means for refrigerant expansion 24 and into the evaporator coil 16, where heat is absorbed during vaporization change of state. This vapor is then suctioned back into the compressor 12, the cycle continuously repeated. Sight glass 26 provides visual indication of adequate refrigerant charge. Electrical control box 18, thermostat control 20, and high/low pressure control switch 22 are interconnected between compressor and a power source (not shown) to regulate operation in a well-known manner.
In FIG. 2 is shown a coaxial coil conduit, preferred and typical of both compressor coil 14 and evaporator coil 16, which preferably are of similar construction and design. Note that any other convenient conduit design for coil and evaporator may be incorporated which allows liquid and refrigerant to flow in a side-by-side heat exchange manner. Refrigerant flows in passage 56 within outer conduit 50 and around inner conduit 54. Liquid pumped by pump 32 from a second liquid reservoir 30 in the direction of arrow A and returned in the direction of arrow B, flows through inner conduit 54 in heat exchange relationship to the refrigerant flowing in the opposite direction through the evaporation coil 16 and compressor coil 14 as indicated by the arrows. In the embodiment of this invention, shown in FIG. 1, the first liquid reservoir 42 and pump 44 are eliminated and liquid flowing from evaporator coil 16 discharge conduit 36 is re-routed via transfer conduit 38 also through the condenser coil 14 and back to the second reservoir 30 via return conduit 40.
The net result of the arrangement shown in FIG. 1 is to heat the liquid in liquid reservoir 30, which may be a swimming pool, hot water storage tank or any other source of liquid which is intended to be heated. As the liquid passes through evaporator coil 16, the vaporizing refrigerant absorbs heat from the liquid, which discharges through conduit 36 at a temperature Y degress cooler than its inlet temperature X degrees. However, the liquid then passes through condenser coil 14, during which time it absorbs heat from the just-compressed refrigerant. The liquid discharges from the condenser coil 14 at a temperature approximtely 2 Y degree warmer than its condenser inlet temperature, X degrees minus Y degrees. The liquid returning to the second liquid reservoir 30 is therefore at a temperature of X degrees plus Y degrees, or Y degrees warmer than when it was pumped out in the direction of arrow A. This net heating effect may be explained by virtue of the compressor 12 converting electrical power into heat by compression of the refrigerant, the converted source of energy for this system. This energy conversion and adsorption is at a considerably higher level of efficiency than either resistive heating elements or fuel combustion. And the need for first liquid reservoir 42, typically ground water, is eliminated in geographic areas where it is unavailable.
Referring to FIG. 3, to add further heat to the liquid returning to the second liquid source 30, a portion 38' of the transfer conduit 38 may be rotated through any convenient additional heat source, preferably partially embedded in the ground 60 sufficiently deep to be warmer than the liquid discharging from the evaporator coil, X degrees minus Y degrees. Alternately, this section of conduit 38' may be routed through a solar panel for passive heat absorption.
Referring to FIG. 4, the boxed portion 70 remains the same as that previously described, as does the construction of the evaporator coil 16. Likewise, only the second liquid reservoir 30 is utilized. However, in this embodiment the output liquid flow A may be partially or totally diverted in the direction of arrow F through bypass conduit 51 by a 0% to 100% proportional three-way regulating valve 46. The evaporator coil 16 requires a certain amount of heat to prevent "icing," but as the liquid and/or the ambient air temperature rises, the liquid flow requirement decreases to provide that heat. Thus, either all, or a portion E of the pump 32 total output flow passes through the evaporator coil 16, or all or a portion F of the total flow bypasses the evaporator coil 16. The position of regulating valve 46 is regulated by the sensed pressure within the evaporator coil 16 and associated electrical controls (not shown). Check valve 48 prevents backflow in bypass conduit 51. All liquid flow is returned to the second reservoir 30 via conduit 40. By this means, the heating effect upon the second liquid reservoir 30, flowing through transfer conduit 47 in the direction of arrow G, is maximized by minimizing the degree to which the liquid flow is passed through, and cooled by, the evaporator coil 16.
Still referring to FIG. 4, to further maximize this heating benefit, a fan 58 may also, or alternatively to liquid bypass, be provided which forces ambient air over the evaporator coil 16. The operation of this fan 58 is regulated by both an ambient temperature sensor control 62 as well as an electrical signal connection 64 to the refrigerant low pressure sensor within the evaporator coil 16. Thus, when both ambient air temperature is sufficiently high, and evapoartor refrigerant pressure is sufficiently low, more external heat is provided to the refrigerant vaporizing within the evaporator coil 16, and thus, more liquid is able to be diverted in the direction of arrow F. In sum, then, where only a single source of liquid is available or utilized, dual or separate evaporator coil 16 heating may be provided by controlled proportional liquid flow bypass and/or external fluid flow over the evaporator coil 16, which external fluid may be ambient air or, as will be described below, a second, separate external liquid flow.
Referring now to FIG. 5, the boxed portion 80 remains the same as in FIG. 1, as does the construction of the evaporator coil 16. In the prior art system as well as that in FIG. 1, the flow of the refrigerant through both evaporator and condenser coils 14 and 16 is opposite to that of the liquid flow. This is so to maximize the heat exchange relationship within the coaxial coil conduit best previously shown in FIG. 2. However, in this alternate embodiment shown in FIG. 5, also intended to maximize heating of the second liquid reservoir 30, and also where the first liquid reservoir 42 is eliminated, the flow of refrigerant and liquid optionally is in the same direction. By this means, the temperture gradient between refrigerant and liquid at any point within the evaporator coil 16 is minimized and, therefore, the cooling effect upon the liquid is also minimized. To accomplish this optional, controlled flow reversal, either the liquid flow is reversed, shown by dotted arrows, or the refrigerant flow is reversed, shown by dotted arrows. The liquid flow reversal is accomplished by three-way valve 66 first diverting the flow to three-way valve 72, then into, through, and out of, the evaporator coil 16 via conduit 88 to three-way valve 68, through check valve 74, and into transfer conduit 100. The refrigerant flow reversal is accomplished by three-way valve 76, first diverting the expanding, vaporizing refrigerant through conduit 82 into the opposite end 88 of the evaporator coil 16, and back out to three-way valve 78, where the refrigerant is carried via conduit 98 through check valve 86 into the compressor. Shut-off valve 84 prevents refrigerant from either flowing from conduit 82 directly back into the compressor or flowing from conduit 98 back into the evaporator coil 16 at 88. Either flow reversal is controlled and made intermittent, and is reversed back, when the low pressure sensor within the evaporator coil signals insufficient refrigerant vapor pressure.
Referring now to FIG. 6, the components within the boxed area 90 remain as in FIG. 1, and the first liquid reservoir is eliminated. However, this embodiment is intended to optionally also cool the second liquid reservoir 30 by totally or partially diverting the liquid flow as it exits the evaporator coil 16 back to the reservoir. By this means, the liquid heating effect imposed by the condensor coil 14 is eliminated. This is accomplished by proportional three-way valve 104, which controlledly returns liquid directly to the reservoir by return conduit 106 in the direction of arrow H. To enhance this liquid cooling effect by prolonging this liquid diversion, fan 102 may be provided to force ambient air across the condenser coil 14. This will at least partially cool the condenser coil 14, depending upon ambient air temperature as sensed at 103, which will shut-off fan 102 if ambient air cannot cool the coil 14. Bypass liquid flow will cease and valve 104 will reroute liquid flow into the condenser coil 14 and/or the system will be shut down when condenser coil 14 pressure rises above a predetermined upper limit. Note that, in this arrangement as described in FIG. 4, the external condenser cooling fluid may be ambient air and/or another fluid such as water.
In FIG. 7, both liquid reservoir 30 an 42 are intended to be utilized, wherein either reservoir may be either heated or cooled, the temperature of the other reservoir being changed oppositely. To accomplish this selective heating or cooling of a particular reservoir, the liquid flow from the pumps 32 and 44 are made reversible within each coil 14 and 16 simultaneously with refrigerant flow reversal coil to coil. In normal operation and as disclosed in prior U.S. Pat. No. 3,513,663, liquid flow from the first liquid reservoir 42, typically a swimming pool, via pump 44 (shown in solid arrows) is directed through condenser coil 14 and returned to the reservoir 42 somewhat heated, while liquid flow from a second reservoir 30, typically ground water, via pump 32 (shown in solid arrows) is directed through evaporator coil 16 and returned to the second reservoir 30 somewhat cooled while refrigerant routing is as in FIG. 1, including the dotted portion. However, for example, to cool the first liquid reservoir 42, e.g., a swimming pool, a liquid flow from pump 44 is diverted at three-way valves 142 and 144 and thus made to flow oppositely through condenser coil 14 in the direction of the dotted arrows through crossover conduits 146 and 148. Likewise, liquid flow from pump 32 is diverted at three-way valves 110 and 112, and thus made to flow oppositely through evaporator coil 16 in the direction of the dotted arrows through crossover conduits 114 and 116. Simultaneously, refrigerant reversing valve 130, such as that available from Alco Controls, No. 401 RD Series Reversing Valves, receiving compressor 12 refrigerant output through conduit 125, selectively diverts refrigerant from its normal path (shown by solid arrows), which is through valve port 132 into valve port 136. Thus, the diverted refrigerant flow (shown by dotted arrows) passes first out of valve port 136, then into the evaporator coil 16 via conduit 138, then through condenser coil 14 and back to the compressor 12 through conduit 145, into valve port 132, exiting valve port 134. By this means, the evaporator coil 16 acts as a condenser and the condenser coil 14 acts as an evaporator, heating the second reservoir 30 and cooling first reservoir 42. Bypass check valve 118 and bypass expansion valve 120 facilitates refrigerant flow only in the direction of the dotted arrows, check valve 122 and expansion valve 124 only allowing refrigerant flow in the direction of the solid arrows. Refrigerant return flow to the compressor 12 is through conduit 140, fed by normal refrigerant flow from conduit 138 into valve port 136 and exiting valve port 134, and in reverse mode, fed by conduit 145 into valve portion 132 and exiting valve port 134. Note that the selective heating or cooling is achieved without co-mingling the two liquid reservoirs 30 and 42, a very desirable situation.
Referring now to FIG. 8, the overall system 10' is similar to that in FIG. 1, except also having a first liquid reservoir 42 in said fluid communication with the condenser coil 14. The point of novelty in this embodiment 10' is the selective addition of a second external source of liquid for heating the evaporator coil 16 or cooling the condenser coil 14. This external fluid flow may be provided over the coils 14 and 16 by fans 152 and 58 respectively, forcing air flow shown by the arrows, or by fluid flow discharge from apertured conduits 164 and 166 supplied by pumps 158 and 154 respectively, in fluid communication with reservoirs 160 and 156 respectively. Return drainage (not shown) to these reservoirs 156 and 160 may also be provided or the fluids may be wasted. When cooler fluid is passed over the external surface of the condenser coil 14, the system energy efficiency ratio (E.E.R.) of the system 10' is increased. When warmer fluid is passed over the external surface of the evaporator coil 16, the system coefficient of performance (C.O.P.) is increased. External fluid flow is regulated by the combination of control signals from the ambient temperature sensor control 162 and the high/low refrigerant pressure sensor 22.
Note that, in an alternative, and perhaps broader, sense within the scope of this invention; either coil may alternately be submerged within a portion of the liquid reservoir or its liquid flow therefrom and back. This coil submersion will still provide a substantial amount of necessary coil heating or cooling and desired liquid cooling or heating. However, the necessity for coaxial or equivalent coil conduit construction would be eliminated.
While the instant invention has been shown and described herein in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent apparatus and articles. | Improvements in the system for heating and cooling liquids as disclosed in prior U.S. Pat. No. 3,513,663. This prior system utilizes components of refrigeration such as a compressor, a condenser coil, an evaporator coil, a refrigerant, and expansion valve, in their well-known interrelationship and includes a first and second liquid source, which are pumped in heat-exchange fashion through segregated condenser and evaporator coils simultaneously with, and in the opposite direction to, that of the refrigerant. One broad improvement embodies the elimination of the second liquid source, typically a ground water well, and to alter normal liquid flow to achieve either heating or cooling. Another broad aspect of this invention is to optionally alter the path of both first and second liquid source flows in segregated heat-exchange fashion through the condenser and evaporator coils, whereby heating or cooling of either liquid source may be easily selected and controlled. Refrigerant flow may also be altered. Yet another embodiment is to provide a source of external fluid flow over either condenser or evaporator coil to increase system efficiency related to either heating or cooling of either or both liquid sources. These improvements may be incorporated into the prior art system separately, or in any combination, to provide unique and novel benefits, depending upon situational and/or economic restraints. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to nitropyrazinyl-and nitropyridinyl- substituted piperazin-3-one and hexahydro-1H-1,4-diazepin-5-one compounds used as sensitizers of hypoxic tumor cells to therapeutic radiation. It also relates to the process of preparing such compounds by reaction of substituted piperazin-3-one and hexahydro-1H-1,4-diazepin-5-one compounds with certain specific chloronitropyrazines and chloronitropyridines defined hereinbelow.
At the present time, certain other unrelated compounds are in experimental clinical use as radiation sensitizers. However, these compounds--for example, metronidazole and misonidazole--suffer from the drawback that they also cause neurotoxicity which limits their usefulness. The compounds of the present invention are effective radiation sensitizers, but are believed to have a more favorable therapeutic ratio.
DETAILED DESCRIPTION OF THE INVENTION
The compounds of the present invention are represented by the general formula: ##STR1## wherein Ar is selected from the group consisting of 3-nitro-2-pyrazinyl and 3-nitro-4-pyridyl, R is selected from the group consisting of hydrogen and hydroxyethyl, and n is either 1 or 2.
The compounds of the present invention are prepared in the following manner:
A lactam of the formula: ##STR2## wherein n is either 1 or 2 and;
R is hydrogen or hydroxyethyl is treated with 2-chloro-3-nitropyrazine or 4-chloro-3-nitropyridine in the presence of a base to produce compound I hereinabove.
The reaction is carried out in a suitable solvent such as a lower alcohol, a polar solvent such as dimethylformamide, dimethylsulfoxide, tetramethylurea, or others such as tetrahydrofuran, glyme, diglyme and pyridine.
A preferred solvent for this reaction is isopropyl alcohol.
The reaction mixture should also contain sufficient base to neutralize the hydrochloric acid formed during the reaction. This base may be in the form of an organic amine such as pyridine or triethylamine or inorganic base such as an alkali metal carbonate, bicarbonate or hydroxide with organic bases being preferred.
The temperature of the reaction is not critical and it is desirably maintained between 0° and 100° C. and preferably between 0° and 25° C. for a period of from 1-25 hours.
The method of treatment of human patients or domestic animals undergoing radiation treatment of malignant disease processes employs the compounds of the present invention in pharmaceutical compositions that are administered orally or intravenously. The dose employed depends on the radiation protocol for each individual patient. In protocols where the radiation dose is divided into a large number of fractions, the drug can be administered at intervals in the schedule and not necessarily with each radiation treatment. It should be noted that the compounds of the present invention are not intended for chronic administration. In general, the drug is administered from 10 minutes to 5 hours prior to the radiation treatment in a dosage of between 0.25 to about 4.0 grams per square meter of body surface.
The dosage range given is the effective dosage range and the decision as to the exact dosage used must be made by the administering physician based on his judgement of the patient's general physical condition. In determining the dose for the individual patient, the physician may begin with an initial dose of 0.25 g/square meter of body surface to determine how well the drug is tolerated and increase the dosage with each suceeding radiation treatment, observing the patient carefully for any drug side effect. The composition to be administered is an effective amount of the active compound and a pharmaceutical carrier for said active compound.
The dosage form for intravenous administration is a sterile isotonic solution. Oral dosage forms such as tablets, capsules, or elixirs are preferred.
Capsules or tablets containing 25, 50, 100 or 500 mg of drug/capsule or tablet are satisfactory for use in the method of treatment of our invention.
The following examples are intended to illustrate but do not limit the process of preparation, product, compositions, or method of treatment aspects of the invention. Temperatures are in degrees Celsius unless otherwise indicated throughout the application.
EXAMPLE 1
1-(3-Nitro-2-pyrazinyl)piperazin-3-one
A solution of 2-chloro-3-nitropyrazine (9.1 g, 57 mmol) in chloroform (100 ml) was added dropwise over 45 minutes to a cooled solution of piperazine-2-one (5.71 g, 57 mmol) and triethylamine (8.0 ml, 57 mmol) in isopropanol (120 ml). After addition was complete, the reaction mixture was allowed to warm to 20°-25° and was stirred at this temperature for 20 hours. The precipitate was removed by filtration and recrystallized from methanol-ethyl acetate-hexane to give 6.96 g (54.7%) of product, m.p. 178°-179°.
EXAMPLE 2
1-(3-Nitro-2-pyrazinyl)hexahydro-1H-1,4-diazepin-5-one
To a solution of hexahydro-1H-1,4-diazepin-5-one (1.14 g, 10 mmol) and triethylamine (1.01 g, 10 mmol) in isopropanol (30 ml) cooled in an ice bath, was added over 30 minutes a solution of 2-chloro-3-nitropyrazine (1.59 g, 10 mmol) in chloroform (20 ml). After addition was complete, the reaction mixture was allowed to warm to 20°-25° and was stirred at this temperature for 20 hours. Solvents were removed under reduced pressure and the residue was partitioned between a saturated aqueous solution of sodium chloride and ethyl acetate. The ethyl acetate extract was dried over anhydrous sodium sulfate, filtered and concentrated to an oil. Flash chromatography over silica gel and elution with 2% methanol -98% chloroform gave pure 1-(3-nitro-2-pyrazinyl)hexahydro-1H-1,4-diazepin-5-one. ##STR3##
EXAMPLE 3
1-(3-Nitro-2-pyrazinyl)-4-(2-hydroxyethyl)piperazin-3-one)
Step A
1-Carbobenzoxy-4-(2-hydroxyethyl)piperazine-3-one
To a solution of 1-carbobenzoxypiperazin-3-one (234 mg, 1.0 mmol) in dimethylformamide (10 ml) under nitrogen was added in one portion, 50% sodium hydride (48 mg, 1 mmol). After stirring at 20°-25° for 30 minutes until all of the sodium hydride had reacted, a solution of 2-(2-bromoethoxy)-tetrahydropyran (209 mg, 1 mmol) in dimethylformamide (2 ml) was added and the reaction mixture stirred at 20°-25° for 20 hours. Solvent was removed at 40°-45° and 0.1 mm and the residue chromatographed over silica gel. Elution with 2% isopropanol -98% methylene chloride gave the pure protected alcohol as an oil.
The tetrahydropyranyl blocking group was removed by heating a solution of the protected alcohol (200 mg, 0.55 mmol) in a mixture of acetic acid (8 ml), tetrahydrofuran (4 ml) and water (2 ml) at 50° for 4 hours. After removing solvents under reduced pressure, the residue was partitioned between saturated sodium bicarbonate solution and ethyl acetate. The ethyl acetate extract was dried over anhydrous sodium sulfate, filtered and concentrated. Chromatography of the residue over silica gel and elution with 5% methanol-95% chloroform gave pure 1-carbobenzoxy-4-(2-hydroxyethyl)piperazine-3-one.
Step B
4-(2-Hydroxyethyl)piperazin-3-one
A solution of 1-carbobenzoxy-4-(2-hydroxyethyl)piperazine-3-one (1.0 g, 35.9 mmol) in absolute ethanol (75 ml) was hydrogenated over a 10% palladium on carbon catalyst (1.0 g) at 20°-25° and an initial pressure of 40 psi for 6 hours. Catalyst was removed by filtration through diatomaceous earth and the filtrate concentrated under reduced pressure to give 4-(2-hydroxyethyl)piperazine-3-one.
Step C
1-(3-Nitro-2-pyrazinyl)-4-(2-hydroxyethyl)piperazin-3-one
A solution of 2-chloro-3-nitropyrazine (1.59 g, 10 mmol) in chloroform (20 ml) was added over 30 minutes to an icebath cooled solution of 4-(2-hydroxyethyl)piperazin-3-one (1.44 g, 10 mmol) and triethylamine (1.01 g, 10 mmol) in isopropanol (30 ml). After addition was complete, the reaction mixture was allowed to warm to 20°-25° and was stirred at this temperature for 20 hours. Solvents were removed under reduced pressure and the residue was partitioned between a saturated aqueous solution of sodium chloride and ethyl acetate. The ethyl acetate extract was dried over anhydrous sodium sulfate, filtered and concentrated to an oil. Flash chromatography over silica gel and elution with 5% methanol-95% chloroform gave 0.90 g (48.6%) of 1-(3-nitro-2-pyrazinyl)-4-(2-hydroxyethyl)piperazin- 3-one. An analytical sample, m.p. 117°-120°, was obtained upon recrystallization from ethyl acetatehexane.
EXAMPLE 4
1-(3-Nitro-4-pyridyl)piperazin-3-one
A solution of 4-chloro-3-nitropyridine (434 mg, 2.74 mmol) in 2 ml of dimethylformamide was added dropwise to a stirred suspension of 548 mg (5.47 mmol) of piperazin-2-one in 2 ml of dimethylformamide at room temperature (approximately 25°) over a period of 30 minutes. A voluminous bright yellow solid began to separate when about half of the solution had been added. After stirring at room temperature for 20 hours, the dimethylformamide was removed by passing a slow stream of nitrogen over the surface of the reaction mixture while heating in a bath at 80° for 18 hours. The yellow crystalline residue, with a small amount of dark brown material on the surface, was recrystallized from 5 ml of water to give 536 mg of product that sintered at 201° and decomposed at 204°. A second recrystallization from water, 27 ml, gave 453 mg of bright yellow needles, dec. 212°, with effervescence. | Novel nitropyrazinyl- and nitropyridinyl- substituted piperazin-3-one and hexahydro-1H-1,4-diazepin-5-one compounds are disclosed to have activity in increasing the sensitivity of hypoxic tumor cells to radiation. Also disclosed are methods of preparing such compounds and pharmaceutical compositions including such compounds. | 2 |
TECHNICAL FIELD
[0001] The present invention relates to a sewing machine which has a horizontally disposed lower bobbin with a device and a method for control of the machine so that an increase in the stitch width can be achieved as compared with conventional sewing machines of a corresponding type.
STATE OF THE ART
[0002] There are currently on the market a number of appliances with different configurations for forming lock stitches in order to produce a seam in a piece of material being sewn, said piece of material hereinafter referred to for the sake of simplicity as fabric. Ordinary domestic sewing machines conventionally involve the use of an upper thread and a lower thread on a bobbin which in cooperation with a needle causes the upper thread to execute a lock stitch in the fabric being sewn in the sewing machine.
[0003] Sewing machines of the lock stitch type have since a long time been part of the state of the art and their mode of operation is well-known. Taking, for the sake of simplicity, a sewing machine with a single needle as an example, such a machine forms stitches by the upper thread and the lower thread being linked together by the needle moving to and fro through a fabric which is moved forward across a sewing table, which is usually in a plane substantially perpendicular to the length of the needle. Most conventional sewing machines of this kind have a take-up lever which pulls the upper thread from an upper thread storage bobbin. The take-up lever provides the needle with the upper thread by an oscillating movement towards and away from the fabric. The expression “upper” hereinafter means the side of the fabric where the needle is housed. “lower” means the side of the fabric where the making of a knot is effected. Also, the expression “thread” hereinafter always means “upper thread” unless otherwise indicated.
[0004] When the take-up lever is in its highest position, a maximum amount of thread has been drawn out for the next stitch, after which the movement of the take-up lever reverses back downwards. After the take-up lever's reversal, the thread will form a loop under the fabric, since the effect of friction in the fabric will result in not all of the thread drawn out being immediately drawn back by the take-up lever.
[0005] The lower thread is unwound from a lower bobbin accommodated in a gripper under the fabric. The gripper may be of a rotating type and equipped with a gripper tip (sometimes called gripper arm) which in the course of the gripper's rotary movement hooks into the loop formed by the upper thread and in its continuing movement leads the upper thread round the lower bobbin.
[0006] When the oscillating movement of the take-up lever takes it upwards away from the fabric, the take-up lever draws surplus upper thread back, i.e. the amount of thread not consumed in the respective stitch. The thread drawn forward constituting said loop will thus be pulled tight so that a lock stitch is formed by the upper thread and the lower thread in cooperation, since the gripper has led the upper thread round the lower thread. A feeder on the sewing machine will then move the fabric forward for a subsequent stitch.
[0007] Said oscillating movements executed by the needle, the take-up lever and the gripper are mutually synchronised and are repeated cyclically for each stitch executed with the sewing machine.
[0008] Generally, a gripper system is nowadays so configured that the gripper rotates about a lower thread bobbin. A distinction may be made among gripper systems of two types, one of them with the gripper rotating in the horizontal plane, the other with the gripper rotating in the vertical plane, parallel with the needle. To achieve advantages with horizontal grippers, they have to be situated ahead of the needle, which makes it easier to reach a lower thread bobbin case in order to change the bobbin or the thread on it without having to remove the fabric from the sewing table. The gripper system used in the sewing machines referred to in this application has a horizontally disposed gripper. The gripper is provided with a bobbin basket, in which the lower thread bobbin is placed. During sewing, the bobbin remains stationary while the gripper rotates about it.
[0009] The needle directing the upper thread is fitted to the bottom of a needle rod which, synchronously with the other parts of the sewing machine involved in forming a stitch, moves the needle up and down in an oscillating movement. The needle is also allowed to move sideways synchronously with the formation of stitches. Sideways movement of the needle is necessary in the case of stitches required to have a width, i.e. to have the thread move a distance sideways across the fabric during sewing. This involves a difficulty in the case of a horizontally fitted lower bobbin, since the needle has to be adjacent to the gripper when said loop is formed if a safe capture of the loop should be rendered possible for the gripper. Accordingly, the sideways movement of the needle in the horizontal plane has to follow a slightly curved path adapted to the radius of the gripper in its rotary movement. This is readily observable on a domestic sewing machine, where a stitch plate serving as support for the fabric and at the same time covering the lower bobbin space is provided with and discloses a needle hole with a curved path, whereas the corresponding path on a sewing machine with a vertical lower bobbin is straight.
[0010] The mechanical components of the sewing machine with a horizontal lower bobbin are so arranged that the needle rod describes a movement along a conical surface, which movement is synchronised with that of the gripper. The technology for the movement of the needle in this context is known and is not further discussed here.
[0011] An example of prior art technology for a sewing machine of the type discussed herein is, as an example, described in U.S. Pat. No. 4,432,293, the content of which is hereby in its entirety incorporated in the present description.
[0012] As a consequence of the aforesaid curved path which the needle follows in the horizontal plane, it is clearly observable, on a finished stitch which has a width, that the thread follows a curved path if the sideways deviation is sufficient.
[0013] An operator intending to execute correctly positioned stitches of greater width, using a sewing machine of the kind described, therefore cannot generally achieve this on such a machine of conventional kind. Particularly, in decorative sewing or the sewing of alphabetic characters, greater stitch width would afford more potential for variation.
[0014] An object of the present invention is to propose a solution to the difficulties described above.
DESCRIPTION OF THE INVENTION
[0015] An aspect of the invention refers to a solution which allows an increase in stitch width on sewing machines with a horizontally disposed lower bobbin. When the thread moves sideways, as mentioned above, and follows the aforesaid arcuate path on an execution of a stitch, this entails a sideways shift of the needle in the conventional type of sewing machines and causes an unaesthetic result if completed stitches are of great width and especially where a plurality of wide stitches form a pattern. During the sideways shift of the needle in the arcuate path, the fabric is fed forward mechanically in the sewing (longitudinal) direction according to the stitch length setting, so that subsequent stitches applied to the fabric will be initiated and accomplished, with respect to fabric feeding, by the mechanical feeding of the machine according to stitch lengths which are valid for the stitches in their longitudinal direction. Instead, since the needle follows a curved path, an actual stitch length will be shorter because an actual stitch path projected in the longitudinal direction comprises a distance which is somewhat too short in the longitudinal direction. A discrepancy, an error, occurs between the actual longitudinal advance effected for the stitch and the vertical length of the stitch, i.e. its projection in the longitudinal direction. This is illustrated in FIG. 4 and described in more detail below. A solution to this problem, according to the invention, is to correct the error by causing the feeder to compensate the longitudinal advance of the fabric in proportion to the error. The error is based on the fact that the feeder on conventional machines cyclically feeds the length set by the machine without regard to the actual length of the stitch, which may vary, as indicated above, because of the curved path the needle follows across the fabric during performance of the stitch.
[0016] There are means for compensating the appearance of a seam for a certain width and a certain lateral position of the needle, but a remaining problem is that a pattern/seam which is compensated will still be distorted where the width/lateral position deviates from the compensation applied. No such problem arises if the device and the method according to the present invention are applied.
[0017] On a sewing machine which has a horizontally disposed lower bobbin and is also provided with a stepping motor which causes the feeder to advance the fabric according to the stitch length, the solution according to the invention comprises the stepping motor for the longitudinal feed being caused to advance the fabric at each step according to an algorithm which compensates for the abovementioned error which occurs on performing very wide stitches. The compensation here described might presumably also be achieved by a mechanical device in a sewing machine which does not have the feed powered by a stepping motor as here described. Such mechanically effected compensation is likely to be very complicated and therefore expensive, so the measure described according to the invention has great advantages. The feed error compensation described makes it possible for the total stitch width to be increased to at least 9 mm on a conventional home sewing machine without a re-structure of the complete machine.
[0018] An advantage of the device according to the invention is of course that the availability of increased stitch width on the sewing machine opens up a more wide field of application in that wider stitches can be used in decorative sewing and the sewing of alphabetic characters. Moreover, the measures according to the invention are not particularly expensive, since all that is required is that the control program for the stepping motor for the longitudinal feeder is programmed into the control program of the sewing machine and that the mechanical components affected by the possible wider stitches are adjusted to the increased stitch width, as described below.
BRIEF DESCRIPTION OF DRAWINGS
[0019] FIG. 1 depicts a schematic template drawing of a front view of a sewing machine with a horizontally positioned lower bobbin and a longitudinal feed unit indicated in the lower arm of the machine.
[0020] FIG. 2 depicts a schematic template sketch from the side of the sewing machine according to FIG. 1 , showing the take-up lever's highest and lowest positions, illustrating the travel distance and also showing a gripper with gripper tip and thread loop within the sewing table.
[0021] FIG. 3 depicts in perspective a unit for longitudinal feed of fabric in the sewing machine.
[0022] FIG. 4 depicts a sketch of the movement of the needle in a system of coordinates during the execution of a stitch.
DESCRIPTION OF EMBODIMENTS
[0023] A number of embodiments of the invention are described below with reference to the attached drawings.
[0024] By way of example of the functioning of a lock stitch sewing machine, FIG. 1 depicts symbolically a sewing machine 1 where in a conventional manner a fabric 2 is fed forward between a lower thread 3 and the upper thread 4 in order to execute a seam comprising desired stitches effected by means of a needle 5 , which moves periodically through the fabric 2 . In this example, the fabric 2 is moved across a sewing table 6 , which also accommodates a horizontally disposed lower bobbin 7 intended for the lower thread 3 and encased in a gripper 8 in a lower arm 1 a of the sewing machine. The sewing table 6 , further, has a stitchplate 6 a over which the actual seam is executed. The upper thread 4 is led via a take-up lever 9 , which by a cyclic up and down movement creates a loop 10 (symbolically indicated in FIG. 2 ) of the upper thread 4 when the needle 5 , through the eye of which the upper thread runs, has carried the upper thread through the fabric 2 and the take-up lever 9 reverses back upwards from its lowest position. A gripper tip 11 hooks into the loop 10 when the gripper 8 rotates. To execute a stitch, in this case a lock stitch, the needle 5 performs a fore and aft movement so that it leads the upper thread 4 down through the fabric 2 , after which the gripper 8 leads the upper thread 4 round the bobbin 7 , which carries the lower thread 3 , resulting in a knot in the fabric 2 when the needle 5 moves up through the fabric and the take-up lever 9 tightens the knot inside the fabric. The diagram also shows a thread magazine 15 for the upper thread. A thread tension sensor spring 14 is also indicated.
[0025] The machine is provided with a control program which is, for example, stored in a processor C. The control program conducts at least the control of a stepping motor which regulates the advance of the fabric in a longitudinal feed unit 20 .
[0026] The feed is the system which causes linear movement of the fabric between stitches in a seam. It comprises a feeder 21 , which usually has a number of parallel rods with sawlike teeth at the top and is provided with elongate apertures in the stitch plate disposed in parallel on each side of the position where the needle 5 penetrates the stitch plate, where further an arcuate hole is formed in the stitchplate 6 a for the needle 5 . The feeder 21 can be lowered so that its teeth do not appear above the stitchplate 6 a . The feeder usually performs a rotary movement whereby it moves up through the stitchplate, grips the fabric with the feeder teeth and moves forward in the longitudinal direction of the seam and thereafter down into the stitchplate and back to the initial position, after which the movement is repeated. The result is that the fabric 2 moves forward in the longitudinal direction of the seam.
[0027] A feed unit 20 of the type used in the present invention is depicted in FIG. 3 . It should be noted here that the feed mechanism depicted according to the feed unit 20 is an example to indicate one possibility for implementing the invention. Other variants of feed mechanisms might equally well be used, provided that they can be adapted to control the advance according to the aspects of the present invention. The sewing table comprises a so-called table shaft 22 which is driven by the sewing machine motor synchronously with, for example, a needle and a take-up lever. The feed unit 20 is fitted about this table shaft 22 . The movements of the feeder are effected by two excenters on the table shaft 22 . A first excenter, the height excenter 23 , adjacent to a gearwheel 24 , which drives the gripper 8 , effects the movement of the feeder 21 in the height direction. A second excenter, the longitudinal excenter 25 , arranged further inwards on the table shaft 22 , effects the movement of the feeder 21 in the longitudinal direction.
[0028] A race round the whole periphery of the height excenter 23 abuts a link 26 for height feed, which link performs an oscillating movement in the height direction when the table shaft 22 rotates. The height feed link 26 is supported on a rotation shaft 32 for a longitudinal feed arm 28 . A feeder yoke 27 to which the feeder is fastened is directly connected to the height feed link 26 by a slide screw and therefore follows the movement of the height feed link 26 in the height direction.
[0029] Similarly, there is round the whole periphery of the longitudinal excenter 25 a race, which a link 30 for longitudinal feed is adapted to abut. The longitudinal feed link 30 has its opposite end fastened to and supported by a longitudinal feed arm 28 . The longitudinal feed link 30 also has at the end where it abuts the longitudinal excenter 25 a pin supporting a block 35 , which slides in a guide 34 when the longitudinal excenter 25 moves the longitudinal feed link 30 in the height direction. The movement of the longitudinal feed link 30 is transferred to the longitudinal feed arm 28 as a feeder 21 movement a length in the longitudinal direction of the feeder 21 , wherein said length depends on the angle of the guide at the time. The result is the desired longitudinal advance of the feeder 21 , while at the same time this advance movement is synchronised with the previously described movement of the feeder 21 in the height direction.
[0030] The longitudinal feed is a parameter being possible for the user or the sewing machine's control program to determine. To this end, a stepping motor for the feed, a feed motor 33 , is adapted to and fitted in the sewing machine arm, i.e. the lower arm 1 a , and is connected to the feed device via the aforesaid block 35 . Said block 35 is connected to the previously mentioned pin and the guide 34 . Stitch length resetting is effected via the feed motor 33 . In the present example, the geometry of the feed motor 33 is so adapted that each step effected by the motor entails rotation of the motor a predetermined angle of rotation, wherein a change of said angle corresponds to a change of a corresponding predetermined feed length, by which the feeder 21 moves the fabric forward.
[0031] According to the state of the art, the stitch length is set by means of the guide 34 , which is disposed adjacent to the longitudinal feed link 30 and is also suspended about an axis of rotation so that the guide 34 can be inclined in relation to the longitudinal feed link 30 . In this example, the guide is provided with a groove, in which the block 35 can run. The block 35 , in turn, is itself connected via said pin to the longitudinal feed link 30 , whereby the block 35 is journalled on said pin. The radius of the guide 34 at the groove for the block 35 corresponds to the distance between the journal centre of the block 35 at the pin and the journal centre of the longitudinal feed link 30 at the longitudinal feed arm 28 .
[0032] When the radius of the guide coincides with the distance from the journal centre of the block 35 to the journal centre of the longitudinal feed link 30 at to the longitudinal feed arm 28 , the feed movement will be zero. Turning, i.e. rotating, the guide 34 from this position, will increase the feed. Turning of the guide 34 is accomplished by the feed motor 33 turning a gear segment 36 which is firmly connected to the guide.
[0033] Each time the sewing machine is started, the feed motor is calibrated and thereafter steps to a selected stitch length by the aforesaid angling of the guide 34 . Compensation of the stitch length error on the fabric relative to the set stitch length occurring during the previously described sideways shift of the needle 5 when the latter executes a very wide stitch can be achieved according to an aspect of the invention by increasing the working range of the mechanical feed components in the same way as described above.
[0034] An algorithm described below loaded into a control program for the feed motor 33 controls said feed motor 33 to effect longitudinal feed compensation when a longitudinal feed error is present in stitches for which the needle executes large sideways shifts.
[0035] The proposed algorithm may be used for all sewing machines which have a horizontally positioned lower bobbin and a needle movement adapted thereto.
[0036] In a mechanical platform for sewing machines having a horizontally positioned lower bobbin the needle moves in the plane of the fabric 2 sideways along an arc 40 constituting the periphery of a circle which encircles the rotation radius of the gripper tip. This is illustrated in FIG. 4 , in which the movement of the fabric caused by the longitudinal feed is indicated in a system of coordinates along a y coordinate. The needle's sideways movement is represented by the x coordinate. When the needle shifts sideways from the neutral position along the y axis to a new position in the x direction, the result is an undesired shift in the y direction relative to the fabric 2 , which undesired shift is particularly evident in the case of large shifts in the x direction. The path of the needle is represented in the diagram by a chain-dotted curve. The depiction according to the diagram also means that the desired position for the stitch entails a lateral shift along the x axis.
[0037] The following notations are used below (see FIG. 4 ):
x n Desired distance from the needle's central position in the x direction in a Cartesian system of coordinates for any desired stitch n in a stitch sequence. y n Desired distance in the y direction in a Cartesian system of coordinates for any desired stitch n from stitch n−1 preceding it in a stitch sequence. r The radius in a system of polar coordinates with its origin of coordinates at the centre of the curve which the needle's movement describes relative to the surface of the stitchplate, i.e. in the same work the curve of the intersection between the conical surface which the needle's movement follows and the stitchplate. φ n Angle in a system of polar coordinates with its origin of coordinates at the centre of the curve which the needle's movement describes relative to the surface of the stitchplate for any desired stitch n, where φ n =0 when x n =0. e n The error, i.e. undesired shift in the y direction for any desired stitch n in a stitch sequence, caused by a circular needle movement along the curve described by the needle movement.
[0043] Transformations between rectilinear Cartesian stitch data and polar coordinates also produce the relationships
[0000]
ϕ
n
=
arc
sin
(
x
n
r
)
e
n
=
r
(
cos
(
ϕ
n
)
-
1
)
[0044] The following notations:
φ n Feed motor's position for any desired stitch in a stitch sequence x 0 Initial needle position at start of pattern repeat Δ F Feed motor's resolution, in mm/step e Δ Residual error due to quantisation, in number of stepping motor steps. f n Total shift in y direction for any desired stitch n for effecting full error compensation Z(x) Function for rounding to nearest whole number N Total number of stitches in the stitch sequence for a pattern repeat can be used to write an algorithm as follows for control of the feeder 21 , wherein 1≦n≦N for a pattern repeat with the stitch coordinates {(x 1 , y 1 ), . . . , (x N , y N )}:
[0000] n=1:
[0000]
f
1
=y
1
−e
1
+e
0
[0000] Φ 1 =Z ( f 1 /Δ F )
[0000] 2≦n≦N:
[0000] e Δ =f n-1 −Φ n-1 *Δ F
[0000]
f
n
=y
n
−e
Δ
−e
n
+e
n-1
[0000] Φ n =Z ( f n /Δ F ) [1]
[0052] The theoretical background for effecting compensation is set out above. The solution is effected in practice by the software in the sewing machine's processor being adapted to cause the feed error due to the sideways needle shift to be compensated by a control of the feed motor 33 according to the above outlined algorithm. Since the feed motor in the present example takes the form of a stepping motor which makes discrete steps, account is also taken, in order to achieve the best possible results, of the error which cannot be compensated because of this limited resolution of the stepping motor. An uncompensated residual error from a stitch is saved and added to the calculated total error compensation for the next stitch for as long as error compensation is called for in a sequence of stitches, i.e. until a pattern repeat is completed, whereupon any residual error is zeroed.
[0053] As previously mentioned, the sewing machine's software is adapted to perform the calculations needed for said feed error compensation. To this end, the sewing machine is provided with a data program product programmed to do the calculations set out equation [1] above.
[0054] For compensation of the fabric feed error to be possible, the fabric feed device needs to be able to effect feed movements which extend beyond the usual range of a sewing machine which lacks the compensation described. If for example the concept of the present invention is used for an ordinary sewing machine provided with the longitudinal feed range from −6.0 mm to +6.0 mm, the maximum stitch width of the machine using the concept of the present invention can be set to 9 mm and the needle tip moves along the aforesaid arcuate path at a radius of 18.45 mm, the longitudinal feed device has to cope with a somewhat larger range than in previously known machines, in this case a stitch length range of from −6.588 mm to +6.588 mm. Some examples of this appear in the table below.
[0000]
|X n |
θ n
0.000
0.000
1.000
−0.029
2.000
−0.115
3.000
−0.259
4.000
−0.463
4.500
−0.588
[0055] If the stepping motor which constitutes the feed motor 33 is adapted to microcontrol, i.e. not making discrete feed steps, there will of course be no need to cater for residual error in a stitch. | A method and device applicable to a sewing machine which has a needle and a gripper with a horizontally positioned lower bobbin for executing a seam with stitches in a sewing material being sewn, for compensating a deficiency in a longitudinal shift of the needle during a stitch being caused by an arcuate movement of the needle when it shifts sideways in a stitch, wherein the method includes the material being advanced by a feeder a length y n in the longitudinal direction of the seam on the basis of the seam setting, and wherein the sewing machine has a control including an algorithm causing the feed motor to set the feeder, so that at each stitch which includes sideways shifts of the needle it advances the sewing material a correction length e n in the longitudinal direction of the seam, thereby compensating a corresponding deficiency in the needle's longitudinal shift relative to the material during the stitch being caused by the needle's arcuate sideways movement. | 3 |
BACKGROUND OF THE INVENTION
Cross Reference
This application is a continuation-in-part of my U.S. patent application Ser. No. 016,091, entitled Turntable System With Low Aggregate Resonance, filed on Feb. 28, 1979, and now U.S. Pat. No. 4,225,142.
I. Field of the Invention
The invention pertains generally to high fidelity turntable systems and is more particularly directed to a low aggregate resonance substructure for mounting such systems.
II. Description of the Prior Art
Turntable designers in the past have exerted much concentration on reducing acoustic distortions in high fidelity systems. Their efforts have primarily been directed to decreasing such distortions as wow and flutter, which are speed inconsistencies, or rumble, which is the basic noise level inherent in the rotating motion of a system that is received by a phonographic cartridge during play. So much success has been achieved in alleviating these two distortions that they have virtually been eliminated as problems to the serious audiophile.
One acoustic distortion problem for which much less progress has been made is resonance. This serious distortion can be described and summarized as the sounds produced by the substances of which the turntable system is constructed. Further, depending upon the acoustic and mechanical coupling of the turntable to its environment, these substances may also include the objects on which the turntable is mounted or even resting. The resonant sounds produced by these substances are created by and amplified along with the musical or other information that the phonographic cartridge is processing, thereby producing distortion. The problem usually manifests itself as a "thump" or a loss of fidelity in the lower, or even middle, frequencies and is sometimes referred to as "one note bass".
Generally, the cause of the problem is accepted as being one of feedback, as the turntable substances will not make sounds by themselves. Thus, it is the excitation of these substances by the sound itself which produces the resonance and consequent distortion.
It is believed that there are three principal feedback paths in a turntable system. The first is through the air from the acoustic energy produced by the speakers to the turntable. Energy in the form of sound vibrations excite the turntable system construction through this acoustic path to produce a resonant distortion.
The second principal path is a mechanical one whereby the mechanical vibrations of the speakers and the vibrations caused by their acoustical energy in other surrounding objects are coupled back through any solid object in contact with the mounting structure of the turntable. The closer the speaker is to the turntable system and the more direct the mechanical coupling, the more distortion this feedback path creates.
The third path which has not been previously compensated or described is an inherent feedback path where the actual sound vibrations produced by the cartridge transducing the stylus motion into electrical signals provide an excitation for the resonant substances comprising the turntable.
Generally, the prior art has attempted to solve these resonance problems by providing a very high mass structure for mounting the turntable assembly and by decoupling this high mass structure from the environment with resilient members such as springs. The high mass structure will require more acoustic energy to resonate and, thus, will alleviate the acoustic feedback while the decoupling springs will isolate the high mass structure from mechanical vibration and substantially limit the mechanical feedback.
The high mass of the turntable supporting structure, however, may exacerbate the inherent feedback as there is a greater amount of physical material present to be heard by the tone arm assembly. Further, a massive mounting structure is bulky to handle and necessitates a stronger and more expensive set of decoupling springs.
In addition, many modern amplification systems have equalization factors where lower notes are amplified more than higher notes. This is to compensate the method used for the mechanical recording medium where lower notes produce less physical movement of the stylus and, thus, less signal. Lower resonant tones will, consequently, be amplified, along with low note information, more than the higher resonant tones. It would, therefore, be highly desirable to eliminate as much of the low resonant feedback from a turntable system as possible, even to the extent of increasing the high resonant tones.
SUMMARY OF THE INVENTION
Therefore, it is a primary object of the present invention to alleviate these problems found in the prior art and more fully compensate a turntable system for all three feedback paths.
Another object of the invention is to provide a rigid, low resonance connecting substructure for the tone arm assembly and the platter assembly of a high fidelity turntable.
A further object of the present invention is to provide a tone arm assembly in which the counterweight mass is decoupled acoustically from the tone arm.
Still another object of the invention is to provide a rigid, quiet substructure which is mechanically decoupled from the mounting structure of the turntable assembly.
In accordance with the above-stated objects of the invention there is provided a turntable system having a platter assembly and tone arm assembly connected by a substructure comprising three tubular struts radially outreaching from the platter assembly rotation axis. Preferably, the tubular substructure is constructed of a material which has a high strength-to-mass ratio and is an acoustic substance. In the preferred embodiment, this acoustic substance is pure aluminum tubing which is resonant at frequencies in the high audio range with higher tonal qualities and harmonics. Such a substance is easily damped beyond its resonance point by an internal damping substance. In the implementation shown, a dense foam rubber is packed tightly inside each supporting strut for such damping.
I have found that substructures having nontubular shapes also render somewhat improved results if the substructure is internally damped. Thus, although tubular substructures represent the best results achieved to date for my invention, other forms of the invention also provide a noticeable improvement over the prior art.
In this manner, any acoustic or inherent feedback received by the low mass structure is damped by the foam rubber and the system reliably quieted by this method. The low mass substructure is also not resonant to low acoustic notes and low inherent notes and, therefore, they are not over-amplified or heard. The higher notes that would be heard without the internal damping of the supporting structure are easily dissipated by the provision of the internal damping substance.
Further, the counterweight of the tone arm assembly is acoustically decoupled by resilient means to provide more inherent feedback decoupling. The counterweight mass, if isolated from the system, will not be heard and will produce an even quieter system.
The substructure is resiliently mounted by extension springs from a base plate of a mounting cabinet to decouple the system from any mechanical or inherent feedback loop. The extension springs are more effective decouplers than compression springs due to the ability of the system to use a lower spring rate and can be further provided with internal foam rubber damping in their flexible, resonant coils. In this manner, the turntable system floats on the three struts or other shape of the substructure and all three feedback paths have been effectively damped or decoupled.
The rigid connection between the platter assembly and tone arm assembly is important for the fidelity of the reproduction of the information on the recording disk. Distortion or loss of information can be introduced into the system if the tone arm assembly, and, thus, the cartridge, moves in a dissimilar mode to the platter assembly or recorded information. The present substructure, therefore, provides a rigid connection necessary for coupling these assemblies without introducing resonant distortion.
These and other objects, features, and advantages of the invention will be clearer and more fully understood from a reading of the detailed description when taken in conjunction with the appended drawings wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of the preferred embodiment of a turntable system constructed in accordance with the invention;
FIG. 2 is a longitudinal cross-sectional side view along section line 2--2 of FIG. 1;
FIG. 3 is a cross-sectional end view along section line 3--3 of FIG. 1;
FIG. 4 is a fragmentary perspective view of a typical suspension mounting for the system illustrated in FIG. 1;
FIG. 5 is a cross-sectional view along section line 5--5 of the counterweight illustrated in FIG. 2; and
FIG. 6 is a perspective view of an alternate internally damped substructure according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 and 2, there is shown a high fidelity turntable system comprising a tone arm assembly 6 and platter assembly 4 rigidly connected by a substructure 8. The tone arm assembly 6, which has a phonographic cartridge 9 cantilevered on the tone arm 10 and balanced by a counterweight 38, is for providing an electrical signal representative of the mechanical motion of a stylus on a recording surface, as is conventional in the art. The electrical signals pass through connecting wires from the cartridge to a connector 15 and may be then transmitted to an amplifier. Preferably, tone arm assembly 6 is commercially available as a SME Model 3009, Series III.
A mounting pillar 17 is upwardly standing in a rectangular plate 19 which is balanced on a pair of U-shaped mounting members 14 and 14', respectively. Each of the mounting members 14, 14' (as better seen in FIG. 3) are tubular and bent into the U-shape by suitable means to form two arms which have affixed at each end a mounting block 12, 12' which are adapted to receive screws through drilled apertures in the rectangular base plate 19. Grommets 2, 2' are inserted in the apertures between the plate and screws to break one part of the feedback path between the base plate and the substructure by sitting on the mounting blocks and isolating the connecting structure from the U-shaped mounting members.
Each of the U-shaped mounting members, 14, 14', are connected to a main tubular support strut 20 by means of a single metal screw 21, and conventionally fixed by a nut.
The main tubular support strut 20 extends to a point beneath the platter assembly 4 where it is connected to a disk-shaped plate 25, preferably with two small metal screws. The plate 25 also has mounted, in a similar manner by two small screws, tubular struts 24, 24' which connect at an angle to provide an equiangular mounting structure. The three struts are equal angularly provided as radial extensions from the rotational axis of the platter assembly 4 for balance and support, with the least number of elements.
The struts are preferably constructed of an acoustic material that has a very high strength-to-mass ratio so they may provide a low resonance structure with adequate structural support. The struts, being tubular, are closed upon themselves and have no open vibratory surfaces. Thus, vibrations will be transmitted along the longitudinal axis of the strut. Each tubular strut is provided with an internal damping 64 (see FIG. 4), preferably dense foam rubber, that will quickly dissipate vibrations and resonances that are excited in the material. In this implementation, very pure aluminum tubing is utilized, and the high tonal qualities and harmonics that might be excited and transmitted in this substance are easily damped out and not heard by the tone arm. Thus, a rigid substructure that has a low aggregate resonance has been shown in accordance with one of the objects of the invention.
Each tubular strut is isolated from the mechanical and inherent feedback path by an extension spring 34, 36, 33 (see, for example spring 34 in FIG. 4). The struts are decoupled from a base plate 37 by hooking one end of the extension spring 34 over an eyelet 35 screwed into the plate, and the other end of the spring through a drilled hole in the end of the tubular strut 20. The base plate 37 mounts in a peripheral ridge in a mounting cabinet 32 to allow the system to float free of mechanical disturbances.
Because of the lower mass and resonance of the substructure 8, less resilient springs must be used. Also, the springs can be provided as extension rather than compression springs which will produce even more effective decoupling of the mechanical feedback path. A natural oscillation frequency of approximately 2-3 Hz. will produce the most effective decoupling and the springs may further be damped internally with a dense foam rubber material.
The lower the frequency of the oscillation of the mass and spring combination, the greater will be the decoupling. The decoupling is effective when between the natural frequencies of the platter assembly and the tone arm assembly which are generally 8 Hz. and 1.5 Hz., respectively.
FIG. 6 depicts a substructure 65 alternative to the tubing depicted in FIGS. 1-4. The substructure 65 is shown in the form of an inwardly tapered triangle, but other shapes are suitable for the invention so long as the overall mass of the substructure is maintained at a minimum and the substructure is formed of a suitable material as outlined above.
Substructure 65 is formed of two plates, preferably very pure aluminum plates, 66 and 68. Sandwiched at several positions between the plates 66 and 68 are damping materials, preferably dense, foam rubber. Such damping materials are shown at 70 and in the broken section at 72 near the inner central portion between plates 66 and 68. Drilled holes 74 are provided at the corner portions of substructure 65 for attachment of extension springs 33, 34, 36 in the same manner as for the tubular struts. Although the substructure 65 is shown in FIG. 6 as open along its outside edges, it is also possible to form substructure 65 as a sealed low mass-to-strength ratio component with dense foam rubber damping positioned therein.
The extension springs 33, 34 and 36 are used to suspend the substructure 65 from the base plate 37 in the same fashion as the tubing 20 is suspended from the base plate in FIG. 4. The platter 4 (FIG. 2) is mounted in a central hole 80 of the substructure 65 while the tone arm assembly 6 (FIG. 2) is mounted to a rectangular hole 82 in the substructure 65.
Substructures in the form of parallel plates or other shapes and as depicted in FIG. 6 have also proved to be a suitable improvement over the prior art by effectively damping or decoupling the three feedback paths associated with excitation of the turntable substances by the sound system. It should also be understood that the invention is not limited to two plates or two members as depicted in FIG. 6. For example, the depiction in FIG. 6 may be formed as one piece with connecting walls between plates 66 and 68, it being understood that this is the equivalent of the two members 66 and 68 depicted in FIG. 6. Similarly, other shapes having one member with an internal space or two or more members with spaces therebetween are suitable equivalents so long as they are properly damped according to the invention.
The platter assembly 4 is positioned on the top side of the disk-shaped plate 25 by three hexagonally headed mounting bolts 30. The connection is isolated from the substructure by wrapping dense foam rubber 22, 22' around the mounting screws 30. In this manner, the screws 30 are not allowed to touch the platter assembly 4. This creates a mild but effective acoustic barrier for the transmission of vibration through the system and quiets part of the inherent feedback path. The hexagonal heads on the screws 30 are used to facilitate balancing and leveling the mounting with a wrench once the platter is assembled and placed in position.
The platter assembly 4 comprises the disk-shaped plate 25 screwed to a mounting plate 26 having an upwardly standing spindle 64 which has a bearing assembly for mounting a drive wheel 42, onto which a disk-shaped platter 44 may be placed. The platter assembly 4 sans the disk plate 25 was a component of an ERA MK6C Turntable.
The drive wheel 42 is operably driven by a flexible belt 41 that is slipped over the drive shaft of a vertically mounted motor 62 on an acoustic base 43. The motor 62 may be provided with suitable drive controls via connector 60. The flexibility of the drive belt 41 contributes to the reduction in resonance and noise, as vibrations from the motor are not transmitted readily through the elastic medium to the platter assembly. The drive pulley fitted on the shaft of the motor 62 is supplied with two differently sized tracks so that the drive belt 41 may be moved into either track depending on the speed selected for the recording.
When the platter 44 is removed, the substructure 8 will be lifted upward by the extension springs 33, 34, 36 on which it is suspended, and C-shaped holding blocks 50 and 52 are provided cross-wise to the radial struts to limit this movement. Likewise, a transverse bar 56 limits the upward movement of the main support strut 20. All the limiting structures 50, 52 and 56 can be equipped with small pads where they contact the struts of the substructure to prevent damage thereto.
Turning now to FIG. 5, in accordance with one of the objects of the invention, the counterweight for the tone arm has been decoupled acoustically from the mass of the turntable system by a pair of extension springs 40 and 40'. The counterweight 38, as preferably shown, is a cylindrically-shaped weight of the adequate mass to balance the tone arm 10 and provide the correct tracking pressure on a recording surface. The counterweight 38 is center-bored and has extension springs 40, 40' extending through two radial apertures to attach at one end to a dowel 39 located transversely within the center bore. The other ends of the extension springs 40, 40' attach over the finger-like projections of the tone arm to apply the counterbalancing force. In this manner the force of the counterweight 38 is apparent to the tone arm assembly 6 to provide the correct tracking pressure, but its mass is not heard by the system.
While the preferred embodiments of the invention have been shown, it will be obvious to those skilled in the art that modifications and changes may be made to the disclosed system without departing from the spirit and scope of the invention as defined by the appended claims. | A high fidelity turntable system with low aggregate resonance is disclosed. The turntable system comprises a tone arm assembly and a belt-driven platter assembly joined rigidly by a silent substructure of pure aluminum tubing and other shapes. This low acoustic mass substructure is internally damped beyond its resonance point and is resiliently suspended from a base plate in a mounting cabinet to isolate the turntable system for substantially all resonant feedback. The acoustic mass of the turntable system and, consequently, the resonance, is further reduced by decoupling the tone arm counterweight from the tone arm assembly by means of additional resilient elements. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a coating device and a tool used in the coating device, and more particularly to a coating device and a tool for coating an optical film thereon with a precise gradually changed slope and gradually changed area.
[0003] 2. Description of the Related Art
[0004] In film-coating filed, coating a film with more than two kinds of thickness on a substrate, in particular, with a specific gradually changed slope, is difficult.
[0005] Conventional methods for coating a film with more than two different thickness in different sections on the same substrate are implemented by regulating the oblique angle of the substrate or using an assistant board during the coating process. Consequently, the thickness of the coating material on the substrate is different on different areas of the substrate. Thus, an optical film with various gradually changed effects is formed by changing the thickness of the film to thereby change the spectrum characteristic of the film. However, the thickness of the coating material cannot be precisely controlled by the above-mentioned methods.
[0006] FIG. 1 is a schematic view of a conventional coating device 5 . The coating device 5 comprises a base 52 and a substrate 51 obliquely set above and spaced from the base 52 . A target 53 is placed on the base 52 for forming a coating film 54 on the substrate 51 by sputtering or vapor-depositing. The substrate 51 is arranged at an oblique angle with respect to the base 52 . The thickness of the coating film 54 is in an inverse proportion to the 1.5 th to 1.9 th order of the distance between the base 52 and the substrate 51 . Therefore, the closer a portion of the substrate 51 is to the base 52 , the larger the thickness at the portion of the coating film 54 is.
[0007] Although the oblique angle between the substrate 51 and the base 52 creates the coating film 54 having a gradually changed thickness on the substrate 51 , a gradually changed slope at a specific point on the substrate 51 cannot be defined. When the substrate 51 is tilted at an angle with respected to the base 52 , the gradient slope is pre-determined and the coating film 54 with the desired specific gradually changed slope is prohibited.
[0008] FIG. 2 shows another typical coating device 9 using an assistant board with different shape. The coating device 9 comprises a vacuum chamber 90 , a coating umbrella 91 fixed on an upper portion of the vacuum chamber 90 , an assistant board 92 , and a coating material source 93 . The coating umbrella 91 is pivotally fixed with an axis of a motor 94 and is drove by the motor 94 to rotate about the axis. The coating material source 93 is located opposite to the coating umbrella 91 . The assistant board 92 is located adjacent to the coating umbrella 91 and between the coating material source 93 and the coating umbrella 91 . The coating umbrella 91 has a plurality of coating holes (not shown) in which a plurality of substrates 95 is fixed and a fix hole 910 receiving the axis of the motor 94 . The shape of the assistant board 92 and its position on the coating umbrella 91 will determine the thickness of the film on the substrate 95 . The detailed structure of the coating device 9 can be referred to Taiwan Patent Publication No. 540585.
[0009] During the coating process using the coating device 9 , the plurality of substrates 95 are fixed on the coating umbrella 91 . The motor 94 then drives the coating umbrella 91 to rotate and the coating material source 93 sputters or vapor-deposits coating material on the substrate 95 . After the substrates 95 each are coated with one or more layers of coating material, the substrates 95 are detached from the coating umbrella 91 and other substrates 95 are put in the vacuum chamber 90 . Because there is a long distance between the assistant board 92 and the substrate 95 , it is difficult to precisely control the thickness of the coating on the substrate 95 .
[0010] Taiwan Patent Publication No. M249958 disclosed another coating device. The coating device includes at least two coating material sources and at least two corresponding assistant boards. Similar to the device discussed above with reference to FIG. 2 , it is also difficult for this coating device to precisely control the film with the gradually changed slope and the gradually changed area.
SUMMARY OF THE INVENTION
[0011] Thus, an object of the present invention is to provide a coating device and a tool used in the coating device, the coating device can form a film which gradually changed slope and gradually changed area are precisely controlled.
[0012] In order to achieve the above-mentioned object, the coating device in accordance with the present invention comprises a coating material source that supplies a coating material, and a substrate opposite to the coating material source. The substrate has a coating surface, which receives the coating material to form a film thereon. A board having predetermined height and thickness is arranged between the coating surface of the substrate and the coating material source. The board is rotatable with respect to the coating surface to selectively set an included angle between the board and the coating surface. By changing the height and thickness of the board and the included angle, the film is formed with a gradually changed slope and a gradually changed area.
[0013] The substrate is arranged to be rotatable about an axis. A coating umbrella is rotatable about the axis and defines a hole for receiving and fixing the substrate therein. The substrate is surrounded by a frame having opposite sides between which the board is rotatably mounted. The coating device further comprises a vacuum chamber in an upper portion of which the coating umbrella is arranged, and the coating umbrella is coupled to and driven by a motor to rotate about the axis.
[0014] The present invention also provides a tool used in the coating device. The tool comprises a frame adapted to receive and removably retain a substrate therein with a coating surface of the substrate receiving a coating material from a coating material source to form a film thereon; and a board having a height and thickness adjustably mounted on the frame and between the coating surface of the substrate and the coating material source, whereby by changing the height and thickness of the board and an included angle between the board and the coating surface, the film is formed with a gradually changed slope and a gradually changed area.
[0015] The gradually changed slope and area of the film are precisely controlled by the coating device according to the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic view showing a conventional coating device;
[0017] FIG. 2 is a schematic view showing another conventional coating device;
[0018] FIG. 3 is a schematic view of a coating device according to a preferred embodiment of the invention;
[0019] FIG. 4 is a schematic view of a tool used in the coating device shown in FIG. 3 ; and
[0020] FIG. 5 is a schematic view of a tool according to a second preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] It will be understood that the illustration is for the purpose of describing preferred embodiments of the invention and is not intended to limit the invention thereto.
[0022] Referring to FIG. 3 , a coating device constructed in accordance with the present invention comprises a vacuum chamber 10 , which can be evacuated by a vacuum pump, a coating umbrella 11 fixed in an upper portion of the vacuum chamber 10 , a plurality of tools 2 (only one shown in the drawings) installed on the coating umbrella 11 , and a coating material source 13 arranged in a lower portion of the vacuum chamber 10 .
[0023] The coating umbrella 11 is coupled to and driven by a motor 14 to rotate about an axis that is shown in dashed line in FIG. 3 . The coating material source 93 is located opposite to the coating umbrella 11 and preferably offsets from a vertical center line of the coating umbrella 11 , which can be coincident with the rotation axis of the umbrella 11 . The coating umbrella 11 forms a plurality of coating holes (not shown) for fixing the tools 2 therein, respectively.
[0024] Referring to FIG. 4 , the tool 2 is constructed to receive and retain a rectangular substrate 23 therein. The substrate 23 has a surface 231 , which will be referred to as “coating surface” hereinafter, to receive a coating material from the coating material source 13 to form a film thereon. The tool 2 comprises a frame 21 surrounding the substrate 23 . In the embodiment illustrated, the frame 12 is rectangular, corresponding to the rectangular shape of the substrate 23 . A board 22 is mounted to the frame 21 , and preferably straddling between opposite sides of the frame 21 and opposing the coating surface 231 of the substrate 23 . The board 22 is allowed to rotate with respect to the frame 21 . The board 22 has predetermined height and thickness and is inclined with respect to the frame. 21 and the substrate 23 at a predetermined oblique angle that is denoted by symbol “θ” in FIG. 4 .
[0025] The tool 2 is mounted on the coating umbrella 11 in such a way that the substrate 23 is located on an outer surface of the coating umbrella 11 and that the board 22 partially extends through the coating hole of the coating umbrella 11 and into an interior of the coating umbrella 11 . Thus, the coating surface 231 of the substrate 23 faces the coating material source 13 through the coating hole. The coating material emitted from the coating material source 13 travels through the coating hole of the coating umbrella 11 and reaches and deposits on the coating surface 231 of the substrate 23 to form the coating film.
[0026] During the coating process, the motor 14 rotates the coating umbrella 11 , while the coating material source 13 emits the coating material that is sputtered onto or vapor-deposited onto the coating surface 231 of the substrate 23 in a vacuum. After the coating surface 231 is coated with one or more layers of coating material, which form the coating film, the tool 2 is detached from the coating umbrella and removed out of the vacuum chamber 10 . Other sets of tools retaining new substrates 23 are put in the vacuum chamber 10 for the next cycle of coating operation.
[0027] Because the distance between the board 22 and the substrate 23 is short, the thickness of the film on the substrate 23 can be precisely controlled by the board 22 . The height and thickness of the board 22 and the included angle between the board 22 and the substrate 23 are selected to precisely control the amount of the coating material adhered to the substrate 23 and thus the thickness at different areas of the film formed on the substrate 23 . This will be further described. Thus, the optical film with different gradually change effects can be formed by changing the thickness of the film to thereby change the spectrum characteristic of the film. Due to the board 22 of the tool 2 , the coating material emitted from different positions of the coating material source 23 forms different amount of the coating on the coating surface 231 , thus the thickness of the coating film on the substrate 23 gradually changes. Furthermore, the substrate 23 has a movement relative to the coating material source 13 when the coating umbrella 11 rotates, so the gradually changed area of the film is increased, and the gradually changed slope is altered. Therefore, to precisely control the gradually changed slope and the gradually changed area, the tool must be designed according to specific parameters, such as the gradually changed slope and gradually changed area of the film.
[0028] The height and thickness of the board 22 and angle between the board 22 and the substrate 23 influence the gradually changed slope and gradually changed area of the coating film on the substrate 23 and are described as follows:
[0000] 1. Height of the Board 22 (H)
[0029] The greater the height of the board 22 is, the larger the gradually changed area is. The smaller the height of the board 22 is, the less the gradually changed area is. The height of the board 22 also influences the gradually changed slope.
H=K·D
where “K” is a constant determined by the material of the coating material source, curvature of the coating umbrella 11 , and parameters of the vaporization and “D” represents the gradually changed area.
2. Angle Between the Board 22 and the Substrate 23 (θ)
[0030] The angle between the board 22 and the substrate 23 is an angle from 0° to 180°. It is preferred that the angle is selected from the range between 45° to 135°. For the board 22 of a given height, the larger the absolute value of the difference |90−θ| is, the larger the gradually changed area is. For instance, assuming the height of the board 22 is 22 mm, when θ=90°, the gradually changed area is 6.3 mm, and when θ=70°, the gradually changed area is 8.5 mm.
[0031] 3. The thickness of the board 22 influences the area without film. The larger the thickness of the board 22 is, the larger the area without film is.
[0032] 4. The substrate 23 located on different circles of the coating umbrella 11 has different angles with respect to the coating material source 13 . Thus, the height of the board 22 and the angle between the board 22 and the substrate 23 should be properly designed to achieve the substrates having the same gradually changed area and gradually changed slope.
[0033] Thus, considering all of the above-mentioned factors, a gradually changed film with predetermined gradually changed slope and area can be designed. The gradually changed slope and area are precisely controlled.
[0034] Referring to FIG. 5 , a tool 3 according to a second preferred embodiment comprises a rectangular substrate 33 . The substrate 33 has a coating surface 331 adapted to receive coating material from the coating material source to form a film thereon. A frame 31 surrounds the substrate 33 along four sides thereof. A number of parallel boards 32 are mounted to the frame 31 , straddling between opposite sides of the frame 31 . The boards 32 are rotatable relative to the frame 31 . The board 32 locates on the coating surface 331 of the substrate 33 . The board 32 has predetermined height, thickness, and angle with respect to the substrate 23 .
[0035] Thus, similar to the illustration with reference to the first embodiment, by changing the angular position of each board 32 with respect to the substrate, the film formed of the coating material on the coating surface 331 can be regulated. Further, by setting the height and thickness of each board 32 , the film can also be regulated. | A coating device includes a coating material source, and at least one substrate disposed opposite to the coating material source. The substrate has a coating surface that receives coating material from the coating material source to form a film thereon. A board is disposed on the coating surface of the substrate. The height and thickness of the board and the angle between the board and the substrate determines gradually changed slope and gradually changed area of the film on the board, whereby the slope and the area can be precisely controlled during the deposition process. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The following copending applications, Attorney Docket Number 20041782-US-NP, U.S. application Ser. No. ______, filed Aug. 26, 2005, titled “Reverse Bidding for Trip Services”, Attorney Docket Number 20041784-US-NP, U.S. application Ser. No. ______, filed Aug. 26, 2005, titled “System to Manage Advertising and Coupon Presentation in Vehicles”, and Attorney Docket Number 20041785-US-NP, U.S. application Ser. No. ______, filed Aug. 26, 2005, titled “Vehicle Network Advertising System”, are assigned to the same assignee of the present application. The entire disclosures of these copending applications are totally incorporated herein by reference in their entirety.
INCORPORATION BY REFERENCE
[0002] The following U.S. patent publications are fully incorporated herein by reference: U.S. Publication No. 2001/0042038 to Phatak (“Method and System for Conducting an Auction for Resources”); U.S. Publication No. 2002/0032035 to Teshima (“Apparatus and Method for Delivery of Advertisement Information to Mobile Units”); U.S. Publication No. 2002/0194061 to Himmel et al. (“Method and System for Request Based Advertising on a Mobile Phone”); U.S. Publication No. 2003/0003929 to Himmel et al. (“Method and System for Schedule Based Advertising on a Mobile Phone”); and U.S. Publication No. 2004/0215526 to Luo et al. (“Interactive Shopping and Selling Via a Wireless Network”).
BACKGROUND
[0003] This disclosure relates generally to the advertisement of goods and services to mobile units and more specifically to certification of advertisers for propagation to mobile units on an ad hoc network.
[0004] Traditionally, roadside billboards have acted as a means for advertising goods and services to travelers, including drivers, walkers, and bikers. This advertising outlet has been frequently used by restaurants, automobile dealers, convenience stores, hotels, hospitals, and other service industries and manufacturers to provide information on services or goods available, as well as the location of the advertiser. These businesses depend on customers responding to roadside advertising or observing the business in close proximity to the roadway. The advent of on-board navigation systems makes it possible for travelers to access databases describing services many miles ahead, and consequently travelers can plan better use of roadside services. However, on board navigation also enables drivers to navigate short distances away from the main route to visit services, but this flexibility is not currently being well exploited. While it would be useful to have a method in which service businesses can interact with on board navigation systems and offer discounts, service-time guarantees, and better quality services, to induce travelers to choose their services, and in many cases to induce travelers to change their timing or venture further from their original planned routes to visit these services, to insure that the advertising received in the vehicle is limited to material of interest to the driver.
BRIEF SUMMARY
[0005] The disclosed embodiments provide examples of improved solutions to the problems noted in the above Background discussion and the art cited therein. There is shown in these examples an improved method for propagating advertisement for market controlled presentation among communication devices over a communication network accessed by service providers and an advertising service. The method is stored and executed as an application for use by network devices. The method includes receiving advertising requests and bids from potential advertisers, with each bid including a presentation slot specification and a proposed amount of payment for presentation. Ranking information is computed from the bid, with the ranking reflecting the financial value of propagation of the advertising request to the advertising service. The method also provides certification of the advertising request, with certification including a signature of the contents of the advertising request, the requested presentation slot, and the ranking information. The certified advertisement is then propagated over the communication network.
[0006] In another embodiment there is provided a system for propagating advertisement for market controlled presentation among communication devices over a communication network accessed by service providers and an advertising service, with the system stored and executed as an application for use by network devices. The system includes an advertising input module for receiving advertising requests from an advertiser and bids associated with the advertising requests. An advertisement authentication and encryption module encrypts the advertising request with an advertiser identification key. Central advertisement management and accounting module provides certification of the advertising requests. The certified advertising requests are distributed to a selected vehicle population under a predetermined policy by an advertising propagation module. For billing purposes, a transaction accounting and management module receives response records from participating vehicles in the network and transmits the response records to the central advertisement management and accounting module.
[0007] In yet another embodiment there is disclosed a system for propagating advertisement for market controlled presentation among communication devices over a communication network accessed by service providers and an advertising service. The system is stored and executed as an application for use by network devices. The system includes the capability for receiving advertising requests from advertisers, with each advertising request including bids from the advertiser for each advertising request submitted. The bid may include one or more presentation slot specifications and a proposed amount of payment for presentation. The system also includes capability for computing ranking information from the submitted bids, with the ranking reflecting the financial value of propagation of an advertising request to the advertising service. Certification is provided for the advertising requests, with certification including a signature of the contents of the certification request and the ranking information. Only certified advertising requests may be propagated over the communication network.
[0008] In yet another embodiment, there is disclosed a computer-readable storage medium having computer readable program code embodied in the medium causing the computer to perform method steps for reverse bidding of trip services among mobile communication devices over a communication network accessed by service providers and an advertising service. The method is stored and executed as an application for use by network devices. The method includes receiving advertising requests and bids from potential advertisers, with each bid including a presentation slot specification and a proposed amount of payment for presentation. Ranking information is computed from the bid, with the ranking reflecting the financial value of propagation of the advertising request to the advertising service. The method also provides certification of the advertising request, with certification including a signature of the contents of the advertising request, the requested presentation slot, and the ranking information. The certified advertisement is then propagated over the communication network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The foregoing and other features of the embodiments described herein will be apparent and easily understood from a further reading of the specification, claims and by reference to the accompanying drawings in which:
[0010] FIG. 1 illustrates an example embodiment of the system for propagating advertisements for market controlled presentation in an ad hoc advertising network;
[0011] FIG. 2 illustrates an example embodiment of the computing architecture for a system for propagating advertisements for market controlled presentation;
[0012] FIG. 3 is a flowchart illustrating an embodiment of the method for advertisement propagation in mobile vehicles;
[0013] FIG. 4 is a flowchart illustrating another embodiment of the method for advertisement propagation in mobile vehicles;
[0014] FIG. 5 is a flowchart illustrating an embodiment of the method for advertisement propagation in mobile vehicles in which the advertiser initiates propagation; and
[0015] FIG. 6 is a flowchart illustrating an embodiment of the method for advertisement propagation in mobile vehicles in which a response record is included.
DETAILED DESCRIPTION
[0016] The method and system described herein deliver advertising and coupons to vehicles using a mobile ad hoc network. The advertising is highly restricted, and may only be presented during certain “presentation slots” in vehicles. An economic mechanism such as an auction is used to choose which advertisements among competing advertisements will be delivered during the presentation slots. Advertising based on presentation slots and auctions is described more fully in Attorney Docket Number 20041784-US-NP, U.S. application Ser. No. ______, filed Aug. 26, 2005, titled “System to Manage Advertising and Coupon Presentation in Vehicles”. Rather than relying on an on-line connection to an advertising server, the discussion below is directed with implementing such a system in a network that relies on ad hoc propagation of advertising.
[0017] A market-based presentation slot advertising system for delivery of advertising and coupons to vehicles using a mobile ad hoc network has several challenges. Among them is the necessity of preventing arbitrary advertisers from flooding the propagation network with useless advertisements. It also would be useful to enable vehicles to choose the most desired advertisement according to a market mechanism and to complete the transaction and charging the advertiser for a successful presentation without an on-line connection to an advertising service. The system and method described herein accomplish these objectives through use of a certification record and a response record.
[0018] In the following description numerous specific details are set forth in order to provide a thorough understanding of the system and method. It would be apparent, however, to one skilled in the art to practice the system and method without such specific details. In other instances, specific implementation details have not been shown in detail in order not to unnecessarily obscure the present invention. Referring to FIG. 1 , the schematic diagram illustrates an example embodiment of the system for propagating advertisements for market-controlled presentation in an ad hoc advertising network. Before an advertiser can launch an advertisement into the propagation network 130 , the advertiser 120 must contact an advertising service 110 and obtain a certification record that both authorizes propagation of the advertisement and encodes information that can be used to rank the advertisement with competing advertisements. The advertisement presented to the advertising system by the advertiser 120 may be in the form of text or image and could include special offers, such as coupons or discounts. The advertiser also may present a bid to the system. The details of the bid may depend on the economic mechanism that is used, but would usually specify a ‘presentation slot’, and some indication of what the advertiser will pay for a successful advertisement presentation. A presentation slot consists of a particular circumstance for which advertisements may be presented to a vehicle user. For example, an advertiser might bid on the “low gas warning” presentation slot, bidding $0.50, indicating that it will pay one dollar when a driver responds to the ad by driving to the gas station. The text of the advertisement may be “Unleaded regular gas $1.80, after a $0.20/gallon discount to the recipient if this message, use exit 25 .”
[0019] When advertising service 110 certifies the advertisement, part of the certification may be a signature of the contents of the certification request, including such things as content of the advertisement and the presentation slot that is requested. This signature protects the advertisement from tampering when it is in transit to the vehicle. The certification also includes ranking information that is computed from the bid. So, in the case of the gasoline example, the ranking information may be the bid itself, in this case $0.50. This corresponds to a simple auction, where slots are awarded to the advertisers that are willing to pay the most per response. More complex auctions may rank bidders according to an estimate of the revenue, that is, the product of the probability of response with the amount bid. In such an auction, the advertiser would compute this estimate and include it in the certification record. One purpose of the certification step is to insure that only reasonable effective advertisements are propagated in the network. For this reason, the advertising service will likely certify advertisements for a limited period of time, and observe the rate of response to the advertisements. If this rate drops, then the advertising service can refuse to certify the advertisement, or in the case of more complex auctions, adjust the ranking so the advertisement is less likely to be presented.
[0020] Propagation of the advertisement through network 130 is governed by targeting information that is supplied by the advertiser, and by the geography and traffic loads that the advertisement encounters as it is propagated. For example, in the case of the gasoline advertisement, the advertiser may wish to target only the southbound lanes of a nearby highway, and northwards for five miles or until 250 vehicles are reached. Vehicle condition and environmental information are used to govern the presentation of the advertisement and advertisers can be charged by verified successful presentation. For instance, sensors in a vehicle sense a low gas level. All advertisements available in the vehicle that have requested presentation in the “low gas warning” slot are ranked, and the top ranking advertisements are presented to the driver at the time of the warning. If driver 140 responds to an advertisement by either selecting the advertisement to obtain more information or driving to the place of business described in the advertisement, then a response record is generated and propagated back to advertising service 110 . When advertising service 110 receives a response record, it allows the advertising service to charge for the advertisements. Together, the certification record and the response record allow the vehicle to implement market-based presentation slot advertising without an online connection.
[0021] Various computing environments may incorporate capabilities for supporting an intelligent transportation network. The following discussion is intended to provide a brief, general description of suitable computing environments in which the method and system may be implemented. Although not required, the method and system will be described in the general context of computer-executable instructions, such as program modules, being executed by a single computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the method and system may be practiced with other computer system configurations, including hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, networked PCs, minicomputers, mainframe computers, and the like.
[0022] The method and system may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communication network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
[0023] Turning now to FIG. 2 , one embodiment of a computing architecture for a system for propagating advertisements for market-controlled presentation is illustrated. Here, ad input module 210 receives a proposed advertisement, which may be in the form of text or image and may include special offers, such as discounts or coupons. The advertiser also presents a bid, which usually specifies a presentation slot and an indication of what the advertiser will pay for a successful ad presentation. The advertiser may also provide targeting information, which will be utilized in propagation of the ad in a vehicle network. Ad authentication and encryption module 220 encrypts the input data with the client key and sends the input data with client key and authenticates the advertisement request to ensure that it has been submitted from a legitimate client of the advertising service. The encrypted information is provided to central ad management and accounting module 230 , which validates and certifies the input (including advertisement content and requested presentation slots with bids), reviews the ad content and requested presentation slot and provides a ranking computed from the bid. The certified ad is then sent to ad propagation module 240 . Central ad management and accounting module 230 also stores the certified ad in a database, tracks the response records associated with specific ads and bills the advertiser for successful ad presentation. Ad propagation module 240 distributes the certified ad to a selected vehicle population, which is determined by targeting information supplied by the advertiser and by geography and traffic loads. Transaction accounting and management module 250 receives response records from participating vehicles in the network and also sends the data to central ad management module for billing purposes.
[0024] To illustrate this, a participating restaurant manager may submit a coupon for a 20% discount with an instruction to propagate the coupon within two miles of the restaurant with an agreement to pay $0.10 for each successful referral (e.g. visual presentation or cashing of the coupon). Authentication module 220 encrypts the data with the restaurant identification information and sends it to ad management module 230 . Ad management module 230 finds that the expected profit from this coupon is higher that the offer from those of other restaurants in the area and decides to deliver the coupon into the network (through ad propagation module 240 ) with higher priority. The area of propagation may be slightly reduced to a 1.5 mile radius due to historical knowledge that the successful acceptance rate beyond a radius of 1.5 mile is low and also that other coupons could more effectively use the advertising space in those areas. Some drivers in the targeted area pick up the coupon and drive to the restaurant for dinner. The drive to events are recorded by transaction management module 250 and are sent to ad management module 230 later for the purpose of billing support.
[0025] Turning now to FIG. 3 , the flowchart illustrates an embodiment of the method for advertisement propagation in mobile vehicles. Client ad input is received at 310 and will include not only the image, text, or special offers of the ad, but also a bid specifying a presentation slot and an indication of what the advertiser will pay for a successful presentation. This information, which may be encrypted, is transmitted to the ad server at 320 , which certifies the ad and ranking information at 330 . Part of the certification is a signature of the contents of the certification request, including such items as content of the advertisement and the presentation slot that is requested. This signature protects the advertisement from tampering when it is in transit to a vehicle. The certification also includes ranking information that is computed from the bid to establish a priority among bidders. The certification may be effective for a limited period of time or may be limited by the rate of response to the advertisement. The certified ad is propagated to the vehicle network at 340 under a predetermined policy developed from targeting information supplied by the advertiser, and by geography and traffic loads that the advertisement encounters as it is propagated. Vehicle condition and environmental information may also be used to govern the presentation of the advertisement.
[0026] Turning now to FIG. 4 , the flowchart illustrates another embodiment of the method for advertisement propagation in mobile vehicles. At 410 client ad input is received, as in item 310 in FIG. 3 . At 420 the ad is encrypted and sent to the ad server. At 430 the server decrypts and authenticates the ad to ensure that only ads from legitimate clients are accepted for presentation on the network. The authenticated ad is stored in a database, certified, and sent to the vehicle network at 440 . At 450 the ad is propagated through the vehicle network as described in FIG. 3 at 340 .
[0027] Turning now to FIG. 5 , the flowchart illustrates an embodiment of the method for advertisement propagation in mobile vehicles in which the advertiser initiates propagation. Client ad input is received at 510 and will include not only the image, text, or special offers of the ad, but also a bid specifying a presentation slot and an indication of what the advertiser will pay for a successful presentation. This information, which may be encrypted, is transmitted to the ad server at 520 , which certifies the ad and ranking information at 530 . Part of the certification is a signature of the contents of the certification request, including such items as content of the advertisement and the presentation slot that is requested. This signature protects the advertisement from tampering when it is in transit to a vehicle. The certification also includes ranking information that is computed from the bid to establish a priority among bidders. The certification may be effective for a limited period of time or may be limited by the rate of response to the advertisement. The certified ad is returned to the advertising client at 540 . At 550 the client may choose target area(s) and time of delivery before propagating the certified ad to the vehicle network under a predetermined or combined policy. In this case the targeting selections may not be changed after certification. Alternatively, the client may determine the scope and time of delivery after certification.
[0028] Turning now to FIG. 6 , a flowchart illustrates an embodiment of the method for advertisement propagation in mobile vehicles in which a response record is included. Client ad input is received at 610 and will include not only the image, text, or special offers of the ad, but also a bid specifying a presentation slot and an indication of what the advertiser will pay for a successful presentation. This information, which may be encrypted, is transmitted to the ad server at 620 , which certifies the ad and ranking information at 630 . Part of the certification is a signature of the contents of the certification request, including such items as content of the advertisement and the presentation slot that is requested. This signature protects the advertisement from tampering when it is in transit to a vehicle. The certification also includes ranking information that is computed from the bid to establish a priority among bidders. The certification may be effective for a limited period of time or may be limited by the rate of response to the advertisement. The certified ad is propagated to the vehicle network at 640 under a predetermined policy developed from targeting information supplied by the advertiser, and by geography and traffic loads that the advertisement encounters as it is propagated. Vehicle condition and environmental information may also be used to govern the presentation of the advertisement. At 650 a response is detected from a receiving vehicle. The response may be in the form of a click from the user interface or a drive-to event. The vehicle generates a response record at 660 and sends it to the ad server, which may save the record for billing purposes. The response record provides the coupon identification and associated response event type, and possibly time and location for verification and auditing purposes.
[0029] While the present discussion has been illustrated and described with reference to specific embodiments, further modification and improvements will occur to those skilled in the art. For example, the server may combine or package multiple advertisements or coupons or both while providing certification, or mechanisms may be added during propagation to the network to combine or package multiple coupons in real-time. Additionally, “code” as used herein, or “program” as used herein, is any plurality of binary values or any executable, interpreted or compiled code which can be used by a computer or execution device to perform a task. This code or program can be written in any one of several known computer languages. A “computer,” as used herein, can mean any device which stores, processes, routes, manipulates, or performs like operation on data. It is to be understood, therefore, that this disclosure is not limited to the particular forms illustrated and that it is intended in the appended claims to embrace all alternatives, modifications, and variations which do not depart from the spirit and scope of the embodiments described herein.
[0030] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others. | A method for propagating advertisement for market controlled presentation among communication devices over a communication network accessed by service providers and an advertising service is stored and executed as an application for use by network devices. The method includes receiving advertising requests and bids from potential advertisers, with each bid including a presentation slot specification and a proposed amount of payment for presentation. Ranking information is computed from the bid, with the ranking reflecting the financial value of propagation of the advertising request to the advertising service. The method also provides certification of the advertising request, with certification including a signature of the contents of the advertising request, the requested presentation slot, and the ranking information. The certified advertisement is then propagated over the communication network. | 6 |
FIELD OF THE INVENTION
The present invention relates to a method for manufacturing light-weight foams which are also hard or tough, from crystalline thermoplastic (synthetic) materials. In accordance with the method of the present invention, light-weight foams are prepared by extruding a mixture of crystalline synthetic materials in the presence of a highly volatile organic liquid as the foaming agent.
BACKGROUND OF THE INVENTION
The manufacture of foams by extrusion foaming is known. However, known extrusion processes lead to relatively heavy and soft foam materials. Such foam materials are of limited utility for many applications, and are unsuited for applications where a high resistance to mechanical influences is required.
Light-weight foam materials prepared by extrusion foaming are disclosed by DE-AS 17 94 025. The foams disclosed by this reference are soft and flexible. One disadvantage associated with these foams lies in their inability to resist compression. Moreover, the method of preparation disclosed by the cited reference calls for the use of very large amounts of physical foaming agents. Thus, there are disadvantages associated with the properties of the foams disclosed by DE-AS 17 94 025, as well as with the method of foam preparation disclosed by this reference.
It is an object of this invention to provide a light-weight foam material which is also hard or brittle. Thus, the foams which are the subject of this invention combine the advantages of known light-weight foams such as polyolefin foams, with the desirable hard or brittle properties of other materials such as wood.
BRIEF DESCRIPTION OF THE INVENTION
This invention provides light-weight, but hard foam materials. The foams of this invention are prepared by extruding thermoplastic crystalline plastics in the presence of highly volatile organic liquids as the foaming agents. In accordance with the present method crystalline polyolefins, in the presence of polybutadiene, ethylenevinylacetate copolymers, ethylenepropylenes and/or ethylene-propylene terpolymer rubbers, and optionally;
(a) radical formers such as suitable peroxides, azidene, sulfonyl azidene or the like, and
(b) inhibitors for radical decomposition, such as triallylcyanurate or an acrylate selected from the group consisting of trimethylolpropane-trimethacrylate, allyl-methacrylate, tetrahydrofurfuryl-methacrylate, triethyleneglycol-dimethacrylate, polyethyleneglycol-dimethacrylate or the like, are converted into foam-like molded bodies by means of a highly volatile organic liquid foaming agent. The foaming agent is employed in an amount of from about 5 to about 30% by weight, based on the weight of the polyolefins. The foaming agent and the polyolefins are mixed in an extruder at a temperature of from about 180° to about 280° C., and at a pressure which is greater than the vapor pressure of the foaming agent. The mixture is subsequently extruded.
In accordance with the method of this invention, polyolefin foam materials with specific bulk gravities of from about 30 to about 200 kg/m 3 are obtained. Such light-weight foam materials, which are at the same time hard and brittle, have heretofore been unknown to the art.
DETAILED DESCRIPTION OF THE INVENTION
Suitable crystalline polyolefins for use in accordance with the present method are the isotactic polypropylenes. Preferably, the polypropylenes are foamed in the presence of a polybutadiene, wherein the polybutadiene is present in an amount corresponding to from about 2 to about 20% by weight of the polypropylene and polybutadiene mixture. The mixture is foamed at a temperature of from about 140° to about 180° C.
Suitable polybutadienes include the 1,4-polybutadienes, as well as the liquid 1,2-polybutadienes having molecular weights of from about 500 to about 10,000 g/mol, and having a 1,2-content of at least 35%, and preferably having a 1,2-content of from about 80 to about 95%. Preferred polybutadienes have a molecular weight of from about 1,000 to about 3,000.
When polybutadienes such as those described above are employed, the product polypropylene foam materials may be cross-linked by means of high-energy radiation, such as by electron ray or gamma ray irradiation. The 1,2-content of the polybutadienes has an influence on the cross-linking; that is, the higher the 1,2-content of the polybutadienes, the lower are the radiation doses required for cross-linking the foam for the same amount of polybutadiene. For example, in order to cross-link by electron irradiation a foam with a polybutadiene content of 10% by weight (based on the weight of the polypropylene), wherein the polybutadiene has a molecular weight of 3000 g/mol, and a 1,2-content of 95%, a dose of 5 Mrad is sufficient. An Mrad is defined as 10 (kilojoules of radiation/kilograms of material irradiated). The cross-linked product will have a gel content of about 70%, as determined in boiling xylol. The cross-linking process yields a foam material which is both mechanically and chemically resistant.
In general, radiation doses of from about 0.5 to about 20 Mrads may be successfully employed for cross-linking the foam material. The dose selected depends upon the degree of cross-linking desired and the ultimate properties desired for the final cross-linked product. The higher the degree of cross-linking, the harder and more brittle the foam material becomes.
Preferably, the isotactic polypropylenes are foamed in the presence of from about 0.1 to about 5.0% by weight of radical formers, and from about 0.1 to about 10.0% by weight of radical decomposition inhibitors.
Highly volatile organic liquids are suitable for use as the foaming agents of the present invention. Thus suitable foaming agents include highly volatile hydrocarbons, fluorocarbons, chlorocarbons, fluorochlorocarbons or the like. The foaming agents are employed in amounts corresponding to from about 5 to about 30% and preferably from about 10 to about 15% by weight, based on the weight of the polyolefin components. The foaming agent must be highly soluble in the polymer, and must be retained by the expanding polymer during the foaming process. This is particularly important for the manufacture of light-weight foam materials. If the necessary amount of foaming agent is not held fast and retained by the polyolefin mixture during the foaming process, although light-weight products are obtained for a short time after leaving the extruder, they collapse upon cooling down. This may be the reason that in the process described in DE-AS 17 94 025 relatively large amounts of foaming agent are required. The process disclosed by this reference requires about four- to five-times the amount of foaming agent, than is employed in accordance with the method of this invention. The use of small amounts of foaming agent called for by the present method lowers the overall cost of manufacturing the light-weight foam products of this invention.
It is possible to foam crystalline polyolefins, such as the preferred isotactic polypropylenes, in the presence of polybutadienes by employing volatile solvents as foaming agents. It may be desirable, however, to modify the extrusion foaming process of this invention such that a mixture of high-molecular weight and branched polyolefins are obtained during the process, along with a simultaneous increase in the presence of low-molecular weight polyolefin components. Such mixtures are produced by reactions initiated by adding radical formers to the other reaction components, i.e., the crystalline polyolefin and the polybutadiene. Such radical formers include the peroxides, azides, sulfonyl azides and the like. When polypropylene is employed as the crystalline polyolefin, a further component must be added to the reaction mixture which prevents radical decomposition. Suitable radical decomposition inhibitors include acrylates such as trimethylolpropane-trimethacrylate, allyl-methacrylate, tetrahydrofurfuryl-methacrylate, triethyleneglycol-dimethacrylate, polyethyleneglycol-dimethacrylate and the like, as well as triallylcyanurate, or polybutadiene. The preferred polybutadiene is a 1,2-polybutadiene having at least about a 35% 1,2-content. Inhibitors are recommended for use not only with the preferred isotactic polypropylenes, but also for use with other crystalline polyolefins, such as the polyethylenes.
As a result of the use of the radical formers discussed above, radicals are formed on the polyolefin chains which are made to recombine only in part with other polyolefin chains. In this manner, an increase in the molecular weight of the polyolefins is achieved. The process is carried out only to the extent that a maximum of 5% by weight of gel components which are insoluble in boiling xylol are produced. Moreover, through the use of suitable reaction mixtures part of the polyolefin, and in particular the polypropylene, is decomposed such that a mixture of polyolefins is obtained. This mixture contains a broad distribution of branched and straight-chain polyolefins ranging from low-molecular weight to high-molecular weight polyolefin components. Such mixtures are described in Examples 1 to 6.
Due to the branching, the molecular-weight distributions cannot be precisely determined. For the polypropylenes of Example 5, however, the molecular weight distribution spans a range of from about 1,000 to 4,000,000 gm/mol, with a maximum between about 100,000 and about 200,000. About 4.1% by weight of the modified polypropylene of Example 5 had a molecular weight of from about 1,100,000 and about 9,000,000 gm/mol. Prior to the modification, only 0.05 weight % of the polypropylene had a molecular weight of from about 1,100,000 to about 2,000,000 gm/mol. In the low-molecular region, the weight share of the polypropylene of Example 5 with a molecular weight of from about 600 to about 30,000 gm/mol was 21.8%. The unmodified polypropylene, however, had only 11.9% by weight in the range of from about 3,700 to about 30,000 gm/mol.
When radical former is not employed, it is preferred to employ polyolefins with a broad distribution of molecular weights. Broad molecular weight distributions are readily obtained by mixing polypropylenes of different molecular weights, as disclosed by Examples 7 and 8. It is also possible to employ polypropylenes which are commercially available in the form of a distribution of polypropylenes of various molecular weights. The use of such commercially available polypropylenes is disclosed by Example 9. However, under the same extrusion conditions, a finished foam material having a coarser pore pattern is obtained through the use of such commercially available polypropylenes, as compared to foam materials prepared from polypropylene mixtures prepared by mixing polypropylenes of different molecular weights.
As shown by Example 10, it is necessary in all cases to use a polybutadiene and/or ethylenevinylacetate copolymer or ethylene-propylene or ethylene-propylene terpolymer rubber component. Preferably they are employed in amounts of 2 to 20 weight % relative to the weight of the polypropylene component.
During the foaming process, the high-molecular polyolefins form a framework which prevents the forming foam from collapsing. The low-molecular weight components insure that the physical foaming agents are sufficiently soluble in the polyolefins. This facilitates the extrusion foaming process due to the fact that the extrusion can take place at temperatures lower than those employed by comparable processes. As low-molecular weight components, the 1,2-polybutadienes, in particular, fulfill this task with surprisingly good success.
It is advisable to add the supplemental substances such as 1,2-polybutadiene, between the charging opening of the extruder and about 15 D. The preferred addition is made between 2 D and 5 D, i.e., through an inlet positioned at a length measured from the charging opening of between 2 times and 5 times the diameter of the screw.
In accordance with the method of this invention, lightweight polyolefin foam materials with specific bulk gravities below about 200 kg/m 3 can be obtained through direct gas application, by means of customary machines such as single- or twin-screw extruders, or the so-called tandem systems. Through the modification of the starting materials described above, a considerable reduction in the amount of foaming agents employed is accomplished. Additionally, customary substances such as metal powders, pigments, azodicarbonamide and sodium bicarbonate with citric acid can be used as nucleation agents (pore regulators).
The invention will be described further with reference to the following examples.
EXAMPLE 1
100 parts by weight isotactic polypropylene with a density of 0.90, and a melting index MFI 230° C./2.16 kg; 16 to 20 g/10 min are mixed with 0.5 parts by weight azodicarbonamide, as the pore regulator, as well as with 0.8 parts by weight α,α'-bis (t-butylperoxy)p-isopropyl benzene, a radical former. The mixture is extruded at the rate of 10 kg of material per hour (10 kg/h) by a twin screw extruder (D=34, L (length)=38 D), whereby beyond 5 D a liquid 1,2-polybutadiene with a molecular weight of 3000 g/mol is added at the rate of 0.4 kg/h. The temperature of the melt at the injection point is advantageously between about 180° and about 220° C.
Beyond 15 D, monofluorotrichloromethane is injected at the rate of 0.8 kg/h into the melted polypropylene, which is at a temperature of about 240° C.
During this process, the pressure must be higher than the vapor pressure of the monofluorotrichloromethane at the operating temperature of about 240° C. After the monofluorotrichloromethane has been added to the melt, the latter is cooled down in the extruder to 135° C. After leaving the nozzle, the product foams up and produces a foam material with a specific bulk gravity of 100 kg/m 3 .
EXAMPLES 2-6
In accordance with the procedure of Example 1, foam materials with specific bulk gravities of from 30 to 200 kg/m 3 are obtained employing the polypropylene of Example 1, in the formulations set forth in Examples 2-6 of Table I.
TABLE I__________________________________________________________________________ Specific Bulk GravityExampleRadical Former Nucleation Additive Foaming Agent of the Foam (Kg/m.sup.3)__________________________________________________________________________2 0.4 wt. % α-α' 0.5 wt % 4 wt % Poly- 5 wt % mono- 200Bis(t-butylperoxy) Azodicarbon- butadiene, fluorotrichloro-p-diisopropylben- amide Molecular wt methanezene 30003 0.6 wt % α-α' 0.5 wt % 4 wt % Poly- 8 wt % mono- 100Bis(t-butylperoxy) Azodicarbon- butadiene, fluorotrichloro-p-diisopropylben- amide Molecular wt methanezene 30004 0.8 wt % α-α' 0.5 wt % 6 wt % Poly- 10 wt % mono- 50Bis(t-butylperoxy) Azodicarbon- butadiene, fluorotricarbon-p-diisopropylben- amide Molecular wt methanezene 30005 0.8 wt % α-α' 0.5 wt % 5 wt % Poly- 15 wt % mono- 30Bis (t-butylperoxy) Azodicarbon- butadiene, fluorotrichloro-p-diisopropylben- amide Molecular wt methane and tri-zene 3000 fluorotrichloro- ethane (1:1)6 0.8 wt % α-α' 0.5 wt % 7 wt % Poly- 15 wt % mono- 30Bis(t-butylperoxy) Azodicarbon- butadiene, fluorotrichloro-p-diisopropylben- amide Molecular wt methane and tri-zene 3000 fluorotrichloro- ethane (1:1)__________________________________________________________________________
The foams produced by this method having a specific bulk gravity of 50 kg/m 3 can withstand a compression load of 47 N/cm 2 . Such foams are deformed by only about 2 mm, and break down above 47 N/cm 2 . N refers to one Newton or 10 5 dynes.
Gal-chromatography examination of the polypropylene of Example 5 showed the presence of 4.1 weight % polypropylene with a molecular weight in the range of 1,100,000 to 9,000,000 gm/mol. The starting polypropylene reactant contained less than 0.05 weight % polypropylene with a molecular weight above about 1,100,000 gm/mol. The weight average of the molecular weight of the starting polypropylene was 200,000 gm/mol. The weight average of the molecular weight of the modified polypropylene was 236,000 gm/mol.
EXAMPLE 7
30 parts by weight of a polypropylene with an average molecular weight of 200,000 gm/mol are mixed with 40 parts by weight of a polypropylene with an average molecular weight of 400,000 gm/mol, as well as with 20 parts by weight of a polypropylene with an average molecular weight of 640,000 gm/mol, and 10 parts by weight of a propylene with an average molecular weight of 800,000 gm/mol; 0.2 parts by weight azodicarbonamide is added to this mixture.
The mixture is extruded at the rate of 10 kg/h via a twin-screw extruded (D=34, L=28 D), where beyond 5 D, liquid 1,2-polybutadiene with a molecular weight of 3000 g/mol is added at the rate of 1 kg/h.
Beyond 15 D, monofluorotrichloromethane and trifluorotrichloroethane (mixed 1:1) are injected at the rate of 1.4 kg/h into the melted polypropylene at a temperature of about 250° C. During this process, the pressure in the melt must be higher than the vapor pressure of the monofluorotrichloromethane, at a temperature of about 250° C. After the monofluorotrichloromethane/trifluorotrichloroethane mixture has been added to the melt, the latter is cooled in the extruder down to about 155° C.
After leaving the nozzle, the product foams up and yields a foam material with a specific bulk gravity of 40 kg/m 3 .
The foam material produced in this manner can be crosslinked with electron rays at a dose of 6 Mrad to the extent that the gel content in boiling xylol is 80%.
EXAMPLE 8
30 parts by weight of a polypropylene with an average molecular weight of 200,000 gm/mol are mixed with 40 parts by weight of a polypropylene with an average molecular weight of 400,000 gm/mol, as well as with 30 parts by weight of a polypropylene with an average molecular weight of 800,000 gm/mol. 0.2 parts by weight of azodicarbonamide is added to this mixture.
The mixture is extruded at the rate of 10 kg/h via a twin-screw extruder (D=34, L=28 D). Beyond 5 D, liquid 1,2-polybutadiene with a molecular weight of 3000 g/mol is added at the rate of 1 kg/h. Beyond 15 D, monofluorotrichloromethane and trifluorotrichloroethane (mixed 1:1) are injected into the melted polypropylene at a rate of 1.4 kg/h, which is at a temperature of about 250° C. The pressure of the melt must be higher than the vapor pressure of the monofluorotrichloromethane at a temperature of about 250° C. After the monofluorotrichloromethane/trifluorotrichloroethane mixture has been added, the melt is cooled in the extruder down to 155° C. After leaving the nozzle, the product foams up, and yields a foam material with a specific bulk gravity of 40 kg/m 3 .
EXAMPLE 9
100 parts by weight of a polypropylene with an average molecular weight of 400,000 gm/mol is reacted with 0.2 parts by weight azodicarbonamide.
The mixture is extruded at the rate of 10 kg/h, via a twin-screw extruder (D=34, L=28 D). Beyond 5 D, liquid 1,2-polybutadiene with a molecular weight of 3000 g/mol is added at the rate of 1 kg/h. Beyond 15 D, 1.4 kg/h of monofluorotrichloromethane and trifluorotrichloroethane (mixed 1:1) are injected into the melted polypropylene which is at about 250° C. The pressure in the melt must be higher than the vapor pressure of the monofluorotrichloromethane at a temperature of about 250° C. After the monofluorotrichloromethane/trifluorotrichloroethane mixture has been added, the melt is cooled down to 155° C. in the extruder. After leaving the nozzle, the product foams up and yields a foam material with a specific bulk gravity of 40 kg/m 3 .
EXAMPLE 10
The polypropylene mixture of Example 8 was extruded under the same conditions as described in Example 8, but without the addition of polybutadiene. The foam material obtained had a specific bulk weight of only about 650 kg/m 3 .
EXAMPLES 11-13
Following the procedure of Example 9, foam materials having specific bulk weights of 80 and 100 kg/m 3 are obtained by employing the formulations of Examples 11-13.
TABLE II__________________________________________________________________________Weight % and Average Specific BulkMolecular Weight Foaming Gravity of theExampleof the Polypropylene Nucleation Additive Agent Foam (Kg/m.sup.3)__________________________________________________________________________11 30 wt % 200 kg/mol 0.2 wt % 2 parts by 15 wt % 10040 wt % 400 kg/mol Azodicarbon- weight, poly- monofluoro-30 wt % 800 kg/mol amide butadiene, trichloro- molecular wt methane and 3000 g/mol trifluoro- trichloro- ethane (1:1)12 as per Example 11 0.2 wt % 5 parts by 15 wt % 80 Azodicarbon- weight, poly- monofluoro- amide butadiene, trichloro- molecular wt methane and 3000 g/mol trifluoro- trichloro- ethane (1:1)13 as per Example 11 0.2 wt % 20 parts by 15 wt % 100 Azodicarbon- weight, monofluoro- amide ethylene- trichloro- propylene- methane and copolymer (EPM) trifluoro- trichloro- ethane (1:1)__________________________________________________________________________
EXAMPLE 14
100 parts by weight polyethylene (density 0.96; melting index MFI 190° C./5 kg; 4 g/10 min) are mixed with 0.5 parts by weight azodicarbonamide, a pore regulator, as well as with 0.1 parts by weight dicumylperoxide, a radical former. The mixture is extruded at the rate of 10 kg/h in a twin-screw extruder (D=34, L=28 D), where beyond 5 D a liquid polybutadiene with a molecular weight of 3000 g/mol is added at the rate of 0.4 kg/h.
Beyond 15 D, monofluorotrichloromethane is injected into the melted polyethylene which is at a temperature of approximately 200° C. at the rate of 1.4 kg/h. The pressure in the melt must be higher than the vapor pressure of the monofluorotrichloromethane at a temperature of 200° C. After the monofluorotrichloromethane has been added to the melt, the latter is cooled in the extruder down to 90° C. After leaving the nozzle, the product foams up and yields a foam material with a specific bulk gravity of 50 kg/m 3 .
EXAMPLES 15-18
Table III sets forth the specific bulk gravities of foams obtained by employing the polyethylene of Example 14 and the formulations of Examples 15-18. The preparative procedure followed is that of Example 14.
TABLE III__________________________________________________________________________ Specific Bulk GravityExampleRadical Former Nucleation Additive Foaming Agent of the Foam (Kg/m.sup.3)__________________________________________________________________________15 0.2 wt % 0.2 wt % -- 10 wt % mono- 80dicumylperoxide azodicarbon- fluorotrichloro- amide methane16 0.1 wt % 0.2 wt % 0.2 wt % 18 wt % mono- 30dicumylperoxide azodicarbon- polybutadiene fluorotrichloro- amide molecular methane weight 300017 0.05 wt % 0.2 wt % 0.6 wt % 14 wt % mono- 50dicumylperoxide azodicarbon- polybutadiene fluorotrichloro- amide molecular methane weight 300018 0.2 wt % 0.2 wt % 0.1 wt % 8 wt % mono- 100dicumylperoxide azodicarbon- polybutadiene fluorotrichloro- amide molecular methane weight 3000__________________________________________________________________________
This invention has been described in terms of specific embodiments set forth in detail herein. It should be understood, however, that these are by way of illustration only and that the invention is not necessarily limited thereto. Modifications and variations will be apparent from this disclosure and may be resorted to without departing from the spirit of this invention, as those skilled in the art will readily understand. Accordingly, such variations and modifications of the disclosed embodiments are considered to be within the scope of this invention and the following claims. | This application is directed to light-weight and hard foam materials. The foams of this invention are prepared by extruding thermoplastic crystalline plastics in the presence of highly volatile organic liquids as the foaming agents. In accordance with the present method crystalline polyolefins, in the presence of polybutadiene, ethylenevinylacetate copolymers, ethylene-propylenes and/or ethylene-propylene terpolymer rubbers, and optionally radical formers such as suitable peroxides, azidene, sulfonyl azidene or the like, and inhibitors for radical decomposition, such as triallylcyanurate or an acrylate selected from the group consisting of trimethylolpropane-trimethacrylate, allyl-methacrylate, tetrahydrofurfurylmethacrylate, triethyleneglycol-dimethacrylate, polyethyleneglycol-dimethacrylate or the like, are converted into foam-like molded bodies by means of a highly volatile organic liquid foaming agent. The foaming agent is employed in an amount of from about 5 to about 30% by weight, based on the weight of the polyolefins. The foaming agent and the polyolefins are mixed in an extruder at a temperature of from about 180° to about 280° C., and at a pressure which is greater than the vapor pressure of the foaming agent. The mixture is subsequently extruded. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for manufacturing a composite high voltage insulator in which a plurality of skirts are manufactured and joined to a rod, and more particularly to a method for manufacturing a composite high voltage insulator in which an expanding pipe is inserted into a plurality of skirts arranged in a line by a skirt holder to expand the inner diameters of the skirts, so that the skirts reach precise positions of the rod, and an adhesive agent is easily applied, so that an interface between different materials is not formed in order to improve reliability of insulator products.
2. Description of the Related Art
Generally, insulators are used to simultaneously insulate and mechanically maintain or support power transmission lines or naked wires of electric equipment, and include a plurality of bellows to achieve sufficient dielectric strength in order to increase the distance thereof per surface area. These bellows prevent the deterioration of the dielectric strength of the insulator, when the surface of the insulator is wet, particularly when salt content or dust is attached to the surface of the insulator.
The above insulators are divided according to application into suspension insulators used in power transmission lines, long-rod insulators, fog-type insulators used to withstand typhoon-force winds, pin insulators used in distribution lines, knob insulators used in interior wirings, insulating tubes, cleat insulators, and support insulators used in circuit breakers or arresters.
FIG. 1 is a sectional view of a conventional composite insulator.
The conventional composite insulator 20 comprises a sheath portion 22 formed on the outer surface of a core rod 10 made of FRP by covering the core rod 10 with a material having a high resistance to environments, such as air pollution or ultraviolet rays, for providing mechanical stress, and skirt portions 24 including sheds formed integrally with the sheath portion 22 .
FIG. 2 is an exploded sectional view of the conventional composite insulator illustrating a modular-type method for manufacturing the conventional composite insulator.
The length of composite insulators used in superhigh-voltage lines increases in direction proportion to increase in service voltage. The increased length of the composite insulator generates various problems in a process for manufacturing the composite insulator.
A method for manufacturing the composite high voltage insulator by injection molding once does not form an interface between different materials, thus producing the most reliable product. However, since the composite high voltage insulator has a length of 3˜7 m, it is difficult to solve the warpage of the rod 30 , and since a mold corresponding to the length of the composite insulator and a large-volume catapult are essentially required, initial costs are increased.
In order to solve the above problems, a modular method, in which a sheath 34 and skirts 40 are separately molded and are then assembled and attached, has been proposed. In the above modular method for manufacturing a composite high voltage insulator, the sheath 34 and the skirts 40 are separately molded, the sheath 34 is inserted into holes formed through the skirts 40 , and an adhesive agent is applied to an interface between the sheath 34 and the skirts 40 to attach the sheath 34 and the skirts 40 .
The above conventional method for manufacturing a composite high voltage insulator is divided into two approaches. The first approach is where an adhesive agent is applied to the outer surface of the rod 30 covered with the sheath 34 and the rod 30 is inserted into the holes of the skirts 40 such that the skirts 40 slide towards the inside of the rod 30 using the lubricating function of the adhesive agent In this approach, when the inner diameters of the skirts 40 are excessively small, the adhesive agent applied to the rod 30 covered with the sheath 34 is peeled off by inserting the rod 30 into the holes of the skirts 20 . Accordingly, it is difficult to uniformly apply the adhesive agent to the overall surface of the rod 30 .
Further, when the inner diameters of the skirts 40 are excessively large, it is easy to insert the rod 30 into the holes of the skirts 40 . However, in this case, adhesive characteristics caused due to the compressive force of the skirts 40 are not obtained, and an air layer may be formed in the interface between the skirts 40 and the sheath 34 after the manufacture of the insulator is completed. The above approach is disadvantageous in that the exposed adhesive agent generates an interface between difference materials, the above interface is a weak point of the composite insulator requiring the reliability, and the adhesive agent must have improved resistance to tracking and weather so that the composite insulator is proper to be used outdoors.
The second approach is that an adhesive agent is applied only to the inner walls of the holes of the skirts 40 or is applied to the surface of the rod 30 covered with the sheath 34 to be inserted into the holes of the skirts 40 so that the skirts 40 are attached to the rod 30 using the adhesive agent by inserting the rod 30 into the holes of the skirts 40 under the condition that the holes of the skirts 40 are expanded and then by releasing the expanded state of the holes of the skirts 40 . However, this approach is disadvantageous in that it is difficult to expand the holes of the skirts 40 due to the general shapes of the skirts 40 and characteristics of materials of the skirts 40 .
SUMMARY OF THE INVENTION
Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a method for manufacturing a composite high voltage insulator in which a plurality of skirts are arranged in a line in a skirt holder and an expanding pipe is then inserted into the skirts under the condition that the expanding pipe is rotated to easily expand the inner diameters of the skirts so that an adhesive agent is uniformly applied to the outer surface of a rod by preventing the agent from being peeled off when the rod is inserted into the skirts, and the adhesive agent is not applied to the portion of the rod exposed to the outside to prevent the formation of an interface between different materials.
In accordance with the present invention, the above and other objects can be accomplished by the provision of a method for manufacturing a composite high voltage insulator comprising: manufacturing a plurality of skirts, and manufacturing a rod by covering an outer surface of an FRP rod with a sheath so that the skirts are continuously disposed along the cylindrical surface of the rod; arranging the skirts in a skirt holder such that the skirts are connected in a line; expanding inner diameters of the skirts by applying an adhesive agent to the outer surface of an expanding pipe and inserting the expanding pipe into the holes of the skirts under the condition that the expanding pipe is rotated at a designated speed; inserting the rod into the expanding pipe; positioning the inner surfaces of the holes of the skirts to contact the outer surface of the rod by separating the expanding pipe from the holes of the skirts; and hardening the adhesive agent by heating the skirts and the rod to a designated temperature for a designated time.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a sectional view of a conventional composite insulator,
FIG. 2 is an exploded sectional view of the conventional composite insulator,
FIG. 3 is a sectional view illustrating the expansion of inner diameters of skirts in a method for manufacturing a composite high voltage insulator in accordance with the present invention;
FIG. 4 is a sectional view illustrating the insertion of a rod into an expanding pipe in the method of the present invention;
FIG. 5 is a sectional view illustrating the state of a skirt holder after the insertion of the rod into the expanding pipe in the method of the present invention is completed;
FIG. 6 is a sectional view illustrating the separation of the expanding pipe from the skirts in the method of the present invention; and
FIG. 7 is a sectional view illustrating the composite insulator manufactured by the method of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, a preferred embodiment of the present invention will be described in detail with reference to the annexed drawings.
FIG. 3 is a sectional view illustrating the expansion of inner diameters of skirts in a method for manufacturing a composite high voltage insulator in accordance with the present invention. FIG. 4 is a sectional view illustrating the insertion of a rod into an expanding pipe in the method of the present invention. FIGS. 5 and 6 are sectional views illustrating the state of a skirt holder after the insertion of the rod into the expanding pipe in the method of the present invention is completed.
The method for manufacturing a composite high voltage insulator in accordance with the present invention comprises manufacturing a plurality of skirts 40 , and manufacturing a rod 30 by covering the outer surface of an FRP rod 32 with a sheath 34 so that the skirts 40 are continuously disposed along the cylindrical surface of the rod 30 , arranging the skirts 40 in a skirt holder 50 such that the skirts 40 are connected in a line, expanding the inner diameters of the skirts 40 by applying an adhesive agent to the outer surface of an expanding pipe 60 and inserting the expanding pipe 60 into holes of the skirts 40 under the condition that the expanding pipe 60 is rotated at a designated speed, inserting the rod 30 into the expanding pipe 60 , Positioning inner surfaces of the holes of the skirts 40 to contact the outer surface of the rod 30 by separating the expanding pipe 60 from the holes of the skirts 40 , and hardening the adhesive agent by heating the skirts 40 and the rod 30 to a designated temperature for a designated time.
In the manufacture of the skirts 40 and the rod 30 , the manufacture of the skirts 40 is achieved by general molding, and as shown in FIG. 2 , a plurality of the skirts 40 are manufactured such that the skirts 40 are separated from each other.
The manufacture of the rod 30 is achieved by extrusion molding in which the outer surface of the FRP rod 32 is covered with the sheath 34 . Here, the sheath 34 is formed on the RFP rod 32 separated from the skirts 40 by the extrusion molding, thereby allowing the rod 30 having a length of approximately 3 m to have a designated shape without partial disposition.
In the arrangement of the skirts 40 , a plurality of the skirts 40 are continuously arranged in the skirt holder 50 such that the skirts 40 are spaced from each other by a designated interval. Here, the skirt holder 50 restrains the skirts 40 , thereby allowing the expanding pipe 60 to be inserted into the holes of the plural skirts 40 by a single process. The skirt holder 50 may have various structures so long as the skirt holder 50 can support the plural skirts 40 without movement.
In the expansion of the inner diameters of the skirts 40 , the expanding pipe 60 , which is installed on a transfer system 70 such that the expanding pipe 60 is rotated at a designated speed and rectilinearly moves in a horizontal direction, is moved by the transfer system 70 and enters into the skirt holder 50 , thereby being instead into the holes of the skirts 40 .
Here, the inner diameter of the expanding pipe 60 is larger than the outer diameter of the rod 30 by approximately 1˜5 mm so that the rod 30 can be inserted into the expanding pipe 60 . Preferably, the expanding pipe 60 is made of an aluminum pipe having a thickness of approximately 1.5˜5 mm.
A designated pattern is formed on the outer surface of the expanding pipe 60 so that the roughness of the outer surface of the expanding pipe 60 is increased, thereby allowing the adhesive agent to be maximally uniformly applied to the outer surface of the expanding pipe 60 . Further, a front end 62 of the expanding pipe 60 has a conical shape so that the expanding pipe 60 can be more easily inserted into the holes of the skirts 40 .
Hereinafter, the method for manufacturing the above composite insulator of the present invention will be described.
First, the skirts 40 , which were manufactured in advance by molding, are installed in the skirt holder 50 , and the adhesive agent is applied to the outer surface of the expanding pipe 60 . Then, the expanding pipe 60 is inserted into the holes of the skirts 40 under the condition that the expanding pipe 60 is rotated, thereby expanding the inner diameters of the skirts 40 .
The rotational speed of the expanding pipe 60 is varied according to the number of the skirts 40 , into which the expanding pipe 60 is inserted. Most preferably, the rotational speed of the expanding pipe 60 is 30˜300 rpm. The expansion of the inner diameters of the continuously arranged skirts 40 is more easily achieved by the lubricating function of the adhesive agent applied to the outer surface of the expanding pipe 60 .
The skirts 40 are mounted on the outer surface of the rod 30 by inserting the rod 30 into the expanding pipe 60 and then separating the expanding pipe 60 from the skirts 40 as described above.
Thereafter, the skirt holder 50 provided with the skirts 40 and the rod 30 is hardened in a space maintained at a high temperature of 100˜200° C. for at least 1 minute. Thereby, a composite high voltage insulator having a structure in which the adhesive agent is not exposed to the outside is manufactured.
[An Embodiment]
In accordance with an embodiment of the present invention, rods are manufactured by respectively covering FRP rods having diameters of 22 mm and 26 mm with sheathes made of silicon rubber having a thickness of 5 mm by extrusion molding. Then, the sheathes of the rods have thicknesses of 32 mm and 36 mm by vulcanization at a temperature of 270° C. for 10 minutes.
Skirts are manufactured such that the inner diameters of the skirts are smaller than the outer diameters of the rods by 1˜5 mm, and expanding pipes are manufactured such that the inner diameters of the expanding pipes are larger than the outer diameters of the rods by 1˜5 mm.
As apparent from the above description, the present invention provides a method for manufacturing a composite high voltage insulator, in which an expanding pipe to which an adhesive agent has been applied is simultaneously rotated and inserted into a plurality of skirts so that a rod is inserted into the expanding pipe under the condition that holes of the skirts are expanded, and the expanding pipe is then separated from the skirts, thereby mounting the skirts on precise positions of the outer surface of the rod so that the adhesive agent is uniformly applied between the skirts and a sheath and preventing the adhesive agent from being exposed to the outside of the insulator so that reliability of the composite high voltage insulator product is improved. Further, the method of the present invention is easily performed, thus reducing the time and costs taken to manufacture the composite high voltage insulator.
Although the preferred embodiment of the present invention has 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. | Disclosed is a method for manufacturing a composite high voltage insulator in which a plurality of skirts are manufactured and joined to a rod, and more particularly to a method for manufacturing a composite high voltage insulator in which an expanding pipe is inserted into a plurality of skirts arranged in a line by a skirt holder to expand the inner diameters of the skirts, so that the skirts are mounted on precise positions of the rod, and an adhesive agent is easily applied, so that an interface between different materials is not formed in order to improve reliability of insulator products. | 8 |
FIELD OF THE INVENTION
The present invention relates to emergency valve apparatus articularly for use in fluid systems in process industries.
There is a serious danger in process industries of a fire causing the failure of flow controllers and/or of lines containing toxic, flammable and otherwise hazardous gases or liquids. In principle, a method to minimize this danger is the installation in process industry fluid carrying lines of a small, inexpensive, instantaneously acting, fire temperature sensitive shut off valve which is self actuating (no batteries or other power sources). Such valves could be installed in-line at frequent intervals and/or in place of fittings. It could also be installed at the entrances and exits of fluid control assemblies in order to provide isolation of the assemblies in the event of a fire.
The term "process industry fluid line", or the like, as used herein means dangerous liquid or dangerous gas carrying networks carrying such fluid at high pressure (at least 500 psi; and typically 300-3000 psi) in piping of less than six inches diameter typically 1/8-1 inch with an aggregate network length of such piping of over one hundred running feet.
BACKGROUND OF THE INVENTION
Currently, in order to provide fire safety in process industry, an arrangement of multiple elements is provided, with each such assemb1y comprising a heat detector (usually a thermocouple), a relay, an actuator (usually electrical, hydraulic, or pneumatic) and a power source The heat detector, when it detects fire temperature, sends an electrical signal to a relay, which uses this low level signal to control the power from a power source, either electrical, pneumatic, or hydraulic. The applied power drives the actuator to close the valve. Actuating power itself and relay supporting power is derived from a network overlapping the process industry fluid network and such power sources are vulnerable to fire. It has been proposed in U.S. Pat. No. 3,664,582, issued May 23, 1972, to W. F. Jackson et al. and in U.K. Pat. No. 1308107 of Vereinigte Flugtechnishche WerkeFokker GmbH, published Feb. 28, 1973, to use as the temperature detector an element made of a nickel titanium alloy and having a temperature actuated shape memory. This provides local relay function and power independent of external power. This arrangement is slower to act than is necessary, is too expensive for widespread use, occupies a large volume of space, and because of the large number of component parts is less reliable than needed. Also of interest are the sprinkler control valve systems described in copending U.S. application Ser. No. 890,026, filed Sept. 28, 1986 by Schetky et al., now abandoned, for fire sprinkler valve-opening mechanism and the like using shape memory actuation.
It is an object of the present invention to provide an emergency valve module which meets a need for reliable, fast response valves with self contained power source, in a way that is economical for effecting shut down of process fluid flow.
It is a further object of the invention to provide simple test capability integral to the valve consistent with the foregoing object.
SUMMARY OF THE INVENTION
In accordance with the present invention a shut off valve having an actuator which is also the temperature sensor is provided. External power sources and intermediary control devices are not needed. A combined actuator/sensor is made of a shape memory alloy. The properties of shape memory materials and designs for utilizing them are descrited in the above cited application of Schetky et al. and elsewhere.
The shape memory effect alloy material is tailored for use herein to have a transition temperature range (which is dependent on the composition and production custom of the material) such that the valve closes at required temperatures. While it is possible to employ many shape memory effect materials for the valve member, including the nickel-titanium alloy referred to in the above mentioned patents, it is preferred to use copper based alloys as described in Schetky et al.
Other objects, features, and advantages will be apparent from the following detailed description of preferred embodiments taken in conjunction with the accompanying drawing in which:
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an axial section through a first embodiment shut off valve in accordance with the invention;
FIGS. 2 and 3 are similar sections of other such embodiments incorporating a test capability; and
FIG. 4 is a similar section of further such embodiment operating as a pilot valve in cooperation with a main valve to be shut down in an emergency.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1 a passage is shown at 5 for the passage of fluid (liquid or gas) to be controlled in the case of fire. The passage 5 is connected to tubing or piping of a process by means of welding, threaded connections, compression fittings, or other means at 6. A valve member 7, called a lower stem, seals against an orifice, the edges of which comprise a seat 8. The lower stem 7 is welded to a diaphragm 9. The diaphragm is held in position, thus effecting a seal, by the threaded valve member 10 called a bonnet. The diaphragm 9 isolates the process fluid, which passes through piping sections 5 and 6, from the valve mechanisms. A diaphragm is just one example of means to contain the process fluid within the valve. Other means are also commonly used.
The diaphragm 9 is also connected to the upper stem 3 which is driven by the shape memory effect actuator 1 and bias spring 2 sub-assembly. Bias spring 2 biases spring 1 away from the fully closed condition as shown in FIG. 1. Stem 3 has a threaded portion 11 upon which a threaded disc 12 is positioned to contain the bias spring 2 and to adjust the amount of bias spring load. A threaded plug 13 allows for adjustment of the shape memory effect actuator length and thus operating performance. The compression spring 1 is made of shape memory effect alloy having an elastic modulus which varies significantly with temperature in a reversible manner over a transition temperature range. Such an alloy is well known, the alloy preferred for use in the present invention being a copper based alloy.
The actual proportions of the constituents vary according to the temperature requirements. The alloy consists of between 68 and 80 percent copper. The remaining twenty to thirty two percent consists of zinc and aluminum in various proportions. Lower aluminum containing alloys have lower transformation temperatures than high aluminum content alloys.
The alloy is heat-treated to bring it into a condition in which it exhibits a martensitic transformation when subject to temperature change in the transition range. The alloy is heated until its crystal structure assumes a high temperature configuration called the beta phase. Next the alloy is rapidly cooled so that the atoms in the metal rearrange themselves into the crystal form of martensite. The characteristic displayed by the alloy is progressive increase in stiffness of the spring 1 as the temperature rises through the range. At or below the lower end of that range, the stiffness is low and bias spring 2 which does not show a significant change in elastic modulus with temperature, urges spring 1 into the condition shown. As the temperature of spring 1 increases, the stiffness also increases with the result that the turns of the spring are progressively spaced apart generating force as they expand.
The FIG. 2 embodiment comprises a variation of the actuating mechanism of FIG. 1. In this variation items 3-12 are functionally identical to items 3-12 of FIG. 1. A valve closure spring 14 of conventional spring material is positioned around stem 3. The amount of spring load is adjustable by either disc 12 or plug 13. The spring load cannot drive the stem 3 to close the valve because of the presence of the detent ball 15 in the circumferential groove 16 in the stem 3. The detent ball is held in position against the force of the valve closure spring 14 by the bias spring 17 which is contained in housing 18 which is attached into 10. Bias spring 17 is positioned around shaft 20. Housing 19 is threaded into housing 18, the degree of insertion providing adjustment of the bias spring force. The helical coil shape memory spring 21 is positioned around shaft 20 between the wall of housing 19 and the positionally adjustable disc 22. Shaft 20 is threaded in the vicinity of disc 22 to allow adjustment of the shape memory spring length and thus performance. A handle for testing 23 is provided at the end of the shait 20 and a reset handle is provided at the end of stem 3.
FIG. 3 shows a variation of the FIG. 2 structure. A rectangular bending beam shape memory actuator is utilized as an example of other configurations of shape memory elements that could be used to generate force and displacement. Items 1-20 are functionally identical to items 1-20 of FIG. 2. Shape memory element 21 is held in position against housing collar 25 which is fixed to shaft 20 by threaded means.
For low process pressures valve sealing forces are relatively low and the actuator may act directly to seal the valve such as illustrated in FIG. 1. This valve is similar to conventional diaphragm seal valves (a bellows seal could also be used). A metal to metal orifice seal is provided in case fire reaches the valve. The diaphragm isolates the actuating mechanisms from the process fluid. When ambient temperature rises above the transition temperature the shape memory actuator (1) undergoes a phase transformation and expands overcoming the opposing force of the bias spring 2. The shape memory actuator drives the stem 3 into the seat 4 effecting a seal. When the ambient air cools below the transition temperature the shape memory actuator, having two way memory contracts back to the closed position, opening the valve. If desired, a detent mechanism could be used to prevent the valve from opening when the ambient air cools.
For higher process pressures larger forces are needed to seal the valve. Shape memory effect actuators having larger mass would te needed to generate these larger closure forces. Actuators with larger mass will respond slower to a heat impulse than smaller mass actuators. To insure fast reaction to a heat impulse indirect operation is desirable wherein a relatively small shape memory effect force controls the necessary larger valve closure force. Such a valve is illustrated in FIG. 2. This valve has the features of testability and resettability. Stem 3 thereof is biassed to closure by means of the relatively strong compressed steel valve closure spring 14. It is prevented from closing by the detent ball. The detent ball is held in position by the actuator shaft 20 and the relatively weaker bias spring 17 which is in compression. At room temperature the shape memory spring 21 is fully closed. At fire temperature it expands to the right, instantly overcoming the force of the bias spring 17. The force on ball detent 15 is released allowing the valve closure spring 14 to push the stem down, closing the valve. The valve can be tested by pulling the test handle 23, overcoming the bias spring 17. The valve will now close. Releasing the test handle and pulling the reset handle 24 will compress the valve closure spring 14. When the tall detent 15 snaps into place the reset handle can be released. This valve could also function as an on-off valve. Pulling the test handle 23 closes the valve. Pulling the reset handle 24 opens the valve.
FIG. 2 shows the shape memory actuator in the form of a helical coil spring. Other forms of actuator such as cantilever, bending team, or others may be used.
FIG. 3 shows an alternate method of actuation using a shape memory bending beam 21A (solid lines) shown in the tending beam position at temperature below the transition temperature. When the ambient air temperature rises above the transition temperature the beam bends (dotted lines) releasing the holding force on the detent ball 15, allowing the valve closure spring 14 to close the valve, as described above.
FIG. 4 shows an embodiment of the invention usable in a pneumatic control system.
In a pneumatic control system air pressure opens and closes a process line valve allowing or stopping the flow of process fluid. In the event of a fire or other over temperature emergency it may be desirable to quickly open or close the process line valve. Detection systems such as described above may be used to change the air pressure to an emergency condition (on or off). Such systems have the limitations described above. A more reliable, faster acting means is shown in FIG. 4 installed into a commonly available commercial air operated process line valve 26. A shape memory effect spring 51 is positioned to drive a flange 36, shaft 55 and poppet 40 against the force of a bias spring 42. The shape memory actuated valve controls the air supply to the air operated valve 26 which controls the process fluid. The air operated valve, comprising a piston 28 is controlled by air from a pressure source 30P and valve 30V admitting air via passage 30-1, 30-2, 30-3 to force the piston upward against a bias spring (or allow the piston to close as air feed, or pressure use, is attenuated or reversed). The shape memory actuated valve reacts to an emergency over temperature condition by releasing the control air pressure to atmosphere, depriving the air operated valve of its air via path 30-1, 30-4 supply. Control air pressures are typically 30-100 psi, the return spring 32 is made of conventional metal and is constructed so that, when air pressure is relieved, it drives the valve mechanisms opposite to the force of the air opening or closing the process line valve, as desired. Thus closure or opening of the process line is achieved by deprivino the air operated valve of its air supply. Alternatively to releasing the control air to atmosphere is closing the control air ports, means of blockage of the air.
It will now be apparent to those skilled in the art that other embodiments, improvements, details, and uses can be made consistent with the letter and spirit of the foregoing disclosure and within the scope of this patent, which is limited only by the following claims, construed in accordance with the patent law, including the doctrine of equivalents. | Self actuating valve systems for fluid line networks comprising a main valving stem (3) with a driving-to-close bias spring (14) which is blocked by a detent ball (15) from closure against a valve seal (8), the ball itself being held by a removable pilot stem biassed to such holding action by a spring (17), the force of which can be automatically overcome at emergency temperature use condition by high force action of a shape memory spring (21). The main valving stem is manually resettable and the shape memory drivable pilot stem and related drive system are manually testable. A plurality of such valve systems are distributed in a fluid flow network for isolating an emergency temperature rise (e.g., fire region). | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is in the field of continuous dyeing of textile webs comprising cellulosic fibers with vat dyes.
2. Description of the Prior Art
The continuous vat dyeing of cellulosic fibers such as cotton and rayon alone or in combination with other fibers is an important industrial process.
Representative of trade processes for the continuous vat dyeing of textile webs is the process of Stott et al as described in U.S. Pat. No. 2,487,197. The process of Stott et al, in brief, comprises first the step of padding a clean textile web with an aqueous dispersion comprising a vat dye in the oxidized form, a process called pigment padding in the trade. Thereafter, usually following drying, the web is padded with a pad liquor comprising a reductant. The most commonly used reductant is sodium hydrosulfite combined with an approximately equal amount of sodium hydroxide. Following this process step, called chemical padding in the trade, the web is passed through an essentially anaerobic steamer where the dye is reduced to the sodium hydroxide-soluble leuco form which becomes fixed on the web. After leaving the steamer the dye is reoxidized to the insoluble form, normally by contacting the web with an aqueous oxidizing agent such as chromic acid-acetic acid or sodium perborate. Soaping, rinsing and drying of the web completes the process.
Although it is not the usual practice, it is also possible, in a similar process, to pad vat dyes onto the web in the leuco form. In this process one employs an aqueous pad liquor comprising the vat dye in mixture with a reductant.
In dyeing webs comprising blends of cellulosic fibers with other fibers, it is usual to add other dyes suitable for the noncellulosic fiber. For example, a disperse dye may be added to dye polyester fibers in cotton-polyester blend. Between the steps of pigment padding and chemical padding the disperse dyes are normally fixed by heating.
The above described dyeing processes produce substantial amounts of waste water effluent. The dyeing and finishing segment of the textile industry, in which the instant invention would be employed, is under increasing pressure to reduce its effluent to the environment.
SUMMARY OF THE INVENTION
In the process of continuous vat dyeing of a textile web comprising passing said web through a steamer having a web entrance and a web exit, and applying reductant-comprising liquor to said web by means situate at or near said web entrance, the improvement, characterized by savings of reductant and reduced effluent, consisting in:
A. applying reductant-comprising liquor to said web by means situate at or near said web entrance in excess of that expressable by squeeze rolls;
B. expressing liquor from said web by means of squeeze rolls at or near said web exit; and
C. collecting and applying expressed liquor to said web together with reductant-comprising liquor by said means situate at or near said web entrance.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows an embodiment of the invention wherein a padder functions to apply liquor to the web.
FIG. 2 is a graph relating savings of reductant expressed as percent of the excess applied to the web versus the weight ratio of liquor applied to the web at or near the web entrance to the liquor remaining on the web after passing between squeeze rolls at or near the web exit.
DETAILED DESCRIPTION OF THE INVENTION
I prefer to carry out the invention process in a device essentially as shown in FIG. 1. FIG. 1 is a longitudinal section through a steamer wherein in this embodiment dry, pigment padded textile web 1 enters steam filled enclosure 2 after passage through a chemical padder serving also as a seal and comprising padder pan 3 containing reductant-comprising liquor 4, guide roll 5 and rubber covered squeeze rolls 6. Feed assembly 7, responsive to the liquid level of chemical pad liquor 4 provides reductant-comprising liquor from a source not shown to padder pan 3 to the extent that the level is not maintained by expressed liquor as hereinafter described.
Textile web 1 passes over guide rolls 8 for a time sufficient for the vat dye to be reduced to the soluble leuco form and in this form to have become fixed on textile web 1. Thereafter textile web 1 passes between rubber coated squeeze rolls 9 whereby to express liquor 10, which returns to padder pan 3 via conduit 11. Textile web 1 thereafter passes out of enclosure 2 through exit 12. Outside enclosure 2, web 1 is normally oxidized, soaped, rinsed and dried according to art processes not shown.
The process has been described in terms of chemical padding of a pigment padded web. The invention process is operable with all such processes wherein a reductant-comprising pad liquor is employed as, for example, in the padding of a leuco vat dye liquor comprising a reductant. The process is operable with all manner of padable textiles comprising materials collectively called herein a textile web. The device of this invention can also advantageously be used with other dye types as hereinafter described.
The art worker employing the chemical pad process of Stott et al and wishing to conserve reductant and reduce effluent, would set the chemical padder squeeze rolls so as to reduce the reductant-comprising liquor content of the web to the minimum, normally about 75% of the weight of the web more or less. The worker would have adjusted the concentration of reductant in the liquor so as to provide to the web an adequate amount of reductant usually about 1% of the weight of the web, of sodium hydrosulfite and an equal weight of sodium hydroxide. Of this amount about 75% will be consumed to reduce the vat dye to the leuco form and through losses, and the rest, which the experience of the trade has shown to be necessary, will remain on the web and will be discharged as effluent during the oxidation, soaping and rinsing steps which follow.
The prudent art worker would not risk spoiling the dyeing by employing less than about 25% excess reductant. He is aware that he does not normally know precisely the stoiciometric amount needed to reduce a particular dye in a particular depth of shade. He also knows that the forward reaction rate is favored by excess reductant and that he cannot accurately compensate for oxidation losses during storage and other losses due for example to small amounts of oxygen in the steam. Considerations such as these have led to the essentially universal practice of employing at least about 25% excess reductant.
According to my invention a substantial proportion of the excess now lost as effluent is saved. In the practice of my invention one applies to the web more or less the art amounts of reductant, for example about 1% sodium hydrosulfite and an equal amount of sodium hydroxide on the weight of the web. However, the reductant-comprising liquor is diluted so that one can apply a volume thereof to the web which is greater than can be expressed by squeeze rollers. After steaming the web, liquor is expressed so as to reduce the proportion of liquor on the web to a minimum. The degree to which savings can be realized on reusing the expressed liquor depends on the amount of reductant liquor the web can retain during its passage through the steamer and the degree to which liquor can be expressed at or near the web exit. In order to apply large volumetric proportions of reductant-comprising liquor to the web squeeze rolls 6 will be set relatively loosely. In some cases it will be preferred to pass the web over one or more bars instead of using squeeze rolls at all, and in other cases neither rolls nor bars will be employed. Normally squeeze rolls 9 will be set to express the maximum practical amount of liquor.
Other equipment arrangements are of course operable. For example, although not preferred, the padder assembly at the web entrance may be placed outside enclosure 2. Also, if desired the padder assembly may be placed entirely within enclosure 2, web 1 entering enclosure 2 through a slot. Also squeeze rolls 9 may be set outside enclosure 2 and expressed liquor 10 in combination with a guide roll can serve as a liquid seal in a manner analogous to the drawing arrangement of the padder assembly at the entrance of the steamer.
FIG. 2 shows graphically the relationship between "Liquor Ratio" and realizable savings in percent of the excess reductant employed. "Liquor Ratio" is the ratio of the weight of liquor on a unit length of web after application of liquor at or near the web entrance and the weight of liquor on the web after expression of liquor at or near the web exit. Savings are expressed as percent of the excess which is saved. As is seen, the higher the "Liquor Ratio" the greater the savings.
The practically realizable ratio will depend on the construction of the web. A value of about four is normally about the maximum realizable, for example with towelling.
Although my invention has been exemplified with sodium hydrosulfite reductant, it is clear that other reductants are operable such as those taught by Etters in U.S. Pat. No. 3,645,665.
Ancillary savings also result from the practice of my invention. For example, it follows that a decrease in the amount of reductant passed to the art oxidation step results in a lesser oxidizing agent requirement. Also in those cases wherein dye-fiber equilibrium is not reached during steaming in embodiments comprising either chemical padding, leuco dye padding or equivalent application to the web, savings in dye are realized by virtue of the effectively longer time of fiber-dye contact.
In those cases where equilibrium is not reached savings of other types of substantive dyes such as sulfur, direct and acid dyes can be achieved using the equipment of this invention. Normally condensation of steam on the web is not extensive. To the degree that it occurs, savings are increased over those herein above set out. | Savings in reductant are realized and effluent is reduced in the continuous process of steam fixing of vat dyes on textile web by expressing reductant-comprising liquor containing excess reductant from the web following the steam fixing step and applying expressed liquor, together with fresh reductant liquor, to web entering the fixing step. | 3 |
FIELD
[0001] Most of the embodiments of the disclosure relate generally to a method of classifying arrhythmias in implantable medical devices, and more particularly, to a method and apparatus for discriminating atrial fibrillation from atrial flutter using a measure of variability of a cardiac rhythm parameter.
BACKGROUND
[0002] A variety of techniques have been developed for collecting and interpreting data concerning the electrical activity of the heart. Some techniques use external medical devices (EMDs) in the clinical setting, and others use implantable medical devices (IMDs).
[0003] Implantable cardiac monitors, such as the MEDTRONIC® Reveal™ insertable loop recorder, have also been developed and clinically implanted that employ the capability of recording cardiac electrogram (EGM) data for subsequent interrogation and uplink telemetry transmission to an external programmer for analysis by a medical care provider. The recorded data may be retrieved using an external programmer operated by a medical care provider. The programmer may include the ability to display the retrieved EGM data and/or perform processing and analysis functions on the retrieved EGM data. Stored segments of data can be transmitted via telemetry transmission to an external device for further analysis when a telemetry session is initiated. Aspects of the Reveal™ insertable loop recorder are disclosed in commonly assigned PCT publication WO98/02209 and in U.S. Pat. No. 6,230,059, the disclosures of which are hereby incorporated by reference in their entirety.
[0004] Scatter-plots, sometimes referred to as Lorentz or Poincaréplots, have been used to plot EGM and electrocardiograph (ECG) data. For example, U.S. Pat. No. 5,622,178 issued to Gilham describes a system and method for dynamically displaying cardiac interval data using scatter-plots. Consecutive R-R intervals form a coordinate pair (e.g., the “x” and “y” coordinates) of a point that is plotted on the scatter-plot. Subsequent points are plotted by “sliding” one heartbeat to the next group of successive heartbeats (i.e., the second, third, and fourth heartbeats) and plotting the next pair of R-R intervals. FIG. 1 illustrates an example of this technique in plotting R-R interval data on a scatter plot. Such scatter-plots may provide a visual indication of the variability of the parameter plotted.
[0005] Published Patent Application No. 2002/0065473 compares a number of consecutive R-R interval differences with a predetermined value to measure ventricular rate stability as part of a method to detect atrial fibrillation. A counter is incremented every time the measured R-R interval difference exceeds a threshold value, and classifies a rhythm as AF when a threshold total number is reached. Published Patent Application No. 2004/0092836 discloses an AF detection algorithm that uses a Cluster Signature Metric (CSM) that is based on the two-dimensional distribution of “first order lag” of R-R interval differences. Each of the above references is incorporated by reference herein in its entirety.
[0006] In atrial fibrillation (AF), the atria depolarize at an elevated rate that is highly irregular. The irregular nature of the ventricular response during AF is characterized by fluctuations in the intervals between ventricular contractions. In atrial flutter (AFL), the atria beat at an elevated rate that is highly regular, and a certain portion of the atrial depolarizations may be conducted to the ventricles in a predictable pattern. There are many instances where it is desirable to be able to diagnose intermittent spontaneous cardiac arrhythmias, particularly AF and AFL, in ambulatory patients. Atrial rate may serve as a criterion for distinguishing between AFL and AF. For example, AFL (types I and II) may typically occur at rates that can range from about 220 to about 450 bpm, and AF typically occurs at rates greater than about 300 bpm. However, since a significant range of overlap exists between AF and AFL, and since the range of overlap may be even greater in patients taking anti-arrhythmic drugs and/or in elderly patients, a method of distinguishing them that does not rely solely on rate is needed.
[0007] A method and system for performing scatter-plot analysis to classify cardiac rhythms is desired which minimizes computational resource requirements and allows for real-time processing of cardiac signals. A method of using such real-time data to affect therapy selection decisions (e.g., by an IMD) is also desirable.
SUMMARY OF THE INVENTION
[0008] In certain embodiments of the invention, a method of classifying arrhythmias includes the steps of acquiring a cardiac signal; deriving a recurring cardiac rhythm parameter from the cardiac signal and storing the information derived as a series of values; plotting a point on a scatter plot for each pair of successive stored values, the abscissa of each plotted point being equal to a first value of a pair of successive stored values, and the ordinate of each plotted point being equal to a second value of the pair of successive stored values, the scatter plot being divided into a plurality of regions; deriving a measure of variability by counting the number of regions in which one or more points are plotted; and
[0009] comparing the measure of variability to a threshold value to classify the rhythm. In certain other embodiments of the invention, a system for classifying arrhythmias includes a sensor for acquiring a cardiac signal; a processor for deriving a recurring cardiac rhythm parameter from the cardiac signal and storing it as a series of values; a database for plotting a point on a scatter plot for each pair of successive stored values, the abscissa of the point being the first of a pair of successive stored values, and the ordinate of the point being the second of the pair of successive stored values, and wherein the scatter plot is divided into a plurality of regions; a processor for deriving a measure of variability by counting the number of regions in which one or more points are plotted; and a comparator for comparing the measure of variability to a threshold to classify the rhythm.
[0010] In another embodiment of the invention, an implantable medical device for classifying arrhythmias includes sensing means for acquiring a cardiac signal; processing means for deriving a recurring cardiac rhythm parameter from the cardiac signal and storing it as a series of values; plotting means for plotting a point on a scatter plot for each pair of successive stored values, the abscissa of the point being the first of a pair of successive stored values, and the ordinate of the point being the second of the pair of successive stored values, and wherein the scatter plot is divided into a plurality of regions; a processor for deriving a measure of variability by counting the number of regions in which one or more points are plotted; and a comparator for comparing the measure of variability to a threshold to classify the rhythm.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is an example of a scatter plot of R-R interval data.
[0012] FIGS. 2 ( a )-( c ) illustrate a cardiac signal and various cardiac rhythm parameters derived therefrom.
[0013] FIGS. 3 ( a ) and ( b ) illustrate a cardiac signal and a scatter plot derived therefrom in accordance with an embodiment of the invention.
[0014] FIGS. 4 ( a )-( c ) are examples of alternate embodiments of a scatter plot in accordance with embodiments of the invention.
[0015] FIG. 5 is a scatter plot of a cardiac rhythm parameter, the plot having a plurality of regions formed by a linear grid pattern in accordance with an embodiment of the invention.
[0016] FIG. 6 is a scatter plot of the data shown in FIG. 5 , the plot having a plurality of regions formed by a logarithmic grid pattern in accordance with an embodiment of the invention.
[0017] FIG. 7 is a flowchart showing the steps in a process of calculating a measure of variability from a scatter plot in accordance with an embodiment of the invention.
[0018] FIG. 8 is a plot of a measure of variability as a function of time in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
[0019] The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. The drawings depict selected embodiments and are not intended to limit the scope of the invention. It will be understood that embodiments shown in the drawings and described below are merely for illustrative purposes, and are not intended to limit the scope of the invention as defined in the claims.
[0020] FIGS. 2 ( a )-( c ) show examples of various cardiac rhythm parameters derived from a cardiac signal 20 . Cardiac signal 20 may be acquired from an ECG recording or from an EGM signal, for example. Acquiring a cardiac signal from an ECG recording may, for example, include recording electrical signals from sensors (surface leads) placed on the skin of a patient as is known in the art. Acquiring a cardiac signal from an EGM signal typically includes recording electrical signals from one or more sensors (leads) implanted in a patient either within or in relative close proximity to a chamber of a heart. EGM signals may be far-field, showing timing and morphological information associated with the entire heart, similar to that shown by an ECG, or they may be near-field, showing timing and amplitude information of a single area or chamber of the heart.
[0021] One cardiac rhythm parameter often used to analyze heart rhythms is the R-R interval 2 , as shown in FIG. 2 ( a ). Also shown in FIG. 2 ( a ) is an R-R interval 3 between a “normal” R-wave and a PVC 5 . The R-R interval is an example of a recurring cardiac rhythm parameter, since it can be derived or measured on a repeating basis. Other recurring cardiac rhythm parameters that may be useful for analysis include, but are not limited to, the following examples: P-P interval 4 , R-wave amplitude 7 , P-wave amplitude 8 , Q-T interval 11 , and R-wave slope 6 , as shown in FIGS. 2 ( a ) and ( b ). FIG. 2 ( c ) shows one example of a recurring cardiac rhythm parameter, Δ R-R interval 9 , that may be derived from another recurring cardiac rhythm parameter (in this case, from the R-R intervals). Another recurring cardiac rhythm parameter that may be derived from R-R intervals is ventricular rate. Ventricular rate, for example, may be calculated as a function of the R-R interval 2 , using the equation:
Rate vent (bpm)=60,000/( R - R Interval, msec).
[0022] One of ordinary skill in the art would appreciate that other recurring cardiac rhythm parameters may be similarly derived from a cardiac signal 20 and used in accordance with embodiments of the invention, and would therefore fall within the scope of the claimed invention.
[0023] FIG. 3 ( b ) shows an example of a scatter plot 10 derived from the cardiac signal 20 shown in FIG. 3 ( a ). A series of cardiac rhythm parameters 16 , such as R-R intervals, may be derived from the cardiac signal 20 as described above. The scatter plot 10 is formed by plotting points 14 thereon. Each point 14 is characterized by an x-coordinate (abscissa 22 ), and a y-coordinate (ordinate 24 ), as shown. Note that FIG. 3 ( a ) may only show a portion of the cardiac signal 20 corresponding to scatter plot 10 in FIG. 3 ( b ), since FIG. 3 ( a ) is a time plot of cardiac signal 20 , and since FIG. 3 ( b ) is a scatter plot 10 which condenses a large number of points 14 (N=100) corresponding to a large number of R-R intervals into a relatively small plot area.
[0024] To illustrate the plotting of points 14 onto a scatter plot 10 , the series of R-R intervals shown in FIG. 2 ( c ) may be plotted based upon pairs of R-R intervals 31 - 37 as follows: A first point may have an abscissa of 700 msec and an ordinate of 750 msec corresponding to the first pair of R-R intervals 31 , 32 . A second point may have an abscissa of 750 msec and an ordinate of 720 msec corresponding to the second pair of R-R intervals 32 , 33 . Third and subsequent points are plotted following this same pattern. It should be noted that the choice of abscissa as the first value of each pair of values, and of ordinate as the second value of each pair of values, is somewhat arbitrary; the order could be reversed and would provide an equivalent result without departing from the scope of the invention. See FIG. 1 .
[0025] The area of the scatter plot 10 is divided into a plurality of regions 12 . Each region 12 occupies a specified area of scatter plot 10 , as shown in FIG. 3 ( b ). Each point 14 is plotted into one region 12 of the scatter plot 10 . This may necessitate the creation of a rule for determining which region 12 a point 14 falls within in situations where the point 14 is plotted exactly on the boundary between two regions 12 . One such rule may simply be a “round up” rule, whereby a point 14 that falls exactly on a boundary between regions 12 is assigned to the “higher-valued” region, for example up and/or to the right in the scatter plot 10 shown in FIG. 3 ( b ). FIGS. 4 ( a )-( c ) are examples of alternate configurations of regions 12 having a shape that is not rectangular, and which occupy generally curved portions of the scatter plot 10 in accordance with various embodiments of the invention. Note that the size and shape of region 12 can also vary to suit a particular application. For example, the axes of scatter plot 10 need not be linear. FIGS. 5 and 6 , for example, show the same data plotted on scatter plots having linear and logarithmic axes, respectively.
[0026] The determination of a measure of variability of a cardiac rhythm parameter is based on a graphical estimation using a region counting algorithm, as explained below. In FIG. 3 ( a ), the irregular heart rhythm (cardiac signal 20 ) is plotted in scatter plot 10 of FIG. 3 ( b ) based on a sequence of successive values of a cardiac rhythm parameter 16 derived from the cardiac signal 20 . A specified number of plotted points (the “window” of plotted points) is shown plotted using the Lorentz (or Poincaré) scatter-plot technique described above. The window may, for example, be a sliding window of N points, which slides one point at a time. With a sliding window, each additional heartbeat causes a new point to be plotted, and the oldest point to be removed, so that the total number of points plotted remains equal to the window size, N. Of course, the sliding nature of the window does not have to be updated with each additional heartbeat; a window of N points could be plotted at periodic intervals, for example, with or without overlap between successive windows.
[0027] With continued reference to FIG. 3 ( b ), scatter plot 10 is shown divided into a plurality of regions 12 . The regions 12 shown in the particular embodiment of FIG. 3 ( b ) are comprised of rectangular boxes forming a grid pattern throughout the area of scatter plot 10 . As noted above, the regions 12 need not be rectangular or square in shape. The axes of scatter plot 10 shown FIG. 3 ( b ) range from 150 min −1 to 400 min −1 in a linear grid plot, reflecting a range of atrial rates (which may be derived from P-P intervals, for example). It should be noted that the axes of scatter plot 10 need not be linear, nor does it need to reflect rate or interval information. EGM slope and amplitude are examples of other cardiac rhythm parameters that may also be plotted, among other possible cardiac rhythm parameters. FIGS. 5 and 6 reflect the same cardiac rhythm parameter data plotted on linear and logarithmic scatter plots, respectively.
[0028] To provide a measure of the variability of the cardiac rhythm parameter being plotted, a count is made of the number of regions 12 in which at least one point is plotted. Thus, the variability of the cardiac rhythm parameter may be represented as a number, equal to the number of regions counted containing one or more plotted points. Optionally, the variability may be expressed as a percentage, for example:
Variability=[# regions with at least 1 point/ N points]×100% Eqn 1:
or
Variability=[# regions with at least 1 point/total # regions ]×100%. Eqn 2:
[0029] In one embodiment of the invention, the counting of regions containing one or more plotted points may be weighted by using a weighting factor. For example, in certain embodiments of the invention, it may be desirable to discount the effect on variability of points that fall in regions that are very close to certain specified areas of the scatter plot (areas that tend to have a high concentration of points plotted therein, for example). It may likewise be desirable to increase the effect on variability of points that fall in regions that tend to have a low concentration of plotted points. Thus, a weighting factor may be assigned to each region based upon its location within the scatter plot to thereby affect the measurement of variability.
[0030] FIG. 8 shows a plot of variability over time, with each point plotted corresponding to a measured value of variability (percentage variability is shown in FIG. 8 ). As noted above, each measured value of variability is calculated based upon a window of N points. The window may “slide” one point at a time, or may be based on windows of N points that are “staggered” from one another by a specified number of points or by a specified amount of time, for example. FIG. 8 indicates a threshold 40 (dashed line) for differentiating types of arrhythmias based upon the measure of variability. In some embodiments of the invention, additional thresholds (such as threshold 42 ) may also be used to further refine the arrhythmia classification. A measured variability that is above a specified threshold, for example, may be used to identify an atrial arrhythmia as AF rather than AFL. In one embodiment of the invention, rate information may be used in conjunction with a comparison of the measure of variability to a threshold. For example, an atrial rate of 350 bpm may be classified as either AF or AFL based on rate information alone. A variability that is above a specified threshold may indicate or confirm the presence of AF, while a variability that is below a specified threshold may indicate or confirm the presence of AFL according to certain embodiments of the invention.
[0031] In FIG. 3 ( b ), 100 points are plotted in scatter plot 10 based upon a series of P-P intervals converted into atrial rate information in this example. Scatter plot 10 is divided into a plurality of regions 12 . In this particular example, the regions 12 are formed by grid lines arranged on scatter plot 10 such that the spacing between grid lines corresponds to a change in atrial rate of 16 beats per minute (min −1 ). Each region 12 therefore occupies a space of 16×16 min −1 . The number of regions 12 containing one or more plotted points 14 is then counted to obtain a measure of variability. In FIG. 3 ( b ), for example, a total of 33 regions 12 have one or more points 14 plotted therein. In percentage terms, the resulting measure of variability may be stated as 33%, since the total number of plotted points 14 is 100.
[0032] The process followed in calculating the measure of variability is generally summarized in FIG. 7 , which defines the following steps:
1. Choose a cardiac rhythm parameter (e.g., P-P interval). 2. Select region size/shape and window size, N. 3. Acquire and store cardiac rhythm parameter in a database. 4. Plot cardiac rhythm parameter in a scatter plot until N points are plotted. 5. Calculate measure of variability by counting the number of regions containing one or more plotted points. 6. (Optional) Calculate percent variability. 7. Compare variability to a threshold to classify the rhythm. 8. (Optional) Repeat variability calculation over time.
[0041] The variability of the cardiac rhythm parameter is determined by “drawing” a Lorentz plot of a number of preceding heart beats (window size) onto a scatter plot having a certain region or grid size and shape (resolution). Varying the window size and/or region size/shape may have an influence on the calculated variability.
[0042] In FIG. 3 ( b ), a total of one hundred points 14 were plotted, corresponding to a window size (or width) of 100 (N=100). The choice of N may reflect a trade-off between the desire for calculational simplicity (or speed), and the desire for accuracy or stability. For example, a smaller window N may provide a result sooner (i.e., not as many beats are required, and less memory storage may be needed). A smaller window N may also reflect changes in the measured variability sooner, since the window will not be as heavily weighted with “old” plotted points 14 . A smaller window N may also tend to reflect information that is more local or transient in nature. A larger window N, by contrast, while possibly requiring larger memory storage and computational resources, may tend to produce a measured variability that is more “stable,” since it is “averaging” a larger quantity of data into a numerical result. A larger window may also tend to reflect information that is more global in nature.
[0043] The “grid” (or region) resolution in the example of FIG. 3 ( b ) was based upon a linear, square-shaped region having 16×16 min −1 dimensions. The resolution may be affected by the choice of size and shape of the regions used. For example, a choice of larger regions may result in a smaller number of regions containing one or more plotted points, thereby resulting in a lower measure of variability, according to Eqn. 1. (Note: The variability measured by Eqn. 2 may be smaller, larger, or may be unaffected by changing the size of the regions.) Conversely, selecting smaller regions may result in more regions being counted, thereby producing a higher measure of variability, according to Eqn. 1.
[0044] The selections of window size N and region size and/or shape may be affected by a variety of factors, such as the particular cardiac rhythm parameter being analyzed, patient history, known sensing issues (FFRWs, undersensing), etc. The selections regarding window size and region size/shape may also be affected by the rate/interval of the particular cardiac rhythm parameter or of the overall heart rate of the patient. In one embodiment of the invention, a calculation of rate/interval is made in conjunction with the variability measurement. The rate/interval may be an average rate based upon a certain number of beats, R; the number of beats R used to calculate rate may also be a parameter that can be selected and varied in accordance with certain embodiments of the invention.
[0045] It should be noted that physically “drawing” or “plotting” the scatter plot 10 is not a required step. For example, the process of plotting points in a scatter plot may be performed by a memory device and logic circuitry and/or software instructions that are capable of identifying and recording which region 12 a point would fall into, and incrementing (and decrementing) counters to keep track of the points 14 that fall within each of the regions 12 . (Decrementing of a counter would occur, for example, when the sliding window of N points causes the oldest point 14 to be removed from the window, and hence, from the affected region 12 .) Each region 12 may, in such an embodiment, comprise a data bin for storing the number of points 14 that fall within a region, based on logic circuitry and counters, for example. Additional logic circuitry and/or a counter may determine the measure of variability by counting the total number of data bins that has one or more points stored therein.
[0046] The methods of classifying arrhythmias disclosed herein are relatively simple to implement, and may be performed by an Implantable Medical Device (IMD). For example, the steps of plotting points and counting regions can be accomplished with logic circuitry such as comparators, counters, and memory. Calculating percent variability may require additional components and/or instructions capable of performing division, for example. Comparing the measured variability to a threshold may also require a comparator. All of these functions may be incorporated in the circuitry of an IMD, and may further be performed in real-time, e.g., to select and/or deliver an appropriate therapy based upon the arrhythmia classification. The advantages in computational simplicity described above typically result in a reduced need for memory and processing power, which may result in reduced battery capacity requirements, reduced memory storage requirements, smaller device sizes, faster responses, etc.
[0047] The region-counting approach to measuring variability of a cardiac rhythm parameter may also be less sensitive to certain sensing problems like far-field R-waves (FFRWs) and undersensing. Due to the typically repetitive (regular) nature of FFRWs and 2:1 blanking, for example, these beats typically end up plotted into a fairly small number of regions in the Lorentz plot and therefore may not significantly affect the measured variability. Additionally, certain sensing problems (such as severe undersensing) may not be reflected, for example, if the Lorentz plot only plots events above (or below) a certain amount (e.g., only atrial rates greater than 100 min−1). In other words, even if certain sensing problems exist, they may not have a significant effect on the measurement of variability.
[0048] Thus, embodiments of a METHOD OF AND APPARATUS FOR CLASSIFYING ARRHYTHMIAS USING SCATTER PLOT ANALYSIS are disclosed. One skilled in the art will appreciate that the invention can be practiced with embodiments other than those disclosed. The disclosed embodiments are presented for purposes of illustration and not limitation, and the invention is limited only by the claims that follow. | A method of classifying arrhythmias using scatter plot analysis to define a measure of variability of a cardiac rhythm parameter such as for example, without limitation, R-R interval, A-A interval, and the slope of a portion of a cardiac signal, is disclosed. The variability measurement is derived from a scatter plot of a cardiac rhythm parameter, employing a region counting technique that quantifies the variability of the cardiac rhythm parameter while minimizing the computational complexity. The method may be employed by an implantable medical device or system, such as an implantable pacemaker or cardioverter defibrillator, or by an external device or system, such as a programmer or computer. The variability measurement may be correlated with other device or system information to differentiate between atrial flutter and atrial fibrillation, for example. The variability information may also be used by the device or system to select an appropriate therapy for a patient. | 8 |
FIELD
The present invention relates to toilets. More particularly, the present invention relates to a toilet actuation apparatus for actuating at least one of a toilet lid, a toilet seat and a flush lever using foot-actuated pedals.
BACKGROUND
A conventional toilet includes a toilet bowl on which is pivotally mounted a toilet seat and a toilet lid. A water tank provided on the toilet bowl includes a typically hand-actuated flush lever. The toilet lid and toilet seat can be selectively raised and lowered manually. Many persons have concerns regarding manual operation of a toilet due to the potential for germ contamination.
SUMMARY
The present invention is generally directed to a toilet actuation apparatus. An illustrative embodiment of the apparatus includes a lever support, at least one pedal lever pivotally carried by the lever support, at least one pedal carried by the at least one pedal lever on a first side of the lever support, at least one actuation lever pivotally carried by the at least one pedal lever on a second side of the lever support, at least one toothed actuation rack carried by the at least one actuation lever and at least one toothed actuation pinion engaging the at least one toothed actuation rack.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a front perspective view of an illustrative embodiment of the toilet actuation apparatus, fitted to a toilet, with the toilet seat and toilet lid shown in a lowered position;
FIG. 2 is a front perspective view of an illustrative embodiment of the toilet actuation apparatus, fitted to a toilet, with the toilet lid shown in a raised position;
FIG. 3 is a sectional view, taken along section lines 3 - 3 in FIG. 1 ;
FIG. 4 is a sectional view, taken along section lines 4 - 4 in FIG. 2 ; and
FIG. 5 is a sectional view of an enclosure component of an illustrative embodiment of the toilet actuation apparatus, more particularly illustrating an exemplary technique which facilitates raising and lowering of a toilet seat and toilet lid on the toilet.
DETAILED DESCRIPTION
Referring to the drawings, an illustrative embodiment of the toilet actuation apparatus, hereinafter apparatus, is generally indicated by reference numeral 1 . As shown in FIGS. 1-4 and will be hereinafter described, the apparatus 1 is adapted to operate a toilet 34 which may be conventional. The toilet 34 typically includes a toilet bowl 35 . A toilet seat 36 has a toilet seat axle 37 , and a toilet lid 38 has a toilet lid axle 39 , which are pivotally attached to the toilet bowl 35 . A water tank 42 is provided on the toilet bowl 35 and is fitted with a flush lever 43 .
The apparatus 1 includes an enclosure 2 . In some embodiments, the enclosure 2 has a base portion 3 and an extended portion 4 which extends from the base portion 3 , in generally perpendicular relationship thereto. As shown in FIGS. 3 and 4 , the enclosure 2 has an enclosure interior 5 .
As shown in FIGS. 3 and 4 , a lever support 30 is provided in the enclosure interior 5 of the base portion 3 . As shown in FIG. 4 , in some embodiments an elongated lid pedal lever 9 is pivotally attached to the lever support 30 at a pivot point 31 . The lid pedal lever 9 extends through a lever slot (not shown) provided in the base portion 3 of the enclosure 2 , where a lid pedal 8 is provided on the lid pedal lever 9 . As further shown in FIG. 4 , an elongated lid actuation lever 10 is pivotally attached to the lid pedal lever 9 and extends through the enclosure interior 5 of the extended portion 4 . A toothed lid actuation rack 11 extends from the lid actuation lever 10 . As shown in FIG. 5 , a toothed lid actuation pinion 12 is provided on the toilet lid axle 39 . A toothed lid guide pinion 13 is rotatably attached to the enclosure 2 adjacent to the lid actuation pinion 12 . The lid actuation rack 11 extends between and meshes with the lid actuation pinion 12 and the lid guide pinion 13 . Accordingly, upon depression of the lid pedal 8 , the lid pedal lever 9 ( FIG. 4 ) pivots with respect to the pivot point 31 and raises the lid actuation lever 10 in the enclosure interior 5 . The lid actuation rack 11 rotates the lid actuation pinion 12 , which in turn rotates the toilet lid axle ( FIGS. 1 and 2 ). This facilitates lifting of the toilet lid 38 from the closed position shown in FIG. 1 to the raised position shown in FIG. 2 . Conversely, release of the lid pedal 8 facilitates lowering of the toilet lid 38 back to the closed position in FIG. 1 , typically by the falling action of the toilet lid 38 , as the lid actuation pinion 12 rotates in the opposite direction; the lid actuation rack 11 is lowered between the lid actuation pinion 12 and the lid guide pinion 13 ; and the lid pedal lever 9 pivots back to the original position in the enclosure interior 5 .
As further shown in FIG. 4 , in some embodiments an elongated seat pedal lever 17 is pivotally attached to the lever support 30 at the pivot point 31 . The seat pedal lever 17 extends through a lever slot (not shown) provided in the base portion 3 of the enclosure 2 , where a seat pedal 16 is provided on the seat pedal lever 17 . As further shown in FIG. 4 , an elongated seat actuation lever 18 is pivotally attached to the seat pedal lever 17 and extends through the enclosure interior 5 of the extended portion 4 . A toothed seat actuation rack 19 extends from the seat actuation lever 18 . As shown in FIG. 5 , a toothed seat actuation pinion 20 is provided on the toilet seat axle 37 . A toothed seat guide pinion 21 is rotatably attached to the enclosure 2 adjacent to the seat actuation pinion 20 . The seat actuation rack 19 extends between and meshes with the seat actuation pinion 20 and the seat guide pinion 21 . Accordingly, upon depression of the seat pedal 16 , the seat pedal lever 17 ( FIG. 4 ) pivots with respect to the pivot point 31 and raises the seat actuation lever 18 in the enclosure interior 5 . The seat actuation rack 19 rotates the seat actuation pinion 20 , which in turn rotates the toilet seat axle 37 ( FIGS. 1 and 2 ). This facilitates lifting of the toilet seat 36 from the closed position shown in FIG. 4 to a raised position (not shown). Conversely, release of the seat pedal 16 facilitates lowering of the toilet seat 36 back to the closed position, typically by the falling action of the toilet seat 36 , as the seat actuation pinion 20 rotates in the opposite direction; the seat actuation rack 19 is lowered between the seat actuation pinion 20 and the seat guide pinion 21 ; and the seat pedal lever 17 pivots back to the original position in the enclosure interior 5 .
As shown in FIG. 3 , in some embodiments an elongated flush pedal lever 25 is pivotally attached to the lever support at the pivot point 31 . The flush pedal lever 25 extends through a lever slot (not shown) provided in the base portion 3 of the enclosure 2 , where a flush pedal 24 is provided on the flush pedal lever 25 . As further shown in FIG. 4 , an elongated flush actuation lever 26 is pivotally attached to the flush pedal lever 25 and extends from the enclosure interior 5 of the extended portion 4 through a lever slot (not shown). The distal or extending end of the flush actuation lever 26 is attached to the flush lever 43 of the toilet 34 according to the knowledge of those skilled in the art. Accordingly, upon depression of the flush pedal 24 , the flush pedal lever 25 pivots with respect to the pivot point 31 and raises the flush actuation lever 26 , thereby actuating the flush mechanism (not shown) in the water tank 42 . Upon release of the flush pedal 24 , the flush pedal lever 25 pivots back to the original position and lowers the flush actuation lever 26 .
In typical use of the apparatus 1 , the lid pedal 8 is actuated to selectively raise and lower the toilet lid 38 ; the seat pedal 16 is actuated to selectively raise and lower the toilet seat 36 ; and the flush pedal 24 is actuated to selectively actuate the flush lever 43 of the toilet 34 . This renders unnecessary manual contact of the toilet lid 38 , toilet seat 36 and/or flush lever 43 by the user (not shown) of the toilet 34 .
While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications can be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention. | A toilet actuation apparatus. An illustrative embodiment of the apparatus includes a lever support, at least one pedal lever pivotally carried by the lever support, at least one pedal carried by the at least one pedal lever on a first side of the lever support, at least one actuation lever pivotally carried by the at least one pedal lever on a second side of the lever support, at least one toothed actuation rack carried by the at least one actuation lever and at least one toothed actuation pinion engaging the at least one toothed actuation rack. | 0 |
FIELD OF THE INVENTION
The invention indicates a microfluidic structure for the combining of liquid volumes, as well as a microfluidic system with such a microfluidic structure.
BACKGROUND OF THE INVENTION
Microfluidic systems were already the subject of biotechnology research and development in past years and are being used increasingly in the form of so-called lab-on-a-chip systems etc., also for medical diagnosis in point-of-care products. The terms microfluidic system and lab-on-a-chip are used here as synonyms. On these microfluidic chip systems, protocols previously worked out in the laboratory are converted as completely as possible into a microfluidic structure on the lab-on-a-chip, so that the protocols are largely automated and take place with the least possible manual intervention. The chip systems are generally used with operator devices, while the operator devices are outfitted with a holder for the chip as well as electrical, fluidic and actuator interfaces for the chip, if needed.
The microfluidic systems contain various microfluidic structures with size dimensions in the micrometer range, while individual microfluidic structures, especially fluid chambers or fluid reservoirs, can also have larger cross sections in the millimeter range. Often the microfluidic systems are formed by a base plate in which channels and depressions are fashioned, and a cover foil enclosing the channels and depressions. The base plates are molded from plastic by injection molding or embossing and the cover foils are joined fluid-tight to the base plates by gluing or welding. Modular microfluidic systems made of several planar and/or blocklike microfluidic modules are also known, such as the publication of Drese, K.; von Germar, F.; Ritzi, M.: “Sample preparation in Lab-on-a-Chip systems—Combining modules to create a fully integrated system”, in: Medical Device Technology 18 (2007) 1, 42-47. These individual modules are coupled together by suitable connections so as to realize various process pathways, depending on the stated goal.
An often occurring process operation within microfluidic systems is the combining of different fluid volumes. Various solutions already exist for this.
The publication of Götz Münchow, Dalibor Dadic, Frank Doffing, Steffen Hardt, Klaus-Stefan Drese, “Automated chip-based device for simple and fast nucleic acid amplification”, in Expert Rev. Mol. Diagn. 5 (4), (2005), indicates in FIG. 7 and the accompanying description (page 616, left column) a microfluidic structure for the combining of two liquid volumes. The Y-shaped structure for this has two inlet lines coming together at an acute angle, which are joined in a channel. In the region where the inlet lines discharge into the channel the inlet lines are narrowed in cross section. The liquids being combined are introduced into the inlet lines and move by capillary forces as far as the narrowed points of the inlet lines, but halt at the end of these points before entering the channel with the broader cross section. Only when a pressure pulse is applied to at least one inlet line can the capillary force preventing the liquid from moving into the channel be overcome and trigger the combining of the liquids in the channel.
In European patent application EP 1 932 593 A1 a microfluidic structure is indicated for the combining of liquids, in which an inlet line for a first fluid empties into a channel. The first liquid is kept ready in a reservoir joined to the inlet line and open to the surroundings and it flows by capillary forces up to the point where the inlet line empties into the channel. The first liquid is taken up by a second liquid, which is also carried in the channel by capillary forces. Important to this type of fluid control is the correct matching of the capillary forces operating in channel, feed opening and reservoir by structure sizes, as well as surface quality. Furthermore, a ventilation of the reservoir is required.
By microfluidic structures and systems according to the indicated invention are meant those systems and structures whose fluid channels have cross section dimension with magnitudes in at least one direction perpendicular to the direction of flow in the range of 10 μm to 2000 μm and especially preferably in the range of 25 μm to 1500 μm. The liquid volumes stored and delivered in these microfluidic systems and structures are in the nanoliter to several-digit microliter range in the case of small volumes, and in the milliliter range in the case of larger volumes.
Pressure-operable or pressure-operated in the sense of the invention's microfluidic systems or structures means that liquid volumes in the microfluidic systems or structures of the invention are driven or can be driven by a delivery pressure acting from outside the microfluidic system or microfluidic structure, such as one generated by a syringe pump. A passive drive, especially a drive acting solely through capillary forces, is not possible or specified for the microfluidic systems or structures of the invention since the cross sectional dimensions of the microfluidic structures in the microfluidic systems of the invention are so large, at least in sections, or the surface textures of the microfluidic structures are configured such that not enough capillary pressure is formed there for reliable delivery of liquid by the microfluidic systems.
On the other hand, capillary driving of the liquids is also possible in individual sections of the microfluidic systems of the invention.
In alternative embodiments; a driving of liquid volumes by making use of magnetorheological liquids or ferrofluids can also be used in the microfluidic systems or structures of the invention. In this case, plugs of a magnetorheological liquid or a ferrofluid are placed in the direction of flow upstream or downstream of the liquid volumes being delivered in the channels or structures of the microfluidic system. A driving of the plugs and the liquid volumes connected with them is done by magnets moved parallel to the fluid structures. In another variant of this type of propulsion, a plug of a magnetorheological liquid or a ferrofluid is moved in a channel section of larger cross section and produces by its movements a delivery pressure in a channel of smaller cross section, fluidically connected to the former channel. Thanks to the different cross sectional sizes of the channels, a large delivery power can be achieved in the channels of smaller cross section with short displacements of the magnets. In the case of an equally possible reversed relationship of cross sectional sizes, a very position and/or pressure-precise delivery can be achieved in the channels of smaller cross section.
SUMMARY OF THE INVENTION
The problem on which the invention is based is to indicate a simple microfluidic structure for the bubble-free combining of liquid volumes and a lab-on-a-chip with such a microfluidic structure.
The problem is solved by a microfluidic structure for the bubble-free combining of two liquid volumes comprising a fluid chamber, which has a feed opening, as well as an inlet and outlet channel emerging into the fluid chamber, wherein the fluid chamber has a cross section that broadens out relative to the inlet channel in a direction of flow from the inlet to the outlet channel and is designed, thanks to the broadened cross section, to broaden a first liquid volume that is essentially pressure-driven and conducted through the inlet channel and through the fluid chamber to a cross section at least approximately corresponding to the full cross section of the fluid chamber, wherein the fluid chamber has a holding position and is designed such that a second liquid volume, placed in the fluid chamber through the feed opening, can be held in the region of the holding position and wherein the second liquid volume when the first liquid volume is moved through by pressure can be taken up by the latter and delivered as a combined liquid volume through the fluid chamber and into the outlet channel and a lab-on-a-chip comprising at least one microfluidic structure wherein the lab-on-chip additionally has several other channels, chambers and/or reservoirs.
The pressure-operable microfluidic structure of the invention for the bubble-free combining of a first and a second liquid volume has a fluid chamber with a feed opening, as well as an inlet and outlet channel emerging into the fluid chamber.
The fluid chamber has a cross section that broadens out relative to the inlet channel in the direction of flow from the inlet to the outlet channel and is designed, thanks to the broadened cross section, to broaden a first liquid volume that is essentially pressure-driven and conducted through the inlet channel and through the fluid chamber to a cross section at least approximately corresponding to the full cross section of the fluid chamber, i.e., at least 75%, preferably 95% of the cross section area, during its entire flow through the fluid chamber.
The fluid chamber has a holding position for a second liquid volume. The holding position is configured so that a second liquid volume, placed in the fluid chamber through the feed opening, can be held in the region of the holding position so that only a portion of the fluid chamber cross section is filled up, and the second liquid volume when the first liquid volume is moved through by pressure is taken up by the latter and delivered as a combined liquid volume through the fluid chamber and into the outlet channel.
In the case of small second liquid volumes, the contact surfaces forming between the small second liquid volume and the fluid chamber are already enough to serve as holding structures to form a limited holding position, especially contact surfaces with the bottom, top, and one wall surface of the fluid chamber in the region of the feed opening. Preferably, the holding position for the second liquid volume is formed in a region of the fluid chamber with at least one at least partly curved and/or at least partly trough-shaped wall, bottom and/or top surface as a holding structure. The curvature and/or trough increases the contact surface between the second liquid volume and fluid chamber and larger holding forces are produced. This is preferably a curvature or trough of a surface formed locally in the region of the holding position.
A microfluidic structure according to the invention enables a secure operation, scarcely prone to errors, and an economical fabrication, thanks to the simple, undemanding configuration. The inclusion of air bubbles in the combined liquid volume is securely prevented with a simpler manner of combining the liquid volumes in the microfluidic structure.
The surfaces of the channels and the fluid chamber of the microfluidic structure and/or the lab-on-a-chip of the invention can be designed to be wettable through the choice of material and/or manufacturing process. However, coatings or other processes which render the surface wettable are also possible. Wettable means, in the case of a microfluidic structure for aqueous solutions, choosing a pronounced hydrophilic surface with a contact angle of more than 0° to less than 90°, or preferably with a contact angle of 5° to 70°. In the case of very low contact angle, there is a risk of the liquid creeping along the surfaces and channels. In the case of microfluidic structures for organic, nonpolar liquids, pronounced lipophilic surfaces are preferred.
Thanks to the surfaces of the microfluidic structure according to the invention that have been made wettable in the mentioned way, the first liquid upon flowing through the fluid chamber is stretched in contact with the wall, bottom and top surfaces across the full cross section of the fluid chamber, and no possibly gas-permeable intermediate space is formed between first liquid and wall, bottom and top surfaces as it flows through the fluid chamber.
The hydrophilic or lipophilic treatment can be done in known fashion by a dipping method, as described in DE 100 13 311 C2, or by a coating process. For example, polycarbonate, a slightly hydrophobic material, can be made hydrophilic by an oxygen plasma treatment on the surface.
The polymer material, in which the microfluidic structure of the invention or the lab-on-a-chip is preferably made, is preferably an injection-moldable or (hot) stamped polymer, especially preferably a thermoplastic or an elastic thermoplastic. One can also use one or more of the following materials: acrylate, polymethylacrylate, polymethylmethacrylate, polycarbonate, polystyrene, polyimide, cycloolefin copolymer (COC), cycloolefin polymer (COP), polyurethane, epoxy resin, halogenated acrylate, deuterated polysiloxane, PDMS, fluorinated polyimide, polyetherimide, perfluorcyclobutane, perfluorvinylether copolymer (Teflon AF), perfluorvinylether cyclopolymer (CYTOP), polytetrafluorethylene (PTFE), fluorinated polyarylether sulfide (FRAESI), inorganic polymer glass, polymethylmethacrylate copolymer (P2ANS).
In further embodiments, the microfluidic structure and the lab-on-a-chip according to the invention can also be made from glass, silicon, metal and/or ceramic, depending on the application, and a combination of various of the aforementioned materials can also be used, such as a glass or silicon base plate with channels and chambers worked into it can be covered by polymer foils.
In one preferred embodiment of the invention, the fluid chamber has a cross section widened with respect to the inlet channel by not more than 5 times, especially preferably by not more than 2.5 times. This limited broadening of the fluid chamber relative to the inlet channel ensures that the first liquid volume is broadened to at least approximately the full cross section of the fluid chamber as it flows through the fluid chamber under pressure.
Also the preferred embodiment of the broadening of the inlet channel to the cross section of the fluid chamber in the form of a steady widening, preferably a curvelike widening, without edges or corners, supports the broadening of the first liquid volume to the at least approximately full cross section of the fluid chamber during the entire flow through the fluid chamber.
The fluid chamber has a preferably oblong shape, i.e., its length in the flow direction is greater than its largest cross section dimension of the fluid chamber, especially preferably it is longer by a multiple of the largest cross sectional dimension of the fluid chamber. The inlet and/or outlet channel each emerge into the oblong fluid chamber at a short side or point.
The fluid chamber can also be asymmetrical in the flow direction with broadening only at one end, i.e., for example, with the shape of a triangle, a trapezium or a circular segment in top view, while the inlet and outlet channels each lie in the region of the ends of the longest side or the ends of the chord of the circle.
In further advantageous embodiments of the microfluidic structure of the invention, other structures can be provided in the fluid chamber to support the bringing together of the liquid volumes. For example, in the region where the inlet channel emerges into the fluid chamber there can be a dent curved inwardly into the fluid chamber at one end. A liquid volume flowing into the fluid chamber through the inlet channel will first be conducted only along one wall surface of the fluid chamber and only be widened to the at least approximately full cross section of the fluid chamber downstream from the structure that supports the bringing together of liquids. This configuration of the fluid chamber supports the widening of the first liquid volume to the at least approximately full cross section of the fluid chamber without there being a breakthrough of a delivery gas, for example.
In the case of asymmetrically shaped fluid chambers, the first liquid volume is conducted in this fashion from the wall surface near the inlet channel in the flow direction along the longest side or along the circle chord in a streamline lying centrally in the fluid chamber, so that a less pronounced widening of the liquid volume at both ends can occur along the central flow direction after the structures supporting the bringing together of liquids.
The feed opening and/or holding position for the second liquid volume are preferably arranged off-center in the fluid chamber, i.e., away from a central streamline extending from the inlet channel through the fluid chamber to the outlet channel. In the case of an asymmetrical configuration of the fluid chamber, the feed opening and/or holding position can be arranged in the region of the protrusion at one end of the fluid chamber, likewise away from the central streamline from the inlet to the outlet channel through the fluid chamber.
This configuration prevents a gas flowing through the microfluidic structure from entraining a second liquid volume already placed in the microfluidic structure before the first liquid volume gets to the fluid chamber.
In one preferred embodiment of the invention the feed opening can be closed. With a closed feed opening, the pressure difference prevailing in the pressure-operated propulsion of the liquids can be kept at a lower level and an operation at a pressure lower than the surroundings is possible. The feed opening is designed preferably so that it closes automatically, for example, by placing a septum or an elastic cover foil on it. Sample liquids can therefore be applied as the second liquid volume, without a risk of the sample liquids escaping from the microfluidic structure of the invention. A contamination of the inner spaces of the microfluidic structure of the invention can also be prevented in this way.
In another embodiment, the feed opening can also be designed to be closed by a sealing element which can move relative to the feed opening. The sealing element in this embodiment is part of the microfluidic structure. In event of using a movable sealing element, the sealing element preferably has engaging elements which can be engaged during operation in an operator device by corresponding actuators of the operator device.
Also a configuration of the feed opening that is opened and closed via an operator device is provided in a further preferred embodiment of the microfluidic structure of the invention. For this, the feed opening has a sealing surface, for example, which is in tight fluidic connection with a closable fluid line of an operator device when the microfluidic structure is operating in an operator device, or it can be opened and closed by an active sealing element of the operator device.
The aperture of the feed opening is preferably small, i.e., smaller than 1/20 and especially preferably smaller than 1/100 of the largest cross sectional area of the fluid chamber in the flow direction from the inlet channel to the outlet channel. A small aperture of the feed opening reduces the danger of contamination. If it is not arranged to close the feed opening during operation of the microfluidic structure, there is furthermore no risk of escape of the liquids being delivered in the microfluidic structure when the aperture of the feed opening is small.
The feed opening in another preferred embodiment can also be configured as a channel emerging into the fluid chamber. To assure an unhindered flow through the fluid chamber during operation of the microfluidic structure from the inlet channel to the outlet channel, the cross section of the feed openings in a preferred embodiment is very small in relation to the cross sectional area of the fluid chamber transverse to the direction of flow, preferably less than 1/20. The feed opening can also be made to close in this embodiment.
The fluid chamber can also have several feed openings for adding several second liquid volumes. In this way, more than just two liquid volumes can be combined with each other or the feed amount can also be divided among several feed openings and holding positions.
Preferably one holding position is arranged in the fluid chamber for each feed opening. The second liquid volumes added in this way are only brought together with each other when a first liquid volume has been conducted through the fluid chamber and picks up the second liquid volumes one after another.
In further embodiments, holding structures are configured in the region of the holding positions in addition to the aforementioned structures or also as the sole holding structure. These holding structures, alone or in variously configured combinations of alternative holding structures, assure the secure positioning and fixation of small to rather large second liquid volumes in the microfluidic structure of the invention.
The holding position can have, as holding structures for this, special surface structures such as recesses, surface textures, or one or more steles. For example, changes in the surface energies (contact angles) can be used for localization of the stored drops. Preferably, the contact angle of the second liquid volume with the surface of the holding structure is greater than 0° and less than 90°, especially preferably greater than 5° and less than 70°.
Structures for secure positioning of the second liquid volume at the holding position comprise, in a further embodiment, especially two-sided structures, such as steles on either side of the feed opening in the fluid chamber, since in this way the holding position for the second liquid volume is configured between these steles and additional holding surfaces for the second liquid volume for the fluid chamber can be formed.
Furthermore, different heights of the fluid chamber can be used for secure positioning of the second liquid volume. For this, the fluid chamber is configured lower in the region of the holding position than in the rest of the fluid chamber, so that the second liquid volume has a contact with bottom, top and side wall of the fluid chamber in the region of the holding position.
In further embodiments, surface roughness of the walls of the fluid chamber is used as holding structures in the region of the holding position to support hysteresis effects, in order to support a secure positioning of the second liquid volume.
The holding position occupies only a portion of the fluid chamber's cross section, so that the entire cross section of the fluid chamber is not blocked. The limiting of the holding position to partial regions of the fluid chamber can be supported by the corresponding local limited configuration of holding structures in the region of the holding position.
In microfluidic systems consisting of a base plate with cover foil, the so-called lab-on-a-chip, the feed openings are preferably configured as a hole above the fluid chamber in a cover foil. In a further embodiment, however, the feed openings can also be fashioned as openings in the bottom and/or side surfaces of the fluid chamber in the base plate.
In another embodiment of the microfluidic structure of the invention, several fluid chambers with feed openings are arranged one behind another. This embodiment enables the sequential combining of liquids. Thus, reactions can be carried out in succession.
The microfluidic structure of the invention in other embodiments can also have additional elements which support a widening and flowing through the fluid chamber, for example, to almost the full cross section of the fluid chamber, possibly with total wetting of the wall, bottom and top surface of the fluid chamber in the manner of the invention, for example, steady narrowings of the cross section on one or more sides at the transition from the inlet channel to the fluid chamber.
In another embodiment of the invention, after the combining of the liquid volumes and their issuing through the outlet channel it is also possible to reverse the direction of flow of the combined liquid volumes.
The invention also comprises a lab-on-a-chip with at least one microfluidic structure according to one of the indicated embodiments, wherein the lab-on-chip additionally has several other channels, chambers and/or reservoirs. The lab-on-a-chip of the invention is therefore suitable for carrying out several consecutive process steps including the bubble-free combining of two liquid volumes in the microfluidic structure of the invention.
Such a lab-on-a-chip can be filled already with certain chemicals in some chambers and/or reservoirs during the course of its manufacture. In operation, the sample being processed is then placed through the feed opening into the lab-on-a-chip and a process chain is worked off through a suitable set of actuators in the operator device, making use of the chemicals already stored on the chip.
The lab-on-a-chip can have the microfluidic structures of the invention once or more times in a consecutive or parallel arrangement in the direction of flow of the fluids, so that sequential or parallel combining of liquid volumes can also occur. In the case of the sequential arrangement, reaction sequences can be worked off in the lab-on-a-chip. In a parallel arrangement, process chains running in parallel can be worked off on a single chip.
The invention is not limited to the above described embodiments and the following sample embodiments, but rather also covers new combinations of features, formed from the basic notions of the invention as indicated in claim 1 or claim 18 , and individual features and combinations of features of the preferred embodiments and the sample embodiments.
In the following sample embodiments, for the most part only the microfluidic structures of the invention are depicted, fashioned as trenches and depressions in a base plate and covered with a foil. However, the microfluidic structure of the invention constitutes only one part of the structures in the overall system, i.e., besides the microfluidic structure of the invention other elements are also contained in these systems, such as channels, chambers, reservoirs, actuators, etc., and they interact structurally or functionally with each other.
BRIEF DESCRIPTION OF THE DRAWINGS
Individual sample embodiments are presented hereafter:
FIG. 1 : Schematic representation of a microfluidic structure of the invention in top view with three alternative embodiments of the microfluidic structure;
FIGS. 2 a to 2 c : Schematic representation of the process of combining of liquid volumes in a microfluidic structure of the invention;
FIG. 3 : Schematic representation of the consecutive sequence of two microfluidic structures of the invention in top view;
FIG. 4 : Schematic representation of the parallel arrangement of two microfluidic structures of the invention in top view;
FIGS. 5 a to 5 d : Representation of the cross section of three microfluidic structures according to the invention;
FIG. 6 : Schematic representation of a microfluidic structure of the invention in top view with holding structures in the region of the holding positions in top view;
FIG. 7 : Schematic representation of a microfluidic structure of the invention in the region of a dead-end channel in top view;
FIG. 8 : Schematic representation of a microfluidic structure of the invention with a structure promoting the combining of liquid volumes in top view;
FIG. 9 : Lab-on-a-chip/microfluidic system for carrying out a PCR reaction in top view.
DETAILED DESCRIPTION OF THE INVENTION
In the figures, liquid boundary surfaces of the liquid volumes 41 , 42 , 43 , 141 are shown in the form of broken lines. In the sample embodiment with a figure in top view, the cover foil is not indicated. In these figures, only the base plate with the contours of the channels and chambers is shown. The direction of flow of the fluids is indicated by black arrows.
In FIG. 1 , three different embodiments of the microfluidic structure 1 of the invention are shown schematically. The structures such as fluid chamber 2 , inlet line 3 and outlet line 4 , as well as feed openings 5 , are in this case formed as groovelike depressions and/or recesses in a base plate 10 and enclosed by a cover foil 11 (not visible in the figures, except for FIGS. 5 a to 5 d ). The cross sections in the sample embodiment shown here have a rectangular shape transversely to the direction of flow, but in addition other cross sectional shapes such as semicircles are also possible.
In the first alternative embodiment of the microfluidic structure 1 of the invention, in FIG. 1 , left, an asymmetrically shaped fluid chamber 2 is shown, being roughly in the shape of a circle segment in this sample embodiment. The feed opening 5 made in the base plate, as well as the holding position 6 for the second liquid volume 42 , is situated in the region of the widening of the fluid chamber 2 near or already in contact with the side wall surface 21 of the fluid chamber, away from the shortest flow path through inlet channel 3 , fluid chamber 2 and outlet channel 4 , in order to prevent the second liquid volume 42 present in the fluid chamber 2 from being entrained by a gas flow.
Thanks to the proximity of the feed opening 5 and/or holding position 6 to the side wall surface 21 of the fluid chamber 2 , the second liquid volume 42 can form a larger contact area with the curved wall surface 21 of the fluid chamber 2 as a holding structure 7 and thereby be held more securely at the holding position 6 .
In the second, middle, sample embodiment of FIG. 1 , a symmetrically shaped fluid chamber 2 is shown; the feed opening 5 here as well lies underneath the fluid chamber 2 in the base plate 10 , not in the region of the side wall surface 21 of the fluid chamber 2 , but rather between a central streamline and the side wall surface 21 of the fluid chamber 2 . The holding position 6 in this instance has a holding structure 7 in the form of a depression 72 in the base plate 10 .
In the third sample embodiment, shown at right in FIG. 1 , an additional channel 31 empties into the fluid chamber 2 across a narrowed feed opening 5 . By this channel 31 , a second liquid volume 42 is placed in the fluid chamber 2 . The channel 31 in this case can be supplied with the second liquid volume 42 by an operator device. Here as well, a holding structure 7 in the form of a depression in the base plate is provided in the region of the holding position 6 .
In operation, a second fluid volume 42 is first placed at the holding position 6 through the feed opening 5 in the microfluidic structure 1 of the invention, as shown in FIGS. 2 a to 2 c . Next, a first liquid volume 41 is placed in the fluid chamber 2 via the inlet channel 3 and propelled by a pressure difference in the direction of the outlet channel 4 . As the first liquid volume 41 is driven by pressure through the fluid chamber 2 , the first liquid volume 41 is broadened out to the full cross section of the fluid chamber, thanks to the wettable surfaces in this case, and coalesces without gas inclusions with the second liquid volume 42 already present in the fluid chamber 2 . The combined fluid volume 41 + 42 finally gets into the outlet channel 4 .
In FIG. 3 , a consecutive sequence of two microfluidic structures 1 , 1 ′ of the invention is shown. In fluid chamber 2 of the first microfluidic structure 1 of the invention, a first liquid volume 41 was already combined with a second liquid volume 42 . During the further passage of the combined liquid volumes 41 + 42 through the second microfluidic structure 1 ′ of the invention, a third liquid volume 43 placed therein at a holding position 6 ′ is likewise taken up in the liquid volume.
In FIG. 4 a parallel arrangement of two microfluidic structures 1 a , 1 b of the invention is shown, wherein the two inlet channels 3 a , 3 b are supplied by a dividing channel 31 . In this case, a first liquid volume 41 can be combined each time with two different liquid volumes. In a microfluidic system with such a structure, the two combined liquid volumes can then be processed separately from each other.
In FIGS. 5 a to 5 d , the microfluidic structure 1 of the invention is shown in cross section at the height of the fluid chamber 2 with feed opening 5 . The microfluidic structure 1 is formed by a base plate 10 with depressions made therein and a cover foil 11 .
In FIG. 5 a , the feed opening 5 is fashioned in the base plate 10 underneath the fluid chamber 2 . In the region of the feed opening 5 , the base plate 10 has a recess 51 coming from underneath. In the region of the recess 51 , a septum 52 is arranged, so that after adding the second liquid volume with a syringe, an automatic closing seal of the feed opening 5 is achieved by the septum 52 , being also resistant to rather large pressures in the fluid chamber 2 .
In FIG. 5 b a feed opening 5 is shown in the base plate 10 , which is opened and closed again by a movable sealing element 53 . The sealing element 53 is driven by an actuator in the operator device.
In FIG. 5 c the feed opening 5 is formed by an opening 54 in the cover foil 11 . The opening 54 in this case can also be formed only by a syringe tip when placing the second liquid volume 42 in the fluid chamber 2 . When elastic foils are used as the cover foil 1 , a self closure of the opening 54 occurs once more after the puncture. In the base plate 10 , holding structures 7 in the form of several short steles 71 are arranged in the region of the holding position 6 for the second liquid volume 42 .
Also in FIG. 5 d the feed opening 5 is formed by an opening 54 in the cover foil 11 . In the base plate 10 there is arranged a holding structure 7 in the form of a recess 72 in the region of the holding position 6 for the second liquid volume 42 .
In FIG. 6 , in the region of the feed opening 5 for the second liquid volume 42 in the fluid chamber 2 , two steles 73 extending from the base plate 10 to the cover foil 11 are configured as holding structures 7 in the region of the holding position 6 . In this case, a second liquid volume 42 applied via the feed opening 5 is held between the side wall 21 , bottom 22 and top 23 surfaces of the fluid chamber 2 and the surfaces of the steles 73 . Alternatively to this, other surface structures which heighten the contact area between the second liquid volume 42 and the fluid chamber 2 can also be placed in the region of the holding position 6 for the second liquid volume 42 .
In FIG. 7 , a microfluidic structure 1 according to the invention is shown in the region of a dead-end channel 32 of a lab-on-a-chip. In operation, a first liquid volume 41 is propelled by a pressure difference in a main channel 33 . As soon as the first liquid volume 41 has arrived in the region of the intersection 34 of the main 33 and the dead-end channel 32 , a pressure is built up in the main channel 33 in the flow direction in front of the first liquid volume 41 , without diminishing the pressure acting in the flow direction behind the first liquid volume 41 . Since a compressible fluid such as a gas or air is enclosed at the dead end of the blind channel 32 in a large-volume reservoir 35 , the first liquid volume 41 advances into the dead-end channel 32 and is driven further in the dead-end channel 32 from the microfluidic structure 1 of the invention by further coordinated raising of the two pressures in the main channel 33 , whereupon a second liquid volume 42 kept on hand in a fluid chamber 2 in the dead-end channel 32 is combined with the first liquid volume 41 . By subsequent lowering of the pressures in the main channel 33 , the combined liquid volumes 41 + 42 is again driven out from the dead-end channel 32 into the main channel 33 and further onward.
In FIG. 8 is shown a sample embodiment of the microfluidic structure 1 of the invention with a structure supporting the combining of the liquid volumes. The fluid chamber 2 in this case has an indentation 24 of the side wall surface 21 of the fluid chamber 2 protruding into the asymmetrically shaped fluid chamber 2 in the region of the emptying of the inlet channel 3 into the fluid chamber 2 . Thanks to this structure 24 , the first liquid volume 41 advancing into the fluid chamber 2 is forced in the direction of the side wall surface 21 lying opposite the indentation 24 , so that a broadening of the first liquid volume 41 over the entire cross section of the fluid chamber is encouraged by wetting of all side surfaces 21 of the fluid chamber.
FIG. 9 shows a lab-on-a-chip 100 to carry out a PCR reaction, in top view, containing among other things the microfluidic structure of the invention 101 , 102 , 161 , 171 in multiple arrangement and different configurations.
During the operation of the lab-on-a-chip 100 , a lysed sample is added to the chip 100 by an opening 110 in the lab-on-a-chip 100 by syringe pump (not shown) and combined in a first microfluidic structure 101 of the invention with a liquid mixture 141 stored in the fluid chamber 105 , containing reagents for a reverse transcription/prePCR. In a meandering microfluidic channel 151 arranged thereafter in the flow direction, complete mixing of the sample with the liquid mixture 141 occurs. The resulting mixture is then delivered into the PCR chamber 153 by a fluidic connection that is opened up by a turning valve 152 (circular broken line).
The correct positioning of the mixture precisely in the PCR chamber is monitored by light barriers 154 , 157 , which depending on the level of filling of the channels at the end of the PCR chamber 153 let through a light signal directly onto a detector (not shown) or totally reflect the light signal. The further delivery of the sample by syringe pump stops once a signal change is detected at the light barrier 154 , thereby confirming the complete filling of the PCR chamber 153 . Next, the PCR chamber 153 is fluidically isolated from the other channels in the chip 100 by the turning valve 152 and the pre-amplification reaction occurs under cyclically occurring temperature regimes. The heating is done by heating clips placed in the operator device, which are placed against the PCR chamber 153 during operation. After this, a fluidic connection between the PCR chamber 153 and another channel 155 on the chip with an additional meandering microfluidic channel 156 for the mixing as well as an additional microfluidic structure 102 of the invention for the combining of two liquid volumes is opened up by the turning valve 152 . This microfluidic structure 102 of the invention for the combining of two liquid volumes has at the outlet channel 104 an exit opening 111 to the outside, closed with a hydrophobic or nonwettable membrane. At this opening 111 , a partial vacuum can be applied by an operator device (not part of the figure), enabling a pressure-driven delivery of the amplified sample solution into this structure 102 . As soon as a liquid is present at the gas-permeable and liquid-impervious membrane in the opening 111 , the delivery is halted by a measured pressure rise. An oligonucleotide mixture 142 previously stored in this microfluidic structure 102 of the invention via a feed opening is combined with the amplified sample solution. In a further process step, an excess pressure is applied via an operator device at a second opening 112 to the outside situated on the inlet channel 103 , being likewise closed by a hydrophobic or nonwettable semipermeable membrane. The entire solution present in the microfluidic structure 102 is in this way separated from an excess outside the microfluidic structure 102 . The excess is taken by the excess pressure and a corresponding switching of the turning valve 152 through a channel 158 to a waste channel on the lab-on-a-chip (not shown here). The liquid sample still present and now measured out in the structure 102 is delivered by an excess pressure applied at the opening 111 on the outlet channel 104 and a corresponding switching of the turning valve 152 once again into the PCR chamber 153 . In this instance as well, the correct filling of the PCR chamber 153 is recognized and controlled by a light barrier 157 . After repeated cyclical temperature runs in the PCR chamber 153 , the amplified sample solution is combined with the requisite dilution buffer solutions 162 , 172 via two additional microfluidic structures 161 , 171 of the invention for the combining of two liquid volumes and taken onward through an outlet opening 180 from the lab-on-a-chip 100 into a detection device (not shown).
Due to the rather large liquid volumes being combined in the first structure 161 , the first microfluidic structure 161 in the flow direction has holding structures 163 in the region of the holding position 164 for the first dilution buffer stored in the fluid chamber 167 . The holding structures 163 in this case are formed by small indentations 165 , 166 in the fluid chamber 167 at the start of the holding position 164 . Furthermore, this first microfluidic structure 161 has a narrowing of the cross section at one end 168 where the inlet channel 169 passes into the fluid chamber 168 , which supports an expansion of the sample solution as it is delivered into the fluid chamber 168 .
The fluid chambers 107 , 105 , 167 , 177 in this lab-on-a-chip 100 are asymmetrically shaped in the flow direction, while the feed openings 106 , 108 , 166 , 176 and holding positions 164 are arranged in the region of the one-ended indentation of the fluid chambers 107 , 105 , 167 , 177 , away from the central streamline from the inlet 169 , 103 to the outlet 104 channel through the fluid chamber 107 , 105 , 167 , 177 .
The channels contained in the lab-on-a-chip 100 can be joined together in various ways, for example, by a turning valve, as described in the German application DE 102008002674.3, so that various flow paths can be produced by switching. The openings of the channels being joined are sealed off from a chip surface by a valve body (not shown, the bearing surface is indicated by circular broken line). The valve body has recesses which are suitable for joining together various of the openings of the channels of the lab-on-a-chip.
LIST OF REFERENCE NUMBERS
1 , 1 ′ 1 a , 1 b , 101 , 102 , 161 , 171 microfluidic structure
2 , 2 ′, 2 a , 2 b , 105 , 167 , 177 , 107 fluid chamber
3 , 3 ′, 3 a , 3 b , 103 , 169 inlet channel
4 , 4 ′, 4 a , 4 b , 104 outlet channel
5 , 5 ′, 5 a , 5 b , 106 , 108 , 176 , 166 feed opening
6 , 164 holding position
7 , 163 holding structures
10 base plate
11 cover foil
21 side wall surface
22 bottom surface
23 top surface
24 , 165 , 168 indentation
25 largest cross sectional area of the fluid chamber
31 , 155 , 158 channel
32 dead-end channel
33 main channel
34 intersection
35 reservoir
41 first liquid volume
42 , 42 a , 42 b second liquid volume
43 third liquid volume
51 recess
52 septum
53 movable sealing element
54 opening
71 short steles
72 depression
73 steles
100 Lab-on-a-chip or microfluidic system
110 , 111 , 112 opening
121 excess
141 liquid mixture reverse transcription/pre-PCR
151 , 156 meandering microfluidic channel
152 turning valve
153 PCR chamber
154 , 157 light barrier
162 , 172 dilution buffer solutions
168 cross section narrowing
180 outlet opening
B largest width of cross section of fluid chamber in flow direction | Pressure-operable microfluidic structure for the bubble-free combining of two liquid volumes with a fluid chamber that has a feed opening, as well as an inlet and outlet channel emerging into the fluid chamber, wherein the fluid chamber has a cross section that broadens out relative to the inlet channel in the direction of flow from the inlet to the outlet channel and is designed, thanks to the broadened cross section, to broaden a first liquid volume that is essentially pressure-driven and conducted through the inlet channel and through the fluid chamber to a cross section at least approximately corresponding to the full cross section of the fluid chamber, while the fluid chamber has a holding position and is configured so that a second liquid volume, placed in the fluid chamber through the feed opening, can be held in the region of the holding position and the second liquid volume when the first liquid volume is moved through by pressure can be taken up by the latter and delivered as a combined liquid volume through the fluid chamber and into the outlet channel. | 1 |
TECHNICAL FIELD
The present invention relates generally to the implementation of protocols, such as cache coherence protocols.
DESCRIPTION OF RELATED ART
A protocol specifies the set of actions to be taken by a system component in response to events in all possible states. Protocol implementations can be hardwired, or they can be implemented in software using fully programmable processors or using programmable tables. Each implementation has drawbacks. Hardwired implementations increase development time and cannot be modified after tapeout. Software or fully programmable implementations are inefficient. Table-based programmable implementations typically require large table sizes for flexibility.
The latter implementation uses a concatenation of event encoding and state encoding as an index into the table specifying the protocol. If x bits are used for encoding events and y bits are used for encoding states, then up to 2 x distinct events can be encoded, and up to 2 y can be defined. The table size is 2 x+y entries. The table is loadable to allow protocol flexibility for improving performance as well as for correcting protocol errors. However, the more flexibility that is allowed means the more the table size grows. In order to keep the size of the table practical, states need to be packed carefully using as few bits as possible. This reduces the flexibility of the protocol significantly. For example, suppose 5 bits were assigned for a certain state component, and a protocol problem was discovered for which the best solution required 33 distinct values for that state component, then that solution is not feasible. If more bits were dedicated beforehand, that table size increases exponentially and can require multi-cycle access time.
SUMMARY OF THE INVENTION
For most protocols, the number of distinct cases is typically much less than 2 x+y , where x and y are the binary logarithms of the number of events and states, respectively. The size of the protocol table can be reduced by adding a key field to each entry in the protocol table. A larger key field provided greater flexibility. By using a one-cycle associative search in the table, the number of entries in the table can be independent of the key size. This allows more bits to be used in the key components, and more bits can be dedicated to components that are completely defined by the protocol, such as inter-node requests and responses and transient states. In addition, state bits need not be packed tightly, thus increasing flexibility.
A protocol table in accordance with the invention includes key fields and action fields. Whenever a protocol event, such as an incoming command, requires protocol action, a key can be formed as follows. An event identifying component can be extracted, for example from an incoming message. Bits that identify the current state can be extracted from, for example, a pending buffer or a memory directory. A key is then formed to be used for associative lookup in the protocol table. The output of the lookup is a set of action fields in the table entry with a matching key field. If a match is not found between the formed key and a matching key field in the table, then there is a protocol error.
In accordance with the invention, there is provided a method for accessing a table comprising the steps of providing a content addressable table comprising a plurality of entries, wherein each entry includes a key field and an output field, constructing a key value from an input, searching the table for an entry whose key field matches the key value constructed from the input, and returning the output field of an entry whose key field matches that of the key value.
In a further aspect of the invention, the step of searching of the table comprises an associative search.
In a further aspect of the invention, the method includes generating an error if no entry on the table has a key field that matches the key value.
In a further aspect of the invention, the table further includes a mask field, and the step of searching the table further comprises seeking the entry whose key field matches a bitwise AND of its mask field with the key value.
In a further aspect of the invention, the table is a protocol table, and the output field of the protocol table is indicative of an action to be taken.
In a further aspect of the invention, the input includes a command and a state machine state indicator, wherein the key value is determined from the command and state indicator.
In another aspect of the invention, there is provided a program storage device readable by a computer, tangibly embodying a program of instructions executable by the computer to perform the method steps for accessing a protocol table.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an example of a system environment incorporating the current invention.
FIG. 2 shows an example implementation of a conventional protocol table.
FIG. 3 shows the lookup method implementation of a conventional protocol table.
FIG. 4 shows one embodiment using content addressable memory and key fields included in protocol table entries.
FIG. 5 shows the method for lookup in an embodiment using content addressable memory and key fields included in protocol table entries.
FIG. 6 shows an embodiment using content addressable memory, with key and mask fields included in protocol table entries.
FIG. 7 shows a lookup method in an embodiment using content addressable memory, with key and mask fields included in protocol table entries.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
It is to be understood that the present invention may be implemented in various forms of hardware, software, firmware, special purpose processors, or a combination thereof. Preferably, the present invention is implemented as a combination of both hardware and software, the software being an application program tangibly embodied on a program storage device. The application program may be uploaded to, and executed by, a machine comprising any suitable architecture. Preferably, the machine is implemented on a computer platform having hardware such as one or more central processing units (CPU), a random access memory (RAM), and input/output (I/O) interface(s). The computer platform also includes an operating system and microinstruction code. The various processes and functions described herein may either be part of the microinstruction code or part of the application program (or a combination thereof), which is executed via the operating system. In addition, various other peripheral devices may be connected to the computer platform such as an additional data storage device.
It is to be further understood that, because some of the constituent system components depicted in the accompanying Figures may be implemented in software, the actual connections between the system components may differ depending upon the manner in which the present invention is programmed. Given the teachings herein, one of ordinary skill in the related art will be able to contemplate these and similar implementations or configurations of the present invention.
FIG. 1 depicts an exemplary system environment for implementing the methods and systems of the present invention. The system includes one or more computing devices 110 , each of which can comprise, inter alia, one or more processors ands caches 120 , a shared/remote cache 130 , a main memory 140 , and a coherence controller 150 that includes a protocol table 160 . The computer devices 110 are interconnected through a system area network 100 , which can be a local area network, or a global network, such as the Internet. Computing device 110 can additionally include an I/O interface (not shown) which couples to a display (not shown) and various input devices such as a mouse and a keyboard (not shown). The support circuits can include circuits such as cache, power supplies, clock circuits, and a communication bus. The memory 140 can include random access memory (RAM), read only memory (ROM), disk drive, tape drive, etc., or a combinations thereof.
The computing device 110 also includes an operating system and microinstruction code. The various processes and functions described herein can either be part of the microinstruction code or part of the application program (or combination thereof), which is executed via the operating system. In addition, various other peripheral devices can be connected to the computer platform such as an additional data storage device and a printing device. The system depicted here is exemplary, and the invention is applicable to any finite state machine (or protocol) where the number of possible inputs (states, operations, etc) is large. One such usage in current systems is that of cache coherence protocols for large scale shared memory multiprocessor systems, however, the invention can be implemented in any computing or network system that utilizes a protocol.
FIG. 2 depicts an implementation of a conventional protocol table. Protocol table 200 includes 2 s entries 220 , which can be indexed by numbers in the range 0 . . . 2 s -1. Each protocol table entry 220 includes a protocol output 230 , which specifies an action result 240 of a protocol table lookup. The protocol table 200 can be accessed by a protocol input 210 , which includes a key comprising S bits. More precisely, if the range of possible key values is from 0 to M-1 then the table size is M entries. Note that the number of key values (say K) actually used can be much less than M.
FIG. 3 depicts a lookup method 300 for the table depicted in FIG. 2 . A key value k is constructed at step 310 from the protocol inputs. These inputs include commands and an indicator of the current state. Commands can include requests/responses from local or remote nodes, memory directory or remote cache evictions, or internal commands. The internal state refers to the state of a state machine that is utilizing the protocol table, and includes the state of the command source node, a stable state such as a memory directory or remote cache directory access, a transient state as in the case of a pending buffer, address or resource conflicts, the status of data, or whether the command is for a last expected response. Once the key k is constructed, it is used to read 320 the corresponding protocol table entry. The protocol output is returned from the table at step 330 . A protocol table output is indicative of an action to be taken, and can include sending an outgoing message to a requester or home nodes an action on a pending buffer, updating a stable state, updating a transient state bit vector, transitioning to a new transient state, returning the status of data, performing an action on a remote cache, such as a read or write, etc.
FIG. 4 depicts an implementation of one embodiment of a protocol table in accordance with the invention. Protocol table 400 is content addressable, and includes a plurality of table entries 420 . Each protocol table entry 420 further includes a key field 430 and an output field 440 , which will be the result 450 of a table lookup. The protocol input 410 includes a key of size S bits. If the number of possible key values is K, then the table size is K entries, or slightly more to accommodate possible changes. The table should be designed so that each key field is unique, so that there is exactly one output field for each possible key field.
FIG. 5 depicts a lookup method 500 for the table depicted in FIG. 4 , in accordance with the invention. A key value k is constructed from the protocol inputs at step 510 . As in the conventional case, the inputs include a command and an indicator of the current state. Methods of forming a key value from a command indicator and a state indicator are known in the art. The table 400 is searched associatively at step 520 for an entry with key=k. If, at step 530 , exactly one matching entry was found, then the corresponding output portion 440 of the protocol table entry is returned at step 540 as the result of the table lookup operation. However, if no matching entry is found in the table, a protocol error is generated at step 550 . This error can be in the form of an exception. Similarly, a table with more than one action for a given set of inputs is an error condition.
FIG. 6 depicts an implementation of another embodiment of a protocol table in accordance with the invention. Protocol table 600 is content addressable, and includes a plurality of table entries 620 . Each protocol table entry 620 further includes a key field 630 , a mask field 640 , and an output field 650 , which is produced as the result 660 of a protocol table lookup operation. The protocol input 610 includes a key k of S bits. The inclusion of a mask field in the protocol table entry can allow a smaller table size for a larger number of key values. The mask can cover all or part of the key field. A mask bit is clear (i.e., zero) if the corresponding key bit is immaterial to choosing the entry. In this embodiment, the key field is compared to a function of the mask field and the input key value. The table should be designed so that each key field is unique, so that there is there is exactly one output field for each possible combination of input key value and mask field.
FIG. 7 depicts a lookup method 700 for the table depicted in FIG. 6 , in accordance with the invention. A key value k is constructed from the protocol inputs at step 710 , as before. At step 720 , the table is associatively searched for the entry with key=f(k, mask), where f is a function of the key value and the mask field. In one embodiment, this function can be a bitwise AND of the mask and key value. Alternatively, a bitwise OR function can also be used by flipping all of the bits. These functions are exemplary, and other functions of the mask and key value are within the scope of the invention. If, at step 730 , exactly one matching entry was found, then the output portion 650 of the protocol table entry is returned at step 740 as the result of the table lookup operation. Thus, the entry chosen to provide the output of the protocol table lookup is the entry with a function of its mask field equal and the input key equal to its key field. However, if no matching entry is found in the table, a protocol error or exception is generated at step 750 . Similarly, a table with more than one action for a given set of inputs and mask is an error condition.
It is to be further understood that, because some of the constituent system components and method steps depicted in the accompanying figures can be implemented in software, the actual connections between the systems components (or the process steps) may differ depending upon the manner in which the present invention is programmed. Given the teachings of the present invention provided herein, one of ordinary skill in the related art will be able to contemplate these and similar implementations or configurations of the present invention.
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. Accordingly, the protection sought herein is as set forth in the claims below. | A method for accessing a protocol table includes providing a content addressable protocol table comprising a plurality of entries, wherein each entry includes a key field and an output field, constructing a key value from a protocol input, associatively searching the table for an entry whose key field matches the key value constructed from the input, and returning the output field of an entry whose key field matches that of the key value. The table optionally includes a mask field, and searching the table includes seeking the entry whose key field matches a bitwise AND of its mask field with the key value. An error is generated if no matching entry is found on the table. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is the U.S. national phase of PCT/DE2007/002260 filed Dec. 13, 2007. PCT/DE2007/002260 claims the benefit under the Convention of German Patent Application No. 10 2006 060 141.6 filed Dec. 18, 2006.
FIELD OF THE INVENTION
[0002] The invention relates to a headlight lens for a vehicle headlight, in particular for a motor vehicle headlight, as well as to a vehicle headlight.
BACKGROUND INFORMATION
[0003] A headlight lens of that type is e.g. known from U.S. Pat. No. 3,708,221, WO 02/31543 A1, WO 03/074251 A1 and DE 100 52 653 A1. Further types of vehicle headlights are known e.g. DE 101 18 687 A1 and DE 198 29 586 A1.
[0004] DE 203 20 546 U1 discloses a lens blank-moulded on both sides and having a curved surface, a planar surface and a retention edge integrally moulded on the lens edge, wherein a supporting edge of a thickness of at least 0.2 mm and projecting with respect to the planar surface is integrally formed on the retention edge. Herein, the supporting edge is integrally formed on the outer circumference of the headlight lens. A further headlight lens having a supporting edge is disclosed e.g. by DE 10 2004 048 500 A1.
[0005] DE 20 2004 005 936 U1 discloses a lens for illuminating purposes, in particular a lens for a headlight for mapping or imaging light emitted from a light source and reflected by a reflector for generating a predetermined illumination pattern, said lens having two surfaces opposing each other, wherein areas of different optical dispersion effects are provided on at least a first surface.
[0006] EP 0 969 246 A2 discloses an over-dimensioned lens, wherein the lens grinding and the corresponding projection plane and projection parameter of the reflector mirror are dimensioned such with respect to the lens that only an interior partial area of the lens is used directly. The over-dimensioned edge area merely serves for an optical magnification of the headlight design.
[0007] With respect to their optical properties or their photometric standards, headlight lenses are subject to narrow criteria of design. This particularly applies to a light and dark borderline 75 , as has been represented, by way of example, in a diagram 70 and a photo 71 in FIG. 9 . Herein, the gradient G of the light and dark borderline 75 and the glare value HV of the vehicle headlight into which the headlight lens is installed are important photometric standard values.
[0008] It is the object of the invention to reduce the costs in manufacturing a headlight lens for a vehicle headlight, in particular for a motor vehicle headlight, without exceeding photometric standard values.
SUMMARY
[0009] The aforementioned problem is solved by a method for manufacturing a batch comprising at least five hundred or at least sixteen headlight lenses for a vehicle headlight or a motor vehicle headlight, wherein each headlight lens comprises a lens body made from transparent material and having an essentially planar, optically operative surface as well as a convexly curved, optically operative surface, the method comprising pressing a pre-form between a first mould for pressing the convexly curved, optically operative surface and a second mould for pressing the essentially planar, optically operative surface, which second mould comprises a first mould section and an annular second mould section enclosing the first mould section, wherein due to the pressing a headlight lens of the batch is formed, the headlight lens having an integrally formed lens edge, wherein, by means of an offset depending on the volume of the pre-form a step is pressed into the headlight lens between the second mould section and the first mould section, and wherein the first mould section is set back with respect to the second mould section at least in the region of the offset such that the height of a step of a headlight lens of the batch differs by more than 0.05 mm from the height of a step of a further headlight lens of the batch.
[0010] In particular, it is provided that the essentially planar, optically operative surface is an optically operative surface to be made facing a light source. In particular, it is provided that the convexly curved, optically operative surface is an optically operative surface to be made facing away from a light source. In an embodiment, the convexly curved, optically operative surface is aspheric.
[0011] In the sense of the invention, the transparent material is in particular glass. In the sense of the invention, the term blank-moulding is to mean, in particular, that an optically operative surface is to be pressed such that a subsequent finishing step of the contour of this optically operative surface may be dispensed with or is omitted or is not provided. An integrally formed lens edge, when taken in the sense of the invention, is in particular not to comprise an optically operative surface.
[0012] In an embodiment of the invention, the step extends essentially parallel to the optical axis of the headlight lens. In another embodiment, the step is (if necessary additionally) inclined with respect to the optical axis of the headlight lens in the direction of the optical axis.
[0013] In a yet further embodiment of the invention, the distance between the first mould section and the first mould is dependent on the volume of the pre-form. In a further embodiment of the invention, the distance between the second mould section and the first mould is independent of the volume of the pre-form. In a yet further preferred embodiment of the invention, the second mould section contacts the first mould. In a still further embodiment of the invention, a contact shoulder is pressed into the lens edge by means of the first mould, wherein the contact shoulder expediently extends essentially orthogonally with respect to the optical axis of the headlight lens.
[0014] In a yet further embodiment of the invention, the essentially planar, optically operative surface projects by no more than 1 mm, advantageously by not more than 0.5 mm beyond the lens edge or a part of the lens edge when seen in the direction of the optical axis of the headlight lens. This in particular means that the height of a step amounts to no more than 1 mm, advantageously no more than 0.5 mm.
[0015] In a further expedient embodiment of the invention, the thickness of the lens edge amounts to at least 2 mm. In a yet further embodiment of the invention, the thickness of the lens edge amounts to no more than 5 mm.
[0016] In a still further embodiment of the invention, the diameter of the headlight lens amounts to at least 40 mm. In a yet further embodiment of the invention, the diameter of the headlight lens amounts to no more than 100 mm.
[0017] In still another embodiment of the invention, the diameter of the essentially planar, optically operative surface amounts to no more than 110% of the diameter of the convexly curved, optically operative surface. In a still further expedient embodiment of the invention, the diameter of the essentially planar, optically operative surface amounts to at least 90% of the diameter of the convexly curved, optically operative surface.
[0018] In an embodiment of the invention, the essentially planar, optically operative surface and/or the convexly curved, optically operative surface is round, in particular circular, or essentially circular.
[0019] In a further embodiment of the invention, the surface of the lens edge or essentially a predominant or at least a predominant or essential portion of the surface of the lens edge extends essentially parallel to the optical axis of the headlight lens along the outer circumference of the lens edge. In this sense, essentially parallel to the optical axis is to mean or is to comprise in particular an inclination of 0° up to 8°, in particular 0° to 5°, with respect to the optical axis.
[0020] In an embodiment, the essentially planar, optically operative surface and/or the convexly curved, optically operative surface has a roughness of less than 0.1 μm, in particular less than 0.08 μm, at least in more than one half thereof or essentially in its totality. Roughness in the sense of the invention is in particular to be defined as Ra, in particular according to ISO 4287.
[0021] The above-mentioned problem is moreover solved by a method for producing a batch of, in particular, at least sixteen or at least fifty-three headlight lenses for a vehicle headlight, wherein the headlight lenses of the batch are blank-moulded according to the aforementioned process. In an embodiment of the invention, the batch comprises at least five hundred headlight lenses. In a further embodiment of the invention, the headlight lenses are placed in a transport container for transporting the headlight lenses. In yet a further expedient embodiment of the invention, the height of a step of a headlight lens of the batch differs by more than 0.05 mm, advantageously by more than 0.1 mm, from the height of a step of a further headlight lens of the batch. In an embodiment of the invention, the step extends essentially parallel to the optical axis of the headlight lens. In a further embodiment, the step is, if necessary additionally, inclined with respect to the optical axis of the headlight lens when seen in the direction of the optical axis.
[0022] The above-mentioned problem is moreover solved by a batch of, in particular, at least sixteen or at least fifty-three blank-moulded headlight lenses for vehicle headlights having an integrally moulded lens edge, wherein each one of the headlight lenses of the batch comprises a lens body, each, made of transparent material with an essentially planar, optically operative surface, each, and a convexly curved, optically operative surface, each, wherein the essentially planar, optically operative surfaces project, in the form of a step and when seen in the direction of each optical axis of a headlight lens, beyond the respective lens edge or part of the respective lens edge, and wherein the height of a step of a headlight lens of the batch differs by more than 0.05 mm, advantageously by more than 0.1 mm, from the height of a step of a further headlight lens of the batch. In an embodiment of the invention, the step extends essentially parallel to the optical axis of the headlight lens. In another embodiment, the step is, if necessary in addition, inclined with respect to the optical axis of the headlight lens when seen in the direction of the optical axis.
[0023] In an expedient embodiment of the invention, the batch comprises at least five hundred headlight lenses. In a further embodiment of the invention, the headlight lenses of the batch have a contact shoulder, each, on the lens edge situated on the side of the respective headlight lenses facing away from the step, wherein the contact shoulder advantageously extends essentially orthogonally with respect to the optical axis of the headlight lens.
[0024] In a further expedient embodiment of the invention, the essentially planar, optically operative surface projects, when seen in the direction of the optical axis of the headlight lens, beyond the lens edge or part of the lens edge by no more than 1 mm, advantageously by no more than 0.5 mm. This, in particular, means that the height of a step is no more than 1 mm, advantageously no more than 0.5 mm.
[0025] In yet a further expedient embodiment of the invention, the thickness of the lens edge is at least 2 mm. In a yet further embodiment of the invention, the thickness of the lens edge is no more than 5 mm.
[0026] In a yet further embodiment of the invention, the diameter of the headlight lens amounts to at least 40 mm. In a further embodiment of the invention, the diameter of the headlight lens amounts to no more than 100 mm.
[0027] In a still further expedient embodiment of the invention, the diameter of the essentially planar, optically operative surface amounts to no more than 110% of the diameter of the convexly curved, optically operative surface. In a yet further expedient embodiment of the invention, the diameter of the essentially planar, optically operative surface amounts to at least 90% of the diameter of the convexly curved, optically operative surface.
[0028] In an embodiment of the invention, the essentially planar, optically operative surface and/or the convexly curved, optically operative surface is round, in particular circular or essentially circular.
[0029] In a yet further expedient embodiment of the invention, the surface of the lens edge or at least a predominant or essential part of the surface of the lens edge extends along the outer circumference of the lens edge essentially parallel to the optical axis of the headlight lens. In the sense thereof, “essentially parallel to the optical axis” is to mean or comprise, in particular, an inclination with respect to the optical axis of 0° to 8°, in particular 0° to 5°.
[0030] The essentially planar, optically operative surface and/or the convexly curved, optically operative surface in an embodiment has, in more than half thereof or essentially in its totality, a roughness of less than 0.1 μm, in particular of less than 0.08 μm. Roughness, in the sense of the invention, is to be defined, in particular, as Ra, particularly according to ISO 4287.
[0031] The aforementioned is moreover solved by a transport container for transporting headlight lenses, wherein a plurality of headlight lenses for vehicle headlights, in particular for motor vehicle headlights, is arranged in the transport container, wherein each one of the headlight lenses of said plurality of headlight lenses comprises a blank-moulded lens body made of transparent material with an essentially planar, optically operative surface, each, and with an convexly curved, optically operative surface, each, and wherein each of the headlight lenses of the plurality of headlight lenses externally comprises a lens edge, each, on their convexly curved, optically operative surfaces, wherein the essentially planar, optically operative surfaces, when seen in the direction of the respective optical axis of a headlight lens, project, in the form of a step, beyond the respective lens edge or a part of the respective lens edge, and wherein the height of a step of a headlight lens of said plurality of headlight lenses differs by more than 0.05 mm, preferably by more than 0.1 mm, from the height of a step of a further headlight lens of said plurality of headlight lenses. In an embodiment of the invention, the step extends essentially parallel to the optical axis of the headlight lens. In another embodiment, the step is, if necessary additionally, inclined with respect to the optical axis of the headlight lens when seen in the direction of the optical axis.
[0032] The aforementioned problem is moreover solved by a headlight lens for a vehicle headlight, in particular for a motor vehicle headlight, wherein the headlight lens comprises a blank-moulded lens body made from transparent material and having an essentially planar, optically operative surface and a convexly curved, optically operative surface, and wherein the headlight lens, on the convexly curved, optically operative surface, externally comprises a lens edge, wherein the essentially planar, optically operative surface, when seen in the direction of an optical axis of the headlight lens, projects beyond the lens edge or a part of the lens edge in a stepped manner, and wherein the headlight lens has a contact shoulder on the lens edge on the side of the headlight lens facing away from the step, wherein the contact shoulder advantageously extends essentially orthogonally with respect to the optical axis of the headlight lens, and wherein the essentially planar, optically operative surface advantageously has a roughness of less than 0.1 μm, in particular of less than 0.8 μm. Roughness, in the sense of the invention, is particularly to be defined as Ra, in particular according to ISO 4287.
[0033] In an embodiment of the invention, the step extends essentially parallel to the optical axis of the headlight lens. In another embodiment, the step is, if necessary in addition, inclined with respect to the optical axis of the headlight lens when seen in the direction of the optical axis.
[0034] In a yet further expedient embodiment of the invention, the essentially planar, optically operative surface projects beyond the lens edge or a part of the lens edge, when seen in the direction of the optical axis, by not more than 1 mm, expediently by not more than 0.5 mm. This, in particular, means that the height of a step amounts to no more than 1 mm, advantageously to no more than 0.5 mm.
[0035] In a further expedient embodiment of the invention, the thickness of the lens edge amounts to at least 2 mm. In a further expedient embodiment of the invention, the thickness of the lens edge amounts to no more than 5 mm.
[0036] In yet a further embodiment of the invention, the diameter of the headlight lens amounts to at least 40 mm. In still a further embodiment of the invention, the diameter of the headlight lens amounts to no more than 100 mm.
[0037] In a further embodiment of the invention, the diameter of the essentially planar, optically operative surface amounts to no more than 110% of the diameter of the convexly curved, optically operative surface. In a yet further embodiment of the invention, the diameter of the essentially planar, optically operative surface amounts to at least 90% of the diameter of the convexly curved, optically operative surface.
[0038] In an embodiment of the invention, the essentially planar, optically operative surface and/or the convexly curved, optically operative surface is round, in particular circular or essentially circular.
[0039] In an embodiment, the convexly curved, optically operative surface has, for more than half of it or taken essentially in its totality, a roughness of less than 0.1 μm, in particular of less than 0.8 μm. Roughness, in the sense of the invention, is particularly to be defined as Ra, in particular according to ISO 4287.
[0040] The aforementioned problem is furthermore solved by a vehicle headlight, in particular a motor vehicle headlight, having a light source, a shield and a headlight lens in particular comprising one or several of the above-mentioned features, for imaging an edge of the shield as a light and dark borderline, wherein the headlight lens comprises a blank-moulded lens body made from transparent material and having a particularly essentially planar, optically operative surface facing the light source and a particularly convexly curved, optically operative surface facing away from the light source, and wherein the headlight lens, on the optically operative surface facing away from the light source, externally comprises a lens edge, wherein the optically operative surface facing the light source projects beyond the lens edge or a part of the lens edge when seen in the direction of an optical axis of the headlight lens and/or in the direction of the light source, wherein a step is provided between the optically operative surface facing the light source and a surface of the lens edge facing the light source, wherein the headlight lens has a contact shoulder advantageously on the lens edge on the side of the headlight lens facing away from the step, and wherein the essentially planar, optically operative surface advantageously has a roughness of less than 0.1 μm, in particular of less than 0.08 μm.
[0041] Roughness, in the sense of the invention, is particularly to be defined as Ra, in particular according to ISO 4287. In an embodiment of the invention, the step extends essentially parallel to the optical axis of the headlight lens. In another embodiment, the step is, if necessary additionally, inclined with respect to the optical axis of the headlight lens when seen in the direction of the optical axis.
[0042] In an expedient embodiment of the invention, the vehicle headlight is (at least as well) formed as a non-dazzling headlight. In yet a further embodiment of the invention, the gradient of the light and dark borderline is no more than 0.5. In a yet further embodiment of the invention, the glare value of the vehicle headlight is no more than 1.5 Lux.
[0043] The above-mentioned problem is moreover solved by a vehicle having an aforementioned vehicle headlight, wherein the light and dark borderline may, in an embodiment of the invention, be imaged on a roadway on which the motor vehicle may be arranged.
[0044] The height of the aforementioned steps advantageously amounts to at least 0.1 mm.
[0045] It may be provided that an essentially planar, optically operative surface comprises a (concave) curvature having a radius of curvature in the order of 0.5 m.
[0046] Further advantages and details may be taken from the following specification of examples of embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] FIG. 1 shows a motor vehicle;
[0048] FIG. 2 shows a schematic representation of a vehicle headlight;
[0049] FIG. 3 shows a cross-section through an example of embodiment of a headlight lens for a vehicle headlight according to FIG. 2 ;
[0050] FIG. 4 shows a cut-out of the cross-section according to FIG. 3 ;
[0051] FIG. 5 shows; by way of a cut-out; a cross-section through a modified example of embodiment of a headlight lens for a vehicle headlight according to FIG. 2 ;
[0052] FIG. 6 shows a method for manufacturing a headlight lens according to FIG. 3 ;
[0053] FIG. 7 shows an apparatus for pressing a headlight lens according to FIG. 3 ;
[0054] FIG. 8 shows a transport container for transporting a plurality of headlight lenses; and
[0055] FIG. 9 shows the distribution of illumination of a headlight.
DETAILED DESCRIPTION
[0056] FIG. 1 shows a motor vehicle 100 having a vehicle headlight 1 schematically depicted in FIG. 2 and having a light source 10 for generating light, a reflector 12 for reflecting light to be generated by means of the light source 10 , and a shield 14 . The vehicle headlight 1 moreover comprises a one-piece headlight lens 2 blank-moulded on both sides, for changing the beam direction of light to be generated by means of the light source 10 , and in particular for imaging an edge of the shield 14 as a light and dark borderline 75 (also see FIG. 9 ), which edge has been designated by reference numeral 15 in FIG. 2 .
[0057] The headlight lens 2 comprises a lens body 3 made from transparent material, in particular glass, which body includes an essentially planar, optically effective and operative surface 5 facing the light source 10 , and a convexly curved, optically effective and operative surface 4 facing away from the light source 10 . The headlight lens 2 moreover comprises an integrally formed lens edge 6 , by means of which the headlight lens 2 may be attached inside the vehicle headlight 1 . The elements in FIG. 2 have been drafted in particular consideration of simplicity and clearness but not necessarily to scale. For example, the order of magnitude of some elements has been exaggerated with respect to other elements in order to improve comprehension of the example of embodiment of the present invention.
[0058] FIG. 3 shows a cross-section through an example of embodiment of the headlight lens 2 for the vehicle headlight 1 according to FIG. 2 . FIG. 4 shows a cut-out of the headlight lens 2 , said cut-out having been marked by a dashed-dotted circle. The essentially planar, optically effective surface 5 projects, in the shape of a cascade or step 60 , beyond the lens edge 6 or beyond the surface 61 of the lens edge 6 facing the light source 10 in the direction of the optical axis 20 of the headlight 2 , wherein the height h of the step 60 is no more than 1 mm, advantageously no more than 0.5 mm. The nominal value of the height h of the step 60 advantageously amounts to 0.2 mm. Moreover, the headlight lens 2 has a contact shoulder 65 on the lens edge 6 on that side of the headlight lens 2 which faces away form the step 60 .
[0059] The thickness r of the lens edge 6 amounts to at least 2 mm, however, to no more than 5 mm. The diameter DL of the headlight lens 2 amounts to at least 40 mm, however, to no more than 100 mm. The diameter DB of the essentially planar, optically effective surface 5 is equal to the diameter DA of the convexly curved, optically effective surface 4 . In an expedient embodiment, the diameter DB of the essentially planar, optically effective surface 5 amounts to no more than 110% of the diameter DA of the convexly curved, optically effective surface 4 . Furthermore, the diameter DB of the essentially planar, optically effective surface 5 advantageously amounts to at least 90% of the diameter DA of the convexly curved, optically effective surface 4 . Advantageously, the diameter DL of the headlight lens 2 is roughly 5 mm larger than the diameter DB of the essentially planar, optically effective surface 5 or than the diameter DA of the convexly curved optically, effective surface 4 .
[0060] FIG. 5 shows a headlight lens 2 A modified with respect to headlight lens 2 , wherein same reference numerals as having been used with respect to headlight lens 2 denominate same or similar objects. As a modification with regard to headlight lens 2 , headlight lens 2 A has an oblique step 60 A (e.g. inclined by 45°).
[0061] FIG. 6 shows a process for manufacturing the headlight lens 2 . Herein, the manufacture of a pre-form, such as e.g. of a gob, occurs in a step 30 . To this end, glass is melted in a melting device such as a trough. The melting device may comprise e.g. a controllable outlet. Liquid glass is passed from the melting device into a pre-form device. This pre-form device may include e.g. moulds into which a defined amount of glass is poured. It may also be provided that the pre-form device is designed as in injection press for pressing pre-forms which, if necessary, are close to their final contour. It has been provided that the volume of the pre-form may deviate by up to 3% from the nominal or index value of the pre-form.
[0062] A step 31 follows, in which step the pre-form is transferred to a tempering device by means of which the thermal gradient of the pre-form is reversed. Optionally, the pre-form is cooled in a step 36 and warmed up or heated in a step 37 after an indefinite period of time has lapsed.
[0063] A step 32 follows in which the pre-form is blank-moulded—by means of an apparatus for pressing a headlight lens as shown in FIG. 7 —between a first mould 40 and a second mould, the latter comprising a first mould section 41 and a second mould section 42 which is annular and encloses the first mould section 41 , to form a headlight lens 2 having an integrally moulded lens edge 6 , wherein the cascade or step 60 is pressed into the headlight lens 2 by means of an offset 43 depending on the volume of the pre-form, which pressing occurs between the first mould section 41 and the second mould section 42 . Herein, the pressing is, in particular, not performed in vacuum or under significant low-pressure. The pressing particularly occurs under air-pressure (atmospheric pressure). The first mould section 41 and the second mould section 42 are non-positively coupled together by means of springs 45 and 46 . Herein, the pressing is performed such that the distance between the first mould section 41 and the first mould 40 is dependent on the volume of the pre-form or of the headlight lens 2 pressed from it, and the distance between the second mould section 42 and the first mould 40 is independent of the volume of the pre-form or of the headlight lens 2 pressed from it.
[0064] After pressing, and in a step 33 , the headlight lens 2 is placed on a cooling track and cooled. An optional step 34 follows, in which the essentially planar surface 5 is polished. Subsequently, and in a step 35 , the headlight lens 2 is packaged into a transport container 50 represented in FIG. 8 for transporting headlight lenses together with further headlight lenses 201 , 202 , 203 of the batch, all designed corresponding to headlight lens 2 . In the transport container 50 , the height of a step of a headlight lens 201 differs by more than 0.05 mm, advantageously by more than 0.1 mm, from the height of a step of a further headlight lens 203 .
[0065] It has shown that the lens designed according to the invention is robust with regard to its optical properties such that the required optical properties as they have been explained e.g. referring to FIG. 9 may be matched even in the case of the aforementioned deviations of the volume of the pre-form. Thereby, the aforementioned deviations regarding the volume of the pre-form may be tolerated, and the costs for producing such a headlight lens may be reduced. | The invention relates to a headlight lens for a vehicle headlight, particularly for a motor vehicle headlight, wherein the headlight lens comprises a bright-molded lens body made of a transparent material, having a substantially plane optically effective surface and a convexly curved optically effective surface, wherein the headlight lens comprises a lens edge on the outside of the convexly curved optically effective surface, wherein the substantially plane optically effective surface, protrudes over the lends edge, or over part of the lens edge, in a stepped manner in the direction of an optical axis of the headlight lens. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of United Kingdom Patent Application No. 0328440.3, filed on Dec. 9, 2003, which hereby is incorporated by reference in its entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates to controlling a fluid well, such as a hydrocarbon extraction well.
BACKGROUND OF THE INVENTION
[0003] Subsea hydrocarbon extraction wells are controlled, typically, by hydraulically powered valves and fluid control chokes, downhole, with the control of the hydraulic power to such devices being effected by directional control valves (DCVs) which are electrically operated. The DCVs are typically housed in a control pod mounted on a well tree located on the sea bed above the well production tubing. The DCVs are, in turn, controlled by electronics, housed in a subsea electronics module (SEM) located in the control pod. The SEM is supplied with both electric power and control signals via an umbilical from a sea surface platform. Modern systems typically send the control signals by a communication system which superimposes them on the power feeds. The communication system is generally bi-directional in that not only are control signals to the fluid control devices required, but the outputs of sensors, such as pressure, temperature and flow sensors, are also required to be transmitted to the surface platform to provide the operator with well operation data. Well operators require high availability and reliability for both the power supply and the communication systems and in an effort to achieve this, the power feed, with its superimposed control and sensing signals, is duplicated within the umbilical, or even by a second umbilical, with further duplication of electronic modules in the control pod. Furthermore, future wells will use fluid control devices such as chokes which have dual redundant operating mechnisms that employ both an electrical and hydraulic drive, such that if one fails the other is still operable.
[0004] However, these techniques only provide a limited protection against failure, with the situation becoming much more serious when a plurality of fluid control chokes are fitted to a well, as is the trend in modern wells.
[0005] According to the present invention from one aspect, there is provided apparatus for controlling a fluid well comprising, a control device for location downhole and operable selectively by first and second drive means, there being first and second power supply means and first and second control channels for control signals for the first and second drive means, the arrangement being such that if one of the power supplies fails, the respective drive means is operable via the other power supply, the apparatus further comprising first and second means for routing control signals from the first and second channels respectively to the first and second drive means, the routing means being cross-connected so that, in the event of a fault, control signals from the second channel are routed via the first routing means to the second drive means and/or control signals from the first channel are routed via the second routing means to the first drive means.
SUMMARY OF THE INVENTION
[0006] According to the present invention from another aspect, there is provided apparatus for controlling a fluid production well, comprising:
a) a control device for location downhole; b) first drive means for operating the control device; c) second drive means for operating the control device, the control device being operable selectively by the first and second drive means; d) first power supply means; e) second power supply means; f) a first control channel, for control signals for the first drive means; g) a second control channel, for control signals for the second drive means; h) first switching means, for switching power and control signals to the first drive means; and i) second switching means, for switching power and control signals to the second drive means; wherein
i) the first and second power supply means and the first and second control channels are connected to the first switching means and also to the second switching means, the arrangement being such that, in normal operation, power from the first power supply means powers the first drive means via the first switching means and power from the second power supply means powers the second drive means via the second switching means, and in the event of a fault, power from the first power supply means powers the second drive means or power from the second power supply means powers the first drive means; and ii) the first switching means includes means for routing control signals from the first control channel to control the first drive means and the second switching means includes means for routing control signals from the second control channel to control the second drive means, the first and second routing means being cross-connected so that, in the event of a fault, control signals from the second channel are routed via the first routing means to the second drive means and/or control signals from the first channel are routed via the second routing means to the first drive means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
[0019] FIG. 1 shows a known form of choke drive assembly for a hydrocarbon extraction well;
[0020] FIG. 2 shows a modification of what is shown in FIG. 1 , being an example of the present invention;
[0021] FIG. 3 shows in more detail one of the electronic modules of FIG. 2 ;
[0022] FIGS. 4 and 5 show the switching of relays in modules for two chokes; and
[0023] FIG. 6 shows how redundancy is provided in control channels in an example of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] FIG. 1 shows, diagrammatically, a known form of drive assembly for a fluid control device, typically a choke, mounted downhole in a hydrocarbon extraction well. The output of the drive is a shaft 1 with a linear motion which operates the fluid control device D, typically a choke having a sliding slotted sleeve that controls fluid flow. The linear action of the shaft 1 is derived from the rotary motion of a motor via a screw arrangement. The assembly (as in GB 2350659) has two motors 2 and 3 coupled with a mechanism 4 , that provides the required linear output from the shaft 1 from either motor. The two motors provide greater availability in the event of the failure of one of them and are controlled and powered via separate feeds from a control system at a surface platform to the well. In the example shown, motor 2 is electric and motor 3 is hydraulic, thus continuing to provide availability in the case of failure of either the electric or hydraulic power sources or their feeds. The control of both the electric motor 2 and the hydraulic motor 3 is through an electronic communication system.
[0025] In the case of the hydraulic motor 3 , a hydraulic power supply on a line 5 is switched to the motor 3 by a DCV 6 , electrically operated by a downhole electronics module (DEM) 7 . The DEM 7 recognises and acts upon a digital message received from the control system via one of the feeds through an umbilical which is designated ‘Channel B’ (Ch B). Electric power to the DEM 7 is provided by a power supply unit (PSU) 8 which is provided with electric power via the same umbilical and is designated ‘Power B’
[0026] Likewise, in the case of the electric drive, the motor 2 is operated directly by another DEM 9 , which recognises and acts upon a digital message received from the control system via another feed in the umbilical and is designated ‘Channel A’ (Ch A). Electric power to the DEM 9 is provided by a PSU 10 which is fed with electric power via the same umbilical and is designated ‘Power A’.
[0027] Although the known system described above provides considerable redundancy, it could be considered as less than adequate when a plurality of fluid control devices D such as chokes are fitted downhole, in that a failure of electrical links between the devices could render the well inoperative. Thus, a system is desired that continues to provide redundancy in the event of such failures. Since both control signals and electric power are equally important in sustaining well control, this invention provides a solution to the failure of either or both.
[0028] In order to provide redundancy of power supply, an embodiment of the invention modifies the DEMs of FIG. 1 as shown in FIG. 2 , by the addition of power supply selection and isolation relay assemblies, the cross-connection between drives of the power supply units (PSUs), the feeding of both ‘Power A’ and ‘Power B’ to the relay assemblies and the feeding of both control channels Channel A and Channel B to the DEMs.
[0029] Referring to FIG. 2 , a modified DEM 1 for DCV 6 now includes a relay assembly 12 and likewise a modified DEM 13 for motor 2 includes a relay assembly 14 . Power from PSU 8 is applied to DEM 13 and power from PSU 10 is applied to DEM 1 , the latter using one of ‘Power A’ and ‘Power B’ and DEM 13 using the other of ‘Power A’ and ‘Power B’ in normal operation. Since the normal operation of the system is to operate each of the two drives from a different one of the two power sources, the cross-connected PSUs allow for selection of an alternative power source by a DEM.
[0030] The reason for the cross-connection of the PSUs 8 and 10 is to retain operation of the control to enable switching to an alternative power supply source in the event of failure of either a power source or a PSU. To illustrate this further, assume it was the case that PSU 10 powers the control logic electronics within DEM 13 (rather than DEM 11 ) which controls the selection of ‘Power A’ or ‘Power B’ by the relay unit 14 to feed the PSU 10 . Also assume that ‘Power A’ is powering the system. Now, if PSU 10 fails then the power to the control logic electronics in DEM 13 would disappear and thus it would be unable to select, as an alternative, ‘Power B’ to continue operation. By cross-connecting the PSUs 8 and 10 between the two drive systems and ensuring that, in normal operation, the control logic electronics within DEM 13 operates the relay unit 14 such that PSU 10 is fed with, say, ‘Power A’ and the control logic electronics within DEM 11 operates the relay unit 12 such that the PSU 8 is fed with ‘Power B’, then, in the event of either a PSU or power source failure, the control logic elements are still powered by the other source and thus able to continue to receive commands to switch the power source to sustain operation of at least one drive.
[0031] FIG. 3 shows the arrangement of the relays in the relay assembly of a modified DEM, i.e. item 12 or 14 of FIG. 2 . A latching relay 15 provides selection of the power supply, i.e. ‘Power A’ or ‘Power B’, under the control of the electronic part of the DEM. A latching relay 16 provides switching or isolation of the power feed output to another relay assembly on another choke. A latching relay 17 provides switching or isolation of power to the PSU, i.e. item 8 or 10 of FIG. 2 .
[0032] As shown in FIG. 2 , the choke carries two DEMs. When there is a plurality of chokes in a well, the relay assemblies are connected as illustrated in FIG. 4 . FIG. 4 shows relay assemblies 18 a and 19 a for a choke 20 and 18 b and 19 b for a choke 21 . Power supplies, ‘Power A’ and ‘Power B’, are connected to and routed through the two DEM relay assemblies as shown. The two output isolation relays 16 a of assemblies 18 a and 19 a respectively are connected to an identical arrangement of relay assemblies in the second choke 21 . FIG. 4 shows clearly which electronic section of the DEMs ( 11 a and 13 a for choke 20 and 11 b and 13 b for choke 21 ) controls each relay. The versatility of control and isolation allows availability of power to at least one of the choke drives in the event of a single power source failure or interconnection failure as illustrated by the example in FIG. 5 .
[0033] FIG. 5 shows, as an example, how power can be sustained to both DEMs in the second choke 21 , and any subsequent chokes (not shown in the figure), in the event of a short or open circuit of an electrical link 22 between the two chokes. With such a failure, a digital control message is sent to the DEM 11 a in choke 20 which operates relay 16 a in the relay assembly 19 a in the choke 20 . Operation of relay 16 a isolates choke 21 from the faulty link. This action is followed by a digital control message being sent to the DEM 11 b in choke 21 which operates the relay 15 b in relay assembly 19 b of choke 21 . This reconnects power from the ‘Power A’ so that both drives continue to operate in choke 21 .
[0034] It follows from analysis of the circuit that the failure of any one power link between the chokes or a failure of a power source can be circumvented by suitable operation of the appropriate relays. However this power supply architecture is of limited value unless the same versatility is available, in the event of a failure, for the communication links that control the relays and command the choke drive operation.
[0035] FIG. 6 shows a typical arrangement for the architecture of the communications system of a subsea well. Communication from the surface platform is duplicated via the umbilical (or via two umbilicals) as Ch A and Ch B. Typically, communication data is transmitted on the power feed and then extracted at the duplicated subsea electronic modules (SEM) 25 located on the well tree on the sea bed. The data is then transformed into the format required to communicate downhole to the choke drives by the interface units 26 . Each choke has two DEMs (DEM 1 A and DEM 1 B) which contain electronic circuitry that reconfigures the architecture in the case of a fault. These circuits are integrated into integrated circuits, each with four ports P 0 , P 1 , P 2 , P 3 .
[0036] Under normal, no fault, conditions the communications operates in ‘loop mode’, with simplex traffic, of frames of data with a token system. Each integrated circuit operates such that an input to P 0 is retransmitted from both P 0 and P 3 , and an input to P 3 is retransmitted from P 3 and P 0 . Thus communication is passed round the loop such that any choke can be operated from one channel or the other, in the event of a failure of one link between the chokes.
[0037] However, a much improved fault tolerant system is achieved by additional features in the integrated circuits with the ports cross-connected as shown. In the event of a fault, the integrated circuits are commanded to operate in half duplex mode and communicate as to the table below.
RECEIVE ON REPLY ON RE-TRANSMIT ON P0 P0 P3 P1 P1 P1 P2 P0 P2 P2 P3 P1 P3 P3 P2 P0
[0038] Thus in the half duplex mode each DEM will repeat data from the DEM above it, to the DEM below it, i.e. from port P 0 to P 3 . Similarly, each DEM will repeat data from the DEM below it to the DEM above, i.e. from port P 3 to P 0 . Data that is repeated on port P 3 of DEMs 3 A and 3 B can be ignored.
[0039] Because of the local cross-loop in each choke, each DEM will actually receive data on two ports. However, the data is delayed by an extra 1.5 bits from the companion DEM and is then not used unless there is a fault. Thus, for example, if there is a fault in the cable (short or open circuit) between DEM 1 A and DEM 2 A, then DEM 2 A receives its data on P 2 from DEM 2 B. DEM 2 A will continue to re-transmit to P 3 and P 1 , so data arrives at DEM 3 A port P 0 . Similarly, if a fault occurs between DEM 1 B and DEM 2 B, then DEM 2 B receives its data on P 2 from DEM 2 A. DEM 2 B will continue to re-transmit to P 3 and P 1 so data arrives at DEM 3 B port P 0 . It should be noted that the local cross links in each choke are not in a high stress environment and are thus unlikely to fail. It follows that any single fault between chokes is tolerated and that multiple faults are also tolerated, provided there is only one fault between chokes.
[0040] The combination of the described power and communication architecture substantially improves fault tolerance in the electrical control of subsea wells. | In apparatus for controlling a fluid production well, a control device D, such as a choke, located downhole is operable selectively by first and second drive means ( 2,3 ). First and second power supply means and first and second control channels (ChA, ChB) for control signals are provided for the first and second drive means, the arrangement being such that if one of the power supplies fails, the respective drive means is operable via the other power supply. First and second means (DEM 1 A, DEM 1 B) for routing control signals from the first and second channels respectively to the first and second drive means are provided, the routing means being interconnected so that, in the event of a fault, control signals from the second channel are routed via the first routing means to the second drive means and/or control signals from the first channel are routed via the second routing means to the first drive means. | 4 |
APPLICATION PRIORITY DATA
This application is a continuation of U.S. application Ser. No. 12/119,622, filed May 13, 2008, now U.S. Pat. No. 7,906,542, issued on Mar. 15, 2011, which in turn is a continuation-in-part of application U.S. application Ser. No. 11/873,841, filed on Oct. 17, 2007, which is a continuation-in part of U.S. application Ser. No. 11/135,651, filed on May 24, 2005, now abandoned, which is a continuation-in-part of PCT/EP04/12490, filed on Nov. 4, 2004, which claims priority to Italian application No. MI2003A002144 filed Nov. 7, 2003, all of which are incorporated by reference herein in their entirety, including any drawings.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to rifaximin polymorphic forms α, β and γ, the processes for their preparation and the use thereof in the manufacture of medicinal preparations.
2. Description of the Related Art
Rifaximin (INN; see The Merck Index, XIII Ed., 8304) is an antibiotic belonging to the rifamycin class, namely a pyrido-imidazo rifamycin described and claimed in Italian Patent IT 1154655, while EP 0161534 discloses and claims a process for its production starting from rifamycin O (The Merck Index, XIII Ed., 8301).
Both these patents generically describe the purification of rifaximin by crystallization in suitable solvents or solvent systems and summarily show in some examples that the resulting product can be crystallized from the 7:3 mixture of ethyl alcohol/water and dried both under atmospheric pressure and under vacuum. Neither information concerning the experimental conditions of crystallization and drying, nor any distinctive crystallographic characteristic of the obtained product are reported.
The presence of different polymorphs had not been ascertained and therefore the experimental conditions described in both patents had been developed with the aim of obtaining a homogeneous product having suitable purity from the chemical point of view, apart from the crystallographic aspects of the product itself.
It has now been unexpectedly found that some polymorphic forms of rifaximin exist whose formation depends on the solvent as well as on the conditions of time and temperature at which both crystallization and drying are carried out.
SUMMARY OF THE INVENTION
In one embodiment, a pharmaceutical composition is provided comprising rifaximin in polymorphic form α. In one embodiment, the C max is about 2 ng/ml. In a further embodiment, the C max is about 2.6 ng/ml. In one embodiment, the t max is about 9 hours. In a further embodiment, the t max is about 9.5 hours. In other embodiments, the AUC 0-24 h is about 13 ng·h/ml.
In another embodiment, the pharmaceutical composition provided comprising rifaximin in polymorphic form α has a water content of from between about 0% to about 3%. In one embodiment, the C max is about 2 ng/ml. In a further embodiment, the C max is about 2.6 ng/ml. In one embodiment, the t max is about 9 hours. In a further embodiment, the t max is about 9.5 hours. In other embodiments, the AUC 0-24 h is about 13 ng·h/ml.
In other embodiments, a pharmaceutical composition is provided comprising rifaximin in polymorphic form β. In one embodiment, the C max is about 1 ng/ml. In a further embodiment, the C max is about 1.1 ng/ml. In one embodiment, the t max is about 4 hours. In a further embodiment, the t max is about 9.5 hours. In other embodiments, the AUC 0-24 h is about 11 ng·h/ml. In one embodiment, the intrinsic dissolution rate of the rifaximin is about 0.01 mg/min/cm 2 .
In another embodiment, the pharmaceutical composition provided comprising rifaximin in polymorphic form β has a water content of from between greater than about 4.5%. In one embodiment, the C max is about 1 ng/ml. In a further embodiment, the C max is about 1.1 ng/ml. In one embodiment, the t max is about 4 hours. In a further embodiment, the t max is about 9.5 hours. In other embodiments, the AUC 0-24 h is about 11 ng·h/ml. In one embodiment, the intrinsic dissolution rate is about 0.01 mg/min/cm 2 .
In other embodiments, a pharmaceutical composition is provided comprising rifaximin in polymorphic form γ. In one embodiment, the C max is about 670 ng/ml. In a further embodiment, the C max is about 668 ng/ml. In one embodiment, the t max is about 2 hours. In a further embodiment, the t max is about 2.3 hours. In other embodiments, the AUC 0-24 h is about 4000 ng·h/ml.
In another embodiment, the pharmaceutical composition provided comprising rifaximin in polymorphic form γ has a water content of from between about 1% to about 2%. In one embodiment, the C max is about 670 ng/ml. In a further embodiment, the C max is about 668 ng/ml. In one embodiment, the t max is about 2 hours. In a further embodiment, the t max is about 2.3 hours. In other embodiments, the AUC 0-24 h is about 4000 ng·h/ml.
Another embodiment of the invention provides a pharmaceutical composition comprising one or more of a form α, a form β, and a form γ polymorph of rifaximin and a pharmaceutically acceptable carrier. In one embodiment, the pharmaceutical composition further comprises excipients. In a further embodiment, the excipients are one or more of a diluting agent, binding agent, lubricating agent, disintegrating agent, colouring agent, flavouring agent or sweetening agent.
In one embodiment, the composition is formulated for selected coated and uncoated tablets, hard and soft gelatine capsules, sugar-coated pills, lozenges, wafer sheets, pellets and powders in a sealed packet.
One embodiment of the invention provides a pharmaceutical composition consisting essentially of rifaximin in polymorphic form α.
Another embodiment of the invention provides a pharmaceutical composition consisting essentially of rifaximin in polymorphic form β.
A further embodiment of the invention provides a pharmaceutical composition consisting essentially of rifaximin in polymorphic form γ.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a powder X-ray diffractogram of rifaximin polymorphic form α.
FIG. 2 is a powder X-ray diffractogram of rifaximin polymorphic form β.
FIG. 3 is a powder X-ray diffractogram of rifaximin polymorphic form γ.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates to the form α, the form β and the form γ of the antibiotic known as rifaximin (INN), the processes for their preparation and the use thereof in the manufacture of medicinal preparations for the oral or topical route.
The process of the present invention comprises reacting one molar equivalent of rifamycin O with an excess of 2-amino-4-methylpyridine, preferably from 2.0 to 3.5 molar equivalents, in a solvent mixture consisting of water and ethyl alcohol in volumetric ratios between 1:1 and 2:1, for a time between 2 and 8 hours at a temperature between 40° C. and 60° C.
After completion of the reaction, the reaction mass is cooled to room temperature and added with a solution of ascorbic acid in a mixture of water, ethyl alcohol and aqueous concentrated hydrochloric acid, under strong stifling, in order to reduce the small amount of oxidized rifaximin that forms during the reaction. Finally the pH is adjusted to about 2.0 by further addition of hydrochloric acid concentrated aqueous solution, in order to better remove the excess of 2-amino-4-methylpyridine used in the reaction. The suspension is filtered and the resulting solid is washed with the same solvent mixture water/ethyl alcohol as used in the reaction. Such semifinished product is called “raw rifaximin”.
The raw rifaximin can be directly submitted to the subsequent purification step. Alternately, in case long times of preservation of the semifinished product are expected, the raw rifaximin can be dried under vacuum at a temperature lower than 65° C. for a time between 6 and 24 hours, such semifinished product is called “dried raw rifaximin”.
The resulting raw rifaximin and/or dried raw rifaximin are purified by dissolution in ethyl alcohol at a temperature between 45° C. and 65° C., followed by crystallization by addition of water, preferably in weight amounts between 15% and 70% to the weight amount of ethyl alcohol used for the dissolution, and by keeping the resulting suspension at a temperature between 50° C. and 0° C. under stirring during a time between 4 and 36 hours.
The suspension is filtered and the obtained solid is washed with water and dried under vacuum or under normal pressure, optionally in the presence of a drying agent, at a temperature between room temperature and 105° C. for a time between 2 and 72 hours.
The achievement of the α, β and γ forms depends on the conditions selected for the crystallization. In particular, the composition of the solvent mixture used for the crystallization, the temperature at which the reaction mixture is kept after the crystallization and the period of time at which that temperature is kept, have proven to be critical.
More precisely, rifaximin γ is obtained when the solution is brought to a temperature between 28° C. and 32° C. to start precipitation and the resulting suspension is further cooled to 0° C. and kept at this temperature for a time between 6 and 24 hours.
The suspension is filtered, the solid is washed with demineralized water and is dried to a water content between 1.0% and 2.0%.
The α and β rifaximins are obtained when the temperature is first brought to a value between 28° C. and 32° C. in order to start crystallization, then the suspension is brought to a temperature between 40° C. and 50° C. and kept at this value for a time between 6 and 24 hours, then the suspension is quickly cooled to 0° C. in 15 minutes to one hour, then is filtered, the solid is washed with water and then dried.
The drying steps plays an important role in obtaining the rifaximin α and β polymorphic forms and has to be monitored by a method suited to water dosage, such as the Karl Fischer method, in order to check the amount of remaining water present in the product under drying.
Rifaximin α or rifaximin β are obtained by drying to different final water contents, be they higher or lower than 4.5%, and do not depend on the experimental conditions of pressure and temperature at which such critical water contents are achieved. In fact, the two polymorphic forms, with higher or lower water content, can be obtained by drying under vacuum or at atmospheric pressure, at room temperature or at high temperatures, optionally in the presence of drying agents, provided that the drying is prolonged for the time necessary to reach the water content characteristic for each polymorphic form.
The polymorphic form β is obtained when the drying of the product crystallized and washed with water is stopped at water contents higher than 4.5%, measured by Karl Fischer, preferably between 5.0% and 6.0%, while the polymorphic form α is obtained when drying is continued until water contents lower than 4.5%, preferably between 2.0% and 3.0%.
Both the form γ and the forms α and β of rifaximin are hygroscopic, they reversibly absorb water in time in the presence of suitable environmental conditions of pressure and humidity and are susceptible of transformation from one form into another.
When the polymorphic form α is kept under conditions of relative humidity higher than 50% for a time between 12 and 48 hours, it changes into the polymorphic form β, which in its turn is transformed into the polymorphic form α upon drying to a water content lower than 4.5%, preferably comprised between 2.0% and 3.0%.
Another type of transition exists between the form γ and the forms α and β, depending upon the temperatures kept during the phase of precipitation of rifaximin.
In particular, the form γ turns into the forms α or β when a suspension of the form γ of rifaximin is kept in an ethyl alcohol/water 7:3 (V/V) solvent mixture at a temperature between 38° C. and 50° C. under strong stifling for a prolonged time, preferably comprised between 6 and 36 hours.
After filtration and washing with demineralized water, drying to a water content higher than 4.5%, preferably between 5.0% and 6.0%, affords the polymorphic form β, while when drying is continued to a water content lower than 4.5%, preferably between 2.0% and 3.0%, gives the form α.
Rifaximins α and β can in their turn change into rifaximin γ by dissolution in ethyl alcohol and treatment of the resulting solution as previously described for the preparation of the form γ.
These transitions from one form into another are very important for the invention, as they can be provide an alternative process for the preparation of the form desired for the production of the medicinal preparations. Therefore, the process that allows to transform rifaximin γ into rifaximin α or β in a valid industrial manner, or vice versa rifaximin β into rifaximin α, are important parts of the invention.
The process concerning the transformation of rifaximin γ into rifaximin α or rifaximin β comprises suspending rifaximin γ in a solvent mixture consisting of ethyl alcohol/water in 7:3 volumetric ratio, warming the suspension to a temperature between 38° C. and 50° C. and keeping it at this temperature under strong stifling for a time between 6 and 36 hours. The suspension is then filtered, the solid is washed with water and dried; the polymorphic form β is obtained when drying is carried out to a water content between 5.0% and 6.0% measured by the Karl Fischer method, while the polymorphic form α is obtained when drying is continued to a water content between 2.0% and 3.0%.
The process for the preparation of the form γ starting from rifaximin α or β comprises dissolving the α or β form in ethyl alcohol under stifling, at a temperature between 50° C. and 60° C., adding demineralized water to an ethyl alcohol/water 7:3 volumetric ratio, cooling the solution to 30° C. under strong stifling, cooling the precipitate to 0° C. and keeping the suspension under stirring at 0° C. for a time between 6 and 24 hours. The suspension is then filtered, the solid is washed with water and dried to a water content lower than 2.0% thereby obtaining rifaximin γ.
The process for the transformation of the form α into the form β consists in keeping powder rifaximin α in an ambient having relative humidity higher than 50% for the time required to obtain a water content in the powder higher than 4.5%, which time is usually between 12 and 48 hours.
The process for the transformation of the form β into the form α consists in drying powder rifaximin β under vacuum or under conditions of normal pressure, optionally in the presence of a drying agent, at a temperature between the room temperature and 105° C., for a time between 2 and 72 hours, to obtain a water content in the powder lower than 4.5%, preferably between 2.0% and 3.0%.
It is evident from what stated above that during preservation of the product particular care should be taken so that the ambient conditions do not affect the water content of the product, by preserving the product in an environment having controlled humidity or in closed containers that allow no significant exchanges of water with the exterior.
The rifaximin α polymorph is characterized by a water content lower than 4.5%, preferably between 2.0% and 3.0% and by a powder X-ray diffractogram (reported in FIG. 1 ) which shows peaks at the values of the diffraction angles 2θ of 6.6°; 7.4°; 7.9°; 8.8°; 10.5°; 11.1°; 11.8°; 12.9°; 17.6°; 18.5°; 19.7°; 21.0°; 21.4°; 22.1°. The rifaximin β polymorph is characterized by a water content higher than 4.5%, preferably between 5.0% and 6.0%, and by a powder X-ray diffractogram (reported in FIG. 2 ) which shows peaks at the values of the diffraction angles 2θ of 5.4°; 6.4°; 7.0°; 7.8°; 9.0°; 10.4°; 13.1°; 14.4°; 17.1°; 17.9°; 18.3°; 20.9°.
The rifaximin γ polymorph is characterized by a powder X-ray diffractogram much poorer because of the poor crystallinity; the significant peaks are at the values of the diffraction angles 2θ of 5.0°; 7.1°; 8.4° as reported in FIG. 3 .
The diffractograms have been carried out using a Philips X′Pert instrument fitted with Bragg-Brentano geometry and under the following working conditions:
X-ray tube: Copper
Radiation used: K (α1), K (α2)
Tension and current of the generator: KV 40, mA 40
Monocromator: Graphite
Step size: 0.02
Time per step: 1.25 seconds
Starting and final angular 2θ value: 3.0°÷30.0°
The evaluation of the water content in the analyzed samples has always been carried out by means of the Karl Fischer method.
Rifaximin α, rifaximin β and rifaximin γ significantly differ from each from other also in terms of bioavailability and intrinsic dissolution.
A bioavailability study of the three polymorphs has been carried out on Beagle female dogs, by feeding them orally with a dose of 100 mg/kg of one of the polymorphs, collecting blood samples from the jugular vein of each animal before each dosing and 1, 2, 4, 6, 8 and 24 hours after each dosing, transferring the samples into tubes containing heparin and separating the plasma by centrifugation.
The plasma has been assayed for rifaximin on the validated LC-MS/MS (Liquid Chromatography-Mass Spectrometry/Mass Spectrometry) method and the maximum plasma concentration observed (C max ), the time to reach the (C max ) (t max ), and the area under the concentration-time curve (AUC) have been calculated.
The experimental data reported in the following table 1 clearly show that rifaximin α and rifaximin β are negligibly absorbed, while rifaximin γ is absorbed at a value (C max =0.668 μg/ml) comprised in the range of from 0.1 to 1.0 μg/ml.
TABLE 1
Pharmacokinetic parameters for rifaximin polymorphs following
single oral administration of 100 mg/kg by capsules to female dogs.
C max
AUC 0-24
ng/ml
t max h
ng · h/ml
Mean
Mean
Mean
Polimorph α
2.632
9.5
13
Polimorph β
1.096
4
11
Polimorph γ
668.22
2.25
3908
Intrinsic dissolution tests have been carried out on each of the three polymorphs according to the method described in the monograph 1087 at pages 2512-2513 of the USP (U.S. Pharmacopoeia) 27, clearly showing significant differences among rifaximin α, rifaximin β and rifaximin γ.
A sample of each rifaximin polymorph has been put into a die and compressed at 5 tons by means of a punch of a hydraulic press to obtain a compacted pellet.
The die-holder containing the compacted pellet has then been mounted on a laboratory stirring device, immersed in a dissolution medium and rotated by means of the stirring device.
The test, carried out in a dissolution medium made of aqueous phosphate buffer at ph 7.4 and of sodium lauryl sulfate at a temperature of 37±0.5° C., has shown significant differences among the intrinsic dissolution rates exhibited by the three polymorphs.
Rifaximin α has shown disintegration of the compacted pellet within 10 minutes so that it has not been possible to calculate the value of its intrinsic dissolution, while the intrinsic dissolution of rifaximin γ has been about ten times as much that of rifaximin β in accordance with its bioavailability which is more than hundred times as much that of rifaximin β.
The above experimental results further point out the differences existing among the three rifaximin polymorphs.
The forms α, β and γ can be advantageously used in the production of medicinal preparations having antibiotic activity, containing rifaximin, for both oral and topical use. The medicinal preparations for oral use will contain rifaximin α or β or γ together with the usual excipients, for example diluting agents such as mannitol, lactose and sorbitol; binding agents such as starches, gelatines, sugars, cellulose derivatives, natural gums and polyvinylpyrrolidone; lubricating agents such as talc, stearates, hydrogenated vegetable oils, polyethylenglycol and colloidal silicon dioxide; disintegrating agents such as starches, celluloses, alginates, gums and reticulated polymers; coloring, flavoring and sweetening agents.
The present invention relates to all of the solid preparations administrable by the oral route, for instance coated and uncoated tablets, of soft and hard gelatine capsules, sugar-coated pills, lozenges, wafer sheets, pellets and powders in sealed packets.
The medicinal preparations for topical use will contain rifaximin α or β or γ together with usual excipients, such as white petrolatum, white wax, lanoline and derivatives thereof, stearylic alcohol, propylene glycol, sodium lauryl sulfate, ethers of fatty polyoxyethylene alcohols, esters of fatty polyoxyethylene acids, sorbitan monostearate, glyceryl monostearate, propylene glycol monostearate, polyethylene glycols, methylcellulose, hydroxy propylmethylcellulose, sodium carboxymethylcellulose, colloidal aluminium and magnesium silicate, sodium alginate.
The present invention relates to all of the topical preparations, for instance ointments, pomades, creams, gels and lotions.
The invention is further illustrated by some examples. Such examples are not to be taken as a limitation of the invention, it is in fact evident that the α, β and γ forms can be obtained by suitably combining between them the above mentioned conditions of crystallization and drying.
EXAMPLE 1
Preparation of Raw Rifaximin and of Dried Raw Rifaximin
In a three-necked flask equipped with mechanic stirrer, thermometer and reflux condenser, 120 ml of demineralized water, 96 ml of ethyl alcohol, 63.5 g of rifamycin O and 27.2 g of 2-amino-4-methylpyridine are loaded in succession at room temperature. After loading, the mass is heated at 47±3° C. and kept under stirring at this temperature for 5 hours, then is cooled to 20±3° C. and, during 30 minutes, is added with a mixture, prepared separately, of 9 ml of demineralized water, 12.6 ml of ethyl alcohol, 1.68 g of ascorbic acid and 9.28 g of aqueous concentrated hydrochloric acid. After completion of the addition, the mass is kept under stirring for 30 minutes at an inner temperature of 20±3° C. then 7.72 g of concentrated hydrochloric acid are dripped until a pH equal to 2.0, while keeping said temperature.
After completion of the addition, the mass is kept under stifling for 30 minutes, keeping an inner temperature of 20° C., then the precipitate is filtered and washed with a mixture of 32 ml of demineralized water and of 25 ml of ethyl alcohol. The resulting “raw rifaximin” (89.2 g) is dried under vacuum at room temperature for 12 hours obtaining 64.4 g of “dried raw rifaximin” which shows a water content of 5.6% and a diffractogram corresponding to the polymorphic form β. The product is further dried under vacuum until constant weight to afford 62.2 g of dried raw rifaximin having a water content of 2.2%, whose diffractogram corresponds to the polymorphic form α.
The product is hygroscopic and the obtained polymorphic form is reversible: the polymorphic form α absorbs water from atmospheric humidity, depending on the relative humidity and the exposure time. When the water content absorbed by the polymorphic form cc becomes higher than 4.5%, polymorphous cc turns to polymorphous β. This in its turn loses part of water by drying, changing into the polymorphic form α when a water content between 2.0% and 3.0% is reached.
EXAMPLE 2
Preparation of Rifaximin γ
163 ml of ethyl alcohol and 62.2 g of dried raw rifaximin are loaded at room temperature into a three-necked flask equipped with mechanic stirrer, thermometer and reflux condenser. The suspension is heated at 57±3° C. under stifling until complete dissolution of the solid, and added with 70 ml of demineralized water at this temperature in 30 minutes. After completion of the addition the temperature is brought to 30° C. in 40 minutes and kept at this value until complete crystallization, then the temperature is further lowered to 0° C. in 2 hours and kept at this value for 6 hours. The suspension is then filtered and the solid is washed with 180 g of demineralized water and dried under vacuum at room temperature until constant weight, thereby obtaining 52.7 g of pure rifaximin γ having water content of 1.5%.
The form γ is characterized by a powder X-ray diffractogram showing significant peaks at diffraction angles 2θ of 5.0°; 7.1°; 8.4°.
EXAMPLE 3
Preparation of Rifaximin α
62.2 Grams of dried raw rifaximin and 163 ml of ethyl alcohol are loaded at room temperature into a three-necked flask equipped with mechanic stirrer, thermometer and reflux condenser. The suspension is heated at 57±3° C. until complete dissolution of the solid and then 70 ml of demineralized water are added at this temperature during 30 minutes. After completion of the addition, the temperature is brought to 30° C. during 40 minutes and is kept at this value until plentiful crystallization. The temperature of the suspension is then brought to about 40° C. and kept at this value during 20 hours under stifling; then the temperature is decreased to 0° C. in 30 minutes and the suspension is immediately filtered. The solid is washed with 180 ml of demineralized water and dried under vacuum at room temperature until constant weight, thereby obtaining 51.9 g of rifaximin form α are obtained with a water content equal to 2.5% and a powder X-ray diffractogram showing peaks at values of angles 2θ of 6.6°; 7.4°; 7.9°; 8.8°; 10.5°; 11.1°; 11.8°; 12.9°; 17.6°; 18.5°; 19.7°; 21.0°; 21.4°; 22.1°.
EXAMPLE 4
Preparation of Rifaximin α
89.2 Grams of raw rifaximin and 170 ml of ethyl alcohol are loaded at room temperature into a three-necked flask equipped with mechanic stirrer, thermometer and reflux condenser, then the suspension is heated at 57±3° C. until complete dissolution of the solid. The temperature is brought to 50° C. and then 51.7 ml of demineralized water are added at this temperature during 30 minutes. After completion of the addition the temperature is brought to 30° C. in one hour and the suspension is kept for 30 minutes at this temperature obtaining a plentiful crystallization. The temperature of the suspension is brought to 40° C. and kept at this value during 20 hours under stirring and then further lowered to 0° C. during 30 minutes after which the suspension is immediately filtered. The solid is washed with 240 ml of demineralized water and dried under vacuum at 65° C. until constant weight thereby obtaining 46.7 g of rifaximin α with a water content equal to 2.5%.
EXAMPLE 5
Preparation of Rifaximin α
Example 3 is repeated, but increasing to 50° C. the temperature at which the suspension is kept and lowering to 7 hours the time in which the suspension is kept at this temperature. The product obtained is equal to that of example 3.
EXAMPLE 6
Preparation of Rifaximin β
The crystallization of the dried raw rifaximin is carried out according to the process described in example 3. Drying under vacuum at room temperature is monitored by Karl Fischer and stopped when the water content reaches 5.0%: 52.6 g of rifaximin β are obtained characterized by a powder X-ray diffractogram showing peaks at values of angles 2θ of 5.4°; 6.4°; 7.0°; 7.8°; 9.0°; 10.4°; 13.1°, 14.4°; 17.1°; 17.9°; 18.3°; 20.9°.
EXAMPLE 7
Preparation of Rifaximin α Starting from Rifaximin γ
5 Grams of rifaximin γ are suspended in a mixture of 13 ml of ethyl alcohol and 5.6 ml of water and the suspension is heated at 40° C. during 24 hours under stirring in a 50 ml flask equipped with condenser, thermometer and mechanic stirrer. The suspension is then filtered and the solid is washed with water, then dried under vacuum at room temperature until constant weight. 4 Grams of rifaximin are obtained showing a powder X-ray diffractogram corresponding to that of the polymorphic form α and a water content equal to 2.6%.
EXAMPLE 8
Preparation of Rifaximin γ Starting from Rifaximin α
15 Grams of rifaximin form α and 52.4 ml of ethyl alcohol are loaded into a 250 ml three-necked flask equipped with reflux condenser, thermometer and mechanical stirrer; the suspension is heated under stirring at the temperature of 50° C. until complete dissolution of the solid.
The clear solution is added with 22.5 ml of water in 30 minutes under stirring, cooled to 30° C. and kept at this temperature for 30 minutes. The formed suspension is cooled to 0° C. under strong stirring and kept at this temperature during 6 hours. After this time, part of the suspension is taken, filtered, washed with demineralized water and dried under vacuum at 30° C. until constant weight.
The resulting product, 3.7 g, shows a diffractogram consistent with that of the form 7 and a water content of 1.7%.
The remaining part of the suspension is kept at 0° C. for further 18 hours under strong stirring and then is filtered, washed with demineralized water and dried at 30° C. under vacuum until constant weight. 9 Grams of product showing a diffractogram consistent with that of the form γ and a water content equal to 1.6% are obtained.
EXAMPLE 9
Preparation of Rifaximin α Starting from Rifaximin β
5 Grams of rifaximin β having a water content equal to 5.0% are dried under vacuum at +30° C. during 8 hours obtaining 4.85 g of rifaximin α having a water content equal to 2.3%.
EXAMPLE 10
Preparation of Rifaximin β Starting from Rifaximin α
5 Grams of rifaximin α having a water content equal to 2.5% are kept during 40 hours in an atmosphere containing a relative humidity equal to 56% made by means of a saturated aqueous solution of calcium nitrate tetrahydrate. 5.17 Grams of rifaximin β with a water content equal to 5.9% are obtained after this time.
EXAMPLE 11
Bioavailability in Dogs by Oral Route
Twelve 20 week pure-bred Beagle females dogs, and weighing between 5.0 and 7.5 kg, have been divided into three groups of four.
The first of these three groups has been treated with rifaximin α, the second with rifaximin β and third with rifaximin γ according to the following procedure.
Each dog received orally 100 mg/kg of one of the rifaximin polymorphs in gelatin capsules and 2 ml blood samples were collected from the jugular vein of each animal before each administration and 1, 2, 4, 6, 8 and 24 hours after the administration. Each sample was transferred into an heparinized tube and was centrifuged; the plasma was divided into 500 two aliquots and frozen at −20° C.
The rifaximin contained in the plasma was assayed by means of the validated LC-MS/MS method and the following parameters were calculated according to standard non-compartmental analysis:
C max =maximum plasma concentration of rifaximin observed in the plasma;
T max =time at which the C max is reached;
AUC=area under the concentration-time curve calculated through the linear trapezoidal rule.
The results reported in the following table 2 clearly show how the rifaximin γ is very much more absorbed, more than 102 times, in respect of rifaximin α and rifaximin β which are practically not absorbed.
TABLE 2
Pharmacokinetic parameters for rifaximin polymorphs following
single oral administration of 100 mg/kg by capsules to female dogs.
C max
AUC 0-24
ng/ml
t max h
ng · h/ml
Mean
Mean
Mean
rifaximin α
2.632
9.5
13
rifaximin β
1.096
4
11
rifaximin γ
668.22
2.25
3908
EXAMPLE 12
Intrinsic Dissolution Test
A sample of 100 mg of each rifaximin polymorph was submitted to the intrinsic dissolution test carried out as described in the monograph 1087 at pages 2512-2513 of the USP (U.S. Pharmacopoeia) 27.
100 Milligrams of a rifaximin polymorph were put into a die and compressed for 1 minute under a pressure of 5 tons by means of a punch in a hydraulic press.
A compacted pellet was formed in the die with a single face of defined area exposed on the bottom of the die so that from 50% to 75% of the compacted pellet could dissolve in an appropriate dissolution medium.
The holder containing the die was mounted on a laboratory stifling device, immersed in a glass vessel containing a dissolution medium and rotated at a rotation speed of 100 rpm by means of the stifling device, while keeping the temperature of the dissolution medium at 37±0.5° C. The dissolution medium contained in the glass vessel consisted of 1000 ml of 0.1 M aqueous phosphate buffer pH 7.4 containing 4.5 g of sodium lauryl sulfate and was kept at 37±0.5° C. for the whole duration of the test.
Samples of 2 ml of solution were taken after 15, 30, 45 and 60 minutes from the start of the dissolution procedure and analyzed by HPLC for the amount of rifaximin dissolved.
The sample containing rifaximin α systematically showed disintegration of the compacted pellet within 10 minutes and said phenomenon was also present at lower concentrations (0.1% and 0.3%) of sodium lauryl sulfate and even in absence of said surfactant, so that the value of its intrinsic dissolution could not be calculated.
The intrinsic dissolution of rifaximin γ was about ten times as much that of rifaximin β at every time, as it can be inferred by the experimental results shown in the following table 3.
TABLE 3
Intrinsic dissolution in 0.1M aqueous phosphate buffer pH 7.4
with 0.45% sodium lauryl sulfate
Rifaximin dissolved
(mg/cm 2 )
Time (min)
β polymorph
γ polymorph
15
0.28
2.46
30
0.50
4.52
45
0.72
6.44
60
0.94
9.04
Intrinsic dissolution
0.0147
0.1444
rate (mg/min/cm 2 ) | Crystalline polymorphous forms of rifaximin (INN), referred to as rifaximin α and rifaximin β, and a poorly crystalline form referred to as rifaximin γ, useful in the production of medicaments containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a fixed temperature and for a fixed period of time, followed by a drying under controlled conditions until reaching a precise water content in the end product, are the object of the invention. | 2 |
RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser. No. 13/238,993, filed Sep. 21, 2011, now U.S. Pat. No. 8,332,048, which is a divisional of U.S. application Ser. No. 11/740,507, filed Apr. 26, 2007, now U.S. Pat. No. 8,099,172, which claims the benefit of U.S. Provisional Application No. 60/745,882, filed Apr. 28, 2006, the disclosures of which are fully incorporated herein by reference for all purposes.
BACKGROUND
[0002] Neurostimulation systems are devices that generate electrical pulses and deliver the pulses to nerve tissue to treat a variety of disorders. Spinal cord stimulation (SCS) is an example of neurostimulation in which electrical pulses are delivered to nerve tissue in the spine for the purpose of chronic pain control. While a precise understanding of the interaction between the applied electrical energy and the nervous tissue is not fully appreciated, it is known that application of an electrical field to spinal nervous tissue (i.e., spinal nerve roots and spinal cord bundles) can effectively mask certain types of pain transmitted from regions of the body associated with the stimulated nerve tissue. Specifically, applying electrical energy to the spinal cord associated with regions of the body afflicted with chronic pain can induce “paresthesia” (a subjective sensation of numbness or tingling) in the afflicted bodily regions. Thereby, paresthesia can effectively mask the transmission of non-acute pain sensations to the brain.
[0003] Neurostimulation systems typically include a pulse generator and one or several leads. The pulse generator is the device that generates the electrical pulses. The pulse generator is typically implanted within a subcutaneous pocket created under the skin by a physician. The leads are used to conduct the electrical pulses from the implant site of the pulse generator to the targeted nerve tissue. The leads typically include a lead body of an insulative polymer material with embedded wire conductors extending through the lead body. Electrodes on a distal end of the lead body are coupled to the conductors to deliver the electrical pulses to the appropriate nerve tissue.
[0004] Stimulation paddle leads dispose a plurality of electrodes (for example, two, four, eight, or sixteen) arranged in one or more columns on a paddle structure. It is typical that implanted SCS paddles are transversely centered over the physiological midline of a patient. In such position, multiple columns of electrodes are well suited to address both unilateral and bilateral pain. A multi-column SCS paddle also enables reliable positioning of a plurality of electrodes that does not deviate over time. In particular, the probability of migration of an SCS paddle after implantation is significantly lower than the probability of migration of percutaneous leads. Additionally, SCS paddles are capable of being sutured in place.
[0005] However, given the dimensions of conventional SCS paddles, a surgical procedure is necessary for implantation. The surgical procedure (a “partial laminectomy”) requires the resection and removal of certain vertebral structures to allow both access to the dura and proper positioning of the SCS paddle. The invasive nature of the surgical procedure requires some amount of time for patient recovery and, in some cases, could cause long-term complications for the patient. Additionally, due to the relatively complicated nature of the surgical procedure, the procedure is typically performed by a neurosurgeon.
[0006] Additionally, it is noted that typical assembly procedures for electrically coupling a lead body to a paddle structure are not only cumbersome and expensive, but also create a number of natural, easy breakage points. Specifically, conventional couplings between lead bodies and paddle structures involve welding a jumper wire between contacts and conductive wires of the lead body. Accordingly, conventional paddle lead fabrication methods may involve undue expense and lower than desired manufacturing yields.
SUMMARY
[0007] In one embodiment, a method of fabricating an implantable stimulation paddle comprises: providing a sheet of conductive material coupled to a first insulative layer; laser removing portions of the conductive material to form a pattern of conductive material, the pattern of conductive material including a plurality of isolated metal traces; providing a second insulative layer over the pattern of conductive material so that the pattern of conductive material is interposed between the first and second insulative layers; and exposing portions of the metal traces to form electrodes on the paddle for delivering electrical stimulation.
[0008] In another embodiment, an implantable medical lead for delivering electrical energy to stimulate a patient comprises: a lead body comprising a plurality of helically wound conductive wires embedded in insulative material; and a paddle comprising a metal layer disposed between insulative layers, wherein a plurality of electrically isolated metal traces are patterned in the metal layer, each metal trace comprises an electrode exposed through one or several insulative layers, and each electrode is electrically coupled to a conductive wire of the lead body.
[0009] In another embodiment, a system for electrically stimulating a patient comprises: an implantable pulse generator (IPG) for generating electrical stimulation; a lead body comprising a plurality of helically wound conductive wires, embedded in insulative material, for conducting electrical stimulation from the IPG; and a paddle comprising a metal layer disposed between insulative layers, wherein a plurality of electrically isolated metal traces are patterned in the metal layer, each metal trace comprises an electrode exposed through one or several insulative layers, and each electrode is electrically coupled to a conductive wire of the lead body.
[0010] In another embodiment, a method comprises: providing a lead body having a plurality of conductive wires, wherein the plurality of conductive wires are helically wound at a wire spacing pitch; providing a stimulation paddle, the stimulation paddle comprising a metal layer between insulative layers, wherein a plurality of electrically isolated metal traces are patterned in the metal layer, each metal trace comprises a contact and an electrode exposed through one or several insulative layers, and the contacts of the metal traces are disposed together on the stimulation paddle and spaced according to the wire spacing pitch; placing the lead body in contact with the stimulation paddle such that an exposed segment of the lead body abuts the contacts of the metal traces; and transmitting energy onto each contact so that the respective contact becomes welded to an abutting conductive wire of the medical lead thereby electrically coupling the abutting conductive wire to a respective electrode of the stimulation paddle.
[0011] The foregoing has outlined rather broadly certain features and/or technical advantages in order that the detailed description that follows may be better understood. Additional features and/or advantages will be described hereinafter. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the appended claims. The novel features, both as to organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.
[0013] FIG. 1 is an expanded top perspective view of a stimulation paddle shaped work piece, at an early stage in the production process.
[0014] FIG. 2 is an expanded top perspective view of a of the work piece of FIG. 1 , at a further stage in the production process.
[0015] FIG. 3 is an expanded top view of a connector portion of the work piece of FIG. 1 , as indicated by the rectangle marked “FIG. 3 ” in FIG. 2 .
[0016] FIG. 4 is an expanded top view of the connector portion of FIG. 3 showing the result of further machining of the work piece of FIG. 1 , after removal of a window of dielectric material to expose a portion of the traces, which had been entirely embedded.
[0017] FIG. 5 is a plan view of a completed SCS paddle, resulting from the manufacturing process shown in FIGS. 14 .
[0018] FIG. 6 is an expanded top view of the connector portion of FIG. 5 placed with the window over a portion of a multiconductor cable.
[0019] FIG. 7 is an expanded top view of the connector portion and lead body of FIG. 5 , showing the exposed traces of the connector portion after being laser welded to the underlying conductive wires of the lead body.
[0020] FIG. 8 is an expanded top view of a connector portion of an alternative preferred embodiment of a stimulation paddle work piece, at the same stage of manufacturing as is the work piece of FIG. 4 .
[0021] FIG. 9 shows an alternative preferred embodiment of a paddle head having a polymeric coating on the back side of the connection contact sites, which are spaced further apart from each other than in previously shown embodiments.
[0022] FIG. 10 shows an alternative preferred embodiment of a paddle head that is similar in concept to the paddle of FIG. 9 , but is adapted for the case in which the paddle is positioned perpendicular to the lead body.
DETAILED DESCRIPTION
[0023] One preferred embodiment takes the form of a method of making a spinal cord stimulation lead in the form of a paddle for stimulation of tissue (e.g., an “SCS paddle”). Referring to FIG. 1 , in a preferred method, an SCS paddle work piece 10 begins to take form as a thin layer of nervous-tissue-compatible conductive metal 14 adhered or otherwise coupled to a layer of nervous-tissue-compatible dielectric material 12 . The shape of the work piece 10 can be described as including a body 15 , a neck 17 and a head 19 .
[0024] Laser 16 is used to create a set of traces 18 (not completed in FIG. 1 ) by forming separating trenches 21 in metal layer 14 . Sufficient power is applied by laser 16 to ablate a small portion of the metal layer 14 preferably without ablating through the layer of dielectric material 12 . Once completed, each trace 18 is electrically isolated from each other trace 18 . Also, each trace 18 joins an electrode site 20 in body 15 to a device contact 28 ( FIG. 4 ), in the form of a finger, in head 19 .
[0025] Referring to FIG. 2 , an additional layer of nervous-tissue-compatible dielectric material 22 is then added on top of metal layer 14 , thereby covering electrode sites 20 , traces 18 ( FIG. 3 ) and device contacts 28 . A solid film can be adhered to metal layer 14 . Additionally or alternatively, a spin coat of insulative material could be applied to metal layer 14 . Layer 22 is then patterned with a second laser 16 ′ (adapted for machining dielectric material) to create a set of apertures 24 , which reveal the electrode sites 20 . In an alternative preferred embodiment, the same laser is used for both removing metal and dielectric material. Also, in alternative embodiments, the electrode sites 20 could be exposed using manual or other mechanical means.
[0026] Referring to FIGS. 3 and 4 , a window 26 is then created by laser 16 ′, revealing the device electrical contacts 28 . The completed SCS paddle 10 is shown in FIG. 5 . Referring to FIG. 6 , SCS paddle 10 is then placed over a medical lead 30 , so that the device electrical contacts 28 are each aligned with and placed over a conductive wire 32 of lead 30 . At this point, the insulation of lead 30 has been partially removed to expose conductive wires 32 which are co-located with contacts 28 . It shall be appreciated that the relative dimensions of the contacts 28 , lead 30 , and conductive wires 32 are not depicted to scale in FIG. 6 .
[0027] A laser beam, from the first laser 16 ( FIG. 1 ), is then focused so that part of its footprint covers a part of a device electrical contact 28 and/or part covers a portion of the corresponding exposed conductive wire 32 . The energy, transmitted quickly, heats device electrical contact 28 and conductive wire 32 , melting the end of contact 28 and causing it to be securely welded to conductive wire 32 , as shown in FIG. 7 . This procedure is repeated for each device electrical contact 28 . In an alternative preferred embodiment, each electrical contact 28 is micro-spot welded to conductive wire 32 . In this technique a microprobe touches and transmits electrical energy onto the free face of electrical contact 28 . As the system is grounded, this causes a large flow of electrical energy, which melts portions of contact 28 , welding it to conductive wire 32 .
[0028] FIG. 8 shows the connective portion of an alternative preferred embodiment of a stimulation paddle work piece in which device electrical contacts 28 ′ extend all the way across window 26 ′. The welding of device electrical contacts 28 ′ to the lead 30 ( FIG. 6 ) may be essentially identical to the welding of device electrical contacts 28 as described above. The preferred embodiment of FIG. 8 may afford a greater stability to device electrical contacts 28 ′, versus device electrical contacts 28 , as contacts 28 ′ are anchored on both sides of window 26 ′.
[0029] FIG. 9 shows an alternative preferred embodiment of a head 19 ′ with a polymeric coating 12 ′ on the back side of contact sites 28 ″, which are spaced further apart from each other. In one preferred method the polymeric coating 12 ′ is melted or ablated off by laser 16 ( FIG. 1 ) as contact sites 28 ″ are laser welded to a cable. The head 19 ″ of FIG. 10 is similar in concept to the head of FIG. 9 , but is adapted for the case in which the lead is arranged in a manner perpendicular to the cable.
[0030] A range of nervous system tissue compatible polymeric materials, sold under the trade designation Bionate® and sold in sheets that may be laminated together are available from Polymer Technology Group of Berkeley, Calif. Metal 14 ( FIG. 1 ) may be gold or a platinum-iridium alloy. First laser 16 may be a ND:YAG laser, which in one preferred embodiment is frequency multiplied, and second laser 16 ′ may be a frequency multiplied ND:YAG laser or a CO2 laser. Conductive wires 32 ( FIG. 6 ) may be made of an alloy that is referred to by the trade designation MP35N and is available from Fort Wayne Metals of Fort Wayne, Ind.
[0031] It shall be appreciated that these material selections are by way of example and any other suitable materials could be substituted without departing from the scope of the appended claims. Also, although some embodiments have been discussed in terms of SCS paddles, stimulation paddles for other indications can be fabricated according to other embodiments. For example, stimulation paddles can be fabricated according to some embodiments for cardiac stimulation, cortical stimulation, deep brain stimulation, peripheral nerve stimulation, gastric pacing, etc.
[0032] The above described methods of paddle fabrication are quite highly automated; thereby requiring far fewer manual operations compared with previously available production techniques for known stimulation paddles. This potentially lowers the costs of manufacturing and reduces the reject rate. Moreover, the process permits the creation of a set of paddles that are more precisely uniform to one another, thereby permitting a medical professional to have confidence that a particular paddle will not fail over time due to inaccurate fabrication processes.
[0033] The disclosed combination of physical dimensions and mechanical characteristics further enables SCS paddles to be inserted within the epidural space of a patient without performing a partial laminectomy. Specifically, by utilizing relatively thin layers of material, SCS paddles can be folded or otherwise deformed for placement within an insertion tool. The insertion tool can be inserted through spacing in the vertebral structures into the epidural space. The SCS paddle is then passed through the end of the insertion tool. The shape memory characteristic of the metal layer and, perhaps, the dielectric backing enables the SCS paddle to resume its original shape upon exiting the insertion tool thereby exposing the electrodes of the paddle to deliver the electrical stimulation.
[0034] Additionally, the physical dimensions and mechanical characteristics of the paddle reduce the probability of causing spinal cord compression. In some alternative embodiments, the paddle can also be made thick enough to be retained in place by the compressing force between the vertebrae and the spinal cord.
[0035] Skilled persons will appreciate that by using the above described method it is possible to create and connect an electrical probe having features that are on the order of 0.1 mm 2 in area without the risk of leaving trace amounts of photolithography agents on the probe. This is particular important in that nervous system tissue is highly sensitive and easily damaged by a wide range of compounds (even in very small concentrations).
[0036] Although representative embodiments and advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from this disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized without departing from the scope of the appended claims. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. | In one embodiment, a method of fabricating an implantable stimulation paddle comprises: providing a sheet of conductive material coupled to a first insulative layer; laser removing portions of the conductive material to form a pattern of conductive material, the pattern of conductive material including a plurality of isolated metal traces; providing a second insulative layer over the pattern of conductive material so that the pattern of conductive material is interposed between the first and second insulative layers; and exposing portions of the metal traces to form electrodes on the paddle for delivering electrical stimulation. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This application is based upon and claims benefit of U.S. Provisional Patent Application Ser. No. 61/703,330 entitled “SKYLIGHT ENERGY MANAGEMENT SYSTEM,” filed with the U.S. Patent and Trademark Office on Sep. 20, 2012 by the inventor herein, the specification of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
This invention relates to radiant energy management, and more particularly to controllers for use with systems for capturing solar energy to manage illumination and temperature within a defined space.
BACKGROUND OF THE INVENTION
Human thermal comfort is the function of both the air conditions (that is, temperature and air velocity) as well as the radiant environment of the occupants. Alternative types of heating systems, known as radiant heating systems, that use fluid circulated in the floors and/or walls of a building instead of forced hot air are common. Higher floor and/or wall temperatures provide a warm, radiant environment for the occupants which allows the same degree of comfort with a lowered air temperature. Each degree of setpoint temperature reduction can save 2 to 5% of the heat required for a building. In addition, the power required to circulate fluid through tubes in the floor is less than the power required to circulate warm air to deliver the same amount of heat. Further, the circulating air makes the occupant feel colder, negating some of the warming effect.
The most common method of radiant heating, via hydronic fluid circulation, has drawbacks. First, the necessary fluid lines must be embedded in the floor of the space, at significant expense. Retrofit applications of radiant heating are much more expensive, because retrofitting the tubes requires either replacement of the floor, or the addition of a new layer of concrete in which to embed the tubes, which adds further costs and construction complexities. Second, the thermal energy is delivered by conduction through the floor structure, and so the entire mass of the floor must be heated, leading to a large time lag between the initiation of heating from the system and the temperature rise of the floor—typically 30 minutes to one hour. This makes it impossible for the thermal control system to respond to many normal changes in the heating load or changes in the desired temperature of the room. Finally, common floor coverings and furnishings such as rugs, carpets, furniture and cabinets act as insulators to conduction of heat from the floor, which reduces the effectiveness of the heating and further increases the time lag in responding to changes in load and set point. Thus, there remains a need in the art for applications of radiant heating that avoid such disadvantages of previously known systems.
Further, skylight systems have been provided for illuminating a space below a skylight unit. However, there are a number of practical problems regarding the control of illumination levels with current skylight practices. For instance, most existing skylights have no active control elements at all. The control of illumination levels in the space is completely dependent on adjusting the levels of artificial illumination. Further, current skylight systems that use other modulation techniques such as shades or dampers also suffer drawbacks. For instance, modulation consists of reflecting or blocking the undesired levels of light. The excess light is either reflected back to the sky, which causes it to be wasted, or is absorbed by the modulating surface, which can overheat the skylight. Further, modulation by shades or dampers requires either movement of the shade surface by a significant fraction of the cross-section of the skylight area, or a large angle deflection of the dampers. Consequently, for practically sized motors and drive mechanisms, it is impossible to effect changes in the illumination levels in the time scale of less than one second. Still further, none of the existing systems that are known to the inventor herein are self-contained such that the skylight measures its own delivered illumination levels and adjusts its own dampers accordingly. Modulation of the lighting levels is performed by external systems tied into building system controls which increases system cost and complexity. Thus, there remains a need in the art for controlling the amount of illumination provided by skylight systems that may be more easily implemented than previously known systems.
SUMMARY OF THE INVENTION
A skylight module preferably including an energy management system that controls the amount of light allowed into an area is described. In one embodiment, the system comprises a louver assembly and a light sensor contained within a light well. The light sensor is in communication with a controller that manages the position of the louvers in the system and controls the amount of light allowed through the system.
In another embodiment, the system further comprises thermal sensors in communication with the controller, which allow for management of the louvers' position to maximize energy efficiency. The controller is configured to set the louvers' position so that the difference in temperature between the two thermal sensors is as small as possible.
In yet a further embodiment, the system comprises both the light sensor and the heat sensors and the controller is programmed to manage the position of the louvers to maximize light and energy efficiency. In one further embodiment, the system also comprises an occupancy sensor that allows the system to know whether a room is occupied in order to adjust the light requirements and louver positions of the system to maximize energy and light efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying drawings in which:
FIG. 1 is a perspective view of the system described herein.
FIG. 2 is a perspective view of two louvers in accordance with one embodiment of the present invention.
FIG. 3 is a close-up view of the energy conversion module in accordance with one embodiment of the present invention.
FIG. 3 a is a side view of a graphical representation of the energy conversion module in accordance with one embodiment of the present invention.
FIG. 4 is a side view of a thermal receiver in accordance with one embodiment of the present invention.
FIG. 5 is a perspective view of a thermal receiver in accordance with one embodiment of the present invention.
FIG. 6 is a graphical representation of the louver action as a fraction of incident energy and heat.
FIG. 7 is a representation of the trajectory of light reflected from one louver to another in one embodiment of the present invention.
FIG. 8 is an electrical diagram of the configuration of a heat sensor for controlling heat collection in accordance with one embodiment of the present invention.
FIG. 9 is a perspective view of an alternative configuration of heat sensors on the louver in accordance with another embodiment of the present invention.
FIG. 10 is a side view showing the reflection of light in an alternative configuration in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is of a particular embodiment of the invention, set out to enable one to practice an implementation of the invention, and is not intended to limit the preferred embodiment, but to serve as a particular example thereof. Those skilled in the art should appreciate that they may readily use the conception and specific embodiments disclosed as a basis for modifying or designing other methods and systems for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent assemblies do not depart from the spirit and scope of the invention in its broadest form.
Disclosed herein is a control system suitable for use with skylight assemblies, and particularly with skylight energy management systems as described in copending and co-owned U.S. patent application Ser. No. 13/749,053 titled “Skylight Energy Management System,” the specification of which is incorporated herein by reference in its entirety.
The system described herein can deliver radiant heating in the form of light from enhanced aperture skylights. The same heating from skylights that is undesirable in the cooling season can also be put to use in the heating season. One hundred footcandles of lighting provided as daylight is equivalent to 1 W per square foot of heating. The enhanced amount of lighting that is possible with the enhanced aperture modulated daylighting system set forth herein can deliver up to 300 footcandles of light on a bright winter day. This is enough to provide 50 to 100% of the daytime heating load. The heat is delivered at 100% efficiency, and it avoids the disadvantages described above with previously known systems. No modifications are required to the floor or wall structures, there is almost no time lag in the delivery of the heat, and radiant heat from above heats the upper surfaces of furnishings, as opposed to the lower surfaces, which enhances the radiant effect on the occupants. It also lowers the required air temperature in the building to provide the same level of comfort.
In addition to the positive effects of daylighting on productivity for the occupants of a commercial building space, heating with radiant light has additional specific benefits that are realized by the system set forth herein. The negative psychological consequences of the prolonged reduction of natural daylight during winter has been well documented. Seasonal affective disorder (SAD) is a medical condition that is caused by low natural lighting levels over a long period of time such as can occur in mid- to higher latitude regions in winter. Such conditions can be likely ameliorated by exposure to high levels of natural light such as can be achieved with the control system described herein.
A number of advancements are described herein relating to controls for an energy harvesting skylight. FIG. 1 shows a perspective view of an exemplary skylight module (shown generally at 100 ) which may incorporate the control system set forth herein. The skylight module 100 is configured for installation in, for instance, the roof of a building, such as a commercial building. The module is configured to provide approximately 50-70 percent more daylighting than standard daylighting solutions, as well as generating thermal heat at temperatures of up to 300 F. This is accomplished by providing a higher skylight to floor ratio (SFR) than typical skylight installations. The larger aperture is used to provide full interior illumination during cloudy, morning and afternoon periods. The solar energy that is in excess of that required for illumination is captured by a single axis micro-concentrating collector embedded in the skylight, making the energy available to offset building thermal loads while relieving the building cooling system of the solar heat load that would be coming through such a large roof opening.
The louvers 200 of a module include a thermal receiver 300 ( FIG. 2 ) on the back of the louvers that is preferably relatively small in size, such that it is possible to have a high degree of focus of the mirror system. A small thermal receiver (as described herein) has a proportionally reduced heat dissipation rate for the same heat input, and thus increases the efficiency of the thermal collection, and consequently increases the peak collection temperatures up to about 220 F. The heat collected from such assembly may be put to various uses, including service water heating, space heating, and some process heat applications including driving single effect absorption chillers for air conditioning.
With particular regard to the skylight energy management system shown in FIG. 1 , the system provides the means to seamlessly vary the amount of lighting delivered by each skylight module 100 in real time, with the balance of the solar energy not going into daylighting being captured in the form of thermal heat. Moreover, and again with particular regard to the system shown in FIGS. 1 and 2 , louvers 200 may be provided with a thermal receiver 300 that increases the collection temperature to the range of 275 F to 300 F, thus providing more high-value applications of the heat, such as double effect chillers with up to double the cooling value per unit of heat input, and also power generation using organic Rankine cycle or Kalina cycle turbine/generator systems. Alternatively, improving the collection efficiency in the 200-220 F range greatly improves the economics of thermal process heat applications such as single effect chillers. The system shown in FIG. 1 incorporates improved optics which provides a concentration ratio of 10 to 15, resulting in a smaller thermal receiver area and temperatures high enough to drive these higher value loads, and greater efficiency at lower temperatures. Being able to drive loads that provide efficient cooling and power generation vastly expands the number of applications for the system, because many more buildings have need for cooling and power than more application-specific process heat uses.
With reference to FIGS. 1-3 , the monitor 116 (skylight) provides 1) structural support to the energy conversion module/louver assembly 220 (ECM), 2) thermal insulation between inside air and the outside, and 3) direction and diffusion for the light from the sky into the space below. The ECM 220 , mounted on the south face of the monitor 116 (assuming the south face is facing the sun), is a micro-concentrating thermal collector and light managing device. A controller board 130 and a small electric stepper motor 132 control the angle of the louvers 200 to deliver the desired amount of light through the ECM 220 , while converting the excess light to high grade thermal heat. Fluid lines 134 circulate coolant directly through each louver 200 to pipes located on the roof or in the ceiling space below the skylight modules 100 .
The louvers 200 are moved by stepper motor 132 and linkage 136 which is located on, for example, the west end of the ECM 220 . The controller board 130 is preferably connected to a central control unit and sends commands to the stepper motor 132 which is connected to an actuation bar 137 of linkage 136 . The actuation bar 137 is joined to each louver 200 by link arms 138 that connect preferably to the last inch of the west end of the louver 200 . The action of the linkage is shown in the schematic views of FIG. 3A with a cross section of four louvers. The actuation bar 137 moves left to right with a small vertical component as the link arms 138 swing in a circular motion as the louver 200 pivots around a slot pivot 202 on the back of each receiver tube. In an exemplary embodiment of the invention, the receiver tubes do not articulate. This allows for fixed fluid connections to the fluid lines 134 that connect the thermal receivers, an improvement from prior designs that required dynamic fluid seals between the receiver tubes and the fixed fluid tubes.
FIG. 2 shows cross sections of two louver sections to show additional detail. The mirror 204 of louver 200 can be either continuously curved or have a faceted shape. The facets are much easier to fabricate with simple sheet bending equipment; the continuously curved design requires custom tooling and high-force hydraulic presses to fabricate. The radius of curvature of the mirror 204 varies along its length to optimize the focusing of light on the thermal receiver 300 and secondary reflecting surfaces (described in greater detail below). The portion of the mirror 204 near the top is generally farther away from the adjacent receiver/reflector surfaces and so requires a larger radius of curvature (less curved shape). The portion of the mirror 204 near the bottom is generally presented with a shorter distance to the adjacent receiver and so requires a smaller radius of curvature to focus the light. In an exemplary embodiment of the invention, the mirror 204 is attached to a pivot bar 206 that runs the length of the mirror 204 (or alternatively may consist of short sections to reduce thermal conductivity and losses). The pivot bar 206 has a linear bulb that fits into a slot 208 on the back of the receiver tube 300 to provide a pivot point for rotation. It is important to minimize the thermal conductivity between the hot receiver tube 300 and the mirrors 204 to keep the mirrors 204 from becoming cooling fins. Therefore, the pivot bar 206 is preferably attached to the mirror 204 with silicone foam tape which has a low thermal conductivity but can withstand the high temperatures of the thermal receiver 300 . In addition, the outer surface of the linear bulb may be coated with Teflon or other high-temperature insulating plastic to minimize thermal conduction from the thermal receiver tube 300 to the pivot bar 206 .
As best shown in FIG. 2 , and again in accordance with an exemplary embodiment of the invention, also attached to the pivot bar 206 is the reflecting diffuser 222 . The reflecting diffuser 222 directs the rays of sunlight that strike it into the space below. The reflecting diffuser 222 (as well as the secondary mirror on the thermal receiver tube 300 , discussed below) is made of specialty lighting reflector sheet that is partially specular and partially diffuse. Such specialty lighting reflector sheet material is readily commercially available, and may comprise, by way of non-limiting example, ALANOD 610G3 available from ALANOD GMBH & CO. KG, or ACA 420AE/DG available from ALUMINUM COIL ANODIZING CORP. The material reflects incoming light rays into a 20 degree cone which provides more diffuse projection into the space below while maintaining the directionality of the light. A purely diffuse reflector, such as a white painted surface, while providing soft light to the space below, would waste light by reflecting some of it back towards the primary mirror. A purely specular reflector, such as a polished reflector, would direct all of the light efficiently into the space, but would require secondary conditioning to avoid harsh glare spots. The shape of the reflecting diffuser 222 can either be curved, as shown in FIG. 2 , or straight. The main criteria in configuring the reflecting diffuser 222 is that the reflecting diffuser intercept preferably all light rays that come from the primary mirror 204 at the shallow angle so that they do not get re-reflected back to the primary mirror 204 and lost.
The details of the thermal receiver tube 300 in accordance with such exemplary embodiment are displayed in the cross-sectional views of FIGS. 4 and 5 . The main body of the thermal receiver 300 is preferably formed of extruded aluminum. To the base extrusion, three features are attached using high-temperature epoxy adhesives: a thermal baffle 302 , a thermal collector 304 , and a secondary mirror 306 . The operation and further details of such assembly are set forth in full in U.S. Patent Application Publication No. US2013/0199515, and are thus not discussed further here.
Light exiting from the bottom of the skylight module 100 is sensed using low-cost light sensors that feedback into the controller board 130 mounted in each skylight module 100 . The optics are designed such that at every sun angle, the amount of light that comes through the energy conversion assembly 220 is a monotonic function of the angle of louvers 200 . That is, moving the louvers 200 at an angle more open to the sky always increases the amount of light coming through, and moving the louvers 200 to an angle more closed to the sky always reduces the amount of light coming through. Therefore, a simple proportional integral control loop can be employed by controller board 130 to keep the light levels at a desired set point. Secondly, the excess light is captured for useful thermal energy. Finally, and with reference to the chart of solar energy allocation versus louver angle depicted in FIG. 6 , because of the degree of concentration of the optics, the fraction of incident direct solar energy that is converted into illumination goes from 0 to 100% in a louver deflection of less than 3°. This very small deflection can be executed in less than one second, such that the bandwidth of the lighting control can be faster than the disturbances, such as varying sunlight levels. Because of this, the skylight optics combined with a moderately sized motor 132 and electronics processing power of controller board 130 can maintain a very precisely controlled and constant amount of illumination into the space below.
This precise control of illumination coming from the skylight module 100 can be used to effect a number of efficiencies and functional enhancements. For instance, in many retail environments such as grocery stores, illumination levels are precisely controlled in order to present merchandise in the best light. Different kinds of merchandise such as produce or dry goods are presented at different lighting levels which have been found to produce optimal sales results. By using skylight modules 100 to maintain a precisely controlled illumination level throughout the day even under varying sky conditions, the inventive energy managing skylight described herein can provide these precise lighting levels with no artificial illumination. It is even possible to vary these control lighting levels as a function of the time of day. For interior spaces that are only intermittently occupied, it is possible to place an occupancy sensor at the base of each skylight module 100 . When the sensor does not detect the presence of occupants, it can be programmed to deliver no illumination and maximize the amount of thermal heat collected. When the sensor detects an occupant, the lighting levels can be raised to the required illumination level faster than the time it takes for many commercial lighting fixtures to turn on.
Because each skylight module 100 has its own intelligent controller board 130 , it is a very low cost option (e.g., $20) to add a wireless communication module that can directly control the light fixtures in the vicinity of the module that have a similar low-cost (e.g., $50) wireless receiver. The lighting controls can either be on/off, or modulating which provides a continuously dimmable output of the associated lighting fixtures. This has a number of advantages compared to the current state-of-the-art. Current state-of-the-art in automatic daylight harvesting systems for flat roof commercial buildings is to install an array of sensors 5 to 10 feet above the floor of the space. The sensors measure the total illumination reaching the floor from both the skylights and the artificial lighting. This information is fed back to a central controller, and the artificial lighting is either turned on or off or dimmed to reach the desired setpoint. Combining the control logic for both the skylight module 100 and the artificial light illumination levels in the skylight module 100 itself has several advantages. First, for periods of time when the skylight modules 100 are providing more than the desired lighting levels, the controller can attenuate the amount of light coming from the skylight module 100 . Second, because the skylight module 100 has a knowledge of the amount of light that it is putting out, the array of sensors near the floor of the space is unnecessary. Finally, there are a number of factors that can confuse a floor illumination sensor. The sensor is generally incapable of distinguishing light which is coming from the skylights, the artificial lights, or reflected light. Objects which pass temporarily through the field of view of the sensor which might for example reflect additional light onto the sensor would cause the lighting in that zone to be dimmed unnecessarily, causing a dark zone. The light sensors employed in the system described herein are in the light well of the skylight, and are thus not susceptible to such disturbances. The “light well” is the space that exists between the bottom plane of the skylight module 100 and the open area at the bottom of the roof curb to which the skylight module 100 is attached for mounting to a roof.
When the system controller is calling for very low or zero illumination levels, the controller cannot use light sensors as feedback to determine the optimal louver position. FIG. 7 shows the light path for a louver 200 that is delivering 100% heat and no illumination. It is desired that all of the incoming light be projected onto the two thermal absorbing surfaces. Previous versions of the energy managing skylight product used open loop control in which the optimal angle was calculated based on time of day location and orientation of the module. While conceptually a low-cost approach, a significant amount of programming is required to set up the tables which determine the optimal angles for each installation. A system that uses purely feedback control requires little or no upfront programming and is more robust in the presence of disturbances in the field.
In general, it is difficult for a control loop designed to maximize the controlled variable to use the controlled variable directly as feedback because when the system is actually producing at its maximum value, there is no error signal to feedback to the controller. It is necessary to “dither” the signal by intentionally introducing disturbances by perturbing the system from its optimal setting. In systems with a significant amount of time lag between errors in input and output, this dithering technique is difficult to employ. The significant thermal mass of the receiver does produce a significant time lag between the presence of errors in pointing and changes in the temperature of the tube. Also, an issue is the fact that the temperature of the tube is also a function of the temperature of the fluid going through it. Changes in the incoming fluid temperature due to changes in other parts of the system could therefore confuse a feedback controller based on the receiver to temperature.
For these reasons, it is preferred to measure and minimize the “spilled” or lost energy, not the captured energy. One approach to measuring the spilled energy is to directly measure the light using a light sensor near the receiver tube. A sensor that measures the amount of concentrated light falling onto the surface would be difficult to use because the focused light is concentrated by a factor of 10 to 15 and saturation or overheating of the light sensor is hard to avoid.
Thus, an approach using two temperature sensors to control thermal heat collection, which addresses all of these issues, is shown in FIG. 7 . Two temperature sensors 402 and 404 are mounted on a sensor bracket 406 which is attached to one of the receiver tubes 300 (because all of the mirrors move in concert, it is only necessary to instrument one of the tubes). The sensor bracket 406 is placed in such a position that is completely shadowed by the adjacent mirror so that no direct sunlight strikes the bracket. The sensor bracket is made of a thin metal sheet which is thermally isolated from the receiver tube 300 upon which it is mounted. The thermal insulation 408 is important to decouple the temperature sensors 402 and 404 from both the thermal lag of the receiver tube 300 to, and the temperature disturbances coming from, the fluid itself. The face of the sensor bracket 406 that faces the concentrated light is painted a medium gray color with a light absorbance factor of about 0.3. If the mirror 204 is perfectly focused and all of the light is falling on the receiver tube 300 , the temperature of the upper and lower temperature sensors 402 and 404 will be equal. As the sun moves across the sky or something else causes an error in the pointing, some of the concentrated light will either spill high or low from the receiver tube 300 . The light that then strikes either the upper or lower region of the bracket 406 will cause a differential heating of the bracket 406 in that area. If the bracket 406 is sufficiently thin, there will be a negligible amount of heat conduction between the two ends of the bracket 406 . Temperature sensors 402 and 404 mounted on the opposite side of the bracket 406 will then measure this differential in temperature and generate a signal to the controller proportional to the difference in temperature in a direction which drives the temperature differential to zero. The sensor that is receiving no stray light will be at the ambient temperature inside the skylight module 100 . The other sensor, which is receiving stray light, will be at a temperature that is proportional to the amount of light striking it and the optical reflectivity of the bracket 406 . Therefore, the temperature that the sensors reach, and therefore the gain of the controller, can be controlled by essentially the color of the bracket 406 . Because the controller only looks at the temperature difference between the two sensors 402 and 404 , and not the absolute temperature, it is insensitive to common mode disturbances such as ambient temperature variations. To compensate for errors in the calibration of each sensor 402 and 404 , the temperature of the two sensors can be sampled at nighttime when there is no solar energy present to drive a temperature difference. The static temperature difference between the two sensors 402 and 404 can then be taken out of the calculation for feedback control.
An alternative sensor configuration for controlling thermal heat collection is shown in FIG. 8 . A possible drawback of using temperature sensors to determine the position of the light beam is the time lag between the impingement of the light on the absorber and the increase in temperature sensor. An alternative approach is to use a sensor 410 ( FIG. 8 ) that measures the light beam directly. The concentration of the light striking the thermal absorber and consequently the spillover light sensor can be as high as 7 to 10 times ordinary sunlight. Light sensors to measure this level of flux are not commercially available. A light sensor 410 as shown in FIG. 8 is able to operate in the extreme temperature and illumination environment required for this sensor.
With continued reference to FIG. 8 , a photovoltaic cell 412 is mounted on a small circuit board 414 with a shunt resistor 416 . The shunt resistor 416 dissipates the power generated by the PV cell 412 , and the voltage across the resistor 416 is directly proportional to the total light energy striking the sensor 410 over a wide range. Two sensors 410 can be put in series to accurately determine the total light flux high or low of the thermal absorber 304 . Silicone based photovoltaic cells are able to withstand temperatures as high as 180° F. and so are most suitable for this application. As shown in FIGS. 9 and 10 , the two sensors 410 in series may be attached to a bracket 418 that in turn is attached to receiver tube 300 , reaching above and below the thermal absorber 304 , can thus provide immediate and accurate feedback to the controller for any louver and sun position ( FIG. 10 showing the impact of various sun angles on an array of sensors 410 ).
Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It should be understood, therefore, that the invention may be practiced otherwise than as specifically set forth herein. | A controller for an energy management system that controls the amount of light allowed into an area is provided. The system comprises a louver assembly and a light sensor contained within a light well. The light sensor is in communication with a controller that manages the position of the louvers in the system and controls the amount of light allowed through the system. The system further comprises thermal sensors in communication with the controller, which allow for management of the louvers' position to maximize energy efficiency. | 4 |
BACKGROUND
The present invention generally relates to the area of luggage options for motorcycles. Specifically, this invention relates to luggage which may readily be fastened to a motorcycle, the luggage having internal shelves, thus providing ease, convenience, and organization for the rider and/or passenger in transporting their belongings by motorcycle.
Limited space is available on motorcycles for a rider and the rider's passenger to carry their belongings. Some motorcycles may come equipped with large capacity saddlebags or panniers hanging down on either side of the rear wheel, as shown in U.S. Pat. No. 4,442,960 (Vetter). However, such luggage can be expensive, difficult to remove from the motorcycle, and too bulky to easily hand carry when the rider wishes to carry his or her belongings into a motel, campsite or other lodging. Moreover, some motorcycle riders feel such luggage is unsightly on their motorcycles and creates additional surface area for wind resistance.
Because of the disadvantages of mounting motorcycle luggage on either side of the wheel, U.S. Pat. No. 5,405,068 (Lovett) proposes a bag supported by either the motorcycle seat member or by a rack structure. An object of the bag in the '068 patent is to overcome the disadvantages of the saddlebags or panniers by providing a travel bag which can be easily attached and removed from the motorcycle. This bag is secured to the motorcycle through the use of a pocket on the front of the bag, where the pocket is sized to fit snugly over the rear passenger seat back or sissy bar. The pocket is located on the bag so that the bottom of the bag will just rest on the luggage rack when the seat back is completely inserted into the pocket. However, careful construction of the pocket is central to the successful operation of this bag. The pocket must be so constructed that the internal volume of the pocket is less than this bag. The pocket must be so constructed that the internal volume of the pocket is less than the volume of the padded seat back, because the pocket must partially compress the resilient material of the seat back for the bag to be securely attached to the motorcycle. Because the rear seat back varies in dimensions from model to model of motorcycle, it is necessary to specifically size the pocket and the rest of the bag for each particular model of motorcycle.
Another disadvantage of fabric bags, which have no internal reinforcement members, is that the bag must be completely filled, because a loosely filled bag will vibrate and flap when the motorcycle is in motion. The bag disclosed in the '0068 patent partially solves this problem through the use of a zippered gusset that allows the travel bag to expand as extra space is required. However, depending upon the volume of items to be stored in the bag, if the bag disclosed in the '0068 patent is only partially filled, with the zippered gusset closed, excess fabric may still vibrate and flap.
A feature common to most previous motorcycle luggage, including saddlebags, panniers, and the bag disclosed by the '0068 patent, is that the main storage space defined by each of these devices is merely a large enclosure with minimal internal structure for organizing the user's belongings. The user fills the enclosure with his or her belongings from the bottom of the luggage device until the luggage is fully loaded. However, because there is no internal structure, items packed within the enclosure may shift during travel, with smaller or heavier items working to the bottom of the enclosure. Although the user, desiring to have ready access to certain items, may pack these items at the top of the enclosure, it may be necessary to completely empty the bag in order to locate the items because they may have shifted to the bottom of the enclosure during travel.
The lack of internal storage structure in existing motorcycle luggage also results in clothing items becoming crumpled and wrinkled from shifting of the packed items. Clothing items which were neatly pressed when placed within the luggage become wrinkled because there is no internal structure for supporting and protecting clothing from being crumpled inside the luggage.
SUMMARY OF THE INVENTION
The present invention is a travel bag adaptable for motorcycle transportation. The invention is comprised of a shell, a shelving insert contained within the shell, and securing members for securing the travel bag to a motorcycle. The shell is opened by operating fasteners allowing access to the shelving insert and the inside of the shell. The shelving insert has a top shelf, bottom shelf, two side pieces and a plurality of intermediate shelves, and may have a back piece. The travel bag provides a convenient and secure apparatus for organizing, storing and transporting clothing, helmets, gloves, toiletries, shoes, camping equipment, tools and other items on the back of a motorcycle. Items may be stored on the shelves of the shelving insert or in various pockets which may be attached to the exterior of the shell. The travel bag maintains the organization of the goods packed by the user, allowing the user ready access to specific desired items without the user having to unpack all of the contents of the bag. This invention allows the user to pack and transport neatly pressed clothing items, without the clothing items becoming excessively wrinkled or disorganized. This invention provides internal reinforcement to a fabric travel bag so that a partially-filled travel bag will not vibrate or flap excessively when the motorcycle is in motion. This bag may be secured to the motorcycle without the need to size the mechanism for the particular model of motorcycle. Rollers or wheels may be mounted on the bottom of the travel bag allowing for easy transportation of the device after it has been removed from the motorcycle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an isometric view of the subject invention.
FIG. 2 shows a side elevational view of the subject invention mounted on the luggage rack of a motorcycle.
FIG. 3 shows a side elevational view of the subject invention mounted on the passenger seat-of a motorcycle.
FIG. 4 shows an elevational view of the left side of the subject invention.
FIG. 5 shows a rear elevational view of the subject invention.
FIG. 6 shows a front elevational view of the subject invention, with the flap unfastened, showing how a helmet or other bulky items may be stored.
FIG. 7 shows a front elevational view of the subject invention, showing how the shell may be opened from either the top or the bottom.
FIG. 8 shows a top view of the subject invention.
FIG. 9 shows a bottom view of the subject invention.
FIG. 10 shows an isometric view of an alternative embodiment of the subject invention.
FIG. 11 shows a left side elevational view of an alternative embodiment of the subject invention.
FIG. 12 shows a front elevational view of an alternative embodiment with the flap unfastened.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention comprises a travel bag with shelving insert adaptable for motorcycle transportation. The invention is comprised of two major components, the first component being a heavyweight fabric shell 10 , which may be constructed of a durable, water-resistant, and flexible material, such as CORDURA. The shell 10 provides an enclosure for the second major component, a shelving insert 38 . The shelving insert 38 may be constructed of lightweight rigid materials, such as plastic, aluminum, fiberglass, wood and/or composite materials.
Although other shapes are possible, in one embodiment the fabric shell 10 is comprised of a top surface 12 , a bottom surface 14 , a rear surface 16 , a front surface 18 , and two side surfaces 20 , which are joined together in approximately a rectangular prism. Access to the inside of the fabric shell is allowed by activating shell fasteners 36 which may be installed at the seam 32 joining the front surface 18 to the side surfaces 20 . When the shell fasteners 36 are opened, a flap 34 is formed, such as shown in FIG. 6 . As shown in FIG. 7, access to particular portions of the shelving insert 38 is allowed while leaving the flap 34 closed over other portions of the shelving insert to protect items from rain or moisture.
Additional components of the fabric shell 10 of the travel bag are security flaps 24 , attached to the rear surface 16 , mounting straps 52 , and corresponding quick clip connectors 54 . A handle strap 56 , mounted rollers 58 and side pockets 62 may also be attached to the fabric shell 10 .
The shelving insert 38 is comprised of a top shelf 42 , bottom shelf 44 , side pieces 48 , and intermediate shelves 50 . A back piece 46 may be connected to the back edges of the top shelf 42 , bottom shelf 44 , side pieces 48 and intermediate shelves 50 . The shelving insert 38 may be held within the fabric shell 10 by various insert fasteners 40 such as screws, adhesives, tacks, or hook and loop fasteners, sold under the registered trademark, “Velcro.” If used, hook and loop fasteners may be attached to the inside surfaces of the shell 10 by various means, such as sewing or adhesives. A corresponding hook and loop fastener is attached to the outside surfaces of the shelving insert 38 .
Different means may be used for securing the travel bag to the motorcycle. The travel bag may be attached to the motorcycle with security flaps 24 attached to the rear surface 16 of the bag, which wrap around the rear passenger seat back 28 of the motorcycle. Hook and loop fasteners 26 are attached to the security flaps 24 in such a manner as to allow the security flap on one side of the rear surface 16 to fasten to the corresponding security flap of the opposite side of the rear surface. With the bottom surface 14 of the travel bag resting on the motorcycle luggage rack 22 , as depicted in FIG. 2, the security flaps 24 from each side of the rear surface 16 are wrapped tightly around the rear passenger seat back 28 . Unlike pocket devices which must be specifically sized for the dimensions of the specific rear seat back, the security flaps 24 of the present invention are readily adaptable to rear seat backs and sissy bars of different dimensions, by simply adjusting the relative positions of each flap by adjusting the hook and loop fasteners 26 on each security flap.
Another means of securing the travel bag to the motorcycle is with mounting straps 52 and respective quick clip connectors 54 attached to the bottom surface 14 and/or lower sections of the rear surface 16 or front surface 18 of the travel bag. The mounting straps 52 , preferably nylon, are wrapped tightly around members of the motorcycle luggage rack 22 , with the ends of the mounting straps being secured into the receiving ends of the quick clip connectors 54 . Both the security flaps 24 and the mounting straps 52 should be used to secure the travel bag to retain the bag firmly in place during travel.
When the travel bag is attached to the motorcycle as depicted in FIG. 2, it has the added benefit of providing additional back support for the rear passenger on the motorcycle. An alternative method of attaching the travel bag is available where only one person is on the motorcycle. The bottom surface 14 of the travel bag may be rested upon the rear passenger seat 30 , so that the security flaps 24 are facing toward the rear of the motorcycle as depicted in FIG. 3 . Mounting the travel bag in the manner depicted in FIG. 3 provides additional back support for a single person riding the motorcycle. To mount the travel bag to the motorcycle in this manner, the bag is simply turned around so that the rear surface 16 and the security flaps 24 are oriented to face the rear of the motorcycle, toward the rear passenger seat back 28 . The mounting straps 52 may then be looped around portions of the motorcycle, such as passenger handrail, with the ends of the mounting straps being secured into the receiving ends of the quick clip connectors 54 .
In one embodiment, the travel bag has rollers 58 mounted to either the bottom surface 14 , or mounted to the edge of the rear surface 16 adjacent to the bottom surface. The rollers 58 allow the user to roll the bag on the ground after the bag has been dismounted from the motorcycle. The back piece of the shelving insert 46 or and/or the bottom shelf of the shelving insert 44 provide hard surfaces to which the rollers 58 might be attached through the fabric shell 10 by fasteners, such as screws, nails, rivets, or bolts. As an alternative, the rollers 58 may be attached directly to the fabric shell 10 . A handle strap 56 for either lifting the travel bag or pulling the bag along on the rollers 58 is attached to either the top surface 12 or the rear surface 16 of the fabric shell 10 . Side pockets 62 may be attached to the side surfaces 20 to provide additional storage capacity for the user, which may be sized and located for convenience and the configuration of the particular motorcycle.
In one embodiment of the travel bag, additional storage volume is provided by increasing the height dimension of the fabric shell 10 so that the volume between the top surface of the fabric shell 10 and the top shelf 42 of the shelving insert 38 is sufficiently enlarged to allow for the storage of larger items inside the travel bag, resting on the top shelf. For example, as depicted in FIG. 6, this space may be used for storage of motorcycle helmets 60 . When this storage volume is not required, the excess fabric may be folded over against the top self of the shelving insert 42 and secured by the top straps 64 to prevent the extra fabric from vibrating or flapping during operation of the motorcycle.
In another embodiment of the travel bag, shown in FIGS. 10 through 12, the top surface 12 ′ fits tightly over the top shelf 42 ′ of the shelving insert 38 ′, so there is no available storage volume above the top shelf. Although this embodiment has less storage capacity, the travel bag has a streamlined appearance which may be preferred by some users. This embodiment shares the same features as the first embodiment, such as security flaps 24 ′ attached to the rear surface 16 ′, a front surface 18 ′, and two side surfaces 20 ′, which are joined together in approximately a rectangular prism. Access to the inside of the shell is allowed by opening shell fastener 36 ′ which may be located at the seam 32 ′. Flap 34 ′ is formed when shell fastener 36 ′ is opened.
The shelving insert 38 ′ of this embodiment is comprised of a top shelf 42 ′, bottom shelf 44 ′, side pieces 48 ′, and intermediate shelves 50 ′. A back piece 46 ′ may be connected to the back edges of the top shelf 42 ′, bottom shelf 44 ′, side pieces 48 ′ and intermediate shelves 50 ′. The shelving insert 38 ′ may be held within the fabric shell 10 ′ by various insert fasteners 40 ′ such as screws, adhesives, tacks, or hook and loop fasteners. If used, hook and loop fasteners may be attached to the inside surfaces of the shell 10 ′ by various means, such as sewing or adhesives. A corresponding hook and loop fastener is attached to the outside surfaces of the shelving insert 38 ′. Other features of this embodiment are similar to those of the embodiment disclosed in FIGS. 1 through 9.
Use of all of the embodiments of the travel bag is simple. With reference to the embodiment disclosed in FIGS. 1 through 9, the user opens the fabric shell 10 by activating shell fasteners 36 , and place his or her clothing and belongings on the intermediate shelves 50 and the bottom shelf 44 of the shelving insert 38 . For this embodiment, items may also be placed on the top shelf 42 . The shell fasteners 36 are activated to close the fabric shell 10 . Additional items may be stored inside the side pockets 62 . Using the handle strap 56 , the user may pull the bag on its rollers 58 to the motorcycle. Lifting the travel bag by the handle strap 56 , the user places the bottom surface 14 on the motorcycle luggage rack 22 or the rear passenger seat 30 . The mounting straps 52 are run beneath the members of the luggage rack 22 and latched into the quick clip connectors 54 , and the ends of the mounting straps pulled to tighten any slack. The security flaps 24 are wrapped around the rear passenger seat back 28 and connected to their opposite member by hook and loop fasteners 26 . Any loose straps should be secured to prevent flapping. The user may then proceed with his or her motorcycle travel, and, upon arriving at the user's destination, perform the above steps in opposite order to remove the travel bag and unload the user's belongings.
Although the subject invention has been described and illustrated in detail, those skilled in the art appreciate that various adaptions and modifications of the preferred embodiments can be configured without departing from the spirit and scope of thee invention. Thus the scope of the invention should not be limited by the specific structures disclosed. Instead the true scope of the invention should be determined by the following claims. | A motorcycle travel bag comprising a shell and a shelving insert, wherein the shelving insert provides a convenient and secure apparatus for organizing, storing and transporting various items on a motorcycle. Items may be stored on the shelves of the shelving insert or in various pockets which may be attached to the exterior of the shell. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to no-carbon copying paper, more particularly to improvements in no-carbon copying paper produced by combining microcapsules containing a colorless electron-donative organic compound with activated clay which is an adsorbent material capable of adsorbing said organic compound to develop color.
2. Description of the Prior Art
No-carbon copying paper is well known, and, for example, those disclosed in U.S. Pat. Nos. 2,712,507, 2,800,457 and 2,730,457 are produced by combining microcapsules containing a colorless electron-donative organic compound (hereinafter referred to as "color former") with an electron-attractive adsorbent material (hereinafter referred to as "color developer") which adsorbs said color former to develop color.
No-carbon copying paper is composed of a sheet (called "top sheet") produced by providing a support with a layer of microcapsules containing a color former, a sheet ("under sheet") produced by providing a support with a color developer layer and, if necessary, one or more sheets ("intermediate sheets") inserted between top sheet and under sheet, which intermediate sheets are produced by providing the right side of a support with a color developer layer and its back side with the above-mentioned microcapsule layer. The term "color developer sheet" hereinafter used refers to both above-mentioned under sheet and intermediate sheet.
Microencapsulation has heretofore been carried out by a coacervation method, an interfacial polymerization method, an in situ method, or the like, and as the color former, there are used malachite green lactone, crystal violet lactone, benzoyl leucomethylene blue, rhodamine B lactam, 3-dialkylamino-7-dialkylamylfluoran, 3-metyl-2,2-spirabi (benzo-[f]-chromene), and the like. As the color developer, there are generally used, for example, solid acids such as acid clay, activated clay, attapulgite, zeolite, bentonite, and the like; phenol resins such as p-tert-butylphenol resin, p-phenylphenol resin, p-octylphenol resin, and the like; organic compounds such as succinic acid, tannic acid, malonic acid, maleic acid, gallic acid, and the like; and aromatic carboxylic acids such as benzoic acid, salicylic acid, substituted salicylic acids, naphthoic acid, diphenic acid, and the like and metallic compounds thereof.
Among these color developers, those practically used from a consideration of their characteristics are activated clay, phenol resins and substituted salicylic acids (or their salts).
Among these color developers, organic color developers such as phenol resins, substituted salicylic acids, and the like are disadvantageous in that they tend to be decomposed by sunlight to change color to yellow and in that the colored characters have so poor solvent resistance that they are defaced. On the other hand, the solid acids as inorganic color developers are free from these disadvantages and can improve the shelf life of the coated paper. Activated clay used as the color developer is prepared by treating acid clay or analogous clay with a mineral acid to dissolve the acid-soluble basic components such as alumina, iron, and the like, and thereby adjusting its surface area to 200 m 2 /g or more, as described in Japanese Patent Publications Nos. 2,373/1966, 7,622/1966, 8,811/1967. etc. Activated clay is amorphous from X-ray observation, has a large surface area, and is very different in properties from pigments for coating ordinary paper.
Kaolin, a representative clay for coating paper, shows fluidity when dispersed in water up to a concentration of 70% or higher. On the other hand, activated clay becomes highly viscous and loses fluidity to gel at a concentration of about 45%. At present it is desired from a viewpoint of productivity and economy in energy to apply a clay for coating paper in the form of a highly concentrated coating color. However a highly concentrated coating color of activated clay is very difficult to prepare for the reasons mentioned above, and therefore, in the existing circumstances, there is mainly employed an air knife coater method using a coating color of a low concentration.
When kaolin and activated clay were individually added in an equal amount to starch and latex and each of the resulting mixtures was applied to paper, after which the surface strength and the stains on the blanket at the time of printing were measured, there were obtained such results that in the case of using kaolin, much higher surface strength and less stain on the blanket were brought about than in the case of using activated clay. When the adhesive is further added to activated clay, the surface strength is improved and the stains on the blanket is reduced a little. However the depth of developed color is decreased so that the aptitude as a color developer sheet for no-carbon copying paper is lost.
SUMMARY OF THE INVENTION
An object of this invention is to lower the viscosity of activated clay-containing coating color for a color developer sheet used in no-carbon copying paper to improve its fluidity and thereby make it possible to apply it at a high concentration.
Another object of this invention is to maintain the surface strength of a color developer sheet, prevent stains on the blanket at the time of printing, prevent the lowering of the colored characters, obtain excellent sunlight resistance of the colored characters, and keep the aptitude for pasting.
The above-mentioned objects of this invention have been accomplished by no-carbon copying paper composed fundamentally of a color former sheet produced by coating a support with microcapsules containing a colorless electron-donative organic compound as a color former and a color developer sheet produced by coating a support with a coating color containing activated clay as a color developer which adsorbs the aforesaid electron-donative organic compound to develop color, wherein the aforesaid activated clay-containing coating color is prepared by adding polyvinyl alcohol, styrene-butadiene latex and a wax emulsion to activated clay.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 are rheological diagrams of the coating color in Examples 1 and 2 of this invention, respectively, and
FIGS. 3, 4 and 5 are rheological diagrams of coating color in Comparative Examples 1, 2 and 3, respectively.
DETAILED DESCRIPTION OF THE INVENTION
According to this invention, there were added a polyvinyl alochol and a styrene-butadiene latex both of which are used as dispersants and adhesives as well as a wax emulsion which is used as an additive to activated clay to obtain a coating color for a color developer sheet, which coating color is then applied to a support such as paper or the like to obtain a color developer sheet.
According to this invention, activated clay shows greatly improved dispersiveness in water and fluidity, and it becomes possible to lower the viscosity of the coating color, that is, to apply the coating color at a high concentration. Moreover, the applied amount becomes easy to control and hence coating workability has been improved. At the same time, energy saving has been practiced and productivity has been improved.
It has become apparent that the color developer sheet obtained maintains high surface strength, is free from stains on the blanket at the time of printing, shows no lowering of the depth of developed color, and gives excellent effects on the sunlight resistance of colored characters and on the aptitude for pasting.
The activated clay used in this invention is generally prepared by treating acid clay with an acid, washing it with water, drying and pulverizing it.
As the polyvinyl alcohol, there are preferably used those having a saponification degree of 88 mole % or more and a polymerization degree of 500 or more.
As the styrene-butadiene latex, there are preferably used those containing 55.0 to 65.0% by weight of styrene as the main component.
When the amount of styrene is higher than 65.0% by weight or lower than 55.0% by weight, the coated paper is low in water resistance, so that it becomes poor in aptitude for printing.
The objects of this invention can also be accomplished by using, as the styrene-butadiene latex used in this invention, a carboxyl-modified styrene-butadiene latex obtained by modifying a styrene-butadiene latex with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, itaconic acid, or the like in order to improve the adhesiveness and the water resistance.
The amount of the polyvinyl alcohol used in this invention is preferably 1.0 to 10.0% by weight, particularly preferably 2.5 to 6.0% by weight based on the activated clay, and the amount of the styrene-butadiene latex used is preferably 5.0 to 20.0% by weight (in terms of solids), particularly preferably 8.0 to 150% by weight (in terms of solids) based on the activated clay.
When the amounts of the polyvinyl alcohol and the styrene-butadiene latex are smaller than the above-mentioned lower limits, no sufficient fluidity can be obtained, and when they are higher than the above-mentioned upper limits, the coloring ability is lowered and hence the obtained sheet is unsuitable as a color developer sheet for no-carbon copying paper.
The wax used for preparing the wax emulsion used in this invention is solid at normal temperature. Examples of the wax include petroleum wax such as paraffin wax, microcrystalline wax, cresine wax, montan wax, powdered paraffin, oxidized paraffin, slack wax, and the like; and animal and vegetable wax such as Japan wax, white wax, carnauba wax, beeswax, castor wax, hardened wax, sugar wax, ibota wax, candelilla wax, and the like.
These waxes are solid at normal temperature, and therefore in adding them to a coating color for a color developer sheet for no-carbon copying paper, they cannot sufficiently been dispersed into the coating color unless they are emulsified.
Many of these waxes are commercially available in the form of an emulsion.
The preparation of a wax emulsion is explained below referring to the case of a 20% paraffin wax emulsion.
To 73.5 parts by weight of water is first added 1.5 part by weight of morpholine, and 5.0 parts by weight of oleic acid is subsequently added thereto with stirring, after which the resulting mixture is heated to a temperature near the boiling point, and heating and stirring are continued until a uniform soapy water is prepared. Twenty parts by weight of paraffin wax is melted in another vessel at 85.0° to 95.0° C., and the melted paraffin wax is gradually added to the aforesaid soapy water with vigorous stirring over a period of 5 minutes, after which the thus obtained mixture is cooled to room temperature with mild stirring.
A 20% paraffin wax emulsion is generally prepared by this process. As the emulsion stabilizer, there are those of acid-stabilizing type and nonion type in addition to the above-mentioned anionic type ones. However the emulsion stabilizer used in this invention is not limited thereto.
The amount of the wax emulsion is preferably 1.0 to 30.0% by weight (in terms of solids), particularly preferably 3.0 to 20.0% by weight (in terms of solids) based on the activated clay. When it is less than 1.0% by weight, the wax emulsion has no effect of preventing stains on the blanket, and when it is more than 30.0% by weight, the initial depth of developed color and the aptitude for pasting are reduced, so that the obtained sheet is unsuitable as a color developer sheet.
In this invention, a coating color for a color developer sheet is prepared by adding the polyvinyl alcohol, the styrene-butadiene latex and the wax emulsion to the activated clay, whereby the coating color is improved in dispersiveness at a high concentration and has excellent fluidity, and its coated amount becomes easy to control, and moreover the coating color can easily be fed to and recovered from the coater head, so that the workability of coating by means of a coater has greatly been improved.
There were obtained such effects that the color developer sheet obtained by coating a support such as paper with the above-mentioned coating color for a color developer sheet is free from stains on the blanket at the time of printing, shows no lowering of the depth of developed color, gives improved sunlight resistance of the colored characters, and is excellent in aptitude for pasting.
The term "high concentration" means that the coating color contains 45% or more of solids, but it is lower than a concentration used in ordinary coating.
Examples of this invention are described below.
As the color former sheet, commercially available top sheet "Mitsubishi NCR paper Joh-40" for no-carbon copying paper was used.
EXAMPLE 1
One hundred parts by weight of powdered activated clay was gradually added with stirring to a solution prepared by completely dissolving 0.5 parts by weight of sodium pyrophosphate in 60 parts by weight of additive water and then mixing therewith 50 parts by weight of a 10% aqueous solution of a polyvinyl alcohol (PVA-105 manufactured by Kuraray Co., Ltd., having a saponification degree of 98.5 mole % and a polymerization degree of 500). After the activated clay was sufficiently dispersed into said solution, 10 parts by weight (in terms of solids) of a styrene-butadiene latex (Dow 670 manufactured by Asahi Dow Co., Ltd., containing about 60% by weight of styrene) was added to the resulting dispersion, and the resulting mixture was well stirred. Thereafter 10 parts by weight (in terms of solids) of a paraffin wax (Cellosol A manufactured by Chukyo Oils and Fats, Co., Ltd. having a melting point of 53° C.) was added to the mixture and sufficiently dispersed thereinto, after which the pH of the thus obtained dispersion was adjusted to 9.5 with a 20% aqueous sodium hdyroxide solution to obtain a coating color. The coating color was applied to plain paper having 40 g/m 2 by means of a blade coater so that the applied amount might be 8 g/m 2 (in terms of solids), whereby a color developer sheet was produced.
EXAMPLE 2
A color developer sheet was produced in the same manner as in Example 1, except that the Cellosol A in Example 1 was replaced by an equal amount of Cellosol 866 (a paraffin wax emulsion manufactured by Chukyo Oils and Fats Co., Ltd., having a melting point of 60° C.).
Comparative Example 1
One hundred parts by weight of activated clay was gradually added with stirring to a solution prepared by completely dissolving 1.0 part by weight of sodium pyrophosphate in 60 parts by weight of additive water and then mixing therewith 50 parts by weight of a 10% aqueous solution of oxidized starch (MS-3800 manufactured by Nihon Food Co., Ltd.). After the activated clay was sufficiently dispersed into said solution, 10 parts by weight (in terms of solids) of a styrene-butadiene latex Dow 670 was added to the resulting dispersion, and the resulting mixture was well stirred, and then adjusted to pH 9.5 with a 20% aqueous sodium hydroxide solution to obtain a coating color. The coating color was applied to plain paper having 40 g/m 2 by means of a blade coater so that the applied amount might be 8 g/m 2 , whereby a color developer sheet was produced.
Comparative Example 2
One hundred parts by weight of powdered activated clay was gradually added with stirring to a solution prepared by completely dissolving 0.5 parts by weight of sodium pyrophosphate in 60 parts by weight of additive water and then mixing therewith 50 parts by weight of a 10% aqueous solution of oxidized starch (MS-3800). After the activated clay was sufficiently dispersed into said solution, 10 parts by weight (in terms of solids) of a styrene-butadiene latex (Dow 670) was added to the resulting dispersion, and the resulting mixture was well stirred. Thereafter, 10 parts by weight (in terms of solids) of a paraffin wax emulsion (Cellosol A) was added to the mixture and sufficiently dispersed thereinto, after which the pH of the thus obtained dispersion was adjusted to 9.5 with a 20% aqueous sodium hydroxide solution to obtain a coating color. The coating color was applied to plain paper having 40 g/m 2 by means of a blade coater so that the applied amount might be 8 g/m 2 (in terms of solids), whereby a color developer sheet was produced.
Comparative Example 3
One hundred parts by weight of powdered activated clay was gradually added with stirring to a solution prepared by completely dissolving 0.5 parts by weight of sodium pyrophosphate in 60 parts by weight of additive water and then mixing therewith 50 parts by weight of a 10% aqueous solution of a polyvinyl alcohol (PVA-105). After the activated clay was sufficiently dispersed to said solution, 10 parts by weight (in terms of solids) of an acrylic latex (Tocryl S-20 manufactured by Toyo Ink Co., Ltd., a copolymer of acrylic ester and styrene) was added to the resulting dispersion, and the resulting mixture was well stirred, and then adjusted to pH 9.5 with a 20% aqueous sodium hydroxide solution to obtain a coating color. The coating color was applied to plain paper having 40 g/m 2 by means of a blade coater so that the applied amount might be 8 g/m 2 (in terms of solids), whereby a color developer sheet was produced.
Test Methods
The thus obtained solutions and color developer sheets were subjected to various tests in the following manners.
(1) Coating color
(i) Viscosity
The viscosity (cps: centipoise) at 60 r.p.m. after 1 minute were measured by means of a B type viscometer (manufactured by Tokyo Meters Co., Ltd.) by using a rotor No. 4.
The viscosity curves were obtained by a Harcules II type high-share viscometer (manufactured by Nihon Science Industry Co., Ltd.)
(ii) Solid content
Each of the coating colors was dried at 110° C. for 16 hours and then its solid residue was measured.
(2) Color developer sheet
(i) Depth of developed color
The color developer sheet was put together with the color former sheet and they were passed through a calender under a pressure of 96 kg/cm 2 to develop color, and the reflectance (%) was measured by means of a colorimeteric color difference meter manufactured by Nihon Denshoku Co., Ltd., and the following value was determined. ##EQU1## (1 hour after passing the sheets through the calender) (ii) Sunlight resistance of colored characters
The color developer sheet colored by passing it through the aforesaid calender was exposed to the sun for 2 hours, and the reflectance (%) was measured by means of a colorimetric color difference meter manufactured by Nihon Denshoku Co., Ltd., and the following value was determined. ##EQU2## (iii) Surface strength
The measurement was carried out by means of an IGT tester (manufactured by Kumai Riki Co., Ltd.) by using IPI No. 4 ink and a B spring. The strength is expressed by or Δ .
(iv) Stains on blanket (piling)
The test was carried out by means of a Miyaster 17 type printer (manufactured by Miyakoshi Machine Factory) by using commercially available offset ink (blue). The degree of stains on blanket in this case is expressed by , Δ or X.
(v) Aptitude for pasting
A commercially available top sheet "Mitsubishi NCR paper Joh-40" for no-carbon copying paper and each of under sheets (the color developer sheets) obtained in Examples 1 and 2 and Comparatives Examples 1, 2 and 3 were put together to make a set of no-carbon copying paper, and 500 sets were piled up so that the top sheet and the under sheet might be alternately placed upon each other, and then cut. Commercially available "Adhesive for Mitsubishi NCR paper" (also called "paste") was applied to the transverse section and then dried, after which the bonding strength between the top sheet and the under sheet both of which constitute a set of no-carbon copying paper and the separability between the under sheet and the top sheet (between sets) were observed. The contact angle of the color developer sheets was also measured.
The bonding strength and the separability are expressed by o , , Δ or X.
Results
(1) Coating color
The solid contents, viscosities and fluidity of the coating colors used in Examples and Comparative Examples are shown in Table 1. The viscosity curves for the coating colors in Examples and Comparative Examples are shown in FIGS. 1, 2, 3, 4 and 5.
TABLE 1______________________________________ Solid B type Fluidity of content viscosity a coating color______________________________________Example 1 45.2% 1520 cps Good2 45.3 1500 "ComparativeExample 1 45.0 6050 Gelled2 45.5 5400 "3 45.8 5250 "______________________________________
It can be seen from Table 1 that as compared with the coating colors in Comparative Examples 1, 2 and 3, the coating colors in Examples 1 and 2 of this invention have greatly lowered viscosities and good fluidity, though they have the same solid contents as the former coating colors. As is obvious from FIGS. 1, 2, 3, 4 and 5, the coating colors in Comparative Examples 1, 2 and 3 have higher viscosities at high revolutions as compared with those in Examples 1 and 2, and even at low revolutions, they have high viscosities and are gelled.
(2) Color developer sheet
TABLE 2______________________________________ Sunlight Depth resistance of deve- of deve- Stains loped loped Surface on color characters strength blanket______________________________________Example 1 28.2 40.5 ○ ○2 28.3 40.9 ○ ○ComparativeExample 1 27.9 47.1 Δ○ X2 29.0 43.0 ○ Δ3 28.8 48.2 ○ X______________________________________ Marks used in Tables 2 and 3 have the following meanings. ⊚: excellent ○: good Δ○: worse than ○ but better than Δ: average X: bad
TABLE 3______________________________________Aptitude for pasting Contact Bonding angle strength Separability______________________________________Example 1 29° ⊚ ○2 27 ⊚ ○ComparativeExample 1 40 Δ○ ○2 65 X X3 22 Δ○ ○______________________________________
It is clear from Tables 1, 2 and 3 that the fluidity of a coating color is improved by adding a polyvinyl alcohol, a styrene-butadiene latex and a wax emulsion to solid (powdered) activated clay previously incorporated with a dispersant, and that a color developer sheet obtained by using said coating color shows improved sunlight resistance of colored characters. Further stains on the blanket at the time of printing is prevented and excellent aptitude for pasting is brought about. | There is disclosed no-carbon copying paper composed fundamentally of a color former sheet produced by coating a support with microcapsules containing a colorless electron-donative organic compound as a color former and a color developer sheet produced by coating a support with a coating color containing activated clay as a color developer which adsorbs the aforesaid electron-donative organic compound to develop color. When said coating color is prepared by adding a polyvinyl alcohol, a styrene-butadiene latex and a wax emulsion to the activated clay, it becomes possible to apply it at a high concentration and there are accomplished the maintenance of surface strength of the color developer sheet, the decrease in stains on the blanket and the improvement in sunlight resistance of the colored characters and in the aptitude for pasting. | 8 |
The Government has rights in this invention pursuant to Contract No. F33615-76-C-5251 awarded by the Department of the Air Force.
FIELD OF THE INVENTION
The present invention relates to the measurement of preload on a threaded fastener and more particularly to a threaded fastener incorporating a removable ultrasonic transducer for allowing accurate measurements of preload to be obtained as well as other measurements for quality control inspection or for monitoring purposes.
DESCRIPTION OF THE PRIOR ART
In aircraft, space vehicles, and other types of vehicles, it is important that bolt fasteners be properly preloaded (tightened) to prevent structural failure. This is particularly true with respect to fasteners employed in critical load bearing structures. It has been found that the conventional hand operated torque wrench may result in errors of 30% or higher in pretensioning a bolt to the desired preload. Thus means is desired that will accurately measure the true preload on a bolt.
Pulse-echo and resonant frequency techniques have been developed to obtain more accurate measurements of the preload obtained on a bolt when torqued. Pulse-echo techniques are disclosed in U.S. Pat. Nos. 3,759,090 and 3,969,810 and a resonant frequency technique is discussed by Heyman, J. S., "Ultrasonic Bolt Stress Monitor" Industrial Research, Oct. 1976; Lutz-Nagey, R. C., "Torque Verification from Eyeball to Accuracy," Automation, October 1976; and Langley Research Center, "ROUS Bolt Tensioning Monitor," NASA Tech Brief, Summer 1976. The pulse-echo technique is preferred over the resonant frequency technique since it is more accurate and allows measurements to be obtained faster.
In the prior pulse-echo and resonant frequency techniques employed in making preload measurements, an ultrasonic transducer is temporarily clamped to the head of the bolt with an acoustic coupling oil or other suitable coupling medium located between the transducer and the bolt. U.S. Pat. No. 3,759,090 discloses a manual clamping technique while U.S. Pat. No. 3,969,810 discloses an automatic torque wrench which carries the transducer in the wrench head and allows measurements to be obtained while torquing.
In these prior techniques, the transducer is clamped to the fastener only during preloading measurements and can not be used for making subsequent measurements on the fastener or for monitoring purposes. Moreover, an automatic torque wrench which carries the transducer in the wrench head has disadvantages in that slippage occurs between the transducer and the bolt head during torquing. In the pulse-echo technique, this slippage introduces a time error which even though only a few nanoseconds, is enough to prevent accurate time measurements.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a threaded fastener which carries a removable (or replaceable) transducer; i.e., in a semi-permanent manner, which may be employed to readily obtain accurate preload measurements without slippage as well as subsequent measurements to detect for flaws or cracks or which may be employed subsequently for monitoring purposes.
It is a further object of the present invention to provide a threaded fastener carrying an attaching means for attaching an acoustic transducer to the fastener whereby the transducer also will be carried by the fastener. The attaching means allows the transducer to be removed for repair or replacement purposes.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 illustrates a conventional threaded fastener.
FIG. 2 is an enlarged cross section of the head of a fastener similar to FIG. 1 illustrating one embodiment for removably attaching a transducer to the head.
FIG. 3 illustrates a snap ring which may be used in the embodiment of FIG. 2.
FIG. 4 illustrates another embodiment for removably attaching a transducer to the top of a fastener.
FIG. 5 illustrates an automatic torque wrench torquing a fastener of the present invention in place while preload measurements are obtained.
FIG. 6 illustrates a hand wrench torquing a fastener of the present invention in place while preload measurements are obtained.
FIG. 7 is an electrical block diagram of a system of circuitry for obtaining preload or other measurements.
FIG. 8 are timing diagrams useful in understanding the system of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1 of the drawings, reference numeral 21 identifies a conventional metallic fastener or bolt used in aircraft, space vehicles, and in other types of vehicles for securing structural members together. It may be formed of steel, titanium, aluminum, or other metals or alloys. The fastener comprises a shank 23 having a head 24 formed at one end and threads 25 formed at the other end 27 to which a nut may be threaded.
Referring to FIG. 2, a cylindrical opening 31 or recess means is formed in the top center of the head 24 from its flat surface 33 downward toward the shank. Removably secured in the opening 31 is a cylindrical metallic member 29 carrying an ultrasonic transducer element 35 formed of a piezoelectric material such as Pb Zr Ti. The transducer is disc shaped and has thin layers of electrically conducting metal 37 and 39 secured to opposite ends or surfaces 41 and 43 respectively. Layers 37 and 39 may be secured to ends 41 and 43 by conventional techniques. Secured to layers 37 and 39 are electrodes 45 and 47 respectively which may be tin strips secured in a conventional manner. Secured within the lower end of member 29 is a layer of material 51 (which may be suitable plastic) having good acoustic coupling properties. The transducer element 35 is located such that its electrode 47 rests against layer 51 and is embedded in member 29 by a potting material 53 which has good acoustic damping properties. Electrode 45 is in electrical contact with a metallic pin terminal 55 held in place by the potting material 53. Electrode 47 extends upward and is electrically connected to member 29 allowing its neck 29A to be employed as a terminal. The potting material damps out ultra sound vibrations traveling upward toward terminal 55. A layer of oil, grease or other suitable media 59 is located between layer 51 and the lower surface 31A of opening 31 for purposes of acoustic coupling.
Member 29 and hence transducer element 35 is held in the opening by a C-shaped snap ring removably located in slot 63. Located below the snap ring 61 is a washer 65 which acts a dust cover. A coil spring 67 engages the lower surface of the washer 65 and the outer portion of the shoulder 29B of member 29 to urge member 29 and its layer 51 tightly in the opening against the coupling medium 59. In order to remove member 29 and hence the transducer for replacement or other purposes, one merely has to remove the snap ring 61 and lift the member 29 out of the opening 31.
Since the transducer is carried by the fastener, preload measurements may be readily made while torquing with an automatic torque wrench and a permanent record may be obtained of each preload. No slippage will occur between the transducer and the bolt head. In addition, at a later date, the transducer may be used to recheck preload or to detect for flaws or cracks in the bolt fastener or to monitor for acoustic emissions resulting from bolt or adjacent structural failure. If the transducer deteriorates or becomes faulty, it can be readily replaced or repaired.
In using the embodiment of FIG. 2 for measurement or monitoring purposes, circuitry will be electrically coupled to terminal 55 and terminal 29A will act as a return terminal.
It is to be understood that member 29 and its transducer element 35 may be removably secured with snap ring 61 in an opening (not shown) formed in the bottom end 27 of the bolt 21 instead in opening 31 of the bolt head. The transducer may be used in the same manner as when removably secured in the opening 31 of the head 24. The embodiment wherein the transducer element 35 is removably secured in an opening formed in end 27 of the fastener will not be employed when the fastener is torqued into a threaded opening in a structural member.
Referring now to FIG. 4, the member 29 with its transducer element 35 is shown removably secured to the top surface 33 of the fastener 24 by way of a cap 71 and bolts 73. As shown, cap 71 fits around the member 29 with its neck 29A extending through an upper opening 75 formed in the cap. A coil spring 77 engages the upper inner surface of cap 71 and the outer edge of shoulder 29B for urging the member 29 and its layer 51 tightly against the coupling medium 59. In order to remove member 29 and hence transducer element 35 for replacement or other purposes, one merely has to remove bolts 73 and the cap 71. In the embodiment of FIG. 4, since the transducer is carried by the fastener, preload measurements can be readily made while torquing with an automatic or manual torque wrench and a permanent record may be obtained of each preload. No slippage will occur between the transducer and the bolt head. In addition, at a later date, the transducer may be used to recheck preload or to detect for flaws or cracks in the bolt fastener or to monitor for acoustic emissions resulting from bolt or adjacent structural failure. If the transducer deteriorates or becomes faulty, it can be readily repaired or replaced.
It is to be understood that the cap 71 may be employed to removably secure member 29 and its transducer element to the threaded end 27 of the fastener instead of to the top of the bolt head 24.
Pulse-echo time measurements for preload may be made with the embodiments of FIGS. 2-4 whether the fastener is torqued with an automatic wrench or with a manual wrench. In FIG. 5, the bolt 21 and a nut 81 are employed to fasten together two plates 83 and 85. The bolt 21 employs the embodiments of FIG. 2. A power driven wrench 87 is shown in outline form for torquing the fastener and the nut 81 together. The means for holding the nut 81 is not shown. The wrench 87 has a socket 96 pneumatically driven or electrically driven. Reference numeral 88 identifies pneumatic or electrical lines for applying power to the wrench. An electrical socket 89 is fitted to terminals 55 and 29A for connecting the terminals to leads 90 and 91 respectively. Leads 90 and 91 are coupled to leads 92 and 93 respectively by way of means 94 which allows leads 90 and 91 to rotate relative to leads 92 and 93. Leads 92 and 93 are electrically connected to a pulse-echo measuring system 95. When good pulse-echo signals are being detected within the desired electronic time window or windows, a light will turn on signaling to the operator to actuate the trigger 98 to apply power to the wrench to tighten the bolt. When the desired preload or stress is achieved, the system 95 issues a command by way of line 99 to cut off power to the wrench. If too much stress is measured, the system 95 will issue a command to the wrench (by means not shown) to back off until the desired stress is achieved.
When the fastener has been tightened to the desired preload, the socket 96 of the wrench 87 is removed and member 29 with its transducer element 35 are left in place attached to the fastener. The transducer may be used at a later time to recheck preload or to detect for flaws or cracks or to monitor for acoustic emissions resulting from structural failure.
In FIG. 6, the bolt 21 is employed to fasten together plates 101 and 103, the latter of which has threads 105 formed within its aperture. The bolt 21 employs the embodiment of FIG. 2. A manual wrench 107 is shown for torquing bolt 21 into threads 105 for fastening together plates 101 and 103. An electrical socket 109 is fitted to terminals 55 and 29A for connecting these terminals respectively to leads 111 and 113 which extend to the pulse-echo measuring system 95. A meter 115 is employed to measure torque by the pulse-echo technique while the bolt 21 is being torqued by wrench 107. When the desired preload is achieved, the wrench 107 is removed and member 29 with its transducer element 35 is left in place attached to the bolt. The transducer may be used at a latter time to recheck preload or to detect for flaws or cracks in the bolt or to monitor for acoustic emissions resulting from structural failure.
Referring now to FIGS. 7 and 8, there will be described a preferred pulse-echo technique for measuring preload stress. For these measurements, the transducer will have a frequency of from 0.5 MHZ to 200 MHZ. A pulser 121 is employed for pulsing the transducer at a repetition rate of 100-2000 pulses per second. Each time the transducer is pulsed, an acoustics signal will travel to the end of the bolt and back a number of times until the signal is attentuated or damped out. Preferably the first and second back echos (signals reflected from the other end of the fastener) are measured and the time difference between the signals is determined. In FIG. 8A, 123 represents an acoustic pulse generated by the transducer element 35 when it is pulsed. The first back echo is identified at a and the second back echo is identified at b. Signal 125 is an echo signal due to reflections from interfaces between coupling layers. For example, in FIG. 2 such a signal will be produced from interfaces between layers 51, 59, and surface 31A. The signals to the right of signal b are third, fourth, and fifth back echo signals. The times of the first and second back echo signals a and b are measured and the difference obtained to subtract out the travel times in any acoustic medium employed. The time difference is indicated to be equal to T. The time T is measured prior to preload to obtain T 0 and during torquing to obtain T t . The difference between T t and T 0 is found to obtain ΔT as follows.
ΔT=T.sub.t -T.sub.0 (1)
It can be shown that stress S on the bolt is equal to ##EQU1## wherein:
M is a material constant,
δ is the grip length (See FIGS. 5 and 6),
D is the diameter of the shank of the fastener, and
α is an empirically determined parameter which corrects for stress distribution in fasteners. This has been experimentally determined for typical high strength steel fasteners to be about 0.6.
In obtaining measurements of the first and second back echo signals a and b, two electronic time windows are set following the pulse 123 where signals a and b are expected to occur. The position of these windows depend upon the length of the fastener and the velocity of sound in the material of the fastener. Thus, knowing the properties of the material of the fastener, its length and diameter, and the grip length, one can measure ΔT to measure stress to obtain an accurate measure of bolt preload.
Referring again to FIGS. 7 and 8, the output of transducer at A is shown in FIG. 8A. This output is applied to a pre-amplifier 127, a receiver amplifier 129, and a detector integrator 131 whose output is shown in FIG. 8B. Detector integrator 131 is a full wave rectifier and integrator. Start and stop gate generators 133 and 135 produce gating signals at times T a and T b when the first and second back echo signals are expected respectively. Their outputs are shown in FIGS. 8C and 8D respectively. Dual voltage controlled pulse height circuit 137 converts the first and second back echo signals passed to it at times T a and T b to the same heights to correct for attentuation in the fastener. The output of circuit 137 at E and F are shown in FIGS. 8E and 8F respectively. These output signals are applied to dual amplitude comparitor circuit 139 where they are converted to square wave signals shown at 141 and 143 in FIGS. 8G and 8H respectively. These signals then are applied to a time interval counter 145 which counts the time between the leading edges of square wave signals 141 and 143 to obtain T. The leading edge of square wave signal 141 turns on the counter and the leading edge of square wave signal 143 turns it off. As stated above, T 0 is measured prior to preload and T t is measured during torquing to obtain ΔT and hence stress. Circuitry will be provided for averaging ΔT over a plurality of cycles and for automatically solving equation 2.
In the system of FIG. 7, pulser 121 is a free-running pulser which produces a pulse at a repetition rate of 100-2000 pulses per second. The logic in timing circuits 147 senses each pulse and sends a signal to start the two gate generators 133 and 135 during each cycle. It also sends a signal to the dual voltage controlled delay circuit 149 which starts two timers. The timers may be charging capacitors, one of which charges at a rate twice as fast as the other. A voltage representative of the two way travel time between the transducer and the other end of the fastener is applied to circuit 149 at 151 and compared with the voltages of the timers. When the voltages of the timers reach the level of the input voltage at 151, the timers are cut off and their associated gate generators are caused to generate the gating signals T a and T b .
In order to detect for flaws or cracks in the fastener, one merely needs to look at the output of the detector integrator 131 on a oscilloscope or readout. The absence of one or both of the signals a' and b' or changes in their heights indicates possible flaws in the fastener. The appearance of another signal between 123' and a' indicates that the fastener has a crack in it.
One may use the embodiments of FIGS. 2-4 to look for acoustic emissions or for other diagnostic purposes while the vehicle is in operation or flight and which may result from bolt or adjacent structural failure. In this embodiment, the pulser 121 will not be employed. The output of the transducer will be coupled to circuits 127, 129, and 131 and the output of circuit 131 will be monitored. FIG. 6 illustrates one way in which acoustic emissions, which may occur while the vehicle is in operation or in flight due to bolt or adjacent structural failure, may be monitored. The embodiment of FIG. 2 is shown in this figure. The system 93 will have a suitable readout for monitoring for acoustic emissions from the bolt or from the adjacent structure.
The system of FIG. 6 also may be used to allow one to monitor for cracks or flaws in critical fasteners periodically or continuously during operation or while in flight. In this embodiment, the pulser 121 will be employed and the output of the detector integrator 131 will be monitored as described previously.
Since the transducer is carried by the fastener, improved quality control can also be obtained. In this respect, the fastener can be tested prior to use to determine if good echo signals are received or if other noise signals appear as described above. If flaws or cracks exist, the fastener may be discarded.
As now can be understood, accurate preload measurements can be readily obtained using the fastener of the present invention. There will be no slippage between the transducer and the fastener during torquing and in addition, assurance will be had that optimum echo signals will be obtainable. Moreover, subsequent measurements can be readily made with the same transducer to recheck for preload and to measure and monitor for cracks and flaws and for acoustic emissions. In the event that the transducer deteriorates or becomes faulty at a later date it may be readily repaired or replaced.
Although pulse-echo techniques were described in making measurements employing the fasteners of the embodiments of FIGS. 2-4, it is to be understood that the embodiments of FIGS. 2-4 may be used in obtaining preload measurements employing resonant frequency techniques. | A threaded fastener incorporating a removable ultrasonic transducer for obtaining preload measurements as well as other measurements for quality control inspection or for monitoring purposes. The transducer may be removed for repair or replacement purposes. | 6 |
BACKGROUND OF THE INVENTION
The present invention is related to a Wollaston prism formed by two birefringent wedges having optic axis to each other at right angle, to a Fourier-transform spectrometer comprising said Wollaston prism, and to a method to adjust said Fourier-transform spectrometer.
A Wollaston prism is comprised of two similar wedges of birefringent material joined by their hypotenuse to form a rectangular block. The optic axes within the two wedges are aligned perpendicular to each other and parallel to the entrance/exit faces of the composite block. The angle of refraction at the internal interface of the Wollaston prism depends on the polarization state of light and hence leads to the customary use of a Wollaston prism as a polarizing beam splitter.
Conventional Fourier-transform spectrometers are based on Michelson interferometers. When the output of the interferometer is recorded as a function of the path difference between two arms, an interferogram is obtained that is the autocorrelation of the optical field. The power spectrum of the Fourier transform of the interferogram corresponds to the spectral energy or power distribution of the input light. Draw-backs associated with these instruments are that high quality mirror-scanning mechanisms are required, and the temporal resolution is limited by the maximum mechanical scanning rate.
As an alternative, a Wollaston prism may be used in a Fourier-transform spectrometer with no moving parts. It is well known in the state of the art that when a Wollaston prism is placed between two suitably oriented polarizers and illuminated with a light source, a set of straight-line interference fringes will be produced localized to a plane within the prism. These fringes are the Fourier transform of the spectral power distribution.
Although the use of Wollaston prisms in Fourier-transform spectrometers has been proposed earlier, it could not be applied without a suitable scanning device having a high resolution. Such a high-resolution scanning device has been described by Takayuki Okamoto et. al. in “A Photodiode Array Fourier Transform Spectrometer based on a Birefringent Interferometer” (Applied Spectroscopy 40, p. 691 to 695, 1986).
The varying path difference across the Wollaston prism of the above-mentioned Fourier-transform spectrometer results in the formation of interference fringes localized to a imaging plane within the Wollaston prism. For that reason, an imaging lens must be provided to image the interference plane onto the scanning device in order to obtain best results with regard to the contrast of the image.
All of the above-described Fourier-transform spectrometer have the general draw-back that the angle of incidence for a light beam to be analyzed is very small, i.e. measures must be taken to reduce the angular extent of this light beam and the spectrometer must be precisely adjusted in order to obtain acceptable results.
To overcome this draw-back, a design of a static Fourier-transform spectrometer based on a Wollaston prism has been presented by J. Courtial et. al. in “Design of a static Fourier-transform spectrometer with increased field of view” (Applied Optics, Vol. 35, No. 34, Dec. 1, 1996, p. 6698-6702). The field of view is increased by including an achromatic λ/2-plate (λ: wavelength) between the prisms or by combining prisms fabricated from positive and negative birefringent materials. These materials are expensive and are therefore not suitable for any mass product.
SUMMARY OF THE INVENTION
An object of the present invention is to eliminate the above mentioned draw-backs, in particular, the object of the present invention is to increase the maximum angle of incidence of light, i.e. the field of view (angle acceptance), and, at the same time, using inexpensive materials for obtaining best results.
The present invention is directed toward a Wollaston prism formed by two birefringent wedges joined by their hypotenuses to form a block. The wedges have optic axes that are at right angles to each other and are rotated by an angle with regard to a position wherein one of the optic axes is parallel to a plane formed by their hypotenuses. Further advantageous embodiments of the present invention, a Fourier-transform spectrometer and a method to adjust said Fourier-transform spectrometer are also provided by the present invention.
The present invention has the following advantages: By making use of optical axes orientation of 45° and 135°, respectively, the field of view for the Wollaston prism is increased.
The field of view can even further be increased as follows: Unlike the above-mentioned prism of the prior art, the Wollaston prism of the invention shows a non-homogeneous orientation (or twist) of the optic axes within the wedges. Such twist causes a polarization rotation of the incident light polariszation by 45°, 90°, 135° and 180°, respectively.
Liquid crystal is a material which is very inexpensive compared to the materials of the state of the art. In turn, it is possible to provide inexpensive Fourier-transform spectrometers.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplified embodiments of the present invention will be described in the following referring to drawings, which show in
FIG. 1 a known Fourier-transform spectrometer comprising a Wollaston prism,
FIG. 2 an interference fringe pattern resulting from illuminating the Wollaston prism represented in FIG. 1,
FIG. 3 a polarization interferometer with a cylindrical lens focusing the light on a scanning device,
FIG. 4 an interference fringe pattern of 45°-Wollaston prism according to the present invention,
FIG. 5 a Wollaston prism according to the present invention having liquid crystal elements that induce a polarization rotation of 90°, and
FIG. 6 a further Wollaston prism according to the present invention having liquid crystal elements that induce a polarization rotation of 90°.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, an arrangement is represented for a known spectrometer using a Wollaston prism WP. The spectrometer comprises two polarizers P 1 and P 2 , the Wollaston prism WP in between the two polarizers P 1 and P 2 , an imaging lens IL and a scanning device SD.
By the polarizer P 1 , a monochromatic input light ML is linearly polarized at 45° to optic axes OA 1 and OA 2 of the Wollaston prism WP, giving equal transmission intensities for the horizontally and vertically polarized components. A second 45° polarizer P 2 placed after the Wollaston prism WP analyzes the transmitted light, permitting the two orthogonal polarizations to interfere. It can be shown, that a path difference between the two components depends on the lateral position across the Wollaston prism WP. The varying path difference across the Wollaston prism WP results in the formation of interference fringes localized to a interference plane IP within the Wollaston prism WP. The imaging lens IL images the interference plane IP onto the scanning device SD, and the resulting interferogram IG is recorded with a microprocessor (not shown in FIG. 1 ).
The above-mentioned Fourier-transform spectrometer is further described in “Single-pulse, Fourier-transform spectrometer having no moving parts” by M. J. Padgett et. al. (Applied Optics, Vol. 33 (4), p. 6035-6040, 1994) or in “A Photodiode Array Fourier-Transform Spectrometer based on a Birefringent Interferometer” by Takayuki Okamoto et. al. (Applied Spectroscopy, Vol. 40, p. 691-695, 1986).
To obtain best results regarding the signal to noise ratio of the interferogram and, therefore, also of the power spectrum, it is important to increase the incidental light on the scanning device as much as possible. This can be achieved by, for example, a cylindrical lens by which the angle of incidence (angle acceptance) is increased. Through the increased angle of incidence the interferogram is displaced and the contrast is therefore decreased. The maximum angle of incidence is different for each type of interferometer, and it is the aim to have the largest possible angle of incidence.
Several methods have been proposed to increase the angle acceptance. For example, M. Fracon et. al. have proposed in “Polarization Interferometers” (Wiley-Interscience London, N.Y., 1971) to compensate the birefringence of the Wollaston prism using two birefringent plates with an anisotropy having opposite signs. Unfortunately, this known teaching has the draw-back that rather expensive crystals must be used to obtain positive and negative birefringence. Another possibility, proposed by the same authors, consists in using an achromatic λ/2-delay plate to rotate the polarization vector by 90° between two identical birefringent wedges.
FIG. 2 shows a interference fringe pattern IG resulting from illuminating the Wollaston prism WP of FIG. 1 by divergent light DL. Curved interference fringes are caused by different angles of incidence, whereas a circular range R is drawn by a dashed line in the interference fringe pattern IG, in which range the phase distortion is equal to or less than λ/4.
In FIG. 3, a Wollaston prism is WP represented having a cylindrical lens CL on the side of a light source LS the light of which shall be analyzed. The light of the light source LS is focused on a scanning device SD by the cylindrical lens CL. The arrangement according to FIG. 3 is particularly advantageous for a compact construction of a spectrometer since no additional optics are used between the Wollaston prism WP and the scanning device SD. In addition, the vertical angle of incidence α V is increased in direction perpendicular to the orientation of the scanning device SD.
Furthermore, the optic axes of the birefringent wedges of the known Wollaston prism are both rotated by 45° to obtain a Wollaston prism WP according to the invention for which, in return to the polarization rotation of the optic axes, the phase deviations, in function of the angles of incidence, are now rotated by an azimuth angle of 45°. This so called 45°-Wollaston prism WP and the corresponding phase deviations are represented in FIG. 4 . As in FIG. 2 for the known Wollaston prism, the phase deviations for the 45°-Wollaston prism according to the invention are shown in a interferogram IG. Through the comparison of the ranges R representing phase deviations of less than λ/4 shown in FIGS. 2 and 4, it becomes apparent that the range R in FIG. 4 is now larger for the Wollaston prism according to the invention than the range R in FIG. 2 for the known Wollaston prism. Besides the clear increase in the angle tolerance, the angle of incidence depends on the horizontal angle of incidence α H whereas the result of the multiplication of the two angles of incidence α H and α V remains constant.
In FIG. 5, a Wollaston prism WP according to the present invention is shown consisting of two birefringent wedges W 1 and W 2 made of liquid crystal. The wedges W 1 and W 2 represent each a polarization rotation cell for an angle of 45°. On the right hand side of FIG. 5, the polarization rotation (twist) of the optic axes within the two liquid crystal wedges are shown. The Wollaston prism according to the present invention is obtained by providing a 90°-angle between the succeeding orientation planes of both liquid crystal wedges W 1 and W 2 in order that interference fringes are generated in the middle of the element and in order that symmetrical interferograms are obtained.
The use of nematic liquid crystals is particularly advantageous since they have the characteristics to be birefringent and also to possess the possibility of making them optical active. A definition of nematic liquid crystals can be found in “Introduction to liquid crystals” by E. B. Priestley et. al. (Plenum Press, New York and London, 1975, p. 16). In addition, the optical activity which is generated in the liquid crystal is achromatic, as desired in this application.
Besides liquid crystal wedges which provide a polarization rotation of 45°, it is also proposed according to the invention to provide Wollaston prisms with a higher angle of polarization rotation, e.g. of 90° or 180°. Depending on an application, different parameters, such as birefringence, optical activity, corresponding direction of polarization rotation, or maximal optical path difference must be optimized.
In FIG. 6, a Wollaston prism WP which provides a polarization rotation of 90° is represented. As in FIG. 5, the polarization rotation of the optic axes within the two liquid crystal wedges are shown on the right hand side.
As has been pointed out, it is a typical characteristic of the known Wollaston prism that the interference fringes are located within the Wollaston prism. To overcome this problem and in order to detect or record an interferogram with high contrast, it is known in the state of the art to provide an imaging system by which the interference plane can be transferred to the outside of the Wollaston prism.
Using liquid crystals for the birefringent wedges of a Wollaston prism, the interference plane can be transferred to the outside of the Wollaston prism by tilting the optic axis in one of the birefringent wedges. By using a Wollaston prism according to the invention a spectrometer is obtained that is very compact and, due to the low costs of liquid crystals, is very inexpensive.
It has already been pointed out that for increasing the angle acceptance (field of view) the use of a λ/2-delay plate between two identical birefringent wedges can be used. To significantly reduce the costs for such an arrangement, the λ/2-delay plate can be replaced by a twisted nematic cell which rotates the polarizing vector by 90°. Besides the cost reduction, a further advantage is obtained. The liquid crystal polarization rotation cell according to the invention provides a polarization rotation characteristic over a wide spectral range. Furthermore, the use of a 90°-liquid crystal polarization rotation cell in a Wollaston prism with an increased angle acceptance bears the advantage of having electro-optical characteristics which make the Wollaston prism switchable: By applying an electrical field, no polarization rotation occurs, the illumination intensities can be measured whereas the results of this measurement can be used to compensate any irregularities in the illumination. Without an electrical field, the interferogram can be recorded. | The present invention is related to a Wollaston prism (WP) comprising two birefringent wedges (W 1, W 2 ) joined by their hypotenuse to form a composite block, said wedges having optic axes (OA 1, OA 2 ) to each other at right angle. According to the invention, the optic axes (OA 1, OA 2 ) of said wedges (W 1, W 2 ) are rotated by an angle of 45° or 135°, respectively, with regard to a position wherein one of the optic axes (OA 1, OA 2 ) lies parallel to the plane formed by the hypotenuse.
In an embodiment of the present invention, liquid crystal is used as material for the wedges (W 1, W 2 ) resulting in inexpensive and easy to handle Wollaston prisms. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to marine risers for deep subsea drilling and production and in particular to a coupling assembly therefor.
Marine risers are run from floating vessels or platforms to subsea wellheads for drilling and production operations. The riser sections are tubular, in the order of 20 inch diameter and 50 feet long. They are assembled at the surface and are run from the vessel to the wellhead. In assembling these, a successive section is first stabbed into a preceding section and the connector then bolted up. Accordingly, easy stabbing is desired.
The riser is usually highly tensioned at the upper end to avoid buckling and is also subject to cyclical bending caused by current and/or vessel drift. The riser must remain leak tight over its life to prevent ingress of sea water and/or leakage of mud during drilling, and potential oil during production. This despite the cyclical loading placed thereon.
Handling of large risers sections can cause damage to the couplings. A design tolerant of such damage and/or one easily repaired is therefore desirable.
SUMMARY OF THE INVENTION
The coupling assembly is comprised of a pair of couplings, at the end of an adjacent marine riser pipe sections with a tubular pin insert fitting within the couplings. Each coupling is flanged with the flange being integral with a tubular portion of the connector which is in turn welded to the riser pipe section.
The tubular portions of each coupling have a portion of the inside diameter greater than that of the riser pipe sections to which they are connected and the pin fits within this larger diameter portion, preferably having an inside diameter approximately equal to that of the adjacent riser pipe sections. The flanges have a plurality of alignable bolt holes and a plurality of bolts secure the flanges together in mutually contacting relationship.
The pin is radially sealed to the coupling with the groove in the pin containing an O-ring. A contractable retaining ring operates in a groove within the pin and a groove within the coupling to secure the pin within one of the couplings.
Stabbing is facilitated since the pin insert has a small diameter portion near its outboard end and a larger diameter portion towards its center. Furthermore, the stabbing overlap between the pin insert and coupling is greater than the stabbing overlap between attached choke and kill lines so that the initial stab is made over the insert and the riser may thereafter be rotated to easily stab the choke and kill lines.
Both couplings are preferably identical so that the pin inserts may be located in either coupling, thereby providing the ability to run the riser either pin up or pin down as desired. Furthermore, should the pin be damaged it may be removed and replaced. Any repair work need be done only on the relatively easy handled pin insert rather than handling the entire riser section.
Even a rigidly bolted flanged connector has some movement during bending as experienced by the riser. Even if the pin insert were forced in with an interference fit it would be loose compared to a pin which is machined at the end if a riser section. Accordingly, bending strain of the connector is absorbed at two ends of the pin thereby taking half of the differential movement at each end. This minimizes the differential movement which must be taken by the seals thereby improving the long term sealing of the connector.
Even with the most precise machining of large couplings is known that some out of roundness develops after the machining has been completed. With a pin integrally formed with one of the flanges, out of roundness of the adjoining sections cannot be readily absorbed by deflection of the pin. With the relatively loose pin insert, which is not reinforced by a flange, it may deflect to absorb the out of roundness of the adjoining sections, thereby improving the sealing capabilities.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional elevation of a completed connector assembly;
FIG. 2 is a sectional elevation of the pin insert;
FIG. 3 shows a detail of the pin insert and the cooperating retaining means; and
FIG. 4 is a sectional elevation of the coupling just prior to stabbing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Marine riser pipe sections 10 and 12 have couplings 14 and 16 welded thereto at locations 18 and 20. Each connector includes a tubular portion 22 and 24 and a flange portion 26 and 28 integral therewith.
Each tubular portion has a portion of the inside diameter 30 greater than the inside diameter 32 of the riser section. The inside diameter 34 of pin insert 36 is substantially the same as the inside diameter of the riser pipe section.
The pin insert is tubular and has the outside of each end substantially conforming to the inside shape of the corresponding tubular portion. The pin is also located entirely within the tubular portion.
Each tubular portion has a box retaining groove 38 and 40 around the inner periphery. A pin retaining groove 42 is located on the outer periphery of the pin insert 36. A split retaining ring 44 is located partially within the box retaining groove and remains partially within the pin retaining groove so that the pin insert 36 is retained within connector 16.
The flange portion of each coupling has a plurality of alignable bolt holes 46 with a plurality of bolts 48 securing the flanges together in mutually contacting relationship.
The pin insert 36 has a first larger outside diameter 50 toward its central portion and a second lesser diameter 52 toward its outboard end. As best seen in FIG. 4 this facilitates initial stabbing of the connector.
Each of the connectors is identical. While box retaining groove 38 is not used as illustrated, the retaining ring could be located in the upper portion of the pin insert groove so that the pin insert is retained in the upper connector 14 rather than the lower connector 16.
Retaining ring 44 is preferably inwardly biased so that it is normally in the position illustrated in FIG. 2. In any event the ring must be compressed to this position for installation of the pin insert 36 within coupling 16. Locking ring 54 is held at this time in the upward position shown in FIG. 2.
When the pin insert has been placed within the coupling, if the retaining ring 44 snaps outwardly into groove 40, the locking ring 54 is simply moved down to backup the retaining ring. If the retaining ring does not snap outwardly, face 56 of the locking ring will force the retaining ring outwardly as retaining ring 54 is moved down. After the locking ring 54 has been moved downwardly a blocking ring 58, which may be in the form of a O-ring, is inserted above the locking ring thereby guarding against undesired upward movement of the locking ring.
A notch 60 on the locking ring permits it to be grasped for upward movement during disassembly of the connection. Furthermore, should the retaining ring not disengage, a 45° face 62 urges the ring inwardly on upward movement of the pin insert.
A radially sealing means in the form of an O-ring 66 in groove 68 is provided on the smaller diameter portion of the pin insert at one end. A similar O-ring 70 in groove 72 is located on the opposite end of the pin insert. On the larger diameter portion of the pin insert, O-rings 74 are located in grooves 76 providing a second sealing means on each end of the pin. These not only provide double sealing on each end of the pin but they contribute to the centering of the pin inserts within the tubular portion thereby improving the sealing ability of each of the O-rings.
The pin is free to remove with respect to the couplings by slight amounts since it is not welded to either. Accordingly, strain occurring in the couplings under bending can be absorbed at both ends of the pin insert as contrasted the connectors where the pin is integrally formed with one of the couplings. Therefore, differential movement between the sealing surfaces is cut in half, thereby improving the ability of the connector to seal throughout the cyclical bending which occurs.
Choke and kill lines 80 and 82 are loosely secured to corresponding flanges 26 and 28, line 80 has a female stab connection 84 or line 82 has a male stab connection 86.
The stab overlap is the depth of penetration of the stabbed connection. It follows that the stab member with the maximum stab overlap will be the first to engage during the stabbing operation. As best seen in FIG. 4 the initial stabbing engagement occurs between outside diameter 52 of the pin insert 36 and the outside diameter 30 of connector 14, this being the portion of the connector with the maximum stab overlap. This difference in diameters simplifies the initial stabbing of the connection.
After guidance from the initial stab the larger outside diameter 50 of the pin insert 36 engages the inner surface 30 bringing the connection into accurate alignment. This stab overlap is greater than that of the choke and kill lines.
After achieving the proper rotation for the choke and kill lines to engage the stab is fully made engaging connector 86 and 84 of the choke and kill lines.
The flange is thereafter securely tightened with a plurality of bolts 48. | A marine riser coupling assembly comprised of a pair of flanged couplings (14, 16). A pin insert (36) is retained (44, 54) within tubular portions (22, 24) of the couplings. The insert has multiple outside diameters (50, 50), and seals (66, 74) on each. | 4 |
RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 137,329 filed Apr. 4, 1980, now U.S. Pat. No. 4,305,745, the disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
This invention relates to a method for manufacturing flat glass wherein the glass is formed into a flat sheet while supported on a surface of a pool of molten metal, commonly referred to as the float process. More particularly, this invention relates to a process for attenuating the glass while supported on the molten metal to a thickness below the equilibrium thickness of the glass in such a manner so as to minimize distortion in the product glass.
In a float forming process, molten glass is delivered into a pool of molten metal and thereafter formed into a continuous ribbon or sheet of glass as disclosed, for example, in U.S. Pat. No. 710,357 of Heal; U.S. Pat. No. 789,911 of Hitchcock; U.S. Pat. Nos. 3,083,551 and 3,220,816 of Pilkington; and U.S. Pat. No. 3,843,346 of Edge et al. Under the competing forces of gravity and surface tension, the molten glass on the molten metal spreads outwardly to an equilibrium thickness of about 0.27 inches. In order to produce glass of thicknesses less than the equilibrium thickness, the prior art has resorted to various arrangements for stretching the glass while still in a viscous state on the pool of molten metal. The simplest stretching technique is that shown in U.S. Pat. No. 3,215,516 of Pilkington wherein stretching is done in the longitudinal direction (the direction of glass travel) only, wherein the stretching force is provided by the tractive means withdrawing the glass from the float chamber. In such an arrangement, the ribbon loses width as it becomes thinner. A common refinement of this arrangement is to employ lateral stretching means in order to reduce the loss of ribbon width as it is being stretched longitudinally. Typical of this latter approach is the process shown in U.S. Pat. No. 3,695,859 to Dickinson et al. Another approach is to maintain the ribbon of glass at essentially constant width by applying lateral tractive forces to edge portions of the ribbon as the ribbon is being attenuated in the longitudinal direction as exemplified in U.S. Pat. No. 3,843,346 of Edge et al.
Process perturbations originating with the attenuating process affect the topography of the glass ribbon in ways that degrade the optical quality of the product glass. The topography of float glass is characterized by two types of elongated features, thickness variations and corrugations, which extend generally parallel to the direction of glass travel, i.e., the longitudinal direction. These deviations from perfect flatness are, in effect, cylindrical lenses which distort light reflected from and/or transmitted through the product glass sheet. Analysis of the distortion patterns using optical scanners in a direction transverse to the direction that the glass traveled in the forming process reveals that the distortion patterns can be considered as consisting of randomly superimposed sinusoidal waves whose wavelengths vary over a wide range. It has also been found that the dominant component of the instrumentally measured signal corresponding to transmitted light occurs at rather well defined wavelengths that may range from about 1.2 to 1.4 inches (3.0 to 3.6 centimeters) for a "constant width" float forming process as in the Edge et al. patent cited above, to about 0.25 to 1.0 inches (0.6 to 2.5 centimeters) in the free-fall type of float forming as in the Pilkington patents cited above. Furthermore, these dominant wavelengths have been found to lie within a range to which the human eye is particularly sensitive for most applications.
Surface distortion in float glass is believed to arise from several categories of perturbations. First, inhomogeneities in the glass composition ("ream") not only cause nonuniformity of the refractive index of the glass but also can contribute to surface distortion. Second, thermal nonuniformity either in the molten glass entering the float forming chamber or within the chamber itself can contribute to surface distortion. Third, variations in the flow of molten glass from the melter to the forming chamber, either volume flow rate fluctuations or inequalities in the thickness of entering molten glass across the width of the ribbon of glass. Fourth, mechanical perturbations from contact of various members of the forming apparatus with the deformable glass ribbon. These include, for example, the stretching machines and side barriers as well as fluctuations in the speed with which the dimensionally stable ribbon is withdrawn from the forming chamber. These perturbations in the glass/tin system generate thickness variations or corrugations in the glass through a variety of mechanisms such as differential stretching, viscous folding, wrinkling, embossing, and membrane stress. While minimizing the causes of these perturbations is desirable, such an approach is limited because the perturbations cannot be completely eliminated, particularly in the case where less than equilibrium thickness glass is being produced. Therefore, this invention relates to diminishing the effects on distortion of these perturbations rather than eliminating the perturbations themselves.
As a newly formed ribbon of glass still in a softened condition progresses along the molten tin bath its topography is continually changing as perturbations introduce new defects into the ribbon and previously introduced defects are changed in shape. A defect may decrease in amplitude by means of viscous decay, or the wavelength of a distortion pattern may be altered by extensive or compressive stresses. It would be desirable if these distortion decaying mechanisms could be coordinated with the attenuating process so as to minimize the amount of distortion imparted to the glass when attenuated to below equilibrium thicknesses.
Some attempts have been made in the prior art to correlate the manner of attenuation to minimizing surface defects such as in U.S. Pat. Nos. 3,440,030 (Thompson et al.); 3,533,772 (Itakura et al.); and 3,520,672 (Greenler et al.), but it is now believed that none of these approaches fully meets the problem.
SUMMARY OF THE INVENTION
In the aforementioned copending application Ser. No. 137,329, it is disclosed that applying attenuating forces to a ribbon of glass in a float chamber in a specific sequence can substantially reduce the amount of apparent optical distortion in below equilibrium thickness glass. In one embodiment, the sequence may be summarized as passing the glass first through a relaxation zone, then a longitudinal and lateral stretching zone before the glass has cooled sufficiently to become dimensionally stable. Another embodiment is characterized by passing a glass ribbon through a longitudinal stretching zone and subsequently through a lateral stretching zone. In the longitudinal stretching zone, the glass is attenuated in the longitudinal direction as it is mechanically restrained from shrinking substantially in width so that the attenuation occurs largely by virtue of thickness reduction. A substantial portion, e.g., about 50 percent, of the overall thickness reduction is effected in the longitudinal stretching zone. It is believed that most of the surface defects are imparted to the glass during this longitudinal stretching. Immediately following the longitudinal stretching zone is a lateral stretching zone in which mechanical forces are applied to the ribbon to increase its width while reducing the ribbon to its final thickness. Stretching in the lateral stretching zone is primarily in the lateral direction, but tractive force applied to convey the ribbon in the longitudinal direction is usually sufficient to at least prevent longitudinal shrinking. Following the lateral stretching zone is a quiescent zone in which the glass ribbon is permitted to cool to a condition at which it may be withdrawn from the float chamber without damaging its surfaces.
This particular sequence of attenuating a glass ribbon is designed to minimize the creation of observed surface distortion in the glass produced. The improvements are based on the recognition that the optical power of glass surface distortion is a strong factor of the spatial frequency of the distortion features in accordance with the following relationship which relates optical power of a defect to its geometry:
P=khf.sup.2
where P is optical power, k is a constant, h is the height or amplitude of the surface defect, and f is the spatial frequency of the distortion pattern. It can be seen from this relationship that while amplitude and frequency both affect the optical power, the frequency is a second power factor whereas the amplitude is merely a linear factor. Therefore, the primary objective is to reduce the frequency of the distortion features. However, additional improvement due to amplitude reduction is also attained.
The improved attenuation technique is also based on the finding that longitudinal stretching is not only a major source of mechanical perturbations, but even more significantly, serves to increase the frequency of surface defects introduced into or pre-existing in the glass ribbon. Accordingly, the longitudinal stretching zone of the present method preferably is preceded by the relaxation zone so as to minimize the effects of any perturbations on the glass entering the longitudinal stretch zone. Furthermore, by carrying out most of the longitudinal stretching, which is accompanied by some of the most harmful perturbations, at a point where the ribbon is relatively narrow in width permits subsequent operations to be performed in the ribbon which reduce the amplitude and frequency of the surface distortion produced by the longitudinal stretching. More specifically, by widening the ribbon in the subsequent lateral stretching zone, the distortion patterns produced by the longitudinal stretching also become stretched in the lateral direction, thereby reducing their frequencies as well as their amplitudes.
The present invention is an improvement on the method of the previous application wherein the lateral attenuation step is assisted by cooling marginal edge portions of the glass ribbon. Cooling the edges permits greater lateral force to be applied to the glass ribbon in the lateral stretching zone, and transfers more of the longitudinal tractive force on the ribbon to the longitudinal stretching zone.
A variety of commercial configurations for forming flat glass on baths of molten metal may be adapted to practice the present invention, and several embodiments of such adaptations will be described herein.
THE DRAWINGS
FIG. 1 is a schematic cross-sectional side view of a preferred embodiment of the present invention employed in conjunction with a freefall molten glass delivery system.
FIG. 2 is a schematic plan view of the glass forming chamber of FIG. 1.
FIG. 3 is a schematic cross-sectional side view of an alternate glass forming chamber embodiment of the non-freefall type incorporating the features of the present invention.
FIG. 4 is a schematic plan view of the glass forming chamber of FIG. 3.
FIG. 5 is an enlarged plan view of edge cooling means that may be employed with the present invention.
FIG. 6 is a side view of the edge cooling means of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The embodiments depicted in FIGS. 1 and 2 relate to the type of float glass forming embodiments disclosed in U.S. Pat. Nos. 3,083,551 and 3,220,816 (Pilkington) which are in wide commercial use. Details of its construction and operation will be familiar to those of skill in the art. Generally, a mass of molten glass 10 from a melting furnace (not shown) is delivered by way of a canal 11 to a forming chamber 20. A tweel 14 extending through the roof 12 of the canal control the rate of delivery of the molten glass to the forming chamber. The chamber may comprise refractory floor 21, roof 22, and walls 23. A pool of molten metal 25 consists essentially of tin or an alloy thereof. The molten glass enters the forming chamber over a lip member 15 where it falls freely onto the molten metal to form a meniscus 26 which is permitted to spread laterally to the extent permitted by surface tension forces of the molten glass. The glass need not fall freely from the lip 15 but may be supported between the lip and the molten metal surface by a refractory member such as that shown in U.S. Pat. No. 4,055,407 (Heithoff et al.). This laterally spreading portion of the molten glass is designated zone A in FIG. 2 and constitutes the relaxation zone of the present invention. In zone A the glass is either at or above equilibrium thickness and is maintained at or above about 1600° F. (870° C.) up to a typical delivery temperature of about 2000° F. (1090° C.).
The principal function of zone A in the present invention is to maintain a relatively long residence time for the glass at this relatively high temperature range at which the glass will have a relatively low viscosity, which in turn encourages equilibrium of flow perturbations arising from delivery of the molten glass onto the pool of molten metal. This relatively long residence time is achieved by providing a relatively large volume of molten glass in zone A, such as by permitting the glass to spread laterally as shown in FIG. 2. Alternatively, the increased volume may be attained by enhancing the depth of the glass in zone A by means of side barriers or other means to urge the glass inwardly.
In FIG. 2, zone B represents a longitudinal stretching zone. The glass ribbon is at approximately the equilibrium thickness at the point where it is drawn into zone B. The longitudinal stretching of zone B is initiated at a location where the glass temperature is below 1700° F. (925° C.). Preferably, the longitudinal stretching is carried out at 1550° F. to 1650° F. (840° C. to 900° C.), optimally at about 1600° F. (870° C.). The temperature of the glass ribbon is permitted to fall as it passes through zone B but the temperature is controlled so that the temperature is not below 1500° F. (815° C.) when it enters the subsequent zone, zone C. Glass is drawn from zone A into zone B in the longitudinal direction whereby forces are applied to the glass which tend to cause the glass ribbon to be reduced in width and thickness. However, the reduction of width would be much more pronounced than the reduction in thickness if the longitudinal attenuation were permitted to proceed without restriction. This is disadvantageous since the ultimate object of attenuation is to reduce the glass thickness, and since a narrow glass ribbon is less useful commercially. Therefore, means are provided in zone B to restrict the narrowing of the ribbon and to force the attenuation in zone B to take place primarily at the expense of the thickness of the ribbon. The width-controlling means is preferably a set of rotating rolls 28 as shown in the art such as gas jets, blades or electromagnetic means. Preferably, the rolls 28 may be of the particular design shown in U.S. Pat. No. 3,929,444 (May et al.). A plurality of sets of rolls are provided in zone B so as to maintain the width of the ribbon substantially constant, each set consisting of a pair of rolls on opposite sides of the ribbon. The rolls engage the top surface of the edges of the ribbon, and their speeds of rotation are controlled so as to accelerate the longitudinal velocity of the ribbon as it passes through zone B. It is preferred that the rolls in zone B be angled outwardly slightly (about 5° to 10° from the direction of glass travel). In zone B the thickness of the glass is reduced from approximately the equilibrium thickness to a substantially reduced thickness typically on the order of about halfway or more toward the desired final thickness. This longitudinal attenuation is believed to induce a substantial amount of surface distortion in the glass, but that this distortion constitutes the majority of the distortion produced by the overall attenuation process.
Subsequently, the glass enters a lateral stretching zone, designated as zone C in FIG. 2, where the glass is brought to its final thickness. The glass in zone C may range in temperature from about 1600° F. (870° C.) to about 1450° F. (790° C.). Preferably, lateral stretching is carried out at glass temperature between 1450° F. (790° C.) and 1550° F. (840° C.), optimally at about 1500° F. In this final attenuation step the thickness reduction is achieved primarily by increasing the width of the ribbon. Lateral stretching forces are provided by means engaging the edges of the ribbon, such as sets of rolls 29 which may be the same design as rolls 28, or other known attenuating devices. The rolls 29 are angled so as to impart a lateral component of force to the glass ribbon. Longitudinal force is also applied to the glass in zone C by means of the rolls 29 as well as by the conveying means acting upon the formed ribbon beyond the exit of the forming chamber. The application of longitudinal force in zone C is desirable to assure that the final attenuation is accomplished through thickness reduction rather than by shortening of the longitudinal dimension. Some acceleration in the longitudinal direction may be imparted to the ribbon in zone C so as to stretch the ribbon in both the longitudinal and lateral directions, but the longitudinal stretching in zone C should be minor relative to that imparted to the glass in zone B.
The ratio of the final ribbon width to the ribbon width in zone B is directly proportional to the frequency of the optical power of the distortion. Therefore, it is desirable to maximize lateral attenuation in zone C. It has been found that a dominant distortion pattern due to thickness variation having a frequency ranging from about 0.70 to about 0.80 cycles per inch (0.28 to 0.32 cycles per centimeter) is created by longitudinal attenuation as in zone B. This frequency of optical distortion unfortunately happens to be in a region of frequencies which are highly sensitive to the human eye. The lateral attenuation in zone C advantageously reduces this frequency in accordance with the following relationship:
f.sub.2 =f.sub.1 ×W.sub.B /W.sub.D
where f 1 is the optical distortion frequency entering zone C, f 2 is the optical distortion frequency of the final glass product, W B is the width of the glass ribbon in zone B, and W D is the width of the glass ribbon in zone D. Accordingly, it is desirable to increase the ribbon width in the lateral attenuation zone C to at least 1.05 times the width of the ribbon in zone B, preferably by a factor of 1.1, and most preferably by a factor of 1.5 or higher. When feasible, it is desirable for the final ribbon width to exceed the maximum width of the glass in the relaxation zone.
After lateral attenuation, the glass ribbon enters zone D in FIG. 2 where it is permitted to cool without further attenuation to a temperature, typically about 1100° F. (595° C.), at which it is dimensionally stable and sufficiently hardened to be lifted from the pool of molten metal by means of lift-out rolls 31 at the exit lip 30 of the float chamber. Subsequently, the glass ribbon is typically conveyed on a roller conveyor through an annealing lehr.
In order to assist in establishing the thermal conditions disclosed above for zones B and C, it is preferred to employ barriers 35 and 36 submerged in the tin at the approximate boundaries between zones B and C and between zones C and D as shown in FIG. 2. The barriers may be of a known construction, such as the movable barriers disclosed in U.S. Pat. Nos. 3,930,829 (Sensi) and 4,099,952 (Schwenninger), and may be a two-piece construction as shown to facilitate insertion into the tin bath. The height of the barriers is less than the depth of the tin to avoid contacting the glass, but sufficient to retard the flow of tin in the longitudinal direction. By retarding the flow of tin from one zone to another, the desired thermal conditions can be established more readily in the respective zones. In order to help establish the desired thermal conditions in a portion of the glass ribbon, the temperature of the adjacent molten metal is usually maintained slightly lower, typically about 30° F. (17° C.) lower. The preferred thermal conditions for the longitudinal and transverse stretching zones are the subject matter of a copending U.S. patent application Ser. No. 307,814 entitled "Thermal Control in a Method of Bidirectionally Attenuating Glass in a Float Process" filed by R. J. Mouly on Oct. 2, 1981.
FIGS. 3 and 4 depict an adaptation of the present invention to a "constant width" type forming process as disclosed in U.S. Pat. No. 3,843,346 (Edge et al.). This embodiment differs from the embodiment of FIGS. 1 and 2 in that molten glass is delivered onto the molten metal in the forming chamber by means of a wide threshold and without free fall or unhindered lateral spread. Molten glass 40 is contained in a melting furnace 41 provided with a metering tweel 43 at the junction between the melting furnace and the forming chamber 50. A wide threshold 44 underlies the metering tweel 43 and supports the glass during its delivery into the forming chamber until it is supported by the molten metal 55. The forming chamber 50 may consist of a bottom 51, roof 52, and sidewalls 53 of conventional construction in the art. In accordance with the present invention, the glass ribbon 57 passes in sequence through four zones designated Q, R, S, and T in FIG. 4 and which respectively correspond in function to zones A, B, C, and D described above in connection with FIG. 2. Zone Q is the relaxation zone where, as previously described, the glass is maintained relatively undisturbed at a relatively high temperature in order to reduce the volumetric nonuniformities in the newly delivered layer of molten glass. Lateral spread in zone Q is restricted by means of side barriers 56 and 57.
Referring again to FIG. 4, the glass, after leaving relaxation zone Q, enters longitudinal stretching zone R wherein the ribbon is subjected to longitudinal attenuation to substantially reduce its thickness while maintaining substantially constant width by means of edge roll members 58 in the same manner described above in connection with zone B in FIG. 2. Likewise, subsequent lateral attenuation in a lateral stretching zone S, which includes outwardly angled edge roll means 59, is carried out in the same manner as in zone C described in connection with the FIG. 2 embodiment above. The temperature of the glass in zones Q, R and S is the same as that described above for zones A, B, and C respectively. Finally, the glass is permitted to cool, typically to a temperature of about 1100° F. (595° C.), in a cooling zone T after which the dimensionally stable ribbon of glass is lifted over exit lip 60 by means of liftout rolls 61.
A variation of the invention entails passing the glass from a relaxation zone such as A, or Q, as in the previously described embodiments into a combined longitudinal and lateral attenuation zone. In such a zone, the lateral and longitudinal attenuation may be carried out substantially simultaneously so that the ribbon of glass is increased in width to essentially its final width and is decreased in thickness to essentially its final thickness during passage therethrough. In such an embodiment, a substantial amount of longitudinal stretching would not be performed subsequent to the final lateral stretching.
Edge coolers 39 are shown in the lateral stretching zones of the embodiments of FIGS. 1 and 2 and FIGS. 3 and 4. The edge coolers serve to increase the viscosity of the edge portions of the glass ribbon, thereby permitting greater traction by the edge stretching rolls 29 or 59 on the glass ribbon, which is advantageous for imparting lateral stretching forces on the glass ribbon. Normally, edge stretching rolls pull a portion of the glass ribbon outwardly, and between the rolls the ribbon shrinks back partially to its original width, thereby producing a scalloped edge effect in a stretching zone. Cooling the edge portions of the glass ribbon reduces this scalloping, and as a result more uniform forces are applied to the ribbon. Another advantage of cooling the edges in the transverse stretching zone is that the relatively stiff edges transmit to the longitudinal stretching zone more of the longitudinal forces produced by the conveying means downstream from the exit of the forming chamber. Thus, the longitudinal tractive forces may serve to aid stretching in the longitudinal zone with a diminished effect on the ribbon in the transverse stretching zone. Preferably, the marginal edge portions of the ribbon are cooled to about 50° F.(28° C.) below the temperature of the central portion of the glass ribbon. Thus the edge portions typically may range from about 1400° F. to 1500° F. (760° C. to 820° C.) after being cooled in the transverse stretching zone.
Suitable edge cooling means are known in the art, an example of which is disclosed in U.S. Pat. No. 3,692,508. A preferred arrangement comprises a plurality of water-cooled members 39 shown in FIGS. 1-4, details of which are illustrated in FIGS. 5 and 6. Each cooler 39 includes a hairpin bent water conduit 65, to the end of which is welded a metal plate 66. Beneath the plate 66 is affixed a graphite block 67 which serves to prevent sticking of the glass ribbon 27 to the cooler in the event of accidental contact. The conduit 65 may be mounted in a side seal unit 68 which may be inserted into the customary access openings in the side walls 23.
Other variations and modifications employing features known in the art will be apparent to those of skill in the art and are within the scope and spirit of the invention as defined by the following claims. | Optical quality of float glass is improved by attenuating longitudinally prior to attenuating laterally and by providing cooled marginal edge portions of the glass ribbon during lateral attenuation. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates generally to roof ventilating systems, and particularly to roof ventilating systems for commercial and industrial buildings, that typically have substantially flat roofs.
A typical commercial roof includes a structural roof deck, covered by a vapor barrier. A layer of insulation is placed over the vapor barrier. An impermeable synthetic plastic roofing membrane is placed over the insulation. Water leaks from above the membrane may wet the insulation or water from inside the building may condense between the vapor barrier and the plastic roofing membrane and wet the insulation. Wet insulation has a reduced heat transfer resistance and can degrade.
Vents are used above the budding roof membrane to vent the space between the membrane and the vapor barrier. With effective roof venting, wet roofs can be dried over a period of time.
Another problem with membrane covered flat roofs is that a strong wind flowing across the membrane creates a suction that tends to lift the membrane up off of the roof structure. The present inventor has recognized that roof vents, if in air flow communication with the space beneath the membrane, transfer the suction force caused by the wind to an underside of the membrane and tends to pull the membrane down onto the roof structure in the vicinity of the vent.
SUMMARY OF THE INVENTION
The present invention provides a roof venting grid applied to a substantially flat roof that not only effectively dries wet insulation between a roof membrane and the vapor barrier, but also effectively holds down the roof membrane to the roof against high winds.
The present invention provides at least one lengthwise vapor path that extends substantially along a length of the roof and having a roof vent flow connected to the vapor path at each end of the vapor path. Furthermore the invention can have at least one widthwise vapor path that intersects the lengthwise vapor path and spans substantially the width of the roof and having a roof vent at either end of the widthwise vapor path.
Preferably, the invention provides a plurality of spaced apart lengthwise vapor paths and a plurality of spaced apart widthwise vapor paths, the widthwise vapor paths intersecting the lengthwise vapor paths and each of the lengthwise and widthwise vapor paths having a vent at opposite ends thereof, Also preferably, vents can also be located at the intersections of the lengthwise and widthwise vapor paths. Preferably, the vents at the intersections are turbine style vents.
According to another aspect, the vents are arranged around a perimeter of the building roof. Additional vents can be applied in corners of the building roof. The vents are all connected to a grid of vapor paths.
The vapor paths constitute open mesh fabric or mesh filter material. The open mesh fabric is fit on top of the insulation and below the upper membrane.
Numerous other advantages and features of the invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims, and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of a flat building roof;
FIG. 2 is a sectional view taken generally along line 2 - 2 of FIG. 1 ;
FIG. 3 is a sectional view taken generally along line 3 - 3 of FIG. 1 ;
DETAILED DESCRIPTION
While this invention is susceptible of embodiment in many different forms, there are shown in the drawing and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.
FIG. 1 schematically illustrates a building 18 having venting system 20 arranged on a flat building roof 26 . The roof 26 has a lengthwise dimension Y 1 of about 150 feet and a widthwise dimension X 1 of about 100 feet. The flat roof is substantially covered on a top side by a membrane 30 , typically EPDM material (ethylene propylene diene monomer), The venting system 20 illustrated includes twenty perimeter roof vents 32 and eight central turbine vents 38 . Each vent, 32 , 38 can be supported on a base mesh fabric 129 described below, although only two are shown tin FIG. 1 for simplicity.
Four transverse pathways 42 , 44 , 46 , 48 extend across the roof 20 . Each pathway includes a perimeter roof vent on each end and a pair of turbine vents 38 between the two roof vents. The remaining roof vents each are in communication with one of twelve tributary pathways 56 that communicate with either the first transverse pathway 42 or the fourth transverse pathway 48 . Interior connecting pathways 66 , 68 each connect to four turbine vents 38 that are substantially aligned. The pathways 56 , 42 , 44 , 46 , 48 , 66 and 68 form a grid of pathways that substantially cover the roof top in both the X and Y directions.
The vapor paths 56 , 42 , 44 , 46 , 48 , 66 and 68 are formed by open mesh fabric or filter material such as mesh material designated C06.03, at ⅞ inch thickness; 1 SB10, at 11/8 inch thickness; or 1 ECO, at 1 inch thickness, all available from Superior Fibers Inc. of Bremen, Ohio, US. The open mesh fabric is fit on top of the insulation and below the upper membrane 30 or below the vents 32 , 38 . The open mesh fabric allows air or vapor to pass horizontally through the fabric and vertically through the fabric. The vapor paths 56 , 42 , 44 , 46 , 48 , 66 and 68 preferably have a width between 9 and 12 inches wide, and more preferably 10 inches wide. The mesh fabric of the vapor paths can be secured to the insulation by insulation block fasteners and/or by adhesive or sealant.
Referring to FIG. 2 , the roof 26 may typically consist of an interior metal or wood building deck 100 , supported on roof purlins 102 which are part of a typical commercial building's frame structure. A near impermeable vapor barrier sheet 106 , covers the building deck 100 . Rigid fibrous or foam insulation boards or blocks 112 are provided between the barrier sheet 106 and the outer roof covering membrane 30 . Membrane 30 has an opening 114 in air flow communication with the vent 32 .
The vent 32 is more particularly described in U.S. Pat. No. 4,909,135, herein incorporated by reference. The vent 32 is fabricated in two component parts and, as shown, these parts include an upwardly extending open-ended tube 126 formed at its lower end with a radially outwardly extending annular flange 128 . The flange 128 is supported on one or more layers of a base mesh fabric 129 , which can be approximately 2 feet by 2 feet, and overlies the path 46 of mesh fabric. The flange 128 can be adhesively secured to the base mesh fabric 129 . The base mesh fabric 129 can be composed of one or more layers of mesh material K02.03, at 1½ inch thickness per layer and available from Superior Fibers Inc. of Bremen, Ohio, USA. The base mesh fabric is air permeable vertically and can be air permeable horizontally as well. The base mesh fabric must support the vent while at the same time not becoming too compressed by the weight of the vent to adversely affect its air permeability. The base mesh fabric can be secured to the insulation by block insulation fasters and/or by adhesive or sealant. The skirt 130 typically composed of cured EPDM wide cover tape adhered onto the membrane 30 around the vent and sealed by calk or sealant around its inside and outside perimeter to the tube 126 and to the membrane 30 . The tape of the skirt 130 can be applied in two strips and sealed along its seam, to form approximately a 2 foot by 2 foot skirt.
As shown in FIG. 2 , the tube structure 126 has an upwardly tapered peripheral wall portion 140 , terminating to leave a top opening (not shown) in the upper end of tube 126 . The lower end of tube 126 is open to a space 142 , provided above the insulation blocks 112 and occupied by the pathway 46 of mesh fabric and the base mesh fabric 129 .
A cap or hood, generally designated 152 , is provided for the upper end of the tube or stack 126 to prevent the entry of rain, snow and the like, and comprises a top wall 154 spaced above the top opening of the tube 126 , and has a downwardly divergent peripheral wall 156 extending generally parallel to wall portion 140 but overhanging the wall 140 .
When wind is present, an air stream traveling up between the walls 140 and 156 is converged by the fins within the hood 152 , such that its velocity is increased, and a venturi suction is created tending to pull an air current upwardly out of the tube 126 . The air pulled upwardly out of tube 126 is then moved outwardly, along the path “x”.
The vent 32 can alternately be constructed according to U.S. Pat. Nos. 6,234,198; 5,749,780; 4,593,504; or 3,984,947 which are all herein incorporated by reference. The roof vents in these patents incorporate a one way valve to allow air or vapor to exit the vent to ambient, but closes to prevent outside air from entering the vent 32 and flowing into the space between the membrane 30 and the barrier 106 .
FIG. 3 illustrates a typical turbine style vent 38 . The vent depicted can be constructed in accordance with U.S. Pat. Nos. 3,893,383 or 3,797,374, herein incorporated by reference. The vent 38 can also be constructed according to U.S. Pat. Nos. 3,066,596; 6,352,473 or 6,302,778 all herein incorporated by reference.
The vent 38 includes a turbine ventilator 164 mounted on an open-ended tube or stack 165 . The turbine ventilator 164 comprises a rotatable turbine 166 mounted on a shaft 174 . The shaft is stationary and supports the turbine 166 on a bearing assembly 176 . The bearing assembly is received in a socket or recessed opening on the lower side of a bonnet 178 . The bonnet 178 covers the top portions of the turbine 166 . The bonnet 178 is curved and approximates a segment of a sphere although it need not be precisely spherical in shape. It extends outwardly to a flat portion or encircling lip 180 . The lip 180 is preferably in a single plane which is perpendicular to the shaft 174 which supports the turbine 166 .
The bonnet 178 supports a number of ribs 184 . There are many ribs, and they are preferably arranged evenly around the bonnet 178 . They all extend downwardly to a ring 190 . Rotation of the turbine 166 , particularly the ribs, causes air or vapor to be drawn up the open ended tube 165 along the path x.
The stack 165 is installed onto the roof in identical fashion as the stack 126 shown in FIG. 2 and supported on one or more layers of base mesh fabric 129 that overlies the path 68 of mesh fabric.
Each of the vents 32 is installed in similar fashion to that shown in FIG. 2 and each of the vents 38 is installed in similar fashion to that shown in FIG. 3 . Each of the vents 32 , 38 is supported on, and in air flow communication with, one or more layers of a base mesh fabric 129 which is in air flow communication with a path of mesh fabric such as to exert an upward suction through the base mesh fabric 129 and the particular path depending on the wind condition on the roof.
The vapor paths 56 , 42 , 44 , 46 , 48 , 66 and 68 , allow air to be drawn though one or more of the turbine ventilators 38 and/or one or more of the vents 32 to dry out wet insulation and also to hold down the membrane 30 tightly to the insulation 112 . Because each path has two or more vents 32 , 38 in air flow communication with the pathways, any wind direction across the roof assists in drying large portions of the roof and assists in holding down the roof membrane.
Because of the interconnection of the paths 56 , 42 , 44 , 46 , 48 , 66 and 68 an overall drying of the insulation 112 can be achieved no matter the wind direction. Because of the interconnection of the paths 56 , 42 , 44 , 46 , 48 , 66 and 68 an overall hold down of the membrane 30 to the insulation 112 can be achieved no matter the wind direction.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. | A venting arrangement for a roof includes a plurality of venting stacks each having a first open base end open to an area on top of the roof insulation layer and below the roof outer membrane, the venting stacks arranged spaced apart around a perimeter of the roof. A venting path grid of air permeable material is arranged between the roof membrane and the insulation layer. The grid is in air flow communication with the first open base ends. Centrally located wind-driven turbine ventilators can also be in air flow communication to the grid. | 4 |
SUMMARY OF THE INVENTION
This invention relates to a new and distinct Canna cultivar which is outstanding because of its intense watermelon-pink bloom coloring, its dependable semi-dwarf growth habit, its tendency to shed bloom florets quickly, its hardy, robust rhizomes, its slow tendency to set seed, its resistance to leaf roller worms, and its reddish burgundy edged green foliage which has extremely sustained health and beauty throughout the season. This selection was made from a specially designed Canna hybridizing program with said hybrid cultivars being planted and grown in Grain Valley, Mo.
ORIGIN AND ASEXUAL REPRODUCTION
Asexual reproduction of this cultivar by dividing the rhizome was directed by me, such reproduction establishing that the plant does in fact maintain the characteristics described, in successive generations.
It should be noted that the plant was initially selected from a Canna planting being grown near Grain Valley, Mo. in a cultivated area and has since been reproduced by dividing the rhizome in the vicinity of Grain Valley, Mo. with the new and distinct characteristics stated herein, found to be maintained through successive generations as before recited.
Canna generalis is a group of tropical to sub-tropical herbaceous plants grown primarily for their rapid growth and vivid, flamboyant, summer blooms. They are grown in USDA zones 9-10 as a perennial and in USDA zones 3-8 as an annual. General growth habit includes an erect central (main) stalk with large tropical alternate leaves. This massive plant, usually 24"-96" in height, is topped by a colorful, inflorescent display. They are of easy cultivation in any fertile, moist soil, especially soils high in humus.
The cultivar of Canna generalis `Roblibwat` may further be described as having a number of distinctive characteristics which are enumerated in the succeeding specific description but broadly stated as comprising intense watermelon-pink bloom coloring, dependable semi-dwarf growth habit, tendency to shed bloom florets quickly, hardy, robust rhizomes, slow tendency to set seed, resistance to leaf roller worms, and reddish burgundy edged green foliage which has extremely sustained health and beauty throughout the season. The floral display has flowers of bright pink of (PMS#212). The bloom period begins at approximately 12 weeks after planting and continues until frost.
I have chosen to identify this new cultivar as Canna generalis `Roblibwat`. This cultivar is being marketed in the United States under the name of Liberty (tm) Watermelon.
BRIEF DESCRIPTION OF THE DRAWING
The accompanying photographs shows as nearly true as it is reasonably possible to make the same, in a color illustration of this character, typical flowers and leaves of the new variety. The photographic drawings illustrates the flower form, the novel and distinctive pink flowers color, and the forest green foliage.
In the photograph:
FIG. 1 illustrates the mature flower.
FIG. 2 illustrates the mature plant in mass.
DETAILED DESCRIPTION
In order to more specifically identify the cultivar, descriptive details are set forth hereinafter, along with related aspects of the plant which serve to distinguish the same, all colors being noted as compared with the Pantone Matching System (PMS). The measurements and colors were recorded from mature plants grown in the vicinity of Grain Valley, Mo., unless stated otherwise.
Parentage:
Seed parent.--Canna generalis hybrid "North Star Red" (not patented).
Pollen parent.--Unknown; open pollinated.
Propagation: Asexual reproduction by rhizome division started near Grain Valley, Mo.
Plant descriptions:
Inflorescence and reproductive parts.--The overall inflorescence is thrysoid (mixed) and is approximately 28 cm in length by 19 cm in width when mature. The terminal axis is indeterminate and the lateral axis are cymose and determinate. The large, zygomorphic, hermaphrodite flowers are borne terminally and more or less erect in a racemose inflorescence and are at anthesis together with one that is in bud. The flowers, borne on short pedicels occur in pairs forming a two-flowered cincinnus. Each flower is subtended by a bract. The outer whorl of the perianth consists of three free, imbricate sepals, the inner whorl of three basically united petals. There are typically three to five petaloid staminodes (showy portion of inflorescence) with the smaller fertile petaloid stamen and style visible at the center of the flower. Colors of "Petals" (showy portion composed of petaloid staminodes): PMS #212 bright pink. The perianth segments (petals and sepals) are also PMS #212. Due to the unusual composition of the reproductive parts, self pollination is more common in cannas than is cross pollination. The petaloid stamen and style are visible at the center of the flower. The stamen can be recognized by the presence of the single anther-cell along its upper margin. The pistil is made up of the stigma or tip, the petaloid style and a three locular ovary. The ovary is borne on a short pedicel and each loculus contains numerous anatropous ovules attached to an axile placenta. The rarely formed capsule has a warty pericarp that disintegrates at maturity to release the seeds.
Fragrance.--None detected.
Terminal axis.--Indeterminate.
Lateral axis.--Cymose and determinate.
Petaloid staminodes.--Pink (PMS #212) (bright pink).
Perianth segments.--PMS #Pink (212).
Bud at approximately one week prior to opening.--5.5 cm to 7.6 cm which is comprised of: Sepal -- 0.9 cm to 1.4 cm; Petal -- 0.9 cm to 1.4 cm; and Emerging stamenodes--Varying from 1.6 cm to 4.3 cm.
Color of reproductive parts:
Anther.--brown(PMS#438) to black at dehiscence.
Stigma.--Translucent cream.
Ovary.--medium green (PMS#369).
Stamen.--Pink blend, similar to inflorescence.
Style.--Pink blend similar to inflorescence.
Seeds.--At maturity are near black, and approximately 4 mm by 7mm in size.
Leaves: The alternate leaves are long ovate in shape and have pinnate veins and a dominate mid-rib. They are large, brad, simple, and entire with sheathing petioles. The average size of leaves at maturity is 53 cm in length by 28 cm in width. The dominate color in young leaves is light green (PMS #365) with burgundy (PMS#483) on both front and back edges and dark green (PMS #349) on both front and back at maturity.
Tubers (rhizomes): These tuberous rhizomes are cream & burgundy in color when immature, and transitions into a red-burgundy (PMS #484) at maturity. The rhizomes are covered by a papery scale like leaves. This paper layering is brown (PMS #439) with darker brown (PMS #440) veining. The average rhizome is 11 cm in length and 2.8 cm in width.
Roots: The fleshy roots arise from the internodes of the rhizomes and vary from 1.1 to 3.2 mm in diameter and are an average length of 32.1 cm.
Flowering time: The bloom period begins at approximately 12 weeks after planting (when planted at the recommended season and given reasonable care) and continues until frost. No pruning or pinching is required for optimum flowering performance. Spent blooms are shed quickly (approximately 30 hours after opening).
Diseases: No known unusual susceptibility to diseases noted to date.
Insects: No known unusual susceptibility to insects noted to date.
General Observations
Canna generalis `Roblibwat` with it's intense watermelon-pink bloom coloring, dependable semi-dwarf growth habit, tendency to shed bloom florets quickly, hardy, robust rhizomes, slow tendency to set seed, resistance to leaf roller worms, and reddish burgundy edged green foliage which has extremely sustained health and beauty throughout the season is striking in the landscape.
For the purpose of ornamental horticulture in our present living environments which include smaller yards and patio gardening, `Roblibwat` is ideal due to several characteristics. These plant characteristics are:
A. Colors of Inflorescence and leaves: The carrying power (visibility) of this cultivar's pink inflorescence contrast the rich green foliage for a striking landscape display.
B. Dwarf Stature: The hybridizer achieved the dwarf height (3 feet) of this canna hybrid by serial selection of new cultivars from his breeding program.
C. Compact Growth: Another goal was to achieve compact growth habit in a cultivar displaying the striking bright pink bloom. The achievement of this growth habit is primarily shown by two characteristics: The stem thickness to height ratio and the internode spacing.
For example: In Cannas `Roblibwat`, the stem thickness (11/2") to average height (36") ratio is 1 to 24. In the comparison plant, "Pink President", the stem thickness (11/2") to height (54") is 1 to 36. The internode spacing of "Pink President" is 81/2" and the internode spacing of `Roblibwat` is 63/4" which creates a more dense, compact presentation.
This dwarf and compact growth habit makes `Roblibwat` ideal for today's small garden and landscape designs and the patio/pot culture trend.
D. High Multiplication Rate: For commercial production, plant increase (multiplication rate) is very important. `Roblibwat` increases an average of 11 rhizomes in USDA zone 5 in one season (5 month period) and as high as 14 rhizomes in a USDA zone 9 within one year. This is ideal for production and marketing. Though there are a few cannas of either dwarf stature or adequate multiplication rate, or bright pink inflorescence against green leaves in today's market, applicant is not aware of any that meet all these criteria as completely as does `Roblibwat`.
E. Winter Storage: The storage capability of `Roblibwat` is another characteristic that renders this cultivar advantageous both to home gardeners and to commercial growers. The rhizomes are superior for storage because an average of 95% of stored rhizomes are viable after the winter storage period.
The winter storage capability of `Roblibwat` is very important for two reasons. Since cannas are only grown as perennials in USDA zones 9-10 and must be dug and stored in zones 3-8, a vast majority of home gardeners must routinely dig and store the rhizomes during the winter months. There is great variance as to the ability of different varieties to store successfully. `Roblibwat` survives winter storage with a high rate of success. Secondly, this storage ability of `Roblibwat` is of great advantage to commercial canna growers in USDA zones where the cannas must be dug and stored over winter months and a high degree of plant loss renders the product of no marketable value.
Comparison to Known Varieties
The cultivar may be compared with known varieties along the following lines.
Canna generalis `Pink President` is an appropriate choice for a comparison to Canna generalis `Roblibwat` because of the color combination of it's green foliage and coral pink bloom. Though `Pink President` has coral-pink blooms and green foliage, there are three distinguishing characteristics which have been improved upon in `Roblibwat`. These are (1) the pink color of `Roblibwat` has less coral or orange and would be considered by the observer as a more "true" pink. `Roblibwat` bloom PMS #212 to `Pink President` PMS #184. (2) `Roblibwat` is improved for today's demand for dwarf cannas as it is shorter than `Pink President`, i.e., `Roblibwat` is 3 feet compared to `Pink President's` height is 41/2feet. (3) `Roblibwat` maintains a "cleaner" overall presentation in the landscape than `Pink President`. This is due to (a) its inforescence shedding blooms before they are noticeably spent; and (b) the foliage remains fresher, cleaner, and more vigorous for a longer period of the season than that of `Pink President`, i.e., `Roblibwat` 4 months as compared to `Pink President` 3 months.
Canna generalis `North Star Red` is the seed parent of `Roblibwat`. The most significant difference between these two cultivars is their color. `North Star Red` is a red color as compared to the instant variety's color of pink. | A new and distinct cultivar of Canna generalis plant, substantially as described and illustrated herein, characterized particularly as to novelty by its intense watermelon -pink bloom coloring, dependable semi-dwarf growth habit, tendency to shed bloom florets quickly, hardy, robust rhizomes, slow tendency to set seed, resistance to leaf roller worms, and reddish burgundy edged green foliage which has extremely sustained health and beauty throughout the season providing a cultivar well suited as a garden or pot plant having no unusual susceptibility to the traditional Canna diseases and insects. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable
BACKGROUND
[0003] The present invention relates generally to concrete products, and more particularly, to a method of imprinting a visual and textural decorative pattern upon a concrete surface.
[0004] As is well known in the building and construction trade, concrete is extensively utilized as a building material for industrial, commercial and residential applications. Due to its durability, water resistance, and cost economy, concrete has gained wide spread use in flooring applications. As a result of wide spread use and popularity, the market is currently demanding concrete surfaces that have an improved aesthetic appeal with limited imperfections and irregularities. Common imperfections include blowholes, or minor lines and cracks that may form while the concrete is cured.
[0005] In order to meet this demand, the concrete trade has developed various coloring and surface finishing techniques designed to enhance the aesthetic appeal of concrete surfaces while masking imperfections and irregularities that may exist in the exposed surface areas. An example of such a finishing technique includes push broom finishes. Familiar push brooms such as are commonly used in sweeping floors are pulled across the drying concrete surface, leaving a pattern formed by the bristles as they pass across. Such brooms will ordinarily be found to possess threaded apertures into which a handle with perhaps one or more extensions may be fitted. The resultant bristled appearance provides a generic broom pattern across the concrete surface and serves to hide irregularities and imperfections that may exist thereupon. However, the bristled appearance left by the push brooms is often undesirable as it is not aesthetically pleasing and fails to provide any variations in depth, size, or diameter within the contours of the texture. Additionally, a push broom is increasingly unwieldly and it being the general experience that a push broom is unable to provide a consistent uniform finish across the surface.
[0006] Another known method of providing visual and textural effects to a concrete surface is the exposed aggregate method. The exposed aggregate method may be used to diminish the appearance of imperfections within a concrete surface while creating an aesthetically appealing application of concrete. Applicant has conducted extensive research and has developed a variety of methods improving upon the exposed aggregate method, including a variety of surface seeded exposed aggregate products and methods. In particular, several of these methods and products are described in Applicant's U.S. Pat. Nos. 4,748,788, 6,016,635, 6,033,146, and U.S. Patent Publication No. US 2007/02346, the contents of which are incorporated herein by reference.
[0007] In a particular surface seeded exposed method, subsequent to pouring the concrete, rock or gravel aggregate is scattered (i.e. broadcasted or seeded) over the top surface of the concrete and subsequently troweled into the same. As the concrete cures, the aggregate becomes adhered to the top surface of the concrete and is thus exposed. Although various sizes of aggregate can be broadcast over the top surface of the concrete in this method, such aggregate is normally of about three-eighths inch diameter or greater in size, and has sheared or jagged edges. The size and shape of the aggregate allows it to be worked into the top surface of the concrete and adequately adhered thereto. Applicant's techniques as described in the above-mentioned patents overcame many of the deficiencies of the prior art and produced improved surface finishes on surface seeded exposed aggregate concrete. In particular, the concrete resultant from practice of the above-mentioned patents exhibits an extremely flat exposed aggregate surface suitable for extremely high traffic flooring applications.
[0008] A requisite feature of surface seeded exposed aggregate is the addition of aggregates to the concrete surface. Therefore, there is a need in the art for applying a visual and textural decorative pattern upon a concrete surface capable of concealing imperfections or irregularities thereupon.
BRIEF SUMMARY
[0009] According to a preferred embodiment of the present invention, a method of imprinting a visual and textural decorative pattern to an uncured concrete surface is provided. Implementations of the present invention include a concrete product having a surface that models the fine, medium, and/or coarse grain textures of wood, lightly finished cut or honed stone, and the like. Further implementations of the present invention include a concrete product having a surface that incorporates a design pattern featuring any visual or textural pattern in accordance with a pattern imprinted upon a decorative finishing tool. Thus, implementations of the present invention may provide a concrete surface that precisely assimilates the characteristics and colors of wood or stone, including graining, fractures, and/or rock texture properties common in cut or honed stone implemented by utilizing a single finishing tool. Additionally, the unique design pattern serves to shield imperfections and irregularities existing on the concrete surface.
[0010] The method generally commences by preparing the concrete surface so that the decorative pattern may be implemented. In this regard, the initial step requires pouring a concrete mixture over the subgrade, with the concrete mixture defining an upper exposed surface when poured. Prior to the concrete mixture being poured thereover, the subgrade is preferably prepared to a desired grade. Such preparation preferably comprises compacting the subgrade to approximately 90% compaction. The compaction of the subgrade may be followed by the placement of a layer of sand thereupon, and the subsequent placement of reinforcement members (e.g., rebar) upon the layer of sand. When the layer of sand and reinforcement members are provided with the prepared subgrade, the concrete mixture is poured over the layer of sand and the reinforcement members such that the reinforcement members are encapsulated therewithin.
[0011] After the concrete mixture has been poured, the same is preferably screeded to a desired grade, which is followed by the step of finishing the exposed surface of the concrete mixture with a finishing tool, such as a vibrating metal bull float, to dispose a quantity of cement/fines paste derived from the concrete mixture at the exposed surface thereof. The finishing of the exposed surface via the vibrating metal bull float in this particular step also seals the exposed surface. It is contemplated that this initial finishing step may be completed through the use of either a vibrating magnesium bull float or a vibrating aluminum bull float. The Lievers Holland Company sells a preferred metal bull float under the trademark HAL 200.
[0012] It is contemplated that the decorative pattern may be implemented upon all types of concrete surfaces including surface seeded exposed aggregate. If the concrete surface is a surface seeded exposed aggregate then subsequent to the completion of the initial finishing step, a quantity of aggregate is broadcast upon the exposed surface of the concrete mixture. The aggregate may comprise silica sand, glass bead, coarse sand (e.g., Monterey Aquarium coarse sand), organic materials (e.g., sea shells), metals, or composite materials. The aggregate may comprise of particular materials specifically needed to create the sought after pattern. The quantity of aggregate is preferably broadcast over the exposed surface of the concrete mixture at an approximate rate of one pound per square foot of the concrete mixture. It is contemplated that the aggregate selected should carry certain requisite design features sought in the decorative patterns, such as size, color, or reflective qualities.
[0013] After being broadcast about the exposed surface of the concrete mixture, the quantity of aggregate is then preferably mixed into the quantity of cement/fines paste through the use of the vibrating metal bull float. As indicated above, the vibrating metal bull float used in the mixing step may comprise either a vibrating magnesium bull float or a vibrating aluminum bull float. Importantly, this mixing step is used to fully embed the quantity of aggregate into the quantity of cement/fines paste.
[0014] Subsequent to the initial preparation of the concrete surface, the exposed surface of the concrete mixture is finished with a decorative finishing tool thereby imprinting a decorative pattern on the exposed surface. In this regard, the predetermined pattern may be any visual or textural pattern such as wood grain, or light ground finishes found in cut or honed stone. A decorative finishing tool includes a blade having an impression of the decorative pattern formed thereupon. The blade is then troweled over the exposed surface of the concrete mixture to imprint the decorative pattern upon the exposed surface. The blade may have a custom designed template having protrusions such as rods, or indentations to uniquely form the decorative pattern. It is contemplated that protrusions, such as rods, may be rigidly attached to the blade through conventional means known in the art such as adhesives, welding, or fitting into grooves. It will be appreciated that the decorative pattern may have variations in depth, length, or size while still being formed by a single decorative finishing tool. Thereby, permitting a user to create such an aesthetically pleasing surface without the need for additional manpower.
[0015] Upon the implementation of the decorative pattern, the concrete surface is cured. In this regard, it is contemplated that a variety of finishing techniques may be employed specific to the type of concrete being utilized. Resultantly, a concrete surface having an aesthetically appealing visual and textural decorative pattern formed thereupon is provided. It will be appreciated that such a surface may be utilized in high traffic applications and retains the stability and durability features of concrete.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:
[0017] FIG. 1 is a perspective view illustrating stages of preparation of a decorative concrete product produced in accordance with an embodiment of the present invention;
[0018] FIG. 2 is a perspective view of a decorative finishing tool having a blade configured with a plurality of grooves for attaching the rods therein.
[0019] FIG. 2 a is a section view of the decorative finishing tool illustrating the grooves formed in the blade.
[0020] FIG. 3 is a perspective view of the rods configured to attach in the grooves of the blade of the decorative finishing tool; when attached the rods contact the exposed surface and imprint the visual and textural design pattern thereupon.
[0021] FIG. 4 is a perspective view of the rods rigidly attached to the grooves of the blade of the decorative finishing tool.
[0022] FIG. 5 is schematic diagram illustrating steps of a method for producing the concrete product in accordance with the present invention
DETAILED DESCRIPTION
[0023] Referring now to FIGS. 1-5 , pictorially and schematically illustrating the method transferring a visual and textural design to an uncured concrete surface of a concrete mixture utilizing a decorative finishing tool. The preferred method utilizes a decorative finishing tool to implement a pattern on the exposed surface of the concrete. As a result, the concrete is given an aesthetically pleasing appearance having various depths, sizes, diameters, and length within the contours of the texture thereby resembling natural patterns such as wood grain, or lightly finished cut or honed stone. Additionally, such contours and designs conceal imperfections and irregularities from the concrete surface.
[0024] The preferred method commences by preparing the concrete surface. In this regard, the initial step comprises preparing the subgrade 10 to a desired elevation and grade. The subgrade 10 layer of a pavement is, essentially, the native material underneath the pavement. It is also known as the “formation level”, which can be defined as the level at which excavation ceases and construction starts, therefore it is the lowest point of the pavement structure. Generally, a subgrade 10 requires some basic preparation for adaptation for construction purposes, this process is known as ‘subgrade formation’ or ‘reducing to level’. Such preparation preferably comprises compacting the subgrade 10 to approximately 90% compaction. Subsequent to being compacted, the subgrade 10 is preferably covered with a layer of clean, moist fill sand 12 which is preferably maintained at a minimum four inch thickness. Although the fill sand 12 is not absolutely necessary for the method of producing the decorative concrete surface of the present invention, it is highly desirable to control the hydration process of the concrete. In order to increase the resultant strength of the concrete and reduce subsequent cracking of the same, reinforcement members 14 such as wire mesh or rebar is/are positioned upon the layer of fill sand 12 .
[0025] With the reinforcement members 14 in place, a concrete mix or mixture 16 is poured over the layer of fill sand 12 and the reinforcement members 14 such that the reinforcement members 14 are encapsulated therewithin. The concrete mixture 16 is poured to approximately a three and one-half to four inch thickness. Although variations in the concrete mixture 16 are clearly contemplated, a preferred concrete mixture 16 comprises 70% sand and 30% three-eighth inch mean diameter aggregate combined with six sack cement (two thousand pounds per square inch) or seven sack cement (three thousand pounds per square inch). Dependent upon individual desires, various color mixtures can be added to the concrete mixture 16 . The color of the concrete mixture 16 may be specifically selected to complement the overall design being implemented in the decorative pattern. It is contemplated that a variety of colors to enhance the effects of the decorative pattern 24 may be employed by the present invention. In the present embodiment of the invention, the decorative pattern 24 implemented on the concrete structure is similar to wood grain. Therefore, the color of the cement mixture 16 may be reflective of wood, taking the color of brown or dark brown or a mixture of colors complementing the desired aesthetic appeal of the decorative pattern 24 . It is further contemplated that numerous colors may be employed at various stages of concrete preparation process to obtain varying shades of color if so desired.
[0026] After the concrete mixture 16 has been poured, the same is preferably screeded to a desired level plane or grade. Screeding is leveling and smoothing the top layer of the concrete mixture 16 , so the mixture 16 is the same height as the forms, or guides, that surround it. The screeding of the concrete mixture 16 results in the same defining a generally level or planar upper exposed surface 18 . Therefore in order to facilitate the implementation of the decorative pattern, subsequent to screeding, the exposed surface 18 of the concrete mixture 16 is surfaced or finished with a conventional finishing tool to dispose a quantity of cement/fines paste derived from the concrete mixture 16 at the exposed surface 18 thereof.
[0027] In the preferred embodiment, a vibrating metal bull float is utilized as the finishing tool. Such vibrating metal bull floats are known in the art and are characterized by possessing an extremely smooth or polished surface which, in addition to bringing up the appropriate amount of cement/fines paste for the subsequent manipulative steps of the present invention, also tends to seal the exposed surface 18 of the concrete mixture 16 . It is contemplated that this initial finishing step may be completed through the use of a conventional bull float. A bull float consists of a trowel blade produced from a specially designed hollow section alloy extrusion with a convex profiled sole. Typically, the blade angle is easily controlled to facilitate forward and backward movement by a blade pitch control. A bull float generally provides very accurate levels without the need for guiding rails. In the present embodiment, it is preferred that either a vibrating magnesium bull float or a vibrating aluminum bull float is utilized. A preferred metal bull float is sold under the trademark HAL 200 by the Lievers Holland company.
[0028] According to one aspect of the present invention, when the exposed surface is in the plastic state, fine sand 20 may be broadcast over the exposed surface 18 . The fine sand 20 may be of any given color or texture, as required by the decorative pattern 24 . Further, it is contemplated that various combinations of color, texture, or other characteristics of the fine sand 20 may be selected in order to complement the decorative pattern 24 .
[0029] It is contemplated that the present invention may be implemented upon a variety of concrete surfaces, including surface seeded exposed aggregate. Therefore, in an exemplary embodiment of the present invention, a quantity of aggregate 22 may also be broadcast upon the exposed surface 18 of the concrete mixture 16 . When the exposed surface 18 of the concrete mixture 16 is still plastic, small size exposed aggregate 22 is broadcast over the exposed surface 18 . It is preferred that aggregates 22 be clean, hard, strong particles free of absorbed chemicals or coatings of clay and other fine materials that could cause the deterioration of concrete. The selection of aggregates 22 may impact the aesthetic appearance of the decorative pattern. In this regard, the aggregates 22 are selected to complement the overall visual and textural characteristics of the design pattern.
[0030] As a result, a variety of techniques may be employed such that the aggregates 22 carry the desired visual and textural characteristics as required by the decorative pattern 24 . In an exemplary embodiment of the present invention, a benefaction process such as jigging or heavy media separation can be used to upgrade the quality of the aggregates 22 . In this regard, once processed, the aggregates 22 are handled and stored in a way that minimizes segregation and degradation and prevents contamination. Aggregates 22 not only impact the aesthetic characteristics of concrete but also influence freshly mixed and hardened properties, mixture proportions, and economy of the concrete.
[0031] It is preferred that the aggregate 22 comprise silica sand, glass bead, coarse sand (e.g., Monterey Aquarium coarse sand), organic materials (e.g., sea shells), metals, or composite materials. Additionally, it is preferred that any aggregate 22 employed in the present invention be characterized by having a mean average diameter size of approximately one-eighth inch diameter, and further be characterized by possessing a generally rounded external surface configuration. Such small size aggregate 22 is a substantial departure over prior art surface seeded exposed aggregates which typically comprise rock or gravel aggregate having average mean diameters of three-eighths of an inch or greater and are characterized by rough, jagged exterior surfaces. Typically, the aggregate 22 is broadcast over the exposed surface 18 of the concrete mixture 16 by use of square point shovels and is applied at a preferred rate of approximately one pound per square foot of the exposed surface 18 of the concrete mixture 16 . It is preferred that the aggregate 22 should not initially depress below the exposed surface 18 of the concrete mixture 16 , but rather should be broadcast solely to cover the same.
[0032] After being broadcast upon the exposed surface 18 of the concrete mixture 16 , the aggregate 22 is mixed or worked into the exposed surface 18 of the concrete mixture 16 , and more particularly is mixed into the quantity of cement/fines paste at the exposed surface 18 through the use of the above-described vibrating metal bull float. As indicated above, this vibrating metal bull float may comprise either a vibrating magnesium bull float or a vibrating aluminum bull float. This mixing of the aggregate 22 with the cement/fines paste at the exposed surface 18 derived during the previous vibrating metal bull float step is critical to the process of the present invention and insures that the aggregate 22 is fully embedded into the cement/fines paste, and thus thoroughly adhered or bonded to the exposed surface 18 of the concrete mixture 16 upon resultant curing. In order to maintain the design pattern, it is critical that the aggregate 22 is thoroughly bonded to the exposed surface 18 so that individual pieces of aggregate 22 are not dislodged and impacting the visual and textural effect of the decorative pattern.
[0033] Subsequent to the mixing of the aggregate 22 into the cement/fines paste at the exposed surface 18 of the concrete mixture 16 , the exposed surface 18 is finished with a decorative finishing tool 26 to implement the decorative pattern 24 upon the exposed surface 18 . A decorative finishing tool 26 is a concrete finishing tool that imprints a visual and textural decorative pattern 24 upon the exposed surface 18 of the concrete mixture 16 . It is contemplated that the decorative finishing tool 26 may be utilized upon any concrete surface. The decorative finishing tool 26 includes a blade 28 having first and second opposing sides 28 a , 28 b . The first opposing side 28 a is adapted to have a handle 30 or the like so that a user may easily navigate the decorative finishing tool 26 about the exposed surface 18 . It is contemplated that the first opposing side 28 a may carry an insert for employing conventional attachments known in the art such as broom handles and the like. It is further contemplated that the decorative finishing tool 26 may be adapted to work with existing trowels, floats, vibrating floats, and the like.
[0034] The second opposing side 28 b is smoothed or troweled over the exposed surface 18 and imprints the design pattern 24 thereupon. The second opposing side 28 b is adapted in accordance with the parameters of the design pattern 24 so that the when the decorative finishing tool 26 is troweled over the exposed surface 18 , the blade 28 creates the visual and textural design impressions upon the exposed surface 18 . It is contemplated that a predetermined template of the design pattern 24 may be formed upon the second opposing side 28 b . In a preferred embodiment, the second opposing side 28 b includes a plurality of rods 32 disposed about the second opposing side. The rods 32 are positioned in accordance to the decorative pattern 24 and configured to create the pattern 24 in the exposed surface 18 .
[0035] In the present embodiment, the decorative pattern 24 is that of wood grain. Generally, natural wood grain finishes include the alignment, texture and appearance of wood fibers. The appearance of natural wood grain varies depending on the sought after look. For example, one wood finish may include grains which runs in a single direction along the cut wood, a product of a straight growing tree. In a second example, a spiral wood grain where grain which develops as the trunk of the tree twists in development may be the sought after look. In order to capture these varying looks, the rods 32 may be constructed so that each rod 32 is varying in linearity, depth, length, and diameter to provide a naturally looking finish. As further illustrated by FIGS. 3 and 4 , the rods 32 may be positioned so that there are varying spaces 32 between them which further creates natural finishes found in wood grains.
[0036] It is contemplated that the rods 32 are rigidly affixed to the second opposing side 28 b so that the construction of the decorative finishing tool 26 can withstand the rigor of imprinting the decorative pattern 24 upon the exposed surface 18 . In this regard, the rods 32 may be affixed to the second opposing side 32 through conventional welding techniques or through the use of adhesives such as epoxy or the like. It is preferred that the second side 28 b is configured with grooves 34 that are adapted to rigidly clasp the rods 32 , as illustrated in FIGS. 2 , 2 a , and 4 . Therefore, as with the rods 32 , each groove 34 may be configured to have a varying length, size, depth, or width to capture the intended design. It is contemplated that conventional concrete-finishing tools such as floats or trowels may be adapted so that a decorative pattern 24 is formed upon conventional blades and configured to implement the decorative pattern 24 upon the exposed surface 18 . Prior art finishing tools do not provide such a capability and such a pattern would require utilizing numerous tools to create variations in depth, diameter, size and texture within the concrete. As such, the decorative finishing tool 26 provides the appearance of a multi troweled finish. Additionally, the decorative finishing tool 24 advantageously provides a consistent pattern 24 throughout its application over the entire exposed surface 18 .
[0037] Once the decorative pattern 24 has been troweled on the exposed surface 18 the concrete may be cured or finished. In certain concrete surfaces a variety of finishing techniques are employed to enhance the stability and durability of the surface. It is contemplated, that the implemented design retains its appearance during the employment of a finishing technique. A common finishing technique utilized with exposed aggregate concrete is the application of a chemical surface retarder. A chemical surface retarder is sprayed upon the exposed surface 18 to uniformly cover the same. The chemical retarder slows down the hydration process of the concrete mixture 16 . The chemical retarder does not affect the visual or textural appeal of the decorative pattern 24 . The application of the surface retarder to the exposed surface 18 is followed by the step of finishing the exposed surface 18 of the concrete mixture 16 with a conventional finishing tool or a spray to massage the surface retarder into the cement/fines paste having the aggregate 22 mixed therein. This finishing step preferably results in the penetration of the surface retarder into the cement/fines paste a distance of at least approximately three-eighths of an inch which, due to the relatively small size the aggregate 22 therein, is below the maximum depth of the aggregate 22 . The chemical retarder slows down the hydration process of the concrete mixture 16 . Advantageously, this particular finishing step conducted subsequent to the application of the surface retarder to the exposed surface 18 of the concrete mixture 16 eliminates hard spots in the resultant concrete by facilitating a full mix of the retarder and cement/fines paste.
[0038] Subsequent to the surface retarder being massaged into the cement/fines paste, a vapor barrier is preferably formed on the exposed surface 18 of the concrete mixture 16 . In the preferred embodiment, the formation of the vapor barrier is facilitated by the application of a liquid chemical evaporation reducer to the exposed surface 18 of the concrete mixture 16 . A preferred evaporation reducer is sold under the trademark CONFILM by the Concrete Tie company of Compton, Calif. An alternative vapor barrier may be formed by covering the exposed surface 18 with four or six mill visqueen. The vapor barrier is maintained upon the exposed surface 18 of the concrete mixture 16 for a prescribed period of time, which may range from approximately two to twenty-four hours. The vapor barrier does not affect the visual or textural characteristics of the decorative pattern 24 upon the exposed surface 18 .
[0039] After the vapor barrier has remained upon the exposed surface 18 for a prescribed period of time, the exposed surface 18 of the concrete mixture 16 is washed with water to remove any surface films therefrom. In this washing procedure, it is additionally preferable to lightly bristle brush the exposed surface 18 wherein preferably no more than about 5% of the aggregate 22 is dislodged and removed therefrom. The extremely low percentage (i.e., less than 5%) removal of the aggregate 22 from the exposed surface 18 evidences the extremely strong adherence of the aggregate 22 to the exposed surface 18 of the concrete mixture 16 . It is preferred that brushing the exposed surface 18 is done in a manner to minimize any deviation from the intended visual appeal of the decorative pattern 24 .
[0040] As a result of the washing step, the full mixture of the retarder and cement/fines paste accomplished through the use of a conventional finishing tool known in the art, such as a trowel or float, subsequent to the application of the surface retarder to the exposed surface 18 of the concrete mixture 16 significantly aides in the elimination of perimeter wear-down and excessive dislodgement and loss of the aggregate 22 during this initial washing step. Which resultantly facilitates the preservation of the decorative pattern 24 upon the exposed surface 18 . Additionally, the application of the liquid evaporation reducer to the exposed surface 18 which prevents hydration of the concrete mixture 16 and reduces the rate of evaporation of moisture therefrom increases the ease at which excess cement/fines paste and residual surface retarder are washed from the exposed surface 18 during this initial washing step. In this regard, the aggregate 22 embedded within the decorative pattern 24 is minimally affected.
[0041] Subsequent to washing, the concrete mixture 16 is cured with water only as opposed to chemical curing agents to avoid any staining of the same or interference with the visual or textural aesthetics of the design pattern, with such water curing typically being facilitated through the use of a conventional fogger or soaker hose. After a prescribed period of time (e.g., 30 days after initiating the curing process) any surface residue present on the exposed surface 18 is removed by conventional power washing with a 90% steam and 10% muriatic acid mixture which is applied by a power washer via a high pressure nozzle. It is contemplated that conventional power washing of the concrete does not detract from the decorative pattern 24 formed upon the exposed surface 18 .
[0042] The resultant concrete exhibits an aesthetically appealing surface that conceals imperfections upon the surface and is advantageously suitable for high pedestrian traffic flooring applications. Additionally, the surface color and texture may be such that it approximates conventional flooring surfaces such as stone or wood. This resemblance can further be accentuated by saw cutting the concrete surface into rectangular grids to give the appearance that the individual rectangular squares of the grid were laid in a manner analogous to stone or wood flooring. Thus, the present invention comprises a significant improvement in the art by providing a surface seeded exposed aggregate concrete having a decorative pattern formed thereupon and possesses a surface texture and color having improved aesthetics over the prior art.
[0043] Additional modifications and improvements of the present invention may also be apparent to those of ordinary skill in the art. Thus, the particular combination of parts and steps described and illustrated herein is intended to represent only one embodiment of the present invention, and is not intended to serve as limitations of alternative devices and methods within the spirit and scope of the invention. | A decorative concrete product and method of making the same is provided. The concrete surface carries a unique textural and visual decorative pattern that is troweled over the uncured surface. The decorative pattern strategically conceals any imperfections in the concrete surface. A decorative finishing tool is utilized to create a unique and consistent pattern throughout the exposed surface of the concrete. Unique visual patterns may include any aesthetic design including wood grain, or lightly finished honed or cut stone. The decorative finishing tool may be configured so that varying textures and contours may consistently be imprinted throughout the concrete. Advantageously, the cured concrete retains the durability of a concrete surface while carrying a visually and texturally appealing appearance. | 4 |
BACKGROUND OF THE INVENTION
The invention relates to reciprocating internal combustion engines fueled by turbine fuels, and more particularly of the type that operates on a combined stratified, spark-assisted compression ignition and torch-assisted compression ignition processes utilized with aviation turbine fuels.
Competition in the world for fossil fuels among various transportation segments will continue to grow and those fuels that are manufactured in relatively low quantities are becoming more expensive and vulnerable to critical shortages and environmental demands. Among aviation fuels, gasolines have proven to be the most vulnerable and the additional environmental constraints such as total elimination of lead as an anti-detonant additive are further threatening the future availability of high octane aviation gas. Automotive gasolines may provide a practical alternative to the low performance range of piston aircraft engines. However, high performance and high altitude piston aircraft engines must continue to depend upon high octane aviation gasolines, or an alternative fuel. There are large worldwide supplies of turbine fuels due to airline and military requirements which will be maintained in the foreseeable future. Such fuels offer plentiful supplies with existing distribution systems and are devoid of liability burdens associated with automotive gasolines used in aircraft.
Stratified charge engines have been in existence for over 50 years, as exemplified by the Ricardo Pat. No. 2,191,042. These engines in isolated cases have successfuly operated with turbine fuels, however, they have been used in ground transportation applications. Both stratified and diesel turbine fuel adaptations of the past represent low specific output engines with limited regard for economic considerations and their principal objectives being to meet particular emission standards and multi-fuel capabilities. All of the prior developments in these areas have failed to produce a light and efficient high specific output engine capable of operating on turbine fuels.
A number of prior art patents use a pilot fuel spray which is ignited by an electrical spark or surface heated element to establish a flame or stream of hot gases which in turn is used to ignite a main fuel charge such as typified by Hoffman, U.S. Pat. No. 2,902,011 and Loyd, U.S. Pat. No. 4,414,940.
The concept of shaping the piston crown to promote swirl as the piston approaches top dead center is generally taught in the patent to Yamakawa, U.S. Pat. No. 4,166,436, and applicant's recently granted U.S. Pat. No. 4,594,976.
SUMMARY OF THE INVENTION
The present invention is directed to a hybrid or convertible internal combustion engine process which utilizes a stratified charge Otto cycle during starting, idle and low specific output operations, while gradually converting to a spark or glow plug assisted or a non-assisted compression ignition (diesel) mode as specific engine outputs increase. Transitions from one mode of operation to another, and degree of said transitions depend on fuels adopted, combustion chamber compression ratios, degree of super or turbocharging, coolant temperatures, engine specific outputs, inlet air temperatures, relative prechamber/main chamber combustion volumes, prechamber discharge orifice proportions and other variables. By control of said variables the present invention combustion process may be adapted to a wide range of applications.
The precombustion chamber located in the cylinder head includes a pilot fuel injector and a source of ignition. The prechamber is connected to the main combustion chamber by means of a passage or orifice located in such a manner as to induce a swirling airflow within the prechamber during the compression stroke. During that swirling airflow, and prior to the piston reaching the top dead center, the pilot fuel injector discharges fuel into the precombustion chamber, the mixed fuel and air are then ignited by the ignition source which initiates the combustion process.
During the starting, idle or low specific power output operations the prechamber combustion process remains largely or completely dependent on the stratified charge principles described above. However, as power increases, with higher chamber surface temperatures, and higher fuel inputs, the ignition source dependencies change and the process approaches a spark or glow plug assisted or a non-assisted compression ignition (diesel) mode.
As combustion develops in the prechamber, temperatures and pressures increase, and the internal swirl flow is reversed as combustion gases leave the prechamber through the connecting passage and flow into the main chamber. The burning gases flowing through the connecting passage thus impart or enhance the swirling flow of air within said recess or bowl. As the piston approaches its top dead center position, the clearances between the piston top and cylinder head diminish thus forcing the squish air to flow towards the piston recess along the surface of the piston.
The hot gases, unburned fuel and/or torch flames emanating from the prechamber further increase the temperature and pressures within the piston recess and upon main fuel injector discharge of fuel, said prechamber efflux promotes mixing of fuel with the swirling air, accelerates precombustion chemical activities and eventually ignites or assists in the ignition of the main chamber swirling mixtures. Here again, at low specific power outputs, ignition of main chamber mixtures are dependent on prechamber efflux gases and/or torch flame. However, as specific outputs increase, said dependency decreases and the process gradually approaches a non-assisted compression ignition mode of operation.
Location of main combustion chamber piston recess substantially under the exhaust valve reduces heat losses from the main combustion volume, and complements confinement of main chamber gases within heated or insulated boundaries as indicated by combustion and precombustion enhancement provisions. Insulating inserts or liners with or without catalytic properties over prechamber, main chamber and associated ramps may be adopted depending on application, to enhance precombustion chemical reactions, reduce combustion delay periods, control formation of deposits, reduce heat losses to engine coolants and lubricating oils, avoid boundary quenching and reduce ablation or gas erosion due to excessive heating of light alloy elements.
Pilot and main fuel injections timings may be concurrent or staged depending again on application parameters such as maximum specific outputs, engine speeds, fuels used and justifiable complexity of associated fuel injection systems.
Processes noted above allow the adoption of a relatively low compression ratio engine capable of producing high specific power outputs using turbine fuels or other fuels devoid of strict octane and cetane specific ratings, ideally suited for aircraft use and capable at operation of relatively high fuel/air ratios (when compared with standard stratified or compression ignition engines), thus reducing engine size, weight, installation volume, manufacturing cost and reducing induction air supercharging or turbocharging demands.
Adoption of spark or glow plug ignition assistance provisions, hot insulated combustion chamber liners and prechamber torch ignition of main combustion chamber reduces combustion delay periods thus limiting the amounts of raw fuel present at point of ignition, and in turn yielding conservative combustion pressure rise rates and peak pressures. These conditions control knock and reduce engine structural demands.
It is therefore the principal object of the present invention to provide an aircraft reciprocating piston engine capable of operating on turbine fuels.
Another object of the invention is to provide a reciprocating piston engine other than aircraft applications capable of operating with fuels devoid of octane ratings or cetane specific rating requirements.
Another object of the present invention is to provide a lightweight high specific output piston engine capable of operating with turbine fuels at relatively low compression ratios and relatively high fuel/air ratios.
A further object of the present invention is to provide an improved piston engine capable of operation on spark-ignited stratified combustion at low specific output over a wide range of fuel/air ratios and transitioning to a spark-assisted compression ignition or non-assisted compression ignition mode at higher specific outputs but capable of efficient operation at fuel/air ratios higher than normally practical with traditional non-assisted compression ignition engines.
Another object of the present invention is to provide an improved piston engine with low specific air consumption and throttleless operation thereby extending the altitude capabilities of current technology turbochargers.
Further objects and features of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings which form a part of this specification.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the engine of the present invention with the cylinder and head not shown in detail, to better view the combustion chambers;
FIG. 1A is a perspective view of the piston only showing a modified form of the main combustion chambers;
FIG. 2 is a top plan view of the piston with the precombustion chamber and its related components shown in dotted line;
FIG. 3 is a sectional view taken along line 3--3 of FIG. 2, illustrating the cylinder, cylinder head and piston in the top dead center position;
FIG. 4 is a sectional view taken along lines 4--4 of FIG. 5;
FIG. 4A is a similar sectional view of a modified form of precombustion chamber;
FIG. 5 is a sectional view through the precombustion chamber and cylinder;
FIG. 5A is a similar sectional view of a modified form of precombustion chamber;
FIG. 6 is a symbolic illustration of various air, fuel and gas flows during compression, at top dead center and at the initiation of th expansion stroke; and
FIG. 7 is a perspective view of the FIG. 1A piston top surface illustrating the various air and gas flow paths at the top dead center position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The hybrid engine of the present invention is generally described by reference numeral 10, as seen in FIG. 1. While the engine is only shown with a single cylinder 15, it is capable of utilizing any number of cylinders in any cylinder arrangement pattern. Various parts of the engine are conventional and well-known in the art and are therefore not described in detail.
The engine includes a piston 11, reciprocally mounted within a cylinder 15, closed at its upper end by a cylinder head 34, as best seen in FIGS. 3, 4 and 5. Located in the cylinder head 34 are a pair of conventional inlet and exhaust valves 12 and 13, respectively, located in inlet and exhaust passages 14 and 32 (shown in dotted line in FIG. 1). Passing through the inner surface 36 of cylinder head 34 is a main fuel injector 25, as best seen in FIGS. 2, 3 and 4. Also located in cylinder head 34 is a precombustion chamber or prechamber 19 which connects with the interior of the cylinder through a lineal passage 20, as best seen in FIGS. 2 and 4. The cross sectional area of passage 20 must be sufficiently small to create a high enough velocity in chamber 19 during the compression stroke to maintain a high rate of fuel emulsification, yet not too strong to blow off the fire kernel. Also located in precombustion chamber 19 is a spark plug 24 and pilot fuel injector 22. Both the pilot injector 22 and the main injector 25 are controlled by conventional means not shown in the drawings. Chamber 19 is substantially spherical, or a figure of revolution, with lineal passage 20 tangentially intersecting chamber 19 so that gases entering through passage 20 create a swirling flow.
Located in the top surface 38 of the piston is main combustion chamber recess or bowl 16 which may be slightly offset from the center of the piston. Lateral passage 20 is tangentially aligned with recess 16 when the piston 11 is close to its top dead center position, as illustrated in FIGS. 2, 4, 5 and 7.
FIG. 1A illustrates a slightly modified piston 11 with a tangential ramp 17 entering recess 16' which is longitudinally aligned with lineal passage 20 when piston 11' is in its top dead center position.
At the top dead center position, also referred to as TDC, the clearance between the top surface of the piston 38 and the inner surface 36 of the head is reduced to practical mechanical limits so that substantially all of the available combustion volume at TDC is basically precombustion chamber 19, lateral passage 20, main combustion chamber or recess 16 and ramp 17 when applicable.
FIGS. 4 and 5 illustrate a slightly modified form of the invention wherein the precombustion chamber 19 is provided with a liner 40. The liner is temperature-insulated material intended to raise the surface temperature for the purpose of promoting combustion. Various types of liner materials can be used which not only affect the chemical process of combustion, but also accelerate combustion, reduce combustion delays, accelerate evaporation of the fuel impinging on the liner surfaces, as well as control combustion deposits. The liner material may be an alloy incorporating elements such as nickel-chromium and copper. The liner material can also be a ceramic compound with elements such as zirconium which promote combustion via catalytic enhancement.
FIGS. 4A and 5A illustrate a modified form of precombustion chamber 19' which has multiple lineal passages 20' connecting to the main combustion chamber which provides a different flame discharge pattern.
DESCRIPTION OF THE OPERATION
The engine 10 operates in accordance with a four-stroke cycle. On the first stroke, piston 11 moves downward with intake valve 12 open and exhaust valve 13 closed. The downward movement of piston 11 cases air to flow through the normally unthrottled or unrestricted intake passage 14 into the cylinder 15. Airflow into the cylinder is promoted by atmospheric pressure or conventional supercharging pressures acting on the induction air entering passage 14. On the second stroke of the cycle, air inlet valve 12 is closed, exhaust valve 13 remains closed, and piston 11 moves upward to compress the air in cylinder 15, as illustrated by the COMPRESSION STROKE in FIG. 6. As the piston 11 moves upward during the compression stroke, compression air is forced through lineal passage 20 into precombustion chamber 19, introducing a swirling airflow pattern as indicated by the arrows in FIG. 6.
As piston 11 approaches its top dead center position, pilot fuel injector 22 injects a spray 23 into the swirling compressed gases, as illustrated in the TDC position of FIG. 6. The optimum timing at which pilot fuel injection occurs would vary for each application, depending upon the operating conditions and the particular engine size. The amount of fuel injected during each individual cycle may be constant or may vary depending upon different applications. Occurring at substantially the same time as pilot injection, igniter spark plug 24 is caused to fire thereby beginning ignition. Other ignition sources such as electrically heated glow plugs, not shown, could also be utilized during engine start-up and initial warm-up, while the glow plug would remain heated by combustion heat with or without the assistance from an electrical source. As the pilot fuel spray begins to burn, the expansion of the burning gases causes a reversal in flow direction, as indicated by arrows 27 in FIG. 6. The burning gases or torch flame 27 are now directed tangentially into main combustion recess 16 causing a swirling action of the gases, as indicated by arrows 28 in FIG. 7.
As the piston 11 approaches its top dead center position, the clearance between the top surface 38 of the piston and the inner surface 36 of the head rapidly diminishes in an area generally referred to as the "squish volume". The gases in this rapidly decreasing volume will flow into main combustion chamber 16. This last-mentioned flow likewise induces a swirling flow and mixing action within recess 16. The squish volume gases entering recess 16 are caused to intersect and mix with the burning gases 27 flowing from the prechamber 19 while they together flow into the main combustion recess 16.
A main fuel spray 29 is injected into the main combustion recess 16 through main fuel injector 25. The timing of main fuel injection may be concurrent with the pilot fuel injection on engines of low specific output or low compression. However, generally, main fuel injection will be timed after pilot injection, well after prechamber combustion is under way. Delayed main fuel injection allows the fuel to burn with minimum delay within the strong swirling preconditioned air in piston recess 16, practically as it emerges from injector 25. Since no fuel is allowed to accumulate within recess 16, the combustion process that follows is smooth and conducive to low peak combustion gas pressures.
Under certain conditions of low power or with a cold engine, pilot and main fuel injection sprays may contact the surfaces of the prechamber 19 and recess 16, thus introducing a combustion delay factor, and during these circumstances, burning of deposited fuels will largely depend on fuel evaporation rates from those surfaces. Both pilot and main injectors 22 and 25 inject sprays directly into combustion volumes 19 and 16, and thus provide a wide range of fuel/air ratios.
The modified piston 11' of FIG. 1A directs the burning gases 27 down an entry ramp 17 for a similar tangential entry into main chamber 16', as seen in FIG. 7.
From the foregoing statements, summary and descriptions in accordance with the present invention, it is understood that the same are not limited thereto, but are susceptible to various changes and modifications as known to those skilled in the art, and we therefore do not wish to be limited to the details shown and described herein, but intend to cover all such changes and modifications which would be encompassed by the scope of the appended claims. | A low compression reciprocating internal combustion piston engine with a prechamber in the head connected to a main combustion chamber in the piston, the prechamber having an igniter, a pilot fuel injector and connecting lineal passage; the main chamber including a fuel injector for mixing the prechamber gases with the gases being compressed in the cylinder. The engine is a hybrid having transitional combustion modes from spark-ignited stratified charge mode at low power, to a spark-assisted compression ignition at higher power loads, and a strictly compression ignition mode at maximum power loads. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the US National Stage of International Application No. PCT/EP2010/065646 filed Oct. 18, 2010 and claims the benefit thereof. The International Application claims the benefits of European application No. 10172377.3 filed Aug. 10, 2010, both of the applications are incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to rotor blade element, especially a wind turbine rotor blade element, a wind turbine rotor blade, a wind turbine and a method for improving the efficiency of a wind turbine rotor blade.
BACKGROUND OF THE INVENTION
[0003] Blade elements provided for improving the efficiency and for changing the aerodynamic profile of a wind turbine rotor blade and such elements mounted to a trailing edge of a blade are well known from patent literature. Example hereof are EP 1 314 885 B, EP 2 195 525 A, WO 2009/026929 A1, EP 2 031 242 A1, US 2010/143151 A, EP 1 775 464 A and US 5,328,329 A. The elementary features like normal elastic trailing edge or serrated edge are also much known from the cited literature.
[0004] In US 2010/0143151 A1 a wind turbine blade is disclosed, which includes a permeable flap extending from a trailing edge of the blade. The flap can be retrofit to existing blades and may flush with the outer surface of the blade.
[0005] In U.S. Pat. No. 5,328,329 a width extender is provided, which is used to modify existing fan blades in order to enable them to rotate at slower speed thereby reducing the noise associated with them while at the same time maintaining proper work efficiency. The width extender is fixably connected along the trailing edge of an existing fan blade by, for example, adhesive bonding.
[0006] In EP 2 195 525 A, WO 2009/026929 A1 and EP 2 031 242 A1 a blade element for mounting on a wind turbine blade is provided. The blade element has a shape so that, by mounting in a first longitudinal part of the wind turbine blade, it changes the profile of the first longitudinal part from the first airfoil profile with an essentially pointed trailing edge and a first chord length to a changed airfoil profile with a blunt trailing edge. The changed airfoil profile is a truncated profile of an imaginary airfoil profile with an essentially pointed trailing edge and a second chord length which is larger than the first chord length.
[0007] In EP 1 775 464 A2 a wind turbine with a blade rotor which reduces noise by the inclusion of a set of flexible bristles is disclosed. The set of flexible bristles is aligned in at least one row on the trailing edge of the aerodynamic profile of the blade and protrudes over it.
[0008] In EP 1 314 885 B1 a method and an apparatus for improving the efficiency of a wind turbine rotor are disclosed. The wind turbine rotor comprises a serrated panel connected to each wind turbine rotor blade, an upper and a lower surface on each panel, a plurality of span-wise, periodic indentations on each panel, means for connecting the serrated panel to a trailing edge on each of the wind turbine rotor blades of the wind turbine rotor such that the serrated panel extends from the trailing edge into airflow behind the trailing edge. The serrations on each wind turbine rotor blade have an angle different from 0° relative to a mounting surface on each of the wind turbine rotor blades. The serrations on each of the serrated panels have a given stiffness allowing for an angle of the serrations to change passively in response to speed and angle of the airflow at the trailing edge of each of the wind turbine rotor blades due to flexing of the serrations and the serrated panel.
SUMMARY OF THE INVENTION
[0009] It is a first objective of the present invention to provide a rotor blade element which improves the efficiency of a wind turbine rotor blade and reduces noise during operation of a wind turbine rotor blade. It is a second objective of the present invention to provide a wind turbine rotor blade with an improved efficiency and reduced noise during operation. A third objective is to provide a wind turbine with improved efficiency and reduced noise during operation. It is a forth objective of the present invention to provide a method for improving the efficiency of a wind turbine rotor blade.
[0010] The objectives are solved by the independent claims. The depending claims define further developments of the invention. All described features are advantageous individually or in any combination with each other.
[0011] The inventive rotor blade element is adapted for mounting it on a wind turbine rotor blade. The wind turbine rotor blade comprises a trailing edge, a suction side and a pressure side. The blade element comprises a trailing edge, a first surface and a second surface. The first surface forms a pressure side surface portion. The second surface comprises a suction side surface portion and a contact surface. Preferably, the contact surface is adapted for connecting the rotor blade element to the pressure side of the rotor blade.
[0012] The inventive rotor blade element has the advantage that it is easy to fit to a rotor blade. Furthermore, it may preferably have a form that makes it a natural prolongation of a trailing surface or trailing edge of the rotor blade. The rotor blade may comprise a chord length which is defined as a length from the trailing edge to the leading edge of the blade. The inventive rotor blade element may prolong the chord length of the rotor blade by connecting an inventive rotor blade element to the trailing edge of the blade.
[0013] Furthermore, the inventive rotor blade element improves the efficiency of the rotor blade and reduces aerodynamic noise generated by a trailing edge of the rotor blade. Moreover, the inventive rotor blade element can be retro-fit to existing rotor blades. As the blade element may be made of a light weight material and/or may be limited in size, a high level of safety can be ensured if, for example, a blade element comes off from a height or falls down from a rotor blade.
[0014] Preferably, the inventive rotor blade element may comprise a trailing edge flange which is adapted for attaching the rotor blade element to the trailing edge of a wind turbine rotor blade. Preferably, the trailing edge flange is located between the contact surface and the suction side surface portion of the inventive rotor blade element. For example, the trailing edge flange may have the shape of an edge.
[0015] The trailing edge flange has the advantage that the suction side surface portion of the rotor blade element may flush with the suction side of the wind turbine rotor blade which is equipped with the inventive rotor blade element. Due to the trailing edge flange the suction side surface portion of the rotor blade element may form an even suction side surface with the suction side of the wind turbine rotor blade.
[0016] The first surface may comprise a curvature, preferably a concave curvature. The curvature can be adapted for prolonging the pressure side of a wind turbine rotor blade. The suction side surface portion of the inventive rotor blade element may also comprise a curvature, preferably a convex curvature. The curvature of the suction side surface portion may correspond to the curvature of the suction side of the wind turbine rotor blade. The curvature can be adapted for prolonging the suction side surface of the rotor blade. Furthermore, the contact surface of the inventive rotor blade element may comprise a curvature, preferably, a convex curvature. The curvature of the contact surface may correspond to the curvature of the pressure side of the blade. Advantageously, the contact surface can be adapted for being attached to part of the pressure side of the wind turbine rotor blade.
[0017] Moreover, the rotor blade element may comprise elastic material. For example, the rotor blade element may comprise plastic material and/or thermoplastic material and/or a composite structure, for example comprising glass fibre. Preferably, the inventive rotor blade element may be made of plastic material and/or thermoplastic material and/or a composite structure like, for example, glass fibre.
[0018] The inventive rotor blade element may elastically bend or deform along the trailing edge of the blade so as to follow the dynamic curvature of the blade to which it is attached during operation. The blade element may further elastically bend or deform in relation to the aero-dynamical influences, like for example wind speed or wind resistance, during operation of the rotor blade.
[0019] Making the blade element of light weight material and limiting the size of the blade element, a high level of safety is ensured, for example, if a blade element is dropped from a height or falls down from a rotor blade. Generally, the inventive rotor blade element can be produced by injecting moulding.
[0020] Moreover, the rotor blade element may have a length, for instance at its trailing edge, of between 0.4 m and 1.0 m. Generally, the inventive rotor blade element can be one long stripe or can be segmented, for example in approximately 0.4 to 1.0 m long segments when attached to a rotor blade. This makes the blade elements easier to handle. Furthermore, the rotor blade element can be extended along substantially the whole length of the trailing edge of the rotor blade or along only the most distal part such as the most distal 8 m, for instance measured from the tip of the blade.
[0021] The inventive rotor blade element may comprise a double-sided adhesive tape for fixing the rotor blade element to the rotor blade. Advantageously, the double-sided adhesive tape can be located at the contact surface. The inventive rotor blade element can be prepared for, and be mounted on the rotor blade by, for example, double-sided adhesive tape. Alternatively, it can be prepared for and be mounted on the rotor blade by glue or a combination of glue and double-sided adhesive tape. The rotor blade element can be mounted, for example glued or taped, on a rotor blade from factory or can be retro-fit.
[0022] The rotor blade element may have a serrated or straight trailing edge.
[0023] Furthermore for various embodiments of the invention, the blade element may be designed to comprise a winglet which may ensure to reduce the fall-speed through open air for a blade element which is falls down from a height. This in turn increases safety for personnel in the vicinity of a turbine which is equipped with the inventive rotor blade element. Therefore, the inventive rotor blade element may advantageously comprise a winglet.
[0024] The inventive rotor blade comprises at least one rotor blade element as previously described. For example, one rotor blade element can be attached to the trailing edge of the rotor blade. Alternatively, a number of rotor blade elements, for example formed as segments, may be attached to the trailing edge of the rotor blade.
[0025] Furthermore, the rotor blade may comprise a tip. The rotor blade element may extend along the whole length of the trailing edge of the rotor blade. Alternatively, the rotor blade element may extend along the length of the trailing edge of the rotor blade of at least 8 m measured from the tip.
[0026] The rotor blade element can be fixed to the rotor blade by glue and/or by tape, for instance by a double-sided adhesive tape.
[0027] The inventive wind turbine comprises at least one rotor blade, preferably three rotor blades, as previously described. Generally, the inventive rotor blade and the inventive wind turbine have the same advantages as previously mentioned in the context with the inventive rotor blade element.
[0028] The inventive method for improving the efficiency of a wind turbine rotor blade is related to a rotor blade which comprises a trailing edge. At least one inventive rotor blade element as previously described is mounted to the trailing edge of the wind turbine rotor blade. Preferably, the at least one rotor blade element is fixed to the rotor blade by glue and/or by tape, for instance by a double-sided adhesive tape. Furthermore, the at least one rotor blade element may be mounted to the trailing edge of a newly manufactured rotor blade or it may be retro-fitted to the trailing edge of an already used or previously manufactured rotor blade.
[0029] The inventive method has the same advantages as the previously described inventive rotor blade element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Further features, properties and advantages of the present invention will become clear from the following description of an embodiment in conjunction with the accompanying drawings. All mentioned features are advantageous separate or in any combination with each other.
[0031] FIG. 1 schematically shows a wind turbine.
[0032] FIG. 2 schematically shows a rotor blade in a plan view on the plane defined by the blade's span and the blade's chord.
[0033] FIG. 3 schematically shows a chord wise section through the airfoil portion of the blade shown in FIG. 2 .
[0034] FIG. 4 schematically shows a rotor blade which is equipped with a number of inventive rotor blade elements.
[0035] FIG. 5 schematically shows an inventive rotor blade element in a perspective view.
[0036] FIG. 6 schematically shows part of a wind turbine rotor blade with an inventive rotor blade element in a perspective and sectional view.
[0037] FIG. 7 schematically shows a further variant of part of an inventive wind turbine rotor blade element in a perspective view.
[0038] FIG. 8 schematically shows the rotor blade element of FIG. 7 equipped with a double-sided adhesive tape in a perspective view.
[0039] FIG. 9 schematically shows another variant of an inventive rotor blade element with a winglet.
DETAILED DESCRIPTION OF THE INVENTION
[0040] FIG. 1 schematically shows a wind turbine 1 . The wind turbine 1 comprises a tower 2 , a nacelle 3 and a hub 4 . The nacelle 3 is located on top of the tower 2 . The hub 4 comprises a number of wind turbine blades 5 . The hub 4 is mounted to the nacelle 3 . Moreover, the hub 4 is pivot-mounted such that it is able to rotate about a rotation axis 9 . A generator 6 is located inside the nacelle 3 . The wind turbine 1 is a direct drive wind turbine.
[0041] FIG. 2 shows a wind turbine blade 5 as it is usually used in a three-blade rotor. However, the present invention shall not be limited to blades for three-blade rotors. In fact, it may as well be implemented in other rotors, e.g. one-blade rotors or two-blade rotors.
[0042] The rotor blade 5 shown in FIG. 2 comprises a root portion 23 with a cylindrical profile and a tip 22 . The tip 22 forms the outermost part of the blade. The cylindrical profile of the root portion 23 serves to fix the blade to a bearing of a rotor hub 4 . The rotor blade 5 further comprises a so-called shoulder 24 which is defined as the location of its maximum profile depth, i.e. the maximum chord length of the blade. Between the shoulder 24 and the tip 22 an airfoil portion 25 extends which has an aerodynamically shaped profile. Between the shoulder 24 and the cylindrical root portion 23 , a transition portion 27 extends in which a transition takes place from the aerodynamic profile of the airfoil portion 25 to the cylindrical profile of the root portion 23 . The span of the blade 5 is designated by reference numeral 28 .
[0043] A chord-wise cross section through the rotor blade's airfoil section 25 is shown in FIG. 3 . The aerodynamic profile shown in FIG. 3 comprises a convex suction side 33 and a less convex pressure side 35 . The dash-dotted line extending from the blade's leading edge 29 to its trailing edge 21 shows the chord 38 of the profile. Although the pressure side 35 comprises a convex section 37 and a concave section 39 in FIG. 3 , it may also be implemented without a concave section at all as long as the suction side 33 is more convex than the pressure side 35 .
[0044] The suction side 33 and the pressure side 35 in the airfoil portion 25 will also be referred to as the suction side and the pressure side of the rotor blade 5 , respectively, although, strictly spoken, the cylindrical portion 23 of the blade 5 does not show a pressure or a suction side.
[0045] FIG. 4 schematically shows a wind turbine rotor blade 5 . A number of inventive rotor blade elements 40 are attached and fixed to the trailing edge 21 of the turbine blade 5 . The rotor blade elements 40 are connected to the trailing edge 21 close to the tip 22 . Preferably, the inventive rotor blade elements 40 cover or extend along at least 8 m of the trailing edge 21 measured from the tip 22 .
[0046] FIG. 5 schematically shows an inventive rotor blade element 40 in a perspective view. The rotor blade element 40 comprises a trailing edge 46 , a first surface 41 and a second surface 42 . The first surface 41 forms a pressure side surface portion, which can be adapted to flush with the pressure side 35 of the rotor blade 5 . The second surface 42 comprises a suction side surface portion 43 , which can be adapted to flush with the suction side 33 of the rotor blade 5 , and a contact surface 44 for connecting the rotor blade element 40 to the pressure side 35 of the rotor blade 5 .
[0047] The inventive rotor blade element 40 further comprises a trailing edge flange 45 , which preferably has the shape of an edge which fits to the trailing edge 21 of the rotor blade 5 .
[0048] The first surface 41 has a concave curvature corresponding to the curvature of part of the pressure side 35 of the rotor blade 5 to prolong the rotor blade 5 in its chord length 38 . The suction side surface portion 43 has a convex curvature corresponding to the convex curvature of the suction side 33 of the rotor blade 5 to flush with the suction side 33 and to prolong the suction side 33 in chord direction 38 . The contact surface 44 has a convex curvature corresponding to the curvature of the concave section 39 of the pressure side 35 to which the contact surface 44 is adapted to be attached to.
[0049] FIG. 6 shows part of an inventive rotor blade 5 to which an inventive rotor blade element 40 is mounted. The inventive rotor blade element 40 is glued or taped with its contact surface 44 to the concave portion 39 of the pressure side 35 of the rotor blade 5 at the trailing edge 21 . The trailing edge 21 is attached to the trailing edge flange 45 .
[0050] The suction side 33 and the suction side portion 42 of the rotor blade element 40 form an even surface, especially with the same convex curvature. Ideally, there is a smooth change from the suction side 33 of the rotor blade 5 to the suction side portion 42 of the rotor blade element 40 . The first surface 41 provides a smooth change to the pressure side 35 of the rotor blade 5 and prolongs the pressure side 45 at the trailing edge 21 of the rotor blade 5 .
[0051] FIGS. 7 and 8 show a further variant of an inventive rotor blade element 50 with a serrated trailing edge 56 . In FIG. 7 part of the rotor blade element 50 is shown in a sectional and perspective view. In FIG. 8 the rotor blade element 50 is shown in a perspective view onto its second surface 42 . In the FIGS. 7 and 8 the trailing edge 56 of the rotor blade element 50 has a serrated shape. Furthermore, in FIG. 8 the contact surface 44 comprise a double-sided adhesive tape 57 , for example, for connecting the rotor blade element 50 to the pressure side 35 of the rotor blade 5 , as shown in FIG. 6 .
[0052] FIG. 9 , schematically shows another variant of an inventive rotor blade element 60 . The blade element 60 comprises a winglet 49 which will ensure to reduce the fall-speed through open air for the blade element 60 in case that it falls down from a height, for example. This increases the safety for personnel in the vicinity of the turbine. | A rotor blade element and a method for improving the efficiency of a wind turbine rotor blade are provided. The wind turbine rotor blade element is adapted for mounting on the wind turbine rotor blade. The wind turbine rotor blade has a trailing edge, a suction side and a pressure side. The blade element has a trailing edge, a first surface and a second surface. The first surface forms a pressure side surface portion. The second surface has a suction side surface portion and a contact surface. | 5 |
FIELD OF THE INVENTION
The present application relates generally to payment systems, cards and methods. More particularly, the present application relates to payment systems that use reward accounts, payment methods that use reward accounts and/or payment cards that use reward accounts.
BACKGROUND OF THE INVENTION
Payment systems typically utilize a payment card (e.g., a conventional credit and debit card). A payment card is generally a piece of plastic material bearing financial information (e.g., credit and debit card numbers) that can be processed to pay for goods or services. Types of payment cards include a credit or debit card, such as those utilizing Visa®, Mastercard®, and American Express® networks. The payment card is issued by a card issuer (e.g., a bank) to a cardholder (e.g., a customer) who uses the card to purchase goods and services.
According to U.S. Patent Application Publication No. 2005/0077350, combination credit/debit cards were developed in the 1990s. To purchase goods or services, a cardholder clerk swipes or otherwise processes the credit/debit card through a point of sale (POS) device (e.g., card reader). The POS device communicates with an open network such as a VISA network.
Financial information obtained from the process is transmitted through the open network and causes a charge to appear either on a credit account or a bank account to pay for the purchased product. Given the pervasiveness of charge cards, credit cards, debit cards, credit/debit cards, and other payment cards, the financial transaction interchange to which charge cards, credit cards, debit cards and credit/debit cards belong can be considered an open network.
U.S. Patent Application Publication No. 2004/0238622 describes that the payment card issuer prefers that the cardholders predominantly use the issuer's payment card (e.g., a credit card) in order to generate the largest amount of fees and revenue. Therefore, the credit card issuer often offers incentives to cardholders who use the issuer's card. The incentives or rewards are accumulated in an account when the cardholder uses the card. The use of incentives benefits the card issuer because the opportunity for the credit card issuer to generate fees and revenue comes with credit card usage. For example, the incentive may be a certain amount of frequent flyer miles, cash, credit towards purchases, points, gifts, etc. These incentives are vigorously promoted by banks and/or card issuing organizations.
Credit and debit cards are being issued by banks and financial institutions in association with other commercial companies or businesses which themselves offer goods and/or services. This phenomena, known as co-branding, provides a credit and/or debit card that often carries a name of the commercial company along with the issuer's name. The commercial company often provides the credit or debit card holder certain benefits which are typically related to the goods or services provided by that commercial company. An example of a co-branded payment card is the General Motors® credit card (Mastercard or Visa) which offers credit card holders 5% of earnings on card purchases toward the purchase or lease of a new General Motors vehicle. The 5% of earnings are accumulated in a rewards account.
Heretofore, payment card rewards have required that the cardholder obtain a payment coupon or certificate once a particular number of reward points were accumulated. Alternatively, other reward programs have required that cardholder call, write and/or otherwise request a certificate or coupon for purchasing a particular product. For example, frequent flyer award programs associated with the credit cards require the cardholder to call the airline and provide a frequent flier number to obtain a ticket based upon frequent flier miles. Other payment card reward systems require that the card holder provides card number information to a web-based redemption site for goods and services in exchange for reward points.
Using coupons, vouchers, gift cards and the like are inconvenient because they require that the customer carry yet another card or papers. Additionally, gift cards, vouchers and coupons require that new codes and account numbers be generated for the transaction. Further, the redeeming store or dealer is inconvenienced by the use of coupons, vouchers, and gift cards because a separate redemption process (separate from the credit card process) is required to authorize the transaction. The separate process requires additional in-store training and separate reimbursement procedures.
U.S. Patent Application Publication No. 2005/0077350 provides a system in which rewards or award points can be redeemed using an automated system. U.S. Publication No. 20051/0077350 discloses a closed network for redeeming award points. However, a closed network requires an additional cost and training for providers of the services.
Thus, there is a need for a payment card system that facilitates easy access to redeeming rewards at participating stores, dealers, outlets or service providers. Further, there is a need for a credit card or debit card system that includes a debit card number (or an additional debit card number) that is operable on existing networks for redeeming reward balances. Yet further, there is a need for an open network for redeeming reward balances. Yet further still, there is a need for a payment card optimized for easy redemption of rewards from the merchant's, card issuer's and/or card user's perspective.
SUMMARY OF THE INVENTION
An exemplary embodiment relates to a financial system including an integrated credit/debit reward card including a payment card number associated with a payment account and a debit card number. The debit card number is different than the payment card number and is associated with a debit account. Purchases using the payment card increase the debit account based upon a reward scheme. The financial system also includes point of sale equipment for processing the payment card number and the debit card number. The payment card number and the debit card number are processed utilizing the same network.
Another embodiment relates to a method of procurement using a payment card. The payment card has a debit card number associated with a first account. The payment card also includes a second number associated with a second account. Use of the second number to purchase goods or services may result in an accumulation in the first account. The method includes providing the payment card to a merchant, determining whether to use the first number or the second number to at least partially purchase a good or a service, and using a point of sale device to process the debit card number. The point of sale device is capable of processing the second number for purchases of goods or services. The method also includes consummating a transaction upon receiving verification.
Still another exemplary embodiment relates to an integrated rewards card. The integrated rewards card includes a payment card number associated with a payment account of a person, persons, an entity or a business. The integrated rewards card also includes a debit card number. The debit card number is different than the payment card number. Purchases using the payment card number cause a reward balance on a reward account associated with a debit card number to be increased. Products or services can be purchased with the reward account using a POS device for the payment card number.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the present invention are described below with reference to the accompanying drawings, where in like numbers denote like elements and:
FIG. 1 is a general block diagram depicting a financial system in accordance with an exemplary embodiment.
FIG. 2 is a top view drawing of a payment card for use in the financial system illustrated in FIG. 1 .
FIG. 3 is a bottom view drawing of the payment card illustrated in FIG. 2 .
FIG. 4 is a flow diagram depicting an exemplary operation for record redemption in the financial system of FIG. 1 .
FIG. 5 is a flow diagram depicting an exemplary operation for a customer applying for and being issued an Integrated Reward Card to be processed in the financial system of FIG. 1 .
FIG. 6 is a flow diagram depicting an exemplary operation a customer using an Integrated Reward Card in the financial system of FIG. 1 .
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
FIG. 1 illustrates a financial information system 10 which is configured for procuring goods and services using a reward-type payment card infrastructure. Financial system 10 generally includes an integrated payment card 15 , a point of sale device 25 , a network 55 , a debit account 35 and a payment account 45 . Device 25 is preferably coupled to debit account 35 and payment account 45 through network 55 . Although shown with two communication lines in FIG. 1 , system 10 can utilize any communication system for accessing account 35 and 45 .
Network 55 is preferably an open network for processing payment card transactions, such as credit and debit card transactions. Network 55 can involve a number of wide area networks (WANs), local area networks (LANs), servers, routers and other communication and computing components. Network 55 provides the infrastructure necessary for communication between device 25 and accounts 35 and 45 .
Point of sale device 25 can be any type of device for processing payment card transactions (e.g., credit card and/or of debit card transactions). In one embodiment, point of sale device 25 can be a card reader device. Device 25 can include a key pad for entering information (e.g., numbers) on card 15 . An exemplary device 25 is a T7P type POS device manufactured by Hypercom.
An exemplary payment card 15 is described with respect to FIGS. 2-3 . Financial operations associated with such a card are described below with reference to FIGS. 4-6 . The term payment card as used below refers to a card used for making purchases (e.g., a credit or debit card). Payment Card 15 can have any shape or size depending on design criteria and can be fabricated from any material without departing from the scope of the invention.
Financial system 10 can be implemented as a software application written in any language or technology (e.g., Cobol, JAVA, J2EE, or .Net) and supported on secured servers or other hardware. Network 55 can include a myriad of financial processing tools including security software, communication software, etc. Accounts 35 and 45 are preferably located in computing equipment (e.g., servers, networks, mainframes, etc.) operated or controlled by the card issuer. The card issuer's computing equipment communicates with the vendor and/or device 25 through network 55 .
System 10 advantageously utilizes integrated payment and reward cards 15 . Preferably, card 15 is embodied as a Visa or Mastercard credit card or debit card including novel debit card functionality against a reward balance. Card 15 is preferably configured to nearly seamlessly allow transactions based upon either of accounts 35 and 45 .
Card 15 preferably includes indicia of the credit card number (for account 45 ) as well as at least partial indicia of the debit card number (for account 35 ). In one embodiment, card 15 includes a credit card number embossed on the front of card 15 and a debit card number printed on the back of card 15 in a non-embossed fashion, such as by spray printing. Preferably, the debit card number printed on the back of card 15 does not include the first four digits of the debit card number for security purposes. The first four digits can be the bank identification number (BIN) or a portion thereof.
The credit card number corresponds to the payment account 45 and the debit card number corresponds to the debit account 35 . Use of the payment account 45 for purchasing goods or services results in accumulation in debit account 35 (e.g., a reward account, award account, etc.). According to a rewards scheme, additional points can be rewarded upon other bases, such as purchases from particular merchants. Debit account 35 can hold points, monetary value, or other indicia of rewards. In addition, cash, certificates or other financial instruments can be placed and accounted in debit account 35 .
Debit account 35 preferably has a 16-digit debit account number. The debit account number can have a conventional VISA or Mastercard format. Similarly, payment account 45 has a 16-digit payment account number. The payment account number also can have a conventional VISA or Mastercard format. Preferably, at least the first four digits of the credit and debit account number refer to a bank identification number (BIN).
As discussed above, the bank identification number for debit account 35 is preferably not printed on payment card 15 . However, the first four digits of debit account 35 and payment account 45 are the same. A merchant or store handling a redemption from debit account 35 can utilize the first four digits from the credit card number with the remaining numbers printed on the back of card 15 to complete the number for debit account 35 . Preferably, card 15 has the same expiration date for debit account 35 and payment account 45 .
By printing the debit account number for debit account 35 on the back of card 15 , the bank is able to obscure the fact that payment card 15 includes an active debit card number. Card 15 can also include payment account number for account 45 and the debit account number for debit account 35 encoded on a single magnetic strip or on separate magnetic strips.
In addition, other account numbers can be added to card 15 . According to an alternative embodiment, card 15 can have the entire debit card account number for account 35 printed or embossed on card 15 .
In operation, system 10 advantageously eases redemption from debit account 35 for both a dealer and customer. Payment card 15 allows the customer to carry a single card for both accounts 35 and 45 and allows the dealer to process the account through the same network 55 and point of sale device 25 to reach either debit account 35 or payment account 45 .
The dealer advantageously can be reimbursed via the same settlement processes utilized for a conventional credit card account, according to one embodiment. According to another embodiment, store personnel can advantageously utilize the same type of point of sale device 25 as it would for an ordinary credit card. In addition, separate settlement procedures are not required for the dealer as settlement can be advantageously combined with other card activity.
Financial system 10 also provides significant advantages with respect to security by allowing authorization restrictions on debit account 35 . For example, debit account 35 can have authorization restrictions so that purchases from only specifically identified dealers or groups of dealers are allowed. All other transactions can be declined through network 55 and/or the bank. In one embodiment, card 15 is configured so that no authorization stand-in approvals is allowed.
Financial system 10 leverages already existing infrastructure through network 55 and private label functionality so that no new networks or connections are required at participating redemption dealers. System 10 can also be configured to include additional accounts provided on same integrated rewards card 15 . In a preferred embodiment, system 10 is utilized in a co-branding fashion in which debit account 35 is meant to be redeemed at particular stores or with a particular product line.
With reference to FIGS. 2 and 3 , a front side 28 of card 15 includes a payment card number (e.g., credit card number) 100 . As shown in FIG. 2 , number 100 is preferably a 16-digit number with at least the first four digits being the bank identification number. Preferably, number 100 is embossed on the front of the card and the first four digits are also printed on the front of the card at a location 102 . Face 28 can also include various indicia of co-branding, such as a dealer's trademark or other indication of the link to a particular type of reward account.
In FIG. 3 , a back 200 of card 15 includes a debit card number 205 corresponding to account 35 . Debit account number 205 preferably includes only 12 digits. Number 205 preferably does not include a bank identification number. The bank identification number as printed in number 100 or at place 102 . The bank identification number can be utilized to complete the debit card number.
The placement of numbers 100 , 205 and other indicia is not shown in a limiting fashion. Further, the various other indicia shown in FIGS. 2 and 3 is exemplary only and not shown in a limiting fashion.
Back 200 can include a magnetic strip 208 for including one or both of numbers 100 and 205 . In operation, a customer redeems a reward balance from debit account 35 by presenting card 15 to a clerk or merchant and indicating that the customer wants to pay for goods or services with their reward points. The clerk can key enter number 205 into point of sale device 25 or utilize a card swiping process. Alternatively, chip technology in place of magnetic strip technology can be utilized.
After the clerk key enters the debit card number 205 and the transaction amount into point of sale device 25 , network 55 is utilized to route the authorization to the issuer of integrated payment and rewards card 15 . Preferably, network 55 is the same network used to route authorization for the user of payment account 45 . In a preferred embodiment, network 55 is a Visa or Mastercard network that routes authorization to the issuer such as a bank or a partner of a bank, or other institution. Authorization is preferably performed in the same fashion as other credit and debit card authorizations.
When the authorization request is received by the issuer, special authorization rules are preferably implemented in software. The software recognizes that the request is using account number 205 as a special reward redemption authorization. The software confirms that the transaction is occurring at the appropriate merchant via merchant category code (MCC), merchant name, specific terminal, or other ID field information. The transaction amount is compared to the available reward balance in debit account 35 and approve/decline decision is returned to the clerk.
Settlement for the merchant occurs with all other debit or credit card transactions that participating merchant store has done during the day. As point of sale device 25 is settled and closed, the reward transaction is included. Settlement occurs as part of the acquiring functionality and settlement with the cardholder occurs as the transaction posts.
With reference to FIG. 4 , flow diagram 500 provides an automated rewards redemption for a dealer co-sponsored credit or debit card. However, flow diagram 500 and system 10 can be utilized in a non co-branding situation. In diagram 500 , a customer or cardholder 502 enters a dealer 504 and requests a redemption from debit account 35 .
A clerk at dealer 504 either through voice authorization on telephone 37 or point of sale device 25 enters number 205 from card 15 . The clerk includes the missing four digits for a complete account number for debit account 35 which is received at merchant processor 506 . The request includes the transaction amount and can also identify the goods or services being purchased.
Merchant processor 506 provides the request through Visa network 508 to a mainframe 510 . Mainframe 510 is preferably controlled by the card issuer. Mainframe 510 recognizes number 205 as a special number associated with debit account 35 and authorizes the transaction based upon reward points as opposed to credit lines or other balances cardholder has at the institution associated with a computing platform C (e.g., mainframe 510 ).
In addition, mainframe 510 can check the expiration date of card 15 . Mainframe 510 also tracks the transaction amount. Mainframe 510 can further verify the merchant code, the merchant and the product type to ensure that these factors meet the redemption rules for account 35 .
Once the transaction is authorized, award points from debit account 35 are decremented by mainframe 510 . Mainframe 510 can be coupled to a mainframe 520 associated with dealer 504 . Mainframe 510 can provide reports to mainframe 520 . Mainframe 510 can transact with other financial institutions associated with dealer 504 .
The customer can also choose to utilize its ordinary credit card number 100 for the transaction. For such a transaction, the clerk runs the process through network 508 to mainframe 510 . Mainframe 510 recognizes number 100 as an ordinary credit card transaction or debit card transaction and process the transaction accordingly. Reward points are accumulated in account 35 for purchases made through account 45 .
With reference to FIG. 5 , a flow diagram 700 shows a process for providing a payment card 15 to a customer 701 . At a step 702 , underwriting begins. Step 702 can begin in response to an application by customer 701 , a web request, phone request, etc. At step 704 , an interface with posting process 706 is made. The posting process enables payment card 15 to be utilized according to flow diagram 500 .
At a step 708 , account 45 is tied to a particular credit/debit card number for account 45 and a debit account number for account 35 . The relationship between account 35 and 45 and rewards scheme is also recorded.
At a step 710 , the credit card is booked to a master file of credit cards for the credit card issuer (e.g., bank). At a step 712 , account 35 is booked in a master file of debit cards for the card issuer (e.g., bank). At a step 714 , the plastic credit card is produced as payment card 15 .
At a step 716 , maintenance associated with account 35 and 45 is performed (e.g., lost and stolen credit cards). Maintenance also includes maintaining accounts 35 and 45 in response to transactions and audit logs.
In FIG. 6 , a flow diagram 800 generically shows the use of payment card 15 . A request comes from Visa, MasterCard, Discover or any credit card institution 802 to the credit card issuer's authorization system 804 . System 804 obtains a file 816 associated with payment card 15 and accounts 35 and 45 . File 816 contains information about account 45 and 35 and payment card 15 . Preferably communication between a credit card institution 802 and system 804 is a real time or near real time transaction.
System 804 communicates with a posting process system 806 . Posting process system 806 also receives daily settlement information from credit card institution 802 . System 806 communicates with a redemption system 808 which calculates reward balances are stored in file 818 . Authorization system 804 utilizes file 818 to determine if account 35 has enough points or other rewards for a purchase using account 35 . Daily settlement information is communicated between institution 802 and system 806 .
While several embodiments of the invention have been described, it is to be understood that modifications and changes will occur to those skilled in the art to which the invention pertains. For example, although the term “banking” is used to desire the financial system 10 , the system is not limited to operation by a bank or credit union. Any entity could provide the financial system 10 . System 10 can utilize co-branding in any field including but not limited to automobile manufacturers, airlines, clothing stores, restaurants, electronic stores, grocery stores, etc. Accordingly, the claims appended to this specification are intended to define the invention precisely. | An integrated rewards card includes a credit card number associated with a credit account of a person, persons, entity or a business. The integrated rewards card also includes a debit card number. The debit card number is different then the credit card number. Purchases using the credit card number cause a reward balance on a reward account associated with the debit card number to be increased. Products or services can be purchased with the reward account using a point of sale device for the credit card number. | 6 |
RELATED APPLICATIONS
This application claims the benefit of, and priority to, both of the following two commonly-invented U.S. Provisional applications: (1) Ser. No. 61/735,819, filed Dec. 11, 2012; and (2) Ser. No. 61/811,760, filed Apr. 14, 2013.
GOVERNMENT LICENSE RIGHTS
This invention was made with Government support under Contract No. R12PX80431 awarded by the United States Bureau of Reclamation. The U.S. Government has certain rights in the invention.
FIELD OF THE INVENTION
The disclosure of this application is related generally to RFID antennal systems, and more specifically to submersible applications of such systems (such as in flowing streams or rivers) that are useful to monitor, for example, the migration and biometrics of underwater species.
BACKGROUND
The use of Radio Frequency Identification (“RFID”) tags to monitor migration or biometrics of species is well known in the art. It is also well known to implant such RFID tags subcutaneously, within the musculature or within the body cavity of fish and other underwater species. Transponders suitable for implantation in fish and other underwater species necessarily have to be small, and are typically glass-encapsulated in order to be biologically inert.
Numerous types and styles of air or ferrite core antennas have been developed and used for underwater interrogation of RFID tags on fish and other underwater species. Typically such antennas include an air core antenna that is positioned flat on a substrate and deployed in a housing. The housing may be plastic pipe, or welded sheets of plastic, or similar materials and construction. Multiple wire coils may also be deployed within such a housing, typically held in position relative to each other, and as a unit, within a gallery or similar structure.
The charging and reading zone for small glass-encapsulated transponders is typically limited to distances less than 2.5 feet in the zone immediately above the antenna. Precise performance depends on factors such as the type and quality of the transceiver and antenna system, the level of ambient electromagnetic interference and the operable quality of the RFID tag itself. Some conventional air coil antennas are known to be mounted upright within the water column, perpendicular to the flow of water. Such placement has shown a tendency to increase the charging zone or read zone of transponders. Properly configured and deployed at appropriate settings, the charging zone and read zone of such antenna systems can extend to the entire water column. However, the placement of such antennas, coupled with their vertical orientation, makes these more likely to be damaged by floating debris and high water velocities in streams and rivers, especially during seasonal high water events.
Therefore, there exists a need for an improved antenna system that can read RFID tags throughout the entire water column, and yet withstand the potential physical abuse in stream or river deployments caused by high water velocity or turbulence, or by impact with moving debris or ice.
SUMMARY AND TECHNICAL ADVANTAGES
The inventive disclosure of this application addresses one or more of the above-described drawbacks of the prior art. Such inventive disclosure includes an array of RFID antennas configured, at a rest position, in a substantially vertical or angled (parallel to flow, deflecting downstream) underwater orientation. For moving water deployments (such as rivers or streams), the antennas provide a hydrodynamic teardrop-shaped profile in cross-section, in which the teardrop shape has an elongated tail. The antennas are oriented such that the tail is deployed on the downstream side of the flow of water past the array. The symmetric nature of the hydrodynamic teardrop shape keeps lateral hydrodynamic/hydraulic forces on the antenna neutral, while also minimizing the effects of hydrodynamic drag and flow-induced vibration exerted on the antennas by the flow of water past the antennas in the array.
Each antenna in the array is further held in place via a pivoting structure that acts like a hinge at one of either ends. The pivots are oriented generally so that, in moving water deployments, individual antennas may pivot independently downstream responsive to temporary (or even momentary) bursts of additional force caused by, for example, seasonal high water flow, turbulence or passing or accumulating debris.
As noted, an array of antennas may deploy its antenna pivoting structure at either end of the antennas. That is, top-end pivoting embodiments of antenna arrays may provide the pivoting structure at the water surface end of each of the vertically-disposed antennas, while basal-pivoting embodiments of arrays may provide the pivoting structure at the riverbed (or other ground bottom) end. Top-end pivoting embodiments, in which each antenna pivots independently from a hinged connection at the water surface end, provide pivoting and suspension of the antennas via a cable or solid member strung above the antennas and transverse to the direction of water flow. Basal-end pivoting embodiments, in which each antenna pivots independently from a hinged connection at the river bed end, provide a pivot assembly connected to the basal end of each antenna via in currently preferred embodiments, a substantially horizontally-disposed pin or axle. The pin on each pivot assembly is oriented transverse to the direction of water flow so as to allow antennas to rotate in a substantially vertical plane of water flow about the pin. Each pivot assembly is in turn anchored to the river bed (or other user-selected plane of anchoring). Future embodiments of the pivot assembly may include inventive technology in which the pivot assembly is either partially or fully articulated, so that antennas may also deflect laterally, in planes other than the vertical plane of water flow.
In top-end pivoting arrays of antennas, counterweighting deployed at or near the other (basal) ends of each antenna cause the antennas to tend to return to a substantially vertical or angled (parallel to flow, deflected downstream) rest position in the water column. Conversely, basal-end pivoting arrays of antennas rely on the natural buoyancy of each antenna to cause the antenna to tend to return to a substantially vertical or angled (parallel to flow, deflected downstream) rest position in the water column. The air core antenna housing naturally creates this buoyancy and additional assistance to return to the rest position may be provided by torsion springs built into the pivot assembly, as further described below.
Antennas in each array are multiplexed or synchronized electronically to transceivers that may be mounted in any suitable location, such as within the antenna housing, the housing cap, the antenna base, on shore, or nearby underwater. Each antenna may be driven by a single transceiver, or alternatively multiple antennas may be powered by a single transceiver or a single channel on a multi-channel transceiver.
It is therefore a technical advantage of the vertically-oriented antenna arrays disclosed herein to be less susceptible, in moving water deployments, to damage from high velocity or high turbulence water flows, or from passing or accumulating debris. According to the disclosure herein, antennas may deflect and thus shed debris rather than receiving the full impact of passing debris, or providing a point for accumulation of debris.
A further technical advantage of the vertically-oriented antenna arrays disclosed herein is that by tending to return to a vertical or angled (parallel to flow) rest position, they are able to detect and interrogate passing RFID tags (attached to underwater species) more consistently over the entire water column.
A further technical advantage of the vertically-oriented antenna arrays disclosed herein is that they can be used to set up variable sampling schemes to collect data for more precise statistical analysis. Multiplexing and/or synchronization of the individual antennas enable such sampling schemes, in that the antenna array divides the water course cross-section into discrete vertical read zones within which all tagged species have a high likelihood of being detected. The electronic controller may then be used to differentially focus the sampling effort on vertical read zones in which tagged species are more likely to travel, thus enhancing the quality and amount of data collected. Subsequent statistical analysis may then include analysis of RFID tag detection rates and hence estimates of the numbers of fish, for example, passing the site.
The foregoing has outlined rather broadly the features and technical advantages of the inventive disclosure of this application, in order that the detailed description of the embodiments that follows may be better understood. It will be appreciated by those skilled in the art that the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same general purposes of the inventive material set forth in this disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of embodiments described in detail below, and the advantages thereof, reference is now made to the following drawings, in which:
FIG. 1 illustrates one top-end pivoting embodiment of the inventive antenna arrays disclosed in this application;
FIG. 2 illustrates a basal-end pivoting embodiment of the inventive antenna arrays disclosed in this application;
FIG. 3 illustrates an antenna assembly from FIG. 2 in isolation, comprising an antenna housing, a housing cap and an antenna base; and
FIG. 4 is a section of FIG. 3 's antenna housing, as further shown on FIG. 3 .
DETAILED DESCRIPTION
FIG. 1 illustrates one example of a top-end pivoting embodiment of the vertically-oriented antenna arrays disclosed herein. It will be seen on FIG. 1 that the array 100 is deployed in moving water (such as a stream or river) with a nominal direction of water flow as indicated by arrow WF. Each antenna comprises an elongate antenna housing 101 having a hydrodynamic teardrop shape in cross-section. The advantageous hydrodynamics of the hydrodynamic teardrop shape are discussed above in the first paragraph of the “Summary” section of this disclosure. This inventive disclosure is not limited, however, to antenna housings with a teardrop shape in cross-section. In other embodiments (not illustrated), the antenna housing's cross-sectional shape may also be round, ovate, oblong, square or another shape befitting the installation conditions and antenna windings.
The external shell of antenna housing 101 is made of non-ferrous materials such as, without limitation, non-ferrous metals or alloys, wood, plastics, rubber, fiberglass, carbon fiber or resins. Antenna housing 101 may also be coated on the outside with materials or resins selected to increase durability or protect against abrasion. For wood shells, waterproofing is advantageous using resins or the like.
Each antenna on FIG. 1 provides first end 108 and second end 109 , and is suspended from a support cable 102 at first end 108 . The support cable 102 may be suspended from any suitable anchoring points, such as, for example, anchors on the shore or on banks of a river, or permanent concrete structures in the water itself. In preferred embodiments, the support cable 102 on FIG. 1 will be understood to be disposed substantially perpendicular to the direction of water flow WF, so that each antenna remains substantially in the vertical plane of water flow WF, although the inventive material disclosed herein is not limited in this regard. The support cable 102 may be deployed at other angles with respect to the direction of water flow WF, per user selection, and a swivel mechanism in the pivot assemblies 103 (as described further below) enables each antenna nonetheless to remain substantially in the vertical plane of water flow WF. The support cable 102 may be made from any conventional metallic or non-metallic construction.
In FIG. 1 , the support cable 102 is illustrated as located above the water surface WS. However, the inventive material disclosed herein is not limited in this regard. Other embodiments (not illustrated) may deploy the support cable 102 below the surface of the water at user-selected depths. Such other embodiments (not illustrated) may also set the support cable 102 at other user-selected orientations and anchor points.
FIG. 1 also illustrates the support cable 102 being available to support one or more power and/or communications cables 105 addressing each of the antennas. Such power or communications cables 105 connect the antennas to a power supply, a transceiver and other hardware that may be located elsewhere, such as on the shore, within the antenna housing 101 , or nearby underwater. Each antenna may receive a separate power and/or communications cable 105 , or alternatively a single power and/or communications cable 105 may be attached to one end of the array 100 and pass through to neighboring antennas.
FIG. 1 further illustrates each antenna suspended from the support cable 102 by its own pivot and swivel assembly 103 . In current embodiments, the design and construction of the pivot and swivel assemblies 103 is conventional, although in future embodiments it may be inventive. As noted above, the swivel structure in the pivot and swivel assemblies 103 allows each antenna to remain oriented substantially in the vertical plane of water flow WF. The pivot structure in the pivot and swivel assemblies 103 leaves the antenna free to rotate about the support cable 102 . Each hanging antenna may thus deflect responsive to temporary (or momentary) bursts of force or impact placed upon it by events such as seasonally high water flows, turbulence, or passing or accumulating debris. Such deflection will be understood to be primarily by rotating about the support cable 102 in the vertical plane of water flow WF. However, in preferred embodiments, each pivot and swivel assembly 103 is also sufficiently articulated to permit its corresponding antenna to deflect in other planes as well.
Counterweights 107 are also illustrated on FIG. 1 at the basal (riverbed S) end of each antenna. These counterweights 107 operate to cause the antennas to tend to return to a vertical or angled (parallel to flow, deflected downstream) rest position after momentary deflection by, for instance, passing or accumulating debris. Alternatively a portion of the antenna housing 101 may be flooded with water to create a neutrally buoyant antenna, requiring little (if any) further counterweighting.
It will be appreciated from FIG. 1 that an array of antennas may be dimensionally configured by user selection of the lengths of the antennas and the spacing along the support cable at which each one is fixed. RFID charge and read zones CRZ are thus created between the antennas that extend nominally the entire length of antennas (as shown on FIG. 1 ). When the length of antennas is selected to be long enough, the entire depth of the water column potentially becomes available for RFID tag detection and interrogation. RFID charge and read zones CRZ will be only temporarily compromised while antennas deflect, and will be restored when the antennas return to their substantially vertical or angled (parallel to flow, deflected downstream) rest position.
Top-end pivoting antenna embodiments, such as illustrated on FIG. 1 , are useful where basal-end pivoting embodiments, such as illustrated on FIGS. 2 through 4 , are not possible or desirable. For example, basal-end pivoting embodiments may not be suitable at or near engineered water project infrastructure such as concrete fishways, dam spillways, penstock or other turbine entryways, sluice gates, or canals. Such environments tend to operate in higher water velocities, and may further present logistical challenges in physically accessing the riverbed or bottom in order to anchor and service a basal-end pivoting embodiment.
FIGS. 2 through 4 illustrate one example of a basal-end pivoting embodiment of the vertically-oriented antenna arrays disclosed herein. It will be understood on FIG. 2 , that the array 200 is deployed in moving water (such as a stream or river) with a nominal direction of water flow WF. As on FIG. 1 , each antenna on FIG. 2 also comprises an elongate antenna housing 201 having a hydrodynamic teardrop shape in cross-section, with first end 208 and second end 209 . The advantageous hydrodynamics of the hydrodynamic teardrop shape are discussed above in the first paragraph of the “Summary” section of this disclosure. This inventive disclosure is not limited, however, to antenna housings with a teardrop shape in cross-section. In other embodiments (not illustrated), the antenna housing's cross-sectional shape may also be round, ovate, oblong, square or another shape befitting the installation conditions and antenna windings.
The external shell of antenna housing 201 is made of non-ferrous materials such as, without limitation, non-ferrous metals or alloys, wood, plastics, rubber, fiberglass, carbon fiber or resins. Antenna housing 201 may also be coated on the outside with materials or resins selected to increase durability or protect against abrasion. For wood shells, waterproofing is advantageous, using resins or the like.
Turning momentarily to FIGS. 3 and 4 , FIG. 3 illustrates an antenna assembly from FIG. 2 in isolation, comprising an antenna housing 201 , a housing cap 203 and an antenna base 207 . Common features illustrated on FIGS. 2 through 4 share the same reference numeral. FIG. 4 is a cross-section of FIG. 3 as shown on FIG. 3 , and illustrates the hydrodynamic teardrop-shaped profile of the antenna housing 201 as described in the preceding paragraph with reference to FIG. 2 , and earlier in this disclosure in the first paragraph of the “Summary” section. For the avoidance of doubt, the hydrodynamic teardrop-shaped profile illustrated on FIG. 4 is symmetric about a centerline axis H-H as illustrated.
Returning to FIG. 2 , each antenna housing 201 in FIG. 2 is connected to an antenna base 207 . Pivot and swivel mechanisms 205 are in hinged connection with each antenna base 207 . In current embodiments, each pivot and swivel mechanism 205 is anchored to the riverbed or ground bottom S by conventional anchoring technology 202 , although future embodiments may include inventive anchoring technology. In preferred embodiments, each pivot and swivel assembly 205 is anchored to the bottom S in spaced relationship, per user selection, in a line that runs perpendicular to the direction of water flow, so that each antenna may remain substantially in the vertical plane of water flow. The inventive material disclosed herein, however, is not limited in this regard. In other embodiments (not illustrated), pivot and swivel assembly anchoring may be in other angles or shapes with respect to the direction of water flow, per user selection. Swivel structure on the pivot and swivel assembly 205 (as described further below) enables each antenna nonetheless to remain substantially in the vertical plane of water flow.
As discussed elsewhere in this disclosure, the hinged connection between the antenna base 207 and the upper portion of the pivot and swivel assembly 205 may, in some embodiments, be further restrained by torsion springs set to return the antenna to a vertical or angled (parallel to flow) rest position after deflection.
FIG. 2 also illustrates power and communications cables 204 being brought along the river bed or ground bottom S to address and serve each antenna. Connection and anchoring of the power and communication cables 204 may be by any conventional waterproof method so that electrical signals and communications in the cables are not compromised. As on FIG. 1 , the power and communications cables 204 on FIG. 2 connect the antennas to a power supply, a transceiver and other hardware that may be located within the antenna housing 201 , the housing cap 203 , the antenna base 207 or elsewhere, such as on the shore or nearby underwater. Each antenna may receive a separate power and/or communications cable 204 , or alternatively a single power and/or communications cable 204 may be attached to one end of the array 200 and pass through to neighboring antennas.
Current embodiments of the pivot and swivel assemblies 205 illustrated on FIG. 2 are of conventional design and manufacture, although future embodiments may include inventive technology. A lower portion of each pivot and swivel assembly 205 is anchored to the bottom S. The lower portion is in vertical swivel connection with an upper portion, so that when an antenna is attached to the upper portion, the antenna is free to swivel about a vertical axis. The upper portion is further disposed to receive an antenna base 207 via a generally horizontal hinged connection. When an antenna is in hinged connection (via its antenna base) to the upper portion of a corresponding pivot and swivel assembly, the antenna is free to pivot about the hinge 206 , and so essentially becomes free to pivot about the bottom S (or other substantially horizontal plane at which the pivot and swivel assembly 205 may be anchored).
FIG. 3 illustrates the antenna base 207 in isolation, and shows the antenna base's portion of the hinged connection to the upper portion of a corresponding pivot and swivel assembly 205 . FIG. 3 also illustrates the axis of pivot P about which the antenna is free to rotate. It will be understood from viewing FIGS. 2 and 3 together that a conventional pin or axle 206 may be used to form a hinged connection between the antenna base 207 and the upper portion of a corresponding pivot and swivel assembly 205 that permits multi-axial movement.
As noted above, the swivel structure in the pivot and swivel assemblies 205 leaves each antenna free to remain oriented substantially in the vertical plane of water flow. The pivot structure in the pivot and swivel assemblies 205 leaves the antenna free to rotate about the river bed S (or other substantially horizontal plane of anchoring). Each antenna may thus deflect responsive to temporary (or momentary) bursts of force or impact placed upon it by seasonally high water flows, or turbulence, or passing or accumulating debris. Such deflection will be understood to be primarily by rotating about the river bed S (or other substantially horizontal plane of anchoring) in the vertical plane of water flow. However, as illustrated on FIGS. 2 and 3 , each pivot and swivel assembly 205 provides independent pivot structure and swivel structure to permit its corresponding antenna to deflect in multiple planes. It will be appreciated that although current embodiments of pivot and swivel assembly 205 are illustrated on FIGS. 2 and 3 , future embodiments may also provide partial or full articulation at the antenna base 207 connection to the pivot and swivel assembly 205 . Such articulation will enhance the ability of the antenna to deflect in multiple planes.
Housing caps 203 are also illustrated on FIGS. 2 and 3 at the top (water surface WS) end of each antenna. In some embodiments, these caps 203 may physically house each antenna's transceiver, thereby isolating them from electromagnetic interference generated by the antenna coil itself. The caps 203 further provide a construction seal for the top (water surface WS) end of the antenna housing 201 . When sealed by the cap 203 and at the antenna base 207 , the air core antenna assembly (which is buoyant) operates to cause the antenna to tend to return to a vertical or angled (parallel to flow, deflected downstream) rest position after momentary deflection by, for instance, passing or accumulating debris. Plastic and other buoyant materials used in the construction of the antennas, and torsion springs within the basal pivot and swivel mechanisms 205 will also be understood to assist the antennas to tend to return such vertical rest or angled position. A user-selected amount of buoyancy for any embodiment of the vertical antenna system may be controlled by a variety of mechanisms, including flooding portions of each antenna housing 201 with water.
Similar to disclosure above with reference to FIG. 1 , it will be appreciated from FIG. 2 that an array of antennas 200 may be dimensionally configured by user selection of the lengths of the antennas and the spacing along the bottom at which each one is anchored. RFID charge and read zones CRZ are thus created between the antennas that extend nominally the entire length of antennas (as shown on FIG. 2 ). When the length of antennas is selected to be long enough, the entire depth of the water column potentially becomes available for RFID tag detection and interrogation. RFID charge and read zones CRZ will be only temporarily compromised while antennas deflect, and will be restored when the antennas return to their substantially vertical or angled (parallel to flow) rest position.
Although the inventive material in this disclosure has been described in detail along with some of its technical advantages, it will be understood that various changes, substitutions and alternations may be made to the detailed embodiments without departing from the broader spirit and scope of such inventive material as set forth in the following claims. | An underwater basal-pivoting antenna assembly (or array thereof) suitable for subsurface RFID tag interrogation in flowing water such as a river. In preferred embodiments, the antenna interrogates RFID tags implanted in aquatic species. The antenna resides in an elongate antenna housing whose cross-sectional shape is preferably a hydrodynamic teardrop shape. When the assembly is deployed in water with a lower end thereof anchored below an upper end, the lower end of the housing is linked to a pivot/swivel mechanism such that when the pivot/swivel mechanism is held substantially stationary with respect to the water flow, the upper end of the housing is free to rotate generally about the first end, including in a substantially vertical plane parallel to the water flow direction. The length of the antenna housing is advantageously selected to enable the antenna to monitor for signals across substantially the entire water depth. | 0 |
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