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BACKGROUND
1. Technical Field
The present invention relates to a test system for simulating impairments, including losses, errors, noise and jitter, in a network wireless communication signal to enable estimation of the resulting degradation in voice or video quality.
2. Related Art
Operators need to ensure that their systems provide excellent multimedia quality. Every time a new handset is introduced, it should be tested to make sure it produces clear audio and video under ideal and under degraded coverage conditions.
FIG. 1 illustrates the classic test system to measure media quality in a wireless system. Typically the media quality is measured or estimated for voice media or for video media. As shown, the system includes two User Equipment (UE) devices 2 and 4 which enable telephony type voice communications over a wireless link. The devices 2 and 4 can be cellular mobile phones. The UE 2 is used by a speaker to provide a voice reference media 1 that is converted by the UE 2 to a packet data signal and transmitted over a wireless air interface link 6 to a wireless system 8 . The wireless air interface link 6 is part of a first Radio Access Network (RAN) and can carry mobile phone signals such as LTE, UMTS, CDMA or GSM signals. The wireless system 8 can include a base station for mobile phone communications. The wireless system 8 then communicates the packet data signal again through another wireless interface link 10 of a second RAN to another UE 4 . The UE 4 is also the Device Under Test (DUT) as it converts the packet data signal back to an audio signal that is provided through a speaker of the DUT UE 4 for listeners to hear. The audio signal played through the speaker provides a degraded media signal 11 to listeners. The listeners then determine the quality of the degraded media signal.
Voice quality of a connection can be measured and reported in many ways. Historically the preferred method was to let a panel of listeners, as illustrated in FIG. 1 , evaluate the perceived received quality of the audio received from one or more speakers. The resulting scores were averaged and captured as a Mean Opinion Score (MOS). The MOS scale ranges from 1 (bad) to 5 (excellent). The score for a wireless connection depends on the codec, or signal encoding and decoding method that is used. The score also strongly depends on the latency and reliability of the air interfaces 6 and 10 . For instance GSM has a value of 3.5 and AMR-WB has a value of 4.2.
Evaluating a MOS with real listeners is subjective and a large number of listeners must be used. Gathering people to listen is time consuming and costly. In recent years more objective methods have been developed to measure the MOS. For these methods one injects reference audio from a source file (the ‘reference file’) recorded from a speaker and then captures the resulting audio after transmission through at least one RAN in a target file (the ‘degraded’ file.) One can then use software to compare and analyze the reference file and the degraded file to estimate the MOS.
Several software packages are commercially available for automated assessment of speech quality and to provide a perceptual objective listening quality assessment. Example software packages are PESQ and POLQA. PESQ stands for “Perceptual Evaluation of Speech Quality.” It is standardized as ITU-T recommendation P.862. POLQA stands for “Perceptual Objective Listening Quality Assessment” and provides automated assessment of speech quality. It is standardized as ITU-T recommendation P.863.
Voice quality strongly depends on the properties of the Radio Access Networks (RANs) that are being used by the source UE and the target UE. The components making up a RAN (e.g. the source UE and base station) and the air interface that connects them (e.g. the LTE air interface) introduces impairments such as packet losses, packet delays, fluctuations in the packet losses (jitter) and packet errors (frame errors). The RAN may be a RAN of a wide area wireless network that uses GSM, UMTS, GPRS, CDMA or LTE and the like, or the RAN of a local area wireless network such as DECT, Bluetooth, and Wi-Fi and the like. Another contribution comes from the internal components of the network that interconnects the source RAN and the target RAN, as internal components in the wireless system 8 in FIG. 1 . For simplicity these internal components are not shown but may include well-known entities such as one or more base stations (such as LTE Node-Bs), mobile switching centers, regional network controllers, serving and packet gateways, gateway controllers, mobility management entities, the various Call Session Control Functions (CSCFs) of an IP multimedia system such as the Proxy-CSCF, the Interrogating CSCF, and the Serving CSCF and various databases. The wireless system 8 may further contain entities that manage the quality of service, such as a policy charging and rules function.
FIG. 2 shows components used in conventional test systems that emulate the effect of impairments to enable evaluation of one or more RANs in a laboratory environment. The emulation test components of FIG. 2 are provided in the test system 20 which receives signals from UEs in a system otherwise similar to FIG. 1 . The signals transmitted to and from the test system 20 include a reference media signal 1 from the UE 2 and the output includes a degraded media signal 11 provided from a DUT UE 4 . Components carried forward from FIG. 1 , as well as components carried forward in subsequent drawings, are similarly labeled.
The test system 20 includes faders 22 and 28 and components 24 and 26 that emulate two separate RANs 24 and 26 . A fader is a device that emulates the behaviors of an air interface, for example by varying the signal strength of the modulation of the uplink and/or downlink air interface connections. The test system 20 provides a way to produce artificial impairments of a source RAN and a target RAN by emulating each RAN with a signaling tester (like an Anritsu MD8430), and by imposing artificial impairments on each air interface with a fader (like an Anritsu MF6900A.)
To estimate a MOS using the test system 20 of FIG. 2 , one configures the testers and the faders 22 and 28 according to specific RAN parameters. This causes precisely controlled losses, delays, jitter and frame errors on the air interfaces. Next a call is started between the source UE 2 and the target UE 4 and a user plays the sound from a reference media file 1 into the source UE 2 , for example via the source UE 2 built-in microphone or via the source UE 2 microphone jack. The sound is then captured at the target UE 4 from its built-in speaker or headset jack, and converted to digital data and stored as a degraded media file 11 . PESQ or POLQA is finally used to compare and analyze the files and to obtain the MOS. Note that the same system in a slightly different configuration may be used to obtain a MOS for multimedia transmission from the DUT UE 4 to the peer UE 2 .
Operators need to measure the impact on the MOS of the various parameters that control the air interface so that they can optimize throughput without degrading voice quality. What is needed is a method that can automatically evaluate the MOS for a UE for a voice call that involves a source RAN and a target RAN under various RAN conditions without the cost of expensive equipment such as the faders in shown in FIG. 2 .
SUMMARY
Embodiments of the invention provide an automated method to estimate a Mean Opinion Score (MOS) for a Device Under Test (DUT) using inexpensive test components. The test system uses a server computer to eliminate the need for faders and other test equipment conventionally used. The server computer manipulates data packets from the reference media file to simulate noise and jitter at a much lower cost than using actual faders. The server computer also uses software to provide a solution for automated assessment of the speech quality as experienced by a user of a wireless telephony system. The server computer provides the automated assessment with software that performs a perceptual objective listening quality assessment by a standardized methodology such as PESQ or POLQA or similar procedure known in the art. The system may assess the media quality for media transmitted over the air interface in the downlink direction (towards the DUT) and/or transmitted in the uplink direction (from the DUT).
The test system server can estimate media quality for voice and for video media. The computer creates a simulated reference speech or video sample that is extracted as a reference media file and converted into a Voice over IP (VoIP) packet stream. Artificial impairments are imposed by the server computer on individual packets in the stream of packets to simulate the impairments that are typical during transmission over one or more wireless Radio Access Network(s) (RANs). The impairments introduced simulate impairments created by the air interfaces 6 , 10 or radio frequency (RF) links as well as a wireless connection system 8 that can cause the order of packets received to be delayed or changed so that the order of packets must be changed back upon reception by a target peer media device DUT to maintain the correlation between consecutive packets and prevent voice signal disruption. The impairments introduced can also simulate a dropping of a first individual packet that causes a delay in transmission of a second individual packet, a condition that causes packets to bunch up which will affect voice quality. The system can introduce the impairments using a simulated source peer media device for the UE 2 , enabling simulation of transmission through two separate RANs by two parties communicating using separate mobile devices (an end-to-end test solution) with a single cell phone.
In the test system, an operator can vary the parameters for the impairments in the first and second RANs and investigate its effect on the DUT and the media quality. This allows for rapid characterization of the DUT, or, conversely, an efficient way to optimize the configuration of the RANs.
The server computer transmits the stream of packets with these impairments over a wireless connection to and from the DUT. In the downlink test direction the audio signal that represents the stream of packets is received back from the DUT and is captured back into the server computer, e.g. by using a sound card, and converted into digital audio to form a degraded media file. The degraded media file and the reference media file are then compared and analyzed to obtain the MOS in the server computer.
In some embodiments the test system can be run in the uplink direction. In this direction, the server computer transmits a reference audio signal to the DUT UE 4 through an internal or external sound card using a speaker to transmit to the DUT microphone or a cable from the sound card to the DUT earphone connection. The DUT then converts the audio signal into a stream of packets, which are transmitted over the air interface in the uplink direction through a test system back to the server computer, which captures the stream of packets into a degraded media file for evaluation.
In another embodiment the test system can provide and analyze video signals. The video signals can be projected from the server computer and received by a video camera of the DUT. The DUT can then packetize the video signals and transmit them as a stream of packets through a test system back to the server computer, which captures the stream of packets as a degraded media signal for evaluation. In yet another embodiment both the audio and video signals can be transmitted and evaluated.
The test solution of embodiments of the present invention can, thus, provide the following features: (1) an independent simulation of a source RAN, target RAN and the network that connects the RANs; (2) a solution that manipulates data packets to simulate losses, errors, noise and jitter by introducing impairments while controlling a correlation between the impairments imposed on consecutive packets; and (3) a solution that enables simultaneous estimation of an end-to-end MOS and the contribution to the total MOS from a single DUT.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details of the present invention are explained with the help of the attached drawings in which:
FIG. 1 illustrates the classic test system to measure voice quality in a wireless system;
FIG. 2 shows components used in conventional test systems that emulate the effect of delay and jitter to enable evaluation of one or more RANs in a laboratory environment;
FIG. 3 shows components of a RAN that can be simulated to include embodiments of the present invention;
FIG. 4 shows the arrival of packets, the assignment of sequence numbers (1, 2, 3 . . . ), and the distribution of the packets within the RAN of FIG. 3 ;
FIG. 5 shows how the test system setup of FIG. 3 can be modified when components according to the present invention are used;
FIG. 6 is a flow chart illustrating an example implementation of a RAN impairment simulation;
FIG. 7 shows a flow chart illustrating chaining two RAN simulations;
FIG. 8 shows a flow chart illustrating how the test system may also simulate impairments in the network between two RANs;
FIG. 9 is a timing diagram illustrating that the network delay simulation may cause voice frames to be delivered out of order;
FIG. 10 shows modification of the block diagram of FIG. 7 to add in simulation of a network between source RAN and the target UE;
FIG. 11 shows an example simulation where the network has introduced impairments to the packets released from the network simulation of FIG. 9 and the test system passes the packets to the target RAN where further impairments are added by the target RAN;
FIG. 12 illustrates how the test system can chain a source RAN simulation with a network simulation and a target RAN simulation;
FIG. 13 shows modifications to FIG. 12 to produce a simulated degraded test media to enable analysis of effects introduced by the target DUT;
FIG. 14 shows the software components of the revised test system to enable the simulation of RAN and/or network impairments in a non-real time;
FIG. 15 shows a block diagram of components making up a test system according to the present invention;
FIG. 16 provides more details of the block diagram of FIG. 15 showing components used in a downstream communication path; and
FIG. 17 provides more details of the block diagram of FIG. 16 showing components used in an upstream communication path.
DETAILED DESCRIPTION
FIG. 3 shows components of a RAN 300 to illustrate signals that are transmitted and received over a typical LTE network. The system of FIG. 3 will enable a subsequent explanation of how a server computer in the test system according to the present invention can manipulate the signals to simulate noise and jitter. FIG. 3 illustrates the operation of various protocol layers that impact voice quality in an LTE RAN. For simplicity it only shows the Radio Link Control (RLC) layer and the Media Access Control (MAC) protocol layers.
For a source RAN, the transmitting entity is the source UE and the receiving entity is the base station. In the target system those roles are reversed. Only operation in Unacknowledged RLC Mode (UM) will be discussed, since that mode is typically used for voice and video. Details of the MAC and RLC operation can be found in 3GPP Technical Specification (TS) 36.321 and TS 36.322 respectively.
The transmitting entity 302 receives data at a Server Access Point (SAP) in the RLC layer. The source UE sends the SAP signals that are received as a stream of media frames which are encapsulated in RTP IP packets. This is commonly referred to as Voice over IP (VoIP). The voiced packets originate at the source UE at regular intervals (20 ms for the AMR-WB encoded voice). The time stamp in the RTP packets represent the time of the encoding. The RLC Segmentation layer 304 performs segmentations and assigns sequence numbers. For voice there typically will be one RTP packet per segment. The RLC Segmentation layer passes the packets to the transmitting MAC entity 306 which transmits the packets over the air interface to the MAC verification entity 314 of the receiving entity 312 . The MAC layer 306 , 314 uses Hybrid ARQ and returns an Ack or Nack to indicate whether the transmission succeeded. A Nack causes the transmitting MAC entity 306 to retransmit the packet. A packet can be lost if the maximum number of retransmissions is reached or when a Nack indication is corrupted and interpreted as an Ack.
Since the effective number of retransmissions is different for different packets, they may be received by the MAC verification entity 314 in the wrong order. The RLC receiver entity 316 will re-order such packets by waiting for packets that come late. The maximum waiting time is controlled by a T_reorder timer in the software of the RLC receiver 316 , so that the RLC 316 will not wait forever when a packet is lost. Once packets are received and ordered, the RLC 316 will then transmit them out through a SAP. Operation in the target RAN is similar to the receiver RAN 300 , except that the packets may not arrive at a regular clip.
FIG. 4 shows the arrival of packets at the SAP input to RLC 304 in transmitting entity 302 with an assignment of sequence numbers (1, 2, 3 . . . 9) in the first line, and the distribution of the packets within the RAN 300 of FIG. 3 . The next three lines show the Hybrid Automatic Repeat Request (HARQ) processing in the MAC 306 of the transmitter 302 which handle separate HARQ processes A-C to feed packets to the MAC 314 of receiver 312 . The first transmission of packet # 1 does not succeed and the MAC receiver 314 returns a Nack. The second transmission, or retransmission succeeds, and is indicated by an Ack. Packet # 2 takes more retransmissions, but eventually arrives after four retransmissions, which each taking 8 ms. Transmission of packet # 3 succeeds the first time, so that the RLC receiver gets packet # 3 before it has packet # 2 . In that case RLC 316 starts the reorder timer. It will not release packet # 3 before it gets packet 2 , and it will release the packets in the right order.
FIG. 4 also illustrates what happens when a packet, such as packet # 5 , is lost. When packet # 5 is first not received, the RLC 316 starts the reorder timer when it gets packet # 6 and starts to wait for packet # 5 until the timer runs out. Packet # 6 is shown to arrive late because it took too many retransmissions. This is not unreasonable, given the bad channel conditions that caused the previous packet # 5 to be lost. Such bad channel conditions cause correlation between the losses and delays of consecutive packets. Note that by the time the reorder timer of RLC 316 runs out, several more packets # 8 , # 7 , # 9 have arrived. The RLC 316 will then release the arrived packets in the right order over the SAP.
It is important to realize that losses and delays in the RAN are highly correlated. A loss or a delay of one packet may cause the delay of several other packets. These correlations can seriously impact voice quality and should be properly considered when evaluating a MOS.
Note that although losses of a RAN are dealt with in FIG. 3 , the network that connects the source RAN and target RAN will also introduce additional losses, delays and jitter. It may also add frame errors. When the source UE and the target UE use different codecs, the network will contain transcoders which introduce additional impairments. The impairments of the network connecting two RANs may, thus, also need to be simulated.
RAN Impairment Simulation
FIG. 5 shows how the test system setup of FIG. 2 can be modified when components according to the present invention are used. The configuration of the simplified test system 30 of FIG. 5 still uses one or more signaling testers that emulate the source and target air interfaces, but it does not need faders. In FIG. 5 , the RF link of one or both of the air interfaces can use an ideal configuration that does not add significant losses or jitter. On an ideal RF link, all packets are transmitted with the shortest possible delay and with sufficient RF power to eliminate packet losses. This can be done because all losses and jitter will be simulated instead.
To enable the test system setup of FIG. 5 , the impairments in the source RAN and in the target RAN are simulated in the test system software of a server computer. The RAN impairment simulation is controlled by a number of parameters that are representative for the protocol layers of the RAN, such as the maximum number of HARQ transmissions, M_transmit, and the duration of the RLC reordering timer, T_reorder. The source RAN and target RAN may use different parameter values. Such a RAN simulation may be implemented in many different ways and with different levels of detail.
An example implementation of RAN impairment simulation is illustrated in the flow chart of FIG. 6 . FIG. 6 shows simulation of the Unacknowledged Mode (UM). The simulation is used to delay the real VoIP packets that travel from the source UE to the target UE. The simulation imposes random packet losses (or dropped packets) according to a configured packet loss parameter. For a packet that is not lost or dropped, the simulation will calculate the release time, T_out and the simulation will delay the packet until T_out occurs.
The process begins in step 600 when a VoIP packet is received by the test system in RLC 304 and the packet is tagged with the arrival time T_in. In step 602 the RLC 304 of FIG. 3 assigns a sequence number to the packet. The packets are then passed to MAC 306 and in turn either lost or passed on to MAC 314 . In step 604 the MAC 306 determines if the packet will be successfully transmitted or lost. In step 606 the MAC 314 determines if a packet is received OK or lost. If the packet is lost, the MAC 314 in step 608 remembers the packet is lost until the next packet is processed. If the packet is received OK, in step 610 the packet is released at time T_out to the receiver RLC 316 . T_out takes into account the latency and retransmission from an initial transmission by adding time to the initial transmission T_in. The actual added delay caused by each of 1 . . . M retransmissions along with latency time in LTE amounts to about 2 ms for latency itself plus the retransmission time on the order of 8 ms for each retransmission.
The RLC 316 next begins processing the packets and assuring they are in the correct order in step 614 . In the first step 614 in the RLC 316 a determination is made if the packet is received while the reorder timer is running. If so, in step 620 the packet is held for release till the timer expires. If the reorder timer is not running as determined in step 614 , the process moves to step 616 to determine if a previous packet is lost. If so, in step 624 timing is delayed for the packet so it can be placed in the correct order. If a previous packet has not been lost as determined in step 616 , the process moves to step 618 where it is determined if the packet should be delayed relative to other previous packets. If so, delay is applied in step 622 to ensure packets are properly ordered. If not, in the final step 626 any packets with the same T_out are ordered by increasing sequence number before the packets are passed to the output.
The calculation of the output transmission time T_out in step 610 is controlled by various parameters such as a parameter that specifies which fraction of the packets fails each HARQ transmission (Nack). A typical value of the parameter would be 20% but the simulation can be used with any other value. Note that the simulation algorithm is simpler than the algorithms used by a real MAC and RLC layer. This is because when the fate of a packet is computer-generated, the simulation already knows the fate of all preceding packets.
The calculation of T_out simulates the effect of packet losses, HARQ retransmissions, and reordering and thus precisely replicates the correlations between packet losses and packet delays. More complex simulations incorporate the effects of segmentation (not shown), which may occur in the target RAN when multiple VoIP packets arrive at the same time. In this case multiple VoIP packets may be included in a single MAC PDU which gives rise to additional correlations. The segmentation may also split a large media packet, like a video packet, into smaller segments.
The test system can simulate the impairments in one or more RANs. One way to implement this is to chain two RAN simulations, as shown schematically in FIG. 7 , which shows the chaining of a source RAN simulation 720 and a target RAN simulation 730 . Here the test system first uses a source RAN simulation 720 to calculate a T_out. However, the test system does not release a packet at the T_out, but instead passes the packet to the target RAN simulation 730 . The target RAN simulation 730 may lose the packet or may further delay it, which results in an updated value for T_out.
For more details of the steps in FIG. 7 , the process begins when a packet arrives at T_in at step 700 and is delivered to the source RAN simulation 720 in step 702 . After processing in the source RAN simulation 720 , the packet is released in step 704 at a new T_out. The new T_out from the source RAN simulation 720 is set as the new T_in in step 706 and delivered to the target RAN simulation 730 in step 708 . The target RAN simulation 730 processes the new packet and may lose or delay the packet before releasing the packet at step 710 for being transmitted at a new T_out in step 712 .
The test system may also simulate impairments in the network between two RANs as illustrated in FIG. 8 . The network simulation can provide parameters to simulate the additional packet losses, packet errors, delay and jitter introduced by the network. The process begins in when a packet arrives in step 800 . Random losses or delays are then introduced in step 802 . In step 804 a determination is made if a packet has been lost. If so, in step 806 the system remembers the packet is lost until the next packet in sequence is processed. If in step 804 no packet is lost, in step 808 some packets are marked for a random introduction of a frame error. In step 810 a determination is made if the packet is slated for introduction of a frame error. If so, in step 812 the frame error is injected and in step 814 a T_out transmission time is assigned to the packet with some T_out times having a random delay introduced. If in step 810 the packet is not slated for introduction of a frame error, the system proceeds to step 814 for assignment of T_out with some T_outs receiving a random delay. In step 816 , the packets are released at their assigned T_out.
FIG. 9 is a timing diagram illustrating that the network delay simulation voice frames may be delivered out of order when network jitter is configured to be large compared to the packet spacing. As shown in FIG. 9 , the packet # 1 is actually lost in the network after being released from RAN 1 . Further, packet # 2 is delayed in the network so that it is released to RAN 2 after packets # 3 and # 4 . Additionally, packets # 7 and # 8 are reordered due to delays in the network.
When the source UE and the target UE use different codecs, the network simulation may further provide (real) transcoding. Use of transcoding can introduce further delays. Use of a transcoder typically requires adding a de-jitter buffer, which may be a simulated de-jitter buffer or real one in the test system according to the present invention.
FIG. 10 shows modification of the block diagram of FIG. 7 to add in simulation of a network simulation 1020 between source RAN simulation 720 and the target RAN simulation 730 . In the network simulation 1020 steps 1010 and 1012 are added to account for the network. The source RAN simulation 720 thus releases its packet to the network simulation 1020 as a new packet in step 1010 . The network simulation 1020 then simulates impairments of the network and releases the packets in step 1012 to the target RAN simulation 730 for further steps.
FIG. 11 shows an example simulation after the network has introduced impairments to the packets released from the network simulation of FIG. 9 and the test system passes the packets to the target RAN simulation 730 where further impairments are added by the target RAN simulation. Note that the RLC layer in the target RAN assigns new sequence numbers to the incoming packets (a, b, c, d, e, f, g). The RLC receiver 316 of the network will deliver the packets with increasing new sequence numbers. Thus, if a target RAN receives packets from the network out of the original order (3, 4, 2, 6, 8, 7, 9), the packets will remain out of order as shown.
Because of the HARQ retransmissions and RLC reordering, there is a strong correlation between the impairments of consecutive packets. For example, if a packet is delayed significantly, the next packet will be late as well (e.g. packets e and f relative to packet c in FIG. 11 ) and if a packet is lost, the next packet will be delayed (e.g. packets d and e). FIG. 11 also shows that packets tend to become bunched together. It is important to simulate the details of this bunching, because bunching seriously impacts voice quality, particularly when a large bunch of packets is lost in a de-jitter buffer. Prior art tools do not simulate correlations between the impairments of consecutive packets, and do not reveal the effect of bunching on voice quality.
FIG. 11 illustrates that operation of the target RAN is otherwise similar to the source RAN illustrated in FIG. 4 . The MAC transmitter 306 has multiple HARQ processes. The packet b takes one retransmission in process B before arriving. The RLC receiver 316 then must reorder packets b and c. Packet e requires three retransmissions before arriving. Packets e, f and g must then be reordered by the RLC receiver using the reorder timer.
Single UE Test System Operation
FIG. 12 illustrates how the test system can chain a source RAN simulation 720 with a network simulation 1020 and a target RAN simulation 730 while using only one real DUT UE 4 . The test system 1200 , which can be included in a single server computer, can include software to generate the entire simulation chain and the source UE 1202 . The system can store recorded or computer-generated reference media 1 and simulate a UE 1202 , the first simulated RAN 720 , the connecting network 1020 and the second simulated RAN 730 . The target RAN simulation 730 may or may not use the same protocol rules as the source RAN simulation 720 illustrated in FIG. 6 , and it may use different values for RAN parameters like T_reorder. To accomplish the chaining, the T_out of the first RAN simulation 720 is used as T_in for the network simulation 1020 , and the T_out of the network simulation 1020 is used as the T_in of the second RAN simulation 730 . Packets that are not lost in the simulations are released at the T_out over the air interface after the second RAN simulation 730 by a signaling tester (not shown). The signaling tester can be a simple one that emulates an ideal air interface that does not introduce further impairments or fading.
To estimate a MOS in this setup, the test system is configured to provide the ideal air interface and the source RAN simulation 720 , the network simulation 1020 and the target RAN simulation 730 are configured to produce artificial impairments. To begin the testing process a call is started between the simulated source UE 1202 and the target DUT UE 4 and sound is played from a reference file into the codec of the simulated source UE 1202 . The sound may be represented by digital data, such as PCM. The codec runs in encoder mode to produce VoIP packets that are presented to the source RAN simulation 720 which is chained to the target RAN simulation 730 . These simulations delay the VoIP packets before they are transmitted over the air interface to the real DUT UE 4 . The DUT UE 4 uses the codec in decoder mode to obtain first a digital representation of the sound, such as PCM. The DUT UE 4 may then use a digital-to-analog converter (DAC) to produce analog sound. The resulting sound that represents the stream of packets is captured at the Audio/Video port of the Server PC 1500 , digitized, and stored as a degraded media file 11 . PESQ or POLQA or a similar procedure can finally be used to compare and analyze the reference and degraded files to obtain the MOS.
There are alternative ways to produce the degraded file 11 for evaluation. In one alternative, the digital result of the UE 4 's decoder is a stream of packets that is captured by the UE 4 in an internal degraded file. That degraded file can later be captured from the UE 4 by the server PC 1500 , for example over the air interface or over the UE 4 's Universal Serial Bus (USB) interface. In another alternative, the decoder's digital output is streamed out of an interface of the UE 4 (e.g. USB) and captured externally on another computer or on a memory stick as the degraded file 11 . A disadvantage of these alternatives is that the sound path does not include the analog audio components in the UE 4 .
The MOS determined with the system of FIG. 12 reflects the total degradation of the entire path from the reference file 1 delivered to the source UE 1202 to the audio output of the target UE 4 . Presumably the MOS is dominated by the artificial impairments introduced in test system 1200 . One can determine the contribution to the degradation of the target UE 4 , by making a copy of the voice packets before they are sent over the air interface as shown in FIG. 13 .
FIG. 13 modifies FIG. 12 to add a computer generated simulated DUT 1310 from the output of the target RAN 730 to produce a simulated degraded test media 1312 to form new test system 1300 . The output of target RAN 730 is still also passed over an air interface to a real target UE DUT 4 . The voice packets are then processed by both the second simulated UE 1310 and the real DUT 4 . The second simulated UE 1310 provides a de-jitter buffer and a codec to decode the impaired voice packet. The impaired packets are presented to the second simulated UE 1310 at their respective simulated T_out times and the output of the decoder is captured in a file which is called the degraded test media file or intermediate media file 1312 . To determine the contribution of the UE, one uses PESQ or POLAQ or the like to compare and analyze the intermediate file with the degraded file captured at the target UE. This way one can determine, for example, how deep the de-jitter buffer is in the UE 4 .
The components shown in FIG. 13 enable an alternative embodiment of the present invention. This embodiment estimates a MOS for a combination of impairments of two target DUTs 4 and 1310 . The system enables optionally determining impairments of the simulated connecting network 1020 both with the impairments of the real DUT 4 and without target DUT 730 impairments in DUT 1310 to enable identification of the effect of impairments introduced by the DUT UE 4 by comparing the degraded media 11 with degraded media 1312 , for example by the use of PEQ or POLQA.
Non-real Time Operation
The RAN simulation algorithm illustrated in FIGS. 4 and 11 are such that packets are presented to the simulation in order of increasing T_in. Thus, when the network simulation changes the packet order, the packets should be sorted or reordered by increasing T_in before they are passed to the next RAN simulation. Otherwise, as illustrated in FIG. 11 , the packets, like 2, 3 and 4, remain reordered as 3, 4 and 2.
The need to reorder packets increases the complexity of the simulation, because new packets continue to enter into the simulation while the reordering is taking place. These new packets may impact the final packet order, and require functionally that is akin to a de-jitter buffer. The complexity of the reordering can be reduced by running the simulation in non-real time. In this non-real time mode, sorting or reordering can be provided at each air interface simulation that would otherwise introduce a non-real time component.
The software components of the revised test system 1400 to enable the sorting in a non-real time simulation are illustrated in FIG. 14 . Sorting steps 1410 , 1412 and 1414 are introduced in test system 1400 after each of the source RAN simulation 1206 , network simulation 1208 , and target RAN simulation 1210 . If a simulation step changes the order of the frames, the packets are sorted in a sorting step after the simulation step is finished. The packets are sorted by increasing T_out. The result of this cascade of simulations and sorts is then captured or stored in a memory like a random access memory or a hard drive as an impaired media file before it would be sent over the air interface. For each packet, the simulated T_out is recorded as well. To complete the MOS estimation, the test system 1400 plays out the stored impaired media in real time by transmitting each stored packet in real time at the T_out resulting from the cascaded simulation via the signaling tester over the air interface with the DUT UE 4 . Note that in this case T_out is referenced with respect to the beginning of the real-time play-out.
The non-real time preparation does not only simplify the reordering of out-of-order packets. It also reduces the computational load on the test system while the packets are being transmitted to the DUT. The computational load can be reduced for MOS evaluation of uplink media by capturing all uplink packets in an intermediate file and by ordering and converting the packets after all packets corresponding to the reference file have been transmitted over the air interface. The stream of packets is thus produced in non-real time, stored and played out later in real time.
Proposed Implementation
FIG. 15 shows a block diagram of components making up a test system according to the present invention. The components used in the test system are included in the ME7834 Test Platform available from Anritsu Company, but does not include faders. The platform includes a server PC 1500 with a user interface, a test control PC 1502 , a signaling tester 1508 , and a DUT UE 4 . The signaling tester 1508 can include the MD8480, MD8470 and MD8340 test devices available from Anritsu Company. These signaling testers function similar to a base station in a mobile telephone system, and in particular the MD8340 emulates an LTE system base station. The server PC 1500 includes a sound card that can connect to a speaker and microphone or to the UE DUT 4 headset/microphone jack with audio and video ports to enable testing with a DUT UE 4 . The server PC 1500 also includes a packet data signal port for testing IP Multimedia Subsystem (IMS) functionality that provides SIP messaging, voice, video and other data signal capabilities over LTE. Finally, the server PC 1500 includes software for media quality evaluation and for estimation of a MOS. The test control PC 1502 and the server PC 1500 may be implemented on a single computer.
The test system shown in FIG. 15 typically provides for testing of basic functionality over LTE. The system emulates an air interface that is essentially lossless and has a fixed latency and does not use or apply faders. The implementation according to the present invention extends the implementation of the existing test system product. The present invention extends the system by modifying the software in the server PC 1500 to implement the test simulation process described herein.
FIG. 16 provides more details of the block diagram of FIG. 15 showing components used in a downstream communication path. FIG. 16 also shows details of the control PC 1502 . The functionality of the IMS is distributed between the control PC 1502 and the server PC 1500 . The main task of the IMS is to set up a call between a simulated or “virtual” source UE provided by from the server PC 1500 and the DUT UE 4 . The server PC 1500 simulates a media gateway and handles all voice, messaging and broadband media data as coordinated by the control PC 1502 . The server PC 1500 further simulates a “virtual” source UE 1504 that communicates VoIP with the target UE DUT 4 through signaling tester 1508 .
For downlink VoIP, the server PC 1500 provides a reference media signal, for example by reading an audio file or a video file from a Compact Disc (CD) of from a hard drive. The server PC 1500 converts the digital media signal from the reference media file with a codec; encapsulates the resulting voice frames into Real Time Transport Protocol (RTP) and sends the RTP packets as a stream of packets through a packet data output port to the test port of the signaling tester system 1508 . The reference media file created is also stored in a memory as a reference digital media file for later analysis. The signaling tester 1508 applies Robust Header Compression (RoHC) for LTE signal transmission and schedules the packets for transmission over the downlink RF air interface. The DUT UE 4 receives the packets; applies RoHC decompression; decapsulates the resulting RTP packets and decodes the resulting voice frames with the appropriate codec to obtain audio. The DUT UE 4 outputs an audio representation of the stream of packets via its speaker or via a headset jack back to server PC 1500 .
The server PC 1500 can use a sound card 1600 to handle the analog audio of the DUT UE 4 . The sound card 1600 receives analog audio from the DUT UE 4 and applies it to a codec that converts the audio back to a digital media signal (PCM). Although a sound card is shown, other components known in the art can be used to transmit audio such as a direct cable connection through an earphone audio jack or other wireless connection that allows the audio signal to be transmitted such as through a speaker and microphone system or over Bluetooth between the DUT UE 4 and server computer 1500 . In subsequently described embodiments, a video signal can similarly be transmitted directly between the server PC 1500 and DUT UE 4 , effectively providing a digital “media” signal connection possibility. The digital media signal can be transmitted in both an uplink direction and a downlink direction as described subsequently. The digital media signal in the downlink direction transmitted in audio form from the DUT UE 4 to the server PC 1500 is then stored in a file called the “degraded media file” that will be compared with a “reference media file” created by the “virtual UE” and stored in memory in the server PC 1500 for determination of audio quality using MOS.
The server PC 1500 simulates the RAN and network impairments under control of Rapid Test Designer (RTD) software provided in the test control PC 1502 . The RTD software of the test control PC 1502 can specify to the server PC 1500 the impairment values that are to be applied. To simulate impairments, the server PC 1500 first generates downlink media packets (which are also stored in a memory in the PC 1500 as a reference audio file) and then encodes them using a codec to provide a source audio file at the precise specified rate. The server PC 1500 then applies the specified impairments by removing a fraction of the packets according to the frame loss rate; introducing voice frame errors in some of the remaining packets according to the frame error rate; and by delaying the remaining packets according to the specified parameters. The data is transmitted through the packet data port as a stream of packets from the server PC 1500 to signaling tester 1508 .
The DUT UE 4 captures the stream of packets from the signaling tester 1508 . The DUT 4 then in the downstream direction creates a media signal from the stream of packets. The media signal created from or derived from the stream of packets by the DUT is then provided to the server PC 1500 , for example by playing an audio file through a speaker to be received by a sound card 1600 of the server PC 1500 . The server PC 1500 captures the media file and obtains a MOS by using POLQA or similar evaluation technique know in the art to compare the contents of the source file (the “reference media file”) with the file captured from its sound card 1600 as received from the DUT UE 4 (the “degraded media file”). POLQA also estimates the delay between the audio in the reference file and the degraded file.
More details of operation of components of the system of FIG. 16 , particularly involving the test control PC 1502 , are as follows. First, more details of the test control PC 1502 are that it includes a RTD system to control the IMS test signal generation and transmission components, the systems being controlled including the server PC 1600 , the signaling tester 1508 and the DUT UE 4 . The RTD instructs the server PC 1500 which reference file is to be used as audio source. The RTD also provides parameters that specify how the downlink VoIP is to be impaired in the server PC 1500 . After the DUT UE 4 attaches to LTE and registers with the IMS of the test platform 1508 , the RTD initiates the call by instructing the server PC 1500 to let the virtual UE send a SIP INVITE to the DUT UE 4 . The RTD then controls the remainder of the call setup.
Once call setup is complete, the more details of the audio path that is initiated are as follows. First, after setup completion is acknowledged, the server PC 1500 starts the playout of the reference audio file from its internal virtual UE into the codec. The server PC 1500 then encapsulates the voice frames from the codec in an RTP stream of packets and applies the specified impairments before sending the RTP packets to the DUT UE 4 via the signaling tester 1508 . The analog audio output of the DUT UE 4 is equivalent to the stream of packets and is applied to the sound card 1600 . The server PC 1500 then captures the resulting degraded audio and produces the degraded audio file. The server PC 1500 then informs the RTD in the test control PC 1502 . The RTD ends the call by instructing the server PC 1500 to send a SIP BYE message. The RTD also instructs the server PC 1500 to perform a voice quality comparison by running POLQA on the audio files to estimate a MOS and the measurement results are passed to the RTD. For improved statistics, the test system may repeat the above procedure using the same reference media signal, or may repeat it using different reference files. Optionally, several files can be processed during a single call.
In one embodiment of the present invention, the simulated impaired packet stream is saved in memory as a first reference media file. A copy of the first reference media file is then provided through an internal de-jitter buffer that simulates an ideal DUT UE, such as the component 1310 in FIG. 13 . The simulated DUT UE RTP output is then decapsulated and the resulting voice frames are decoded to produce a second degraded media file. The server PC 1500 can run the POLQA to compare and analyze the first and the second degraded files to estimate the contribution to the quality degradation that comes from the DUT UE 4 .
In another optional embodiment of the present invention, the server PC 1500 can be configured to test the DUT UE under high loading conditions. To create high loading conditions the server PC 1500 can send additional packets to the target UE 4 . The server PC can also create high loading conditions by sending control signals to force the target UE 4 to send uplink packets while the MOS test is in progress. This allows for evaluation of the MOS under high load conditions.
Although audio signals are primarily described in the test process for the media signals being tested above, video signals or a combined video-audio signal can likewise be tested in the downlink direction using the system illustrated in FIG. 16 . For testing of video signals, the server PC 1500 creates a stream of video packets from a reference video signal, applies impairments and sends the signals over the RF air interface via signaling tester 1508 . The DUT 4 de-jitters and decodes the stream of packets and plays the video images that are the equivalent to the stream of packets on a screen. The screen typically is the display screen of the DUT. The server PC 1500 then uses a camera to capture the analog video images created from or derived from the stream of packets by the DUT 4 and converts them to digital data to apply to a video in port, possibly using a video capture card. The received camera data is then used to provide the degraded media signal. Alternatively, the server PC 1500 may capture the degraded media by obtaining the degraded media signal in digital form directly from the DUT, for example via a USB connection.
In another embodiment, the present invention can be configured to evaluate the MOS for voice communications in the reverse, uplink direction. FIG. 17 provides more details of the block diagram of FIG. 16 showing components used in an upstream communication path. To accomplish upstream communication, the server PC 1500 obtains or creates a reference audio file and stores it as the reference media audio/video file in memory. Instead of converting the reference file to packets and transmitting it to the signaling tester 1508 , the server PC 1500 instead for the uplink media signal converts the audio reference file into an analog audio signal that is the equivalent of the stream of packets using the sound card, which in turn injects the sound via a speaker or headset connector cable to the DUT UE 4 . The DUT UE 4 will convert the audio to a packet stream and transmit the stream over the RF air link via the signaling tester 1508 back to the server PC 1500 . The server PC 1500 will capture the stream of packets and can then impose artificial impairments to simulate effects of the one or two RANs as well as the interconnecting network, decode the packet stream and store the resulting degraded media signal in memory as a degraded file for MOS estimation. Alternatively, the server PC 1500 may inject the reference media signal in digital form directly into the DUT UE 4 , for example via a USB connection. The server PC 1500 may, for example, inject the reference audio signal in PCM format. The DUT UE 4 will then convert the injected audio to an RTP packet stream and transmit the stream over the RF air link.
In another embodiment, instead of audio in the reverse uplink direction, a video signal can be tested in the uplink direction. To accomplish this, an analog video signal image is displayed on a screen (not shown) by a projector of the server PC 1500 . The screen may also be a monitor screen attached to server PC 1500 . The DUT UE 4 then uses a video camera to record the video signal. The recorded video signal is converted to a packet signal by the DUT UE 4 and transmitted through the signaling tester 1508 back to the server PC as a RTP stream of packets. The server PC 1500 then captures the stream of packets and compares the degraded video signal received with the reference video signal it projected to the DUT UE 4 to analyze the media quality degradation. Alternatively, the server PC 1500 may inject the reference video signal in digital form directly into the DUT, for example via a USB connection.
In a further embodiment, both audio and video can be transmitted in the uplink direction as a combined analog media signal. Both the audio and video can then be recorded by the DUT UE 4 and transmitted in packet form back to the server PC 1500 for evaluation. The audio signal can be evaluated by MOS, while the video can be evaluated by a similar procedure known in the art to compare the reference video and degraded video signal to analyze the video signal degradation.
Although the present invention has been described above with particularity, this was merely to teach one of ordinary skill in the art how to make and use the invention. Many additional modifications will fall within the scope of the invention, as that scope is defined by the following claims. | An automated method for testing audio signal quality of cell phone transmissions provides a Mean Opinion Score (MOS) output using inexpensive test components. The test system uses a server computer to eliminate the need for expensive faders used in a bench test system. The server computer manipulates data packets from the reference media file to simulate impairments, including losses, errors, noise and jitter, at a much lower cost than using actual faders. Transmission through two separate radio access networks RANs is provided to simulate two parties communicating using separate mobile devices (an end-to-end test solution) with a single cell phone. | 7 |
This invention relates to connectors for securing members together under large clamping forces and, though more generally applicable, is particularly advantageous for connecting members of an underwater well installation under conditions requiring that the connection be made up by operations carried out from a location remote with respect to the well installation.
RELATED APPLICATIONS
Subject matter disclosed in this application is also disclosed and claimed in copending applications Ser. No. 327,449, filed concurrently herewith by James H. Owens, III, and Ser. No. 327,445, filed concurrently herewith by William S. Cowan and Edward M. Galle, Jr.
BACKGROUND OF THE INVENTION
The need for developing large clamping forces in connectors for securing two members together has long been recognized. Providing large clamping forces is especially important when the connector is to be used for connecting two tubular members of an underwater well installation, since the connection must then withstand not only large forces resulting from component weight and the actions of waves and currents but also large internal fluid pressures. All of the successful prior-art connectors employed in the underwater well field for developing high clamping forces appear to employ annular locking means, varying from annularly arranged locking dogs to a single split locking ring, the locking means being carried by one of the members to be connected and having a frustoconical locking shoulder to engage with a mating shoulder carried by the other member. Opposed transverse end surfaces are provided, and the effect of the locking means, when actuated, is to clamp the end faces together, the locking shoulders providing a strong wedging action to generate the clamping force. In such connectors, actuation of the locking means is accomplished by rectilinear power devices which act in a direction generally axially of the connector. To convert the action of the power devices into effective movement of the locking means, it has become a standard practice to have the power device force a driving ring axially relative to the connector, the driving ring having a frustoconical camming face which slidably engages the locking means to force the locking means generally radially and thus cause the desired wedging action at the locking shoulders. Connectors of this general type are described, for example, in the following U.S. Patents:
U.S. Pat. No. 2,962,096, Knox
U.S. Pat. No. 3,096,999, Ahlstone et al
U.S. Pat. No. 3,228,715, Neilon et al
U.S. Pat. No. 4,200,312, Watkins.
Particularly in the case of underwater well connectors, the difficulties encountered in achieving satisfactory connections are increasingly severe. Such connectors have always been required to withstand both large internal fluid pressures and great, frequently transient, external forces. However, with installations of wells occurring at ever-increasing water depths, and with wells exhibiting increasing large internal pressures, the forces tending to make the connection fail continue to increase. Thus, underwater wellheads are now being required to withstand and seal against internal pressures as high, e.g., as 15,000 p.s.i., and water depths for such installations are now likely to be measured in thousands of feet, so that forces applied to the connector via, e.g., a riser are correspondingly larger. Prospective users of such connectors therefore present increasingly severe specifications for the connector, and the requirements of such specifications prove difficult to meet, so there is an increasing need for improvement of connectors of this general type.
It has been recognized that, in such connectors, it is desirable to place the mating surfaces of the two members to be connected under a large compressive preload, advantageously just short of the yield point of the metal. The preload is established by first engaging the frustoconical locking shoulders and then continuing to supply a large actuating force to the locking means to create a very strong wedging action between the locking shoulders. Success of this action is limited by the adverse effect of sliding friction under the great pressures required, and the desired large compressive preload has frequently not been achieved in practice despite the use of large actuating motors. As disclosed in aforementioned application Ser. No. 327,449, a remarkable improvement in the efficiency of such connectors can be achieved by employing rolling antifriction elements between the camming surface of the driving ring and the cam follower surface of the locking means. However, provision of connectors including the antifriction elements has been difficult to achieve in commercially acceptable form.
OBJECTS OF THE INVENTION
A general object of the invention is to provide a connector of the type described which, though capitalizing on reduced friction provided by rolling antifriction elements during the final stage of actuation, during which compressive preload is established, requires only low power actuation preliminary to establishment of the preload.
Another object of the invention is to devise such a connector which, though providing large clamping forces and establishing a high and persistent compressive preload, requires only relatively small power devices.
A further object is to provide a connector of the type described which makes it possible to employ very small camming angles for actuating the locking means, yet does not require that the driving ring be moved through an especially long travel.
Yet another object is to devise such a connector which has a very high mechanical advantage.
A still further object it to provide a connector of the type described which accomplishes a final stage of operation with the aid of rolling antifriction elements, yet is axially compact and of relatively simple construction.
Another object is to provide such a connector characterized by a low power preliminary operating stage, which accomplishes initial engagement of the locking shoulder, and a subsequent high power operating stage, which establishes a high clamping force, the two stages of operating being accomplished remotely and in automatic succession.
SUMMARY OF THE INVENTION
Connectors according to the invention include an annular locking means which presents an annular locking shoulder, the locking means being radially distortable between an inactive position and an active position and being biased resiliently toward the inactive position. The locking means can be a resilient metal split ring, which is particularly advantageous, or an annular assembly of arcuate segments, or an annular series of locking dogs. Operation of the locking means is accomplished by two actuating means, the first comprising a resiliently expansible and contractible annular member which telescopically engages the locking means and is movable axially relative to the connector between a first position, in which the locking means is allowed to assume its inactive position, and a second position. The locking means has a first frustoconical surface which coacts with a second frustoconical surface on the annular member of the first actuating means in such fashion that, when the annular member is moved axially to its second position, the locking means is radially distorted through most of its excursion from its inactive position toward its active position. The annular member also has a third frustoconical surface which faces away from the locking means and tapers in the same direction as the first and second frustoconical surfaces but at a smaller angle. A second actuating means is employed and includes a rigid driving ring having a fourth frustoconical surface, that surface constituting a camming surface facing the third frustoconical surface and tapering in the same direction and at the same angle. A plurality of rigid rolling antifriction elements are disposed between and in rolling engagement with the third and fourth frustoconical surfaces. The driving ring is disposed for movement between a first position, in which the annular member of the first actuating means can occupy its first position, and a second position, movement of the driving ring from its first position to its second position causing the third and fourth frustoconical surfaces and the rolling antifriction elements to coact to resiliently distort both the annular member of the first actuating means and the locking means to an extent which causes the locking means to complete its travel to its full active position. Operation of the first actuating means if thus effective to accomplish most of the necessary radial distortion of the locking means through the camming action of directly engaged frustoconical surfaces, but since this operation only moves the locking shoulder into initial engagement with the mating shoulder, the sliding friction involved is relatively small and only relatively low power is necessary to operate the first actuating means. Completion of the radial distortion of the locking means is accomplished by the second actuating means and requires the high power necessary to establish the desired large clamping force and compressive preload. This operation is accomplished by coaction of the driving ring and the annular member of the first actuating means through the rolling antifriction elements, so that the losses due to friction are held to a practical minimum and a larger clamping force can therefore be established at a lower power requirement. Advantageously, the first and second actuating means include separate sets of rectilinear power devices, those for the first actuating means being less powerful than those for the second actuating means.
IDENTIFICATION OF THE DRAWINGS
FIG. 1 is a fragmentary vertical sectional view of a connector according to one embodiment of the invention as employed for connection of two wellhead bodies of an underwater well installation, the locking means of the connector being shown in its inactive position;
FIG. 2 is a fragmentary transverse cross-sectional view taken generally on line 2--2, FIG. 1, power devices for the connector being shown in FIG. 2 but omitted in FIG. 1;
FIG. 3 is a fragmentary top plan view of a split ring constituting the locking means of the connector of FIGS. 1 and 2;
FIG. 4 is a fragmentary top plan view of a split ring forming part of the first actuating means of the connector;
FIG. 5 is a fragmentary top plan view of a driving ring forming part of the second actuating means of the connector;
FIG. 6 is a fragmentary side elevational view taken generally as indicated by line 6--6, FIG. 5;
FIGS. 7 and 8 are fragmentary vertical sectional views similar to FIG. 1 but showing successive stages of operation of the connector;
FIG. 9 is a fragmentary vertical sectional view of an automatic control valve employed in the connector of FIGS. 1-8 to accomplish sequential operation of the first and second actuating means of the connector; and
FIG. 10 is a view similar to FIG. 1 of a connector according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The Embodiment of FIGS. 1-9
In the embodiment of the invention shown in FIGS. 1-9, the connector is remotely operated and is employed to connect a wellhead upper body 1, typically at the base of a blowout preventer stack, to a wellhead lower body 2, FIG. 2, in an underwater well installation. Body 1 has a right cylindrical through bore 3 and a transverse annular lower end face, the end face including at its inner periphery a frustoconical seal surface 4 which tapers upwardly and inwardly, an inner transverse portion 5, an outer transverse annular portion 6 spaced outwardly from portion 5, and a frustoconical shoulder 7 which tapers downwardly and inwardly and joins portions 5 and 6. Adjacent the lower end face, body 1 has an integral transverse annular outwardly projecting flange 8, there being an additional frustoconical surface 9 interconnecting the inner periphery of the lower face of flange 8 and the outer edge of surface portion 6.
Lower body 2 has a right cylindrical through bore 10 of approximately the same diameter as bore 3. The upper end face of body 2 includes a downwardly and inwardly tapering frustoconical seal surface 11, an inner transverse annular surface portion 12, an outer transverse annular portion 13, and a downwardly and inwardly tapering frustoconical shoulder 14, the angle of taper of shoulders 7 and 14 being the same. The dimensions of the two end faces are such that the downwardly directed surfaces at 6 and 7 mate with the upwardly directed surfaces at 13 and 14, respectively. The upper end portion of lower body 2 has a transverse annular outwardly opening locking groove 15 defined by a frustoconical upper side wall 16 which tapers downwardly and inwardly at the same angle as shoulders 7 and 14, a right cylindrical inner wall 17, and an upwardly and inwardly tapering frustoconical lower wall 18. Above groove 15, body 2 has a right cylindrical outer surface portion 19.
Flange 8 of body 1 combines with an annular member 20, of generally L-shaped radial cross section, to define an annular connector body indicated generally at 21. Applying usual connector terminology, upper body 1 and connector body 21 combine to form the female connector member, and lower body 2 constitutes the male connector member.
Proceeding outwardly from its juncture with surface 9, the lower face of flange 8 includes a transverse annular surface portion 22, a shallow annular downwardly opening groove 23, a dependent cylindrical flange 24 the inner surface of which forms a continuation of the outer side wall of groove 23, and an outer transverse annular surface portion 25. Member 20 is an integral piece including an upstanding tubular wall 26 and a transverse annular portion 27 lying in a plane at right angles to the axis of wall 26. The free end of wall 26 is annularly notched to accommodate flange 24 and includes a transverse annular end face 28 in flush engagement with surface portion 25 of flange 8. Member 20 is rigidly secured to flange 8, and thus to body 1, by a plurality of high strength screws 29 arranged in an annular series and including unthreaded portions extending through flange 8 and threaded portions engaged in threaded bores in wall 26. The inner periphery of portion 27 of member 20 includes a right cylindrical surface portion 30 of a diameter larger than the outer diameter of body 2 above groove 15, and two frustoconical upwardly and inwardly tapering guide surface portions 31 disposed to assist in guiding and centering the female connector member as it is lowered, with assistance of a conventional guidance system (not shown), onto the male connector member.
Connector body 21 encloses and supports an annular locking means, indicated generally at 35, a first actuating means comprising a resilient metal split ring 36 and a second actuating means comprising a rigid driving ring 37. In this embodiment, the locking means is a single resilient metal split ring 38, the inner surface of which is made up of a downwardly and inwardly tapering frustoconical locking shoulder 39, a right cylindrical surface portion 40 and an upwardly and inwardly tapering frustoconical surface 41. Surface portion 40 joins the lower edge of shoulder 39 and the upper edge of surface 41. At its bottom end, ring 38 has a flat transverse annular face 42, the inner periphery of which joins surface 41. Shoulder 39 tapers at the same angle as upper side wall 16 of locking groove 15. The outer surface of ring 38 is made up of a frustoconical surface portion 43 which tapers sharply upwardly and inwardly at, e.g., 30°, a slow taper surface portion 44 which tapers upwardly and inwardly at, e.g., 3.5°, an additional frustoconical surface portion 45 which tapers upwardly and inwardly at the same angle as surface portion 43, and a lower slow taper surface portion 46 which tapers upwardly and inwardly at the same angle as does surface portion 44. Shoulder 39 and surface portion 43 effectively combine to form the upper end of ring 37. Surface portion 46 extends to lower end face 42, the corner being chamferred as shown.
Split ring 36 of the first actuating means has an inner surface made up an elongated upper slow taper surface portion 48 which tapers upwardly and inwardly at the same angle as surface portions 44,46 of ring 38, a frustoconical surface portion 49 which joins the lower edge of portion 48 and tapers upwardly and inwardly at the same angle as do surface portions 43 and 45 of ring 38, a slow taper surface portion 50 which tapers upwardly and inwardly at the same angle as portion 48 and joins the lower edge of portion 49, and an additional frustoconical surface portion 51 which tapers upwardly and inwardly at the same angle as portion 49 and joins the lower edge of portion 50. The outer surface of ring 36 is a continuous upwardly and inwardly tapering frustoconical surface 52 which is parallel to surface portions 48 and 50. At its upper end, ring 36 is provided with a radially short transverse annular outwardly projecting flange 53. The upper end of ring 36 presents a flat transverse annular surface 54.
Driving ring 37 of the second actuating means is an integral continuous metal ring having a flat transverse upper end face 56, a right cylindrical outer surface 57, a stepped lower end face made up of outer transverse annular portion 58, intermediate right cylindrical portion 59 and an inner transverse annular portion 60. Inner surface 61 of the driving ring is a frustoconical surface which tapers upwardly and inwardly the same angle as surface 52 of ring 36. The upper end of the driving ring is provided with a radially short transverse annular inwardly projecting flange 62 defining the upper end of inner surface 61 and projecting radially inwardly therefrom. The dimensions of the upper end of the driving ring are such that the upper end of the ring can be freely accommodated by downwardly opening groove 23 in flange 8. An annular end ring 63 is secured to the lower end face of the driving ring, as by screws, ring 63 having a strapped upper surface shaped and dimensioned for flush engagement with bottom surfaces 58-60 of the ring. The lower face of ring 63 is flat and parallel to upper end face 56. An inner peripheral portion of ring 63 projects radially inwardly beyond the lower end of inner surface 61, thus presenting a lower retaining flange opposed to flange 62. The axial length of the driving ring, i.e., the distance from face 56 to the lower face of ring 63, is substantially smaller than the distance from the upper wall of groove 23 to the upper surface of portion 27 of member 20. The axial length of inner surface 61 of ring 36 between flanges 62 and the flange constituted by the inner peripheral portion of end ring 63 is substantially equal to the axial length of outer surface 52 of split ring 36.
For simplicity, surfaces 43, 49, 52 and 61 can be considered as primary active surfaces and will be referred to respectively as first, second, third and four frustoconical surfaces.
Power to operate the connector is provided by a first group of fluid pressure operated power devices 65, FIG. 2, which are of relatively smaller size and form part of the first actuating means, and a second group of relatively larger power devices 66, which form part of the second actuating means. Power devices 65 and 66 are advantageously commercially standard hydraulic rectilinear motors of the piston-and-cylinder type. Smaller motors 65 are arranged in an equally spaced annular series adjacent the outer surface of body 1, the annular series being concentric with the axis of bore 3, the cylinder units of the motors being secured to flange 8 and projecting upwardly therefrom, the piston rods 67 of motors 65 extending downwardly through vertical bores in the flange. Larger motors 66 are similarly arranged in an annular series of larger diameter concentric with the axis of bore 3, the cylinder units of motors 66 being mounted on flange 8 and projecting upwardly therefrom, piston rods 68 of these motors extending downwardly through vertical bores in the flange, as shown. The upper end portion of ring 36 is provided with an annularly spaced series of slots 69 equal in number to piston rods 67. Slots 69 extend radially relative to ring 38, open into a transverse annular inwardly opening groove 69a in the upper end portion of ring 36, the outer wall of the groove being spaced outwardly from the outer ends of the slots. The lower end portions of piston rods 67 project downwardly through the respective slots 69 and terminate in an enlargement constituting a lateral flange 70, each flange 70 being slidably retained in groove 69a by a different one of the slots 69. Thus, ring 36 is supported on flange 8 by piston rods 67 and the cylinder units of motors 65 and can be moved upwardly and downwardly by simultaneous energization of motors 65.
The lower ends of piston rods 68 of motors 66 are rigidly connected to driving ring 37 in any suitable conventional fashion, as by screw threads. Ring 37 is thus supported on flange 8 by motors 66, and motors 66 can be operated to move the driving ring upwardly and downwardly.
When substantially relaxed and undistorted, the diameter of outer surface portion 44 of ring 38 is equal to the diameter of inner surface portion 50 of ring 36 when ring 36 is substantially relaxed and undistorted. When the locking ring 38 is in its expanded, inactive position, inner surface portion 50 of ring 36 slidably embraces outer surface portion 44 of ring 38, both split ring 36 and driving ring 37 then being in their uppermost first positions, as shown in FIG. 1.
A plurality of rigid metal balls 75 are disposed in the space between outer surface 52 of ring 36 and inner surface 61 of the driving ring, all of balls 75 having the same diameter and each of the balls being in direct rolling engagement with both surface 52 and surface 61. The number of balls 75 is substantially less than would be required to fill the space between flange 53 and end ring 63 when rings 36 and 37 are in their first positions.
Upper body 1 is equipped with a metal seal ring 77, FIG. 1, having a right cylindrical inner surface 78 and an outer surface made up of an upper frustoconical surface portion 79 which tapers upwardly and inwardly at the same angle as surface 4 of body 1, and a lower frustoconical surface portion 80 which tapers downwardly and inwardly at the same angle as surface 11 of body 2. Such seal rings are conventional and are releasably retained on body 1 by a plurality of retaining pins, not shown.
With rings 36-38 and balls 75 interrelated as shown in FIG. 1, outer surfaces 43-46 and 52 of ring 38 and 36 constitute cam follower surfaces, and inner surfaces 48-51 of ring 36 and inner surface 61 of the driving ring constitute camming surfaces. Camming surfaces 48-51 of ring 36 coact in direct sliding engagement with the cam follower surfaces of ring 37. Camming surface 61 of ring 36 coacts with cam follower surface 52 of ring 36 only through balls 75, with the balls constituting rolling antifriction elements.
Preparatory to making up the connection between bodies 1 and 2, with body 2 having been installed in an underwater location and with the installation including an appropriate guidance system, body 1, with connector body 21 installed thereon and with the parts of the connector occupying the positions seen in FIG. 1, is lowered with the aid of the guidance system and landed on body 2. So landed, body 1 is disposed with its end face in engagement with the end face of body 2, shoulder 7 of body 1 thus engaging shoulder 14 of body 2. Surfaces 79, 80 of seal ring 77 engage surfaces 4 and 11, respectively, and the seal ring is preliminarily energized as a result of landing body 1. With the end faces of bodies 1 and 2 thus engaged, member 20 of connector body 21 surrounds the upper end portion of body 2 and supports split ring 38 in such alignment with locking groove 15 that locking shoulder 39 of ring 38 is radially aligned with, but spaced outwardly from, upper side wall 16 of the locking groove, so that side wall 16 constitutes a mating shoulder for shoulder 39.
Motors 65 are now operated simultaneously, by simultaneous supply of pressure fluid from a source at the operational base at the surface of the body of water, the pressure fluid being supplied above the pistons of the motors to cause piston rods 67 to drive ring 36 downwardly. As ring 36 descends, ring 38 is restrained against downward movement because it is engaged slidably with the inner peripheral portion of the upper surface of portion 27 of member 20. Accordingly, downward movement of ring 36 cams ring 38 inwardly in two stages to the position seen in FIG. 7. The first stage results from coaction of surfaces 49 and 51 of ring 36 with surfaces 43 and 45, respectively, of ring 38 and brings the slow taper portions 48 and 50 of ring 36 into engagement with the mating surfaces 44 and 46, respectively, of ring 38. The second stage of camming action occurs by coaction of surfaces 48,50 with surfaces 44 and 46, respectively, and cams ring 38 further inwardly into groove 15, with shoulder 39 of the ring then engaging upper side wall 16 of the groove, as seen in FIG. 7. Driving ring 37 remains in its uppermost position throughout the full downward travel of ring 36, but since outer surface 52 of ring 36 and inner surface 61 of the driving ring are parallel upwardly and inwardly tapering frustoconical surfaces and downward movement of ring 36 is essentially vertical, no change occurs in the radial spacing between surfaces 52 and 61. The vertical space between flange 53 and end ring 63 decreases markedly as a result of downward travel of ring 36, but the number of balls 75 is selected so that the quantity of balls employed substantially fills the space between flange 53 and ring 63 only when ring 36 has reached its lowermost second position, seen in FIG. 7.
Motors 65 of the first actuating means can now be deenergized or, alternatively, left energized, and motors 66 of the second actuating means are now all energized simultaneously to move driving ring 37 downwardly to its lowermost second position, seen in FIG. 8. Since balls 75 are constantly engaged between camming surface 61 of the driving ring and cam follower surface 52 of ring 36, and since those surfaces are parallel and taper upwardly and inwardly, the effect of full downward movement of the driving ring is to radially distort the combination of ring 36 and locking ring 38 inwardly. Though locking shoulder 39 of ring 38 was already in flush engagement with mating shoulder 16 at the start of the downward movement of ring 37 (see FIG. 7), the angle of taper of surfaces 52 and 61 is small, e.g., 3.5°, and the inward movement of the combination of rings 36 and 38 caused by the downward movement of the driving ring is accordingly small. But this small additional inward movement of ring 38, caused by the higher power of larger motors 66 and the higher mechanical advantage afforded by slow taper surfaces 52 and 61, results in a very strong wedging action at shoulders 16 and 39 and is effective to establish the desired very high compressive preload on the now-clamped end faces of bodies 1 and 2. Under optimum conditions, wedging engagement of frustoconical surfaces 7 and 14 progresses as the preload is established until, as shown in FIG. 8, surfaces 6 and 13 are also in tight flush engagement. Since shoulders 16, 39, 14 and 7 are all mutually parallel, the compressive force of the high preload is applied in a direction substantially normal to all of those shoulders, and therefore acts primarily in compression without generating a shear component of practical effect. The further wedging action at shoulders 16 and 39 which results from full downward actuation of the driving ring also causes seal ring 77 to be further energized between seal faces 4 and 11, assuring that ring 77 effects a good metal-to-metal seal with bodies 1 and 2 so that fluid under pressure in bores 3 and 10 cannot act between the clamped end faces of bodies 1 and 2.
Since the connector illustrated in FIGS. 1-4 is to be made up at a remote underwater site which is not accessible for direct manual manipulation, it is desirable to accomplish the successive operation, first of motors 65, then of motors 66, automatically. For this purpose, the connector is equipped with an automatic sequencing valve 89, FIG. 9, responsive to the position of ring 36 for applying pressure fluid from a single surface-located source first to all of motors 65 simultaneously and then, when ring 36 has reached its lowermost position, to all of motors 66 simultaneously to energize motors 66 to force the driving ring to its lowermost second position. Valve 89 can be of any conventional type for supplying incoming fluid initially to only a first outlet, then to a second outlet in response to movement of an actuator. For illustrative purposes, valve 89 is shown as comprising an upright tubular body 90 secured to and projecting upwardly from flange 8, the body having two inlet ports 91 and 92 connected in parallel to pressure fluid supply conduit 93, and two outlet ports 94 and 95, port 94 being connected in parallel by conduiting (not shown) to the upper ends of the cylinders of all of the motors 65, and port 95 being similarly connected in parallel to all of the motors 66. The valve includes a movable valve member 96 secured to and operated by a rod 97 which extends downwardly through a bore in flange 8, the lower end of rod 97 projecting downwardly beyond flange 8 and being connected to the upper end portion of ring 36 in the same manner hereinbefore described for piston rods 66 of motors 65. Hence, the vertical position of rod 97, and therefore the vertical position of movable valve member 96, depend upon the vertical position of ring 36. Movable valve member 96 is cylindrical and slidably engaged with the inner wall of valve body 90p and is so dimensioned, and ports 91 and 92 are so located, that movable valve member 96 allows communication between inlet port 91 and outlet port 94 for all positions of ring 36 but allows communication between inlet port 92 and outlet port 95 only when ring 36 is in its lowermost position.
The connector is released remotely by venting the power cylinders of motors 65 and 66 above the pistons and simultaneously supplying pressure fluid below the pistons of all of motors 65 and 66, thereby raising rings 36 and 37 simultaneously to their uppermost or first positions. Alternatively, motors 66 can be energized first, to raise driving ring 37, and motors 65 then energized to raise ring 36. With rings 36 and 37 in their uppermost positions, locking ring 38 is free to expand resiliently to its normal relaxed inactive position. Expansion of ring 38 to its relaxed position withdraws the ring from locking groove 15 and thus frees body 1 and connector body 21 for upward withdrawal. Should ring 38 not expand freely when rings 36 and 37 are raised, applying an upward strain on body 1 will cause surfaces 16 and 39 to coact in camming fashion, so aiding the inherent resilience of the locking ring and assuring that that ring disengages from groove 15.
With regard to relative axial movement, balls 75 are constrained to the space between flange 53 of ring 36 and end ring 63 of the driving ring. However, since the balls are engaged by cam follower surface 52 and since ring 36 is a split ring and is radially distorted by operation of the driving ring, means must be provided to prevent the balls from entering the space between the ends of ring 36. In this embodiment, this is accomplished by securing to the inner surface 61 of ring 37 a filler block 100, FIGS. 5 and 6, of such thickness, radially of the rings, that the filler block will bridge the radial space between surfaces 52 and 61 and project into the gap between the ends of split ring 36. Since the gap between the ends of the split ring is narrower when both rings occupy their first positions (FIG. 1) and wider when ring 36 occupies its second position (FIGS. 7 and 8), the block has a circumferentially narrower upper portion 101 and a circumferentially wider lower portion 102, the block tapering between those two portions and the effective axial space between the two portions being equal to the effective length of the excursion of ring 36 between its first and second positions. Block 100 is rigidly secured to the driving ring, as by screws 103.
The Embodiment of FIG. 10
The embodiment of the invention shown in FIG. 10 illustrates the fact that the invention is applicable to connectors which employ radially distortable annular locking means other than those based on a split locking ring. Here, the locking means 135 comprises a plurality of circularly arranged identical arcuate segment units each comprising an arcuate segment body 138 and an arcuate follower body 138a rigidly interconnected by a radially extending shaft 138b. Upper wellhead body 101 is generally as described with reference to FIGS. 1-9 and includes transverse annular outwardly projecting flange 108. Connector body 121 is again defined by the combination of flange 108 and member 120, but member 120 is modified to include a cylindrical portion 120a which surrounds groove 115 of body 102 when body 101 has been landed on body 102. In this embodiment, both outer wall portion 126 and inner portion 120a are bolted to flange 108, as shown. Portion 120a includes a plurality of radial bores each slidably embracing the connecting shaft 138b of a different one of the segment units. The annular assembly of segments is yieldably biased radially outwardly by a plurality of pairs of helical compression springs 138c, the springs of each pair being disposed each on a different side of the corresponding shaft 138b and engaged in compression between the follower body 138a and portion 120a of member 120. Each segment body 138 includes a frustoconical locking shoulder 139 which tapers downwardly and inwardly at the same angle as does mating shoulder 116 of groove 115.
The first actuating means, comprising spit ring 136 and piston rods 167 of the associated rectilinear power devices, is as described with reference to FIGS. 1, 7 and 8. The second actuating means, comprising driving ring 137 and piston rods 168, remains as described with reference to FIGS. 1, 7 and 8. Antifriction balls 175 are again engaged between cam follower surface 152 of ring 136 and camming surface 161 of the driving ring.
While FIG. 10 illustrates the connector with rings 136 and 137 in their raised initial positions, it will be apparent that, when ring 136 is driven downwardly to its second position (corresponding to that seen in FG. 7 the inner surface portions of ring 136 will coact with the mating outer surface portions of follower bodies 138a to force the segment units radially inwardly until, when ring 136 reaches its lowermost or second position, locking shoulder 139 is in flush engagement with mating shoulder 116. Then, when driving ring 137 is moved downwardly to its second position (corresponding to FIG. 8) the combination of ring 136 and the segment units is forced radially inwardly to cause a strong wedging action between shoulders 139 and 116 to establish the desired large clamping force and compressive preload.
It will be apparent from the foregoing, and from the disclosure in aforementioned copending application Ser. No. 327,445, that the invention is applicable to connectors employing other types of locking means, such, for example, as an annular series of pivoted locking dogs as disclosed in U.S. Pat. No. 3,096,999, or the conventional collet type of locking means.
While the invention has been illustrated and described with reference to connectors in which the locking means is radially distorted between an outer, inactive position and an inner, active position, it will be apparent to those skilled in the art that the invention is also applicable to connectors in which the annular locking means is resiliently distortable from an inner, inactive position to an outer, active position. While the antifriction elements have been shown and described as spherical balls, it will be understood that other rolling antifriction elements can be used, such as rollers in the manner described in aforementioned application Ser. No. 327,445. | Connector, particularly for use in underwater well installations, for securing members together under large clamping forces. The connector is characterized by two successive stages of actuation of a locking means, typically a split ring or set of arcuate segments, with the actuating force of the second stage being applied by camming surfaces via low friction means to establish a high compressive preload without use of especially large power devices. | 8 |
BACKGROUND
High silica zeolitic materials are important catalysts by virtue of high stability and controlled acidity. Numerous methods have been developed to dealuminate aluminosilicate zeolites and convert them into high silica analogs, see, for example, Kerr (Amer. Chem. Soc. Symp. Ser. #121, p. 219 (1973)), McDaniel and Maher (Amer. Chem. Soc. Monograph #171, p. 285 (1976)), and Scherzer (Amer. Chem. Soc. Symp. Ser. #248, p. 157 (1984)). More recently, much interest has focused on dealumination using ammonium silicon hexafluoride, see for example, Breck and Skeels (Proc. 6th. Int'l. Zeolite Conf., p. 87, (1984) Butterworks Press) and nonaqueous solvents with SiCl 4 , [see Rees and Lee (P.C.T. W088/01254 (1988))]. All of these methods suffer from a tendency to non-selective Al 3+ removal, with selective surface enrichment with silicon or aluminum. Furthermore, they are difficult to control at specific Al 3+ removal levels, and in some cases significantly damage the pore structure of the zeolite.
SUMMARY OF THE INVENTION
The methods of the present invention are not limited to aluminosilicate zeolites but are applicable to molecular sieves and zeolites in general together with other molecular sieve types, including phosphates, titanates, stannates, zirconates, and analagous materials such as pillared layered structures.
Applicants' invention provides a method for selective element, particularly silicon, enrichment which avoids the drawbacks of the prior art. Applicants have discovered that if a zeolite is made in the transition metal aluminosilicate form, wherein a certain number of tetrahedral framework (T) atoms are replaced by transition metals (Fe +3 , Cr +3 , Zn +2 , etc.), the transition metal is uniformly distributed throughout the T-sites in the structure. By selectively removing the transition metal to create a vacancy, then annealing the product in the presence of a Si source, a material having a high silica/alumina ratio and a uniform distribution of Al 3+ results. The additional silica is incorporated into the sites previously occupied by the removed transition metal in an ordered manner, affording a material with an even higher silica/alumina ratio. The vacancy can also be filled with other elements not easily substituted into the structure by conventional synthesis methods (e.g., Ti, Zr and Sn). Applicants have discovered that the transition metal can be selectively removed by demetallating a transition metal containing crystalline material with a complexing agent under reaction conditions which do not also remove the Al 3+ or Si 4+ . The method thus provides means to produce highly ordered high silica alumina ratio zeolites, as illustrated in FIG. 1. As used herein, demetallation refers to the removal of transition metal from a transition metal containing crystalline material, creating vacancies, which may then be filled with another element. In some cases the vacancies, often viewed as "hydroxyl nests" (R. M. Barrer, "Hydrothermal Synthesis," Academic Press, Ch. 6), may be left as reactive sites within the structure. The process may be visualized as shown in FIG. 1.
Zeolites and molecular sieves comprise framework structures in which an oxygen framework is crosslinked by tetrahedrally or octahedrally (or mixtures of both) coordinated highly charged cations. Typically those cations may be mixtures of IV Si 4+, IV Al 3+, IV p 5+, (IV Si 4+ + VI Sn 4+), (IV Si 4+ + VI Ti 4+), (IV Si 4+ + VI Zr 4+), and numerous other combinations. Framework charge deficiency, created by various cationic substitutions into these framework cation positions, require the presence of charge balancing cations. These may occupy specific "nonframework" "exchange" sites within the open space of the framework and sometimes be very mobile within this space. These exchangeable cations can be readily replaced or removed by numerous methods known in the art and are not the target of this invention. The "framework" cations however are locked into the oxygen network and are difficult to remove or replace. Numerous methods have been developed to control this "framework" composition in molecular sieve materials, either by direct synthesis or by "secondary synthesis," particularly dealumination methods (as described in the Background section of this disclosure). This invention discloses an improved method for manipulating this "framework" composition by utilizing the selective complexing of transition metals by selected complexing agents. The target material is first synthesized so as to contain transition metals in the framework positions of the structure. These will occupy either specific preferred framework sites or randomly replace the established framework cations. On contact with a complexing agent under controlled pH conditions the transition will be selectively "leached" or reacted from the framework leaving a vacancy. This vacancy can then be filled in a concurrent or post-reaction, or merely left as a "hole" in the structure. Clearly too many residual "holes" lead to the collapse of the framework, but their number may be controlled by the initial synthesis of the transition metal form of the structure and the de-metallation reaction conditions (nature of the complex; temperature; pressure; complex concentration; pH; contact time; etc.) so that this problem can be avoided. The important factor is that only the transition metal is removed and the Al and Si are left in the framework.
The present invention is directed to a method for demetallating crystalline molecular sieve materials comprising the steps of:
(a) synthesizing a crystalline molecular sieve material having framework cation positions wherein a transition metal is contained in said framework cation positions;
(b) removing said transition metal from said framework cation positions of said crystalline molecular sieve material by contacting said transition metal containing crystalline material with a complexing agent for a time and at a temperature sufficient to remove said transition metal from said crystalline molecular sieve material;
(c) thermally or hydrothermally annealing said crystalline molecular sieve material having said transition metal removed therefrom.
The process may further comprise adding a source of silicon, zirconium, aluminum, boron, gallium, germanium, phosphorus, titanium, vanadium, manganese and mixtures thereof to said annealing step (c) to increase the amount of silicon, zirconium, titanium, aluminum, boron, gallium, germanium, vanadium, manganese, phosphorus, and mixtures thereof incorporated into the final demetallated crystalline molecular sieve material.
The materials prepared in accordance with the present invention can be used as catalysts in fluid catalytic cracking, hydrocracking, reforming, and other hydrocarbon conversion processes, or as selective sorbents and ion exchangers. The process is especially useful for the property enhancement (i.e., stability, reactivity) of zeolites subjected to severe environments such as steam and H 2 S and for the preparation of hydrophobic selective sorbents.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates schematically the process of this invention wherein a transition metal M is selectively removed from a framework site by complexation, followed by vacancy (V) filling with another element N.
FIGS. 2a-c are the 29 Si- Magic Angle Spinning Nuclear Magnetic Resonance (MASNMR) spectra for ECR-22D (Ni-LTL), de-nickelated ECR-22D and the realuminated product of Example 17, respectively.
FIG. 3 shows a similar sequence of spectra for ferri-faujasite (Ferr-FAU), the deferrated form, and the resilicated product of Example 19.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a general method which can be applied to a wide range of materials containing transition metals. The transition metals which may be selectively removed by the present method include all transition metals. Such transition metals are those elements of the periodic table having partially filled d or f shells. The method is especially useful for removal of iron, nickel, cobalt, chromium, zinc, vanadium, manganese, copper, gallium, and mixtures thereof. The method is especially applicable to transition metal zeolites or porous molecular sieves with the specific purpose of making highly stable selective catalysts and sorbents. Such materials include metal alumina-phosphates, metal silicoalumino phosphates, metallosilicates, metal-stannosilicates, titanosilicates, zirconosilicates etc. The method selectively removes transition metal without effecting the removal of other majority elements which are usually Si, Al, or P.
The transition metal containing material, for example zeolite, may be prepared by methods known to those skilled in the art. See for example U.S. Pat. No. 4,961,836, co-pending U.S. Ser. No.746,263 (U.S. Pat. No. 5,185,138) and Ser. No. 746,264 (U.S. Pat. No. 5,185,137) and Ser. No. 746,265 (U.S. Pat. No. 5,185,136) (now allowed) herein incorporated by reference. Several ferrisilicate zeolite analogs have been described by Ratnasamy and Kumar (Catalysis Today, V. 9, (4), (1991)). The transition metal containing material is then contacted with a complexing agent having a pH above about 3.0 for a time and at a temperature sufficient to effect the desired amount of transition metal removal. Such an amount of time is easily determined by one skilled in the art. An example of a suitable complexing agent is disodium EDTA. The contacting is carried out at a temperature of about 0° C. to about 300° C., a subsequent annealing step heals the structure. The annealing is accomplished by heating and may be carried out in the presence of a compound whose cation can replace the removed transition metal. Alternatively, the annealing step may be carried out as a solution reaction using aqueous or nonaqueous solvents containing dissolved substitutional metals. For example a silicon, zirconium, aluminum, boron, gallium, germanium, phosphorus, vanadium, manganese, titanium compound and mixtures thereof as substitutional metals can be used. Nonlimiting examples of suitable compounds include silicon tetrachloride, tetramethylorthosilane, tetraethylorthosilane, and titanium isopropoxide, tetramethyltitanate, etc. Annealing migrates the added element (Si, Ti, Zr, Al, B, Ga, Ge, P, V, Mn) into vacancies from which transition metal has been removed thereby stabilizing the structure. Such alternate methods are well known in the art as described in, for example, U.S. Pat. Nos. 4,503,023 and 5,098,687 and PCT WO.88.01254.
When applying the present invention to zeolites, a zeolite in a transition metal alumino silicate form is first prepared or obtained, in which the transition metal is uniformly distributed throughout the T sites in the structure. The transition metal is then removed resulting in a higher silica:alumina ratio material having a uniform vacancy distribution. To selectively remove the transition metal without effecting Al 3+ removal, the transition metal is dealuminated with a complexing agent, having a pH above about 3.0, e.g. disodium EDTA. The complexing agent chosen does not effect Al 3+ removal. The prior art which uses complexing agents use the acid forms of the complexing agents, leading to Al 3+ removal (Kerr, Amer. Chem. Soc. Symp. Ser. 121, p 219, (1973); Pickert and Murphy, U.S. Pat. No. 4,961,836). The resultant material of this invention then annealed with an additional supply of SiO 2 to fill the sites previously occupied by the transition metal, resulting in a zeolite with a high silica/alumina ratio and uniform Al 3+ distribution. Such zeolite materials with increased silica/alumina ratio have increased stability in steam and also improved acid site activity making them highly desirable as catalysts by virtue of their steam regenerability, enhanced thermal stability and controlled acidity.
The following examples are illustrative though not limiting.
EXAMPLE 1
A 125 mL acid digestion bomb (Teflon lined) was charged with 2.0 g of FE-FAU (iron substituted faujasite) and 100 mLs of a 5% solution of Na 2 H 2 EDTA. This bomb was mounted on a rotating shelf in a 200° C. oven for seven hours. The product was filtered, washed and dried in a 115° C. oven. The very light tan product was analyzed by ICP-AES using Li 2 B 2 O 7 /Li 2 CO 3 fusion method to dissolve the sample.
TABLE I______________________________________ Si/ Fe/ % % % % Al + Al + UnitSample Al Si Na Fe Fe Fe Cell (A)______________________________________Fe-FAU 5.61 23.5 6.94 5.45 2.74 0.32 24.646*Fe-FAU 7.03 31.3 5.22 0.26 4.20 0.02 24.608______________________________________
The asterisk indicates that the material has undergone demetallation in accordance with the instant invention.
The above data show that almost all of the Fe 3+ has been removed without removal of any Al 3+ .
EXAMPLE 2
A 125 mL acid digestion bomb (Teflon lined) was charged with 6.0 g of NI-LTL (nickel substituted Linde Type L zeolite), 90 mLs of H 2 O, 10 g Na 2 H 2 EDTA and 2.4 g of 50% NaOH. This bomb was placed in a 150° C. oven for 3 days. The product was filtered, washed and dried in a 115° C. oven. The very light green product was analyzed by ICP-AES using the HF/aqua regia method to dissolve the sample, showing almost complete nickel removal without simultaneous removal of Al 3+ .
TABLE II______________________________________ % % % % Si/Al + Ni/Al +Sample AL Si Na % K Ni Ni Ni______________________________________Ni-LTL 7.02 23.8 0 11.3 4.07 2.57 0.21*Ni-LTL 7.81 26.6 1.08 9.33 0.73 3.14 0.04______________________________________
The asterisk indicates that the material has undergone demetallation in accordance with the instant invention.
EXAMPLE 3
A 125 mL Teflon bottle was charged with 2.0 g of Fe-FAU (deep bed steamed at 550° C./2 hr), 25 mL water and placed in a 90° C. water bath. A total of 0.63 g of H 4 EDTA was added over a period of 6 hours (at a rate of 1/6 every hour). The product was filtered, washed with hot distilled water and dried in a 115° C. oven. This is a conventional treatment favored by other researchers (e.g. Kerr). The light tan product was analyzed by ICP-AES using the HF/aqua regia method to dissolve the sample.
TABLE III______________________________________ % % % % Si/ Fe/Sample AL Si Na Fe (Al + Fe) (Al + Fe)______________________________________Fe-FAU 6.14 22.5 7.74 4.72 2.57 0.27*Fe-FAU 5.77 29.9 6.23 4.37 3.64 0.27______________________________________
The asterisk indicates that the material has undergone nonselective demetallation using conventional techniques.
This example shows that Al 3+ and Fe 3+ have been removed in equal amounts, showing no selectivity for the conventional method using H 4 EDTA.
EXAMPLES 4-16
A series of experiments was performed by charging 2.0 grams of various transition metal substituted zeolites and 80-90 mls of a 5% solution of Na 2 H 2 EDTA to 125 ml acid digestion bombs (Teflon lined). The bombs were mounted on a rotating shelf (14 rpm) in a 200° C. oven for 7-8 hours. The products were filtered, washed with distilled water and dried in a 115° C. oven. The untreated zeolites and their demetallated products were analyzed by ICP-AES to have the following values shown in Table IV.
TABLE IV__________________________________________________________________________ Trans. Si Si Na + K MExampleZeolite Metal % Al % Si % K % Na % M Al Al + M Al + M Al + M__________________________________________________________________________ 4 LTL Fe 6.41 24.8 12.0 5.95 3.72 2.57 0.89 0.31*LTL Fe 7.70 30.4 10.2 1.00 2.66 3.79 3.25 0.91 0.14 5 LTL Ni 5.92 26.0 9.0 11.50 4.22 2.23 0.55 0.47*LTL Ni 7.19 33.1 9.0 0.86 0.31 4.42 4.34 0.98 0.02 6 MAZ Fe 5.30 27.6 0.0 6.77 5.13 5.00 3.41 1.02 0.32*MAZ Fe 5.71 29.7 0.0 4.74 2.28 5.00 4.19 0.82 0.16 7 MAZ Ni 5.89 24.2 0.0 4.70 8.82 3.95 2.34 0.55 0.41*MAZ Ni 7.23 30.3 0.0 4.20 0.09 4.03 4.00 0.68 0.01 8 FAU Fe 5.40 24.7 0.0 7.42 5.91 4.39 2.87 1.05 0.35*FAU Fe 6.91 28.4 0.0 5.18 0.14 3.95 3.91 0.87 0.01 9 LTL Zn 4.42 26.9 14.4 7.31 5.85 3.47 1.33 0.41*LTL Zn 5.78 33.3 7.3 0.71 0.06 5.53 5.51 1.01 0.0010 MAZ Zn 6.36 26.4 0.0 5.48 4.85 3.99 3.03 0.77 0.24*MAZ Zn 6.90 29.4 0.0 4.31 0.11 4.09 4.07 0.73 0.0111 MAZ Fe 3.66 27.8 0.0 5.78 7.01 7.30 3.79 0.96 0.48*MAZ Fe 4.60 34.9 0.0 3.07 2.56 7.29 5.74 0.62 0.2112 ECR-32 Fe 4.44 28.7 0.0 3.13 4.49 6.21 4.17 0.56 0.33*ECR-32 Fe 4.38 31.2 0.0 3.32 0.31 6.84 6.62 0.86 0.0313 GME Cr 6.29 25.2 0.0 7.99 3.79 3.85 2.93 1.14 0.24*GME Cr 7.45 26.7 0.0 6.27 1.06 3.44 3.21 0.92 0.0714 GME Cr 8.90 26.6 0.0 6.84 0.79 2.87 2.74 0.86 0.04*GME Cr 7.80 26.3 0.0 6.28 0.25 3.24 3.19 0.93 0.0215 GME Zn 6.27 23.7 0.0 8.23 4.90 3.63 2.75 1.16 0.24*GME Zn 6.98 27.6 0.0 5.58 0.04 3.80 3.79 0.94 0.0016 LTL Zn 3.61 24.9 12.0 0.00 8.03 6.63 3.45 1.20 0.48*LTL Zn 5.00 32.8 4.8 0.58 0.19 6.30 6.20 0.79 0.02__________________________________________________________________________
The asterisk indicates that the material has undergone demetallation in accordance with the instant invention.
In all cases either essentially all, or most, of the transition metal is removed. After annealing a subsequent treatment the instant invention will remove the small residue of transition metal. The initial removal followed by annealing increases the stability of the framework.
EXAMPLE 17
To demonstrate the ordered filling of lattice vacancies created by de-nickelation of the product of Example 5, a de-nickelated Ni-LTL (designated ECR-22D in co-pending U.S. Ser. No. 746,263), this product was "exchanged" with a solution of sodium aluminate. Thus, the ECR-22D of Example 5, having the 29 Si-MASNMR spectrum shown in FIG. 2a, was de-nickelated according to the method of Example 5, producing an aluminosilicate LTL having the 29 Si-MASNMNR spectrum shown in FIG. 2b. 2 gms of the latter were reacted with 10 cc solution of sodium aluminate containing 0.15 gm Al 2 O 3 , at 60° C. for 2 hours. The product was filtered, washed with distilled water, then calcined for 2 hours at 500° C. The 29 Si-MASNMR spectrum of this re-aluminated material is shown in FIG. 2c. Apart from the sideband complexity caused by Ni in the structure, FIG. 2a has the same center of mass as FIG. 2c, indicating a similar Si/(Al+D) ratio. The center of mass of FIG. 2b is clearly showing a higher Si/(Al+D) ratio, confirming the D (in this case Ni) is first removed from the structure then the vacancies are filled with back exchanged Al.
EXAMPLE 18
Four 125 ml. acid digestion bombs (Teflon lined) were charged with 2.0 g. of Fe-FAU and 80 mls of a 5% solution of Na 2 H 2 EDTA. This bomb was mounted on a rotating shelf in a 200° C. oven for 8 hours. The product was filtered, washed and dried in an 115° C. oven. The very light tan product was analyzed by ICP-AES using Li 2 B 2 O 7 /Li 2 CO 3 fusion method to dissolve the sample, yielding the following results shown in Tables V and VI.
TABLE V______________________________________ Si/ Fe/Sample % Al % Si % Na % Fe Al + Fe Al + FE______________________________________Fe-FAU 5.40 24.7 7.42 5.91 2.87 .35Fe-FAU* 6.74 29.4 5.32 .17 4.14 .012______________________________________
The asterisk indicates that the material has undergone demetallation in accordance with the instant invention.
The 29 Si-MASNMR spectra are shown in FIG. 3 for the ferrisilicate FAU and the demetallated --FAU, showing a clear shift to higher Si/(Al+M) ratios in the later product.
EXAMPLE 19
The demetallated zeolite from Example 18 (2 grams) was calcined at 400° C. for 2 hours and then refluxed for four hours under dry nitrogen with a solution of 2.5 mls SiCl 4 in 125 mls carbon tetrachloride. The product was washed with carbon tetrachloride and dry ethanol, then analyzed by ICP-AES, giving the composition shown in Tables VI and VII. The 29 Si-MASNMR spectra of this product is shown to have a higher Si/Al ratio compared to the starting material (FIG. 3).
EXAMPLE 20
The demetallated zeolite of Example 18 (2 gm) was calcined at 400° C. for 2 hours then refluxed for 4 hours under dry nitrogen with a solution of 2.5 mls of TiCl 4 in 125 ml carbon tetrachloride. The product was washed with carbon tetrachloride and dry ethanol, then analyzed by ICP-AES, giving the titano-aluminosilicate composition shown in Tables VI and VII.
TABLE VI______________________________________% Al % Si % Na % Fe % Ti Si/(Al + Fe)______________________________________Example 19 7.06 33.4 5.07 .19 -- 4.49Example 20 7.25 31.8 5.18 .17 1.02 4.17______________________________________
The increase in Si/Al+Fe level in Example 19 and the uptake of titanium in Example 20 show that these elements fill the vacancy left by the removed transition metal.
TABLE VII______________________________________Ex- Si Fe Unit Cellample Zeolite Treatment Al + M Al + Fe A______________________________________18 Fe-FAU None 2.87 .35 24.64718 Fe-FAU* Deferrated 4.14 .012 24.59519 SiCl.sub.4 4.49 .013 24.59820 TiCl.sub.4 3.90 .011 24.62821 NaSilicate 4.42 .012 24.603______________________________________
EXAMPLE 21
3 gm of the demetallated product of Example 18 were reacted with a solution of 1.3 gm waterglass solution (PQ Corp. N brand sodium silicate) dissolved in 30 gms H 2 O for 24 hours at 100° C. The product was washed with water, dried at 110° C. then analyzed using ICP-AES, having the increased Si/Al ratio given in Table VII. | A method for demetallating crystalline molecular sieve materials by removing a transition metal in the sieve framework with a complexing agent. | 2 |
BACKGROUND OF THE INVENTION
The field of the invention pertains to machines that automatically form packages from flat blanks, fill the packages with a liquid or highly viscous material, seal the package and discharge the sealed packages for visual inspection. In particular, the invention pertains to the formation of packages from laminated and coated cardboard blanks to produce a complete sealed and sufficiently sterile enclosure for food items, the packages incorporating integral tear-off tops.
Examples of the packages to which the machines are intended are disclosed in U.S. Pat. No. 4,717,046 and German invention document DE 3143671 A1 wherein a separable tongue or top may be torn off to provide the dispensing outlet for the package, however, the disclosure below is not limited to the particular packages disclosed in these publications.
As a further example reference is made to the package with a replaceable tear-off top disclosed in applicant's pending U.S. patent application Ser. No. 07/705,354 wherein laminated flat blanks are formed into packages. In this disclosure the tear-off top is configured and sealed in a manner that permits the top to be replaced over the dispensing outlet after it is torn off.
U.S. Pat. No. 3,382,644 illustrates a bag forming and filling machine. In this machine the bags or packages after forming on a separate apparatus are raised on fixtures to insert nozzles of the filling apparatus into the packages and the packages are filled before the packages are again lowered. Belgian invention publication No. 547082 discloses a package forming and filling sequence wherein the packages are formed by folding a blank up around an upper mandrel. The package rests on a second mandrel through a side sealing station and a filling station, the upper mandrel having been withdrawn to permit filling. The open top formed packages are filled from hoppers that travel with the packages. The hoppers have filling tubes depending therefrom which enter the packages during the filling operation.
Belgian invention publication No. 538036 discloses the use of an upper former or mandrel that drives a blank down into a die. As the bottom portion of the blank is driven down into the die and the package sides partially folded up toward the upper former, a lower former or mandrel moves up into the die to meet the package bottom. The two formers then proceed downward through the die to form the package. Below the die the package proceeds between rotating side sealers and the formers retract allowing the side sealed package to be blown into a chute as it drops from the side sealers.
The machine disclosed in U.S. Pat. No. 4,669,253 forms a package similar to the Belgian disclosures, however, this disclosure provides two significant differences. Firstly, the bottom forming surfaces of the upper and lower mandrel are complementary and the edges of these surfaces register with the upper edges of the die cavity to form the package sidewalls by defining pronounced boundaries between the clamped bottom portion of the package blank and the adjacent outer portions of the package blank. To accomplish these pronounced boundaries, the curvature of the upper edges of the die cavity matches the curvature of the edges of the complementary former surfaces. In the forming cycle the formers come together at exactly the top edge of the die cavity with the package blank therebetween before descending through the die cavity.
Secondly, in U.S. Pat. No. 4,669,253 the package blank is driven through the die and into a fixture. The fixture is indexed from station to station for sealing the package sides, filling the package and top sealing the package. The package is raised from the fixture for side sealing and again raised from the fixture for filling the package. The package is pushed through the fixture and supported from the bottom for top sealing and discharge from the machine below the fixture.
U.S. Pat. No. 4,252,052 discloses a similar package forming machine, however, this machine differs in three significant ways. First, this machine lacks a lower former or mandrel. Second, the lower die comprises two opposed downwardly curving plates that are completely open to allow the package edges to remain apart. Third, the package edges are air heated to activate the sealant before the edges are clamped together. The air heater is inserted between the package edges before the edges are clamped together.
The formation of pouch type packages from coated paper board blanks requires careful and accurate folding and sealing. The open package must then be transported for dosing or filling with product and finally positioned for sealing of the filled package. With a view toward avoiding unnecessary movement of the package through the forming, filling and sealing cycle, applicant has developed the machine and method disclosed below.
SUMMARY OF THE INVENTION
The invention comprises a step by step method of forming packages or containers from blanks, heat sealing the sides of the packages and depositing the packages in fixtures, retaining the packages in the fixtures during dosing of the packages with product, heat sealing the tops of the packages and ejecting the packages from the fixtures. The formed packages remain in the fixtures from first placement therein until filled and completely sealed thereby greatly simplifying a complex package forming, filling and sealing procedure on an automatic machine.
In forming the package, a blank is placed on a tray above a forming die and positioned with the center of the blank spaced above the die and below an upper reciprocable mandrel or former. A second mandrel or former ascends to meet the center of the blank above the die and together with the descent of the upper mandrel draw the blank down into the die opening. The mandrels drive the blank center down into the die causing the blank sides to fold upwardly.
With the blank drawn down fully into the die, the mandrels hesitate momentarily as heated elements enter vertical apertures in the sides of the die and heat seal the sides of the blank together to form an open top package.
The mandrels then resume the downward movement through the die to deposit the packages in a fixture. Once deposited in a fixture, the package remains in the fixture and is indexed from station to station until filled and the top sealed.
The filling station bottom fills the open packages by dosing each package with a measured amount of liquid or paste like product. With simultaneous dosing of a plurality of packages in a plurality of fixtures each package is fed by an adjustable stroke bellows pump. Normally all of the bellows pumps will be adjusted for equal dosages, however, the machine is capable of simultaneously filling differing amounts into packages in separate fixtures. A single hopper feeds a manifold in turn directly connected with tubes to the bellows pumps. The bellows pumps in turn are connected with tubes to filling tubes that bottom feed the packages.
Although applicable to almost any liquid product from the thin and watery to very thick viscous pastes, the adjustable dosing apparatus is particularly suited to products that must be packaged essentially contamination free such as food items, creams and lotions, and medicinal items. The dosing apparatus and entire machine is particularly suited for clean room operation.
Of particular advantage, the hopper and manifold merely rest in the machine on brackets from which they can be easily lifted and disassembled for cleaning. The flexible connecting tubes are smooth walled plastic and the filling tubes smooth walled metal tubes that merely rest in a vertically movable carrier. As with the hopper and manifold, the tubes can be disassembled for cleaning and reassembled without tools. The bellows pumps with check valves likewise can be removed from the machine without tools, however, because the bellows and check valves can not so easily be thoroughly cleaned, they are made from inexpensive plastic and are discarded to prevent any contamination with product changes.
Since the dosing apparatus may be used for products sensitive to degradation with time when exposed to the environment, ease of disassembly, cleaning and reassembly is paramount to the reduction of downtime. Product never contacts any complex moving mechanical parts and the dosing apparatus may be cleaned as often as necessary. The machine with this particular dosing apparatus is particularly suitable for contract packages who frequently change from one product run to a different product for the next run. Under such circumstances prevention of contamination by a previous product is paramount.
The open but filled package is indexed to a top sealing or closure station where an ejector or anvil raises the package in the fixture to expose the top for heat sealing. Upon heat sealing the ejector further raises the package from the fixture into an unloading station wherein the package slides down a chute in full view of an operator for inspection purposes prior to discharge from the machine.
The machine is capable of high production rates with short downtimes for cleaning and change of product. The package, upon being formed follows a simpler less complicated path than the nearest previous similar machines and therefore presents fewer mechanical problems with off size blanks and packages.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of the stations for the machine;
FIG. 2 schematically illustrates the movement of flat package blanks from the loading station into the forming station;
FIG. 2a illustrates the shape of a flat package blank;
FIG. 3 is a schematic top view of the lower portion of a pair of package forming units;
FIG. 4 is a schematic side view of the lower portion of a package forming unit;
FIGS. 5a, 5b, 5c and 5d illustrate schematically the package forming sequence at the forming station;
FIG. 6 is a partial perspective view of a fixture and package;
FIG. 7 is a partial perspective view of the fixture arm at an intermediate sensing station;
FIG. 8 is a schematic view of the filling apparatus at the filling station with a filling tube inserted in a package;
FIG. 9 is a schematic view of the filling nozzle retracted above the package;
FIG. 10 is a schematic view of the suck back mechanism taken in the direction 10--10 in FIG. 8;
FIG. 11 is a schematic view of the adjustable pumping mechanism for the filling apparatus;
FIG. 12 is a schematic view of the beginning of the package ejection from the fixture at the final sealing station;
FIG. 13 is a schematic view of the final sealing of the package;
FIG. 14 is a schematic view of the package elevating track; and
FIG. 15 is a schematic view of the package inspection chute.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 as shown the floor plan of the packaging and filling machine is a square 20. Within the plan is a motor driven index drive turntable 22 having twelve arms 24 extending radially therefrom. Each of the twelve arms 24 supports a plurality of package retaining fixtures disclosed below. At each index cycle of the index drive 22 the arms 24 move one-twelfth of a full rotation.
Above the rotating arms 24 and fixtures are located the three principal stations, in particular, the package forming station 26, the filling station 28 and the final sealing station 30. In addition, a loading station 32 for package blanks and an unloading station 34 for the inspection of filled packages adjoin the forming station 26 and the final sealing station 30 respectively. Two separate sensor stations are included at locations separate from those above. The sensor station at 36 senses for formed open packages in each fixture location before the arm 24' rotates into the filling station 28. The sensor station at 38 senses for empty fixtures before the arm 24" rotates into the forming station 26.
In FIG. 2 the loading mechanism and sequence is shown comprising a tilted chute 40 stacked with a quantity of package blanks 42. Within the chute 40 is a weight 44 on rollers 46 that rests against the stack of blanks 42 so that they move down the chute 40 in proper orientation for feeding to the forming station 26. The forwardmost blank 48 is retained at the end of the chute by small tabs or edges on the end of the chute 40 such that blank 48 can be grasped by suction cups 50 on the grabber 52.
The grabber 52 moves over and up as indicated by arrow 54, grasps the blank 48 with the suction cups 50 and then retracts back, down and horizontally to the right as indicated by arrow 56. FIG. 2a shows the shape of the blanks 48 with tabs 58 at each end that eventually form the dispensing outlet and tear-off top of the package. The central portion of the blank 48 as indicated at 60 eventually forms the bottom of the package.
Returning to FIG. 2 the grabber 52 includes an embossing or imprinting wheel 62 which with air cylinder and piston rod 64 causes a serial number or identification number to be added to the central portion 60 of the blank 48. With the blank in this position a rotator 66 having a gripper 68 grips the blank 48 and retains the blank in a vertical position as the grabber 52 retracts to the left and upwardly. The gripper 68 is rotatable into gripping position as indicated by the arrow 70 and grasps the lower one of the tabs 58 on the blank 48.
With the grabber 52 cleared, the rotator 66 moves with the blank 48 as indicated by arrow 72 to place the blank 48 horizontally above the forming tray 74 in the forming station 26. The blank 48 is then lowered onto the tray 74, the gripper 68 disengaged from the blank 48 and the rotator 66 retracted to its former position. Pins 76 are located on the tray 74 to either side of the tab 58 that had been in the gripper 68. At the other end of the blank 48 a pair of wires 78 rotatable as indicated by arrow 80 engage the blank 48 to either side of tab 58 and push the blank 48 into engagement with the pins 76 thereby properly placing the blank 48 in the tray 74 for the package forming operation.
In FIGS. 3, 4, 5 and 6 the package forming and fixture loading process occurs at station 26. In FIGS. 3 and 4 two parallel trays 74 are illustrated with the pins 76 and wires 78. The tray 74 is generally open at 82 to provide clearance for the gripper 68 as the blank 48 is placed on the tray. And, the tray 74 bottom is fully open transversely at the center 84 to provide an aperture leading to the forming die 86 therebelow. The die cavity 88 is generally oblong with slots 90 to each side. At the top the die 86 is generally curved in a smooth manner to guide the blank 48 into the die. Beneath each tray 74 and upper portion of the die 86 are dual opposed heated sealers 94 that are actuated by air cylinders 96 to seal the edges of the package. The sealers 94 enter and retract through slots 98 in the die 86 as shown in FIG. 5 to squeeze the edges of the package together and seal them.
In FIG. 5 the sequence of forming the package and placing the package in a fixture is shown. In FIG. 5a the blank 48 is lying in the tray 74 spaced above the die cavity 88. The lower mandrel 100 is ascending and the upper mandrel 102 is descending. With the lower mandrel 100 at the top of its stroke partially above the top of the die cavity and just below the blank 48 on the tray 74, the upper mandrel 102 forces the center 60 of the blank 48 down against the top 104 of the lower mandrel 100. The bottom 60 of the package is formed by the complementary bottom 105 of the upper mandrel 102 against the top 104 of the lower mandrel. With the bottom 60 of the package trapped between the mandrels 100 and 102, the mandrels descend into the die cavity 88 drawing the blank 48 with them as shown in FIG. 5b. The sides 106 of the package are driven upwardly against the upper mandrel 102 by the action of the mandrels 100 and 102 in driving the bottom 60 of the package down into the die cavity 88 in conjunction with the smoothly curved upper edges 108 of the die cavity 88. The sides of the lower mandrel 102 are partially flattened at 103. The two mandrels 100 and 102 may suitably be actuated by air cylinders (not shown).
The two mandrels 100 and 102 carry the package blank 48 down fully into the die cavity 88 to the hesitation position shown in FIG. 5c. The edges of the package are thereby aligned with the slots 98 whereupon the heat sealers 94 are actuated to enter the slots 98 and heat seal the package edges together. The heat sealers 94 are mounted on springs 110 to self align and thereby provide a more even seal on the package edges.
Upon retraction of the heat sealers 94 the downward motion of the mandrels 100 and 102 resumes until the package, now denoted 61, is deposited in the fixture 112 atop an arm 24 as shown in FIG. 5d. The lower mandrel 100 further descends as shown to clear the arm 24. With the package 61 deposited in the fixture 112, the upper mandrel 102 ascends to clear the arm 24, package 61 and fixture 112 and further to clear the tray 74 and rotating motion of the blank 48 shown in FIG. 2.
It is important to note that the package 61 once deposited as shown in FIG. 5d and FIG. 6 remains in the fixture 112 through the filling station 28 and into the sealing station 30. It is also important to note that while described above generally in terms of one package forming unit and loading unit, in most embodiments a plurality of units at each station are employed so that several identical operations are produced in parallel at each station. In the prototype machine seven fixtures 112 are mounted in-line on each arm 24. At each station including the load 32 and unload 34 stations seven operations proceed in parallel.
In FIG. 7 intermediate sensing station 36 comprises a plurality of sensors 114 that each check for a package 61 in the fixture 112 thereabove. In the event that a package is absent, the subsequent filling unit at station 28 for that particular fixture is temporarily disabled to prevent spillage, however, the machine continues to operate. A similar plurality of sensors 114 are located at sensor station 38, however, the fixtures are normally empty at this portion of the cycle. In the event that a package was not discharged at the final sealing station 30, a sensor 114 at station 38 stops the machine until an operator can empty the fixture.
Turning to the filling station 28 illustrated in FIG. 8 is a hopper 116 for the supply of filling product or material to be supplied to the individual packages 61 therebelow. The hopper 116 is connected with a circumferential quick disconnect clamp 118 to a manifold 120 having a plurality of orifice tubes 122. The orifice tubes 122 in turn are each connected through plastic tubes 124 to bellows pumps 126. The outlets of the bellows pumps 126 communicate through plastic tubes 128 with filling tubes 130. As shown the filling tubes 130 are fully lowered into the packages 61 through the open tops 132. Only one pumping and filling circuit is shown although as indicated by the number of orifice tubes 122 shown on the manifold 120 seven are intended and seven packages 61 are filled simultaneously.
A squeezing stroke of the bellows pumps 126 causes a measured dose of product to be expelled from the filling tubes 130 into the packages 61 as the filling tubes 130 are raised upwardly. Thus, product is bottom fed to the packages 61. To accomplish the filling stroke, the filling tubes 130 are retained in vertically movable frame member 134 and the lower portions of the tubes 128 grasped in the vertically movable frame 136. Thus, in FIG. 8 a filling tube 130 is shown in its lowermost position and in FIG. 9 in its uppermost position.
As shown in FIGS. 8 and 9 the packages 61 are vertically positioned in the fixtures 112 on the arms 24. In their uppermost position the filling tubes 130 clear the package tops 132 to permit the fixtures 112 on the arm 24 to index out and the next arm 24 with the next set of fixtures 112 and empty packages 61 to index in beneath the filling tubes 130.
Intermediate the lowermost position and the uppermost position on the upward filling stroke, the bellows pump 126 completes the product expulsion stroke. To control or eliminate drip or creep of excess product from the tips of the filling tubes 130, the plastic tubes 128 are grasped between frame members 138 and 140 as best shown in FIG. 10. Frame member 140 is movable relative to frame member 138 to squeeze shut plastic tubes 128 upon completion of the product expulsion stroke by the bellows pumps 126. A plurality air cylinders 142 are employed to provide even squeezing of all tubes 128 by member 140 thus terminating flow of product. The air cylinders 142 react against frame members 144 and the entire assembly raises and lowers with the filling tubes 130.
With the beginning of the expansion stroke of the bellows pumps 126, the outlet valves within the bellows pumps close sealing the upper ends of the tubes 128. With the tubes 128 thus sealed the air cylinders 142 open the frame members 138 and 140 causing a slight momentary suction or "suck back" in the filling tubes 130 and thereby controlling or preventing drip or creep of product from the tips of the filling tubes 130. Suction is maintained merely by the viscosity and surface tension of the product until the filling tubes 130 are again lowered into empty packages to repeat the filling cycle.
In FIG. 11 the mechanism for actuating a bellows pump 126 comprises an adjustable stroke air cylinder 146 wherein the piston rod 148 engages a lever arm tip 150 and arm 152. The arm 152 rotates about a fulcrum 154 with a pump rod 156 attached at the end opposite the air cylinder 146. Affixed to the upper end of the pump rod 156 is an internally threaded cap 158. The bellows pump 126 base is threaded into the cap 158. Inlet tube 124 and outlet tube 128 are connected to the bellows pump 126 through internal inlet poppet valve 160 and internal outlet poppet valve 162. Thus, the adjustable stroke of the air cylinder piston rod 148 adjusts the stroke of the bellows pump 126 and the quantity of product dispensed. An extension 164 affixed to the lever arm tip 150 reciprocates between a pair of proximity sensors 166 and 168 to sense the operation of the bellows pump 126. These sensors 166 and 168 indicate if no dose of product has been fed to a package. The mechanism illustrated in FIG. 11 is repeated for each of the bellows pumps 126 at filling station 28.
The filling station 28 apparatus is particularly suited to ease of disassembly, cleaning and reassembly of all parts contacted by product. The hopper 116, manifold 120 and clamp 118 are constructed of stainless steel. The tubes 124 and 128 are constructed of a flexible food grade plastic such as polyethylene and internally smooth. The filler tubes 130 are straight smooth walled stainless steel with no internal changes in cross-section. Collars 170 are affixed to the filler tubes 130 to retain the tubes 130 in holes in frame member 134. The plastic tube 124 and 128 connections are sized for frictional engagement with the manifold orifice tubes 122 and the filling tubes 130 as well as with the bellows pump 126 inlet and outlet. The hopper 116 and manifold 120 rest in brackets 172.
Thus, for change of product cleaning the plastic tubes 124 and 128 are slipped off, the hopper 116 and manifold 120 are lifted out of the brackets 172 and disconnected at clamp 118. The bellows pump 126 is unscrewed from the cap 158 and the filling tubes 130 are lifted from the holes in the frame member 134.
The bellows pump 126 and valves 160 and 162, having product contacting areas difficult to clean, are constructed of inexpensive plastics and discarded. The plastic tubes 124 and 128 may be cleaned or discarded as desired and the remaining stainless steel hopper 116, manifold 120 and filling tubes 130 cleaned. No complicated drive, adjusting or sensing devices contact product, therefore they need not be disassembled, cleaned or discarded. Turn-around time for changes in product are greatly decreased in comparison with prior art machines wherein disassembly, cleaning and reassembly require many hours of machine downtime.
As shown in FIG. 12 in final sealing station 30 each package 61 in a fixture 112 located on an arm 24 is contacted from the bottom by an ascending ejector 174. The ejector 174 moves the package 61 upwardly partially out of the fixture 112 and then hesitates in the position shown in FIG. 13. A pair of heated package sealers 176 clamp the top 178 of the package 61 together to complete the sealed package. As shown the package sealers 176 include shaped squeezing dies 180 to provide a tight bond about the top 178 of the package including sealing the tabs 58 together. Each pair of heated package sealers 176 is driven by a pair of air cylinders (not shown) in the same manner as the heated sealers 94 at station 26.
With the completion of the top sealing the ejector 174 continues its ascent fully ejecting the sealed package 61 from the fixtures 112. The package 61 is pushed up into a vertical track 182 in the unloading station 34 as shown in FIG. 14. The package 61 continues up the track 182 into the rotatable tracks 184 as shown. As the ejector 174 begins its descent, the rotatable tracks tilt as indicated by arrow 186 in FIG. 15 and with a nudge from an air nozzle 188 the package 61 begins its descent as indicated at 190. The package 61 slides down a chute 192 and queues against a rotatable stop 194 for easy visual inspection before release into a carton 196. In the prototype embodiment of this machine the seven chutes can be easily watched by the machine operator and packages visually checked.
The arm 24 indexes with empty fixtures 112 into station 38 wherein sensors similar to those at station 36 check for packages not ejected at station 30. In the event a package has not been ejected the indexing of the packaging machine is halted to provide access for the operator to remove the package and restart the machine. | A machine for and a step by step method of forming packages or containers from blanks, heat sealing the sides of the packages and depositing the packages in fixtures, retaining the packages in fixtures during dosing of the packages with product, heat sealing the tops of the packages and ejecting the packages from the fixtures. The sides of a newly formed package are heat sealed through apertures in the forming die before the package is placed in the fixture. Once placed in the fixture at the forming station, the package remains in the fixture during the filling or dosing of product at the filling station and as indexed into the top sealing station. At the top sealing station the filled package is partially elevated from the fixture to expose the entire top of the package for heat sealing. | 1 |
FIELD OF THE INVENTION
The invention relates to the field of solvents. The invention relates more particularly to a composition based on 1,1,1,3,3-pentafluorobutane (HFC-365 mfc). The present invention also relates to a process for dissolving oil.
BACKGROUND OF THE INVENTION
The power of a solvent is generally characterized by the kauri-butanol number, which is the volume in ml at 25° C. of a solvent required to produce a defined degree of turbidity when 20 g of a standard solution of kauri resin are added to n-butanol. This number is equal to 57 for 1,1-dichloro-1-fluoroethane (also known as HCFC-141b).
Besides its good solvent power, HCFC-141b is also characterized by a low surface tension (equal to 19.3 mN/m), which gives it a very good capacity for wetting surfaces. Since the boiling point of HCFC-141b is equal to 32° C., this allows it to evaporate quickly and thus to facilitate the deposition of dissolved products onto substrates. Finally, HCFC-141b has no closed-cup flash point and is therefore a non-flammable solvent.
HCFC-141b thus has properties that give it a good capacity for dissolving many organic compounds, especially silicone oils.
However, on account of its non-negligible action on the ozone layer (ozone degradation potential ODP=0.11), HCFC-141b is subject to major regulations that increasingly target its abolition. Thus, the European regulation on substances that are harmful to the ozone layer (No. 2037/2000) has banned the use of HCFCs (hydrochlorofluorocarbons) such as HCFC-141b in solvent applications since 1 Jan. 2002, except for the fields of aeronautics and aerospace, where the ban will take effect in Europe from 2009.
Document EP 974642 proposes an azeotropic composition of 1,1,1,3,3-pentafluorobutane (known under the name HFC-365 mfc) and of 1,1,1,2,3,4,4,5,5,5-decafluoropentane (known under the name HFC-4310 mee) as replacements for HCFC-141b on account of their absence of effect on the ozone layer. However, the kauri-butanol number of such a composition is much lower than that of HCFC-141b. The kauri-butanol number for HFC-365 mfc is 12, and is equal to 9 for HFC-4310 mee.
A composition comprising from 30% to 70% by weight of 1,1,1,3,3-pentafluorobutane and from 70% to 30% by weight of methylene chloride is moreover known (FR 2 694 942).
Moreover, in the context of environmental protection, the current tendency is towards reducing the emissions of solvent by evaporation. Thus, in many “emissive” applications, i.e. applications for which the solvent is liable to evaporate into the air, solvents that are effective at a temperature lower than room temperature are sought.
The present invention thus provides a composition comprising 1,1,1,3,3-pentafluorobutane, methylene chloride and at least one alcohol containing from 2 to 4 carbon atoms.
DETAILED DESCRIPTION OF THE INVENTION
Ethanol, propanol, isopropanol, butanol, secondary butanol (sec-butanol) or tert-butanol may be suitable. Isopropanol or secondary butanol is preferably used.
The total amount of alcohol present in the composition according to the invention is preferably between 1% and 10% by weight.
The present invention most particularly provides:
1) a composition comprising from 27% to 69% by weight of HFC-365 mfc, from 69% to 27% by weight of methylene chloride and from 1% to 10% by weight of alcohol, preferably from 1% to 5% by weight of alcohol; 2) a composition comprising from 47.5% to 60% by weight of HFC-365 mfc, from 35% to 47.5% by weight of methylene chloride and from 1% to 5% by weight of alcohol.
The compositions according to the present invention may be prepared by mixing together the various constituents. They are advantageously prepared by adding at least one alcohol containing from 2 to 4 carbon atoms to an azeotropic or virtually azeotropic composition of HFC-365 mfc and of methylene chloride.
The compositions according to the present invention have good solvent power and good surface wettability and, furthermore, are non-flammable.
The compositions according to the present invention may be used in industry for cleaning, degreasing and drying a wide variety of solid surfaces (metal components, glasses, plastics and composites). They may also be used in the manufacture of printed circuits to remove the residues of the substances used to improve the quality of the welds. This removal operation is referred to in the art as “defluxing”.
The compositions according to the present invention may advantageously be used to deposit medical-grade silicone oils onto instruments, for example onto syringe needles or catheter needles. In addition, they may be used to deposit silicone oils onto kitchen utensils.
These compositions may also be used as agents for depositing silicone-based greases or polymers or in formulations for cleaning components coated with silicone oils or greases.
The compositions according to the present invention may also be used for dissolving silicone oils included in the formulation of antiadhesive agents (which are often in the form of aerosols) for moulds in processes for manufacturing plastic components (extrusion).
The compositions may also be used as polyurethane foam expanders, as aerosols propellants, as heat-exchange fluids, as textile dry-cleaning agents or as agents for cleaning refrigeration plants.
A subject of the present invention is also a process for dissolving oil. This process is characterized in that a composition comprising 1,1,1,3,3-pentafluorobutane, methylene chloride and at least one alcohol containing from 2 to 4 carbon atoms is used.
The process according to the present invention is preferably performed at a temperature below 10° C. A temperature of between 0 and 8° C. is also preferred. A temperature of between 3 and 6° C. is advantageously chosen.
This process is most particularly suitable for dissolving silicone oil.
The composition according to point 1) is most particularly suitable for performing the process. The composition according to point 2) is preferred.
This process is of major interest, especially in the medical field, when isopropanol or sec-butanol is present in the composition used.
EXPERIMENTAL SECTION
The following compositions were prepared:
Composition A: Azeotropic of 57% by weight of HFC 365 mfc and 43% by weight of methylene chloride
Composition B: 95% by weight of Composition A and 5% by weight of sec-butanol
Composition C: 95% by weight of Composition A and 5% by weight of isopropanol.
EXAMPLE 1
Description of the Silicone Oil Dissolution Tests
A silicone oil Crompton L9000-1000 from the company Crompton Corporation (Greenwich, USA) is used. This is a transparent liquid hydroxypolydimethylsiloxane with a density of 0.97 at room temperature (22° C.), a boiling point of greater than 200° C. and a flash point of 132° C. (Pensky-Martens method, in a closed cup).
Mixtures are prepared at room temperature, i.e. at 22° C.
Thus, 18 ml of the test composition and 1.94 g of silicone oil are introduced into a 50 ml flask, i.e. a 10 vol % solution is prepared. The mixture is then stirred manually for five minutes.
A portion of the mixture thus prepared is kept at rest at room temperature (22° C.) for 24 hours. Another portion is kept at rest at low temperature (6° C.) for seven days.
After the period of storage at different temperatures, the appearance of the mixture is observed precisely. It is considered that there is solubility at room temperature or at 6° C. when the mixture is transparent, clear, homogeneous, monophasic and stable.
Results
Composition
Solubility at 22° C.
Solubility at 6° C.
HCFC-141b
YES
YES
Composition A
YES
NO
Composition B
YES
YES
Composition C
YES
YES
EXAMPLE 2
Description of the Flammability Test
To evaluate the flammability of the compositions, we determined their flash point according to the standardized method ASTM D 3828, Setaflash closed cup. The flash point is the minimum temperature at which a liquid releases vapours in an amount sufficient to form at the surface a mixture that is flammable in air under the action of a source of ignition, but without persistence of flames when the activation energy is withdrawn.
For each of the compositions, the measurement was repeated five times.
Results
Composition
FLASH POINT
HCFC 141b
NO
Composition A
NO
Composition B
NO
Composition C
NO | The invention relates to the field of solvents. The invention relates more particularly to a composition based on 1,1,1,3,3-pentafluorobutane (HFC-365 mfc). The present invention also relates to a process for dissolving oil. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is based upon Provisional Application Nos. 60/007,172, filed Nov. 1, 1995, and 60/009,012, filed on Dec. 21, 1995, priority of which is claimed hereunder.
BACKGROUND OF THE INVENTION
This application is directed to inhibitors of nitric oxide synthase, and in particular cyclic amidines.
Nitric Oxide in Biology
The emergence of nitric oxide (NO), a reactive, inorganic radical gas as a molecule contributing to important physiological and pathological processes is one of the major biological revelations of recent times. This molecule is produced under a variety of physiological and pathological conditions by cells mediating vital biological functions. Examples include endothelial cells lining the blood vessels; nitric oxide derived from these cells relaxes smooth muscle and regulates blood pressure and has significant effects on the function of circulating blood cells such as platelets and neutrophils as well as on smooth muscle, both of the blood vessels and also of other organs such as the airways. In the brain and elsewhere nitric oxide serves as a neurotransmitter in non-adrenergic non-cholinergic neurons. In these instances nitric oxide appears to be produced in small amounts on an intermittent basis in response to various endogenous molecular signals. In the immune system nitric oxide can be synthesized in much larger amounts on a protracted basis. Its production is induced by exogenous or endogenous inflammatory stimuli, notably endotoxin and cytokines elaborated by cells of the host defense system in response to infectious and inflammatory stimuli. This induced production results in prolonged nitric oxide release which contributes both to host defense processes such as the killing of bacteria and viruses as well as pathology associated with acute and chronic inflammation in a wide variety of diseases. The discovery that nitric oxide production is mediated by a unique series of three closely related enzymes, named nitric oxide synthases, which utilize the amino acid arginine and molecular oxygen as co-substrates has provided an understanding of the biochemistry of this molecule and provides distinct pharmacological targets for the inhibition of the synthesis of this mediator, which should provide significant beneficial effects in a wide variety of diseases.
Nitric Oxide Synthases
Nitric oxide and L-citrulline are formed from L-arginine via the dioxygenase activity of specific nitric oxide synthases (NOSs) in mammalian cells. In this reaction, L-arginine, O 2 and NADPH are cosubstrates while FMN, FAD and tetrahydrobiopterin are cofactors. NOSs fall into two distinct classes, constitutive NOS (cNOS) and inducible NOS (iNOS). Two constitutive NOSs have been identified. They are:
(i) a constitutive, Ca ++ /calmodulin dependent enzyme, located in the endothelium and elsewhere (ecNOS or NOS 3), that releases NO in response to receptor or physical stimulation,
(ii) a constitutive, Ca ++ /calmodulin dependent enzyme, located in the brain (ncNOS or NOS 1) and elsewhere, that releases NO in response to receptor or physical stimulation,
The third isoform identified is inducible NOS (iNOS or NOS 2):
(iii) a Ca ++ independent enzyme which is induced after activation of vascular smooth muscle, macrophages, endothelial cells, and a large number of other cells by endotoxin and cytokines. Once expressed, this inducible NO synthase produces NO in relatively large amounts for long periods of time.
Spectral studies of both the mouse macrophage iNOS and rat brain ncNOS have shown that these enzymes (which have been classified as P-450-like enzymes from their CO-difference spectra) contain a heme moiety. The structural similarity between NOS and the P-450/flavoprotein complex suggests that the NOS reaction mechanism may be similar to P-450 hydroxylation and/or peroxidation. This indicates that NOS belongs to a class of flavohemeproteins which contain both heme and flavin binding regions within a single protein in contrast to the multiprotein NADPH oxidase or Cytochrome P-450/NADPH Cyt c reductase complexes.
Distinct Functions of NO Produced by Different Nitric Oxide Synthases.
The NO released by the constitutive enzymes (NOS 1 and NOS 3) acts as an autocoid mediating a number of physiological responses. Two distinct cDNAs accounting for the activity of NOS 1 and NOS 3 in man have been cloned, one for NOS 1 (Nakane et. al., FEBS Letters, 316, 175-182, 1993) which is present in the brain and a number of peripheral tissues, the other for an enzyme present in endothelium (NOS 3) (Marsden et. al., FEBS Letters, 307, 287-293, 1992). This latter enzyme is critical for production of NO to maintain vasorelaxation. A second class of enzyme, iNOS or NOS 2, has been cloned from human liver (Geller et. al., PNAS, 90, 3491-5, 1993), and identified in more than a dozen other cells and tissues, including smooth muscle cells, chondrocytes, the kidney and airways. As with its counterpart from the murine macrophage, this enzyme is induced upon exposure to cytokines such as gamma interferon (IFN-γ), interleukin-1β (IL-1β), tumor necrosis factor (TNF-α) and LPS (lipopolysaccharide). Once induced, iNOS expression continues over a prolonged period of time. The enzyme does not require exogenous calmodulin for activity.
Endothelium derived relaxation factor (EDRF) has been shown to be produced by NOS 3 (Moncada et. al., Pharmacol. Reviews, 43, 109-142, 1991). Studies with substrate analog inhibitors of NOS have shown a role for NO in regulating blood pressure in animals and blood flow in man, a function attributed to NOS 3. A transgenic mouse deficient in functional NOS 3 was shown to be hypertensive, thus validating the role of NO synthesis by NOS 3 in the regulation of blood pressure (Huang et al., Nature, 377, 239-242, 1995). NO has also been shown to be an effector of the cytotoxic effects of activated macrophages (Nathan, FASEB J., 6, 3051-64, 1992) for fighting tumour cells and invading microorganisms (Wright et al., Card. Res., 26, 48-57, 1992 and Moncada et al., Pharmacological Review, 43, 109-142, 1991). It also appears that the adverse effects of excess NO production, in particular pathological vasodilation and tissue damage, may result largely from the effects of NO synthesized by the NOS 2.
NO generated by NOS 2 has been implicated in the pathogenesis of inflammatory diseases. In experimental animals hypotension induced by LPS or TNF-α can be reversed by NOS inhibitors and reinitiated by L-arginine (Kilbourn et. al., PNAS, 87, 3629-32, 1990). Conditions which lead to cytokine-induced hypotension include septic shock, hemodialysis (Beasley and Brenner, Kidney Int., 42, Suppl., 38, S96-S100, 1992) and IL-2 therapy in cancer patients (Hibbs et. al., J. Clin. Invest., 89, 867-77, 1992). NOS 2 is implicated in these responses, and thus the possibility exists that a NOS inhibitor would be effective in ameliorating cytokine-induced hypotension. Recent studies in animal models have suggested a role for NO in the pathogenesis of inflammation and pain and NOS inhibitors have been shown to have beneficial effects on some aspects of the inflammation and tissue changes seen in models of inflammatory bowel disease, (Miller et. al., J. Pharmacol. Exp. Ther., 264, 11-16, 1990) and cerebral ischemia and arthritis (Ialenti et. al., Br. J. Pharmacol., 110, 701-6, 1993; Stevanovic-Racic et al., Arth. & Rheum., 37, 1062-9, 1994). Moreover transgenic mice deficient in NOS 1 show diminished cerebral ischemia (Huang et. al., Science, 265, 1883-5, 1994) and transgenic mice deficient in NOS 2 exhibit enhanced survivability in a model of LPS-induced shock (MacMicking et al. Cell 81, 641-650, 1995) and Wei et al. Nature 375, 408-411, 1995)).
Further conditions where there is an advantage in inhibiting NO production from L-arginine include therapy with cytokines such as TNF, IL-1 and IL-2 or therapy with cytokine-inducing agents, for example 5,6-dimethylxanthenone acetic acid, and as an adjuvant to short term immunosuppression in transplant therapy. In addition, compounds which inhibit NO synthesis may be of use in reducing the NO concentration in patients suffering from inflammatory conditions in which an excess of NO contributes to the pathophysiology of the condition, for example adult respiratory distress syndrome (ARDS) and myocarditis.
There is also evidence that an NO synthase enzyme may be involved in the degeneration of cartilage which takes place in autoimmune and/or inflammatory conditions such as arthritis, rheumatoid arthritis, chronic bowel disease and systemic lupus erythematosis (SLE). It is also thought that an NO synthase enzyme may be involved in insulin-dependent diabetes mellitus. Therefore, a yet further aspect of the present invention provides cyclic amidine derivatives or salts thereof in the manufacture of a medicament for use in cytokine or cytokine-inducing therapy, as an adjuvant to short term immunosuppression in transplant therapy, for the treatment of patients suffering from inflammatory conditions in which an excess of NO contributes to the pathophysiology of the condition.
SUMMARY OF THE INVENTION
The invention disclosed herein encompasses compounds of Formula I ##STR1## and pharmaceutically acceptable salts thereof which have been found useful in the treatment of nitric oxide synthase mediated diseases and disorders, including neurodegenerative disorders, disorders of gastrointestinal motility and inflammation. These diseases and disorders include hypotension, septic shock, toxic shock syndrome, hemodialysis, IL-2 therapy such as in in cancer patients, cachexia, immunosuppression such as in transplant therapy, autoimmune and/or inflammatory indications including sunburn, eczema or psoriasis and respiratory conditions such as bronchitis, asthma, oxidant-induced lung injury and acute respiratory distress (ARDS), glomerulonephritis, restenosis, inflammatory sequelae of viral infections, myocarditis, heart failure, atherosclerosis, osteoarthritis, rheumatoid arthritis, septic arthritis, chronic or inflammatory bowel disease, ulcerative colitis, Crohn's disease, systemic lupus erythematosis (SLE), ocular conditions such as ocular hypertension, retinitis and uveitis, type 1 diabetes, insulin-dependent diabetes mellitus and cystic fibrosis. Compounds of Formula I are also useful in the treatment of hypoxia, hyperbaric oxygen convulsions and toxicity, dementia, Alzheimer's disease, Sydenham's chorea, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis (ALS), multiple sclerosis, epilepsy, Korsakoff s disease, imbecility related to cerebral vessel disorder, NO mediated cerebral trauma and related sequelae, ischemic brain edema (stroke), sleeping disorders, eating disorders such as anorexia, schizophrenia, depression, pre-menstrual syndrome (PMS), urinary incontinence, anxiety, drug and alcohol addiction, pain, migraine, emesis, tumor growth, immune complex disease, as immunosuppressive agents, acute allograft rejection, infections caused by invasive microorganisms which produce NO and for preventing or reversing tolerance to opiates and diazepines.
DETAILED DESCRIPTION OF THE INVENTION
The invention disclosed herein encompasses compounds of Formula I ##STR2## or a pharmaceutically acceptable salt thereof wherein: side a or side b has a double bond,
X is selected from O, S(O) m , NH, and NR 6 ,
wherein R 6 is selected from C 1-12 alkyl, C 1-12 alkyl-carbonyl, C 1-12 alkyloxy-carbonyl, C 1-12 alkylamino-carbonyl C 1-12 alkyl-sulfonyl and C 1-12 alkylamino-sulfonyl wherein said C 1-12 alkyl group being optionally mono or di- substituted by substituents being independently selected phenyl, C 1-6 alkoxy, amino, and halo;
m is 0, 1 or 2;
R 1 , R 2 , R 3 and R 4 are each independently selected from the group consisting of
(a) hydrogen,
(b) C 1-12 alkoxy,
(c) C 1-12 alkyl-S(O) k wherein k is 0, 1 or 2,
(d) mono C 1-12 alkylamino,
(e) (di-C 1-12 alkyl)amino,
(f) C 1-12 alkylcarbonyl,
(g) C 1-12 alkyl,
(h) C 2-12 alkenyl,
(i) C 2-12 alkynyl,
(j) C 5-10 cycloalkyl,
(k) hetero C 5-10 cycloalkyl,wherein the hetero C 5-10 cycloalkyl optionally contains 1 or 2 heteroatoms selected from S, O and N,
(l) aryl, selected from phenyl or naphthyl,
(m) heteroaryl, wherein heteroaryl is selected from the group consisting of:
(1) benzimidazolyl,
(2) benzofuranyl,
(3) benzooxazolyl,
(4) furanyl,
(5) imidazolyl,
(6) indolyl,
(7) isooxazolyl,
(8) isothiazolyl,
(9) oxadiazolyl,
(10) oxazolyl,
(11) pyrazinyl,
(12) pyrazolyl,
(13) pyridyl,
(14) pyrimidyl,
(15) pyrrolyl,
(17) isoquinolyl,
(18) tetrazolyl,
(19) thiadiazolyl,
(20) thiazolyl,
(21) thienyl, and
(22) triazolyl,
(n) C 1-12 alkyl-C(O)NH,
(o) C 1-12 alkoxy-C(O)NH,
(p) C 1-12 alkylamino-C(O)NH,
(q) C 1-12 alkyl-S(O) 2 NH,
(r) C 1-12 alkylamino-C(O),
(s) C 1-12 alkylamino-S(O) 2 ,
(t) aryl-C(O)NH where aryl is selected from phenyl, naphthyl, pyridyl, thienyl, thiazolyl, oxazolyl, imidazolyl, and triazolyl,
(u) aryloxy-C(O)NH where aryl is selected from phenyl, naphthyl, and pyridyl,
(v) phenylamino-C(O)NH,
(w) aryl-S(O) 2 NH where aryl is selected from phenyl and naphthyl,
(x) aryl-C(O) where aryl is selected from phenyl, naphthyl, pyridyl, thienyl, thiazolyl, oxazolyl, imidazolyl, and triazolyl,
(y) phenylamino-S(O) 2 ,
(z) hydroxy,
(aa) amino,
(ab) oxo,
(ac) C(O)OR 7 , R 7 is selected from hydrogen, phenyl, benzyl, cyclohexyl or C 1-6 alkyl,
each of (b) to (y) being optionally mono or di- substituted, the substituents being independently selected from
(1) hydroxy,
(2) --C(O)OH,
(3) --NR 7 R 8 , where R 8 is selected from hydrogen, phenyl, benzyl, cyclohexyl or C 1-6 alkyl,
(4) --NR 7 C(O)R 8 ,
(6) --NR 7 C(O)NHR 8 ,
(5) --NR 7 C(O)OR 9 , where R 9 is selected from phenyl, benzyl, cyclohexyl or C 1-6 alkyl,
(7) --NR 7 S(O) 2 R 9 ,
(8) --OR 7 ,
(9) --C(O)OR 9 ,
(10) --C(O)NR 7 R 8 ,
(11) --C(O)R 7 ,
(12) --S(O) k R 7 ,
(13) --S(O) 2 NR 7 R 8 ,
(14) halo selected from F, Cl, Br and I,
(15) --CF 3 ,
(16) C(═NR 7 )--NHR 8 ,
(17) hetero C 5-10 cycloalkyl, wherein the hetero C 5-10 cycloalkyl optionally contains 1 or 2 heteroatoms selected from S, O and N,
(18) aryl, selected from phenyl or naphthyl,
(19) heteroaryl, wherein heteroaryl is selected from the group consisting of:
(a) imidazolyl,
(b) isooxazolyl,
(c) isothiazolyl,
(d) oxadiazolyl,
(e) oxazolyl,
(f) pyridyl,
(g) tetrazolyl,
(h) thiazolyl,
(i) thienyl, and
(j) triazolyl,
or when two members of the group R 1 , R 2 , R 3 and R 4 including the optional substituents present thereon reside on the same carbon atom of Formula I, or two of the group R 1 , R 2 , R 3 and R 4 including the optional substituents present thereon reside on adjacent atoms of Formula I, said two members may optionally be joined, such that together with the carbon atom to which they are attached there is formed a saturated or unsaturated monocyclic ring of 5, 6 or 7 atoms, said monocyclic ring optionally containing up to three hetero atoms selected from N, O or S,
or when a member of the group R 1 , R 2 , R 3 and R 4 including the optional substituents present thereon resides on an atom adjacent to the N on which R 6 resides, said member may optionally be joined with R 6 , such that together with the N on which R 6 resides and the carbon on which said member resides there is formed a saturated or unsaturated monocyclic heterocycle of 5, 6 or 7 atoms, said monocycle optionally containing up to three hetero atoms selected from N, O or S,
R 5 is selected from the group consisting of
(a) hydrogen,
(b) linear and branched C 1-12 alkyl, optionally mono or di- substituted, the substituents being independently selected from
(1) hydroxy,
(2) carboxy,
(3) --NR 7 R 8 ,
(4) --OR 7 ,
(5) --C(O)OR 7 ,
(6) --S(O) k R 7 ,
(7) halo selected from F, Cl, Br and I,
(8) --CF 3 ,
(9) phenyl, optionally mono or di- substituted with hydroxy, halo, C 1-4 alkyl, or C 1-4 alkoxy,
(c) --C(O)NR 10 R 11 , where R 10 and R 11 are each independently hydrogen, phenyl, cyclohexyl, --S(O) 2 NR 7 R 8 or optionally substituted C 1-6 alkyl, wherein the substituent is selected from
(1) --NR 12 R 13 , wherein R 12 and R 13 are each independently H, C 1-6 alkyl, phenyl or benzyl,
(2) --OR 12 ,
(3) --C(O)OR 12 ,
(4) --S(O) k R 12 , where k is 0, 1 or 2,
(5) halo selected from F, Cl, Br and I,
(6) optionally substituted aryl wherein aryl and aryl substituents are as defined above,
(7) optionally substituted heteroaryl wherein heteroaryl and heteroaryl substituents are as defined above,
(8) optionally substituted C 5-10 cycloalkyl wherein cycloalkyl and cycloalkyl substituents are as defined above,
(9) hetero C 5-10 cycloalkyl, wherein the hetero C 5-10 cycloalkyl optionally contains 1 or 2 heteroatoms selected from S, O and N,
(d) --C(O)R 11 ,
(e) --C(O)OR 11 ,
(f) aryl, selected from phenyl or naphthyl,
(g) cyclohexyl.
Within this embodiment there is a genus of compounds wherein
R 1 , R 2 , R 3 and R 4 are each independently selected from the group consisting of
(a) hydrogen,
(b) hydroxy,
(c) amino,
(d) cyano,
(e) fluoro, chloro, bromo, and iodo,
(f) trifluoromethyl,
(g) C 1-6 alkyl,
(h) C 1-6 alkoxy,
(i) C 1-6 alkylthio,
(j) C 1-6 alkylcarbonyl,
(k) mono- and di-C 1-6 alkylamino,
(1) aryl, where aryl is phenyl and naphthyl,
(m) aryloxy, where aryl is phenyl and naphthyl,
(n) cycloalkyl,wherein the cycloalkyl is a 5-, 6-, or 7-membered monocyclic ring which optionally contains 1 or 2 heteroatoms selected from S, O and N, and
(o) heteroaryl, wherein heteroaryl is selected from the group consisting of:
(1) pyridyl,
(2) furanyl,
(3) thienyl,
(4) pyrazinyl,
(5) pyrimidyl,
(6) thiazolyl, and
(7) triazolyl,
each of (g) to (o) being optionally mono- or di- substituted, the substituents being independently selected from
(1) hydroxy,
(2) C 1-4 alkyl,
(3) C 1-3 alkoxy,
(4) amino,
(5) mono- and di-C 1-6 alkylamino,
(6) carboxyl,
(7) C 1-3 alkylthio,
(8) C 1-3 alkyl-S(O) k --, where k is 1 or 2,
(9) C 1-4 alkoxycarbonyl,
(10) halo selected from fluoro, chloro, bromo, and iodo,
(11) oxo, and
(12) amidino,
R 5 is selected from the group consisting of
(a) hydrogen,
(b) C 1-6 alkylcarbonyl,
(c) arylcarbonyl, wherein the aryl group is phenyl,
(d) arylcarbonyl-aminocarbonyl, wherein the aryl group is phenyl and naphthyl,
(e) R 6 R 7 N--SO 2 --NH--C(═O)--, wherein R 6 and R 7 are independently selected from the group consisting of
(1) hydrogen,
(2) C 1-6 alkyl,
(3) aryl, wherein the aryl group is selected from phenyl, and
(4) R 6 and R 7 may be joined together to form a 5-, 6- or 7-membered ring containing 0, 1 or 2 heteroatoms, the heteroatoms being elected from the group of oxygen, sulfur and nitrogen,
each of (b) to (e) being mono- or di- substituted, the substituents being independently selected from
(1) hydroxy,
(2) C 1-3 alkoxy,
(3) amino,
(4) mono- and di-C 1-6 alkylamino,
(5) carboxyl,
(6) C 1-3 alkylthio,
(7) C 1-3 alkyl-S(O) k --, where k is 1 or 2,
(8) C 1-4 alkoxycarbonyl,
(9) halo selected from fluoro, chloro, bromo, and iodo,
(10) oxo, and
(11) amidino.
Within this genus there is a class of compounds wherein R 1 , R 2 , R 3 and R 4 are each independently selected from the group consisting of
(a) hydrogen,
(b) hydroxy,
(c) amino,
(d) cyano,
(e) fluoro, chloro or bromo,
(f) trifluoromethyl,
(g) C 1-4 alkyl,
(h) C 1-4 alkoxy,
(i) C 1-4 alkylthio, and
(j) mono- and di-C 1-4 alkylamino,
R 5 is selected from the group consisting of
(a) hydrogen
(b) R 6 R 7 N--SO 2 --NH--C(═O)--, optionally mono or di- substituted, wherein R 6 and R 7 are independently selected from the group consisting of
(1) hydrogen,
(2) C 1-4 alkyl, and
(3) aryl, wherein the aryl group is phenyl, and
said substituents are independently selected from
(1) hydroxy,
(2) C 1-3 alkoxy,
(3) amino,
(4) mono- and di-C 1-6 alkylamino,
(5) carboxyl,
(6) C 1-3 alkylthio, and
(7) halo selected from fluoro, chloro, and bromo.
Within this class there is a sub-class of compounds wherein wherein
R 2 is hydrogen or methyl;
R 4 is hydrogen or methyl;
R 1 and R 3 are each independently selected from
(a) hydrogen,
(b) methyl, ethyl, propyl or butyl,
(c) chloro,
(d) --CN, and
(e) --CF 3 ; and
R 5 is hydrogen.
Illustrating the invention are:
(a) hexahydro-5-imino-(1H)-1,4-diazepine dihydrochloride,
(b) hexahydro-5-imino-1,4-thiazepine hydrochloride
(c) hexahydro-5-imino-1,4-oxazepine hydrochloride,
(d) hexahydro-5-imino-3-propyl-1,4-thiazepine hydrochloride,
(e) hexahydro-5-imino-6propyl-1,4-thiazepine hydrochloride,
(f) hexahydro-5-imino-7-methyl-1,4-thiazepine hydrochloride,
(g) hexahydro-5-imino-2-methyl-1,4-thiazepine hydrochloride,
(h) hexahydro-5-imino-6-(3-methyl-2-n-butenyl)-1,4-thiazepine hydrochloride,
(i) hexahydro-5-imino-3-(3-methyl-2-n-butenyl)-1,4-thiazepine hydrochloride,
(j) hexahydro-5-imino-6-(2-methyl-propyl)-1,4-thiazepine hydrochloride,
(k) hexahydro-5-imino-3-(2-methyl-propyl)-1,4-thiazepine hydrochloride,
(l) hexahydro-5-imino-6-methyl-1,4-thiazepine hydrochloride,
(m) hexahydro-5-imino-3-methyl-1,4-thiazepine hydrochloride,
(n) hexahydro-5-imino-3-ethyl-1,4-thiazepine hydrochloride,
(o) hexahydro-5-imino-3-butyl-1,4-thiazepine hydrochloride,
(p) hexahydro-5-imino-3-(2-methyl-3-propenyl)-1,4-thiazepine hydrochloride,
(q) (±)-trans-decahydro-4-imino-benzo[b]-1,4-thiazepine acetic acid salt,
(r) hexahydro-5-imino-3(S)-propyl-1,4-thiazepine acetic acid salt,
(s) hexahydro-5-imino-3(R)-propyl-1,4-thiazepine acetic acid salt,
(t) hexahydro-5-imino-1-methyl-(1H)-1,4-diazepine hydrochloride,
and pharmaceutically acceptable salts thereof.
For purposes of this specification alkyl is defined to include linear, branched, and cyclic structures, with C 1-6 alkyl including methyl, ethyl, propyl, 2-propyl, s- and t-butyl, butyl, pentyl, hexyl, cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. Similarly, C 1-6 alkoxy is intended to include alkoxy groups of from 1 to 6 carbon atoms of a straight, branched, or cyclic configuration. Examples of lower alkoxy groups include methoxy, ethoxy, propoxy, isopropoxy, cyclopropyloxy, cyclohexyloxy, and the like. Likewise, C 1-6 alkylthio is intended to include alkylthio groups of from 1 to 6 carbon atoms of a straight, branched or cyclic configuration. Examples of lower alkylthio groups include methylthio, propylthio, isopropylthio, cycloheptylthio, etc. By way of illustration, the propylthio group signifies --SCH 2 CH 2 CH 3 .
Heteroaryl includes furan, benzofuran, thiophene, pyrrole, indole, isoxazole, isothiazole, pyrazole, oxazole, benzoxazole, thiazole, imidazole, benzimidazole, 1,2,3-oxadiazole, 1,2,3-thiadiazole, 1,2,3-triazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole, 1,3,4-triazole, 1,2,5-oxadiazole, 1,2,5-thiadiazole, pyridine, quinoline, isoquinoline, pyridazine, pyrimidine, pyrazine, 1,2,4-triazine, 1,3,5-triazine, 1,2,4,5-tetrazine, tetrazole, and the like.
As appreciated by those of skill in the art, the depiction ##STR3## is intented to indicate that substituents R 1 , R 2 , R 3 and R 4 may each independently reside at any available position on the ring structure of figure I.
Illustrative of the situation wherein two members of R 1 , R 2 , R 3 and R 4 are joined together to form a ring or one member is joined together with R 6 to form a ring include the following: ##STR4##
As outlined in the summary of the invention, the compounds of the instant invention are useful in the treatment of a number of NOS implicated diseases. The implication of these diseases is well documented in the literature. For example, with regard to psoriasis, see Ruzicka et. al., J. Invest. Derm., 103: 397 (1994) or Kolb-Bachofen et. al., Lancet, 344: 139 (1994) or Bull, et al., J. Invest. Derm., 103: 435(1994); with regard to uveitis, see Mandia et. al., Invest Opthalmol., 35: 3673-89 (1994); with regard to type 1 diabetes, see Eisieik & Leijersfam, Diabetes & Metabolism, 20: 116-22 (1994) or Kroncke et. al., BBRC, 175: 752-8 (1991) or Welsh et. al., Endocrinol., 129: 3167-73 (1991); with regard to septic shock, see Petros et. al., Lancet, 338: 1557-8 (1991),Thiemermann & Vane, Eur. J. Pharmacol., 211: 172-82 (1992), or Evans et. al., Infec. Imm., 60: 4133-9 (1992), or Schilling et. al., Intensive Care Med., 19: 227-231 (1993); with regards to pain, see Moore et. al., Brit. J. Pharmacol., 102: 198-202 (1991), or Moore et. al, Brit. J. Pharmacol., 108: 296-97 (1992) or Meller et. al., Europ. J. Pharmacol, 214: 93-6 (1992) or Lee et. al., NeuroReport, 3: 841-4 (1992); with regard to migraine, see Olesen et. al., TIPS, 15: 149-153 (1994); with regard to rheumatoid arthritis, see Kaurs & Halliwell, FEBS Letters, 350: 9-12 (1994); with regard to osteoarthritis, see Stadler et. al., J. Immunol, 147: 3915-20 (1991); with regard to inflammatory bowel disease, see Miller et. al., Lancet, 34: 465-66 (1993) or Miller et. al., J. Pharmacol. Exp. Ther., 264: 11-16 (1993); with regard to asthma, see Hamid et. al., Lancet, 342: 1510-13 (1993) or Kharitonov, et. al., Lancet, 343: 133-5 (1994); with regard to Immune complex diseases, see Mulligan et. al., Br. J. Pharmacol., 107: 1159-62 (1992); with regard to multiple sclerosis, see Koprowski et. al., PNAS, 90: 3024-7 (1993); with regard to ischemic brain edema, see Nagafuji et. al., Neurosci., 147: 159-62 (1992) or Buisson et. al., Br. J. Pharmacol., 106: 766-67 (1992) or Trifiletti et. al., Europ. J. Pharmacol., 218: 197-8 (1992); with regard to toxic shock syndrome, see Zembowicz & Vane, PNAS, 89: 2051-55 (1992); with regard to heart failure, see Winlaw et. al., Lancet, 344: 373-4 (1994); with regard to ulcerative colitis, see Boughton-Smith et. al., Lancet 342: 338-40 (1993); and with regard to atherosclerosis, see White et. al., PNAS, 91: 1044-8 (1994); with regard to glomerulonephritis, see Muhl et. al., Br. J. Pharmcol., 112: 1-8 (1994); with regard to paget's disease and osteoporosis, see Lowick et. al., J. Clin. Invest., 93: 1465-72 (1994) or Evans et al., Clin. Orthopaedics & Related Res., 312: 275-294 (1995); with regard to inflammatory sequelae of viral infections, see Koprowski et. al., PNAS, 90: 3024-7 (1993); with regard to retinitis, see Goureau et. al., BBRC, 186: 854-9 (1992); with regard to oxidant induced lung injury, see Berisha et. al., PNAS, 91, 744-9 (1994); with regard to eczema, see Ruzica, et al., J. Invest. Derm., 103, 395(1994); with regard to acute allograft rejection, see Devlin, J. et al., Transplantation, 58, 592-595 (1994); with regard to infection caused by invasive microorganisms which produce NO, see Chen, Y. and Rosazza, J. P. N., Biochem. Biophys. Res. Comm., 203: 1251-1258(1994); and with regard to tumor growth, see Jenkins et al., PNAS, 92, 4392-4396 (1995).
The pharmaceutical compositions of the present invention comprise a compound of Formula I as an active ingredient or a pharmaceutically acceptable salt, thereof, and may also contain a pharmaceutically acceptable carrier and optionally other therapeutic ingredients. The term "pharmaceutically acceptable salts" refers to salts prepared from pharmaceutically acceptable non-toxic acids or bases including inorganic bases and organic bases. Salts derived from inorganic acids include aluminum, ammonium, calcium, copper, ferric, ferrous, lithium, magnesium, manganic salts, manganous, potassium, sodium, zinc, and the like. Particularly preferred are the ammonium, calcium, magnesium, potassium, and sodium salts. Salts derived from pharmaceutically acceptable organic non-toxic bases include salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines, and basic ion exchange resins, such as arginine, betaine, caffeine, choline, N,N -- -dibenzylethylenediamine, diethylamine, 2-diethylaminoethanol, 2-dimethylaminoethanol, ethanolamine, ethylenediamine, N-ethylmorpholine, N-ethylpiperidine, glucamine, glucosamine, histidine, hydrabamine, isopropylamine, lysine, methylglucamine, morpholine, piperazine, piperidine, polyamine resins, procaine, purines, theobromine, triethylamine, trimethylamine, tripropylamine, tromethamine, and the like.
It will be understood that in the discussion of methods of treatment which follows, references to the compounds of Formula I are meant to also include the pharmaceutically acceptable salts.
The pharmaceutical compositions containing the active ingredient of the instant invention 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 to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of sweetening agents, flavoring agents, coloring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets contain the active ingredient in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of tablets. These excipients may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example, corn starch, or alginic acid; binding agents, for example starch, gelatin or acacia, and lubricating agents, for example, 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. They may also be coated by the technique described in the U.S. Pat. Nos. 4,256,108; 4,166,452; and 4,265,874 to form osmotic therapeutic tablets for control release.
Formulations for oral use may also be presented as hard gelatin capsules wherein the active ingredient is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example peanut oil, liquid paraffin, or olive oil.
Aqueous suspensions contain the active material in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethyl-cellulose, methylcellulose, hydroxypropylmethycellulose, sodium alginate, polyvinyl-pyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be a naturally-occurring phosphatide, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethylene-oxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example polyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives, for example ethyl, or n-propyl, p-hydroxybenzoate, one or more coloring agents, one or more flavoring agents, and one or more sweetening agents, such as sucrose, saccharin or aspartame.
Oily suspensions may be formulated by suspending the active ingredient in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in mineral oil such as liquid paraffin. The oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set forth above, and flavoring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an anti-oxidant such as ascorbic acid.
Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional excipients, for example sweetening, flavoring and coloring agents, may also be present.
The pharmaceutical compositions of the invention may also be in the form of an oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oil, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally-occurring phosphatides, for example soy beans, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan monooleate, and condensation products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening and flavouring agents.
Syrups and elixirs may be formulated with sweetening agents, for example glycerol, propylene glycol, sorbitol or sucrose. Such formulations may also contain a demulcent, a preservative and flavoring and coloring agents. The pharmaceutical compositions may be in the form of a sterile injectable aqueous or oleagenous suspension. This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above. 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-butane diol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, 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. In addition, fatty acids such as oleic acid find use in the preparation of injectables.
Compounds of formula I may also be administered in the form of a suppositories for rectal administration of the drug. These compositions can be prepared by mixing the drug with a suitable non-irritating excipient which is solid at ordinary temperatures but liquid at the rectal temperature and will therefore melt in the rectum to release the drug. Such materials are cocoa butter and polyethylene glycols.
For topical use, creams, ointments, jellies, solutions or suspensions, etc., containing the compound of Formula I are employed. (For purposes of this application, topical application shall include mouth washes and gargles.)
Dosage levels of the order of from about 0.01 mg to about 140 mg/kg of body weight per day are useful in the treatment of the above-indicated conditions, or alternatively about 0.5 mg to about 7 g per patient per day. For example, inflammation may be effectively treated by the administration of from about 0.01 to 50 mg of the compound per kilogram of body weight per day, or alternatively about 0.5 mg to about 3.5 g per patient per day, preferably 2.5 mg to 1 g per patient per day.
The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. For example, a formulation intended for the oral administration of humans may contain from 0.5 mg to 5 g of active agent compounded with an appropriate and convenient amount of carrier material which may vary from about 5 to about 95 percent of the total composition. Dosage unit forms will generally contain between from about 1 mg to about 500 mg of an active ingredient, typically 25 mg, 50 mg, 100 mg, 200 mg, 300 mg, 400 mg, 500 mg, 600 mg, 800 mg, or 1000 mg.
It will be understood, however, that the specific dose level for any particular patient will depend upon a variety of factors including the age, body weight, general health, sex, diet, time of administration, route of administration, rate of excretion, drug combination and the severity of the particular disease undergoing therapy.
Assay Protocol for NOS Activity
NOS activity is measured as the formation of L-[2,3,4,5- 3 H]Citrulline from L-[2,3,4,5- 3 H]Arginine. The incubation buffer (100 uL) contained; 100 mM TES, pH 7.5, 5 uM FAD, 5 uM FMN, 10 uM BH 4 , 0.5 mM NADPH, 0.5 mM DTT, 0.5 mg/mL BSA, 2 mM CaC12, 10 ug/mL calmodulin (bovine), 1 uM L-Arg, 0.2 uCi L-[2,3,4,5- 3 H]Arg, and the inhibitor in aqueous DMSO (max. 5%). The reaction is initiated by addition of enzyme. Incubations are performed at room temperature for 30 minutes and stopped by the addition of an equal volume of quenching buffer consisting of 200 mM sodium citrate, pH 2.2, 0.02% sodium azide. Reaction products are separated by passing through a cation exchange resin and quantitated as cpm by scintillation counting. Percent inhibition is calculated relative to enzyme incubated without inhibitor according to: % inhibition=100×(cpm L-[2,3,4,5- 3 H]Cit with inhibitor/cpm L-[2,3,4,5- 3 H]Cit without inhibitor).
Illustrative of the utility of the compounds of Formula I is the ability of such compounds to inhibit NO synthase as shown in Table 1 and as measured by the assay described above:
TABLE 1______________________________________Inhibition of Nitric Oxide Synthase IsozymesExample iNOS ecNOS ncNOS Number (IC.sub.50, uM) (IC.sub.50, uM) (IC.sub.50, uM)______________________________________1 >50 >50 >50 2 <10 >10 <10 3 <50 <50 <10 4 <1 <50 <10 5 >50 >50 >50 6 <10 <10 <1 7 <10 <10 <1 8 >50 >50 >50 9 <1 >50 <50 10 <50 >50 >50 11 <1 >50 <10 12 >50 <50 <10 13 <1 <10 <10 14 <1 <50 <10 15 <1 >50 <10 16 <1 <50 <10 17 >50 >50 >50 18 <1 <10 <1 19 <10 <50 <10 20 <50 >50 >50______________________________________
Methods of Synthesis
The compounds of the present invention can be prepared according to the following methods. ##STR5##
As shown in Scheme 1, hexahydro-1-(phenylmethyl)-(5H)-1,4-diazepin-5-one A (prepared as described by T. Irikura, CAS 84: 31153r, 83: 179149u) is reacted under hydrogen atmosphere at 40 psi in the presence of palladium hydroxide catalyst in ethanol and acetic acid to give hexahydro-5H-1,4-diazepin-5-one B as the acetic acid salt. Reaction with di-t-butyl dicarbonate in the presence of sodium chloride and sodium hydroxide gives 1-(tert-butyloxycarbonyl)-hexahydro-(5H)-1,4-diazepin-5-one C. The imino ether D is formed from C by reaction with Meerwein's salt (trimethyloxonium fluoroborate). The amidine E is obtained by reaction of D with ammonium chloride in refluxing ethanol. The amine protecting group in E is removed by reaction with hydrogen chloride in ethyl acetate to give the desired amidine F as the dihydrochloride salt. ##STR6##
An alternative preparation of the amidine functionality is shown in Scheme 2. A thioamide A is reacted directly with ammonia in the presence of mercuric chloride to give the 5-imino-1,4-diazepine B. ##STR7##
1,4-Oxa- and thiazepine analogs are prepared by methodology outline in Scheme 3. A ketone derivative A is converted to its corresponding oxime B by reaction with hydroxylamine in ethanol. Ring expansion of B via a Beckmann rearrangement of the O-tosyl-oxime formed by reaction of B with with butyl lithium and p-toluenesulfonyl chloride gives hexahydro-1,4-heteroazepin-5-one C. When X=S, the amide in C is converted to the thioamide D by reaction with Lawesson's reagent. Reaction of D with Meerwein's salt to form the imino-thioether followed by reaction with ammonium chloride gives the hexahydro-5-imino-1,4-heteroazepine E. Alternatively, when X=O in C, reaction with Meerwein's salt followed by ammonium chloride gives E directly. ##STR8##
More highly substituted hexahydro-5-imino-1,4-heteroazepines may be prepared according to methodology outlined in Scheme 4. Diester A is cyclized via a Dieckmann condensation to keto-ester B. Treatment of B with a strong base such as sodium hydride followed by addition of an alkylating agent such as n-propyl iodide will give E (where R 2 is hydrogen and R 3 is n-propyl). Alternatively, keto-ester B may be oxidized by manganese dioxide to form the α,β-unsaturated keto-ester C. A substituent R 2 is introduced via a Michael reaction with an organo-cuprate reagent to form D. Alkylation of D with (R 3 )X in the presence of a strong base will form E (R 2 and R 3 are not hydrogen). Deesterification-decarboxylation of E will form F. By procedures outlined in Scheme 3, F is converted to amides H and I via Beckmann rearrangement of oxime G. Since the Beckmann rearrangement can occur with migration to either side of the oxime, the two amides H and I may be formed. These amides H and I may be separated chromatographically at this point or, alternatively, may be subsequently converted to their respective thioamides by reaction with Lawesson's reagent and then separated. Reaction of the thioamides from H and I with Meerwein's salt followed by treatment with ammonium chloride will give substituted hexahydro-5-imino-1,4-heteroazepines J and K. When X is nitrogen, a appropriate amine protecting group (eg., tert-butyloxycarbonyl) may be employed in the reaction sequence. ##STR9##
More highly substituted hexahydro-5-imino-1,4-heteroazepines may also be prepared according to methodology outlined in Scheme 5. Briefly, the amine functionality in aminoalcohol A is protected to give B. Mitsunobu conditions will cyclize B to form aziridine C. The aziridine ring in C is opened with β-mercaptopropionic acid followed by treatment with hydrochloric acid in ethyl acetate to yield amino acid D. Reaction of D under standard peptide bond forming reactions gives lactam E. Reaction with Lawesson's reagent gives the thiolactam F which is converted to 5-imino-1,4-thiazepine G by previously described conditions.
The invention will now be illustrated by the following non-limiting examples in which, unless stated otherwise:
all operations were carried out at room or ambient temperature, that is, at a temperature in the range 18-25° C.; evaporation of solvent was carried out using a rotary evaporator under reduced pressure (600-4000 pascals: 4.5-30 mm. Hg) with a bath temperature of up to 60° C.; the course of reactions was followed by thin layer chromatography (TLC) and reaction times are given for illustration only; melting points are uncorrected and `d` indicates decomposition; the melting points given are those obtained for the materials prepared as described; polymorphism may result in isolation of materials with different melting points in some preparations; the structure and purity of all final products were assured by at least one of the following techniques: TLC, mass spectrometry, nuclear magnetic resonance (NMR) spectrometry or microanalytical data; yields are given for illustration only; when given, NMR data is in the form of delta (δ) values for major diagnostic protons, given in parts per million (ppm) relative to tetramethylsilane (TMS) as internal standard, determined at 400 MHz or 500 MHz using the indicated solvent; conventional abbreviations used for signal shape are: s. singlet; d. doublet; t. triplet; m. multiplet; br. broad; etc.: in addition "Ar" signifies an aromatic signal; chemical symbols have their usual meanings; the following abbreviations have also been used v (volume), w (weight), b.p. (boiling point), m.p. (melting point), L (liter(s)), ML (milliliters), g (gram(s)), mg (milligrams(s)), mol (moles), mmol (millimoles), eq (equivalent(s)).
EXAMPLE 1 ##STR10##
Hexahydro-5-imino-(1H)-1,4-diazepine dihydrochloride
Step A: Hexahydro-(5H)-1,4-diazepine-5-one acetic acid salt
1-Benzylhexahydro-(5H)-1,4-diazepine-5-one (1.5 g, 7.34 mmol) was dissolved in 12 mL of ethanol and 6 mL of acetic acid. After addition of 150 mg of 20% palladium hydroxide on carbon, the mixture was shaken under 40 psi of hydrogen for 4 h. The resulting mixture was centrifuged and the supernatant was filtered through a 0.45 micron membrane filter. The catalyst was washed with ethanol (3×10 mL), and the combined filtrate was concentrated in vacuo to give a yellow oil which began to crystallize. Swirling with 2 mL of methanol and 1 mL of ethyl acetate facilitated the crystallization, and evaporation of the solvent in vacuo gave 1.23 g (96%) of hexahydro-(5H)-1,4-diazepin-5-one acetic acid salt as light yellow crystals.
1 H NMR (400 MHz, CD 3 OD): δ3.44-3.40 (m, 2H), 3.19-3.15 (m, 2H), 3.15-3.11 (m, 2H), 2.74-2.70 (m, 2H), 1.94 (s, 3H).
Mass spectrum: m/z=115 (M+1, 100%).
Step B: 1-(tert-Butoxycarbonyl)hexahydro-(5H)-1,4-diazepin-5-one
A mixture of hexahydro-(5H)-1,4-diazepin-5-one acetic acid salt (200 mg, 1.15 mmol), di-tert-butyldicarbonate (277 mg, 1.27 mmol) and sodium chloride (460 mg, 7.93 mmol) in 2.0 mL of chloroform was stirred and 2.5 N aqueous sodium hydroxide (460 uL, 1.15 mmol) was added. The mixture was heated to reflux for 4 h, and then extracted with 3×10 mL of-ethyl acetate. The combined ethyl acetate extracts were dried over anhydrous sodium sulfate, decanted and evaporated in vacuo to give 219 mg (89%) of 1-(tert-butoxycarbonyl)hexahydro-(5H)-1,4-diazepin-5-one as a white solid.
1 H NMR (400 MHz, CD 3 OD): δ3.60-3.53 (m, 4H), 3.28-3.25 (m, 2H), 2.61-2.56 (m, 2H), 1.47 (s, 9H).
Mass spectrum: m/z=215 (M+1, 100%). Anal. calcd for C 10 H 18 N 2 O 3 : C, 56.32; H, 8.04; N, 13.14. Found: C, 55.92; H, 8.48; N, 13.00.
Step C: 1-(tert-Butoxycarbonyl)-2,3,6,7-tetrahydro-5-methoxy-(1H)-1,4-diazepine
Trimethyloxonium tetrafluoroborate (Meerwein's salt) (141 mg, 0.94 mmol) was added in one portion to a solution of 1-(tert-butoxycarbonyl)hexahydro-(5H)-1,4-diazepin-5-one (200 mg, 0.94 mmol) in 2.0 mL of anhydrous methylene chloride. The mixture was stirred overnight at room temperature. The reaction mixture was partitioned between 10 mL of saturated aqueous sodium bicarbonate and 20 mL of ethyl acetate. The organic layer was separated and the aqueous layer was extracted with 3×10 mL of ethyl acetate. The combined ethyl acetate layers were washed with saturated aqueous sodium bicarbonate and saturated aqueous sodium chloride. After drying over anhydrous sodium sulfate, the organic solution was concentrated in vacuo to give 180 mg (85%) of 1-(tert-butoxycarbonyl)-2,3,6,7-tetrahydro-5-methoxy-(1H)-1,4-diazepine as a yellow liquid.
1 H NMR(400 MHz, CD 3 OD): δ3.58 (s, 3H), 3.53-3.45 (m, 6H), 2.63-2.59 (m, 2H), 1.46 (s, 9H).
Mass spectrum: m/z=129.
Step D: 1-(tert-Butoxycarbonyl)-hexahydro-5-imino-(1H)-1,4-diazepine hydrochloride
A mixture of 1-(tert-butoxycarbonyl)-2,3,6,7-tetrahydro-5-methoxy-(1H)-1,4-diazepine (170 mg, 0.75 mmol) and ammonium chloride (40.1 mg, 0.75 mmol) in 2.0 mL of anhydrous ethanol was refluxed for 3 h. The solvent was then removed in vacuo and residue was triturated with 3×10 mL of ether to give 174 mg of 1-(tert-butoxycarbonyl)-hexahydro-5-imino-(1H)-1,4-diazepine hydrochloride as a light yellow solid.
1 H NMR (400 MHz,CD 3 OD): δ3.71-3.65 (m, 2H), 3.63-3.57 (m, 2H), 3.55-3.50 (m, 2H), 2.90-2.86 (m, 2H), 1.47 (s, 9H).
Mass spectrum: m/z=214 (M+1, 100%).
Step E: Hexahydro-5-Imino-(1H)-1,4-diazepine dihydrochloride
Hydrogen chloride gas (2.0 g, 55 mmol) was bubbled into 15 mL of ethyl acetate at 0° C. over 3 min. 1-(tert-Butoxycarbonyl)-5-iminohexahydro-(1H)-1,4-diazepine hydrochloride (85 mg, 0.34 mmol ) was added and mixture was stirred at room overnight. Removal of solvent and hydrogen chloride in vacuo gave 60 mg (95%) of hexahydro-5-imino-(1H)-1,4-diazepine dihydrochloride as a yellow solid.
1 H NMR (400 MHz, CD 3 OD): δ3.84-3.80 (m, 2H), 3.55-3.50 (m, 2H), 3.43-3.39 (m, 2H), 3.21-3.16 (m, 2H).
Mass spectrum: m/z=114 (M-2HCl+1, 100%). Anal. calcd for C 5 H 13 N 3 Cl 2 : C, 32.27; H, 7.04; N, 22.58; Cl, 38.10. Found: C, 32.09; H, 7.04; N, 21.67; Cl, 38.05.
EXAMPLE 2 ##STR11##
Hexahydro-5-imino-1,4-thiazepine hydrochloride
Step A: 4-Oximino-tetrahydrothiopyran
To a stirring solution of solution of tetrahydrothiopyran-4-one (4.9 g, 42.1 mmol) and hydroxylamine hydrochloride (5.9 g, 84 mmol) in 35 mL of ethanol at 0° C. was added a solution of sodium hydroxide (3.38 g, 84.5 mmol) dissolved in 13 mL water. The reaction mixture was warmed to room temperature and stirred for an additional 2 h. The ethanol was removed in vacuo and the aqueous solution extracted with ether (2×250 mL). The etheral layer was washed with with water, saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was evaporated to give crude oxime which was recrystallized from hexane/ether to give 4.66 g of 4-oximino-tetrahydrothiopyran.
1 H NMR (500 MHz, CDCl 3 ): δ9.43 (brs, 1H), 2.86 (m, 2H), 2.78(m, 2H), 2.73 (m, 2H), 2.56 (m, 2H).
13 C NMR (125 MHz, CDCl 3 ): δ158.24, 33.94, 29.75, 28.38, 26.78.
Step B: Tetrahydro-(2H)-1,4-thiazepin-5-one
To a solution of 4-oximino-tetrahydrothiopyran (1.0 g, 7.6 mmol) in 20 mL of dry ether under nitrogen atmosphere at 0° C. was added n-butyllithium (5.0 mL of a 1.6 M solution in hexane, 8.0 mmol). The resulting white suspension was stirred at 0° C. for one hour at which point a solution of p-toluenesulfonyl chloride (1.52 g, 8.0 mmol) in 10 mL ether was added and the reaction mixture stirred for 4 h at 5° C. The solvent was removed in vacuo and then the residue was treated with 20 mL of 70% dioxane containing five drops of triethylamine and stirred for 24 h at room temperature. The solvent was removed in vacuo and the residue was extracted with methylene chloride. The methylene chloride layer was washed with water, saturated sodium chloride and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo and the product purified by flash column chromatography on silica gel eluted with hexane/ethyl acetate (7:3) to give 0.13 g of hexahydro-(1H)-1,4-thiazepin-5-one.
1 H NMR (500 MHz, CDCl 3 ): δ6.92 (brs, 1H), 3.61 (m, 2H), 2.92(m, 2H), 2.74 (m, 2H), 2.70 (m, 2H).
13 C NMR (125 MHZ, CDCl 3 ): δ177.76, 45.88, 40.95, 31.54, 24.61.
Step C: Tetrahydro-(2H)-1,4-thiazepin-5-thione
To a solution of tetrahydro-(2H)-1,4-thiazepin-5-one (0.335 g, 2 mmol) in 5 mL of dry toluene was added Lawesson's reagent [2,4-bis(4-methoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide] (0.971 g , 2.4 mmol) and the mixture was stirred at 90° C. for 30 mins. Evaporation of the solvent in vacuo followed by purification by flash column chromatography on silica gel eluted with methylene chloride:ethyl acetate (19:1) gave 0.365 g of tetrahydro-(2H)-1,4-thiazepin-5-thione. 1 H NMR (500 MHz, CDCl 3 ): δ9.19 (brs, 1H), 3.80 (m, 2H), 3.44 (m, 2H), 2.78 (m, 2H), 2.71 (m, 2H).
13 C NMR (125 MHZ, CDCl 3 ): δ208.90, 50.39, 49.02, 29.54, 25.86.
Step D: Hexahydro-5-imino-1,4-thiazepine hydrochloride
To a solution of tetrahydro-(2H)-1,4-thiazepin-5-thione (90 mg, 0.5 mmol) in 2 mL of dry methylene chloride at room temperature was added trimethyloxonium tetrafluoroborate (Meerwein's salt) (88 mg, 0.6 mmol) followed by diisopropylethylamine (77 mg, 0.6 mmol). The resulting mixture was stirred at room temperature for 2 h. The methylene chloride layer was washed with water, saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo to give the crude imino-ether which was subsequently treated with ammonium chloride (0. 017 g) in 3 mL of ethanol and heated at 80° C. for 15 h. Evaporation of ethanol followed by trituration of the oil with ethyl acetate and ether gave 53 mg of hexahydro-5-imino-1,4-thiazepine hydrochloride as a white solid.
1 H NMR (500 MHz, D 2 O): δ3.81 (m, 2H), 3.11 (m, 2H), 2.84 (m, 2H), 2.76 (m, 2H).
13 C NMR (125 MHz, D 2 O): δ46.88, 35.52, 28.84, 23.74.
Mass spectrum: m/z=131 (M+1).
EXAMPLE 3 ##STR12##
Hexahydro-5-imino-1,4-oxazepine hydrochloride
Step A: 4-Oximino-tetrahydropyran
Employing the procedure described in Example 2, step A, tetrahydropyran-4-one was converted to 4-oximino-tetrahydropyran.
1 H NMR (500 MHz, CDCl 3 ): δ3.82 (m, 2H), 3.77 (m, 2H), 2.68 (m, 2H), 2.39 (m, 2H).
Step B: Tetrahydro-(2H)-1,4-oxazepin-5-one
Employing the procedure in Example 2, step B, 4-oximino-tetrahydropyran was converted to tetrahydro-(2H)-1,4-oxazepin-5-one.
1 H NMR (500 MHz, CDCl 3 ): δ7.07 (brs, 1H), 3.79 (m, 2H), 3.75(m, 2H), 3.34 (m, 2H), 2.69 (m, 2H).
13 C NMR (125 MHZ, CDCl 3 ): δ177.94, 71.61, 65.52, 44.74, 41.01.
Step C: Hexahydro-5-imino-1,4-oxazepine, hydrochloride
Employing the procedure in Example 2, step D, tetrahydro-(2H)-1,4-oxazepin-5-one was reacted with Meerwien's salt and ammonium chloride to form hexahydro-5-imino-1H-1,4-oxazepine, hydrochloride.
1 H NMR (500 MHz, D 2 O): δ3.89 (m, 2H), 3.80 (m, 2H), 3.60 (m, 2H), 2.96 (m, 2H).
13 C NMR (125 MHz, D 2 O): δ69.54, 64.92, 46.12, 35.42. MS: m/z=115.1 (M + ).
EXAMPLE 4 ##STR13##
Hexahydro-5-imino-3-propyl-1,4-thiazepine hydrochloride
Step A: Tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester
A mixture of 3,3'-thiodipropionic acid (17.82 g, 10 mmol), allyl alcohol (20.4 mL, 30 mmol) and p-toluenesulfonic acid (0.750 g) in 100 mL of toluene was refluxed for 8 h in a Dean-Stark apparatus to azeotropically remove water. The reaction mixture was quenched with saturated solution of sodium bicarbonate and the toluene layer was separated and washed with saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo and gave approximately 20 g of crude 3,3'-thiodipropionic acid, diallyl ester. This material was sufficiently pure by NMR and was used in the subsequent reaction.
To a mixture of sodium hydride (60% in oil, 1.6 g, 38.7 mmol) in 10 mL of dry ether at room temperature was added allyl alcohol (2.25 g, 38.7 mmol) in a dropwise manner. The resultant mixture was stirred for 15 min. A solution of 3,3'-thiodipropionic acid, diallyl ester (5.0 g, 19.3 mmol) in 10 mL ether was slowly added and the mixture refluxed for 5 h. The reaction was cooled to room temperature and then quenched with water and the pH adjusted to 4 with 1N HCl. The ether layer was separated and the aqueous layer was extracted with ether (2×100 mL). The combined etheral layer was washed with saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was evaporated and the residue purified by flash column chromatography on silica gel eluted with hexane:ether (9:1) to give 2.57 g of tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester.
1 H NMR (500 MHz, CDCl 3 ): δ12.48 (s, 1H), 5.95 (m, 1H), 5.35 (m, 2H), 4.68 (m, 2H), 3.38 (s, 2H), 2.78 (t, J=6 Hz, 2H), 2.60 (t, J=6.1 Hz, 2H).
13 C NMR (125 MHZ, CDCl 3 ): δ172.80, 131.91, 118.48, 65.32, 30.95, 24.75, 23.58.
Step B: 3-Propyl-tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester
A solution of tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester (1.0 g, 5 mmol) in 1 mL of dimethylformamide was added to a stirred mixture of sodium hydride (60% in oil, 0.2.2 g, 5.5 mmol) and 1-iodopropane (0.934 g, 5.5 mmol) in 2.5 mL of dimethylformarnmide at 0° C. The reaction mixture was warmed to room temperature and stirred overnight. The reaction mixture was diluted with water and extracted with ether. The etheral layer was washed with saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo and the residue purified by flash column chromatography on silica gel eluted with hexane:ether (19:1) to give 0.277 g of 3-propyl-tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester.
1 H NMR (500 MHz, CDCl 3 ): δ5.93 (m, 1H), 5.27-5.38 (m, 2H), 4.70(m, 2H), 3.33-2.73 (m, 6H), 1.96-1.20(m, 4H), 0.93 (t, J=6.3 Hz, 3H).
13 C NMR (125 MHZ, CDCl 3 ): δ205.44, 170.83, 131.36, 119.10, 66.05, 63.14, 43.33, 38.66, 36.66, 30.93, 18.01, 14.48.
Step C: 3-Propyl-tetrahydrothiopyran-4-one
To a stirred solution of 3-propyl-tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester (0.272 g, 1.1 mmol) in 5.0 mL dry tetrahydrofuran at room temperature was successively added morpholine (0.979 g, 1.12 mmol) followed by tetrakis(triphenylphosphine)palladium(0) (0.064 g, 0.055 mmol). Stirring was continued until the thin layer chromatography indicated the completion of reaction at which point the reaction mixture was evaporated and the crude product was purified by flash column chromatography on silica gel eluted eluted with hexane:ether (19:1) to give 0.163 g of 3-propyl-tetrahydrothiopyran-4-one.
1 H NMR (500 MHz, CDCl 3 ): δ3.02-2.94 (m, 7H), 1.88-1.29 (m, 4H), 0.93 (t, J=7.1 Hz, 3H).
13 C NMR (125 MHZ, CDCl 3 ): δ210.61, 52.77, 43.82, 35.92, 31.58, 31.06, 20.19, 14.13.
Step D: 4-Oximino-3-propyl-tetrahydrothiopyran
Employing the procedure described in Example 2, step A, 3-propyl-tetrahydrothiopyran-4-one was reacted with hydroxylamine hydrochloride to form 4-oximino-3-propyl-tetrahydrothiopyran and was used directly in the subsequent reaction.
Step E: Tetrahydro-3-propyl-(2H)-1,4-thiazepin-5-one and tetrahydro-6-propyl-(2H)-1,4-thiazepin-5-one
Employing the procedure described in Example 2, step B, 4-oximino-3-propyl-tetrahydrothiopyran was converted to a 3:1 mixture of tetrahydro-3-propyl-(2H)-1,4-thiazepin-5-one and tetrahydro-6-propyl-(2H)-1,4-thiazepin-5-one.
Step F: Tetrahydro-3-propyl-(2H)-1,4-thiazepin-5-thione
Employing the procedure described in Example 2, step C, the mixture of tetrahydro-3-propyl-(2H)-1,4-thiazepin-5-one and tetrahydro-6-propyl-(2H)-1,4-thiazepin-5-one was reacted with Lawesson's reagent to yield the corresponding thioamides. The 3-n-propyl isomer was isolated and purified by flash column chromatography on silica gel eluted with methylene chloride:hexanes (1:1) to yield tetrahydro-3-propyl-(2H)-1,4-thiazepin-5-thione as a single compound.
1 H NMR (500 MHz, CDCl 3 ): δ8.06 (brs, 1H), 3.95 (m, 1H), 3.58 (m, 1H), 3.30 (m, 1H), 2.85 (m, 1H), 2.73 (m, 2H), 2.56(m, 1H), 1,71-1.42 (m, 4H), 0.97 (t, J=7.3 Hz, 3H).
13 C NMR (125 MHZ, CDCl 3 ): δ208.08, 61.95, 48.61, 37.70, 34.41, 25.75, 19.24, 13.68.
Step G: Hexahydro-5-imino-3-propyl-1,4-thiazepine hydrochloride
Employing the procedure described in Example 2, step D, tetrahydro-3-propyl-(2H)-1,4-thiazepin-5-thione was reacted with Meerwein's salt and ammonium chloride to yield hexahydro-5-imino-3-propyl-1,4-thiazepine, hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ3.93 (m, 2H), 3.23-2.62 (m, 6H), 1.68-1.47(m, 4H), 0.98 (t, 3H, J=7 Hz).
13 C NMR (125 MHZ, CD 3 OD): δ170.96, 58.65, 36.54, 34.99, 34.10, 23.36, 18.87, 12.68. MS: m/z =173.1 (M+1).
EXAMPLE 5 ##STR14##
Hexahydro-5-imino-6-propyl-1,4-thiazepine hydrochloride
The 6-propyl thioamide isomer isolated from Example 4, Step F was reacted with Meerwein's salt and ammonium chloride according to the procedure described in Example 2, Step D to yield hexahydro-5-imino-6-propyl-1,4-thiazepine, hydrochloride.
1 H NMR (500 MHz, CD 3 OD) 3.75 (m, 2H), 3.18 (m, 1H), 2.95 (dd, 1H), 2.82 (m, 1H), 2.73 (m, 2H), 1.87 (m, 2H), 1.50 (m, 1H), 1.39 (m, 1H), 0.99 (t, 3H).
Mass spectrum: m/z=173 (M+1)
EXAMPLE 6 ##STR15##
Hexahydro-5-imino-7-methyl-1,4-thiazepine hydrochloride
Step A: 2,3-Dihydrothiopyran-4-one-3-carboxylic acid, allyl ester
To a solution of tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester (Example 4, step A) (2.3 g, 11.5 mmol) in 100 mL dry chloroform at room temperature was added activated manganese dioxide (10 g, 115 mmol) and the resulting mixture was refluxed for 5 h. The reaction mixture was filtered and evaporated. The the remaining residue was purified by flash column chromatography on silica gel eluted with hexane:ethyl acetate (7:3) to give 2,3-dihydrothiopyran-4-one-3-carboxylic acid, allyl ester (0.988 g).
1 H NMR (500 MHz, CDCl 3 ): δ8.49 (s, IH), 5.97 (m, iH), 5.41-5.25 (m, 2H), 4.70 (m, 2H), 3.29 (m, 2H), 2.82 (m, 2H).
13 C NMR (125 MHZ, CDCl 3 ): δ189.26, 162.68, 156.42, 131.97, 125.20, 118.61, 65.75, 37.83, 27.29.
Step B: 2-Methyl-tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester
To a stirring solution of methyl cuprate in dimethylsulfide (prepared from 1.05 g copper (I) iodide/4.0 mL dimethylsulfide and 4.0 mL methyllithium/ether at -78° C.) at -78° C. was added a solution of 2,3-dihydrothiopyran-4-one-3-carboxylic acid, allyl ester (0.910 g, 4.6 mmol) in dimethylsulfide (5 mL). The resulting yellow-colored solution was stirred for 30 min. at the same temperature. The reaction mixture was quenched with a saturated solution of ammonium chloride and ammonia solution and then warmed to room temperature for and 1 h. The reaction mixture was added to ether (100 mL) and the etheral layer washed with saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was evaporated and the product purified by flash column chromatography on silica gel eluted with hexane:ether (4:1) to give 2-methyl-tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester (0.794 g) as a 7:3 mixture of enol:keto tautomers.
1 H NMR (500 MHz, CDCl 3 ): δ12.67 (s, 1H), 5.94 (m, 1H), 5.35-5.27 (m, 2H), 4.70 (m, 2H), 3.09-2.50(m, 6H), 1.52 (d, J=6.9 Hz, 3H).
13 C NMR (125 MHZ, CDCl 3 ): δ173.02, 131.86, 119.50, 66.71, 65.33, 42.66, 30.76, 23.95, 20.02.
Step C: 2-Methyl-tetrahydrothiopyran-4-one
Employing the procedure described in Example 4, step C, 2-methyl-tetrahydrothiopyran-4-one-3-carboxylic acid, allyl ester was decarboxylated to form 2-methyl-tetrahydrothiopyran-4-one.
Step D: Hexahydro-5-imino-7-methyl-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, steps D through G, 2-methyl-tetrahydrothiopyran-4-one was converted to hexahydro-5-imino-7-methyl-1,4-thiazepine, hydrochloride
1 H NMR (500 MHz, D 2 O): δ3.78 (d, 1H, J=15 Hz), 3.62 (dd, 1H, J=15, 7 Hz), 3.05 (m, 2H), 2.87 (m, 2H), 2.10 (m, 1H), 1.21 (d, 3H, J=7 Hz).
13 C NMR (125 MHz, CD 3 OD): δ51.87, 36.76, 34.73, 22.12, 17.34.
Mass spectrum: m/z=145.1 (M+1).
and hexahydro-5-imino-2-methyl-1,4-thiazepine hydrochloride (see Example 7).
EXAMPLE 7 ##STR16##
Hexahydro-5-imino-2-methyl-1,4-thiazepine hydrochloride
Hexahydro-5-imino-2-methyl-1,4-thiazepine hydrochloride was prepared according to the procedures described in Example 6.
1 H NMR (500 MHz, CD 3 OD): δ3.80 (ABq, 2H), 3.30 (m, 1H), 3.12 (m, 2H), 2.80 (ABq, 2H), 1.39 (d, 3H, J=7 Hz).
13 C NMR (125 MHz, CD 3 OD) δ46.62, 42.25, 32.51, 28.01, 20.26.
Mass spectrum: m/z=145.2 (M+1).
EXAMPLE 8 ##STR17##
Hexahydro-5-imino-6-(3-methyl-2-n-butenyl)-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting 1-bromo-3-methyl-2-n-butene for 1-iodopropane in step B, the 6-positional isomer was separated from the 3-positional isomer (see Example 9) as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-6-(3-methyl-2-n-butenyl)-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ5.10 (m, 1H), 4.15, (m, 1H), 3.79 (m, 1H), 1.75 (s, 3H), 1.71 (s, 3H).
Mass spectrum: m/z=199.2 (M+1).
EXAMPLE 9 ##STR18##
Hexahydro-5-imino-3-(3-methyl-2-n-butenyl)-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting 1-bromo-3-methyl-2-n-butene for 1-iodopropane in step B, the 3-positional isomer was separated from the 6-positional isomer (see Example 8) by flash column chromatography as its respective thioamide. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-3-(3-methyl-2-n-butenyl)-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ5.17 (br t, 1H), 3.96 (ABq, 2H), 3.22 (m, 1H), 3.09 (m, 1H), 2.45 (m, 2H), 1.75 (s, 3H), 1.70 (s, 3H).
13 C NMR (125 MHZ, CD 3 OD) δ118.04, 59.14, 35.09, 33.38, 32.93, 24.63, 23.36, 16.81.
Mass spectrum: m/z=199.2 (M+1).
EXAMPLE 10 ##STR19##
Hexahydro-5-imino-6-(2-methyl-propyl)-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting isobutyl iodide for 1-iodopropane in step B, the 6-positional isomer was separated from the 3-positional isomer (see Example 11) as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-6-(2-methyl-propyl)-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ3.77 (t, 2H), 3.25 (m, 1H), 2.95 (d of d, 1H), 2.83 (m, 1H), 2.73 (m, 2H), 1.87 (m, 1H), 1.70 (m, 2H), 1.01 (d, 3H), 0.99 (d, 3H).
Mass spectrum: m/z=187.2
EXAMPLE 11 ##STR20##
Hexahydro-5-imino-3-(2-methyl-propyl)-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting isobutyl iodide for 1-iodopropane in step B, the 3-positional isomer was separated from the 6-positional isomer (see Example 10) as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-3-(2-methyl-propyl)-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ3.95 (m, 1H), 3.25 (m, 1H), 3.10 (m, 1H), 2.87 (m, 1H), 2.80 (m, 1H), 2.73 (d, 1H), 2.65 (d of d, 1H), 1.76 (m, 1H), 1.69 (m, 1H), 1.5 (m, 1H), 0.98 (t, 6H)
Mass spectrum: m/z=187.2
EXAMPLE 12 ##STR21##
Hexahydro-5-imino-6-methyl-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting methyl iodide for 1-iodopropane in step B, the 6-positional isomer was separated from the 3-positional isomer (see Example 13) as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-6-methyl-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ3.78 (t, 2H), 3.4 (m, 1H), 2.82 (m, 2H), 2.72 (m, 2H), 1.42 (d, 3H)
Mass spectrum: m/z=145.0
EXAMPLE 13 ##STR22##
Hexahydro-5-imino-3-methyl-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting methyl iodide for 1-iodopropane in step B, the 3-positional isomer was separated from the 6-positional isomer (see Example 13) as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-3-methyl-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ4.07 (m, 1H), 3.19 (m, 1H), 3.04 (m, 1H), 2.80 (m, 2H), 2.69 (m, 2H), 11.39 (d, 3H)
Mass spectrum: m/z=145.1
EXAMPLE 14 ##STR23##
Hexahydro-5-imino-3-ethyl-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting ethyl iodide for 1-iodopropane in step B, the 3-positional isomer was separated from the 6-positional isomer as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-3-ethyl-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ3.87 (m, 1H), 3.23 (m, 1H), 3.06 (m, 1H), 2.80 (m, 2H), 2.64 (d of d, 2H), 1.75 (m, 2H), 1.04 (t, 3H).
Mass spectrum: m/z=159.1
EXAMPLE 15 ##STR24##
Hexahydro-5-imino-3-butyl-1,4-thiazepine, hydrochloride
Employing the procedures described in Example 4, but substituting butyl iodide for 1-iodopropane in step B, the 3-positional isomer was separated from the 6-positional isomer as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-3-butyl-1,4-thiazepine, hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ3.90 (m, 1H), 3.23 (m, 1H), 3.02 (m, 1H), 2.80 (m, 2H), 2.63 (d of d, 1H), 1.70 (m, 3H), 1.40 (m, 4H), 0.94 (t, 3H).
Mass spectrum: m/z=187.2
EXAMPLE 16 ##STR25##
Hexahydro-5-imino-3-(2-methyl-3-propenyl)-1,4-thiazepine hydrochloride
Employing the procedures described in Example 4, but substituting 3-bromo-2-methylpropene for 1-iodopropane in step B, the 3-positional isomer was separated from the 6-positional isomer as its respective thioamide by flash column chromatography. Subsequently, reaction with Meerwein's salt and ammonium chloride as described in Example 2, step D gave hexahydro-5-imino-3-(2-methyl-3-propenyl)-1,4-thiazepine hydrochloride.
1 H NMR (500 MHz, CD 3 OD): δ4.85 (s, 1H), 4.75 (s, 1H), 4.13 (m, 1H), 3.28 (m, 1H), 3.12 (m, 1H), 2.88 (m, 1H), 2.82 (m, 1H), 2.78 (d, 1H), 2.66 (d of d, 1H), 2.45 (m, 2H), 1.78 (s, 3H).
Mass spectrum: m/z=185.1
EXAMPLE 17 ##STR26##
(±)-trans-Decahydro-4-imino-benzo[b]-1,4-thiazepine acetic acid salt
Step A: (±)-trans-2-(tert-Butoxycarbonylamino)-cyclohexanol
To a vigoursly stirring solution of trans-2-aminocyclohexanol hydrochloride (5.5 g, 36 mmol) in 100 mL methylene chloride and saturated sodium bicarbonate solution (1:1) at 0° C. was added di-tert-butylcarbonate (13.09 g, 60 mmol). The resulting heterogeneous mixture was warmed to the room temperature and stirred overnight. The methylene chloride layer was washed with brine, dried and evaporated. The solid obtained was triturated with hexane and filtered to give 5.86 g (96%) of (±)-trans-2-N-(tert-butoxycarbonyl)-cyclohexanol.
1 H NMR (500 MHz, CDCl 3 ): δ4.61(brs, 1H), 3.27 (m, 1H), 2.73 (brs, 1H), 2.02-1.69 (m, 4H), 1,45 (s, 9H), 1.42-1.09(m, 4H).
13 C NMR (125 MHz, CDCl 3 ): δ75.42, 56.62, 34.22, 31.84, 28.43, 27.48, 24.78, 24.11.
Step B: (±)-7-(tert-Butoxycarbonyl)-7-aza-bicyclo-[4.1.0]-cycloheptane
To a stirring mixture of (±)-trans-2-N-(tert-butoxycarbonyl)-cyclohexanol (4.08 g, 20 mmol) and triphenylphosphine (10.49 g, 40 mmol) in 50 mL of tetrahydrofuran at 0° C. was slowly added diisopropyl azodicarboxylate (8.08 g, 40 mmol). The reaction mixture was warmed to the room temperature and stirred until the TLC indicated the disappearence of the starting alcohol (appro. 2-4 hrs). The tetrahydrofuran was evaparated in vacuo and the crude product was passed through a silica gel column and eluted with hexane/methylene chloride (1:1) to give 3.18 g (85%) of the desired (±)-7-(tert-butoxycarbonyl)-7-aza-bicyclo-[4.1.0]-cycloheptane as an oil.
1 H NMR (500 MHz, CDCl 3 ): δ2.55 (m, 2H), 1.93-1.75 (m, 4H), 1.45 (s, 9H), 1.44-1.21(m, 4H).
13 C NMR (125 MHz, CDCl 3 ): δ80.62, 36.96, 28.04, 23.80, 19.93.
Step C: (±)-trans-2-amino-1-[2-(carboxy)ethylthio]-cyclohexane hydrochloride
(±)-7-(tert-Butoxycarbonyl)-7-aza-bicyclo-[4.1.0]-cycloheptane (0.5 g, 2.68 mmol) was dissolved in 2 mL dimethylformamide and β-mercaptopropionic acid (0.318 g, 3 mmol). After the addition of cesium carbonate (1.95 g, 6 mmol), the mixture was stirred at 60° C. until the TLC indicated the full consumption of starting material (appro. 4 hrs). The reaction mixture was diluted with water, the pH was adjusted to 4 (with 2.4 M HCl) and finally extracted with methylene chloride. The solvent layer was washed with brine, dried and evaporated to give the crude (±)-trans-2-(tert-butocycarbonylamino)-1-[2-(carboxy)ethylthio]-cyclohexane, which was not purified but taken to the next stage. The crude from the above was dissolved in 10 ml ethyl acetate saturated with hydrogen chloride and stir at room temperature. The white precipitate that resulted was filtered and dried under vacuo yielding 0.636 g of (±)-trans-2-amino-1-[2-(carboxy)ethylthio]-cyclohexane.
1 H NMR (500 MHz, D 2 O): δ3.20 (m, 1H), 2.81-2.65 (m, 3H), 2.24 (m, 2H), 1.79-1.2 (m, 8H).
Step D: (±)-trans-Decahydro-4-oxo-benzo[b]-1,4-thiazepine
To (±)-trans-2-amino-1-[2-(carboxy)ethylthio]-cyclohexane hydrochloride (0.240 g, 1 mmol) dissolved in 2 mL of dimethylformaamide at 0° C. was successively added 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (0.356 g, 1.2 mmol), 1-hydroxy-7-azabenzotriazole (0.164 g, 1.2 mmol) and then finally N-methylmorpholine (0.252 g, 2.5 mmol). After stirring for an additional 5 mins., the reaction mixture was warmed to room temperature and stir-red overnight at the same temperature. The following day the reaction mixture was diluted with water and extracted with methylene chloride. The solvent layer was washed with brine, dried and evaporated to give the crude which was purified by silica column and eluted with hexane/ethylacetate (7:3+5% methanol) to give 0.102 g (55%) of (±)-trans-decahydro-4-oxo-benzo[b]-1,4-thiazepane as white solid.
1 H NMR (500 MHz, CDCl 3 ): δ5.66 (s, 1H), 3.46 (m, 1H), 2.98-2.64 (m, 5H), 2.05-1.74 (m, 4H), 1.39-1.21 (m, 4H).
13 C NMR (125 MHz, CDCl 3 ): δ175.94, 58.07, 46.78, 40.50, 33.77, 31.70, 25.32, 24,67, 24.52.
Step E: (±)-trans-Decahydro-4-thioxo-benzo[b]-1,4-thiazepine
To a solution of (±)-trans-decahydro-4-oxo-benzo[b]-1,4-thiazepane (0.100 g, 0.54 mmol) in 5 mL of dry toluene was added Lawesson's reagent [2,4-bis(4-methoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide] (0.328 g, 0.81 mmol) and the mixture was stirred at 90° C. for 30 mins. Evaporation of the solvent in vacuo followed by purification by flash column chromatography on silica gel eluted with methylene chloride:ethyl acetate (19:1) gave 0.083 g (77%) of (±)-trans-decahydro-4-thioxo-benzo[b]-1,4-thiazepine.
1 H NMR (500 MHz, CDCl 3 ): δ7.70 (brs, 1H), 3.72 (m, 1H), 3.65 (m, 1H), 3.23 (m, 1H), 2.96 (m, 1H), 2.77-2.65 (m, 2H), 2.14-1.25 (m, 8H).
13 C NMR (125 MHZ, CDCl3): δ63.26, 48.42, 44.43, 33.73, 31.41, 26.45, 25.06, 24.31.
Step F: (±)-trans-Decahydro-4-imino-benzo[b]1,4-thiazepine acetic acid salt
To a solution of (±)-trans-decahydro-4-thioxo-benzo[b]-1,4-thiazepane (25 mg, 0.12 mmol) in 2 mL of dry methylene chloride at room temperature was added trimethyloxonium tetrafluoroborate (Meerwein's salt) (24 mg, 0.16 mmol). The resulting mixture was stirred at room temperature overnight. The reaction mixture was quenched with saturated solution of sodium bicarbonate solution and stir for 5 mins. The methylene chloride layer was washed with water, saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo to give the crude imino-ether which was subsequently treated with ammonium chloride (14 mg) in 4 mL of ethanol and heated at 80° C. for 4 h. Evaporation of ethanol followed by purification by column chromatography and elution with acetonitrile:water:acetic acid (90:5:5) gave 21.8 mg (±)-trans-decahydro-4-imino-benzo[b]-1,4-thiazepine acetic acid salt.
1 H NMR (500 MHz, D 2 O): δ3.68 (m, 1H), 3.64 (m, 1H), 3.26-2.83 (m, 4H), 2.06-1.23 (m, 8H).
13 C NMR (125 MHZ, CDCl 3 ): δ58.72, 45.32, 33.96, 31.85, 31,76, 25.00, 23.95, 21.47.
Mass spectrum: m/z=185.1 (M + )
EXAMPLE 18 ##STR27##
Hexahydro-5-imino-3(S)-propyl-1,4-thiazepine, acetic acid salt
Step A: Tetrahydro-3(S)-propyl-(2H)-1,4-thiazepine-5-thione
The title compound was prepared employing the procedure in Example 17, Steps A to E and starting from L-norvalinol instead of (±)-trans-2-aminocyclohexanol.
Step B: Hexahydro-5-imino-3(S)-propyl-1,4-thiazepine acetic acid salt
To a solution of tetrahydro-3(S)-propyl-(2H)-1,4-thiazepine-5-thione (42 mg, 0.22 mmol) in 5 mL tetrahydrofuran and saturated with ammonia gas at 60° C. was added mercuric chloride (73.3 mg, 0.27 mmol). The stream of ammonia gas was bubbled for another 10 mins. at the same temperature. After stirring for 2 h, the reaction mixture was filtered and the filtrate was evaporated. The crude compound was then purified by column chromatography and eluted with acetonitrile:water:acetic acid (90:5:5) giving 31.5 mg of hexahydro-5-imino-3(S)-propyl-1,4-thiazepine acetic acid salt.
1 H NMR (500 MHz, CD 3 OD): δ3.93 (m, 1H), 3.30-2.61 (m, 6H), 1.72-1.40 (m, 4H), 0.97 (t, 3H, J=7.3 Hz).
13 C NMR (125 MHZ, CD 3 OD): δ58.58, 36.42, 34.95, 34.09, 23.33, 18.87, 12.61.
Mass spectrum: m/z=173.1 (M+1).
EXAMPLE 19 ##STR28##
Hexahydro-5-imino-3(R)-propyl-1,4-thiazepine acetic acid salt
Step A: Tetrahydro-3(R)-propyl-(2H)-1,4-thiazepine-5-thione
The title compound was prepared employing the procedure in Example 17, Steps A-E and starting from D-norvalinol instead of (±)-trans-2-aminocyclohexanol.
Step B: Hexahydro-5-imino-3(R)-propyl-1,4-thiazepine acetic salt
Employing the procedure 19, step B, tetrahydro-3(R)-propyl-(2H)-1,4-thiazepine-5-thione (40 mg, 0.21 mmol) was converted to 37.4 mg of hexahydro-5-imino-3(R)-propyl-1,4-thiazepine acetic acid salt.
1 H NMR (500 MHz, CD 3 OD): d 3.93 (m, 1H), 3.29-3.02 (m, 2H), 2.87-2.61 (m, 4H), 1.73-1.41 (m, 4H), 0.97 (t, 3H, J=7.3 Hz). 13 C NMR (125 MHZ, CD 3 OD): d 58.60, 36.43, 34.96, 34.10, 23.35, 18.87, 12.63.
Mass spectrum: m/z=173.1 (M+1).
EXAMPLE 20 ##STR29##
Hexahydro-5-imino-1-methyl-1H-1,4-diazepine hydrochloride
Employing the method of Foloppe et al. (M. P. Foloppe, S. Rault, and M. Robba, Tetrahedron Lett. 1992, 31, 2803-2804), a solution of hexahydro-1-methyl-(5H)-1,4-diazepin-5-thione (R. Guryn, Polish J. Chem. 1987, 61, 259-262) (100 mg, 0.694 mmol) in tetrahydrofuran (5.0 mL) was warmed in a 55° C. oil bath as ammonia was bubbled into the solution. Mercuric chloride (207 mg, 0.764 mmol) was added in one portion, and the mixture quickly became black. After 20 min, the introduction of ammonia was discontinued and the mixture was stirred at room temperature for 1 h. The mixture was then centrifuged and the supernatant was decanted. The pellet was resuspended in tetrahydrofuran (3 mL), the mixture was centrifuged, and the supernatant was decanted. This was repeated with 2×3 mL of tetrahydrofuran and then 3×3 mL of methanol. The methanol extracts were combined, filtered through a 0.45 micron membrane, and evaporated to give 131 mg of white solid. Based on the combustion analysis for carbon, this material contained 92 mg (82% yield) of hexahydro-5-imino-1-methyl-(1H)-1,4-diazepine hydrochloride salt.
1 H NMR (400 MHz, CD 3 OD): δ3.56-3.52 (m, 2H), 2.88 (dd, 2H, J=6 Hz, 3 Hz), 2.79-2.71 (m, 2H), 2.71-2.63 (m, 2H), 2.43 (s, 3H).
Mass spectrum: m/z=128 (M-HCl+1). Anal. calc'd. for C 6 H 14 N 3 Cl.1.23 NH 4 Cl: C, 31.1; H, 8.40; N, 25.5; Cl, 34.1. Found: C, 31.08; H, 8.16; N, 23.41; Cl, 34.06. | Disclosed herein are compounds of Formula I and pharmaceutically acceptable salts thereof which have been found useful in the treatment of nitric oxide synthase mediated diseases and disorders, including neurodegenerative disorders, disorders of gastrointestinal motility and inflammation. These diseases and disorders include hypotension, septic shock, toxic shock syndrome, hemodialysis, IL-2 therapy such as in in cancer patients, cachexia, immunosuppression such as in transplant therapy, autoimmune and/or inflammatory indications including sunburn, eczema or psoriasis and respiratory conditions such as bronchitis, asthma, oxidant-induced lung injury and acute respiratory distress (ARDS), glomerulonephritis, restenosis, inflammatory sequelae of viral infections, myocarditis, heart failure, atherosclerosis, osteoarthritis, rheumatoid arthritis, septic arthritis, chronic or inflammatory bowel disease, ulcerative colitis, Crohn's disease, systemic lupus erythematosis (SLE), ocular conditions such as ocular hypertension, retinitis and uveitis, type 1 diabetes, insulin-dependent diabetes mellitus and cystic fibrosis. | 2 |
[0001] This is a divisional of U.S. patent application Ser. No. 09/944,664, filed on Aug. 31, 2001, which claims the benefit of the priority of U.S. Provisional Patent Application Serial No. 60/229,494, filed on Aug. 31, 2000.
BACKGROUND OF THE INVENTION
[0002] Lithium compounds are commonly used as initiators for anionic polymerizations. Such organolithium initiators can be employed in synthesizing a wide variety of rubbery polymers. For instance, organolithium initiators can be used to initiate the anionic polymerization of diolefin monomers, such as 1,3-butadiene and isoprene, into rubbery polymers. Vinyl aromatic monomers can, of course, also be copolymerized into such polymers. Some specific examples of rubbery polymers that can be synthesized using organolithium compounds as initiators include polybutadiene, polyisoprene, styrene-butadiene rubber (SBR), styrene-isoprene rubber, and styrene-isoprene-butadiene rubber (SIBR).
[0003] The organolithium compounds that can be used to initiate such anionic polymerizations can be either a specific organomonolithium compound or it can be a multifunctional type of initiator. In commercial applications monolithium compounds are normally used because they are available as pure compounds that are soluble in organic solvents. Multifunctional organolithium compounds are not necessarily specific compounds but rather represent reproducible compositions of regulable functionality. Many of such multifunctional organolithium compounds must be stored under refrigeration before being used.
[0004] U.S. Pat. No. 5,981,639 explains that multifunctional initiators used to initiate anionic polymerizations include those prepared by reacting an organomonolithium compounded with a multivinylphosphine or with a multivinylsilane, such a reaction preferably being conducted in an inert diluent such as a hydrocarbon or a mixture of a hydrocarbon and a polar organic compound. The reaction between the multivinylsilane or multivinylphosphine and the organomonolithium compound can result in a precipitate which can be solubilized if desired, by adding a solubilizing monomer such as a conjugated diene or monovinyl aromatic compound, after reaction of the primary components. Alternatively, the reaction can be conducted in the presence of a minor amount of the solubilizing monomer. The relative amounts of the organomonolithium compound and the multivinylsilane or the multivinylphosphine preferably should be in the range of about 0.33 to 4 moles of organomonolithium compound per mole of vinyl groups present in the multivinylsilane or multivinylphosphine employed.
[0005] U.S. Pat. No. 5,981,639 further notes such multifunctional initiators are commonly used as mixtures of compounds rather than as specific individual compounds. Other multifunctional polymerization initiators can be prepared by utilizing an organomonolithium compound, further together with a multivinylaromatic compound and either a conjugated diene or monovinylaromatic compound or both. These ingredients can be charged initially, usually in the presence of a hydrocarbon or a mixture of a hydrocarbon and a polar organic compound as a diluent. Alternatively, a multifunctional polymerization initiator can be prepared in a two-step process by reacting the organomonolithium compound with a conjugated diene or monovinyl aromatic compound additive and then adding the multivinyl aromatic compound. Any of the conjugated dienes or monovinyl aromatic compounds described can be employed. The ratio of conjugated diene or monovinyl aromatic compound additive employed preferably should be in the range of about 2 to 15 moles of polymerizable compound per mole of organolithium compound. The amount of multivinylaromatic compound employed preferably should be in the range of about 0.05 to 2 moles per mole of organomonolithium compound. Exemplary multivinyl aromatic compounds include 1,2-divinylbenzene, 1,3-divinylbenzene, 1,4-divinylbenzene, 1,2,4-trivinylbenzene, 1,3-divinylnaphthalene, 1,8-divinylnaphthalene, 1,3,5-trivinylnaphthalene, 2,4-divinylbiphenyl, 3,5,4′-trivinylbiphenyl, m-diisopropenyl benzene, p-diisopropenyl benzene, 1,3-divinyl-4,5,8-tributylnaphthalene and the like. Divinyl aromatic hydrocarbons containing up to 18 carbon atoms per molecule are preferred, particularly divinylbenzene as either the ortho, meta or para isomer and commercial divinylbenzene, which is a mixture of the three isomers, and other compounds, such as the ethylstyrenes, also is quite satisfactory.
[0006] U.S. Pat. No. 4,196,154 discloses organic liquid soluble multifunctional lithium containing initiators are prepared by reacting an organo lithium compound with an organic compound containing at least one group of the configuration 1,3-bis(1-phenylethenyl)benzene. U.S. Pat. No. 4,196,154 reports that such initiators can be prepared in the absence of polar solvents and are very desirable for the polymerization of dienes such as butadiene to a desirable 1,4 configuration.
SUMMARY OF THE INVENTION
[0007] This invention discloses a process for making dilithium initiators in high purity. This process can be conducted in the absence of amines which is desirable since amines can act as modifiers for anionic polymerizations. The dilithium compounds made are highly desirable because they are soluble in aromatic solvents and do not need to be stored under refrigeration.
[0008] The present invention more specifically discloses a process for synthesizing a dilithium initiator which comprises reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C.
[0009] The present invention further discloses a process for synthesizing m-di-(1-lithio-1-methyl-3,3-dimethylbutyl)benzene which comprises reacting diisopropenylbenzene with tertiary-butyllithium in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C.
[0010] The subject invention also discloses a process for synthesizing a functionalized lithium initiator which comprises the steps of (1) reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. to produce a dilithium initiator; and (2) reacting the dilithium initiator with a halide compound selected from the group consisting of (a) tin halides of the structural formula:
[0011] (b) silicon halides of the structural formula:
[0012] (c) amine halides of the structural formula:
[0013] and (d) phosphorus halides of the structural formula:
[0014] wherein X represents a halogen atom, and wherein R1, R2, and R3 can be the same or different and represent alkyl groups, aryl groups, or alkoxy groups containing from 1 to about 10 carbon atoms.
[0015] The present invention also discloses a process for synthesizing a functionalized lithium initiator which comprises the steps of (1) reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. to produce a dilithium initiator; and (2) reacting the dilithium initiator with a compound having the structural formula:
[0016] wherein X represents a neucleophile, and wherein R1, R2, and R3 can be the same or different and represent alkyl groups, aryl groups, or alkoxy groups containing from 1 to about 10 carbon atoms. The neucleophile will typically be selected from the group consisting of aldehydes, ketones, esters, halides, and acetals. Halides are typically preferred.
[0017] The present invention further discloses a process for synthesizing a functionalized lithium initiator which comprises the steps of (1) reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. to produce a dilithium initiator; and (2) reacting the dilithium initiator with a alkylaminoaryl compound of the structural formula:
[0018] wherein R, R′, and R″ can be the same or different, wherein R is selected from the group consisting of hydrogen atoms, alkyl groups, aryl groups, alkaryl groups, and amino aryl groups, and wherein R′ and R″ represent alkyl groups.
[0019] The present invention also reveals a process for synthesizing a functionalized lithium initiator which comprises reacting a dilithium initiator with an alkylaminoaryl compound of the structural formula:
[0020] wherein R, R′, and R″ can be the same or different, wherein R is selected from the group consisting of hydrogen atoms, alkyl groups, aryl groups, alkaryl groups, and amino aryl groups, and wherein R′ and R″ represent alkyl groups.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Dilithium initiators can be synthesized using the process of this invention by reacting a tertiary-alkyl lithium compound with m-diisopropenylbenzene in an aromatic solvent. The aromatic solvent will typically be an alkyl benzene. The alkyl group in the alkyl benzene will typically contain from 1 to 8 carbon atoms. It is preferred for the alkyl group in the alkyl benzene solvent to contain from 1 to about 4 carbon atoms. Some preferred aromatic solvents include toluene, ethyl benzene, and propyl benzene. Ethyl benzene is the most highly preferred aromatic solvent.
[0022] It is critical for a tertiary-alkyl lithium compound to be reacted with the m-diisopropenylbenzene. The tertiary-alkyl lithium compound will typically contain from 4 to about 8 carbon atoms. It is preferred for the tertiary-alkyl lithium compound to be tertiary-butyl lithium.
[0023] The reaction will typically be conducted at a temperature that is within the range of about 0° C. to about 100° C. It is normally preferred for the reaction between the tertiary-alkyl lithium and the m-diisopropenylbenzene to be carried out at a temperature that is within the range of about 10° C. to about 70° C. It is typically more preferred for the reaction temperature to be within the range of about 20° C. to about 40° C.
[0024] A functionalized lithium initiator can be prepared by reacting a dilithium initiator with a halide compound. Any dilithium initiator can be employed. However, dilithium initiators that are synthesized by reacting a tertiary-alkyl lithium compound with m-diisopropenylbenzene are highly preferred. The halide compound utilized will be selected from the group consisting of (a) tin halides of the structural formula:
[0025] (b) silicon halides of the structural formula:
[0026] (c) amine halides of the structural formula:
[0027] (d) phosphorus halides of the structural formula:
[0028] and (e) halides of the structural formula:
[0029] wherein X represents a halogen atom, and wherein R1, R2, and R3 can be the same or different and represent alkyl groups, aryl groups, or alkoxy groups containing from 1 to about 10 carbon atoms. R1, R2, and R3 will typically be alkyl groups containing from 1 to about 4 carbon atoms or alkoxy groups containing from 1 to 4 carbon atoms. It is preferred for R1, R2, and R3 to be methyl groups (CH3-), ethyl groups (CH3-CH2-), methoxy groups (CH3-O—), or ethoxy groups (CH3-CH2-O—).
[0030] A compound of the structural formula:
[0031] wherein X represents a neucleophile, and wherein R1, R2, and R3 can be the same or different and represent alkyl groups, aryl groups, or alkoxy groups containing from 1 to about 10 carbon atoms, can be reacted with the dilithium initiator in place of the halide compounds described above. In such compounds the neucleophile will typically be selected from the group consisting of aldehydes, ketones, esters, halides, and acetals. Halides are typically preferred neucleophiles.
[0032] The alkylaminoaryl compounds that can be reacted with the dilithium compound are typically of the structural formula:
[0033] wherein R, R′, and R″ can be the same or different, wherein R is selected from the group consisting of hydrogen atoms, alkyl groups, aryl groups, alkaryl groups, and amino aryl groups, and wherein R′ and R″ represent alkyl groups. It is typically preferred for R′ and R″ to represent alkyl groups that contain from 1 to about 8 carbon atoms. It is generally more preferred for R′ and R″ to represent alkyl groups that contain from 1 to about 4 carbon atoms, such as methyl groups, ethyl groups, propyl groups, and butyl groups. Highly preferred alkylaminoaryl compounds that can be utilized are of the structural formula:
[0034] wherein R′ and R″ can be the same or different and wherein R′ and R″ represent alkyl groups. Some highly preferred alkylaminoaryl compounds include N,N-dimethylaminobenzaldehyde and 4,4′-bis(dimethylamino)benzophenone.
[0035] The functionalization reaction will typically be carried out at a temperature that is within the range of about −80° C. to about 150° C. However, to enhance the probability of mono-functionalization, which reduces the probability of di-functionalization, the functionalization reaction will preferably be carried out at a reduced temperature. It is accordingly preferred for the functionalization reaction to be conducted at a temperature that is within the range of about −70° C. to about 20° C. It is normally more preferred for the functionalization reaction to be conducted at a temperature that is within the range of about −60° C. to about 0° C. It is also preferred for the halide compound to be added to a solution of the dilithium initiator (rather than adding the dilithium initiator to the halide compound).
[0036] The functionalized initiators made by utilizing the technique of this invention offer significant advantages when used to initiate the anionic polymerization of diene monomers, such as 1,3-butadiene or isoprene, into rubbery polymers. For instance, such functionalized initiators offer improved solubility in aliphatic solvents. More importantly, the rubbery polymers made with such functionalized initiators offer improved compatibility in rubber formulations that contain silica and/or carbon black. Such rubbery polymer can optionally be coupled with tin and/or silicon compounds. For instance, such rubbery polymers can be coupled with tin tetrachloride or silicon tetrachloride.
[0037] This invention is illustrated by the following examples that are merely for the purpose of illustration and are not to be regarded as limiting the scope of the invention or the manner in which it can be practiced. Unless specifically indicated otherwise, parts and percentages are given by weight.
EXAMPLE 1
[0038] In this example, a stable and hydrocarbon soluble dilithio initiator was prepared. Neat m-diisoproprenylbenzene (100 mmoles) was added, under nitrogen, to a dried quart (0.95 liter) bottle containing 400 ml of reagent grade ethylbenzene at room temperature. Then tert-butyllithium (in hexanes) was added in four portions of 50 mmoles with constant shaking. It was left at room temperature for two hours after the addition of the tert-butyllithium was completed. The bottle containing the reaction mixture was then rotated in a polymerization bath at 65° C. bath for two hours. After removing it from the bath, it was left to cool at room temperature. The resulting reddish brown solution containing dilithio initiator was titrated using the Gilman double titration method for active lithium. The GC-MS analysis of the hydrolyzed (with D2O) product indicated that more than 95% dilithio species was formed.
EXAMPLE 2
[0039] In this experiment, the dilithium compound synthesized by the procedure described in Example 1 was used to initiate the polymerization of 1,3-butadiene monomer into polybutadiene rubber. In the procedure used, 2300 g of a silica/amumina/molecular sieve dried premix containing 20 weight percent of 1,3-butadiene in hexanes was charged into a one-gallon (3.8 liters) reactor. Then, 19.6 ml of 0.234 M dilithio initiator (Di-Li) was added to the reactor. The target number averaged molecular weight (Mn) was 100,000.
[0040] The polymerization was carried out at 75° C. for two hours. The GC analysis of the residual monomers contained in the polymerization mixture indicated that the 100% of monomer was converted to polymer. The polymerization was then shortstopped with ethanol and the polymer cement was then removed from the reactor and stabilized with 1 phm of antioxidant. After evaporating hexanes, the resulting polymer was dried in a vacuum oven at 50° C.
[0041] The polybutadiene produced was determined to have a glass transition temperature (Tg) at −99° C. It was also determined to have a microstructure, which contained 8 percent 1,2-polybutadiene units, 92 percent 1,4-polybutadiene units. The Mooney viscosity (ML-4) at 100° C. for this polymer was also determined to be 44. It was determined by GPC to have a number average molecular weight (Mn) of 193,000 and a weight average molecular weight (Mw) of 198,000. The MWD (Mw/Mn) of this polymer was 1.03. This example clearly validated the formation of dilithio species in the Example 1 since the molecular weight of the polymer was double of the target value.
EXAMPLE 3
[0042] In this example, a telechlic functionalized polybutadiene containing 4,4′-bis(diethylamino) benzophenol functional groups on both polymer chain ends was prepared. The procedure described in Example 2 was utilized in these examples except that two molar quantity (to Di-Li) of 4,4′-bis(diethylamino) benzophenone was added to the live cement after the polymerization of 1,3-butadiene was completed. The Tg and microstructures of this functionalized PBd were identical to polymer made in Example 2. The Mooney viscosity (ML-4) at 100° C. for this polymer was 48.
EXAMPLE 4
[0043] In this example, a telechlic functionalized styrene-butadiene rubber (SBR) containing tributyl tin groups on both polymer chain ends was prepared. The procedure described in Example 2 was utilized in these examples except that a premix containing styrene/1,3-butadiene in hexanes was used as the monomers and the styrene to 1,3-butadiene ratio was 15:85. In addition, 0.75 molar ratio of TMEDA (N,N,N′,N′-tetramethylethylenediamine) to di-lithium was used as the modifier. Two molar quantities (to di-lithium) of t-butyltin chloride was added to the live cement after the polymerization of styrene/1,3-butadiene was completed. The glass transition temperature (Tg) of this functionalized SBR was determined to be −45° C. The Mooney viscosity (ML-4) at 100° C. for this polymer was determined to be 45.
EXAMPLE 5
[0044] In this example, a telechlic tin-coupled styrene-butadiene rubber (SBR) at both polymer chain ends was prepared. The procedure described in Example 4 was utilized in this example except that the target number average molecular weight (Mn) was 75,000 instead of 100,000. Tin tetrachloride was added the live cement after the polymerization of styrene/1,3-butadiene was completed. The Tg of this functionalized SBR was determined to be −45° C. The Mooney viscosity (ML-4) at 100° C. for the coupled SBR was 88 while the uncoupled base polymer (precursor prior to coupling) was 30.
EXAMPLE 6
[0045] In this experiment, 1000 grams of a silica/amumina/molecular sieve dried premix of styrene and 1,3-butadiene in hexanes containing 20 weight percent monomer was charged into a one-gallon (3.8 liter) reactor. The ratio of styrene to 1,3-butadiene was 20:80. Copolymerization was initiated by charging sodium dedecylbenzene sulfonate and the dilithium initiator made in Example 1 to the reactor at a molar ratio of 0.25:1. The copolymerization was allowed to continue at 70° C. until all of the monomer was consumed (for about one hour). Then an additional 1000 grams of monomer premix and N,N,N′,N′-tetramethylethylene-diamine (TMEDA) was charged into the reactor containing the living polymer cement. The monomer premix added contained 40% styrene and 60% 1,3-butadiene. The molar ratio of TMEDA to dilithium initiator was 5:1. The copolymerization was allowed to continue at 70° C. for an additional hour until the monomers were essentially exhausted. Then the copolymerization was shortstopped and the polymer was stabilized by the addition of an antioxidant. The SBR made was then recovered and dried in a vacuum oven. The SBR had two glass transition temperatures at −75° C. (center block) and −20° C. (outer blocks).
EXAMPLE 7
[0046] In this example, a soluble functionalized lithium initiator containing trimethyltin groups was prepared. In the procedure used, 34 ml of 1 M of trimethyltin chloride (in hexane) was added with a syringe to a quart (0.95 liter) bottle containing 200 ml of 0.34 M 1,3-bis(1-lithio-1,3,3′-trimethylbutyl) benzene (in ethyl benzene). The mixture was shaken at room temperature for about two hours. The resulting mono-lithio initiator, 1-(1-lithio-1,3,3′-trimethylbutyl)-3-(1-trimethyltin-1,3,3′-trimethylbutyl)benzene was determined by Gilman titration to be 0.13 M.
EXAMPLES 8-10
[0047] In these examples, soluble mono-lithio initiators containing tributyltin, tributylsilyl, 2-(N,N-dimethylamino)ethyl functional groups were prepared using the same procedures as described in Example 7 except that that tributyltin chloride, tributylsilicon chloride and 2-(N,N-dimethylamino) ethyl chloride were use in place of trimethyltin chloride.
EXAMPLE 11
[0048] In this experiment, a polybutadiene containing a trimethyltin functional group was prepared. In the procedure used, 2300 g of a silica/amumina/molecular sieve dried premix containing 20 weight percent of 1,3-butadiene in hexanes was charged into a one-gallon (3.8 liters) reactor. 35.3 ml of 0.13 M a mono functionalized initiator, 1-(1-lithio-1,3,3′-trimethylbutyl)-3-(1-trimethyl tin-1,3,3′-trimethylbutyl)benzene was added to the reactor. The target number averaged molecular weight (Mn) was 100,000.
[0049] The polymerization was carried out at 75° C. for 2.5 hours. The GC analysis of the residual monomers contained in the polymerization mixture indicated that the 100% of monomer was converted to polymer. The polymerization was then shortstopped with ethanol and the polymer cement was then removed from the reactor and stabilized with 1 phm of antioxidant. The polymer was then recovered by evaporation of the hexanes solvent. The resulting polymer was dried in a vacuum oven at 50° C.
[0050] The polybutadiene produced was determined to have a glass transition temperature (Tg) at −99° C. It was also determined to have a microstructure that contained 9 percent 1,2-polybutadiene units and 91 percent 1,4-polybutadiene units. The Mooney viscosity (ML-4) at 100° C. for this polymer was also determined to be 55.
EXAMPLE 12
[0051] In this example, a soluble functionalized lithium initiator containing dimethylaminophenyl was prepared. 34 ml. of 1 M p-dimethylaminobenzaldehyde (in toluene) was added, via a syringe, to a quart bottle containing 200 ml. of 0.34 M 1,3-bis(1-lithio-1,3,3-trimethylbutyl) benzene (in cyclohexane) at room temperature. The mixture was shaken at room temperature for an hour. The resulting mono-lithio initiator, 1-(1-lithio-1,3,3-trimethylbutyl)-3-(1-(p-dimethylaminophenyl, lithioxy)methyl)-1,3,3-trimethylbutyl)benzene was determined by Gilman titration to be 0.15 M.
EXAMPLE 13
[0052] In this example, a soluble mono-lithio initiators containing bis-(dimethylaminophenyl) functional groups was prepared using the same procedure as described in Example 12 except that 4,4′-bis-(dimethylamino)benzophenone (Michler's ketone) was used in place of p-dimethylamino benzaldehyde.
EXAMPLE 14
[0053] In this experiment, a 15/85 styrene-butadiene rubber (SBR) containing a 1-(4-dimthylaminophenyl)-1-hydroxymethyl functional group was prepared. 2300 g of a silica/amumina/molecular sieve dried premix containing 20 weight percent of 1,3-butadiene and styrene in hexanes was charged into a one-gallon (3.8 liters) reactor. The ratio of styrene to 1,3-butadiene was 15:85. 16.1 ml. of 0.15 M a mono functionalized initiator, 1-(1-lithio-1,3,3-trimethylbutyl)-3-(1-(p-dimethylaminophenyl, lithioxy)methyl)-1,3,3-trimethylbutyl)benzene was added to the reactor. The target number averaged molecular weight (Mn) was 200,000.
[0054] The polymerization was carried out at 70° C. for 1.5 hours. The GC analysis of the residual monomers contained in the polymerization mixture indicated that the 100% of monomer was converted to polymer. The polymerization was then shortstopped with ethanol and the polymer cement was then removed from the reactor and stabilized with 1 phm of antioxidant. After the hexanes solvent, the resulting polymer was dried in a vacuum oven at 50° C.
[0055] The SBR produced was determined to have a glass transition temperature (Tg) at −38° C. It was also determined to have a microstructure, which contained 52 percent 1,2-polybutadiene units, 33 percent 1,4-polybutadiene units and 15% random polystyrene units. The Mooney viscosity (ML-4) at 100° C. for this polymer was also determined to be 73.
[0056] While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. | This invention discloses a process for making dilithium initiators in high purity. This process can be conducted in the absence of amines which is desirable since amines can act as modifiers for anionic polymerizations. The dilithium compounds made are highly desirable because they are soluble in aromatic solvents. The present invention more specifically discloses a process for synthesizing a dilithium initiator which comprises reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. The present invention further discloses a process for synthesizing m-di-(1-lithio-1-methyl-3,3-dimethylbutyl) benzene which comprises reacting diisopropenylbenzene with tertiary-butyllithium in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. The present invention also discloses a process for synthesizing a functionalized lithium initiator which comprises reacting a dilithium initiator with an alkylaminoaryl compound of the structural formula:
wherein R, R′, and R″ can be the same or different, wherein R is selected from the group consisting of hydrogen atoms, alkyl groups, aryl groups, alkaryl groups, and amino aryl groups, and wherein R′ and R″ represent alkyl groups. | 2 |
[0001] The present invention relates to a method of locating a vehicle from satellite data. The method can be implemented in particular in the global positioning system known under the acronym “GPS”.
BACKGROUND OF THE INVENTION
[0002] Conventionally, a vehicle, such as an aircraft, is located on the basis firstly of data provided by an on-board measurement unit (e.g. including an inertial unit and a barometric altimeter), and secondly from satellite data coming from a constellation of satellites in orbit around the Earth. Combined processing of this data makes it possible to obtain a position that is accurate, referred to below as the “reference” position, and that is close to the real position of the aircraft. The accuracy of the reference position is nevertheless very sensitive to a failure in the constellation of satellites, i.e. in the event of a satellite failing in such a manner as to transmit data that is not exact, but without the failure being detected, or in the event of simultaneous or consecutive failures of two satellites in the constellation (the risk of three satellites failing simultaneously is so low that it is generally ignored).
[0003] That is why it is usual practice to provide the pilot of the aircraft with a volume known as the “protection” volume and referred to below as the overall protection volume, that is centered on reference position and that is representative of the accuracy of the reference position, taking account of the risk of one or two satellites failing. The overall protection volume is a cylinder of vertical axis defined by its radius and its height that are usually referred to as HPL and VPL. Even if the real position of the aircraft does not coincide exactly with the reference position, it nevertheless has a probability of lying outside the overall protection volume that is equal to no more than some acceptable safety threshold (or integrity risk threshold).
[0004] The protection volume corresponding to each circumstance is calculated on the basis of the statistical distribution of position error. Calculating the overall protection volume assumes that it is possible to define the integrity risk by taking account of the probabilities of no failure, of the occurrence of one failure, and of the occurrence of two failures, and to determine the overall protection volume in such a manner that the integrity risk is at least equal to the probability of that the real position lies within the overall protection volume.
[0005] In the event of no failure, determining the statistical distribution, and thus calculating the protection volume, does not raise any problem. The position error distribution function is known and it is then possible to estimate the corresponding standard deviation. This estimate is valid only on the assumption that the position has been calculated without using any erroneous data.
[0006] The event of one satellite failing is more awkward, since it is not possible to determine validly the statistical distribution of the position error on any position that is affected by a failure of a satellite, however it is possible to escape from this difficulty by calculating as many secondary positions as there are satellites and by excluding from the calculation of each of the secondary positions, data provided by a respective one of the satellites so that at least one of the secondary positions is not affected by the failure of a satellite. The secondary position and the corresponding secondary protection volume giving the greatest overall protection volume is then retained.
[0007] The circumstance of two satellites failing requires considerable computation power and is generally ignored, on the view that the probability of it occurring is too low to justify taking it into account.
[0008] Document US-A-2004/239560 describes such a method of calculating the overall protection volume.
[0009] Attempts have also been made to find means that enable the two-failure circumstance to be made negligible. It is thus known to make use of an algorithm for detecting and isolating failures, thereby minimizing the risk that a simultaneous failure of two satellites goes undetected, and thus making it possible to ignore the possibility of simultaneous failure when calculating the protection volume. Nevertheless, such an algorithm requires a large amount of computation power on board the aircraft and lengthens the time taken to process the data. In addition, the method requires appropriate validation methodology that is difficult to put into place insofar as the performance of the algorithm for detecting and isolating failures has a direct bearing on the safety (or integrity) of the airplane, given that a failure that is not detected jeopardizes the safety of the aircraft.
OBJECT OF THE INVENTION
[0010] It would therefore be advantageous to have means enabling the protection volume to be calculated in a manner that is reliable, while limiting the computer resources needed for performing the calculation and the validation efforts that are required.
SUMMARY OF THE INVENTION
[0011] To this end, the invention provides a method of locating a moving element by determining a reference position and at least one overall protection limit from data from a group of satellites in a constellation of satellites, the overall protection limit calculation comprising the step of calculating protection limits as a function of probabilities for the absence of failure in the constellation of satellites, and of failure in the constellation of satellites, the method comprising the steps of:
from the group of satellites, selecting a subgroup comprising at least five satellites; calculating a main position from the data from a group of satellites; calculating secondary positions from the data from a subgroup of satellites by excluding date from one of the satellites when calculating each secondary position; calculating protection limits corresponding to the main and secondary positions while distinguishing whether the failure in the constellation does or does not affect the satellites taken into consideration; and calculating the overall protection limit from the reference position, the main position, the secondary positions, and the protection limits corresponding to the main and secondary positions.
[0017] By selecting a subgroup from the group of satellite data items, it is possible to simplify and optimize the calculations by introducing the possibility of selecting satellites to make up the subgroup.
[0018] According to a first advantageous characteristic:
for each failure of a data-supplying satellite of the group but not of the subgroup, the corresponding protection limit is calculated on one of the secondary positions; for failure of one data-supplying satellite of the subgroup, a corresponding protection limit is calculated on each secondary position; for failure of two data-providing satellites of the group but not of the subgroup, the protection limit is calculated on one of the secondary positions; and for failure of a data-supplying satellite of the group but not of the subgroup, and of a data-supplying satellite of the subgroup, a corresponding protection limit is calculated on each secondary position; whereby failure of two data-supplying satellites of the subgroup is made negligible.
[0024] The possibility of two satellites failing is taken into account and is made negligible on the assumption of two satellites failing that supply data to the subgroup.
[0025] According to a second advantageous characteristic, the method comprises the steps of calculating an additional secondary position from the subgroup of satellite,
for failure of a data-supplying satellite of the group but not of the subgroup, the corresponding protection limit is calculated on the additional secondary position; and for failure of two data-supplying satellites of the group but not of the subgroup, the protection limit is calculated on the additional secondary position.
[0028] According to a third advantageous characteristic, the horizontal and vertical protection limits are calculated, the method comprising steps of selecting two different subgroups for calculating the horizontal and vertical protection limits.
[0029] It is thus possible to elect the satellite data best adapted to calculating the vertical protection limit and the horizontal protection limit as a function in particular of the height of the satellites and their mutual spacings.
[0030] Other characteristics and advantages of the invention appear on reading the following description of a particular, non-limiting implementation of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Reference is made to the accompanying drawings, in which:
[0032] FIG. 1 is a diagrammatic representation of a constellation of satellites present above the horizon of an aircraft; and
[0033] FIG. 2 is a diagrammatic view showing the positions and the protection limits calculated for locating the aircraft.
DETAILED DESCRIPTION OF THE INVENTION
[0034] With reference to the figures, the method of the invention is described below for an aircraft 1 having an on-board navigation system using data coming from N satellites 2 .i (where i varies over the range 1 to N, i.e. 2 . 1 , 2 . 2 , 2 . 3 , 2 . 4 , 2 . 5 , 2 . 6 , 2 . 7 , 2 . 8 , 2 . 9 , 2 . 10 , 2 . 11 , in FIG. 1 ), the satellites orbiting around the Earth 100 , and also from data coming an inertial unit on board the aircraft 1 .
[0035] The inertial unit is itself known and responds to sensors secured to the aircraft 1 to deliver data relating in particular to the attitude of the aircraft 1 , its speed,.
[0036] The satellites 2 . 1 to 2 . 11 form part of a set of satellites that are in orbit around the Earth and that belong to a satellite navigation system of the GPS type. Each satellite 2 .i continuously transmits a signal giving its location and the exact time at which the signal was transmitted. The N satellites 2 .i thus transmit N signals at regular intervals, the signals being referred to be below as satellite data.
[0037] In known manner, the navigation system comprises a calculation unit connected to an inertial navigation unit and to a receiver for receiving the signals from the satellites. In conventional manner, the calculation unit incorporates processors and memories enabling it to calculate a pseudorange separating the aircraft 1 from each satellite 2 .i from which a signal has been received by the receiver, and for merging the pseudoranges and data coming from the inertial navigation unit in order to determine, amongst other things, a position for the aircraft 1 .
[0038] The merging is performed in a manner that is itself known by using Kalman filters or any other algorithm enabling data to be merged.
[0039] The navigation system thus uses a reference filter to provide an accurate position X A or reference position on the basis of inertial data and of satellite data. The precise position X A is defined for a horizontal component (here a latitude and a longitude) and a vertical component (here an altitude).
[0040] The system also provides an overall protection volume defined by an overall horizontal protection limit HPL and an overall vertical protection limit VPL calculated from the satellite data.
[0041] The overall protection volume must be as small as possible and it is determined so that if the real position X of the aircraft does not coincide exactly with its calculated position, then the real position has a probability of lying outside the overall protection volume that is at most equal to some acceptable safety threshold. The operations for calculating the overall horizontal protection limit are specified below. The operations for calculating the overall vertical protection limit are similar.
[0042] The protection limits are calculated in a manner that is itself known on the basis of the statistical distribution of the error on the calculated position (Gaussian distribution for the vertical component of the position, and χ 2 distribution for the horizontal component of the position).
[0043] By way of example, for the horizontal protection limit HPL, the following can be written:
[0000] P(He≧HPL)≦P ir
[0000] where He is the horizontal position error and P ir is the acceptable safety threshold, also referred to as the integrity risk. This integrity risk must not be exceeded even in the event of one or two of the satellites of the constellation breaking down. The probability of three satellites of the constellation breaking down is 10 −12 , and is ignored. By way of example, for the horizontal protection limit HPL, the following applies:
[0000] (He≧HPL)= P (He≧HPL, 0 failure)× P (0 failure)+ P (He≧HPL, 1 failure)× P (1 failure)+
[0000] P (He≧HPL, 2 failures)× P (2 failures) (1)
[0044] By way of explanation, P(He≧HPL, 0 failure) means “the probability that He is greater than or equal to HPL in the absence of failure”, and P(1 failure) means “probability of one failure occurring”.
[0045] The integrity risk is likewise resolved as a function of these various cases:
[0000]
P
ir
=K
1
P
ir
+K
2
P
ir
+K
3
P
ir
[0000] where the coefficients K 1 , K 2 , and K 3 correspond respectively to the cases of no failure, the presence of one failure, and the presence of two failures.
[0046] It is not possible to determine a protection limit validly in the event of the position in question being calculated on the basis of erroneous data from at least one satellite. It is then necessary to return to a position for which the calculation does not suffer from any error.
[0047] In order to determine the overall protection volume, the system also uses a main filter to calculate a main position X 0 that is said to be reliable on the basis of the data from N satellites.
[0048] In the invention, provision is also made for the system to select data from a subgroup of n satellites taken from the group of N satellites in order to calculate, by means of a secondary filter, a secondary position X 00 or “first secondary position” The data from the n satellites is selected as a function of its pertinence for determining the horizontal component of the position (data coming from satellites that are the furthest apart is thus retained) or for determining the vertical component of the position (data coming from the highest satellites is then retained). By way of example, the pertinence of the satellites is determined by the direction cosine method, by calculating the dilution of precision (DOP) for the n possible constellations of n−1 satellites, and by conserving the satellites that come from constellations having the smallest DOP.
[0049] Provision is then made to use n−1 secondary filters to calculate n−1 additional secondary positions or “second secondary positions” X 0i (for i varying from 1 to n) while excluding the data from satellite 2 .i in order to calculate each secondary position.
[0050] Protection limits are then calculated on the assumption that there is no satellite failure, on the assumption that there is one satellite failure, and on the assumption that there are two satellite failures.
[0051] By way of example, in the description below, the horizontal protection HPL is calculated.
[0052] When there is no satellite failure, all of the satellite data is good. The protection limit is calculated on the main position X 0 calculated using data from the N satellites. The probability that none of the data is affected by a failure is (1−N)×10 −5 per hour.
[0053] Consequently the following applies:
[0000]
P
(
He
≥
HPL
,
0
failure
)
×
(
1
-
N
)
×
10
-
5
≥
K
1
P
ir
I
.
e
.
P
(
He
≥
HPL
,
0
failure
)
=
K
1
P
ir
(
1
-
N
)
×
10
-
5
(
2
)
[0054] When one satellite has failed in the group of N satellites, it is necessary to distinguish two possibilities, depending on whether:
the failing satellite belongs to the subgroup, in which case the protection limit is determined on each secondary position X 0i (one of which is good since it is calculated without making use of data from the failing satellite); or the failing satellite does not belong to the subgroup, in which case the protection limit is determined on the secondary position X 00 for which calculation is affected by the failure (whereas the position X 0 is likely to be wrong).
[0057] Under such circumstances:
[0000] K 2 P ir = P (He≧HPL, 1 failure in n)× P (1 failure in n)+ P (He≧HPL, 1 failure not in n)× P (1 failure not in n) (3)
[0058] It is decided to spread the integrity risk in equally probable manner between the two possibilities.
[0059] This gives:
[0000]
P
(
He
≥
HPL
,
1
failure
in
n
_
)
=
k
2
P
ir
2
n
×
10
-
5
(
4
)
P
(
He
≥
HPL
,
1
failure
in
n
_
)
=
k
2
P
ir
2
(
N
-
n
)
×
10
-
5
(
5
)
[0060] When two satellites fail, it is necessary to distinguish three possibilities depending on whether:
the failing satellites belong to the subgroup, in which case all of the calculated positions are wrong; one of the failing satellites belongs to the subgroup and the other does not belong thereto, in which case the protection limit is determined on each secondary position X 0i (one of which was calculated without making use of data from a failing satellite); or the failing satellites do not belong to the subgroup, in which case the protection limit is determined on the secondary position X 00 for which the calculation has not been affected by a failure (whereas the primary position X 0 is likely to be wrong).
[0064] The probability of two breakdowns affecting data from satellites during a mission of T hours is T×N 2 ×10 −10 .
[0065] This gives:
[0000] K 3 P ir =P (He≧HPL, 2 failures in n)× P (2 failures in n)+ P (He≧HPL, 1 failure in n and 1 not in n)× P (1 failure in n)× P (1 failure not in n)+ P (He≧HPL, 2 failures not in n)×
[0000] P (2 failures not in n) (6)
[0066] The portion of equation (6) concerned by the first possibility is:
[0000] P (He≧HPL for 2 failures in n)× P (2 failures in n) where
[0000] P (2 failures in n)= T×n 2 ×10 −10 . (7)
[0067] Since the protection limit cannot be calculated under such circumstances, given that all of the positions are wrong, it is decided to give the value 1 to the probability that position error is greater than the protection limit when two data-supplying satellites in the subgroup have failed. This circumstance is therefore not ignored, but on the contrary taken into account by giving it the most unfavorable probability.
[0068] Equation (6) then becomes:
[0000] K 3 P ir −T×n 2 ×10 −10 =P (He≧HPL, 1 failure in n and 1 failure not in n)× P (1 failure in n)× P (1 failure not in n)+ P (He≧HPL, 2 failures not in n)×
[0000] P (2 failures not in n) (8)
[0069] It is decided to spread the remaining integrity risk, i.e. K 3 P IR −T×n 2 ×10 −10 in equiprobable manner between the second and third possibilities.
[0070] Thus for the second possibility:
[0000]
K
3
P
ir
-
Tn
2
×
10
-
10
2
=
(
9
)
[0071] P(He≧HPL, 1 failure in n and 1 failure not in n) ×P(1 failure in n)×P(1 failure not in n) with the product of P(1 failure in n) and P(1 failure not in n) being equal to T×10 −10 ×n(N−n) giving:
[0000] P (He≧HPL, 1 failure in n and 1 failure not in n) (10)
[0000]
=
K
3
P
ir
-
Tn
2
×
10
-
10
2
T
×
10
-
10
×
n
(
N
-
n
)
[0072] For the third possibility, the following applies:
[0000]
K
3
P
ir
-
Tn
2
×
10
-
10
2
=
(
11
)
[0073] P(He≧HPL, 2 failures not in n)×P(2 failures not in n)where P(2 failures not in n)=T×10 −10 (N−n) 2 giving:
[0000]
P
(
He
≥
HPL
,
2
failures
not
in
n
_
)
=
K
3
P
ir
-
Tn
2
×
10
-
10
2
T
×
10
-
10
×
n
(
N
-
n
)
2
(
12
)
[0074] The horizontal protection limit calculated on the horizontal component of the position P 0 is referred to as HPL 0 .
[0075] The horizontal protection limit HPL 0 is determined so that:
[0000] P (He≧HPL 0 )= K 1 P ir (13)
[0076] The horizontal protection limit calculated on the horizontal component of the position P 00 is referred to as HPL 00 . The formulae (5) and (12) gives different values for the integrity risk on the position P 00 . To protect this position, it suffices to calculate a single horizontal protection limit HPL 00 corresponding to the smaller integrity risk calculated by the formulae (5) and (12). In practice, the coefficients K 1 and K 2 are calculated to obtain optimum values (i.e. values that are as close together as possible) from the formulae (5) and (12) and also (4) and (10). Other adjustment criteria could naturally be envisaged.
[0077] The horizontal protection limit HPL 00 is determined from formulae (5) and (12) in such a manner that:
[0000]
P
(
He
≥
HPL
00
)
=
min
(
K
2
P
ir
2
(
N
-
n
)
×
10
-
5
;
K
3
P
ir
-
Tn
2
×
10
-
10
2
T
×
10
-
10
×
n
(
N
-
n
)
2
)
(
14
)
[0078] The horizontal protection limit HPL 00 as calculated in this way on P 00 is then brought back to the position P 0 by calculating:
[0000] HPL 00 =HPL 00 +distance ( P 0 ,P 00 ) (15)
[0079] The horizontal protection limit calculated on the horizontal component of each position P 0i is written HPL 0i .
[0080] The horizontal protection limits HPL 0i are determined from formulae (4) and (10) in such a manner that:
[0000]
P
(
He
≥
HPL
0
i
)
=
min
(
K
2
P
ir
2
n
×
10
-
5
;
K
3
P
ir
-
Tn
2
×
10
-
10
2
T
×
10
-
10
×
n
(
N
-
n
)
)
(
16
)
[0081] The horizontal protection limits HPL 0i as calculated in this way on P 00 are then brought back to the position P 0 by calculating:
[0000] HPL 0i =HPL 0i +distance ( P 0 ,P 0i ) (17)
[0082] The overall horizontal protection limit HPL is then calculated by looking for the greatest previously-calculated protection limit, i.e.: (18) HPL=MAX{HPL 0 ,HPL 00 ,HPL 0i }
[0000] for i varying over the range 1 to N.
[0083] The method of calculation is identical for the vertical protection limit VPL.
[0084] The following is given by way of numerical example:
P ir =9×10 −8 /hour; K 1 P ir =4.12×10 −8 /hour; K 2 P ir =1.9999×10 −8 /hour; K 3 P ir =2.88065×10 −8 /hour; N=10; n=6 (the satellites retained for calculating HPL are constituted, for example by 2 . 2 , 2 . 3 , 2 . 5 , 2 . 6 , 2 . 7 , and 2 . 8 ; while the satellites retained for calculating VPL are for example 2 . 4 , 2 . 5 , 2 . 7 , 2 . 8 , 2 . 9 , and 2 . 11 ); and T=8.
[0092] Equation (12) gives P(He≧HPL 0 )=4.12×10 −8 .
[0093] Equation (14) gives P(He≧HPL 00 )=2.499×10 −4 .
[0094] Equation (16) gives P(He≧HPL 0i )=1.666×10 −4 .
[0095] Naturally, the invention is not limited to the embodiment described but covers any variant coming within the ambit of the invention as defined by the claims.
[0096] In particular, although the protection limits are brought back onto the main position P 0 , it is possible to bring the protection limits back to the precise position X A by taking account of the distance (P 0 , X A ). When the system incorporates data other than satellite data, the precise or reference position is the main position.
[0097] Naturally, the invention is equally suitable for use with other satellite navigation systems such as the GALILEO system once it comes into operation.
[0098] It is also possible to envisage not calculating the secondary position P 00 nor the associated protection limits. The configurations of satellite breakdowns normally covered by calculating protection limits on said position are then processed by calculating protection limits on the second secondary positions. | A method of locating a moving element by determining a reference position and at least one overall protection limit on the basis of data from a group of satellites in a constellation of satellites. The method comprises the steps of selecting from the group of satellites a subgroup comprising at least five satellites, calculating positions from the data from the group and from the data from the subgroup, and calculating corresponding protection limits while distinguishing whether the failure in the constellation does or does not affect the satellites under consideration. | 6 |
This application claims the benefit of Korean Application No. P2003-079414, filed on Nov. 11, 2003, and No. P2003-089508, filed on Dec. 10, 2003, which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a dryer accessory, and more particularly, to a dryer rack used in a dryer or washing machine equipped with a drying function.
2. Discussion of the Related Art
Generally, a dryer or washing machine equipped with a drying function is an apparatus for drying objects such as a laundry and the like held in a drum by supplying hot air to the drum. And, a demand for such an apparatus is gradually raised lately.
A lifter is provided within the dryer or washing machine to enhance drying performance in general. The lifter and drum are individually manufactured, and the lifter is then installed on an inside of the drum via a locking member such as a screw and the like. Instead, a lifter can be proved by ‘pressing’ in a manner that a circumferential surface of a drum is pressed to protrude from an inside of the drum. In drying an object to be dried, the corresponding object held within a drum is lifted by a plurality of lifter protruding inward from an inside of a drum up to a predetermined height and then falls. The object is easily exposed to hot air supplied to the drum to be evenly dried, thereby enhancing drying efficiency. Thus, if using the dryer or washing machine equipped with the drying function, such a relatively light drying object as cloths and the like can be conveniently dried.
However, it is difficult to dry a relatively heavy drying object using a general dryer or washing machine equipped with the drying function. Since the heavy drying object lifted by the lifters gives a considerable shock to the drum when falling, loud noise is generated from the drum or the corresponding dryer or washing machine may be out of order.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a dryer rack that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention, which as been devised to solve the foregoing problem, lies in providing a dryer rack, by which a relatively heavy drying object can be easily and safely dried.
Another object of the present invention is to provide a dryer rack, which can be easily attached to a drum of a dryer/washer to use.
A further object of the present invention is to provide a dryer rack, which can be stably and firmly loaded in a drum of a dryer/washer to use.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent to those having ordinary skill in the art upon examination of the following or may be learned from a practice of the invention. The objectives and other advantages of the invention will be realized and attained by the subject matter particularly pointed out in the specification and claims hereof as well as in the appended drawings.
To achieve these objects and other advantages in accordance with the present invention, as embodied and broadly described herein, there is provided a dryer rack for use with an apparatus for drying an object inside a drum, wherein the dryer rack includes a platform having an upper surface for supporting the object. The platform may include at least one grip for loading and unloading the dryer rack into a interior space of the drum. The at least one grip is flush with the upper surface of the platform. The at least one grip is formed in a forward portion of the platform, to be near an access point of the drum.
The at least one grip may include an opposing pair of openings formed in the platform, and a gripping surface formed on inner side surfaces on each opening. The gripping surface may be textured to facilitate gripping. And, the gripping surface may include a set of curved recesses corresponding to digits of a human hand. The gripping surfaces of the opposing pair of openings may be symmetrically arranged with respect to a centrally disposed handle.
The gripping surfaces of the opposing pair of openings are asymmetrically arranged with respect to a centrally disposed handle. Herein, the asymmetrical arrangement of the gripping surfaces provides for a thumb and four fingers, respectfully. The platform may include a pair of grips, symmetrically arranged about a central axis of the platform, for loading and unloading the dryer rack into an interior space of the drum. The pair of grips may be flushed with the upper surface of the platform. The pair of grips may also be formed in a forward portion of the platform, to be near an access point of the drum. And, the grips may be arranged at opposing angles for facilitating a two-handed grip when loading and unloading the dryer rack. Herein, the opposing angles may be between 10° and 20°.
The platform may include a tray, forming the upper surface between a forward end and a rearward end of the tray, a front support, connected to the forward end of the tray, to be supported by a first structure, and a rear support, connected to the rearward end of the tray, to be supported by a second structure, wherein the first and second structures respectively provide rotatable support to opposite ends of the drum. Herein, the plat form may include at least one grip for loading and unloading the dryer rack into an interior space of the drum. And, the at least grip may be flushed with the upper surface of the platform.
The front and rear supports may have lower surfaces for seating the dryer rack on the first and second structures. Herein, the lower surfaces of front and rear supports may be shaped to avoid interference with the drum if the drum is rotated while the dryer rack is loaded into an interior space of the drum. The platform may have a lattice structure.
In another aspect of the present invention, there if provided a dryer rack for use with an apparatus for drying an object inside a drum, wherein the dryer rack includes a tray having an upper surface for supporting the object between a forward end and a rearward end of the tray, a front support, connected to the forward end of the tray, having a first lower surface for receiving a first structure, and a rear support, connected to the rearward end of the tray, having a second lower surface for receiving a second structure, wherein the first and second structures respectively provide rotatable support to opposite ends of the drum.
The front support may rest atop a filter, installed forward of the drum, for filtering air expelled from the drum. The front support may include a pair of side extensions, connected to the forward end of the tray, for supporting the dryer rack on the filter, and an arch, stretching between the side extensions and extending downward, for being seated on an upper surface of the filter having a centrally formed recess, the arch having an arch projection for insertion into the recess of the filter.
The side extensions may be disposed forward of the tray. The rear support may include at least one leg, connected to the rearward end of the tray, for supporting the dryer rack on the second structure. The second structure may be a semicircle. Herein, the at least one leg has a curved lower surface for being seated on the semicircle of the second structure. And, the rear support may include at least two legs, connected to the rearward end of the tray, for supporting the dryer rack on the second structure, the at least two legs having opposingly curved surfaces for being respectively seated on a semicircle of the second structure.
The dryer rack may include at least one grip, formed in the upper surface of the tray, for loading and unloading the dryer rack into an interior space of the drum. The at least one grip may include an opposing pair of openings formed in the platform, and a gripping surface formed on inner sides surfaces on each opening. Herein, the griping surface may be textured to facilitate gripping. The gripping surface may include a set of curved recesses corresponding to digits of a human hand. The gripping surfaces of the opposing pair of openings may be symmetrically arranged with respect to a centrally disposed handle. Also, the gripping surfaces of the opposing pair of openings may be asymmetrically arranged with respect to a centrally disposed handle. The asymmetrical arrangement of the gripping surfaces provides for a thumb and four fingers, respectively.
In a further aspect of the present invention, there is provided a dryer rack for use with an apparatus for drying an object inside a drum, wherein the dryer rack includes a platform having an upper surface for supporting the object between a forward end and a rearward end of the tray, the upper surface having a lattice structure, a front support, connected to the forward end of the platform, having a first lower surface for receiving a first structure providing rotatable support to the drum, and at least one leg, connected to the rearward end of the platform, having a second lower structure for receiving a second structure providing rotatable support to the drum, and at least one handle provided with an opposing pair of openings formed in the platform, each opening having a gripping surface formed on an inner side surface, wherein the at least one handle is flush with the upper surface of the platform.
It is to be understood that both the foregoing explanation and the following detailed description of the present invention are exemplary and illustrative and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:
FIG. 1 is a cross-sectional diagram of an exhaust type dryer;
FIG. 2 is a perspective diagram of a dryer rack according to one embodiment of the present invention;
FIG. 3 is a perspective diagram of a dryer rack according to another embodiment of the present invention;
FIG. 4 is a perspective diagram of a front part of a dryer rack provided to a dryer according to the present invention; and
FIG. 5 is a perspective diagram of a rear part of a dryer rack provided to a dryer according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Throughout the drawings, like elements are indicated using the same or similar reference designations where possible.
First of all, a dryer rack according to the present invention can be installed in an exhaust type dryer, condensing type dryer, washer/dryer, or the like to use. In the exhaust type dryer, external air is heated to be supplied to a drum and humid air having dried a drying object within the drum is discharged outside. In the condensing type dryer, air, which is humid after having dried a drying object within a drum, is condensed by a condenser to lower humidity thereof and is then heated to be re-supplied to the drum. For convenience of explanation, a dryer rack according to the present invention installed in the exhaust type dryer is explained in the following description for example.
Referring to FIG. 1 , a drum 20 is rotatably provided within a cabinet 10 of a dryer. The drum 20 has a cylindrical shape, and a plurality of lifters 25 protrude from an inside of the drum 20 . The lifter 25 and the drum 20 are separately manufactured. Hence, the lifter 25 is attached to the inside of the drum 20 later. Instead, the lifters 25 may be built in one body of the drum 20 . A front panel 21 and rear panel 23 are mounted on an open front side and open rear side of the drum 20 to rotatably support, respectively so that the drum 20 supported by the front and rear panels 21 and 23 can be rotated in operating the dryer. While the dryer is operated, the drum is rotated but the front and rear panels 21 and 23 are not rotated.
An opening 21 a is provided to the front panel 21 , and a door 15 is installed on the front side of the cabinet 10 to open/close the opening 21 a . An exhaust duct 30 is connected to the front panel 21 . Hence, an inside of the drum 20 , as shown in FIG. 1 , enables to communicate with an external environment outside the cabinet 10 via the exhaust due 30 . Within the exhaust duct 30 , a fan 40 blowing air in the drum 20 outside and a filter 35 filtering the air discharged outside by the fan 40 are provided. The fan 40 , as shown in FIG. 1 , is rotated by a motor 50 provided within the cabinet 10 .
Meanwhile, the motor 50 may be provided to rotate the fan 40 only. Yet, in the drawing, the motor 50 is provided to rotate both of the fan 40 and the drum 20 . For this, the motor 50 includes a pair of shafts connected to the fan 40 and a pulley 60 , respectively. And, the pulley 60 , is connected to the drum 20 via a belt 65 . An air inlet duct 70 is connected to the rear panel 23 to enable the inside of the drum 20 to communicate with an external environment. As the fan 40 rotates to discharge the air within the drum 20 outside via the exhaust duct 30 , external air is supplied into the drum 20 via the air inlet duct 70 . Meanwhile, a heater 80 , as shown in FIG. 1 , is installed in the air inlet duct 70 to supply hot air into the drum 20 .
Meanwhile, a dryer rack 100 according to the present invention is detachable installed in the drum 20 of the above-constructed dryer. The dryer rack 100 can be conveniently used in drying relatively heavy objects. The dryer rack 100 according to the present invention is explained in detail by referring to FIG. 2 and FIG. 3 as follows.
Referring to FIG. 2 and FIG. 3 , a platform is provided to the dryer rack 100 to be detachably loaded in the drum 20 and to support a drying object thereon. A tray 110 having the drying object put thereon, a front support 120 extending from a front side of the tray 110 , and a rear support 130 extending from a rear side of the tray 110 are provided to the body. The tray 110 may be constructed with a perforated panel so that air can pass through the platform or have lattice shape shown in FIG. 2 . Hence, hot air supplied into the drum 20 can be smoothly provided to the drying object put on the tray 110 , whereby drying efficiency is enhanced.
The front support 120 is supported by a structure fixed to an inner front side of the dryer or washer such as the front panel 21 . And, the rear support 130 is supported by a structure fixed to an inner rear side of the dryer or washer such as the rear panel 23 . Hence, when the dryer rack 100 is loaded in the drum 20 , the tray 110 enables to maintain its position by the front and rear supports 120 and 130 without rotating within the drum 20 . In loading the dryer rack 100 in or unloading out of the drum 20 , the body, e.g., right and left sides of the tray 110 , should be taken. Hence, the loading and unloading works are inconveniently performed.
Moreover, a size of the body, and more particularly, a right-to-left width of the tray 110 , should be much smaller than a diameter of the opening 21 a . If the right-to-left width of the tray 110 is too long, it is inconvenient for a user to install or uninstall the dryer rack 100 . Besides, the user may be hurt by the opening 21 a . Hence, at least one grip 150 is provided to the dryer rack 100 according to the present invention to overcome such a problem. The at least one grip 150 is provided to the body, and more particularly, to the tray 110 so that a user can conveniently hold it to load/unload the dryer rack 100 in/from the drum 20 . The grip 150 is explained in detail by referring to FIG. 2 and FIG. 3 as follows.
Referring to FIG. 2 and FIG. 3 , the at least one grip 150 if formed at the body, and more particularly, on such a plane as the tray 110 . And, the at least one grip 150 includes a plurality of openings 151 and a grip 155 . Specifically, a pair of openings 151 , as shown in FIG. 2 and FIG. 3 , are provided to the body, and more particularly, to the tray 110 to neighbor each other. And, the grip 155 lies on a boundary of the two neighboring openings 151 to be built in one body of the tray 110 . Thus, if the grip 150 is provided to the tray 110 , a user inserts his fingers in the openings 151 to grab the corresponding grip 155 . The user then lifts the dryer rack 100 to install/uninstall in/from the drum 20 .
Meanwhile, the grip 155 preferably includes a structure enabling user's fingers to closely adhere thereto. For this, outsides of the grip 155 are formed uneven or a multitude recesses 155 a are formed on both lateral outsides of the grip 155 . A pair of the openings 151 having user's fingers inserted therein may be symmetric or identical to each other in shape. Yet, the present invention does not put limitation of the shapes of the openings 151 that can be variously modified. For instance, when a user grabs the corresponding grip 155 , user's thumb is inserted in one of the two neighbor openings 151 and the rest user's fingers are inserted in the other opening 151 . Hence, a pair of the neighbor openings 151 can be differently shaped to be fit for the thumb and the reset fingers of the user, respectfully.
Meanwhile, in order to facilitate to install the dryer rack 100 in the drum 20 , the grip 150 , as shown in FIG. 2 and FIG. 3 , is provided to a front part of the body, and more particularly, of the tray 110 . Moreover, in order to facilitate a user to grab the grip 150 using both hands, a pair of the grips 155 are symmetrically provided to the front part of the tray 110 . Furthermore, in order to facilitate a user to grab the grip 150 conveniently, the grip 155 , as shown in FIG. 2 , is tilted against a central axis in a length direction of the body, and more particularly, of the tray 110 . In this case, the grip 155 , as shown in FIG. 2 , is tilted in a manner of extending from its rear part to its front part to get farther from the central axis. And, the corresponding tilted angle is about 10°˜20°, and more preferably, about 15°.
Once the above-constructed grip is provided to the dryer rack 100 , a user grabs the grip(s) 155 of the grip(s) 150 to load the dryer rack 100 in the drum 20 with ease. When the dryer rack 100 is loaded in the drum 20 , the front and rear supports 120 and 130 are supported by immovable structures within the cabinet 10 . Yet, in a drying operation, the drum 20 keeps rotating to generate vibration. Hence, the dryer rack 100 may fall down if failing to be securely loaded therein. Hence, the front and rear supports 120 and 130 include the structures for stable loading, respectively, which are explained in detail by referring to FIGS. 2 to 5 as follows.
First of all, the front support 120 can closely adhere to the front panel 21 in direct to be supported or to a topside of the filter 35 in FIG. 1 provided to the front side of the drum 20 for filter air discharged from the drum 20 . Generally installed on the front panel 21 , the filter 35 can be regarded as a part of the front panel 21 . A curved portion 123 , a projected portion 121 , and a pair of end portions 125 are provided to the front support 120 . For example, the curved portion 123 , as shown in FIG. 2 and FIG. 3 , is convex downward. And, the curved portion 123 , as shown in FIG. 4 , closely adheres to the topside of the filter 35 . And, the projected portion 121 , as shown in FIG. 2 and FIG. 3 , is projected downward from a middle part of the curved portion 123 . The projected portion 121 , as shown in FIG. 4 , is fitted in a recess 35 a formed in the middle of the filter 35 .
Moreover, a pair of the end portions 125 , as shown in FIG. 2 and FIG. 3 , are provided to both side ends of the curved portion 123 . And, a pair of the end portions 125 , as shown in FIG. 4 , closely adhere to both ends of the topside of the filter 35 to be supported thereon, respectively. The end portions 125 , as shown in FIGS. 2 to 4 , protrude in a front direction. Meanwhile, the rear support 130 closely adheres to an inner circumference 23 a of the rear panel 23 rotatably supporting the rear side of the drum 20 to be supported thereon. A pair of legs 131 , as shown in FIG. 2 , FIG. 3 , and FIG. 5 , protruding from the body, and more particularly, from both corners of a rear side of the tray 110 are provided to the rear support 130 .
A pair of the legs 131 , as shown in FIG. 5 , are contacted with the inner circumference 23 a of the rear panel 23 to closely adhere thereto. For this, a curved portion 131 a having the same curvature of the inner circumference 23 a of the rear panel 23 is provided to each lower part of the legs 131 . As mentioned in the foregoing description of the present invention, the front support 120 closely adheres to a portion of the front panel 21 , and more particularly, to the filter 35 to be supported thereon, and the rear support 130 closely adheres to the inner circumference 23 a of the rear panel 23 to be supported thereon. Therefore, the dryer rack 100 installed in the drum 20 according to the present invention enables to maintain a stable loaded state even if vibration is generated from the drying operation.
A process of drying an object to be dried using the above-constructed dryer rack 100 according to the present invention is explained as follows. First of all, a user grabbing the grip 15 carries to load the dryer rack 100 in the drum 20 . In doing so, user's hands are not exposed in both right and left directions of the dryer rack 100 . Hence, the user enables to insert the dryer rack 100 in the drum 20 via the opening 21 a conveniently even if the dryer rack 100 has a full-sized right-to-left width. Besides, since the grips 150 are provided to the front part of the dryer rack 10 , the user just lays his hands on the grips 150 in the vicinity of the opening 21 a conveniently. Once the dryer rack 100 is loaded in the drum 20 , the user makes the rear support 130 closely adhere to the inner circumference 23 a of the rear panel 23 to be supported thereon and also makes the front support 120 closely adhere to the portion of the front panel 21 , e.g., the filter 35 , to be supported thereon. After completion of loading the dryer rack 100 in the drum 20 , a drying object is placed on the tray 110 , the door is closed 15 , and the dryer is then actuated.
Once the dryer is actuated, the drum 20 and fan 40 start to rotate as well as the heater 80 it turned on. Air within the drum 20 is then discharged outside via the exhaust duct 30 as well as hot air is supplied to the drum 20 via the air inlet duct 70 . The hot air supplied to the drum 20 dries the drying object placed on the tray 110 of the dryer rack 100 . In doing so, as the hot air passes through the tray 110 upward and downward, it is able to dry the drying object evenly. Besides, as the drying object stays onto the tray 110 of the dryer rack 100 during the drying process, noise and shock fail to occur within the drum 20 .
The air, which becomes humid air after drying the drying object within the drum 20 , is then discharged outside via the exhaust duct 30 . In doing so, particles contained in the humid air are removed by the filter 35 so that clean air can be discharged outside only. Accordingly, the dryer rack according to the present invention facilitates to dry the relatively heavy drying object. It is a matter of course that the noise and shock caused by the fall of the drying object do not occur within the drum while the drying object is dried using the dryer rack. Therefore, the present invention enables to prevent the drum from being broken down and to secure the endurance of the drum.
And, the grips are provided to the dryer rack according to the present invention, thereby facilitating a user to load/unload the dryer rack in/from the drum. Moreover, the grips are tilted, thereby facilitating the user to grab the corresponding grips conveniently. Besides, there is a sufficient margin for designing the right-to-left width of the dryer rack, whereby a large amount of the drying object can be handled at the same time by the dryer. Furthermore, the dryer rack can be loaded/unloaded in/from the drum without danger of injury using the grips.
Moreover, the front and rear supports are provided to the front and rear sides of the dryer rack according to the present invention, respectively and are constructed to closely adhere to the structures supporting them. Therefore, even if vibration is generated from the drying operation, the dryer rack loaded in the drum does not move or rock side to side so that the drying object can be safely dried.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover such modifications and variations, provided they come within the scope of the appended claims and their equivalents. | A dryer rack for use with an apparatus for drying an object inside a drum is disclosed, wherein the dryer rack includes a platform for having an upper surface for supporting the object. The platform may include at least one grip for loading and unloading the dryer rack into an interior space of the drum. The at least one grip is flush with the upper surface of the platform. The at least one grip is formed in a forward portion of the platform, to be near an access point of the drum. | 3 |
INDEX TO RELATED REFERENCES
[0001] This application claims benefit of U.S. Provisional Patent No. 61/121,257 filed Dec. 10, 2008 and U.S. Provisional Patent No. 61/262,978 filed Nov. 20, 2009, the disclosures of which are incorporated herein by reference in their entirety.
BRIEF SUMMARY OF THE INVENTION
[0002] The present invention provides a device and method for delivering chum to a body of water over an extended period of time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is side view of the device in an environment of use.
[0004] FIG. 2 is a partial side cut away of the portion of device.
[0005] FIG. 3 is a cross section of a portion of the device.
[0006] FIG. 3A is a view along section lines B-B from FIG. 3
[0007] FIG. 4 is a partial side cut away of the portion of device from FIG. 5 with arrow indicating placement.
[0008] FIG. 5 is a cross section of a portion of the device.
[0009] FIG. 6 is a bottom view of the device with the lowermost light assembly removed.
[0010] FIG. 7 shows the device with a flexible or fabric material attached.
[0011] FIG. 8 is a partial cross section along section lines C-C from FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The present invention is a chum tube 10 with portions that rest above and below the water line 34 of a body of water. The portion extending above the water line is light extension tube 16 and has a strobe light 80 on its uppermost end. Extending upward from tube 11 is cap 15 upon which light extension tube 16 is affixed.
[0013] Cap 15 is on the upper end of tube 11 . On the interior of tube 11 is air chamber 13 that is bordered on its base by an interior floor 14 , bordered on either side by the interior wall of tube 11 , and bordered in the uppermost edge by cap 15 .
[0014] Below interior floor 14 within tube 11 is an inner cylindrical tube 12 slidably contained therein.
[0015] Chum material 31 is placed within inner cylindrical tube 12 . Inner cylindrical tube 12 is held into an initial fixed position by a medial set screw 25 that applies pressure on one side of inner cylindrical tube 12 and urges inner cylindrical tube 12 against inner portion of wall 11 in a direction opposite medial set screw 25 to seal opening 24 during filling and transport. Closure is accomplished by contact of the outer wall of cylindrical tube 12 against the inside wall of tube 11 sealing opening 24 when screw 25 is tightened against cylindrical tube 12 . It is preferred that opening 24 be sealed during filling and transport of chum tube 10 . Preferably, screw 25 is loosened when chum tube 10 is used such that chum exits opening 24 . Opening 24 is not accessible when screw 25 is engaged because opening 24 is sealed. When screw 25 is disengaged, a chum oil and water mixture 28 exits device 10 .
[0016] Chum mixed with water produces an oil water mixture 28 . Oil is lighter than water and tends to float. Oil from chum 31 exits through opening 24 and openings 20 .
[0017] The lower portion of chum tube 10 has a plate 23 at the lower end. Plate 23 is connected to cylindrical tube 12 and is constructed and arranged to move cylindrical tube 12 in an up and down motion from water movement.
[0018] In one embodiment, plate 23 is formed of a photosensitive material that is at least partially luminescent in light. More particularly, in sunlight, plate 23 appears to glow and the luminescence of plate 23 attracts fish.
[0019] Lower tube openings 20 provide openings for chum material 28 to exit cylindrical tube 12 and ultimately provide chum into the surrounding lower water areas around openings 20 .
[0020] Inner cylindrical tube 12 has, at its lower end, inner cylindrical tube cap 21 which has affixed thereto, lower strobe light 22 . Tube cap 21 has a circumferal threaded portion 32 that is constructed and arranged to attach to threaded portion 33 on the lower end of tube 12 .
[0021] Chum tube 10 is constructed and arranged to float freely. It is also held in place by anchor line 26 a attached on one end to anchor 27 and on an opposite end to medial set screw 25 . Additionally, anchor line 26 b can be attached to a boat.
[0022] In use, cylindrical tube cap 21 is removed to access the open end of inner cylindrical tube 12 . The top of tube 12 is open providing access to the cavity within tube 12 . The bottom of tube 12 has cylindrical tube cap 21 that forms the bottom floor portion of the cavity in tube 12 . The cavity is filled with dry chum 31 and tube 12 is replaced. Any acceptable chum is used. The chum may be a solid, semisolid, liquid, or combinations thereof. A preferred chum is Drychum Concentrate (JanDell Fishing Products, Boyd Tex.).
[0023] Tube 12 slides into tube 11 at opening 19 . Collar 30 prevents tube 12 from sliding out of tube 11
[0024] After chum 31 is loaded into chum tube 10 , it is desirable to tighten screw 25 to prevent chum 31 from exiting chum tube 10 until a desirable time. Screw 25 is preferably an eyebolt that is easily tightened and loosened by hand. A lanyard can be used to secure screw 25 to both tube 11 and the eyelet portion of screw 25 .
[0025] As discussed herein, screw 25 prevents chum 31 from exiting opening 24 until such time as desired by pushing cylindrical tube 12 against and sealing opening 24 .
[0026] Tube 11 is preferably formed of schedule 40 PVC pipe. Schedule 40 PVC is selected due to various characteristics including, but not limited to the fact that it floats in water. In a preferred embodiment, tube 11 is constructed and arranged to be about 18 inches long and to have an inner diameter of about 3 inches.
[0027] The upper portion of tube 11 , as seen in FIG. 2 has air tight interior chamber 13 . Airtight interior chamber 13 prevents tube 10 from sinking and maintains tube 10 at a desired position relative to water line 34 .
[0028] As shown in FIG. 8 , tube 11 has upper collar 11 a. Collar 11 a is constructed and arranged to support spacer 55 . When spacer 55 is positioned on collar 11 a of tube 11 , screw threads 50 remain accessible for eventual connection with lower collar 11 c on lower tube end 11 b. Lower collar 11 c has complementary receiving threads 65 , as shown in FIG. 8 , for connection of upper collar 11 a to lower collar 11 c utilizing complementary screw thread connections 50 and 65 .
[0029] Light extension tube 16 is preferably formed of schedule 20 PVC. Light extension tube 16 is preferably about 24 inches long and has an inner diameter of about 1.25 inches.
[0030] Plate 23 is formed of a fluorescent neon green plexiglass that attracts fish because, in the daytime sunlight, plate 23 refracts light. The refracted light acts as a fish attractor. This refracted light appears to move and is attractive to fish by the natural movement and bobbing of tube 10 when floating in water.
[0031] In a preferred embodiment, chum tube 10 has affixed thereon an ACR strobe light 80 , on top of light extension tube 16 .
[0032] Chum tube 10 is set on the water. Air chamber 13 keeps chum tube 10 afloat and any one or more of anchor line 26 a, anchor line 26 b, or anchor 27 keeps chum tube 10 in an area restricted by the length of anchor line 26 a or 26 b.
[0033] In use, cap 21 is removed from tube 11 , as shown in FIGS. 4 and 5 . Chum 31 is placed within tube 12 and cap 21 is replaced. Chum tube 10 is set on the water. Water enters chum tube 10 through openings 20 and chum 31 subsequently mixes with water that has entered. A mixture of chum and water 28 exits inner cylindrical tube 12 through openings 20 and 24 . Openings 20 are only exposed to the surrounding water when tube 12 extends past below the periphery of interior wall 11 of chum tube 10 . Chum mixture 28 comprises oil and will eventually form surface chum 28 a that will float on or near the water surface 34 .
[0034] The chum that exits openings 20 and 24 attracts fish, as chum is known to accomplish.
[0035] In one embodiment, depicted in FIG. 7 , a fabric or flexible material 35 is attached to device 10 . The material floats and is intended to attract fish.
[0036] While the invention has been described in its preferred form or embodiment with some degree of particularity, it is understood that this description has been given only by way of example and that numerous changes in the details of construction, fabrication, and use, including the combination and arrangement of parts, may be made without departing from the spirit and scope of the invention. | A device and method is for providing fishing chum, over an extended period of time, to a body of water. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 393,618, filed Aug. 14, 1989, now abandoned, which is a continuation of Ser. No. 06/657,091, filed Oct. 2, 1984, now U.S. Pat. No. 4,985,370, and a continuation-in-part of application Ser. No. 564,962, filed Dec. 23, 1983 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to recombinant DNA technology for expressing heterologous proteins in bacteria. More particularly it relates to methods and means for efficient direct expression of prochymosin and mammalian growth hormones in Escherichia coli.
2. Description of the Prior Art
Calf rennin (chymosin) the preferred milk-clotting protease for use in cheese production is in short supply. Alternative milk-clotting agents; namely, fungal proteolytic enzymes have been developed. However, because of their great proteolytic activity, they tend to reduce the yield of cheese and often give bitter flavors.
The economic attractiveness of a steady and sufficient supply of a milk-clotting protease has led several investigators to apply recombinant DNA technology to the problem. Nishimori et al., J. Biochem. 90:901-904 (1981) report cloning of the structural gene of prorennin (prochymosin) in E. coli. In a subsequent publication, Nishimori et al., J. Biochem. 91:1085-1088 (1982), reported the nucleotide sequence of calf prorennin cDNA which they had cloned in E. coli. Construction of an expression plasmid having the lacUV promoter and its ability to produce a fused protein containing almost all of the prochymosin peptide joined to the short N-terminal peptide of E. coli beta-galactosidase is described by Nishimori et al., Gene 19:337-344 (1982).
European Patent Application 73,029 published Mar. 2, 1983 describes calf prorennin DNA-containing plasmids, microorganisms (E. coli) transformed with said plasmids, and their expression of prorennin.
British Patent Application 2,091,271A, published Jul. 28, 1982, discloses methods and agents for producing rennin, prorennin and preprorennin, including the use of various promoters (lac, trp, ura3, etc.) to obtain expression. One of the disclosed DNA sequences that codes for preprorennin has attached to it a transcriptional promoter and a ribosomal binding site at the 5'-end. The distance between the beginning of the DNA which codes for preprorennin and the DNA segment carrying the transcriptional promoter and ribosomal binding site is varied.
British Patent Application 2,100,737A, published Jan. 6, 1983, describes recombinant DNA technology for producing chymosin, methionine chymosin, prochymosin, methionine prochymosin and preprochymosin. Vectors carrying an E. coli trp promoter-operator fragment and a transcription terminator, an initiation codon and a Shine-Dalgarno (SD) sequence which serves as a ribosome binding site are disclosed. Investigation of the effect of spacing between the SD and ATG sequences is also disclosed.
European Patent Application 77,109, published Apr. 20, 1983, describes DNA molecules, i.e., plasmids, comprising genes for preprochymosin and specific DNA sequences such as a double lac UV5 or a modified trp system, and their use to transform microorgamisms (lactobacilli, streptococci, bacillus or yeast) to generate transformants which produce preprochymosin in its allelic and maturation forms.
European Patent Application 36,776, published Sep. 30, 1981 describes expression vectors having the trp promoter-operator from which the attenuation region has been deleted, and methods for their production. Transformants carrying said vectors can be grown up in tryptophan-rich media so that cell growth proceeds uninhibited by premature expression of heterologous peptide encoded by an insert otherwise under control of the trp promoter-operator system.
Emtage et al., Proc. Natl. Acad. Sci. 80:3671-3675, 1983 and Japanese Patent Application No. SHO 58-38,439, filed Mar. 9, 1983, communicated to us by Beppu, describe construction of hybrid plasmids carrying prochymosin cDNA and containing the E. coli trp operon and the use thereof for expression of prorennin at levels greater than those reported by prior investigators A further communication from Beppu disclosed an amendment to said Japanese application, said amendment being filed on Nov. 15, 1983. The amendment relates, in part, to the effect of variation in the distance separating the SD sequence from the initiation codon for prochymosin, and the effect of replacing the N-terminal amino acids of prochymosin by peptides of varying length.
Harris et al., Nucleic Acids Research 10:2177-2187 (1982) report the cloning and nucleotide sequence of cDNA coding for preprochymosin. Goff et al., Gene 27, 35-46 (1984) describe the expression of calf prochymosin in Saccharomyces cerevisiae, a yeast. The restriction endonuclease cleavage map and DNA sequence of preprochymosin cDNA have been published Nishimori et al., J. Biochem., 91:1085-1088, (1982).
Mammalian growth hormones, including human epidermal growth factor (h-EGF), are of considerable interest because of their potential to improve animal husbandry. Their general use has been restricted because of their very limited availability. The economic attractiveness of an adequate supply of said hormones has led several investigators to apply recombinant DNA technology to the problem.
Human epidermal growth factor (EGF) or urogastrone is not only a stimulator of epidermal tissue growth but is also a potent inhibitor of gastric acid secretion. The full potential of EGF has not been investigated primarily because of lack of sufficient material.
The use of recombinant DNA methodology for the manufacture, cloning and expression of a structural gene for urogastrone and of genes for polypeptide analogs thereof are described in International Patent Application No. 83/04030, published Nov. 24, 1983.
The cloning of DNA complementary to bovine growth hormone mRNA, the nucleotide sequence thereof and the corresponding amino acid sequence predicted therefrom are reported by Miller et al., in European Patent Application 47,600, published Mar. 17, 1983 and J. Biol. Chem. 255, 7521-7524 (1980), and by Woychik et al. in Nucleic Acids Research 10, 7197-7210 (1982). British Patent Application 2,073,245A, published Oct. 14, 1981, and Kesket et al., Nucleic Acids Research 9, 19-30 (1981) describe the cloning of bovine growth hormone and its expression in E. coli HB101 as a fused beta-lactamase-bovine growth hormone protein.
Processes for expressing bovine growth hormone gene, plasmids and plasmid hosts for use therein are disclosed in European Patent Applications 67,026 and 68,646, published Dec. 15, 1982 and Jan. 5, 1983, respectively. Each application discloses E. coli as the host organism. The latter application, the counterpart of U.S. Pat. No. 4,443,539 issued Apr. 17, 1984, also divulges Saccharomyces cerevisiae as host organism.
Seeburg et al., DNA, 2 37-45 (1983) report the cloning in bacteria of cDNAs prepared using poly (A)mRNA from bovine or porcine pituitaries and the construction of expression vectors thereform which achieved efficient bacterial production of the mature animal (bovine or porcine) growth hormones. The technique adopted was analogous to that previously described by Goeddel et al., Nature, 281, 544-548 (1979) for direct expression of human growth hormone in E. coli. In each instance the bacterial expression vectors used were under control of the E. coli trp promoter. European Patent Applications Nos. 103,395 and 104,920, published Mar. 21, 1984 and Apr. 4, 1984, describe production of bovine growth hormone-like polypeptide and production of swine growth hormone-like polypeptides, respectively via recombinant DNA methodology.
Administration of bovine growth hormone to dairy cows increases milk production and improves the feed intake to milk output ratio Macklin, J. Dairy Science 56, 575-580 (1973)!. European Patent Application 85,036A, published Aug. 3, 1983, discloses that biosynthetically produced (by rDNA) bovine growth hormone and/or fragments of it also increase milk production in cows and production of meat, wool, eggs and fur in pigs and other farm animals.
U.K. Patent Specification 1,565,190, published Apr. 16, 1980, discloses recombinant plasmid vectors capable of transforming microorganims and containing within their nucleotide sequences subsequences which code for the growth hormone of an animal species. U.S. Pat. No. 4,237,224 describes plasmid vectors for introducing foreign DNA into unicellular organisms.
Plasmids having a HindIII insertion site for a chosen eukaryotic DNA fragment, said site being adjacent to a bacterial promoter such as the trp promoter, wherein the transcription and translation of the DNA fragment are controlled by the promoter, are described in U.S. Pat. No. 4,349,629.
The level of expression of a cloned gene is influenced by a number of factors such as the number of gene copies and the efficiency of transcription and translation. Efficient transcription of an inserted gene requires the presence of a strong promoter and efficient translation requires the presence of a suitable ribosome binding site in the mRNA and appropriate spacing between the rbs and the translation initiation codon. The promoter precedes that portion of the DNA (structural gene) which codes for a protein. The ribosome binding site (rbs), or ribosome recognition sequence, is believed to consist of a sequence at least 3-9 bp long, known as the Shine-Dalgarno (SD) sequence. It begins 3 to 11 bp upstream from the AUG which encodes the amino terminal methionine of the protein Guarante et al., Cell 20:543-553, (1980)!, and is complementary to the 3'-terminal sequence of 16S RNA.
The separation of the promoter from the translational start signal (AUG) for a gene can markedly affect the levels of protein produced (Guarante et al., loc. cit. and references cited therein). This reference and Ptashne et al., U.S. Pat. No. 4,332,892 issued Jun. 1, 1982 describe the effects of placing a "portable promoter" fragment at varying distances from the 5'-end of a gene upon expression.
Other references relevant to the effect of defined alterations of nucleotide sequences and especially of variations between the SD region and the start codon are: Scherer et al., Nucl. Acids Res. 8:3895-3907 (1980); Shepard et al., DNA 1:125-131 (1982); Windass et al., Nucl. Acids Res. 10:6639-6657 (1982); De Boer et al., DNA 2:231-235 (1983); Tacon et al., Molec. gen. Genet. 177, 427-438 (1980); and Itoh et al., DNA 3, 157-165 (1984).
SUMMARY OF THE INVENTION
This invention relates to a promoter-rbs expression element of general utility for high level heterologous gene expression, to expression plasmids carrying said expression element for direct expression of heterologous proteins (prokaryotic or eukaryotic) and which, when introduced into competent bacteria, produce recombinant microorganisms capable of expressing unexpectedly and surprisingly high levels of said proteins; to methods for their construction; recombinant E. coli, especially transformants, comprising said plasmids; and the use of said recombinant microorganisms to produce said heterologous proteins. More particularly it relates to high level expression by E. coli of heterologous genes encoding for proteins such as prochymosin and mammalian growth hormones such as bovine and porcine growth hormones and human epidermal growth factor and especially to expression plasmids useful therefor. Said plasmids comprise a selectable marker; a replicon, i.e., a DNA sequence which comprises a region to control autonomous replication in the host cell; and the E. coli trp promoter joined to said heterologous protein cDNA sequence (gene) by a synthetic DNA linker, said plasmid comprising a novel ribosome binding region which may be of variable length. A feature of the plasmids of this invention is the presence, in the ribosome binding region upstream from the ATG initiation codon, of the nucleotide sequences 5' TAAAAAGGAGAATTC ATG 3' or 5' TAAAAAGGGTATCGAGAATTC ATG 3'. A preferred expression plasmid of this invention has the additional and significant feature of a translational stop codon (TAA) in the same reading frame as the protein coding sequence just prior to the Shine-Dalgarno sequence.
The state of the art of molecular biology is at a sufficiently developed level such that in vitro construction of hybrid plasmids which should express a given protein or polypeptide is possible from a knowledge of the cDNA sequence which encodes said polypeptide and the restriction endonuclease cleavage-map of said sequence. However, despite this, there is no basis in the art to suggest that a particular, and even critical, arrangement of the DNA sequence within a plasmid will, when suitably introduced into a microorganism, afford significant and unexpectedly high expression of the polypeptide.
The herein described recombinant microorganisms express heterologous proteins in significantly greater yields than do previously described microorganisms and achieve, for the first time, their economic production via recombinant DNA technology.
As those skilled in the art will recognize, recombinant microorganisms can be produced by a number of methods, e.g. transformation, transduction, conjugation or transfection. It is, therefore, intended to include in the term "recombinant microorganisms" microorganisms which are capable of expressing the herein described heterologous proteins whenever said microorganisms are prepared by any of the above-mentioned methods. To put it another way, the definition of recombinant microorganism as used herein includes any microorganism capable of expressing the heterologous protein of a heterogenic or xenogenic sequence whenever said microorganism is prepared by recombinant techniques.
Another object of this invention comprises the nucleotide sequences described herein for the ribosome binding site of a gene encoding a prokaryotic or eukaryotic protein which when inserted into a bacterial plasmid downstream from a transcriptional promoter sequence affords efficient expression in E. coli. The ribosome binding site regions described contain a convenient EcoRI restriction endonuclease cleavage site just upstream from the ATG initiation codon, providing for a method for inserting any DNA fragment containing a protein translational start codon into the expression vectors behind the SD sequence. In other words, the gene in the expression plasmids described herein could be any gene coding for a prokaryotic or eukaryotic protein. For example, the herein described nucleotide sequences between the ribosome binding site and ATG initiation codon afford high expression of cDNA sequences, such as, prochymosin (prorennin), bovine growth hormone, porcine growth hormone, and human epidermal growth factor (urogastrone). The proteins, bovine and porcine growth hormones and human epidermal growth factor, are collectively referred to herein as mammalian growth factors.
Bacterial production of a particular heterologous gene can result in a polypeptide which may or may not have a methionine residue at the amino terminus of said polypeptide. Therefore, the term "prochymosin" (prorennin) as used herein is intended to include methionine prochymosin (prorennin) and prochymosin (prorennin). The same applies to the other polypeptides described herein. Further, when reference to "chymosin" (rennin) is made herein it is intended to include within said term the known allelic forms thereof (e.g. A, B, etc.).
The following examples are intended to illustrate more fully the nature of the invention without acting as a limitation upon its scope.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 presents the overall scheme for construction of plasmids pPFZ-R2 and R4 (pPFZ-R), including the restriction map of said plasmids which is common to each of pPFZ-R2 and R4. The arrow indicates the direction of expression from the trp promoter sequence into the prochymosin (prorennin) gene (represented by the heavy segment). The synthetic insert is represented by the open box.
FIG. 2 depicts the scheme for construction of plasmids ptrpLI-R2 and R4.
FIG. 3 presents the scheme for construction of plasmids ptrpLI-R2-B48 and ptrpLI-R4-B48.
FIG. 4 presents the nucleotide sequence and spacing between the ribosome binding site and initiation codon (ATG) of the prochymosin (prorennin) gene for each of plasmids pPFZ-R2 and pPFZ-R4. This is the only region in which said plasmids differ in nucleotide sequence.
FIG. 5. Scheme for construction of plasmids containing the full length bGH gene and expression sequences. Plasmid pBGH-102 contains the bGH cDNA sequences (dark box) cloned into the ampicillin resistance gene in pBR322. The synthetic DNA coding for a new amino terminus of bGH was inserted into the EcoRI and HindIII sites of pBR322 (dotted box). Various in vitro manipulations were performed to construct a plasmid, pBGH-212, that carries the complete modified bGH gene. Plasmid pBGH-212 was cleaved with EcoRI and DNA fragments containing different variations of the trp promoter-operator sequence were inserted. Arrows show 5'→3' direction of coding sequence, or direction of transcription.
FIG. 6. Construction of a bacterial expression plasmid for bGH production. Plasmids pBGH-212-R carry a gene for the direct expression of mature bGH complete with trp promoter sequence (see FIG. 5). These plasmids were cleaved with HindIII, followed by partial digestion with PvuII, and two approximately 920 bp HindIII-PvuII fragments isolated. A synthetic DNA fragment coding for the C-terminus of bGH was inserted into the EcoRI and HindIII sites of pBR322 (white box). This subclone was cleaved with PvuII and BamHI, and the 365 bp DNA fragment was isolated. The large vector fragment (3995 bp) was isolated from pBR322 after cleavage with HindIII and BamHI. The two promoter-bGH gene containing fragments (920 bp) were separately mixed with the synthetic DNA containing fragment (365 bp) and the vector fragment (3995 bp). The mixtures were ligated with T4 ligase and used for transformation of competent E. coli HB101. The different bGH expression plasmids are referred to as pBGH-301, and pBGH-375. The arrows indicate the direction of transcription from the trp promoter sequence and the 5'→3' direction in the coding sequence.
FIG. 7. Construction scheme for plasmids containing the full length pGH gene and expression sequences. Plasmid pGH-24 contains the pGH cDNA sequences (dark box) cloned into the ampicillin resistance gene in pBR322. The synthetic DNA coding for a new amino terminus of pGH was inserted into the EcoRI and HindIII sites of pBR322 (dotted box). Various in vitro manipulations were performed to construct a plasmid that carries the complete modified pGH gene. This plasmid was cleaved with EcoRI and DNA fragments containing different variations of the trp promoter-operator sequence were inserted. Arrows show 5' to 3' direction of coding sequence, or direction of transcription.
DETAILED DESCRIPTION OF THE INVENTION
The Microorganisms
The microorganisms and recombinant microorganisms used and/or produced in this invention and the depositories from which they are available are listed below:
E. coli C600, also known as CR34, ATCC 23724
E. coli HB101 NRRLB-11371, ATCC-33694
E. coli MM294 ATCC-33625
E. coli W3110 ATCC-27325
E. coli HB101 comprising pPFZ-R2 ATCC-39544
E. coli HB101 comprising pPFZ-R4 ATCC-39543
As those skilled in the art will recognize, any transformable E. coli K-12 strain can be used in this invention as host organism in place of those enumerated above. Further, protease negative strains of E. coli will, as the skilled artisan appreciates, afford equal or better results than the above-mentioned E. coli strains.
The above-identified recombinant microorganisms ATCC 39543 and 39544 were deposited on Dec. 14, 1983 under the terms of the Budapest treaty in the American Type Culture Collection, Rockville, Md., a recognized depository affording permanence of the deposits and ready accessibility thereto by the public if a patent is granted on this application. They were given the accession numbers shown above. The deposits are available during pendency of this application to one determined by the Commissioner of the United States patent and Trademark Office to be entitled thereto under 37 CFR 1.14 and 35 USC 122, and in accordance with foreign patent laws in countries wherein counterparts of this application, or its progeny, are filed. All restrictions on the availability to the public of the microorganism deposited will be irrevocably removed upon granting of the patent.
Preparation of RNA and Cloning of cDNA
Total RNA from animal pituitaries was obtained from a local slaughterhouse and was isolated by the procedure of Ullrich et al., Science 196, 1313-1319 (1977). Polyadenylated RNA was obtained from total RNA by chromatography on oligo(dT)cellulose. Double-stranded cDNA was prepared from this RNA and a size fraction of the cDNA was cloned by standard methods in E. coli using plasmid pBR322 and the homopolymer method as described previously (Miller, W., et al. 1980, J. Biochem., 255, 7521, Goeddel et al., 1979; Nature 281, 544-548; Seeburg et al., 1983, DNA 2, 37-45).
Colonies transformed with cDNA containing plasmids were replica plated onto nitrocellulose filters. Filters containing transformant colonies were processed for hybridization according to the procedure described by Grunstein and Hogness (1975, Proc. Natl. Acad. Sci. 72, 3961-3965). Radioactively labeled synthetic oligonucleotides whose sequence was derived from published cDNA sequences were used as probes for detecting the cloned cDNAs. Hybridizing colonies were grown in 5 ml. LB, and plasmid DNAs prepared and cloned sequences characterized by cleavage with restriction endonucleases followed by electrophoresis of DNA fragments in gels.
The Starting Plasmids
Plasmid, pCR101 is described by Nishimori et al., Gene, 19:337-344 (1982). It carries the full-length cDNA of prochymosin, the gene for ampicillin resistance, and consists of 5678 bp. It includes a cleavage site for HindIII and several BamHI sites.
Plasmid ptrpLI is described by Edman et al., Nature 291:503-506 (1981), and plasmid pBR322 by Bolivar et al., Gene 2:95-113 (1977).
Materials
Restriction endonucleases (AsuI, BamHI, EcoRI, HindIII, ClaI, HinfI, KpnI, PstI, PvuII, RsaI, SalI), T4 ligase, and DNA polymeraseI (large fragment) were purchased from New England Biolabs, T4 polynucleotide kinase from PL Biochemicals, bacterial alkaline phosphatase from Bethesda Research Laboratories (BRL), calf intestine alkaline phosphatase from Boehringer Corp. All enzymes were used under conditions recommended by the supplier. Radiochemicals were purchased from New England Nuclear (NEN). Protein molecular weight standards were purchased from BRL, purified bovine chymosin was purchased from Sigma Chemical Company (Sigma) and purified bGH from Miles.
Bacteria were grown routinely at 37° C. in L Broth or on L-agar plates (Miller, J. Experiments in Molecular Genetics, Cold Spring Harbor Laboratory, New York, p. 433, 1972) containing either ampicillin (25 μg/ml) or tetracycline (10 μg/ml). For large scale plasmid preparation, log phase cultures were amplified by the addition of chloramphenicol (170 μg/ml) Clewell and Helinski Helsinki, J. Bacteriol. 110:1135 (1972)!.
The plasmid pBGH-7 comprises a pBR-322 that contains a full length cDNA of bGH cloned into the PstI site and was prepared as described by Miller, W. et al., J. Biochem. 255, 7521 (1980). The cloned cDNA contains approximately 830 bp including 31 bp of the 5' untranslated sequence, the entire pre-hormone structural sequence (651 bp), the entire 3' untranslated region (104 bp), a brief stretch of poly(A), and the dC-dG tails. The plasmid pGH-24 comprises a pBR322 that contains a full length cDNA of pGH cloned into its PstI site and was prepared by methods similar to those described by Seeburg et al. DNA 2, 37-45 (1983). The pGH-24 plasmid DNA was constructed and provided by Dennis Pereira. The plasmid pBR-322 was previously described by Bolivar et al. Gene 2, 95-113 (1977).
Synthesis of Oligonucleotides
Synthetic oligonucleotides 5'.AGAATTCATGG.3' (I) and 5'.CCATGAATTCT.3' (II) were chemically synthesized by the phosphite method Caruthers, J. Am. Chem. Soc. 103, 1385 (1981)! and were purified from 6M urea-20% poly-acrylamide gels.
The 18-bp and 22-bp single stranded oligomers were synthesized by methods described herein and were transformed to a 40-mer adapter also as described herein. Double stranded 40-mer is produced by annealing and ligating the single stranded 18- and 22-mers according to known procedures.
The oligonucleotides used for pGH and bGH were synthesized via the phosphoramidite procedure of Caruthers et al, Tetrahedron Lett. 24, 245 (1983) and fragments were synthesized from single-stranded oligomers 11-16 bases long.
Molecular Cloning Reactions
The fill-in reaction of recessed 3' ends of double-stranded DNA using Klenow fragment of E. coli DNA polymerase I was essentially as described by Maniatis et al. Molecular Cloning, A Laboratory Manual, Cold Spring Harbor Laboratory p. 113 (1982)!. The transfer of the gamma-phosphate of ATP to the 5'-OH terminus of the synthetic linker DNA by T4 polynucleotide kinase was as described by Maniatis (ibid.). About 2 μg of double stranded linker DNA was phosphorylated in a 20 μl reaction mixture containing 70 mM Tris (pH 7.6), 10 mM MgCl 2 , 5 mM dithiothreitol (DTT), 20 μCi gamma-32P!ATP (5000 Ci mmol -1 ; NEN), T4 polynucleotide kinase (10 units) was added and the reaction allowed to proceed at 37° C. for 15 minutes; 1 μl of 10 mM ATP and 10 units of T4 kinase were then added and the reaction allowed to proceed for an additional 30 minutes at 37° C. The kinased linkers were stored at -20° C.
When necessary the terminal 5' phosphates were removed from DNA by treatment either with bacterial alkaline phosphatase (BAP) or with calf intestinal alkaline phosphatase (CIP) Chaconas et al. Methods Enzymol. 65:75 (1980)!. Briefly, in the CIP treatment, the plasmid DNA was digested to completion with the appropriate restriction enzyme(s) and precipitated in ethanol. The DNA pellet was resuspended in CIP reaction buffer (0.1M glycine, 1 mM MgCl 2 , 0.1 mM ZnCl 2 , pH 10.4) at a final concentration of 1 μg per 10 μl buffer. The sample was heated to 65° C. for 10 minutes, then cooled on ice for 5 minutes. The calf intestinal alkaline phosphatase was then added to a final concentration of 0.5 units of enzyme per 1 μg of DNA. The mixture was incubated at 37° C. for 30 minutes followed by phenol-chloroform extraction, and ethanol precipitation of DNA fragments. The DNA pellet was resuspended in distilled water to a final concentration of 100 μg/ml.
In the case of BAP treatment, the plasmid DNA was cleaved with the restriction endonuclease(s) of choice and precipitated in ethanol. The DNA pellet was resuspended in buffer (50 mM NaCl, 10 mM MgCl 2 , 10 mM Tris, 10 mM DTT) at a final concentration of 1 μg per 10 μl of buffer. The reaction mix was heated to 65° C. for 10 minutes and quenched on ice. The bacterial alkaline phosphatase was added to a final concentration of 50 units of enzyme per 1 μg of DNA. The reaction mixture was incubated at 65° C. for 2 hours followed by phenol-chloroform extractions, and ethanol precipitation of the DNA fragments.
The construction of the bacterial expression plasmids involved manipulations that joined DNA fragments from various plasmids. All steps are shown in the accompanying Figures. Generally, DNA fragments were purified following isolation from gels and ligated to other fragments or plasmid DNA in 20-50 μl of 66 mM Tris-HCL (pH 7.6), 5 mM MgCl2, 1 mM ATP, 20 mM DTT and 1 μl T4 ligase (400 units). Competent cells of E. coli were prepared and transformed with one half of the ligation mixture using standard procedures Mandel et al., J. Mol. Biol. 53, 1543 (1970).
DNA Sequence Determination
DNA sequences were established by the chemical degradation method Maxam, A. and Gilbert, W. Methods Enyzmol. 65:499-560 (1980)! utilizing end-labeled DNA fragments. Each ribosome binding site region was independently sequenced several times on both strands.
Preparation of Plasmid DNA
Large scale preparations of plasmid DNA were prepared by the alkaline-SDS procedure previously described Birnboim, et al., Nucleic Acid Res. 7:1513 (1979)! followed either by ethidium bromide-CsCl buoyant density centrifugation or fractionation on a Biogel A-50 (BioRad) column as described by El-Gewely et al., Anal. Biochem. 102:423-428 (1980)!. Miniprep amounts of DNA were prepared by a rapid modification of the alkaline-SDS procedure Birnboim et al., Ibid.!.
Gel Electrophoresis
Agarose slab gels, 0.7% to 1% were run according to the conditions described by Maniatis et al. (loc. cit., p. 150-164). Gels were stained for 15 minutes with 1 μg/ml ethidium bromide and photographed under illumination from 266 nm U.V. light using Polaroid film (Type 57, ASA 3000) with a Kodak Wratten filter (23 A).
Acrylamide gels (20×15×0.15 cm) of 5% to 12.5% were used to identify small (less than 1.5 kb) restriction fragments according to the method described by Maniatis et al., Biochemistry 14:3787-3794 (1975)!. Gels were stained and photographed as for agarose gels.
DNA fragments were purified from gel slices by electroelution in a dialysis bag containing 0.1×TBE (8.9 mM Tris-borate, 8.9 mM boric acid, 0.2 mM EDTA). Identification of Heterologous Protein Produced in E. coli
Bacterial cultures containing pBR322 or the expression plasmids (pPFZ-R2 or pPFZ-R4) were grown overnight in LB broth or M9CA medium (Maniatis et al., loc. cit.) containing 4 μg/ml thiamine, 25 μg/ml ampicillin, and 100 μg/ml tryptophan. These cultures were diluted 1:25 into M9CA medium (Maniatis et al. loc. cit., without tryptophan to allow complete induction of the trp promoter), or M9CA medium plus 100 μg/ml tryptophan (to inhibit induction of the trp promoter), or LB medium (for a negative control), and grown in shaker flasks to cell densities of A 560 =1.0. For total cell protein extraction, cell pellets equivalent to 200 μl culture were lysed in 2% sodium dodecyl sulfate (SDS), 1% β-mercaptoethanol, and protein was precipitated with 10 volumes of cold acetone. Precipitated protein was redissolved in SDS sample buffer and aliquots were electrophoresed on 10% or 12.5% SDS-polyacrylamide gels Laemmli, Nature 227:680-685 (1970)!. For labeled protein preparation, cell pellets from 1 ml aliquots of expression cultures were suspended in 1 ml supplemented M9CA medium (M9CA salts, 0.2% glucose, 4 μg/ml thiamine, 20 μg/ml standard amino acids except methionine and tryptophan) plus 25 μg/ml ampicillin and 75 Ci 35 S methionine (NEN; 970 Ci/mmol). After one hour incubation at 37° C., cells were pelleted and resuspended in 200 μl 10 mM Tris (pH 8.0) 1 mM NaEDTA, then placed on ice for 10 minutes following additions of lysozyme to 1 mg/ml, NP40 to 0.2 percent, and NaCl to 0.35M final concentration. The lysate was adjusted to 10 mM MgCl 2 and incubated on ice for 30 minutes with 50 μg/ml DNase I (Sigma). Insoluble material was removed by mild centrifugation and this pellet fraction was dissolved in SDS sample buffer. Supernatant samples were immunoprecipitated with rabbit anti-prorennin antibody (Nishimori et al, Gene 19, 337-344) and staphylococcal adsorbent (Pansorbin; Cal Biochem) as described by Kessler J. Immunology 117:1482-1490 (1976)!. The samples were subjected to SDS polyacrylamide gel electrophoresis (Laemmli, loc. cit.) and enhanced (Enlightning; NEN) before fluorography at -75° C. with Kodak XAR-2 film and a Cornex Lightning Plus intensifying screen.
Quantitation of Expression Levels
Estimations of the amount of heterologous protein produced by expression cultures were determined by densitometer scanning of protein gels containing total protein extracts from bacterial cultures. Individual lanes of the SDS-polyacrylamide gel of total cell protein extracts were analyzed using a Beckman DU-8B densitometer gel scan. The dried-down Coomasie-blue stained SDS-polyacrylamide gel was scanned in each lane to determine the percent of the total cell protein in the heterologous protein band. A scan of the total cell protein from a control culture (containing the pBR322 vector) was used to determine the native protein content in the region of the gel corresponding to the size of the recombinant product. After correcting for the background peaks apparent in the control culture, the expression levels were estimated as a percent of the total cell protein. The protein gels were scanned at 579 nm. Results
Construction of ptrpLI-R2 and ptrpLI-R4
The plasmid ptrpLI is a pBR322 derivative that contains part of the E. coli trp promoter operator and the Shine-Dalgarno (SD) sequence of trpl on a (˜360 bp) HindIII-ClaI fragment. Edman et al., Nature 291:503-506 (1981)!. This vector is, therefore, an expression plasmid with an unique ClaI cloning site adjacent to the trp regulatory region. Inserted DNAs must contain within their sequence an ATG translational initiation codon prior to the gene coding sequence which when inserted into ptrpLI will be properly spaced relative to the trpl ribosome binding site sequence. This expression vector was modified by inserting appropriate synthetic DNA linkers into the ClaI site as illustrated in FIG. 2.
A specific double stranded synthetic DNA linker was used to alter the nucleotide content around the ClaI restriction site of ptrpLI. About 10 μg of ptrpLI DNA was digested with 16 units of restriction endonuclease ClaI for 90 minutes at 37° C. The cohesive ends generated by the ClaI cleavage were blunted in a 100 μl reaction mixture containing 50 mM Tris-HCl (pH 7.2), 10 mM MgSO 4 , 0.1 mM dithiothreitol, 0.2 mM dGTP, 0.2 mM dCTP. Klenow fragment of DNA polymerase (30 units) was added and the reaction allowed to proceed at 20° C. for 45 minutes. After phenol and chloroform extraction, the indicated phosphorylated deoxyoligo-nucleotide linker ˜60 pmoles)
(5' AGAATTCATGG 3') (3' TCTTAAGTACC 5')
was combined with ˜1 μg (˜0.6 pmoles) of the filled-in vector fragment and ethanol precipitated. These fragments were ligated at 4° C. for 18 hours in 30 μl of 66 mM Tris-HCl (ph 7.6), 5 mM MgCl 2 , 1 mM ATP, 20 mM dithiothreitol and 800 units of T4 DNA ligase. The mixture was digested for 90 minutes with 3 units of EcoRI for 90 minutes. The EcoRI cleaved plasmid DNA was re-ligated at 4° C. for 4 hours in 100 μl of 66 mM Tris-HCl (pH 7.6), 5 mM MgCl 2 , 1 mM ATP, 20 mM DTT, and 400 units of T4 DNA ligase. Competent cells of E. coli strain HB101 were transformed with 25 μl of the ligation mixture. Mandel et al., J. Mol. Biol. 53:154 (1970)!. Plasmid DNA was prepared from 12 of the transformants and digested with EcoRI and HindIII. Ten of these plasmids contained the desired ˜360-bp EcoRI-HindIII fragment. DNA sequence analysis verified that one of these plasmids (ptrpLI-R4) had the desired orientation of the synthetic linker and desired sequence at the junctions between the trp promoter and synthetic DNA.
During the DNA sequencing analysis of plasmid DNA from various transformants, it was discovered that one of the plasmids (ptrpLI-R2) had a 6-bp deletion in the region of the ribosome binding site. This deletion most likely resulted from the 3' to 5' exonuclease activity of the Klenow fragment of DNA polymerase I because the linker sequences are all present. It was recognized that this derivative had an altered ribosome binding site compared to the native trp SD sequence contained in ptrpLI-R4.
Cloning of the Synthetic Prorennin Adapter
The sequence of the synthetic double-stranded DNA used to modify the amino terminal end of prorennin is shown:
18 BamHI 22>-------------------->CATGGCTGAGATCACTAGGATCCTAGTGATCTCAGCCATGGTACCGACTCTAGTGATCCTAGGATCACTAGAGTCGGTAC<---------------------<-----------------
This fragment was assembled from 2 single stranded oligomers, 18-bp and 22-bp long. This synthetic DNA encodes the artifical ATG initiation codon for protein synthesis and the first several codons of prorennin sequence as reported by Nishimori et al., J. Biochem. 91:1085-1088 (1982)! in an inverted repeat around a BamHI site. This synthetic DNA was subcloned into the EcoRI restriction site of pBR322 that had previously been treated with the Klenow fragment of DNA polymerase I to fill in the cohesive ends. Subclones were identified by in situ colony hybridization of recombinant microorganisms using radioactively labeled 22-mer as probe Grunstein, M. and Hogness, D., Proc. Natl. Acad. Sci. 72:3961 (1975)!. Plasmid DNA was prepared from 20 hybridization positive colonies and cleaved with BamHI or EcoRI to identify the subclone containing the desired plasmid. Approximately 100 μg plasmid DNA from recombinant microorganism #17 was cleaved with EcoRI and the 40 bp fragment was isolated on a 12.5% polyacrylamide gel. The purified 40 bp EcoRI fragment was inserted into the EcoRI sites of the 2 expression plasmid derivatives (ptrpLI-R2 and ptrpLI-R4) which had been previously cleaved with EcoRI and dephosphorylated by treatment with calf intestinal alkaline phosphatase. Plasmid DNA from several recombinant microorganisms of each ligation was prepared and digested with BamHI restriction endonuclease. Plasmids containing the 40 bp prorennin adapter inserted downstream from the trp expression sequence were identified by the presence of two BamHI sites approximately 700 bp apart. This construction scheme is illustrated in FIG. 3. These expression plasmids were referred to as ptrpLI-R2-B48 and ptrpLI-R4-B48.
These recombinant microorganisms were used as the source for an approximately 370 bp HindIII-BamHI DNA fragment containing the trp promoter-operator sequence, the ribosome binding site, the artifical ATG initiation codon, and the chemically derived sequence coding for the first 5 amino acid residues of prorennin. The nucleotide sequences downstream from the promoter, in the region of the ribosome binding site, differ due to the previous insertion of a different chemically synthesized deoxyoligonucleotide linker at the ClaI restriction site in the plasmid vector ptrpLI as described above. The resulting nucleotide content and spacing between the ribosome binding site (rbs) sequence and the ATG of the prorennin gene, and for other protein encoding genes disclosed herein, was shown by DNA sequence analysis to be as follows for each of the expression constructions:
______________________________________pPFZ(R) 5'→3' Spacing (bp)______________________________________R2 AAGGAGAATTC ATG 5R4 AAGGGTATCGAGAATTC ATG 11______________________________________
Each ribosome binding site variation was used to make prorennin expression plasmids in order to later examine the possible effects that rbs nucleotide sequence content and spacing have on protein expression levels.
Construction of the Prorennin Expression Plasmids
The experimental steps used for constructing the prorennin expression plasmids are illustrated in FIG. 1. First, the 4772 bp vector fragment containing the plasmid replicon, the ampicillin resistance marker, and the desired prorennin coding sequence (from amino acid codon 83 to the stop (TGA) codon) was prepared by digesting 30 μg pCR101 plasmid DNA with HindIII and KpnI restriction endonucleases. The restriction reaction was electrophoresed on a 1% agarose gel and both DNA fragments were isolated from gel slices by electroelution. The 906-bp HindIII-KpnI fragment containing the amino terminal portion of the prorennin cDNA sequence was further digested by BamHI followed by electrophoresis on a 5% polyacrylamide gel. The 235-bp BamHI-KpnI fragment (encoding amino acid codons 6 to 83) was electroeluted from a gel slice.
The HindIII-BamHI DNA fragments containing the expression sequences from the different ptrpLI-R-B48 derivatives were separately mixed in approximately equal molar ratio with the two restriction fragments derived from pCR101 (4772 bp and 235 bp). The mixtures were ligated by addition of T4 DNA ligase and a portion of each ligation mix used for introduction into competent HB101 cells. Colonies were obtained in each instance when cells were selected on LB agar plates containing ampicillin (25 μg/ml). Several drug resistant colonies from the aforementioned colonies were picked into 5 ml LB cultures, and plasmid DNA was subjected to restriction enzyme analyses. In each group, most recombinant microorganisms were found to contain the complete prorennin gene recombined adjacent to the trp promoter-rbs sequence.
Restriction endonuclease analysis of these expression plasmids showed they contained the entire prorennin coding sequence properly aligned for direct expression of prorennin. DNA sequence analysis by the chemical degradation method of Maxam and Gilbert supra of most of the prorennin gene, the in vitro junction region and the trp promoter-operator region confirmed that the artificial initiation codon and the prochymosin coding sequence directly follows the E. coli trp promoter-operator and served to establish the separate identity of the two expression plasmids at the nucleotide level. The two prorennin plasmids constructed here have been designated as pPFZ-R2 and pPFZ-R4. Further, the ATG initiation codon follows the E. coli ribosomal binding site of the trp leader peptide by 5 and 11 nucleotides in expression plasmids pPFZ-R2 and pPFZ-R4, respectively.
Translation of the DNA sequence of these expression plasmids predicts a prorennin protein of 366 amino acids. The estimated molecular weight of such a polypeptide is about 41,000. When E. coli containing an expression plasmid is grown in minimal media lacking tryptophan, the cells produce a protein that migrates slightly larger than mature chymosin (about 36,000 daltons) in SDS-polyacrylamide gel electrophoresis Laemmli, U. K. Nature 227:680 (1970)!. No such protein is produced by E. coli cells containing the vector plasmid pBR322 grown under identical conditions. Very little prorennin protein is produced by identical expression recombinants grown in M9CA media containing an abundance of tryptophan (100 μg/ml), implying that production in E. coli of the putative prochymosin protein is under control of the trp promoter-operator as designed.
Evaluation of Prorennin Synthesis by Expression Cultures
E. coli transformants carrying the prorennin expression plasmids pPFZ-R2 and pPFZ-R4 were grown in M9CA media lacking tryptophan for induction of the trp promoter. Cells were grown in shaker flasks to an OD 550 of 1.0. Cell pellets from these cultures were lysed in 2 percent SDS, 1 percent beta-mercaptoethanol, and proteins were precipitated with acetone. Precipitated proteins were redissolved in SDS sample buffer and aliquots were electrophoresed on 10 percent SDS-polyacrylamide gels Laemmli, Nature 227:680 (1970)!. Prorennin levels were determined by densitometer gel scans of the Coomassie blue stained gel at 579 nm.
It has been observed by phase contrast microscopy that refractile inclusion bodies exist in E. coli cells containing the prochymosin expression plasmids. Control cells containing the plasmid vector pBR322 when grown under identical conditions reveal no such refractile inclusion bodies. Analogous observations have been reported with respect to genetically engineered microorganisms which produce exogenous gene products Carrier et al., Trends in BioTechnology 1:109 (1983)!, such as insulin and thymosin. The retractile bodies are considered to be pools of the expressed foreign protein.
The presence of refractile inclusion bodies appears to directly correlate with a high level of prorennin production.
The above-described bacterially synthesized prochymosin specifically reacts with prorennin anti-bodies.
Evaluation of the growth of recombinants of E. coli HB101 carrying plasmids pPFZ-R2 and pPFZ-R4 under identical shaker flask growth conditions showed that plasmid pPFZ-R2 reproducibly produced prorennin levels ranging from 10 to 15%, and pPFZ-R4 produced prorennin levels ranging from 5 to 7%.
______________________________________ Expression Percent of Total CultureStrain Plasmid Cell Protein* O.D. 550______________________________________HB101 pPFZ-R2 13.1 0.5 pPFZ-R4 7.1 0.5HB101 pPFZ-R2 11.6 0.1 10.2 0.6HB101 pPFZ-R2 15.4 0.3 11.7 0.5 pPFZ-R4 7.0 1.0______________________________________ *Based on densitometer scans of SDSpolyacrylamide gels.
The only difference between the two prorennin expression constructions (pPFZ-R2, and pPFZ-R4) in terms of nucleotide composition occurs in the sequences around the ribosome binding site and initiator codon of the prorennin gene. Yet there is significant variation in the levels of prorennin expression between cultures containing the different plasmids. The observed differences in prorennin expression can be attributed to the differences in the primary DNA sequence around the ribosome binding site. As first noted by Shine and Dalgarno (1974, Proc. Natl. Acad. Sci PNAS 71:1342-1342), there is a purine-rich sequence centered about 10 nucleotides upstream from the initiator codon that is complementary to the 3'-terminal sequence of 16S ribosomal RNA. An overwhelming body of evidence now supports the role of mRNA to rRNA base pairing in the selection of protein synthesis initiation sites by E. coli ribosomes. Ribosome binding sites from many bacterial and phage mRNAs have been sequenced and a consensus Shine-Dalgarno sequence has been determined to be: TAAGGAGGT. Three parameters influence the efficiency of the Shine-Dalgarno interaction: 1) the length of complementarity; 2) the distance between the Shine-Dalgarno sequence and the initiator codon; and 3) the extent to which the Shine-Dalgarno sequence is masked by secondary structure.
Examination of the area around the S.D. sequence of each of the above two expression plasmids:
______________________________________ spacingDNA (Consensus) Sequence (bp)______________________________________S.D. TAAGGAGGTtrpL AAGTTCACGTAAAAAGGGTATCGACA ATG 7pPFZ-R2 AAGTTCACGTAAAAAGGAGAATTC ATG 5pPFZ-R4 AAGTTCACGTAAAAAGGGTATCGAGAATTC ATG 11______________________________________
shows that the length of the complementarity in pPFZ-R2 is 6 contiguous nucleotides, whereas the other has only 3 contiguous nucleotides. Also, the spacing between the ribosome binding site and the initiator codon is 5 nucleotides in pPFZ-R2, which is very close to the spacing in the natural trpl gene initiator region where 7 nucleotides intervene; whereas, pPFZ-R4 has 11 nucleotides between the ribosome binding site and initiator codon. Another important feature of efficient ribosome binding sites recognized in pPFZ-R2 is a translational stop codon (TAA) in the same reading frame as the prorennin coding sequence just prior to the Shine-Dalgarno sequence. All these features of the pPFZ-R2 DNA sequence play a role in its highly efficient prorennin expression.
The degeneracy of the genetic code, of course, affords a certain degree of variation in composition of a given nucleotide sequence without altering the amino acid sequence of the protein encoded by said sequence. Thus, two or more different base sequences (synonymous codons) can be substituted in a given nucleotide sequence without changing the identity of the amino acids specified thereby. Further, it is possible to delete codons or to substitute one or more codons by codons other than degenerate codons to produce a structurally modified polypeptide but one which has substantially the same utility or activity of the polypeptide produced by the unmodified DNA molecule. Said two polypeptides are functionally equivalent, as are the two DNA molecules which give rise to their production, even though the differences between said DNA molecules are not related to degeneracy of the genetic code.
The codon for the 44 amino acid, threonine, is ACT instead of ACC. Due to the redundancy of the genetic code this does not change the amino acid at this position. Since this scheme employs the construction of a hybrid gene in which the section coding for the N-terminal portion of the hormone is made synthetically, the synthetic DNA allows for the design of a new coding sequence for that portion of prorennin. Because the amino acid sequence of prorennin is exactly maintained due to the redundancy of the genetic code, these kinds of sequence changes are insignificant and the gene produces an equivalent polypeptide to that produced in nature (with the exception of the N-terminal met).
The isolation of methionine prorennin expressed by bacterial (E. coli) transformants of this invention, its conversion to rennin and the milk-clotting activity of said rennin was demonstrated by the methodology described in British Patent Application 2,100,737A and by Emtage et al., Proc. Natl. Acad. Sci. 80:3671-3675 (1983).
Plasmids carrying an E. coli trp promoter-operator fragment, an ATG initiation codon, either the ribosome binding site comprising R2 or R4, and cDNA gene sequences encoding bovine growth hormone, porcine growth hormone or human epidermal growth factor have also been constructed, and when introduced into E. coli, resulted in highly efficient expression of the heterologous proteins. The nucleotide sequence of the vector, promoter, and ribosome binding site up to the ATG initiation codon were essentially the same as described above for the prorennin expression plasmids. The expression levels of the heterologous protein produced by these various constructs were determined by SDS-polyacrylamide gel electrophoresis followed by scanning densitometry. The relative levels of expression obtained with these cultures were similar to those observed with prorennin expression. That is, animal growth hormone expression plasmids containing the R2 version of the ribosome binding site exceeded the expression levels of the R4 version by approximately 4 to 5 fold; the ultimate expression level in E. coli cells was around 25% to 30% of the total cellular protein.
The scheme used to achieve expression of the bGH and pGH genes was essentially the same as the method published by P. Seeburg et al.(1983, DNA 2137-45) for the expression of animal growth hormones. It confirmed construction of a composite gene consisting of a cloned synthetic DNA and cloned cDNA sequences. This construction design allowed for the direct expression in E. coli of bGH and pGH without the signal sequence by introducing a translation initiation codon for the first amino acid of the mature hormone. The use of synthetic DNA also allowed for the design of a new coding sequence for the amino terminal region of the bGH and pGH genes. The amino acid sequences encoded by the synthetic regions of the growth hormone genes were exactly maintained due to the redundancy of the genetic code.
The plasmid containing the bGH cDNA was obtained as described by Miller et al., J. Biol. Chem. 255, 7521 (1980) and was designated pBGH-102. It is equivalent to plasmid BP348 of Miller et al. The nucleotide sequence of bGH mRNA and its corresponding amino acid sequence as predicted by the nucleotide sequence were previously published (Miller, W., et al., loc. cit.). The restriction fragment containing the tryptophan promoter-operator and ribosome binding site sequences were obtained from ptrpL1-R2 and -R4. The sequences of the synthetic double-stranded DNA used to modify the amino and carboxy termini of the growth hormone genes were extracted from the paper by Seeburg et al. (1983, DNA 2; 37-45). The oligonucleotides were synthesized, as noted above, using the phosphoramidite chemistry (Caruthers, et al.) and fragments were assembled from single-stranded oligomers, 11-16 bases long. The N-terminal synthetic DNA encodes the artificial ATG initiation codon for protein synthesis and the first 23 amino acid codons of bGH. To facilitate its insertion into pBR322 DNA, this synthetic fragment also included 4-base single-strand cohesive ends on the 5' ends corresponding in sequence to the cohesive ends generated by restriction endonucleases EcoRI and HindIII. The desired ligation product was isolated from a 5% polyacrylamide gel as a band of approximately 80 bp. The purified DNA was then ligated with pBR322 DNA which had been previously digested with restriction endonucleases EcoRI and HindIII, and transformed into competent E. coli cells. The cloned synthetic DNA was subject to DNA sequence analysis using the chemical degradation method (Maxam and Gilbert, 1980, Methods Enzymol 65; 499) to ensure the integrity of the modified bGH sequence.
Expression vectors similar to the plasmids described by Seeburg et al. were constructed for both bGH and pGH in order to compare the effect of the altered ribosome binding site on the expression of mammalian genes other than prorennin. The experimental steps used for constructing the bGH expression plasmids are illustrated in FIGS. 5 and 6.
First the region from the cDNA clone, pBGH-102, encoding sequences for amino acids 23 to 86, was isolated on a 5% polyacrylamide gel and ligated to the cloned synthetic 75 bp EcoRI-PvuII fragment isolated from the pBR322 subclone which encodes sequences for the ATG initiation codon and the first 22 amino acids of bGH. The ligation mix was cleaved with restriction endonucleases EcoRI and PstI, and a 270 bp fragment was isolated from a 5% polyacrylamide gel and inserted into appropriately cleaved pBR322 DNA. Using these two sites, the EcoRI-PstI DNA fragment of modified bGH gene sequence can be inserted into the pBR322 plasmid so that only one orientation of insertion is possible. Plasmid DNA isolated from transformants obtained in the ligation were cleaved with EcoRI and PstI to verify the insertion of the 270 bp bGH gene fragment into the vector. Next, the 440 bp PstI DNA fragment from pBGH-102 containing the coding sequences of bGH amino acids 91 to 191 (plus the 3' untranslated region of the bGH cDNA) was inserted into the PstI site of this plasmid DNA in order to complete the reconstruction of the full length bGH gene. This PstI fragment could be inserted in two possible orientations relative to the rest of the bGH gene. According to the restriction map, the desired orientation of the insert would generate an approximately 490 bp PvuII fragment (completely internal to the bGH gene) while the wrong orientation would result in a 350 bp PvuII DNA fragment. Multiple isolates of both orientations were identified after cleavage of plasmid DNA from tetracycline-resistant transformants with restriction endonuclease PvuII. One of the plasmids identified in this manner was designated pBGH-212, and this full length bGH gene was further analyzed by restriction mapping and DNA sequencing to ensure the correctness of the plasmid construction.
The next step in the assembly of the bGH expression plasmids involved the insertion of EcoRI DNA fragments containing the E. coli trp promoter and ribosome binding sequences. The full length bGH clone, pBGH-212, was cleaved with restriction endonuclease EcoRI, treated with bacterial alkaline phosphatase, and ligated with two different approximately 390 bp EcoRI fragments containing the sequences required for bacterial expression of bGH. Two different ligations were done to insert the trp promoter-rbs fragments, each with slightly different nucleotide sequences in the gene initiation region, into pBGH-212. Competent cells of strain HB101 were transformed with each ligation reaction mix. Several tetracycline-resistant colonies from each transformation were picked and isolated plasmid DNA was subject to restriction endonuclease digestion analysis. The trp promoter-rbs containing fragment could insert into the pBGH-212 DNA in two possible orientations relative to the direction of transcription from the promoter. The orientation of the promoter-rbs insert which would result in transcription of the bGH gene generates a 60 bp HindIII DNA fragment, while the undesired orientation generates a 400 bp fragment. Multiple recombinant microorganisms from each ligation mix were identified with plasmids bearing the complete bGH gene adjacent to the trp promoter-rbs sequence in the configuration required for direct expression.
The construction of expression plasmids was initiated by isolating an approximately 920 bp HindIII-PvuII(partial) DNA fragment from the plasmids pBGH-212-R2 and pBGH-212-R4. This DNA fragment contains the trp promoter-rbs sequence and almost the entire bGH coding sequence (all but the last 4 amino acid residues and the stop codon). To express the entire hormone, a fragment of synthetic DNA encoding the C-terminal end of bGH was cloned into pBR-322. This 20 bp DNA fragment was synthesized as two separate oligomers, annealed to form a double-stranded fragment, and inserted into pBR322 DNA digested with restriction endonucleases EcoRI and HindIII. After digestion of plasmid DNA from this subclone with restriction endonucleases PvuII and BamHI, a 365 bp PvuII-BamHI DNA fragment was gel isolated and purified by electro-elution. The final expression plasmids were assembled by ligating the cloned synthetic C-terminal containing fragment (365 bp) with each of the trp promoter-rbs-bGH DNA fragment (920 bp) and the pBR322-derived vector fragment (3995 bp), as shown in FIG. 6. The full length bGH expression plasmids were identified by restriction endonuclease cleavage with PvuII. These bGH expression plasmids were further characterized by more precise determination of the restriction enzyme cleavage map. Additional characterization of these expression plasmids by DNA sequencing verified the modified bGH gene sequence and established the separate identity of the two different vectors; designated pBGH-301 and pBGH-375.
Translation of the DNA sequences of these expression plasmids predicts a hormone polypeptide of 191 amino acid residues. The estimated molecular weight of such a protein would be about 22,000. When cells containing the bGH expression plasmids pBGH-301 and pBGH-375 were grown under conditions known to induce trp promoter directed expression, the cells produced a comigrating protein the size of purified bGH protein (obtained from Miles) when total protein extracts were examined on SDS-polyacrylamide gel (Laemmli, U. 1970, Nature 277, 680). This band was not visible in protein extracts from cells containing the vector plasmid pBR322 grown under identical conditions. The bGH levels were estimated by densitometer gel scanning at 579 nm. The cultures containing the expression plasmid with the R2 version of the rbs (pBGH-301) produced bGH at levels of about 20% to 25% of the total cellular protein. Whereas, the cells containing the pBGH-375 expression plasmid with the R4 version of the rbs produced bGH at levels about 5% to 7% of the total cellular protein.
In the case of pGH expression, a scheme analogous to that used for bGH expression was employed. The sequence of the double-stranded DNA used to modify the amino terminal end of the pGH gene was essentially as described by Seeburg et al., (loc. cit.). The experimental steps used for constructing the pGH expression plasmids are illustrated in FIG. 7. First, the region from the cDNA clone (pGH 24) was substituted with the synthetic region of the pGH gene. Because the region coding for amino acid residues 22 and 23 of pGH lacked a PvuII site, the synthetic 5' part of the pGH hybrid gene was joined to the coding sequences derived from the cloned cDNA at an AsuI site which occurs at amino acid codons 16 and 17 in pGH-24. An AsuI site was also incorporated at the same position in the synthetic DNA coding for the amino terminal end of pGH. Due to the presence of additional AsuI sites in the cloned cDNA, the pGH gene was reconstructed from three different DNA fragments.
The 635 bp PstI-PvuII fragment isolated from pGH-24 was digested with RsaI and the resulting 200 bp PstI-RsaI fragment was further cleaved with AsuI. The modified gene was constructed by ligating together the cloned synthetic EcoRI-AsuI 53 bp fragment, the 75 bp AsuI-RsaI fragment, and the 480 bp RsaI-PvuII fragment. The product of this ligation was digested with EcoRI and PvuII, and a DNA fragment corresponding to 570 bp in size was isolated from a 5% polyacrylamide gel. This fragment was ligated with the EcoRI-PvuII (partial) vector fragment from the bGH expression plasmid pBGH-375 and transformed into competent cells of E. coli strain MM294 (ATCC 33625) and selected on plates containing ampicillin. This pre-expression plasmid (identified by the presence of a 910 bp EcoRI-BamHI fragment) contains the full length pGH gene, since the pGH and bGH proteins have the same C-terminal amino acid sequence.
The next step in the construction of the pGH expression plasmids involved the insertion of the approximately 390 bp EcoRI DNA fragments containing the E. coli trp operon promoter sequence and modified ribosome binding sites. The full length pGH plasmid was cleaved with restriction endonuclease EcoRI and ligated with separate versions of the EcoRI fragments containing the sequence needed for bacterial expression of pGH. Two different ligation reactions were made using expression fragments with slightly different nucleotide sequences in the region around the ribosome binding site. Competent cells of strain C600 were transformed with each ligation reaction. Plasmid DNA was isolated from several drug resistant colonies from each transformation and was subjected to restriction endonuclease digestion analyses. The trp promoter containing fragment could insert into the pre-expression plasmid in two possible orientations relative to the direction of transcription from the trp promoter. The orientation of the promoter insert fragment which would result in the transcription of the pGH gene generates a 920 bp HindIII DNA fragment, while the undesired orientation generates a 600 bp DNA fragment. Multiple isolates from each ligation reaction were identified with plasmids bearing the complete pGH gene adjacent to the trp promoter and rbs sequence in the configuration required for direct expression. Further characterization of these expression constructions was achieved by physical mapping with additional restriction endonucleases. Additional characterization of these pGH expression plasmids by DNA sequencing has established their separate identity at the nucleotide level. The two pGH expression plasmids were designated pGH-101 and pGH-107.
Translation of the DNA sequence of these pGH expression plasmids predicts a hormone polypeptide of 191 amino acids. The estimated molecular weight of such a protein would be about 22,000. When recombinant microorganisms comprising plasmids pGH-101 or pGH-107 were grown under conditions known to induce trp promoter directed expression, the cells produced a protein with a size of about 22,000 daltons. This band was absent from protein extracts prepared from cells containing the vector plasmid pBR322 grown under identical conditions. The level of pGH production was determined using densitometer scans of individual lanes of SDS-polyacrylamide gels. Several E. coli proteins fall into the 22,000 dalton size range and constitute about 2% to 5% of the total cell protein in control cell extracts. Correcting for the contribution of these native proteins, the pGH bands visible in the expression culture protein extract represent about 5% and 15% of the total cell protein for pGH-101 and pGH-107, respectively. The quantitation of pGH levels in cultures grown in the presence of tryptophan (100 μg/ml) showed reduced levels of pGH expression. This fact would imply that production in E. coli of the pGH protein was indeed under control of the trp promoter-operator as designed. The difference in expression levels in the case of pGH was similar to that observed in prorennin and bGH expression using the same ribosome binding site sequence.
Another example of efficient expression of a heterologous gene using the "R2" trp promoter-rbs is the production of human urogastrone or epidermal growth factor (hEGF) from a synthetic DNA sequence. The plan devised to achieve efficient bacterial production of hEGF employed the chemical construction of a DNA fragment containing the coding sequence of mature hEGF. This approach allowed for the direct expression of the mature hormone by introducing an ATG initiation codon for protein synthesis in front of the codon coding for the first amino acid residue of the mature EGF polypeptide. The synthetic gene is composed of 15 oligonucleotides, 12 to 45 bases in length. Three separate ligations were performed and the intermediate ligation products were isolated on a polyacrylamide gel. The purified intermediate ligation products were then ligated in the final assembly of the hEGF gene. To facilitate its insertion into plasmid pBR322 DNA, the synthetic hEGF gene was designed to contain EcoRI and HindIII restriction endonuclease cohesive ends at its termini. The hEGF synthetic DNA was ligated with pBR322 DNA cleaved with EcoRI and HindIII and the synthetically derived region of the plasmid was analyzed by DNA sequencing (Maxam and Gilbert, loc. cit.) to ensure correctness.
Vectors for the expression of hEGF in E. coli were constructed using the trp promoter-rbs fragment previously used for high level expression of prorennin, bGH, and pGH. The construction of the EGF expression plasmids was initiated by cleavage of the pBR322-EGF subclone with the restriction endonuclease EcoRI and subsequent dephosphorylation with bacterial alkaline phosphatase. The expression plasmids were constructed using the EcoRI fragments containing the trp promoter-rbs sequence. Two different ligations were done employing the trp promoter-rbs fragments with slightly different nucleotide sequences in the region around the ribosome binding site. Competent cells of E. coli strain HB101 were transformed with each ligation reaction. Several drug resistant colonies from each transformation were picked and isolated plasmid DNA was subject to restriction endonuclease cleavage analysis. The trp promoter-rbs containing fragment could be inserted into the EGF subclone in two possible orientations relative to the direction of transcription from the promoter. The orientation of the promoter insert fragment which would result in expression of the synthetic EGF gene generates a 510 bp HindIII DNA fragment, whereas the undesired orientation generates a 200 bp HindIII DNA fragment. Multiple isolates from each ligation reaction were identified with plasmids bearing the EGF gene adjacent to the bacterial promoter-rbs sequence in the configuration required for direct expression. DNA sequence analysis of the expression plasmids confirmed that the EGF coding sequence directly follows the E. coli trp promoter-rbs as desired. The ATG initiation codon follows the ribosome binding site sequence by 5 and 11 nucleotides in the EGF expression plasmids designated pEGF-R2 and PEGF-R4, respectively.
Translation of the DNA sequence of the EGF expression plasmids predicts a 54 amino acid poly-peptide containing six cysteine residues, which are thought to form three intrachain disulphide bonds. The estimated molecular weight of such a hormone would be about 6,353. Cultures of a mutant strain of E. coli designated as lon (Gottesman et al., J. Bacteriol. 148, 265, 1981), available from the E. coli Genetic Stock Center, Yale University, New Haven, Conn., as strain No. ECGSC-6436, were transformed with EGF expression plasmids and grown under conditions known to induce trp promoter directed expression. This mutant strain, which lacks one of several proteases present in wild-type cells, was used to minimize proteolysis of the bacterially produced hEGF.
Total protein extracts of these expression cultures were examined on 15% SDS-polyacrylamide gels in an effort to determine the level of EGF production. Although there was relatively poor resolution of the low molecular weight polypeptides (including purified mouse-EGF obtained from a commercial source), there appeared to be more protein in the EGF molecular weight range in the extracts from expression cultures compared to control extracts. Densitometer scans of individual lanes of the SDS-polyacrylamide gel were run. Cellular proteins less than 10,000 daltons in size constitute about one percent of the total cellular protein in control extracts. Correcting for the contribution of these native proteins, the putative EGF levels in the expression culture protein extracts corresponds to about 3 to 5 percent of the total cellular protein. | Promoter-ribosome binding site (rbs) expression elements of general utility for high level heterologous gene expression; plasmids carrying said promoter-rbs expression elements and encoding genetic information for direct high level expression in bacteria of heterologous proteins, especially plasmids carrying a gene coding for prorennin or mammalian growth hormones; methods for their construction, including the use of synthetic linkers to provide desirable functional properties thereto; recombinant microorganisms comprising said plasmids; expression of said bacterial produced heterologous proteins by said recombinant microorganisms; and demonstration of the activities of the thus-produced proteins. | 2 |
TECHNICAL FIELD
This invention relates to a novel method for the synthesis of 6-iodo-2-oxindole useful as intermediate in the manufacture of pharmaceutically active ingredients.
BACKGROUND
6-iodo-2-oxindole is an important intermediate for the production of pharmaceutically active ingredients. The synthesis of this intermediate has been described in the literature before and is quite challenging. Therefore there is a strong demand for efficient methods to manufacture 6-iodo-2-oxindole in the high quality needed for pharmaceutical intermediates.
In current literature several routes to manufacture 6-iodo-2-oxindole have been described.
WO 2007008985 describes the synthesis of 6-iodo-2-oxindole via catalytic electrophilic aromatic iodination of 6-bromo-2-oxindole using sodium iodide in the presence of a copper catalyst (Scheme 1). The disadvantage of this approach is the fact that 6-bromo-2-oxindole is not directly commercially available as a bulk chemical. Additionally the use of large amounts of a copper catalyst, the use of dioxane as solvent and several reaction additives which are only available on laboratory scale disqualify this approach for commercial production.
JP 2011207859 describes the synthesis of 6-iodo-2-oxindole from 1,4-diiodo-2-nitro-benzene via two steps of reaction. The disadvantage of this process is again the use of a starting material that is not commercially available on larger scale, therefore this process is also disqualified for use for commercial production of 6-iodo-2-oxindole (Scheme 2).
Therefore there is a strong need for a novel process to manufacture 6-iodo-2-oxindole, which allows to use commercially available bulk chemicals as starting materials and which renders the desired product in high quality and good chemical yield.
DESCRIPTION OF THE INVENTION
The present invention provides an efficient process for the manufacture of 6-iodo-2-oxindole in high quality starting from commercially available 2-chloro-nitrobenzene as starting material in the steps as described herein below.
It has been found that the very cheap starting material 2-chloro-nitrobenzene, after selective iodination to 2-chloro-5-iodonitrobenzene could be used in this reaction, whereas the process described in JP 2011207859 (Scheme 2) shows the use of rather instable 2,5-diiodonitrobenzene is necessary for the successful application of the follow-up steps. Within the present invention it has been shown, that the more stable and easier to produce intermediate 2-chloro-5-iodonitrobenzene can be successfully used in the downstream steps, for example alkylation with a malonic acid dialkyl ester (preferably dimethylmalonate or diethylmalonate) and successively be transformed to 6-iodo-2-oxindole in very high purity.
Thus, the present invention relates to a process for preparing 6-iodo-2-oxindole comprising:
a) iodination of 2-chloro-nitrobenzene to form 2-chloro-5-iodonitrobenzene, b) reacting 2-chloro-5-iodonitrobenzene with malonic acid dialkyl ester, preferably malonic acid dimethyl ester (dimethylmalonate) or malonic acid diethyl ester (diethylmalonate), to form 2-(4-iodo-2-nitrobenzene)-dialkylymalonate, and c) performing a reduction, cyclisation and decarboxylation to form 6-iodo-2-oxindole.
A general process for preparing 6-iodo-2-oxindole is outlined in Scheme 3a. In one embodiment, the present invention is directed to the general multi-step synthetic method for preparing 6-iodo-2-oxindole as set forth in Scheme 3a below. In other embodiments, the invention is directed to each of the individual steps of Scheme 3a and any combination of two or more successive steps of Scheme 3a. The invention may also be directed to the intermediate compounds, e.g. as set forth in Scheme 3a.
In certain more detailed embodiments of the invention, the present invention relates to the process and/or the individual process steps substantially as disclosed according to following Scheme 3b:
In the first step of the process according to the present invention, 2-chloro-nitrobenzene is oxidatively iodinated to form 2-chloro-5-iodonitrobenzene (Compound A) by using a suitable iodination agent, for example a mixture of molecular iodine and sodium periodate, preferably in the presence of a suitable acid (such as e.g. (concentrated) sulfuric acid) and preferably in a suitable solvent (such as e.g. a mixture of (glacial) acetic acid and acetic anhydride). Preferably the iodination reaction is carried out at elevated temperature.
In the second step, 2-chloro-5-iodonitrobenzene (Compound A) is selectively alkylated with for example a malonic acid dialkyl ester, preferably dimethyl malonate or diethylamlonate, in a nucleophilic substitution reaction to form the intermediate 2-(4-iodo-2-nitrobenzene)-dialkylmalonate, preferably 2-(4-iodo-2-nitrobenzene)-dimethylmalonate or -diethylmalonate (Compound B), preferably by using standard basic conditions (such as e.g. suitable metal alkanolate, e.g. sodium alkanolate, such as e.g. sodium methanolate or sodium ethanolate as base) and in a suitable solvent (such as e.g. N,N-dimethylacetamide, DMAc). Preferably the alklyation reaction is carried out from reduced to elevated temperature. Preferably, the choice of the appropriate metal alkanolate (particularly sodium alkanolate) may be based on the choice of the respective alkyl ester.
In the next step(s), 2-(4-iodo-2-nitrobenzene)-dialkylmalonate (Compound B) is treated under reductive, cyclisative and decarboxylative conditions. For example, using a suitable reducing agent, such as e.g. a tin(II)-based reducing agent (preferably SnCl 2 ), or Fe in acidic media, catalytic hydrogenation, or the like, in a suitable solvent (such as e.g. ethanol), preferably followed by further steps (which may be in any order) comprising cyclization, decarboxylation, and, optionally if required, further reduction of the resulting intermediate(s) or mixture of intermediates, to yield 6-iodo-2-oxindol. The resulting intermediate(s) or mixture of intermediates obtained from the steps above may be repeatedly treated under suitable conditions to induce full cyclisation, reduction and decarboxylation to form 6-iodo-2-oxindole. The cyclization and/or decarboxylation is preferably conducted under acid conditions (such as e.g. using aqueous HCl) in a suitable solvent (such as e.g. aqueous ethanol). Preferably the reduction reaction and/or the cyclization and/or the decarboxylation reaction are carried out at elevated temperature.
Optionally, the last steps (reduction/cyclization/decarboxylation) described above can be run without the necessity to isolate the corresponding intermediates, for example 1-hydroxy-6-iodo-2-oxo-2,3-dihydro-1H-indole-3-carboxylic acid alkyl (e.g. methyl or ethyl) ester, so the intermediates can be handled in solution e.g. to reduce operation complexity.
Further, optionally, the second and third steps described above can be run without the necessity to isolate the resulting intermediate, 2-(4-iodo-2-nitrobenzene)-dialkylmalonate, so also this intermediate can be handled in solution e.g. to reduce operation complexity.
In a further alternative, optionally, even the steps described in the second step and the in the last steps together, can be run without the necessity to isolate the corresponding intermediates, so also these intermediates can be handled in solutions to reduce operation complexity.
In particular embodimental aspects of the invention, reference may be made to the following aspects 1-22 according to the invention:
1. A method of preparing a compound of formula (B)
wherein R and R′ may be the same or different, and are each independently selected from C 1-4 -alkyl (e.g. methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, or tert-butyl), particularly C 1-2 -alkyl such as methyl or ethyl,
or R and R′ together are a —CH 2 —, —CH 2 CH 2 — or —C(CH 3 ) 2 — group,
preferably R and R′ are the same and are each methyl or ethyl,
said method comprising reacting 2-chloro-5-iodonitrobenzene having the formula (A)
with an open chain or cyclic malonic acid dialkyl ester of formula
wherein R and R′ are defined as in formula (B), preferably in the presence of a suitable base, to form a compound of formula (B).
2. The method according to aspect 1, wherein a suitable base is sodium methanolate or sodium ethanolate.
3. The method according to aspect 1 or 2, wherein the reaction is conducted in a suitable solvent or mixture of solvents, preferably comprising N,N-dimethylacetamide.
4. A method of preparing a 6-iodo-2-oxindole having the formula
said method preferably comprising the method according to aspect 1, 2 or 3, and further comprising a) reducing a compound of formula (B), preferably in the presence of a suitable reducing agent; and b) cyclizing, optionally further reducing and decarboxylating the resulting intermediates or mixture of intermediates, preferably in the presence of a suitable acid, to form 6-iodo-2-oxindole.
5. The method according to aspect 4, wherein a suitable reducing agent preferably in a) is a tin(II)-based reducing agent (preferably SnCl 2 ).
6. The method according to aspect 4 or 5, wherein the reduction reaction in a) is conducted in a suitable solvent or mixture of solvents, preferably comprising ethanol.
7. The method according to aspect 4, wherein a suitable acid in b) is aqueous HCl.
8. The method according to aspect 4 or 7, wherein the cyclization and/or decarboxylation and/or optional further reduction reaction in b) is conducted in a suitable solvent or mixture of solvents, preferably comprising ethanol.
9. The method according to any one of aspects 1 to 8, wherein the intermediate compound of formula (B) is either (in one embodiment) isolated or (in another embodiment) not isolated.
10. The method according to any one of aspects 4 to 8, wherein an intermediate compound obtained from step a) of aspect 4 is either (in one embodiment) isolated or (in another embodiment) not isolated.
11. The method according to any one of aspects 4 to 8, wherein an intermediate compound obtained from any reactions of step b) of aspect 4 is either (in one embodiment) isolated or (in another embodiment) not isolated.
12. The method according to any one of aspects 1 to 8, wherein the intermediate compound of formula (B) and/or an intermediate compound obtained from step a) of aspect 4 and/or an intermediate compound obtained from any reactions of step b) of aspect 4 is/are either (in one embodiment) isolated or (in another embodiment) not isolated.
13. The method according to any one of aspects 1 to 12, wherein R and R′ are the same and are preferably methyl or ethyl.
14. The method according to any one of aspects 1 to 13, wherein the compound of formula (A) is prepared by iodination of 2-chloro-nitrobenzene.
15. The method according to aspect 14, wherein the system I 2 /NalO 4 preferably in the presence of a suitable acid (e.g. sulfuric acid) is used for iodination.
16. The method according to aspect 14 or 15, wherein the reaction is conducted in a suitable solvent or mixture of solvents, preferably comprising acetic acid and acetic anhydride.
17. A compound of formula
for example either in isolated form or in solution.
18. A compound of formula
wherein R, R′ is as defined above (e.g. methyl or ethyl), for example either in isolated form or in solution.
19. A method of preparing a 6-iodo-2-oxindole having the formula
said method preferably comprising the method according to aspect 1, 2, 3, 4a or 4b (cyclizing), and further comprising
reducing and/or decarboxylating a compound of formula
wherein R, R′ is as defined above,
preferably in the presence of a suitable reducing agent (e.g. SnCl 2 ) and/or preferably in the presence of a suitable acid (e.g. HCl), preferably in a suitable solvent or mixture of solvents, preferably comprising ethanol, to form 6-iodo-2-oxindole.
20. A method of preparing a 6-iodo-2-oxindole having the formula
said method preferably comprising the method according to aspect 1, 2, 3, 4a or 4b (cyclizing), and further comprising
decarboxylating a compound of formula
wherein R, R′ is as defined above,
preferably in the presence of a suitable acid (e.g. HCl), preferably in a suitable solvent or mixture of solvents, preferably comprising ethanol, to form a compound of formula
and
reducing the obtained 1N-hydroxy-6-iodo-2-oxindole to form 6-iodo-2-oxindole,
preferably in the presence of a suitable reducing agent, preferably in a suitable solvent or mixture of solvents, preferably comprising ethanol, to form 6-iodo-2-oxindole.
21. A method of preparing a 6-iodo-2-oxindole having the formula
said method preferably comprising the method according to aspect 1, 2, 3, 4a or 4b (cyclizing, decarboxylating), and further comprising
reducing a compound of formula
preferably in the presence of a suitable reducing agent and preferably in the presence of a suitable acid, preferably in a suitable solvent or mixture of solvents, preferably comprising ethanol, to form 6-iodo-2-oxindole.
22. A compound of formula
for example either in isolated form or in solution.
The reactants used in the synthetic schemes described below may be obtained either as described herein, or if not described herein, are themselves either commercially available or may be prepared from commercially available materials by methods known in the art.
Optimum reaction conditions and reaction times may vary depending on the particular reactants used. Unless otherwise specified, solvents, temperatures, pressures, and other reaction conditions may be readily selected by one of ordinary skill in the art. Specific procedures are provided in the Synthetic Examples section. Typically, reaction progress may be monitored by High Pressure Liquid Chromatography (HPLC) or Thin Layer Chromatography, if desired.
EXAMPLES
In order that this invention be more fully understood, the following examples are set forth. These examples are for the purpose of illustrating preferred embodiments of this invention, and are not to be construed as limiting the scope of the invention in any way. All commercial products are bought from SCRC, except sodium methylate and sodium ethylate which are from Acros.
Exemplary HPLC method (UV length: 254 nm): The separation is performed on an Xbridge™ C18 3.5 μm 4.6×100 mm, Waters at a column temperature of 30° C. A mixture of Water with 0.1% formic acid (pH 2.7) and 100% acetonitrie is used as mobile phase (80/20-30/70). The method run time is set at 20 min applying a mobile phase flow rate of 1.0 mL/min. The injection volume is 1.0 μL.
Preparation of 2-chloro-5-iodonitrobenzene
To a jacketed reactor, acetic acid (450 mL) and acetic anhydride (225 mL) is charged at 10° C. Then, to the above mixture, NalO 4 powder (97.2 g) and Iodine (77.2 g) is added under stirring. While keep internal temperature at below 30° C., conc. H 2 SO 4 (720 mL) is added dropwise. Then, 2-chloro-nitrobenzene (Rt=11.11 min) is added in one portion, and heat the mixture gradually to 64° C. The resulting mixture continues to be stirred for usually at least 2 hours until process monitor shows almost complete conversion. Then, the mixture is cooled down to room temperature, and transferred slowly into another jacketed reactor with pre-cooled cold Na 2 SO 3 solution (250 g Na 2 SO 3 in 2000 mL water). Collect the wet cake by filtration and wash the cake with water (450 mL×2), then purification of the cake with n-heptane crystallization to afford 2-chloro-5-iodonitrobenzene in 62% yield and 98% HPLC purity (Rt=15.75 min).
1 H NMR (400 MHz, CDCl 3 ) δ 7.26-7.29 (m, 1H), 7.81-7.84 (dd, J=8.4, 2.0 Hz, 1H), 8.17-8.16 (d, J=2.0 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 90.5, 127.0, 133.2, 134.1, 142.1, 148.3; MS (ESI): m/z 282.9 (M).
Preparation of 2-(4-iodo-2-nitrobenzene)-dimethlymalonate
To a jacketed reactor, N,N-dimethylacetamide (DMAc) (960 mL) and sodium methylate (NaOMe) powder (77.8 g) is charged at 20° C. Dimethyl malonate (191 g) is added dropwise into the above mixture while keeping internal temperature at around 10° C. After finishing addition, warm up the mixture to 20° C., and continue to stir for another 10 minutes. Then, 2-chloro-5-iodonitrobenzene (136 g) is added in one portion, and heat the mixture to 78° C. and stir for usually at least 2.5 hours until process monitor shows almost complete conversion. The resulting mixture is cooled down to 20° C., and it is quenched by 2 N cold aq. HCl solution (1440 mL). Then, the mixture is stirred for another 1 hour. Collect the solid by filtration and wash the solid with water (500 mL) to afford 2-(4-iodo-2-nitrobenzene)-dimethlymalonate (146 g) as pale yellow solid in 80% yield and 97% HPLC purity (Rt=13.9 min).
1 H NMR (400 MHz, CDCl 3 ) δ 3.79 (s, 6H), 5.26 (s, 1H), 7.25-7.27 (m, 1H), 7.95-7.98 (dd, J=8.3, 1.8 Hz, 1H), 8.36-8.37 (d, J=1.8 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 53.3, 53.6, 93.4, 127.4, 132.8, 133.8, 142.4, 148.9, 167.1; MS (ESI): m/z 378.96 (M+1).
Preparation of 6-iodo-2-oxindole
To a jacketed reactor, 2-(4-iodo-2-nitrobenzene)-dimethlymalonate (130 g) is charged at 20° C., followed by ethanol (600 mL). Then, to the above solution the first portion of SnCl 2 .2H 2 O (193.5 g) powder is added, and the resulting mixture is heated to 70° C. and stirred for 1 hour. The second portion of SnCl 2 .2H 2 O (193.5 g) is added, the mixture is stirred usually at least 0.5 hour until process monitor shows almost complete conversion. Then, heat the resulting mixture to 80° C. and add 36% aq. HCl solution (360 mL) during 0.5 hour. The mixture is stirred for at least 2.5 hours until process monitor shows almost complete conversion. Then, to the mixture water (550 mL) is added and the resulting mixture is cooled down to 20° C. Collect the solid by filtration and wash the solid with water (500 mL) to afford the crude 6-iodo-2-oxindole. Then, it is purified by crystallization with acetic acid (HOAc) (560 mL), and followed by washing with 3 N aq. HCl solution (480 mL) to afford the 6-iodo-2-oxindole in 62% yield and 99% HPLC purity (Rt=7.45 min).
1 H NMR (400 MHz, DMSO) δ 10.42 (5, 1H), 7.29-7.27 (dd, J=8.0, 1.6 Hz, 1H,), 7.11 (d, J=1.6 Hz, 1H), 7.02-7.00 (d, J=8.0 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 175.9, 145.3, 129.6, 126.4, 125.7, 117.4, 92.2, 35.4; MS (ESI): m/z 260.1 (M+1).
Preparation of 6-iodo-2-oxindole from 2-chloro-5-iodonitrobenzene and diethyl malonate without Isolation of Intermediates
To a jacketed reactor, N,N-dimethylacetamide (DMAc) (120 mL) and sodium ethylate (NaOEt) powder (12.1 g) is charged at 20° C. Diethylmalonate (28.8 g) is added dropwise into the above mixture while keeping internal temperature at around 10° C. After finishing addition, warm up the mixture to 20° C., and continue to stir for another 10 minutes. Then, 2-chloro-5-iodonitrobenzene (17 g) is added in one portion, and heat the mixture to 78° C. and stir for usually at least 2.5 hours until process monitor shows almost complete conversion. The resulting mixture is cooled down to 20° C., and it is quenched by 2 N cold aq. HCl solution (180 mL). The bottom yellow oil was transferred to a jacket reactor with ethanol (92 mL) in it. Then, to the above solution the first portion of SnCl 2 .2H 2 O (30 g) powder is added, and the resulting mixture is heated to 70° C. and stirred for 1 hour. The second portion of SnCl 2 .2H 2 O (30 g) is added, the mixture is stirred usually at least 0.5 hour until process monitor shows almost complete conversion. Then, heat the resulting mixture to 80° C. and add 36% aq. HCl solution (60 mL) during 0.5 hour. The mixture is stirred for at least 2.5 hours until process monitor shows almost complete conversion. Then, to the mixture water (90 mL) is added and the resulting mixture is cooled down to 20° C. Collect the solid by filtration and wash the solid with water (250 mL) to afford the crude 6-iodo-2-oxindole. Then, it is purified by crystallization with acetic acid (HOAc) (110 mL), and followed by washing with 3 N aq. HCl solution (80 mL) to afford the 6-iodo-2-oxindole in 53% yield and 99% HPLC purity (Rt=7.45 min).
1 H NMR (400 MHz, DMSO) δ10.42 (S, 1H), 7.29-7.27 (dd, J=8.0, 1.6 Hz, 1H,), 7.11 (d, J=1.6 Hz, 1H), 7.02-7.00 (d, J=8.0 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 175.9, 145.3, 129.6, 126.4, 125.7, 117.4, 92.2, 35.4; MS (ESI): m/z 260.1 (M+1). | Disclosed is a method for the synthesis of 6-iodo-2-oxindole useful as intermediate in the manufacture of pharmaceutically active ingredients. Also disclosed is a novel intermediate used in the synthesis of this compound. | 2 |
This invention relates to urinary catheters, and in particular to a method and apparatus for a pressure-activated, magnetic-force-controlled human (or animal) bladder drainage cycling valve system(Uro Cycler), for restoring normal body functions of bladder filling and emptying in cyclic manners of catheterized patients, and this invention claims the benefit of priority to U.S. Provisional Application No. 60/280,767, filed Apr. 2, 2001, U.S. Provisional Application No. 60/280,768 filed Apr. 2, 2001, and U.S. Provisional Application No. 60/324,601 filed Sep. 25, 2001.
BACKGROUND AND PRIOR ART
Urinary catheters bypass the normal bladder process of storing urine, and only releasing the urine by using the bladder detrusor muscle. Catheters can be a necessary tool to open the bladder to allow urination when patients have trouble urinating. A catheter can be a lifesaving tool since an uncontrolled buildup of urine can cause serious medical problems including death. However, there are known problems with catheters.
Struvite crystal encrustation is the effect of stagnated urine in the neck of the bladder when using a catheter. In the face of an indwelling catheter, urine can pool at the neck of the bladder, and the pooled urine can shift from a normal pH factor to an abnormal pH level of 10 or more while it stagnates. Urine shifts to an ammonia state where struvite crystals can precipitate and enlarge on the indwelling catheter. This situation can occur as the bladder loses its natural ability to cyclically flush itself in the face of an indwelling catheter. Bladder wall thickening has also be observed in long-term catheterizations and may be a result of the increasing pH levels.
Urinary tract infections can occur as the urine stagnates and shifts from its normal, acidic antibiotic property through the pH spectrum. Pooled urine that can occur in the neck of the bladder beneath the indwelling catheter can be a natural breeding ground for microbes which can migrate in the body.
Bladder spasms can also occur with an indwelling catheter which causes the bladder to cease its normal cycle of filling and flushing. A dynamic functioning system is converted to a static state with a catheter, and painful bladder spasms can occur. Bladder atone can also occur where short term or more permanent loss of natural bladder functions occurs by using a catheter.
It is also generally well known in medical circles that a human bodies primary defense mechanism against urinary track infections and the other problems listed above is the process known as “wash-out”, where it is advantageous to allow a bladder to normally fill up and be released at one time rather than in an uncontrolled drip fashion that would occur with using a catheter.
Various catheter type instruments and procedures have been used for draining bladders of patients in hospitals. These instruments and procedures have evolved from constant (non-cycling) drip drainage through painfully inserted catheters by siphoning, suction and various types of awkward manually externally controlled cycling apparatus and procedures. Fundamental to an effective, safe, and appropriate device and method is allowing the bladder to fill reasonably and then draining it without a suction pump and without allowing build-up or entry of infectious contaminants in the drainage system.
Included in previous methods and devices have been U.S Pat. Nos. 2,602,448 and 2,860,636 which utilized a siphon in combination with a reservoir to provide cyclic draining of the bladder. Pressure release in these devices is controlled by raising the height of the device on a bedside tree. It is subject to distortion by shifting and turning of the patient and is unreliable (and can compromise safety) besides restricting the patient.
U.S. Pat. No. 3,598,124, describes a siphon leg controlled by merely attaching a catheter to a bedside tree at predetermined adjusted height, which varies the pressure at which the bladder will drain and provides a flutter valve near the patient to break the siphon action of the system once the bladder has drained.
U.S. Pat. No. 4,230,102, describes a device for the draining of a bladder in which a T-joint has been placed on a catheter and has a pressure membrane attached thereto in a large casing for actuating a pressure switch which in turn actuates an electric motor driving a gear train and cam. A cam follower is spring loaded to clamp the catheter for two minute cycles upon actuation by the pressure switch to drain the bladder. However, this type of device, can be expensive and bulky and positions an electrical apparatus adjacent to the catheter.
U.S. Pat. No. 4,424,058, describes a spring-return valve in conjunction with a siphon-release orifice to prevent excessive suction and to prevent urine from remaining in the system after drainage. A problem with this system was that the restoring force of the spring increased with distance of travel from a closed position. This valve was very unsatisfactory because it closed again as soon as the urine fluid pressure dropped off, thus causing fluid to remain trapped in the bladder to stagnate with further elapsed time. Only a full bladder would open it, sometimes at an uncomfortably high (and potentially unsafe) pressure, and only a relatively full bladder would keep it open to allow complete drainage unless overridden by the patient bearing down heavily on the lower abdomen. Also, positioning of tubes leading from it was parallel to the leg on which it was attached and provided a situation for retention of fluid in the system.
None of the proposed patented devices and techniques described above solves all the problems with catheters that are listed above.
Unlike the problem methods and devices of the prior art, the subject invention provides both consistent magnetic opening and closing of a valve seal with decreased rather than increased closing pressure when opened. As the bladder is emptied, decreasing head pressure against the valve can keep the valve open to establish complete and sterile drainage. In addition, the successfully-tested clinical embodiment of this invention provides simple and convenient manual override, when desired, to decrease or eliminate totally the magnetic closing pressure of the valve.
SUMMARY OF THE INVENTION
A primary objective of the invention is to provide a low pressure magnetic valve for bladder management cyclic flow control having consistent opening and closing of the valve seal with decreasing head pressure against the valve as opposed to increasing pressure. As long as any fluid is coming through the line, the valve will remain open until a complete emptying of the bladder is achieved.
A secondary objective of the invention is to provide a low pressure magnetic valve for bladder management cyclic flow control that establishes complete and sterile drainage as the bladder is being emptied.
A third objective of the invention is to provide a low pressure magnetic valve for bladder management cyclic flow control that can be automatically run with a simple and convenient manual override that can be selectively engaged.
A fourth objective of the invention is to provide a low pressure magnetic valve for bladder management cyclic flow control that helps restore normal body functions of bladder filling and emptying in a cyclic manner, with normal, healthy pressure sensations in spite of the presence of the catheter which typically inhibits “natural” bladder drainage.
The fifth objective of the invention is to provide a low pressure magnetic valve for bladder management cyclic flow control for use with a catheter which can reduce and eliminate known problems that occur with using a catheter such as urinary tract infections, struvite crystal encrustation, bladder spasms and bladder atone.
The sixth objective of the invention is to allow a user wearing a catheter to use their bladder detrusor muscle to selectively turn on a valve in the catheter and complete an entire urination emptying cycle of their bladder.
The invention provides for both consistent magnetic opening and closing of a valve seal with decreased rather than increased closing pressure when being opened. As the bladder is being emptied, the decreasing of head pressure against the valve can keep the valve open to establish a complete and sterile drainage.
In the invention, valve-closing pressure can decrease as a result of three important factors: (1) magnetic pull of a valve decreases as its open distance from magnetic attraction in the direction of the valve seat increases, (2) the gravity-enhanced fluid flow column in the drain down tube provides a slight negative pressure on the back side of the movable magnet (thus tending to hold the valve open until the drain tube empties completely), and (3) fluid passing through the system provides a partial mass flow insulation which tends to hold the moving magnet away from the fixed magnet, also decreasing the net magnetic attraction between the magnetic members. A small amount of air is allowed to leak through a micro-pore filter (which keeps out harmful micro-organisms from the closed system) in order to vent the down line for clean, dry emptying.
The very low-pressure valve system of the invention for use in controlling the flow of most fluids utilizes magnetic forces to hold a smooth surface against an ultra low-durometer (soft) composite seal or valve seat material until such time as the fluid head pressure causes the magnets to separate and the valve to open, at a preset value, to allow maximum fluid flow rate and complete drainage of the system
The use method described here is medical in nature, applying to bladder drainage of catheterized patients into a urine collection bag, as needed, in a normal, cyclic fashion. In other words, head pressure of urine building up in volume against the detrusor muscle of a bladder and in a catheter running from the bladder to the valve where it is positioned on a patient's leg or rests on the bed sheet, causes the valve to open away from the valve-port seat. When the valve is opened, distance increases between the valve magnetic member and a member to which it is magnetically attracted in the direction of the valve-port wall, thereby allowing the valve to remain open with less pressure than that initially required to open it. Fluid passing between the open valve and the member to which it is attracted magnetically decreases further still the closing pressure to offset the head-pressure opening of the valve.
Downstream from the valve, there is a siphon-release air-inlet orifice that relieves siphon (negative pressure) to avoid siphon suction that would either cause collapse of the bladder walls or cause the valve to remain open after the bladder is emptied. An air inlet, allowing only air flow through a micro-pore filter material to the siphon-release orifice, is positioned upstream and radially outward from an outlet to the valve in order to prevent passage of fluid from the valve where siphon pressure does not provide sufficient inward suction of air. The siphon-release orifice is provided with an antiseptic strainer (anti-bacterial/anti-viral filter) and can serve as a low-pressure one-way inlet valve.
The entire valve system (in the embodiment of a small, streamlined, compact, integrated and durable device) also serves as an anti-reflux valve between the patient and the urine collection bag, thus preventing drained (and possibly old and unsterile, septic, contaminated) urine from ever re-entering the catheter, urethra, and bladder of the patient, and potentially causing infection or other problems.
Additional embodiments of this invention provide for a manual override of the valve by selective distancing an externally positioned magnetic member from the valve member that is attracted to it. The override gives flexibility of pressure adjustment and provides the opportunity of assuring full drainage when desired by either physician or the patient. This could manifest itself, in the event of excessive discharge of viscous matter or other mode of lumen blockage, as a “safety” valve to relieve fluid pressure buildup.
An additional swivelable attachment of the bladder cycler to a strap on a patient's leg can allow the cycler to be positioned comfortably at a slant with the outlet and tubes leading from it downward from the valve to further assure that fluid will not remain in the system between drainage cycles whether used in either a prone or vertical position of the leg. The patient also can more readily move about and not be confined or attached to the bed as long as the collection bag is kept attached for use as needed.
The invention can be used as a hospital instrument whenever an indwelling catheter is required, or in clinics, or in physician's offices, or in homes for draining urine from bladders of patients automatically and safely after normal filling, thoroughly and antiseptically. This use is in strong contrast to the typical, non-cyclical, continuous drip associated with urethral catheter drainage into a collection bag. The use of the UroCycler with catheterized patients helps restore the more normal body function of bladder filling and emptying in a cyclic manner, with normal, healthy pressure sensations in spite of the presence of the catheter which here-to-fore prevented “natural” bladder drainage.
Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments which are illustrated schematically in the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of a fully assembled, automatic drainage embodiment.
FIG. 2 is an exploded perspective view showing the components comprising this passive magnetic bladder-cycling valve.
FIG. 3 is a cutaway of the assembly showing the valve in the closed configuration
FIG. 4 is a cutaway of the assembly with the valve open.
FIG. 5 is a section view of the assembly showing the valve closed.
FIGS. 6A and 6B shows an added over-pressure safety release plug embodiment.
FIG. 7A is a section view of assembly with the valve open.
FIG. 7B is an enlarged view of an optional screw with magnet that can alter valve opening pressure.
FIGS. 8A, 8 B, 8 C, and 8 D show embodiments of valve seal and valve seat combinations and useful configurations.
FIGS. 9A, 9 B, 9 C and 9 D shows a fluid pressure and flow time chart showing the invention system operation.
FIG. 10 illustrates the bladder cycler being used with a connected clinician's (or physician's) self-sealing sampling port on the inlet end and a hydrodynamically-balanced outlet downline to a fluid collection bag on the outlet end.
FIG. 11 is a side view of a patient's leg with the invention strapped to it.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
FIG. 1 is a perspective view of the fully assembled bladder cycling passive magnetic valve invention 1 . FIG. 2 is an exploded view of the internal components of the invention 1 of FIG. 1 . Referring to FIGS. 1 and 2, this exploded view shows the key components comprising the assembly. The inlet end, or upper non-magnetic housing 2 has female socket end 2 . 2 which mates with the male prong end 3 . 2 of outlet end, or lower housing non-magnetic 3 , with a water-tight and air-tight bond. A moving magnetic valve member 8 is magnetically attracted in the direction of valve-port wall 4 where the resilient valve seal 9 contacts the valve seat at the outlet end of valve insert orifice 4 . The moving magnetic valve member 8 is attracted magnetically to the valve-port wall 4 due to the fixed upstream magnetic member 7 . Inwardly protruding rails 3 . 6 in lower housing 3 form an internal chamber for allowing the moving magnet valve 8 to slide back and forth. Fixed magnetic member 7 is held in place by prongs 4 . 6 extending from wall 4 having openings/slots 4 . 3 therebetween. The openings/slots 4 . 3 are large enough to allow for fluid flow around the fixed magnetic member 7 . Magnetic attraction can be provided by composition of either or both the moving valve member and the upstream magnetic member. Optionally and preferably, the magnetic valve member 8 and the upstream magnetic member 7 both are inert, ceramic permanent magnets having high magnetic field saturation and high coercive magnetic force, and the valve-port wall 4 is non-magnetic. Opposite, attracting poles of each magnetic member 7 , 8 are facing each other in the fully operational valve. However, when double-blind studies are conducted, a fully assembled “dummy” valve can be substituted with like magnetic poles facing each other, thus making a non-closing, constantly open, “placebo” unit. For testing purposes, a preferred embodiment of the moveable magnet member 8 was measured at approximately 130 milligauss(mG) at a distance of approximately 7 millimeters(mm) from the sensing coil of a DC Magnetometer. The fixed magnet member 7 had a measurement of approximately 40 mG. Both magnet members 7 , 8 were approximately 0.375 inches in diameter. For the preferred embodiment, the pressure needed to open the valve member 8 away from its seat was adjusted to be approximately 0.1 ounces per square feet(ounces/sq.ft), which correlated to approximately 15 cm height of H2O, in the catheter line.
Referring to FIGS. 2, and 5 , channel ridges 17 at the inside periphery of non-magnetic housing 3 provide fluid passage linearly between them from side-to-side of first the magnetic base member 7 and then the magnetic valve member 8 .
Referring to FIGS. 5, and 7 A, stopper shoulders 18 are provided to arrest travel of the magnetic valve member 8 at a select distance of travel away from valve-port wall 3 . 4 .
Referring to FIGS. 5, 7 A and 8 A- 8 D, the valve-port wall is provided with a valve-seat ridge 9 for reduction of valve-seat area to reduce area for accumulation of particulates in fluid passing through the system and for providing a relatively smaller surface for tightly seating into the moving valve member 8 . Moving valve member 8 can move in an interior chamber within housing section 3 in both directions as shown by arrows M 1 and M 2 . A resilient non-magnetic valve surface 9 can be provided for increased seating pressure and for selectively decreased magnetic attraction in the direction of the valve-port wall 19 . 2 . Alternative valve seat/seal configurations are illustrated in FIGS. 8B, 8 C, and 8 D. In FIG. 8C, the low-durometer, soft, resilient seal 4 . 2 can be built into the insert 4 member and its sealing ridge 19 , and a smooth surface of magnet 8 can press firmly enough to make a suitable urine flow seal. In FIGS. 8B and 8D, an FDA-approved material (eg: silicone) resilient O-ring 15 can be either bonded or inserted in the wall member of valve seat insert 4 to provide a low-pressure fluid seal against the face of the moving magnetic material 8 .
Referring to FIGS. 1 through 5, and FIGS. 7 A and 8 A- 8 D, inside corners of magnetic valve member 8 , inside corner edges of housing inlets 2 , inside corner edges of housing outlets 3 and all other corners possible can be rounded to facilitate flow through the system and to prevent accumulation of particulates in fluid passing through the system. Outside surfaces of inlet housing 2 and outside surface of outlet housing 3 also can be rounded to prevent scraping action that would tend to accumulate particles at the outside and decrease cleanliness. In addition to being rounded, the inside corners of the housing outlets can be angled from the basically symmetrical barbed inlet and outlet connectors 11 which can be selectively tapered, ribbed or otherwise designed to receive and to hold medical tubing.
Referring to FIGS. 1 through 7B, an optional soft elastic plug 12 may be inserted into a vent line 13 . 2 / 13 . 4 to serve as a safety pressure release valve (perhaps if blockage in the system caused urine pressure in the bladder to build up past some potentially hazardous number like 80-120 cm/H2O column) which would pop out to avoid renal or other physiological damage. Details are shown in FIGS. 6A and 6B. In addition, this feature could allow medicine to be injected into the urinary tract on the bladder side, if desired, to control or prevent infection. FIG. 6A has a blunt edge plug 12 . 2 , which fits within a uniform diameter vent line 13 . 2 , and an alternative version FIG. 6B has an expanded tip 13 . 4 which fits within and catches against an interior surface about narrowing vent line 13 . 4
Referring to FIG. 7B, another (threaded) hole 2 . 5 could be used to position a screw 29 /magnet 30 mechanism so as to position a third permanent magnet 30 in close proximity to the back of the “fixed” magnet member 7 , in order to alter the net magnetic field strength and thus control the valve opening pressure. The present magnet-holding insert 4 can be molded in a soft plastic material in order to make a good seal against the moving magnet face on component 8 . As shown in FIG. 7A, the South Pole of the moving magnet 8 faces the valve seat 19 at its left. This South Pole is attracted to the North Pole of the fixed magnet 7 behind the seat 19 to its left. The manual external rotational adjustment of externally adjustable screw 30 controls the magnet 30 South pole separation from the magnet 7 South pole which would allow a significant degree of valve pressure opening adjustment, or variable pressure setting, which can be desirable in certain situations. The closer magnet 30 is to magnet 7 , the less net field strength there is to attract magnet 8 . Conversely, when the screw 29 is backed off so that magnet 30 is farther apart from magnet 7 , then magnet 30 has less effect in canceling some of the strength of magnet 7 , and the opening pressure is higher. When bladder detrusor muscle atony has occurred, or when therapeutic bladder retraining is called for, lowered position of magnet 30 toward magnet 7 (screwing the magnet 30 in closer), or graduated pressure settings can provide substantial additional benefits. Currently, the opening pressure setting can be determined by the insert dimensions (assuming a consistent magnet gauss reading) and each unit can acquire a fixed pressure value during the manufacturing process. While the normal opening range is approximately 15 to approximately 30 cm/H2O, individual units can be made to operate at higher or lower pressures, within practical limits.
Head pressure to open the valve can be decreased by pressing the button inwardly and sliding the magnetic base member in the direction of the housing inlet. The valve can be totally released without any magnetic pressure to hold the valve shut when the magnetic base is slid to the extreme housing-inlet end of travel of the button stem in the stem channels. Closing pressure of the valve is increased by sliding the magnetic base member in a downstream direction toward the housing outlet.
Referring to FIGS. 2, 3 , 4 , 5 , 7 A, 7 B and 10 a siphon air vent micro-port filter 6 and cover 5 can be provided to effect a very low-pressure siphon, suction, or negative pressure from fluid passing through the housing outlets 11 . 2 and down the drain line 22 into the collection bag 27 . Typically the filter material within filter 6 , either woven or non-woven attaches by an adhesive and is packed around the housing vent hole 10 . This feature of the invention assists in holding the valve 8 open until all the fluid is emptied out of the system as well as allowing the system tubing to drain clean and dry, thus preventing moist surfaces within the system for potential bacterial growth. The vent filter 6 allows for a stream of air bubbles to enter line 22 to aid in allowing complete drainage of all fluid through line 22 , since in a gravity directed flow system an upper located vent enhances fluid flow therethrough.
Typically for construction purposes, the vent valve 10 can be positioned at the outside periphery of a valve-port wall 3 . 6 and the vent aperture 10 can be positioned in the outside periphery of an outlet housing member 3 that is created during plastic injection molding process or in the construction assembly process. The assembly can be either glued, chemically welded, ultrasonically welded, or press-fit snugly enough to remain assembled without glue.
Referring to FIG. 2, the magnetic base member 7 can be either glued or otherwise fixed in seats 4 . 6 in a position at a select distance from the valve-port wall (seat) to achieve a pre-determined pressure requirement for opening of the valve 8 in opposition to magnetic attraction of the base member 7 and the valve 8 . Alternatively, however, the magnetic base member 7 in FIG. 2 can be moved by an automatic, but very weak, drainage spring or other weakly resilient member. When pressure from the weight of fluid in the bladder 23 (shown in FIG. 10) and in the column from the bladder 23 to the bladder cycler invention 1 cause the valve 8 to open in opposition to the magnetic attraction, the spring action will cause the base member 7 to move upstream away from the moving valve member 8 and thereby decrease further the attraction between the two magnets 7 , 8 . This allows more complete emptying of the bladder contents 23 . 5 .
Although not manually-controllable, this invention provides some features of the controllable embodiment at a lower cost of construction. A springy material in this working relationship functions in the opposite direction as springs used to close valves in prior-art practices. It decreases rather than increases opening pressure of the valve when pressure in the bladder is low from being partially emptied. This configuration would require a very careful design and implementation in order to balance the static and dynamic forces precisely for operation, both in the opening pressure and to assure valve closing, sealing without leaking during urine pressure buildup to the opening threshold.
Referring to FIG. 10, this diagram traces out the cycler invention use method as the key component of a hydrodynamically-balanced cyclic urinary drainage system. The human (or animal) bladder 23 and bladder contents 23 . 5 with its two ureter inputs has its attached urethra 24 invaded by an indwelling catheter (such as a balloon-anchored Foley type) 25 . On the output end, this catheter can be connected to a clinician's (physician's) sampling port 26 , from which a urine sample can be drawn by either a conventional syringe needle or by a safety plastic canula probe.
Operation of using the cycler will now be described in reference to FIGS. 2, 3 , 4 , 5 , 7 A and 10 . Initially, the valve 8 is in a closed position to inhibit fluid flow therethrough. Arrow 14 A of FIG. 3 shows the direction of fluid flow which stops by closed seated valve 8 . A patient can use their bladder detrusor muscle 23 . 7 about the bladder 23 to cause a small amount of pressure in the catheter line 25 , 22 to cause the valve 8 in cycler 1 to pass to an open position(in the direction of arrow M 1 ) to allow fluid flow therethrough. Arrows 14 B and 14 C of FIG. 4 show fluid passing through cycler 1 . Fluid running down line 22 assists in maintaining the valve 8 in an open position by causing a hydrodynamic pulling on the valve 8 so that all fluid flow passes therethrough. The hydrodynamic pulling on the valve 8 causes by the fluid flowing through line 22 is stronger than the attractive forces between magnet valve 8 and member 7 . After all fluid passes through line 22 , no further hydrodynamic forces exist to keep the valve 8 in the open position so now valve 8 is free to move in the direction of arrow M 2 to a closed position since the attractive power of the magnets 7 and 8 causes valve 8 to move in the direction of arrow M 2 .
Unlike using actual spring biased-backed valves used in some prior art devices, the subject invention valve 8 does not function in an equivalent manner. For example, the larger the opening of the magnetic valve 8 , the less the pull(magnetic attraction with member 8 ) exists to close the valve 8 . With a spring backed valve, the greater the opening in a valve, the greater the resistance is from the compressed spring to cause a closure of the valve. For example, a patient exerting fluid pressure to open a spring biased-backed valve has greater resistance that occurs as they try to increase urination pressure. With the subject invention magnetic valve 8 , more pressure from the bladder causes less resistance against the valve 8 , and helps fluid flow therethrough.
Additionally, spring biased-backed valves have been known to cause a premature closing in a catheter line which can cause any of the medical problems referred to in the background section of the invention. The subject invention magnetic valve 8 does not prematurely close since the hydrodynamic gravity enhanced pulling of fluid downline is enough to overcome the magnetic attraction to keep the valve open. When downline fluid flow ceases, the hydrodynamic gravity enhanced pulling of fluid ceases and the magnetic attraction is enough to close off valve 8 .
The subject invention allows a person to use their bladder detrusor muscle to cause pressure selectively turn on and complete urination emptying cycle of the contents of the bladder while wearing a catheter.
The cycler 1 can be an alternative to using dangerous clamps on a catheter line, since clamps left on a catheter line for extended periods of time can be hazardous to a patient's life. The cycler 1 allows for a fluid samples to accumulate about port 26 so that an adequate sample can be retrieved when needed.
Referring to FIG. 10, the cycler invention 1 with magnetic moving valve 8 can be connected between the sampling port 26 and the specially-sized downline tubing 22 , thus forming a hydrodynamically-balanced drainage system, terminated by the collection bag 27 and its clamped-off emptying tube 28 . A preferred embodiment incorporates the connections from the catheter be made as shown, and that the downline from the outlet end of the bladder cycler valve consist of approximately 0.1875 inch inside diameter tubing, preferably of polyethylene construction. The surface tension of the watery urine fluid 23 . 5 , combined with the lumen of the catheter and the fluid pressure, fluid flow rate, viscosity, and gravitational forces have shown that these dimensions, including the length of the drainage line, can be critical parameters for proper and safe, reliable operation as a listed Class II, U.S.F.D.A.(United States Food and Drug Administration) 510(k) medical devices. As previously described, for the preferred embodiment, the pressure needed to open the valve member 8 away from its seat was adjusted to be approximately 0.1 ounces per square feet(ounces/sq.ft), which correlated to approximately 15 cm height of H2O, in the catheter line.
Referring to FIG. 11, a leg strap 20 can be provided about a human leg 20 . 5 with a swivel connection 21 that allows the bladder cycler invention 1 to be positioned when desired at a downward angle with respect to a leg 20 . 5 to which it attached. This allows a catheter or outlet drainage tubing 22 to be positioned at a slant that provides downward flow of fluid that otherwise could remain in the system between drainage cycles.
Referring to FIGS. 9A, 9 B, 9 C and 9 D, these graphs show the time relationship between pressure buildup on a test stand, such as in the configuration diagrammed in FIGS. 10-11, the valve opening pressure drop, the initiation of fluid flow, the constant flow rate until the point of emptying, the valve closing again, and the cycling period to the next pressure fill and open sequence. This period is normally approximately two to approximately four hours for the average adult, depending on amount of fluid beverages consumed, physical activity, and physiological factors such as bladder size, general health, pressure sensitivity, and the like.
In FIG. 9A, the commencement of urine flow is indicated at point 60 . The flow is quite consistent throughout the time period ending at point 61 , about 60 seconds. The flow charted from point 62 to 63 represents another bladder emptying cycle.
FIG. 9B illustrates the bladder pressure buildup cycle from 17 cm of water column pressure at point 70 to the valve opening threshold pressure of 21 cm at point 71 , dropping to zero at point 72 . At point 73 , the chart stops and a new partial cycle from point 74 at 16 cm of H2O to the opening point 75 at 22 cm of H2O.
FIGS. 9C and 9D shows charts that indicate that the flow rates and urine volumes are in the “normal” range(e.g. approximately 250 cc over 60 minutes.
Referring to FIG. 7A a manual override embodiment can allow for selectively keeping valve 8 in an open position. For example, an extra outside magnet 50 can be positioned adjacent filter 6 to have South pole S, that attracts North pole N, of moving valve 8 in an open position. The manual override of the valve can occur by selective distancing of an externally positioned magnetic 50 from the valve 8 that is attracted to it. The override gives flexibility of pressure adjustment and provides the opportunity of assuring full drainage when desired by either physician or the patient. This could manifest itself, in the event of excessive discharge of viscous matter or other mode of lumen blockage, as a welcome “safety” valve to relieve fluid pressure buildup in the line and system upstream from the cycler 1 .
While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended. | A low-pressure fluid flow control magnetic valve (cycler) device, system and method for use emptying the contents of bladder by a catheter. The device can be connected with a specified drainage tubing to function as a hydrodynamically balanced system (to empty into a typical two-liter collection bag). The cycler can be connected externally to a urinary catheter for hospital, clinical and home-care use for the emptying of the bladder of a patient through a catheter in a biologically more natural, filling and draining, cyclic manner. Fully automatic, modes of operation are provided for opening and closing this valve to empty the bladder of urine when appropriate or necessary. The modes of operation respond to normal human (or animal) body pressures, or are automatic with a manual override. This device is U.S.F.D.A. approved for human use and responds to normal human (or animal) body pressures to assist the detrusor muscle to function normally in spite of an indwelling catheter challenge. The cycler device avoids problems with bladder atone, bladder spasms, harmful struvite crystal formation, bladder retraining after surgery, and allowing urine tract washout to occur as the body's primary defense mechanism against urinary tract infections. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to Taiwan Patent Application No. 094216006 filed on Sep. 16, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a video integrated circuit and a video processing apparatus thereof; more particularly, relates to a video integrated circuit and a video processing apparatus thereof for processing and for displaying a plurality of video signals.
[0004] 2. Descriptions of the Related Art
[0005] The technology is progressing nowadays, the technology of processing image develops rapidly, and a video display apparatus is a product closely related to people's daily life. However, a conventional video display apparatus merely displaying a single image will be unable to match the need of receiving more information in a short time. For this reason, a video display apparatus offers picture-in-picture (PEP) display or picture-on-picture (POP) display is thus invented.
[0006] A conventional video display apparatus for processing a plurality of images comprises a plurality of integrated circuits. For instance, when processing a plurality of inputting digital video signals and generating a corresponding image, many kinds of integrated circuits, such as a processor, a video output/input port unit, a motion picture experts group (MPEG) codec, an integrated drive electronics (IDE) controller, etc., are required for cooperative operation. Owing to the combination of the integrated circuits, the size of the product is large, the cost is too much, and the dimensions of the product cannot reach the product requirement of light-weight, thin, short, and small in the present day. Therefore, a video integrated circuit for processing a plurality of video signals with a single integrated circuit and a video processing apparatus thereof are urgently required.
SUMMARY OF THE INVENTION
[0007] An object of this invention is to provide a video integrated circuit connected to a memory and a video display apparatus. The video integrated circuit comprises a processor, a video capture unit, a motion picture experts group (MPEG) codec, a memory control unit, and a video output unit. The video capture unit receives a plurality of digital video signals in response to a first signal from the processor and generates a processing signal. The MPEG codec receives and compresses the processing signal in response to a second signal from the processor. The memory control unit stores the processing signal in the memory in response to a third signal from the processor. The video output unit captures the processing signal from the memory via the memory control unit in response to a fourth signal from the processor and outputs the processing signal to the video display apparatus. The aforementioned first, second, third, fourth signals being accorded to the video capture unit, the MPEG codec, the memory control unit, and the video output unit are not limited to be the same signal.
[0008] The video integrated circuit may be further connected to a video graphics array (VGA) display apparatus. More significantly, the video integrated circuit may further comprise a VGA encoder for encoding the processing signal from the video output unit and for outputting the encoded processing signal to the VGA display apparatus.
[0009] The video integrated circuit may be further connected to a hardware storage device. More significantly, the video integrated circuit may further comprise an integrated drive electronics (IDE) controller for storing the processing signal in the hardware storage device in response to a fifth signal from the processor.
[0010] The video integrated circuit may be further connected to a peripheral controller interface (PCD bus. More significantly, the video integrated circuit may further comprise a PCI unit for outputting the processing signal to the PCI bus in response to a sixth signal from the processor.
[0011] The video integrated circuit may be further connected to a universal serial bus (USB) port. More significantly, the video integrated circuit may further comprise a USB unit for outputting the processing signal to the USB port in response to a seventh signal from the processor.
[0012] The video integrated circuit may be further connected to an Ethernet physical layer. More significantly, the video integrated circuit may further comprise an Ethernet medium access control layer for outputting the processing signal to the Ethernet physical layer in response to an eighth signal from the processor.
[0013] Another object of this invention is to provide a video processing apparatus connected to a memory and a video display apparatus. The video processing apparatus comprises a first video integrated circuit and a second integrated circuit. Each of the first video integrated circuit and the second integrated circuit comprises a processor, a video capture unit, a motion picture experts group (MPEG) codec, a memory control unit, a video output unit. The processor, the MPEG codec, and the memory control unit are the same as the aforementioned processor, MPEG codee, and memory control unit. The video capture unit comprises a first input node and a second input node. The video capture unit receives a plurality of digital video signals via the first input node in response to a first signal from the processor and generates a processing signal. The video output unit comprises a first output node and a second output node. The video output unit captures the processing signal from the memory via the memory control unit in response to a fourth signal from the processor and outputs the processing signal to the video display apparatus via the first output node. Wherein the second output node of the video output unit of the first integrated circuit is connected to the second input node of the video capture unit of the second integrated circuit, and the processing signal of the first video integrated circuit is transmitted to the second video integrated circuit. The signals being accorded to the aforementioned units are not limited to be the same signal as well.
[0014] The detailed technology and preferred embodiments implemented for the subject invention are described in the following paragraphs accompanying the appended drawings for people skilled in this field to well appreciate the features of the claimed invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 shows a first embodiment of a video integrated circuit in accordance with the present invention;
[0016] FIG. 2 shows a first embodiment of a video integrated circuit in accordance with the present invention; and
[0017] FIG. 3 shows an embodiment of a video processing apparatus in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] A first embodiment of the present invention is a video integrated circuit 1 for processing a plurality of digital video signals and for outputting the processed plurality of digital signals to a display, as shown in FIG. 1 .
[0019] The video integrated circuit 1 is electrically connected to a memory 101 and a video display apparatus 103 . The video integrated circuit 1 comprises a processor 105 , a video capture unit 107 , a motion picture experts group (MPEG) codec 109 , a memory control unit 111 , and a video output unit 113 . The processor 105 outputs signals via a line 161 and a bus 115 to other units of the video integrated circuit 1 . The video capture unit 107 receives a first signal 122 outputted from the processor 105 via the line 161 and the bus 115 , receives a plurality of digital video signals 102 in response to the first signal 122 , and generates a processing signal 104 . The processing signal 104 is then transmitted to the bus 115 . In this embodiment, the bus 115 is an advanced high performance bus (AHB), and the plurality of digital video signals 102 are four composite signals.
[0020] After receiving a second signal 124 outputted from the processor 105 via the line 161 and the bus 115 , the MPEG codec 109 receives and compresses the processing signal 104 in response to the second signal 124 , wherein the MPEG codec performs the compression in an MPEG-4 format. After receiving a third signal 126 outputted from the processor 105 via the line 161 and the bus 115 , the memory control unit 111 stores the processing signal 104 in the memory 101 in response to the third signal 126 . The processing signal 104 is stored in the memory 101 thereby, and the memory 101 is a synchronous dynamic random access memory (SDRAM). When the processing signal 104 is needed to be captured, the processor 105 transmits a fourth signal 128 via the line 161 and the bus 115 to the video output unit 113 . The video output unit 113 requests the memory control unit 111 to capture the processing signal 104 from the memory 101 , and outputs the processing signal 104 to the video display apparatus 103 directly or via a LCD controller (not shown) for displaying an image. The video output unit 103 may be a liquid crystal display (LCD) or a projector.
[0021] The video integrated circuit 1 further connected to a video graphics array (VGA) display apparatus 117 . The video integrated circuit 1 further comprises a VGA encoder 119 for encoding the processing signal 104 from the video output unit 113 and for outputting the encoded processing signal to the VGA display apparatus 117 . Therefore, the video integrated circuit 1 may generate a VGA signal directly to a display apparatus. In this embodiment, the VGA display apparatus 117 is a television.
[0022] The video integrated circuit 1 is further connected to a hardware storage device 121 . The video integrated circuit 1 further comprises an integrated drive electronics (IDE) controller 123 for storing the processing signal 104 generated by the video capture unit 107 in the hardware storage device 121 after receiving a fifth signal 130 from the processor 105 via the line 161 and the bus 115 . Since the hardware storage device 121 is able to store a great deal of data, the processing signal 104 would be preserved for a long time. The processing signal 140 is read from the hardware storage device 121 for displaying or for further processing when it is needed some day.
[0023] The video integrated circuit 1 is further connected to a peripheral controller interface (PCI) bus 125 . The video integrated circuit 1 further comprises a PCI unit 127 for outputting the processing signal 104 generated by the video capture unit 107 to the PCI bus 125 in response to a sixth signal 132 after receiving the sixth signal 132 from the processor 105 via the line 161 and the bus 115 . The PCI bus 125 is a standard interface for data transmission of a computer, and the processing signal 104 may be transmitted to be displayed on the computer or further processed via the PCI bus 125 .
[0024] The video integrated circuit 1 is further connected to a universal serial bus (USB) port 129 . The video integrated circuit 1 further comprises a USB unit 131 for outputting the processing signal 104 generated by the video capture unit 107 to the USB port 129 in response to a seventh signal 134 after receiving the seventh signal 134 from the processor 105 via the line 161 and the bus 115 . The USB port 129 is also an interface connected to a host, and the processing signal 104 may be transmitted to be displayed on the computer or further processed via the USB port 129 .
[0025] The video integrated circuit 1 is further connected to an Ethernet physical layer 133 . The video integrated circuit 1 further comprises an Ethernet medium access control layer 135 for outputting the processing signal 104 generated by the video capture unit 107 to the Ethernet physical layer 133 in response to an eighth signal 136 after receiving the eighth signal 136 from the processor 105 via the line 161 and the bus 115 . The processing signal 104 may be transmitted to Internet via the Ethernet physical layer 133 .
[0026] A second embodiment of the present invention is shown in FIG. 2 . A video integrated circuit 2 is also electrically connected to a memory 201 and a video display apparatus 203 . The video integrated circuit 2 also comprises a processor 205 , a video capture unit 207 , a MPEG codec 209 , a memory control unit 211 , a video output unit 213 , and a first bus 215 . The functions of the aforementioned units are the same as the functions of the corresponding units in the first embodiment, and are not depicts here.
[0027] The video integrated circuit 2 differs from the video integrated circuit 1 in further comprising a second bus 239 and a bus bridge 241 , wherein the second bus 239 is an advanced peripheral bus (APB), and the bus bridge 241 is an AHB-APB bridge for connecting the first bus 215 and the second bus 239 . The second bus 239 is further connected to an I 2 C bus 243 , an IRDA interface 245 , a storage card interface 247 , a GPIO port 249 , an audio interface 251 , a keyboard/mouse interface 253 , a UART interface 255 , and an interrupt controller 257 . The second bus 239 transmits signals to the first bus 215 via the bus bridge 241 . Therefore, any signal generated by the processor 205 , the video capture unit 207 , the MPEG codec 209 , the memory control unit 211 , or the video output unit 213 may be transmitted via the aforementioned interfaces 243 , 245 , 247 , 249 , 251 , 253 , 255 , and 257 , and a user may inputs a control signal or a datum to the video integrated circuit 2 via the aforementioned interfaces 243 , 245 , 247 , 249 , 251 , 253 , 255 , and 257 .
[0028] Both the video integrated circuit 1 and the video integrated circuit 2 receives four video signals, at least four images would be processed and displayed simultaneously thereby. The prior art requires many apparatuses for processing a plurality of video signals, and brings about a high cost and a large space necessity. The video integrated circuit of the present invention integrates the functions of many conventional integrated circuit chips on a single integrated circuit chip. The integration of the present invention decreases the area for the layout, and further saves the cost and minimizes the dimensions of the product.
[0029] The present invention further provides a video processing apparatus, and the embodiment thereof is illustrated in FIG. 3 . The video processing apparatus 3 processes and controls a plurality of digital video signals and then displays the processed and controlled plurality of digital video signals to displays, such as a LCD, a TV, a monitor, a projector, etc. The video processing apparatus 3 enables a signal display to display a plurality of images at the same time.
[0030] The video processing apparatus 3 comprises a first video integrated circuit 31 and a second video integrated circuit 33 . The units in the first video integrated circuit 31 and the second video integrated circuit 33 are identical to the video integrated circuits of the first embodiment and the second embodiment. The video capture unit 307 of the first video integrated circuit 31 and the second video integrated circuit 33 further comprises a first input node 361 and a second input node 363 . The first input node 361 is configured to receive a plurality of digital video signals 302 and to generate the aforementioned processing signal. The second input node 363 is connected to a video output unit 313 of a front end video integrated circuit. The video output unit 313 of the first video integrated circuit 31 and the second video integrated circuit 33 further comprises a first output node 365 and a second output node 367 . The first output node 365 outputs the processing signal to a video display apparatus 303 , and the second output node 367 is connected to the second input node 363 of the video capture unit 307 of a back end video integrated circuit. In this embodiment, the second output node 367 of the video output unit 313 of the first video integrated circuit 31 is connected to the second input node 363 of the video capture unit 307 of the second video integrated circuit 33 , and the processing signal of the first video integrated circuit 31 would be inputted into the second video integrated circuit 33 .
[0031] If both the video integrated circuit 1 and the video integrated circuit 2 can process four video signals, then the first output node 365 and the second output node 367 of the video output unit 313 of the second video integrated circuit 33 can output eight images respectively, wherein four images of the eight images are generated from the digital video signal 302 of the first input node 361 of the video capture unit 307 of the first video integrated circuit 33 , and the other four images are generated from the digital video signal 304 of the first input node 361 of the video capture unit 307 of the first video integrated circuit 33 . The second video integrated circuit 33 enables the eight images to be displayed simultaneously on the video display apparatus 303 via the first output node 365 .
[0032] Though the embodiment is illustrated with the video processing apparatus comprising two video integrated circuits, people skilled in this field may proceed with a variety of modifications having the video processing apparatus with more than two video integrated circuits. The video processing apparatus comprising four video integrated circuits, for example, may display sixteen images at the same time.
[0033] The above disclosure is related to the detailed technical contents and inventive features of the subject invention. People skilled in this field may proceed with a variety of modifications and replacements based on the disclosures and suggestions of the invention as described without departing from the characteristics thereof. Nevertheless, although such modifications and replacements are not fully disclosed in the above descriptions, they have substantially been covered in the following claims as appended. | A video integrated circuit and a video processing apparatus thereof, connected to a memory and a video display apparatus, for processing and displaying a plurality of video signals are provided. The video integrated circuit and the video processing apparatus comprise a processor, a video capture unit, a motion picture experts group decoder, a memory control unit, and a video output unit. The video integrated circuit and the video processing apparatus generate a plurality of images corresponding to the plurality of video signals after processing. The video integrated circuit and the video processing apparatus displaying the plurality of images in one single chip decrease the cost and the size of products. | 7 |
[0001] This application claims priority from United States Provisional Application No. 60/328,421 filed Oct. 12, 2002.
FIELD OF THE INVENTION
[0002] The present invention relates to a flow regulator for regulating the flow rate through a flexible tube and more specifically to a mechanism that laterally pinches a flexible tube for a fine adjustment of the flow.
BACKGROUND OF THE INVENTION
[0003] Modern medical treatments often involve the use of intravenous fluids. The fluids may contain a wide variety of agents that affect the patient. The flow rate of medical fluid provided to the patient is critical in order to ensure that the patient is properly treated. Thus, it is important to provide a simple mechanism for adjusting the flow of a liquid in a tube. In U.S. Pat. No. 4,515,588, filed 16 May 1983, Amendolia suggests inserting an adjustable valve in the fluid path to control the flow rate. This prior art works with flexible plastic tubing. The tube is cut and an adjustable valve is inserted. The valve permits fine flow adjustment. Clearly, when such a valve is used, it is necessary to ensure that the sterilized plastic hose remains free of germs. Thus, a sterilized knife is used to cut the tubing. Clearly, the knife must be used immediately if it is to remain sterile. Although the tasks of cutting the tubing and inserting the flow regulator are relatively simple they take time and in a hospital environment, time is very costly.
[0004] Alternatively, in U.S. Pat. No. 3,215,394, filed 23 Apr. 1962, Sherman describes a simple method of controlling the flow of liquid in a flexible plastic tube by deforming the tube. The Sherman prior art relies on a cam that receives an external rotational input in order to interfere with the geometry of flexible tubing that the liquid flows through. This prior art does not require that the flexible plastic tubing be cut in order to control the flow of liquid therein. Unfortunately, the degree of control over the flow rate is poor. The device is simple however the variety of parts needed to build it and the assembly of those parts leads to a device that is fairly costly.
[0005] In U.S. Pat. No. 4,786,028, filed 24 Feb. 1987, Hammond describes a fluid flow adjustment mechanism much like the mechanism of the Sherman prior art. Hammond however inserts a block between the cam and the flexible tubing. This reduces the likelihood of wear on the tubing substantially, however the device does not provide the precise flow desired and demanded in a wide variety of medicinal applications.
[0006] This device is improved upon by D'Alessio et al. in U.S. Pat. No. 5,259,587 in which a fluid control mechanism is provided using a cylinder as a cam that pushes a surface of a second cylinder against a flexible tube. In this case, the deformation of the tube is controlled using a wheel with a ratchet mechanism. The ratchet prevents the cam from rotating out of position once it has been set. Although this mechanism offers a somewhat improved flow control mechanism over the related prior art, it also introduces additional components. Clearly, the components used will require some assembly and that cost will be apparent in the cost of the device.
[0007] Thus, a variety of prior art devices exist featuring a ram that moves perpendicular to a tube to deform the tube in order to adjust a flow of fluid within the tube. These devices are generally designed to work with special flexible tubing. The flexibility of flexible tubing is described by a durometer rating. A typical durometer rating of flexible tubing used in fluid flow adjustment devices for dental applications is 60 to 80 on a Shore A scale. This type of tubing is quite flexible and therefore relatively easy to deform. Harder tubing having Shore A durometer ratings of 85 and 90 are also quite common; however, these stiffer types of tubing are less well suited to use with this type of prior art device as they require substantially more effort to produce the desired deformation.
[0008] An alternative design causes three points bending in a flexible tube in order to control a flow of fluid therein. Thus, the flexible tubing is held by two supports and ram engages the tubing between the supports. The degree of engagement of the ram affects the fluid flow within the tube. Unfortunately, this method does not provide precise flow control.
[0009] Ideally, these devices would provide a more linear relationship between the position of an input control and the flow mechanism. For example, when the input is half way between the fully open position and the fully closed position ideally the flow provided would be half the flow associated with the fully open position. Thus, the position of the input would be directly proportional to the flow of liquid that the mechanism provides.
[0010] Ideally, a flow regulator should provide a consistent and directly proportional relationship between the displacement of an input and the flow rate. However, a consistent flow rate is not obtained with many of the prior art flow rate regulators because the pressure exerted on the wall of a flexible tubing is perpendicular to the fluid flow, which modifies the shape of the internal surface of the tubing without substantially modifying the flow of the fluid. A deformation from, for example, a circular shape to a somewhat elliptical shape does not change the flow substantially, even though a certain displacement is imposed on the wall of the flexible tubing to achieve such a deformation.
[0011] Clearly, it would be beneficial to provide a fluid flow adjustment device that provides highly precise flow control by deforming a flexible tube. Additionally, it would be beneficial if the device is simple and easily produced using very inexpensive components.
OBJECT OF THE INVENTION
[0012] It is an object of this invention to provide a fine adjustment system for regulating a fluid flow passing through flexible tubing which does not require cutting the tubing.
[0013] It is an object of this invention to provide a fine flow pinch adjust system that permits an approximately consistent fine control of a flow rate.
SUMMARY OF THE INVENTION
[0014] The invention describes a fine flow pinch adjust mechanism comprising:
[0015] a channel for supporting a flexible tube bent by a fixed substantial angle at a first location; and,
[0016] an opening for receiving a corresponding member and extending toward the first location, the opening for supporting controlled motion of the member in a direction toward and away from the first location.
[0017] Additionally, the invention teaches a fluid flow adjustment mechanism for controlling a fluid flow rate in a length of flexible tubing, comprising:
[0018] a housing having a surface for engaging the length of flexible tubing, the engagement of the surface with the length of flexible tubing supporting a substantial first bending deformation of the flexible tubing in a first portion of the length of flexible tubing, said first bending deformation occurring without preventing a flow of fluid within the flexible tubing; and,
[0019] a ram mechanically engaged with said housing, the ram for selectably engaging the first portion to compress the first portion against the housing thereby causing a second deformation of the first portion in dependence upon the position of the ram.
[0020] In another embodiment of the invention there is provided a fine flow pinch adjust comprising:
[0021] a casing having:
[0022] a second opening;
[0023] a first threaded cylindrical opening opposite the second opening, the first and second openings in fluid communication with each other; and,
[0024] a third opening in fluid communication with the first and second openings; and,
[0025] a screw having a threading for engaging with a threading of the first threaded cylindrical opening and for moving in and out of the first threaded cylindrical opening in response to a rotation of the screw relatively to the first threaded cylindrical opening,
[0026] wherein in use a flexible tube is positioned between the second and third openings in other than a straight path, the flexible tubing being engageable by the screw.
[0027] The invention also describes a fine flow pinch adjust mechanism for controlling a flow in a length of flexible tubing comprising:
[0028] means for supporting and bending a portion of the length of flexible tubing; and,
[0029] means for selectably deforming the portion to control a rate of fluid flow therein absent substantially affecting the bending of the portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Exemplary embodiments of the invention will now be described in conjunction with the following drawings, in which:
[0031] [0031]FIG. 1 is a section view of a prior art flow regulator that deforms a length of flexible tubing to affect the flow of liquid therein;
[0032] [0032]FIG. 1 a is section view of an undeformed tube;
[0033] [0033]FIG. 1 b is a section view of tube after a substantial deformation from an undeformed state;
[0034] [0034]FIG. 1 c is a section view of a tube sufficiently deformed to affect a flow of fluid therein;
[0035] [0035]FIG. 1 d is a section view of the tube shown in FIG. 1 c after a further substantial deformation;
[0036] [0036]FIG. 2 is an isometric view of a prior art fluid flow adjustment device with a threaded ram mounted perpendicularly to a flexible tube;
[0037] [0037]FIG. 3 is a schematic diagram of a fluid flow adjustment mechanism according to an embodiment of the present invention;
[0038] [0038]FIG. 4 is a representative section view of a fluid flow adjustment mechanism according to an embodiment of the present invention featuring a flexible tube and a threaded ram;
[0039] [0039]FIG. 4 a is a cross section view of a length of flexible tubing absent deformation;
[0040] [0040]FIG. 4 b is a cross section view of a length of flexible tubing that is deformed as a result of contact with a curved flange;
[0041] [0041]FIG. 5 is a representative section view of a fluid flow adjustment mechanism according to a preferred embodiment of the present invention in which a length of flexible tubing is being deformed thereby restricting a flow of liquid;
[0042] [0042]FIG. 5 a is a section of tubing deformed by a mechanism consistent with the preferred embodiment of the invention;
[0043] [0043]FIG. 6 is a hidden line view of an embodiment of the invention;
[0044] [0044]FIG. 7 is a isometric view of an embodiment of the invention with a removable section for quick installation; and,
[0045] [0045]FIG. 8 is an isometric view of a panel supporting a plurality of fluid flow adjustment mechanisms according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0046] Referring to FIG. 1, a section view of a fluid flow control mechanism according to the prior art of Sherman as disclosed in U.S. Pat. No. 3,215,394 is shown. This prior art device controls the flow of liquid in a tube 11 by compressing the tube 11 between a cam 12 and a housing 13 . Referring to FIG. 1 a, a cross section view of a tube 11 is shown. The tube 11 has a circular outside diameter with a circular bore 15 concentric with the outside diameter. The section view shown in FIG. 1 a is consistent with a flexible tube used in the mechanism described in FIG. 1 with the section view in which the cam 12 does not cause deformation of the tubing 11 . As the cam 12 is displaced into the tube 11 by a small amount it deforms the tube 11 slightly. Referring to FIG. 1 b, the flexible tube is shown having been slightly deformed with respect to the section view of FIG. 1 a. Although the bore of the tube is now somewhat deformed, the cross sectional area of the bore has not changed significantly. Consequently, the flow rate within the tube 11 is not changed significantly, either.
[0047] Referring to FIG. 1 c, a cross section view of the tube shown in FIG. 1 proximate the cam 12 is shown. The cam 12 has been brought down and the tube 1 I has been deformed, thereby affecting the flow rate within the tube 11 . As the cam 12 is brought down a same small amount, as described with reference to the paragraph associated with FIG. 1 a, the bore of the tube is narrowed significantly. Referring to FIG. 1 d, the cross section view of the tube shown in FIG. 1 c is shown after a small displacement of the cam 12 . It is apparent that the cross sectional area of the bore has been reduced significantly as a result of the small displacement of the cam. A person of skill in the art will realize that such a displacement would likely have a substantial effect on the flow rate within the bore of the tube. Clearly, unless the fluid flow control mechanism is intended as a valve with an open state and a closed state, a more consistent and even response between a change in position of the member used to deform the tube and flow rate within the tube is desirable.
[0048] An alternative to the prior art of Sherman is shown in FIG. 2. It incorporates a simpler mechanism in which a screw 21 is used to deform the flexible tubing 22 instead of a cam. Although the screw 21 provides finer adjustment than the device incorporating a cam, this device also has similar sensitivity problems as discussed with respect to the prior art of Sherman. Additionally, it is not uncommon that when a hand operated screw mechanism is used to deform the flexible tubing and the flow is stopped, a considerable torque is necessary in order to move the screw 21 backward to permit a fluid flow. This problem is generally known as stiction. Once the stiction torque has been overcome the screw is very easy to rotate. Unfortunately, when this mechanism is used with small diameter tubing typical of medical applications it is not uncommon that the working range of the screw 21 is about one quarter turn. Consequently, when a health care professional chooses to permit a minimal fluid flow from such a device that has been set to prevent fluid flow it is not uncommon that the initial fluid flow is excessive until the device is properly adjusted. Typically, these devices use a UNC#10-32 screw because they are very robust, commercially available and inexpensive. This type of screw has a thread pitch of 32 threads per inch. While it is certainly possible to create screws having finer threads allowing a greater working range of the mechanism the finer threads are not commonly available and substantially more difficult to produce, particularly in molded plastics thus leading to higher manufacturing costs.
[0049] Referring to FIG. 3, a schematic diagram of a fluid flow adjustment mechanism according to a first embodiment of the invention is shown. The mechanism includes a housing 30 with a threaded hole 31 . The housing 30 also has a surface with a corner feature 36 for supporting flexible tubing. The surface of the corner feature 36 is shaped to cause a substantial bend in a length of flexible tubing supported therein proximate the first opening 31 .
[0050] Referring now to FIG. 4, a side view of the fluid flow adjustment mechanism of FIG. 3 is shown with a length of flexible tubing 40 supported by the surface of the corner feature 36 and a screw 44 engaged into the threaded hole 31 . The flexible tubing 40 is shown with a first section line 41 and a second section line 42 . Section line 42 is present in a region where the flexible tubing is supported by the corner feature 36 while section line 41 corresponds to a region of the flexible tubing in which the cross section of the tube is not substantially deformed.
[0051] Referring to FIG. 4 a, a cross section view of a length of flexible tubing 40 corresponding to section line 41 of FIG. 4. In such a region, the external diameter of the tubing 40 is circular. In this case, the tubing has a substantially equal wall thickness and as a result, the interior diameter of the tubing is also circular. Referring now to FIG. 4 b, a section view corresponding to section line 42 of FIG. 4 is shown. The surface 37 of the corner feature substantially deforms the flexible tubing 40 . The resulting cross section of the flexible tubing provides a bore having bulges 45 at either side. Clearly, in this configuration, most of the fluid flow will occur proximate the bulges 45 , with less fluid flow proximate the middle of the tubing.
[0052] Referring now to FIG. 5, the fluid flow adjustment mechanism of FIG. 4 is shown with the tapered end of a screw 44 in contact with the flexible tubing 40 . When the screw 44 further compresses and deforms the flexible tubing 40 , the cross sectional area of the interior of the tubing 40 is reduced. Referring to FIG. 5 a, the reduction of the interior cross section area of the tubing 40 is approximately proportional to the travel of the screw 44 . When the screw 44 is properly engaged with the flexible tubing 40 , the flow of liquid within the flexible tubing 40 is affected in an approximately linear relationship with the position of the screw 44 . The angle of the taper on the tapered end of the screw 44 affects the distance that the screw 44 travels to go from a first state of not contacting the flexible tube 40 to another state of substantially preventing flow within the flexible tube 40 . As a result, when the taper is properly chosen, a relatively coarse rotation of the bolt results in a relatively fine adjustment of the flow within the flexible tubing despite the use of standard threads on the bolt, such as UNC#10-32. Further, since the screw 44 is not being pushed directly into the tube 40 this design reduces the likelihood of the screw 44 sticking to the tube 40 . In the unlikely event that the screw 44 does stick to the tubing 40 a twist of the screw 44 with sufficient torque will likely still cause a larger than necessary twisting of the screw 44 . Fortunately, the taper of the screw 44 is easily chosen to permit a substantial rotation of the screw in to position permitting a negligible flow from a fully closed position. Therefore, even with some small rotation associated with overcoming stiction a large fluid flow need not be produced.
[0053] It will be apparent to one of skill in the art of mechanical design that the embodiment of the invention shown in FIG. 5 is very easily produced. Additionally, since the assembly of the device comprises positioning a tube in a housing, inserting a screw into the housing and rotating the screw, it is apparent that the device is optionally provided as a set of discrete components that are easily assembled immediately before use. A wide variety of materials are suitable for the housing. The housing is easily produced by molding or casting, both of these techniques are well known in the art for producing robust components that are very cost effective in large volumes. Clearly, the production of the device according to the invention is in no way limited to these techniques as the device is easily produced, for example, by machining rod material or other standard size stock. Additionally, the screw is easily produced using known techniques. Thus, the fluid flow regulator according to the embodiment of FIG. 5 is exceptionally cost effective while providing a quality of fluid flow rate control that is more than adequate for many applications.
[0054] A wide variety of variations to this basic design are possible. As shown in FIG. 6, a second embodiment of a flow regulator according to the invention is shown. This embodiment features a threaded outside portion 69 that assists mounting of the flow regulator in a panel. In this embodiment, a corner feature 62 is provided in a housing 61 . In this case, the corner feature is formed by the intersection of a first circular bore 65 and a second circular bore 66 . A tapered bolt 64 is engaged with a threaded portion of the second bore 66 . A length of tubing 60 is provided in the continuous channel as shown and secured therein. The tapered bolt 64 provides pressure on the tubing 60 in dependence upon the position of the tapered bolt 64 relative to the tubing 60 . In this embodiment, an end of the tubing 60 is provided to the first bore 65 and pushed through the second bore 66 . In this embodiment of the invention, the molded plastic housing 61 has a substantial amount of material in the region between the threaded section of the housing 61 and the corner feature. The presence of this material results in the housing being very strong. Thus, this configuration permits the use of relatively weak materials for the housing 61 , without compromising the structural integrity of the finished device. In this embodiment of the invention, the tapered bolt 64 has been chosen such that the outside diameter of the tapered bolt 64 is marginally smaller than the inside diameter of the second bore 66 proximate the intersection of the first bore 65 and the second bore 66 . This geometry helps to support the tapered bolt 64 . Thus, the axis of rotation of the tapered bolt 64 is positioned at the centerline of the second bore, even if the threaded engagement between the tapered bolt 64 and the housing 61 is sufficiently loose to permit some slop. Therefore, when the tapered bolt 64 deforms the flexible tubing 60 , the flexible tubing will not bend the tapered bolt 64 . This also permits the use of stiffer flexible tubing than would ordinarily be associated with a simple fluid flow adjustment device. Devices built according to this embodiment of the invention have been successfully used with flexible tubing having a Shore A durometer rating of 85 to 90. In the embodiment according to FIG. 6 the first bore 65 and the second bore 66 are shown having a same diameter although alternative embodiments may feature different diameters for the different bores. Clearly, a wide variety of materials are suitable for the different components of the device.
[0055] Referring to FIG. 7, an embodiment of the invention is shown having a panel to permit easy access to the channel used for supporting the flexible tubing. The device according to this embodiment comprises: a threaded member 74 , a main housing 71 , a panel 79 and a length of flexible tubing 70 . The main housing 71 has a first channel 75 a formed therein and a second channel 76 a formed therein. Concentric to the second channel 76 a is a threaded hole for supporting the threaded member 74 . In use, a length of flexible tubing 70 is provided to the main housing 71 . The flexible tubing 71 is deformed so that it is supported by both the first channel 75 a and the second channel 76 a, with the flexible tubing 70 properly positioned and the panel 79 positioned and engaged with the main housing 71 . The threaded member 74 is then engaged with the threaded hole of the main housing 71 . This embodiment of the invention permits the use of the invention with a length of tubing absent the need to feed the tubing through the device. This is beneficial for example in an industrial environment in which a variable flow rate mechanism has failed such that it no longer serves to restrict the flow of a fluid. The failed mechanism is critical to the operation of a production and thus, the production line is unable to function properly. The device according to this embodiment of the invention is easily coupled to a length of flexible tubing to establish control of the flow rate within the tubing. This embodiment is easily attached to the flexible tubing without the need to empty the tubing or disconnect the tubing. This embodiment features a fluid flow rate adjustment mechanism consistent with the previous flow rate mechanism of the previous embodiment. Optionally, the panel 79 includes a third channel feature and a fourth channel feature that work in co-operation with the first channel feature 75 a and the second channel feature 76 a of the main housing 71 . The panel 79 shown in FIG. 7 is shown secured to the main housing 71 with a screw but this need not be the case. In an alternative embodiment panel 79 has a spring-loaded members that snap into corresponding features of the main housing 71 . Optionally, the attachment of the panel is permanent. Clearly, a person of skill in the art of mechanical design will be aware of a wide variety of techniques available for attaching two parts together for either permanent or temporary engagement.
[0056] Referring to FIG. 8, a panel of fluid flow adjustment mechanisms according to the invention is shown. The panel 80 has a first surface 81 for supporting a plurality of flow regulators 82 . Each of the flow regulators 82 has an input flexible tube 83 and an output flexible tube 84 . The panel 80 is shown supporting only eight flow regulators 82 for illustrative purposes. Clearly, the panel is easily modified to support different numbers of flow regulators. One primary concern when producing a panel 80 of this type is the routing of the tubing. Clearly, routing sixteen lengths of flexible tubing as shown in FIG. 8 is not a significant problem however when hundreds of lengths of flexible tubing are used this often presents a problem. In this application, the tubing is bent approximately 90 degrees when it is installed in the housing of the flow regulator 82 . Thus, a very quick inspection of the panel will verify which output flexible tube 84 is associated with which flow regulator 82 . As previously described with reference to FIG. 6, embodiments of the invention are particularly well suited for use with flexible tubing which is stiffer than the flexible tubing normally associated with flow regulators that rely on deforming a length of flexible tubing. Thus, the likelihood of an individual length of tubing being inadvertently deformed is reduced.
[0057] Although the invention is well suited to controlling the flow of a medicinal fluid to a patient, a wide variety of other applications exist. A fluid flow adjustment mechanism according to the invention is equally well suited for use in a laboratory or industrial environment. Since the liquid whose flow is being controlled is not in contact with the fluid flow adjustment mechanism the mechanism need not be sterilized to ensure that it does not contaminate the liquid flow. Additionally, the design of the device permits scaling the embodiments of the invention to work with significantly larger flexible tubing.
[0058] The embodiments of the invention provide a very simple device for regulating a flow of liquid within a length of flexible tubing. The flow regulation is achieved with a highly controllable response to adjustments of an external input due to a substantial reduction in stiction. The fluid flow adjustment mechanism is easily and cost effectively produced from a wide variety of materials. Although embodiments of the invention feature tapered bolts that are rotated by a user to deform the flexible tubing, a wide variety of different options are available for deforming the flexible tubing. For example, a variable position solenoid is optionally incorporated to deform the plastic tubing in response to an electrical signal. Alternatively, a conventional bolt or a bolt with a ball nose is used in place of a tapered bolt.
[0059] A person of skill in the art of mechanical design will be aware of a variety of alternative embodiment of the invention. For example, the embodiments presented herein use a threaded member, such as a bolt with a smooth tip, to engage and deform the tube. This need not be the case. For example the invention will work with a variety of different elements to deform the flexible tubing, such as an appropriately shaped cam and tapered cylinder. Numerous other embodiments may be envisaged without departing from the spirit and scope of the invention. | A fine flow pinch adjust has a T shaped fluid communication path. A flexible tube is inserted within the fluid communication path in other than a straight path. A screw is inserted in one branch of the T unoccupied by the flexible tubing such that the screw cooperatively engages threads on the opening wall and such that the screw can engage the tubing when turned sufficiently in a known direction. | 5 |
TECHNICAL FIELD
The disclosure relates to the field of communications, particularly to a method and system for quickly updating ranging results of Optical Network Units (ONUs) by an Optical Line Terminal (OLT) in a Passive Optical Network (PON) system under a protection state.
BACKGROUND
With the development of wideband access technologies, operators gradually accept and deploy an Optical Access Network (OAN) to provide service of faster rate and higher quality for users. A PON is a point-to-multipoint optical access technology. As shown in FIG. 1 , the PON is composed of an OLT, ONUs and an Optical Distribution Network (ODN) where an optical splitter is located, and one OLT is connected with a plurality of ONUs through the ODN at the same time. Wherein the ONU can be terminals of various forms, including an Optical Network Terminal (ONT) used for family users, a Multi-Dwelling Unit (MDU) used for multi-dwelling users, and a business user type ONU used for various commercial occasions and residential users.
As shown in FIG. 1 , in practical deployment, the distances between the ONUs and the OLT will change along with the actual physical placement locations of the ONUs, some are near and some are far. Considering such circumstances, in the PON system based on a Time-Division Multiple Address (TDMA) technology, the ONUs with different physical distances to the OLT are required to be regulated to be equidistant to the OLT in logical sequence, therefore, conflict is avoided when the OLT distributes an uplink time slot to each ONU, and all the ONUs can send data on the uplink according to the time slot arrangement of the OLT. The means of regulating the ONUs to be equidistant to the OLT is to calculate an equalization delay signal corresponding to each ONU based on different distances between all the ONUs to the OLT, and then each ONU, when transmitting data on the uplink, can adds the corresponding delay based on the equalization delay signal corresponding to the ONU itself, so that it can be ensured that the conflict resulting from transmitting data by the ONUs on the uplink is avoided.
At present, in the existing standard of G bit Passive Optical Network (GPON), the equalization delay signal is transmitted by the OLT through a Ranging_time message when the ONUs are in an O4 state, namely in a ranging state, Here, the Ranging_time message belongs to a Physical Layer Operation Administration and Maintenance (PLOAM) message. The OLT may transmit a Ranging_time message to each ONU for three times after measuring the distance of the ONU, wherein an equalization delay signal corresponding to the ONU is included in the Ranging_time message; and the ONU performs follow-up corresponding processing after receiving the Ranging_time message. With the method, operations can be performed well under normal conditions, but a problem occurs in a trunk optical fiber protection mode.
In the application of PON deployment, some types of users require higher security and hope that operators can provide a security mechanism to ensure that the service channels are not interrupted, or require secondarily that, the service channels can restore quickly as soon as the service channels are interrupted. Therefore, protection and quick switching are required on the PON which bears the operation of user service, and PON protection mode needs to be adopted. In the PON protection mode, the OLT is connected with multiple ONUs through one or more optical splitters; there can be at least one optical interface on the OLT; a channel that each optical interface is connected with each ONU through the optical splitter is called as a protection channel, namely, there are at least one protection channel on the OLT; and the protection channels are divided into a primary channel and a standby channel in general. FIG. 2 is a diagram illustrating the architecture of an existing typical protection network adopting a PON protection mode in a trunk optical fiber protection mode; As shown in FIG. 2 , the channel corresponding to optical interface PON LT ( 0 ) is a primary channel, and the channel corresponding to optical interface PON LT ( 1 ) is a standby channel.
In the trunk optical fiber protection mode, if the protection mode is triggered, all the ONUs are required to be switched to the channel corresponding to the standby OLT. On the basis of the difference of physical positions of the primary OLT and the standby OLT, each ONU is required to update the equalization delay signal, and the updated equalization delay signal should correspond to the physical distance between the ONU and the standby OLT, that is to say, each ONU can continue working normally only after being regulated to be logically equidistant to the standby OLT, so that conflict on the uplink can be avoided.
Following the mode defined in the existing GPON standard, the equalization delay signal corresponding to each ONU connected with the OLT is calculated at the OLT side, and then the OLT notifies all the ONUs connected with the OLT of the equalization delay signal corresponding to each ONU through the Ranging_time messages; and in order to ensure the transmission reliability of the equalization delay signal, the Ranging_time messages need to be transmitted for three times. Since it takes 125 us to transmit the message each time, when the number of the ONUs supported by the OLT reaches 128, it takes 125×3×128 us=48 ms to notify ONUs of the corresponding equalization delay signal just through transmitting the Ranging_time messages, furthermore, before the Ranging_time messages are transmitted under an O4 state, time is spent by the OLT for the ranging of the standby OLT and the ONU, so that the requirement of performing service switching within 50 ms cannot be satisfied basically. Therefore, for the service terminal, the protection effect of protection switching of the practical primary/standby OLT cannot be embodied. In sum, in the trunk optical fiber protection mode, if the existing method above is adopted, the OLT needs to transmit an equalization delay signal corresponding to each ONU to the ONU only through a one-to-one communication mode, so that the quantity of message is too large, and requirement of performing service switching within 50 ms cannot be satisfied basically; therefore, protection switching cannot be implemented effectively in effect.
SUMMARY
In view of this, the disclosure aims to provide a method and system for quickly updating ranging results of ONUs by an OLT, which saves information, and can realize quick switching in a protection mode, so that protection switching is realized effectively.
In order to achieve the above-mentioned purposes, the technical solution of the disclosure is implemented as follows.
A method for quickly updating ranging results of Optical Network Units (ONUs) by an Optical Line Terminal (OLT), comprises:
distributing an acquired ranging difference to all the ONUs by the OLT; and
implementing quick updating of ranging result of a current ONU itself by the current ONU according to the acquired ranging difference.
Wherein the ranging difference may comprise a round trip delay ranging difference RTD Δ between a primary channel and a standby channel.
Wherein under the condition that the ONU is in a ranging state after protection switching is triggered, the method may further comprise: distributing the RTD Δ to all the ONUs by the OLT in the form of a broadcast message.
Wherein when the primary channel is switched to the standby channel, the process of implementing quick updating of the ranging result of the current ONU itself according to the RTD Δ may comprise: obtaining a current equalization delay signal corresponding to the standby channel according to the RTD Δ and an equalization delay signal corresponding to the primary channel before, and updating the equalization delay signal; and
when the standby channel is switched to the primary channel, the process of implementing quick updating of the ranging result of the current ONU itself according to the RTD Δ may comprise: obtaining a current equalization delay signal corresponding to the primary channel according to the RTD Δ and an equalization delay signal corresponding to the standby channel before, and updating the equalization delay signal.
Wherein under the condition that the ONU is in a normal working state, the method may further comprise: distributing the RTD Δ to all the ONUs by the OLT in the form of a broadcast message.
Wherein the process of implementing quick updating of the ranging result of the current ONU itself according to the RTD Δ may comprise: obtaining a current equalization delay signal corresponding to the standby channel in advance according to the RTD Δ and an equalization delay signal corresponding to the primary channel before, and updating a management information base; and enabling the updated equalization delay signal after the protection switching from the primary channel to the standby channel is triggered; or
the process of implementing quick updating of the ranging result of the current ONU itself according to the RTD Δ may comprise: obtaining a current equalization delay signal corresponding to the primary channel in advance according to the RTD Δ and an equalization delay signal corresponding to the standby channel before, and updating a management information base; and enabling the updated equalization delay signal after the protection switching from the standby channel to the primary channel is triggered.
Wherein the broadcast message may comprise a modified Ranging_time message or a custom dedicated message.
A system for quickly updating ranging results of Optical Network Units (ONUs) by an Optical Line Terminal (OLT), comprises a distributing unit and an updating unit, wherein
the distributing unit is configured to distribute an acquired ranging difference to all the ONUs by an OLT; and
the updating unit is configured to implement quick updating of ranging result of a current ONU itself by the current ONU according to the acquired ranging difference.
Wherein the distributing unit may be further configured to distribute an acquired RTD Δ to all the ONUs by the OLT; wherein the RTD Δ may comprise a round trip delay ranging difference between a primary channel and a standby channel.
Wherein the distributing unit may be further configured to distribute the RTD Δ to all the ONUs in the form of a broadcast message by the OLT under the condition that the ONU is in a ranging state after protection switching is triggered.
Wherein the updating unit may be further configured to obtain a current equalization delay signal corresponding to the standby channel according to the RTD Δ and an equalization delay signal corresponding to the primary channel before under the state of switching from the primary channel to the standby channel, and update the equalization delay signal; or
the updating unit may be further configured to obtain a current equalization delay signal corresponding to the primary channel according to the RTD Δ and an equalization delay signal corresponding to the standby channel before under the state of switching from the standby channel to the primary channel, and update the equalization delay signal.
Wherein the distributing unit may be further configured to distribute the RTD Δ to all the ONUs in the form of a broadcast message by the OLT under the condition that the ONU is in a normal working state.
Wherein the updating unit may be further configured to obtain a current equalization delay signal corresponding to the standby channel in advance according to the RTD Δ and an equalization delay signal corresponding to the primary channel before, and update a management information base; and enable the updated equalization delay signal after the protection switching from the primary channel to the standby channel is triggered; or
the updating unit may be further configured to obtain a current equalization delay signal corresponding to the primary channel in advance according to the RTD Δ and an equalization delay signal corresponding to the standby channel before, and update a management information base; and enable the updated equalization delay signal after the protection switching from the standby channel to the primary channel is triggered.
In the disclosure the OLT distributes the acquired ranging difference to all the ONUs; and the current ONU implements quick updating of the ranging result of the current ONU itself according to the acquired ranging difference.
With the disclosure, the distributed ranging difference is the same to all the ONUs, so that the one-to-all communication mode can be adopted for sending messages; therefore, the quantity of messages is saved, the message sending process is simplified, a period of time during which all the ONUs restore to a normal working state is shortened and measured in the order of the millisecond, quick switching can be realized under the protection mode, and protection switching can be realized effectively.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating the architecture of an existing PON;
FIG. 2 is a diagram illustrating the architecture of a protection network in a trunk optical fiber protection mode; and
FIG. 3 is a diagram illustrating the implementation process of a method according to the disclosure.
DETAILED DESCRIPTION
The basic thought of the disclosure is that: an OLT distributes the acquired RTD Δ to all the ONUs, and ranging results of the ONUs are updated quickly by the ONUs according to the RTD Δ .
Below the implementation of the technical solution is further illustrated in detail in combination with the drawings.
As shown in FIG. 3 , a method for quickly updating ranging results of ONUs by an OLT comprises the steps as follows.
Step 101 : an OLT distributes the acquired ranging difference to all the ONUs.
Wherein the ranging difference can be RTD Δ which is a round trip delay ranging difference between a primary channel and a standby channel. RTD Δ =RTD primary −RTD standby , where RTD primary is the value of a round trip delay of the primary channel, and RTD standby is the value of a round trip delay of the standby channel.
Step 102 : a current ONU implements quick updating of the ranging result of the current ONU itself according to the acquired ranging difference.
Here, the current ONU refers to the ONU acquiring the ranging difference. It must be pointed out that not all the ONUs implements quick updating immediately at the same time, but the current ONU which has acquired the ranging difference implements quick updating of the ranging result of the current ONU itself according to the ranging difference, and other ONUs can implements quick updating of the ranging results according to the ranging difference only after the ONUs acquire the ranging difference.
For the technical solution consisting of step 101 and step 102 , after step 102 is executed, on the basis of quick updating of ranging results, the time requirement of service switching can be satisfied, so that protection switching can be accomplished quickly.
Since the ONUs acquire RTD Δ at different times, the quick updating of ranging results of the ONUs is implemented differently, which is elaborated in two situations below.
One situation is that the ONUs are in a ranging state after protection switching is triggered.
Step 101 specifically comprises: under the condition that the ONUs are in a ranging state after protection switching is triggered, the OLT distributes the RTD Δ to all the ONUs in the form of a broadcast message.
When protection switching is switched from the primary channel to the standby channel, step 102 specifically comprises: a current equalization delay signal corresponding to the standby channel is obtained according to the RTD Δ and an equalization delay signal corresponding to the primary channel before, and the equalization delay signal is updated. At this moment, the formula of Eqd standby =Eqd primary +RTD Δ can be adopted, where Eqd standby is an equalization delay signal corresponding to the standby channel, and Eqd principal is an equalization delay signal corresponding to the primary channel; and Eqd standby and Eqd primary mentioned below are both the same as above in meaning, which is not repeated.
When protection switching is switched from the standby channel to the primary channel, step 102 specifically comprises: a current equalization delay signal corresponding to the primary channel is obtained according to the RTD Δ and an equalization delay signal corresponding to the standby channel before, and the equalization delay signal is updated. At this moment, the formula of Eqd primary =Eqd standby +RTD Δ can be adopted.
The other situation is that protection switching is not triggered when the ONUs are in a normal working state.
Step 101 specifically comprises: under the condition that the ONUs are in a normal working state, measurement can be performed in advance, so that an updated equalization delay signal can be adopted directly when a failure results in the triggering of protection switching. As soon as the time arrives, the OLT distributes the RTD Δ to all the ONUs in the form of a broadcast message.
A specific processing procedure of step 102 can comprise the following steps.
Step 1021 a : a current equalization delay signal corresponding to the standby channel is obtained in advance according to the RTD Δ and the prior equalization delay signal corresponding to the primary channel, and a management information base is updated. At this moment, the formula of Eqd standby =Eqd primary +RTD Δ can be adopted.
Step 1022 a : when the protection switching from the primary channel to the standby channel is triggered, the updated equalization delay signal is enabled.
Another specific processing procedure of step 102 can comprise the following steps.
Step 1021 b : a current equalization delay signal corresponding to the primary channel is obtained in advance according to the RTD Δ and the prior equalization delay signal corresponding to the standby channel, and a management information base is updated. At this moment, the formula of Eqd primary =Eqd standby +RTD Δ can be adopted.
Step 1022 b : when the protection switching from the standby channel to the principal channel is triggered, the updated equalization delay signal is enabled.
It should be pointed out that the broadcast message mentioned above comprises a modified Ranging_time message or a custom dedicated message.
Wherein the format of the modified Ranging_time message is shown in table 1 below:
TABLE 1
Ranging_time message
Content of
Byte
the byte
Meaning of the byte
1
ONU
As a unicast message, it is set into ONU-ID here,
identification
and the value of ONU-ID is unequal to 0xFF.
or 11111111
As a broadcast message distributed to all the
ONUs, it is set into 0xFF here.
2
00000100
It indicates that the message type is
‘Ranging_time’
3
00000cab
a: ‘0’—the content of bytes 4 to 7 is EqD.
‘1’—the content of bytes 4 to 7 is RTD Δ .
b: ‘0’—indicats that the parameter included in the
message is EqD of the primary channel.
‘1’—indicats that the parameter included in the
message is EqD of the standby channel.
c: it is valid when the value of a is 1, which
indicates the positive and negative of RTD Δ .
0—indicates negative value;
1—indicates positive value.
4
dddddddd
Top bit of EqD or RTD Δ
5
dddddddd
6
dddddddd
7
dddddddd
Lowest bit of EqD or RTD Δ
8-12
Unspecified
Here, what should be point out about table 1 is as follows: firstly, when byte 1 is set into 0xFF, bytes 4 to 7 contains the absolute value of the RTD Δ ; when byte 1 is set to be unequal to 0xFF, bytes 4 to 7 contains the value of EqD or RTD Δ , and the positive and the negative of the value are identified with indicator bit a in byte 3; secondly, the unit of EqD or RTD Δ is bit; and thirdly, the Ranging_time message is used for distributing EqD of a working channel and that of a protection channel, or RTD Δ applied to the protection switching process to the ONUs. Besides, bytes 8 to 12 in table are is unspecified, which indicate reserved bit that is not specified or explained.
If the modified Ranging_time message shown in table 1 is adopted, when the first byte is 0xFF, the message is a broadcast message, but when the first byte is not equal to 0xFF, the message is a unicast message. The third byte is an indicating bit, and the 4 th to 7 th bytes are filled with specific indication content according to the indication of the indicating bit.
If a custom dedicated message is adopted, then the parameter RTD Δ is transmitted to the ONU through a newly-defined PLOAM message.
In sum, the disclosure mainly comprises that the disclosure is not limited to the network structure shown in FIG. 2 , and the OLT may comprise at least one primary channel and/or at least one standby channel. In the disclosure, the method for quickly updating ranging results of the ONUs can be used for switching from the primary channel to the standby channel as well as switching from the standby channel to the principal channel.
In the prior art, if the protection mode is triggered, all the ONUs need to be switched to the channel corresponding to the standby OLT. Each ONU is required to update the equalization delay signal and can continue working normally after being regulated to be logically equidistant to the standby OLT so as to avoid conflict on the uplink. The standby OLT calculates the equalization delay signal corresponding to each ONU mainly based on the ranging process defined in the existing standard, namely the value of the round trip delay between the ONU and the OLT. Accordingly, both the primary channel and the standby channel of each ONU have corresponding values of the round trip delays, namely, RTD primary and RTD standby . In the trunk optical fiber protection mode, the difference RTD Δ between the RTD primary and the RTD standby is the same to all the ONUs and is related to a trunk optical fiber length difference between the primary channel and the standby channel, namely fiber length difference between the OLT and the optical splitter, and unrelated to a fiber length of a branch fiber, namely fiber length between the optical splitter and the ONUs; besides, RTD Δ =RTD primary −RTD standby . Therefore, in the trunk optical fiber protection mode, the RTD Δ is the same to all the ONUs. In the prior art, the OLT originally needs to calculate the equalization delay signal corresponding to each ONU according to the RTD Δ , and then distributes the equalization delay signal corresponding to each ONU to the corresponding ONU through a one-to-one communication mode; however, in the disclosure, the RTD Δ is the same to all the ONUs, the RTD Δ can be obtained from the OLT through a one-to-all communication mode, and then each ONU can calculate the equalization delay signal corresponding to the ONU itself, wherein the calculation formula is derived as follows, and the formula of Eqd standby =Eqd primary +RTD Δ is derived. In the formula below, T eqd is a fixed value set by the OLT.
Eqd standby =T eqd −[RTD primary −RTD Δ ]
RTD primary =T eqd −Eqd primary
Eqd standby =T eqd −[T eqd −Eqd primary −RTD Δ ]=Eqd primary +RTD Δ
Here, it should be pointed out that Eqd principal is a parameter used by the ONU before protection switching is performed, and the ONU can still acquire the value after is protection is triggered to be switched into the standby channel, wherein the value is stored in the ONU. For the RTD Δ , in the trunk optical fiber protection mode, the RTD Δ is the same to all the ONUs. Therefore, the OLT can distribute the parameter RTD Δ of EqD corresponding to each ONU originally calculated in the OLT to each ONU in the form of a broadcast PLOAM message, and each ONU can calculate the Eqd parameter of a standby channel corresponding to each ONU according to the formula of Eqd standby =Eqd primary +RTD Δ .
Embodiment 1
an ONU is in a ranging state after protection switching is triggered. In the embodiment, the process of quickly updating ranging results of the ONUs specifically comprises the following steps.
Step 201 : when in an O4 state, namely in a ranging state, an ONU wait for a corresponding equalization delay signal sent by a standby OLT.
Step 202 : the standby OLT acquires RTD Δ related to a trunk optical fiber length difference between a primary channel and a standby channel according to the prior art.
Step 203 : the OLT transmits a Ranging_time message modified for three times to all the ONUs in the form of a broadcast message, wherein the Ranging_time message comprises the RTD Δ .
Step 204 : the ONU calculates an equalization delay signal corresponding to the standby channel through the formula of Eqd standby =Eqd primary +RTD Δ according to the RTD Δ included in the received Ranging_time message and an equalization delay signal corresponding to the primary channel which is used by the ONU originally.
Here, the equalization delay signal corresponding to the primary channel is the equalization delay signal locally stored in the ONUs before and used originally before protection switching is performed. The equalization delay signal stored before is updated through the calculated equalization delay signal corresponding to the standby channel, so that quick updating of ranging results can be implemented. On the basis of quick updating of ranging results, the time requirement of service switching can be satisfied, so that protection switching can be accomplished quickly.
Step 205 : after quick updating of ranging results is implemented and protection switching is accomplished, the ONUs enter an O5 state, namely enter a normal working state.
In the prior art, before the switching of the standby channel of the standby OLT and an ONU is not enabled, ranging of the standby channel is carried out in the normal working state of the ONU, so that the RTD Δ can be acquired. Therefore, related parameters can be transmitted to the ONUs through the modified PLOAM message in a normal working state of the ONU, and the EqD for the standby channel can be calculated.
Embodiment 2
when an ONU is in a normal working state, and protection switching is not triggered at this moment, a management information base is updated in an update mode of broadcast RTD Δ , so that an updated equalization delay signal can be adopted directly when protection switching is started. In the embodiment, the process of quickly updating ranging results of the ONUs specifically comprises the following steps.
Step 301 : when an ONU is in an O5 state, namely in a normal working state, a standby OLT acquires RTD Δ related to a trunk optical fiber length difference between a primary channel and a standby channel according to the prior art.
Step 302 : the OLT transmits a Ranging_time message modified for three times to all the ONUs in the form of a broadcast message, wherein the Ranging_time message comprises the RTD Δ .
Step 303 : the ONU calculates an equalization delay signal corresponding to the standby channel through the formula of Eqd standby =Eqd primary +RTD Δ according to the RTD Δ included in the received Ranging_time message and an equalization delay signal corresponding to the primary channel used by the ONU originally.
Step 304 : the ONU updates the equalization delay signal corresponding to the standby channel in a management information base; and after protection switching is started, the updated equalization delay signal corresponding to the standby channel is enabled.
Embodiment 3
when ONUs are in a normal working state, and protection switching is not triggered at this moment, a management information base is updated in an update mode of a unicast EqD, so that an updated equalization delay signal can be adopted directly when protection switching is started. In the embodiment, the process of quickly updating ranging results of ONUs specifically comprises the following steps.
Step 401 : when an ONU is in an O5 state, namely in a normal working state, a standby OLT acquires RTD Δ related to a trunk optical fiber length difference between a primary channel and a standby channel according to the prior art.
Step 402 : the OLT calculates an equalization delay signal of each ONU corresponding to the standby channel, and transmits a Ranging_time message modified for three times to each ONU in the form of a unicast message, wherein the Ranging_time message comprises an equalization delay signal corresponding to each ONU calculated by the OLT.
Step 403 : the ONU receives the unicast Ranging_time message and parses out the equalization delay signal included in the Ranging_time message and corresponding to the standby channel of the ONU.
Step 404 : the ONU updates the equalization delay signal corresponding to the standby channel in a management information base; and after protection switching is started, the updated equalization delay signal corresponding to the standby channel is enabled.
A system for quickly updating ranging results of ONUs by an OLT comprises a distributing unit and an updating unit, wherein the distributing unit is used for distributing an acquired ranging difference to all the ONUs by the OLT, and the updating unit is used for implementing quick updating of ranging results of the ONU itself according to the acquired ranging difference by the current ONU.
Here, the distributing unit is further used for distributing acquired RTD Δ to all the ONUs by the OLT, wherein the RTD Δ is a round trip delay ranging difference between a primary channel and a standby channel.
Since the ONUs acquire the RTD Δ at different times, specific implementation of the distributing unit and the updating unit is different, which is elaborated in two situations below.
One situation is that the ONUs are in a ranging state after protection switching is triggered.
The distributing unit is further used for distributing the RTD Δ to all the ONUs in the form of a broadcast message by the OLT under the condition that the ONU is in a ranging state after protection switching is triggered.
The updating unit is further used for obtaining a current equalization delay signal corresponding to the standby channel according to the RTD Δ and an equalization delay signal corresponding to the primary channel before under the state of switching from the primary channel to the standby channel, and updating the equalization delay signal; and the formula of Eqd standby =Eqd primary +RTD Δ can be adopted; or
the updating unit is further used for obtaining a current equalization delay signal corresponding to the primary channel according to the RTD Δ and an equalization delay signal corresponding to the standby channel before under the state of switching from the standby channel to the primary channel, and updating the equalization delay signal; and the formula of Eqd primary =Eqd standby +RTD Δ can be adopted.
The other situation is that the ONUs are in a normal working state.
The distributing unit is further used for distributing the RTD Δ to all the ONUs in the form of a broadcast message by the OLT under the condition that the ONU is in a normal working state.
The updating unit is further used for obtaining a current equalization delay signal corresponding to the standby channel in advance according to the RTD Δ and an equalization delay signal corresponding to the primary channel before, and updating a management information base; and enabling the updated equalization delay signal after the protection switching from the primary channel to the standby channel is triggered. The formula of Eqd standby =Eqd primary +RTD Δ can be adopted; or
the updating unit is further used for obtaining a current equalization delay signal corresponding to the primary channel in advance according to the RTD Δ and an equalization delay signal corresponding to the standby channel before, and updating a management information base; and enabling the updated equalization delay signal after the protection switching from the standby channel to the primary channel is triggered. The formula of Eqd primary =Eqd standby +RTD Δ can be adopted.
The value of the Round Trip Delay mentioned above is abbreviated as RTD; and the equalization delay signal is abbreviated as EqD.
All the above are only preferred embodiments of the disclosure but not limits the protection scope of the disclosure. | The disclosure provides a method for quickly updating ranging results of optical network units by an optical line terminal. The method comprises the following steps: an Optical Line Terminal (OLT) distributes an acquired ranging difference to all the Optical Network Units (ONUs); and the current ONU implements quick updating of the ranging result of the current ONU itself according to the acquired ranging difference. The disclosure also provides a system for quickly updating ranging results of ONUs by an OLT, wherein a distributing unit in the OLT is used for distributing an acquired ranging difference to all the ONUs; an updating unit in the ONU is used for implementing quick updating of ranging result of the current ONU itself according to the acquired ranging difference. the method and system of the disclosure can save the quantity of messages, enable quick switching in protection status, thus implementing protection switching efficiently. | 7 |
CLAIM OF PRIORITY
[0001] This application claims priority of prior provisional Application Ser. No. 60/631,950 filed Nov. 30, 2004, the entire content of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates generally to medicine containers, and more particularly to a dosage reminder cap for prescription medicine containers providing an indication of when the next dose of medicine is due and facilitating tracking of the last dose dispensed from the container.
BACKGROUND AND SUMMARY OF THE INVENTION
[0003] All prescription medications are accompanied by a doctor's directions for the frequency and amount of each dose to be consumed by a patient. Many medications must be taken daily in order to be effective, some at multiple intervals during the day. Other medications are only taken as needed, but a patient or care giver needs to know when the last dose was taken to prevent over-dosing. Some of the hazards associated with incorrect consumption, commonly called noncompliance, of medications include prolonged illness, ineffectiveness of the medicine, hospitalization, commitment into a nursing home facility, and death. All of the aforementioned hazards eventually result in increased health care costs to patients and society as a whole.
[0004] Several medicine dose tracking devices are currently available to consumers. Some comprise a container with compartments for multiple doses per day of the week. Others provide an indicator for each day of the week, either on the container closure or on a label placed inside the container whereby each dose of medicine is sealed in an individual packet and dispensed by pushing through a layer of foil. Other devices track the number of times a container has been opened. Each of these devices has limitations.
[0005] Devices that track only the day of the week do not provide any way to track multiple doses per day, unless the medicine is packaged in a foil-lined packet. A foil-lined packet with multiple doses per day is impractical when there are two or more doses per day, because a prescription for longer than a few days requires a package of considerable size, even for the smallest of pills.
[0006] Multiple compartment containers allow patients to place multiple medications together or single, multiple-dose medications into compartments according to the number of doses per day. Although such containers are common, they violate the legal requirement that medications must be stored in properly labeled containers. In addition to the labeling requirement, there are no child safety features and no remedy for displacement of medication, for example falling out of the container; mixing of the doses of medication; or incorrectly dispensing the medication into the container.
[0007] Devices that track the number of times a container is opened present several difficulties. Devices currently available do not provide for opening the container and not taking a dose. Further, there is nothing to help track when the last dose was taken or when the next dose is due, and no way of tracking the quantity of medicine dispensed when the container was opened. In addition to the dosage tracking limitation, available container caps and other constructions are generally round in shape, which do not prohibit the container from rolling off of the surface upon which it was placed.
[0008] The present invention comprises a dosage reminder cap which overcomes the foregoing and other difficulties which have long since characterized the prior art. In accordance with the broader aspects of the invention, a dosage reminder cap contains a dial which is rotated and set to indicate either the last day and dose when the medication was taken or when the next dose is due.
[0009] In accordance with more specific aspects of the invention, a dosage reminder cap for a medicine container comprises a hexagonal shape with each day of the week and multiple doses per day displayed thereon. A round disk with a small window cutout (window disk) is recessed into the hexagonal cap and is affixed therein. The user rotates the window disk clockwise until the desired day and dose is revealed through the window.
[0010] The hexagon shape of the cap prevents the container from rolling and falling off the surface upon which it was placed. The hexagon shape also makes the cap easier to grip and therefore easier to open. The cap is further equipped with a child safety feature for deterring a child from removing the cap from the container and thereby gaining access to the contents thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A more complete understanding of the present invention may be had by reference to the following Detailed Description when taken in connection with the accompanying Drawings, wherein:
[0012] FIG. 1 is a perspective view of a dosage reminder cap comprising a first embodiment of the present invention;
[0013] FIG. 2 is an exploded perspective view of the dosage reminder cap shown in FIG. 1 ;
[0014] FIG. 3 is a section view taken along the line 3 - 3 in FIG. 2 ;
[0015] FIG. 4 is perspective view of one component of the dosage reminder cap shown in FIG. 1 ;
[0016] FIG. 5 is a sectional view taken along the line 5 - 5 in FIG. 1 ;
[0017] FIG. 6 is a perspective view of a dosage reminder cap comprising a second embodiment of the present invention; and
[0018] FIG. 7 is an exploded perspective view of the dosage reminder cap shown in FIG. 6 .
DETAILED DESCRIPTION
[0019] Referring now to the drawings, and particularly to FIG. 1 thereof, there is shown a medicine container 20 having a dosage reminder cap 22 installed thereon. The dosage reminder cap 22 comprises a hexagon shaped base 24 and a window disk 26 . The dosage reminder cap 22 threadedly engages the top of the container 20 until it rests upon a lip 28 around the container 20 . The lip 28 has a detent 30 and a tab 31 on one side thereof providing a child safety feature.
[0020] Referring to FIG. 2 , there is shown an enlarged, exploded view of the embodiment shown in FIG. 1 . The dosage reminder cap 22 fastens onto the container 20 by engaging a threaded neck 32 of the container 20 . A notch 34 formed in the base 24 engages the detent 30 and locks the dosage reminder cap 22 in place. In order to unscrew and remove the dosage reminder cap 22 , the tab 31 is pressed down enabling the base 24 to disengage the detent 30 . The base 24 is thereafter pressed down and turned in a counterclockwise direction at the same time.
[0021] The hegaxon shaped base 24 comprises a cavity 36 in the top center therof which is sized to accommodate the window disk 26 recessed therein. Printed within the cavity 36 are two concentric text rows 38 and 40 . The outer row 38 has each of the seven days of the week spaced at equal intervals therearound. The inside row 40 comprises sets of sequential numbers located below, concentric with and aligned with each day of the week displayed in the outer row 38 , each set of numbers beginning with the number 1. In the center of the cavity 36 is an opening 42 for accommodating a pin 44 protruding from the bottom of the window disk 26 . The pin 44 snaps into the opening 42 thereby securing the window disk 26 to the base 24 and providing the axis about which the window disk 26 turns.
[0022] The window disk 26 has a T-shaped window 50 cut out of one edge thereof. The window 50 displays one day of the week from the outer row 38 and one number from the inner row 40 . Below the window 50 is indicator text 52 to assist the patient or person dispensing the medicine. The text 52 comprises the words “Last Dose Taken.” Alternative texts are “Next Dose Due”, “Next Dose To Be Taken”, or other alternative phrases having similar meanings.
[0023] The window disk 26 rotates counterclockwise and stops when the desired day and dose number are displayed through the window 50 . A series of notches 54 are formed in the face of the cavity 36 , such that there is one notch 54 for each corresponding dose number of the inner row 40 . The notches 54 engage a triangular wedge 56 protruding from the bottom of the window disk 26 thereby locking the window disk 26 in place when the desired day and dose number are displayed through the window 50 . To change the day and dose number displayed, a person dispensing the medicine turns the window disk 26 by pressing down in the disk with a thumb or other finger.
[0024] Referring now to FIG. 3 , there is shown the engagement of the wedge 56 and the notches 54 . The wedge 56 and the notches 54 have the shape of an isosceles triangle. The isosceles triangle shape allows the wedge 56 to continue forward to the next notch 54 while preventing the wedge 56 from going back to the previous notch 54 .
[0025] Referring now to FIG. 4 , there is shown a view of the bottom of the window disk 26 illustrating the location of the pin 44 and the wedge 56 .
[0026] Referring now to FIG. 5 , the dosage reminder cap 22 is shown secured in engagement with the container 20 . The inner surface of the base 24 is threaded to engage corresponding threads 58 of the neck 32 of the container.
[0027] FIGS. 6 and 7 illustrate a dosage reminder cap 60 comprising a second embodiment of the invention. Many of the component parts of the dosage reminder cap 60 are substantially identical in construction and function to component parts of the dosage reminder cap 22 illustrated in FIGS. 1 through 5 and described hereinabove in conjunction therewith. Such identical component parts are designated in FIGS. 6 and 7 with the same reference numerals utilized above in the description of the dosage reminder cap 22 , but are differentiated therefrom by means of a prime (′) designation.
[0028] The dosage reminder cap 60 differs from the dosage reminder cap 22 in that the dosage reminder cap 60 employs an alternative closure and child safety mechanism for engagement with the container 20 ′. The base 24 ′ of the dosage reminder cap 60 comprises two locking tabs 62 on opposite sides for engagement with a lip 63 of the container 20 ′. A circular inner surface 64 of the base 24 ′ secures over the neck 32 ′ of the container 20 ′.
[0029] As shown in FIG. 7 , to remove the dosage reminder cap 60 from the container 20 ′ pressure is applied to two pressure points 68 equidistant between the tabs 62 on opposite sides of the base 24 ′. As pressure is applied to the pressure points 68 , the tabs 62 are forced outwardly thereby disengaging the tabs 62 from the lip 63 allowing the dosage reminder cap 60 to removed from the container 20 ′.
[0030] Although preferred embodiments of the invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications, and substitutions of parts and elements without departing from the spirit of the invention. | A dosage reminder cap provides an easy, effective way to track consumption of medication. A rotating disk provides a tool for marking the either last dose taken or the next dose due to be taken of a prescribed medication in order to facilitate proper consumption of the medication. | 0 |
This invention claims priority from provisional application Ser. No. 61/262,912, filed Nov. 19, 2009.
BACKGROUND OF THE INVENTION
This invention relates generally to methods and apparatus utilized in the completion of hydrocarbon wells, and is particularly directed to methods for reducing the amount of drillrig time and associated expense associated with hanging casing or tubing within a previously installed concentric outer casing.
A hydrocarbon well typically employs a plurality of tubular or concentric casing strings extended from the ground surface toward the subsurface hydrocarbon reservoir, with the outermost string having the largest diameter and being the shortest in length, with each inner string having a smaller diameter and a longer length. The outermost pipe, the conductor pipe, is installed as part of site preparation and will be present when the drilling rig moves onto the location. The conductor pipe typically extends from a depth of 20 to 100 feet, and will have a diameter of 4 inches or larger. A starting head/drilling rig is attached to the top of the conductor pipe for connecting to blowout prevention equipment, i.e. BOP and typically a diverter. The casing head typically on the surface casing will usually have an internal shoulder.
Once moved on location, the drilling rig drills to the surface/next casing point, which is a predetermined depth set below freshwater bearing zones, or difficult strata such as sloughing clay or gravel zones. Typically, this first casing point extends from a few hundred to a thousand feet below ground surface. Once the first casing point is reached, the surface casing is run into the well, and cemented in place, usually by pumping cement down through the inside of the casing, and continuing to pump until the cement exits the bottom of the casing and circulates up into the annulus between the open hole and the outside of the surface casing.
Once cementing operations have been completed on the surface casing and the cement adequately hardened, a blowout preventer (BOP) stack is nippled down and removed from under the rig. The drilling rig is cut off and removed. The surface casing is cut and dressed to land/install a surface casing well head. A BOP is re-installed and attached or nippled up to the casing head. Drilling thereafter continues, until the next casing point is reached, at which time a smaller string of casing is run into the well. Depending upon the integrity of the drilled strata and the anticipated depth of the well, the casing point may extend all of the way to the production zone, and production casing installed. Alternatively, one or more intermediate strings of casing may be concentrically installed within the surface casing. The production casing typically extends from the ground surface to the production zone which may be thousands of feet down. In some cases, the production casing is hung or attached to the bottom of the surface casing, or intermediate casing.
The production casing is cemented in place, and after all of the cement has been pumped into place, the casing string is held stationary while the cement sets up. Thereafter, a slip-type casing hanger is placed around the top joint of the production casing, which is typically landed against an internal shoulder of a casing spool or newly attached wellhead.
In well completions the casing is preferably hung in tension to reduce the possibility of casing collapse. Such collapse is possible when the top of the casing is locked into position within the wellhead. For example, if the well is subject to thermal stimulation, the casing will expand and place the casing string into buckling, because the top of the casing is locked in place at the wellhead.
In most applications, before landing the surface casing, production casing string, or intermediate casing string, it is necessary to remove the blowout preventer stack to land the casing string within a well head spool at wellhead. Removal of the blowout preventer stack is time consuming, and requires a drilling rig to sit idle for hours while the stack is removed, the casing spool or wellhead attached, and the blowout preventers nippled back up. Because of the relatively high expense for rig time, this delay is expensive. In addition, if the well proves to be productive, the wellhead and casing hanging equipment utilized in this procedure are permanently installed in the well. These devices are usually expensive and add substantially to the expense of the well.
SUMMARY OF THE INVENTION
It is a major object of the invention to provide method and apparatus to meet needs associated with the above described operations. Basically, the method of installing a plurality of casing sections in a well, includes the steps
a) providing a hanger supporting the casing sections to extend longitudinally in the well, b) landing the hanger on structure in the well, whereby weight of the casing sections longitudinally compresses the hanger, c) cementing casing sections in position in the well, below the hanger, d) adjusting the hanger to provide for controllable longitudinal shortening of hanger length, thereby removing exertion of casing weight on the hanger, e) and removing at least part of the hanger away from the well head.
In one mode, the d) and e) steps may include:
d) adjusting the hanger to allow controllable expansion of at least a portion of the hanger and longitudinal shortening of hanger length in response to relief of hanger generally sideward compression, e) and removing at least said expanded portion of the hanger from the well.
As will be seen, the hanger may typically have interengaged wedge surfaces that interengage to induce lateral expansion of the hanger portion. Also, such wedge surfaces preferably extend angularly laterally and longitudinally, and define upper and lower interengaged surfaces, as for example with V-shape, and/or converted V-shaped.
A further object includes provision for use of a hanger that has an expansible wall portion on which at least one of such wedge surfaces is located. Retention means is typically provided and used for blocking the wall portions against expansion, and is adjustable to allow unblocking of lateral expansion of the hanger.
Yet another object includes the step of severing the upper portion of the hanger from a lower mandrel portion of the hanger, to allow removing of the upper portion of the hanger from the well. In this method, lateral expansion of the hanger serves to facilitate removal of the upper portion of the hanger from the well. The mandrel is typically landed prior to such severing, in supporting relation to the wedge surfaces, to allow their relative sliding.
Accordingly, the present method and apparatus are directed toward eliminating the need to lock the top of a casing into a wellhead, as well as the need to remove and reinstall a blowout preventer stack as part of the process in landing a string of casing joints within a hydrocarbon well, where the casing is to be cemented in place. Attached to the last joint of the string run into the well is a hanger, embodiments of which are disclosed herein. The hanger is landed onto a load shoulder, or other structure installed within or upon the uppermost joint of the previously installed string of casing outside of the string being installed.
The method and apparatus allow the utilization of an alternative assembly, as disclosed, for attachment of the blowout preventer, although the conventional assembly may also be utilized. Installation of the equipment may take place after the hanging of the casing using an embodiment of the disclosed hanger. A diverter spool may be made up directly to the top of the conductor pipe, with the blowout preventer made up to the diverter spool. The hanger and casing may be hung and cemented in place below the mandrel load shoulder of the lower bowl, with cement return taken through the diverter spool. After the cement has hardened, the blowout preventer may be removed and the wellhead installed, with the casing already landed and cemented in place.
In contrast to known casing hangers, the hanger utilized in the present method typically and preferably comprises length adjustment means, where the hanger is adjustable between a first length and a second length, and where the first length is longer than the second length. The casing string is suspended from the hanger, and the hanger, in turn, is suspended within the well. Cement is thereafter circulated within the well, whereby the cement forms a sheath around a portion of the casing string, and the casing is typically in tension. After the cement is allowed to reach a predetermined strength, the hanger is adjusted to second length, after which tension on the casing string is released, the top of the casing not being rigidly locked into place. Because the disclosed hanger is landed within the uppermost joint of the previously installed casing strings, there is no need to nipple down the blowout preventer.
A further object is to provide axially exerted force acting on the hanger, by one of the following:
i) axially extending bolts exerting force on axially spaced hanger sections, ii) axially extending hydraulic ram structure exerting force on axially spaced hanger sections, iii) axially extending jacking structure exerting force on axially spaced hanger sections.
While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. Thus the scope of the invention should not be limited according to these factors, but according to the claims to be filed in the forthcoming utility application.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an isometric view of a casing hanger;
FIG. 2 shows a side view of the casing hanger shown in FIG. 1 ;
FIG. 3 shows a front view of the casing hanger shown in FIG. 1 ;
FIG. 4 shows a top view of the casing hanger shown in FIG. 1 ;
FIG. 5 is a section taken on lines 5 - 5 of FIG. 2 ;
FIG. 6 shows a side view of the hanger supporting well casing;
FIG. 7 shows a front view of the FIG. 6 hanger and casing shown in FIG. 5 ;
FIG. 8 is a section taken on lines 8 - 8 of FIG. 6 ;
FIG. 9 shows an isometric view of an upper wedge member of the hanger;
FIG. 10 shows a side view of the wedge member as shown in FIG. 9 ; and FIG. 10 a is a section taken on lines 10 a - 10 a of FIG. 10 ;
FIG. 11 shows a front view of the wedge member as shown in FIG. 9 ;
FIG. 12 shows a top view of the wedge member as shown in FIG. 9 ;
FIG. 13 shows an isometric view of an intermediate wedge member of the casing hanger;
FIG. 14 shows a side view of the intermediate wedge member shown in FIG. 13 ;
FIG. 15 shows a top plan view of the top wedge member of FIG. 13 ;
FIG. 16 shows a top plan view of one section of the two sections wedge member of FIG. 15 ;
FIG. 17 shows an isometric view of the bottom wedge member of the casing hanger;
FIG. 18 shows a side view of the bottom wedge member, seen in FIG. 17 ;
FIG. 19 shows a front view of the bottom wedge member shown in FIG. 17 ;
FIG. 20 shows a top view of the bottom wedge member shown in FIG. 17 ;
FIG. 21 is a section taken on lines 21 - 21 of FIG. 18 ;
FIG. 22 shows an isometric view of a mandrel section of the casing hanger;
FIG. 23 shows a side view of the mandrel section seen in FIG. 22 ;
FIG. 24 shows a front view of the mandrel section shown in FIG. 22 ;
FIG. 25 shows a top view of the mandrel section shown in FIG. 22 ;
FIG. 26 shows the hanger of FIG. 6 with the upper section dropped down;
FIG. 26 ′ is a schematic view of structure seen in FIG. 26 ;
FIG. 27 shows a front view of the hanger of FIG. 26 ;
FIG. 28 is a section taken on lines 28 - 28 of FIG. 27 ;
FIG. 29 shows a top view of top wedge member seen in FIG. 27 , and which may be utilized in the FIG. 26 hanger;
FIG. 30 is an isometric view of the FIGS. 26-18 shortened hanger;
FIG. 31 shows a modified form of hanger shortening apparatus; and FIG. 31 ′ shows the FIG. 31 apparatus in adjusted state;
FIG. 32 is a side view of the FIG. 31 apparatus;
FIG. 33 is a section taken on lines 33 - 33 of FIG. 32 ;
FIG. 34 is a top plan view of the FIG. 32 apparatus;
FIGS. 35 , 36 and 37 correspond to FIGS. 32. 33 and 34 , but after hanger shortening as in FIG. 31 ′;
FIGS. 38-40 correspond to FIGS. 32-34 , but show another modified hanger apparatus, prior to shortening;
FIG. 41 is an isometric view of the FIGS. 32-34 apparatus;
FIG. 41 ′ shows the FIG. 41 apparatus after shortening;
FIGS. 42-44 correspond to FIGS. 38-40 , showing the hanger after shortening;
FIGS. 45-47 correspond to FIGS. 30-40 and show another modified hanger, prior to shortening;
FIG. 48 is an isometric view of the FIGS. 45-47 hanger apparatus;
FIG. 48 ′ shows the FIG. 48 apparatus after shortening;
FIGS. 49-51 correspond to FIGS. 45-47 , but show the apparatus after shortening;
FIGS. 52-56 are an isometric view, side views, a section view, and a top view of a bowl unit that receives the lower sealing element seen in FIGS. 2 and 3 ;
FIGS. 57-61 correspond to FIGS. 52-56 , but show a modification, and show a sealing element seated at lower bowl;
FIG. 62 shows a double hung casing installation; and
FIG. 63 shows slidable mandrel sealing.
DETAILED DESCRIPTION
Referring first to FIGS. 6 and 26 , they show hanger 99 upper, lower and intermediate members 110 , 111 and 112 prior to ( FIG. 6 ) and after ( FIG. 26 ) lateral translation or expansion of intermediate member 112 relative to upper and lower members 110 and 111 . Simplified schematic view 26 ′ corresponds to FIG. 26 . Such lateral translation is facilitated by sliding slippage of upward facing upper V-shaped wedge surfaces 111 a and 111 b on member 111 , relative and with respect to downward facing upper V-shaped wedge surfaces 110 a and 110 b on 110 ; and simultaneous sliding slippage of downward facing lower inverted V-shaped wedge surfaces 111 c and 111 d relative and with respect to upward facing lower inverted V-shaped wedge surfaces 112 c and 112 d on 112 . This enables downward bodily displacement of 110 relative to and beneath wall casing 103 flange or shoulder 103 a previously landed on the top 99 a of hanger 99 , the casing then connected in position in the well, whereby casing loading on the shortened hanger is relieved. This in turn enables sideward and outward removal of meshing 110 and 111 from beneath member 99 .
Note, that member 111 is in two sections, 111 e and 111 f held in FIG. 6 position (prior to lateral displacement) by a fastener device or devices, such as bolts 102 that extend horizontally between the sections 111 e and 111 f . Upon loosening of those bolts, the downwardly composed weight effects member sliding, as referred to. A further advantage of this V-shaped configuration of sliding surfaces is the maintenance of vertical alignment of the members 110 - 112 , precluding interference with well structure, at the side or sides of the hanger structure. Angularity of the V-shaped member surfaces is typically about 30° relative to horizontal.
Centering guides 96 and 97 on 99 and 111 serve to center the hanger in position at the well head.
Accordingly, the members 99 , 110 and 111 are then easily removed, and the mandrel 20 below and supporting member 111 is upwardly removed, whereby the hanger is removed, from support at 106 , leaving the casing 103 projecting upwardly in the top well zone 107 . Support shoulder 106 is typically provided by outer casing in the well. Accordingly, means is provided whereby the hanger is expanded laterally and lengthwise shortened, in response to disconnection of hanger elements, such as bolt 102 and in response to imposed casing weight, facilitating ease of removal of the hanger from the top zone of the well.
Referring now to FIGS. 1-8 , the hanger 99 is generally tubular, and is shown in its first length configuration. It may be adjusted to its second and shortened length by loosening the bolts 102 that clasp together flanges 12 a on the two sections of 111 , at opposite sides of axes 90 . The intermediate wedge member sections slide laterally oppositely along diagonal upper and lower surfaces as referred to and sections 111 c and 111 d move radially outwardly. The casing hanger moves to shortened position. The casing hanger 99 may further comprise the lower supporting mandrel 20 having rubber O-rings 20 a to seal against casing bore, or outer conductor casing. See bore 150 in FIGS. 2 and 5 . Mandrel 20 may be left in the well to provide a seal in the annulus between the casing being hung with the casing hanger 99 and the previously installed casing string, in which the casing hanger is suspended. The mandrel is typically bolted to hanger section 112 . FIGS. 2 and 27 show hanger length dimensions A and B, before and after hanger adjustment, below casing flange 103 a.
As shown in the Figures and described, the intermediate section 111 , is of split construction 111 e and 111 f which allows the hanger to be taken apart in place in sections, facilitating removal of the hanger from the cemented casing or tubing, and below casing flange 103 a.
Referring now to FIGS. 31-37 , they show an alternative form of the hanger 126 that employs vertical bolts or fasteners 125 rotatable to shorten the hanger length as from a long measurement A (see FIG. 32 ) to a short measurement B (see FIG. 35 ). This lowers the casing flange support shoulder 126 ′ on the top of the hanger by amount A-B below the casing flange 103 a , relieving energy or tension in the initially hanger supported casing 103 . Bolts 125 can easily be removed to allow removal of the hanger upper and lower elements 110 ′ and 111 ′ described above. Upper element 110 ′ is spaced above element 111 ′. Bolt adjustment moves bolt flange 110 a ′ toward bolt flange 111 a ′ on 111 a .
FIGS. 31 and 31 ′ show the hanger prior to after its axial shortening.
FIGS. 38-44 correspond to FIGS. 31-37 , respectively, and show another alternative form of the hanger 127 and that employs two or more hydraulic rams, instead of adjustable bolts, for shortening hanger 127 length as from long measurement A (see FIG. 38 ) to a short measurement B (see FIG. 42 ). As before, this lowers the casing flange support shoulder 127 ′ on the top of the hanger, by amount A-B below the casing flange 103 a , thereby relieving energy or tension in the initially hanger suspended casing 103 . The hydraulic rams include pistons 135 connected to upper hanger element 310 , and projecting downwardly in cylinders 136 connected to lower hanger element 312 . Pressurized fluid in the cylinders at 313 is controllably relieved by valve means 314 to allow element 310 to be lowered, shorten the hanger. Valve means 314 ′ controls fluid pressure input to 336 . FIGS. 41 and 41 ′ show the hanger prior to and after its axial shortening.
FIGS. 45-51 , correspond to FIGS. 38-44 respectively, and show a further alternative form of the hanger 140 , and that employs an hydraulic jack type means, instead of adjustable bolts or multiple hydraulic rams, for shortening the hanger 140 length, as from a long measurement A (see FIG. 45 ) to a short measurement B (see FIG. 49 . This lowers the casing flange support shoulder 140 ′ on the top of the hanger, by amount A-B below the casing flange 103 a , relieving energy or tension in the initially hanger suspended casing 103 . The jack means includes a cylindrical piston 145 connected to upper hanger element 140 ′, and projecting downwardly in the cylinder 146 connected to hanger lower element 147 , corresponding to 112 . Pressurized fluid in the cylinder space 148 is controllably relieved by valve means 149 to allow element 140 to be lowered to shorten the hanger allowing upward removal of 140 ′, 146 and 147 . FIGS. 48 and 48 ′ show the hanger prior to and after axial shortening.
FIGS. 52-56 show a retrievable lower bowl assembly 270 which is of generally cylindrical configuration to receive the hanger lower sealing element, as shown at 20 in FIG. 6 , for sealing. An internal seating shoulder appears at 271 . Downwardly tapered bowl surface is shown at 272 .
FIGS. 57-61 are like 52 - 56 and show a retrievable lower bowl assembly, at 280 , and which also is generally cylindrical. A modified mandrel 20 ′ is received in the bowl assembly and seats at annular shoulder 282 . Mandrel 20 ′ connects to and is part of the hanger assembly, as described. The bowl assembly is typically welded to well conductor pipe. Other attachment means can be used.
Accordingly, the invention provides a retrievable landing system capable of landing casing string weight before or during cement jobs. It enables removal of casing string weight off the landing system which then can be easily removed and re-used
FIG. 62 shows a double hung casing installation, including first means at dual vertical levels or locations 150 and 151 at a well head 152 , for supporting larger diameter hung casing 153 at lower location 150 , and for supporting smaller diameter hung casing 154 at upper location 151 . Structure 157 supported on collar 153 a supports 151 .
Each or both of the first means at the locations 150 and 151 may take the form of the devices shown in FIGS. 1-8 , or FIGS. 31-37 or FIGS. 38-43 , or FIGS. 45-51 . Removable surrounding spools are indicated at 160 - 162 .
Second means for controlling releasing energy stored in the double hung casing, or in each of such casings, in response to controlled reduction in casing support, is provided, for example in the adjustments described above in connection with operation of elements in said Figures.
FIGS. 62 and 63 also show an annular supporting mandrel 170 extending about the casings, and bodily relatively movable or slidable on and lengthwise of the casing, below the double or single hung casing location. As seen in FIGS. 62 and 63 , the slidable mandrel carries and is sealed by O-rings 172 , as at 172 a with the bore 173 of structure 174 , and by O-ring 175 as at 175 a with the outer surface 176 of casing 153 . That ring is pressurized or deformed for sealing. A landing shoulder for the mandrel bevel is provided at 177 .
Accordingly, an additional object includes provision of:
a) a first means providing a double hung casing installation, at a well head, and characterized by energy storage in supported casing, b) And second means for controllably releasing energy storage in the double hung casing in response to controlled reduction in casing support, whereby associated equipment maybe retrieved at the well head, saving time and expense.
Another object includes provision of adjustable support structure extending under casing head structure or structures, and controllably bodily movable out from under the casing head structure or structures after cementing of casing lower extent or extents in the well, and after energy release, as referred to. | The method of installing a plurality of casing sections in a well, that includes providing a hanger supporting the casing sections to extend longitudinally in the well, landing the hanger on structure in the well, whereby weight of the casing sections longitudinally compresses the hanger, cementing the casing sections in position in the well, below the hanger, adjusting the hanger to provide for controllable longitudinal shortening of hanger length, thereby removing exertion of casing weight on the hanger, and removing at least part of the hanger away from the well head. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to processes for forming barrier layers on metal surfaces. It finds particular application in conjunction with forming barrier layers on titanium and aluminum containing substrates, particularly titanium aluminides, which resist oxidation, resist corrosion, resist wear and abrasion, and resist corrosive media.
Titanium aluminide is currently being investigated to replace super alloys for use in aircraft turbine engines and aircraft structures. Titanium aluminide is about half the density of superalloys of comparable strength, so a large reduction in aircraft weight is possible. The titanium aluminide alone is quite brittle, but workers have been able to add other elements to reduce this brittleness. A remaining development problem is that the oxidation resistance of these titanium aluminide compounds is lower than desired at elevated temperature. Therefore, a key factor in increasing the maximum use temperature is the enhancement of oxidation resistance while maintaining creep and strength performance.
Previous attempts to develop a protective coating have resulted in coatings which are unstable or tend to peel off. If a titanium aluminide substrate is oxidized in air or oxygen at high temperature, as is conventionally done, Al 2 O 3 and TiO 2 are formed. These two oxides have different structures and are immiscible in each other. As such, the mixed oxide is porous and weakly bonded to the substrate. Therefore, they are subject to spallation from the substrate. As such, the oxides are not an effective oxygen barrier. That is, they do not prevent the diffusion of oxygen into the substrate and the reaction of oxygen with aluminum, titanium, and other elements below the surface.
The present invention relates to a new and improved technique for forming strongly-bonded surface barriers for titanium aluminide substrates, which overcomes the above-referenced problem, and to the structures produced by such a technique.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, a process for the formation of a specific reactive element bilayer barrier on a titanium aluminide substrate is described. The bilayer barrier comprises an oxide coating formed from the reaction of specific reactive elements within the substrate with oxygen from water vapor in the presence of hydrogen at high temperatures and low oxygen concentrations. This coating is formed by placing at least a surface and contiguous regions of a titanium aluminide material in a gaseous atmosphere with a small concentration of water vapor at a high temperature. That temperature and water vapor concentration are then maintained throughout the oxide formation. The specific reactive elements at the substrate surface are reacted with oxygen from the gaseous hydrogen/water vapor atmosphere to form the bilayer barrier. The barrier layer is strongly bonded to the surface with an aluminum oxide at a substrate/barrier layer interface and a titanium oxide at a barrier layer/gaseous interface.
In accordance with another aspect of the present invention, the product of the process described above is provided. The product is a bilayer oxide coating on a titanium aluminide substrate. The bilayer oxide coating comprises an aluminum oxide layer on the substrate/barrier layer interface and a titanium oxide layer on the barrier layer/substrate interface.
One advantage of the present invention is that it provides a barrier that is resistant to permeation by oxygen.
Another advantage of the present invention is that it forms a barrier which resists wear.
Yet another advantage of the present invention is that it forms a surface barrier which inhibits erosion.
Still another advantage resides in the strong adhesion of a barrier layer to a titanium aluminide substrate.
Still further advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating preferred embodiments and are not be construed as limiting the invention.
FIG. 1 is a Ti—Al phase diagram, giving a graphic description of the weight percent (atomic percent) of aluminum vs. temperature (° C.) in typical Ti—Al substrates;
FIG. 2 is a drawing illustrating the multilayer characteristics of the oxide coating;
FIG. 3 is an ESCA depth profile demonstrating changes in the concentration of titanium as Ti 2 O 3 and aluminum as α-Al 2 O 3 with depth from the gas/substrate interface; and
FIG. 4 is an X-ray diffraction study showing only the presence of α-Al 2 O 3 and Ti 2 O 3 after processing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present application describes the structure and formation of a reactive barrier on the surface of a titanium aluminide substrate. A higher concentration of the specific reactive elements is brought to the surface, and a highly stable oxide of the specific reactive element is formed on the surface of the titanium aluminide substrate. The preferred specific reactive elements present in the immediate invention include aluminum, titanium, and mixtures thereof.
In one embodiment of the present invention, the reactive barrier coating is formed on the surface of the titanium aluminide substrate in a low-oxygen environment. The substrate is heated to an elevated temperature, preferably between about 870 and about 1050° C., in an environment of hydrogen, with a partial pressure of water vapor, preferably about 1 to about 750 ppm, and more preferably between about 1 to about 500 ppm. The temperature is between about 550 and about 1100° C. At this temperature and pressure, all non-specific reactive elements on the surface are reduced. As the less stable surface oxides are reduced by hydrogen, aluminum and titanium atoms are exposed to the fresh oxygen produced by the dissociation of the water vapor and from the dissociation of less stable surface metal oxides which have formed on the substrate. These aluminum and titanium atoms react with the oxygen to produce strong stable aluminum and titanium oxides. These specific reactive element oxides are too stable to be reduced by the hydrogen/water vapor atmosphere.
The preferred process heats the titanium aluminide specimens in a hydrogen atmosphere that contains between about 1 and about 500 ppm of water vapor. Some substrates may take up hydrogen at lower temperatures. Therefore, in those cases, after processing the substrates in the temperature range of about 870 and 1050° C., and upon cooling the furnace down to about 815° C., the hydrogen atmosphere is evacuated from the furnace and the cool down process is continued in a vacuum that contains less than 1 ppm of water vapor. Alternatively, the furnace is backfilled with an inert gas that contains less than 1 ppm of water vapor as the furnace is cooled to room temperature.
In one embodiment of the present invention, the substrate upon which the reactive barrier is formed is a titanium aluminide substrate. The phase diagram of titanium aluminides is shown in FIG. 1 . As can be seen, titanium aluminide substrates have attractive elevated-temperature properties and low density typical of intermetallic compounds. These attributes make titanium aluminide materials very interesting for both engine and airframe applications. These advanced materials are key to technological advancements, and enhanced structural materials are particularly vital to advanced aerospace systems.
Intermetallic compounds, such as titanium aluminide, are defined as having an ordered alloy phase between two metallic elements. An alloy phase is ordered if two or more sublattices are required to describe its atomic structure. The ordered structure of intermetallic compounds exhibits attractive elevated-temperature properties, i.e. strength, stiffness, etc., because of the long-range ordered super-lattice that reduces dislocation mobility and diffusion properties at elevated temperature. The reduced dislocation motion also results in fracture toughness at extremely low ambient temperature.
The immediate process of forming protective oxide coatings on titanium aluminides is effective for all aluminide compounds. This includes the phases β-Ti, Ti 3 Al, γ-TiAl, and TiAl 3 . Because of their low density, the ordered intermetallic titanium aluminides, especially γ-titanium aluminide (TiAl) and α-2-titanium aluminide (Ti 3 Al), are particularly attractive candidates for applications in advanced aerospace engine and airframe components, in both monolithic and composite concepts. A comparison of the characteristics of monolithic titanium aluminides with other aluminides and superalloys is shown in Table 1.
TABLE 1
Melting Points and Densities for Aluminides
Melting Point
Density
Aluminide
(° C.)
(gm cm −3)
Ti 3 Al
1600
4.2
TiAl
1460
3.9
Fe 3 Al
1540
6.7
FeAl
1330
5.6
Ni 3 Al
1390
7.5
NiAl
1640
5.9
Superalloys
1325-1400
9
(typical)
In a preferred embodiment, the titanium aluminide substrate is γ-TiAl, that has been modified by the addition of other elements to improve the mechanical properties of the aluminide substrate. The modified γ-TiAl, which has a density of 3.9 g/cm 3 , less than half the density of typical superalloys is also advantageous. Furthermore, the modified γ-TiAl has a melting point of about 1460° C., a temperature well above the process temperature required to form the protective oxide coatings of the present invention.
Also preferred are titanium aluminide ternary alloys consisting of Ti—Al—X, where X can be elements such as Cr, Nb, Mn, Mo, W, and V. Some examples of these titanium aluminide ternary alloys are Ti-49Al-2W (atomic %), Ti-44Al-2Mo, and Ti-47Al-29V. Also included in this system are titanium aluminide quaternary alloys consisting of Ti—Al—Nb—Y where Y equals Cr or Mn. In general, the processes for forming oxide barrier layers on titanium and aluminum containing substrates relates to all titanium aluminide ternary and quaternary and higher level alloys that contain elements that have been added to produce certain desirable mechanical improvements to the substrate.
Alternatively, the oxide coatings may be formed on other titanium and aluminum containing substrates. Included is the titanium-aluminum system consisting of the titanium-aluminum alloy disordered alpha phase (α-TiAl) and beta phase (β-TiAl). Superalloys, and other alloys, metals, and materials that contain about 2% or more of aluminum and about 2% or more of titanium are also suitable as substrates upon which to form the protective oxides formed by the present invention.
With reference to FIG. 2, a reactive barrier 2 is formed which is a specific reactive element oxide. A titanium aluminide substrate 4 is modified such that the surface of the substrate forms a specific reactive element oxide film that resists corrosion, permeation by hydrogen isotopes, and serves other useful functions. This oxide protective coating 2 is formed because the intermediate titanium oxide, Ti 2 O 3 , not TiO 2 , is formed with the α-Al 2 O 3 . In the low-pressure, high temperature oxygen region provided by the process used, there exists a high solid solubility between both α-Al 2 O 3 and Ti 2 O 3 phases. The two oxide phases have similar lattice constants and the same crystalline structure.
The equilibrium pressure for the formation of α-Al 2 O 3 is below the equilibrium pressure for the formation of Ti 2 O 3 so that an α-Al 2 O 3 layer 6 , the more stable oxide, forms directly on the substrate 4 in preference to a Ti 2 O 3 enriched layer 8 . In this atmosphere and at process temperature, both aluminum and titanium atoms diffuse from the bulk substrate to the substrate surface, react with the oxygen present there, and form their respective oxides. However, α-Al 2 O 3 is the most stable oxide and bonds strongly to the substrate 4 . The titanium oxide on the substrate surface is reduced to titanium by the more reactive aluminum metal present at the surface. As the α-Al 2 O 3 layer 6 grows thicker on the substrate 4 surface, the titanium atoms, reduced from the titanium oxide by the aluminum, diffuse outward toward the oxide/gas interface where they form the oxide, Ti 2 O 3 layer 8 . A distinct separation between the α-Al 2 O 3 and Ti 2 O 3 phases occurs. α-Al 2 O 3 concentrates at an oxide/substrate interface 10 and Ti 2 O 3 concentrates at an oxide/gas interface 12 . The Ti 2 O 3 serves to provide a graded interface to reduce the stress caused by any tensile force applied to try and pull the oxide away from the substrate.
When the newly formed oxide coating is then put in air at high temperature and atmospheric pressure as it typically is in an application, a thin coating of TiO 2 is formed on the previous gas/oxide interface 12 . Since the prior surface coating is mostly Ti 2 O 3 , an intermediate titanium oxide, a thin surface layer of Ti 2 O 3 converts to the layer of fully oxidized TiO 2 in air. The amount of TiO 2 is insignificant in relation to the amount of Ti 2 O 3 formed. ESCA analysis shows the TiO 2 coating is actually very thin, on the order of a few nanometers. The TiO 2 coating exists only at the surface of the oxide coating, with a relatively thick graded layer of Ti 2 O 3 existing between the TiO 2 layer 14 and the α-Al 2 O 3 /substrate interface 10 .
The separation of α-Al 2 O 3 and Ti 2 O 3 phases and formation of the α-Al 2 O 3 /substrate interface are extremely important discoveries, and can be seen in FIGS. 3 and 4. FIG. 3 is an ESCA depth profile of the immediate oxide coating. As can be seen, the concentration of Ti (as Ti 2 O 3 ) is greatest at shallower depths, and the concentration of Al (as α-Al 2 O 3 ) is greatest closer to the substrate surface. FIG. 4 is an X-ray diffraction study showing the presence of α-Al 2 O 3 and Ti 2 O 3 on the substrate surface after processing. This separation shows that the present method forms a strongly-bonded α-Al 2 O 3 oxide directly to a titanium-aluminide substrate. The α-Al 2 O 3 prevents oxygen from reaching the substrate. Later, when exposed to an air or oxygen atmosphere at a selected higher temperature, the intermediate oxide, Ti 2 O 3 , concentrated at the oxide/gas interface, converts to TiO 2 , but only in small quantities, resulting in a very thin film at the surface. Other elements present in the substrate unable to oxidize in the low-oxygen atmosphere, diffuse into the Ti 2 O 3 region, but remain non-oxidized. The result is a mixed α-Al 2 O 3 , Ti 2 O 3 , and non-oxidized element gradient between the gas/oxide interface 12 and the α-Al 2 O 3 oxide barrier 6 on the substrate 4 . Such a gradient spreads the load of any applied tensile force over many atom layers making up the thickness of the mixed oxide/non-oxidized element region so that the oxide coating is strongly bonded to the substrate. The α-Al 2 O 3 , being the oxide that bonds most strongly to the surface of the substrate, is therefore the actual barrier that prevents oxygen diffusion into the substrate. The relatively thick layer of Ti 2 O 3 between the α-Al 2 O 3 and the TiO 2 layers prevents any contact between α-Al 2 O 3 and TiO 2 , which could cause brittleness, peeling, and spallation.
At least about 2 weight percent of aluminum must be present in the substrate to form the α-Al 2 O 3 /substrate oxygen barrier coating with the preferred process. If this limitation is met, the whole range of variation of aluminum with titanium can produce valid protective oxide coatings. The substrates containing the higher percentages of titanium are preferred for their ability to function at higher temperatures.
In one aspect of the present invention, the thickness of the oxide coating is important in determining the strength of the coating. X-ray diffraction studies and electron spectroscopy for chemical analysis data have shown that the strength of the oxide coating varies with the thickness of the oxide coating. If the coating is too thin, there is not enough protection against oxidation. If the coating is too thick, it becomes somewhat cumbersome and loses adhesion properties. The optimum thickness of the oxide coating, where both protection from oxidation and strong adhesion properties remain intact, is between about 500 and about 1500 nm. Stud pull test show that the present coating can survive an applied tensile stress greater than about 69,000 kPa. These tests were carried out via the use of a Sebastion V unit to try to pull the oxide from the substrate in a pull test in which a tensile pull rod is bonded to the oxide surface by epoxy.
In another aspect of the present invention, a sulfur scavenger is used prior to the formation of the coating. Free sulfur in a bulk substrate diffuses to the surface and condenses in voids or cavities, reducing the bond strength of any oxide present. One of the benefits of the present technique is the very strong bonds formed between α-Al 2 O 3 and the titanium aluminide substrate. These bonds have a strength in excess of 69,000 kPa. Therefore, free sulfur is removed from the surface of the substrate. In the preferred process, a flowing hydrogen gas in a preliminary processing step, at atmospheric pressure, between about 550 and 1100° C., and containing about 1 to about 750 ppm water, preferably containing about 1 to about 500 ppm water vapor, reacts with any sulfur that has condensed in voids or cavities at the surface of a substrate. Another hydrogen producing atmosphere is an inert gas such as helium containing preferably less than about 750 ppm of water vapor which produces hydrogen that also reacts with any sulfur in a similar manner. Still another hydrogen producing atmosphere consists only of water vapor, over a partial pressure range of from about 1×10 −6 to about 1×10 −2 kPa, which produces hydrogen that also reacts with any sulfur in a similar manner. The interaction of water vapor with aluminum produces oxygen and hydrogen. The oxygen reacts with aluminum to form α-Al 2 O 3 and the hydrogen is then available to react with sulfur to form hydrogen sulfide—a gas that is removed with the flowing hydrogen.
In another embodiment of the present invention, a repair method for damaged oxide coatings is provided. Damage to the above-mentioned protective oxide coatings in limited regions can be repaired. For example, removal of a small area of oxide may occur by the impact of a high-velocity particle. Or, two previously processed parts may be welded or brazed together, perhaps by laser welding. The resulting weld lacks a proper protective oxide unless the barrier layer formation process is repeated after the weld was completed. Small region repairs are accomplished by heating the locally damaged surface area in the appropriate environment. Such local heating is preferably accomplished by laser-heating procedures.
A scanning mechanism causes a pulsed laser with variable repetitive pulsing rate to sweep in both the X and Y directions over a selected area. The scanning rates of both the X and Y directions are adjusted to provide uniform heating of the damaged or newly welded area, and also to provide a gradient in temperature between the damaged area and the much lower temperature surrounding the oxide protected area. Any laser which operates between ultraviolet and infrared radiation is contemplated. The laser intensity is preferably less than 10 8 J/sec 2 for the ultraviolet wavelengths, and less than 10 11 J/sec 2 for the infrared light. For laser wavelengths between the UV radiation and infrared radiation, the limiting intensity varies approximately linearly with wavelength. Above the limiting laser intensities given, ablation of material may occur. Only heating is desired, so laser intensities below these limits may perform best.
Importantly, the area to be repaired is encompassed by the above-described environment. Particularly, the environment is hydrogen gas at atmospheric pressure that contains approximately 1 to about 500 ppm of water vapor. Another alternate atmosphere is an inert gas such as helium at atmospheric pressure that contains approximately 1 to about 500 ppm of water vapor. Still another alternate atmosphere consists only of water vapor, over a partial pressure range of from 1×10 −6 to 1×10 −2 kpa.
The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | A titanium aluminide substrate ( 4 ) is vulnerable to air oxidation, limiting the use of this substrate in a variety of industrial applications, including the aircraft and aerospace industries. A bilayer reactive barrier ( 2 ) is formed on a titanium aluminide substrate. The barrier layer includes an α-Al 2 O 3 layer ( 6 ) from the reaction of oxygen from the disassociation of water with alumina in a gaseous and water vapor atmosphere at high temperatures and low oxygen concentration. During the process, titanium migrates through the α-Al 2 O 3 to a gas/barrier layer surface ( 14 ) and is oxidized to form a Ti 2 O 3 layer ( 8 ). A surface of the Ti 2 O 3 layer is subsequently oxidized to form a TiO 2 layer ( 12 ). In this manner, a triple layer barrier is formed in which the immersible TiO 2 and α-Al 2 O 3 are separated by Ti 2 O 3 . The three layers are bonded to each with a bond strength greater than 4500 kPa. | 8 |
COPYRIGHT NOTICE
[0001] Portions of this disclosure contain material in which copyright is claimed by the applicant. The applicant has no objection to the copying of this material in the course of making copies of the application file or any patents that may issue on the application, but all other rights whatsoever in the copyrighted material are reserved.
BACKGROUND
[0002] Content comes in a wide range of forms including: (a) music; (b) news of all kinds including world, national and local events, sports, weather and traffic; (c) podcasts or other broadcasts covering different interests; (d) movies; and (e) any other type of content broadcast over airwaves, satellite, cable, the internet or other connectable sources can be offered to a user through a media player and/or downloaded from links on a website for users to access the programming. Users interested in many different sources of content are faced with having to use a variety of players or links to play content from multiple sources and/or being distributed in different forms and formats. Since these sources are independent, there's no common means to determine when particular content of interest to a particular user is updated. For example, geographically relevant content such as traffic or weather is important to travelers in a particular location. For a traveler planning daily activities and looking for the most current, up-to-date information while they are in a city such as New York City, they must conduct a renewed search for the information at each point in time when it is needed.
[0003] The present invention solves these issues by aggregating content from any number of sites or broadcasters by letting users set their favorite content to play over the media player automatically when it's updated. This is done by activating the an AutoPlay function which automatically checks favorite content for updates. New, unheard content is inserted as the next item to play in the user's iNetRadio playlist and may include any mix of different types of content. AutoPlay eliminates the need for users to keep checking for new content. This allows everything from hourly news updates to weekly podcasts to music selections to play with no manual interaction and without any one content selection interfering with another content selection. Instead, the content is queued sequentially so that all content can be heard in order without one type prevailing over another.
[0004] The present invention includes AutoTraffic and AutoWeather features. These features provide travelers who desire local traffic and weather reports with the information they are seeking on the most up-to-date basis, without the distraction of visual traffic maps or the need to search for a local source of information and then wait for the information to be reported. AutoTraffic and AutoWeather functions are activated on the media player by the user. Using geolocation data to find the closest realtime road by road traffic reports (supplied by partner GeoTraffic) or weather reports, this user-specified content is played automatically as updates are provided by content providers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] For a better understanding of the present invention, and to show more clearly how it functions, reference will now be made, by way of example, to the accompanying drawings. The drawings show embodiments of the present invention in which:
[0006] FIG. 1 is a network with one or more servers delivering content to a group of different types of devices;
[0007] FIG. 2 shows a screenshot of an internet media player;
[0008] FIG. 3 shows a screenshot of an internet media player that is in the process of playing NPR news content;
[0009] FIG. 4 shows a screenshot of an internet media player that is in the process of playing an AccuWeather podcast;
[0010] FIG. 5 shows a screenshot of an internet media player that is in the process of playing an ESPN Hockey Today podcast;
[0011] FIG. 6 shows a screenshot of an internet media player that is in the process of playing a song “I Prevail” by the band Blank Space;
[0012] FIG. 7 shows a screenshot of an internet media player that provides a user with the selected city for nearby weather report;
[0013] FIG. 8 shows a screenshot of an internet media player with a listing of Auto/Start-Up Play Items;
[0014] FIG. 9 shows a screenshot of an internet media player that provides a user with the selected content in the sports category;
[0015] FIG. 10 shows a screenshot of an internet media player that provides a user with the selected content in the news category;
[0016] FIG. 11 shows a screenshot of an internet media player that provides a user with the selected content in the music category;
[0017] FIG. 12 is a flowchart of the process for selecting AutoTraffic and AutoWeather content to be played on the media player;
[0018] FIG. 13 is an example of an XML file for AccuWeather in the New York area; and
[0019] FIG. 14 is an example of an XML file for the I-95 GeoTraffic report in Philadelphia.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The present invention will now be described more fully with reference to the accompanying drawings. It should be understood that the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Throughout FIGS. 1-14 , like elements of the invention are referred to by the same reference numerals for consistency purposes.
[0021] FIG. 1 is a system 100 on which a media player residing on one or more devices receives content from one or more content servers 105 . Content servers 105 deliver content over network 110 such as the internet that can be widely distributed to any number of devices also connected to network 110 . The devices may be in various different forms including but not limited to a smartphone 120 a , a tablet computer 120 b , a desktop computer 120 c , a laptop computer 120 d or a gaming device 120 e . Each device 120 a - e is connected to network 110 through a port 125 a - e , respectively. Content servers 105 deliver content of different types including (a) music; (b) news of all kinds including world, national and local events, sports, weather and traffic; (c) podcasts or other broadcasts of different interests; (d) movies; and (e) any other type of content broadcast over airwaves, satellite, cable, the internet or other connectable sources can be offered to a user through a media player and/or download links on a website for users to access the programming.
[0022] It should be understood that the media player may be provided on each device 120 a - e in a number of different forms. For example, a media player 200 of the type shown in the screenshot of FIG. 2 is one that is linked through a browser such as Firefox, Explorer, Safari or any other standard internet browser on which websites can be viewed. However, media player may also be downloaded to reside locally on a mobile device such as smartphone 120 a in the form of a software application or “app.” As can be seen in the screenshot of FIG. 2 , internet media player 200 includes a variety of buttons or input selectors, including a “listing button” 205 , an information button 210 , a pause button 215 and a play button 220 . Other buttons on the player include a music selector 225 , a news selector 230 , a sports selector 235 , a talk selector 240 , a traffic & weather selector 245 and a more selector 250 . A station ID field 255 allows a user to see more information about the current station and a volume control 260 allows a user to adjust the volume. Any of these selectors may be activated, for example, using a keyboard, mouse or trackpad on desktop 120 c or laptop 120 d , or alternatively using a touchscreen on smartphone 120 a or tablet 120 b . Other types of inputs may also be used to control media player such as a stylus for use with a touchscreen or multi-function buttons on a handheld game player for use in conjunction with gaming device 125 e.
[0023] FIGS. 3-11 show media player 200 in different operational modes. For example, FIG. 3 shows media player 200 carrying a NPR hourly news summary segment. As can be seen in FIG. 3 , station ID field 255 displays the NPR hourly news summary identification block. At the same time, a data field 265 carries current scrolling information about the segment that is playing including the station ID, date and time.
[0024] FIG. 4 shows media player 200 carrying a weather forecast. As can be seen in FIG. 4 , station ID field 255 displays an AccuWeather.com podcast identification. At the same time, data field 265 carries current scrolling information about the segment that is playing including the station ID, date and time. History field 270 lists the past segments that have played. The history field is activated by clicking on listing button 205 . The history toggles back and forth between the history listing and the iNetRadio broadcast category with each click of listing button 205 . If so desired, a user can click on any of the segments listed in the history listing to repeat them.
[0025] FIG. 5 shows media player 200 carrying a sports podcast. As can be seen in FIG. 5 , station ID field 255 displays Hockey Today ESPN podcast identification. At the same time, data field 265 carries current scrolling information about the segment that is playing including the station ID, date and time.
[0026] FIG. 6 shows media player 200 playing music. As can be seen in FIG. 6 , station ID field 255 shows the name of the song “I Prevail” by the band “Blank Space.” At the same time, data field 265 carries current scrolling information about the segment that is playing including the station ID, date and time. History field 270 lists the past segments that have played.
[0027] FIG. 7 shows media player 200 after the “traffic & weather” selector 245 has been clicked. As can be seen in FIG. 7 , separate lists are displayed for nearby traffic reports 705 (none within 10 miles), nearby weather reports 710 (New York City, N.Y.), and other recently played reports 715 (New York City, N.Y.). A user can select or unselect an “Auto-Traffic” button 720 and/or an “Auto-Weather” button 725 . When either or both of these buttons are selected, a check mark appears next to them as shown in FIG. 7 . Selecting Auto-Traffic means that anytime there is an updated traffic report within the local area (default of 10 mile radius), the traffic report will be loaded in media player 200 and played next in the queue. Selecting Auto-Weather will likewise play a local weather report when it becomes available. It should be understood that a 10 mile radius is set as the default in media player 200 as shown, but the definition of “local” to cover a larger or smaller area can be set either by the user or the developer of media player 200 . Selecting an “Auto-play & Start-up Play” button 730 takes the user to a new media player screen shown in FIG. 8 that provides a list of auto-play items that will be automatically queued by media player 200 when they become available as requested by the user. When the user is on the screen of FIG. 7 , he may go to the previous screen by clicking the “back” button 735 .
[0028] FIG. 9 shows media player 200 displaying a list of sports items selected by a user to be included in the user's playlist. As can be seen in FIG. 9 , ESPN's Hockey Today 815 is the only item in the playlist. Additional sports podcasts may be added by clicking on an “Add New” header button 905 . Upon doing so, a user is presented with a text box to enter a URL for the new podcast to be included in the playlist. A user may also click on header button labeled “Categories” or 910 or “All” 915 to make other selections to be added to the playlist. The user may go back to the Start-Up Play and Auto Play by clicking on Auto Play & Start-up Play button 730 . To return to a screen showing the media player, the user clicks on “back” button 735 .
[0029] FIG. 10 shows media player 200 displaying a list of news items selected by a user to be included in the user's playlist. As can be seen in FIG. 10 , NPR's Hockey Hourly News Summary 815 is the only item in the playlist. Additional news items may be added by clicking on an “Add New” header button 1005 . Upon doing so, a user is presented with a text box to enter a URL for the new podcast to be included in the playlist. A user may also click on header button labeled “Categories” or 1010 or “All” 1015 to make other selections to be added the playlist. The user may go back to the Start-Up Play and Auto Play by clicking on Auto Play & Start-up Play button 730 . To return to a screen showing the media player, the user clicks on “back” button 735 .
[0030] FIG. 11 shows media player 200 displaying a list of music items selected by a user to be included in the user's playlist. As can be seen in FIG. 11 , the list includes “Top Rock” 1105 , “Top Hits” 1110 and “Caroline” 1115 . Additional music items may be added by clicking on an “Add New” header button 1120 . Upon doing so, a user is presented with a text box to enter a URL for the new podcast to be included in the playlist. A user may also click on header button labeled “Categories,” 1125 , “All” 1130 or “Search” 1135 to make other selections to be added to the playlist. The user may go back to the Start-Up Play and Auto Play by clicking on Auto Play & Start-up Play button 730 . To return to a screen showing the media player, the user clicks on “back” button 735 .
[0031] FIG. 12 is a flowchart 1200 of the process for selecting AutoTraffic and AutoWeather content to be played on the media player. Initially, the user opens media player 200 at step 1205 . Once media player 200 is open, the player clicks traffic & weather button 245 to access the Traffic & Weather page (See FIG. 7 ). The server on which iNetRadio is operating then queries the iNetRadio media player running on the user's device to determine the particular location of the device at step 1215 . It is then determined whether the user location is within an area of desired reports for traffic and weather at step 1220 . If not, there is a 5 minute pause at step 1225 before the iNetRadio player is queried again after returning to step 1215 . In this way, there will be an endless wait period until the user enters a location where reports are available. If the user is within an area of desired reports at step 1220 , then the server queries report the publication dates for updated content at step 1230 and it is determined whether any updated reports are available for the user's location at step 1235 . If not, there is a 5 minute pause at step 1225 again before the iNetRadio player is queried again after returning to step 1215 . In this way, there will be an endless wait period until the user enters a location where reports are available. If there are updated reports available for the user's location, the report is written into the playlist as the next item to play at step 1240 .
[0032] A feature of the invention is that any item added to the sequential playlist is selected by the user. The selection process for an item, particularly for an item that is geographically based such as content related to weather or traffic is prioritized by the user in the selection process. So, for example, the user may set the player to play an updated traffic or weather report for a particular location immediately upon receipt and interrupting any content that is currently being played. Or, the user may set the player to play an updated traffic or weather report only after completing the content item that is currently playing. In that case, if a song or podcast is playing, the weather report or traffic report would be played after the current item reaches its endpoint. Alternatively, it is possible to inform the user that a new update is available by displaying a notice on the media player that an update is available. That way, the user can decide immediately whether to continue listening to the current selection or stop the current selection to get the update. The notice may be in the form of a textual message on the player, or it may be in the form of a highlighted area on the player, or it can be an alarm sound such as a ping alerting the user to the update.
[0033] It will be understood that the type of networks 110 over which content is delivered and other functionality is handled may be one of several different types of networks. These include a Local Area Network (LAN), Wide Area Network (WAN), an intranet, the internet or other classes of networks. Any type of network technology could be used without departing from the principles of the invention. This would include communication via any protocol on any of the layers of the OSI model (ISO/IEC 7498-1) with or without encryption (e.g. SSL encryption, VPN, etc).
[0034] FIG. 13 is an example of an XML file for AccuWeather in the New York area. The <pubDate> tag contains a timestamp provided by the content provider (Thu, 10 Sep. 2015 12:55:44 GMT) which is compared to the database record for this content source from the last detected update. If the <pubDate> data indicates that the content has been updated, the AutoPlay function edits the user's playlist and schedules the updated content to play as the next item.
EXAMPLE
[0035] A user listens to the “iNetRadio 80s Hits” channel all day at work and has BBC World News and AccuWeather NYC set to AutoPlay. Launching the iNetRadio player generates a music playlist that will play the selected music channel until the AutoPlay function detects that either the news or weather content has updated. The updated content is then scheduled into the playlist as the next item and will play after the current song (or other content) has finished.
[0036] The AutoPlay function provides iNetRadio users with a completely automatic entertainment and information system using sources that can be combined in any desired way.
[0037] FIG. 14 is an example of an XML file for the I-95 GeoTraffic report in Philadelphia. In this example, the <pubDate> tag contains a purely numeric string that is used for comparison to detect updated content. If a user has this set to AutoPlay (see FIG. 7 where both Auto-Traffic and Auto-Weather are checked), the report would be inserted into the user's playlist whenever it is updated.
[0038] If a user has AutoTraffic activated, the system additionally uses the user's location (latitude and longitude) derived from geolocation services to choose the closest reports (within 10 miles). The relevant location for each report is determined by GeoTraffic, the creator of the reports. The AutoPlay function then checks for updated content and inserts it as the next item to play.
[0039] AutoWeather works similarly to AutoTraffic by locating the closest forecast location to the user, although the range (radius) is typically significantly greater.
[0040] The screenshot of FIG. 7 shows AutoTraffic selected and NYC area weather selected to AutoPlay. If traveling between cities, the user would hear traffic reports dynamically follow their location but the weather source would remain for NYC.
[0041] Any variation and derivation from the above description and drawings are included in the scope of the present invention as defined by the claims. | A system and method for playing a sequence of items including certain selected items of content. A media player operating on a computing device plays the content that is received over a network from a content server. The user controls the media player using a user interface, and further controls the content that is desired. An auto-content selector allows the user to select content related to a particular subject matter like weather and traffic that is automatically added to the sequence of items to be played based on detected information about the user such as the user's location. | 7 |
RELATED APPLICATION
This application claims priority from Provisional Patent Application Ser. No. 60/360,642, filed Feb. 28, 2002.
BACKGROUND OF THE INVENTION
This invention relates generally to feedthrough capacitor terminal pin subassemblies and related methods of construction, particularly of the type used in implantable medical devices such as cardiac pacemakers and the like, to decouple and shield undesirable electromagnetic interference (EMI) signals from the device. More specifically, this invention relates to a method of providing a conductive coating on the flanges of human implantable hermetic seals for reliable EMI filter attachment, and a method of electrical connection of the feedthrough capacitor to the feedthrough lead wires at the hermetic gold braze. This invention is particularly designed for use in cardiac pacemakers (bradycardia devices), cardioverter defibrillators (tachycardia), neuro-stimulators, internal drug pumps, cochlear implants and other medical implant applications. This invention is also applicable to a wide range of other EMI filter applications, such as military or space electronic modules, where it is desirable to preclude the entry of EMI into a hermetically sealed housing containing sensitive electronic circuitry.
Feedthrough terminal pin assemblies are generally well known in the art for connecting electrical signals through the housing or case of an electronic instrument. For example, in implantable medical devices such as cardiac pacemakers, defibrillators or the like, the terminal pin assembly comprises one or more conductive terminal pins supported by an insulator structure for feedthrough passage from the exterior to the interior of the medical device. Many different insulator structures and related mounting methods are known in the art for use in medical devices wherein the insulator structure provides a hermetic seal to prevent entry of body fluids into the housing of the medical device. However, the feedthrough terminal pins are typically connected to one or more lead wires which effectively act as an antenna and thus tend to collect stray EMI signals for transmission into the interior of the medical device. In the prior art devices, the hermetic terminal pin subassembly has been combined in various ways with a ceramic feedthrough filter capacitor to decouple interference signals to the housing of the medical device.
In a typical prior art unipolar construction (as described in U.S. Pat. No. 5,333,095), a round/discoidal (or rectangular) ceramic feedthrough filter capacitor is combined with a hermetic terminal pin assembly to suppress and decouple undesired interference or noise transmission along a terminal pin. FIGS. 1-6 illustrate an exemplary prior art feedthrough filter capacitor 100 and its associated hermetic terminal 102 . The feedthrough filter capacitor 100 comprises a unitized dielectric structure or ceramic-based monolith 104 having multiple capacitor-forming conductive electrode plates formed therein. These electrode plates include a plurality of spaced-apart layers of first or “active” electrode plates 106 , and a plurality of spaced-apart layers of second or “ground” electrode plates 108 in stacked relation alternating or interleaved with the layers of “active” electrode plates 106 . The active electrode plates 106 are conductively coupled to a surface metallization layer 110 lining a bore 112 extending axially through the feedthrough filter capacitor 100 . The ground electrode plates 108 include outer perimeter edges which are exposed at the outer periphery of the capacitor 100 where they are electrically connected in parallel by a suitable conductive surface such as a surface metallization layer 114 . The outer edges of the active electrode plates 106 terminate in spaced relation with the outer periphery of the capacitor body, whereby the active electrode plates are electrically isolated by the capacitor body 104 from the conductive layer 114 that is coupled to the ground electrode plates 108 . Similarly, the ground electrode plates 108 have inner edges which terminate in spaced relation with the terminal pin bore 112 , whereby the ground electrode plates are electrically isolated by the capacitor body 104 from a terminal pin 116 and the conductive layer 110 lining the bore 112 . The number of active and ground electrode plates 106 and 108 , together with the dielectric thickness or spacing therebetween, may vary in accordance with the desired capacitance value and voltage rating of the feedthrough filter capacitor 100 .
The feedthrough filter capacitor 100 and terminal pin 116 is assembled to the hermetic terminal 102 as shown in FIGS. 5 and 6 . In the exemplary drawings, the hermetic terminal includes a ferrule 118 which comprises a generally ring-shaped structure formed from a suitable biocompatible conductive material, such as titanium or a titanium alloy, and is shaped to define a central aperture 120 and a ring-shaped, radially outwardly opening channel 122 for facilitated assembly with a test fixture (not shown) for hermetic seal testing, and also for facilitated assembly with the housing (also not shown) on an implantable medical device or the like. An insulating structure 124 is positioned within the central aperture 120 to prevent passage of fluid such as patient body fluids, through the feedthrough filter assembly during normal use implanted within the body of a patient. More specifically, the hermetic seal comprises an electrically insulating or dielectric structure 124 such as a gold-brazed alumina or fused glass type or ceramic-based insulator installed within the ferrule central aperture 120 . The insulating structure 124 is positioned relative to an adjacent axial side of the feedthrough filter capacitor 100 and cooperates therewith to define a short axial gap 126 therebetween. This axial gap 126 forms a portion of a leak detection vent and facilitates leak detection. The insulating structure 124 thus defines an inboard face presented in a direction axially toward the adjacent capacitor body 104 and an opposite outboard face presented in a direction axially away from the capacitor body. The insulating structure 124 desirably forms a fluid-tight seal about the inner diameter surface of the conductive ferrule 118 , and also forms a fluid-tight seal about the terminal pin 116 thereby forming a hermetic seal suitable for human implant. Such fluid impermeable seals are formed by inner and outer braze seals or the like 128 and 130 . The insulating structure 124 thus prevents fluid migration or leakage through the ferrule 118 along any of the structural interfaces between components mounted within the ferrule, while electrically isolating the terminal pin 116 from the ferrule 118 .
The feedthrough filter capacitor 100 is mechanically and conductively attached to the conductive ferrule 118 by means of peripheral material 132 which conductively couple the outer metallization layer 114 to a surface of the ferrule 118 while maintaining an axial gap 126 between a facing surface of the capacitor body 104 , on the one hand, and surfaces of the insulating structure 124 and ferrule 118 , on the other. The axial gap 126 must be small to preclude leakage of EMI. The outside diameter connection between the capacitor 100 and the hermetic terminal ferrule 118 is accomplished typically using a high temperature conductive thermal-setting material such as a conductive polyimide. It will also be noted in FIG. 5 that the peripheral support material 132 is preferably discontinuous to reduce mechanical stress and also allow for passage of helium during hermetic seal testing of the complete assembly. In other words, there are substantial gaps between the supports 132 which allow for the passage of helium during a leak detection test.
In operation, the coaxial capacitor 100 permits passage of relatively low frequency electrical signals along the terminal pin 116 , while shielding and decoupling/attenuating undesired interference signals of typically high frequency to the conductive housing. Feedthrough capacitors of this general type are available in unipolar (one), bipolar (two), tripolar (three), quadpolar (four), pentapolar (five), hexpolar (six) and additional lead configurations. The feedthrough capacitors (in both discoidal and rectangular configurations) of this general type are commonly employed in implantable cardiac pacemakers and defibrillators and the like, wherein the pacemaker housing is constructed from a biocompatible metal, such as titanium alloy which is electrically and mechanically coupled to the hermetic terminal pin assembly which in turn is electrically coupled to the feedthrough filter capacitor. As a result, the filter capacitor and terminal pin assembly prevents entrance of interference signals to the interior of the pacemaker housing, wherein such interference signals could otherwise adversely affect the desired cardiac pacing or defibrillation function.
It is well known in the art that titanium has a tendency to form oxides, particularly at high temperature. Titanium oxide (or trioxide) is typical of the oxides that form on the surfaces of titanium. Titanium oxide is very rugged and very stable and in fact is often used as a pigment in paints due to its long-term stability. It is also an insulator or semiconductor.
In the prior art, the attachment between the capacitor outside diameter metallization 114 and the titanium ferrule 118 is accomplished using a thermalsetting conductive adhesive 132 , such as a conductive polyimide. Ablestick Corporation manufactures such polyimide compounds. If the oxide layer 134 builds up sufficiently in thickness, this can form an insulative surface which can preclude the proper operation of the feedthrough capacitor 100 as an effective electromagnetic interference filter. It is essential that the capacitor ground electrode plates 108 have a very low resistance and low impedance connection at RF frequencies. This is essential so that it can perform as a proper high frequency bypass element (transmission line) which will short out undesirable electromagnetic interference such as that caused by cellular telephones and other emitters. If the oxide layer 134 is very thin, it creates only a few milliohms of extra resistance. However, recent measurements indicate that a thicker oxide layer can create resistance (measured at 10 MHz) ranging from 750 milliohms to over 30 ohms.
In the past, this oxide layer 134 was very difficult to detect with conventional measuring instruments. Agilent Technologies has recently produced a new piece of equipment known as the E4991A Materials Analyzer. This materials analyzer has the capability to measure equivalent series resistance and other properties of capacitors at very high frequency.
Some background in dielectric theory is required to understand the importance of this. FIG. 7 is the schematic representation for an ideal capacitor C, which does not actually exist. In this regard, all capacitors have varying degrees of undesirable resistance and inductance. This is explained in more detail in “A Capacitor's Inductance,” Capacitor and Resistor Technology Symposium (CARTS-Europe), Lisbon, Portugal, Oct. 19-22, 1999, the contents of which are incorporated herein.
FIG. 8 is a simplified equivalent circuit model of the capacitor. For the purposes of these discussions, the IR can be ignored as it is in the millions of ohms and does not significantly contribute to the capacitor equivalent series resistance (ESR). IR also has negligible effect on capacitor high frequency performance. The inductance (ESL) can also be ignored because inductive reactance for monolithic ceramic capacitors is very low at low frequencies. Inductance for a feedthrough capacitor is very low and can be thought of as negligible at high frequencies. Accordingly, the capacitor ESR is the sum of the dielectric loss, the ohmic losses and any losses due to skin effect. However, at low frequency, skin effect is negligible.
Therefore, a good low frequency model for capacitor ESR is as shown in FIG. 9 . At low frequency, the capacitor ESR is simply the sum of the capacitor's ohmic and dielectric losses.
FIG. 10 illustrates a normalized curve which shows the capacitor equivalent series resistance (ESR) on the Y axis versus frequency on the X axis. This curve has been highly compressed into a U shape so that all of the important points can be illustrated on one graph. However, one should imagine FIG. 10 stretched out along its X axis by many times to get the true picture. The important point here is the dielectric loss is also known as the dielectric loss tangent. The dielectric material that is used to build the monolithic ceramic capacitor is in itself capable of producing real loss (resistance) which varies with frequency. The dielectric resistance is very high at low frequency and drops to zero at high frequency. This effect can be thought of as oscillations in the crystal structure that produce heat or changes in electronic or electron spin orbits that also produce heat. No matter which dielectric model one uses, this dielectric loss can be very significant at low frequency. In the EMI filter capacitor that's typically used in cardiac pacemakers and implantable defibrillators, a capacitance value of around 4000 picofarads is typical. Typical values of dielectric loss would be around 4000 ohms at 1 kHz, around 6 to 12 ohms at 1 MHz, and only a few milliohms at 10 MHz. This clearly indicates that as one goes up in frequency the dielectric loss tends to disappear.
Since the 1960s it has been a common practice in the capacitor industry to measure capacitance and dissipation factor at 1 kHz. The dissipation factor is usually defined as a percentage, for example, 2.5% maximum. What this means is that the dielectric loss resistance can be no more than 2.5% of the capacitive reactance at a certain frequency (usually 1 kHz). For example, if the capacitive reactance for a particular capacitor was 80,000 ohms at 1 kHz with a 2% dissipation factor this would equate to 1600 ohms of resistance at 1 kHz. FIG. 10 also illustrates that the dielectric loss essentially goes to zero at high frequency. For typical high dielectric constant monolithic ceramic capacitors, anything above 10-20 MHz will be sufficiently high in frequency so that the dielectric loss is no longer a factor in the capacitor ESR measurement. FIG. 10 also has superimposed on it another curve representing conductor ohmic loss which in a monolithic ceramic feedthrough capacitor is typically on the order of 0.25 ohms to 0.75 ohms. It should be pointed out that values of equivalent series resistance presented herein relate to only one illustrative example. In actual fact, the ESR of the capacitor varies with the capacitance value, the number of electrode plates, and the length and width of the electrode plates. Accordingly, a wide range of “normal” ESR readings can be obtained for many types of capacitors. For one particular capacitor a normal ESR reading might be 0.05 ohms and for another design as much as 10 ohms. The important thing is that the ESR reading and the lot population represent oxide free connections that are very homogenous and the readings are stable across the lot population.
It is also possible to detect those parts in a manufacturing lot population that for one reason or another have an abnormally high resistance reading. This can be done at 1 MHz by very tightly controlling the maximum allowable ESR. This is being done in the presence of relatively high dielectric loss. However, by holding a very tight screening limit it is still possible to detect such out of population part. This measurement is, of course, easier to do at 10 MHz, but also quite practical at 1 MHz.
The conductor ohmic losses come from all of the feedthrough capacitor conductor materials and connections. That would include the lead wire or circuit trace itself, the electrical connection between the lead wire and the capacitor metallization, which might be solder or a thermalsetting conductive adhesive, the interface between the capacitor metallization and the internal electrode plates, the connection from the capacitor ground metallization to a ferrule, and the bulk resistance of the electrode plates themselves. Conductor ohmic loss does not vary with frequency until skin effect comes into play. Skin effect is also shown on FIG. 10 and one can see that the resistance starts to climb at the higher frequencies. For physically small MLC chips and feedthrough capacitors, skin effect does not really play a role until one gets to very high frequencies, for example, above 200 MHz.
FIG. 11 is a more detailed illustration of the dielectric loss shown by itself. At very low frequency the dielectric loss in ohms is quite high and as frequency increases, one can see that dielectric loss tends to go to zero. On this scale, the conductor ohmic losses, which are shown as metal loss, can hardly be detected (these are only a few milliohms in this case).
As previously mentioned, titanium oxide (or niobium or tantalum oxides) can vary in resistance from a few milliohms all the way up to 10 or even 30 ohms. A recently discovered problem is that when one makes measurements at 1 kHz it is impossible to see the effects of these oxides because they are hidden by the dielectric loss tangent, which can be as high as 4000 ohms or more by itself. Trying to find a resistance that has increased from 0.25 ohms for a titanium surface that is free of oxide up to 2 ohms is literally impossible in the presence of 4000 ohms of dielectric loss. The reason for this is that the dielectric loss can vary slightly from part to part (typically plus or minus 20 percent). Therefore, when one is making measurements on a manufacturing lot of ceramic EMI feedthrough capacitors for medical implant applications, the part to part variation at 1 kHz can be as much as 100 ohms due to dielectric loss tangent variation alone. Therefore, it becomes quite impossible to detect the presence of this undesirable oxide layer on the titanium surface. However, the recently introduced Agilent equipment is capable of making dielectric equivalent series resistance measurements at 10 MHz and above. This is a high enough frequency to get rid of the dielectric loss so that one can see the ohmic loss by itself (without being hidden under the dielectric loss).
FIG. 12 is a sweep from the Agilent E4991A RF Impedance-Materials Analyzer. Curve 136 illustrates the capacitor equivalent series resistance vs. frequency. The presence of these oxides can reduce EMI filter performance by as much as 20 dB. Stated another way, this could reduce EMI filtering effectiveness by a ratio of 10 to 1 or more. This is highly undesirable in an implantable medical device given the previous documented clinical interactions between cellular telephones and pacemakers. For example, it has been shown that cellular telephone interference can completely inhibit a pacemaker or cause it to go into asynchronous tracking or other undesirable behavior. This can be very dangerous even life threatening for a pacemaker-dependent patient. Further compounding this concern is the recent introduction throughout the marketplace of cellular telephone amplifiers.
One example of this is in the off shore marine boating environment. Until recently maritime communications were primarily limited to the VHF radio. However, many boaters are now relying on cellular telephones for their communication. Accordingly, a number of companies have introduced cellular telephone amplifiers which boost cellular telephone output from 0.6 watts maximum to 3 watts. In addition, high gain marine antennas are being manufactured which can be anywhere from 4 to 8 feet long. These provide an additional 9 dB of gain in the extreme case. Passengers on these boats are being subjected to much higher field intensities than were previously contemplated by the FDA.
Another area where cellular telephone amplifiers are becoming increasingly popular is for wireless Internet connections for lap top computers. It is now possible to buy small black box devices that plug into the wall and also plug into the cellular telephone. These devices then plug into the lap top computer. This boosts the cellular telephone output to 3 watts and also provides a high gain antenna all of which sit on a desk top right in front of the operator. There are also remote credit card scanning devices that operate under similar principles. In short, the public is increasingly being exposed to higher levels of electromagnetic fields.
Accordingly, there is an urgent and present need for EMI filtered terminals for implantable medical devices that will not only maintain their present performance (by not degrading in the presence of oxides) but also increase in their performance. Co-bonded ferrite slabs are being contemplated in order to further increase filter performance in conjunction with the principles outlined here. This will allow future capacitor connections with very low ESR and very low potential for oxidation at attachment points. In addition, the additional ferrite slab will change it from a single element EMI filter to a double EMI filter (L filter). Accordingly, increased performance at cellular phone frequencies offered thereby providing complete immunity to the aforementioned new signal amplifiers. Returning to FIG. 12 one can see from the resistance curve 136 that at the far left hand side of the sweep ( 1 ) at 1 MHz, the resistance is approximately 6 ohms. This means that there is a significant, but small amount of dielectric loss tangents still present at 1 MHz (the dielectric loss tangent at 1 kHz is 1800 ohms). However, when one goes up to marker ( 2 ), which is at 10 MHz, we're at a point where the dielectric loss tangent has all but disappeared. At this point, we are primarily seeing the true ohmic losses of the device. The device measured in FIG. 12 has no titanium oxide build-up. Accordingly, at marker ( 2 ) we have a very low resistance measurement of 234.795 milliohms (0.234 ohms).
FIG. 13 is the same as the sweep in FIG. 12 except this is taken from a part that has a substantial amount of undesirable titanium oxide build-up. Curve 136 illustrates that at marker ( 2 ) there is 23.2529 ohms of resistance present. FIG. 13 clearly illustrates that there is enough titanium oxide build-up to create 23.2529 ohms of series resistance at 10 MHz (a normal reading is 0.234 ohms for this particular capacitor). This is highly undesirable because it will preclude the proper operation of an EMI filter at this frequency and frequencies above.
FIGS. 14-19 illustrate a prior art rectangular bipolar feedthrough capacitor (planar array) 200 mounted to the hermetic terminal 202 of a cardiac pacemaker in accordance with U.S. Pat. No. 5,333,095. Functionally equivalent parts shown in this embodiment relative to the structure of FIGS. 1-6 will bear the same reference number, increased by 100.
As illustrated in FIGS. 14-19 , in a typical broadband or low pass EMI filter construction, a ceramic feedthrough filter capacitor, 200 is used in a feedthrough assembly to suppress and decouple undesired interference or noise transmission along one or more terminal pins 216 , and may comprise a capacitor having two sets of electrode plates 206 and 208 embedded in spaced relation within an insulative dielectric substrate or base 204 , formed typically as a ceramic monolithic structure. One set of the electrode plates 206 is electrically connected at an inner diameter cylindrical surface of the capacitor structure 200 to the conductive terminal pins 216 utilized to pass the desired electrical signal or signals (see FIG. 16 ). The other or second set of electrode plates 208 is coupled at an outer edge surface of the capacitor 200 to a rectangular ferrule 218 of conductive material (see FIG. 18 ). The number and dielectric thickness spacing of the electrode plate sets varies in accordance with the capacitance value and the voltage rating of the capacitor 200 .
In operation, the coaxial capacitor 200 permits passage of relatively low frequency electrical signals along the terminal pins 216 , while shielding and decoupling/attenuating undesired interference signals of typically high frequency to the conductive housing. Feedthrough capacitors 200 of this general type are available in unipolar (one), bipolar (two), tripolar (three), quadpolar (four), pentapolar (five), hexpolar (6) and additional lead configurations. Feedthrough capacitors 200 (in both discoidal and rectangular configurations) of this general type are commonly employed in implantable cardiac pacemakers and defibrillators and the like, wherein the pacemaker housing is constructed from a biocompatible metal such as titanium alloy, which is electrically and mechanically coupled to the hermetic terminal pin assembly which is in turn electrically coupled to the coaxial feedthrough filter capacitor. As a result, the filter capacitor and terminal pin assembly prevents entrance of interference signals to the interior of the pacemaker housing, wherein such interference signals could otherwise adversely affect the desired cardiac pacing or defibrillation function.
FIG. 15 illustrates an unfiltered hermetic terminal 202 typical of that used in medical implant applications. The ferrule 218 is typically made of titanium or other biocompatible material. An alumina insulator 224 or other insulative material such as glass or the like, is used to electrically isolate the leads 216 from the conductive ferrule while at the same time providing a hermetic seal against body fluids. In the case of an alumina insulator, the lead wires or leads 216 are installed into the insulating material 224 typically by gold brazing. A gold braze is also formed between the alumina 224 and the ferrule 218 . In some applications, this can also be done with sealing glass so that the gold brazes are not required. The reference numbers 228 and 230 , on the one hand, and 228 ′ and 230 ′, on the other (FIG. 19 ), show gold brazes in two alternate locations that are used to form the hermetic seal between the titanium ferrule 218 and the alumina insulator 224 .
FIG. 18 illustrates the capacitor 200 mounted to the hermetic terminal 202 of FIG. 15 . The attachment 232 between the capacitor ground metallization 214 and the titanium ferrule 218 is typically done with a conductive thermalsetting polymer, such as conductive polyimide or the like. It is also required that an electrical/mechanical connection be made between the capacitor inside diameter holes 212 and the four lead wires 216 . This is shown at 244 and can be accomplished with a thermalsetting conductive adhesive, solder, welding, brazing or the like.
FIG. 19 is a cross-sectional view of the capacitor assembly of FIG. 18 , which is typical of prior art capacitors shown in U.S. Pat. No. 5,333,095 and related patents. In FIG. 19 , one can see the undesirable oxide layer 234 . This oxide layer can actually coat all surfaces of the titanium ferrule (for simplicity, it is only shown on FIG. 19 in the area where the conductive polyimide attachment 232 is made to the capacitor ground termination 214 ). The thermalsetting conductive material 232 connects between the capacitor ground metallization 214 and the ferrule 218 . However, if there is an insulative titanium oxide layer 234 as shown, this can preclude the proper operation of the feedthrough capacitor 200 as previously mentioned.
From the foregoing it is seen that titanium housings, casings and ferrules for hermetic seals are commonly used in the medical implant industry. Pacemakers, implantable defibrillators, cochlear implants and the like, all have ferrules or housings made of titanium. All of the aforementioned devices are also subject to electromagnetic interference (EMI) from emitters that are commonly found in the patient environment. These include cell phones, microwave ovens and the like. There are a number of prior art patents which describe EMI feedthrough filters which make the implantable devices immune to the effects of EMI.
The presence of oxides of titanium can preclude the proper performance of monolithic ceramic EMI feedthrough filters. The titanium oxides that form during manufacturing processes or handling form a resistive layer, which shows up at high frequency. High frequency impedance analyzer plots of resistance vs frequency illustrate that this effect is particularly prominent above 10 MHz. There is a significant need, therefore, for a novel method of providing a conductive coating on the ferrules of human implantable hermetic seals for reliable EMI filter attachment. Further, there is a need for a novel method of electrical connection of feedthrough capacitor lead wire inside diameter termination directly to the gold termination or other similarly capable material of hermetic seals and corresponding lead wire(s). The present invention fulfills these needs and provides other related advantages.
SUMMARY OF THE INVENTION
The present invention resides in an EMI feedthrough filter terminal assembly which utilizes oxide resistant biostable conductive pads for reliable electrical attachments. Broadly, the EMI feedthrough filter terminal assembly comprises a feedthrough filter capacitor, a conductive ferrule, a conductive terminal pin, and an insulator that is fixed to the ferrule for conductively isolating the terminal pin from the ferrule.
More particularly, the feedthrough filter capacitor includes first and second sets of electrode plates, a passageway therethrough having a first termination surface conductively coupling the first set of electrode plates, and a second termination surface which exteriorly couples the second set of electrode plates. The conductive ferrule is disposed adjacent to the feedthrough filter capacitor. At least one conductive terminal pin extends through the passageway in conductive relation with the first set of electrode plates. The terminal pin also extends through the ferrule in non-conductive relation.
In illustrated embodiments of the present invention the terminal assembly includes means for hermetically sealing passage of the terminal pin through the ferrule. The ferrule and the insulator comprise a pre-fabricated hermetic terminal pin sub-assembly.
The second termination surface may comprise a plurality of second termination surfaces. In such case, the ferrule includes a corresponding plurality of conductive pads conductively coupled to the plurality of second termination surfaces. Conductive connectors extend between the respective sets of second termination surfaces and conductive pads. The conductive pads typically comprise a noble metal, such as gold bond pads. The conductive connectors are typically taken from the group consisting of conductive polyimide or solder.
The first passageway through the feedthrough filter capacitor may comprise a plurality of first passageways each having a distinct first termination surface which is conductively coupled to a distinct first set of electrode plates. In such case, the at least one conductive terminal pin comprises a terminal pin extending through each of the plurality of first passageways.
A second oxide resistant biostable conductive pad may be conductively attached to the at least one lead wire. Means are then provided for conductively coupling a second noble metal pad to the first termination surface independently of the lead wire. Such structure utilizes such biostable conductive pads for reliable electrical attachments to both the first and second sets of electrode plates.
Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the invention. In such drawings:
FIG. 1 is a top and side perspective view of a typical unipolar ceramic discoidal feedthrough capacitor;
FIG. 2 is an enlarged sectional view taken generally along the line 2 — 2 of FIG. 1 ;
FIG. 3 is a horizontal section taken along the line 3 — 3 of FIG. 2 , illustrating the configuration of the ground electrode plates within the capacitor;
FIG. 4 is a horizontal section taken generally along the line 4 — 4 of FIG. 2 , illustrating the configuration of the active electrode plates within the capacitor;
FIG. 5 is a perspective view of the capacitor of FIGS. 1-4 , mounted to a typical hermetic terminal;
FIG. 6 is an enlarged sectional view taken generally along the line 6 — 6 of FIG. 5 ;
FIG. 7 is a schematic representation of an ideal capacitor;
FIG. 8 is a simplified equivalent circuit model for a real capacitor;
FIG. 9 is a schematic illustrating a low frequency model for capacitor ESR;
FIG. 10 is a graph illustrating normalized curves which show the capacitor equivalent series resistance (ESR) on the y axis, versus frequency on the x axis;
FIG. 11 is a graph illustrating dielectric loss versus frequency;
FIG. 12 is a graph illustrating capacitor equivalent series resistance versus frequency as illustrated in a sweep from an Agilent E4991A materials analyzer;
FIG. 13 is a graph similar to that shown in FIG. 12 , illustrating the resistance in a feedthrough filter capacitor assembly when a substantial amount of titanium oxide is present on the ferrule;
FIG. 14 is a perspective view of a rectangular broadband or low pass EMI filter capacitor;
FIG. 15 is a perspective view of a prior art unfiltered hermetic terminal typical of that used in medical applications;
FIG. 16 is a horizontal section taken generally along the line 16 — 16 of FIG. 14 , illustrating the configuration of active electrode plates within the capacitor;
FIG. 17 is a horizontal section taken generally along the lines 17 — 17 of FIG. 14 , illustrating the configuration of a set of ground electrode plates within the capacitor;
FIG. 18 illustrates the capacitor of FIG. 14 mounted to the hermetic terminal of FIG. 15 ;
FIG. 19 is an enlarged sectional view taken generally along the line 19 — 19 of FIG. 18 ;
FIG. 20 is a hermetic terminal similar to that illustrated in FIG. 15 , but modified in accordance with features of the present invention;
FIG. 21 is a perspective view similar to FIG. 18 , illustrating a rectangular feedthrough capacitor mounted to the hermetic terminal of FIG. 20 ;
FIG. 22 is an enlarged sectional view taken generally along the line 22 — 22 of FIG. 21 ;
FIG. 23 is a perspective view of a surface mount round quadpolar feedthrough capacitor embodying the present invention;
FIG. 24 is an enlarged sectional view taken generally along the line 24 — 24 of FIG. 23 ;
FIG. 25 is a chart illustrating the mechanical properties of thermoplastic polyimide supported tape adhesive;
FIG. 26 is a sectional view similar to FIG. 24 , illustrating a prior art feedthrough filter capacitor terminal typical of that shown in U.S. Pat. No. 4,424,551;
FIG. 27 is a sectional view similar to FIGS. 24 and 26 , illustrating an alternative embodiment of a prior art feedthrough filter capacitor terminal;
FIG. 28 is a sectional view similar to FIGS. 26 and 27 , and further illustrating application of the present invention;
FIG. 29 is an enlarged view of the area indicated by the number 29 in FIG. 28 ;
FIG. 30 is an enlarged view of the area indicated by the number 30 in FIG. 28 ;
FIG. 31 is a perspective view of an internally grounded bipolar rectangular feedthrough capacitor as illustrated and described in U.S. Pat. No. 5,905,627;
FIG. 32 is a perspective view of a hermetic terminal suitable for use with the internally grounded feedthrough capacitor of FIG. 31 ;
FIG. 33 is a sectional view through the capacitor of FIG. 31 , illustrating the active electrode plates;
FIG. 34 is a sectional view similar to FIG. 33 , illustrating the configuration of the ground electrode plates;
FIG. 35 is a perspective view of the internally grounded bipolar feedthrough capacitor of FIG. 31 mounted to the hermetic feedthrough terminal of FIG. 32 ;
FIG. 36 is a cross-sectional view taken generally along the line 36 — 36 of FIG. 35 ;
FIG. 37 is a perspective view of a hybrid capacitor which has the characteristics of a conventional surface-mounted feedthrough capacitor and an internally grounded capacitor;
FIG. 38 is a horizontal section through the capacitor of FIG. 37 , illustrating the configuration of the ground electrode plates therein;
FIG. 39 is a horizontal section similar to FIG. 38 , illustrating the configuration of the active electrode plates therein;
FIG. 40 is a perspective view of an hermetic terminal designed for use in connection with the capacitor illustrated in FIGS. 37-39 , the terminal including a titanium ferrule;
FIG. 41 is a top plan view of the capacitor of FIG. 37 mounted to the hermetic terminal of FIG. 40 ;
FIG. 42 is a sectional view taken generally along line 42 — 42 of FIG. 41 ;
FIG. 43 is a sectional view similar to FIG. 42 , illustrating a hybrid capacitor which has a centered ground pin and which is also grounded at its right and left ends to gold bond pads;
FIG. 44 is an enlarged, perspective and partially exploded view of one of the terminal pins shown in FIG. 43 ;
FIG. 45 is a sectional view similar to FIG. 43 , illustrating an internally grounded hex polar capacitor and related hermetic terminal embodying the present invention;
FIG. 46 is an enlarged perspective view of a terminal pin utilized in the structure of FIG. 45 ;
FIGS. 47A-C are an enlarged fragmented and sectional views of the area indicated by the line 47 in FIG. 45 , illustrating three different embodiments of attachment of the lead wire;
FIG. 48 is a sectional view similar to FIGS. 43 and 45 , illustrating an externally grounded quadpolar device; and
FIG. 49 is an enlarged fragmented view of the area 49 shown on FIG. 48 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Titanium housings, casings and ferrules for hermetic seals are commonly used in the medical implant industry. Pacemakers, implantable defibrillators, cochlear implants and the like, all have ferrules or housings made of titanium or titanium-ceramic composite structures. All of the aforementioned devices are also subject to electromagnetic interference (EMI) from emitters that are commonly found in the patient environment. These include cell phones, microwave ovens and the like. There are a number of prior art patents which describe EMI feedthrough filters which make the implantable devices immune to the effects of EMI.
The inventors have noted that the presence of oxides of titanium can preclude the proper performance of monolithic ceramic EMI feedthrough filters. The titanium oxides that form during manufacturing processes or handling form a resistive layer. High frequency impedance analyzer plots of resistance vs frequency illustrate this effect is particularly prominent above 10 MHz. The novel invention as described herein deposits an oxide resistant conductive coating on the surface of the titanium to provide a resistively stable area to which the ground electrode plates of the feedthrough capacitor can be reliably and consistently attached. Attachments between the capacitor ground electrode plates are typically performed in the prior art by a conductive termination layer which is a part of the feedthrough capacitor, wherein the termination layer connects the ground electrode plates in parallel. The termination material as described in the prior art provides a convenient electrical and solderable connection to the capacitor ground electrode plates. The active electrode plates are similarly terminated at their inside diameter (feedthrough holes).
The primary role of the EMI filter capacitor is to appear as a very low impedance at RF frequencies. The presence of resistance due to a titanium oxide in the capacitor connection undesirably raises its overall impedance. Oxides of titanium are additionally problematic in that they are not stable with time and temperature (they can continue to build-up). These oxides can preclude the proper filtering function of the capacitor. For example, the presence of 23.25 ohm titanium oxide(s) resistance overwhelms the impedance of the feedthrough capacitor, which generally measures less than 600 milliohms at the HF frequency band. This means that the feedthrough capacitor is no longer an effective EMI filter.
The reason that EMI filters are placed at the point of lead ingress in implantable medical devices such as cardiac pacemakers, implantable defibrillators and the like, is to be sure that the implanted electronic device will continue to operate properly in the presence of electromagnetic fields. A notorious example is the microwave oven. It wasn't that many years ago that a number of serious interactions were documented between microwave ovens and cardiac pacemakers and warning signs appeared in stores and other places that were using such devices. The titanium housing that encompasses modern implantable devices largely precludes problems from microwave ovens along with effective EMI filters. Another notable example is the cellular telephone (and other hand held wireless communication devices). Extensive testing by the FDA, by Mount Sinai Medical Center, by Oklahoma University, the Mayo Clinic and other institutions has documented serious interactions between cellular telephones and cardiac pacemakers and implantable defibrillators. In implantable defibrillators, inappropriate therapy delivery has been documented. This means that the defibrillator delivers a painfully high voltage shock where it is not necessary to cardiovert the heart. In this case the implantable defibrillator has confused electromagnetic interference with a chaotic ventricular rhythm. EMI filters that properly decouple these signals provide the degree of patient safety that is required. However, if the filter performance degrades in the presence of the oxides as mentioned, then the patient is clearly at risk. This means that the elimination of these oxides is essential to eliminate a serious public safety concern.
The connection between the capacitor ground termination and the titanium ferrule is typically done using a thermalsetting conductive material such as a conductive polyimide material or the like. The reason for this is that titanium is not solderable. The use of conductive thermalsetting materials to make this connection is well known in the art.
The novel conductive coating of the titanium ferrule of the hermetic seal as described herein is accomplished in one of a variety of ways:
1. Deposition of gold braze material in selected areas of the flange that line up with the capacitor ground electrode terminations. Accordingly, electrical connection between capacitor termination and the gold braze material can still be accomplished as described in the prior art using the conductive polyimide. A novel feature of the invention is that said connection is now achievable with conventional soldering processes. 2. Physical vapor deposition, e.g. sputtering of various materials such as gold or platinum, and various other conductively joinable materials onto the titanium surface. 3. Selected electroplating of gold, platinum, or other materials on the titanium flange for the purposes of facilitating the capacitor ground electrode connection. 4. Plasma arc deposition 5. Ion beam 6. Chemical vapor deposition 7. Laser ablation 8. Or any other deposition method that will achieve the end result described.
It should be apparent to those skilled in the art that the techniques described herein are also applicable to other hermetic seal ferrule materials like niobium, tantalum, and the like. The present invention is also applicable to a variety of other hermetic seal applications as used in oil well logging, aerospace, military and other applications.
A related invention is also shown in the accompanying drawings. This is the unique capability of connecting directly between the lead wire and the gold braze. This is of great advantage for lead materials that form heavy oxide layers, are non-solderable, or both. For biomedical applications, this allows the use of titanium, niobium, tantalum and other lead materials which are much less expensive than the current platinum or platinum-iridium leads.
In the following description, elements of the feedthrough filter capacitor assemblies described herein which are functionally equivalent to one another and to the feedthrough filter capacitor assemblies of FIGS. 1-6 and 14 - 19 described above, will retain common reference numbers, but increased in increments of 100.
FIG. 20 illustrates a hermetic terminal 302 which is similar to the hermetic terminal 202 of FIG. 15 , but which has been modified in accordance with the present invention by extending a gold braze area 346 to create a rectangular pad as shown. The gold braze 346 , which runs around the alumina insulator 324 , is also run into two pockets that are convenient for capacitor mounting.
FIG. 21 shows a quadpolar feedthrough capacitor 300 (which is identical to the capacitor 200 of FIG. 14 ) mounted to the hermetic terminal of FIG. 20 . As one can see in FIG. 21 , the conductive polyimide material 332 now connects between the capacitor metallization 314 and the gold braze area 346 . The gold braze forms a metallurgical bond with the titanium and precludes any possibility of an oxide forming. Gold is a noble metal that does not oxidize and remains very stable even at elevated temperatures. The novel construction methodology illustrated in FIG. 21 guarantees that the capacitor ohmic losses will remain very small at all frequencies.
FIG. 22 is a cross-section of the capacitor shown in FIG. 21 . One can see that the gold braze (or weld) areas 328 and 330 that form the hermetic seal between the alumina insulator 324 and the titanium ferrule 318 are desirably on the feedthrough capacitor side. This makes it easy to manufacture the gold bond pad area 346 for convenient attachment of the conductive thermalsetting material 332 . In other words, by having the gold braze hermetic seals on the same side as the gold bond pad area, these can be co-formed in one manufacturing operation in a gold braze vacuum furnace. Further, a unique thermalsetting material 348 is disposed between the capacitor 300 and the underlying hermetic terminal 302 .
Another feature of the present invention is that in the prior art only conductive thermalsetting materials could be used to electrically connect the capacitor ground metallization 314 to the ferrule 318 . This is because titanium, niobium, tantalum and other biocompatible materials used for human implant ferrules are generally not solderable. With the present invention, it is now possible to replace the thermalsetting conductive adhesive with solder. Solder paste could also be used. This is because solder will properly wet and bond to the gold braze area 346 . Solder reflow operations tend to be more cost efficient (more automatable) as compared to dispensing of thermalsetting conductive adhesives. It should also be noted that the gold bond pad area 346 of FIG. 21 could be achieved using other methods. Gold brazing is one method that has already been described. However, sputter coatings of material surfaces such as gold, platinum or other conductive materials could be done. In addition, the gold bond pad area 346 could be done by electroplating of a suitable material that would form an electrical bond to the titanium and preclude oxide formation or by any other deposition method capable of achieving the desired result.
Accordingly, it will be understood that a novel feature of the present invention is the capability of producing a hermetic seal using noble materials such as gold braze while at the same time forming a gold bond pad or landing area to which to connect the capacitor ground metallization. With specific reference to FIG. 22 , the hermetic seal 330 forms a hermetic braze connection between the ferrule 302 and the alumina insulator 324 . This also, at the same time, forms the gold bond pad 346 for convenient connection of the conductive polyimide 332 . The conductive polyimide forms the electrical connection between the capacitor ground electrode plates through the capacitor metallization 314 which connects directly to the conductive polyimide 332 and to gold bond pad 346 .
There are a number of advantages in having the hermetic connection 330 be co-formed with gold bond pad 346 . First of all there is a very significant manufacturing advantage to having this all done in one operation. A single gold pre-form can be used, which is formed to accommodate the area as shown. In addition, this can all be done in one batch of product put into the vacuum gold brazing furnace at one time. In a typical manufacturing operation of the hermetic terminal, batches of parts are placed into carbon/graphite holding/alignment fixtures called boats, the lead wires and alumina and gold pre-forms along with the ferrules are then all loaded into this special fixture. The operator then places these in a sealed chamber known as a vacuum brazing furnace. Then over a period of time, the temperature is raised sufficiently to re-flow the gold braze material. The gold makes a connection between sputtering, which was formerly placed on the alumina terminal 324 so that good wetting takes place, and a hermetic seal is formed. There is also a good wetting to the titanium such that a hermetic seal is formed there also. This can all be done in one continuous operation wherein the gold only wets to the titanium in the selected areas where the conductive polyimide 332 is to be placed. Accordingly, the structure as shown in 332 in FIG. 22 can all be formed in one manufacturing step with very little added cost. There is also an electrical advantage to doing it this way. By extending the gold bond pad over the greater area to include the hermetic seal portion of the gold braze, there is additional contact area of the gold to the titanium thereby further lowering the contact resistance related to the formation of oxides as previously mentioned herein. It has been demonstrated that the formation of these oxides can reduce the effectiveness of an EMI filter at high frequency. This is because the titanium oxide would increase the capacitor's equivalent series resistance thereby adding an undesirable resistance in series with the bypass capacitor.
Speaking specifically to U.S. Pat. No. 5,867,361 (Wolf, et al) dated Feb. 2, 1999, FIG. 1 of the Wolf patent discloses a gold braze 40 for connection of the conductive polyimide 47 to the titanium ferrule. Wolf indicates that the insertion loss or high frequency performance of the EMI filter is improved by connection to this gold bond pad. FIG. 9 illustrates the attenuation in decibels with and without a gold bond pad 40. In the Wolf patent, the hermetic seal is made between the alumina insulator using a gold braze shown in FIG. 1 as item 15. The gold braze 15 connects between the ferrule 93 and the alumina insulator 25. There is also a hermetic and electrical connection made between the lead wire 29 and the alumina insulator through gold braze 90. It is significant that the entire hermetic seal is formed in this lower region of FIG. 1. The attachment to the filter capacitor 50 is made using conductive polyimide 47 which is attached to the ferrule 93 by way of the gold brazed material 40. In the Wolf patent, the gold braze material is an area completely separate and distinct from the gold braze material 15 which is used to form the hermetic seal. Accordingly, this is done in two operations or two steps involving two separate gold brazed pre-forms. There is no hermetic seal between the ceramic capacitor 50 and the ferrule 93. In fact, any material used to make electrical connection between the ceramic capacitor and the ferrule is described as a conductive thermalsetting material, such as a silver filled polyimide or a solder or the like. None of these are suitable biocompatible sealing materials for human implant applications and they certainly do not make a hermetic seal (nor does solder since it is not considered a biocompatible material).
It is a novel feature of the present invention, as shown in FIG. 22 , that the hermetic seal and the gold bond pad is integrated into a single monolithic structure.
FIG. 23 illustrates a surface mounted quadpolar feedthrough capacitor 400 . A gold braze bond pad area 446 has been added to facilitate the connection between the capacitor outside diameter metallization 414 and the titanium ferrule 418 . As mentioned before, this connection can be made as in the past with a thermalsetting conductive adhesive 432 or with solder or the like.
FIG. 24 is a cross-section of the quadpolar feedthrough filter capacitor terminal of FIG. 23 . The gold braze area 446 or optionally 446 ′ has been extended and widened so that the capacitor outside diameter electrical connection 432 will touch off between the capacitor outside diameter metallization 414 and the gold braze surfaces 446 or 446 ′. By having an electrically conductive metallurgical joint directly between the capacitor metallization and the gold braze, there is no chance for any titanium oxide build-up to affect the capacitor's performance.
Another inventive concept illustrated in FIG. 24 is the electrical connection 444 between the lead wires 416 and the capacitor metallization 410 and gold braze 428 , 428 ′. This has been made possible by use of a thermalsetting insulative material 448 .
A unique design constraint affecting filtered hermetic terminals for implantable medical devices is that these devices are designed to be welded into the overall titanium housing of a pacemaker, implantable defibrillator or the like. Accordingly, the feedthrough capacitor assembly is subjected to a great deal of heat and thermal stress. Thus, the insulative material 448 has to withstand very high temperature. One such insulative material 448 is a unique thermal plastic polyimide supportive tape (coated with thermalsetting adhesive) manufactured by Ablestik Electronic Materials and Adhesives, (the mechanical properties of which are listed in FIG. 25. ) This material, which is known as Ableloc 5500, is unique in that it has the high temperature characteristics of a polyimide and yet will not flow. In other words, it stays in place, which allows one to form the novel structure shown at 448 .
It is very important that the bottom or the surface between the capacitor 400 and the alumina insulator 424 be sealed so that conductive materials or fluids cannot run between the capacitor pins and short it out. The Ableloc 5500 is ideal in that it forms a seal while remaining in place. This means that for the first time the present invention can guarantee that the capacitor inside diameter connection can be between the capacitor metallization 410 and the gold braze 428 or 428 ′, which opens up entirely new possibilities. For the first time niobium or tantalum pins can be utilized, without preparatory and secondary processing operations which are required because these materials are notoriously covered with oxide. No longer must there be a direct connection between the capacitor metallization 410 and the pin 416 itself. Instead, the gold braze 428 or 428 ′, which forms the hermetic seal, makes an oxide free metallurgical and very low resistance connection to the pin itself (in a one step operation). Accordingly, the electrical connection 444 between the pin 416 as shown in FIG. 24 is actually from the capacitor inside diameter metallization 410 directly to the gold braze 428 . The presence of oxides on the pin simply doesn't matter since a very low resistance electrical connection has already been formed. This electrical connection is also RF tight allowing the feedthrough capacitor to operate at very high frequency as a proper EMI filter.
FIG. 26 represents a prior art feedthrough capacitor 500 typical of U.S. Pat. No. 4,424,551 and related patents. The bottom surface of the capacitor 500 has been flooded with a nonconductive epoxy 550 . As exemplified in U.S. Pat. No. 4,424,551, the insulative material 550 is cured so that the capacitor 500 is bonded into the case 518 . Subsequent to this, the entire surface above the capacitor 500 is flooded with conductive polyimide material 532 , which is then centrifuged into place. It is very important during the centrifuge operation that material not flow underneath the capacitor thereby forming a short between the ferrule and the capacitor inside diameter pin 516 . An optional insulative epoxy coating 552 could be added to cosmetically cover the surface of the capacitor 500 and offer it some degree of mechanical protection. As can be seen in this prior art assembly, there is no way for the conductive polyimide 544 at the inside diameter to reach the gold braze 528 . Also, it is not possible for the outside diameter conductive polyimide 532 to reach the gold braze 530 . This type of prior art assembly is sensitive to any type of titanium oxide build-up that may occur on the inside diameter of the titanium ferrule.
FIG. 27 illustrates another prior art feedthrough capacitor 600 and related structure. This unit has a substantial oxide layer 634 on the inside of the titanium ferrule 618 . For simplicity, this oxide layer is only shown on the inside diameter of the ferrule 618 where the electrical connection to the capacitor ground metallization 614 is made (in actual practice, the oxide would to some degree coat all of the ferrule surfaces). Accordingly, there will be a high resistance between the conductive polyimide 632 and the titanium ferrule 618 . In this case the gold brazes 628 and 630 are shown on the opposite side away from the feedthrough capacitor 600 . Accordingly, there is no way in this structure for the feedthrough capacitor ground polyimide connection to have contact with the gold braze 630 . Thus, this prior art assembly is subject to EMI filter performance degradation if the oxide layer becomes too thick. Product life is another concern. Oxides can build up very slowly over time and lead to a latent type of design defect.
FIG. 28 illustrates the novel technology of the present invention as applied to the basic structures illustrated in FIGS. 26 and 27 . The unique Ableloc 5500 or equivalent high temperature thermal plastic polyimide supportive tape 748 allows the nonconductive insulating material to be held in place as shown (B staged epoxy washers could also be used, however, their temperature rating is not as high). This allows clear access for the conductive polyimide 744 or 732 to penetrate and contact the gold braze area 746 . In this case, it is important that the gold braze be on the capacitor side of the insulator 724 . The assembly shown in FIG. 28 no longer requires that the pin(s) 716 be restricted solely to platinum iridium or other non-oxidizing materials. This allows the use of much lower cost niobium or tantalum pins. The electrical connection can be between the capacitor inside diameter metallization 710 directly to the gold braze 728 itself. Accordingly, there is no need for an electrical connection between the capacitor inside diameter metallization 710 and the lead wire 716 at all. It can also be clearly seen in FIG. 28 that it would not matter if the inside diameter of the ferrule 718 was heavily oxidized. This is because there is an electrical connection directly from the capacitor outside diameter metallization 714 to the outside diameter gold braze 730 .
FIG. 29 is a broken out enlarged view of the outside diameter connection of FIG. 28 . As one can see, there is an oxide layer 734 which would tend to insulate the conductive polyimide or solder 732 from the titanium. However, because of the proper location of insulative material 748 , the conductive polyimide, solder or the like 732 can make direct contact between the capacitor metallization 714 and the gold braze area 730 . Sputtering 754 of metals on the alumina insulator 724 are required before the gold braze hermetic seal typically can be formed. This allows the gold braze material 730 to wet to the alumina insulator 724 and form a hermetic seal.
FIG. 30 is an enlarged view of the electrical connection to the lead wire 716 of FIG. 28 . It is assumed that a type of lead wire is used, such as tantalum or niobium, which would be heavily oxidized 734 . Not only are these oxides highly insulative, but they also do not form a solderable surface. However, a feature of the invention is that during hermetic seal construction, the oxides are absorbed by the metallurgical bond formed between the gold braze area 728 and the pin 716 . This is the same gold braze that forms the hermetic seal to the alumina insulator 724 . A sputtered layer 754 allows the gold to wet to the insulator 724 . As one can see, no direct connection between the capacitor metallization 710 and the lead wire 716 is required. Instead, the connection to the capacitor is accomplished by the thermalsetting conductive adhesive or solder 744 which connects from the capacitor metallization 710 directly to the gold braze 728 . Since the gold braze 728 has a metallurgical low resistance and low impedance connection to the pin, no further connection is required. In the case of a non-oxidizing pin material such as platinum, gold or platinum-iridium alloy, it is not necessary to form the structure as illustrated in FIG. 30 . In other words, the insulative washer 748 could extend all the way across the inside diameter thereby blocking access to the gold braze.
The most critical element in a medical implant feedthrough design (that must remain hermetic throughout it's device service life) is the metal/ceramic interface. Important are the nature of the bond itself and the sensitivity of the bond integrity to environmental conditions imposed as a result of the device fabrication process (like installation by laser welding by the pacemaker manufacturer) or as a part of environmental conditions developed while in service (body fluid is highly corrosive). For a braze-bonded feedthrough, the bond needs to deform in a ductile manner when environmental conditions create stresses (e.g., heating and cooling cycles that develop during device assembly welding). Typically, metallization and braze material combinations develop alloys that solidify as intermetallics. These intermetallics often show only modest ductility prior to failure. If material combinations are not judiciously selected and processes are not understood and controlled, significant dissolution can occur, and brittle fracture of the bond, or latent failures (static fatigue) result compromising hermetic integrity of the feedthrough.
A unique challenge for formation of the novel bond pads of the present invention is that they are formed as an integral part of the hermetic seal joint. This requires a relatively large amount of gold braze material (or other noble metal) to be used. In prior art EMI filtered human implant hermetic seals, the volume of braze material is by design relatively small. In the present invention, with the larger volume of braze material that is required, higher stresses due to shrinkage and mismatches in the thermal coefficient of expansion (TCE) of the braze material become a major design challenge. The biggest concern is the added stress in tension or shear which is transmitted to the metallic layer on the alumina hermetic seal/insulator (this layer is what allows the braze material to wet to the alumina and form the hermetic seal and is preferably applied by sputtering or equivalent methods). Unfortunately, the TCE of the high alumina content ceramic insulator does not match the TCE of any of the noble metal braze materials. Accordingly, for formation of the novel integrated gold hermetic seal/bonding pad as described herein, a unique metallization is required to be used in combination with the present invention that has high malleability and very high adhesion strength to the alumina ceramic and will also wet well to the braze material. It is a feature of the present invention that the preferred metallization on high alumina ceramics for miniature medical implantable device hermetic terminals, is titanium/molybdenum. Titanium is the active layer, and molybdenum is the barrier layer controlling how much titanium can actually dissolve in the gold. For example, 2-4 microns of titanium can be sputtered followed by 2-4 microns of molybdenum. The thickness will be dependent on the design, the application, and the subsequent potential environmental exposures. In this example, the titanium layer provides the interaction with the glass phases and alumina particle matrix of the ceramic to create a hermetic bond. The molybdenum layer protects the titanium layer from excessive oxidation prior to brazing and acts as a barrier between the gold braze material and the titanium layer. Without the molybdenum barrier layer, an excessive length of exposure of the titanium layer to the molten gold would accelerate the inherent alloying process and eventually lead to de-wetting, then hermetic failure
The titanium/molybdenum metallization in concert with gold braze, therefore, not only provides a sound hermetic bond, but also provides a sufficiently ductile materials feedthrough system to sustain secondary device assembly processes or environmental conditions that might develop stresses while the device is in service.
Other metallization materials that can be used with gold braze materials include but are not limited to titanium, niobium, chromium, zirconium, or vanadium active materials with molybdenum, platinum, palladium, tantalum or tungsten barrier layers in various combinations. Sputtering is one metallization application method. Other methods that might be used include but are not limited to chemical vapor deposition, laser or other physical vapor deposition processes, vacuum evaporation, thick film application methods, plating, and so on.
FIGS. 31-36 illustrate an internally grounded bipolar rectangular feedthrough capacitor 800 as described in U.S. Pat. No. 5,905,627. The center hole is the grounded hole 858 which would connect to the capacitor internal electrode plates 808 . More specifically, the feedthrough filter capacitor 800 comprises a monolithic, ceramic internally grounded bipolar feedthrough filter capacitor having three passageways extending therethrough. The outer two passageways 856 are configured to receive therethrough respective conductive terminal pins 816 ′ and 816 ″, and the internal diameter of the first passageways 856 are metallized 810 to form a conductive link between the active electrode plates 806 . As is well understood in the art, the active electrode plates 806 are typically silk-screened onto ceramic plates forming the feedthrough filter capacitor 800 . These plates 806 are surrounded by an insulative ceramic material 804 that need not be metallized on its exterior surfaces.
Similarly, ground electrode plates 808 are provided within the feedthrough filter capacitor 800 . The inner diameter of the central or second passageway 858 through the feedthrough filter capacitor 800 is also metallized 811 to conductively connect the ground electrode plates 808 , which comprise the ground plane of the feedthrough filter capacitor 800 . The second passageway 858 is configured to receive therethrough the ground lead 860 which, in this particular embodiment, comprises a ground pin.
With reference to FIG. 32 , the terminal pin subassembly comprises a plate-like conductive ferrule 818 having three apertures therethrough that correspond to the three passageways through the feedthrough filter capacitor 800 . The conductive terminal pins 816 ′ and 816 ″ are each supported through the outer apertures by means of an insulator 824 (which also may be hermetic), and the ground pin 860 is supported within the central aperture by a suitable conductor 830 such as gold brazing, solder, an electrically conductive thermalsetting material or welding/brazing.
The feedthrough filter capacitor 800 , as shown, is placed adjacent to the non-body fluid side of the conductive ferrule 818 and a conductive attachment is effected between the metallized inner diameter of the first and second passageways 856 and 858 through the feedthrough filter capacitor 800 and the respective terminal pins 816 and ground lead 860 . Alternatively, the capacitor 800 could be placed adjacent to the body fluid side of the conductive ferrule 818 provided the capacitor comprises a design incorporating biocompatible materials. In FIG. 35 , the conductive connections 844 between the terminal pins 816 and the ground lead 860 , with the feedthrough filter capacitor 800 may be effected by any suitable means such as a solder or an electrically conductive thermalsetting material or brazing. The result is the feedthrough filter capacitor assembly illustrated in FIGS. 35 and 36 which may then be subsequently laser welded into the titanium housing of an implantable medical device.
FIG. 35 illustrates the internally grounded bipolar feedthrough capacitor 800 of FIG. 31 mounted to the hermetic feedthrough terminal 802 of FIG. 32 . The ground lead 860 can be shortened so that it does not protrude through the capacitor 800 or it can be lengthened depending on whether or not a circuit attachment is required within the implantable medical or other electronic device. If the lead wires are solderable (platinum or gold), then the connection between the lead wires and the capacitor inside diameter metallization can be accomplished using solder, conductive adhesive or the like. A feature of the internally grounded feedthrough capacitor 800 is that no outside diameter (or perimeter in the case of FIG. 35 ) electrical connection or capacitor metallization is required.
FIG. 36 is a cross-section of the capacitor assembly of FIG. 35 . This illustrates several novel features of the present invention that are applicable to the internally grounded feedthrough capacitor, especially when lead wire materials that are subject to oxidation are used (such as niobium or tantalum). As one can see, the thermal plastic polyimide supportive tape 850 has been carefully punched, die-cut, or laser cut to align with the capacitor such that the capacitor feedthrough holes are open to the gold braze material 830 underneath. This allows a direct connection of the solder or conductive polyimide 844 to connect directly between the capacitor metallization 810 , 811 and gold braze material 830 . Accordingly, this opens up a wide variety of lead materials for use, which could not be considered before due to their heavy oxidation or poor solderability properties. This also allows the use of a ground pin of alternate materials, like titanium. A titanium ground pin is desirable because it is very easy to weld a titanium pin into a titanium ferrule. In the past, it was not possible to solder directly to titanium, however, a feature of the present invention is the capability of connection to the gold braze area. It should be apparent that not all leads are required to be constructed of the same material. For example, the center (ground) lead 860 could be titanium and the two active pins 816 ′ and 816 ″ could be platinum. In this case, it would not be required that conductive material 844 adjacent the platinum pins 816 ′ and 816 ″ contact the gold braze 830 .
FIG. 37 illustrates a novel hybrid capacitor 900 which has the characteristics of a conventional surface mounted feedthrough capacitor and an internally grounded capacitor. This capacitor 900 has a ground hole 958 in the center which connects to the internal ground electrode plates 908 and also has ground terminations 914 at either end. The reason for this is that this capacitor has a form factor which tends to increase its inductance and impedance. Accordingly, if one were to only make connection to the ground electrodes 908 shown in FIG. 38 at the center hole 958 , there would be too much inductance between this and the outer pins to perform effective EMI filtering. This hybrid design is best illustrated by the ground electrode plate pattern as shown in FIG. 38 , wherein the ground electrode 908 is attached to the titanium ferrule 918 at both the right and left ends and also in the middle. This guarantees that the capacitor 900 will have very low impedance across its entire ground plane thereby ensuring that it will work properly as a high frequency EMI filter. FIG. 39 is an illustration of the active electrode plate pattern 906 .
FIG. 40 illustrates the simplified hermetic terminal 902 . The centered ground pin 960 is welded or brazed 928 directly to the ferrule 918 . This forms a low resistance and low inductance ground connection to the pin 960 . The other pins 916 are shown in insulative relationship with the ferrule 918 . The novel gold bond pads of the present invention are shown as 946 . Restated, the ground pin 960 has been solidly brazed directly to the ferrule 918 . This provides a very low impedance RF ground between the center pin 960 and the overall electromagnetic shield. One can also see in FIG. 40 that the gold bond pads 946 have been added on either end to form a convenient surface for the electrical connection between the capacitor end terminations 914 and the ferrule 918 . It can also be seen that the other four pins 916 on both the right and left sides of the capacitor 900 are in electrically insulative relationship. This is done through the insulators 924 which can be glass or a gold brazed alumina seal.
FIG. 41 is a top view of the capacitor of FIG. 37 mounted to titanium ferrule 918 . The novel gold braze ground pads 946 of the present invention have been added so that an oxide free electrical connection can be made between the capacitor-ground terminations 914 and the conductive ferrule 918 .
FIG. 42 is a cross-sectional view of the capacitor 900 assembled to the hermetic terminal 902 of FIG. 40 . As shown, the gold bond pads 946 are also part of a single monolithic structure forming the hermetic seal between the ferrule 918 and the insulator 924 , in the same manner and for the same reasons as discussed above in connection with FIG. 22 . The connection between the capacitor ground metallization 914 (at its two ends) and the gold bond pads 946 is shown as material 932 , which can be solder, conductive thermalsetting material, or the like. The connection to the centered ground pin 960 is illustrated by material 944 which can also be solder, conductive thermalsetting material, or the like. As previously mentioned, in the present invention it is desirable to form insulative material 948 such that the electrical connecting material 944 adjacent to the ground pin 960 will directly contact the gold braze 928 . This is particularly important for ground pin lead materials that are not readily solderable or that form insulative oxide layers. The novel gold bond pad area 946 as previously mentioned could also be accomplished by sputtering, plating and the like.
As illustrated in FIG. 42 , for comparison purposes, the hermetic terminal 902 includes two distinctly different sets of lead wires 916 . To the left of the ground pin 960 , the lead wires 916 are shown as comprised of low cost niobium or tantalum pins on which heavy oxides typically form. When utilizing such low cost pins, the pads of oxide resistant conductive biostable material, noble metal, or the like, 946 are utilized to provide both a hermetic seal between the pins and the insulator 924 , and also to provide a reliable electrical connection between the interior termination surfaces 910 and the leads 916 , as discussed above in connection with FIGS. 24 , 28 - 30 and 36 . In contrast, the lead wires 916 to the right of the ground pin 960 are all platinum. As a noble metal, platinum is not subject to oxidation. Accordingly, it is not necessary for the solder or conductive polyimide used to connect between the capacitor inside diameter metallization and the lead wire to also contact the gold braze material 928 . In other words, an oxide free electrical connection has already been made between the capacitor inside diameter metallization 910 and the lead wire 916 , therefore it is not necessary to modify this assembly to contact the gold braze. However, in accordance with the invention, the aforementioned polyimide supportive tape 948 or the like could be placed to allow direct contact from the ground pin 960 to the gold braze 930 thereby allowing the use of a ground lead wire such as titanium, niobium or tantalum.
FIG. 43 shows a hybrid capacitor 1000 which has a centered ground pin 1060 and, because of its length and the desire to reduce inductance, is also grounded at its right and left ends using conductive polyimide 1032 to the gold bond pads 1046 . This is a hybrid in that it incorporates the features of both U.S. Pat. Nos. 5,333,905 and 5,095,627. FIG. 43 illustrates novel wire bond pads that overcome all of the obvious deficiencies of the aforementioned Wolf patent. The preferred location for the hermetic braze between the insulators 1024 and the hermetic terminal 1002 is at the pads 1046 . This takes the gold braze away from the body fluid both at each terminal pin and also at the hermetic seal joint to the ferrule. When a header block, which is commonly used in the industry is attached, silicone or other material is utilized which will fill the space between the lead all the way down to the gold braze. This effectively blocks the ready access of body fluids to the gold braze thereby preventing reverse electroplating involving material deposition to some other surface in the presence of a voltage bias. In other words, the location of the hermetic seal shown in FIG. 43 will overcome any problem with long term exposure to body fluid.
FIGS. 43 and 44 further illustrate an extruded nail head lead 1016 of bio-compatible material such as a noble metal including platinum, platinum iridium, gold and the like. The nail head portion 1062 of the lead 1016 on the bottom or body fluid side could be extruded as one piece particularly with a malleable material welded in place, brazed in place, or adhesively secured in place to the lead 1016 . The capacitor 1000 is attached to the terminal 1002 using similar processes as described above, and the leads 1016 are attached at the time that the hermetic seal joint 1046 is formed. During capacitor attachment the leads 1016 are allowed to stick through the capacitor 1000 as shown. At this point there are a number of options for the assembly. One option would be to make a solder joint, braze, weld or a thermalsetting conductive adhesive joint 1099 between the capacitor inside diameter termination and the nail head terminal pin 1016 . One could then add a wire bond closed pad or cap 1064 and attach it by soldering, welding, thermal conductive adhesive brazing or the like 1098 . The wire bond pad 1064 does not need to be bio-compatible and could be made of a number of inexpensive materials including nickel, copper, steel and the like. For wire bond applications it is usually required that the wire bond pad 1064 be pure (soft) gold plated, but a number of other surface finishes can be applied as well. The wire bond pads/nail head assembly 1016 , 1064 could also be formed from the group of metals including: tantalum, molybdenum, titanium, rhodium, titanium alloys, osmium, silver and silver alloys, vanadium, platinum, niobium, platinum alloys, stainless steel, tungsten, rhenium, zirconium, vanadium and ruthenium.
FIG. 45 illustrates an internally grounded hex polar capacitor 1100 embodying the invention (refer to U.S. Pat. No. 5,905,627). In this particular device, the novel wire bond pads 1164 as previously described have been utilized. The nail head pin 1116 is of the same group of materials as previously described for FIG. 43 . However, in this embodiment the hermetic seal 1146 has been moved to an alternate location and is now closer to exposure to body fluids. This is also acceptable to many customers but is not the preferred embodiment for maximum resistance to long term decomposition by metal migration.
The wire bond pad 1164 on the inside of the implantable medical device has also been modified so it has an open hole. In this case this a ring structure which is slipped over the bio-compatible pin 1116 and then attached by soldering, welding, brazing, or thermalsetting conductive adhesive or the like. An advantage of this structure is it is a little bit easier to assemble and inspect. A disadvantage is that the area available for customer attachment of their lead wires by ultrasonic wire bonding, thermal sonic welding or direct welding has been reduced. In other words there is less flat surface area available for customer lead attach.
Referring to FIG. 47A , a different embodiment of attachment of the lead wire 1160 is shown. In this case the lead wire 1160 extends through a toroidal ring 1164 ′ which may be constructed of various materials from the group of metals, and ceramics. One preferred embodiment would be the use of alumina ceramic which was metallized. This would allow one to form the electrical connection shown while at the same time allowing the lead wire 1160 to protrude through. In this case the very end of the lead wire 1160 could be the wire bond pad itself. There are a number of supplementary processes available after the extrusion of this lead wire to provide a flat and parallel surface. This has a number of advantages that will be obvious to one skilled in the art including the ability to readily inspect the joints.
More particularly, the preferred metallized alumina toroidal ring 1164 ′ has been metallized on all surfaces so it is both solderable and conductive. Solder, thermalsetting conductive adhesive, welding or the like 1168 performs an electrical connection between the circular torroid 1164 ′ which in turn connects to the capacitor 1100 active electrode plates 1106 . In addition, material 1170 , which can be of the group of solder, thermalsetting conductive adhesives, welding, brazes or the like, forms the electrical connection between the lead wire 1160 to the torroidal structure 1164 ′ which then couples through the electrical connection 1168 via the capacitor metallization 1110 to the electrode plates. As shown the tip of the lead wire 1172 is flat to accept lead attachment by the customer by wire bonding, thermal sonic bonding, laser welding or the like. A supplementary nail head or enlarged area could be added to the tip 1172 to increase the surface area available for such customer lead attachment operations. One particular advantage of the structure shown in FIG. 47 is the ability to select a material that closely matches a thermal co-efficient expansion of the ceramic capacitor 1100 . Such materials include fosterite, zirconium, gold alloys, or materials such dumet.
Capacitor 1100 has inside diameter metallization 1197 at each of the seven inside diameters to make electrical connection to the ground and active electrode plate sets. This metallization also appears on top of the capacitor as a circular mounting/bonding pad 1199 . In this case, there is no need to fill the space between the capacitor inside diameters and the noble metal lead wires with an electrical connection material.
FIG. 47B shows that the lead wire and its electrical connection may be subflush or below the top of the ring pad 1164 . In this case, the ring pad forms the wire bond surface.
As shown in FIG. 47C , the electrical connection is formed between pin 1116 and the capacitor top metallization 1199 using solder, braze, conductive adhesive or the like. Alternative connections using a variety of wire bond pad end caps are shown in FIGS. 47A , 47 B, and 47 C.
FIGS. 48 and 49 show an externally grounded quadpolar device. While a compatible nail head pin 1216 is utilized and in this case, the hermetic seal connection 1246 between the alumina ceramic 1224 and the nail head pin 1216 is in the preferred location. Drawing attention now to the wire bond end cap 1264 , a different attachment method is contemplated. This attachment method is desirable in that it completely eliminates the necessity for any contact materials or any solder or other materials to be placed between the lead wire 1216 and the inside diameter termination of the ceramic capacitor 1200 . In this case the capacitor 1200 inside diameter metallization 1210 is also formed as a circular structure on the top surfaces of the ceramic capacitor. This is commonly used in the connector industry and with planar arrays. Such structures are normally printed on the top surface of the ceramic capacitor by silk screening processes or the like. Accordingly, it is easy to form this on the top surface of the capacitor 1200 . This makes the attachment of the end cap 1264 very simple and easy to facilitate in a manufacturing operation. As best seen in FIG. 49 , attachment of the wire bond cap 1264 is simply accomplished by making a solder joint, conductive thermalsetting adhesive joint, braze joint, weld joint or the like shown as 1266 . This makes a direct connection to the capacitor termination 1210 . Accordingly, there is no other connection to the capacitor inside diameter that is needed. At the same time that the joint 1266 is formed or at a different time, the electrical connection 1299 to the end cap 1264 is also made. As previously mentioned, this can be done thermalsetting conductive adhesives, solder, brazes, welds or the like.
This is a major advantage over the aforementioned Wolf patent in that the inside diameter of the capacitor does not have any materials that mis-match it in its thermal co-efficient of expansion. Accordingly, the capacitor will be mechanically more rugged and more resistant to thermal shock such as those induced by the customer during installation by laser welding. The capacitor termination materials are preferably in this case formed from either plating or a fired on silver or a palladium-silver glass frit. These are put on as a thick film process sufficient so that it forms a mechanically rugged and electrically reliable attachment to the capacitor active electrode plates 1206 .
Although several embodiments of the invention have been described in detail for purposes of illustration, various modifications of each may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited, except as by the appended claims. | EMI feedthrough filter terminal assembly includes a feedthrough filter capacitor having first and second sets of electrode plates, and a first passageway having a first termination surface conductively coupling the first set of electrode plates. At least one lead wire extends through the first passageway and is conductively attached to a first oxide resistant conductive pad. The first pad is conductively coupled to the first termination surface independently of the lead wire. The terminal assembly may also include a conductive ferrule through which the lead wire passes in non-conductive relation, and an insulator fixed to the ferrule for conductively isolating the lead wire from the ferrule. The ferrule and insulator form a pre-fabricated hermetic terminal pin sub-assembly. The capacitor may include a second passageway having a second termination surface conductively coupling the second set of electrode plates, and a conductive ground lead extending therethrough. | 7 |
BACKGROUND OF THE INVENTION
Many times it is desirable to form a strand consisting of a very large number of filaments. Generally, a number of smaller strands consisting of a plurality of filaments in each are combined in a roving process to produce a single large strand or roving of a large number of filaments. To accomplish this, filaments are pulled from a feeder and wound upon a forming tube being rotated by a winder to form a subpackage. Such subpackages are positioned as a group to remove each of the strands therefrom to combine the substrands into a larger strand by the action of yet another winder as is known in the art. Or the combined strand can be pulled by the action of a cot wheel and a chopper to deliver a large number of continuous filaments to be cut into discrete segments.
Generally, a reduction in the equipment utilized in the steps employed in producing such a strand containing a large number of filaments can lead to improved efficiencies and reduced costs. This is especially practical wherein all of the filaments can be attenuated by the action of a single attenuation means located on a single level of a forming room.
Systems for producing chopped glass segments from a plurality of spaced apart bushings have been employed before. But, due to the orientation of the bushings, coating applicators, gathering shoes, idler rolls, and scrap pull rolls and the like, a strand break out could disrupt at least a portion of the remaining forming operation, if an intermediate forming section was disrupted.
Furthermore, in the production of discrete fibers or chopped strand, it is desirable to concomitantly pull continuous glass fibers from a plurality of spaced apart feeders adapted to supply a strand or plurality of strands to the chopper wherein the cot wheel of the chopper acts as a pull wheel to attenuate the streams of molten material issuing from the feeders into filaments. In drawing the filaments from a plurality of bushings to be advanced through the chopper, it is possible to maintain production from a number of bushings even though one or more bushings may be disrupted. With the bushings and other apparatus oriented to provide continuous operation in spite of a disruption of one or more bushings, it is desirable to have the operator restart the disrupted feeder to again supply filaments to the chopper in the absence of disrupting the other bushings.
To accomplish this, the filaments must be continuously attenuated from all bushings still in operation. Thus, the chopper can not be stopped. However, with high speed operations it is difficult and sometimes undesirable to try to rethread the chopper at high speed. Therefore, the rotational speed of the chopper must be reduced to allow the operator to rethread the strand but yet maintain a speed sufficient to attenuate filaments from the other bushings to prevent substantial disruptions therein.
At the reduced speed, however, the discrete fibers formed may not be of the proper size or quality desired. To insure that the secondary or waste discrete fibers are not placed in the receptacle containing the desired chopped strand/fibers it is necessary that the secondary fibers be directed elsewhere.
SUMMARY OF THE INVENTION
This invention pertains to a method and apparatus for forming and collecting discrete segments of fibrous glass comprising supplying a plurality of streams of molten glass; attenuating the streams into filaments and cutting the continuous filaments into discrete segments by a forming means; positioning a delivery means having a first collection zone and a second collection zone spaced from the first zone to receive said discrete segments; controlling said forming means to operate at a first speed or a second speed slower than the first speed; directing the discrete segments to said first zone when said forming means is operated at said first speed and to said second zone when said forming means is operated at said second speed.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the multifeeder forming system according to the principles of this invention.
FIG. 2 is a side view of the system showing FIG. 1.
FIG. 3 is a plan view of the forming system shown in FIG. 1.
FIG. 4 is a semi-schematic front elevational view of a chopper according to the principles of this invention.
FIG. 5 is a partial side view of the system shown in FIG. 4.
FIG. 6 is a portion of an electrical control diagram for the apparatus of FIGS. 4 and 5.
FIG. 7 is a portion of the electrical control diagram for the apparatus of FIGS. 4 and 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIGS. 1, 2, and 3, the forming system is comprised of spaced apart continuous filament forming sections 4, 5, and 6 which are associated with a primary attenuation means or chopped strand forming means 40. Thus, a single attenuation means is adapted to attenuate and advance all of the filaments from all of the forming sections. As such, the primary attenuation means 40 can be a winder, pull wheel, or a chopper for forming discrete fibers or chopped strand as is known in the art.
As shown, each forming section 4, 5, and 6 is comprised of a stream feeder or bushing 10, size or coating applicator 18, gathering shoes or guide means 22, an idler roll or guide means 30 and secondary attenuation means 50, all of which can be of the type well known in the glass fiber forming art.
In operation, each of the feeders 10 supply a plurality of streams of molten glass to be attenuated into filaments by the action of the primary attenuation means 40 or secondary attenuation means 50. In any glass fiber forming operation, occasionally, some of or all of the filaments from any bushing will break and the attenuation process will be halted. During restart, "bead down" can occur wherein the streams of molten material leave the feeder as beads of molten glass. If left unattended in a free fall condition, the beads or streams will move along a path defining a vertically extending zone beneath feeder 10.
To establish a continuous and efficient operation, it is imperative that such forming equipment as the applicators 18, gathering shoes 22, idler rolls 30, and scrap pull rolls or secondary attenuation means 50 be positioned external to such zone to keep such equipment out of the free-fall path of the beads or streams.
As shown in FIG. 2, applicator 18, gathering shoe 22, idler roll 30, and secondary attenuation means 50 are laterally spaced to the same side of zone 54. Generally, it is preferred that such equipment be on the side of the zone 54 opposite the side of the zone where the operator is normally positioned. With such an orientation, the operator has easy access to the bottom region of the feeder while permitting easy access to coating applicator 18, gathering shoe 22, idler roll 30 and scrap pull roll 50.
During production, feeders 10 of forming sections 4, 5, and 6 supply a plurality of streams of molten glass to be attenuated into continuous filaments 14, 15, and 16. Each of such filaments are advanced along a path external to the zone 54 of each of the plurality of forming sections. Each of the applicators 18 is fixed external to the zone and laterally spaced therefrom such that the applicator surface, which can be a rotatable roll wet with a suitable liquid size and/or coating, as is known in the art, is located laterally spaced from the zone. The liquid is applied to the filaments at a region laterally spaced from the zone.
Gathering shoes 22 are laterally spaced farther from the zone in the same direction as applicators 18 to bring the filaments into contact with the applicator roll. Gathering shoes 22 further serve to gather the filaments into a substrand and guide the strand along a path external to the zones 54. From gathering shoes 22 the substrands 26a and 26b, 27a, 27b, 28a, and 28b are advanced to idler rolls 30 associated therewith to form strands 26, 27, and 28 respectively.
Strands 26, 27, and 28 are advanced to second guide means 35 which is laterally spaced from the same side of zones of all of the forming sections 4, 5, and 6. Gathering shoes 22 can be considered a first guide means or the combination of gathering shoes 22 and idler rolls 30 can work in conjunction as a first guide means. The second guide means 35 is positioned in a horizontal plane below the horizontal plane or zone containing the first guide means such that the strands 26, 27, and 28 are maintained in a spaced apart relationship until such strands substantially reach second guide means 35. As shown in FIG. 1, second guide means 35 is located in a horizontal plane beneath the horizontal plane containing idler rolls 30 of sections 4, 5, and 6. With the strands 26, 27 and 28 remaining in a spaced apart relationship until approximately reaching guide means 35 it is easier to restart individual strands than if the strands were confined prior to that point.
Strands 26, 27, and 28 are then advanced as a larger strand to primary attenuation means 40. As shown in FIG. 1, primary attenuation means 40 is comprised of an idler roll 42, a cot roll 44, and a cutter roll 46 having a plurality of radially projecting cutting edges as found in choppers well known in the art. Cot roll 44 acts as a pull wheel and idler roll 42 is positioned to bring the strands into engagement with the surface of cot roll 44 in a non-slipping engagement such that all of the streams from all of the bushings 10 are simultaneously attenuated into filaments. As the strand contacting the surface of cot roll 44 passes through the region where cutter roll 46 pierces the elastomeric surface of cot roll 44 the continuous glass filaments or strands are cut into discrete segments.
As shown, second guide means 35 is positioned such that strands 26, 27, and 28 are all advanced along paths external to each of the zones 54 of sections 4, 5, and 6. Thus, if one of the sections should be disrupted at any time, the streams or beads thereof will not contact the remaining advancing strands and disrupt the entire operation.
During start-up or restart, the filaments can be normally in contact with the applicator 18, gathering shoe 22 and idler roll 30, with the strand being advanced as waste material since the secondary attenuation means 50 is normally of the type that the filaments are pulled at a lower speed than by the primary attenuation means.
As shown in FIG. 2, the secondary attenuation means or scrap rolls 50 are also positioned or laterally spaced to the same side of zone 54 as applicator 18. However, the secondary attenuation means is positioned closer to zone 54 than idler roll 30, such that the waste strand 56 is advanced downward and forward in the absence of contacting, for example strand 28, when an interior forming section, such as section 5, employs secondary attenuation means 50 to preclude the fouling of strands and/or interfilament abrasion.
It is preferred that the scrap rolls 50 be located closer to zone 54 than idler roll 30 because if the secondary attenuation means 50 was located a greater distance away from zone 54 in the same direction as idler 30 the operator would have to reach in past the high-speed advancing strands and bring the strand, which is about to be restarted, over or through the array of advancing strands which is not desirable.
Furthermore, each of the secondary attenuation means 50 is laterally spaced from its associated zone 54 such that, in systems employing substrands as shown herein, one of the substrands can break out and bead down without disrupting the pulling of the fibers from the other portion of the bushing 10.
Is is preferred that the feeders 10 of the forming sections 4, 5, and 6 be spaced apart and located substantially in a first, common vertical plane with each of the applicators 18 being located substantially in a second, common vertical plane laterally spaced from the first vertical plane. Gathering shoes 22 and idler rolls 30 are oriented such that they have substantially parallel axes of rotation such that the strand advancing downward between the surface of the applicator 18 and surface of idler rolls 30 moves in a third plan oblique to the first and second vertical planes with the third oblique plane being tangent to the surface of the applicator 18. That is, the feeders, applicators, gathering shoes, idler rolls, and secondary guides are positioned such that the advancing strands are external to all the zones 54 of the forming sections 4, 5, and 6 to promote continuous operation in spite of a break out in any of the forming sections.
It is preferred that idler rolls 30 and 42 be of the type wherein a plurality of substantially parallel, spaced apart cylindrical rods are fastened to at least one flange substantially perpendicular thereto adapted to be journally mounted for rotation along an axis substantially parallel to the rods. It is believed that, wherein "D" is equal to the diameter of the base circle through which the axes or center lines of the rods pass, "d" is equal to the outside diameter of the cylindrical rods, and "S" is equal to the distance measured along the base circle between the center lines of adjacent rods. Said idler roll should be fabricated according to the following parameters: d≦0.08D and S≧1.6d. And it is preferred that 0.08D≧d≧0.06D. Furthermore, it is preferred that 2.0d≧S≧1.6d.
In idler rolls having a central cylindrical shaft or sleeve extending along the axis of rotation located between the cylindrical rods it is preferred that the outside diameter of the central sleeve or shaft, "X", be ≦0.65D.
It has been found that idler rolls fabricated according to the foregoing parameters exhibit a substantially reduced tendency for the strands having a liquid thereon to "roll wrap". It is believed that the spacing between adjacent rods and the spacing between the cylindrical rods and the central sleeve, if any, promotes an air movement over the surface of the rods effective to wipe the surface of the rods clean to produce an idler roll having a reduced tendency to roll wrap.
As shown in FIGS. 4 and 5, first rotatable means or cot roll 44 is journaled in frame 132, and cutter roll or second rotatable member 46 is also journaled in frame 132. Chopper or primary attenuation means 40 serves to attenuate the streams of molten material into filaments through the action of the cot roll 44 which acts as a pull wheel and cut or chop the continuous filaments into discrete segments.
Drive means 140, such as a conventional electrical motor, is adapted to rotate cot roll 44 and cutter roll 46, and recepticle or delivery means 145 is positioned to receive the chopped strand 31 as the chopped strand leaves the forming means 40.
Recepticle 145 is comprised of a first zone 147 spaced from a second zone 149 by means of wall 151. Movable element 153 is pivoted at one end of wall 151 by means of rod 155 joined thereto and journaled in the side walls of the recepticle 145. Attached at one end of rod 155 is arm 157 which is attached at the opposite end to shaft 159 of motive means or air cylinder 161.
As shown in FIG. 4, movable element 153 is adapted to direct the chopped strand 31 to the second zone 149 of recepticle 145 when the shaft 159 is retracted. When the air cylinder 61 is energized to extend shaft 159, movable element 153 retracts into the normal operating position to allow the chop strand 31 to move to and through first zone 147. Generally, first zone 147 is adapted to direct the chop strand a suitable shipping container, while second zone 149 is in communication with a suitable scrap collection system.
During the operation of such multifeeder wet chop systems, it is desirable to maintain production from the feeders 10 in spite of process interruptions, such as break-outs and the like, from one of the other feeders. With high speed operations, it may be difficult and undesirable to rethread the disrupted feeder with the system operating at full speed. But the forming means or chopper 40 cannot be stopped, otherwise the other feeders will be interrupted. Therefore, the speed of the chopper, the cot roll and/or cutter roll must be reduced to a second speed, slower than the first speed, to allow the operator to thread-up the strand to be restarted and yet maintain the other bushings in an operational mode.
When the system is operating at the second or slower speed, the filaments and/or chopped strand formed may be of the type or quality unacceptable for inclusion with the desired product. To prevent the secondary chop strand or waste from contaminating the desired product, delivery means or recepticle 145 is adapted to direct the chopped strand to the first zone 147 when the forming means 40 is operating at the first speed and to direct the chopped strand 131 into the second zone 149 when the attenuation/forming means 40 is operating at the second or slower speed. This is accomplished by means of a control system coordinating the drive means 140 and the delivery means 145.
During operation when the operator is about to rethread a strand from a disrupted bushing, the operator activates the control system which reduces the speed of the forming system 40 and energizes air cylinder 161 to shift movable element 153 to direct the waste into the second zone 149. To prevent the system from running at the second speed for too great a length of time which may set up thermal imbalances in the other normally operating feeders, the control system is adapted to automatically shift back into the normal or high speed mode after a predetermined length of time. That is, a system is provided wherein normal production resumes after the strand has been restarted in the absence of further actions by the operator.
The control means which interconnects the motor 140 with the air cylinder 161 and thus movable element 53 to direct the filaments as described is schematically set forth in FIGS. 6 and 7 in the unenergized state. Leads X1 and X2 are adapted to be connected to a suitable source of electricity. With stop switch 170 in the closed position and start switch 172 momentarily depressed, coil F is energized which closes contacts F2 to lock in the magnetic starter coil F located in motor 40. Also when coil F is energized, contacts F-1 open thus denergizing relay CR3 and scrap chute solenoid valve SV, assuming that auto/manual switch 177 is in the automatic position.
Solenoid valve SV is connected to a suitable source of pressurized air (not shown) and to the air cylinder 61. When the solenoid valve SV is denergized, movable element 153 is in the retracted position such that a direct path to first zone 147 for chopped strand 131 is established.
Referring to FIG. 6, it can be seen that when relay CR3 is denergized, contacts CR3-1 are in the closed position connected in series with slow/fast speed select switch 179 which is adapted to be closed in the fast position. Thus full power is delivered to motor M2 of drive means 140 to operate chopper 40 in the first or high speed mode.
Also movable element 153 can be shifted to direct any material entering recepticle 145 into second zone 149 by shifting the auto/manual switch 177 to the manual position to energize scrap chute solenoid SV which operates movable element 153.
Assuming that one of the feeders 4, 5, or 6 is about to be restarted with at least one other feeder operating under normal production conditions the operator activates spring loaded control switch 175 which energizes relay CR2 to close contacts CR2-1 and CR-2. With contacts CR2-1 closed relay CR2 is locked in until contacts T1-M are opened as will be explained later. As the spring loaded control switch 175 automatically returns to the normal position timer T1 is energized such that coil C in timer T1 is energized as well as timing motor M. Coil C in timer T1 is not timed but acts similar to a conventional relay such that contacts T1-C are closed instanteously upon the energization of timer T1 thus energizing relay CR3 and scrap chute solenoid SV. When scrap chute solenoid SV is energized, movable element 153 directs the chopped strand 31 into second collection zone 149, thus preventing any of the waste formed at the lower speed from contaminating the primary product.
The motor M2 of drive means 140 is shifted into the second or slower speed since contact CR3-1 opens when relay CR3 is energized. Thus the current must pass along resistors R1 and R2 located in series along one of the leads X3 and X4 leading to the motor to run the motor at the slower speed.
Timed motor relay M upon energization begins to count down for a preselected length of time. Contacts T1-M remain closed until timing motor M times out where upon contacts T1-M open thus denergizing relays CR2 and CR3.
Contacts T1-M remain open only for an instant, but timer T1 remains denergized since contacts CR2-2 have shifted to the open position because relay CR2 has been denergized. Thus, the movable element 153 in recepticle 145 is returned to the closed position permitting the chopped strand to move through the first zone 147. Simultaneously with the denergization of relay CR2, CR3 is denergized such that contact CR3-1 returns to the closed position to permit the chopper 40 to return to the high speed mode, assuming the speed select switch 179 is in the fast position. Thus, the system can continue to operate in the normal or high speed mode delivering chop strand 31 to the first zone 47 until the control switch 175 is activated again.
The contacts, relays, switches, timers, and motors employed herein can be of the type commercially available. For example, relays CR2 and CR3 can be Potter Brumfield catalog Nos. KRP14AG, 3PDT, and KRP11AG, DPDT, respectively. Control switch 175 can be Square D Company push buttom class 9001 type KR25G. Stop switch 170 and start switch 172 can be a Square D Company, push button class 9001 type KR-1U. Timer T1 can be a Cyib-Flex reset timer type HP50A6, and the auto/manual switch can be Square D Company switch class 9001 catalog number KS-11B. The motor M2 for the drive means 140 can be of the DC drive Sencore model no. 2450P50013A.
It is apparent that within the scope of the invention, modifications and different arrangements can be made other than is here and disclosed. The present disclosure is merely illustrative with the invention comprehending all variations thereof. | Method and apparatus for forming discrete segments of fibrous glass comprises supplying a plurality of streams of molten glass; attenuating the streams into filaments and cutting the continuous filaments into discrete segments by a forming means; positioning a delivery means having a first collection zone and a second collection zone spaced from the first zone to receive said discrete segments; controlling said forming means to operate at a first speed or a second speed slower than the first speed; directing the discrete segments to said first zone when said forming means is operated at said first speed and to said second zone when said forming means is operated at said second speed. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an earthquake warning method and an earthquake warning broadcast system thereof, and more particularly, to a local earthquake warning method and an earthquake warning broadcast system thereof.
[0003] 2. Description of the Prior Art
[0004] Considering casualties and property loss brought by earthquake, government and related organizations establish seismological monitoring centers to monitor detail information such as times, places, types, etc., of earthquake. However, since precise earthquake detecting instruments are quite expensive and not so popular, earthquake alarm messages, which are results detected by the seismological monitoring center, are broadcasted to people through the media such as television, radio, network, etc. However, the media broadcasting the earthquake alarm message is not timely enough and the information penetration rate thereof is low. People usually receive the earthquake alarm message after the earthquake occurred, such people are too late to take earthquake contingency measures and irreparable casualties and property loss are caused.
[0005] Even though there are small earthquake warning broadcast systems in the market, the price thereof is too expensive, in addition, the accuracy of which is intolerable and to be improved, such that false alarm might occur due to human factors. Therefore, it is necessary to improve the prior art.
SUMMARY OF THE INVENTION
[0006] It is therefore a primary objective of the present invention to provide an earthquake warning method and an earthquake warning broadcast system thereof, to reduce the cost of the earthquake warning broadcast system.
[0007] The present invention discloses an earthquake warning method. The earthquake warning method comprises deploying a set of earthquake detectors within a zone according to a specific rule to detect an earthquake wave; generating a first earthquake warning signal when the earthquake wave is detected; receiving the first earthquake warning signal and a second earthquake warning signal; performing a decision determination according to the first earthquake warning signal and the second earthquake warning signal; sending the first earthquake warning signal or the second earthquake warning signal to a plurality of warning devices according to the decision determination; and broadcasting an earthquake alarm.
[0008] The present invention further discloses an earthquake warning broadcast system. The earthquake warning broadcast system comprises a set of earthquake detectors, deployed within a zone according to a specific rule, for detecting an earthquake wave; a local earthquake detecting system, coupled to the set of earthquake detectors, for generating a first earthquake warning signal when the earthquake wave is detected; a central earthquake detecting system, for generating a second earthquake warning signal when the earthquake wave is detected; a decision unit, coupled to the local earthquake detecting system and the central earthquake detecting system, for performing a decision determination according to the first earthquake warning signal and the second earthquake warning signal, and sending the first earthquake warning signal or the second earthquake warning signal according to the decision determination; and a plurality of warning devices, coupled to the decision unit, for receiving the first earthquake warning signal or the second earthquake warning signal, and broadcasting an earthquake alarm.
[0009] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic diagram of an earthquake warning broadcast system according to an embodiment of the invention.
[0011] FIG. 2 is a schematic diagram of a process according to an embodiment of the invention.
DETAILED DESCRIPTION
[0012] Please refer to FIG. 1 , which is a schematic diagram of an earthquake warning broadcast system 10 according to an embodiment of the invention. The earthquake warning broadcast system 10 comprises a set of earthquake detectors 100 , a local earthquake detecting system 120 , a central earthquake detecting system 140 , a decision unit 160 and a plurality of warning devices 180 . The set of earthquake detectors 100 comprises at least two earthquake detectors, and are deployed within a zone Z according to a specific rule, for detecting a vertical acceleration of an earthquake wave. The local earthquake detecting system 120 is couple to the set of earthquake detectors 100 , for generating an earthquake warning signal ES 1 . The central earthquake detecting system 140 is utilized for generating a second earthquake warning signal ES 2 when the earthquake wave is detected. Preferably, the central earthquake detecting system 140 may be a central seismological monitoring center established by the government and related organizations. The decision unit 160 is coupled to the local earthquake detecting system 120 and the central earthquake detecting system 140 , for performing a decision determination according to the earthquake warning signal ES 1 and the earthquake warning signal ES 2 and sending the earthquake warning signal ES 1 or the earthquake warning signal ES 2 to the plurality of warning devices 180 according to the decision determination. The plurality of warning devices 180 are coupled to the decision unit 160 , for receiving the earthquake warning signal ES 1 or the earthquake warning signal ES 2 , and broadcasting an earthquake alarm according to the earthquake warning signal ES 1 or the earthquake warning signal ES 2 . Preferably, each of the warning devices 180 may be a cheap electronic clock or any other electronic device producing sounds or images, and the earthquake alarm may be in a form of sounds or images instructing subscribers to escape or refuge, such that a damage caused by earthquake is lowered. Since the single local earthquake detecting system 120 is disposed within the zone Z and the earthquake alarm is broadcasted through the plurality of cheap warning devices 180 , all of the subscribers within the zone Z may receive the earthquake alarm when an earthquake occurs, such that casualties caused by the earthquake are lowered. Since the cost of deploying the local earthquake detecting system 120 may be shared by the subscribers, in comparison to the earthquake warning broadcast system in the prior art, more people are able to afford the earthquake warning broadcast system 10 of the present invention. Furthermore, the decision unit 160 is connected to both the local earthquake detecting system 120 and the central earthquake detecting system 140 , such that earthquake information may be exchanged. Therefore, accuracies of the earthquake warning signal ES 1 and the earthquake warning signal ES 2 may be mutually compared, so as to avoid occasions of false alarm.
[0013] In the embodiments of the present invention, the set of earthquake detectors 100 may be deployed according to a specific rule. The specific rule comprises a geographic parameter and a reference economic value, for example, a geological zone (e.g., a fault zone), an area (e.g., urban, suburban or mountain area), indoor/outdoor (including high/low floor), a population density, a unit economic value of building, a fragility of building, etc., which are not limited herein. Under a condition of the set of earthquake detectors 100 deployed near buildings with high economic value, the embodiments of the present invention may significantly reduce economic loss caused by the earthquake. Under a condition of the set of earthquake detectors 100 deployed in an area with high population density, the embodiments of the present invention may significantly reduce casualties caused by the earthquake.
[0014] In addition, performing the decision determination in the embodiment of the present invention may comprise determining whether the earthquake warning signal ES 1 and the earthquake warning signal ES 2 are higher than a triggering threshold TH, determining an arrival order of the earthquake warning signal ES 1 and the earthquake warning signal ES 2 , and determining an accuracy of the earthquake warning signal ES 1 and the earthquake warning signal ES 2 , wherein the triggering threshold TH may be configured according to user requirements. When the triggering threshold TH is configured as a low value, the earthquake warning system may urge the subscribers to escape and gain more time for escape, such that major damage is avoided. When the triggering threshold TH is configured as a high value, over-frequent alarms causing the subscribers nervous and false alarms are avoided. If the earthquake warning signal (e.g., ES 1 or ES 2 ) is lower than the triggering threshold TH, the decision unit 160 neglects the earthquake warning signal.
[0015] In order to make the earthquake warning more precisely, the decision unit 160 may perform analysis on the earthquake warning signal ES 1 and the earthquake warning signal ES 2 , and compare the accuracies of the earthquake warning signal ES 1 and the earthquake warning signal ES 2 with each other. In order to make the earthquake warning timelier, the decision unit 160 bases on the arrival order of the earthquake warning signal ES 1 and the earthquake warning signal ES 2 , and sends the earthquake warning signal which arrives first to the warning devices 180 .
[0016] In short, the set of earthquake detectors 100 should be deployed in the zone Z according to the specific rule such as geological structures, fault zone information, the unit economic value of building, etc. When the set of earthquake detectors 100 detects an earthquake occurs, the local earthquake detecting system 120 generates the earthquake warning signal ES 1 . Meanwhile, by cooperating with the central earthquake detecting system 140 , the earthquake warning signal ES 2 is received. When the decision unit 160 receives the earthquake warning signal ES 1 or the earthquake warning signal ES 2 , the decision unit 160 performs the decision determination to determine whether the earthquake warning signal ES 1 or the earthquake warning signal ES 2 is higher than the triggering threshold TH and neglect the earthquake warning signal lower than the triggering threshold TH. The decision unit 160 sends the earthquake warning signal which arrives first to the plurality of warning devices 180 according to the arrival order of the earthquake warning signals. When the warning devices 180 receive the earthquake warning signal (either the earthquake warning signal ES 1 or the earthquake warning signal ES 2 ), the warning devices 180 broadcast the earthquake alarm to prompt the subscribers in the zone Z. The subscribers in the zone Z may share the cost of deploying the local earthquake detecting system 120 , such that more subscribers utilize the earthquake warning broadcast system 10 of the present invention and the damage caused by the earthquake is significantly reduced.
[0017] The operating method of the earthquake warning broadcast system 10 can be further summarized into a process 20 , as shown in FIG. 2 . The process 20 may be utilized for performing earthquake alarm and comprises the following steps.
[0018] Step 200 : Start.
[0019] Step 202 : Deploy the set of earthquake detectors within the zone Z to detect an earthquake wave according to at least one of the geographic parameters and the reference economic values.
[0020] Step 204 : Generate the earthquake warning signal ES 1 when the earthquake wave is detected.
[0021] Step 206 : Receive the earthquake warning signal ES 1 and the earthquake warning signal ES 2 .
[0022] Step 208 : Perform the decision determination according to the earthquake warning signal ES 1 and the earthquake warning signal ES 2 .
[0023] Step 210 : Send the earthquake warning signal ES 1 or the earthquake warning signal ES 2 according to the decision determination.
[0024] Step 212 : Broadcast the earthquake alarm according to the received earthquake warning signal ES 1 or the received earthquake warning signal ES 2 .
[0025] Step 214 : End.
[0026] Details of the process 20 may be referred to related paragraphs in the above, which are not narrated herein.
[0027] In summary, the earthquake warning broadcast system of the present invention may broadcast the earthquake alarm to many subscribers within the zone through the cheap warning devices. The subscribers share the cost of deploying the local earthquake detecting system. In comparison to the expensive earthquake detecting system in the prior art, the embodiments of the present invention make the earthquake warning broadcast system affordable by more subscribers. In addition, the embodiment of the present invention connects to both the local earthquake detecting system and the central earthquake detecting system, and performs exchange of earthquake information. Therefore, occasions of false alarm are reduced and accuracy of the earthquake warning is enhanced.
[0028] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | The present disclosure provides an earthquake warning method. The earthquake warning method includes deploying a set of seismic device in a zone according to a criterion to detect an earthquake, generating a first earthquake warning signal when the earthquake is detected, receiving the first earthquake warning signal and a second earthquake signal; executing an decision determination according to the first earthquake warning signal and the second earthquake signal; sending first earthquake warning signal or a second earthquake signal according to the decision determination and broadcasting an earthquake warning. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is in the field of anti-backlash nut assemblies.
2. Description of the Prior Art
There are many applications in which it is important to drive an element in a machine along a screw which provides accurate positional repeatability and constant drag torque control. Data printers and x-y tables, used as peripheral equipment in the computer industry, for example, have such requirements.
Positioning devices designed to meet these requirements have been proposed, and many of these employ an anti-backlash nut assembly to achieve the positional accuracy along the screw which is required. Examples of two such anti-backlash nut assemblies which have been proposed are described in the patent literature as follows.
In U.S. Pat. No. 3,656,358, issued to Kopp, a linear positioning device is disclosed which is stated to have an improved collar for use with a comparatively inexpensive rod having multiple grooves. The collar is telescoped over and adapted to be translated back and forth relative to the elongated rod. This collar includes cantilevered fingers which are resiliently wedged into angularly spaced grooves formed in the rod to preload the collar onto the rod and prevent rotational play from developing between the two. In one specific embodiment, the collar is telescoped onto a rod in the form of a splined shaft while in another embodiment, the collar is a nut threaded onto a screw with multiple threads.
In U.S. Pat. No. 3,977,269, issued to Linley, an anti-backlash, self-aligning nut construction with specially constructed tubular nut bodies which coact with concentric spring sleeves is described. The nut bodies, in general, each have a pair of spring-biased elements provided with internal thread formations adapted for engagement with the external threads of a screw. In one embodiment, a self-aligning spring sleeve is provided having solely three pairs of oppositely-disposed transverse slots to obtain the desired aligning features. The nut body has a base portion which is separated from the spring-biased elements by means of two transverse slots which, together with an adjacent pair of slots in the spring sleeve, form in effect a universal joint. One of the remaining slot pairs in the sleeve is oriented circumferentially with respect to the first pair by an angle of 90°, with the third pair of slots being circumferentially aligned with the first pair.
Despite such prior proposals, none of the anti-backlash nut assemblies heretofore proposed has been entirely satisfactory. There is still a need for an anti-backlash nut assembly which is effective to assure positional repeatability and constant drag torque control, but is also easily and inexpensively manufactured.
SUMMARY OF THE INVENTION
This invention related to a new anti-backlash nut assembly designed to undergo translational movement along a threaded screw in response to relative rotational movement between the two. A unique feature of this anti-backlash nut assembly is that it contains a nut which is axially split into a first portion and a second portion. Both the first portion and the second portion of the axially-split nut are joined together to form the complete nut, which is then capable of translational movement along the screw. Means for retaining the first and second portions around the screw are provided, and one such means comprises a hollow cylindrical spacer.
Means to bias the first and second portions in opposite longitudinal directions along the screw are also provided. A suitable means for biasing is an open-wound helical spring which forces the two axially-split portions in opposite longitudinal directions.
In a preferred embodiment, the first and second axially-split portions can be mated together to form a cylindrically shaped nut with a hollow bore for the screw. The first portion of the nut is integrally connected to a tubular section having a larger outside diameter than the nut so that its face provides a shoulder for restraining one end of a helical spring used to bias the respective portions of the nut in opposite longitudinal directions. A faceplate for mounting an element of a machine to be driven along the screw is also integrally connected to the tubular section. The second portion of the axially-split nut has a section of enlarged outside diameter to provide a shoulder for restraining the other end of the helical spring.
The anti-backlash nut assembly of this invention has been found to offer outstanding advantages. A very significant advantage, for example, is the constant drag torque provided over the life of the unit irrespective of thread wear. Constant drag torque is established since the torque is directly proportional to the sum of the frictional forces retarding the turning motion of the screw when subjected to torque loadings. The longitudinally split-nut configuration allows for radial inconsistencies, and thus minimizes frictional forces produced by screw diameter variations. Total frictional forces are thus produced solely by the compression spring preload. Because the spring force is constant throughout nut travel and life of the unit, drag torque remains constant.
The compression spring preload also forces the nut body against the screw thread flanks and thus eliminates backlash.
Additionally, the axially-split nut can be manufactured more easily and inexpensively than most other anti-backlash nut assemblies. This is because it is longitudinally split which enables a "drop-out" injection molding process to be used instead of the normal "screw-out" process required for previously molded one-piece nut assemblies.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating an anti-backlash nut assembly according to this invention;
FIG. 2 is a side elevation view illustrating an anti-backlash nut assembly of this invention;
FIG. 3 is a side elevation view of the disassembled components of an anti-backlash nut assembly of this invention;
FIG. 4 is a cross-sectional view through an axially-split nut assembly of this invention;
FIG. 5 is a partially cut-away side elevation view showing an alternative embodiment of an anti-backlash nut assembly according to this invention which embodiment has radial flexures therein; and,
FIG. 6 is a cut-away diagram illustrating removal of a screw used to internally thread a nut in a prior art molding operation; and,
FIG. 7 is a cut-away diagram illustrating a drop-out molding process for producing both portions of an axially-split nut according to this invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
This invention can be further described by referring to the Figures in more detail.
In FIGS. 1-4, one embodiment of an anti-backlash nut assembly is illustrated as having a screw 10 and a nut assembly 12. The unique construction of nut assembly 12 can be seen clearly in FIGS. 2 and 3. Therein, a first integral section is illustrated as having first portion 14 of an axially-split nut, tubular section 16 having an enlarged outside diameter and a through-hole for screw 10, and faceplate 18 which also has a through-hole. As can be seen, the first portion 14 of the axially-split nut forms approximately one-half of a cylindrical nut having internal threads complementary to the external threads on screw 10. The second half of the complete cylindrical axially-split nut is provided by second portion 20 which has a raised shoulder formed by a section 22 with an increased outside diameter but also having a through hole.
First portion 14 and second portion 20 are retained in an aligned position about screw 10 by cylindrical, hollow spacer 24. Open wound helical spring coil 26 is placed around the outside of spacer 24 and has one end abutting the edge of tubular section 16 and its other end abutting the raised shoulder of section 22. Thus, spring 26 forces the first portion 14 and second portion 20 of the axially-split nut in opposite longitudinal directions to insure good contact with the flanks of the thread on screw 10.
The various components of the axially-split anti-backlash nut assembly can be fabricated from a variety of materials. The first and second portions of the nut could, for example, be fabricated from metals such as steel or cast bronze, or from any thermoplastic moldable polymer composition. It is preferred to mold components which contact the screw from low-friction, self-lubricating polymer compositions which have outstanding wear characteristics. Other components could be similarly made from metal or plastics.
FIG. 5 illustrates an alternative embodiment of an axially-split anti-backlash nut assembly according to this invention. In this embodiment, components similar to those previously described have been given numerals corresponding to those previously used. Thus, there is an externally threaded screw 10 and an anti-backlash nut assembly 12. Anti-backlash nut assembly 12 is formed from an axially-split nut having first and second portions similar to those previously described but not shown in FIG. 5. Additionally, the axially-split nut is retained in contact with screw 10 by hollow cylindrical spacer 24 and a helical spring 26 is used to bias the first and second portions in opposite longitudinal directions. This assembly additionally includes, however, a free floating faceplate 28 which is joined to the nut by radial flexures such as flexures 30 and 32. It is preferred to join faceplate 28 to the nut by three radial flexures to provide good structural integrity. Radial flexures 30 and 32 extend from faceplate 28 through outer cylindrical housing 34 to the far end of the nut where they are fastened to an aluminum plate 36 which is in turn joined to plastic end piece 38 which is molded integrally with a portion of the axially-split nut. Of course, plate 36 and end piece 38 could be fabricated from other materials. Also, other means for fastening the flextures 30 and 32 onto the nut could be used. Flexures 30 and 32 could be formed from many different materials, with spring steel being preferred. These flexures serve to allow faceplate 28 to be somewhat free floating to compensate for misalignment between screw 10 and the mounting shafts for a device being driven along screw 10 by the nut assembly 12. Thus, potential binding problems are eliminated.
FIG. 6 illustrates the withdrawal of a threaded mold insert 40 which has been used in injection mold 42 in a typical injection molding cycle for prior art nuts. Insert 40 has a threaded tip 44 which is screwed into tap 46 to hold insert 40 in mold 42 during the injection molding process. Insert 40 serves to form internal threads on nut 46 which is formed during the molding operation. As illustrated, threaded mold insert 40 is removed after nut 48 has been formed by rotating it in the counterclockwise direction. While this procedure is effective, it has the disadvantage of requiring a relatively time-consuming step of removing threaded mold insert 40 after the rest of the molding cycle has been completed. Often, this is done by hand which not only is time consuming but also adds inordinately to the cost of manufacturing the nut.
FIG. 7 illustrates a molding process which can be used to manufacture axially split nuts according to this invention. This process is often referred to as a drop-out injection molding process and it eliminates the requirement for removal of a threaded mold insert after the cycle is complete.
In the drop-out injection molding process, a two part mold consisting of upper mold section 50 and lower mold section 52 is used. A mold insert 54 is provided to mold an appropriate thread onto the inside of the nut. Threaded mold insert 54 can be separate from upper mold section 50, in which case it is inserted prior to the molding cycle, or it can be formed as an integral part of upper mold section 50. Mold insert 54 is also provided with a small extension 56 which serves to separate the first portion 58 from second portion 60 of the axially-split nut being molded. After the nut has been molded, upper mold section 50 is separated from lower mold section 52 to release first portion 58 and second portion 60 of the axially-split nut. Thus, the requirement to subsequently remove a threaded insert by manually or otherwise back-screwing the insert is eliminated.
Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific components, elements, steps, materials, etc., described herein. It is possible, for example, to have more than two axially-split portions for the nut assembly, although this is usually not preferred. Such equivalents are intended to be covered by the following appended claims. | An anti-backlash nut assembly is disclosed of the type which undergoes translational movement along a screw in response to relative rotational movement between the nut and screw. The assembly includes a nut which is axially-split into first and second portions, both of which have an internal thread complementary to the external thread of the screw. The two portions of the axially-split nut are retained in the radial direction by a spacer, and a spring is used to apply biasing in the longitudinal direction to minimize backlash. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/272,118 filed Aug. 18, 2009, the entire contents of which is herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to processes for preparing polymeric compositions. In particular, the present invention relates to blends of polymer and thermoplastic starch and processes for producing such blends.
BACKGROUND OF THE INVENTION
[0003] Thermoplastic starch is produced by mixing native starch with a plasticizer at a temperature above the starch gelatinization temperature, typically in the 70-90° C. range. This operation weakens the hydrogen-bonds present in the native starch leading to a fully amorphous free-flowing material. The resulting material is known as plasticized starch, destructured starch or thermoplastic starch (TPS). The properties and rheology of thermoplastic starch have been thoroughly investigated (Aichholzer 1998; Vergnes 1987; Villar 1995; Willett 1995). As such, the TPS is not a suitable material for most common uses. It is very hygroscopic and its properties and dimensional stability are strongly affected by the humidity level since water is a plasticizer for TPS. Also in presence of humidity, the amorphous TPS tends to reform its hydrogen-bonds leading to recrystallization (also called retrogradation) and in turn to embrittlement of the material.
[0004] This strong property dependence on plasticizer content can become an advantage however when the TPS is blended with another hydrophobic polymer. In this case, the hydrophobic polymer can protect the TPS from direct water contact and moisture uptake while the plasticizer level in the TPS can be used to tune the mechanical properties of the TPS. Therefore, the vast majority of work involving the use of starch as a material has focused on blending of TPS and other synthetic polymers (Averous 2004; Schwach 2004; Wang 2003). The synthetic material can be biodegradable to produce a fully compostable material or can be non-biodegradable to produce materials for longer-term applications. Examples of biodegradable blends include blends of TPS with polycaprolactone or polybutylene succinate which are two petrochemical based polymers. With the recent commercial introduction of poly(lactic acid) PLA, there has also been a high interest for PLA/TPS blends and these have been investigated in terms of their compatibility (Huneault 2007) and of their processing into injection molded product, biaxially oriented films (Chapleau 2007) and low density foams (Mihai 2007).
[0005] The compounding process used for the preparation of TPS/polymer blends is relatively complex. It must nominally enable the precise metering of starch and plasticizers, the starch gelatinization and the mixing of the TPS with the second polymer phase to obtain finely dispersed or finely segregated blend morphology. Additionally, more elaborate functions may be performed. For example, venting or devolatilization may be used to control volatiles levels. Interface modification through in situ interfacial reaction may be used to compatibilize the blend or to modify the starch interface. Surprisingly, very little scientific publications have focused on the effect of the process on the final blend properties and little guidance can be found as to what could be the best practices in terms of TPS/polymer blend compounding technology.
[0006] In order to prepare finely dispersed blends of thermoplastic starch and synthetic polymers, it is beneficial to prepare the blends using a sequence of operation carried out along a twin-screw extrusion process (Favis 2003; Favis 2005; Favis 2008; Rodriguez-Gonzalez 2003). In the process described in the Favis et al. patents (Favis 2003; Favis 2005; Favis 2008; Rodriguez-Gonzalez 2003), the basic ingredients for the making of thermoplastic starch, starch, water and glycerol, are first mixed in 50:25:25 proportions to form a suspension (also referenced as a slurry). This suspension is pumped into the extruder. Under the action of shear and heat, the starch and plasticizers (water and glycerol) are transformed into thermoplastic starch (TPS) through a well known transformation called “gelatinization”. Further along the extrusion process, the water is removed to get a water-free TPS that is solely plasticized by glycerol. Then, further along the process, a synthetic polymer is added and mixed with the TPS to form the TPS/polymer mixture that is the end result of the process. In the Favis et al. process, it is specified that the synthetic polymer must be added in molten form to prepare blends with an acceptable dispersion.
[0007] There are at least two problems with the process presented in the prior art described above. First the use of a suspension forces the use of a high initial water content because starch suspensions necessitate at least 50% liquid to be pumped into the extruder. Since a water-free TPS is desired, this involves a very high rate of devolatilization and in turn a lower production rate and higher energy need. According to the Favis et al. patents cited above however, this water is necessary to achieve proper TPS gelatinization. The second problem with the Favis et al. process is that the synthetic polymer must be fed to the twin-screw process in liquid form. Thus a single-screw extruder must be used to heat, melt and pump the polymer into the extruder. Favis 2005 and Favis 2008 teach that feeding in liquid (molten) form is necessary for the formation of finely dispersed blends and in turn to good retention of material ductility. Feeding a polymer in molten form requires an auxiliary unit such as a single-screw extruder that is able to heat and pump the polymer at high pressure and thus requires additional energy, involves additional cost in comparison to feeding the polymer at room temperature.
[0008] In another report (Seidenstucker 1999), thermoplastic poly(ester-urethanes) (TPU) were compounded with destructurized starch in a twin-screw extruder. This report describes two-step processes similar to Favis et al. in which thermoplastic starch (TPS) is first made by pre-mixing starch with a polyfunctional alcohol before introduction into the twin-screw extruder. This report also describes a single-step process in which starch is introduced into the twin-screw extruder followed by introduction of glycerol downstream to form the thermoplastic starch in the extruder, and then followed by introduction of TPU further downstream in the extruder. This report indicates that the throughput of the single-step process is reduced to one-third of the two-step processes. Only two-step processes are actually used to produce TPS/polymer blends in this report, and there is no description of how much or even whether water can be used in conjunction with the glycerol for forming the thermoplastic starch in the single-step process.
[0009] In yet another report (Wiedman 1991), a twin-screw extrusion sequence is described for a food processing extrusion line involving thermoplastic starch. In this case steam injection and an unspecified liquid feed are used. There is no description of any particular plasticizer composition involving polyfunctional alcohols and water and no description of any control over the ratio of water to polyfunctional alcohol in the plasticizer. Even if the unspecified liquid feed did contain polyfunctional alcohol, controlling the water:polyfunctional alcohol ratio would be very difficult using the steam injection process. Further, to introduce polymer into the line, either a feeder located at the same point as the starch feeder or a downstream twin-screw side feeder could be used. If the feeder is used to introduce dry polymer, the polymer would be added at the same point in the line as the starch. If the downstream twin-screw side feeder is used, the polymer would be introduced in liquid form.
[0010] There remains a need in the art for an efficient process of making thermoplastic starch/polymer blends.
SUMMARY OF THE INVENTION
[0011] It has now been found that separately introducing dry starch and liquid plasticizer as input for a thermoplastic starch (TPS) phase and solid room temperature incorporation of a polymer phase in a twin-screw operation sequence overcomes one or more of the problems associated with prior art processes.
[0012] There is provided a process of producing a thermoplastic starch/polymer blend comprising: introducing dry starch into a twin-screw extruder at a first location along the extruder; introducing a plasticizer into the twin-screw extruder at a second location along the extruder downstream of the first location to form a starch paste and then gelatinizing the starch paste in the extruder to form thermoplastic starch; and, introducing dry polymer at ambient temperature into the twin-screw extruder at a third location along the extruder downstream of the second location to form a blend with the thermoplastic starch in the extruder.
[0013] The dry starch can be any suitable starch that can be converted to thermoplastic starch. For example, starch obtained from corn, wheat, triticale, peas, potatoes, rice, cassava and sorghum, as well as chemically modified starches (e.g. acetylated starch, hydroxypropylated starch, phosphorylated starch) can be converted into TPS. The starch is introduced into the twin-screw extruder in dry form, for example, as pellets, granules, powders and the like, by any suitable means, for example feeders.
[0014] The plasticizer comprises a functionalized compound, for example a polyfunctional alcohol or an amide functionalized compound. The polyfunctional alcohol may be, for example glycerol, sorbitol, polyethylene glycol or mixtures thereof. The amide functionalized compound may be, for example, urea, formamide, ethylene-bisformamide or mixtures thereof. The plasticizer preferably comprises glycerol and/or sorbitol.
[0015] Starch-slurry processes as described in the prior art (e.g. Favis 2003; Favis 2005; Favis 2008; Rodriguez-Gonzalez 2003) typically have a water:glycerol ratio of about 1:1 w/w. Lower amounts of water in the plasticizer facilitates the formation of a starch paste rather than a slurry. Thus, the plasticizer preferably does not comprise water or comprises water and the functionalized compound in a ratio in a range of from 0.01:10 to 5:10 w/w water:functionalized compound. The ratio of water:functionalized compound is preferably in a range of from 0.5:10 to 2:10 w/w, for example 1:10 w/w.
[0016] The plasticizer is introduced into the extruder in an amount related to the amount of starch introduced. Preferably, the plasticizer is used in an amount to provide the functionalized compound in a range of from 20 wt % to 40 wt % based on the weight of water-free thermoplastic starch phase, more preferably in a range of from 24 wt % to 36 wt %. Preferably, the total amount of plasticizer used (water+functionalized compound) is 40 wt % or less based on the weight of starch used, more preferably in a range of from 5 wt % to 40 wt %. Liquid plasticizer may be introduced into the extruder by any suitable means, for example by use of a feed line and a pump. Solid plasticizer can be fed using a gravimetric or volumetric feeder. Water may be removed from the thermoplastic starch by one or more volatilization steps in the extruder.
[0017] The formation of a starch paste between the dry starch and the plasticizer is an important and advantageous distinction of the present process over slurry processes such as the one disclosed by Favis et al. In slurry processes, sedimentation due to gravity can create problems with blend consistency. In the present process, the paste comprises solid particulates contacting each other with the liquid acting as a lubricant, thus, sedimentation is not a significant issue.
[0018] The polymer may comprise any suitable polymer for blending with thermoplastic starch. The particular polymer is generally dictated by the end use of the TPS/polymer blend. Polymers comprising polyethylene, polypropylene, polystyrene, poly(lactic acid), poly(ε-caprolactone), polybutylene succinate, copolymers thereof or mixtures thereof are specific examples of polymers for which the process of the present invention is particularly suited. The polymer may be introduced into the extruder in an amount to provide TPS/polymer blends having an amount of TPS in a range of from 5 wt % to 95 wt % based on the weight of the blend, more preferably in a range of from 10 wt % to 90 wt %. The polymer is introduced into the twin-screw extruder in dry form, for example, as pellets, granules, powders and the like, by any suitable means, for example feeders.
[0019] The polymer may be compatibilized with the starch using a compatibilzer. Preferred compatibilizers are random or graft copolymers where the main monomer is of similar nature as the polymer to be compatibilized and where the grafted or randomly copolymerized co-monomer is capable of reacting with available hydroxyl moieties of starch. The reactive co-monomers may be unsaturated carboxylic acids, unsaturated carboxylic acid anhydrides, esters of acrylic acid or mixtures thereof, more preferably unsaturated carboxylic acid anhydrides. Some suitable unsaturated carboxylic acids include, for example, acrylic acid, maleic acid, tetrahydrophthalic acid, fumaric acid, itaconic acid, nadic acid, and methylnadic acid. Some suitable anhydrides include, for example, maleic anhydride, tetrahydrophthalic anhydride, fumaric anhydride, itaconic anhydride, nadic anhydride, and methylnadic anhydride. Maleic anhydride is of particular note. A suitable ester of acrylic acid may be, for example, glycidyl methacrylate. Grafting level in grafted polymers is preferably from 0.2 wt % to 5 wt % based on total weight, more preferably from 0.5 wt % to 2 wt %. For copolymers, the reactive monomer content is preferably from 1 wt % to 20 wt %, preferably from 5 wt % to 10 wt %. Preferably, the compatibilization is accomplished by partially substituting the base polymer with the compatibilizer. From 2 wt % to 25 wt % of the polymer is substituted with the compatibilizer, more preferably from 5 wt % to 15 wt %.
[0020] Flow rates for introducing the various components into the twin-screw extruder may be set to achieve the proportions outlined above. Process temperatures may be any suitable temperature used in the art for thermoplastic starch/polymer blending, for example as disclosed by Favis et al. (Favis 2003; Favis 2005; Favis 2008; Rodriguez-Gonzalez 2003) with the advantage that polymer may be fed into the extruder in dry form at ambient temperature. In one embodiment of the process, dry starch is introduced into the twin-screw extruder at a rate of 7 kg/hr, polyfunctional alcohol is introduced at a rate of 3 kg/hr, water is introduced at a rate of 0.3 kg/hr and polymer is introduced at a rate of 3 kg/hr, with a TPS/polymer blend output of 13 kg/hr and a water removal rate of 0.3 kg/hr.
[0021] The process of the present invention may also include other steps useful for producing usable thermoplastic starch/polymer blends. For example, water from the thermoplastic starch may be removed before the introduction of dry polymer. Water removal may be accomplished by any suitable means, for example, by using a vent under atmospheric pressure or under vacuum. Further, the thermoplastic starch/polymer blend may be extruded through an extrusion die to directly form a final product or formed into an extrudate that will be pelletized prior to further processing using conventional polymer processing machinery.
[0022] Advantageously, the process of the present invention requires the use of less water in the plasticizer than two-step processes such as the one disclosed by Favis et al. resulting in lower energy requirements and higher production rate. Because of the lower water usage, lower residual water levels in the TPS can be obtained. This is an advantage when blending the TPS with water-sensitive biopolymers such as polylactides and polyhydroxyalcanoates. Further, the process does not require feeding molten polymer into the extruder line thereby lowering energy demand and reducing cost.
[0023] Further features of the invention will be described or will become apparent in the course of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In order that the invention may be more clearly understood, embodiments thereof will now be described in detail by way of example, with reference to the accompanying drawings, in which:
[0025] FIG. 1 depicts a twin-screw extrusion configuration for a dry-starch process of the present invention;
[0026] FIG. 2 depicts X-ray diffraction patters showing intensity of starch and thermoplastic starch (TPS) produced using different plasticizer addition methods;
[0027] FIG. 3 depicts SEM micrographs of uncompatibilized 25% TPS/polymer blends produced with the starch-slurry process of the prior art (left) and the dry-starch process of the present invention (right);
[0028] FIG. 4 depicts SEM micrographs on 25% TPS/polymer blend compatibilized with maleic anhydride-containing copolymers produced with the starch-slurry process of the prior art (left) and the dry-starch process of the present invention (right);
[0029] FIG. 5 depicts SEM micrographs showing effect of different sorbitol/glycerol ratio on 27% TPS/PLA blend morphology, for unmodified PLA (left) and PLA-g-MAh (right); and,
[0030] FIG. 6 depicts a graph showing effect of sorbitol/glycerol ratio on tensile strength and modulus of TPS/PLA blends.
DESCRIPTION OF PREFERRED EMBODIMENTS
Example 1
Comparison of Starch-Slurry and Dry-Starch Processes
Materials
[0031] Wheat starch was used as the sole starch source. The starch was an industrial purpose starch grade, Supergel™ 1201, supplied by ADM. The grade names and suppliers of PE, PP, PS, PCL and PLA are summarized in Table 1. The blend composition was set to 25% TPS for all TPS/polymer blends. For compatibilization of the TPS/polymer blends, functional polymers containing maleic anhydride were used to react with the starch macromolecules to create graft block copolymers that are known to act as emulsifiers in polymer blends. In the case of PE and PP, the functional version were maleic anhydride grafted PE and PP. For blends of TPS with PS, a random copolymer of styrene and maleic anhydride, SMA. For PLA, no such MAh grafted version was commercially available. Thus PLA-g-MAh was produced by extruding PLA in presence of 2% maleic anhydride and 0.25% organic peroxide. For PE, PP and PS, 10% of the polymer was substituted by the maleated analogs. For PLA, 20% substitution was used.
[0000]
TABLE 1
List of Polymers
Name
Abbrev.
Grade/Supplier
High-density polyethylene
PE
DMDA8920, Petromont
Polypropylene copolymer
PP
Profax SB821, Basell
Polystyrene
PS
PS 3500, Nova Chemicals
Polycaprolactone
PCL
Tone 787, Dow Chemicals
Poly(lactic acid)
PLA
PLA 4032D, Nature Works
MAh grafted PE
PE-g-MAh
Polybond 3009
MAh grafted PP
PP-g-MAh
Polybond 3150
MAh grafted PLA
PLA-g-MAh
Experimental
Styrene-MAh copolymer
SMA
Dylark 232, Nova Chemicals
Blend Preparation
[0032] Two material incorporation processes were compared. A prior art process (Favis 2003; Favis 2005; Favis 2008; Rodriguez-Gonzalez 2003), referred to as the “starch-slurry process”, was compared to a process of the present invention, referred to as the “dry-starch process”.
[0033] The starch-slurry process comprises premixing the plasticizer and the starch in presence of an excess of water to form a slurry that can easily be pumped into the primary feed-port. This process was first reported by Rodriguez-Gonzalez et al. (Rodriguez-Gonzalez 2003) and was later used in a number of works focused on polyethylene/TPS blends. It was assumed that the excess water in the suspension accelerates the gelatinization process. It must be removed at mid-extruder using vacuum devolatilization to provide a water-free TPS before mixing in the second polymer phase. The second polymer phase was added in molten form using a single-screw extruder as a side-feeder. In the present comparative examples, the polymers were fed in the form of regular solid pellets using a regular side feeder.
[0034] Surprisingly, it has now been found experimentally for selected blends that similar blend morphologies could be achieved with melt and solid polymer side-feeding.
[0035] In the dry-starch process of the present invention, TPS/polymer blends were prepared on a Leistritz 34 mm co-rotating twin-screw extruder with an L/D ratio of 42. The process and screw configuration for TPS/polymer blending are presented in FIG. 1 . Barrel sections 0 to 3 were used to gelatinized the starch. Sections 4 to 6 were used for the devolatilization under vacuum. This first half of the extrusion process was typically operated at T gel =140° C. but for selected experiments it was decreased down to 85° C. to investigate the effect of temperature on the starch gelatinization. Sections 7 to 11 were used to thoroughly mix the TPS with the second polymer phase. This mixing step was carried out at 180° C. in all cases. All blend compounding runs were carried out at a rate of 10 kg/hr and extruded through a 2-strand die. The strands were air-cooled and pelletized. The PLA was dried prior to compounding and the compounded pellets were dried again in a desiccating dryer at 55° C. prior to injection molding.
[0036] The dry-starch process comprises feeding the starch in dry-form at the primary feed-port and pumping the plasticizers further down along the extrusion line in barrel section 1 as shown in FIG. 1 . This process enables plasticizer incorporation and gelatinization to be carried out in a single continuous operation without any need for pre-mixing. The second polymer phase is added at mid-extruder in pellet form. As with the starch-slurry process, excess water is pumped along with the glycerol and later devolatilized. For the dry starch process, a 1:10 w/w water:glycerol ratio was used as a standard condition but this ratio was varied in specific experiments to assess the effect of water on the TPS gelatinization. In this case however, the water and glycerol input concentrations were independent and not limited by any practical slurry pumping concerns.
Gelatinization
[0037] X-ray diffraction was used to detect changes in the crystalline and ordered structures of starch upon processing and as a way to insure that complete gelatinization was achieved at the end of the compounding process. Wide-angle X-ray diffraction measurements were carried out directly on the pure TPS bands. The diffraction patterns were obtained with a D-8 X-Ray Diffractometer (Bruker). The samples were exposed to X-ray beam with the X-ray generators running at 40 Kv, and 40 mA. The scanning was carried out at a rate of 0.03 o/s in the angular region ( 2 θ) of 2-40°.
[0038] In FIG. 2 , the diffraction intensity was compared for native and thermoplastic starch obtained with starch-slurry and dry-starch processes operated at 140° C. Also presented in the figure is dry-starch previously soaked with the plasticizers and extruded into TPS, which is another prior art process for making TPS. The peaks observed around 15, 18 and 23° for the native wheat starch correspond to those expected from the A-type crystalline structures. These peaks have totally disappeared in all gelatinized starches regardless of the preparation technique. Sharp new peaks at 13.5° and 21° and a broader one around 19° have appeared for the gelatinized starches indicative of the V-type structure. Thus, regardless of the process, the gelatinization was completed at the point where the TPS is mixed with the second polymer at mid-extruder.
Dispersion
[0039] The blend morphology was assessed by observation of microtomed surfaces using scanning electron microscopy (SEM). The surfaces were prepared using an ultramicrotome at −100° C. using a diamond knife. The surfaces were subsequently treated with hydrochloric acid (HCl, 6 N) for 3 hr to selectively extract the TPS phase.
[0040] The most important measure of mixing quality in a polymer blend is usually the size of the dispersed phase. FIG. 3 presents SEM micrographs of uncompatibilized blends obtained with the starch-slurry (left) and dry-starch (right) processes. The TPS was selectively removed prior to SEM observation to enhance contrast. The compositions were similar in all cases with 27 wt % TPS in the different continuous phases. The TPS phase comprised 36 wt % glycerol on a water-free TPS basis. For the starch-slurry process, a 1:1 water:glycerol ratio was used in the slurry. A 1:10 water:glycerol ratio was selected for the dry-starch process. Since water is removed to a great extent in the devolatilization zone of the extrusion process, similar final blend compositions were obtained at the end of the two process variants. The TPS dispersion was coarsest in PE and PP as expected from the non-polar nature of polyolefins. The dispersed phase size obtained with the starch-slurry and dry-starch processes were similar. The TPS particle diameter in PE ranged between 5 and 15 μm. In PP, the TPS phases were larger, in excess of 50 μm, and with irregular shapes. Obviously, the dispersed phase was capable of coalescing since the final TPS domain size largely exceeded the initial native starch particle dimension (ca. 15-25 μm). In PS and PLA, the TPS particle dimensions were slightly smaller and the particles exhibited more irregular shapes as if they were still in the process of being deformed under flow. Again, no significant morphological differences were observed when comparing the two compounding processes. The last investigated blend was TPS/PCL. PCL is known to be more compatible with TPS due to its more polar nature. For both processes, the morphology was much finer with particle sizes on the micrometer level.
[0041] FIG. 4 presents SEM micrographs for the same blends as in FIG. 3 but in this case in presence of their respective compatibilizing agents described in the Table 1. The compatibilizing agents used are all modified version of the continuous phase polymer containing various amount of maleic anhydride. The maleic anhydride moieties increase the polarity of the polymer and can potentially react with hydroxyl groups present on the starch macromolecules. This reaction necessarily occurs at the blend interface and thus forms in situ graft copolymers that act as an emulsifier in the blend. When comparing FIGS. 3 and 4 , it is clear that all the maleated compatibilizers used successfully reduced the dispersed phase size. In the PE and PS matrices, the TPS particle size was lowered to the 1-2 μm range. For TPS/PP, the particle size was not decreased to the micron level but were still significantly reduced compared to the morphology of the uncompatibilized blends. For the compatibilized TPS/PLA blends, slightly finer morphologies were obtained with the dry-starch process.
Tensile Properties
[0042] Table 2 presents the tensile properties of the blends containing 25% TPS in the various investigated polymer matrices. The properties of the pure matrices are given as reference. In the case of PE and PP based blends, the modulus and strength of the blends were similar to that of the PE and PP matrices but the elongation was severely decreased. For the noncompatibilized TPS/PE blends, the elongation obtained with the dry-starch process was significantly higher compared to the starch-slurry process. The effect was even more pronounced in the compatibilized TPS/PE and TPS/PP cases. In fact, for the PE based blend, the samples were able to extend up to the maximum extension of the tensile testing equipment (i.e. 800%). PS and PLA were more rigid matrices. The addition of TPS therefore decreased the modulus and strength in a more significant way but left nearly unchanged the already low elongation at break of the matrices. The TPS and PCL are known to be more compatible without the use of an interfacial modifier. The tensile modulus and strength were decreased with addition of the TPS phase but the elongation at break remained in excess of 800%. In view of these findings, it seems that relatively similar tensile properties can be achieved with the starch-slurry and dry-starch processes, except that the dry-starch process can provide significant improvement in elongation properties. The dry-starch process has an advantage in blends with water-sensitive materials because of the lower achievable TPS moisture content.
[0000]
TABLE 2
Tensile Properties of Polymers and Polymer Blends
Tensile
Elongation
Modulus
Strength
at break
Polymer
Process
(GPa)
(MPa)
(%)
PE
1.12
17.9
>800
TPS/PE
Starch-slurry
1.41
16.0
133
Dry-starch
1.05
15.8
233
TPS/PE-g-MAh
Starch-slurry
1.14
18.7
27
Dry-starch
0.935
16.0
>800
PP
1.00
18.8
700
TPS/PP
Starch-slurry
1.06
16.8
19
Dry-starch
0.914
16.4
12
TPS/PP-g-MAh
Starch-slurry
1.16
19.85
15
Dry-starch
0.989
18.0
44
PS
3.28
37.0
2.0
TPS/PS
Starch-slurry
3.09
34.1
1.9
Dry-starch
2.97
31.0
2.1
TPS/SMA
Starch-slurry
3.13
31.5
1.4
Dry-starch
2.87
31.9
2.0
PLA
3.68
69.2
6.0
TPA/PLA
Starch-slurry
3.20
49.0
4.9
Dry-starch
3.33
46.6
4.0
TPS/PLA-g-MAh
Starch-slurry
3.18
49.6
4.2
Dry-starch
2.96
45.8
6.8
PCL
0.43
25
>800
TPS/PCL
Starch-slurry
0.339
12.3
>800
Dry-starch
0.259
11.0
>800
[0043] Two starch/plasticizer incorporation schemes referred to as the starch-slurry (prior art) and dry-starch methods (present invention) were compared using a water:glycerol plasticizer. Complete gelatinization was obtained regardless of the process when the starch was gelatinized at temperatures in excess of 85° C. Very similar blend morphologies and blend mechanical properties were obtained using the slurry and dry starch processes and these two methods enabled fabrication of TPS with high plasticizer contents. The dry-starch method of the present invention in which the starch and plasticizer were fed sequentially in the extruder was shown to be most flexible since it enabled the use of any desired plasticizer and initial water level and does not require any premixing step. The starch-slurry method enabled the use of high glycerol fraction compared to the amount of starch, but at the same time required the use of a high initial water fraction to maintain sufficient slurry fluidity. This increased initial water usage in the starch-slurry process of the prior art increases the required devolatilization rates and required process energy without benefit in terms of blend properties.
Example 2
Comparison of Glycerol- to Sorbitol-Based Plasticizer in Dry-Starch Process
[0044] This example investigates the morphology and properties of TPS/PLA blends prepared using the dry-starch process of the present invention, with TPS plasticized by sorbitol, glycerol and glycerol/sorbitol mixtures.
Materials
[0045] Poly(lactic acid), supplied by Nature Works, was a semi-crystalline grade (PLA 4032D) comprising around 2% D-LA. Wheat starch, Supergel™ 1203, was provided by ADM-Ogilvy. D-Sorbitol was obtained from Aldrich Chemical Company with a purity of 98%. The glycerol was a 99.5% pure USP grade supplied by Mat Laboratories. The reactive modification of PLA was performed using maleic anhydride (95% pure) and 0.25% of a peroxide initiator 2,5-dimethyl-2,5-di-(tertbutylperoxy) hexane (Luperox™ 101 or L101) obtained from Aldrich Chemical Company. The maleic anhydride grafted PLA was prepared according to the method described in an earlier work (Huneault 2007).
Blend Preparation
[0046] PLA/TPS blends were prepared on a Leistritz 34 mm co-rotating twin-screw extruder with an L/D ratio of 42. The process and screw configuration are presented in FIG. 1 . The dry-starch and sorbitol were dry-blended and were supplied to the primary feed hopper using a gravimetric feeder. The glycerol was pumped into the extruder in the subsequent barrel zone. Water was added with glycerol to accelerate the starch gelatinization process but was removed by vent and vacuum devolatilization in barrel zones 4 and 5 . The PLA was added in pellet form using a side-feeder to the water-free gelatinized starch at barrel zone 7 and then mixed in the subsequent kneading section of the extruder. When maleic anhydride grafted PLA (PLA-g-MAh) was used to compatibilize the blend, it was dry-blended with PLA prior to extrusion. In that case, 20% PLA was substituted by PLA-g-MAh. The sorbitol/glycerol ratio was varied from 0:36, 12:24, 24:12, 36:0, maintaining a total plasticizer content of 36 wt % in TPS phase. The extruder temperature was set to 140° C. in barrel zone 1 to 6 dedicated to starch gelatinization and water removal. In the second extruder portion dedicated to PLA/TPS mixing, the extruder temperature was set to 180° C. The mixtures were extruded at a rate of 10 kg/hr through a 2-strand die. TPS content was kept at 27 wt %. The strands were water-cooled and pelletized. The PLA was dried prior to compounding and the compounded pellets were dried again in a desiccating dryer at 60° C. prior to injection molding and to subsequent analysis.
Blend Morphology
[0047] Blend morphology was assessed by observation of microtomed surfaces using scanning electron microscopy (SEM). Microtoming was carried out at room temperature using a diamond knife and the surfaces were subsequently treated with hydrochloric acid (HCl, 6 N) for 3 hr to selectively dissolve the TPS phase.
[0048] The morphology of 27% TPS/PLA blends for different glycerol/sorbitol ratios is presented in FIG. 5 . A very coarse morphology with particles ranging from 5 μm to 30 μm was obtained for non-compatibilized (unmodified) glycerol plasticized blends. Surprisingly, as the glycerol was substituted by increasing levels of sorbitol (panels a), c), e) and g)), the particle size progressively decreased to the 1-2 μm range and the particles became more spherical and homogeneously distributed.
[0049] The dispersed phase size reduction with the substitution of glycerol by sorbitol was unexpected. It is noteworthy that the blend morphologies reported here are much finer than those reported by Ke et al. (Ke 2001) for sorbitol-TPS/PLA blends. Ke et al. have investigated blends of PLA and up to 40 wt % TPS plasticized by adding 5-25 wt % sorbitol. Very coarse structure was obtained with the particles sizes around 20 μm. The main difference between this prior art result and the ones reported in the present disclosure comes from the compounding process. In their process the PLA, starch, and sorbitol were dry-mixed and fed together into a twin-screw extruder. This does not provide the proper incorporation of the plasticizer into the TPS phase and does not enable to complete starch gelatinization prior to TPS/PLA mixing.
Tensile Characterization
[0050] FIG. 6 shows the tensile strength and modulus for the uncompatibilized 27% TPS/PLA blends comprising different glycerol:sorbitol ratios. The tensile strength increased progressively from 47 MPa for glycerol plasticized blend, to 59 MPa for sorbitol (complete substitution) plasticized blend. The modulus also increased from around 3.3 GPa, for the glycerol plasticized blend to 3.5 GPa. The finer morphology observed with sorbitol therefore had clear benefits in terms of material rigidity and strength. In terms of ultimate properties, all materials exhibited low elongation at break, between 4% and 4.7%, as expected from the brittle nature of PLA.
[0051] It is also noteworthy that sorbitol, a solid particulate at room temperature, could not be incorporated using the prior art starch-slurry process without using an excessive initial water concentration to make the slurry flowable. In the present disclosure, the plasticizer input concentration is decoupled from the starch concentration since the ingredients are incorporated separately. Therefore, the advantageous properties obtained with the use of sorbitol/glycerol mixtures for starch plasticization could not be obtained without the concentration flexibility provided by the present invention.
REFERENCES
[0052] The contents of the entirety of each of which are incorporated by this reference.
Aichholzer W, Fritz H G. (1998) Rheological characterization of thermoplastic starch materials. Starch - Starke. 50: 77-83. Averous L. (2004) Biodegradable multiphase systems based on plasticized starch: a review. Journal of Macromolecular Science - Polymer Reviews. C 44: 231-274. Chapleau N, Huneault M A, Li H B. (2007) Biaxial Orientation of Polylactide/Thermoplastic Starch Blends. International Polymer Processing. 5: 402-409. Favis B D, Rodriguez F, Ramsay B A. (2003) Polymer Compositions Containing Thermoplastic Starch. U.S. Pat. No. 6,605,657 issued Aug. 12, 2003. Favis B D, Rodriguez F, Ramsay B A. (2005) Method of Making Polymer Compositions Containing Thermoplastic Starch. U.S. Pat. No. 6,844,380 issued Jan. 18, 2005. Favis B D, Rodriguez F, Ramsay B A. (2008) Polymer Compositions Containing Thermoplastic Starch and Process of Making. Canadian patent 2,395,260 issued Feb. 5, 2008. Huneault M, Mighri F, Ko G H, Watanabe F. (2001) Polymer Engineering & Science. 41: 672-683. Huneault M A, Li H B. (2007) Morphology and properties of compatibilized polylactide/thermoplastic starch blends. Polymer. 48: 270-280. Ke T, Sun X. (2001) Transaction of the American Society of Agricultural Engineers. 44: 945-953. Mihai M, Huneault M A, Favis B D, Li H B. (2007) Foaming of PLA/Thermoplastic Starch Blends. Macromolecular Bioscience. 7: 907-920 (2007). Rodriguez-Gonzalez F J, Ramsay B A, Favis B D. High performance LDPE/thermoplastic starch blends: a sustainable alternative to pure polyethylene. (2003) Polymer. 44(5): 1517-1526. Schwach E, Averous L. (2004) Starch-based biodegradable blends: morphology and interface properties. Polymer International. 53: 2115-2124. Seidenstucker T, Fritz H-G. Compounding Procedure, Processing Behaviour and Property Profiles of Polymeric Blends Based on Thermoplastic Poly(ester-urethanes) and Destructurized Starch. (1999) Starch - Starke. 51(2-3): 93-102. Vergnes B, Villemaire J P. (1987) Rheological behaviour of low moisture molten maize starch. Rheol Acta. 26: 570-576. Villar M A, Thomas E L, Armstrong R C. (1995) Rheological properties of thermoplastic starch and starch/poly (ethylene-co-vinyl alcohol) blends. Polymer. 36: 1869-1876. Wang X L, Yang K K, Wang Y Z. (2003) Properties of starch blends with biodegradable polymers. Journal of Macromolecular Science - Polymer Reviews. C 43: 385-409. Wiedmann W, Strobel E. (1991) Compounding of Thermoplastic Starch with Twin-screw Extruders. Starch - Starke. 43(4): 138-145. Willett J L, Jasberg B K, Swanson C L. (1995) Rheology of Thermoplastic Starch: Effect of Temperature, Moisture Content, and Additives on Melt Viscosity. Polymer Engineering and Science. 35(2): 202-210.
[0071] Other advantages that are inherent to the structure are obvious to one skilled in the art. The embodiments are described herein illustratively and are not meant to limit the scope of the invention as claimed. Variations of the foregoing embodiments will be evident to a person of ordinary skill and are intended by the inventor to be encompassed by the following claims. | A process of producing a thermoplastic starch/polymer blend involves introducing dry starch into a twin-screw extruder at a first location along the extruder, introducing a plasticizer into the twin-screw extruder at a second location along the extruder downstream of the first location to form a starch paste and then gelatinizing the starch paste in the extruder to form thermoplastic starch, and, introducing dry polymer at ambient temperature into the twin-screw extruder at a third location along the extruder downstream of the second location to form a blend with the thermoplastic starch in the extruder. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to navigating an image viewed on a display screen using a touchscreen.
[0003] 2. Background Information
[0004] A new era in TV viewing experience is emerging in which video complementary data services are available to the TV viewer using a second display screen on an auxiliary display device. One example of an auxiliary display device is a webpad, which is a relatively small remote wireless device.
[0005] [0005]FIG. 1 shows a conventional two-screen digital cable TV system 100 . The system 100 includes an auxiliary display device 105 which communicates with a digital set-top box (STB) 110 (also referred to as a “local device”) using a wireless connection. The wireless connection utilizes an external port 115 on the STB 110 , such as a Universal serial bus (USB), Ethernet, or IEEE 1394 port equipped with an access point 120 that communicates with the auxiliary display device 105 over a wireless radio frequency (RF) link 125 . The access point 120 in this scenario is a device designed for a specific interface (e.g., USB) and is used to support wireless connectivity. The auxiliary display device 105 may also be connected directly to a high-speed cable modem, digital subscriber (DSL) modem or any other high-speed Internet connection device to access the Internet 135 . TV video programming 140 is accessible via STB 110 . Typical wireless connection protocols that may be used by TV system 100 include, but are not limited to, HomeRF® and IEEE 802.11. A more traditional wired connection simply includes a cable or wire between the STB 110 and the auxiliary display device 105 , again using a USB, Ethernet, or IEEE 1394 port. The STB 110 is also connected to a television 130 .
[0006] The two-screen digital cable TV system 100 allows for many enhanced capabilities over a one-screen system. For example, a user can view Internet data on the screen of the auxiliary display device 105 , while watching video uninterrupted on the television 130 . In another example, STB applications that are normally viewed on the television screen, are viewed on the screen of the auxiliary display device 105 , leaving the television 130 available for video program viewing.
[0007] In a CATV system, an electronic program guide (EPG) is a specific example of an application that can be interacted with through an application running on a second screen device, such as auxiliary display device 105 . An EPG is used by a viewer to determine what programs are available for viewing on a television, at what time the programs will be broadcast, and on which channels. More sophisticated EPGs display supplemental information used by the viewer to determine whether the program is suitable for young children, what actors are in the program, how long the program is, and what the program is about. Normally in an EPG, an individual windowed portion is allocated for each program displayed. Viewers of CATV programs use a GUI to navigate an EPG and select program windows in the EPG that are of particular interest.
[0008] U.S. Pat. No. 6,130,726 (Darbee et al.) discloses a remote control display unit which selects programming shown on a television and displays images on a visual display. The remote control display unit disclosed in U.S. Pat. No. 6,130,726 includes an EZ NAV key used to navigate an EPG by moving up, down, left and right. U.S. Pat. No. 6,130,726 does not disclose using navigational control areas on a touchscreen to navigate an image.
[0009] Furthermore, many operating systems use scrollbars displayed on the X and/or Y axis margins of a display screen to allow an image on the screen to be navigated. Scrollbars take up a significant portion of the display that could be used to display a larger and less distracting view of the image.
[0010] Thus, it is desirable to navigate an image (e.g., EPG, game) displayed on a display of an auxiliary display device without using space consuming scrollbars or physical control devices such as a joystick, mouse, keys, or the like.
SUMMARY OF THE INVENTION
[0011] The present invention is a method and apparatus for navigating an image viewed on a display screen. The image is controlled by a processor that receives navigational commands selected on a touchscreen of an auxiliary display device. The touchscreen is partitioned into a plurality of navigational control areas. Each navigational control area is associated with a different navigational command. One of the navigational control areas is selected. The navigational command associated with the selected navigational control area is transmitted to the processor. The processor receives and executes the transmitted navigational command to navigate the image.
[0012] The image may have a plurality of selectable image portions. At least one of the selectable image portions may be currently highlighted for possible selection.
[0013] A center circular portion of the touchscreen may be defined and divided into four central navigational control areas and at least one entry control area. Four corner navigational control areas of the touchscreen may be defined. Each corner navigational control area may be adjacent to the center circular portion and located in a respective corner of the touchscreen.
[0014] Each of the navigational commands associated with the four corner navigational control areas may be used to change the x-axis and y-axis coordinates of the position of the at least one of the selectable image portions. Each of the navigational commands associated with the four central navigational control areas may be used to change one of the x-axis and y-axis coordinates of the position of the at least one of the selectable image portions. Each navigational control area may be associated with a different navigational command that changes the image portion that is highlighted from the currently highlighted image portion to a image portion adjacent to the currently highlighted image portion when the different navigational command is executed by the processor.
[0015] The partitions of the touchscreen may further include at least one entry control area. The entry control area may be selected to activate a function associated with the currently highlighted selectable image portion.
[0016] The boundaries of the control areas may be hidden from view and may be revealed on the touchscreen in response to a user input. Either a stylus or a finger of a user may be pressed against the touchscreen to select the one navigational control area. The image may include a television program grid of an electronic program guide (EPG) including a plurality of adjacent program windows. The selection of the one navigational control area may cause a specific program window adjacent to a previously highlighted program window to be highlighted for possible selection in accordance with the executed navigational command. The image may be navigated to play a game.
[0017] The apparatus includes the partitioned touchscreen and a transmitter for transmitting the navigational command associated with the selected navigational control area to the processor. The apparatus may be an infrared (IR) consumer electronic device. The processor may be located in a set-top box (STB) and the display screen may be a television in communication with the STB.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The following detailed description of preferred embodiments of the present invention would be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present invention, there are shown in the drawings embodiments which are presently preferred. However, the present invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
[0019] [0019]FIG. 1 shows a conventional two-screen digital cable TV system;
[0020] [0020]FIG. 2 shows a graphical user interface on the display of an auxiliary display device in accordance with the present invention;
[0021] [0021]FIG. 3 shows a system for selecting and processing commands used to navigate an image viewed on a display screen in accordance with the present invention;
[0022] [0022]FIGS. 4A, 4B and 4 C, taken together, show an example of how an image viewed on a display screen is navigated in accordance with the present invention; and
[0023] [0023]FIG. 5 shows a high-level functional flowchart including steps implemented by the apparatus shown in FIGS. 2 and 3.
DETAILED DESCRIPTION OF THE INVENTION
[0024] [0024]FIG. 2 shows an auxiliary display device 200 operating in accordance with a preferred embodiment of the present invention. The auxiliary display device 200 includes a touchscreen (touch screen) 205 , a processor 215 , an application program 225 running on the processor 215 , and a transmitter 245 . The auxiliary display device 200 is used for navigating an image viewed on a display screen.
[0025] A basic touchscreen has three components, a sensor, a controller, and a driver. A touchscreen sensor is a clear panel that fits over the display of the auxiliary display device. A software driver allows the touchscreen to interface with an operating system by translating touch events detected by the touchscreen sensor into navigational commands. A touchscreen controller processes signals received from the touchscreen sensor. Several types of touchscreen technologies are presently used:
[0026] 1. Resistive;
[0027] 2. Surface acoustic wave; and
[0028] 3. Capacitive.
[0029] A resistive touchscreen consists of glass or acrylic panel that is coated with electrically conductive and resistive layers. The thin layers are separated by invisible separator dots. When operating, an electrical current moves through the touchscreen. When pressure is applied to the screen by a finger or stylus, the layers are pressed together, causing a change in the electrical current and a touch event to be registered.
[0030] Surface acoustic wave technology is based on sending acoustic waves across a clear glass panel with a series of transducers and reflectors. When a finger or stylus touches the screen, the waves are absorbed, causing a touch event to be registered.
[0031] A capacitive touchscreen consists of a glass panel with a capacitive (charge storing) material coating its surface. Circuits located at corners of the screen measure the capacitance of a person touching the screen. Frequency changes are measured to determine the X and Y coordinates of the touch event.
[0032] The application program 225 partitions the touchscreen 205 into a plurality of navigational control areas 210 , 220 , 230 , 240 , 250 , 260 , 270 , 280 and at least one entry control area 290 . Each navigational area is associated with a different navigational command. Navigational control area 210 is associated with an “up” navigational command. Navigational control area 220 is associated with a “down” navigational command. Navigational control area 230 is associated with a “left” navigational command. Navigational control area 240 is associated with an “right” navigational command. Navigational control area 250 is associated with an “up & left” navigational command. Navigational control area 260 is associated with a “down & left” navigational command. Navigational control area 270 is associated with an “up & right” navigational command. Navigational control area 280 is associated with a “down & right” navigational command. A stylus or a user's finger is pressed against the touchscreen 205 to select different navigational control areas, even while an application unrelated to the image to be navigated is currently displayed on the touchscreen 205 . The touchscreen 205 does not display the image that is being navigated.
[0033] [0033]FIG. 3 shows an example of a system 300 that implements the present invention. The system 300 includes the auxiliary display device 200 , a display control device (e.g., set-top box (STB)) 305 and an image display screen 320 (e.g., a television). Display control device 305 includes a receiver 310 and a processor 315 . The processor 315 receives navigational commands from the auxiliary display device 200 and controls an image viewed on the display screen 320 . When a user selects a navigational control area on touchscreen 205 , a navigational command associated with the selected navigational control area is generated or retrieved from a memory (not shown) by processor 215 and forwarded to transmitter 245 for transmission over either a wired or wireless medium. Receiver 310 in display control device 305 receives the transmitted navigational command and forwards the command to the processor 315 in STB. The processor receives and executes the transmitted navigational command navigates the image accordingly.
[0034] In one embodiment, as shown in FIGS. 4A, 4B and 4 C, the image has a plurality of selectable image portions. At least one of the selectable image portions is currently highlighted for possible selection by the user of the auxiliary display device 200 . The user can activate a function associated with the currently highlighted selectable image portion by selecting the at least one entry control area 290 (see FIG. 2). The particular navigational command associated with the selected control area is executed to change the selected portion from a currently selected portion displayed at a first location on the display screen 320 to a different selected portion displayed at a second location on the display screen 320 according to the executed command.
[0035] In one preferred embodiment, a selected navigational command is translated into a wireless signal and is transmitted via transmitter 245 to the display control device 305 for controlling which portion of the image viewed on the image display screen 320 is selected
[0036] When a user selects one of the defined control areas 210 , 220 , 230 , 240 , 250 , 260 , 270 , 280 on the touchscreen 205 of the auxiliary display device 200 by a stylus- or finger-initiated touch in that area, one or more navigational command signals are transmitted to the set-top box display control device. The signals can take the form of infrared (IR) or wireless radio frequency (RF) signals. Alternatively, navigational command signals can be transmitted over a wired interface using typical wired protocols, such as Ethernet, USB, 1394, or the like.
[0037] The image viewed on display screen 320 can include a television program grid of an electronic program guide (EPG) including a plurality of adjacent program windows A-X, which correspond to a particular channel and/or time slot during which programming is to commence. The selection of the one navigating control area on touchscreen 205 causes a particular program window adjacent to a previously selected window to be selected in accordance with the executed command.
[0038] [0038]FIG. 4A shows an example of navigating a program grid viewed on image display screen 320 using the present invention, where program window P is currently highlighted for possible future selection. If navigational control area 230 (Left) is selected, program window O is highlighted instead of program window P, as shown in FIG. 4B. Then, as shown in FIG. 4C, if navigational control area 250 (Up & Left) is selected, program window H is highlighted instead of program window O. If entry control area 290 is selected while window H is highlighted, a function associated with window H, such as a hyperlink or a second window, is activated when processor 315 in the display control device 305 receives and executes a corresponding entry command from auxiliary display device 200 .
[0039] A currently displayed program grid may show only a portion of the total program grid, such as only a three-hour time window or only a portion of the available channels. If so, then additional portions of the program grid may be revealed if a user reaches an edge of the currently displayed program grid and selects a navigational control area that would go past the edge. Such a selection is ignored if the currently displayed program grid shows the total program grid.
[0040] When the user wants to implement a combination move by selecting one of navigational control areas 250 , 260 , 270 , 280 , the application 225 running on processor 215 in the auxiliary display device 200 causes two sequential commands to be transmitted from the auxiliary display device 200 to the display control device 305 , just as if a user individually selected two of navigational control areas 210 , 220 , 230 , 240 in sequence. Alternatively, a single “combination” command can be transmitted.
[0041] The image viewed on the display screen 320 can also be navigated to play a game (e.g., Pac-Man™, Space Invaders™, or the like) by moving game pieces or other images in the same fashion as described above.
[0042] In other preferred embodiments of the present invention, the navigational control areas may be used to cause an action or function to occur with respect to whatever application is currently executing on the STB 305 and being shown on the display screen 320 . Each application may have a different set of actions or functions that occur with respect to particular navigation commands. In some applications, such as the EPG application described above, selection of a navigation control area causes a navigation function to occur (e.g., selection of the left navigation control area 230 causes a movement to the left, selection of the down navigation control area 220 causes a downward movement). However, in another application, selection of a navigation control area may not necessarily cause a navigation function to occur. For example, the navigation control areas may cause different actions or functions to occur, such as mode changes or item selections. A mode change or item selection may not necessarily cause the movement of anything on a display screen. The scope of the present invention includes such alternative embodiments.
[0043] [0043]FIG. 5 shows a flow chart including steps for navigating an image shown on display screen 320 using an auxiliary display device 200 . An application 225 is run on a processor 215 within the auxiliary display device 200 which partitions the touchscreen 205 into a plurality of navigational control areas 210 , 220 , 230 , 240 , 250 , 260 , 270 and 280 and at least one entry control area 290 (step 505 ). Each navigational control area 210 , 220 , 230 , 240 , 250 , 260 , 270 , 280 is associated with a particular navigational command that changes the selection of a portion of an image viewed on the display screen 320 . One of the navigational control areas is selected (step 510 ). The particular navigational command associated with the selected control area is transmitted from the auxiliary display device 200 to the processor 315 in STB 310 (step 515 ). In step 520 , the processor 310 in display control device 305 navigates an image viewed on display screen 320 based on the transmitted navigational command. Each time another one of the navigational control areas is selected (step 525 ), steps 510 , 515 and 520 are repeated.
[0044] The present invention may be implemented with any combination of hardware and software. If implemented as a computer-implemented apparatus, the present invention is implemented using means for performing all of the steps and functions described above.
[0045] The present invention can be included in an article of manufacture (e.g., one or more computer program products) having, for instance, computer useable media. The media has embodied therein, for instance, computer readable program code means for providing and facilitating the mechanisms of the present invention. The article of manufacture can be included as part of a computer system or sold separately.
[0046] It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. | A method and apparatus for navigating an image viewed on a display screen. The image is controlled by a processor that receives navigational commands selected on a touchscreen of an auxiliary display device. The touchscreen is partitioned into a plurality of navigational control areas. Each navigational control area is associated with a different navigational command. When one of the navigational control areas of the touchscreen is selected, the navigational command associated with the selected navigational control area is transmitted to the processor. The processor receives and executes the transmitted navigational command to navigate the image. The boundaries of the control areas are normally hidden from view, but can be revealed on the touchscreen in response to a user input. | 7 |
BACKGROUND OF INVENTION
Field of the Invention
[0001] The present invention relates generally to netting structures. More specifically, the invention relates to a netting structure that serves as a safety net used on construction sites to catch debris or construction personnel from falling to the ground. The present invention provides an improved netting structure that eliminates the need to use a metal cable along the perimeter of a beam to support the net that typically requires the net to be clipped to the cable in several locations along its perimeter. The present invention also provides an assembly for guiding ropes used to pull the netting structure in place and secure the netting structure to a building frame.
Description of the Related Art
[0002] Any discussion of the prior art in the specification should in no way be considered as an admission that the prior art is widely known or forms part of common general knowledge in the field.
[0003] The use of safety nets on construction sites is often desirable. Safety nets are netting structures that are typically installed either around the perimeter of a building or beneath the area of a floor in a building frame where the building is being constructed, refurbished, or repaired. A properly installed netting structure enables the netting to catch any debris or construction personnel from falling to the ground and causing injury or death.
[0004] FIG. 1 illustrates a basic two-story building frame. A typical netting structure is installed around the inner perimeter of the horizontal beams as personnel work on the building above the net. FIG. 2 illustrates a detailed view of the prior art netting structure. The existing netting structure typically requires a metal cable, or series of metal cables, to first be installed around the inside of the horizontal beams of the building frame as shown. A net is then coupled along to the cable along its length typically by using metal hooks at several locations around the cable. This method of installation creates sag in the mesh of the netting structure based on the tension of cable. It also creates sag by scalloping of the border and the netting structure's mesh between each hook. This scalloping can only be reduced by adding closer hooks, but can be difficult, if not impossible, to eliminate. Furthermore, tightening the net generally requires the mesh and netting structure border to be pulled toward the cable for connection. This can be extremely difficult due to the elevated location of the netting structure and the many connection points that must be made.
[0005] As shown in FIG. 3 , the sagging in the prior art netting structures is sometimes addressed by installing additional ropes under the mesh or weaving them into the mesh to create pockets between the slack mesh. Each rope will slacken with the perimeter or border of the netting structure if it is attached to a point on the perimeter. If the rope is pulled separately, it requires two additional tie-off points per rope, which is inefficient. These ropes also create points of possible injury or death as a person falling into the net may hit a tensioned rope instead of the mesh. It is also possible to gather the mesh to the border rope with straps, however this does not reduce the border length.
[0006] The installation of these types of netting structures at construction sites can be difficult. Because these structures are typically installed high above the ground, they are often hard to reach and require special equipment, scaffolding, or ladders to lift the nets and the personnel who install them to the areas where they are secured to the beams on the building frame. Also, because the netting structures generally are designed have the perimeter of these structures cover as much area of the work area below to prevent even small objects from falling close to the building, it is very difficult for personnel to access the structure to move, maintain, or adjust it without disassembling large parts, or even the entire structure. If personnel need to gain access to the structure to adjust or move the it by loosening it at any point along its perimeter, it may lead to greater sagging or scalloping.
[0007] Another limitation to the present netting structures is that the nets themselves generally have to be built to fit within the size of the horizontal beams of the building frame.
[0008] The present invention overcomes the limitations in the prior art addressed above, and provides a solution that is both easy to install and use.
[0009] When installing vertical netting structures on the outside of a building frame to prevent debris and personnel from falling off the side of a horizontal beam, it is desirable for the vertical net to be some distance away from the frame building to allow workers to have freedom to move, and also to allow horizontal beams to possibly be installed into the building frame at a later time. The prior art typically requires a flag pole type design that is secured to a vertical beam where the netting structure attaches to a support point and drapes below the support point as shown in FIG. 3A . Or it requires a separate cantilever arm type system that needs to hold the net out at least 13 feet per standards and regulations. The present invention offers a solution to these limitations that eliminates the need to use flag pole designs and cantilever arms, still enables the vertical netting structure to rest a distance away from the frame structure, and is also easy to install by using pull ropes.
[0010] Other limitations to the present netting structures pertain to the hardware used to secure the structures to the building frames, and guide the ropes used to raise the structures in place. When installing safety nets, if a metal cable is not used to secure the netting structure around the beams of a building frame, a rope is usually tied to one end of an attachment point and then pulled through a large pulley or wooden block and tackle (wooden block and tackle will also be referred to as a “pulley”). Often the wooden pulleys are similar to those used on a sailing ship to guide ropes to raise sails to their operating position. There are several limitations to using this method. One limitation is that the pulley is typically coupled to a vertical beam using a clip. When under tension, a rope that is run through the pulley causes the pulley to move toward the attachment point of the netting structure, which creates a large gap between the beam and the netting structure as shown in FIG. 3B . The larger the length of the pulley, the larger the gap becomes between the bracket and the netting structure.
[0011] Another issue is how the pulley attaches to the netting structure. The pulley most often secured to a bracket on a vertical beam of the building structure. An eyebolt is then used to couple the pulley to the bracket. A cable or rope is threaded through the pulley or run through the eye of the eyebolt as secured to a vertical beam. An eyebolt is typically designed and rated for a direct pull load. The eyebolt is often not at the start in a shear side or angle load. This is not a correct engineered system and can lead to injury or death. In most cases pulleys are installed in the corners of the building frame. This means when the pulleys are under tension, they are likely being pulled away from the vertical beams even though ideally they should run vertically alongside or underneath the vertical beams.
[0012] Another limitation is the fact a pulley is designed to only allow the diameter of rope to pass through and nothing else. Any knot, splice, hook, or other attachment method would not allow these additional components to pass through the pulley as shown in FIG. 3C and would add additional space between the netting structure and the building frame as shown in FIG. 3B .
[0013] It is desirable to provide component hardware that enables safety netting structures to be installed to a building frame that does not create additional open space between the building frame and a safety net when installed under tension, and also to provide attachment and guide hardware that allows ropes with additional knots, splices, hooks, or related attachments to pass through them when raising the netting structures in place that is effective and easy to install.
SUMMARY OF THE INVENTION
[0014] The invention is summarized below only for purposes of introducing embodiments of the invention. The ultimate scope of the invention is to be limited only to the claims that follow the specification.
[0015] It is an object of this invention to provide a netting structure that is secured to the horizontal beams of a building frame to catch falling debris or personnel within the building structure.
[0016] It is an object of this invention to provide a netting structure that has a primary border, that is typically a rope, that is coupled to the entire outer edge of the netting structure.
[0017] It is an object of the present invention to provide a netting structure that has a secondary border, that is typically a rope, that is fixed at two points on the primary border to form an attachment point.
[0018] It is an object of the present invention to provide a netting structure wherein the primary and secondary borders are coupled by one or more clips.
[0019] It is an object of the present invention that when the clips are not coupled to the primary and secondary borders, the portion of the netting structure coupled to the primary border near the secondary border, drops downward and creates an opening between the primary and secondary borders.
[0020] It is an object of the present invention to provide a netting structure wherein the secondary border can be two distinct ropes connected by their respective ends to the primary border at distinct locations along the primary border.
[0021] It is an object of the present invention to provide a netting structure with a resilient rod that is coupled to two sides of the outer edge of the netting structure.
[0022] It is an object of the present invention to provide a rectangular ring with two pairs of rollers axially coupled within the inside of the rectangular ring such that each respective pair of rollers is parallel to each other and perpendicular to the other respective pair of rollers.
[0023] It is an object of the present invention that the rollers are able to rotate freely about their respective axes within the rectangular ring.
[0024] It is a further object of the present invention to provide a pulley that is axially coupled to a bracket that is connected above the rectangular ring so that the pulley is capable of rotating freely about its axis with the pulley being parallel to at least one of the rollers within the rectangular ring.
[0025] It is an object of the present invention that the rectangular ring is of sufficient cross-sectional area to enable objects large enough to pass through its cross-sectional area when a rope is connected to the objects as the rope is being used to pull the netting structure toward a point on the building frame.
[0026] It is an object of the present invention to provide an adjustable member that is connected to the rectangular ring so that the adjustable member can be coupled on one end to a vertical beam of the building structure and allow the adjustable member to move the position of the rectangular ring to and from the vertical beam of the building frame.
[0027] A person with ordinary skill in the relevant art would know that any shape or size of the elements described below may be adopted as long as the end clamp can be used to secure solar panel modules to the rail support structures and a binding bolt is used to tighten the t-bolt to the guide of the rail support structure. Any combinations of suitable number, shape, and size of the elements described below may be used. Also, any materials suitable to achieve the object of the current invention may be chosen as well.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] A more complete understanding of the present invention may be derived by referring to the detailed description and claims when considered in connection with the following illustrative figures. In the following figures, like reference numbers refer to similar elements and steps throughout the figures.
[0029] FIG. 1 illustrates a basic two-story building frame.
[0030] FIG. 2 is a top view of prior art net and connection to a cable.
[0031] FIG. 3 is a top view of prior art net with additional ropes to hold up sag and slack mesh.
[0032] FIG. 3A is a prior art shows means of attaching a net/flap to an outrigger flagpole type of support.
[0033] FIG. 3B is a side view of prior art.
[0034] FIG. 3C is a side view detail of prior art.
[0035] FIG. 4 is a top view of an exemplary embodiment of the netting structure.
[0036] FIG. 5 is a front view of an exemplary embodiment of the netting structure and hardware installed on test frame.
[0037] FIG. 6 is a top view of details of a corner in FIG. 4 .
[0038] FIG. 7 is a view of FIG. 6 with a split secondary rope.
[0039] FIG. 8 is a top and slightly forward view of FIG. 7 with primary border and mesh gathered.
[0040] FIG. 9 is a bottom and slightly forward view showing an alternate embodiment using a smaller net to protect a partial area.
[0041] FIG. 10 is a top view of one corner of embodiment on test frame with slight adjustment on only one side.
[0042] FIG. 11 is a front view of FIG. 8 .
[0043] FIG. 12 is a top and slightly forward view of FIG. 6 with corner open.
[0044] FIG. 13 is a top view of details of a corner in FIG. 4 with mesh hung square.
[0045] FIG. 14 is a top view of an alternate embodiment with flap manufactured attached to embodiment in FIG. 4 .
[0046] FIG. 15 is the same as FIG. 14 .
[0047] FIG. 16 is a bottom and slightly forward view of flap and resilient spreaders connected to embodiment in FIG. 4 with snap hooks installed on test frame.
[0048] FIG. 17 is a bottom and slightly angled view of FIG. 16 .
[0049] FIG. 18 is a cutaway partial view of a resilient spreader shown in FIG. 16 .
[0050] FIG. 19 is a forward view of a resilient spreader similar to FIG. 18 that does not require an outer jacket.
[0051] FIG. 20 is a side view of an alternate embodiment showing the push guide with removable roller, and pivot.
[0052] FIG. 21 is the same as FIG. 20 except a split ring is substituted for the guide with removable roller and pivot.
[0053] FIG. 22 is a perspective view of a guide ring attached to a bracket.
[0054] FIG. 23 is a bottom view of alternate embodiment showed in FIGS. 16 and 17
[0055] FIG. 24 is a side view of the element in FIG. 21 installed but does not pivot.
[0056] FIG. 25A is a side view of the guide ring of FIG. 25 .
[0057] FIG. 25B is a bottom view of the guide ring of FIG. 25 .
[0058] FIG. 25C is a side view of the guide ring of FIG. 25 .
[0059] FIG. 26 is a perspective view of the pull point shown in FIG. 29 with a pulley.
[0060] FIG. 27 is a side view of the netting structure assembled to a building structure.
[0061] FIG. 28 is an alternate view of FIG. 27 .
[0062] FIG. 29 is a top view of a pull point.
[0063] FIG. 30 is a perspective view of a pull point with dual pulleys.
[0064] FIG. 31 is a perspective view of an assembly showing five pull points arranged on a bracket with dual pulleys.
[0065] FIG. 32 illustrates an alternate pull point/pulley embodiment.
[0066] FIG. 33 illustrates a side view of a rope moving through the embodiment in FIG. 32 .
[0067] FIG. 34 illustrates an alternate embodiment of FIGS. 27 and 28 showing the assembly featuring the guide ring connected to the vertical beam above the pull point.
DETAILED DESCRIPTION OF THE INVENTION
[0068] FIG. 4 shows a top view of an exemplary netting structure 100 and FIG. 5 shows a typical four-column beam building structure 105 with horizontal beams 107 and vertical beams 108 and with the netting structure 100 installed. The netting structure 100 includes a mesh 110 that is coupled to a border rope 120 . The mesh 110 can also be loose around the border rope 120 by weaving the border rope 120 into the mesh 110 . The mesh 110 can be of different forms such as straight or diamond-shaped netting or webbing. The border rope 120 in this embodiment is typically a single rope that encircles the entire outer edge of the mesh 110 and then forms two distinct ropes—a primary corner rope 130 and a secondary corner rope 140 —where the attachment points 150 are located. The outer edge can include the outermost perimeter of the mesh, but it can also include some of the inner portion of the mesh 110 as well and is not restricted to the outermost perimeter of the mesh. The border rope 120 is typically fixed to the mesh 110 along the inner perimeter and along the primary corner rope 130 , although the border rope 120 could be woven through the mesh 110 along the perimeter so that the mesh 110 can move separately along the border rope 120 . The term “rope” can include any suitable cord, twine, or string that is of sufficient strength to remain intact under large pulling forces.
[0069] Although the netting structure 100 shown is rectangular in shape, the structure 100 can be any suitable shape such as a triangle, trapezoid, or other geometric shape to conform to the shape of the building structure's vertical beams. The shape of the structure 100 is defined by the number and location of the attachment points 150 along its perimeter. The attachment points 150 are generally defined by the point where secondary corner rope 140 is attached to a means for pulling the netting structure 100 toward the building structure 105 . In an embodiment that employs a single secondary rope 140 , the attachment point 150 is usually where the loop of rope is formed in FIG. 6 , or it can be where the two separate border lines or ropes 143 and 146 are located as shown in FIG. 7 . The border lines are preferably ropes, but can also be a cord, twine, string or rope-like structure that can be used under high tension forces to pull the netting structure 100 into place.
[0070] Other embodiments of the structure 100 utilize dual border ropes that encircle the perimeter of the mesh 110 . In a dual border rope configuration, one rope acts as the primary border rope that is fixed along the entire perimeter of the mesh, while the second rope is fixed only to the inner perimeter of the mesh 110 with the non-fixed portions serving as the attachment points 150 in each corner of the structure 100 . The border rope 120 can also include more than two ropes as long as they are secured to a portion of the mesh 110 along each side of the netting structure 100 . Near each attachment point 150 , a plurality of clips 160 connect the primary corner rope 130 with the secondary corner rope 140 . The clips 160 are generally snap hooks, rings, quick hooks, or any suitable clip capable of coupling the mesh 110 to the primary and secondary corner ropes 130 and 140 under high stress loads.
[0071] FIG. 6 shows a detailed view of the attachment point 150 in the structure 100 . The clips 160 are free-floating along the length of the split between the primary corner rope 130 and secondary corner rope 140 .
[0072] FIG. 7 shows an alternate embodiment where the secondary corner rope 140 is divided into two secondary ropes 143 and 146 respectively. Additional connecting hardware can be added to the open ends of each rope 143 and 146 so that they can be coupled to a pulling means, such as a rope, for tightening. With the two ropes 143 and 146 , each side of the netting structure 100 connected to the ropes 143 or 146 can be independently pulled toward a point on one of the horizontal beams 107 on the building structure 105 as shown in FIG. 9 . In that case, the rope 143 or 146 can be pulled to bring the perimeter of the structure 100 closer to a side of the work area where protection and safety is necessary, and away from a side where it's not needed as shown in FIG. 10 .
[0073] FIG. 4 shows a top and slightly forward view of FIG. 7 with the primary corner rope 130 and mesh 110 gathered together. In the case where only one secondary corner rope 140 is used, the rope 140 is also free moving and allows the rope 140 to self-place along the length to allow tensioning of both sides of the netting structure 100 that are connected to the rope 140 . FIG. 11 is a side view of FIG. 8 and shows the mesh 110 near the attachment point 150 slacking below the plane of the netting structure 100 , while the mesh 110 connected to the border rope 120 remains in tension.
[0074] FIG. 12 shows the same attachment point 150 with the clips 160 removed from the secondary corner rope 140 (in the embodiment where the secondary corner rope 140 is cut, the clips 160 are removed from the secondary ropes 143 and 146 ). In this exemplary embodiment, with the clips 160 removed, the mesh 110 falls downward and creates an open space 162 in the area nearest the attachment point 150 . As shown in FIG. 13 , when the clips 160 are connected, the mesh 110 remains in tension everywhere else throughout the netting structure 100 . Even when the clips 160 are removed and an opening 162 is created in the area, the mesh 110 along the border rope 120 will still remain in tension. This enables personnel to access the structure 100 by way of a ladder or other mechanical means to more easily climb through, or work through the open area 162 without disrupting the tension in the mesh 110 .
[0075] In another embodiment, a second netting structure 200 , as shown in FIGS. 14 and 15 , can be added to a side of the netting structure 100 . As shown in FIGS. 16 and 17 , the second netting structure 200 (also referred to as a “flap”), typically functions as a vertical border net along the outer portion of the construction frame to protect debris and personnel from falling off the side of the frame. It can also be used to span a gap between two horizontal netting structures 100 . The flap 200 is typically raised upward using a pulling rope along the outside area of the construction frame beneath a horizontal beam 107 as shown in FIG. 17 . The flap 200 can either be pre-manufactured as a single structure with the mesh 210 and mesh 110 sharing the border rope 120 , or the flap 200 can be a separate structure such that the mesh 210 is secured to its own flap border rope 220 and subsequently secured to the netting structure 100 along the border rope 120 . The end of the flap border rope 220 that is not connected the border rope 120 is a flap primary corner rope 230 . As shown in the close up view in FIG. 14 , the flap primary corner rope 230 also approaches the attachment point 150 . The flap primary corner rope 230 is coupled to the secondary corner rope 140 by clips 160 in the same manner that the primary corner rope 130 of the netting structure 100 is coupled to the secondary corner rope 140 so that the mesh 210 can be opened and lowered in the same fashion as the mesh 110 .
[0076] In the flap 200 , the plane of the mesh 210 also includes a member or rod 270 as shown in FIG. 16 . In the exemplary embodiment, the rod 270 is generally resilient and spans lengthwise across the mesh 210 from one end of a border of the flap 200 to the opposite side of the flap 200 . The rod 270 serves two primary purposes. First, the rod 270 prevents the mesh 210 from snagging or clumping together before the flap 200 is raised to its destination, and second, when the flap 200 is pulled up by a pulling rope, the beam 107 below causes the rod 270 to bend and hold the netting structure 200 away from the beam on which the worker is positioned as shown in FIGS. 16 and 17 . This enables the flap 200 to flex and conform to the building frame itself. If the horizontal beam 107 is not installed in advance, the rods 270 allow for the beam 107 to be dropped in place from above, and the rods 270 will deflect pushing the mesh 210 away from the beam 107 so the beam 107 can be installed.
[0077] In the exemplary embodiment, the rod 270 is embedded within a sleeve 280 as shown in FIG. 18 and is coupled to the border rope 120 on one side and runs perpendicular to the border rope 120 across the mesh 220 to the opposite end 290 of the mesh 210 . Other suitable ways to secure the rod 270 to the netting structure 100 include fixing the sleeve 280 to the mesh 210 itself, or using a clip 160 through a grommet 285 , as shown in FIG. 18 , to one of the loops in the mesh 210 or to the border rope 120 and opposite end 290 . Generally, more than one rod 270 is used depending on the size of the plane area of the mesh 210 . If used, multiple rods 270 are typically vertically spaced apart a given distance to provide rigidity throughout the entire plane of the mesh 210 .
[0078] An alternate embodiment of the rod 270 is shown in FIG. 19 . The rod 270 has a resilient length with a pair of snap hooks 272 or other similar connecting means on each end so that they can be secured to the opposite end 290 and border rope 120 of the flap 200 by way of a clip 160 .
[0079] An alternate way of raising the flap 200 and keeping it a desired distance from the building frame 105 is by using a push interim support 400 as shown in FIGS. 20 and 21 . The push interim support 400 pushes the flap 200 away from the structure for easier access to the beams 107 and 108 . It differs from the flag pole method in the prior art as shown in FIG. 3A as it directs the flap 200 away from the building frame, while still leaving the push interim support 400 and movement (pull) point 420 above the flap 200 as shown in FIGS. 23 and 24 . This also allows for adjustment in and out depending on the requirement.
[0080] The embodiment in FIG. 20 of the push interim support 400 includes an adjustable member 405 that further comprises a base connector 430 with a pivot adjustment 425 on one end, and a removable roller structure 500 that contains a rope slot 510 on the other end of the adjustable member 405 . FIG. 21 shows a slightly different embodiment with a split circular rope slot 520 on one end of the adjustable member 405 . The pivot adjustment 425 is beneficial so that the flap 200 can be preinstalled and held flat against the building frame 105 while the beam 107 is being raised in place. The pivot adjustment 425 also allows for the unit to be put in place while the flap 200 is in tension. The flap 200 can be installed in place in a vertical position. Then the flap 200 can be pushed down or pulled up in to an angled or horizontal position. The flap 200 can then later be removed. All operations can be done while the flap 200 and the pull rope 350 remain in tension. This is not possible the prior art options.
[0081] Exemplary embodiments of guide assemblies used to secure the netting structure 100 or flap 200 in place to the building frame 105 include a guide ring 600 , a roller 700 , and a pulley 800 .
[0082] FIGS. 22, 25A, 25B, and 25C show a guide ring 600 . The guide ring 600 is typically hollow and circular in the shape of a ring, but it can be of any suitable shape that allows a rope, a rope knot, splice, or clip hardware to pass through it. The guide ring 600 is preferably made of a durable material, such as metal, that can withstand substantial tension forces. The guide ring 600 is coupled to a bracket 610 , which in turn is secured to a vertical beam 108 with a ratchet or other securing means through slot 611 so that the plane of the guide ring 600 is oriented parallel to the ground. The ring 600 and bracket 610 can be homogeneous or constructed in separate parts. When secured to the beam 108 , the ring 600 serves as a guide for a pull rope 350 to pass through along the beam 108 . Multiple rings can be secured to the same bracket 610 if desired.
[0083] FIG. 29 illustrates a single pull point 700 . The pull point 700 is generally hollow and rectangular in shape. The pull point 700 includes a pair of top rollers 710 and a pair of bottom rollers 715 . The rollers 710 are typically cylindrical structures that are capable of freely rotating around a pin, but any suitable rotational mechanism would be sufficient as well. Each top roller 710 is axially coupled to the inside of the pull point 700 by a pin 720 that enables the top roller 710 to freely rotate in either a clockwise or counter-clockwise direction. The top rollers 710 are preferably arranged so that they are parallel to each other and are axially coupled on opposite sides of the pull point 700 to each other in the same plane as shown. More than two rollers 710 can be added that are within the same plane as long as the inside area of the pull point 700 is large enough to allow ropes, connecting hardware, and even nets without secondary border ropes 140 and mesh 110 to pass through it. The bottom rollers 715 are also axially coupled to the inside of the pull point 700 , but sit either above or below the top rollers 710 and are perpendicular to the top rollers 710 . It is understood by one of ordinary skill that multiple levels of rollers can be added inside the pull point 700 as long as the outer edge 730 of the pull point 700 is deep enough to accommodate the extra layers.
[0084] Like the guide ring 600 , the pull point 700 is preferably made of a durable material, such as metal, that can withstand substantial tension forces. The pull point 700 is coupled to a bracket 610 , which in turn is secured typically to the same vertical beam 320 above the guide ring 600 . The bracket 610 is typically secured with a ratchet so that the plane of the pull point 700 is oriented parallel to the ground, but it can also be bolted to the vertical beam 108 as well. The pull point 700 and bracket 610 can be homogeneous or constructed in separate parts. Any arrangement of the top rollers 710 and bottom rollers 715 preferably should provide sufficient open area in the center of the pull point 700 to allow both rope 350 and connecting hardware to pass through the area. When secured to the beam 108 , the pull point 700 serves as a pulley-like structure that enables a pull rope 350 and certain connecting hardware to pass through the pull point's 700 center area as the rope 350 is being used to raise and secure the netting structure 100 at its attachment points 150 .
[0085] FIG. 26 shows another exemplary embodiment of the pull point 700 . A pulley 740 is coupled to a side 730 of the pull point 700 . The pulley 740 includes a wheel 750 that is axially coupled to a bracket 760 that sits above the rollers 710 or 715 . The wheel 750 is typically positioned in the center of the side 730 so that any rope that passes through it is centered as it passes through the pull point 700 . The wheel 750 generally has enough surface area so that any knot or clip 160 that is attached to the rope 350 can move be contained within the sides 770 of the wheel 750 .
[0086] FIG. 27 shows a side view of assembly that uses the guide ring 600 and pull point 700 (that includes pulley 740 ) in combination with each other and secured to the same vertical beam 108 . The pull point 700 is secured above the guide ring 600 on the beam 108 . The purpose of their simultaneous use is to allow rope 350 to efficiently provide tension to the attachment point 150 of the netting structure 100 so that the structure 100 can be as close to the beam 108 as possible and eliminate any open space between horizontal beams 107 and the netting structure 100 . The rope 350 is typically coupled to the attachment point 150 by connecting it to the secondary corner rope 140 , or if the secondary corner rope 140 has been split into two, connecting it to one or both of the separate secondary ropes 143 or 146 . This can be done by knotting the ropes together, or by coupling them with a clip 160 . The rope 350 is then threaded through the center of the pull point 700 and then downward so that it is threaded through the guide ring 600 as shown. The clip 160 typically can fit through the pull point 700 and the guide ring 600 . When the rope 350 is pulled downward (typically by a person standing on the ground or by mechanical means by using a ratchet for example, the secondary corner rope 140 is pulled in tension toward the pull point 700 as shown. In this configuration, the rope 350 and the secondary corner rope 140 engage the wheel 750 and rollers 710 so that when they rotate, the ropes move upward and downward with nearly no friction. This allows the netting structure 100 to be pulled right up against the pull point 700 and as close to the vertical beam 108 as possible. The pull point 700 and guide ring 600 prevent the rope 350 from moving outward and maintains vertical alignment with the vertical beam 108 .
[0087] An alternate embodiment of the assembly in FIG. 27 is shown in FIG. 28 . In this configuration, the rope 350 is first threaded through the guide ring 600 , upward through the pull point 700 , and then downward over the side of the pull point 700 as shown. In this case, the rope 350 is not directly next to the vertical beam 108 as it is being pulled downward to bring the netting structure 100 close to the vertical beam 108 . This same configuration of using the pull point 700 and the guide ring 600 can also be used to raise the flap 200 in place as shown in FIGS. 16 and 17 . An alternate embodiment of FIGS. 27 and 28 is shown in FIG. 34 .
[0088] FIGS. 30 and 31 show alternate embodiments of the pull point 700 . As illustrated, additional pulleys 740 can be secured to other sides 730 of the pull point 700 . Additionally, multiple bays of pull points 700 can be placed side-by-side around a bracket 610 . This embodiment utilizing multiple bays of pull points 700 is typically used when multiple netting structures 100 have to be installed on multiple floors. Several ropes can be pulled to raise and lower the netting structures 100 simultaneously.
[0089] FIG. 32 shows an alternate design of pull point 700 with pull point 703 , which combines the pull point 700 and guide assembly with a series of smaller rollers 770 . The series of rollers 770 carry the rope 350 over a larger radius ( FIG. 33 ) which may provide improved rope loading and can be used as a combined unit or just as a pull point 700 or guide assembly. FIG. 32 also shows how the bracket 610 can be bolted to steel or other surfaces, or strapped.
[0090] In the preceding description, and for the purposes of explanation, numerous specific details are provided to thoroughly understand the various aspects of the invention. It will be understood, however, by those skilled in the relevant arts, that the present invention may be practiced without these specific details. In other instances, known structures and devices are shown or discussed more generally in order to avoid obscuring the invention. In many cases, a description of the operation is sufficient to enable one to implement the various forms of the invention, particularly when the operation is to be implemented in software. It should be noted that there are many different and alternative configurations, devices and technologies to which the disclosed embodiments may be applied. The full scope of the invention is not limited to the example(s) that are described below. | In various representative aspects, a netting structure is configured to serve as a safety net used on construction sites to catch debris or construction personnel from falling to the ground. The netting structure eliminates the need to use a metal cable along the perimeter of a beam to support the net that typically requires the net to be clipped to the cable in several locations along its perimeter. An assembly for guiding the ropes used to pull the netting structure in place and secure the netting structure to a building frame is also provided. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to substituted 3-nitropyridine compounds used as sensitizers of hypoxic tumor cells to therapeutic radiation. It also relates to the process of preparing such compounds by aminating chloro-3-nitropyridines to produce the substituted 3-nitropyridines.
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, and are believed to have a more favorable therapeutic ratio.
DETAILED DESCRIPTION OF THE INVENTION
The compositions of the present invention are nitropyridine compounds of the formula ##STR1## wherein the NHCH 2 CHOHCH 2 OH group is attached at position 2, 4, or 6 of the pyridine ring.
The substituted nitropyridine compounds of the present invention are prepared in the following manner:
A (2,4 or 6)-chloro-3-nitropyridine of the formula: ##STR2## in a suitable solvent such as a lower aliphatic alcohol, or a polar aprotic solvent such as dimethylformamide, dimethylsulfoxide, or others such as tetrahydrofuran, glyme, diglyme, tetramethylurea, chloroform, or methylene chloride is treated with the selected amine reactant of the formula H 2 NCH 2 CHOHCH 2 OH, in the presence of sufficient base to neutralize the hydrogen chloride formed. The reaction temperature is not critical and may vary from 0°-100° C., preferably from about 0°-25° C. for a period of from 1-24 hours.
Suitable bases employed to neutralize the hydrogen chloride formed are tertiary amines such as triethylamine and pyridine. If desired, the neutralizing base may be supplied by using excess amine reactant. Inorganic bases such as alkali metal bicarbonates, carbonates and hydroxides may also be employed.
The product is recovered in substantially pure form by removal of solvent by evaporation under reduced pressure and the residue containing the product is chromatographed and crystallized from suitable solvents.
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 amount 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.
EXAMPLE 1
4-(2,3-Dihydroxy-1-propylamino)-3-nitropyridine
A solution of 4-chloro-3-nitropyridine (1.1 g, 6.94 mmol) and 3-amino-1,2-propanediol (1.22 g, 13.4 mmol) in isopropanol (50 ml) was stirred at 20°-25° C. for 20 hours and then concentrated under reduced pressure. Flash chromatography of the residue over silica gel and elution with 10% MeOH-90% CHCl 3 gave pure 4-(2,3-dihydroxy-1-propylamino)-3-nitropyridine (500 mg, 33.8%). An analytically pure sample, m.p. 131°-35° C., was obtained upon recrystallization from MeOH-EtOAc-hexane.
EXAMPLE 2
2-(2,3-Dihydroxy-1-propylamino)-3-nitropyridine
A solution of 2-chloro-3-nitropyridine (3.22 g, 20.3 mmol), 3-amino-1,2-propanediol (1.85 g, 20.3 mmol) and triethylamine (2.05 g, 20.3 mmol) in isopropanol (80 mL) was stirred at 20°-25° C. for 18 hours and then at reflux for 6 hours. After concentrating under reduced pressure, the residue was flash chromatographed over silica gel. Elution with 5% MeOH-95% CHCl 3 and recrystallization from EtOAc-hexane afforded analytically pure product (2.64 g, 61%), m.p. 95.5°-98.0° C.
EXAMPLE 3
The procedure of Example 2 was repeated using 3-nitro-6-chloropyridine in place of 2-chloro-3-nitropyridine to give 6-(2,3-dihydroxy-1-propylamino)-3-nitropyridine. | Substituted 3-nitropyridines are disclosed to have activity in increasing the sensitivity of hypoxic tumor cells to therapeutic radiation. Also disclosed are methods of preparing such compounds by amination of the corresponding chloro-3-nitropyridine with 2,3-dihydroxypropylamine and pharmaceutical compositions including such compounds. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to alarm systems and, more particularly, to a multi-zone alarm system for the detection and indication of an alarm condition in variously identified zones. Specifically, the present invention relates to an improved alarm system which monitors multiple zones with normally closed circuit sensing devices in a series connected circuit by means of a single pair wire.
2. Description of the Prior Art
In alarm systems employed to sense intrusion, fire or other conditions, techniques are known for the determination at a central location of the remote zone in which an alarm has occurred. Examples of such systems are illustrated in U.S. Pat. No. 4,274,087, No. 4,625,198 and No. 4,728,946. In such systems, a communications path is a generally established between each remote alarm sensor and a central location, the communications path being provided by means of a separate communications line from the central location to each remote station, or by use of a common communications line and multiplexed signaling techniques, such as time division multiplexing or frequency division multiplexing.
It is advantageous to employ a two-wire communications path forming a single alarm loop in which all alarm sensors are connected. Such a single loop can minimize the amount of wiring necessary to interconnect the central location with the remote sensors and can provide relatively simple and efficient connection of the remote sensors with the central location. It is typically required in an alarm system to provide the capability of identifying each sensor or each zone in which an alarm has occurred, and an example of this type of system is disclosed in U.S. Pat. No. 4,423,410. However, there remains quite a few drawbacks and limitations to existing two-wire systems available on the market including the ability to function both in the armed and disarmed modes as well as to indicate when the system has been cut during its disarmed mode.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the present invention to disclose a means of detecting and identifying a plurality of zones and provide indication of all conditions thereof.
It is another object of the present invention to provide a method of determining said conditions supplied from a single pair wire.
It is another object of the present invention to provide a device for determining the difference of any and all openings of the zoned loop, and a cut open loop condition, and provide indication thereof.
It is a further object of the present invention to provide a technique of selecting, or programming, all possible circuit arrangements of the zoned devices without the need of physical rewiring.
It is yet a further object of the present invention to provide a decoding receiver and annunciator providing indication as to conditions thereof.
It is also a further object of the present invention to provide a device for coding any utilized normally closed circuit device by means of placing a specific predetermined value resistor in a parallel circuit across the normally closed device switch.
It is also a further object of the present invention to provide a method of revising a single pole single throw switch to produce a two-state switch having a low and high state of resistance.
It is also a further object of the present invention when utilizing a four-zone detection system to provide the means of identification of all sixteen possible circuit combinations thereof.
It is also a further object of the present invention to provide a two-state mode of operation of the system, the operations being "Disarmed" and "Armed" modes.
It is also a further object of the present invention to provide a device which continuously monitors all circuit conditions in both modes of operations.
It is also a further object of the present invention to provide a means to latch on, or hold, any light emitting diode indicators which are activated while the system is in the "Armed" mode of operations.
It is also a further object of the present invention to provide a means to hold on any latched-on light emitting diode indicators which occur during the "Armed" mode, and to hold on any of such indicators when the system is "Disarmed".
It is also a further object of the present invention to provide a means of re-setting all latched-on light emitting diodes which have been activated during the "Armed" mode, the reset switch being reset only in the "Disarmed" mode of operations.
It is also a further object of the present invention to provide a means of determining whether and which zoned circuits are activated, if any of the zoned devices are presently open or closed, and if an alarm activation has occurred.
It is also a further object of the present invention to provide a means of monitoring all conditions during the "Disarmed" mode of operations with such conditions including all zoned circuit devices being open or closed circuit, closed loop circuit wire cut, low or no voltage to the system, system normal, loop circuit normal and closed, loop circuit voltage normal, and system mode being "Armed" or "Disarmed".
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, as embodied and broadly described herein, an apparatus is disclosed for use in a multi-zone alarm system having a single-pair wire alarm loop and programmable switching circuit arrangements. The apparatus includes a current source serially connected to the single-pair wire loop and selectively operative to provide a predetermined current signal in the loop. A plurality of zone sensing devices are arranged in a normally closed series circuit along the single-pair wire loop. Each of the zone sensing devices is adapted for generating coded voltage changes and alarm activation caused by an open circuit created therein. An element is provided for indicating the condition of each of the zone sensing devices, while a mechanism is provided for selectively arming and disarming the zone sensing devices. A circuit arrangement is provided for indicating an open circuit in the single-pair wire loop unrelated to the condition of the zone sensing devices, while another circuit is operative in response to the zone sensing devices to provide a signal indication of the zone in which alarm activation has occurred. Finally, a circuit mechanism is provided for continuously monitoring all circuit conditions of the apparatus in both the armed and disarmed operative conditions.
In a more specific embodiment utilizing four zone sensing devices, the control system provides for decoding any and all sixteen possible switching circuit arrangements of the four-zoned devices. The system also provides a mechanism for programming any and all of the thirty possible zone circuit switching configurations while further permitting more than one zoned device to be activated to cause an alarm condition. The system also provides a two-mode operation, "Disarmed" and "Armed", in addition to the twenty-four hour monitoring of all conditions. Finally, the system provides a circuit arrangement for reducing false alarms caused by short-term momentary opening detected in the zoned loop circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings which are incorporated in and form a part of the specification illustrate a preferred embodiments of the present invention and, together with a description, serve to explain the principles of the invention. In the drawings:
FIG. 1 is a block diagram of a preferred embodiment of the present invention;
FIG. 2A is a first partial circuit schematic of a preferred embodiment of the present invention;
FIG. 2B is a continuation of the partial circuit schematic of the preferred embodiment illustrated in FIG. 2A.
FIG. 2C is a continuation of the partial circuit schematic of the preferred embodiment illustrated in FIG. 2B.
FIG. 3 is a wiring diagram illustrating three examples of zoned circuit devices constructed in accordance with the present invention;
FIG. 4 is a truth table of programming the selector switches of a preferred embodiment of the invention;
FIG. 5 is a zone/voltage table of a preferred embodiment of the present invention;
FIG. 6 is a front plan view of the cover assembly of an apparatus constructed in accordance with the present invention;
FIG. 7 is a front plan view of the interior of the apparatus of the invention incorporating the circuitry illustrated in FIGS. 1 and 2; and
FIG. 8 is a wiring diagram illustrating two examples of wiring arrangements typical in the prior art for a plurality of zone circuit devices.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring in general to the Figures, the system of the invention detects and identifies any and all circuit openings which become open circuit. Each zoned circuit provides indication of all conditions of each of the four-zoned devices by means of four light emitting diodes which monitor continuously, twenty-four hours a day. In preferred form, the system has two modes of operation, "Armed" and "Disarmed". When in the "Disarmed" mode, should any of the zoned circuits become open, the associated zone light emitting diode becomes on, and upon closure the zone indicators return to off and do not latch on. In such an event, an alarm condition shall not occur.
When the device is in the "Armed" mode, any opening shall be indicated as being on and become latched-on and remain on until manually reset once the system has been returned to the "Disarmed" mode of operation. When the device is in the "Armed" mode, should an opening or openings occur which meet the criteria as programmed by the twelve combination switches, such an event will cause alarm activation.
Referring particularly, now, to FIGS. 6 and 7, since the system monitors all conditions twenty-four hours per day, and when in the "Disarmed" mode of operation, another distinct advantage is that any of the zoned closed circuit devices monitored provides a means of testing each utilized device. Moreover, the system provides complete monitoring of all conditions provided by eight separate colored light emitting diode indicators. Furthermore, four amber light emitting diodes provide indication as to the condition of each of the four-zoned devices.
The green light emitting diode, normally ON, indicates all zoned circuits are closed and the supply voltage to the system is normal. When OFF, it indicates one or more zoned circuits are open, and the open zones are indicated. When all zone indicators are Off and the green indicator is OFF, this indicates loss of power to the system. The orange light emitting diode provides indication as to the modes of operation. When OFF, it indicates the system is in the "Disarmed" mode of operation, and when ON, it indicates the system is in the "Armed" mode.
Two red light emitting diodes are provided. The first red indicator provides indication of alarm condition. When Off, condition is normal, and when ON, it indicates that an alarm activation has occurred. Once activated, the indicator is latched-on, and remains on until the system has been "Disarmed," at which point the reset switch is pressed. The second red indicator provides an indication of continuity of the closed circuit zone loop. When Off, it indicates that the system is normal. When ON, it indicates that the zoned closed loop circuit is open due to a cut wire. This circuit operates continuously in either mode of operation, "Armed" or "Disarmed", thereby providing early warning of a problem when in "Disarmed" mode. When in the "Armed" mode, an alarm activation would occur at the time the wire is cut open.
Referring now in particular to FIGS. 1 and 2, a first preferred embodiment of the present invention is illustrated and shall be described. The system of the invention is primarily designed to be utilized in conjunction with most alarm control panels. The control panel should be capable of monitoring a normally closed circuit and provide a filtered twelve volt direct current as well as having a battery back-up system. It should also provide a positive potential output when the system is in the "Armed" mode of operation.
The system of the invention is preferably designed to operate at 12 V.D.C. @ 100 MA. The negative potential from the main control panel is connected to wiring terminal block #1 of the system, while the positive potential is connected to the terminal block #2. The positive anode of diode D1 is connected to terminal block #2 positive potential (B+), and the negative cathode is connected to the input of the linear voltage regulator U1. The voltage input is also connected to a by-pass capacitor C2, having the cathode connected to negative potential ground. The positive voltage also supplies a positive potential to U2, U3, U4, U5, U6, U7, and further points as shall later be described.
Referring to the linear voltage regulator U1, the voltage adjust input is connected to resistor R6 which returns to the voltage output of U1. Resistor R1 is connected to the voltage adjust input which returns to terminal block J1, terminal #3, being the normally closed series loop circuit input. The return side of the loop circuit is connected to terminal #4 of J1, which is connected to negative potential, ground. Resistors R1 and R6 determine the minimum and maximum output voltage of U1. As designed and illustrated, the minimum output voltage of U1 is preferably 2.5 volts, which occurs when all of the zoned circuits are closed. The maximum voltage is preferably 10 volts, which occurs when all of the zoned circuits are open.
Each of the four zoned closed circuit devices utilized in the illustrated embodiment include a specific zone coding resistor connected in parallel to the normally closed contacts, those being the input and output of each zoned circuit. Each of the four zone resistors are of a calculated value so as to produce voltage outputs from 2.5 through 10.0 volts, in divisions of 0.5 volts, thereby providing a means of determining all four zoned circuit combinations, being sixteen (16). FIG. 5, a zone/voltage table, clearly illustrates this aspect of the preferred embodiment.
The voltage adjust input of U1 is connected to the positive anodes of two capacitors being C3 and C4, and the negative cathode of each capacitor is connected to ground. These capacitors filter transient signals in the loop circuits. The voltage output of U1 is connected to the input of the 2 nd operational amplifier U7, which circuit is described in greater detail below. The voltage output of U1 is connected to the positive anode of capacitor C1, while the negative cathode is connected to ground. The capacitor C1 provides filtering of the output voltage.
The voltage output of U1 is also connected to the inputs of both U2 and U3. The two integrated circuits are Dot Display Drivers, and each contains its own adjustable reference and accurate ten step voltage divider. These drivers are connected in a cascading circuit arrangement. U2 is designed to provide voltage detection and indication of 0.5 through 5.0 volts, in segments of 0.5 volts. The R-high and the R-low of both U2 and U3 are connected together where R-high and R-low are the ends of the divider chain. The reference voltage output is preferably 1.25 volts.
The R-high determines the voltage as produced from the 10 th comparator of U2 to be 5.0 volts as set by R4, which is connected from pin #6 and #7, #6 being the high voltage set and #7 being the reference out. R4 returns to pin #8 being the reference adjust, which is set at 1.25 volts by R5 and connected from pin #8 to ground, negative potential.
The second Dot Display Driver U3 is connected in the same manner, where R2 is connected to pins #6 and #7 and returns to pin #8, which sets the 10 th comparator at 10.0 volts. R3 is connected from pin #8 to ground, which sets the low input voltage of the 1 st comparator at 5.5 volts.
The combined two Dot Display Drivers provide the means to indicate input to output voltages in divisions of 0.5 volts, from 0.5 through 10.0 volts. The twenty comparators outputs of the combined U2 and U3 are now described. The outputs of U2, 0.5, 1.0, 1.5, 2.0 volts, pin #1,18,17,16 are not currently utilized in the illustrated example. The 2.5 volt output (pin #15) is connected to the cathode of a Light Emitting Diode (L.E.D.), D22, and the positive anode is connected to R8 and returns to positive potential. The L.E.D. D22 provides the indication of all zoned circuits to be normal and closed. It also indicates when the loop resistance and voltage is normal.
The 3.0 volt output (pin #14) is connected to the negative cathode of D7. Moreover, the positive anode is connected to R15 which returns to the input of the 4 th operational amplifier of U4, which represents zone A. This input is also connected to R16 and the cathode of C8, which are both connected to the positive potential Vcc. R15, R16 and C8 form an R.C. circuit, and where a negative signal is applied, it must be a continuous signal in excess of two seconds to cause a change of state of the operational amplifier output from a normal negative state to a positive state. Each of the four operational amplifiers inputs of U4 are essentially and preferably the same. The operation and processing of U4 shall be later described.
Each of the said four operational amplifiers represent the four zones of the loop circuit and are indicated by A, B, C, D. The 3.5 volt output (pin #13) is connected to the negative cathode of D4, the positive anode is connected to R13 which returns to the input of the 3 rd operational amplifier of U4, being representative of zone B. This input is also connected to R14 which returns to positive potential and is also connected to the cathode of C7. The anode is connected to positive potential Vcc.
The 4.0 volt output (pin #12) is connected to the cathode of D5, while the anode is connected to R13 which returns to the input of the 3 rd operational amplifier of U2, being zone B. The 4.0 volt output (pin #12) is also connected to the cathode of D6, while the anode is connected to R15 which returns to the input of 4 th input of U2, being representative of zone A.
The 4.5 volt output (pin #11) is connected to the cathode of D3, and the anode is connected to R11 which returns to the input of the 2 nd operational amplifier of U2, being zone C. The output (pin #11) is also connected to R7, which returns to Vcc and determines the Dot mode of operation.
The 5.0 volt output (pin #10) is connected to the cathode of D8, and the anode returns to R11 which returns to the input of the 2 nd operational amplifier of U4, being representative of zone C. This input is also connected to R12, which returns to Vcc, as well as being connected to the cathode of C6. The anode is connected to Vcc. The 5.0 volt output is also connected to the cathode of D9, and the anode is connected to R15 which returns to the input of the 4 th operational amplifier of U4, being representative of zone A. The voltage outputs of U3 provide output voltages in divisions of 0.5 volts, being 5.5 volts through 10.0 volts.
The 5.5 volt output (pin #1) is connected to the mode (pin #9) of U2, determining the Dot mode of operation. The 5.5 volt output is also connected to the cathode of D10, and the anode is connected to R11 which returns to the input of the 4 th operational amplifier of U4, being representative of zone C. The 5.5 volt output is also connected to the cathode of D11, and the anode is connected to R13 which returns to the input of the 3 rd operational amplifier of U4, being representative of zone B.
The 6.0 volt output (pin #18) is connected to the cathode of D12, and the anode is connected to R11 which returns to the input of the second operational amplifier of U4, being representative of zone C. The 6.0 volt output is also connected to the cathode of D13, and the anode is connected to R13 which returns to the input of the 3 rd operational amplifier, being representative of zone B. The 6.0 volt output is also connected to the cathode of D14, and the anode is connected to R15 which returns to the input of the 4 th operational amplifier, being representative of zone A.
The 6.5 volt output (pin #17) is connected to the cathode of D2, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D.
The 7.0 volt output (pin #16) is connected to the cathode of D15, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D. The 7.0 volt output is also connected to the cathode of D16, and the anode is connected to R15 which returns to the input of the 4 th operational amplifier, being representative of zone A.
The 7.5 volt output (pin #15) is connected to the cathode of D17, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D. The 7.5 volt output is also connected to the cathode of D18, and the anode is connected to R13 which returns to the input of the 3 rd operational amplifier, being representative of zone B.
The 8.0 volt output (pin #14) is connected to the cathode of D19, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D. The 8.0 volt output is also connected to the cathode of D20, and the anode is connected to R13 which returns to the input of the 3 rd operational amplifier, being representative of zone B. The 8.0 volt output is also connected to the cathode of D21, and the anode is connected to R15 which returns to the input of the 4 th operational amplifier, being representative of zone A.
The 8.5 volt output (pin #13) is connected to the cathode of D23, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D. The 8.5 volt output is also connected to the D24, and the anode is connected to R11 which returns to the input of the 2 nd operational amplifier, being representative of zone C.
The 9.0 volt output (pin #12) is connected to the cathode of D25, and the anode is connected to R9 which is connected to the input of the 1 st operational amplifier, being representative of zone D. The 9.0 volt output is also connected to the cathode of D26, and the anode is connected to R11 which returns to the input of the 4 th operational amplifier, being representative of zone C. The 9.0 volt output is also connected to the cathode of D27, and the anode is connected to R15 which returns to the input of the 4 th operational amplifier, being representative of zone A.
The 9.5 volt output (pin #11) is connected to the cathode of D28, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D. The 9.5 volt output is also connected to the cathode of D29, and the anode is connected to R11 which returns to the input of the 2nd operational amplifier, being representative of zone C. The 9.5 volt output is also connected to the cathode of D30, and the anode is connected to R13 which returns to the input of the 3 rd operational amplifier, being representative of zone B.
The 10.0 volt output (pin #10) is connected to the cathode of D31, and the anode is connected to R9 which returns to the input of the 1 st operational amplifier, being representative of zone D. The 10.0 volt output is also connected to the cathode of D32, and the anode is connected to R11 which returns to the input of the 2 nd operational amplifier, being representative of zone C. The 10.0 volt output is also connected to the cathode of D33, and the anode is connected to R13 which returns to the input of the 3 rd operational amplifier, being representative of zone B. The 10.0 volt output is also connected to the cathode of D34, and the anode is connected to R15 which returns to the input of the 4 th operational amplifier, being representative of zone A.
The operations of U2, U3 and U4 are now described in detail. The voltage output's of U2 and U3 in a normal condition, being off, produce a positive output. When any or all of the twenty output voltages become activated, they produce a negative potential at the corresponding outputs, thereby changing the output state from positive to negative. The outputs are connected to diodes which allow only negative potential to pass forward. Each of the diodes are connected to a particular zone #, being A, B, C or D inputs of U4. The design as illustrated provides a means to produce voltages of 0.5 through 10.00, in divisions of 0.5 volts. See FIG. 5, Zone/voltage table.
U4 is designed as an inverting comparator, containing four separate operational amplifiers. The first amplifier represents Zone D, while the second represents zone C, the third represents zone B, and the fourth represents zone A. The normal condition being off, the output state is negative potential. The negative inputs of the four operational amplifiers are normally a positive potential as provided by resistors R10, R12, R14, and R16. The voltage reference of the four comparators are determined by resistors, R17 and R18.
When a negative signal is received at any of the four input resistors, R9, R11, R13, and R15, it returns to the respective four R.C. circuits, designed at two seconds. Therefore, the applied negative potential must exceed two seconds to cause a change of state of any of the four outputs of U4.
The output of the 1 st comparator is connected to the anode of D35, and the cathode is connected to the control input, zone A of U5, being a quad bilateral switch utilized as a data selector. The control input is also connected to the cathode of C9, and the cathode is connected to ground. The control input is also connected to the anode of D43, and the cathode is connected to R19, which returns to ground. This determines the voltage applied to an amber L.E.D., indicating zone A.
The output of the 2 nd comparator is connected to the anode of D36, and the cathode is connected to the control input of zone B. The control input is connected to the cathode of C10, and the anode is connected to ground. The control input is also connected to the cathode of D44, and the anode is connected to R20, which returns to ground and determines the voltage to the amber LED, D44, which indicates zone B.
The output of the 3 rd comparator is connected to the anode of D37, and the cathode is connected to the control input of zone C. The control input is connected to the cathode of C11, and the anode is connected to ground. The control input is also connected to the anode of D45, and the cathode is connected to R21, which returns to ground and determines the voltage of the amber LED, D45, which indicates Zone C.
The output of the 4 th comparator is connected to the anode of D38, and the cathode is connected to the control input of zone D. The control input is connected to the cathode of C12, and the anode is connected to ground. The control input is also connected to the anode of D46, and the cathode is connected to R22, which returns to ground and determines the voltage to the amber LED, D46, which indicates Zone D.
Capacitors C9, C10, C11, and C12 provide filtering of voltage spikes in the input circuits of U5. The control input of U5, zone A, is connected to the cathode of D47, and the anode is connected to output A of U5. The A output is also connected to the anode of D51, and the cathode is connected to the input of R23, which returns to the + input of the 1 st operational amplifier of U7, utilized as a comparator. The control input B is connected to the cathode of D48, and the anode is connected to output of B, of U5, with the cathode being connected to the input of R23. The control input C is connected to the cathode of D49, and the cathode is connected to the output of C, of U5, with the anode being connected to the input of R23. The control input of D is connected to the cathode of D50, and the anode is connected to the output of D, of U5, with the anode being connected to the input of R23.
In describing the operations of U5, and U7, the 1 st operational amplifier of U7 is designed as a non-inverting comparator. The return of R23 is connected to the + input of the 1 st comparator. The input is also connected to the anode of C13, and the cathode is connected to ground. C13 provides filtering of the input of U5. The input is also connected to R24, and this returns to ground. R24 provides negative potential to the input. Therefore, the normal output state is negative potential, but when a positive potential is applied to the positive input, this changes the output to positive potential.
The positive input is also connected to the cathode of D56, and the cathode is connected to terminal #5 of J1, being the "Arm" and "Dis-Armed" mode of operation. Terminal #5 of J7 is also connected to the anode of D56, being an amber LED indicating mode of operation. The cathode is connected to R28, which returns to ground. R28 determines the voltage to D56. When in the "Armed" mode, a positive potential is applied to the positive input and causes the output to be positive potential. This output is connected to Input A, Input B, Input C, and Input D of U5 and thereby applies a positive potential to the output as determined by the control inputs.
The negative input of U7 is connected to R25, which returns to ground. The input is also connected to R26, which returns to Vcc. The resistors determine the voltage threshold of the positive input. The negative input is also connected to the negative inputs of the 3 rd and 4 th comparators of U7, which shall later be described.
When a positive potential from U4, zone A is received at the control input of zone A of U5, and when in the "Armed" mode of operation, it applies a positive potential to zone A output, which applies positive potential to the anode of D47. The cathode applies the positive potential to control of zone A, thereby latching on/in control zone A. The output of zone A is also connected to the anode of D51 with the cathode being connected to R23, which returns to the positive input of the 1 st comparator of U7 and applies a second positive potential to the positive input. Therefore, when the system is "Disarmed", and zone A of U5 has been latched-in, it still provides the second positive potential, via D51, which applies positive potential to the positive input of the 1 st comparator, which in turn applies the positive potential to the Input of zone A, for the latch remains on. In like manner, zones B, C, and D provide the same results of each zone. Accordingly, D48 and D51 process zone B, D49 and D54 process zone C, and D50 and D54 process zone D.
The positive input of the 1 st comparator of U7 is connected to S14, being a single pole single throw normally open switch having a spring return. The switch return is connected to R27, which returns to ground. The return is also connected to the anode of C14, and the cathode is connected to ground. S14 serves as a latch reset, once the system has been "Disarmed".
In describing the operations of U5 and U6, the U6, CD4066, is also a quad bilateral switch utilized as a data selector, as is U5. The Output, zone A of U5 is connected to the Control, zone A of U6, while the Output, zone B of U5 is connected to the Control, zone B, of U6. Likewise, the Output, zone C of U5 is connected to the Control, zone C, of U6, while the Output, Zone D of U5 is connected to the Control, zone D, of U6. When any of the four zoned Outputs of U5 become positive potential, this applies the positive potential to the corresponding zone Control(s) of U6, i.e. zones A, B, C, D.
The operations of U6 and programming switches, S1 through S12, are now described. All switches are preferably single pole single throw. S1 is connected to the Output, zone A of U6. The return is connected to the Output, zone D. Zone D is also connected to the + input of the 3 rd comparator U7, which shall later be described. S2 is connected to the Output, zone B of U6. The return is connected to the Output, zone D. S3 is connected to the Output, zone C of U6. The return is connected to the Output, zone D. S4 is connected to the Input, Zone A of U6. It is also connected to Vcc, and the return is connected to the Input , zone B. S5 is connected to Vcc, and returns to the Input, zone C, of U6. S6 is connected to Vcc, and returns to the Input, zone D, of U6. S7 is connected to the Input zone B, and returns to the Output zone A of U6. S8 is connected to the Input zone C, and returns to the Output zone A of U6. S9 is connected to the Input zone D, and returns to the Output zone A of U6. S10 is connected to the Input zone C, and returns to the Output zone B of U6. S11 is connected to the Input zone D, and returns to the Output zone B of U6. S12 is connected to the Input zone D, and returns to the Output zone C of U6. The programming and reading of selector switches shall later be described.
In the operations of U6, U7, K1, the Output, zone D of U6 is also connected to the positive input of the 3 rd comparator of U7. This input is also connected to R32, which returns to ground. R32 provides a negative potential to the positive input for normal off operation, where the output is negative potential. The negative input of the 3 rd comparator and the negative input of the 4 th comparator are connected together and returned to negative input of the 1 st comparator, thereby determining the threshold voltage of the positive inputs of the 3 rd and 4 th comparators.
The output of the 3 rd comparator is connected to the anode of C15, and the cathode is connected to the positive input of the 4 th comparator. The positive input of the 4 th comparator is also connected to R33, which returns to ground. C15 and R33 form an R.C. circuit of four seconds. In this manner, when a positive signal is applied at the positive input of the 3 rd comparator, this changes the output to a positive potential which is applied to the anode of C15, which in turn applies positive potential to the positive input of the 4 th comparator and which changes the output state to a positive potential for a time period of four seconds, and then returns to a negative state.
The positive input of the 3 rd comparator is also connected to S13, which returns to the positive input of the 4 th comparator. When S13 is in the off position, the four second time period is utilized. However, when S13 is in the off position and the positive potential is applied, as described above, it causes the output of the 4 th comparator to remain on, in a positive state, until the system has been "Disarmed" and reset.
The output of the 4 th comparator is connected to the relay coil of K1. The return of the coil is connected to Vcc. The anode of D59 is also connected to the output of the 4 th comparator, and the cathode is connected to Vcc. D59 eliminates voltage spikes across the coil of K1. The relay, K1, is normally on, engaged, when the single pole single throw contacts are closed. The relay contacts are connected to the wiring terminals 6, and 7 of J1, the normally closed output.
In the operation of the 2 nd comparator, U7, the output of zone D of U6 is also connected to the anode of D58, while the cathode is connected to R34, which returns to ground. R34 determines the voltage to D 58, being a Red L.E.D., providing indication of an alarm activation. The output of zone D of U6 is also connected to S15, which returns to the anode of D39, and the cathode is connected to the negative input of the 1 st comparator, U4. The return line of S15 is also connected to the anode of D40, and the cathode is connected to the negative input of the 2 nd comparator of U4. The return side of S15 is also connected to the anode of D41, and the cathode is connected to the negative input of the 3 rd comparator. The return is also connected to the anode of D42, and the cathode is connected to the negative input of the 4 th comparator of U4.
When an alarm activation occurs, as indicated by D58 Red L.E.D., a positive potential is applied to the anodes of D39, D40, D41 and D42, and passes forward through the said four diodes, thereby applying a positive potential to the negative inputs of the four comparators of U4, when S15 is on. Therefore, further activations from U2 and U3 will not be detected or registered at any of the four negative input's of U4. When any negative signal is produced via the outputs of U2 or U3, it must pass through the corresponding resistor, R9, R11, R13, or R15, and does not provide sufficient negative potential at the negative inputs of U4 to be detected. When S15 is off, this operation feature does not occur or apply. The programming and readings of selector switches, 1-12, are described in FIG. 4, Truth Table.
Referring to FIG. 8, diagram 1 thereof can be compared to diagram 1 of FIG. 3. As can be seen, the conventional wiring arrangement of FIG. 8 requires four separate circuits to the four zones while the arrangement of the present invention requires only one circuit to cover the four zones. Likewise, diagram 2 of FIG. 8 compares to diagram 3 of FIG. 3. It should be noted that the two devices of zone A in diagram 2 of FIG. 8 would require a latch/hold device to cause the circuit to remain an open circuit once activated. Moreover, the conventional wiring arrangement of diagram 2 of FIG. 8 also requires four separate circuits to cover the four zones unlike the present invention.
As can be seen from the above, the present invention provides several distinct advantages. It greatly reduces installation time and cost of present zoned system. The system also reduces servicing time since the system identifies the problem. Another distinct advantage is that the system provides a means of programming any and all possible switching circuit arrangements of the four zoned circuits. When two or more utilized devices are programmed to cause alarm activation, both devices need not be activated simultaneously to cause alarm activation. Therefore, separate latch-in devices are not required for each utilized zoned device in the present invention. Present zoned control panels would require physical rewiring of the utilized devices in the zoned circuit.
The system of the invention also provides a means of monitoring the closed loop circuit even when any or all circuits are open. Only when the closed loop circuit is cut open, a separate light emitting diode indicates a line cut. This design allows continuous twenty-four hour monitoring, and when the system is off, i.e. disarmed, it provides an indication of a problem prior to arming the system. Yet another distinct advantage of the present invention is that it provides a means to easily program or re-program any desired switching arrangements by means of twelve single pole, single throw selector switches, located internally within the system control panel. If or when any of the utilized devices become inoperable, such as in a state of open circuit, and service is required, the particular device may be by-passed by means of re-programming via the selector switches. This allows the system to be "Armed" to provide detection of all utilized devices with the exception of the defective by-passed device or devices. Thus, the system may be utilized until service can be done.
The foregoing description and the illustrative embodiments of the present invention have been described in detail in varying modifications and alternate embodiments. It should be understood, however, that the foregoing description of the present invention is exemplary only, and that the scope of the present invention is to be limited to the claims as interpreted in view of the prior art. Moreover, the invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein. | An apparatus is disclosed for use in a multi-zone alarm system having a single-pair wire alarm loop and programmable switching circuit arrangements. The apparatus includes a current source serially connected to the single-pair wire loop and selectively operative to provide a predetermined current signal in the loop. A plurality of zone sensing devices are arranged in a normally closed series circuit along the single-pair wire loop. Each of the zone sensing devices is adapted for generating coded voltage changes and alarm activation caused by an open circuit created therein. An element is provided for indicating the condition of each of the zone sensing devices, while a mechanism is provided for selectively arming and disarming the zone sensing devices. A circuit arrangement is provided for indicating an open circuit in the single-pair wire loop unrelated to the condition of the zone sensing devices, while another circuit is operative in response to the zone sensing devices to provide a signal indication of the zone in which alarm activation has occurred. Finally, a circuit mechanism is provided for continuously monitoring all circuit conditions of the apparatus in both the armed and disarmed operative conditions. | 6 |
This invention relates to urea-containing pelletized feeds for ruminant animals and the production of such pelletized feeds. More particularly, this invention is directed to increasing the efficiency of production including the rate of production of such feeds, increasing the nonprotein nitrogen content of such feeds and increasing the nonprotein nitrogen ("NPN") content of such feeds while improving or maintaining the flowability of such feeds when the feeds are subjected to material handling conditions, as when they are subjected to gravitational flow.
BACKGROUND
A ruminant animal's nutritional requirements generally are provided by forages, grains and other known feed stuffs. Pelleted feed supplements, however, are commonly used to provide nutritional fortification to the diets of ruminant animals, especially beef cattle in feedlots. These feed supplements generally have an organic component and inorganic component, each of which may form about one half, on a weight basis, of the feed supplement. The primary purpose of the feed supplement is to provide the animal with proteins, vitamins and minerals. The inorganic portion of the feed supplement frequently provides the animal with minerals and the organic portion frequently provides the animal with proteins. Ruminant animals have the capability to utilize NPN as a source of protein by virtue of bacterial conversion of NPN to protein in the stomach of the ruminant. NPN is inexpensive relative to using an organic protein source. Urea is commonly used as a source of NPN in pelleted supplements for ruminants.
When pelleted supplements containing urea are stored in vertical bins, however, it is often difficult to remove the supplements from the bin via gravitational flow. Urea-containing supplements tend to "hang-up" in the bin rather than flow freely. Precise mechanisms responsible for this problem are not well understood, but may be related to the hygroscopic nature of urea. A broad variety of measures have been used by both supplement manufacturers and supplement users to attempt to overcome this problem. These measures include minimizing steam addition during pelleting, dusting pellets with a fine, dry powder of calcium carbonate and installation of mechanical agitation equipment in the storage bins.
Ruminants such as feedlot cattle require a relatively high level of mineral supplementation in their diets. Hence, pelleted supplements tend to contain a high level of inorganic, particulate ingredients such as calcium carbonate and sodium chloride. These particulate inorganic materials constitute substantially all of the inorganic component of the feed and include mineral ingredients. Pelleted supplements also may include particulates such as urea in the organic portion of the feed. The latter mineral and urea particulates are abrasive and cause a high degree of resistance through a pelletization die. This resistance causes wear on manufacturing equipment and relatively poor production rates.
It is desirable to provide a method of increasing the efficiency and the rate production of pelletized feeds for ruminant animals, especially feeds which include a large portion of abrasive particulates such as urea and minerals such as calcium carbonate and sodium chloride.
It is desirable to provide a pelletized feed with an increased NPN content utilizing urea and a method for providing such a feed with an increased NPN content.
It also is desirable to provide a pelletized feed which includes urea and a method for improving the flowability of urea-containing pelletized feed.
SUMMARY OF THE INVENTION
The invention provides a method for increasing efficiency of production and the rate of the production of pelletized dry feed comprising abrasive particulates such as particulate urea and particulate inorganic materials, such as particulate minerals. In this aspect of the invention, the method comprises mixing aqueous ammonium polyphosphate with a dry feed blend which blend includes the abrasive particulates prior to the pelletization of the dry feed blend. The ammonium polyphosphate is mixed with the blend in an amount effective for providing an increase of the rate of production of pelletized feed at least about 3% relative to the production of a feed containing the same amounts of urea and inorganic materials without using ammonium polyphospate. In an important aspect, the invention is effective for increasing production rate of pelletized feed at least about 3% in a feed which has about from about 35 to about 65 weight percent urea and mineral particulate materials, based upon the weight of a prepelletized feed blend. In another important aspect, the ammonium polyphospate is mixed with the dry feed prior to pelletization such that the prepelletized feed contains at least about 0.3 weight percent ammonium polyphosphate. In another important aspect, sufficient ammonium polyphosphate and urea are mixed with the prepelletized feed to provide at least about 6.4 weight percent NPN in the pelletized feed and the amount of ammonium polyphosphate is effective for providing an increase in the rate of production of at least about 3%.
The invention in another aspect also provides a method for increasing the NPN content of a pelletized dry feed by balancing the urea and ammonium polyphospate content of the feed such that the pelletized feed has NPN content of at least about 5.6 weight percent and the pelletized feed of the invention has improved gravitational flowability compared to a pelletized feed without ammonium polyphosphate with the same NPN content. In an important aspect, the method comprises mixing ammonium polyphospate and urea with a feed blend to provide a pelletized dry feed having an NPN content of at least about 6.4 weight percent where the ammonium polyphosphate is in an amount effective for providing the pelletized feed with improved flowability compared to a pelletized feed without ammonium polyphosphate with the same NPN content.
In yet another aspect, the invention provides a pelletized dry feed comprising ammonium polyphosphate and urea in amounts effective for providing the pelletized feed with an NPN content of at least about 5.6 weight percent, and in an important aspect at least about 6.4 weight percent, the pelletized feed of the invention having improved gravitational flowability compared to a pelletized feed without ammonium polyphosphate with the same NPN content. In an important aspect the prepelletized feed has at least about 0.6 to about 2.4 weight percent ammonium polyphosphate, based upon the weight of the prepelletized feed blend including ammonium polyphosphate, with the remainder of the NPN being supplied by urea.
The invention also contemplates a pelletized dry feed with a high NPN content of at least about 8.0 up to about 11.5 or more weight percent where the prepelletized feed blend comprises urea and at least about 0.6 weight percent ammonium polyphosphate, the urea and ammonium polyphosphate being effective for providing the nonprotein nitrogen content of the feed.
Further, the invention provides a method for improving the flowability of a pelletized urea-containing feed, the method comprising adding ammonium polyphosphate into the dry feed prior to pelletization in an amount effective for improving the gravitational flowability of the pelletized feed containing the same relative amount of urea, but without ammonium polyphosphate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Definitions
Percentage of NPN means percentage of nonprotein nitrogen and is related to protein equivalents in that approximately 16.0 weight percent of protein is nitrogen. Hence, to get the protein equivalents from the weight percent NPN, multiply weight percent NPN by 6.25. Conversely, if the protein equivalent number is 40, the NPN weight percent is obtained by dividing 40 by 6.25 to indicate a NPN weight percent of 6.4.
Flowability means flowability under field material handling conditions using gravity. In the field, feed is moved from container to container using gravity. Hence, material handling using the invention and gravity to move pelletized feed is compared to material handling using gravity without the invention.
The percentage of ingredients in the prepelletized feed blend and the pelletized feed are assumed to be about the same. For clarity and consistency with the examples, this specification will sometimes refer to a weight percent based upon the weight of the prepelletized feed, but this percentage should be the same or very close to the percentage amount for the same ingredient in the pelletized feed.
Preferred Embodiments
This invention has several aspects. The pelletized dry feed supplement has an organic portion and an inorganic portion. The pelletized dry feed supplement is made by mixing aqueous ammonium polyphosphate and a dry feed blend which includes feed grade urea. Prior to the mixing of aqueous ammonium polyphosphate, the dry feed blend generally does not have more than about 15 weight percent moisture, and preferably does not have more than about 10 to 13 weight percent moisture, based upon the weight of the "dry" feed. Generally the feed blend has from about 35 to about 65 weight percent abrasive particulates which include urea and a particulate mineral portion. These particulates make pelletization through a pelletization die difficult. In one aspect of the invention aqueous ammonium polyphospate is mixed into the dry feed blend in amount sufficient to provide a prepelletized feed blend with at least about 0.3 weight percent ammonium polyphosphate based upon the weight of the feed blend which includes the ammonium polyphosphate to increase the rate of production of pelletized feed at least 3%. The amount of ammonium polyphosphate mixed with the feed blend is a function of the ingredients in the blend, especially the amount of particulate inorganic minerals and urea in the blend. The particle size of these abrasive particles vary from powder up to about 1000 microns. Because these materials tend to make extrusion of the pellets difficult, sufficient ammonium polyphosphate should be added to the dry feed blend in an amount effective for increasing the rate of production at least 3%. In an important aspect, sufficient aqueous ammonium polyphosphate is mixed into the feed blend to provide the prepelletized feed blend with from about 0.6 to about 2.4 weight percent ammonium polyphosphate, based upon the total weight of the feed blend, including the aqueous ammonium polyphosphate. This is to provide an increase in the rate of production of the pelletized feed, even with prepelletized feed blends having a abrasive particulate contents as high as 65 weight percent, based upon the total weight of the feed blend including the aqueous ammonium polyphosphate.
The dry feed blend has an organic portion which includes:
1. Grains and grain byproducts such as corn, sorghum, wheat, grain screenings, wheat middling, distillers grains, rice bran, and corn gluten feed;
2. Urea as a NPN source;
3. Plant protein products, such as soybean meal, cottonseed meal, sunflower meal, peanut meal, and corn gluten meal;
4. Animal protein products, such as meat and bone meal, blood meal, and feather meal;
5. Roughage products, such as oat hulls, cottonseed hulls and soybean hulls;
6. Animal fat;
7. Vegetable oils; and
8. Vitamin supplements.
The dry feed also has an inorganic portion, such as calcium carbonate, magnesium carbonate, potassium chloride, copper sulfate, zinc oxide, zinc sulfate, copper chloride, iron oxide, iron sulfate, manganous oxide, cobalt carbonate, ammonium sulfate, calcium sulfate, monocalcium phosphate, dicalcium phosphate, sodium chloride, and magnesium oxide.
To build NPN content, the feed prepelletized blend will have at least one weight percent feed grade urea up to about 20 weight percent urea based upon the weight of the blend which includes ammonium polyphosphate. Ammonium polyphosphate and urea may be balanced in the feed, as will be discussed to provide an NPN content in the pelletized feed as high as 8 to 11.5 weight percent and above.
In another aspect the invention provides a method for increasing the NPN of a pelletized dry feed by balancing the urea and ammonium polyphospate content of the feed such that the NPN content of the pelletized feed is at least about 5.6 weight percent and the pelletized feed of the invention has improved gravitational flowability compared to a pelletized feed without ammonium polyphosphate with the same NPN content. In an important aspect, the method comprises mixing ammonium polyphospate and urea into a dry feed to provide a pelletized dry feed having an NPN content of at least 6.4 weight percent where the ammonium polyphosphate is in an amount effective for providing the pelletized feed with improved gravitational flowability compared to a pelletized feed without ammonium polyphosphate with the same NPN content. In this aspect of the invention the amount of aqueous ammonium polyphosphate mixed with the dry feed blend is an amount effective to provide the feed blend with at least about 0.6 weight percent ammonium polyphosphate, based upon the weight of the prepelletized feed blend including ammonium polyphosphate. In an important aspect the prepelletized feed blend will have at least about 2.0 weight percent ammonium polyphosphate and at least about 11 weight percent urea to provide an NPN content of the pelletized feed of about 6.4 weight percent.
The pelletized feed blend is made by mixing the organic portion and inorganic portion including the urea and particulate minerals in a ribbon mixer to achieve homogeneous mixing such as after about one minute in a ribbon mixer. Thereafter the ammonium polyphosphate is sprayed into the blend as an aqueous solution which is commercially available as a solution with 59 weight percent ammonium phosphate and 41 weight percent water. Thereafter, the blend which includes the ammonium polyphosphate is mixed for about 3 to about 5 minutes and is conveyed to a conditioning chamber where steam is introduced into the chamber to achieve a feed or meal conditioning temperature of from about 100 to about 130° F. The temperature of the feed at the die should not exceed about 160° F. Then, the warmed feed is dropped into a pelletizing die and formed into pellets. Thereafter, the warm pellets drop directly from the pelletmill into a cooler and are cooled using ambient air to within 10 degrees Fahrenheit of ambient temperature. The cooled pellets are then discharged and conveyed to a storage bin for eventual use.
The pelletization die usually is a cylinder with a plurality of holes in its curved walls with one or more rollers pushing the feed through the holes in the curved walls. A blade nips the pellets as they exit the holes. A fuller description of known pelletization equipment appears in Feed Manufacturing Technology, American Feed Industry Association, Inc., Arlington, Va., Vol. IV 1994, Ch. 10, pp. 111-130, which is rewritten herein.
The following examples illustrate how to practice the invention and make the pelletized feed of the invention.
EXAMPLE 1
A nutrient constant formula and a standardized formula as shown below are pelletized according to the following procedure. Production data also is shown below. This data shows the significance of the presence of ammonium polyphosphate increasing the production of pelletized urea-containing feed supplement. The formulations were pelletized as follows:
1.) Mixing--
Scott Ribbon Mixer--1/4 Ton
Ingredients of each formula are hand scaled into weigh buggy and transferred to the mixer by elevator leg. The ammonium polyphosphate is sprayed onto the feed and the feed is mixed for five minutes.
2.) The mixed feed is conveyed by gravity into elevator leg and transferred to the pelletmill hopper.
3.) Pelletmill--
California Pelletmill--Century Model--50 HP
The pelletmill feeder meters the feed into the conditioner. The feed is mixed with steam to achieve the conditioning temperature. The warm feed falls out of the conditioner into the die chamber and is formed into pellets. The pelletmill die is 16 inch diameter, 10/64 pellet hole diameter, with a 2 inch effective thickness, 1/4 inch variable relief.
4.) Cooling--The pellets are transferred by a belt conveyor into a Wenger single pass horizontal cooler. The pellets are cooled by ambient air to within 10 deg F. of the ambient air temperature. The cooled pellets are belt conveyed to the bagging bin.
EXAMPLE 1
______________________________________ Nutrient-Constant Standardized Formula Formula Control APP** Control APP______________________________________Formulations Evaluated*Corn 18.05 15.55Wheat midds 60.79 61.54 61.38 61.38Soybean meal 3.53Urea 10 10 10 10Salt 6.25 6.75 6.75 6.75Calcium carbonate 15.51 16.84Potassium chloride 2.11 2.22 2.13 2.13Mono-dicalcium phosphate 1.81 0.15 1.69 1.69Ammonium polyphosphate 2.5 2.5Total 100 100 100 100Nutrient levelsProtein 41 41 41 42.34Crude fiber 5.54 5.32 5.69 5.63Crude fat 0.45 2.43 3.15 3.05Calcium 6.5 6.75 0.39 0.41Phosphorus 1 1 1 1.36NPN 4.6 4.85 4.6 4.85Production DataBatch size, lb 500 500 500 500Runtime, min 13.58 12.25 12.25 11.75Tons/hr 1.1 1.22 1.22 1.28Production temperatures***Meal 55 60 60 60Conditioned 115 113 120 114Hot pellet 160 163 159 145Die change 45 50 39 31Cool pellet 96 96 72 74Production dry mattersMeal 91 87.55 86.57 86.49Conditioned 87.5 86.93 84.72 83.82Cool pellet 89.88 90.04 87.28 86.77PDI**** 98.4 98.6 98 97.8Density 36.9 36.5 35.55 35.05______________________________________ *Formulations are weight percent **APP is ammonium polyphosphate with the percentage of ammonium polyphospate being the percent of a solution comprising 59 weight percent ammonium polyphosphate and 41 weight percent water. ***Degrees F ****Pellet Durability Index
EXAMPLE 2
The ingredients listed in Table A are conveyed from storage bins into a scale hopper located directly above a Hayes and Stoltz three ton ribbon mixer. The ingredients are individually weighed in the scale hopper to provide the weight percentages listed in Table A and are allowed to fall by gravity into the mixer. The dry ingredients are mixed for about 30 seconds to one minute, the ammonium polyphosphate is sprayed thereon and mixing is continued for 3-5 minutes to form a uniform blend. The uniform blend is placed in a surge hopper and then is conveyed to a pellet mill hopper. The uniform blend was metered from the pellet mill hopper into the conditioning chamber of a 250 horsepower California Pelletmill. Steam is introduced into the chamber to achieve a meal conditioning temperature of from about 100 to 130° F. This warmed meal was dropped into the die and formed into pellets.
The warm pellets drop directly from the pelletmill through an airlock into the California Pelletmill Cooler (Model 2400×2400) and are cooled using ambient air to within 10 degrees Fahrenheit of ambient temperature. Pellets are discharged when cooled and are transferred by elevator into a storage bin for eventual use. The pellets made according to the above procedure are gravitationally flowable.
TABLE A______________________________________Ingredients % Used______________________________________Feather meal 12.000Distillers grains 12.500Urea 11.94Salt 3.93Calcium carbonate 17.270Potassium chloride 50 5.84Sunflower meat 6.77Mono-dicalcium phosphate 1.55Ammonium polyphosphate 2.000Ammonium sulfate 5.000Zinc sulfate 0.096Mineral ad 3.000Trace mineral Premix 0.250Peanut meal 17.55Total 100.000______________________________________
TABLE B______________________________________ Nutrient Levels Amount______________________________________ Protein % 67.000 Fat % 2.25 Calcium % 7.850 Phosphorus % 0.930 Magnesium % 0.75 NPN % 6.7 Sulfur % 1.500 Potassium % 3.26 Dry matter % 94.63______________________________________
EXAMPLE 3
The ingredients in Table A below were pelletized as described in example 2 and provided a flowable pelletized product.
______________________________________Ingredients % Used______________________________________Rice bran - high fat 9.000Distillers grains 5.000Urea 22.950Salt 4.100Potassium chloride 50 1.15Sunflower meal 5.85Mag ox 54 1.88Mono-dicalcium phosphate 0.310Ammonium polyphosphate 1.000Ammonium sulfate 1.500Copper sulfate 0.050Trace mineral premix 1.52Peanut meal 21.89Calcium carbonate 23.81Total 100.000______________________________________Nutrient Levels Amount______________________________________Protein % 84.000Fat % 2.46Calcium % 9.600Phosphorus % 0.600Iodine MG/KG 12.62Manganese MG/KG 1,367.79Salt % 4.000Zinc MG/K 2529.880Copper MG/K 519.87Iron MG/K 94.84Magnesium % 1.500Cobalt MG/K 3.79NPN % 10.88Sulfur % 0.436Potassium % 1.000Dry matter % 95.66Sodium % 1.68Add Vit. A KIU/LB 0.000Add Vit. E LB 0.000______________________________________ | This invention is directed to increasing the efficiency of production including the rate of production of urea-containing pelletized feeds, increasing the nonprotein nitrogen content of such feeds and increasing the nonprotein nitrogen ("NPN") content of such feeds while improving or maintaining the gravitational flowability of such feeds when the feeds are subjected to material handling conditions, as when they are subjected to gravitational flow. | 0 |
RELATED APPLICATION AND TECHNICAL FIELD
[0001] This application is related to the following U.S. application, of common assignee, from which priority is claimed, and the contents of which are incorporated herein in their entirety by reference: “High Voltage CMOS H-Bridge Gate Drive Power Supplies,” U.S. Provisional Patent Application Ser. No. 60/661,754, filed Mar. 15, 2005.
[0002] This disclosure relates to power supplies for power amplifiers and, more particularly, to driving H-Bridge transistors at relatively high speed without components located off-chip.
BACKGROUND
[0003] Some types of power amplifiers such as pulse width modulated (PWM) amplifiers include a network of switching elements for controlling the directional flow of output current into a load. By outputting currents that alternate in direction, PWM amplifiers drive direct current (DC) and stepper motors for motion control applications in robotics, servomechanisms, printing devices, etc.
[0004] To provide currents with alternating flow directions, some PWM amplifiers implement four switching elements that provide two output currents with different flow directions. This circuitry, known as an “H-Bridge”, may include various types of electronic components (e.g., relays, transistors, etc.) to provide the four switching elements.
[0005] To control H-Bridge operations, the PWM amplifier produces a pulse train that controls the functioning of the electronic switching components. For example, an external signal provided to a PWM amplifier may control the duty cycle of the pulse train. To initiate current flow in one direction, the duty cycle of the pulse train is increased to one pair of switching elements while the duty cycle of a complementary pair of switching elements is reduced.
[0006] Conventional PWM amplifiers implemented in monolithic integrated circuits (ICs) typically implement n-channel transistors and are typically unable to independently provide appropriate signal levels for controlling H-Bridge operations. To attain the appropriate signal levels, such PWM amplifiers use transistors implemented as source followers to “pull-up” signal levels. These pull-up transistors are typically coupled using relatively large capacity capacitors, known as bootstrap capacitors. Due to their large storage capacity, these bootstrap capacitors are typically located external to the IC. By implementing pull-up transistors and bootstrap capacitors, design complexity and production cost increases.
SUMMARY OF THE DISCLOSURE
[0007] In accordance with an aspect of the disclosure, an apparatus includes an integrated circuit that includes low side power supply circuitry that provides an output voltage for H-bridge circuitry. The low side power supply circuitry includes one transistor that provides one current to the output of the low side power supply circuitry in response to the output voltage of the low side power supply circuitry dropping below a quiescent level. The low side power supply circuitry also includes a second transistor that controls the conduction state of a third transistor, based at least in part, upon the first transistor providing the first current to the output of the low side power supply circuitry. The third transistor provides a second current to the output of the low side power supply circuitry.
[0008] In accordance with another aspect of the disclosure, an apparatus that includes an integrated circuit that includes high side power supply circuitry that provides an output voltage for H-bridge circuitry. The high side power supply circuitry includes a transistor configured to draw a first current from the output of the high side power supply circuitry in response to the output voltage of the high side power supply circuitry exceeding a quiescent level. The high side power supply also includes a second transistor that controls the conduction state of a third transistor, based at least in part, upon the first transistor drawing the first current from the output of the high side power supply circuitry. The third transistor draws a second current from the output of the high side power supply circuitry.
[0009] In accordance with still another aspect of the disclosure, an apparatus includes an integrated circuit that includes low side power supply circuitry that provides an output voltage for H-bridge circuitry. The low side power supply circuitry includes a transistor that provides a first current to the output of the low side power supply circuitry in response to the output voltage of the low side power supply circuitry dropping below a quiescent level. The low side power supply also includes a second transistor that controls the conduction state of a third transistor, based at least in part, upon the first transistor providing the first current to the output of the low side power supply circuitry. The third transistor provides a second current to the output of the low side power supply circuitry. The integrated circuit also includes high side power supply circuitry that provides an output voltage for the H-bridge circuitry. The high side power supply circuitry includes a fourth transistor that draws a first current from the output of the high side power supply circuitry in response to the output voltage of the high side power supply circuitry exceeding a quiescent level. The high side power supply circuitry also includes a fifth transistor that controls the conduction state of a sixth transistor based, at least in part, upon the fourth transistor drawing the first current from the output of the high side power supply circuitry. The sixth transistor draws a second current from the output of the high side power supply circuitry.
[0010] In accordance with still another aspect of the disclosure, a method includes a transistor, sending a first current to an output of a low side power supply circuitry in response to the output voltage of the low side power supply circuitry dropping below a quiescent level. The low side power supply circuitry provides an output voltage for H-bridge circuitry. The method also includes a second transistor, sending a second current to the output of the low side power supply circuitry, based at least in part, upon the first transistor sending the first current to the output of the low side power supply circuitry. A third transistor controls the conduction state of the second transistor.
[0011] Additional advantages and aspects of the present disclosure will become readily apparent to those skilled in the art from the following detailed description, wherein embodiments of the present invention are shown and described, simply by way of illustration of the best mode contemplated for practicing the present invention. As will be described, the present disclosure is capable of other and different embodiments, and its several details are susceptible of modification in various obvious respects, all without departing from the spirit of the present disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as limitative.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a block diagram representing a pulse width modulation amplifier.
[0013] FIG. 2 is a block diagram representing a portion of the H-Bridge controller included in the PWM amplifier shown FIG. 1 .
[0014] FIG. 3 is one exemplary circuit used to implement the low side driver power supply shown in FIG. 2 .
[0015] FIG. 4 is one exemplary circuit used to implement the high side driver power supply shown in FIG. 2 .
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0016] FIG. 1 is a block diagram of a pulse width modulation (PWM) power amplifier 100 according to one embodiment. In this exemplary embodiment, PWM amplifier 100 includes Control Logic and PWM Generator Circuitry 102 , H-bridge Controller Circuitry 104 , and H-bridge Circuitry 106 that provides the output of the PWM amplifier.
[0017] PWM amplifier 100 may provide an output current that may alternate between two flow directions. For example, a current that flows in one direction to a load may be provided during one time period and another current that flows in an opposite direction may be provided during another time period. Control Logic and PWM Generator Circuitry 102 may be connected to a plurality of inputs 108 for receiving one or more input signals. For example, Control Logic and PWM Generator Circuitry 102 may receive one or more input signals, for defining output current limits, for timing, and/or for reference (e.g., a reference voltage signal) and/or protection (e.g., a short circuit alert signal).
[0018] Control Logic and PWM Generator Circuitry 102 may produce one or more control signals that may be provided to H-bridge Controller Circuitry 104 . For example, a PWM signal may be provided by Control Logic and PWM Generator Circuitry 102 to H-bridge Controller Circuitry 104 . Based on these control signals, H-bridge Controller Circuitry 104 may produce one or more signals for driving, e.g., switching elements included in H-bridge Circuitry 106 . For example, signals for biasing bipolar (e.g., bipolar junction transistors, etc.) and/or field-effect switching elements (e.g., field-effect transistors, complementary metal oxide semiconductor (CMOS) transistors, etc.) may be provided by H-bridge Controller Circuitry 104 . By providing appropriate driver signals to H-Bridge Circuitry 106 , PWM amplifier 100 may provide current signals that may flow in alternate directions to one or more loads connected to outputs 110 .
[0019] FIG. 2 is a detailed diagram of one embodiment of H-bridge Controller Circuitry 104 that implements complementary polarity metal-oxide semiconductor (MOS) transistors. H-bridge Controller Circuitry 104 may include power supply circuitry 202 , a high side driver 204 and a low side driver 206 . Low side driver 206 may deliver pulses to switching elements (e.g., N-channel power transistors) that may be located in H-bridge Circuitry 106 . In one design, pulses ranging between 0 volt to +20 volts may be provided to the low side switching elements over conductors 208 and 210 . Similarly, high side driver 204 may deliver pulses to complementary switching elements (e.g., P-channel transistors) that may be located in H-bridge stage 106 . To control these switching elements, pulses ranging between +60 volts and +40 volts may be provided over conductors 212 and 214 to the respective switching elements.
[0020] To provide power, e.g., a low side power supply 216 may be connected to low side driver 206 and a high side power supply 218 may be connected to high side driver 204 . Additionally, a source power supply 220 (e.g., +60 volts power supply) may be connected to high side driver 204 and power supplies 216 and 218 . Low side power supply 216 may approximately provide a +20 volt level to low side driver 206 and current as indicated by label I 1 . In a similar manner, high side power supply 218 may approximately provide a +40 volt level to high side driver 204 . However, as illustrated with label I 2 , power supply 218 may sink current. Additionally, power supply 218 may regulate a 20 volt level below the +60 volt level that may be provided by source power supply 220 . By regulating the voltage provided to high side driver 204 , the design may substantially prevent over-driving components in H-bridge Circuitry 106 . For example, by regulating the voltage, switching elements (e.g., P-channel transistors) in H-Bridge Circuitry 106 may be substantially prevented from exceeding a maximum gate breakdown voltage rating.
[0021] For demonstrative purposes, exemplary pulse trains 222 and 224 may be respectively provided by high side driver 204 and low side driver 206 to the appropriate switching elements in H-Bridge stage 106 . Pulse train 222 may be limited to voltage levels between +60 volts and +40 volts for controlling switching operations of e.g., P-channel power transistors, while pulse train 224 may provide approximately +20 volt pulses for controlling the switching operations of e.g., N-channel power transistors in H-bridge Circuitry 106 .
[0022] Conventional designs that implement N-channel transistors may include relatively large energy storage capacitors (i.e., bootstrap capacitors) that may be located external to the IC package containing the PWM amplifier. These additional components may increase production cost and design complexity. By implementing H-bridge controller circuitry that includes complementary metal oxide semiconductor (CMOS) technology, external energy storage components may be eliminated and production cost and design complexity may be reduced. By implementing power supplies with reduced output capacitance and relatively high operating speeds, H-bridge Controller Circuitry 104 (e.g., high side driver 204 , low side driver 206 , etc.) may operate at high speeds without external bypass capacitors. Additionally, by increasing the transfer conductance (i.e., transconductance) of power supplies 218 and 216 , transient driver currents may be compensated while reducing the need for external energy storage devices.
[0023] FIG. 3 is one circuitry embodiment of low side driver power supply 216 that includes components for increasing transconductance of the supply. To increase the transconductance of power supply 216 , three transistors 302 , 304 and 306 may be included in the power supply design. As described in detail below, due to the interaction of transistors 302 , 304 and 306 , output impedance of power supply 216 may be decreased. By increasing the transconductance of power supply 36 , additional decoupling by large energy storage devices (e.g., bypass capacitors) may not be needed.
[0024] To provide the +20 volts, power supply 216 may include a constant current source 308 that may be configured to develop a reference voltage V 1 across a resistor 310 . Resistor 310 may be connected to the source of a field-effect transistor (FET) 312 . Since the drain and gate of FET 312 are connected in this embodiment, the FET may function as an MOS diode for compensating threshold voltage variations in transistor 302 . A voltage V 2 may be present on the gate of FET 302 . Voltage V 2 may be approximately equivalent to voltage V 1 shifted by the gate-to-source voltage (V gs ) of FET 312 . Voltage V 2 may substantially cancel the variations in V T and G M of FET 302 .
[0025] A quiescent output voltage (V out ) of power supply 216 may be approximately equivalent to V 1 . However, slight variations in V out may be introduced due to different operating conditions and/or parameters respectively associated with FET 312 and FET 302 . In this embodiment, FET 302 may be configured as a common gate amplifier that may amplify the difference between voltage V out and V 2 . To perform this function, FET 304 may operate as a load device for FET 302 and drive the gate of FET 306 , which may be configured as a common source amplifier. In this exemplary embodiment, three FETs 314 , 316 and 318 may provide a voltage divider for biasing the gate of FET 304 . Power supply 216 may also include a FET 320 that may provide a relatively small bias current such that a small reverse output current or currents (e.g., due to leakage) may not substantially cause FET 302 to halt operations.
[0026] When a load variation may be experienced, FET 302 and/or FET 306 may conduct current to the output of the power supply. By providing this additional current, the output conductance of power supply 216 may be increased. In particular, when the current drawn by low side driver 206 increases, the output voltage of low side power supply 216 may be reduced below a quiescent level. For example, the output voltage may be reduced by an amount ΔV. Based on this reduction, FET 302 conducts as indicated by current label I 1 and a voltage V 3 present at the gate of FET 306 may become a negative level. Due to V 3 , FET 306 may be biased “on” and current may conduct from the source to the drain of FET 306 as indicated by current label I 2 . Since FETs 302 and 306 may provide current (i.e., current I 1 and I 2 ) to the output of power supply 216 , the output conductance of power supply 36 may increase due to the additional current contributions. As illustrated, currents I 1 and I 2 may combine to produce current I 3 . Currents I 1 and I 2 may be provided with a relatively low output impedance since the transconductance of FET 306 may be amplified by the voltage gains of FET 302 and FET 304 .
[0027] The increase in output conductance due to the contributions of FET 302 and 306 may be quantified from parameters associated with FETs 302 , 304 and 306 . As mentioned above, conductance may increase when the output voltage of power supply 216 is reduced by ΔV, in which:
ΔV=V 2 −V OUT . (1)
[0028] Using this voltage reduction ΔV:
Δ I 1 =ΔVgm 302 ; (2)
[0029] Where gm 302 may be the transconductance of FET 302 ;
Δ V 3 =ΔVgm 302 Rd 304 ; (3)
[0030] Where Rd 304 may be the drain resistance of FET 304 ;
Δ I 3 = Δ I 1 + Δ I 2 ; ( 4 ) G OUT = Δ I 3 Δ V OUT ; ( 5 )
[0031] Where G out is the output conductance of power supply 216 , and;
G OUT =gm 302 (1+ Rd 304 gm 306 ). (6)
[0032] Thus, as shown in equation (6), the output conductance of power supply 216 may be relatively large based on the transconductance of FET 302 and FET 306 and the drain resistance of FET 304 . By implementing FETs 302 , 304 and 306 , external large capacitors may not be needed for handling relatively fast changing driver transient load currents. Additionally, this embodiment of power supply 216 may dissipate less power and may need less circuit board space compared to conventional n-channel designs.
[0033] FIG. 4 is one circuitry embodiment of high side power supply 218 that provides a voltage level to high side driver 204 of H-bridge Controller Circuitry 104 . High side power supply 218 operates in a similar but complementary manner to low side power supply 216 . For example, three FETs may be incorporated into power supply 218 to compensate for transient load conditions. Some of these transient load conditions may cause the output voltage (e.g., +40 volts) of power supply 218 to increase above a desired level.
[0034] In this embodiment, FETs 402 , 404 and 406 may be included in power supply 218 to compensate for driver transient load conditions. This embodiment includes a constant current source 408 that may produce a voltage V 1 at a resistor 410 and a FET 412 . Voltage V 2 may be related to voltage V 1 by the gate-to-source voltage (V gs ) of FET 412 . As driver load conditions change, the output voltage may increase above a quiescent output level (e.g., +40 volts). By pulling the output V out to a higher voltage (i.e., above +40 volts), the voltage difference between V out and V 2 may bias FET 402 to conduct current as indicated by current label I 1 . FET 404 , which may function as a load device for FET 402 , may be biased by the voltage divider formed by FETs 414 and 416 . Due to the current I 1 , FET 406 may also be biased to conduct current as indicated with current label I 2 . By drawing currents I 1 and I 2 , the output voltage of power supply 218 may be reduced toward the quiescent level (e.g., +40 volts) of the supply. Similar to the power supply 216 , power supply 218 may include a FET 418 that may provide a standby current for FET 402 . Power supply 218 may also provide an output conductance as defined by equation (6), however, with reversed polarities.
[0035] While the power supply embodiments shown in FIG. 3 and FIG. 4 (i.e., power supply 216 and power supply 218 ) incorporate field-effect transistors to compensate for transient load conditions, other types of switch devices may be implemented exclusively or in combination with field-effect transistors for output voltage compensation. For example, bipolar junction transistor (e.g., PNP BJTs, NPN BJTs, etc.) may be implemented in some power supply embodiments (with or without one or more FETs) for providing appropriate voltage levels to high and/or low side drivers that may drive H-bridge circuitry.
[0036] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. Accordingly, other implementations are within the scope of the following claims. | An apparatus includes an integrated circuit that includes low side power supply circuitry that provides an output voltage for H-bridge circuitry. The low side power supply circuitry includes one transistor that provides one current to the output of the low side power supply circuitry in response to the output voltage of the low side power supply circuitry dropping below a quiescent level. The low side power supply circuitry also includes a second transistor that controls the conduction state of a third transistor, based at least in part, upon the first transistor providing the first current to the output of the low side power supply circuitry. The third transistor provides a second current to the output of the low side power supply circuitry. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to superabrasive tools such as rim wheels and wheel segments which comprise a superabrasive grain such as diamond or cubic boron nitride, (CBN).
Tools containing superabrasives are widely used for cutting extremely tough materials such as concrete for example. It is found however that the cost of such wheels is very high because the superabrasive component itself is very expensive. There is therefore considerable interest in the production of tools that are very effective and at the same time less expensive than tools in which the superabrasive component provides 100% of the abrasive content.
One such approach is illustrated in U.S. Pat. Nos. 5,152,810 and 4,944,773 in which part of the superabrasive component is replaced by a sol-gel alumina abrasive with surprisingly advantageous results and a significantly lowered cost.
The present invention provides a further advance in such technologies by providing the sol-gel alumina in a form conferring advantages in a highly efficient manner and adding new possibilities not described in the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial side view of a segment wheel of the type used for cutting concrete.
FIG. 2 is a perspective view of a wheel wherein the abrasive filaments are laid into the body of the segment.
FIG. 3 is a cross section of the segment of FIG. 2.
FIG. 4 is a cross section of a segment designed for attachment to a segment wheel.
FIG. 5 is a top view of the segment of FIG. 4.
FIG. 6 is a cross section of the segment shown in FIGS. 4 and 5 taken perpendicular to the cross section of FIG. 4.
DESCRIPTION OF THE INVENTION
The present invention provides an abrasive tool comprising a bond material having dispersed therein abrasive grains comprising at least one superabrasive component and filamentary particles of a microcrystalline alumina having an essentially uniform orientation.
The filamentary particles are essentially uniformly oriented by which is meant that their longitudinal axes are alligned such that the majority, and more preferably at least 75%, lie within a 120° arc and more preferably within an arc of about 60°.
The filamentary particles have a substantially uniform cross-sectional shape along an axis of symmetry and have an aspect ratio, (defined as the ratio between the length along the axis of symmetry and the greatest dimension perpendicular to that axis), of at least about 3:1 and preferably at least about 10:1. In some cases the filamentary particles can be much longer and even joined to form a continuous filament for at least the pre-use configuration of the tool. In the event a continuous filament is used to make the abrasive tool, the filament is laid in multiple tight folds with the sides of the folds essentially parallel in the desired direction of orientation of the filamentary particles. Such a continuous filament behaves essentially as a plurality of individual filaments, and for this reason is understood to fall within the essential scope of this invention.
The cross-sectional shape of the particles can be anything convenient but the most easily fabricated shapes are round or roughly square. Nevertheless the utility of the invention is not constrained by the shape of the cross-section.
The particles comprise a microcrystalline alpha alumina by which is meant that the individual crystallographically distinct domains or crystallites that make up the particles have an average diameter, (as measured by the average length of an intercept line drawn across a cross-section of the particle), of less than about 10 microns and preferably less than about one micron. The particle can contain other components such as phases comprising magnesia, zirconia, spinels, and rare earth metal oxides but is comprised of at least about 60% by weight, and more preferably at least 90% by weight, of alpha alumina. The density of the particles should be at least about 90%, and preferably at least 95% of the theoretical density for the composition. The most preferred particles have a hardness of at least 18 and more preferably at least 20 GPa.
It is often desirable that the filamentary particles contain other components modifying their abrasive properties. For example finely divided abrasive particles, such as diamond, CBN, tungsten carbide and the like, can be incorporated. Other particulate matter that can be incorporated might include high temperature-stable lubricants such as boron nitride (hexagonal form), molybdenum sulfide and graphite, grinding aids such as metallic tin and other fillers. Such additions are preferably chosen to ensure that their quantity and physical properties do not excessively reduce the hardness and strength that characterize the unmodified sol-gel alumina filamentary particles.
Such particles are made by a sol-gel process in which a sol of an alpha alumina precursor is gelled, usually by addition of an acid, dried, then fired. The size of the crystallites in the particle can be reduced by addition of a material effective to nucleate the crystallization of the alpha alumina from the precursor phase. Such materials are usually isostructural with the alpha alumina phase that is being formed with lattice parameters that as close as possible to those of alpha alumina itself. Alternatively the crystallite size can be limited by the use of pinning agents that restrain the growth process during the firing to form alpha alumina. Included among patents teaching suitable methods of making the filamentary particles are U.S. Pat. Nos. 4,314,827; 4,632,364; 4,744,802; 4,770,671; 4,881,951; 4,954,462; 4,964,883; 5,053,369; 5,076,815; 5,114,891; 5,139,978; European Application 408,771 and PCT Application 92/01646.
The particles can be made in any convenient manner but the most accessible route is through extrusion. In such a process the alpha precursor is extruded as a gel and then dried and fired to form the filaments. One suitable apparatus for producing such filaments is described in U.S. Pat. No. 5,090,968. It is also possible to extude and dry the filaments to a point at which they can conveniently be handled, incorporate them in the tool as it is formed and fire them in situ in the abrasive tool.
The orientation of the filamentary particles in the tool is particularly important in determining the types of properties that the tool will have. In one preferred embodiment the filamentary particles will be oriented such that they are alligned perpendicular to the abrading surface of the tool or at an angle less than about 60° to such surface. Often it is more advantageous to have the particles angled to the line perpendicular to the abrading surface providing the direction in which the tool moves against the workpiece is constant as would be the case if the tool were located at the rim of a cutting wheel. In this case the particles act as abrasives, significantly augmenting the cutting action of the wheel and permitting the use of less of the superabrasive component while sacrificing little of the cutting performance. It is particularly advantageous to provide that the filamentary particles are radially oriented and are located at the edges of a cutting wheel. This may be within the matrix of the tool or bonded into grooves cut in the side of the tool to accomodate the particles and a bond to locate them securely in such grooves.
Another orientation that is particularly useful, especially in wheels designed for cutting as for example a concrete cutting segmental wheel, has the axis of symmetry of the filaments essentially parallel to the cutting surface but located at the edges thereof. Conventional concrete cutting wheels tend to wear at the edges such that the width of the cut made will decrease as the wheel wears. Filamentary particles lying parallel to the cutting surface will provide even wear properties, inhibit segment erosion at the edges, and keep the cutting surface square. In such situations the filamentary particles are acting to reduce wear rather than as abrasives in themselves.
The tool itself can have any convenient form. A common shape is that of a wheel with the abrasive located at least at the periphery. Because of the cost of the superabrasive and because the wheels are conventionally used in situations where the wheel is under great stress, it is common to use a solid metal plate as the core portion of the wheel with the abrasive located at the rim, often in the form of segments attached to the core portion. The bond in which the abrasive is held in such cases is commonly a metal. The means of attachment is not critical providing it affords a strong, permanent attachment to the core portion. Suitable means include welding, brazing and sintering.
Another application in which the term "tool" refers to a segment rather than a structure into which the segment is or may be incorporated, is a saw such as a gang saw where the segments are attached to a metal blade to provide the cutting edges of the teeth of the saw. Still another example of a suitable tool would include the abrading surfaces of a Blanchard grinder.
Notwithstanding the above, the tools of the invention can include structures in which the abrasive is held in resinous or vitreous bonds.
DESCRIPTION OF PREFERRED EMBODIMENTS
The invention is now described in more detail with reference to the attached Drawings which are for the purpose of illustration only and are intended to imply any necessary limitations on the essential scope of the invention.
FIG. 1 is a partial side view of a segment wheel of the type used for cutting concrete. The core portion, 1, is of solid metal and segments, 2, are attached to the edge to form the cutting portion of the wheel. Grooves, 3, are cut or pressed into the side of the segments at an angle of about 45° to the radial direction and abrasive filaments are laid in the grooves and bonded to the segment by a metal bond. The body of the segment comprises diamond grains with aa appropriate particle size bonded by a metal bond.
FIG. 2 is a perspective view of a portion of a similar wheel to that shown in FIG. 1 except that the abrasive filaments are laid into the body of the segment as it is formed. This may be done by laying the filaments in individually but more conveniently the filament can be laid in tight serpentine folds as the segment is formed such that the grinding surface shows one set of folds each of which, on grinding, is worn down to expose two filament ends. FIG. 2 shows the segment in this configuration with the ends, 5, exposed on the cutting surface.
FIG. 3 is cross-section of the segment of FIG. 2 before the tops of the folds, 6, have been ground down to expose two filament ends.
FIG. 4 is a cross-section of a segment designed for attachment to a segment wheel as in FIGS. 1-3, wherein the filamentary abrasive, 7, is laid in tight fanfolds parallel to the grinding surface.
FIG. 5 is a top view of the segment of FIG. 4 after a period of wear to expose the filamentary abrasive particle, 7, laid parallel to the sides of the segment and adjacent the edges.
FIG. 6 is a cross-section of the segment shown in FIGS. 4 and 5 taken perpendicular to the cross-section of FIG. 4. The section is of a used wheel showing in exaggerated form that the filamentary particles, 7, cause the segment to wear to a U-shape and thus maintain its width of cut rather than becoming rounded in profile.
Other configurations with potential advantages can be devised combining the abrasive power of superabrasives and the particular structural advantages that flow from the use of the filamentary particles. These include for example forming the filamentary abrasive into an interlaced ring rather in the manner a ball of string may be wound with preferably a more flattened profile and then forcing a shapeable mixture of bond plus superabrasive to fill the interstices in the interlaced ring and then curing, firing or otherwise causing the bond material to become rigid in the form of an abrasive tool such as a wheel.
Such a structure could be given particular advantages by causing the dimensions of the interstices to be of such a size as to entrap grains of superabrasive and thus present them in a very rigid retaining structure to the surface to be ground or cut. | Superabrasive tools incorporating into the structure filamentary particles formed from a microcrystalline alumina confer significant advantages which depend on the orientation of the particles. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention pertains generally to continuous wave modulation, and more particularly relates to a reduced complexity tracking algorithm for the symbol timing synchronization of a continuous phase modulation (CPM) input data signal using a Viterbi algorithm for demodulation.
[0003] Continuous phase modulation (CPM) is a modulation format which generates a constant envelope signal and which possesses advantageous spectral properties. CPM has found utility in systems where it is desirable to use a constant envelope modulation, such as where high power nonlinear amplifiers are used. The constant envelope constraint introduces memory at the transmitter, effectively making a CPM signal more difficult to detect. Typically a Viterbi algorithm is used to perform sequence detection on the received symbol sequence. In order to compute the proper branch metric signals required in the Viterbi algorithm, the receiver must have an accurate estimate of the phase of the transmitter's symbol clock signal with respect to the received signal. This is known as symbol timing synchronization. The present invention describes a reduced complexity-tracking algorithm for the symbol timing synchronization of a CPM modulated signal where the Viterbi algorithm is used for demodulation.
[0004] Trellis decoders or demodulators are frequently used to demodulate signals modulated by continuous phase modulation (CPM). In the context of the present invention, coding/decoding and modulation/demodulation are analogous, and may be viewed as corresponding. CPM modulation has an advantage of providing a signal having substantially constant power, which is a marked advantage when transmitting the modulated signals over a nonlinear channel, as the constant power tends to reduce the generation in such a channel of unwanted distortion products which obscure the signals. A further advantage of CPM modulation is that the bandwidth of the transmitted signal is easily maintained, and the frequency spectrum exhibits low sidelobes, which is advantageous for situations in which a plurality of signals traverse a channel, as the signal spectrum for one of the signals traversing the channel has little frequency overlap with the signal next adjacent in frequency. In other words, the channels may be closer together in frequency.
[0005] CPM modulation is performed, in general, by converting the information or signal to m-ary quantized form, if not already in the desired form. For the simple case in which m=2, the signal is converted into binary form. The m-ary signal is applied to a shift register array having a particular length. As the signal bits are applied to the input end of the shift register array, the previously-applied signals are clocked and propagate through the shift register array, altering the states of the registers in succession. A combinatorial or functional logic arrangement is coupled to the output of each register of the array, and applies some function to the combination of register logic states. The applied function results in one or more output signals, which depend upon the combinatorial function, and also depend upon the current state of each register in the array. The current state of each register in the array in turn depends upon the history of the input signal.
[0006] The demodulation of a signal modulated in the above-described fashion can be accomplished by a trellis demodulator. The “trellis” represents, by “nodes”, the possible states of the registers of the modulator, and by lines joining the nodes, the possible paths by which transitions between states can be made. The trellis demodulator is often implemented as a Viterbi algorithm which performs sequence detection on the received symbol sequence. Demodulation using a Viterbi algorithm requires an accurate estimate of the phase of the transmitter's symbol clock signal with respect to the received signal. The process of obtaining an accurate estimate of the phase of the transmitter's symbol clock signal with respect to the received signal is known as symbol timing synchronization.
SUMMARY OF THE INVENTION
[0007] It is therefore an object of the present invention to provide a method of and apparatus for accurately estimating the timing of a transmitter's symbol clock signal with respect to a received signal.
[0008] It is another object of the present invention to realize a new symbol epoch tracking circuit for CPM receivers which overcomes the shortcomings of prior art conventional CPM receivers.
[0009] To that end, a symbol epoch tracking circuit performs symbol epoch tracking with minimal extra computation for a Viterbi decoder using a Viterbi algorithm and with excellent tracking performance.
[0010] The symbol epoch tracking circuit is implemented in a CPM receiver, and could also be implemented as a software defined process for use in any CPM demodulator employing a Viterbi algorithm for accurate data detection.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a simplified block diagram of a maximum likelihood symbol timing estimator which functions in accordance with the teachings of the present invention.
[0012] [0012]FIG. 2 is a simplified block diagram of a maximum likelihood symbol timing estimator of reduced complexity wherein a summation term is implemented as a lookup table.
[0013] [0013]FIG. 3 is a simplified block diagram of a maximum likelihood phase tracking synchronizer demodulator which includes a Viterbi decoder.
DETAILED DESCRIPTION OF THE INVENTION
[0014] A maximum likelihood estimator for the transmitted symbol timing epoch can be derived using maximum likelihood theory.
[0015] An appropriate likelihood function L(t, θ, τ, {overscore (d)}) for estimating the symbol timing epoch in a CPM demodulator is defined by equation (1):
L ( t , θ , τ , d ) = C exp { - 1 N o ∫ T o ( y ( t ) - s ( t , θ , τ , d ) ) 2 t } ( 1 )
[0016] where N 0 is the noise power, T 0 is the observation interval, y(t) is the received signal, C is a constant responsive to the amplitude of the received signal, and s(t, θτ, {overscore (d)}) is the transmitted signal. The parameters of the transmitted signals are θ, the carrier phase, τ, the symbol timing reference, and {overscore (d)}, the transmitted data sequence. {overscore (d)} is a vector and is referred to herein as d or {overscore (d)}. Taking logarithms and expanding the squared term in equation (1) gives the log-likelihood function as set forth in equation (2):
l ( t , θ , τ , d _ ) = ln ( C ) - 1 N o ∫ T o ( s ( t , θ , τ , d ) ) 2 + ( y ( t ) ) 2 - 2 y ( t ) s ( t , θ , τ , d ) t ( 2 )
[0017] The constant first term of equation (2) and the second term within the integral of equation (2) are independent of the parameter τ and may be dropped. For a constant envelope scheme such as CPM, the first term within the integral of equation (2) is also independent of the carrier phase reference θ. The equivalent log-likelihood function to be maximized is therefore given by equation (3):
l ( t , θ , τ , d ) = 1 N o ∫ T o 2 y ( t ) s ( t , θ , τ , d ) t ( 3 )
[0018] A necessary condition for a maximum of the equivalent log-likelihood function of equation (3) is that the derivative be zero at the maximum. Differentiating equation (3) with respect to the symbol timing reference, τ, and setting the result equal to zero, gives likelihood equation (4) for the estimation of the symbol timing epoch.
0 = 2 N o ∫ T o y ( t ) ∂ s ( t , θ , τ , d _ ) ∂ τ t ( 4 )
[0019] The transmitted signal in a CPM arrangement can be expressed as s(t, θ, τ, d) in equation (5):
s ( t , θ , τ , d ) = Re [ ( 2 E T ) 1 / 2 exp ( j ( ω o ( t + τ ) + θ + π ( ∑ i = - ∞ n - L d i h ) + 2 π ∑ i = n - L + 1 n d i hq ( t - iT + τ ) ) ) ] ( 5 )
[0020] where {overscore (d)} is the data vector, E is the transmit energy, T is the symbol period, ω 0 is the carrier frequency, and {overscore (d)}=(d_, d n−2 , d n−1 , d n ) is the transmit information or data sequence. In equation (5), the parameter q(t−iT+τ) is the phase pulse, L is the duration of the phase pulse, and h is the modulation index. Substituting the definition of the transmitted signal of equation (5) into the partial derivative of equation (4) one obtains equation (6):
∂ s ( t , θ , τ , d _ ) ∂ τ = Re [ j ( 2 E T ) 1 / 2 2 π ∑ i = n - L + 1 n d i h ∂ q ( t - iT + τ ) ∂ τ exp ( j ( ω o ( t + τ ) + θ + π ( ∑ i = - ∞ n - L d i h ) + 2 π ∑ i = n - L + 1 n d i hq ( t - iT + τ ) ) ) ] ( 6 )
[0021] Ignoring the constants, the likelihood equation associated with equation (6) is equation (7):
0 = ∫ T o Re [ j y ( t ) ∑ i = n - L + 1 n d i ∂ q ( t - iT + τ ) ∂ τ exp ( j ( ω o ( t + τ ) + θ + π ( ∑ i = - ∞ n - L d i h ) + 2 π ∑ i = n - L + 1 n d i hq ( t - iT + τ ) ) ) ] t ( 7 )
[0022] The derivative of the phase pulse q(t) with respect to the symbol timing epoch is equal to the frequency pulse g(t) so that:
0 = ∫ T o Re [ j y ( t ) ∑ i = n - L + 1 n d i g ( t - iT + τ ) exp ( j ( ω o ( t + τ ) + θ + π ( ∑ i = - ∞ n - L d i h ) + 2 π ∑ i = n - L + 1 n d i hq ( t - iT + τ ) ) ) ] t ( 8 )
[0023] To derive a structure from the above equation, we can make a few assumptions. The data sequence vector d, and the carrier transmit phase, θ, are not known to the receiver. However, if the receiver is in a tracking mode so that carrier tracking errors are small, and the signal to noise ratio is high enough so that the detected data sequence is usually correct, then the receiver's estimates can be substituted for these parameters. The right hand side of equation (8) can then be used as an error signal to correct the current estimate of the symbol timing epoch reference. Furthermore, the term:
Re [ jexp ( j ( ω o ( t + τ ^ ) + θ + π ( ∑ i = - ∞ n - L d ^ i h ) + 2 π ∑ i = n - L + 1 n d ^ i hq ( t - iT + τ ^ ) ) ) ] ( 9 )
[0024] is just the receiver's estimate of the transmitted signal phase shifted by 90°.
[0025] [0025]FIG. 1 is a simplified block diagram of a Maximum Likelihood (ML) symbol timing estimator 10 which functions in accordance with equations (1)-(9). An input signal y(t) is provided to a CPM detector 11 and a multiplier 12 . The multiplier 12 multiplies the input signal y(t) with js(t), a regenerated transmit signal s(t) produced by a transmit signal regenerator 16 which is shifted by 90° through a phase shifter 19 and g(t), the transmit frequency signal. The output of the multipier 12 is passed through a low pass filter (LPF) 13 to provide an input control signal for a VCO 14 . The VCO 14 provides an output symbol timing reference signal τ to the CPM detector 11 , to the transmit signal regenerator 16 , and to the transmit signal frequency estimator 17 .
[0026] Based upon the tracking mode receiver as explained above, a phase estimator 18 provides a phase signal θ to the CPM detector 11 and also to the transmit signal regenerator 16 . The CPM detector 11 outputs a vector signal d to both the transmit signal regenerator 16 and the transmit frequency estimator 17 .
[0027] Much of the complexity in the Maximum Likelihood (ML) symbol timing tracking circuit of FIG. 1 is due to complexities of the transmit signal regenerator 16 and the multiplier 12 . A reduced complexity symbol timing estimation algorithm can be implemented which operates with a CPM signal that is demodulated using the Viterbi algorithm. The maximum likelihood symbol timing estimator performs a correlation similar to the correlation performed to compute the branch metric signals of the Viterbi algorithm. The branch metric signals in the trellis of the CPM signal are computed using
λ ( a ^ , m ) = ∫ t = mT mT + 1 y ( t ) Re [ exp ( j ( ω o ( t + τ ) + θ + π ( ∑ i = - ∞ m - L d i h ) + 2 π ∑ i = m - L + 1 m d i hq ( t - iT + τ ) ) ) ] t ( 10 )
[0028] A distinct branch metric signal is computed for each branch of the trellis. We now define
Θ m - L = π ( ∑ i = - ∞ m - L d i h ) ( 11 )
[0029] as a phase state of the branch, and
a m =( d m−L+1 , d m−L+2 , . . . d m ) (12)
[0030] as the correlative state of the branch. There are usually more than two distinct phase states, so that the computation of the branch metric signals for the same correlative state can be performed by using a complex correlator for the correlative state, and then by applying a phase rotation of this complex value to obtain the branch metric signal for each phase state. Two correlators compute the values.
λ I ( d , m ) = ∫ t = mT mT + 1 y ( t ) Re [ exp ( j ( ω o ( t + τ ) + θ + 2 π ∑ i = m - L + 1 m d i hq ( t - iT + τ ) ) ) ] t
and ( 13 ) λ Q ( d , m ) = ∫ t = nT nT + 1 y ( t ) Re [ exp ( j ( ω o ( t + τ ) + θ + 2 π ∑ i = m - L + 1 m d i hq ( t - iT + τ ) ) ) ] t ( 14 )
[0031] The computed values are multiplied by a complex number representing each of the possible values of equation 11. The real component after this multiplication is the desired branch metric signal of equation 10. The complex component is normally discarded. The complex component is defined as Q (a, m) and is
Q ( a , m ) = ∫ t = mT mT + 1 y ( t ) Re [ jexp ( j ( ω o ( t + τ ) + θ + π ( ∑ i = - ∞ m - L d i h ) + 2 π ∑ i = m - L + 1 m d i hq ( t - iT + τ ) ) ) ] ( 15 )
[0032] To facilitate the description of this reduced complexity timing epoch estimator, the error signal for estimation of the timing epoch is rewritten as
τ err = ∫ T o ∑ i = m - L + 1 m ^ i g ( t - iT + τ ^ ) Re [ j y ( t ) exp ( j ( ω o ( t + τ ^ ) + θ ^ + π ( ∑ i = - ∞ m - L ^ i h ) + 2 π ∑ i = m - L + 1 m d ^ i hq ( t - iT + τ ^ ) ) ) ] t ( 16 )
[0033] Equation 16 can be simplified by assuming that the first summation is constant over a T symbol period so that the error signal can be separated into two terms. Then the error signal is approximated as
τ err ≈ [ ∑ i = m - L + 1 m d ^ i g ( t - iT + τ ^ ) ] _ ∫ t = mT mT + 1 Re [ jy ( t ) exp ( j ( ω o ( t + τ ^ ) + θ ^ + π ( ∑ i = - ∞ m - L d ^ i h ) + 2 π ∑ i = m - L + 1 m d ^ i hq ( t - iT + τ ^ ) ) ) ] t ( 17 )
[0034] The integral term is the quantity Q (a, m) introduced above, and is computed in the branch metric signal calculations in the Viterbi algorithm.
[0035] [0035]FIG. 2 illustrates a reduced complexity symbol timing estimator 10 ′ in which in equation (17), the summation term,
∑ i = m - L + 1 m d i g ( t - iT + τ ) _ ( 18 )
[0036] is precalculated and stored in a lookup table 20. This summation term depends only on the last L output symbols of the Viterbi decoder. The values are precomputed and are stored in the lookup table 20 having a size M L .
[0037] A multiplier 21 then multiplies the output of the lookup table 20 with the output Q p,s of the CPM detector 11 . The output of the multiplier 21 is filtered by the low pass filter 13 and controls the phase of the VCO 14 output to produce the symbol timing reference signal τ.
[0038] [0038]FIG. 3 illustrates a CPM receiver 30 which uses a Viterbi algorithm to perform sequence detection on a received symbol sequence in a CPM signal. The CPM receiver computes the branch metric signals required in the Viterbi algorithm, which requires an accurate estimate of the phase of the transmitter's symbol clock signal with respect to the received signal, which is termed symbol timing epoch synchronization. The CPM receiver 30 uses a Viterbi trellis (termed trellis because it looks like an interweaved trellis) decoder or demodulator 36 to demodulate the CPM signals. The decoder 36 represents, by nodes, the possible states of the shift registers of the modulator, and by lines joining the nodes, the possible paths by which transitions between states can be made. The decoder 36 computes a distinct branch metric signal for each branch of the trellis, which is representative of the likelihood that that branch is in a modulator path. The decoder 36 uses the computed branch metric signals to select one path through the trellis having the highest probability of representing the CPM modulated data signal.
[0039] Referring to FIG. 3, a received input signal y(t) is applied to a first input port of a correlative branch calculator 32 . An estimated transmitter phase reference θ from phase estimator 18 and an estimated symbol timing signal τ from VCO 14 are applied to second and third input ports of the calculator 32 , which calculates and produces output signals λ i (A, m) and λ q (A, m) according to equation (10). The calculated signals λ i (A, m) and λ q (A, m) are applied to a phase rotator 34 which rotates the phase thereof to produce outputs which are applied to the Viterbi decoder 36 . The Viterbi decoder 36 performs the usual determination of the most likely trellis state, and produces an output {overscore (d)} of the estimated data sequence. The Viterbi decoder 36 also keeps track of the phase transitions occurring in the trellis which are associated with paths leading to each state. A set of these phase transitions are associated with each current state. The Viterbi decoder selects the most likely or most probable state, and also outputs an associated set of phase transitions.
[0040] The present invention departs from a conventional CPM receiver by phase shifting the computed branch metric signals by π/2, to thereby generate phase shifted branch metric signals associated with each path. At each symbol interval, a symbol timing estimator selects the associated phase shifted branch metric signal for that one path having the highest probability. The symbol timing estimator multiplies the selected phase shifted branch metric signal by a term representative of a summation of a plurality of weighted frequency pulses, and uses the resultant product to produce a symbol timing reference signal τ, which the CPM detector uses to adjust the timing epoch.
[0041] The embodiment of FIGS. 1 and 2 are related and merely use different signals which are generated and already computed in the CPM detector.
[0042] The embodiment of FIG. 1 takes the computed data vector signal {overscore (d)} of the CPM detector, and uses the symbol timing reference output signal τ and the estimated phase θ of the transmitter symbol clock signal to produce a highest probability brand metric signal s(t), which is then 90° phase shifted to produce js(t), one input to multiplier 12 . The transmitted signal frequency estimator uses the same two input signals of {overscore (d)} and τ to produce g(t). The multiplier 12 then multiplies the input signal y(t) by each of the two signals js(t) and g(t), and the product controls the frequency of VCO 14 which produces the symbol timing reference signal τ, which is an input to the CPM detector 11 .
[0043] The embodiment of FIG. 2 uses two signals which are computed by the CPM detector, the data vector signal {overscore (d)}, and Qps which is merely the selected highest probability branch metric signal js(t) multiplied by the CPM input signal y(t). the data signal {overscore (d)} is input to a lookup data table 2, which then provides g(t), the transmit frequency signal g(t), which is multiplied by multiplier 21 with Qps=js(t)x y(t), to produce an output signal which controls the VCO to produce the symbol timing estimator signal τ.
[0044] Both embodiments are related by performing a similar multiplication of the input signal y(t), the transmit frequency signal g(t), and the phase-shifted highest probability signal js(t).
[0045] The assumption that the summation of the frequency pulses is constant over a symbol interval will in general cause a degradation of the estimator with respect to the maximum likelihood estimator. Simulations have shown that the degradation is modest for many types of CPM modulations.
[0046] While several embodiments and variations of the present invention for a simplified symbol timing tracking circuit for a CPM modulated signal are described in detail herein, it should be apparent that the disclosure and teachings of the present invention will suggest many alternative designs to those skilled in the art. | A symbol epoch tracking circuit and method for a Continuous Phase Modulation (CPM) receiver. A phase tracking circuit performs carrier phase tacking with little extra computation for a Viterbi decoder and has an excellent tracking performance. The method can be used in CPM demodulators employing a Viterbi algorithm for data detection. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to dredging equipment and more specifically, to a portable dredging apparatus comprising a cutter housing in communication with a hydraulic power supply and a discharge pump through lengths of tubing whereby said cutter housing is submersible. The cutter housing is comprised of a platform having walls depending therefrom with the cutter blade positioned therewithin and height adjustable wheels exteriorly located on opposing sides. Also extending between the walls proximate to the cutter blade is an angularly positioned wiper element designed to dislodge debris caught between the teeth of the cutter blade. Angularly depending screen situated between the wiper blade and discharge port located in the rear wall prevent objects larger than the screen mesh from discharge port passage.
Releasably fastened to the exterior side of the discharge port is an appropriate length of flexible conduit terminating at a remote discharge pump with additional conduit extending from the discharge pump to a desired debris discharge location.
Located on the topside of the cutter housing is a handle providing means for navigating the cutter housing through a cutter task and having control means mounted thereon to raise and lower the wheels and engage and disengage a deck mounted hydraulic motor powering the cutter blade.
An additional element is provided in the form of a trailer providing means for transporting the hydraulic power plant, cutter housing, discharge pump and lengths of conduit.
2. Description of the Prior Art
There are other devices designed for dredging. Typical of these is U.S. Pat. No. 1,415,113 issued to Phillips, Jr. on May 9, 1922.
Another patent was issued to Jacobsen on Jul. 29, 1952 as U.S. Pat. No. 2,605,090. Yet another U.S. Pat. No. 3,808,779 was issued to Randall on May 7, 1974 and still yet another was issued on Oct. 5, 1982 to Sloan as U.S. Pat. No. 4,352,251.
Another patent was issued to Campbell on Feb. 15, 1983 as U.S. Pat. No. 4,373,867. Yet another U.S. Pat. No. 4,409,746 was issued to Beck on Oct. 18, 1983. Another was issued to Wilson, et al. on Apr. 18, 1989 as U.S. Pat. No. 4,822,106 and still yet another was issued on Dec. 26, 1989 to Cornelius as U.S. Pat. No. 4,889,391.
Another patent was issued to Wirth on Jul. 15, 1997 as U.S. Pat. No. 5,647,691. Yet another U.S. Pat. No. 6,843,003 was issued to Araoka on Jan. 18, 2005. Another was issued to Kubosawa on Nov. 14, 1981 as Japanese Patent No. JP56146524 and still yet another was issued on Jan. 23, 1996 to Inaba as Japanese Patent No. JP8020965. Another was issued to Fujimura on Mar. 5, 1996 as Japanese Patent No. JP8060695 and still yet another was issued on Mar. 4, 1997 to Goto as Japanese Patent No. JP9060035.
U.S. Pat. No. 1,415,113
Inventor: Thomas H. Phillips, Jr.
Issued: May 9, 1922
A clam or mussel dredging apparatus comprising a pipe adapted to extend obliquely downwardly into the water and having a mouth at an angle to said pipe to rest substantially flatly on the bottom, a second pipe adjacent the first pipe- and arranged to discharge air or other gas so as to rise through the first pipe causing eruption of the bottom under said mouth and a rising current of air, water, and bottom, and means for forcing air through said second pipe.
U.S. Pat. No. 2,605,090
Inventor: K. Oscar F. Jacobsen
Issued: Jul. 29, 1952
In underwater placer mining apparatus a nozzle unit comprising a generally axially extending suction conduit having a lower end portion disposed generally upright in the nozzle unit's operative position, a plurality of suction branch conduits of substantially smaller size branching outward from said lower end portion and turned downward and generally inward at an incline to the vertical, said branch conduits terminating in lower end portions forming suction inlets for drawing of loose bottom materials into said branch conduits, pressure conduit means including a plurality of downwardly extending pressure branch conduits terminating in lower end portions forming similarly directed force jets directed generally downwardly and appreciably inwardly and tangentially about the nozzle unit's axis to create, a vortex swirl of loose bottom materials in the vicinity of said suction inlets to be drawn into said suction inlets.
U.S. Pat. No. 3,808,779
Inventor: Alan C. Randall
Issued: May 7, 1974
Diver from boat working along ocean bottom cuts Irish Moss, agar weed, or similar marine vegetation growing at depth of up to about 100′, using a manually maneuvered sickle bar cutting unit which carries and is powered by a light weight air motor. Cutting unit further includes a collecting hood to which a flexible suction hose is attached for hydraulic delivery of the cut plants via an airlift, by which the suction is induced, to the surface and into a collecting strainer in or alongside the boat. Airlift is positioned just below the water surface and is spaced by the flexible suction hose a considerable distance away from the diver. Cutting unit air motor receives driving air, and diver receives breathing air from air compressor aboard the boat. Airlift receives driving air preferably from said air compressor, and cutting unit air motor preferably exhausts to atmospheric pressure, but said motor exhaust air could be utilized to drive airlift. Cutting unit oriented for side-to-side sweeping movement in cutting of plant stalks, and several hood configurations are described. Cutting blade has relatively short length, and air motor is relatively small. Airlift delivery tube receives driving air via a relatively large number of small diameter air apertures therethrough, the apertures being angled 2′0° upwardly, and the sum of their areas being 50 percent larger than the interior diameter of the delivery tube.
U.S. Pat. No. 4,352,251
Inventor: Albert H. Sloan
Issued: Oct. 5, 1982
A portable and lightweight suction dredge head which is held by a diver and is hand operated so as to be easily moved about in the working position. These heads are, for example of sizes from three inches to eight inches in intake diameter. The dredge head is used for excavating under water and is of the suction type wherein the material is conveyed away from a suction pipe from the dredge head. A jet digger may also be used with the dredge head. A manually operated valve on the dredge head permits the operator to regulate the amount of suction at the inlet of the dredge head and is capable of reducing the amount of suction so as to permit the operator to (1) adjust the density of the material being conveyed, that is regulate the amount of sludge or trash relative to the amount of water that is being conveyed, (2) control the digging aggressiveness of the dredge head, or (3) easily remove foreign material such as rocks, cans or other matter from the inlet of the dredge head or free his hand or foot if it accidently is grabbed by the dredge head. The head is rotatably mounted on the suction pipe which leads to a remote location whereby the head can be easily rotated at the most desirable digging position, and means are provided for insuring that the swivel coupling remains clear of sand or the like and freely operative. The above dredge head together with a hydraulically driven submersible pump assembly act to eliminate pump priming difficulties and pump sealing problems due to abrasive material, and provides good net positive head, horsepower, speed control, safety and mobility.
U.S. Pat. No. 4,373,867
Inventor: Gene K. Campbell
Issued: Feb. 15, 1983
A pumping system is described for pumping fluids, such as water with entrained mud and small rocks, out of underground cavities such as drilled wells, which can effectively remove fluids down to a level very close to the bottom of the cavity and which can operate solely by compressed air pumped down through the cavity. The system utilizes a subassembly having a pair of parallel conduit sections (44, 46) adapted to be connected onto the bottom of a drill string utilized for drilling the cavity, the drill string also having a pair of coaxially extending conduits. The subassembly includes an upper portion which has means for connection onto the drill string and terminates the first conduit of the drill string in a plenum (55). A compressed air-driven pump (62) is suspended from the upper portion. The pump sucks fluids from the bottom of the cavity and discharges them into the second conduit. Compressed air pumped down through the first conduit (46) to the plenum powers the compressed air-driven pump and aerates the fluid in the second conduit to lift it to the earth's surface.
U.S. Pat. No. 4,409,746
Inventor: Jeffrey L. Beck
Issued: Oct. 18, 1983
A dredging apparatus has a chamber with a substantially circular cross section. A first inlet and outlet is formed through the chamber with an axis of the inlet and outlet normal to a diameter of the chamber. A suction inlet is formed through the axis of the chamber along the axis of the vortex formed as the fluids leave the inlet and pass to a second outlet formed substantially coaxially with the vortex. Apparatus is provided for supporting the dredging apparatus in a position so that the suction inlet can remove material desired to be dredged.
U.S. Pat. No. 4,822,106
Inventor: Steven M. Wilson, et al.
Issued: Apr. 18, 1989
A golf ball dredge which comprises a shallow draft, buoyant support vessel in the form of a pontoon boat that provides a floating platform from which the dredging apparatus is supported. The pontoon boat has a small outboard motor mounted at its bow for providing a means for propulsion and steering of the boat. A relatively high pressure, gasoline powered, centrifugal water pump is mounted on the pontoon boat with its suction intake located below the water level. The pump provides a high pressure water outlet discharge that is supplied through eductor tubes into the inlet end of a bottom suction intake piping system. The bottom suction intake piping system also is supported on the pontoon boat with its inlet end submerged below the surface of the water to a suitable depth for lightly contacting the bottom of the waterhole. The high pressure water discharge from the pump is supplied through the eductor tubes to the inlet end of the suction intake piping system for creating a suction action that draws water and any entrained solids such as golf balls into the suction intake piping system. The suction intake piping system discharges under relatively high pressure water and any entrained solids into the inlet end of an automatically operable golf ball separator means supported on the pontoon boat for automatically separating out golf balls from liquid and other entrained solids contained in the suction intake piping system discharge without requiring the need for human intervention in the separating procedure.
U.S. Pat. No. 4,889,391
Inventor: Billie G. Cornelius
Issued: Dec. 26, 1989
A hand-held suction dredge and metal detector is supported on a vertically held hollow pipe. A metal detector having a central aperture is slidably supported on the pipe with the lower pipe end extending therethrough for receiving and transmitting at least partially fluid material. A spring urges the metal detector toward an initial position at the lower end of said pipe. A fluid jet is positioned in the pipe directed upward therein. A pump supported on the pipe and connected to the fluid jet circulate fluid to create a suction in the pipe to draw at least partially fluid material through the pipe to discharge the same from the upper end thereof. A perforate basket on the upper end of the pipe has openings sized to permit discharge of fluid material and retain larger metal solids therein. The pipe, in use, supports the metal detector adjacent to a region being investigated for dredging material by operation of the pump. A motor supported on the pipe operates the pump. The dredge and detector are constructed to locate metal objects in sand or loose soil, or underwater, and the pump is a high capacity air blower or water pump, and the jet is of a size and shape to induce suction through the pipe on circulation of air or water therethrough. Circularly extending trays in the basket are positioned to catch and retain solid metal objects drawn through said pipe while allowing fluid or particulate material to flow out through the openings in the basket.
U.S. Pat. No. 5,647,691
Inventor: John C. J. Wirth
Issued: Jul. 15, 1997
A method and apparatus for ecologically safely removing silt, muck, and sand from a waterbottom and for collecting the silt, muck, and sand without destroying the benthos therein into porous containers where the then contained mud and silt can be ecologically positioned where desired to enhance subaquatic environments. The apparatus includes a silt and mud collecting and transfer device that has no moving parts, thereby not endangering the benthos in the transfer process.
U.S. Pat. No. 6,843,003
Inventor: Toshinobu Araoka
Issued: Jan. 18, 2005
The gravel-or-the-like removing device includes an impeller casing which accommodates an impeller driven by a motor in the inside thereof and has a suction opening at the center of the lower surface, a peripheral wall for preventing collapse and inflow of gravel or the like which is constituted of a cylindrical body which has an upper end thereof connected to a lower portion of the impeller casing and a lower end thereof opened downwardly and forms a water-retention space in the inside thereof, and a water suction pipe which has an upper-end opening thereof opened in water above a gravel-or-the-like piled level and a lower opening thereof communicably connected with the water retention space.
Japan Patent Number JP56146524
Inventor: Minoru Kubosawa, et al.
Issued: Nov. 14, 1981
PURPOSE: To dredge sand and mud in a pit or the like at a high efficiency by providing a sand pump with a mud suction tube and a mud feed tube and a sink and float device to a body with a warped bottom section in a basket type sand/mud dredging apparatus.
CONSTITUTION: When an air suction/discharge valve 25 is opened, air is fed into a float 16 while water inside is discharged from a water suction/discharge port 16A. The float 16 comes up to float the body maintaining it at a specified position. When the air suction/discharge valve 25 is closed to halt the air supply, the air in the float 16 is discharged to reduce the pressure. As water enters the float 16, the body 11 submerges down, collects accumulated earth 9 and sucks it into a mud suction tube 13.
Japan Patent Number JP8020965
Inventor: Koji Inaba
Issued: Jan. 23, 1996
PURPOSE: To dredge hard mud with high efficiency by a method wherein agitating devices are disposed in front of and both sides of a vertical type screw conveyor and a mud collecting plate is arranged to the outside of the mud intake port of a conveyor.
CONSTITUTION: A hydraulic motor 217a is driven and agitating blades 218A and 218B of an agitating 216 are rotated to excavate mud. Excavated mud is guided to a mud suction port 214 by a mud collecting plate arranged at the back of the mud suction port 214 of a casing 211. The mud is inputted on a vertical screw conveyor 210 through a mud suction port 214 and transferred upward. Further, mud is pressurized by a pressure pump 220 and conveyed through a discharge pipe 250 by compressed air injected in the discharge pipe 250 through an ejector 260.
Japan Patent Number JP8060695
Inventor: Norihiko Fujimura, et al.
Issued: Mar. 5, 1996
PURPOSE: To dredge efficiently by mounting a plurality of edges to the bottom of a dredging cylinder, mounting a plurality of water jet nozzles to the outer periphery of the dredging cylinder, and housing turnably an impeller inside the dredging cylinder.
CONSTITUTION: Water is supplied to a water jet nozzle 9 by way of a pipe 7 mounted to a dredging cylinder 2 where the jet water is sprayed to accumulated mud, while edges 5 are pulled, thereby loosening the accumulated mud. An impeller 12 having a plurality of blades 11 installed to a rotary inner cylinder 10 is driven with a submergible motor 14, thereby agitating the loosen mud so as to turn the mud into fine particles. Furthermore, the fine particle mud is sucked up with a slurry pump installed to the top of a dredging mechanism 1.
Japan Patent Number JP9060035
Inventor: Seiichi Goto, et al.
Issued: Mar. 4, 1997
PROBLEM TO BE SOLVED: To efficiently and stably dredge suspended mud as well as soft mud.
SOLUTION: A casing 1, in the bottom face of which a opening 2 is provided, is divided into an excavation chamber 8 and a pump chamber 9 by a partition panel 7, and an excavation device 11, which excavates bottom mud 20 through the opening 2 and sends it to the pump chamber 9, and a mud pumping-up pump 12 are arranged in the excavation chamber 8 and pump chamber 9 respectively. Air pipes 28 and 29, which are used to selectively send compressed air to the excavation chamber 8 and pump chamber 9 from an air supply and exhaust device 31, are connected to the top face of the easing 1. In order to dredge soft mud, air pressure in the excavation chamber 8 is made to increase, and the pump chamber 9 is opened in the atmospheric air for performing high density dredging and the air leaked from the excavation chamber 8 to the pump chamber 9 is relieved in the atmosphere through the air pipe 29. In order to dredge suspended mud, the excavation chamber 8 is opened in the atmosphere, and air pressure in the pump chamber 9 is made to increase, and suspended mud is dredged by a suction method while preventing the production of a water passage between the opening 2 of the casing 1 and the mud pumping-up pump 12.
While these dredging devices may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention, as hereinafter described.
SUMMARY OF THE PRESENT INVENTION
A primary object of the present invention is to provide a portable dredging apparatus capable of cutting through calcified material such as coral.
Another object of the present invention is to provide a portable dredging apparatus comprising a hydraulic power plant, cutting member, discharge pump and appropriate lengths of conduit.
Yet another object of the present invention is to provide a portable dredging apparatus wherein said cutting member is submersible and connected by length of conduit to said hydraulic power plant and discharge pump.
Still yet another object of the present invention is to provide a portable dredging apparatus wherein said cutting member is comprised of a platform having walls depending therefrom having exteriorly mounted wheels for mobility.
Another object of the present invention is to provide a portable dredging apparatus wherein said cutter platform has a hydraulic motor mounted thereon driving the cutter blade.
Additional objects of the present invention will appear as the description proceeds.
The present invention overcomes the shortcomings of the prior art by providing a portable dredging apparatus comprising a cutter housing in communication with a hydraulic power supply and a discharge pump through lengths of tubing whereby said cutter housing is submersible. The cutter housing is comprised of a platform having walls depending therefrom with the cutter blade positioned therewithin and height adjustable wheels exteriorly located on opposing sides. Also extending between the walls proximate to the cutter blade is an angularly positioned wiper element designed to dislodge debris caught between the teeth of the cutter blade. Angularly depending screen situated between the wiper blade and discharge port located in the rear wall prevent objects larger than the screen mesh from discharge port passage. Releasably fastened to the exterior side of the discharge port is an appropriate length of flexible conduit terminating at a remote discharge pump with additional conduit extending from the discharge pump to a desired debris discharge location.
Located on the topside of the cutter housing is a handle providing means for navigating the cutter housing through a cutter task and having control means mounted thereon to raise and lower the wheels and engage and disengage a deck mounted hydraulic motor powering the cutter blade.
An additional element is provided in the form of a trailer providing means for transporting the hydraulic power plant, cutter housing, discharge pump and lengths of conduit.
The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawings, like reference characters designate the same or similar parts throughout the several views.
The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
In order that the invention may be more fully understood, it will now be described, by way of example, with reference to the accompanying drawing in which:
FIG. 1 is an illustrative view of the present invention in use;
FIG. 2 is an illustrative view of the present invention;
FIG. 3 is a perspective view of the dredger of the present invention;
FIG. 4 is a detailed perspective view of the dredger deck of the present invention;
FIG. 5 is a detailed view of the present invention;
FIG. 6 is a detailed view of the under deck of the present invention's dredge;
FIG. 7 is a perspective view of the hydraulic power plant of the present invention;
FIG. 8 is a detailed view of the hydraulic power plant of the present invention;
FIG. 9 is a detailed view of the hydraulic power plant of the present invention;
FIG. 10 is a detailed view of the hydraulic power plant of the present invention;
FIG. 11 is a top view of the hydraulic power plant of the present invention on trailer; and
FIG. 12 is a partial side view of the dredge unit of the present invention.
DESCRIPTION OF THE REFERENCED NUMERALS
Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, the figures illustrate the Portable Dredging Apparatus of the present invention. With regard to the reference numerals used, the following numbering is used throughout the various drawing figures.
10 Portable Dredging Apparatus of the present invention 12 dredge unit 14 hydraulic power plant 16 trash pump 18 housing of 12 20 platform of 18 22 sidewalls of 18 24 undercarriage of 18 26 cutting element 28 cutting blades 30 wiper blade 32 discharge port 34 screen 36 handle member 38 user controls 40 hydraulic hose lines of 12 42 hydraulic hose lines of 14 44 chain drive 46 user controls 48 cutter-depth adjustments means 50 dead man's clutch 52 emergency kill switch 54 gas tank of 14 56 battery 58 engine 60 hydraulic fluid tank 62 hydraulic fluid filter 64 hydraulic pump 66 pressure regulator 68 pressure gauge 70 throttle 71 hours meter 72 choke 73 engine muffler 74 ignition 76 suction line of 16 78 discharge line of 16 80 height-adjustable wheels 82 trailer 84 hose storage area
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The following discussion describes in detail one embodiment of the invention (and several variations of that embodiment). This discussion should not be construed, however, as limiting the invention to those particular embodiments, practitioners skilled in the art will recognize numerous other embodiments as well. For definition of the complete scope of the invention, the reader is directed to appended claims.
FIG. 1 is an illustrative view of the present invention 10 in use. Dredging equipment is normally enormous and expensive, the dredge unit 12 of the present invention 10 is small and can enter the water from a beach or be lowered into the water by a boatlift. An area around an owner's dock or swimming area could be cleaned up and/or deepened in a matter of hours with little impact, noise or expense. The dredge unit 12 is small, similar to a large lawn mower or snow blower. Cutter blades on the underside of the mower deck loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose. The cutter blades are powered by a hydraulic motor mounted on the deck. A separate hydraulic power plant 14 remains on shore or in a boat.
FIG. 2 is an illustrative view of the present invention 10 . The present invention is a dredge unit 10 comprising a submersible housing having a hydraulically driven cutter blade incorporating means for engaging and disengaging said cutter blade. The dredge apparatus 10 includes a remote hydraulic power plant 14 and a trash pump 16 . The hydraulic power plant 14 has hydraulic hose lines 42 that connect to the hydraulic hose lines 40 of the dredge unit 12 . The trash pump 16 includes a suction line 76 in communication with the dredge unit 12 and a discharge line 78 for disposing of the dredged material.
FIG. 3 is a perspective view the dredge unit 12 of the present invention. The dredge unit 12 is small, similar to a large lawn mower or snow blower. The housing 18 of the dredge unit 12 includes a deck platform 20 with sidewalls 22 extending downward therefrom. A handle member 36 extends from the housing 18 and has a plurality of user controls 46 mounted thereon including a cutter-depth adjustment control 48 , a dead man's clutch 50 and an emergency kill switch 52 . Height adjustable front wheels 80 are shown on the housing 18 .
FIG. 4 is a detailed perspective view the housing 18 of the dredge unit 12 . The dredge unit 12 is small, similar to a large lawn mower or snow blower. The housing 18 of the dredge unit 12 includes a deck platform 20 with sidewalls 22 extending downward therefrom. A handle member 36 extends from the housing 18 . Cutter blades within the undercarriage 24 of the housing 18 loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose. The cutter blades are powered by a hydraulically-operated chain drive 44 . A separate hydraulic power plant remains on shore or in a boat.
FIG. 5 is a detailed view of the user controls 46 of the present invention. A handle member 36 extends from the housing 18 and has a plurality of user controls 46 mounted thereon including a cutter-depth adjustment control 48 , a dead man's clutch 50 and an emergency kill switch 52 . The dead man's clutch engages 50 the cutting blade when depressed and disengages it immediately upon being released.
FIG. 6 is a detailed view of the undercarriage 24 of the dredge unit 12 . A cutting element 26 comprising a plurality of cutting blades 28 disposed within the undercarriage 24 of the housing 18 serves to loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose connected to the discharge port 32 . The cutting element 26 is powered by a hydraulically-operated chain drive 44 mounted on the deck. A separate hydraulic power plant remains on shore or in a boat. A wiper blade 30 serves to dislodge debris retained by the cutting blades 28 . The filter screen 34 restricts the passage of debris into the discharge port 32 that is larger than its mesh openings.
FIG. 7 is a perspective view of the hydraulic power plant 14 of the present invention. Shown are the primary components of the hydraulic power plant 14 including: a gasoline tank 54 , a battery 56 , an engine 58 , a hydraulic fluid tank 60 , a hydraulic fluid filter 62 , a hydraulic pump 64 , a pressure regulator 66 , a pressure gauge 68 and a throttle 70 .
FIG. 8 is a detailed view of the hydraulic power plant 14 of the present invention showing the throttle 70 , the pressure gauge 68 and the pressure regulator 66 . Dredging equipment is normally enormous and expensive, the dredge equipment of the present invention is small and can enter the water from a beach or be lowered into the water by a boatlift. An area around an owner's dock or swimming area could be cleaned up and/or deepened in a matter of hours with little impact, noise or expense. The dredge is small, similar to a large lawn mower or snow blower. Cutter blades on the underside of the mower deck loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose. The cutter blades are powered by a hydraulic motor mounted on the deck. A separate hydraulic power plant remains on shore or in a boat.
FIG. 9 is a detailed view of the hydraulic power plant 14 of the present invention showing the gasoline tank 54 , hours meter 71 , throttle 70 , choke 72 , ignition 74 and the hydraulic hose lines 42 . Dredging equipment is normally enormous and expensive, the dredge equipment of the present invention is small and can enter the water from a beach or be lowered into the water by a boatlift. An area around an owner's dock or swimming area could be cleaned up and/or deepened in a matter of hours with little impact, noise or expense. The dredge is small, similar to a large lawn mower or snow blower. Cutter blades on the underside of the mower deck loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose. The cutter blades are powered by a hydraulic motor mounted on the deck. A separate hydraulic power plant remains on shore or in a boat.
FIG. 10 is a detailed view of the hydraulic power plant 14 of the present invention showing the hydraulic pump 64 , the battery 56 and the engine muffler 73 . Dredging equipment is normally enormous and expensive, the dredge equipment of the present invention is small and can enter the water from a beach or be lowered into the water by a boatlift. An area around an owner's dock or swimming area could be cleaned up and/or deepened in a matter of hours with little impact, noise or expense. The dredge is small, similar to a large lawn mower or snow blower. Cutter blades on the underside of the mower deck loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose. The cutter blades are powered by a hydraulic motor mounted on the deck. A separate hydraulic power plant remains on shore or in a boat.
FIG. 11 is a top view of the present invention 10 on a trailer 82 . The dredge unit 12 , hydraulic power plant 14 and trash pump 16 of the present invention 10 are stored and carried within a trailer 82 to its work destination and is small and can enter the water from a beach or be lowered into the water by a boatlift. There is also a hose storage area 84 . An area around an owner's dock or swimming area could be cleaned up and/or deepened in a matter of hours with little impact, noise or expense. The dredge is small, similar to a large lawn mower or snow blower. Cutter blades on the underside of the mower deck loosen up mud and cut away soft stone (limestone) which is then removed through a suction hose. The cutter blades are powered by a hydraulic motor mounted on the deck. A separate hydraulic power plant remains on shore or in a boat.
FIG. 12 is a partial side view of the dredge unit 12 of the present invention. The dredge unit 12 of the present invention is small, similar to a large lawn mower or snow blower, cutter blades 28 on the underside loosen up mud and cut away soft stone (limestone) which is then removed through suction hose attached to the discharge port 32 . The cutter blades 28 have excessive debris removed therefrom by the wiper blade 30 and a screen 34 filters out larger particles prior to introduction through the discharge port 32 .
It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.
While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | A portable dredging apparatus comprising a cutter housing in communication with a hydraulic power supply and a discharge pump through lengths of tubing whereby said cutter housing is submersible. The cutter housing is comprised of a platform having walls depending therefrom with the cutter blade positioned therewithin and height adjustable wheels exteriorly located on opposing sides. Also extending between the walls proximate to the cutter blade is an angularly positioned wiper element designed to dislodge debris caught between the teeth of the cutter blade. Angularly depending screen situated between the wiper blade and discharge port located in the rear wall prevent objects larger than the screen mesh from discharge port passage. Releasably fastened to the exterior side of the discharge port is an appropriate length of flexible conduit terminating at a remote discharge pump with additional conduit extending from the discharge pump to a desired debris discharge location. | 4 |
[0001] This application is a divisional of U.S. patent application Ser. No. 13/056,583 filed on Jan. 28, 2011, which is a national stage of international application No. PCT/US2009/051929 filed on Jul. 28, 2009, and it claims the benefit of priority to U.S. Provisional Patent Application No. 61/084,549 filed on Jul. 29, 2008.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to novel organic synthetic methodology and its application for providing compounds that are useful as inhibitors of 11β-hydroxy steroid dehydrogenase type 1.
[0003] Hydroxysteroid dehydrogenases (HSDs) regulate the occupancy and activation of steroid hormone receptors via the interconvertsion between steroid hormones and its inactive form. For a recent review, see Nobel et al., Eur. J. Biochem. 2001, 268:4113-4125.
[0004] There exist numerous classes of HSDs. The 11-beta-hydroxysteroid dehydrogenases (11 βHSDs) is an oxidoreductase whose oxidative component metabolises biologically active glucocorticosteroid (such as cortisol and corticosterone), to the inactive C-11 oxidised metabolites, cortisone and 11-dehydrocorticosternone. Ragosh, et al., J. Endocrinology, 1997, 155:171-180.
[0005] The isoform 11-beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is expressed in liver, adipose tissue, brain, lung and other glucocorticoid tissue and is a potential target for therapy directed at numerous disorders that may be ameliorated by reduction of glucocorticoid action, such as diabetes, obesity and age-related cognitive dysfunction. Seckl, et al., Endocrinology, 2001, 142:1371-1376.
[0006] The 11β-HSD1 isoform is also present in pancreatic islet cells where it is implicated to play a role in controlling insulin release. Oppermann et al., J. Biological Chemistry, 2000, 275(45): 34841-34844. Glucocorticoid hormones such as cortisol (active form) and cortisone (inactive keto form) play a critical role in the regulation of carbohydrate metabolism. Increased levels of cortisol, promotes gluconeogenesis and inhibits insulin release. This results in high serum glucose levels characteristic of diabetic pathogenesis. Conversely, the known 11β-HSD1 inhibitor carbenoxolone reverses the inhibition of insulin release by cortisol in a dose dependent manner and further enhances insulin sensitivity. These observations indicate that 11β-HSD1 in pancreatic islet cells plays an important role in regulating glucocorticoid metabolism and release of insulin. Thus, 11β-HSD1 is an important enzyme target for the development of anti-diabetic therapeutic agents.
[0007] The C5-substituted 2-amino thiazolinones have been shown to be potent inhibitors of 11β-HSD1. In particular, 5S-2-(bicycle[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one, which is shown below, is a potent nanomolar inhibitor of this enzyme. Current synthetic routes to prepare this 2-aminothiazolone analog entail multiple steps and the use of high equivalents of an expensive chiral catalyst for the enantioselective addition of the isopropyl group to the C-5 atom of the parent 2-aminothiazolone.
[0000]
[0008] There appears, therefore, a need for alternative synthetic methodology that would allow the facile and stereoselective preparation of 5S-2-(bicycle[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one and related compounds employing commercially available starting materials and small quantities of a chiral catalyst.
SUMMARY OF THE INVENTION
[0009] The present invention satisfies this need and others by providing efficient synthetic routes for the preparing a compound of formula 2, its tautomer, stereoisomer or pharmaceutically acceptable salts thereof
[0000]
[0010] Thus, one embodiment of the invention is a method for making a compound of formula 2 by reacting a compound of formula 1:
[0000]
[0011] with a compound of formula R a R b NH.
[0012] In formulae 1 and 2, the variable X is selected from the group consisting of S, O, and NR, whilst Y is either R″C(O)NH, or SR″. In one embodiment, X is a nitrogen atom and R is selected from the group consisting of hydrogen, (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 4 -C 8 )bicycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl.
[0013] In various embodiments of the present invention, R″ in leaving group “Y” is selected from the group consisting of (C 1 -C 8 )alkyl, aryl, (C 3 -C 8 )cycloalkyl, and aryl(C 1 -C 6 )alkyl.
[0014] The C-5 substituents R 1 and R 2 are independently selected from the group consisting of hydrogen, (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl, with the proviso that R 1 and R 2 are not simultaneously hydrogen atoms.
[0015] In various embodiments of the present invention, substituents R a and R b of compound R a R b NH can either be the same or different groups. Thus, R a is selected from the group consisting of hydrogen, (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C3-C8)cycloalkyl, (C 4 -C 8 )bicycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl.
[0016] Substituent R b is selected from the group consisting of (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 4 -C 8 )bicycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl.
[0017] In another embodiment, the present invention provides a method for making the compound of formula 1 by reacting a compound of formula 3 with a compound of formula Y—CN. The variables X, R 1 and R 2 in formula 3 are as defined above:
[0000]
[0018] In another embodiment, the present invention provides a process for preparing a compound of formula 4 its tautomer, stereoisomer, or pharmaceutically acceptable salt thereof:
[0000]
[0019] The process comprises reacting a compound of formula 5:
[0000]
[0020] with a compound of formula 6:
[0000]
[0021] In formulae 4, 5 and 6, the variable A is selected from the group consisting of S, O, and NR 5 , whilst Z is selected from the group consisting of halogen, OR 6 and SR 6 .
[0022] In one embodiment, X is a nitrogen atom and R 5 is selected from the group consisting of hydrogen, (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 3 -C 8 )heterocycloalkyl, substituted or unsubstituted heteroaryl, substituted or unsubstituted aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl.
[0023] In embodiments where leaving group Z is OR 6 and SR 6 , R 6 is selected from the group consisting of (C 1 -C 8 )alkyl, pentafluorophenyl, nitrophenyl, di-nitrophenyl, CF 3 -phenyl, p-toluenesulfonyl, and methanesulfonyl.
[0024] Furthermore, substituents R 3 and R 4 at C-5 are each independently selected from the group consisting of hydrogen, (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl; with the proviso that R 3 and R 4 are not simultaneously hydrogen atoms.
[0025] In various embodiments of the present invention, substituents R m and R n of compound 6 can either be the same or different groups. Thus, R m is selected from the group consisting of hydrogen, hydrogen, (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 4 -C 8 )bicycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl.
[0026] Similarly R n is selected from the group consisting of (C 1 -C 8 )alkyl, (C 2 -C 8 )alkenyl, (C 2 -C 8 )alkynyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxy(C 1 -C 4 )alkyl, (C 1 -C 8 )fluoroalkyl, (C 1 -C 8 )hydroxyalkyl, (C 3 -C 8 )cycloalkyl, (C 4 -C 8 )bicycloalkyl, (C 3 -C 8 )heterocycloalkyl, heteroaryl, aryl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, (C 3 -C 8 )heterocycloalkyl(C 1 -C 6 )alkyl, heteroaryl(C 1 -C 6 )alkyl and aryl(C 1 -C 6 )alkyl.
DETAILED DESCRIPTION
Definitions
[0027] As used herein, the terms have the following meanings:
[0028] The term “alkyl” as used herein refers to a straight or branched chain, saturated hydrocarbon having the indicated number of carbon atoms. For example, (C 1 -C 6 )alkyl is meant to include, but is not limited to methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, isohexyl, and neohexyl. An alkyl group can be unsubstituted or optionally substituted with one or more substituents as described herein throughout.
[0029] The term “alkenyl” as used herein refers to a straight or branched chain unsaturated hydrocarbon having the indicated number of carbon atoms and at least one double bond. Examples of a (C 2 -C 8 )alkenyl group include, but are not limited to, ethylene, propylene, 1-butylene, 2-butylene, isobutylene, sec-butylene, 1-pentene, 2-pentene, isopentene, 1-hexene, 2-hexene, 3-hexene, isohexene, 1-heptene, 2-heptene, 3-heptene, isoheptene, 1-octene, 2-octene, 3-octene, 4-octene, and isooctene. An alkenyl group can be unsubstituted or optionally substituted with one or more substituents as described herein below.
[0030] The term “alkynyl” as used herein refers to a straight or branched chain unsaturated hydrocarbon having the indicated number of carbon atoms and at least one triple bond. Examples of a (C 2 -C 8 )alkynyl group include, but are not limited to, acetylene, propyne, 1-butyne, 2-butyne, 1-pentyne, 2-pentyne, 1-hexyne, 2-hexyne, 3-hexyne, 1-heptyne, 2-heptyne, 3-heptyne, 1-octyne, 2-octyne, 3-octyne and 4-octyne. An alkynyl group can be unsubstituted or optionally substituted with one or more substituents as described herein below.
[0031] The term “alkoxy” as used herein refers to an —O-alkyl group having the indicated number of carbon atoms. For example, a (C 1 -C 6 )alkoxy group includes —O-methyl, —O-ethyl, —O-propyl, —O-isopropyl, —O-butyl, —O-sec-butyl, —O-tert-butyl, —O-pentyl, —O-isopentyl, —O-neopentyl, —O-hexyl, —O-isohexyl, and —O-neohexyl.
[0032] The term “aminoalkyl,” as used herein, refers to an alkyl group (typically one to six carbon atoms) wherein from one or more of the C 1 -C 6 alkyl group's hydrogen atoms is replaced with an amine of formula —N(R c ) 2 , wherein each occurrence of R c is independently —H or (C 1 -C 6 )alkyl. Examples of aminoalkyl groups include, but are not limited to, —CH 2 NH 2 , —CH 2 CH 2 NH 2 —, —CH 2 CH 2 CH 2 NH 2 , —CH 2 CH 2 CH 2 CH 2 NH 2 , —CH 2 CH 2 CH 2 CH 2 CH 2 NH 2 , —CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 NH 2 , —CH 2 CH 2 CH 2 N(CH 3 ) 2 , t-butylaminomethyl, isopropylaminomethyl and the like.
[0033] The term “aryl” as used herein refers to a 6- to 14-membered monocyclic, bicyclic or tricyclic aromatic hydrocarbon ring system. Examples of an aryl group include phenyl and naphthyl. An aryl group can be unsubstituted or optionally substituted with one or more substituents as described herein below.
[0034] The term “cycloalkyl” as used herein refers to a 3- to 14-membered saturated or unsaturated non-aromatic monocyclic, bicyclic or tricyclic hydrocarbon ring system. Included in this class are cycloalkyl groups which are fused to a benzene ring. Representative cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclobutenyl, cyclopentyl, cyclopentenyl, cyclopentadienyl, cyclohexyl, cyclohexenyl, 1,3-cyclohexadienyl, cycloheptyl, cycloheptenyl, 1,3-cycloheptadienyl, 1,4-cycloheptadienyl, -1,3,5-cycloheptatrienyl, cyclooctyl, cyclooctenyl, 1,3-cyclooctadienyl, 1,4-cyclooctadienyl, -1,3,5-cyclooctatrienyl, decahydronaphthalene, octahydronaphthalene, hexahydronaphthalene, octahydroindene, hexahydroindene, tetrahydroinden, decahydrobenzocycloheptene, octahydrobenzocycloheptene, hexahydrobenzocycloheptene, tetrahydrobenzocyclopheptene, dodecahydroheptalene, decahydroheptalene, octahydroheptalene, hexahydroheptalene, and tetrahydroheptalene, (1s,3s)-bicyclo[1.1.0]butane, bicycle[1.1.1]pentane, bicycle[2.1.1]hexane, Bicycle[2.2.1]heptane, bicycle[2.2.2]octane, bicycle[3.1.1]heptane, bicycle[3.2.1]octane, bicycle[3.3.1]nonane, bicycle[3.3.2]decane, bicycle[3.3.]undecane, bicycle[4.2.2]decane, bicycle[4.3.1]decane. A cycloalkyl group can be unsubstituted or optionally substituted with one or more substituents as described herein below.
[0035] The term “halo” as used herein refers to —F, —Cl, —Br or —I.
[0036] The term “haloalkyl,” as used herein, refers to a C 1 -C 6 alkyl group wherein from one or more of the C 1 -C 6 alkyl group's hydrogen atom is replaced with a halogen atom, which can be the same or different. Examples of haloalkyl groups include, but are not limited to, trifluoromethyl, 2,2,2-trifluoroethyl, 4-chlorobutyl, 3-bromopropyl, pentachloroethyl, and 1,1,1-trifluoro-2-bromo-2-chloroethyl.
[0037] The term “heteroalkyl,” by itself or in combination with another term, means, unless otherwise stated, a stable straight or branched chain alkyl, or combinations thereof, consisting of carbon atoms and from one to three heteroatoms selected from the group consisting of O, N and S, and wherein the nitrogen and sulfur atoms may optionally be oxidized and the nitrogen heteroatom may optionally be quaternized. The heteroatom(s) O, N and S can be placed at any position of the heteroalkyl group. Examples include —CH 2 —CH 2 —O—CH 3 , —CH 2 —CH 2 —NH—CH 3 , —CH 2 —CH 2 —N(CH 3 )—CH 3 , —CH 2 —S—CH 2 —CH 3 , —CH 2 —CH 2 —S(O)—CH 3 , —CH 2 —CH 2 —S(O) 2 —CH 3 , and —CH 2 —CH═N—OCH 3 . Up to two heteroatoms can be consecutive, such as, for example, —CH 2 —NH—OCH 3 . When a prefix such as (C 2 -C 8 ) is used to refer to a heteroalkyl group, the number of carbons (2 to 8, in this example) is meant to include the heteroatoms as well. For example, a C 2 -heteroalkyl group is meant to include, for example, —CH 2 OH (one carbon atom and one heteroatom replacing a carbon atom) and —CH 2 SH.
[0038] To further illustrate the definition of a heteroalkyl group, where the heteroatom is oxygen, a heteroalkyl group can be an oxyalkyl group. For instance, (C 2 -C 5 )oxyalkyl is meant to include, for example —CH 2 —O—CH 3 (a C 3 -oxyalkyl group with two carbon atoms and one oxygen replacing a carbon atom), —CH 2 CH 2 CH 2 CH 2 OH, and the like.
[0039] The term “heteroaryl” as used herein refers to an aromatic heterocycle ring of 5 to 14 members and having at least one heteroatom selected from nitrogen, oxygen and sulfur, and containing at least 1 carbon atom, including monocyclic, bicyclic, and tricyclic ring systems. Representative heteroaryls are triazolyl, tetrazolyl, oxadiazolyl, pyridyl, furyl, benzofuranyl, thiophenyl, benzothiophenyl, quinolinyl, pyrrolyl, indolyl, oxazolyl, benzoxazolyl, imidazolyl, benzimidazolyl, thiazolyl, benzothiazolyl, isoxazolyl, pyrazolyl, isothiazolyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, cinnolinyl, phthalazinyl, quinazolinyl, pyrimidyl, azepinyl, oxepinyl, quinoxalinyl and oxazolyl. A heteroaryl group can be unsubstituted or optionally substituted with one or more substituents as described herein below.
[0040] As used herein, the term “heteroatom” is meant to include oxygen (O), nitrogen (N), and sulfur (S).
[0041] As used herein, the term “heterocycle” refers to 3- to 14-membered ring systems which are either saturated, unsaturated, or aromatic, and which contains from 1 to 4 heteroatoms independently selected from nitrogen, oxygen and sulfur, and wherein the nitrogen and sulfur heteroatoms can be optionally oxidized, and the nitrogen heteroatom can be optionally quaternized, including, including monocyclic, bicyclic, and tricyclic ring systems. The bicyclic and tricyclic ring systems may encompass a heterocycle or heteroaryl fused to a benzene ring. The heterocycle can be attached via any heteroatom or carbon atom. Heterocycles include heteroaryls as defined above. Representative examples of heterocycles include, but are not limited to, aziridinyl, oxiranyl, thiiranyl, triazolyl, tetrazolyl, azirinyl, diaziridinyl, diazirinyl, oxaziridinyl, azetidinyl, azetidinonyl, oxetanyl, thietanyl, piperidinyl, piperazinyl, morpholinyl, pyrrolyl, oxazinyl, thiazinyl, diazinyl, dioxanyl, triazinyl, tetrazinyl, imidazolyl, tetrazolyl, pyrrolidinyl, isoxazolyl, furanyl, furazanyl, pyridinyl, oxazolyl, benzoxazolyl, benzisoxazolyl, thiazolyl, benzthiazolyl, thiophenyl, pyrazolyl, triazolyl, pyrimidinyl, benzimidazolyl, isoindolyl, indazolyl, benzodiazolyl, benzotriazolyl, benzoxazolyl, benzisoxazolyl, purinyl, indolyl, isoquinolinyl, quinolinyl and quinazolinyl. A heterocycle group can be unsubstituted or optionally substituted with one or more substituents as described herein below.
[0042] The term “heterocycloalkyl,” by itself or in combination with other terms, represents, unless otherwise stated, cyclic versions of “heteroalkyl.” Additionally, a heteroatom can occupy the position at which the heterocycle is attached to the remainder of the molecule. Examples of heterocycloalkyl include 1-(1,2,5,6-tetrahydropyridyl), 1-piperidinyl, 2-piperidinyl, 3-piperidinyl, 4-morpholinyl, 3-morpholinyl, tetrahydrofuran-2-yl, tetrahydrofuran-3-yl, tetrahydrothien-2-yl, tetrahydrothien-3-yl, 1-piperazinyl, 2-piperazinyl, and the like.
[0043] The term “hydroxyalkyl,” as used herein, refers to an alkyl group having the indicated number of carbon atoms wherein one or more of the hydrogen atoms in the alkyl group is replaced with an —OH group. Examples of hydroxyalkyl groups include, but are not limited to, —CH 2 OH, —CH 2 CH 2 OH, —CH 2 CH 2 CH 2 OH, —CH 2 CH 2 CH 2 CH 2 OH, —CH 2 CH 2 CH 2 CH 2 CH 2 OH, —CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 OH, and branched versions thereof.
[0044] Substituents for the groups referred to as alkyl, heteroalkyl, alkylene, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl and heterocycloalkenyl can be selected from a variety of groups including: —OR d ′, ═O, ═NR d ′, ═N—OR d ′, —NR d ′R d ″, —SR d ′, -halo, —SiR d ′R d ″R d ′″, —OC(O)R d ′, —C(O)R d ′, —CO 2 R d ′, —CONR d ′R d ″, —OC(O)NR d ′R d″ , —NR d ′″C(O)R d ′, —NR d ′″C(O)NR d ′R d ″, —NR d ′″SO 2 NR d ′R d ″, —NR d ″CO 2 R d ′, —NHC(NH 2 )═NH, —NR a ′C(NH 2 )═NH, —NHC(NH 2 )═NR d ′, —S(O)R d ′, —SO 2 R d ′, —SO 2 NR d ′R d ″, —NR d ″SO 2 R d ′, —CN and —NO 2 , in a number ranging from zero to three, with those groups having zero, one or two substituents being exemplary. R d ′, R d ″ and R d ′″ each independently refer to hydrogen, unsubstituted (C 1 -C 8 )alkyl, unsubstituted hetero(C 1 -C 8 )alkyl, unsubstituted aryl and aryl substituted with one to three substituents selected from -halo, unsubstituted alkyl, unsubstituted alkoxy, unsubstituted thioalkoxy and unsubstituted aryl(C 1 -C 4 )alkyl. When R d ′ and R d ″ are attached to the same nitrogen atom, they can be combined with the nitrogen atom to form a 5-, 6- or 7-membered ring. For example, —NR d ′R d ″ can represent 1-pyrrolidinyl or 4-morpholinyl. Typically, an alkyl or heteroalkyl group will have from zero to three substituents, with those groups having two or fewer substituents being exemplary of the present invention. An alkyl or heteroalkyl radical can be unsubstituted or monosubstituted. In some embodiments, an alkyl or heteroalkyl radical will be unsubstituted. From the above discussion of substituents, one of skill in the art will understand that the term “alkyl” is meant to include groups such as trihaloalkyl (e.g., —CF 3 and —CH 2 CF 3 ).
[0045] Exemplary substituents for the alkyl and heteroalkyl radicals include but are not limited to —OR d ′, ═O, ═NR d ′, ═N—OR d ′, —NR d ′R d ″, —SR d ′, -halo, —SiR d ′R d ″R d ′″, —OC(O)R d ′, —C(O)R d ′, —CO 2 R d ′, —CONR d ′R d ″, —OC(O)NR d ′R d ″, —NR d ″C(O)R d ′, NR d ′″C(O)NR d ′R d ″, —NR d ′″SO 2 NR d ′R d ″, —NR d ″CO 2 R d ′, —NHC(NH 2 )═NH, —NR a ′C(NH 2 )═NH, —NHC(NH 2 )═NR d ′, —S(O)R d ′, —SO 2 R d ′, —SO 2 NR d ′R d ″, —NR d ″SO 2 R d ′, —CN and —NO 2 , where R d ′, R d ″ and R d , are as defined above. Typical substituents can be selected from: —OR d ′, ═O, —NR d ′R d ″, -halo, —OC(O)R d ′, —CO 2 R d ′, —C(O)NR d ′R d ″, —OC(O)NR d ′R d ″, —NR d ″C(O)R d ′, —NR d ″CO 2 R d ′, —NR d ′″SO 2 NR d ′R d ″, —SO 2 R d ′, —SO 2 NR d ′R d ″, —NR d ″SO 2 R d ′—CN and —NO 2 .
[0046] Similarly, substituents for the aryl and heteroaryl groups are varied and selected from: -halo, —OR e ′, —OC(O)R e ′, —NR e ′R e ″, —SR e ′, —R e ′, —CN, —NO 2 , —CO 2 R e ′, —C(O)NR e ′R e ″, —C(O)R e ′, —OC(O)NR e ′R e ″, —NR e ″C(O)R e ′, —NR e ″CO 2 R e ′, —NR e ′″C(O)NR e ′R e ″, —NR e ′″SO 2 NR e ′R e ″, —NHC(NH 2 )═NH, —NR e ′C(NH 2 )═NH, —NH—C(NH 2 )═NR e ′, —S(O)R e ′, —SO 2 R e ′, —SO 2 NR e ′R e ″, —NR e ″SO 2 R e ′, —N 3 , —CH(Ph) 2 , perfluoroalkoxy and perfluoro(C 1 -C 4 )alkyl, in a number ranging from zero to the total number of open valences on the aromatic ring system; and where R e ′, R e ″ and R e ′″ are independently selected from hydrogen, unsubstituted (C 1 -C 8 )alkyl, unsubstituted hetero(C 1 -C 8 )alkyl, unsubstituted aryl, unsubstituted heteroaryl, unsubstituted aryl(C 1 -C 4 )alkyl and unsubstituted aryloxy(C 1 -C 4 )alkyl. Typically, an aryl or heteroaryl group will have from zero to three substituents, with those groups having two or fewer substituents being exemplary in the present invention. In one embodiment of the invention, an aryl or heteroaryl group will be unsubstituted or monosubstituted. In another embodiment, an aryl or heteroaryl group will be unsubstituted.
[0047] Two of the substituents on adjacent atoms of an aryl or heteroaryl ring in an aryl or heteroaryl group as described herein throughout may optionally be replaced with a substituent of the formula -T-C(O)—(CH 2 ) q —U—, wherein T and U are independently —NH—, —O—, —CH 2 — or a single bond, and q is an integer of from 0 to 2. Alternatively, two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula -J-(CH 2 ) r —K—, wherein J and K are independently —CH 2 —, —O—, —NH—, —S—, —S(O)—, —S(O) 2 —, —S(O) 2 NR f ′— or a single bond, and r is an integer of from 1 to 3. One of the single bonds of the new ring so formed may optionally be replaced with a double bond. Alternatively, two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula —(CH 2 ) s —X—(CH 2 ) t —, where s and t are independently integers of from 0 to 3, and X is —O—, —NR f ′—, —S—, —S(O)—, —S(O) 2 —, or —S(O) 2 NR a ′—. The substituent R f ′ in —NR f ′— and —S(O) 2 NR f ′— is selected from hydrogen or unsubstituted (C 1 -C 6 )alkyl.
[0048] It is to be understood that if a —CO 2 H substituent is present, the —COOH group can optionally be replaced with bioisosteres such as:
[0000]
[0049] and the like. See, e.g., The Practice of Medicinal Chemistry ; Wermuth, C. G., Ed.; Academic Press: New York, 1996; p. 203.
[0050] It is also understood that coupling of two reagents frequently requires a functional group on one of the reagent to be activated prior to coupling. In this regard, the term “activation” denotes the standard use of conventional activating reagents. For example, a carboxyl group is activated via carboxyl activating agents. Reagents comprising a carboxyl group substituent may be activated by a variety of standard activating agents, such as thionyl chloride, phosphory chloride, diimidazolcarbonyl, N,N′-dicyclohexylcarbodiimide (DCC), N,N′-diisopropylcarbodiimide (DIC) or O-benzotriazol-1-yl-N,N,N′,N′-tetramethyluronium-hexafluorophosphate (HBTU), with or without 4-dimethylaminopyridine (DMAP), 1-hydroxybenzotriazole (HOBT), benzotriazol-1-yloxy-tris(dimethylamino)phosphonium-hexafluorophosphate (BOP), bis(2-oxo-3-oxazolidinyl) phosphine chloride (BOPCl), DEPBT (3-(Diethoxy-phosphoryloxy)-3 H-benzo[d][123]triazin-4-one), BEP (2-bromo-1-ethyl pyridinium tetrafluoroborate), HATU (N,N,N′,N′-tetramethyl-O-(7-azabenzotriazol-1-yl)uronium hexafluorophosphate), TBTU (N,N,N′,N′-tetramethyl-O-(benzotriazol-1-yl)uronium tetrafluoroborate), PyBop (benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate), and the like.
[0051] The compound of formula 2 can also exist in various isomeric forms, including configurational, geometric and conformational isomers, as well as existing in various tautomeric forms, particularly those that differ in the point of attachment of a hydrogen atom. As used herein, the term “isomer” is intended to encompass all isomeric forms of a compound of formula 2, including tautomeric forms of the compound.
[0052] Compounds of formula 2 have asymmetric centers and therefore exist in different enantiomeric and diastereomeric forms. A compound can exist in the form of an optical isomer or a diastereomer. Accordingly, the invention encompasses compounds of formula 2 in the forms of their optical isomers, diastereomers and mixtures thereof, including racemic mixtures.
[0053] As used herein and unless otherwise indicated, the term “stereoisomer” means one stereoisomer of a compound that is substantially free of other stereoisomers of that compound. For example, a stereomerically pure compound having one chiral center will be substantially free of the opposite enantiomer of the compound. A stereomerically pure compound having two chiral centers will be substantially free of other diastereomers of the compound. In some embodiments, a stereomerically pure compound comprises greater than about 80% by weight of one stereoisomer of the compound and less than about 20% by weight of other stereoisomers of the compound, for example greater than about 90% by weight of one stereoisomer of the compound and less than about 10% by weight of the other stereoisomers of the compound, or greater than about 95% by weight of one stereoisomer of the compound and less than about 5% by weight of the other stereoisomers of the compound, or greater than about 97% by weight of one stereoisomer of the compound and less than about 3% by weight of the other stereoisomers of the compound.
[0054] It should be noted that if there is a discrepancy between a depicted structure and a name given to that structure, the depicted structure controls. In addition, if the stereochemistry of a structure or a portion of a structure is not indicated with, for example, bold, wedged, or dashed lines, the structure or portion of the structure is to be interpreted as encompassing all stereoisomers of it.
Process of Preparation
[0055] The present invention provides two processes for the facile synthesis of 5-substituted 2-aminothiazolones as shown below in Schemes 1 and 2.
[0056] As would be readily recognized by a skilled artisan, the processes described herein allow the synthesis of various heterocycles represented by formula 2. Thus, in one embodiment, X is a sulfur or oxygen atom. In yet another embodiment, X is a substituted or unsubstituted amine, such as an alkyl amine or a substituted or unsubstituted aryl amine.
[0057] The identity of substituent groups R 1 and R 2 at position C-5 of the 2-amino thiazolone analog depends on the choice of the starting ketone (1). In one embodiment, R 1 and R 2 are both independently (C 1 -C 3 )alkyl groups. Examples of such groups include methyl, ethyl, propyl, and isopropyl groups. In one embodiment, the C-5 carbon atom bears a methyl and an isopropyl group. Alternatively, the present invention also contemplates the preparation of a compound of formula 2 where R 1 and R 2 are the same group or a compound where R 1 is alkyl and R 2 is an optionally substituted aryl, heteroaryl, alkynyl, alkenyl, cycloalkyl, or a heterocycloalkyl group.
[0058] The compound of formula 2 is obtained by displacing Y from the compound of formula 1 using an unsubstituted or substituted amine (NR a R b ). In one embodiment, therefore, R a is a hydrogen while R b is a cycloalkyl or a bicycloalkyl as described hereinabove. Thus, in some embodiments, R b is an unsubstituted bicycloalkane such as, for example, a norbornyl group (bicyclo[2.2.1]heptane).
[0059] In a further embodiment, leaving group Y in formula 1 is an alkyl or aryl amide. Alternatively, the leaving group is an alkyl or aryl thiol.
[0060] In still another embodiment, the inventive process provides a compound of formula 4 obtained via an intramolecular displacement reaction. Thus, A in formula 4 is either a sulfur atom, an oxygen atom or a substituted or unsubstituted amine obtained by reacting an appropriate guanidine moiety with the acyl halide of formula 5.
[0061] As mentioned above, the identity of substituent groups R 3 and R 4 at position C-5 of the 2-amino thiazolone analog depends on the choice of the starting ketone. In one embodiment, for instance, R 3 is methyl and R 4 is an isopropyl group.
[0062] In another embodiment, the leaving group Z in formula 5 is a halogen, an oxygen ester, a mesolate, a tosylate or a thioester. Other suitable leaving groups are well known in the art and are contemplated herein. When Z is a halogen, Z can be chlorine, bromine or an iodine.
[0063] The 5-substituted-2-aminothiazolones prepared using the inventive methodologies involve the asymmetric hydrocyanation reaction of an appropriate ketone to give a cyanohydrin. According to one aspect of the invention a metal catalyst and an appropriate chiral ligand is used for preparing the chiral cyanohydrin. While several catalyst-ligand pairs are well known in the art, in one embodiment the transition metal is aluminum having a formal oxidation state of +3.
[0064] Ligands suitable for use with the metal catalyst include monodentate and multidentate ligands. In one embodiment, when the ligand is monodentate, more than one monodentate ligand is typically utilized for coordinating to the metal.
[0065] In accordance with the normal definition in the art, “multidentate” refers to a ligand that coordinates to the transition metal or its ion through two or more atoms. Thus, for example, the ligand can be bidentate or tridentate. In another embodiment, the ligand is bidentate. An exemplary bidentate ligand is a phosphine that coordinates to the metal or ion through two phosphorus atoms. Other examples of bidentate ligands comprise, for example, various pairings of phosphorus, sulfur, nitrogen, and oxygen donor atoms. In still another embodiment the bidentate ligand is an analog of bromophenol blue.
[0066] The amount of catalyst can range in one embodiment from about 0.001 mol % to about 10 mol %. In another embodiment, the amount can range from about 0.01 mol % to about 5 mol %. In still another embodiment, the amount can range from about 0.1 mol % to about 1.0 mol %. An exemplary amount of catalyst is about 0.5 mol %.
[0067] Compounds of formulae 2 and 4, in addition to exhibiting chirality at C5, may contain one or more other stereochemical centers, and thereby provide for the presence of diastereomers. The invention contemplates the preparation of all such stereochemical isomers of a compound of formulae 2 and 4.
[0068] If needed, further purification and separation of enantiomers and diastereomers can be achieved by routine procedures known in the art. Thus, for example, the separation of enantiomers of a compound of formula 2 and 4 can be achieved by the use of chiral HPLC and related chromatographic techniques. Diastereomers can be similarly separated. In some instances, however, diastereomers can simply be separated physically, such as, for example, by controlled precipitation or crystallization.
[0069] The process of the invention, when carried out as prescribed herein, can be conveniently performed at temperatures that are routinely accessible in the art. In one embodiment, the process is performed at a temperature in the range of about 25° C. to about 110° C. In another embodiment, the temperature is in the range of about 40° C. to about 100° C. In yet another embodiment, the temperature is in the range of about 50° C. to about 95° C.
[0070] As generally described above, the process is performed in the presence of a base. The base can be any convenient organic or inorganic compound. Typically, the base is not nucleophilic. Thus, in one embodiment, the base is selected from carbonates, phosphates, alkoxides, and salts of disilazanes.
[0071] The process of the invention, when performed as described herein, can be substantially complete after several minutes to after several hours depending upon the nature and quantity of reactants and reaction temperature, for example. The determination of when the reaction is substantially complete can be conveniently evaluated by ordinary techniques known in the art such as, for example, HPLC, LCMS, TLC, and 1 H NMR.
EXAMPLES
[0072] The present invention is not to be limited in scope by the specific embodiments disclosed in the examples, which are intended to be illustrations of a few embodiments of the invention, nor is the invention to be limited by any embodiments that are functionally equivalent within the scope of this invention. Indeed, various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art and are intended to fall within the scope of the appended claims. To this end, it should be noted that one or more hydrogen atoms or methyl groups can be omitted from the drawn structures consistent with accepted shorthand notation of such organic compounds, and that one skilled in the art of organic chemistry would readily appreciate their presence.
[0000] Intermolecular Displacement Approach to the Synthesis of 5-disubstituted-2-aminothiazolones
[0073] In one embodiment of the present invention, synthesis of the target compound generally involves the asymmetric hydrocyanation of 3-methyl butane-2-one (1), to give the corresponding R-2-hydroxy-3-methyl butanenitrile. Activation of the hydroxyl by forming a mesolate prior to nucleophilic displacement with sodium sulfide results in the formation of the corresponding 2-mercapto-2,3-dimethylbutane nitrile having opposite (S—) stereochemistry at C-2. Hydrolysis of the cyano group followed by reaction of the resultant carboxylic acid (5) with methylisothiocyanate and cyclization of the resultant adduct gives (S)-5-methyl-2-(methylthio)thiazole-4(5H)-one (6). The target compound is obtained by reacting (6) with S-aminonorbornane. This reaction sequence is illustrated in Scheme 1 below, and the following examples refer to the numbering scheme employed in the reaction sequence.
[0000]
Example 1
Preparation of (R)-2,3-Dimethyl-2-(trimethylsilyloxy)butanenitrile (4)
[0074] TMSCN (28.8 g, 0.29 mol) and N,N-dimethylaniline oxide (0.2 g, 0.0015 mol) were dissolved in THF (75 mL) and the resultant solution was stirred for 1 h at 23° C. under an atmosphere of nitrogen. 3-Methylbutan-2-one (50.0 g, 0.58 mol) was added via syringe and the mixture was cooled to −30° C. 2-((E)-((1S,2S)-2-((E)-5-bromo-2-hydroxybenzylideneamino)-1,2-diphenylethylimino)methyl)-4-bromophenol (1.67 g, 0.0029 mol) and triethylaluminum (0.33 g, 0.0029 mol) were added and the reaction mixture was stirred for 24 h. The mixture was warmed to 23° C. and concentrated (30 mmHg). The residue was distilled under reduced pressure (30 mmHg, 80° C.) to yield 47.2 g (88%) of the title compound. 1 H NMR (400 MHz, CDCl 3 ) δ 1.86 (septaplet, 1H, J=4 Hz), 1.53 (s, 3H), 1.04 (d, 3H, J=4 Hz), 1.02 (d, 3H, J=4 Hz), 0.25 (s, 9H); 13 C NMR (100 MHz, CDCl 3 ) δ 121.5, 73.4, 39.1, 26.0, 17.1, 16.9, 1.15; IR (neat): 2969, 1375, 1254, 1160, 991, 841, 755 cm −1 ; Exact Mass (C 9 H 19 NOSi+Na): calculated=208.1128, measured=208.1130. [α] D at 23° C. and 21.0 g/L in CDCl 3 =+12.19. Chiral GC: 85.8% ee.
Example 2
Preparation of (R)-2-Cyano-3-methylbutan-2-ylmethanesulfonate
[0075] (R)-2,3-Dimethyl-2-(trimethylsilyloxy)butanenitrile (11.0 g, 0.059 mol) was dissolved in 2-MeTHF (110 mL) under an atmosphere of nitrogen. Water (2.2 mL) and CSA (0.68 g, 0.00295 mol) were added and the solution was stirred for 3 h. The reaction mixture was treated with saturated aqueous NaHCO 3 (100 mL), the phases were separated and the aqueous phase was extracted with 2-MeTHF (2×50 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure (˜1 mmHg).
[0076] The residue was dissolved in 2-MeTHF (100 mL) under an atmosphere of nitrogen. Et 3 N (10.9 mL, 0.077 mol) and MsCl (5.98 mL, 0.077 mol) were added via syringes and the reaction mixture was stirred for 2 h. The mixture was treated with saturated aqueous NaHCO 3 (100 mL), the phases were separated and the aqueous phase was extracted with 2-MeTHF (3×50 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure. Chromatographic purification (70 g silica gel, 10-20% EtOAc/Hexanes) of the residual material yielded 10.36 g (92%) of the title compound. 1 H NMR (400 MHz, CDCl 3 ) δ 3.17 (s, 3H), 2.24 (septuplet, 1H, J=8 Hz), 1.89 (s, 3H), 1.14 (t, 6H, J=8 Hz); 13 C NMR (100 MHz, CDCl 3 ) δ 116.7, 82.6, 39.7, 37.8, 23.1, 16.7, 16.6; IR (neat): 2979, 1466, 1358, 1180, 1048, 901, 805 cm −1 ; Exact Mass (C 7 H 13 NO 3 S+Na): calculated=214.0508, measured=214.0510. [α] D at 23° C. and 12.5 g/L in CDCl 3 =+14.98. Chiral GC: 85.44% ee.
Example 3
Preparation of (S)-2-mercapto-2,3-dimethylbutanoic acid (5)
[0077] NaSH hydrate (1.2 g, 0.097 mol) was dissolved in water (62 mL) and the solution was warmed to 45° C. under an atmosphere of nitrogen. The pH of the aqueous solution was adjusted to 8-9 by addition of 0.31 mL of concentrated aqueous HCl. (R)-2-Cyano-3-methylbutan-2-ylmethanesulfonate (3.1 g, 0.016 mol) was added via syringe and the reaction mixture was stirred for 20 h. To the resultant solution was added KOH (62 g, 1.1 mol) as a solid and the mixture was warmed to 95° C. The solution was stirred for 18 h and cooled to 23° C. The mixture was poured on a chilled (0° C.) aqueous concentrated HCl (60 mL) solution (the internal temperature of the resultant aqueous mixture was kept under 50° C.). The solution was extracted using IPAC (3×50 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure. Chromatographic purification (15 g silica gel, 10-50% EtOAc/Hexanes) of the residual material yielded (S)-2-mercapto-2,3-dimethylbutanamide. Chiral GC of butanamide intermediate: 80.6% ee.
[0078] Aqueous concentrated HCl (30 mL) was warmed to 85° C. under an atmosphere of nitrogen. (S)-2-Mercapto-2,3-dimethylbutanamide was added as a solid and the mixture was stirred for 24 h. The solution was cooled to 23° C. and extracted using IPAC (3×20 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure. Chromatographic purification (15 g silica gel, 10-40% EtOAc/Hexanes) of the residual material yielded 1.41 g (59%) of the title compound. 1 H NMR (400 MHz, CDCl 3 ) δ 2.25 (septaplet, 1H, J=4 Hz), 2.22 (s, 1H), 1.43 (s, 3H), 1.09 (d, 3H, J=4 Hz), 0.98 (d, 3H, J=4 Hz); 13 C NMR (100 MHz, CDCl 3 ) δ 181.5, 53.9, 36.4, 20.2, 18.2, 17.3; IR (neat): 2968, 2877, 1693, 1404, 1276, 1110, 925 cm −1 ; Exact Mass (C 6 H 12 O 2 S+Na): calculated=171.0450, measured=171.0449. [α] D at 23° C. and 26.0 g/L in CDCl 3 =+3.18. M=78-80° C.
Example 4
Preparation of SS-2-(bicycle[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (7)
[0079] (S)-2-Mercapto-2,3-dimethylbutanoic acid (1.5 g, 0.01 mol) was dissolved in toluene (15 mL) under an atmosphere of nitrogen. Activated 3A sieves (1.5 g) and MeSCN (1.1 mL, 0.015 mol) were added and the resultant mixture was warmed to 110° C. The mixture was stirred for 2 h and cooled to 23° C. The mixture was treated with saturated aqueous NaHCO 3 (20 mL), the phases were separated and the aqueous phase was extracted with EtOAc (3×15 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure. Chromatographic purification (10 g silica gel, 20-30% EtOAc/Hexanes) of the residual material yielded (S)-5-isopropyl-5-methyl-2-(methylthio)thiazol-4(5H)-one. This material was dissolved in MeOH (15 mL) and (S)-exo-aminonorbornane (1.35 g, 0.015 mol, 99.3% ee) was added under an atmosphere of nitrogen. The solution was stirred for 4 h and concentrated. Chromatographic purification (10 g silica gel, 10-40% EtOAc/Hexanes) of the residual material yielded 1.73 g (64%) of the title compound. 1 H NMR (400 MHz, CDCl 3 , 90.15/9.85 mixture of diastereomers, signals for the major diastereomer) δ 3.33-3.40 (m, 1H), 2.36-2.45 (m, 2H), 2.21 (septaplet, 1H, J=8 Hz), 1.84-1.91 (m, 1H), 1.60-1.83 (m, 1H), 1.42-1.68 (m, 3H), 1.62 (s, 3H), 1.13-1.30 (m, 4H), 1.05 (d, 3H, J=8 Hz), 0.90 (d, 3H, J=8 Hz); 13 C NMR (100 MHz, CDCl 3 , 90.15/9.85 mixture of diastereomers, signals for the major diastereomer) δ 191.1, 180.9, 70.9, 59.5, 43.0, 38.5, 35.9, 35.7, 35.6, 28.2, 26.6, 25.6, 19.0, 18.4; IR (neat): 3168, 2959, 2869, 1696, 1585, 1440, 1327, 1256, 1090, 1017, 829 cm −1 ; Exact Mass (C 14 H 22 N 2 OS+H): calculated=267.1526, measured=267.1525. Chiral LC: 90.15/9.85 dr.
[0080] In another embodiment, synthesis of the target 5-substituted aminothiazolones is achieved via the asymmetric hydrocyanation of 3-methyl butane-2-one (1) to afford a cyanohydrin which is hydrolyzed to the corresponding acid (4), as shown in Scheme 2 below. Activation of the carboxylate group followed by reaction of the resultant acyl chloride with S-exo norbornylthiourea and intramolecular cyclization of the adduct under basic conditions afforded 5S-2-(bicycle[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one as the product.
[0000]
Example 5
Preparation of (S)-2,3-Dimethyl-2-(trimethylsilyloxy)butanenitrile (b)
[0081] TMSCN (28.8 g, 0.29 mol) and N,N-dimethylaniline oxide (0.2 g, 0.0015 mol) were dissolved in THF (75 mL) and the resultant solution was stirred for 1 h at 23° C. under an atmosphere of nitrogen. 3-Methylbutan-2-one (50.0 g, 0.58 mol) was added via syringe and the mixture was cooled to −30° C. 2-((E)-((1R,2R)-2-((E)-5-bromo-2-hydroxybenzylideneamino)-1,2-diphenylethylimino)methyl)-4-bromophenol (1.67 g, 0.0029 mol) and triethylaluminum (0.33 g, 0.0029 mol) were added and the reaction mixture was stirred for 24 h. The mixture was warmed to 23° C. and concentrated (30 mmHg). The residue was distilled under reduced pressure (30 mmHg, 80° C.) to yield 45.6 g (85%) of the title compound. 1 H NMR (400 MHz, CDCl 3 ) δ 1.86 (septaplet, 1H, J=4 Hz), 1.53 (s, 3H), 1.04 (d, 3H, J=4 Hz), 1.02 (d, 3H, J=4 Hz), 0.25 (s, 9H); 13 C NMR (100 MHz, CDCl 3 ) δ 121.5, 73.4, 39.1, 26.0, 17.1, 16.9, 1.15; IR (neat): 2969, 1375, 1254, 1160, 992, 841, 755 cm −1 ; Exact Mass (C 9 H 19 NOSi+Na): calculated=208.1128, measured=208.1129. [α] D at 23° C. and 17.0 g/L in CDCl 3 =−12.13. Chiral GC: 87.28% ee.
Example 6
Preparation of (S)-2-hydroxy-2,3-dimethylbutanoic acid (c)
[0082] Aqueous concentrated HCl (50 mL) was warmed to 85° C. under an atmosphere of nitrogen. (S)-2,3-Dimethyl-2-(trimethylsilyloxy)butanenitrile (5.0 g, 0.027 mol) was added and the mixture was stirred for 12 h. The solution was cooled to 23° C. and extracted using IPAC (3×50 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure. Chromatographic purification (30 g silica gel, 10-50% EtOAc/Hexanes) of the residual material yielded 1.75 g (49%) of the title compound. 1 H NMR (400 MHz, CDCl 3 ) δ 2.02 (septaplet, 1H, J=8 Hz), 1.44 (s, 3H), 1.00 (d, 3H, J=8 Hz), 0.93 (d, 3H, J=8 Hz); 13 C NMR (100 MHz, CDCl 3 ) δ 182.1, 77.1, 35.5, 23.3, 17.2, 15.8; IR (neat): 3433, 2973, 2882, 1725, 1460, 1377, 1247, 1164, 1120, 1045, 948, 855, 737 cm −1 ; Exact Mass (C 6 H 12 O 3 +Na): calculated=155.0678, measured=155.0679. [U] D at 23° C. and 17.0 g/L in CDCl 3 =+2.83. Chiral GC: 87.34% ee (measure using corresponding ethyl ester). MP=47-49° C. X-ray Crystal Structure Image of salt of (R)-2-hydroxy-2,3-dimethylbutanoic acid and R-α-methylbenzylamine is appended.
Example 7
Preparation of 5S-2-(bicycle[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (d)
[0083] (S)-2-hydroxy-2,3-dimethylbutanoic acid (0.3 g, 0.0023 mol) was dissolved in DMF (1.5 mL) and 2-MeTHF (4.5 mL) under an atmosphere of nitrogen. POOMeCl 2 (0.34 g, 0.0023 mol) was added via syringe and the solution was stirred at 23° C. for 2.5 h. (S)-exo-Norbornylthiourea (0.27 g, 0.0016 mol, 99.2% ee) was added as a solid to the solution. iPr 2 EtN (0.84 mL, 0.0046 mol) was immediately added dropwise via syringe and the resultant mixture was stirred for 12 h. The mixture was treated with saturated aqueous NaHCO 3 (10 mL), the phases were separated and the aqueous phase was extracted with EtOAc (3×15 mL). The combined organic phases were washed with brine, dried (Na 2 SO 4 ) and concentrated under reduced pressure. Chromatographic purification (5 g silica gel, 10-30% EtOAc/Hexanes) of the residual material yielded 0.28 g (66%) of the title compound. 1 H NMR (400 MHz, CDCl 3 , 90.8/9.2 mixture of diastereomers, signals for the major diastereomer) δ 3.33-3.40 (m, 1H), 2.36-2.45 (m, 2H), 2.21 (septaplet, 1H, J=8 Hz), 1.84-1.91 (m, 1H), 1.60-1.83 (m, 1H), 1.42-1.68 (m, 3H), 1.62 (s, 3H), 1.13-1.30 (m, 4H), 1.05 (d, 3H, J=8 Hz), 0.90 (d, 3H, J=8 Hz); 13 C NMR (100 MHz, CDCl 3 , 90.8/9.2 mixture of diastereomers, signals for the major diastereomer) δ 191.1, 180.9, 70.9, 59.5, 43.0, 38.5, 35.9, 35.7, 35.6, 28.2, 26.6, 25.6, 19.0, 18.4; IR (neat): 3168, 2957, 1696, 1587, 1440, 1327, 1256, 1090, 1017, 834 cm −1 ; Exact Mass (C 14 H 22 N 2 OS+H): calculated=267.1526, measured=267.1525. Chiral LC: 90.8/9.2 dr. | The invention provides two process for synthesizing substituted aminothiazolone compounds as inhibitors of 11-β-hydroxy steroid dehydrogenase type 1. The processes allow the stereoselective synthesis of the desired compounds without the use of stoichiometric amounts of chiral catalysts. | 2 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part of pending application Ser. No. 06/374,176 filed by me May 3, 1982 entitled "Novel Construction Assemblies", now abandoned.
This invention relates to buildings and particularly to buildings of the type having the outer walls and roof made of corrugated metal, and provides an improved construction for buildings of this type in which a heat-insulating cover is located outwardly of the metal wall and roof and the enclosed corrugated channels are arranged for the passage of ventilating air there through and exhausting to the atmosphere through a linear wind powered eductor mounted as a vent cap along the ridge line of the roof.
In buildings having the external side walls and roof made of corrugated metal, the relatively high thermal conductivity of the metal usually permits such a rapid transfer of heat from or to the interior of the building as to materially affect the usefulness of the building. In the summer season, and throughout the year in the sun belt, the hot sun shining on the building can raise the surface temperature of the metal to 190° F. and requires either excessive internal insulation or high energy costs to maintain a comfort reading of 75° F. inside the building. In addition, not many people would choose to live in a house with exposed outer corrugated metal walls and roof.
OBJECTS OF THE INVENTION
The present invention overcomes these disadvantages, and provides an improved construction for metal buildings in which a heat-insulating blanket is installed and held in place between the external cosmetic cover and the outer surface of the external corrugated metal walls and roofing, and these objects are delineated as follows:
1. The heat-insulating blanket shields the metal walls and roofing from the sun and prevents excessive temperature build-up.
2. The heat-insulating blanket also serves as a galvanic break between dissimilar metals for the application of aluminum siding or roofing as a cosmetic cover over the corrugated walls and roofing.
3. Application of the insulating blanket and cosmetic cover create ventilating channels within the finished external walls and roofing.
Since brick is considered to be a cosmetic material as well as being a poor heat conductor, another object of this invention is to use brick veneer for the outer walls against and attached to the corrugated metal, thus protecting the metal against solar heat build-up and creating ventilating channels for the circulation of cooling air through the structure and without need for the heat-insulating blanket.
Still another object of this invention is the arrangement and interconnection of the ventilating air channels so that ambient air enters along the lower extremity of the walls and along the eave line of the roof and flows upward due to heating and expansion of the air columns within the channels and exhausts to the atmosphere through the vent cap installed along the apex of the roof.
As another object of this invention, the vent cap is designed as a wind-powered linear air eductor connected to the ventilating channels within the roof and external walls and arranged to exhaust air from said channels when the wind blows from either direction.
One other object of this invention is the adaptation of this system to provide a new insulated and ventilated roof installed as a retrofit unit over an existing shingled or other type of roof enclosing an attic space and is arranged to exhaust air upwardly from the attic space as well as through the ventilating channels external to the existing roof.
Until such time as nonflammable furnishings are perfected, it will not be possible to prevent the starting of fires in hotel rooms, apartments and residences, but it is an object of this invention to prevent the spread of such a fire beyond the point of origin by utilizing fireproof construction materials and encapsulating all flammable insulation within the structure.
In addition to the built-in-place air eductor that is an integral part of roof and wall ventilating system, a final object of this invention is to provide a completely assembled wind-powered ridge vent eduction unit that can be installed and nailed in place by the homeowner to exhaust air from the attic space. Heated air will rise naturally and exit through the eduction unit, but during cold weather the wind-powered eduction unit will maintain sufficient air flow through the attic space to prevent the condensation of moisture and consequent dripping of water within the attic space.
SUMMARY OF THE INVENTION
This invention can be summarized as an improvement in metal buildings whereby the living quarters inside are superinsulated and fireproofed, the external metal surface of the corrugated walls and roof is covered with a heat-insulating blanket and cosmetic siding and roofing thus creating air channels there through which are connected to a wind-powered air eductor installed as a vent cap along the roof gable and arranged to exhaust air hrough the walls, roofing and attic space when the wind blows from either direction. In addition, of course, convection air currents will rise as the internal air space is heated by solar energy above the temperature of the external environment and this heated air will also exit through the vent cap.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged cross-section of the roof gable shown in FIG. 3 and illustrates the mechanics of the wind-powered air eductor and the arrangement for the eduction of air from air channels and attic space.
FIG. 2 is an isometric view of a corrugated metal sheet and illustrates the location of inner and outer channels when installed within the external walls and roofing.
FIG. 3 is a vertical cross-section through a house and shows the metal building with corrugated metal walls and roofing, the super insulated and fireproofed interior, and the cosmetic covering external to the corrugated metal walls and roofing. The cooling air channels are shown as well as the direction of air flow through the structure.
FIG. 4 is a plan view cross-section of the external wall disclosed in FIG. 3.
FIGS. 5, 6 and 7 illustrate fabrication and assembly details of the wind-powered eduction unit arranged for retrofit installation or new roof construction.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings and more particularly to FIG. 1 which illustrates the principles of fluid mechanics utilized in my invention for primary and secondary vacuum eduction of air from ventilating channels 15 and 16 and attic space 17 into the wind stream 24 entry 25 and exit 26. Since the design is a mirror image when viewed from the center line, the wind stream force diagram 24 will be reversed when the wind 25 blows from the opposite direction. Implementation of my design is as follows: Opposing corrugated metal sheets 10 are abutted at the roof gable line and are attached either to existing roofing 11 for a retrofit application or to supporting members 50 for new construction. The baffle plate 14 is attached along the apex to opposing corrugated metal sheets 10. The baffle plate 14 has a three-fold function: (1) creates an annular air space 12 that is common to air channels 15 and 16 as well as the attic air space 17; (2) serves as a deflector to divert the ar stream 25 upward as shown in the air stream force diagram 24, and (3) diverts wind-driven rain into air channel 16 for gravity flow off the building, thus preventing entry into the attic space through air passage 17. Next, the heat-insulating blanket 20 and the aluminum roof 30 are installed and spaced apart from the baffle plate 14 to form identical eductor slots 13 on each side of the roof E. The vent cap 35 is installed and spaced apart from the baffle plate 14 by using screws 37 and spacers 36. Any increase in the thickness of the heat-insulating blanket 20 will be compensated by increasing the length of the spacers 36 by a corresponding amount.
Now, in operation, the wind stream force diagram 24 is utilized to show the direction and location of the air stream through the assembly, divergence of lines indicate a decrease in velocity of the air stream as at the exit 26, and convergence of lines indicate an increase in air velocity as at the entry 25. Thus wind blowing into the venturi-throated entry 25 is compressed causing some increase in velocity for more efficient vacuum. Eduction of air from the channels 15, 16 and 17 through the eductor slot 13 and into the air stream 24 is deflected upward by striking the baffle plate 14 and then is forced abruptly downward by the under surface of the vent cap 35 causing the effect of aerodynamic lift with consequent negative air pressure below the air stream and secondary eduction of air from channels 15, 16 and 17 through the eductor slot 13 and into the air stream 24 on the exit side 26 of the assembly.
FIG. 2 is an isometric view of the corrugated metal 10 and is shown to identify the orientation of channels 15 and 16.
FIG. 3 is a cross-sectional view through a metal building having corrugated metal roofing 10 and external walls 10. Fireproof interior finish of the building is as follows: after installation of metal framing for doors and windows, the wall cavity 45 is filled flush with the interior surface of the framing members 52 with sprayable urethane foam having an R-value of 25 for a 31/2" thickness. Firegrade gypsum board 47 is attached to wall framing members 52 and completes the internal wall. Since more space is available within the attic, a cheaper and less efficient fiberglass insulation 46, requiring a 10-inch thickness for a R-value of 40, is used for the ceiling to attic closure. Firegrade gypsum board 47 is installed at the ceiling line and plywood flooring 48 is installed above to encapsulate the fiberglass insulation 46. For the exterior wall, brick is installed in the conventional manner and anchored to the outer face of the corrugated metal wall with weepholes arranged in the first brick course for egress of condensation and entry of cooling air 18 which rises as the temperature increases within the wall and exits through air channels 16 into the soffit and attic space above. The soffit enclosure 55 and fascia 56 seal the eave and the roof drain 57 is shown in position for attachment to the fascia 56. Cooling air also enters the soffit area through air channels 15 along the underside of the corrugated roofing 10 at the eave line and solar induced heating within the attic space causes rising air currents 15, 16 and 17 throughout the structure which continue to rise and exit the building as long as the air temperature within the attic is above the temperature of outside ambient air. When the wind blows, additional air is pumped through the structure as already described and, in addition, through the air channel 16 for a new roof installation and through both air channels 15 and 16 for a retrofit installation for direct cooling of wall and roofing corrugated sheets 10.
FIG. 4 is a plan sectional view of the wall shown in FIG. 3 and illustrates the usage of the corrugated metal wall 10 for fireproof containment of urethane insulation 45 as the inner wall sealed with firegrade gypsum board 47, and the arrangement of the brick 40 outer wall with enclosure of the air channels 16 for the passage of cooling air upward through the structure.
FIG. 5 is a combined cross-section and elevation of the wind-driven eductor assembly along the centerline 67 and shows the outer cover 70 with the standing seam 69 on the outer extremity and the ear section 71 folded down to connect the inner cover 72 having a series of ventilating slots 73 and held in place with installation nails 75.
FIG. 6 is a combined cross-section and elevation of the lower cover 72 along the centerline 67 and shows the arrangement of the perforated slots 73 for the passage of vacuum educted air there through.
FIG. 7 is a cross-sectional view and shows the wind-driven eductor of FIGS. 5 and 6 mounted on the roof 11 gable wherein the roof slope may vary from a 12/12 slope 65 to a 3/12 slope 66 and is held in place with nails 75. Entry wind 25 blows into the unit between the outer cover 70 and the inner cover 72 and is confined generally within the limits of the force diagram 24 being deflected upward by the inner cover 72 to the apex at the centerline 67 and then downward by the outer cover to the wind exit 26. The confined wind flow thus described through the unit causes direct eduction of attic air 17 through slots 73 into the windstream 24 on the entry side 25 and indirect eduction of attic air 17 through the slots 73 due to the airplane wing lift effect and consequent negative pressure area on the wind exit side 26. The eductor unit is constructed as a mirror image about the centerline 67 and a reversal of wind direction will change FIG. 7 from a left-hand thumb entry as shown to a right-hand thumb entry; i.e., a mirror image.
While the preferred embodiment of the invention has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims. | A ventilated wall and roofing having walls and roofing with vertically inclined channels there through and connected along the roof apex to a wind-powered linear vent cap arranged for primary eduction of air from said channels through slots on the entry side of said vent cap and secondary eduction of air from said channels through slots on the exit side of said vent cap when the wind blows from either direction. | 4 |
FIELD OF THE INVENTION
The invention relates to orthopaedic implants and more particularly an adjustable bone screw having a rotationally ratcheting mechanism for compressing and clamping a patient's bone tissue.
BACKGROUND OF THE INVENTION
Bone screws are utilized in a variety of medical procedures to take advantage of the natural anchoring properties of bone tissue. Such procedures often involve fastening multiple bone fragments of a bone fracture together, or mounting one or more prosthetic elements to the bone in an effort to improve patient mobility. Bone plates are often also utilized in cooperation with a bone screw to provide a more distributed area of compression against the bone being clamped.
The classical bone screw construction comprises an integrally formed fastener having at one end a threaded shaft of a predetermined length to penetrate the bone to a predetermined depth and a fixed radial head formed with a compression flange disposed at the opposite end. In operation, a physician first determines the proper size of bone screw to install from an array of stocked sizes. Once the appropriate size is selected, the screw is implanted into the bone by drilling the threaded end of the bone screw into the bone, for example, across a bone fracture, and utilizing the head as a clamping element.
While the classical bone screw design works well for its intended uses, different orthopedic applications typically require differently sized bone screw shafts or heads in order to adequately anchor or provide proper compression. Consequently, due to the integral nature of the classical bone screw, treatment centers often must stock an assortment of differently sized bone screws in preparation for any type of bone screw application. This tends to create substantial up-front procurement costs to either the supplier or user institution. Moreover, because the classical screw length is fixed, the surgeon must undertake a fairly accurate pre-implant measurement to properly determine the appropriate sized bone screw. Should the measurement prove less than satisfactory, the head may project beyond the expected compression point, requiring removal and replacement of the screw.
In an effort to solve the problems described above, one proposal for a bone screw, disclosed in U.S. Pat. No. 5,628,752 to Asnis et al., implements a two-piece structure including a shaft formed with bone thread at its proximal end and a nut. The shaft is formed with a plurality of axial in-line teeth projecting angularly toward the shaft proximal end. The nut is complementally formed to slide axially along the shaft in the direction of the proximal end and includes an inwardly projecting radial tab or pawl that prevents axial backing-out of the nut by engaging the previously passed tooth. In operation, the screw shaft is drilled into the bone tissue and the nut advanced axially along the shaft until adequate compression between the screw and the nut is obtained. Any excess shaft projecting beyond the nut is typically cut. As a result, the bone screw is adaptable to a variety of bone screw applications due to its variable length.
A second proposal, disclosed in U.S. Pat. No. 5,167,664 to Hodorek, utilizes a similar linear ratcheting feature by including a screw shaft formed with circumferential external teeth. The teeth engage circumferential internal grooves formed within a head to effect unidirectional axial adjustment. Operation of the Hodorek device is similar to that of the Asnis device.
Although the proposals described above work well to minimize the aforementioned problems inherent in a classical type of bone screw, the linear ratcheting feature is incapable of interfacing with conventional surgical power tools. Because of this problem, implanting a bone screw of the linear ratcheting construction often involves more effort and time on the part of the physician. Moreover, non-conventional tooling capable of interfacing with a linear ratcheting bone screw is often substantially more costly than readily available conventional tools.
Thus, the need exists for a bone screw capable of rotationally ratcheting to allow a convenient interface with conventional surgical power tools. The need also exists for a uniform bone screw construction to maximize the reduced costs inherent with wholesale purchasing. The bone screw of the present invention satisfies these needs.
SUMMARY OF THE INVENTION
The present invention provides the capability of rotationally ratcheting an adjustable bone screw head with respect to an anchored shaft to modify the bone screw length and adapt to a variety of bone screw applications. By implementing such a feature, conventional surgical power tools may be employed to aid a physician during the implant procedure. Further, the costs involved in ordering and stocking a variety of differently sized parts are significantly reduced due to the inherent advantages involved in wholesale buying. Moreover, implanting an adjustable bone screw according to the present invention allows adjustment to intraoperative changes and improper pre-operation sizing, substantially reducing the incidence of bone screw removal and replacement.
To realize the advantages above, in one form the invention comprises a rotationally ratcheting bone screw including a body having a distal end formed with an engagement tip for engaging bone tissue, and a shaft formed with a unidirectional stop. The bone screw further includes a fastening element formed with an opening complementally configured to receive the shaft and responsive to relative rotation between the shaft and fastening element to axially advance along the shaft. The fastening element includes a rotationally sensitive ratchet element to cooperate with the stop and inhibit relative counter-rotation between the shaft and the fastening element.
In another form, the invention comprises a rotationally ratcheting bone screw kit comprising a set of disassembled components. The components include a body having a distal end formed with an engagement top for penetrating into bone tissue, and a shaft formed with a unidirectional stop. A fastening element is formed with an opening complementally configured and adapted to receive the shaft when assembled and responsive to relative rotation between the shaft and fastening element to axially advance along the shaft. The fastening element includes a rotationally sensitive ratchet element to cooperate with the stop and inhibit relative counter-rotation between the shaft and the fastening element.
In yet another form, the invention is directed to a rotationally ratcheting bone screw system including a body having a distal end formed with an engagement tip for penetrating into bone tissue, and a shank formed with a unidirectional stop. A fastening element is formed with an opening complementally configured to receive the shaft and responsive to relative rotation between the shaft and fastening element to axially advance along the shaft. The fastening element includes a rotationally sensitive ratchet element to cooperate with the stop and inhibit relative counter-rotation between the shaft and the fastening element. Also included in the system is an elongated tubular installation instrument for percutaneous insertion and torquing of the assembled bone screw and fastening element and having an internal configuration complementally formed to fit around the fastening element to effect torquing thereof.
Other features and advantages of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a bone screw according to one embodiment of the present invention;
FIG. 2 is an exploded perspective view similar to FIG. 1
FIG. 3 is an axial cross-sectional view along line 3--3 of FIG. 2;
FIG. 4 is a radial cross-sectional view along line 4--4 of FIG. 3;
FIG. 5 is a radial cross-sectional view similar to FIG. 4; and
FIG. 6 is a soft tissue tensioner according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, the bone screw of the present invention generally designated 10, includes an elongated shaft 20 that cooperates with a fastening element 40 to permit unidirectional rotation while inhibiting relative counter-rotation between the shaft and the fastening element. This construction allows for installation of a predetermined length shaft while allowing a variety of screw lengths.
With reference to FIGS. 1, 2, 3 and 5, the bone screw shaft 20 includes a distal end 22 formed with standard "oversized-in-diameter" right-hand bone threads 24 for penetrating and anchoring into bone tissue. Formed adjacent to the bone thread and extending radially and axially along an intermediate portion 26 of the shaft are external right-hand threads 28 for engaging the fastening element 40. A step-shaped groove 30 is formed axially along the surface of the shaft and includes an oblique flat 32 terminating in a radially directed wall 34 to define a unidirectional radial stop.
Referring to FIGS. 1, 3 and 4, the fastening element 40 includes a multi-piece construction comprising a spool-shaped head 42 and a clip-in ratchet element 70. The head includes a hub 44 (FIG. 3) having a flat portion 46 (FIG. 1) and positioned centrally between respective oppositely disposed flanges 48 and 50 to define a drop-center 52. The respective flanges are formed with inwardly confronting grooves 54 and 56 (FIG. 1) adjacent to and aligned in parallel with the flat portion 46 of the hub to define a slot 58 (FIG. 4). One of the flanges 48 includes a formed peripheral flat 49 to assist in torquing the head. A throughbore 60 is formed centrally through the hub and includes formed right-hand threads 62 configured to threadably receive the intermediately disposed shaft threads 28. A tooth passage (not shown) is formed between the throughbore and the drop-center. In an alternative embodiment, the head 42 is mounted to a bone plate 43 (shown in phantom, FIG. 3) having a bore axially aligned with the head throughbore 60. This is especially useful for plate fixation.
With reference to FIGS. 1 and 4, the ratchet element 70 comprises an integrally formed semi-circular clip configured to complementally nest in the hub drop-center 52. The clip is formed of a resilient material and includes a first end 78 shaped radially inwardly to engage the head slot 58. The second end includes an oversized-in-cross-section tooth 80 having a pointed tip 82 projecting radially inwardly at 84, and in confronting relations to the end 78. The tooth projects through the tooth passage and impinges on the outer radius of the shaft intermediate threads 28. To prevent the clip from flexing beyond a predetermined angle, a support 86 is formed along the interior faces of the flanges 48 and 50.
As an aid in manipulating the fastening element 40 along the shaft 20, an installation instrument is included in a bone screw system of the present invention, generally designated 90, and shown in FIG. 2. The instrument includes a hollow cylindrical socket 92 having a formed flange 94 to complementally engage the head flat 49. A multi-flat fitting 96 projects axially from the socket to permit straightforward torquing of the head.
Manufacture, assembly and packaging of the bone screw 10 of the present invention may be carried out according to acceptable component fabrication practices well known to those skilled in the art. The flexibility in the design of the present invention allows for a variety of packaging schemes to fit the supply needs of the medical industry. For example, the bone screw components may be pre-assembled and packaged together as a unit, or packaged as a kit of unassembled components, or even packaged and sold separately as individual components.
In operation, the bone screw of the present invention adapts to a variety of internal and external fixation applications. Generally, the procedure begins with the physician making necessary incisions to provide adequate access to predetermined bone tissue defining a desired anchoring point. Because of the convenient adjustability of the fastening element 40 with respect to the shaft 20, preliminary measurements and calculations performed by the physician to estimate an exact shaft size for installation are substantially minimized. As a result, the procedure continues by inserting the bone screw 10 through the prepared access area, and drilling the distal threaded end of the shaft into the bone tissue to a predetermined depth with a suitable drill as is well known in the art.
Once the shaft 20 attains the desired depth within the bone tissue, the fastening element 40 is then rotated onto the shaft intermediate threads 28 in a clock-wise manner. Because the tip 82 of the ratchet element 70 rides the shaft radial periphery, each full 360 degree rotation results in an audible "click", signaling engagement of the ratchet tooth 80 with the axial groove 30. The head is rotated and advanced along the shaft until the outboard face of the flange 50 touches the surface of the bone. At this point, the physician continues rotation of the head to the next "click" to position the tooth in engagement with the groove and maintain the bone screw in compression with the bone tissue.
In compression, the fastening element 40 is constantly urged axially toward the proximal end of the shaft 20. With the ratchet element 70 left in engagement with the groove 30, the compression tends to slightly counter-rotate the ratchet element, causing the ratchet top 82 to abut the radially projecting wall 34 of the groove. Once this occurs, the ratchet element is effectively stopped from counter-rotating any further. This effect is translated to the end 78 which exerts an inhibiting force on the head 42 to prevent any further counter-rotation thereof. Once the head is successfully positioned, the excess length of the shaft may be selectively cut and removed, or connected to an external fixator.
Referring now to FIG. 6, a second embodiment of the present invention, generally designated 100, comprises a soft tissue tensioner and includes many of the features of the first embodiment such as a shaft 102 and a fastening element 104. The fastening element construction is identical to that of the first embodiment and warrants no further description. However, the shaft is modified to include an interface 106 for capturing soft tissue, rather than a bone screw thread.
In operation, for example during a procedure to tension an ACL 108 at a tibia 110, the shaft is attached to the distal end of the ACL and then inserted through a drill hole in the tibia. The lower end of the shaft projects through the lateral cortex. The fastening element 104 is then advanced onto the shaft and rotated about the shaft threads until it contacts the cortex. Further rotation of the fastening element draws the shaft axially through the drill hole towards the fastening element, thereby tensioning the ACL. During the process, the shaft, and thus the ACL, is restricted from rotating either by friction against the inner surface of the drill hole, or by manual control. The ratcheting feature of the present invention prevents reverse rotation of the shaft relative to the fastening element which would undesirably cause subsequent loosening of the ACL.
Those skilled in the art will appreciate the many benefits and advantages of the present invention. Of significant importance is the rotationally ratcheting feature of the present invention that allows a uniformly sized bone screw or soft tissue tensioner shaft to adapt and adjust to a variety of dimensional treatment situations. This feature reduces inventory costs by reducing the number of bone screw lengths. Moreover, because of its rotational nature, the present invention is particularly suited for interfacing with convenient surgical power tools. This minimizes the effort, time and costs experienced by physicians in implanting bone screws.
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. For example, while a significant portion of the foregoing disclosure relates to the field of bone screws, it is to be understood that the rotationally ratcheting construction may be extended to any fastening application. | A rotationally ratcheting bone screw including a body having a distal end formed with an engagement tip for engaging bone tissue, and a shaft formed with a unidirectional stop. The bone screw further includes a fastening element formed with an opening complementally configured to receive the shaft and responsive to relative rotation between the shaft and fastening element to axially advance along the shaft. The fastening element includes a rotationally sensitive ratchet element to cooperate with the stop and inhibit relative counter-rotation between the shaft and the fastening element. | 0 |
This is a divisional of application Ser. No. 09/096,884, filed on Jun. 12, 1998 now U.S. Pat. No. 6,014,804.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a low-voltage electromagnetic riveting apparatus and method, and more particularly to a method and apparatus for controlled and efficient low-voltage electromagnetic riveting.
2. Background Information
Riveting machines are well known and in wide use throughout the aerospace industry, as well as in other industries. Rivets provide the best known technique for fastening an aerodynamic skin to a frame to provide a strong, aerodynamically smooth surface. Rivets are also used in the interior structure of an aircraft, since they are the lightest and least expensive way of fastening structural components together.
One form of riveting uses a low voltage electromagnetic riveting (LVEMR) system 100 , as shown in FIG. 1 . The LVEMR system 100 provides a controlled amount of energy in a single pulse and is typically smaller and less cumbersome than a pneumatic or hydraulic system. Further, the LVEMR system has almost no mass so it only has nominal reactionary forces. The LVEMR system 100 shown in FIG. 1 incorporates two electromagnetic actuators, a first actuator 101 and a second actuator 112 , which are positioned on opposite sides of first and second workpieces 114 and 115 , respectively. The first and second work pieces 114 and 115 are sandwiched together and a hole has been drilled through them to accommodate a rivet 93 . The first and second actuators 101 and 112 each include a body 116 in which is positioned a driver 118 and a coil 120 . A rivet die 92 is coupled to the driver 118 and is forced against the rivet 93 . Also, there may be a recoil mass 123 which is typically secured to a rear surface of the coil 120 . Extending from the recoil mass 123 is an air cylinder rod 124 , which extends out of the body 116 into a two-chamber air cylinder 126 . Associated pressure relief valves and other control elements are shown diagramatically as block 128 . The elements of block 128 are responsible for initially positioning the driver 118 and its rivet die 92 against a head of the rivet 93 .
Power is supplied to the system 100 by means of a power supply 130 . A DC output from the supply 130 is used to charge a bank of capacitors in circuit 132 to a selected voltage. The voltage selected is based on the force necessary to accomplish the desired riveting task. The circuit 132 includes an electronic switch positioned between the capacitors and the coil 120 .
A trigger signal from a firing circuit 134 activates the electronic switch, dumping the charge of the capacitor bank in circuit 132 into the coil 120 . A current pulse is induced into the coil 120 causing strong eddy currents in a copper plate 119 located at the base of the driver 118 . This creates a very strong magnetic field that provides a repulsive force relative to the coil 120 . The driver 118 is propelled forward with a large force causing the rivet die 92 to upset the head of the rivet 93 . A more detailed discussion of low voltage electromagnetic riveting can be found in U.S. Pat. No. 4,862,043, which is incorporated herein by reference.
Once the LVEMR system 100 has upset the rivet 93 , a fastened assembly 140 is created as shown in FIG. 1 B. The assembly 140 includes a deformed rivet 146 , having a head 142 and a tail 154 . The hole drilled into the first and second workpieces 114 and 115 includes a countersink 148 drilled into the second workpiece 115 to receive the head 142 of the deformed rivet 146 .
Unfortunately, the fastened assembly 140 , when produced by the LVEMR system 100 described above, has significant gaps 150 between the head 142 of the deformed rivet 146 and the countersink 148 . The gaps 150 are undesirable since they could lead to early corrosion of the deformed rivet 146 , causing it to weaken and prematurely fail. Accordingly, for the foregoing reasons, there is a need in the art for a controlled low-voltage electromagnetic riveting apparatus and process that mitigates the gaps 150 between the rivet head 142 and the countersink 148 .
SUMMARY OF THE INVENTION
In one aspect, the present invention is directed to a method for minimizing undesirable gaps in riveted assemblies including the steps of selecting a rivet having a head and a tail with identical forming characteristics, positioning the selected rivet in an assembly that is countersunk on one of two sides, and applying a force over time to tile head of the rivet and a force over time to the tail of the rivet that are equal and opposite, compensating for force-unbalancing characteristics of the countersink.
In another aspect, the present invention is directed to a method for mitigating gaps between a deformed head of a rivet and a countersink in an assembly that is coupled by a low-voltage electromagnetic riveter having a head side actuator and tail side actuator. The method includes the steps of selecting a rivet that uniformly deforms at a tail and at a head of the rivet, positioning the volume of the rivet within the assembly such that force applied over time to the head of the rivet by the head side actuator equals a force applied over time to the tail of the rivet by the tail-side actuator.
In yet another aspect, the present invention is directed to a method for mitigating gaps between a head of a rivet and a countersink within a first workpiece of two workpieces when the rivet is upset by a low voltage electromagnetic riveting process. The method includes the steps of extending a tail of the rivet out of a surface of a second workpiece of the two workpieces by a length from 0.9 to 1⅓ times a diameter of the rivet, extending the head of the rivet out of a base of the countersink by a length that is 5% to 10% less than the length the tail of the rivet was extended out of the second workpiece surface, and upsetting the tail of the rivet with a tail die having a shape substantially similar to a shape of the countersink within the first workpiece.
In still another aspect, the present invention is directed to a method for controlled low-voltage electromagnetic riveting of a primary workpiece including a countersink and at least a secondary workpiece with a rivet, having a head, a tail, and a diameter, using a head actuator having a head die to contract the head of the rivet and a tail actuator having a tail die to contact the tail of the rivet. The method includes the steps of selecting the rivet so the rivet is comprised of a homogenous alloy and the rivet has a uniform diameter, positioning the tail of the rivet so that it protrudes from an outside surface of the secondary workpiece by a length from 1 to 1.3 times the diameter of the rivet, positioning the head of the rivet so that it protrudes from the base of the countersink by a length that is 5 to 10 percent less than the length that the tail protrudes from the step of positioning the tail, upsetting the head of the rivet with the head die having a flat contact surface, and upsetting the tail of the rivet with the tail die, wherein the tail die has an upper diameter within 20% of the depth of the countersink, and wherein the tail die has an upper diameter within 10 degrees of the upper angle of the countersink.
In another aspect, the present invention is directed to a low-voltage electromagnetic riveter for controlling the force over time applied to a head and a tail of a rivet within an assembly having a workpiece that is countersunk to receive the head of the rivet. The riveter includes a head and a tail actuator that respectively apply a force over time to the head and the tail of the rivet. Each of the actuators includes a die which contacts the rivet, a coil which creates a repulsive force when electrical current is passed therethrough, a driver physically adjacent to the coil and movable along an axis of the rivet by the repulsive force created by the coil, and a load cell positioned between the driver and the die to measure the force over time applied to a designated end of the rivet. A head current source and a tail current source are electrically connected to the coil of the respective head and tail actuator for supplying a controlled amount of current, and a firing circuit is electrically connected to each of the head current source and the tail current source for controlling phase and magnitude of the controlled amount of current supplied to each of the head actuator and the tail actuator.
In yet another aspect, the present invention is directed to a method for controlled low-voltage electromagnetic riveting. The method includes the steps of monitoring the force applied over time to a head and tail of a rivet during a deformation of the rivet by the low-voltage electromagnetic riveting, adjusting a phase of the force applied to at least one of a location of the head and the tail of the rivet so that the phase of the force applied to the location of the head of the rivet equals the phase of the force applied to the location of the tail of the rivet, and adjusting a magnitude of the force applied to at least one of the location of the head and the tail of the rivet so that the magnitude of the force applied to the location of the rivet head equals the force applied to the location of the tail of the rivet.
In still another aspect, the present invention is directed to a method for mitigating gaps between a deformed head of a rivet and a countersink in an assembly that is coupled by a low-voltage electromagnetic riveter, including a head-side driver, having a first load cell, and a tail side driver, having a second load cell, and a firing control circuit capable of controlling phase and magnitude of force applied by the head-side driver and the tail-side driver. The method includes the steps of positioning a first test rivet within the assembly, monitoring a first output of the first load cell and the second load cell while the first test rivet is upset to determine the phase and the magnitude of the force applied to a head and a tail of the rivet respectively by the head side driver and the tail side driver, comparing the first output of the first load cell and the second load cell that occurred when the first test rivet was upset, and adjusting the phase of one of the force applied by the head driver and the force applied by the tail driver so that the phase of the force applied by the head driver matches the phase of the force applied by the tail driver. The method also includes the steps of positioning a second test rivet within the assembly, monitoring a second output of the first load cell and the second load cell while the second test rivet is upset to determine the phase and the magnitude of the force applied to the head and the tail of the second test rivet respectively by the head side driver and the tail side driver, comparing the second output of the first load cell and the second load cell that occurred when the second test rivet was upset, and adjusting the magnitude of one of the force applied by the head driver and the force applied by the tail driver so that the magnitude of the force applied by the tail driver equals the magnitude of the force applied by the head driver.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present invention will be better understood with regard to the following description, appended claims, and accompanying drawings wherein:
FIG. 1A shows a block diagram of a prior art low-voltage electromagnetic riveting system;
FIG. 1B shows a rivet deformed by the riveting system of FIG. 1A;
FIG. 2 shows a force vs. time graph applied to a rivet during its deformation into a hole having a countersink;
FIG. 3 shows a force vs. time graph applied to a rivet using a process and apparatus for mitigating gaps according to the present invention;
FIG. 4 shows a desired rivet protrusion to mitigate gaps according to a first embodiment of the present invention;
FIG. 5 shows a desired forming die configuration according to the first embodiment of the present invention;
FIG. 6A shows a schematic diagram of a low-voltage electromagnetic driving system according to a second embodiment of the present invention;
FIG. 6B shows a side view of a load cell and driver of the low-voltage electromagnetic driving system of the second embodiment;
FIG. 7A shows a force vs. time graph for a rivet head and rivet tail having applied forces that are out of phase and have different magnitudes;
FIG. 7B shows a force vs. time graph for the rivet head and the rivet tail having applied forces that are in phase but have different magnitudes, and
FIG. 7C shows a force v. time graph for the rivet head and the rivet tail having applied forces that are in phase and have the same peak magnitude.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following process and apparatus assist in controlling and balancing the forces applied to a rivet. Such control mitigates gaps between a head of a rivet and a countersink into which it is deformed. Other advantages include more accurate control over rivet interferences and a reduction in reactive forces applied to an object being riveted.
It has been discovered that to mitigate the gaps between the rivet and the countersink, it is essential to maintain an equal force on the head and a tail of the rivet throughout the riveting process. Unfortunately, when the workpiece or assembly to be riveted has been countersunk to receive a deformed rivet head, simultaneous activation of two opposing LVEMR guns will not produce equal forces on the rivet head and the rivet tail over the duration of time that the rivet is deformed.
Low voltage electromagnetic rivet (LVEMR) guns are typically dynamic and used in an open loop system, as such, they offer no method of “real-time” force control during the rivet-forming process. Because the LVEMR guns are used in an open loop, they produce a dissimilar force on the head and tail over time, as shown in FIG. 2 . However, the forming process can be manipulated to compensate for the force unbalancing effects of a countersink within a workpiece. This manipulation is accomplished by selecting process variables so that the head and tail of the rivet have similar forming characteristics over time as shown in FIG. 3 .
In a first embodiment, as shown in FIGS. 4 and 5, the force-displacement relationship of a head 21 and tail 23 of a rivet 22 are manipulated via the forming characteristics of the rivet 22 to maintain a force balance between the head 21 and the tail 22 .
Five factors typically affect the forming characteristics of the rivet 22 , and therefore can be used to affect the force-displacement relationship of the head 21 and the tail 23 . First, there is the mechanical properties of the rivet 22 , i.e. the stress—strain relation. Since rivets are typically composed of a homogenous alloy, there is no difference in the material adjacent the head 21 and the tail 23 . Therefore, this factor does not create a difference in the force-displacement between the head 21 and the tail 23 . Second, the diameter of the rivet will affect the force-displacement along the rivet 22 . Any difference in force-displacement due to diameter effects between the head 21 and the tail 23 can be eliminated by using a slug rivet, which has a constant diameter throughout.
The third factor affecting the force-displacement relationship of the rivet 22 is the amount of rivet 22 that extends out of the primary sheet 24 and the secondary sheet 26 . This includes a head protrusion 28 of the rivet 22 above a countersink 25 in the primary sheet 24 to be coupled to the secondary sheet 26 , as shown in FIG. 4 . The third factor also includes a tail protrusion 30 from the secondary sheet 26 . The larger the protrusion values for the head protrusion 28 and the tail protrusion 30 , the more the displacement of the protrusion for a given force, i.e., a soft force-displacement relationship.
The fourth factor affecting the force-displacement is the geometry of the countersink 25 , and the fifth factor is the design of a head die 32 and a tail die 34 used to upset the rivet 22 , as shown in FIGS. 4 and 5. Captivating dies, such as the tail die 34 , and deep countersinks, such as the countersink 25 , create a stiffer force-displacement relationship. Therefore, there is less displacement of the rivet 22 for a given force when using dies, such as the tail die 34 , and countersinks, such as countersink 25 , that prevent the material of the rivet 22 from flowing outward when it is upset.
In the first embodiment, a preferred combination of the above-described factors maintains a balanced force, i.e. equal force on the tail 21 the head 23 , throughout the riveting process which results in the elimination of any gaps between the deformed head and the countersink 25 . Referring to FIG. 4, the preferred combination has the amount of head protrusion 28 at a length that is five to ten percent less than the length of the tail protrusion 30 . In other words:
Head Protrusion=(1−[0.05 to 0.10]) (Tail Protrusion).
Further, referring to FIG. 4, the tail protrusion 30 is preferably 0.9 to 1.3 times a diameter 19 of the rivet 22 . In other words:
Tail Protrusion=[0.9 to 1.3] Rivet Diameter.
Referring to FIG. 5, the depth 44 of a contact surface 36 of the tool die 34 in the preferred combination must be similar to, i.e. within 20% of, the depth 42 of the countersink 25 . The contact surface 38 of the head die 32 is preferably flat. Also, an upper diameter 40 of the tail die 34 must be similar to a countersink diameter 37 , i.e. the upper diameter 40 must be within 20% of the countersink diameter 37 . Finally, an upper angle or taper 48 of the edge of the die surface of the tail die 34 must be similar, i.e. to an upper angle or taper 46 of the countersink, i.e. within 20%.
In a second embodiment, the force applied to a head and a tail of a rivet is balanced, i.e applied equally over time, by controlling the rivet upsetting process using a monitoring and application assembly 50 , shown in FIG. 6 A.
When riveting a workpiece that has a countersink, using two rivet guns, one at a head side and the other at a tail side of a rivet 22 , the force applied to the head side is usually out of phase with and has a different magnitude than the force applied to the a tail side of the rivet 22 , as shown in FIG. 7 A. However, the assembly 50 can be used to create the proper differential voltage and timing so that the forces applied to the head and tail side of the rivet 22 are balanced, i.e., the forces applied over time to each side are nearly identical.
The assembly 50 includes a first load-cell 56 , and a second load-cell 58 , used to monitor the force applied by the electromagnetic riveter during the riveting process. Each of the first and second load-cells 56 and 58 is mounted on respective first and second drivers 52 and 54 , near its respective first and second rivet die 60 and 62 . Preferably, each of the first and second load-cells 56 and 58 is positioned no less than three inches from its respective first and second rivet die 60 and 62 .
The first load cell 56 and the second load cell 58 are identical and are described with reference to the first load cell 56 , shown in FIG. 6 B. The load cell 56 includes a piezo-electric quartz cell 66 , preferably a PCB Model 204M device. An integral cable 68 extends from the quartz cell 66 and is coupled to a waveform analyzer 64 , such as a Nicolet Module 2580, which digitally stores the electrical waveform produced by the quartz cell 66 when a force is applied to it. By subjecting the quartz cell 66 to known forces and monitoring the output, a conversion graph can be created, where a particular electrical waveform can be converted to a force-overtime waveform.
As shown in FIG. 6B, the quartz cell 66 is coupled to the driver 56 and the head die 60 , so that it will receive and register at least 95% of the force applied by the driver 56 , yet dampen external noise. Two pieces of tape 70 a and 70 b , preferably Capton tape, are positioned on first and second sides of the quartz cell 66 that are orthogonal to a longitudinal axis of the driver 52 . The two pieces of tape 70 a and 70 b help dampen noise produced by the driver 56 , which could interfere with an accurate measurement by the quartz cell 66 . First and second respective steel washers 72 a and 72 b are respectively positioned adjacent the Capton tapes 70 a and 70 b . The first and second steel washers 72 a and 72 b , as well as the quartz cell 66 , are annular, allowing a stud 74 to pass through. The stud 74 is preferably a copper beryllium threaded stud. Copper beryllium is preferred since it may be threaded to the driver 52 and the head die 60 coupling the two physically yet allowing 95% of the force from the driver 52 to pass through the load cell 56 , instead of the stud 74 . Optionally, a portion 76 of the driver 52 may be threadingly detachable to allow easy maintenance and replacement of the load cell 58 .
The phase and magnitude of the force applied by the first and second drivers 52 and 54 are directly caused by a “charge dump” from a respective first and second capacitor bank 78 and 80 charged by a power cell 82 and controlled by a firing circuit 84 . The firing circuit has a first phase and amplitude voltage control 86 for controlling the phase and magnitude of force, via voltage, of the first driver 52 , and a second phase and amplitude control 88 for controlling the phase and magnitude of force, via voltage, of the second driver 54 .
There are four steps in determining the proper differential voltage and timing delay to balance the forces on the head and tail of the rivet 22 . First, the desired process conditions, i.e. the desired rivet protrusion and die geometry, must be selected The forces are then monitored by the first and second load cells 56 and 58 during the rivet-forming process with no differential voltage and no timing delay, yielding a force-over-time graph as shown in FIG. 7 A. The force over time applied to the rivet 22 is recorded by the waveform analyzer 64 .
Next, the timing delay is adjusted to bring the forces into phase. The forces are in phase when the peak forces are reached simultaneously, as shown in FIG. 7 B. It is important to adjust phase first since amplitude often changes when the phase is changed. For example, in FIG. 7A, the head force has the greatest magnitude, while in FIG. 7B, the tail force has the greatest magnitude. The proper amount of delay is approximately equal to the difference in time between the head and tail peak forces. As shown in FIG. 7A, if the phase difference 60 is 50 μs, where the head force precedes tail force, then the head force should be delayed about 50 μs by adjusting the phase using the first control 86 .
For the third step, the voltages are adjusted to produce equal force magnitude, i.e. the greater force is reduced or the lesser force is increased by changing charge voltage via the firing circuit 84 . In the example shown in 7 B, the tail force needs to be decreased by adjusting voltage amplitude using the second control 88 until the tail force equals head force. It is most desirable if the entire force on the tail and head matches for their duration. However, if this match is not possible, it is important that the force peaks 61 , i.e., the force having the greatest area, as shown in FIG. 7C, are as equal as possible. If the forces cannot be entirely aligned, then they must at least substantially match in this area.
Finally, the second and third steps are repeated until well-matched curves are achieved as in FIG. 7 C.
With the present invention, it is possible to apply an equal force to a rivet head and tail, even when the head is upset into a countersink. By these arrangements, gaps between a deformed head and a countersink can be mitigated and interferences better controlled.
While the detailed description above has been expressed in terms of specific examples, those skilled in the art will appreciate that many other configurations could be used to accomplish the purpose of the disclosed inventive apparatus. Accordingly, it will be appreciated that various equivalent modifications of the above-described embodiments may be made without departing from the spirit and scope of the invention. Therefore, the invention is to be limited only by the following claims. | The present invention relates to a method for minimizing undesirable gaps in riveted assemblies. The method includes the steps of selecting a rivet having a head and a tail with identical forming characteristics, positioning the selected rivet in an assembly that is countersunk on one of two sides, and applying a force over time to the head of the rivet and a force over time to the tail of the rivet that are equal and opposite, compensating for force unbalancing characteristics of the countersink. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority from the U.S. Provisional Patent Application serial number 61/499,513 which was filed on June 21, 2011.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to additives useful for reducing the concentration of hydrogen sulfide in hydrocarbons. The invention particularly relates to additives that are a system of components and their use in hydrocarbons to scavenge hydrogen sulfide.
2. Background of the Art
Hydrocarbons, such as crude oil, may contain acids in several forms. These acids may be mineral acids such as hydrochloric and phosphoric acids. A common inorganic acid found in hydrocarbons is hydrogen sulfide and various oxidized forms of hydrogen sulfide such as sulfuric acid.
Hydrogen sulfide is both toxic and corrosive. Neither of these properties is usually desirable in hydrocarbons.
Hydrogen sulfide may be present when crude oil is produced from an oil well. It may also be present or created by decomposition of other sulfur containing compounds during a refining process. If not removed, generally by scavenging, it may still be present after refining in hydrocarbon products ranging from light lubricating oils to fuels to heavy fuels to bitumen. It would therefor be desirable in the art of producing and refining hydrocarbons to reduce or remove hydrogen sulfide from the hydrocarbons.
SUMMARY OF THE INVENTION
In one aspect, the invention may be a hydrogen sulfide scavenger including a reaction product of glyoxal and a polyamine. The hydrogen sulfide scavenger may also include a dispersant.
In another aspect, the invention may be the product of treating a hydrocarbon with a hydrogen sulfide scavenger wherein the hydrogen sulfide scavenger includes a reaction product of glyoxal and a polyamine.
In still another aspect, the invention may be a method of treating a hydrocarbon with a hydrogen sulfide scavenger wherein the hydrogen sulfide scavenger includes a reaction product of glyoxal and a polyamine. The method may also include using a dispersant as a component of the hydrogen sulfide scavenger.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In one embodiment of the disclosure, a hydrogen sulfide scavenger may be a system of components including the reaction product of glyoxal and a polyamine. Glyoxal has the structure:
For the purposes of this application, the term polyamine shall mean a compound having 2 or more primary or secondary amine groups or at least one primary and one secondary amine group. These compounds shall include at least 2 carbons and may have as many as 12 carbons. In some embodiments, the polyamine may have from about 2 to about 10 carbons. In still other embodiments, the polyamine may have from about 2 to about 6 carbons.
The polyamines may be linear, branched, or cycloaliphatic. Exemplary polyamines useful with the method of the disclosure include ethylene diamine (EDA), diethylene triamine (DETA), triethylene tetramine (TETA), tetraethylene pentamine (TEPA), piperazine, cyclohexane diamine, butane diamine, and combinations thereof.
In one embodiment of the method of the disclosure, a reaction product of glyoxal and a polyamine is employed as a component of a hydrogen sulfide scavenger. The subject reaction product is a product prepared by a process including introducing the glyoxal with the polyamine under reaction conditions to induce an exothermic reaction. Any method known to be useful to those of ordinary skill in the art to be useful may be employed to produce the reaction product. For example, if not spontaneous, then the reaction may be catalyzed using an acid such as HCl.
The equivalent ratio of glyoxal to polyamine, in some embodiments of the method of the disclosure, may be from about 1:9 to about 9:1. In other embodiments the equivalent ratio of the glyoxal to the polyamine may be from about 1:7 to about 7:1. In still other embodiments, the equivalent ratio of the glyoxal to the polyamine may be from about 1:4 to about 2:1. In yet other embodiments, the equivalent ratio of the glyoxal to the polyamine may be about 1:1.
While not wishing to be bound under any theory, it is believed that the at least some of the glyoxal and polyamines react to form crosslinked copolymers having imine and di-imine moieties which interact with hydrogen sulfide to produce the scavenging effect observed with the claimed compositions and method.
In some embodiments of the method of the disclosure, the reaction product may not be as compatible as desired in a hydrocarbon being treated and thus a dispersant may be employed. The dispersant used may be cationic, anionic or non-ionic. Exemplary dispersants include, but are not limited to mono-ethylene glycol n-hexyl ether (Hexyl Cellosolve[R] available from Union Carbide); ethylene glycol monobutyl ether (Butyl Cellosolve[R]); di- and tri-propylene glycol derivatives of propyl and butyl alcohol, which are available from Arco Chemical (3801 West Chester Pike, Newtown Square, Pa. 19073) and Dow Chemical (1691 N. Swede Road, Midland, Mich.) under the trade names Arcosolv[R] and Dowanol[R]; mono-propylene glycol mono-propyl ether; di-propylene glycol mono-propyl ether; mono-propylene glycol mono-butyl ether, di-propylene glycol mono-propyl ether, di-propylene glycol mono-butyl ether; tri-propylene glycol mono-butyl ether; ethylene glycol mono-butyl ether; di-ethylene glycol mono-butyl ether, ethylene glycol mono-hexyl ether; di-ethylene glycol mono-hexyl ether; 3-methoxy-3-methyl-butanol; and mixtures thereof.
Polymeric dispersants may also be used. For example, ethoxylated long chain and/or branched alcohols, ethoxylated carboxylic acids, and ethoxylated nonylphenols having from about 2 to about 11 ethylene oxide (EO) units, ethoxylated long chain and branched alcohols, ethoxylated carboxylic acids, and ethoxylated esters of glycerol may be useful with some embodiments of the methods of the disclosure. Any dispersant that is useful for dispersing water soluble compounds into the hydrocarbon to be treated and that does not interact adversely with the surfactant and/or the hydrocarbon or any downstream processes that may be in the offing for the hydrocarbon, that is known to those of ordinary skill in the art, may be used.
In some embodiments of the claimed method, the hydrogen sulfide scavenger system may consist essentially of only the glyoxal and polyamine reaction product. For the purposes of this application, the terms “consisting essentially of” means that the hydrogen sulfide scavenger has no more than 5 percent by weight or, in some embodiments, no more than 1 percent by weight of any other nitrogen containing components. In still other embodiments, the hydrogen sulfide scavenger is prepared without a dispersant.
The hydrogens sulfide scavenger claimed herein are useful in treating hydrocarbons. The hydrocarbons may be crude, partially refined, or fully refined and pending commercial consumption. When the hydrocarbons to be treated are crude hydrocarbons, in one embodiment they may be very “crude” and be, for example, crude oil. In another embodiment, the crude hydrocarbon may only be “crude” in regard to a subsequent refining step. For example, in one embodiment, the method of the disclosure may be a refining step to produce light hydrocarbon fuels such as gasoline or aviation fuel. In refineries, the feed streams for such units have already undergone at least one step to remove components that are not desirable for producing such fuels. Thus, in this embodiment, the feed stream to this unit is a crude hydrocarbon even though it has had at least one refining process step already performed upon it.
In at least one embodiment of the method of the disclosure, the hydrocarbon being treated with a hydrogen sulfide scavenger is asphalt. For the purposes of this application, the term “asphalt” refers to any of a variety of materials that are solid or semisolid at room temperature and which gradually liquefy when heated, and in which the predominant constituents are naturally occurring bitumens (or kerogens) or which are bitumen like materials obtained as residue in petroleum refining.
The total feed rate of the hydrogen sulfide scavenger will generally be determined by the operator of the specific production process unit to be subjected to treatment using the claimed hydrogen sulfide scavengers. Those of ordinary skill in the art in operating such a unit will know how to make such determinations based upon the specific operating parameters of their production units. Nevertheless, in some embodiments, the feed rate of the hydrogen sulfide scavengers will be from about 10 to 10,000 ppm in the process stream being treated. In other embodiments, the feed rate will be from about 100 to 1,000 ppm. In still other embodiments, the feed range will be from about 200 to about 800 ppm. Often this rate is based upon a ratio of the scavenger to the hydrogens sulfide present. Such ratios are often based upon weight and can range, in some embodiments of the method of the disclosure, from (scavenger: hydrogen sulfide) about 1:200 to about 200:1.
The hydrogen sulfide scavengers of the application may be introduced into their target feed material in any way known to be useful to those of ordinary skill in the art subject to the caveat that the hydrogen sulfide scavengers are introduced prior to or concurrent with the a refining process. For example, in one application, the hydrogen sulfide scavenger is injected into the feed material upstream from a refining unit as the feed material passes through a turbulent section of piping. In another application, the hydrogen sulfide scavenger is admixed with the feed material in a holding vessel that is agitated. In still another application, the hydrogen sulfide scavenger is admixed with the feed immediately upstream of a refining unit by injecting the hydrogen sulfide scavenger into a turbulent flow, the turbulent flow being created by static mixers put into place for the purpose of admixing the hydrogen sulfide scavenger with a feed material. In still another embodiment, the hydrogen sulfide scavenger is atomized and fed into a vaporous feed stream using, for example, an injection quill.
When used outside of a refining process, the hydrogen sulfide scavengers may be introduced in any way useful for the target application. For example, when the application to be treated is an oil well, the scavenger may be introduced downhole or into the above ground equipment as are other, conventional scavengers. The claimed scavengers may also be introduced into pipelines, storage vessels and even into mobile storage vessels such as trucks, rail cars, and ship holds. Is some embodiments, scavengers are actively mixed and in others passively mixed with the hydrocarbons being treated.
EXAMPLES
The following examples are provided to illustrate the invention. The examples are not intended to limit the scope of the invention and they should not be so interpreted. Amounts are in weight parts or weight percentages unless otherwise indicated.
Example 1
Condensate, a liquid under ambient conditions which is a mixture of low molecular weight alkanes, is sparged with nitrogen having a hydrogen sulfide concentration of 1% for 1 hour.
The concentration of the hydrogen sulfide in the condensate prior to treatment (blank) is determined to be 19.9 ppm. The condensate is then tested by introducing a hydrogen sulfide scavenger prepared by reacting glyoxal and DETA at a molar ratio of 1:1 (which is an equivalent ratio of 1:2). The treated condensate and a blank were shaken using an orbital shaker at 400 rpm at ambient conditions for 4 hours. The blank was retested and had a hydrogens sulfide concentration of 10.5 ppm. The treated sample showed no measurable hydrogen sulfide (<0.5 ppm).
Example 2
Example 1 was repeated substantially identically except that the initial concentration of hydrogen sulfide was 30.8 ppm and the hydrogen sulfide scavenger was introduced at a concentration of 300 ppm. After treatment, the blank has a hydrogen sulfide concentration of 13.1 ppm. The treated sample showed no measurable hydrogen sulfide (<0.5 ppm).
Example 3
The hydrogen scavenger of Example 1 is used to immerse carbon steel corrosion coupons. The immersed coupons were held at about 40° C. for 14 days. The corrosion rate was determined to be about 19.19 mpy.
Discussion of Examples
The examples show that the claimed hydrogen sulfide scavengers are effective at reducing the concentration of hydrogen sulfide in hydrocarbons. They also show that the claimed hydrogen sulfide scavengers have a very low corrosion rate. | An effective hydrogen sulfide scavenger that produces little corrosion may be prepared by reacting glyoxal with a compound having at least two primary or secondary amine groups. The subject hydrogen sulfide scavengers may be used with both the production of crude oil and natural gas, and the refining of same. | 2 |
This application is a continuation, of copending application Ser. No. 718,176, filed on Aug. 27, 1976 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates generally to flexible tubes, and particularly to flexible tubes of the type having limited springback tendencies.
Flexible tubing made of rubber and cloth has been in existence for many years. Early attempts at improving their flexibility without an accompanying degradation in strength were directed at providing corrugations as exemplified by that disclosed in U.S. Pat. No. 314,440. Later, corrugations were formed in drinking tubes or straws to increase their flexibility as shown in U.S. Pat. No. 2,094,268.
Early tubular corrugations typically took a helical configuration. More recently, however, with the advent of thermoplastic materials, new configurations in corrugations have been made in an effort to simplify manufacture. For example, discontinuous grooves have been provided in flexible sections of thermoplastic drinking tubes as disclosed by U.S. Pat. No. 3,438,578. The material thickness in area of corrugations has also been varied to improve axial and radial flexibility as shown by U.S. Pat. No. 3,346,187.
Though the just described corrugated tubes have had good flexibility and strength, they have, by and large, been characterized by a high degree of resilience. Thus, once flexed or bent they have tended to reassume their originally constructed configuration unless held bent by ancillary holding means. In many situations, however, it is desirable to have the flexible tubing exhibit minimum springback tendencies once bent from its original configuration and thereby retain its bent configuration. Recently, new corrugations have been devised in efforts to overcome this problem of springback in drinking tubes as disclosed in U.S. Pat. Nos. 3,409,224, 3,445,552, and 3,908,704. The corrugations here are formed at skewed angles with the tube axes and with each corrugation defined by a groove having sides of unequal lengths. These unequal sides are joined together at the base of each groove at either a sharp angle therewith or with a close U-shape bend. The outside edges or ridges of corrugations have similar degrees of surface sharpness or roughness.
Though the just described flexible tubes have functioned relatively well, they have not been without disadvantages. For example, though a drinking tube or straw may incorporate only a relatively small flexible zone of the type described in an otherwise smooth tube, the ruffled outside edges of the corrugations have tended to impede their packaging into encapsulating paper covers. The straws are ordinarily sealed within paper jackets or covers by wrapping machines. The ruffled straw edges have caused excessively high rates of crinkling and jamming of the covers during machines wrapping operations to occur. In addition, to effect a bend of a given angle a predetermined number of grooves is required, which number has heretofore been rather large. The ruffled, peripheral surface of the flexible zone has also caused the drinking tubes or straws to become mutually interlocked rendering it difficult to process them during automatic packaging operations. Furthermore, when stored in hoppers these corrugations have also tended to reduce the degree of compactness with which large number of straws may be stored or processed.
Accordingly, it is a general object of the present invention to provide an improved flexible tube.
More specifically, it an object of the invention to provide an improved flexible tube of the type capable of retaining a bent configuration without appreciable springback tendency.
Another object of the invention is to provide a flexible tube of the type described having relatively smooth interior and exterior surfaces.
Another object of the invention is to provide a flexible tube of the type described requiring a relatively few number of circumferential grooves for effecting bends of selected angles.
Another object of the invention is to provide a flexible tube of the type described having minimal tendency to interlock with other tubes of the same configuration when stored in mutual abutment.
Yet another object of the invention is to provide a flexible tube of the type described capable of being stored in mass with an improved degree of compactness.
SUMMARY OF THE INVENTION
In one form of the invention a tube of thermoplastic material is provided having a flexible zone intermediate to the ends thereof which may be flexed without substantial springback. The flexible zone comprises a series of circumferential grooves with each groove having an annular floor from which two opposed groove sides convergently extend.
In another form of the invention a tube is provided having a flexible zone of low springback tendencies formed with a plurality of circumferential grooves having annular floors to which conical sides are joined at acute angles in forming toggle joints.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side elevational view of a flexible tube embodying principles of the present invention shown positioned in a bent configuration in an open-topped cup or vessel containing a liquid.
FIG. 2 is a side view, in cross-section, of the bent flexible zone of the tube shown in FIG. 1.
FIG. 3 is a cross-sectional view of the flexible zone of the tube shown in FIG. 1 in an early stage of tube fabrication.
FIG. 4 is a cross-sectional view of the flexible zone of the tube shown in FIG. 1 in a latter stage of tube fabrication.
FIG. 5 is a cross-sectional view of a flexible zone of a flexible tube illustrating one corrugation groove bent and one unbent.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in more detail to the drawing, there is shown in FIG. 1 a flexible, drinking tube or straw positioned within an open topped cup 10 in which a body of liquid 12 is contained. The drinking tube or straw is shown disposed within the cup with its lower end 14 positioned adjacent the inside bottom of the cup and with its upper end 15 located outside the cup where it is accessible to the lips and mouth of a person for drinking the fluid 12 from the cup through the straw. The tube is seen to be bent at a flexible zone or portion 16 intermediate two straight zones 34 and the tube ends 14 and 15 where it rests against and overhangs the annular cup lip 18. This flexible zone is shown in FIG. 4 to comprise a plurality of circumferential grooves of truncated-triangular cross-sectional configuration having annular, circular floors 20 from which two conical sides 22 convergently extend. Each of the two sides is of substantially the same size and configuration, being somewhat shorter axially than that of the annular floor. So formed, annular peripheral bands 24 linking adjacent grooves together have substantially the same outside diameter as that of the adjacent smooth sections 25 of the tube which straddle the flexible zone.
It will also be seen that the inner surfaces 26 of the groove floors 20 are annular and smooth and that the thickness of the material throughout the flexible zone is substantially uniform. The peripheral surfaces of the flexible zone are also relatively smooth and unruffled. As a result, tubes incorporating this flexible zone may be readily packaged into encapsulating paper or the like without jamming. Furthermore, they may be stored in hoppers in relatively compact configurations with minimal tendency to interlock with grooves of adjacent tubes.
Flexible tubes of the type embodying a flexible zone of the type just described may be made from numerous materials including various metals and plastics. When used as a drinking tube or straw as shown in FIG. 1, the material is preferably thermoplastic such as polypropylene of some 6 to 8 mils uniform thickness throughout the tube, including that of the flexible zone. The flexible zone itself may be formed by rolling the thermoplastic material onto a spindle and guide in a manner similar to that disclosed in U.S. Pat. No. 3,493,998, which patent is assigned to the assignee of the present application.
During formation the grooves are formed with walls 22 initially diverging from the groove floors 20 as shown in FIG. 3. Annular areas 27 of reduced thickness are also provided at the junctions of less than 180° of the groove sides with groove floors 20 and bands 24, which provide pivot points. Preferably, the wall thickness of these areas is between one half and three fourths that of the adjacent wall thickness. Thus, where the straw wall thickness is approximately 8 mils, the reduced thickness portions may be approximately 5 mils thick. Wall thinning is accomplished by providing staggered ridges on the confronting surfaces of the formation machinery spindle and die.
After the flexible zone has been so formed it is axially contracted. This action causes the side walls 22 to be forced with snap-like actions from their mutually divergent orientation of FIG. 3 to their mutually convergent orientation as shown in FIG. 4. This snap-like action results from the junctions of the groove sides with the floors and interconnecting bands functioning as toggle joints.
After the tube has been removed from the forming machines it may be flexed to a bent position and thereafter retain such configuration. During this operation individual groove walls on the outside of the bend snap, often in a random fashion, from mutually convergent to divergent configurations. In FIG. 5, for example, the outside wall portions of groove walls 40 have so snapped while their inside curved portion 41 have retained their mutually convergent orientation. Additional flexing of the tube causes groove walls 43 also to snap with toggle-like action to an open, mutually divergent configuration. In other cases, as shown in FIG. 2, the snap action of the groove walls along the convex side of the bent flexible zone is random. Here, for example, it is seen that groove walls 45 have snapped open while walls 46 have not. It thus is difficult to predict the exact order of the progression of toggle action.
We thus see that a flexible tube is provided of the type having minimal spring-back tendencies which has a substantially smooth and unruffled peripheral surface that may be easily packaged with minimal tendency to crinkle or jam the packaging material. The flexible tubes may be compactly stored with minimum chance for interlocking. They also may be easily formed from materials of substantially uniform thickness such as those of thermoplastic composition. A relatively few number of grooves is required to effect permanent bends of selected angles.
It should be understood that the just described embodiment merely illustrate principles of the invention in one preferred form. Many modifications, additions and deletions may, of course, be made thereto without departure from the spirit and scope of the invention as set forth in the following claims. | A tube of thermoplastic material having a flexible zone intermediate the ends thereof which may be flexed without substantial springback. The flexible zone comprises a series of circumferential grooves having an annular floor from which two opposed groove sides convergently extend. | 5 |
BACKGROUND OF INVENTION
1. Field of the Invention
The present invention relates to optical sorting machines for agricultural products.
2. Description of the Prior Art
U.S. Pat. No. 4,454,029, of which applicant is inventor, relates to a bichromatic sorter for agricultural products. These sorters have been primarily used to detect unacceptable agricultural products based on color of the product, such as coffee beans, peanuts and the like. There were certain types of relatively smaller, usually granular, agricultural products, such as rice grains which required only a monochromatic or gray level sort to reject unacceptable dark products. U.S. Pat. No. 3,738,484 related to a sorter for monochromatic sorting of this type. However, it was felt that the grains had to be maintained in serial flowing streams of spaced individual grains for accurate sorting. This placed an effective limit on the volume of grains which a sorter could process in a particular time interval. For increased productivity, additional sorters were required.
SUMMARY OF INVENTION
Briefly, the present invention provides a new and improved sorter for agricultural products, particularly small granular ones such as rice and the like. The products are sorted based on their illumination intensity as they fall in streams past an illuminated viewing chamber. The products are formed into a number of parallel, downwardly falling streams before passing into the viewing station. In these streams, there is no need to separate and scan each individual grain of product singly. Thus, sorter productivity is increased, while also increasing sort accuracy. A number of channels of optical scanning stations of like number to the number of falling streams of product are located in the viewing chamber. The streams of product are illuminated by fluorescent lamps in the viewing chamber and the amount of light reflected by the streams of falling product is sensed, usually monochromatically, and detected unacceptable products are ejected.
Each of the optical scanning stations takes the form of a plurality of aligned optical sensors to sense a subdivided portion of the area of the viewing chamber before the scanning station. The optical sensors form electrical signals indicative of the sensed light from the product, if any, present before it. The signals from the optical sensors for each individual channel are sequentially sampled or multiplexed and provided to an electronic processing circuit for comparison with a reference signal to determine if the products are acceptable. If not, they are ejected.
By subdividing the image area present before an optical viewing station channel into a number of areas, one for each optical sensor, and by sequentially scanning them in multiplex fashion, sorting rates and productivity are materially increased, while also affording an increase in sorting accuracy. Further, there is no need to separate the product into serial falling streams of spaced individual grains.
In addition to the fluorescent lamps which provide main illumination of the product, a background fluorescent lamp is provided to form a background illumination level for the viewing chamber. The sensitivity of the lamps is adjustable. Once set, it is automatically monitored and controlled. The intensity of the current driving each fluorescent lamp is also monitored and compared against its maximum rated value. If actual current through a lamp exceeds its rated value, an indication of this is provided.
The sorter of the present invention operates under control of timing circuitry which periodically turns off the fluorescent illuminating lamps and reverses the polarity of the voltage applied to them. During the same time interval that lamp polarity is reversed, the viewing chamber can be automatically subjected to a burst of air to clear any dust or particulate matter which may be present.
In a preferred embodiment, a sorter according to the present invention takes the form of two identical sorters, one located above the other. The lower sorter receives only the product ejected by the upper sorter as unacceptable, and retrieves a substantial percentage of acceptable product from the grain provided it.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a sorter according to the present invention.
FIG. 2 is an elevation view, taken partly in cross-section, of a product viewing station in the sorter of FIG. 1.
FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG. 2.
FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. 2.
FIGS. 5, 6 and 7.are elevation views of instrument panels in the sorter of FIG. 1.
FIG. 8 is a functional block diagram of the sorter of FIG. 1.
FIG. 9 is a schematic electrical circuit diagram for a single sorting channel in the sorter of FIG. 1.
FIG. 10 is a schematic electrical circuit diagram for an alternative single sorting channel for the sorter of FIG. 1.
FIGS. 11, 12, 13, 14, 15, 16, 17 and 18 are schematic electrical circuit diagrams of portions of the circuit of FIGS. 9 and 10.
FIGS. 19, 20, 21, 22 and 23 are waveforms illustrative of the operation of the circuitry of FIGS. 9 and 10, although not on a common time scale.
DESCRIPTION OF PREFERRED EMBODIMENT
In the drawings, the letter S (FIG. 1) designates generally a sorting machine according to the present invention for sorting small, granular agricultural products, such as rice grains and the like. The sorting machine S includes an upper sorter U and a lower sorter L mounted on a frame F. A power supply P (FIGS. 1 and 15) is provided on the frame F to produce operating electrical power and suitable bias voltages to the sorters U and L. The sorters U and L, other than their location on the framework F are of similar construction and operation. Accordingly, details of only one will be set forth, it being understood that the other is of similar structure and function.
The sorting machine S (FIG. 1) includes an upper hopper 10 into which the product to be sorted is deposited from a suitable source, such as conveyor system driven by an auger. The product passes from the upper hopper 10 into a lower transverse receiving chute portion 12. The product in the receiving chute 12 is spread out and falls onto a rearwardly slanting corrugated tray 14 which forms the grains of product into a number of parallel channels equal in number to the number of optical viewing channels in a viewing station V (FIGS. 2, 3 and 4). The corrugated tray 14 is moved by a vibratory motor 16 to assist in moving the product to be sorted rearwardly where it descends into a forwardly sloping feed tray 18.
The feed tray 18 is corrugated and has a like number of channels to the upper tray 14 and is mounted with an upper portion 20 of the frame F. In the lower sorter L, the breadth of the channels may be more narrow than in the upper sorter U to more closey singularize the flow of descending product into individual grains, if desired.
The product in each stream to be sorted descends from the corrugated tray 18 into a space 22 (FIG. 2) before a focusing lens 24 of an optical station O (FIG. 3), one of which is provided for each of the channels in the tray 18. The streams of product need not be single individual grains and may, for example, take the form of multiple grains simultaneously present before each focusing lens 24.
The focusing lens 24 (FIGS. 2 & 3) in each of the optical viewing stations O is a part of the sorting optics of the apparatus A which focuses light present in the space 22 onto a scanning photocell 28 through a narrow slot 30 formed in a masking disk 32. The scanning photocell 28 for each of the optical viewing stations O is in the form of a plurality of aligned photodiode cells 34 (FIG. 9). The scanning photocells 28 are mounted with a preamplifier board 36 (FIGS. 2 & 4) within a covered electronic chassis 38 (FIG. 1) in each of the upper sorter U and lower sorter L.
Control panels 40 (FIGS. 1 & 7) are mounted beneath the covered electronic chassis 38 in each of the sorters U and L. The illumination level in the space 22 in the viewing station V is provided by a pair of illuminating fluorescent lamps 42 (FIGS. 2, 8 & 18). A background illumination fluorescent lamp 44 (FIG. 2) provides a reference or background illumination signal onto a reflective plate 46 which provides an indication of illumination conditions onto the lens 24. The background illumination is set at a suitable level to distinguish between unacceptable and acceptable product being sorted. In the event that the product passing through the space 22 is darker than the reference or background level set by lamp 44 for a particular stream of product passing before an optical station O, an ejector solenoid 48 is activated (FIG. 8), producing a jet or blast of air from an ejector J (FIG. 2) which forces the unacceptable product into a discard chute or hopper 50. Acceptable product passes through the viewing station V into a transport chute or member 52 from which it is fed through a funnel 54 (FIG. 1) into a bag or other suitable container.
The discard chute 50 of the upper sorter U transports the rejected product into the feeder chute 14 for the lower sorter L. It should be noted that the unacceptable product stream from the upper sorter U may include otherwise acceptable grains, since the product passes in streams rather than in singularized individual grains into lower sorter L where a similar sorting operation again takes place.
The funnel or feed member 54 may, as is shown in the drawings, be deleted from the lower sorter U and replaced with a conveyor system so that the unacceptable, rejected product from lower sorter L may be discarded or furnished again, along with incoming product to be sorted into the upper hopper 10.
The sorter S of the present invention includes as electrical circuitry an electronic processing circuit E (FIG. 8) for each channel of product being sorted in the viewing station V, as well as a lamp control circuit K in the power supply P for the sorters U and L. The electronic processing circuit E for each viewing channel includes sorting optics (FIGS. 2 and 3) for each of the optic stations O which sense the light conditions present in the viewing station V adjacent thereto and furnish electrical signals representative of sensed light conditions to a preamplifier circuit 56 (FIG. 8). The sensitivity for each channel of the preamplifier circuit 56 is controlled by a pre-amplifier gain control circuit 58 (FIGS. 9 and 10).
The preamplifier circuit 56 furnishes electrical signals indicative of the optical conditions sensed before the particular associated optical station O in the viewing station V to an amplifier circuit 60 (FIGS. 9, 10 and 11) in the circuit E for that channel. A channel sensitivity circuit 59 is provided for each channel to adjust the sensitivity of that particular channel. The amplified signals from the amplifier circuit 60 are provided to a classification circuit 62 (FIG. 8) where a determination is made as to whether the stream of product passing through the viewing station V in individual channels is acceptable or unacceptable depending upon the degree of darkness of the product.
The classification circuit 62 in one version of circuit E further provides periodic adjustments to the amplifier circuit 60, as will be set forth. In the event that an indication of unacceptable product is formed in the classification circuit 62, a delay circuit 64 allows a suitable interval of time to elapse for the unacceptable product to pass from the optical station O to a position in front of the ejector J, at which an ejector predrive circuit 66 and an ejector drive circuit 68 are caused to energize the ejector solenoid 48, passing a blast of air into the stream of product and diverting the unacceptable stream of product into the chute or funnel 50.
In the lamp control circuit K, the lamps 70 (FIGS. 8 and 18) receive operation power through a power supply circuit 72 (FIGS. 8 and 14). An illumination sensitivity circuit 74 (FIGS. 8 and 16) and a lamp control circuit 76 (FIGS. 8 and 16) adjusts the illumination intensity of the lamps 70. A timing control circuit 78 (FIGS. 8 and 17) periodically reverses the polarity of the direct current driving bias for the lamps 70 through a lamp start circuit 80 (FIGS. 8 and 18). The timing control circuit 78 further periodically activates a chamber clearing solenoid 82 in the viewing station V, to blow dust and accumulated particulate matter from the viewing station V which might otherwise interfere with the accuracy of sorting operations. The timing control circuit 78 further controls the operation of the feeder 16 during the time intervals of operation of the lamp start circuit 80 and chamber clearing solenoid 82.
Turning now to the details of the electronic processing circuit E (FIG. 9), the aligned photocells 34 in a particular one of the optical stations O are provided in a suitable number so that their aligned span equals the width of area focused on them by lens 24. The photocells 34 are electrically connected through an associated preamplifier 84 in preamplifier circuit 56 to a gain reference potentiometer 86 and low pass filter 88. In an alternating current (AC) coupled version of the electronic processing circuit E (FIG. 9), a coupling capacitor 90 is connected between the potentiometer 86 and the low pass filter 88. In a direct current (DC) coupled version of the electronic processing circuit E (FIG. 10), no coupling capacitor is present. Other than the absence of the capacitor 90 and the presence of a periodic automatic gain control function performed by classification circuit 62 on amplifier circuit 60 in the direct current coupled version, both the alternating current and direct current coupled versions of the electronic circuitry E are identical in structure and function to each other.
The low pass filter 88 for each of the aligned optical sensors 34 in a particular optical station O are electrically connected to an analog multiplexer 90 which, under address commands furnished thereto over conductors 92, 94 and 96 from the classification circuit 62 (FIG. 13) selectively and sequentially samples the electrical signals from the pre-amplifiers 84.
The signals are thus sequentially passed under control of the multiplexer 90 to an amplifier 98 (FIG. 9) which also receives an offset bias signal over a conductor 100 from a potentiometer 102. The signal from the amplifier 98 is provided as one input to a comparator amplifier 104 which receives at its other input a sensitivity level signal over a conductor 106 from the channel sensitivity circuit 50 (FIG. 11). The comparator 104 senses whether or not the darkness of the image presented to the sensing photodiodes 34 exceeds a preestablished sensitivity level for that particular channel. In the event that an unsatisfactorily dark image is present, the comparator 104 provides a classifier trip output signal 105 (FIG. 19) of suitable duration, such as about 25 microseconds, through an OR gate 108 (FIG. 9) to energize a monostable multivibrator or ONE-SHOT 110, forming an ejector pulse 111 (FIG. 19) of from one-half to two milliseconds.
The ejector pulse 111 passes from the multivibrator 110 (FIG. 9) into a shift register 112 which is driven by clock pulses 113 (FIG. 19) from an oscillator circuit 114 (FIG. 9). The frequency of clock pulses 113 from the oscillator circuit 114 controls the speed and movement of the ejector pulse 111 from the multivibrator 110 through the shift register 112 so that the unsatisfactory or abnormal dark grain of product being sorted is present before the ejector jet J at the time the ejector solenoid 48 is energized. The ejector pulse 111 formed in the multivibrator 110 after a time passage through the shift register 112 of from four to eight milliseconds energizes a transistor 116 with a pulse 117 (FIG. 19), passing a signal through the ejector predriver circuit 66 and ejector driver circuit 68 to activate the ejector solenoid 48.
The multivibrator 110 for each sorting channel may also be periodically activated by an ejector test signal for that particular channel over a conductor 118 from gating circuitry in the classification circuit 62 (Fig. 13). A bypass conductor 120 (FIG. 9) is connected at the output of the comparator amplifier 104 to permit a signal to be provided directly to the shift register 112 from the comparator 104 so that an unduly long time interval of a detected unacceptable condition, usually longer than the duration of ejector pulse 111 does not pass undetected. This permits long duration dark spots to be detected and not be overlooked during the reset time of the multivibrator 110.
An inhibit transistor 122 (FIGS. 9 and 10) is connected to the conductor 120 to ground or inhibit passage of signals from the comparator amplifier 104 during switching of the multiplexer 90 to the next successive optical sensor during the first half of each time slot for the channel. The transistor 122 is energized over a conductor 124 from the classification circuit 62 (FIG. 13). The gate 108 is also electrically connected by a conductor 126 to an ejector test on-off switch 128 (FIGS. 7 and 9) which is located on a control panel 130 (FIGS. 1 and 7).
The sensitivity control signals for each of the viewing channels 0 are formed in its channel sensitivity circuit 59 (FIG. 11), as exemplified by the one on the conductors 106, are established by means of a potentiometer 132 for that channel and connected through an amplifier 134 to an overall or common sensitivity control potentiometer 136. The adjustment of the potentiometer 136 is controlled by a knob 137 (FIG. 7) on the panel 130. The individual channel sensitivity signals are furnished over conductors, such as a conductor 106 to the comparator amplifier 104 for that particular channel (FIG. 13).
For the direct current coupled version of electronic processing circuit E (FIG. 10), amplifier 138 (FIG. 11) establishes a gain reference signal over a conductor 142 which is provided to an integrating comparator amplifier 144 (FIG. 10) in a gain control feedback network 146. The output of the amplifier 144 (FIG. 10) is provided to a light emitting diode of gain control network 146 (FIGS. 10 and 11) to control the resistance of a photosensitive resistor in network 146. This resistance, as controlled, is connected to an input to amplifier 98 to periodically adjust the gain of amplifier 98.
A classifying signal 147 (FIG. 22) is formed for each channel of the viewing stations V in its comparator amplifier 104 and is furnished over a conductor 148 to the gate 108 (FIGS. 9 & 12). In the event of an unacceptable product or products in the chamber in front of the viewing station V, ejector pulse 111 is formed to drive the ejector solenoid 48 in the manner set forth above. In the delay circuit 64 (FIG. 12), a transistor 150 is electrically connected in common to the inhibit input of the multivibrators 110 for each channel. The transistor 150 and a resistor 152 and capacitor 154 associated therewith establish a brief time delay upon initiating the ejector test function during which the multivibrators 110 are inhibited, preventing ejector pulses 111 from being formed during this transient situation.
The classification circuit 62 (FIG. 13) includes a time slot control circuit 160 which furnishes the scan control signals over conductors 92, 94 and 96 to the multiplexer 90 (FIGS. 9-11) to sequentially scan the aligned optical sensors in a particular viewing channel or optical station O. In the time slot control circuit 160, (FIG. 13) a master voltage controlled oscillator 161 providing master frequency signals 162 (FIG. 22) at a frequency of about eighty kilohertz is coupled through a logic level converting transistor 163 to a four bit binary counter 164. The transistor 163 provides compatibility between logic levels of oscillator 161 and counter 164 when the latter components have different logic levels. The binary counter 164 provides four bit counting signals indicated in FIG. 22 to drive a decoding buffer circuit 165 to cause multiplexer 90 to individually select the aligned optical sensors 34 via conductors 92, 94 and 96 in a sequence. The scanning rate of the multiplexer 90 is about twenty kilohertz.
An inverter gate 166 reverses the logic level of the bit one count from counter 165 to inhibit by means of an inhibit pulse waveform 167 over conductor 124, sensing of optical conditions during the first half-cycle for each of the photodiodes 34. This disables the gate 108 and multivibrator 110 during the first half-cycle of each scanning cycle. In this manner, spikes or transients 168 (FIG. 22) formed during each switching operation of the multiplexer 90 are inhibited from being detected as undesirable dark spots in the product being sorted.
In the direct current-coupled embodiment of the present invention, one of the photodiodes 34, typically the last in the row, is located in each viewing station O at a position away from the descending stream of product to sense background illumination levels for gain control purposes. A gate 169 is connected to appropriate bits, such as the third and fourth ones, from counter 164 to form, after inversion in gate 170, an inhibit pulse 171 for the duration of a background sensing interval once during each photodiode scanning cycle. It is during this background sensing interval that background illumination conditions in the viewing station V before the particular photocell 28 are monitored. This inhibit pulse from gate 170 passes through buffer 165 during the background sense interval over conductor 124 (FIGS. 9, 10, 12 and 13) to the delay circuit 64 to inhibit classification or sorting during background sensing. This inhibit function occurs in a like manner to the lamp reversal inhibit function when polarity of the illuminating lamps 42 is being reversed, as will be set forth.
Another classify inhibit function is performed by diode 174 over a conductor 176 when the ejector test switch 128 (FIGS. 7 and 12) has been activated. Activation of the ejector test switch 128 further provides operating power over a conductor 178 (FIG. 13) to a frequency control oscillator 180 in an ejector channel selector circuit 182 in the classification circuit 62. The oscillator 180 establishes the rate at which the ejectors E in each of the individual channels are pulsed. The frequency of the oscillator 180 is controlled by a potentiometer 184 which is adjusted by an ejector frequency control knob 196 (FIG. 7) on the panel 130. When the ejector for a particular channel is being selected and tested by the counting circuit 182, an indicator light emitting diode 185 (FIG. 7) on the panel 130 is also energized, indicating that such testing is being performed. The indicator light emitting diodes 185 also indicate ejector operation during normal sorting operations.
The channel test counter circuit 182 (FIG. 13) is driven by an oscillator 188 which drives a four bit digital counter circuit 190 through a set of UP/DOWN control gates 192. The gates 192 are activated by an UP/DOWN control switch 194 (FIG. 7) on the front panel 130 and control whether the count of pulses stored in the counter 190 (FIG. 13) is to be increased or decreased on each pulse from the oscillator 188. The oscillator 188 is activated under control of a change test channel button 196 on the panel 130. The count stored in the counter 190 of the test channel counter circuit 182 is provided to decode circuits 198 and 200 which in connection with a set of parallel NOR gates 202 decode and indicate the particular ejector solenoid 48 to be tested.
For the direct current coupled version (FIG. 10) of the sorter S, an analog switch 203 (FIGS. 10 and 13) is provided to receive a gain adjust activate signal 204 (FIG. 22) over a conductor 205 (FIGS. 10 and 13). The analog switch 203 is activated by signal 204 during the last two scanning cycles of the counting circuit 160 as detected by a gate 206 at the output of gate 170 and furnished through buffer 165. In this manner, viewing conditions sensed by that particular channel are passed through the electronic processing circuit E to the reference amplifier 144 and photosensitive resistor 146 to adjust the input attentuator of amplifier 98 to compensate for background conditions in the optical station O. During this time, a signal is furnished over conductor 124 (FIGS. 9, 10, 12 and 13) to inhibit ejector operations.
In the ejector predrive circuit 66 (FIG. 14), an input signal from the delay circuit 64 is received, causing a transistor 206 to conduct. An integrating amplifier 208 connected to the collector of the transistor 206 begins accumulating a charge at this time, building up a voltage which is furnished to a comparator amplifier 210. The output of the comparator 210 is connected to the collector of a transistor 212. During normal sorting operations, pulses from the delay circuit 64 are passed through the transistors 206 and 212, as indicated at 214 (FIG. 20), giving rise to short duration pulses which energize power transistors 216 and 218, permitting operating voltage to pass through a current limiting resistor 220 to a coil 222 of ejector solenoid 48 driving the ejector J. When this occurs, the indicator light-emitting diode 185 on the panel 130 (FIG. 7) for that channel is energized, indicating that its ejector 48 is receiving current.
There are at times instances when a relatively long trip signal, on the order of several seconds, as indicated at 226 (FIG. 20) renders the transistor 206 conductive. At the beginning of the time interval 226, the output of integrator 208 (FIG. 14) begins to increase, as indicated by a waveform 228. At a point in time, indicated at 230, the output of the integrator 208 exceeds the bias level provided to the comparator 210 by a bias establishing network 232, causing the comparator 210 to reverse states, or clamp, as indicated at 233. For the remainder of the long duration trip signal waveform 226, the output of comparator 210 remains at a level inhibiting the flow of current through the power transistors 216 and 218, inhibiting the flow of excess current through the solenoid 222 of the ejector 48, preventing damage to the solenoid 222. At a point 234 of termination of the trip signal 226, the voltage at the output of integrator 208 begins to decrease, as indicated at 236, until a point 238 is reached where input to the comparator 210 is unclamped.
In the lamp power control circuit 72 (FIG. 15), operating power is provided over input lines 240 and 242 to an electronics control on-off switch 244. When the switch 244 is closed, alternating current on the lines 240 and 242 is passed through a transformer 246 to suitable direct current power supply circuit 248. A cooling fan 250 and lamp filament transformers 256 (FIG. 18) at this time also receive operating power from the lines 240 and 242. A lamp ON/OFF switch 252 mounted on a control panel 254 (FIG. 5) controls the application of electrical power from the lines 240 and 242 to a lamp power supply transformer 257 (FIG. 15) which through a controlled rectifier network 258 provides direct current voltage over a line 260 (FIGS. 15 and 18) to the lamp circuit 70, providing operating power for the lamps 42.
A solid state relay 262 (FIG. 15) of circuit 72 is electrically connected to the lines 240 and 242. On closure of the lamp switch 252, relay 262 permits current to flow through an ejector ON/OFF switch 264 mounted on the control panel 254 (FIG. 5) so that the alternating current voltage on the lines 240 and 242 (FIG. 15) may pass to a transformer 266 and a rectifier circuit 268, providing an operating power bias over a conductor 270 to the ejector drive circuit 68 (FIG. 14). A transformer 272 also receives alternating current voltage when the switch 264 is closed, and through a rectifier network 274 provides direct current operating power to the feeder power control 275 which under control of timing control circuit 78 applies power to the feeders 16 for both the upper sorter U and lower sorter L. Electrical power is also provided to drive solenoids 276 and 278 as commanded by timing control 78. The solenoids 276 and 278 if used in a manner to be set forth below, periodically provide a purging blast of air through the viewing stations V of the sorters U and L in order to clear any dust and extraneous matter which may have accumulated in the viewing stations during operation of the sorter S.
In the illumination sensitivity circuit 74 (FIG. 16), a background illumination sensing photodiode 280 is located in the vicinity of the background illumination lamp 44 (FIG. 2) and provides a signal indicative of the sensed optical conditions through a converting amplifier 282 (FIG. 16) to a first input of a differential amplifier 284. The differential amplifier 284 receives at its other input a background illumination sensitivity level set by a potentiometer 286 which is furnished thereto through a buffer amplifier 288. The setting of the potentiometer 286 is controlled by a control knob 290 (FIG. 5) on the control panel 254.
The illumination sensitivity circuit 74 (FIG. 16) further includes sensing photodiodes 292 located near each of the main illumination lamps 42 for both of the sorter stations in the sorter S. The photodiodes 292 form electrical signals indicative of the illumination conditions sensed. These signals are furnished through buffer amplifier 294 and are provided to differential amplifiers 296. The differential amplifiers 296 further receive at their other inputs a reference level signal furnished through buffer amplifiers 298 by a sensitivity setting potentiometer 300. The setting of the potentiometer 300 is controlled by a sensitivity adjustment knob 302 (FIG. 5) on the control panel 254.
The differential amplifiers 284 and 296 form signals whose voltage is indicative of the difference between the desired illumination level in the viewing stations, as indicated by the potentiometers 286 and 300, and the actual illumination conditions, as sensed by the photodiodes 280 and 292. The differential signals formed in the amplifiers 284 and 296 are furnished to operational amplifiers 304 which function as voltage to current converters. The output current from the operational amplifiers 304 thus represents the differential between desired and actual illumination intensity conditions in the viewing station V. This differential controls the amount of current which flows through power transistors 312 (FIG. 18) connected to the output of operational amplifiers 304. Each of the power transistors 312 is connected by a conductor 314 through a polarity reversal switch 316 to one of the lamps 42 in the lamp control circuit 70 (FIG. 18). The transistors 312 permit current to pass through the lamps 42 at a controlled level thereby controlling the intensity of the illumination provided by the lamp 42.
The conductor 310 provides the negative input to amplifier 304 (FIG. 16) with a voltage established by the current through a resistor 317 (FIG. 18) at the emitter of power transistor 312 which indicates the amount of current through the associated lamp 42. The voltage on conductor 310 thus represents the current through the associated lamp and is connected through a coupling resistor 318 of lamp control circuit to a first input of a comparator amplifier 320 to provide an indication of the magnitude of the current flowing through the lamp 42. The other input of the comparator amplifier 320 is provided with a reference level formed by a resistor network 322 indicative of the maximum rated current for the lamp 42. As long as the current level flowing through the conductor 310 to lamp 42 does not exceed the rated current for the lamp 42 as indicated by the resistor network 322, the comparator amplifier energizes an indicator light emitting diode 324a of an encapsulated indicator pair 324 on control panel 254 indicating that rated current for the lamp has not been exceeded. In the event that the comparator 320 senses that rated current through lamp 42 has been exceeded, comparator 320 changes state and energizes as an alternative indicator light emitting diode 324b of pair 324. Light emitting diode 324a is preferably one that emits green light while a light emitting diode 324b is preferably one that emits red. It should be understood, however, that different colors of light may be equally as well used.
The conductor 310 is also connected through a resistor 328 to a comparator operational amplifier 330. The amplifiers 330 also function as current sensors and hold a common output conductor or bus 332 at a low level until all of the lamps 42 are sensed to be conducting at least some minimum current. The conductor 332 is connected to a transistor 334 which is not conductive so long as the conductor 332 is at a low level, indicating that not all of the lamps 42 are conducting current. With the transistor 334 non-conductive, an oscillator 336 provides pulsed current signals to a transistor 338 as indicated by a waveform 340 (FIG. 21) which are provided in common to the primary side 344 (FIG. 18) of a transformer 346 in the lamp start circuit 80. The primary side 344 of the transformer 346 forms a voltage waveform 348 (FIG. 22) with a positive transient or spike due to its inductive reactance. The wave form 348 in the primary side 344 of transformer 346 induces a large negative going pulse 350 (FIG. 21) in a secondary coil 352 of the transformer 346, which is furnished to the lamp 42 until the lamp 42 becomes conductive.
Once all of the comparator operational amplifiers 330 (FIG. 16) sense that the lamp associated therewith is conducting current, the voltage on conductor 332 transits to a high level, rendering transistor 334 conductive and inhibiting oscillator 336 from forming further pulses.
One blade of the lamp ON/OFF switch 252 (FIGS. 5, 15 and 16) is also electrically connected to the inhibit input terminal of the oscillator 336 (FIG. 16) so that when the switch 252 is moved to the OFF position (FIG. 16), oscillator 336 is inhibited from forming lamp start pulses. When this blade of the switch 252 is moved to the ON position, the solid state relay 262 (FIG. 15) is energized over the conductor 352.
The inhibit input terminal of the oscillator 336 is also electrically connected to an oscillator inhibit transistor 354 (FIG. 16) whose operation is controlled by a lamp current inhibit transistor 356. The lamp current inhibit transistor 356 is electrically connected to the base of each of the transistors 306. When the transistor 356 is energized, the collectors of the transistors 306 are grounded, inhibiting the flow of current through the power transistors 312 and lamps 42. The transistor 356 turns on the transistor 306 and inhibits oscillator 336 through transistor 354 on receipt of a lamp shutdown signal over a conductor 358 from the timing circuit 78 or by opening of the switch 244 (FIGS. 15 and 16). A damping capacitor 359 slowly discharges current through closed switch 244 to prevent rapid change of polarity of the lamps 42.
The electrical conductor 332 is connected through two inverter stages 360 and 362 by a conductor 364 to the lamp timing circuit 78 (FIG. 17) to indicate to the timing circuit 78, by the voltage level present on conductor 364, whether or not all of the lamps 42 as sensed by capacitor amplifiers 330, are conducting current. A transistor 366 is rendered conductive when voltage conditions on conductor 364 indicate that all lamps are receiving current, permitting current to pass through a relay coil 368, moving a contact 370 to a position to provide an electrical ground for indicator light-emitting diodes 324 and 326 so that they can emit light.
In the timing control circuit 78 (FIG. 17), a main delay monostable multivibrator or one-shot 372 forms an output pulse 374 (FIG. 23) after a time interval governed by a time control circuit 376. The main delay time interval is typically on the order of fifteen or twenty minutes, and represents the approximate time interval after which it becomes necessary to reverse the polarity of the current flowing through the lamp reversal contacts 316 (FIG. 18) to the lamps 42. The pulse 374 formed in main delay monostable 372 (FIG. 17) is furnished as an input signal to a further monostable multivibrator 378 which forms a feeder shutdown pulse waveform 380 (FIG. 23) on a conductor 382 and a lamp reverse pulse 384 on a conductor 386. A lamp reverse monostable multivibrator 388 (FIG. 17) forms a lamp reverse pulse 390 (FIG. 23) in response to the pulse 384 which is furnished to a bistable switch or toggle 392. Toggle 392 then changes states, as indicated by the waveform 394. The waveform 394 when transiting to a high level renders a transistor pair 396 conductive, allowing current to flow through a lamp reverse relay coil 398, causing the contacts 316 (FIG. 18) controlling the direction of current through the lamp 42 to change position. When the toggle 392 again transits to a low logic level, the transistor pair 396 is rendered nonconductive, interrupting the flow of current through the lamp reverse relay 398 and again causing the contacts 316 to change position. The pulse 384 formed in monostable 378 is also furnished as a input to a lamp shutdown monostable multivibrator 400, causing the monostable 400 to form a lamp shutdown pulse 402 over a conductor 404 and an opposite logic level pulse 406 which is furnished over the conductor 358 to the lamp current inhibit transistor 356 (FIG. 16), interrupting the flow of current through the lamps 42.
The lamp shutdown pulse 406 on the conductor 404 is furnished as an input to a NAND gate 407. The gate 407 also receives as an input the voltage condition on conductor 364 indicative of the conductive status of the lamp 42. As indicated by a waveform 408 (FIG. 23), after a short delay to allow all of the lamps 42 to become conductive after the change of state of the lamp shutdown pulse 402, the voltage level present on the conductor 364 provided to the Gate 407 transits to a high level. The waveform 408 on the conductor 364 is further provided as an input over a conductor 410 to a background blowdown monostable multivibrator or one-shot 412. Multivibrator 412 provides a pulse 414 (FIG. 23) over a conductor 416 to the gate 407 and a pulse 418 over a conductor 420 to a transistor 422. Transistor 422 on receipt of the pulse 418 renders transistors 424 and 426 conductive for the duration of the pulse 418 to power control board 275, permitting current to flow through the background blowdown solenoids 276 and 278 (FIG. 15), permitting bursts of air to be blown through the viewing stations V to cleanse them of any dust or other particles which may have accumulated.
NAND gate 407 is connected through an inverter gate 428, a low pass filter 430 and an inverter 432 to form an ejector cancel pulse 434 (FIG. 23) which causes a transistor 436 to become conductive, inhibiting the OR gate 108 in the delay circuit 64 (FIG. 12) for the duration of the ejector cancel pulse 434.
An inverted version of the pulse 434 (FIG. 23) is provided from the inverter 428 as an input to an NAND gate 438 (FIG. 17) which receives as its second input pulse 384 on conductor 382. The gate 438 forms a feeder cancel pulse 440 (FIG. 23) which after inversion in inverters 442 and 444 (FIG. 17) is furnished in parallel to NOR gates 446. The feeder cancel pulse 440 passes from gates 446 through inverter 448 to a pair of feeder cancel transistors 450. Transistors 450 over conductors 452 inhibit operation of the feeders 16 for the sorters U and L for the duration of the feeder cancel pulse 440. Each of feeder cancel transistors 450 is also connected through one of gates 446 to an inverter 454 to a feeder control switch 458 located on a feeder control panel 460 (FIG. 6) so that the operator may disable both the upper and lower feeders 16.
An inverter 460 (FIG. 17), a low pass filter 462 and another inverter 464 are electrically connected to the inverter 442 so that the feeder cancel pulse 440 from the gate 438 is provided in inverted form as a main delay monoreset pulse 466 (FIG. 23) over a conductor 468 (FIG. 17) as an input to main delay monostable 372. Pulse 466 resets monostable 372 on completion of the lamp reversal and, where used, chamber clearing functions performed under control of the timing control circuit 78.
A lamp reverse override switch 470 (FIGS. 5 and 17) is provided on the front panel 254. When depressed, the override switch 470 (FIG. 17) causes a monostable multivibrator 472 to form a pulse, causing the main delay monostable 372 to change states at a time earlier than its normal time of change of state. When this occurs, the chamber clearing and lamp reversal functions take place in response to the operator depressing switch 470 in the same manner as if the normal time delay of monostable 372 had expired.
In the operation of the present invention, the product to be sorted is fed into the hopper 10 and are formed into a number of parallel downwardly falling streams in the trays 14 and 18 before passing into the viewing station V. As has been set forth, these streams may have a number of individual grains adjacent each other and there is no need that they be separated into individual singly vertically spaced grains of product before being passed into the viewing station V.
In the viewing station V, the aligned photodiode cells in each of the optic viewing stations O sense a subdivided portion of the area of the viewing chamber V before the station O. The optical sensor photocells 34 form electrical signals indicative of the sensed light of the product, if any present before them. The signals from the optical sensor photocells 34 are sequentially electrically sampled or multiplexed by the multiplexer 90 for comparison with a reference signal in the comparator amplifier 104 of the classification circuit 62 to determine if the products are acceptable. If they are not, an output pulse 105 (FIG. 19) is formed, causing the monostable 110 to form a pulse 111 which passes through the delay circuit 64, emerging as a pulse 117 which is furnished to the ejector predrive circuit 66 and ejector drive circuit 68 to activate the solenoid 48, furnishing a burst of air through the ejector jet J in the viewing station V, blowing the unacceptable product into the chute 50 in the upper sorter U, from which it passes into feeder trays 14 and 18 of the lower sorter L where a similar sorting operation takes place. The acceptable product from the lower sorter L is fed from trays or chutes 52 into a suitable container. The unacceptable product from the lower sorter L is either discarded or furnished along with new, incoming grain into the chute or hopper 10 of the upper sorter U for further sorting.
During sorting operations, the intensity of the current flowing through the lamps 42 is continually monitored to determine if the rated current for each particular lamp is ever exceeded. If the rated current for one of the lamps 42 is exceeded, the alarm light emitting diode of diode pair 324 associated therewith is activated to indicate that rated current has been exceeded. The particular lamp 42 in question may then be replaced. In addition, during sorting operations, the illumination intensity output of each of the lamps 42 is compared against a reference level. In the event that the illumination level of a particular lamp varies from the reference level, the amount of current being furnished to the particular lamp 42 is adjusted to bring the illumination intensity output of the particular lamp 42 back to the reference level.
After a period of time set by main delay monostable 372, the feeder shut down pulse 384 and lamp shut down pulse 406 are formed and the polarity of current supplied to the fluorescent lamps 42 is reversed. Oscillator 336 is activated and furnishes pulses to pulse transformer circuits 346 for each of the lamps 42, furnishing such pulses until all of the lamps 42 are illuminated. At this point, sorting operations resume.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, components, circuit elements, wiring connections and contacts, as well as in the details of the illustrated circuitry and construction may be made without departing from the spirit of the invention. | A sorter is provided for sorting unacceptable agricultural products from acceptable ones. The sorter is preferably a monochromatic one performed as the products pass in streams past an illuminated viewing station. The view station includes a plurality of optical stations, each composed of a plurality of aligned optical sensors. The optical sensors sense the reflected light from the stream of product passing the optical station and form electrical signals indicative of the sensed light. The electrical signals from the sensors in individual optical stations are sequentially sampled or multiplexed at a rate which permits the product to pass through the viewing station at an increased volume, rather than in serial fashion, increasing the productivity of the sorting operation. Unacceptable products are ejected as they are sensed. The ejected product stream is subjected to a second sort to increase sort accuracy. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
Co-Pending Patent Application
[0001] Methods for Detection of Ultraviolet Light Reactive Alternative Cellular Energy Pigments (ACE-pigments) William John Martin Submitted Dec. 24, 2007. Publication number 20090163831
[0002] Method of assessing and of activating the alternative cellular energy (ACE) pathway in the Therapy of Diseases. William John Martin Submitted Jan. 16, 2008.
[0003] Publication number 20090181467
[0004] Enerceutical mediated activation of the alternative cellular energy (ACE) pathway in the therapy of diseases. Submitted May 8, 2008. Publication number 20090280193
[0005] Enerceutical activation of the alternative cellular energy (ACE) pathway in therapy of diseases. Submitted Feb. 11, 2009. Publication number 20090202442
[0006] Method of using the body's alternative cellular energy pigments (ACE-pigments) in the therapy of diseases Submitted Feb. 20, 2009. Publication number 20100215763
[0007] Urine as a source of alternative cellular energy pigments (ACE-pigments) in the assessment and therapy of diseases. Submitted Mar. 5, 2009. Publication number 20100196297
[0008] Diagnostic value of systemic ACE pathway activation in the detection by fluorescence of localized pathological lesions. Submitted Jul. 26, 2010. Publication number 20100291000
[0009] Enerceutical mediated activation of the alternative cellular energy (ACE) pathway in the therapy of diseases. Submitted July 2010.
[0010] Energy Charged Liquids to Enhance Enerceutical Activation of the Alternative Cellular Energy (ACE) Pathway in the Therapy of Diseases. Submitted Dec. 17, 2010.
[0000] Application Ser. No. 12/972,344
[0011] Energy Charged Alcoholic Beverages for Enhancing the Alternative Cellular Energy Pathway in the Prevention and Therapy of Diseases. Submitted January 2011.
Application Number
[0012] Methods for Detecting and Monitoring the Activity of Energized Water and Other Liquids Useful for Enhancing the Alternative Cellular Energy Pathway in the Prevention and Therapy of Diseases. Submitted February 2011
[0013] Methods for Increasing the Kinetic Activity of Alcohol, Water and Other Liquids, so as to Render the Liquids More Useful in Enhancing the Alternative Cellular Energy Pathway in the Prevention and Therapy of Diseases. Submitted February 2011
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0014] Not applicable: No Federal funding was received in support of this patent application.
REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0015] Not applicable.
BACKGROUND OF THE INVENTION
[0016] In recently submitted co-pending patent applications, which are incorporated by reference herein, I disclosed that the passage of electrolytically derived Water Gas (otherwise known as Brown's Gas) into alcohol (200 proof absolute ethanol) greatly enhances the ability of the alcohol to react with neutral red dye and with alternative cellular energy (ACE) pigments (defined in the co-pending patent applications). When a small number (usually around 10) of neutral red dye particles (obtained directly from a commercially available neutral red dye powder e.g. Dudley Corp. N.J.), are gently sprinkled onto a plastic dish, which contains Water Gas “charged” alcohol, there is rapid and vigorous dissolving of most of the material within the neutral red dyes particles. This occurs in a directional manner forming long, narrow red streams of dissolved neutral red. Equally impressive, fine particles, breaking away from the larger particles of neutral red dye, which remain non-dissolved in the alcohol solution, undergo continuing to-and-fro movements, with apparent attractive forces rapidly alternating with repulsive forces. The linearity of the dissolving neutral red and the dynamic movements of non-dissolved particles occur in regular (non-charged) absolute alcohol, but are greatly heightened by Water Gas charging of the alcohol. The use of charged alcohol also significantly enhances the intensity of the orange fluorescence of the neutral red solution, when compared with dye dissolved in non-charged alcohol. As the alcohol (both charged and non-charged) finally evaporates, the precipitating neutral red dye assumes attractive, banded circular patterns, as if being influenced by an interactive energy field. The patterns are more striking using charged alcohol. The charged alcohol also shows greater interaction than does non-charged alcohol with ACE pigments collected from the saliva and/or perspiration of virus infected patients. When used therapeutically, as described in co-pending patent applications, the combination of neutral red with charged alcohol is decidedly more effective in enhancing the ACE pathway in energy deficient individuals, when compared with, still quite impressive, benefits obtained using untreated (non-charged) alcohol.
[0017] The linear dissolving pattern of neutral red dye observed in alcohol solutions, was also observed in various alcoholic beverages, especially when they were charged with Water Gas. This extraordinary pattern is not ordinarily seen when neutral red dye is added to ordinary (non-charged) water in similar plastic dishes. Instead, slowly dissolving neutral red particles become gradually surrounded by the dissolved dye in essentially concentric discs of red dye. An exception is seen with some plastic drinking glasses and some plastic covered paper cups. In these containers, there is an obvious attraction between the plastic material and the neutral red particles, leading to radial movements of the particles towards the interface between the surface of the water and the plastic container. (These types of containers are, therefore, unsuitable for used in the experiments described in this application). I have commonly used small (1.5″) square individual polycarbonate dishes and various multi-well tissue culture dishes. The dishes are generally observed using a low power, dissecting microscope with spacing between the light and the dish to help reduce heat transfer. In some experiments light emitting diode (LED) illumination was used to exclude heat, as opposed to light, as the cause of particle movements.
[0018] An important finding was observed when neutral red dye particles, are gently sprinkled (scattered) onto a plastic dish of distilled water, and the dish is placed in close proximity to a dish of charged alcohol with moving neutral red dye particles. Instead of the particles in the water remaining essentially stationary and only slowly dissolving, several of the particles will begin to move throughout the water. Moreover, if additional neutral red dye is added, the fresh particles will show more linear dissolving patterns with movements of the remaining non-dissolved particles. The energy transference effect is best seen when the dishes are in direct contact or comprise adjacent wells within the same multi-well dish. Physical contact is not absolutely necessary, however, and the effect has been seen between separated dishes. I, thereby, discovered that the altered dissolving pattern of neutral red dye in ordinary water potentially provided a simple assay for detecting a radiating energy coming from the well containing the charged alcohol and neutral red particles. The assay also provides a means of detecting the water and alcohol energizing capacities of various additional forms of energy, in addition to that provided by Water Gas. For convenience, this assay will be subsequently referred to as the “NR-Kinetic Assay.”
[0019] Specifically, the present patent application extends on the finding that a charged alcohol containing solution of neutral red, provides a very efficient method of transferring a dynamic activity, expressed using the NR-Kinetic Assay, and other measures, as explained herein, to water and other liquids. Charging of the alcohol solution is generally achieved using a combination of votexing followed by bubbling of water gas. Further optimization, as assessed by the NR-Kinetic Assay, can potentially be achieved using sound energy of approximately 500 Hz, electromagnetic, magnetic and electrostatic energies, and by the addition of magnesium chloride. Of special interest is that the indirectly activated water and other liquids have now been shown to be able to transfer quite striking NR-Kinetic Assay activity to added additional liquids, including water.
[0020] The charged alcohol plus dissolved neutral red dye method was primarily developed to activate the ACE pathway in humans and animals. The newer findings provide additional approaches to this goal, such as drinking and bathing in dynamically activated water, and using such water in the cultivation of edible foods. Various industrial applications of dynamically activated water can also be inferred from other studies and are also becoming apparent from ongoing research.
BRIEF SUMMARY OF THE INVENTION
[0021] The NR-Kinetic assay was used to demonstrate easily discernable increased dynamic activity in water and alcoholic beverages in which a container of alcohol and NR dye, is partially submerged and illuminated with a UV light. The water and alcoholic beverage retain the enhanced dynamic activity after removal of the container and can be used to further activate other fluids, by either addition to the liquid or by being placed in close proximity to the liquid. The level of activation of water in which the container of alcohol and neutral red dye is placed, is enhanced by prior charging of the alcohol by magnetic vortexing and bubbling of Water Gas before adding neutral red dye. The indirectly activated water not only shows markedly heightened activity in the NR-Kinetic Assay, but the resulting solution can fluoresce with UV illumination. Moreover, the NR containing, indirectly activated water, can be used to create NR-Kinetic Activity in other liquids placed in close proximity. Indirectly activated water, without neutral red, has been consumed and used for bathing, including
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Not Applicable and none included
DETAILED DESCRIPTION OF THE INVENTION
[0023] The NR-Kinetic Assay has previously been employed in the direct assessment of various kinds of processed liquids, including absolute alcohol and alcoholic beverages. For instance, it was also used to demonstrate the marked effect of simply bubbling Water Gas through absolute alcohol on the ability of the “charged” alcohol to react with neutral red dye. Not only was there more of a direct effect on neutral red added to the Water Gas charged alcohol, such as more intense fluorescence, but the light illuminated charged alcohol solution containing neutral red dye, was clearly able to distantly induce movements of non-dissolved neutral red dye particles placed in an adjacent well containing regular water. In this assay, the light illuminated neutral red dye containing charged alcohol was placed in one of the wells of a tissue culture plate. Adjacent wells contained water plus stationary un-dissolved neutral red dye particles. These wells were observed microscopically to see whether any of the non-dissolved neutral red particles would begin to move, which they did beginning approximately 30-60 seconds later. An additional observation on the adjacent neutral red dye in water wells included the occasional formation of numerous gas bubbles, which might well represent the formation of Water Gas. The energy transference type of assay consistently provided positive results, which were not seen using multiple wells in other culture dishes, which simply had water plus neutral red solutions.
[0024] These studies prompted interest in whether the indirectly activated water may have beneficial properties, beyond those of ordinary water. Additionally, studies were undertaken to compare the indirectly activated water with waters with claimed therapeutic benefits, including the well water from Bheau View Ranch in San Marcos Calif., water through which Water Gas had been bubbled and water exposed to variously processed volcanic rock-derived materials. The later were chosen because of my reasoning that the reasons for certain aquifers may be providing more “energized” waters is exposure to forces present within materials in the earth's crust. Some of these materials can be delivered to the earth's surface via volcanic eruptions. Moreover, these types of materials have been used in a wide range of animal husbandry, agricultural and industrial applications with apparent benefit.
[0025] Water from the well at the Bheau View Ranch, San Marcos, Calif. was tested using the NR-Kinetic Assay and shown to have discernable activity. A Ziploc bag containing 30 ml of absolute alcohol (ethanol, Sigma Aldrich), which had been vortexed for 3 minutes using a magnetic stirrer (Jura-Capresso Inc. model 202, Milk frother) followed by bubbling of a mixture of hydrogen, oxygen, air and Water Gas (generated from a Brown' Gas Electrolyzer, advertized on www.watertogas.com, as a way of enhancing automobile fuel economy). The 1 pint (essentially 500 ml) closed jar uses six overlapping washers, alternatively linked to the anode and the cathode of a 4.5 volt power supply, delivering 500 m Amps. Water containing approximately 10 gm of either citric acid or sodium bicarbonate, as the electrolyte, is added to the jar, prior to connecting the electrodes. A small aquarium air pump at 2.2 Watt (Whisper) is used to transfer the evolving hydrogen, oxygen and Water Gar from the jar into the alcohol solution using plastic tubing. Bubbling of the gas is allowed to proceed for 30 minutes, allowing for some evaporation of alcohol, but with sufficient left to proceed with the experiment. Thirty ml (essentially 1 oz) of the charged alcohol are added to a Ziploc bag with the further addition of approximately 15 mg of neutral red powder. The Ziploc bag is further sealed using heat and is then available for various uses, including the activation of other liquids. (The same solution preparation procedure is commonly used, with UV illumination, to activate the ACE pathway in individuals by either taping the Ziploc bag onto the sole of a foot (as practiced by the mother of an adolescent child with autism), placed into the open mouth of adults with systemic deficiencies in their ACE pathway, or placed onto sites of previously occurring recurrent herpes simplex virus (HSV) induced skin lesions. The UV light is generally provided via a 13 Watt Halco spiral lamp or if unavailable a UV fluorescent tube, using UV protective goggles.)
[0026] For water activation, the Ziploc bag is inserted into a partially filled glass containing the water and exposed from above to the UV light. The fluid within the Ziploc bag shows a bright orange fluorescence. At varying times, a small aliquot of the water from the glass is examined microscopically using the NR-Kinetic Assay. This type of study showed the rapid and intense activation of the water, which actually showed fluorescence with the dissolving and dynamically moving neutral red. Using this approach, marked enhancements of the dynamic activity of the Bheau View Ranch water, regular tap water, various bottled waters and to these waters which were further exposed to bubbled Water Gas using the watertogas apparatus (www.watertogas.com) and/or to volcanic rock-derived materials, including Stirwands (www.stirwandsdirect.com) and so called Kiko Stones (www.kikotechnology.com).
[0027] The striking positive dynamic activity enhancing results obtained by placing UV illuminated charged alcohol with neutral red dye solution, into water, was confirmed using other beverages, including alcoholic drinks, fruits and vegetable juices, milk and soft drinks While issues such as increased viscosity of some of the liquids and decreased solubility of neutral red dye limited the usefulness of the NR-Kinetic Assay, the sense was gained of each drink acquiring dynamic energy from the UV illuminated neutral red dye in alcohol solution.
[0028] Ongoing studies are based on determining if drinking the energized liquids can provide clinical benefits beyond that of drinking comparable amounts of the same liquids in their non-energized form. Assistance with such studies has been requested from the mother of a child with autism and from other individuals. Preliminary findings are encouraging. For example, the mother of the autistic child has used the procedure to charge both water and V8 vegetable juice. She definitely discerned clearer pronunciation and more complete sentence formation by her daughter. The mother is extending the study by noting changes in intra-oral UV fluorescence of her child as a result of the energized drinks Similar studies are ongoing in another ACE pathway deficient individual now regularly drinking energized beverages.
[0029] Other potential therapeutic applications under consideration are using energized water in footbaths, regular bath water, spas, cosmetic formulations, humidifiers, etc. The results, to date, argue that neutral red or other suitable dye, with appropriate illumination, leads to a better distant transmission of the activating energy, without the need for contiguous liquid. In other words, a footbath of energized water has not yet proven to be effective, as compared to using the UV illumination of neutral red containing alcohol in a Ziploc bag that is attached to the sole of the patient's foot. Drinking of indirectly energized liquids, has, however, produced clinical benefits in a human and would presumably also do so in animals.
[0030] Over the last several years, I have been well aware of the potential animal husbandry and agricultural applications of various water treating devices and additives. A major goal of animal husbandry is to enhance growth rate and minimize illness in farmed animals, including cows, pigs, sheep and fish. For edible crops, the emphasis is on growth rate, along with taste and shelf life. Cut flowers are mainly judged on their color and how long they survive. Farmers have been introduced to approaches of improving their water. The methods include i) applying a vortex spin to water; ii) passing water through electric, magnetic and electromagnetic fields; sound energy; iii) addition of volcanic and heated ceramic stones, etc. There are reasonably consistent reports that these various approaches can be at least, somewhat advantageous when applied to farming.
[0031] Energized water is also reported as having benefits in various industrial applications, including inhibiting and even reversing rust corrosion in metal pipes in cooling towers, boilers, etc. Energized water is also said to have improved cleansing properties, requiring less soap.
[0032] At least, based on the NR-Kinetic Assay results, the UV illuminated charged alcohol with neutral red dye method is likely to be superior to these alternative approaches in these various agricultural and industrial applications. Moreover, as previous shown and confirmed using the new format, it is possible to utilize sunlight as the source of UV light in the energy transfer from a charged alcohol:neutral red solution to either a patient or a glass of water.
[0033] The intriguing finding of a beneficial effect of treated liquids extending to larger volumes of liquids to which it is directed added or diluted by also does not require the use of a UV light. The mechanism by which the smaller volume of liquid can affect a larger volume of water is consistent with a resonance effect, not unlike the ability of a ringing tuning fork to stimulate the ringing of other tuning forks of the same frequency.
[0034] The principles, preferred embodiments and modes of operation of the present invention, intended to be protected herein, is not to be construed as limited to the use of only treated alcohols, since regular alcohol (ethanol) can also be used, although somewhat less effectively. Similarly, the present patent application is not restricted to the use of neutral red as the primary receiver of the UV, or even regular light energy. Other dyes are currently under evaluation, including acridine orange and methyl violet. Neutral red has the advantage, however, of having been used in therapeutic endeavors, aimed at activating the body's ACE pathway. The term “energized” is also not meant to be exclusive of other relevant terms, which I or other investigators may use in furthering the research described in this application. An operational alternative term being used is E3 water, which stands for etheric energy expanded water.
[0035] Additional modifications of the basic tenets disclosed in the present patent application will readily occur to those skilled in the art and especially upon practicing the currently described methods. For example, kits can be devised, which comprise a battery driven UV light and a sealed compartment for the alcohol plus added neutral red dye. The light can be turned on and the kit submerged into a water pond for growing rice, or a swimming pool, etc. A UV illuminated, liquid containing device can be attached to piping that is not necessarily transparent to the fluorescent component. The kits can also comprise previously activated water or other liquids, which can be subsequently diluted into a larger volume of liquid. The quantitative volume and time limitations of such approaches can be monitored using the NR-Kinetic Assay. | A method for energizing water and other liquids is described. It is based on previous studies showing the use of ultraviolet (UV) light illuminated of alcohol containing neutral red dye as a means of activating the alternative cellular energy (ACE) pathway. Rather than directly activating the patient, the method's ACE pathway, it is used to activate water and liquids for drinking by the patients. Once activated, a liquid can further activate a larger volume of liquid by simply being added to the larger volume of liquid. The methods should find widespread application in human, animal, agricultural and industrial uses of water and other liquids. | 8 |
FIELD OF THE INVENTION
The invention relates to catalysts useful for polymerizing olefins. In particular, the invention relates to catalysts that contain at least one anionic ligand derived from a thiopyran dioxide.
BACKGROUND OF THE INVENTION
Interest in single-site (metallocene and non-metallocene) catalysts continues to grow rapidly in the polyolefin industry. These catalysts are more reactive than Ziegler-Natta catalysts, and they produce polymers with improved physical properties. The improved properties include narrow molecular weight distribution, reduced low molecular weight extractables, enhanced incorporation of α-olefin comonomers, lower polymer density, controlled content and distribution of long-chain branching, and modified melt rheology and relaxation characteristics.
Traditional metallocenes commonly include one or more cyclopentadienyl groups, but many other ligands have been used. Putting substituents on the cyclopentadienyl ring, for example, changes the geometry and electronic character of the active site. Thus, a catalyst structure can be fine-tuned to give polymers with desirable properties. Other known single-site catalysts replace cyclopentadienyl groups with one or more heteroatomic ring ligands such as boraaryl (see, e.g., U.S. Pat. No. 5,554,775), pyrrolyl, indolyl, (U.S. Pat. No. 5,539,124), or azaborolinyl groups (U.S. Pat. No. 5,902,866).
Isolobal equivalents to the cyclopentadienide anion (i.e., other types of cyclic, anionic, 6π-electron donor ligands) provide an opportunity to expand the capabilities of single-site catalysts. There is a continuing need for catalysts with higher activities and/or the ability to produce polyolefins with better physical properties or improved processability. Of particular interest are catalysts that can be made from readily available starting materials.
SUMMARY OF THE INVENTION
The invention is catalyst system useful for polymerizing olefins. The catalyst system comprises an organometallic complex and an optional activator. The complex includes a Group 3 to 10 transition, lanthanide, or actinide metal and at least one anionic thiopyran dioxide ligand. Because a wide variety of thiopyran dioxides are easy to prepare from commercially available starting materials, the invention enables the preparation of a new family of single-site catalysts.
DETAILED DESCRIPTION OF THE INVENTION
Catalyst systems of the invention comprise an organometallic complex and an optional activator. The complex is “single site” in nature, i.e., it is a distinct chemical species rather than a mixture of different species. Single-site catalysts, which include metallocenes, typically give polyolefins with characteristically narrow molecular weight distributions (Mw/Mn<3) and good, uniform comonomer incorporation.
The organometallic complex includes a Group 3 to 10 transition, lanthanide, or actinide metal, M. More preferred complexes include a Group 4 to 10 transition metal. Group 4 complexes are particularly preferred.
The complex includes at least one anionic thiopyran dioxide ligand. These ligands are prepared by deprotonating a thiopyran dioxide using a potent base.
The simplest thiopyran dioxide is 2H-thiopyran-1,1-dioxide, which has the structure:
Deprotonation removes a methylene proton and generates an anionic species that is an isolobal equivalent of the cyclopentadienide anion:
The anion is incorporated into an organometallic complex as described later below.
Suitable thiopyran dioxides can include subsituent groups such as alkyl, aryl, alkoxy, aryloxy, halide, dialkylamino, nitro, or the like, provided that one methylene proton (on the sp 3 -hybridized carbon next to the SO 2 group) is present. The thiopyran dioxide can be prepared by any suitable method. In one preferred method, the procedure of Y. Gaoni ( J. Org. Chem. 46 (1981) 4502) is used. This method makes the thiopyran dioxide in three steps from a 3-sulfolene, which is available commercially or from the reaction of a diene (e.g., butadiene or isoprene) with sulfur dioxide. The route provides access to a wide variety of substituted thiopyran dioxides because substituted dienes are readily converted to the corresponding 3-sulfolenes.
In the three-step method, a 3-sulfolene is first reacted with dichlorocarbene. The resulting adduct is partially dehalogenated with lithium aluminum hydride. Base-catalyzed ring expansion with lithium diisopropylamide gives the desired thiopyran dioxide (Scheme 1):
Other suitable methods for making thiopyran dioxides have been described. See, for example, E. Molenaar and J. Strating, Rec. Trav. Chim. Pays-Bas 86 (1967) 1047 or J. Kuthan, “Pyrans, Thiopyrans, and Selenopyrans,” in Adv. Heterocycl. Chem. 34 (1983) 145 and J. Kuthan et al., “Developments in the Chemistry of Thiopyrans, Selenopyrans, and Teluropyrans,” in Adv. Heterocycl. Chem. 59 (1994) 179, and references cited therein.
In addition to an anionic thiopyran dioxide ligand, the organometallic complex may include additional labile or polymerization-stable, anionic ligands. Polymerization-stable ligands include, for example, substituted and unsubstituted cyclopentadienyl, fluorenyl, and indenyl, or the like, such as those described in U.S. Pat. Nos. 4,791,180 and 4,752,597, the teachings of which are incorporated herein by reference. Suitable polymerization-stable ligands include heteroatomic ligands such as boraaryl, pyrrolyl, indolyl, quinolinoxy, pyridinoxy, and azaborolinyl as described in U.S. Pat. Nos. 5,554,775, 5,539,124, 5,637,660, and 5,902,866, the teachings of which are incorporated herein by reference. Suitable polymerization-stable ligands include indenoindolyl anions such as those described in PCT publication WO 99/24446 and copending appl. Ser. No. 09/417,510, filed Oct. 14, 1999, now U.S. Pat. No. 6,232,260. The organometallic complex usually includes one or more labile ligands such as halides, alkyls, alkaryls, aryls, dialkylaminos, or the like. Particularly preferred are halides, alkyls, and alkaryls (e.g., chloride, methyl, benzyl). A variety of other kinds of ligands are particularly useful with late transition metals, including, for example, N,N′-diaryl-substituted diazabutanes and other imines as described in U.S. Pat. Nos. 5,714,556 and 5,866,663, the teachings of which are incorporated herein by reference.
The catalyst system optionally includes an activator. Activators help to ionize the organometallic complex and activate the catalyst. Suitable activators are well known in the art. Examples include alumoxanes (methyl alumoxane (MAO), PMAO, ethyl alumoxane, diisobutyl alumoxane), alkylaluminum compounds (triethylaluminum, diethyl aluminum chloride, trimethylaluminum, triisobutyl aluminum), and the like. Suitable activators include acid salts that contain non-nucleophilic anions. These compounds generally consist of bulky ligands attached to boron or aluminum. Examples include lithium tetrakis(pentafluorophenyl)borate, lithium tetrakis(pentafluorophenyl)aluminate, anilinium tetrakis(pentafluorophenyl)borate, and the like. Suitable activators also include organoboranes, which include boron and one or more alkyl, aryl, or aralkyl groups. Suitable activators include substituted and unsubstituted trialkyl and triarylboranes such as tris(pentafluorophenyl)borane, triphenylborane, tri-n-octylborane, and the like. These and other suitable boron-containing activators are described in U.S. Pat. Nos. 5,153,157, 5,198,401, and 5,241,025, the teachings of which are incorporated herein by reference.
The optimum amount of activator needed relative to the amount of organometallic complex depends on many factors, including the nature of the complex and activator, whether a supported catalyst is used, the desired reaction rate, the kind of polyolefin product, the reaction conditions, and other factors. Generally, however, when the activator is an alumoxane or an alkyl aluminum compound, the amount used will be within the range of about 0.01 to about 5000 moles, preferably from about 0.1 to about 500 moles, of aluminum per mole of transition, lanthanide, or actinide metal, M. When the activator is an organoborane or an ionic borate or aluminate, the amount used will be within the range of about 0.01 to about 5000 moles, preferably from about 0.1 to about 500 moles, of activator per mole of M.
The activator is normally added to the reaction mixture at the start of the polymerization. However, when a supported catalyst system is used, the activator can be deposited onto the support along with the organometallic complex.
The organometallic complex is prepared according to methods that are well known in the art. In general, the complexes are made by combining an anionic thiopyran dioxide ligand with a transition metal source.
The thiopyran dioxide anion is produced by deprotonating a thiopyran dioxide with a potent base. Usually, about one equivalent of base is used, but an excess may be used. Suitable bases include alkali metals (e.g., sodium or potassium), alkali metal hydrides (sodium hydride, lithium hydride), alkali metal aluminum hydrides (lithium aluminum hydride), alkali metal alkyls (n-butyllithium, methyllithium), Grignard reagents (methyl magnesium bromide, phenyl magnesium chloride), and the like. The deprotonation step is normally performed at or below room temperature by combining the thiopyran dioxide and the deprotonating agent, usually in the presence of one or more dry organic solvents, especially ethers and/or hydrocarbons.
Any convenient source of transition metal can be used. For example, the complexes can be made from transition metal halides, alkyls, alkoxides, acetates, amides, or the like. A particularly convenient source of the transition metal is the transition metal halide. For example, one can use titanium tetrachloride, zirconium tetrachloride, cyclopentadienylzirconium trichloride, tetrakis(dimethylamino)zirconium, vanadium(III) chloride-tetrahydrofuran complex (VCl 3 (THF) 3 ), titanium(III)chloride THF complex, chromium(III)chloride-THF complex, cobalt(II) chloride, nickel(II) bromide, platinum(II) chloride, palladium(II)chloride, lanthanum(III) chloride, titanium(III)acetate, or the like. Complexes can also be prepared from salts with labile groups, such as tetrakis(acetonitrile)palladium(II) bis(tetrafluoroborate).
The transition metal complexes are easy to make. Usually, the transition metal source (halide, e.g.) is dissolved or suspended in an organic solvent and the anionic thiopyran dioxide ligand is carefully added. Refluxing is used if needed to complete the reaction. Insoluble by-products, if any, can be removed by filtration, solvents are evaporated, and the transition metal complex is isolated, washed, and dried. The resulting complex can generally be used without further purification.
The organometallic complexes of the invention are expected to be valuable catalysts, catalyst precursors, or reagents for a variety of organic reactions, including, for example, olefin metathesis, isomerization, oligomerization, and polymerization reactions.
The invention includes catalyst systems that have enhanced ability, when compared with conventional metallocenes (e.g., bis(cyclopentadienyl)zirconium dichloride or bis(indenyl)zirconium dichloride), for incorporating α-olefin or cyclic comonomers in an olefin polymerization process. These catalyst systems comprise an organometallic complex and an optional activator (as described above). The complex includes a Group 3 to 10 transition, lanthanide, or actinide metal, M, and an anionic, heterocyclic ligand that is π-bonded to M. Preferably, M is a Group 4 transition metal. The heterocyclic ligand has a heteroatom, X, that is bonded to an out-of-plane Lewis base donor atom, A. The Lewis base donor atom can coordinate with M. Suitable heteroatoms (X) include oxygen, sulfur, boron, nitrogen, and phosphorus. Suitable Lewis base donor atoms include oxygen, nitrogen, sulfur, and phosphorus.
In one preferred catalyst system, the complex has the substructure (i.e., partial structure):
in which M is a Group 4 transition metal, A is oxygen, and X is sulfur, nitrogen, or phosphorus. More preferably, the heterocyclic ligand is an anionic thiopyran dioxide, and the complex has the substructure:
in which M is a Group 4 transition metal.
The catalyst systems are optionally used with an inorganic solid or organic polymer support. Suitable supports include silica, alumina, silica-aluminas, magnesia, titania, clays, zeolites, or the like. The supports can be pretreated thermally or chemically to improve catalyst productivity or product properties. The catalysts can be deposited on the support in any desired manner. For instance, the catalyst can be dissolved in a solvent, combined with a support, and stripped. Alternatively, an incipient-wetness technique can be used. Moreover, the support can simply be introduced into the reactor separately from the catalyst. The anionic thiopyran dioxide ligand can also be chemically tethered to the support through a suitable linking group.
The invention includes an olefin polymerization process. The process comprises polymerizing an olefin in the presence of a catalyst system of the invention according to methods that are well known in the art. Olefins useful in the process of the invention are compounds having at least one polymerizable carbon-carbon double bond. Preferred olefins have a single carbon-carbon double bond. They include ethylene and C 3 -C 20 α-olefins such as propylene, 1-butene, 1-hexene, 1-octene, and the like. Isoolefins (e.g., isobutene or isooctene) or cycloolefins (e.g., cyclohexene) are suitable as are cyclic olefins (e.g., norbornene) and dienes (e.g., 1,3-butadiene). Some or all of the olefin can be replaced with an acetylenically unsaturated monomer (e.g., 1-octyne or 1-hexyne). Mixtures of olefins can be used. Ethylene and mixtures of ethylene with C 3 -C 10 α-olefins are especially preferred.
Functionalized comomoners can be included provided that the comonomer also contains at least one polymerizable carbon-carbon double bond. Such functionalized monomers are used advantageously with late transition metal catalysts. For example, the olefin polymerization can be conducted in the presence of a minor proportion of allyl alcohol, acrylic acid, hydroxyethylmethacrylate, or the like. Olefin polymers prepared by the process of the invention have recurring olefin units.
Alternating copolymers of ethylene or other α-olefins, diolefins, or cyclic olefins with carbon monoxide or sulfur dioxide are also accessible using catalysts of this invention. Catalysts of the later transition metals (iron, cobalt, and nickel triads) are particularly useful for copolymerizing these monomers.
The polymerization is advantageously performed in the presence of an ionic liquid. Copending U.S. appl. Ser. No. 09/557,429, filed Apr. 25, 2000, now abandoned, the teachings of which are incorporated herein by reference, explains how to use ionic liquids with single-site catalyzed olefin polymerizations. Suitable ionic liquids are salts that exist in the liquid state at temperatures used to polymerize olefins. Preferred ionic liquids are liquids at and below room temperature, and many are liquids at temperatures as low as about −100° C. Preferably, the ionic liquids consist of a bulky organic cation and a non-coordinating, complex inorganic anion. The anion is “non-interfering” with respect to the single-site catalyst, i.e., it does not prevent or significantly inhibit the catalyst from effecting polymerization of the olefin. A wide variety of ionic liquids suitable for use in the process of the invention have been described. For example, U.S. Pat. Nos. 5,827,602, 5,731,101, 5,304,615, and 5,892,124, the teachings of which are incorporated herein by reference, disclose many suitable ionic liquids.
Many types of olefin polymerization processes can be used. Preferably, the process is practiced in the liquid phase, which can include slurry, solution, suspension, or bulk processes, or a combination of these. High-pressure fluid phase or gas phase techniques can also be used. The process of the invention is particularly valuable for solution and slurry processes. Suitable methods for polymerizing olefins using the catalysts of the invention are described, for example, in U.S. Pat. Nos. 5,902,866, 5,637,659, and 5,539,124, the teachings of which are incorporated herein by reference.
The following examples merely illustrate the invention. Those skilled in the art will recognize many variations that are within the spirit of the invention and scope of the claims.
EXAMPLE 1
Preparation of a Single-Site Catalyst
5-Methyl-2H-thiopyran-1,1-dioxide is prepared in three steps from 3-methyl-3-sulfolene using the method of Gaoni, J. Org. Chem., 46 (1981) 4502. Thus, 3-methyl-3-sulfolene is first reacted with chloroform and aqueous sodium hydroxide in the presence of a quaternary ammonium salt to give the dichlorocarbene adduct. Partial dehalogenation with lithium aluminum hydride in tetrahydrofuran gives the chlorocyclopropane. Finally, base-catalyzed ring expansion with lithium diisopropylamide gives the desired thiopyran dioxide compound (see Scheme 1, above).
5-Methyl-2H-thiopyran-1,1-dioxide (288 mg, 2.0 mmol) in diethyl ether (25 mL) is deprotonated by careful addition of n-butyllithium (1.3 mL of 1.6 M solution in hexanes, 2.1 mmol) at −78° C. The resulting anion is separated from excess salts by filtration in vacuo.
The anionic thiopyran dioxide solution is added by cannula to a stirred slurry of cyclopentadienyl zirconium trichloride (526 mg, 2.0 mmol) in diethyl ether (25 mL) at −78° C. The reaction mixture is stirred and allowed to warm to room temperature. Volatiles are removed in vacuo. The residue is extracted with toluene to give a solution of the organometallic complex. This solution can be used “as is” for polymerizing olefins. The expected product has the structure:
EXAMPLE 2
Polyethylene Preparation
Methyl alumoxane (5 mL of 10 wt. % MAO in toluene) is added to a portion of the product from Example 1 (200 mg). The mixture is injected into a 1.7 L stainless-steel autoclave containing dry, deoxygenated isobutane (850 mL) and triisobutylaluminum (0.2 mmol). The autoclave is heated to 80° C. and is pressurized with ethylene (150 psi). After 1 h, the autoclave is cooled, isobutane is flashed off, and polyethylene, the expected product, is isolated.
Molecular Modeling Study
In a preliminary, low-level molecular modeling study, single-site catalysts that incorporate anionic thiopyran dioxide ligands were compared with some common bridged and non-bridged metallocenes. The relative stabilities of model active sites were calculated, and the abilities of these sites to incorporate comonomers were estimated.
Active-site geometries were optimized using the semi-empirical method PM3tm (Titan software, distributed by Wavefunction, Inc. and Schrodinger, Inc.). To predict the relative stabilities of the active sites, enthalpies were calculated for the hypothetical abstraction of a methyl anion:
Tendency for comonomer incorporation was then estimated from the relative energies of forming pi-complexes of these cationic active sites with ethylene or propylene. The more exothermic the energy of pi-complexation of propylene vs. ethylene, the greater the predicted tendency to incorporate comonomers:
The results of the study indicate that the oxygen atoms of the thiopyran dioxide ligand are involved in two strong, specific interactions: The axial or “inside” oxygen coordinates to the transition metal and helps to stabilize the cationic active site. The equatorial or “ousted” oxygen interacts with Lewis acid centers in the activator.
Relative active site stabilities are estimated as follows:
The results suggest that catalysts from organometallic complexes that incorporate anionic thiopyran dioxide ligands will be somewhat less active than conventional metallocene complexes.
Interestingly, however, the model also predict that the thiopyran dioxide-based catalysts will be excellent for incorporating comonomers. Relative ability to incorporate comonomers:
In sum, preliminary calculations indicate a more stable active site and correspondingly reduced activity for the subject single-site catalysts compared with bridged or non-bridged metallocenes, but the model also predicts an enhanced tendency of the subject catalysts to incorporate comonomers.
The preceding examples are meant only as illustrations. The following claims define the invention. | Single-site catalysts useful for polymerizing olefins are disclosed. The catalysts incorporate a Group 3 to 10 transition, lanthanide, or actinide metal and an anionic thiopyran dioxide ligand. Because a wide variety of thiopyran dioxides are easy to prepare from commercially available starting materials, the invention enables the preparation of a new family of single-site catalysts. | 8 |
BACKGROUND OF THE INVENTION
[0001] The invention herein generally relates to the field of imaging systems for use in the graphic arts industry. Further, the invention more specifically relates to reducing perceivable artifacts from being formed in printed images.
[0002] Color images are often printed using four colors (more or less colors are also known), yellow, cyan, magenta, and black. For each color used on a printing press, a different printing plate is used. If a four color printing press is used to produce a color image, then as many as four printing plates are needed to produce the color image. Each printing plate designated for a different color, and to be used together to print a particular image (the same print job) has the same or a similar imaged placed upon each plate as is well known in the art.
[0003] Platesetters are machines used to transfer an electronic image onto a printing plate, for subsequent use on a printing press. Platesetters often use laser based imaging systems to transfer an electronic image onto the plate, in a process called imaging. A typical laser imaging system employs many individual laser beams to image a printing plate. The plurality of laser beams used to image a plate, sometimes called writing beams, or just beams, often emanate from a moveable assembly referred to as an imaging head. An example of a multi-beam imaging head for an external drum platesetter is shown in FIG. 1. The optic energy produced by the laser (or lasers) is utilized to transfer an electronic image onto a printing plate that is photosensitive or thermally sensitive (including ablative) as is well know in the art.
[0004] Color images printed using a printing press such as a lithographic printing press are verified for quality prior to, and during printing. A measure of the quality of a printed color image is the presence or absence of artifacts in the image. Artifacts are undesired variations in the printed image, such as the well known banding phenomenon shown in FIG. 3. Many causes contribute to generation of artifacts in a printed image. Periodic artifacts, such as banding may be caused by repetitive equipment errors in the printing press itself, or in the equipment used during the pre-printing press phase of production, called prepress. Platesetters are an example of prepress equipment.
[0005] Image processing is often employed to compensate for equipment errors in an effort to remove artifacts from an image, or alternatively, to prevent artifacts from being formed in the image. U.S. Pat. No. 6,185,002 to Askeland et al is one example of where image data is manipulated to reduce artifacts such as banding. This intensive data manipulation carries a significant cost in terms of required computing power, memory, and additional software. This data manipulation step, or steps, serves to increase costs and reduce throughput in addition to changing the image via adding or deleting image pixels.
[0006] What is needed is a means to reduce or eliminate artifacts in a printed image without having to resort to expensive image processing methods that increase cost.
[0007] Further, it is also desirable to be able to reduce or eliminate artifacts without adding additional hardware to existing equipment.
SUMMARY OF THE INVENTION
[0008] The invention herein solves the problems described supra and others, by using a different starting beam of a multi-beam imaging head when imaging each printing plate designated for a unique color plane, subsequently used to print a given image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The following description may be further understood with reference to the accompanying drawings in which:
[0010] [0010]FIG. 1 is a schematic of a multi-beam imaging machine for imaging printing plates.
[0011] [0011]FIG. 2 is prior art showing how a printing plate is imaged.
[0012] [0012]FIG. 3 is an example of an artifact referred to as banding.
[0013] [0013]FIG. 4 demonstrates how multiple pixels (or dots) can be used to create a color image.
[0014] [0014]FIG. 5 shows one mechanism causing banding.
[0015] [0015]FIG. 6 shows how the invention herein reduces banding at the pixel level.
[0016] [0016]FIG. 7 shows how the invention herein is implemented on a platesetter.
[0017] [0017]FIG. 8 is the example of the banding artifact shown in FIG. 3 reproduced adjacent other figures to facilitate comparison with FIG. 9.
[0018] [0018]FIG. 9 is the sample image of FIG. 8 showing the utility of the invention herein by removing (or preventing) the banding artifact (from being formed).
[0019] [0019]FIG. 10 shows alternate embodiments of the invention.
[0020] The drawings are shown for illustrative purposes only, and are not to scale.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Though the following description of the invention herein is described in the context of an external drum platesetter, the application of the invention should not be limited to such. For example, the invention herein may also be employed on internal drum or flatbed platesetters, external or internal drum imagesetters and/or printing presses. Printing plate 34 may alternatively be a piece of film in lieu of a printing plate without deviating from the spirit of the invention. Further, the invention herein may be practiced with all types of printing plates, including but not limited to, aluminum, polyester, flexographic etc..
[0022] Referring to FIG. 1, printing plate 23 is mounted on an external drum 21 of a platesetter 20 . Plate 23 has an imageable area 24 that an image (not shown) is transferred onto using moveable imaging apparatus 25 , often referred to as an imaging head. Drum 21 is rotatable as shown by arrow 22 , which in conjunction with moveable imaging head 25 , the movement thereof shown by arrow 27 , operates to move a plurality of N imaging beams 26 over the entire imageable area 24 of plate 23 . The number N, of imaging beams provided by multi-beam imaging head 25 is not restricted. Imaging heads having 96 beams, or as many as 1088 beams are known.
[0023] Referring to FIG. 2, imageable area 24 can be viewed as consisting of many individual picture elements, or pixels, that must be imaged, or “turned on”. Though only a single row of pixels 28 are shown in FIG. 2, it is understood that the entire imageable area 24 consists of pixels. Imaging head 25 is shown having a plurality of imaging beams 26 aligned with the row of pixels 28 . The alignment is such that the first beam 32 of N beams is aligned with the first pixel 33 in the row of pixels 28 . An N beam imaging head can image a swath 29 having a width of N pixels. From this initial starting position, an image is transferred (imaged) onto plate 23 . The first beam used to image the first pixel 33 in this example is beam 32 , and is referred to as the starting beam. The starting beam as defined in this application, is the first beam, of a multi-beam imaging head, that is used to start imaging the first pixel of an image to be placed on image area 24 . In accordance with the invention herein, the starting beam may be a beam other than the first beam in a multi-beam array.
[0024] The plurality of beams 26 are moved down plate 23 due to rotation of the drum 21 forming a swath 29 on imageable area 24 . Note that though the swaths herein are described as vertical, or parallel to an edge of plate 23 , the swaths may also be helical due to the combined rotational movement of drum 21 and lateral movement of imaging head 25 . After swath 29 has been imaged, imaging head 25 is positioned to image the next swath 30 , and imaging is continued in this manner until the entire electronic image is placed on imageable area 24 , the last swath being swath 31 . Applicant notes that though three swaths are described, the number of swaths may be any number, and is dependent upon the size of the plate and number of imaging beam among other variables. The total number of swaths is independent of the invention herein.
[0025] Once plate 23 has been imaged, it may be further processed (e.g. developed) if required depending upon the type of plate before being used on a printing press. Plate 23 is designated for use with only one color of ink, called a color plane, and is used on a printing press. Consequently, an additional printing plate must also be imaged with the same or similar image for each primary color used in the subsequent printing process for a given print job as is well known in the art. Applicants note an image placed on a printing plate designated for a particular color, may not be identical to an image placed on a printing plate designated for a different color plane as is well known in the art. A printing plate designated for use with a particular color on a printing press is referred to as that particular color plate to avoid confusion with other plates. For example, a plate designated for use with the color yellow, is called a yellow plate even though the plate is not actually yellow in color.
[0026] When a color image is printed using multiple plates for the different colors as is known in the art, artifacts may be created.
[0027] Some types of artifacts may appear as a white line (or other color) in a color field or variations in intensity of a color field or fields. The color fields in which artifacts may appear are not limited to the primary color fields such as cyan, yellow, magenta (reddish) and black. Composite color fields may also be affected such as green. A green color field is created on a printing press by placing a yellow dot on a substrate with one printing plate, and then placing a cyan (a bluish color) dot on top of the yellow dot using a different printing plate. The two colors (composed of ink, wax etc.) mix yielding green.
[0028] Referring to FIG. 4, the process can be visualized. A portion of a yellow printing plate 13 is shown consisting of nine pixels arranged in three columns 1 , 2 , and 3 , of three pixels each. Applicants point out a printers “dot” is composed of a plurality of pixels. The number of pixels per dot is dependent upon the various resolutions required or used (e.g. dpi, number of line screens etc.) for a given type of printing technology and may or may not be in the range of ˜20-64 pixels per printers dot. Pixels are typically imaged on a printing plate using a platesetter, and dots are typically printed on a substrate (e.g. paper, cardboard, bumper sticker, cloth etc.) using a printing press. Again referring to FIG. 4, a portion of a cyan printing plate 14 is shown consisting of nine pixels arranged in three columns 1 ′, 2 ′, and 3 ′, of three pixels each. After plates 13 and 14 are imaged in the prepress phase of production, the plates are installed onto a printing press (not shown). Plate 13 is used to place yellow ink onto substrate 15 in the nine-pixel pattern shown. Plate 14 is then used to place cyan ink onto substrate 15 , on top of the yellow nine-pixel pattern, also in the same nine-pixel pattern shown. The resulting nine-pixel pattern on substrate 15 has a green color. Though the figures are black and white, the additive effect is similar in that the gray color of substrate 15 is darker than either plate 13 or 14 and represents the result of adding yellow and cyan for illustrative purposes only.
[0029] Referring to FIG. 5, one mechanism that creates artifacts will be shown. The type of artifact to be shown is banding which can be a variation in color intensity, but well may be another type. Each column of pixels shown in FIGS. 4 - 6 corresponds to a unique, single imaging beam emanating from N beam imaging head 25 . For this example, in FIG. 5, the first three beams of multi-beam imaging head 25 are used to image pixel columns 1 , 2 , and 3 . Also for this example we assume the second beam has very low optic power output such that pixels imaged by the second beam are not “fully imaged” resulting in a light color being produced when the plate is used for printing. This is shown on plate 13 a by the columns of imaged pixels 4 a and 6 a being darker than column 5 a. Since the same physical imaging beams, the first three beams in this example, are used to image all color plates, the same problem also exists on the cyan plate 14 a as shown by imaged pixel columns 7 a and 9 a being darker than 8 a. The net result is that when plates 13 a and 14 a are used to print the image on substrate 15 a, column 11 a of FIG. 5 is a much lighter green than columns 10 a and 12 a. This phenomena occurs at the pixel level on printing plates 13 a and 14 a, and appears as a series of alternating light and dark bands 37 , 38 across the printed image 36 as shown in FIG. 3.
[0030] An inventive step herein is demonstrated in FIGS. 6 and 7. When imaging plate 13 b (designated for use with the color yellow on press) is imaged, the starting beam in this example is actually the second beam 39 of multi-beam imaging head 25 . This is seen in FIG. 6 because beam 39 is aligned with the first column of pixels 1 on plate 13 b. FIG. 6 shows imaged pixel column 5 b being lighter in color than imaged pixel columns 4 b and 6 b similar to the previous example. However, different from the previous example, the starting beam for cyan plate 14 b is actually the fourth beam 48 of multi-beam imaging head 25 . Since, in this example, the fourth beam 48 has normal optic power output, imaged pixel column 8 b has the same color intensity as adjacent imaged pixel columns 7 b and 9 b. Note that the starting beams for yellow plate 13 b and cyan plate 14 b are not the same, therefore a different set of imaging beams are used to image each color plate. This dilutes the effect of any imaging beam of multi-beam imaging head 25 that may be low in optic power or may be out of focus or have other spatial errors. The result of this inventive method is that the color field created on substrate 15 b by a printing press using plates 13 b and 14 b is much more uniform as shown in FIG. 6. Printed color column 11 b is much closer in color intensity to adjacent printed color columns 10 b and 12 b, than printed color column 11 a is to columns 10 a and 12 a in FIG. 5.
[0031] In a preferred embodiment, a different start beam is used for each printing plate that is designated for use with a unique color plane when used on a printing press for a particular print job. In other words, if a print job (e.g. a magazine cover) requires four colors on press, then the four required printing plates (corresponding to the four required colors) are imaged on a imaging machine using a different starting beam for each plate. The sequence that the starting beams are selected from plate to plate, may be random, pseudo-random, fixed offset, or even sequential. For example, if four plates are required (e.g. designated for yellow, cyan, magenta, and black) the starting beams could be 1, 13, 21, and 4 respectively. In a preferred embodiment, a random beam selection process is utilized
[0032] Referring to FIG. 7, the invention herein is shown compared to the previous technique of using the first beam 32 as the starting beam and using all available beams for all plates. The starting beam 40 is actually the third imaging beam of N beams in multi-beam imaging head 25 . This means that the first two beams 32 , 39 are not used to image this particular plate. In a preferred embodiment, the first two beams 32 , 39 are not used to image only the first swath 44 , and all N beams are used to image the remaining swaths (except for residual swath 47 ). Since a subset of the full number of N beams is used to image at least some of the plates, some pixels 42 remain that would otherwise have been imaged if the full number of N beams were utilized. Consequently, at least one additional swath 47 may be required to fully image the imageable area 24 of plate 23 . Using the inventive technique herein, swaths 44 - 47 are required verses swaths 29 - 31 to image the same imageable area 24 . Each color printing plate, each of which is imaged using a different starting beam (or different set of beams) may each require a different number of swaths in order to fully image each plate.
[0033] [0033]FIG. 9 shows the same image as FIG. 3 (reproduced as FIG. 8 to facilitate comparison) with the exception that the image in FIG. 9 shows the effect of implementing the invention herein. FIG. 8 clearly shows the banding phenomenon on what is otherwise a uniform color image. Alternating bands of light 37 and dark 38 color intensity are seen in the image 36 of FIG. 8 and are absent in the image 36 a of FIG. 9. FIGS. 8 and 9 are macro (whole image) representations of the micro representations (pixel level of image) shown in FIGS. 4 - 6 . Even though some banding may still remain after implementing the inventive method herein, the residual banding is virtually undetectable to the human eye. The banding has essentially been obscured or hidden and is simply not perceivable to the unaided eye.
[0034] In a first alternate embodiment, the ending beam may be varied and the starting beam may be the same for each color plate. For example, referring to FIG. 10, starting beam 32 is used to image the first pixel 33 on each color plate (the imageable area 24 for only one plate is shown for clarity). However, the ending beam will be different for each color plate. One implementation of this alternate embodiment could be beams 1 to N are used to image a yellow plate, beams 1 to (N−1) used to image a cyan plate, beams 1 to (N−2) used to image a magenta plate, and beams 1 to (N−3) used to image a black plate. This is illustrated in FIG. 10 by beams 34 , 35 , and 41 shown as dotted lines indicating that one or more of beams 34 , 35 , or 41 is not used to image some of the plates.
[0035] A result of the first alternate embodiment is the first swath of the printed image will still have banding since the same beams are used to image equivalent pixels on all the plates. However, the remaining portion of the printed image will have the banding removed (or obscured). Since a single swath is actually a very small portion of the total printed image, the banding in the first swath may not be prominent.
[0036] A second alternate embodiment uses different starting and ending beams for each color plate. However, the printed image will still have banding which may be acceptable in some print runs.
[0037] The previously described embodiments are variable swath techniques on a plate to plate basis. A third alternate embodiment is to use any of the previously described embodiments, wherein a given color plate (e.g. the yellow plate) has the starting beam, ending beam, or both starting and ending beams varied on a swath to swath basis within the same plate. The result would be some residual banding may remain, which may be acceptable depending on the particular print run.
[0038] Though the invention herein has been described for use with printing systems that use printing plates, the invention is not limited to such. The invention herein may also be adapted for use with color printers that do not use printing plates, but use separate color cartridges, such as inkjet printers, laser printers or any multi-beam scanning system.
[0039] Further, the invention is also suitable for use with on-press plate making systems (alternatively referred to as plateless printing systems) where temporary printing plates are actually created on a cylinder (or other support surface).
[0040] Those skilled in the art will appreciate that numerous modifications and variations may be made to the above disclosed embodiments without departing from the spirit and scope of the present invention. | A method for reducing artifacts in a color printed image, that are perceivable by the naked eye, includes using a different imaging beam to start imaging each printing plate that is used for a different color plane. Alternatively, a different set of imaging beams may be used to image each printing plate used for a different color plane. The method does not require manipulating image data. The method diffuses some errors throughout the printed image and prevents some errors from being imaged and/or printed which reduces or eliminates the visible perception of artifacts. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority of U.S. Provisional Application No. 60/383,076, filed May 23, 2002.
FIELD OF THE INVENTION
This invention relates to pumps, and, more particularly, to pumps having highly-accurately controlled dosing.
Highly-accurate pumps are known in the prior art for repeatedly delivering doses within exacting tolerances, even at extremely low-dose volumes. For example, with reference to International Patent Application No. PCT/US00/23206, published as International Publication No. WO 01/14245 on Mar. 1, 2001, a pre-compression pump system is shown for repeatedly delivering microdoses of fluid. The pump of this design utilizes a stationary seal which bears against a moving valve stem. The stroke of the pump is defined by the length of a constant-diameter portion of the valve stem which terminates at a lower extreme defined by a plurality of circumferentially-spaced recesses. In this manner, the seal member remains in constant sealing engagement with the valve stem with fluid bypassing the sealing member via the recesses to re-charge the pump chamber. With this structural configuration, accurate control of dosing can be achieved through accurate dimensioning of the valve stem and recesses. In a different approach, U.S. Pat. No. 5,277,559, which issued on Jan. 11, 1994 to the inventor herein, a pump with a sliding seal is provided which moves, at least in part, with a valve stem that selectively controls flow through the pump.
SUMMARY OF THE INVENTION
With the subject invention, pump systems are provided which allow for highly-accurate dose control. In one embodiment, a pump system is provided which includes a pump body having a first chamber defined therein; a valve stem disposed to slide within at least a portion of the pump chamber, the valve stem having a constant-diameter stroke portion interposed between reduced-diameter portions; and at least one stationary sealing member immovably affixed to the pump body formed to sealingly engage the stroke portion of the valve stem. The sealing member is also formed to not engage the reduced-diameter portions of the valve stem. With the sealing member sealingly engaging the stroke portion of the valve stem, a portion of the first chamber of the pump body is isolated or substantially isolated from other portions of the chamber. Accordingly, fluid trapped within the first portion may be compressed and dispensed.
In a second embodiment, a pump system is provided which includes a pump body having a first chamber defined therein; a piston disposed to slide within at least a portion of the first chamber, the piston having a constant-diameter stroke portion interposed between reduced-diameter portions; and at least one stationary sealing member immovably affixed to the pump body formed to sealingly engage the stroke portion of the piston. The sealing member is also formed to not engage reduced-diameter portions of the piston. With the sealing member sealingly engaging the stroke portion, a portion of the first chamber is isolated or substantially isolated from other portions of the first chamber. Again, as with the first embodiment, fluid trapped within the first chamber can be pressurized in being dispensed.
With both embodiments, the volume of the administered dose is controlled by the stroke length, which, in turn, is a function of the dimensioning of the constant-diameter stroke portion and the dimensioning of the sealing member. Advantageously, with the subject invention, a minimal number of tolerances can be implicated in controlling dosing volume.
In third and fourth embodiments, “in-line” pump systems can be provided having an exit aperture extending along the longitudinal axis of the pump system (such as in the manner of a nasal spray). These embodiments each include a valve stem and operate in the same basic manner as the first embodiment.
These and other features will be better understood through a study of the following detailed description and accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIGS. 1-3 depict a first embodiment of a pump system formed in accordance with the subject invention herein;
FIGS. 4-6 show a second embodiment of a pump system formed in accordance with the subject invention herein;
FIG. 7 is a front elevational view of a possible external configuration of a pump system;
FIGS. 8-9 show a third embodiment of a pump system formed in accordance with the subject invention herein; and
FIG. 10 shows a fourth embodiment of a pump system formed in accordance with the subject invention herein; and
FIGS. 11A-11C are top, side and bottom views, respectively of a swirl plug which may be utilized in connection with the subject invention.
DETAILED DESCRIPTION
Pump systems are described herein having a relatively low number of dimensions critical for controlling dosing. The pump systems are particularly well-suited for use with ophthalmic medication, which can be repeatedly and accurately dosed in relatively small doses (less than or equal to 50 microliters). In manufacturing, a low number of critical dimensions translates to a small range of net inaccuracy (e.g., combined deviations within acceptable tolerances).
With reference to FIGS. 1-3, a first pump system 10 is shown in cross-section having an outer generally cylindrical wall 12 . A bulkhead 14 extends inwardly from the wall 12 to define an upper limit of a reservoir 16 . In a preferred embodiment, the reservoir 16 is not vented to atmosphere, and, thus, pressure piston 18 is provided to avoid the formation of a vacuum in the reservoir 16 . The pressure piston 18 is urged towards the bulkhead 14 by spring 20 and is responsive to reductions of fluid volume in the reservoir 16 (such as with fluid being drawn therefrom). The spring 20 is mounted onto, and acts against an end plate 22 , that is connected to the wall 12 using any technique known by those skilled in the art, such as with a snap fit. If required, and as will be recognized by those skilled in the art, venting may be provided between the wall 12 and the end plate 22 , and may be provided similarly in the further embodiments described below.
Apertures 24 are defined through the bulkhead 14 through which fluid may be drawn from the reservoir 16 . A solid disc-shaped support plate 26 is defined at the center of the bulkhead 14 , with the apertures 24 being spaced circumferentially thereabout. Splines 28 extend upwardly from the support plate 26 and between the apertures 24 , and a solid wall 30 encircles the splines 28 . The wall 30 terminates in a cantilevered tapered seal ring 32 . A lower pump chamber 34 is defined amidst the support plate 26 , the wall 30 , and the seal ring 32 , which is in fluid communication with the reservoir 16 via the apertures 24 .
Casing 36 is mounted onto the wall 30 and is formed with a cylindrical portion 37 and an upper aperture 38 . An upper pump chamber 40 is defined within the casing 36 and is in communication with the lower pump chamber 34 . A valve stem 42 is disposed within the pump chambers 34 and 40 and is urged away from the support plate 26 by a stem spring 44 . A slidable piston cap 46 extends through the aperture 38 and has annular seal members 48 in sealing contact with the cylindrical portion 37 of the casing 36 . The piston cap 46 further includes an inner annular passage 50 formed between the stem 42 and the piston cap 46 which is in fluid communication with an exit aperture 52 located at the upper extremity of the cap 46 . The stem 42 is formed with a top 54 that terminates in a tapered portion 56 shaped to be seated in, and form a seal with, the exit aperture 52 . The stem spring 44 is selected such that the tapered portion 56 is sufficiently acted on to form an acceptable seal with the exit aperture 52 .
A nozzle actuator 58 is mounted onto the piston cap 46 so as to move unitarily therewith. Passageway 60 communicates the exit aperture 52 with a discharge chamber 62 in which is located a discharge piston 64 . The discharge piston 64 includes circumferential seals 66 which prevent fluid from leaking beyond the discharge chamber 62 . The discharge chamber 62 is in fluid communication with a discharge nozzle 68 .
A stem 70 of the discharge piston 64 has a seal surface 72 formed at an end thereof which coacts with a tapered surface 74 of the actuator 58 to form a seal for the discharge chamber 62 . A discharge spring 76 urges the seal surface 72 into engagement with the tapered surface 74 . To facilitate assembly, an end 77 of the nozzle actuator 58 may be formed open so that the discharge piston 64 and the discharge spring 76 may be mounted therein and covered with a plug 78 which may be fixed using any technique known to those skilled in the art, such as with an interference fit using detents 80 .
In use, the nozzle actuator 58 is caused to be pressed downwardly, as represented by the arrow A. As such, the piston cap 46 moves unitarily with the actuator 58 , causing the top 54 to also move downwardly. Upon traversing a stroke distance S, an enlarged portion 82 of the top 54 engages the seal ring 32 , thereby sealing the lower pump chamber 34 from the upper pump chamber 40 . With further downward movement, the seal ring 32 is caused to flex outwardly (forming a seal with the enlarged portion 82 ) and the volume of the upper pump chamber 40 is decreased. With further volume decrease, the pressure of the fluid trapped within the upper pump chamber 40 increases and acts upon upper face 84 of the enlarged portion 82 . As the actuator 58 and the piston cap 46 continue downwardly, pressure builds in the trapped fluid. When pressure overcomes the biasing force of the stem spring 44 , the tapered portion 56 of the stem 42 moves downwardly and away from the cap 46 , thereby exposing the exit aperture 52 (FIG. 2 ). Fluid then is forced into the discharge chamber 62 where pressure therein is increased until the seal members 66 are forced rearwardly against the force of the discharge spring 76 . As a result, discharge nozzle 68 is exposed and pressurized fluid from the discharge chamber 62 is dispensed therefrom. When the enlarged portion 82 goes through, and beyond, the seal ring 32 , the upper pump chamber 40 comes into fluid communication with the apertures 24 via the lower pump chamber 34 , thereby reducing fluid pressure in the upper pump chamber 40 (FIG. 3 ). This allows the stem spring 44 to urge the stem 42 upwardly into sealing engagement with the exit aperture 52 . With the exit aperture 52 closed, fluid pressure in the discharge chamber 62 decays with fluid being dispensed through the discharge nozzle 68 , allowing the discharge spring 76 to shut off the discharge nozzle 68 . The release of the actuator 58 allows the stem spring 44 to return the stem 42 and the piston cap 46 to their original rest positions. As the enlarged portion 82 passes upwardly through the seal ring 32 , it creates a transient vacuum sufficient to draw a volume of fluid through the apertures 24 equal to the amount dispensed. The pressure piston 18 assists the transient vacuum in urging fluid into the lower pump chamber 34 . This assures total fluid replacement. The volume of the reservoir 16 is decreased in response to the fluid which is drawn therefrom as the pressure piston 18 is pushed upwardly responsively by the spring 20 .
The size of the dose dispensed by the pump system 10 is basically a function of four critical dimensions of the pump system 10 . Particularly, the length of the enlarged portion 82 (“x”); the length of flat surface 83 of the seal ring 32 (“y”); the diameter of the enlarged portion 82 (“d”); and, the inner diameter of the casing 36 along cylindrical portion 37 (“z”). By minimizing the tolerances of these four dimensions, high-level of control over doses administered by the pump 10 can be achieved. As will be appreciated by those skilled in the art, dimension “y” (i.e., the flat surface 83 ) can be made so small (0.005 in) that dimensional variation may be practically zero and three dimensions actually control dosage of the pump system 10 (e.g., the flat surface 83 could be made as a small radius making this dimension a point contact with neglible width).
With reference to FIGS. 4-6, a second embodiment of a pump system is depicted therein in cross-section and generally designated with the reference numeral 100 . Many of the components of the pump system 100 are the same as, or similar to, that of the pump system 10 described above, and are designated with like reference numerals herein. The pump system 100 , like the pump system 10 , is dependent upon four critical dimensions. The discussion below will focus on the differences from the pump system 10 in structure and operation.
A pressure piston 18 ′ is provided which is spring-biased by a spring 20 in the same fashion as the pressure piston 18 . However, the pressure piston 18 ′ is shown to have a generally planar surface in contact with the reservoir 16 , whereas the pressure piston 18 is formed with a tapered portion. The shape of the pressure piston 18 , 18 ′ is preferably selected to match the shape of the corresponding bulk head. In FIG. 1, the bulkhead 14 is formed with a tapered portion, whereas in FIG. 4, a bulkhead 14 ′ is provided which is generally planar. In this manner, the pressure piston 18 , 18 ′ may efficiently urge fluid out of the reservoir 16 .
A central disc-shaped support plate 26 ′ is formed in the center of the bulkhead 14 ′ with apertures 24 ′ being formed circumferentially thereabout. An inner annular wall 28 ′ extends from the support plate 26 ′, located radially inwardly of the apertures 24 ′. The wall 28 ′ terminates in a seal ring 32 ′. A locator pin 102 may also be provided which extends upwardly from the center of the support plate 26 ′ to provide support for the spring 44 . A lower pump chamber 34 is defined admist the support plate 26 ′, the wall 28 ′ and the seal ring 32 ′.
The pump system 100 utilizes a piston 42 ′ which has a different configuration from the stem 42 of the first embodiment. The piston 42 ′ is disposed to extend through an aperture 38 of casing 36 so as to be slidable relative thereto. Piston seals 48 ′ provide a seal against the cylindrical portion 37 of the casing 36 during sliding movement of the piston 42 ′. The spring 44 urges the piston 42 ′ upwardly and away from the support plate 26 ′ with annular shoulder stop 104 defining the upper extent of movement of the piston 42 ′ in contacting the casing 36 . A cylindrical wall 106 extends upwardly from the shoulder stop 104 and through the aperture 38 , and a central passageway 108 is defined within the wall 106 . A check valve seat 10 is defined at an end of the passageway 108 which communicates with an inlet passageway 112 . A check valve 114 is disposed in the passageway 108 so as to seat on the inlet check valve seat 110 and regulate flow through the inlet passageway 112 . A lower annular piston ring 116 is defined about the inlet passageway 112 . The piston ring 116 is formed to engage the seal ring 32 ′ upon sufficient downward movement of the piston 42 ′.
A nozzle actuator 58 ′ is rigidly fixed to the piston 42 ′ so as to move unitarily therewith. The nozzle actuator 58 ′ is generally the same as the nozzle actuator 58 . The nozzle actuator 58 ′ is mounted on the piston 42 ′ in any manner so as to move unitarily therewith. In addition, an elongated block 118 is preferably provided which extends from the nozzle actuator 58 ′ and into the passageway 108 . In this manner, a reduced-diameter channel 120 is formed through the block 118 which communicates with passageway 60 and having a much smaller cross-section than the passageway 108 .
In use, the nozzle actuator 58 ′ is caused to translate downwardly (as shown by the arrow A), causing commensurate movement of the piston 42 ′. With sufficient movement, the piston ring 116 engages the seal ring 32 ′ and causes the lower pump chamber 34 to be sealed from the upper pump chamber 40 . With further downward movement of the piston 42 ′, the seal ring 32 ′ is caused to deflect outwardly, maintaining the seal between the pump chambers 34 and 40 intact. Further downward movement of the piston 42 ′ causes volume reduction of the lower pump chamber 34 , and an increase in pressure therein. With a sufficient increase in pressure, the check valve 114 is caused to lift from the valve seat 110 and pressurized fluid is forced through the inlet passageway 112 , the channel 120 and the passageway 60 to act on the discharge piston 64 (FIG. 5 ). The fluid is discharged form the discharge chamber 62 , in the same manner as described with respect to the pump system 10 . When the piston ring 116 goes through, and beyond, the seal ring 32 ′ (FIG. 6 ), pressure decays, the discharge piston 64 returns to its closed state, and the check valve 114 returns to its seated position on the valve seat 110 . With release of the nozzle actuator 58 ′, the spring 44 urges the piston 42 ′, and the nozzle actuator 58 ′, upwardly to the rest state shown in FIG. 4 . As the piston 42 ′ separates from the seal ring 32 ′, fluid is drawn from the reservoir 16 .
The four critical dimensions in the pump system 100 are the outer diameter x of the piston 42 ′; the diameter y of the seal ring 32 ′; the length t of the diameter x; and, the length z of flat surface 83 ′ on the seal ring 32 ′. The “z” dimension can be a radius or a small flat (0.005 inches); as such, dimensional variation is practically zero making three dimensions control dosage.
With reference to FIG. 7, a possible external configuration of a pump system is shown, which may be either the pump system 10 or the pump system 100 . Although the discharge nozzle 68 is shown to be covered in both FIGS. 1 and 4; it is in fact exposed, as shown in FIG. 7 . It is critical that the nozzle 68 not be covered by the wall 12 at a location where fluid is to be discharged therefrom.
With reference to FIGS. 8-9, a third embodiment of a pump system is depicted therein in cross-section and generally designated with the reference numeral 200 . The pump system 200 has the same basic structure and operates in the same basic manner as the first embodiment described above. However, the pump system 200 is an “in-line” dispenser having an exit aperture extending along the longitudinal axis of the pump system, such as in the manner of a nasal spray. Like reference numerals refer to identical or similar components described above.
The pump system 200 includes the exit aperture 52 formed in the piston cap 46 as with the first embodiment. However, the exit aperture 52 acts as a dispensing aperture for this embodiment in contrast to the first embodiment. Thus, fluid dispensed from the pump system 200 is dispensed along the longitudinal axis of the pump system 200 (which is coincident with the longitudinal axis of the stem 42 as shown in FIG. 8 ). To provide for actuation of the pump system 200 , actuator 202 is provided having finger grips 204 formed to be depressed by the pointer and middle fingers of a user. The actuator 202 is rigidly mounted to the piston cap 46 about shoulder 206 . With downward movement of the actuator 202 , the pump system 200 works in the same manner as described above. For illustrative purposes, as shown in FIG. 9, with downward movement of the actuator 202 , the stem 42 engages the seal ring 32 to form a seal therewith resulting in eventual separation of the stem 42 from the cap 46 , with exposure of the exit aperture 52 for dispensing pressurized fluid from the upper pump chamber 40 . Further downward movement of the actuator 202 results in pressure decay after a dose has been administered and full passage of the enlarged portion 82 beyond the seal ring 32 results in subsequent recharging of the pump system 200 . A release of the actuator 202 allows for return of the valve stem 42 to its rest position as shown in FIG. 8 .
FIG. 10 shows a fourth embodiment of the subject invention which is a variation of the third embodiment. Pump system 300 is also an “in-line” pump system which utilizes valve stem 42 , as in the first and third embodiments described above. Here, however pressure piston 302 applied to the reservoir 16 is applied in a downward motion to urge fluid up through tube 304 , having a passage 306 formed therein, and into the lower pump chamber 34 . Also, a swirl plug 308 may be provided between the piston cap 46 and actuator 310 . Various swirl plug configurations are known in the prior art. As an exemplary embodiment, as shown in FIGS. 11A-11C, the spray plug 308 may include radiating channels 312 . When fluid goes through the channels 312 and into the center of the plug 308 , a swirling motion is imparted to the discharging fluid, causing the fluid to break up into a spray pattern through nozzle 314 . In all other respects, the pump system 300 is essentially the same as the third embodiment.
As is readily apparent, numerous modifications and changes may readily occur to those skilled in the art, and hence it is not desired to limit the invention to the exact construction operation as shown and described, and accordingly, all suitable modification equivalents may be resorted to falling within the scope of the invention as claimed. | Pump systems are provided which allow for highly-accurate dose control. The pump systems may be provided with a valve stem or a piston, either having a constant-diameter stroke portion interposed between reduced-diameter portions. At least one stationary sealing member immovably affixed to a pump body is also provided formed to sealingly engage the stroke portion of the valve stem or the piston. The sealing member is also formed to not engage the reduced-diameter portions. As such, the volume of the administered dose is controlled by the stroke length, which, in turn, is a function of the dimensioning of the constant-diameter stroke portion and the dimensioning of the sealing member. Advantageously, with the subject invention, a minimal number of tolerances can be implicated in controlling dosing volume. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a sewing control system for sewing machine which counts the number of works sewn at each sewing process to control the output of works to be sewn.
In the prior art sewing control system, the operator operates the lever of a mechanical counter provided on the sewing machine table to provide a counter input everytime he sews one work. This complicates the sewing operation. The operator may often err in inputting the count or fail to input the count.
Heretofore, a system has been known in which the operator operates an electrical switch provided on the sewing machine table everytime he sews one work to input the number of works sewn to a counter in a central control unit. Like the above system, however, this system renders the sewing operation complicated. Similarly, the operator may often err in inputting the count or fail to input the count.
Heretofore, a system has also been known which counts the number of works sewn by counting thread cutting signals or wiper signals from the sewing machine.
However, when a thread cutting takes place in the course of sewing, accurate data can not be obtained, since a thread cutting signal for cutting a thread supplied by a pedal operation or wiper signal also is inputted to the counter as a count of the number of work sewn. This system is also disadvantageous in that the operator must operate a correct switch to correct this error.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an excellent sewing control system which enables automatic and accurate counting of the number of works sewn at each sewing process without the need of input or correction by the operator.
The present sewing control system is provided with a count circuit for counting signals synchronized with the rotation of the sewing machine, a memory circuit for storing a reference value, a comparator circuit for comparing the output from said count circuit with said reference value, an initializing circuit for initializing said count circuit only when said comparator circuit outputs a comparison after said reference value is stored, and a circuit for outputting a sewing finish signal as a data on the number of works sewn only when said comparison output is generated.
Thus, the present sewing control system enables automatic generation of sewing finish signal when the operator finishes sewing so that accurate data on the number of works sewn can be automatically obtained. Unlike the prior art system, the present system does not require that the operator operates a counter lever or electrical switch everytime he finishes sewing to input sewing finish. This prevents the operator from erring in inputting the count or failing to input the count. This system does not render the sewing operation complicated and thus greatly improves the working efficiency. Furthermore, even if the thread breaks in the course of sewing, the sewing finish signal can be prevented from being generated until sewing is finished, thus providing accurate sewing finish data (data on the number of works sewn). Thus, the present sewing control system has a number of excellent effects.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the essential part of an embodiment of the present invention; and
FIG. 2 is a view illustrating the operation of the embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention will be described hereinafter by referring to the drawings. FIG. 1 mainly comprises a count unit 1 and a counter initializing unit 2. Specifically, shown at 5 in FIG. 1 is a switch which is connected to positive power source V DD through respective resistors at contacts A and B and connected to ground at common contact C. The switching contact A is connected to one input of NAND circuit 6. The output of NAND circuit 6 is connected to one input of AND circuit 7. The switching contact B is connected to AND circuit 9. The output of AND circuit 9 is connected to set terminal S of latch circuit 10. The output of the latch circuit 10 is connected to reference input terminal of comparator circuit 12. The output of needle position generation circuit 14 is connected to counter 15. The output of the counter 15 is connected to comparison input terminal of the comparator circuit 12 and to subtraction circuit 17. The output of the subtraction circuit 17 is connected to the latch circuit 10.
The output of thread cutting generation circuit 18 is connected to the other input of the AND circuit 9 and to the other input of the AND circuit 7. The output of the thread cutting generation circuit 18 is connected to reset terminal R 2 of flip-flop 20. Connected to set terminal S of the flip-flop 20 is the output of step-on generation circuit 21 which generates a signal for driving the sewing machine. Connected to the other reset terminal R 1 is the output of initial reset circuit 22. The output of the flip-flop 20 is connected to edge generation circuit 23. The output of the edge generation circuit 23 is connected to the other input of AND circuit 25. Connected to the other input of the AND circuit 25 is the output of the NAND circuit 6. The output of the AND circuit 25 is connected to reset terminal R of the counter 15. The output of the AND circuit 7 is connected to output circuit 26. The output of the output circuit 26 is connected to output terminal 27.
FIG. 2 is a view illustrating the operation of an embodiment of the present invention. Shown in FIG. 2 is the process of sewing a collar of a white shirt or the like. Shown at α is the sewing start point and β the sewing end point. Let us here suppose that the edge of the collar is to be sewn in about 80 stitches between α and β.
The operation of the embodiment of the present invention having the above arrangement will be described hereinafter. When power is on, the initial reset circuit 22 generates high level signal (hereinafter referred to as "H signal") which then resets the flip-flop 20 which in turn outputs low level signal (hereinafter referred to as "L signal"). The operator then connects the switch 5 to the contact A to conduct first sewing. When the operator steps on the pedal of the sewing machine, the step-on generation circuit 21 outputs H signal which causes the flip-flop 20 to switch its output to H signal. This causes the edge generation circuit 23 to output an instantaneous H signal. Since L signal is outputted from the switch 5 at this time, H signal is outputted from the NAND circuit 6. This causes the AND circuit 25 to output an instantaneous H signal. The counter 15 is thereby reset so that its content is cleared to zero.
While in sewing, the needle position generation circuit 14 outputs needle position signal representing the position of the needle every stitch (e.g. signal representing needle drop) and the counter 15 counts the needle position signal.
The subtraction circuit 17 always subtracts a constant number from the content of the counter 15 so that the number of stitches is given a tolerance limit taking the dispersion of the quality of the works into account. In the present example, sewing is finished in 80 stitches, and the constant number to be subtracted is set at 5. Therefore, when 75 or more stitches are made, it is considered that one product is finished. When the operator finishes the first work, the counter 15 counts 80 while the subtraction circuit 17 counts 75. When the operator finishes sewing and then steps on the pedal of the sewing machine to cut the thread, the thread cutting generation circuit 18 generates a H level thread cutting signal. As this time the AND circuit 9 is kept open by the source voltage V DD . The thread cutting signal is given to set terminal of the latch circuit 10 which in turn latches the value 75 of the subtraction circuit 17 to automatically set the acceptable stitch number of the product. This is the feature of the present invention. The thread cutting signal causes the flip-flop 20 to be reset.
Since the AND circuit 7 is kept open by the output of the NAND circuit 6, the thread cutting signal is given to the output circuit 26 through the AND circuit 7. The output circuit 26 thereby inputs 1 as the number of the works sewn to the counter (not shown) of the central monitor unit connected to the output terminal 27.
To conduct the second and following sewing, the operator connects the switch 5 to the contact B. The AND circuit 9 is closed by L signal from the contact B. This blocks the signal to set terminal of the latch circuit 10 so that the content of the latch circuit 10 is kept at the acceptable stitch number (75). Since the value (80) of the counter 15 is larger than the value (75) of the latch circuit 10 at present, the comparator circuit 12 generates L signal which causes the NAND circuit 6 to output H level signal.
When the operator then steps on the pedal of the sewing machine, the step-on generation circuit 21 outputs H signal which causes the flip-flop 20 to output H level signal which in turn causes the edge generation circuit 23 to generate an instantaneous H signal. At this time, the AND circuit 25 is kept open by H signal from the NAND circuit 6. The value of the counter 15 is reset by H signal from the edge generation circuit 23 to zero. In this state, the comparator circuit 12 is at H level.
When the sewing continues, the counter 15 counts the needle position signal from the needle position generation circuit 14 one by one. When the value of the counter 15 exceeds the acceptable stitch number predetermined by the latch circuit 10 (the range between α and β shown by I in FIG. 2), the comparator circuit 12 outputs L signal. The NAND circuit 6 thereby outputs H signal which in turn causes the AND circuit 7 to open. When the sewing is finished and the operator then steps on the pedal of the sewing machine to cut the thread, the thread cutting generation circuit 18 outputs H level thread cutting signal which is then given to the output circuit 26 through the AND circuit 7. The output circuit 26 thereby inputs 1 as the number of the works sewn to the counter (not shown) of the monitor unit. For the following sewings, whenever the sewing is finished, 1 is automatically inputted to the counter of the monitor unit in the same manner as described above so that the total number of the works sewn is automatically counted.
In the event, in the sewing of a second or after piece of a product, that a thread break takes place by some external factor outside the acceptable stitch number range (I in Fig.2) as shown by II in FIG. 2, i.e. in the course of sewing and a thread cutting signal is generated by operating a pedal, an operation of the present invention is conducted. In this case, the thread cutting signal from the thread cutting generation circuit 18 is blocked by the AND circuit 7 so that it is not inputted to the output circuit 26. Specifically, since the count of the counter 15 is smaller than the value predetermined by the latch circuit 10, the comparator circuit 12 outputs H signal which causes the NAND circuit 6 to outputs L level signal which in turn causes the AND circuit to be closed. This blocks all thread cutting signals generated in the course of sewing.
Since the switch 5 is connected to the contact B as described above, the value of the latch circuit 10 is kept unchanged.
When the operator continues sewing from this thread break point (II in FIG. 2) or from several points before this break point, the counter 15 continues to count from the count made immediately before the thread break the needle position signals from the needle position generation circuit 14. Therefore, if the operator normally finishes sewing after the thread break in the course of sewing and then cuts the thread, the count of the counter 15 exceeds the value predetermined by the latch circuit 10. The comparator circuit 12 thereby outputs L signal. Therefore, a thread cutting signal is given to the output circuit 26 which in turn outputs 1 as the number of the works sewn.
While the above embodiment of the counter 15 has been referred to an addition system, the counter 15 may be a subtraction system. In the subtraction system, the subtraction circuit 17 is replaced by an addition circuit for adding a constant value. The comparator circuit 12 compares the stored value in the latch circuit 10 which has been provided by latching the output value from the addition circuit in the same manner as used in the above embodiment with the output value from the subtraction system counter 15. When the output value from the counter 15 is less than the stored value, the comparator circuit 12 generates L level comparison output signal. The output of the AND circuit 25 is connected to preset terminal of the counter 15. The output of the AND circuit 25 which is generated in the same manner as in the above embodiment operates to initialize the counter 15 to preset value.
While the above embodiment has been referred to thread cutting signal generated by the thread cutting generation circuit 18, the operation and effect of the present invention may be similarly attained by a sewing finish generation circuit for generating a sewing finish signal representing the sewing finish such as wiper signal and work holder lift signal.
While the above embodiment has referred to the needle position generation circuit 14 for generating the needle position such as needle drop, the operation and effect of the present invention may be similarly attained by a circuit for generating the signal synchronized with the rotation of the sewing machine main shaft such as sewing machine rotation signal and sewing machine speed signal.
While the above embodiment has been referred to the counter of the monitor connected to the output terminal 27, the counter may be connected to each output terminal 27. The display of the counter may be shared by the display of a digital clock so that both the time data and the counter output are given to the central monitor unit.
Furthermore, the comparator circuit may be of an analog system in which an operational amplifier is used.
Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been changed in the details of construction and the combination and arrangement of parts may be restored to without departing from the spirit of the scope of the invention as hereinafter claimed. | A sewing control system for a sewing machine which comprises a count circuit for counting signals synchronized with the rotation of the sewing machine, a memory circuit for storing a reference value, a comparator circuit for comparing said reference value with the output value from said count circuit, an initializing circuit for initializing said count circuit only when there is a comparison output from said comparator circuit after said reference value is stored, and a circuit for outputting a sewing finish signal as data on the number of the works sewn only when there is a comparison output. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to a solid-state laser device. More particularly, the present invention relates to a high-power laser device and a composite laser crystal incorporated by the device.
BACKGROUND OF THE INVENTION
[0002] Laser devices are broadly employed in various fields such as spectroscopy, measurement, fabrication, optical communication, clinical medicine and energy engineering. Although a laser medium can be any of gas, liquid or solid, use of a solid-state medium has become major for its handling convenience. Furthermore, in order to generate pumping light for exciting the laser medium, solid-state light sources such as laser diodes (LD) are replacing discharge tubes such as conventional flash lamps/flashtubes. Thus, laser devices having totally solid-state elements are now undergoing development.
[0003] A solid-state YAG laser for generating high-power laser light is used as a light source of a laser beam machine, which may perform fabrication such as drilling, welding, cutting and trimming on a work piece such as a metal, ceramic, wood, and a gem. Production of a high-power LD excitation YAG laser is associated with a problem of thermal birefringence generation. Thermal birefringence is a phenomenon which is caused when crystal rods are subjected to heat stress and which results in difference of the refractive indices of light between the radius vector and the vector perpendicular thereto. When such thermal birefringence occurs, a linearly polarized beam from a laser resonator may greatly be distorted depending on the polarization.
[0004] In order to compensate such thermal birefringence, two YAG laser crystals are arranged in tandem, and a 90° polarization rotator (half-wave plate) that rotates a plane of polarization by 90° is arranged between the two YAG laser crystals. Thermal birefringence results in two mutually perpendicular components having different refractive indices. By inserting the 90° polarization rotator between the two YAG laser crystal rods, the polarization direction of light propagating through the resonator in one way alters by 90° in front and back of the 90° polarization rotator. Accordingly, polarization components that differ for respective rods can be amplified in both directions. As a result, a biased amplification can be cancelled out, thereby preventing a thermal birefringence effect.
[0005] According to the above-described conventional method for compensating thermal birefringence, three optical elements (i.e., two YAG laser crystals and a 90° polarization rotator) need to accurately be aligned on an optical axis of a laser resonator. This alignment takes time for adjustment and the resulting laser device is poorly tolerant of oscillation.
[0006] The present invention solves such prior art problems, and has an objective of providing a solid-state laser device in which an alignment operation for arranging optical elements for compensating for thermal birefringence is easy, and which is mechanically highly stable by being tolerant of oscillation.
[0007] As a method for simplifying alignment of the three optical elements arranged in the laser resonator, the three optical elements are fixed on a single member in advance as a single unit which is then arranged in the laser resonator, thereby simplifying the alignment operation. This method, however, is unpractical since arranging three optical elements on a single member requires equal amount of labor to that for directly setting the optical elements in the laser resonator.
SUMMARY OF THE INVENTION
[0008] According to the present invention, the above-described objective is achieved by developing a composite laser crystal in which three optical elements (i.e., two YAG laser crystals and a 90° polarization rotator) necessary for compensating for thermal birefringence are formed into a single rod as the composite laser crystal to be arranged in a laser resonator. The two YAG laser crystals and a single half-wave plate (90° polarization rotator) are integrated as a single rod via optical contact, more preferably via diffusion bonding.
[0009] In a composite laser crystal of the present invention, a half-wave plate or a 90° polarization rotator is sandwiched between and integrated with two solid-state laser media. The 90° polarization rotator is an optical element which rotates any polarized light by 90°. On the other hand, a half-wave plate rotates specific linearly polarized light by 90° with respect to a plane of polarization. Preferably, the half-wave plate is integrated with the adjacent solid-state laser media via diffusion bonding.
[0010] A method for producing a composite laser crystal according to the present invention comprises the steps of: polishing end faces of a pair of Nd:YAG crystals and end faces of the quartz half-wave plate to obtain flat faces with a surface precision of λ/10 or less; arranging the half-wave plate between the pair of Nd:YAG crystals such that the flattened end faces of the crystals make contact with each other, and subjecting the resultant to pressure bonding under a pressure of 1 kg/cm 2 or higher; heating the crystals subjected to the pressure bonding at 400° C. or higher; and cutting out from the integrated rod obtained by the above steps, a laser crystal of a desirable shape. The surface precision is a value defined by twice the maximum deviation between an ideal reference surface and a polished surface as examined surface, and is represented with respect to HeNe laser wavelength (λ=632.8 nm). Accordingly, λ/10 is about 63 nm.
[0011] In order to bond an Nd:YAG crystal and a quartz via diffusion bonding, the surface precision of the faces to be subjected to diffusion bonding need to be λ/10 (i.e., 63 nm) or less. When the surface precision is rougher than this value, bonding does not take place. After passivation of the surface of crystal with acid, diffusion bonding requires heating at a temperature of 400° C. or higher for a predetermined time under a pressure of 1 kg/cm 2 or higher. When the pressure is lower than 1 kg/cm 2 , or the temperature is lower than 400° C., bonding with sufficient strength may not be achieved.
[0012] A solid-state laser device of the invention comprises an optical resonator, a pair of solid-state laser media arranged in the optical resonator, a polarization rotator arranged between the pair of solid-state laser media for rotating a plane of polarization by 90°, and a light source for exciting the laser media, wherein the pair of solid-state laser media and the polarization rotator are integrated by bonding the adjacent end faces thereof. The adjacent end faces are integrated via diffusion bonding.
[0013] By using the composite laser crystal of the invention, effect of thermal birefringence can be canceled out. Moreover, a laser device incorporating the composite laser crystal of the invention allows easy adjustment since there is no need of aligning individual optical elements in the laser resonator. As a result, the cost of production can be reduced and mechanical stability can be enhanced for being tolerant of oscillation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a schematic view showing an exemplary composite laser crystal of the invention;
[0015] [0015]FIGS. 2A to 2 C are views for illustrating an exemplary method for producing a composite laser crystal; and
[0016] [0016]FIG. 3 is a schematic view of a solid-state laser device of the invention which incorporates composite laser crystals.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Hereinafter, the present invention will be described with reference to the accompanying drawings.
[0018] [0018]FIG. 1 is a schematic view showing an exemplary composite laser crystal 10 of the invention. The composite laser crystal 10 is provided with two Nd:YAG crystals 11 and 13 , and a quartz (crystal) plate (90° polarization rotator) 12 sandwiched therebetween. The adjacent end faces of the Nd:YAG crystal 11 and the quartz plate 12 , and the adjacent end faces of the quartz plate 12 and the Nd:YAG crystal 13 are strongly bonded via diffusion bonding. As to the sizes, for example, when this composite laser crystal is to be incorporated by a laser resonator, as a laser medium for canceling out the effect of thermal birefringence to obtain a laser device for oscillating laser light at a wavelength of 1064 nm, the total length and the diameter of the composite laser crystal 10 are about 100 mm and about 4 mm, respectively, and the thickness of the quartz plate 12 used as the 90° polarization rotator is 6 mm.
[0019] [0019]FIGS. 2A to 2 C are views for illustrating an example of a method for producing the composite laser crystal shown in FIG. 1. As shown in FIG. 2A, Nd:YAG crystals 21 and 23 and a quartz 22 are cut out. End faces 21 a , 21 b ; 22 a , 22 b ; and 23 a , 23 b of the crystals are optically polished. Specifically, the end face 21 b of the Nd:YAG crystal 21 , the end faces 22 a and 22 b of the quartz plate 22 , and the end face 23 a of the Nd:YAG crystal 23 are polished to obtain flat surfaces with a surface precision of λ/10 (about 63 nm) or less.
[0020] Then, as shown in FIG. 2B, the end face 21 b of the Nd:YAG crystal 21 is made to contact with the end face 22 a of the quartz plate 22 , and the end face 23 a of the Nd:YAG crystal 23 is made to contact with the end face 22 b of the quartz plate 22 , thereby assembling a rod 20 . While applying a pressure of 1 kg/cm 2 or higher to both ends of the rod 20 , the rod 20 is heated at 500° C. After 5 hours, the Nd:YAG crystals 21 and 23 are strongly bonded to the quartz plate 22 at their end faces via diffusion bonding. Diffusion bonding allows optical bonding and mechanical integration, and is advantageous in that no damage is caused at the bonding faces since it does not require adhesion for bonding.
[0021] Finally, as shown in FIG. 2C, the rod 20 integrated via diffusion bonding is fabricated into a desirable shape to obtain a composite laser crystal 25 . The fabrication is performed by cutting out a cylindrical composite laser crystal 25 from the rod 20 with a core-drill, and then optical polishing both end faces. The composite laser crystal 25 is also subjected to non-reflective coating. Multiple composite laser crystals 25 may be cut out from the rod 20 .
[0022] [0022]FIG. 3 is a schematic view showing a solid-state laser device of the invention incorporating the composite laser crystal.
[0023] The solid-state laser device is provided with a total reflection mirror 31 and a partial reflection mirror 32 with a transmittance of about 70% as constituents of an optical resonator, the composite laser crystal 10 shown in FIG. 1 arranged therebetween, and a high-power LD laser 33 (wavelength: 808 nm) for generating pumping light surrounding the rod 10 . Lenses 34 and 35 are arranged between the composite laser crystal 10 and the total reflection mirror 31 and between the composite laser crystal 10 and the partial reflection mirror 32 , respectively. Since the composite laser crystal 10 is made of an integrated body of two Nd:YAG crystals 11 and 13 and the quartz plate (90° polarization rotator) 12 , there is no requirement of individual alignments of the three optical elements 11 , 12 and 13 as in a prior art device. Accordingly, it is very easy to assemble a solid-state laser device. Furthermore, since the three optical elements 11 , 12 and 13 are integrated as the composite laser crystal 10 , the alignment relationship between the three optical elements 11 , 12 and 13 does not change even when the device is subjected to oscillation. Therefore, the output characteristics of the solid-state laser device are not fluctuated by oscillation, maintaining extremely high stability.
[0024] Although a quartz plate is used as the 90° polarization rotator in the above-described embodiment, a half-wave plate may be used instead. Although diffusion bonding is employed for bonding the three optical elements to obtain the composite laser crystal in the above-described embodiment, an optical contact may be employed instead. Specifically, the bonding faces of the two rods previously cut out in desirable shapes and the 90° polarization rotator are polished to obtain a surface precision of λ/20 (about 30 nm); the three optical elements are assembled into a single rod by making the bonding faces thereof in contact; and a pressure of about 1 kg/cm 2 is applied to both ends of the rod, thereby bonding the three optical elements. Bonding by optical contact is easier than diffusion bonding. However, it requires a guide or the like due to its weak adhesive strength.
[0025] The solid-state laser device of the invention may be used as a light source of a laser beam machine which may perform fabrication such as drilling, welding, cutting and trimming on a work piece such as a metal, ceramic, wood, and a gem, or as a light source of a marking device. Alternatively, by converting the oscillation wavelength into a shorter wavelength by using non-linear optical elements, the solid-state laser device of the invention may be used as a light source of an exposure device or the like used for pattern exposure during a process of fabricating a semiconductor.
[0026] According to the present invention, a high-power solid-state laser can be obtained with easy alignment, which has enhanced mechanical stability and which does not cause thermal birefringent effect. | The present invention provides a solid-state laser device in which an alignment operation for arranging optical elements for compensating thermal birefringence is easy, and which is mechanically highly stable by being tolerant of oscillation.
A 90° polarization rotator 12 is arranged between and integrated with two solid-state laser media 11 and 13 via diffusion bonding to form a composite laser crystal 10 . The composite laser crystal 10 is arranged between constituents 31 and 32 of an optical resonator to form a solid-state laser device. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application 61/533,500 filed on Sep. 12, 2011, and to U.S. Provisional Application 61/545,671 filed on Oct. 11, 2011, each of which is incorporated herein in its entirety.
FIELD OF THE INVENTION
[0002] The dynamic risk predictor suite of the present invention identifies, prioritizes, and presents risks associated with an operation including a plant's operations in a manner that enables operating personnel (including management) at a facility to have a comprehensive understanding of the risk status and changes in the risk levels of processes, including in those facilities in which operations are monitored by a plurality of alarms or an alarm system. The hidden process near-miss information may be combined with related process data and/or data resulting from prior near-miss situations to permit preemptive corrective action to reduce or avert the occurrence of adverse incidents or catastrophic failure of a facility operation.
BACKGROUND OF THE INVENTION
[0003] Every low-probability, high-consequence adverse incident or catastrophic operational failure at any production or processing facility, such as a chemical plant, fluid-catalytic-cracking units (FCCU) at a petroleum refinery, or nuclear energy production plant, or even a biological facility or waste management facility, is preceded by many high-probability, low-consequence events, which are often recognized by alarms or as near-misses (Pariyani et al., Ind. Eng. Chem. Res. 49:8062-8079 (2010a); Pariyani et al., 20 th European Symposium on Computer Aided Process Engineering ( ESCAPE ) 28:175-180 (2010b)). Temperatures may go too high, tanks may run dry, power outages may cause all sorts of problems, or perhaps lead to flooding, and the like. An ideal risk management system at the plant will account for all these near-misses, and develop leading indicators to notify the operators in advance of undesirable incidents that are likely to happen. In particular, such knowledge becomes highly desirable for unmanned plants/facilities.
[0004] For example, in the following situations, the public has been harmed by industrial accidents, adverse events, and/or catastrophic failures that could have been avoided by an optimal alarm system. For example, the US government chemical safety board web site (www.csb.gov) is inundated with reports of accidents that took place in the chemical manufacturing facilities in the recent years that cost several lives, as well as property damage. The recurring themes in the outcome of analysis of these accidents are a) the lack of preventive maintenance, and b) the lack of attention to process near-misses. Moreover, every year billions of dollars are lost in the manufacturing industry due to “trips” (unexpected shutdowns due to malfunction of the equipment and/or control systems) at operational plants and facilities. For instance, there have been $6 billion/year losses recorded by US refineries from unexpected shut downs of crude and fluidized catalytic cracking (FCC) units.
[0005] An additional condition, which is frequently observed in most manufacturing or processing facilities, is silencing (muting) the alarms that are considered to be nuisance. These are alarms that are activated so often that that are considered to be of such little significance by the operators, that they are regarded as unimportant disturbances resulting from normal operations, so they are turned off or ignored like fire drills in office buildings. But such actions negate the value of the alarm system. For example, at an offshore refinery facility visited in 2011 by the inventors, most of the “low priority” alarms had been silenced. In fact, one of the reasons that the BP off shore accident in Gulf of Mexico in 2010 (where 11 people died and 17 were injured) was not identified in its early stages was because an alarm had been silenced because it had been going off in the middle of the night and awaking the workers.
[0006] Thus there is a need, not met until the present invention, for a “distributed control system” (DCS) and “emergency shutdown” (ESD) system databases and a variety of disclosed processes using an dynamic system that analyzes alarm and process data to assess operational risks as they change with time and to send alert signals and/or reports to address risk and/or alarm variables and to reduce or prevent adverse incidents or failures.
SUMMARY OF THE INVENTION
[0007] A methodology is provided by the present invention to properly manage alarms (and alarm data) and/or to assess operational risks at a manufacturing, production or processing facility, refinery or the like (herein generally referred to as “plant/facility” without intended specificity to type of plant or facility). The method is based upon measurement of one or more variables, and/or utilization and management of the concept of “hidden near-miss(es)” to identify a change or escalation, if any, in the probability of the occurrence of an adverse incident. The methodology of the invention is termed the Dynamic Risk Predictor Suite (DRPS), and is actually a combination of a plurality of subsets (also useful independently) of dynamically calculated leading risk indicators for dynamic risk management.
[0008] “Dynamically” means that the operation is monitored at frequent intervals. A “leading risk indicator” (LRI) is an indicator (or set of indicators) that provide information indication potential of upcoming or approaching risk(s). More specifically, LRI indicates the level of risk in a plant/facility operation or sub-operation at any given time, or over a period of time, or showing a change in risk levels from one point in time to another. The leading risk indicators used in the methodology are reported in different frequencies and formats to more readily assess different levels of plant/facility management, and offer significant improvements in safety and/or performance of the plant/facility by reducing losses in all areas.
[0009] Rapid advancements of technology means that companies can now store massive volumes of data collected on an ongoing basis in almost all continuous processes. However, the effective use of this data to improve safety, productivity and reliability of operational processes has been lagging, and current prior art methodologies are based on mathematical modeling and periodic visual inspections, with almost no use of ongoing collected data. As a result, it is an object of the present invention to provide significant innovation in identifying and managing process risks. Methods are provided to increase the capacity of plant/facility operators to understand developing risks before occurrence of a corresponding adverse incident, and to determine critical needs that must be addresses. This is accomplished by analyzing data collected during processes operations, extracting information therefrom, and providing actionable guidance to improve safety, reliability, and quality by calculating deviations from normal operations (i.e., operations functioning at a level deemed to be acceptable to plant/facility operators and/or owners), and classifying the operations based on the severity of the deviation.
[0010] Systems currently use visually observed or observable process near-misses. But the unobserved deviations that the present invention has found within the collected data, which were previously unknown or unrecognized, are collectively referred to herein by the above-referenced new term—“hidden process near-misses.” Thus, the present invention advantageously utilizes the information found in the hidden process near misses to identify potential problems in advance of their occurrence. A key feature of the invention therefore is to identify one or more risk as a measure of deviation of process conditions from normal operations, as identified by analyzing long-term behavior of the operation. The higher the deviations, the more serious are the risks. Process and alarm data over long periods of time (“long term periods”) are used to identify the behavior of normal operations that are acceptable to the plant/facility, thereby setting a baseline against which the new information from the combined near miss data including the hidden process near misses are compared and classified.
[0011] It is an object of the Dynamic Risk Predictor Suite to address: a) the lack of preventive maintenance at a plant/facility, and b) the lack of attention to adequately process near-misses at the plant/facility, including the lack of identification of hidden process near-misses and the lack of understanding the impact of “hidden process near-misses” (hidden operational risks). The Dynamic Risk Predictor Suite is designed to tackle both of these issues by a) prioritizing the alarms to identify alarms associated with high priority items for critical and/or immediate maintenance or modification of settings, b) identifying changes in alarms to pinpoint risk levels to the operations, and c) detecting possible trip/accident conditions in a timely manner so that plant/facility personnel (including management and operators, herein referred to general as “operators”) can address the critical conditions before damage is done during an incident—together this is referred to as “operational fitness” of the plant/facility. In fact, 50% of the cited $6 billion/yr in losses in all US refineries from unexpected shut downs of crude and fluidized catalytic cracking (FCC) unit can be eliminated thorough use of Dynamic Risk Predictor Suite.
[0012] Moreover, use of the DRPS System will permit an additional $600 million/year in estimated savings by eliminating preventable downtime of hydrogen plants in the US. In the European Union, this number is about $100×10 6 . In addition, the System will offer significant savings in lost opportunity costs. For example, in a major Gulf Coast accident, public estimates suggested that BP suffered $60 billion in total loss including of reputational losses. Accordingly, by conservatively reducing the probability of the occurrence of major accidents by as little as 10-25% over current levels, the Dynamic Risk Predictor Suite will significantly reduce the physical and the reputation loss that occurs whenever businesses suffer operational losses that result in loss of lives, or that directly and adversely affect the public.
[0013] The Alarm Fitness Module of the Dynamic Risk Predictor Suite operates by employing various new and novel methods to identify a variety of problems with operations, and to prioritize them for maintenance, as well as for management attention for desired time periods, on-demand or on real-time basis.
[0014] Thus, it is an object of the analytical tools of the present invention therefore are used to reliably provide information to the operator(s) and plant personnel at a plant/facility that there is a potential major adverse incident or problem likely to occur in the near future at the plant/facility.
[0015] In an embodiment of the invention, notification is provided regarding detection of the onset and/or presence of inherent faults, or special dangers, likely to lead eventually to adverse incident(s). Thus, the use of the present invention permits operators to be alerted up to several minutes or hours, or from 3-30 hours, from 12-24 hours, from 1-30 days or more, before potentially undesirable adverse events or problems are likely to occur. Thereafter, as the special-cause(s) of the alarm progresses, the possibility of accident(s) increases directly as the frequency of alerts are increased.
[0016] It is a further object to quantify the risks associated with the operations in a plant/facility and to maintain risk levels to a minimum, thereby improving safety, operability, reliability, and profitability.
[0017] An embodiment of the invention offers at least three main purposes. First, the System detects the presence of problematic alarms, and identifies safety and operability risks associated with the alarms or alarm systems. Information reported at regular times or on-demand provides advanced notification to the operators of problems at or preferably before onset, permitting the operators to prepare or take precautionary actions before the adverse events actually occur.
[0018] Secondly, the DRPS System sends alert signals to the operators in real time about approaching or instantly occurring incidents or trips, preferably before major adverse incidents. The “lead-times” (i.e., the time between the alarm alert-notification and the occurrence of the undesirable event/incident/failure) for alerts can vary from hours to seconds depending upon the severity and progression of a fault (or special-cause) and the nature of the fault. The inventors' studies have shown that the lead times range from several hours to 3 minutes or less. The lead time(s) can: (a) help the operators reduce or prevent the occurrences of undesirable events or adverse incidents by permitting appropriate avertive actions, and (b) better prepare the operators for tackling the consequences, should an undesirable adverse event incident occur.
[0019] Thirdly, the DRPS System identifies inherent and gradually developing (under the radar) or hidden risks, and alert the management of the facility of changes in operational risk levels at the plant/facility dynamically (in frequent intervals), with special messages sent when the risk levels change, or increase significantly. As used herein, “frequent intervals” or “frequently measured” with regard to process data means that process variables are monitored and reported at least every 1 second, and with regard to the alarm means that alarm data is monitored and reported at least every 1 microsecond.
[0020] It is an object of the implemented methods of the invention, as embodied in one or more subsystems of the Dynamic Risk Predictor Suite, to reduce at least 10%, up to 100%, of the probable occurrence of such adverse incidents or catastrophic failures before they occur as compared to presently available methods used by the same facilities. The general term “adverse incident(s)” is used herein to generally encompass all problems, adverse events, catastrophes and catastrophic failures of all types without limitation, if associated with a process system which may or may not be monitored by alarms.
[0021] Notably, the risk information provided by the alerts of this invention (just-in-time or on-demand risk indicators) are presumed to be important because they have been based on the data obtained from alarm and process measurements established by the plant/facility owners or operators at the plant/facility, and each therefore signifies an increased risk that is likely to eventually lead to adverse incidents and/or trips. As a result, the embodied methodology in the present invention advantageously offers the ability to effectively detect the most critical adverse incidents and trips, forewarning operators and management about the onset and progress of risks by utilizing the “hidden near-miss” data to flag alerts having lead times from several days or several hours to a few minutes. The Dynamic Risk Predictor Suite has been shown to provide extra protection, helping operators detect the incidents in real time and in advance of their occurrence, permitting appropriate corrective actions to be taken in advance of a significant adverse incident, failure, or loss of life, and as needed to prepare to tackle any resulting adverse consequences.
[0022] Additional objects, advantages and novel features of the invention will be set forth in part in the description, examples and figures which follow, all of which are intended to be for illustrative purposes only, and not intended in any way to limit the invention, and in part will become apparent to those skilled in the art on examination of the following, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE FIGURES
[0023] The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. Components which are essentially the same are given the same reference numbers through-out the drawings. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
[0024] FIG. 1 schematically illustrates the Alarm Fitness system AF, showing its component elements.
[0025] FIG. 2 schematically illustrates developing a classified chart with banded zones indicating significance levels, identifying or classifying frequency bands for meaningful interpretation, and analyzing data within a zone or zones for one or more time periods as part of the Advanced Frequency Analysis component of the Alarm Fitness system.
[0026] FIG. 3 graphically shows a classified alarm frequency chart that presents frequency of alarms per day for a period of 7 months.
[0027] FIG. 4 schematically illustrates the Finer Flood Analysis method of the Alarm Fitness system.
[0028] FIG. 5 schematically illustrates grading and ranking alarm floods in a given time period in the Alarm Attack Analysis method of the Alarm Fitness system.
[0029] FIG. 6 schematically illustrates a method AF203 to calculate “alarm attacks” in the Alarm Attack Analysis method.
[0030] FIG. 7 graphically shows alarm attacks, finer floods and standard alarm floods for a period of 20 minutes in the Alarm Attack Analysis method.
[0031] FIG. 8 schematically illustrates a method AF204 to grade and rank alarm attacks in a given time period.
[0032] FIG. 9 schematically illustrates a method AF301 to determine scale of an abnormal event, and to formulate an abnormal events matrix.
[0033] FIG. 10 graphically shows a 3×4 Abnormal Events matrix constructed to provide an example having the identified 4 levels of alarms as columns, and the 3 priorities of alarms (“High,” “Medium,” and “Low”) as the rows. Consequently, 12 scales of abnormal Alarm events are defined and represented by the 12 cells of the matrix.
[0034] FIG. 11 schematically illustrates a method AF302 to identify the riskiest abnormal events within a given time period and/or the riskiest abnormal events for a group of variables, within a time period.
[0035] FIG. 12 diagrammatically depicts scale determination of a typical abnormal event and a corresponding abnormal event matrix, wherein one peak is above the H2 alarm level. Scale of an abnormal event is defined in terms of stage of the abnormal event and criticality of the abnormal event.
[0036] FIG. 13 diagrammatically depicts another typical abnormal event, wherein there are two peaks above the H2 alarm level. Total time above the H2 alarm level, denoted by t 2 , equals m 1 +m 2 , wherein m 1 is time spent by variable above the H2 alarm level during its first peak, and m 2 is time spent by variable above the H2 alarm level during its second peak. t 2 is used in the risk score calculations.
[0037] FIG. 14 schematically illustrates a method for grading of variables based on riskiest abnormal events to determine a combined risk score.
[0038] FIG. 15 schematically illustrates a method AF401 to identify the riskiest alarm levels based on kick-off time analysis.
[0039] FIG. 16 schematically illustrates a method AF402 to identify the riskiest consecutive pair of alarm levels based on acceleration time analysis.
[0040] FIG. 17 schematically illustrates a method AF403 to identify the riskiest consecutive pair of alarm levels, based on a deceleration time analysis.
[0041] FIG. 18 schematically illustrates a method AF404 to identify the riskiest variables based on a “neighborhood time” analysis
[0042] FIG. 19 diagrammatically depicts the time segments and the riskiest relationships, showing that the time segments represent different characteristics of the alarms and variables.
[0043] FIG. 20 schematically illustrates a method AF405 to identify the riskiest alarm levels or variables based on an “effective value” analysis.
[0044] FIG. 21 schematically illustrates a method AF500 to identify “Notables” that is, alarms that appear in the high ranks in more than one list of alarms (ranked based on their different risk characteristics).
[0045] FIG. 22 presents a chart showing exemplary alarms with highest STAR ratings, whereby the Notable Alarms are arranged according to the STAR rating of each alarm.
[0046] FIG. 23 presents a bar graph showing an exemplary rank variation chart to compare and assess the changes in the ranks of alarms and/or variables.
[0047] FIG. 24 presents a line graph showing the same data as FIG. 23 , but in a different format to show “maximum change” in an exemplary rank variation chart to compare and assess the changes in the ranks of alarms and/or variables. X-axis shows absolute change, y-axis shows the variable/alarm.
[0048] FIG. 25 schematically illustrates the Dynamic Risk Analyzer system (DRA) and its three components, denoted by 1) a Prominent Transitions Analysis (DRA100), including a subset Grading and Ranking of Transitions and Prominent Transitions for Discrete Sigma Levels; 2) a Dynamic Risk Index (DRA200); and 3) a Compounded Risk Score (DRA300).
[0049] FIG. 26 schematically illustrates grading and ranking transitions in a given time period.
[0050] FIG. 27 schematically illustrates a method for calculating a post probability value for a transition, the value being obtained using Bayesian statistics, with priors based on long-term averages.
[0051] FIG. 28 schematically illustrates a method DRA200 to calculate “Dynamic Risk Index (DRI)” of a plant/facility.
[0052] FIG. 29 schematically illustrates a method DRA300 to calculate “compounded risk score.”
[0053] FIG. 30 diagrammatically provides a line graph showing an exemplary Compounded Risk Score for Variable A over a period of 6 weeks.
[0054] FIG. 31 graphically provides a bar graph reiterating the data shown in FIG. 30 .
[0055] FIG. 32 schematically illustrates the Real-time Leading Signal Generator system (LI).
[0056] FIG. 33 schematically illustrates a method to generate “Real-time Leading Signals.”
[0057] FIG. 34 graphically depicts a Music Bar Chart, wherein the bars associated with the variables, such as exemplary variables PI-100 and TI-200. The bars are displayed as a stack.
[0058] FIG. 35 schematically illustrates the concept of a “Real-Time Risk Indicator” in method LI200 to assess and display how risk associated with various equipment and interlocks/ESDs in a plant/facility changing with time
[0059] FIG. 36 schematically illustrates the Near Miss Surfer system (NMS).
[0060] FIG. 37 graphically shows a pyramid in which the peak is the actual accidents that occur at a plant/facility, but a larger number of observed or observable incidents are near-misses that did not result in an adverse incident, but could have. However, beneath the observable near misses are a large number of previously hidden or unobservable process near-misses that provide information that was not previously known or recognized as predictive of operational risks, and these form the bottom or underlying supporting level of the pyramid.
[0061] FIG. 38 schematically illustrates a method NMS100 in the Near Miss Surfer to detect and classify “hidden process near-misses” automatically.
DETAILED DESCRIPTION OF THE INVENTION
[0062] The Dynamic Risk Predictor Suite (DRPS) system comprises at least four subsystems, designed to be utilized individually or jointly, the details of which follow. The Subsystems are:
(1) Alarm Fitness (AF), (2) Dynamic Risk Analyzer (DRA), (3) Real-time Leading Signal Generator (LSG), and (4) Near-Miss Surfer (NMS).
[0067] I. The Alarm Fitness Subsystem
[0068] Alarm Fitness system (AF) is designed to exploit most “raw alarm data” recorded by “distributed control system” (DCS) and “emergency shutdown” (ESD) database systems, and converted to a knowledge base on “risk-based alarm data analysis.” “Raw Alarm data” is related to the process data since alarms are based on set values of process variables (also termed “process parameters” in literature). Notably, each variable is equipped by an alarm if identified as an important variable. Only the variables that are thought to be very important, are not only measured, but are also controlled by the DCS and are equipped by one or more alarms. For example, a temperature variable would have H1, L1, H2 (higher than the preset H1), and L2 (lower than the preset L1) alarms, wherein the alarms are set so that they are activated when the variable reaches the identified value preset by the plant or facility using the alarms. As a result, in this example there would be four alarms associated with the temperature values. The actual value of the temperature would be part of “process data;” reported alarm activations and deactivations would be part of “alarm data.” Both activations and deactivations are recorded and reported by the DCS. Of course, not all process variables have four alarms. Some could have only one, whereas others could have 10 or more. Conversely, some less important ones may have none. The number of alarms depends on the process operation and the design of alarm system.
[0069] Some process variables are also equipped with “Emergency Shutdown Systems” (ESD). These systems activate an alarm informing the operator of the real-time extreme condition, and either sequentially or simultaneously tries to correct the situation by automatically causing a corrective action, and if that does not work, shutting down the system. Alternatively, the ESD may simply shut down the system without additional corrective action. Typically, ESD settings are higher than H2/L2 and H1/L1 alarm settings, however in some cases, they are identical with H2/L2 alarm settings.
[0070] FIG. 1 schematically illustrates the Alarm Fitness system AF and its components, denoted by Advanced Frequency Analysis (AF100), Finer Alarm Flood and Alarm Attack Analysis (AF200), Abnormal Event Analysis (AF300), Time Segment Analysis (AF400), and Notables Analysis (AF500). The components signify “advanced alarm data analysis” and transform “raw alarm data” to serve three purposes summarized below. The new methods bring significant improvements and new perspectives over existing/standard techniques and software on “alarm management.” The three purposes served by AF are:
(1) To provide risk information/rating/status as conveyed by the alarm system. For example, AF signals increased/decreased potential for problems that may be lurking, as indicated by the novel concepts defined below (e.g., significant reduction in kick-off times, significant increase in recovery times, etc.). (2) To help engineers and operators configure alarms on an ongoing basis, to improve the accuracy and significance of information the alarms provide. (3) To signal potential issues/problems with the alarm system.
[0074] Note that methods defined in Alarm Fitness system apply for those facilities and process variables as well which are not equipped with alarms. In these cases, for any variable, alarms can be set at predetermined limits and “raw alarm data” can be obtained from process data when the variable crosses the set limits.
[0075] I.A. The Advanced Frequency Analysis:
[0076] The “Advanced Frequency Analysis,” component AF100 of the Alarm Fitness system, comprises: (a) developing a “classified chart,” which refers to a chart with banded zones indicating different significance levels, (b) identifying or classifying frequency bands for meaningful interpretation, and c) analyzing the data within a given zone as well as between the zones, for one or more time periods.
[0077] I.A.1. Classified Charting: Method AF101 (see FIG. 2 ) provides “classified charts” indicating zones of varying significance utilizing steps AF101a thru AF101e as described. First step, AF101a, provides receiving “frequency data,” also known as “training data” when it is gathered during a “training period.” The “training data” is defined as any set of representative data collected over a long period of time (long-term) to provide typical and characteristic information to be used in calculations in consideration; training data is collected within a time frame that ranges between 30 to 365 days—typically 60 days. Thus, the time frame during which the training data is collected is referred as the “training period.” Second step, AF101b, specifies the number of zones, n zone , in classified charts. For example, FIG. 3 shows a “classified chart” with three zones (n zone =3) signifying extreme, moderate and normal intensity/severity of frequency values. These three zones are identified using “frequency bands”—normal, moderate and extreme frequency zones, as shown. Third step, AF101c, sets the boundaries of these zones using “training data.” For example, for FIG. 3 , the boundary between the normal and the moderate bands (referred to as “boundary 1”) is set anywhere between 60th and 80th percentile based on the training data. A typical value is 75th percentile. Each boundary is updated periodically as more training data becomes available. If a fixed boundary is desired, a target value is specified by the operations. The boundary between the moderate and the extreme bands (referred as “boundary 2”) is set as a function of the difference between Boundary 1 and another percentile, for example at 75th Percentile+μ*(75th % ile-25% ile). Typically, μ ranges from 1 to 3. Fourth step, AF101d, categorizes data points in a training period in the identified zones. Fifth step, AF101e, updates both the training data and boundaries periodically—typically updates are daily.
[0078] The frequency data received in AF101a can include “raw alarm data,” “raw abnormal events data,” “time segment related data,” and the like. “Raw abnormal events data,” refers to data on “abnormal events” for different variables for a given time period, as will be described in greater detail below. “Time segment related data” refers to data on “time segment” calculations (such as values of “acceleration time,” “deceleration time,” “kick-off time,” “neighborhood time”) for different variables for a given time period, as described in greater detail below.
[0079] As applied to “raw alarm data.” there are “Alarm Frequency Charts” (AFCs), the use of which is known in the art. Typically, 10-min, 1-hour, daily, and weekly alarm frequency charts are used in alarm tracking/management practice. “Classified alarm frequency charts” (CAFCs) are prepared for different frequencies of alarms, e.g., 1-min, 10-min, hourly, daily, weekly, biweekly, monthly, quarterly, and the like as needed, and as indicated, the boundaries are updated periodically. In addition, the charts are prepared for “raw alarm data” associated with the entire process operation or for a select group of alarms.
[0080] As an example, FIG. 3 shows a classified alarm frequency chart, which presents frequency of alarms per day for a period of 7 months. In FIG. 3 , the 75th and 25th percentiles are equal to 234 and 44. Consequently, using the 7-month data as training period, the thresholds for the normal and moderate bands, or for the moderate and extreme bands, are calculated as 234 (equal to 75th percentile) and 519 (equal to 75th percentile+μ*(75th percentile−25% percentile) with μ=1.5). Using this data, out of a total of 214 data points, 160 data points are within the normal band zone, 24 data points are in the moderate band zone, and 30 points are in the extreme band zone.
[0081] Thus, an important utility of the classified charts, including classified alarm frequency charts, is that they quantify the proportion of data points in each zone including the extreme data points (e.g., in above example, 14% of the data points lie in the extreme band zone), which helps plant/facility personnel to understand quantitatively the proportion of important data points (“attention points”), so that the operators and plant/facility personnel can focus on addressing and reducing occurrence of data points in the extreme zone.
[0082] Another utility of these charts is to permit plant/facility personnel to compare the performance of an alarm system over different time periods. For example, a comparison of monthly frequency (and/or percentage) of extreme data points informs the plant/facility personnel about the months that are seen to have more days of extreme alarm frequency. Further, these charts enable quantitative comparison of alarm frequencies for different equipment/units for different time periods. In other words, the proportions of data points in the displayed zones or bands serve as a standardized tool or criterion to compare different frequency charts for (a) different equipment/units, as well as (b) for different time periods. This is important because presently, frequency charts present data points without designating bands or zones; and as a result the prior art offers no mechanism for direct identification of data points that that are of particular relevance, such as the 30 points (out of 210) which were in the “extreme frequency zone.” Although certainly points in the extreme zone deserve the most attention from plant/facility personnel, in a prior art frequency chart (without any zones or bands), it is not easy to identify or pinpoint these “extreme” data points (or simply “outliers”) directly, meaning that the significance of those points may be missed. This disadvantage in the prior art is overcome by the presently disclosed methods, using charts and lists, to permit plant/facility personnel to now recognize signals of extreme occurrence before problems arise or accidents occur.
[0083] I.B. Alarm Flood and Alarm Attack Analysis:
[0084] The “Finer Alarm Flood and Alarm Attack Analysis,” component AF200 of the Alarm Fitness system, comprises: at least the two identified parts regarding the Finer Flood Analysis and the Alarm Attack Analysis, each having specific elements as set forth in FIGS. 4 and 5 , respectively. But stepping back, historically “standing alarms” refer to those alarms which are active at any time. The concept of a “standard alarm flood” analysis is known in the art and has been in practice for several years. According to its definition by EEMUA (Engineering Equipment & Materials Users' Assoc.), an “alarm flood” is defined as beginning when 10 or more alarms occur in a 10 minute period, and ending when less than 5 alarms occur in a 10-minute period. The “Finer Flood Analysis” (FFA) method, AF201 (illustrated in FIG. 4 ), performs an accurate analysis of alarm flood conditions (which refer to conditions when several alarms are generated or flood in a short period of time).
[0085] I.B.1 Finer Flood Analysis: Accordingly, for the AF201 analysis, an alarm “flood” begins when at least X 1 alarm activations occur in less than (or equal to) Y 1 minutes (see step AF201b of FIG. 4 ); and the flood ends when X 2 alarms occur in more than Y 2 minutes (see step AF201c of FIG. 4 ). Here, the values of X 1 , X 2 and Y 1 , Y 2 are integers chosen between [5, 20]. Typical examples used in operations are X 1 =10, X 2 =5 activations, and Y 1 =10 minutes, Y 2 =10 minutes.
[0086] Typically during alarm floods, plant/facility operators get less than 1 minute to attend to an alarm (based on the above definition). When important alarms occur during these periods, there is an increased likelihood that the operators might miss those alarms, or fail to pay attention to one specific alarm. Consequently, the potential for the occurrence of adverse incidents typically increases during alarm flood conditions.
[0087] For example, an illustrative comparison is provided to show the results of a Standard Alarm Flood analysis (prior art), as compared with the results using the AF201 methods for a period of 3.5 months for an typical industrial plant:
[0000]
Standard Alarm Flood Analysis
Finer Flood Analysis
Number of floods = 66
Number of floods = 124
Mean time of flood = 20.7576
Mean time of flood = 26 min
min
Mean inter-arrival for floods
Mean inter-arrival time for
(hrs) = 32.83
floods (hrs) = 17.63
Longest flood = 100 min
Longest flood = 237 min
% of major floods (# alarms >
% of major floods (# alarms >
30) = 18.18
30) = 18.5
Avg. number of alarms in flood =
Avg. number of alarms in flood =
27.3939
25
Total number of alarms in floods =
Total number of alarms in floods =
1808
3093
Percent of alarms in floods = 5.5761
Percent of alarms in floods = 9.5
% of time alarm system in flood
% of time alarm system in flood
condition = 1.0276
condition = 2.4
[0088] Note that EEMUA recommends that the percent of time an alarm system is in flood condition should be less than 1%. It is observed that in the standard prior art alarm flood analyses, in most cases, the number and impact of alarm floods is under-estimated in a given system. Nevertheless, in the above example, the AF201 analysis detected 87.9% more alarm floods in the study period of 3.5 months, as compared to that of standard alarm flood analysis. Also, the percent of time alarm system was in flood condition during the study period estimated by the AF201 analysis was nearly 2.4 times that of the standard alarm flood analysis, reflecting the fact that the actual alarm flood conditions occurred both more frequently, as well as for longer periods of time, than what was identified by the standard alarm flood analysis. This also means that in reality, the plant/facility operators were busier trying to correct the alarm situations, than what was identified by the standard alarm flood analysis.
[0089] In fact, an accurate analysis of alarm flood conditions is important for a variety of other reasons. Typically, the manpower in a control room (mainly control panel operators) is adjusted according to the expected alarm frequency load in a shift. If the alarm flood conditions are under-estimated, the plant/facility's manpower is respectively likely to be insufficient, which would increase the potential occurrence of adverse incidents. Moreover, the time periods with a high frequency of alarms, relevant to acceptable alarm levels of the plant or facility operation, need to be identified accurately so that the devices controlling the alarms are tuned to the right settings.
[0090] Thus, a utility of the AF201 analysis in FIG. 4 is that the analysis helps detect alarm floods which cannot be detected by standard alarm flood analyses. More specifically, as compared to such standard alarm flood analysis as are available in the prior art, in most cases, (a) the AF201 analysis detects a higher percentage and number of alarm floods in a given time period, (b) most floods detected by the AF201 analysis last longer than the comparable findings, and (c) the AF201 analysis found that the floods happen more frequently than were previously expected. This analysis applies to any group of alarms, ranging from total alarms in a given unit/plant or facility to a select group of alarms.
[0091] Notably the standard prior art flood analysis depends totally on the starting point of the 10-min interval. In other words, based on the time at which the 10-min period starts (e.g. on the hour, or 1-min past the hour), different results are obtained.
[0092] I.B.1.a. Advanced Grading and Ranking of Alarm Floods: A method AF202 is illustrated in FIG. 5 to grade and rank the alarm floods in a given time period (e.g., days, weeks, months, custom time period), also referred as “test period.” The grading and ranking of alarm floods help plant/facility personnel prioritize the alarm floods, so that operators can focus and address the alarms that contributed the most to the occurrence of the important alarm floods. These criteria are used individually or in any combination. Also, this analysis applies to all the alarms or a subset of alarms.
[0093] Step AF202c consists at least of evaluation of the following four criteria for each alarm flood:
[0094] 1. Duration of alarm flood: The longer the duration, the more critical alarm flood is to the system.
[0095] 2. Weighted alarms per minute: In most plants/facilities, alarms are prioritized by plant/facility personnel during the commissioning of the plant or facility. This process is intended to help the operators address the more important alarms first during any urgent situation. Because there are often hundreds of alarms for a given process in the plant/facility, the alarms are typically prioritized into three categories—high-priority, medium-priority, and low-priority. The categorization determination into at least 2 or more groupings, is done by the plant/facility owners or operators. The categorization is set forth in the data that is provided to the current analyses. The invention does not prioritize the alarms, nor does the invention control or name the categories of alarms selected by the plant/facility owners or operators in association with the alarm priority of response; rather that is reflected in the alarm data that is provided.
[0096] Typically, the top 5-10% most important alarms relative to plant/facility operation are referred as “high-priority.” The next 20-30% of the alarms is typically designated by the plant/facility to be of “medium-priority,” and the remaining are considered by the plant/facility to be “low-priority” alarms. Conversely, if for a particular plant/facility, no priorities have been defined for the alarms, in the present calculations all alarms are treated equally. However, when the alarms have be divided into predetermined categories, such as high, medium and low, weighting factors are introduced for different categories of alarms, e.g., weighted alarms/min=w1*(High-priority alarms/min)+w2*(Medium-priority alarms/min)+w3*(Low-priority alarms/min), where, w1, w2, and w3 are the weighting factors. Weighted alarms/min equals Total alarms/min. Typical values are w1:w2:w3=5:3:1. And as a result, the higher the number of weighted alarms per minute for an alarm flood, the more critical each alarm is in the system.
[0097] 3. Share of significant alarms: This criterion is based on percentage of significant alarms in a flood, i.e., 100*(Total significant alarms)/(Total alarms). “Significant alarms” are predetermined by the plant/facility owners or operators based upon the operations. However, significant alarms to a particular operation typically consist of all of or a select percentage of the high-priority and medium-priority alarms.
[0098] 4. “Alarm Flood Intensity” or Average number of “fresh standing alarms” at any time: “Fresh standing alarms” are defined as those alarms, which are active for less than 24 hours, or alternatively as for any fixed time period between 3 hrs and 48 hrs. This is an important measure for understanding the intensity of “fresh standing alarms” in an alarm flood, and is used to compare the criticality/importance of different alarm floods. This fourth criterion is based on average number of “fresh standing alarms” at any time during the alarm flood. The higher the alarm flood intensity for an alarm flood, the more critical each is to the system.
[0099] Calculation steps for “Alarm Flood Intensity”: For the duration of an alarm flood, the numbers of “fresh standing alarms” at select time intervals are obtained. Next, their average over the alarm flood period is calculated by summing the numbers of “fresh standing alarms” at select time intervals and dividing the sum by the total number of time intervals during the alarm flood. This value provides the “alarm flood intensity” for the alarm flood in consideration. The smaller the select time interval is, the more accurate the alarm flood intensity value becomes. For example, consider an alarm flood that lasts 10 minutes or 600 seconds. First, the numbers of “fresh standing alarms” at every second during the 10-min period are obtained from the alarm data. Second, these numbers are added to obtain the ‘total.’ Finally, the ‘total’ is divided by 600 (total number of time intervals during the alarm flood) to obtain the alarm flood intensity for this flood.
[0100] I.B.1.b. Determining Criticality Levels for Alarm Floods on an Absolute Scale (Step AF202d): Using the above four criteria, various criticality levels can be defined to characterize the alarm floods on an absolute scale. Herein, the following three criticality levels are recommended: ‘Δ 3 ,’ ‘Δ 2 ,’ and ‘Δ 1 .’ See definitions below.
[0101] Method of Calculation for Criticality Levels: First, a training period is selected, and alarm floods in that period are identified. The recommended range for a training period is 1 month to 2 years, typically 6 months. Next, for each of the alarm floods, the above-identified four criteria are calculated. Then, for each of the four criteria, different percentile levels (e.g., 25th, 50th, 60th, 70th, 75th, 90th, etc.) are determined from the values for all the alarm floods during the training period.
[0102] The following are the steps in determining a criticality level for an alarm flood (in test period).
Classify a flood as Δ 3 , if the value of each criterion associated with that flood is above X 3 th percentile of the values for that criterion calculated using the training period (as explained above). Here, the value of X 3 ranges between [50, 100)—typical value is 75. Classify a flood as Δ 3 , if the value of any criterion associated with that flood is above X 4 th percentile of the values for that criterion calculated using the training period. Here, the value of X 4 ranges between [X 3 +10, 100)—typical value is 90. Classify the remaining floods as Δ 1 alarm floods.
[0106] Relative Ranking of Alarm Floods within a Given Criticality Level (Step AF202e): The following describes the steps to determine the relative ranks of alarm floods within a given criticality level (for example, Δ 3 , Δ 2 , or Δ 1 ) as defined above. First, list all alarm floods for a given criticality level. Then, prepare a list of floods in a decreasing order for each of the four criteria. The floods are ordered in decreasing order of their values determined per criterion calculations described above. Then assign ranks to the floods in each list, ranking the top, meaning the most critical alarm flood, as #1. Finally, to determine the relative ranking of floods within a given criticality category, a) obtain the final rank of each alarm flood by adding the four individual ranks, and b) organize the final list in ascending order.
[0107] I.B.2. Alarm Attack Analysis:
[0108] A method AF203 to calculate “alarm attacks” is illustrated in FIG. 6 . An “alarm attack” begins (step AF203b) when the number of “fresh standing alarms” at any time becomes ≧X 5 and ends (step AF203c) when the number becomes ≦X 6 . Here, the values of X 5 and X 6 are integers chosen between [5, 20] with X 5 >X 6 . Typical examples are X 5 =10 and X 6 =8. This new method identifies the periods of high intensity alarm surges (or build-ups), which overwhelm the operators and possibly cause their ability to respond to the alarm situation to decline. The utility of method AF203 is that this analysis identifies periods and frequency of alarm surges (which indicate the periods of increased potential of occurrence of incidents) and helps the plant/facility personnel to adjust the manpower and controller settings properly and regularly.
[0109] FIG. 7 shows exemplary alarm attacks, finer floods and standard alarm floods for a period of 20 minutes. However, the figure also shows that the alarm floods and the alarm attacks have different utilities. The former identifies periods having a high rate of new alarm activations (which does not necessarily contribute to alarm build ups), while the latter identifies alarm build-ups.
[0110] Identifying alarm attacks and eliminating their occurrences is very critical to enabling the operators to focus on issues that are important to operation of the plant/facility, thereby improving the safety, productivity (operability), and quality. For example, consider an alarm attack that lasted for 15 minutes in a given day. Identifying and eliminating reoccurrence of the alarm will result in equivalent amount of productivity gained for the operators. Also, this method applies to all or select group of the alarms.
[0111] I.B.2.a. Grading and Ranking of Alarm Attacks: A method AF204 is illustrated in FIG. 8 to grade and rank the alarm attacks in a given time period (e.g., days, weeks, months, custom time period), also referred as test period. The grading and ranking of alarm attacks help the plant/facility personnel prioritize the alarm attacks, so that operators can focus and address the alarms that contributed the most to the important alarm attacks. These criteria are used individually or in any combination. As above, this analysis also applies to all the alarms or a subset of alarms.
[0112] Step AF204c of FIG. 8 consists of evaluating at least the following four criteria for each alarm flood:
1. Duration of alarm attack: The longer the duration, the more critical the alarm attack. 2. “Alarm Attack Intensity” or Average number of “fresh standing alarms” at any time: This is an important measure to understand the intensity of “fresh standing alarms” in an alarm attack and is used to compare the criticality/importance of different alarm attacks. This criterion is based on average number of “fresh standing alarms” at any time during the alarm attack. The higher the intensity for an alarm attack, the more critical the alarm(s) is to the operation of the plant/facility.
[0115] Calculation steps for “Alarm Attack Intensity”: For the duration of an alarm attack, the number(s) of “fresh standing alarms” at select time intervals are obtained. Next, their average over the alarm attack period is calculated by summing the numbers of “fresh standing alarms” at select time intervals and then dividing the sum by the total number of time intervals during the alarm attack. This value provides the “alarm attack intensity” for the alarm attack under examination. The smaller the select time interval is, the more accurate the alarm attack intensity value is in the analysis.
3. “Escalation rate”: Escalation rate defines how fast the alarm attack flourishes. Following are the steps for calculating the escalation rate of an alarm attack:
(a) Identify each of the X 5 “fresh standing alarms” that triggered the alarm attack. (b) For each of the X 5 “fresh standing alarms,” calculate the time distance from the starting point of the alarm attack, i.e. for each of the X 5 “fresh standing alarms,” and then using the activation time, calculate time distance from the start of the alarm attack. (c) Calculate the median value of all X 5 time distance values to obtain the “mathematical escalation rate” of the alarm attack (default case). (d) Or in the alternative, calculate the mean value of all X 5 time distance values.
[0121] Three levels of Escalation Rate are defined: Rapid (mathematical escalation rate ≦5 min), Moderate (mathematical escalation rate >5 min, but ≦15 min), and Gradual (mathematical escalation rate >15 min). For example, alarm attacks with ‘Rapid’ escalation rate indicate a fast build-up of alarms, indicating either progression of a disturbance or an inability of controller to resolve a process issue. In both cases, the disturbance is an adverse event requiring fast action/response by the operators, and indicating a sudden increase in the potential increased occurrence of incidents. Thus, identifying alarm attacks and eliminating their occurrences is critical to plant/facility operations.
[0122] 4. “Fractional Intensity of significant alarms”: This criterion is based on fractional intensity of significant alarms in an alarm attack. “Fractional intensity” is defined as 100*Intensity (significant alarms)/Intensity (Total alarms), when Intensity (significant alarms) refers to average number of “fresh standing alarms,” calculated using significant alarms, at any time during the alarm attack. Intensity (Total alarms) refers to average number of “fresh standing alarms,” calculated using all the alarms, at any time during the alarm attack. As with previously identified categorization tools, “significant alarms” are identified by the plant/facility owner or operators, and are specific to the operations under examination. Significant alarms typically consist of all of or at least some high-priority and medium-priority alarms.
[0123] I.B.2.b. Determination of Critically Levels for Alarm Attacks on an Absolute Scale (Step AF204d): Using the above four criteria, various criticality levels are defined to characterize the alarm attacks on an absolute scale. Here, as above, the following three criticality levels are recommended: ‘Δ 3 ’, ‘Δ 2 ’, and ‘Δ 1 ’ as previously defined.
[0124] Calculation Steps for Criticality Levels: As previously described for other calculations, first, a training period is selected and alarm attacks in that period are identified. The recommended range for training period is 1 month to 2 years, typically 6 months. Next, for each of the alarm attacks, the four criteria defined above are calculated. Then, for the three criteria—duration of alarm attack, alarm attack intensity, and fractional intensity of significant alarms—different percentile levels (25th, 50th, 60th, 70th, 75th, 90th, etc.) are determined by utilizing values for all the alarm attacks during the training period.
[0125] The following steps are set forth for determining a criticality level for an alarm attack (in test period).
Classify an attack as Δ 3 , (a) if the value of each of the three criteria (duration of alarm attack, alarm attack intensity, and fractional intensity of significant alarms) is above the X 7 th percentile of the values for that criterion calculated using the training data, AND (b) if its Escalation Rate is ‘Rapid.’ Here, the value of X 7 ranges between [50, 100)—typical value is 75. Classify an attack as Δ 2 , (a) if the value of any of three criteria (duration of alarm attack, alarm attack intensity, and fractional intensity of significant alarms) is above X 8 th percentile of the values for that criterion calculated using the training data, or (b) if the alarm attack Escalation Rate is ‘Rapid.’ Here, the value of X 8 ranges between [X7+10, 100)—typical value is 90. Classify the remaining attacks as Δ 1 alarm attacks.
[0129] I.B.2.c. Relative Ranking of Alarm Attacks within a Given Criticality Level (Step AF204e): The following describes the steps to determine the relative ranks of alarm attacks within a given criticality level (for example, ‘Δ 3 ’, ‘Δ 2 ’, or ‘Δ 1 ’) as defined above. First, list all the alarm attacks for a given criticality level. Then, prepare a list of attacks in a decreasing order for each of the four above identified criteria used for attack floods. The attacks are ordered in decreasing order of their values determined per criterion calculations described above. Note that for ‘Escalation rate’ criterion, when categories for two or more alarm attacks are the same, equal ranks are assigned. Next, assign ranks to the attacks in each list, ranking the top (most critical to operations) one as #1. Finally, to determine the relative ranking of attacks within a given criticality category: a) obtain the final rank of each alarm attack by adding the four individual ranks, and b) organize the final list in ascending order.
[0130] I.C. Abnormal Events Analysis:
[0131] In a plant/facility, the alarms are prioritized into different categories (e.g. high, medium, low) by the owners and operators who best understand their operations, to assist the operators with their decisions to prioritize their actions during upset or adverse event situations. Further, each alarm is associated with a specific alarm level, e.g., first level alarms include ‘H1’ and ‘L1’ alarms, second level of alarms include ‘H2’ (higher than the preset ‘H1’) and ‘L2’ (lower than the preset L1) alarms, etc, as previously described in the temperature setting of the Alarm Fitness Subsystem section, wherein the alarms are set so that they are activated when the variable reaches the identified value preset by the plant or facility using the alarms.
[0132] Definition and calculation of an abnormal event: The concept of an “abnormal event” or problem is known (see, Pariyani et al., supra, 2010a and 2010b; Pariyani, et al., AIChE J. 58(3):812-825 (2012a); Pariyani et al., AIChE J. 58(3): 826-841 (2012b)). An abnormal event begins (step AF301b) when a variable moves beyond a normal operating range (defined as the region within the predetermined high and low alarms), and ends when the variable returns to within the normal operating range between the alarm settings. Therefore, when an abnormal event happens, one or more alarms are triggered.
[0133] Usually, the challenge for a plant/facility operator is to analyze the one or more abnormal events (in real-time as well as periodically) and to take actions to prevent their reoccurrence. But since there are often numerous abnormal events that happen during plant/facility operations, one needs to prioritize the occurrence of the abnormal event(s), so that the most significant event(s) can be addressed first. Depending upon the highest level of alarm(s) associated with the abnormal event, three criticalities have been defined in the literature (Pariyani et al., supra, 2010a and 2010b; Pariyani et al., supra 2012a and 2012b), as follows: (a) “least-critical abnormal events” that cross the H1/L1 alarm thresholds, (b) moderately-critical abnormal events that cross H2/L2 alarm thresholds, and (c) most-critical abnormal events that cross the ESD thresholds. However, these definitions of criticality take only the level of alarms into account. The definitions do not take into account the priority of alarms.
[0134] For example, consider an abnormal event that crosses a H1 alarm level associated with Variable A, and assume that the priority of this H1 alarm level is LOW. Also consider another abnormal event that crosses a H1 alarm level associated with Variable B, and assume that the priority of this H1 level is HIGH. According to preceding definition, both the abnormal events are thus referred as “least-critical abnormal events.” However, their actual criticalities with respect to the process are not the same—in fact, the latter is much more critical than the former. This shortcoming is addressed by the present method of determining “scale of abnormal events” as follows.
[0135] I.C.1. Scale Determination of an Abnormal Event and Formulation of Abnormal Events Matrix: First, for each abnormal event, a method AF301 to determine “scale” of an abnormal event and to formulate “abnormal events matrix” is presented in FIG. 9 . The “scale” of an abnormal event (step AF301c) is defined by its two components: (a) Stage of the abnormal event; and (b) Criticality of the abnormal event. “Stage” of an abnormal event is defined by level of the “outermost alarm,” activated during the abnormal event. An “outermost alarm” refers to the highest alarm level crossed by a variable during an abnormal event. For example, consider FIG. 12 , in which like sound waves progressing outward from the source, the variable crosses both its H1 and H2 alarm levels during an abnormal event. In that situation, the outermost alarm is its H2 alarm. If the variable had only crossed its H1 alarm, then its outermost alarm would only be the H1 alarm. “Criticality” of an abnormal event is defined by priority of the outermost alarm that is activated during the abnormal event.
[0136] In accordance with step AF301d, in FIG. 9 , the columns of “Abnormal Events Matrix” are the different possible levels of outermost alarm (activated during the abnormal events). The rows of the FIG. 10 matrix represent the different possible priorities of the outermost alarm (as activated during the abnormal events). Therefore, the cells of this matrix indicate the different scales of abnormal events.
[0137] The concept of the Abnormal Events Matrix extends the earlier categorization of abnormal events (based on ‘levels of alarms’) to include the second dimension of the ‘priority of alarms’ (assigned by plant/facility personnel based on the characteristics of variables with which the alarms are associated). The matrix helps prioritize the different kinds of abnormal events, so that the most significant alarm events can be addressed first.
[0138] The number of columns and rows of the matrix are determined by the characteristics of the alarm system. Accordingly, the following specific example is provided to demonstrate the Abnormal Events Matrix method.
[0139] A 3×4 Abnormal Events matrix is constructed (as shown in FIG. 10 ), representing the previously identified 4 levels of alarms as columns, and in this case, 3 priorities of alarms (“High,” “Medium,” and “Low”) are the rows. Consequently, 12 scales of abnormal Alarm events are defined and represented by the 12 cells of the matrix. The top row (all cells) indicates the “most-critical abnormal events” (of all stages), middle row (all cells) indicates the “moderately-critical abnormal events” (of all stages), and bottom row (all cells) indicates the “least-critical abnormal events” (of all stages). The left column (all cells) indicates the 1st stage abnormal events (of all criticalities); the column 2nd from left (all cells) indicates the 2nd stage abnormal events (of all criticalities); the column 3rd from left (all cells) indicates the 3rd stage abnormal events (of all criticalities); and the column 4th from left (all cells) indicates the 4th stage abnormal events (of all criticalities). Thus, within a row, the ‘scale’ of abnormal events increases from left to right; whereas within a column, the ‘scale’ of abnormal events increases from bottom to top. See, FIG. 10 .
[0140] As discussed above in the subsection relating to “classified charts,” “abnormal events charts,” as in FIG. 3 are prepared to display the frequency of abnormal events (of any scale) over a given time period. These abnormal events charts are prepared for frequencies in different time intervals (1-min, 10-min, hourly, daily, weekly, biweekly, monthly, etc.) and for all the variables as well as select group of variables. Thresholds are calculated for at least a “Normal Operations Zone” (or band), a “Moderate Frequency Zone” (or band), and an “Extreme Frequency Zone” (or band). The threshold boundaries, as defined above in the Classified Charting, between the Normal Operations Zone and the Moderate Frequency Zone, and between the Moderate Frequency Zone and the Extreme Frequency Zone, for classified abnormal event frequency charts are obtained using the formulas presented above.
[0141] Organization of Variables Based on Scales of Abnormal Events: For each cell in the matrix, lists of variables are prepared based on different criteria such as frequency of abnormal events, time segment, combinations of criteria, etc. These lists are prepared for all the variables, or for a select group of variables, for different time intervals (days, weeks, months, etc.).
[0142] Definition of Ultimate Abnormal Events: If any variable crosses its ESD level, without resulting in a shutdown, the associated abnormal event is defined as an “ultimate abnormal event.” In the example presented above in association with FIG. 10 , the 4th stage most-critical abnormal events are also ultimate abnormal events. It is important for plant/facility personnel to minimize the occurrence of ultimate abnormal events, as the events are precursors to shutdowns or adverse incidents at the plant/facility. Tracking ultimate abnormal events for different time periods helps compare the safety performance of a given unit from one time period to another.
[0143] I.C.2. Identification of Riskiest Abnormal Events: A method AF302 to identify the riskiest abnormal events in a given time period (shift, daily, weekly, monthly) is schematically illustrated in FIG. 11 . This is used to identify (a) riskiest abnormal events for a given variable, within a time period, and/or (b) riskiest abnormal events for a group of variables, within a time period. This helps the plant/facility personnel to prioritize the abnormal events and focus first on the ones that are most important to safety or operation.
[0144] For each abnormal event, a “risk score” (step AF302c) is defined as a function of its characteristics, such as time spent beyond its alarm levels, highest value attained by the variable during the abnormal event, etc. For example, for a 2nd stage abnormal event shown in FIG. 12 , a recommended form of risk score is w 1 *t 1 +w 2 *t 2 , where t 1 and t 2 denote times spent beyond 1 st and 2 nd alarm levels, and w 1 and w 2 refer to weighting factors indicating the relative importance of the times. Their typical values are 10 and 1. A higher value “risk score” indicates a riskier abnormal event; “risk” assumes its normal meaning as relevant to one or more liabilities to the safety of the plant/facility operators or to others, or to the effectiveness and efficiency of operation(s). Note that for two abnormal events for which values of t 2 are equal, the one which has higher value of t 1 is riskier. On the other hand, when values of t 1 are equal and t 2 are unequal, the value having a higher t 2 also carries the higher risk.
[0145] Also, note that when a group of variables is considered, weighting factors are assigned among the risk scores—with higher values for important variables. Then, a list of abnormal events in decreasing order of their risk scores is prepared to identify the riskiest abnormal events in a given time period (see step AF302d of FIG. 11 ).
[0146] For higher stage abnormal events like 3 rd stage and 4 th stage abnormal events, a sum of the recovery times associated with outer two or more alarm levels (“outer” being in terms of rank shown in FIG. 12 ) is used as “risk score,” e.g., consider an abnormal event which has crossed H1/L1, H2/L2, and H3/L3 alarms (if such addition levels were designated) and has spent t 1 , t 2 , and t 3 times, respectively (note than an additional level t 3 is assumed for time in this example as compared to FIG. 12 ). The risk score for the exemplified abnormal event is calculated as w 3 *t 3 +w 2 *t 2 or w 3 *t 3 +w 2 *t 2 +w 1 *t 1 . In the alternative, the risk score is calculated using other selected combinations/functional relationships of t 1 , t 2 , and t 3 (functional relationship containing any two or more of the times involved).
[0147] For example see also FIG. 13 , wherein t 2 is shown as the sum of m 1 and m 2 . In the case of the score presented in FIG. 13 , there are two peaks above the H2 alarm level. Total time (“t 2 ”) above the H2 alarm level, equals m 1 +m 2 , wherein m 1 is time spent by variable above the H2 alarm level during its first peak, and m 2 is time spent by variable above the H2 alarm level during its second peak. The term t 2 is used in the risk score calculations.
[0148] This method permits grading of different variables based on the abnormal events within a particular time period. For example, if there were 200 variables in a plant/facility, and over a period of last 6 months, each of them experienced hundreds of abnormal events, it would be advantageous if those variables could be graded. To do so, the AF303 method takes into account all the abnormal events, and calculates an overall “combined risk score” by combining the individual risk scores for each abnormal event, and then prepares a list of variables by arranging them in descending order by way of their “combined risk scores.”
[0149] I.C.3. Grading of Variables Based on Riskiest Abnormal Events: A method AF303 is illustrated in FIG. 14 to determine a “combined risk score” for one or more variables by combining the individual risk scores for each different type of abnormal event (2nd stage, 3rd stage abnormal events, etc., as stages are seen and described with regard to FIG. 10 ). The combination is accomplished using multiplication, or addition, or by other formulations, although typically, addition is used. Then, lists of variables are prepared based upon decreasing Combined Risk Score for a given time period.
[0150] I.D. Time Segment Analysis
[0151] Various time segment analyses are conducted based on the times, when an alarm is activated, and when it inactivates or is deactivated. Commonly used calculations are:
Recovery time: Time between an alarm activation and its subsequent inactivation or deactivation, wherein the time is defined for each alarm level. Inter-arrival time: Time between consecutive alarm activations at each alarm level. This term is also referred to as “time between alarms” or “distance between alarms.”
[0154] The time-segment analysis methods, as used alone or in any combination, either with each other, or in combination with previously known methods, are schematically shown in FIG. 19 .
[0155] I.D.1. “Kickoff time” analysis: “Kick-off time” is defined as the time elapsed from the last inactivation of an alarm to its next activation. It is defined for each alarm level. A method AF401 to identify the riskiest alarm levels based on kick-off time analysis is illustrated in FIG. 15 .
[0156] I.D.2. “Acceleration time” analysis: “Acceleration time” is the time difference between alarm activations of two consecutive alarm levels that belong to the same variable. Thus, for a variable having 3 layers of alarms (ranging from H1 to L1, from H2 to L2, and from H3 to L3), four sets of acceleration times are defined—for H1 to H2, L1 to L2, H2 to H3, and L2 to L3. A method AF402 to identify the riskiest consecutive pair of alarm levels based on acceleration time analysis is illustrated in FIG. 16 .
[0157] I.D.3. “Deceleration time” analysis: “Deceleration time” is the reverse of acceleration time, that is, “deceleration time” is the time difference between inactivations or deactivations of two consecutive alarm levels that belong to the same variable. Thus, for a variable having 3 layers of alarms (ranging from H1 to L1, from H2 to L2, and from H3 to L3), four sets of deceleration times are defined—for H3 to H2, L3 to L2, H2 to H1, and L2 to L1. A method AF403 to identify the riskiest consecutive pair of alarm levels based on deceleration time analysis is illustrated in FIG. 17 .
[0158] I.D.4. “Neighborhood time” analysis: “Neighborhood time” is the total time the value of a variable in close proximity of a referenced value. For alarm data analysis, reference value is typically taken as the alarm(s) set value for the given variable. The range of proximity is (0, ±20]% of the alarm set value referred to as “close proximity,” is also considered to be the “neighborhood” of the alarm value. Typically the value is ±5% of the referenced value. Thus, “neighborhood time” is defined for each alarm level associated with a given variable. A method AF404 to identify the riskiest variables based on “neighborhood time” analysis is illustrated in FIG. 18 .
[0159] While FIG. 19 graphically depicts the time segments and relationships discussed above, it can be seen that the above-mentioned time segments signify different characteristics of alarms and variables. The utility of the time segment methods is that they identify the important alarms and variables that need to be rapidly addressed by the plant/facility maintenance.
[0160] I.D.5. “Effective Value” analysis: The “effective value” of an entity is its current value modified to account for its relative increase or decrease with respect to its long-term moving average. “Effective value” of an entity is defined as (Actual Value of Entity)*(Relative Change), where, Relative Change=
[0000]
α
Actual
value
of
entity
Long
-
term
moving
average
of
entity
[
Equation
1
]
[0161] In this calculation a is a proportionality constant, anywhere between (0, 2]—typically equal to 1.
[0162] For a given time period, the following variations of effective values are defined when, n lies in [0, 100] —typical value being 90. Average value is written “avg” for simplicity; median is written “med.”
[0000]
Effective
avg
value
of
entity
=
(
Actual
avg
value
)
*
α
Actual
average
value
of
entity
Long
-
term
moving
average
of
entity
[
Equation
2
]
Effective
med
value
of
entity
=
(
Actual
med
value
)
*
α
Actual
median
value
of
entity
Long
-
term
moving
average
of
entity
[
Equation
3
]
Effective
n
th
%
ile
of
e
ntity
=
(
Actual
n
th
%
ile
)
*
α
Actual
n
th
percentile
value
of
entity
Long
-
term
moving
average
of
entity
[
Equation
4
]
[0163] For alarm data analysis, a method AF405 to identify the riskiest alarm levels or variables based on “effective value” analysis is illustrated in FIG. 20 . By using “effective time segments” as the ordering/arranging criteria, the alarms or variables that deviate most from their normal operations are identified, permitting identification of the riskiest alarm and variables based on that characteristic. An “effective time segment” is defined as a product of actual value of time segment and the associated relative change, which is proportional to the actual value of the time segment divided by its long-term moving average value. “Long-term moving average” is a known term used in literature, and is typically defined for sequence of data, recorded with a certain frequency. For the above-identified time segments, the “effective time segments” can be obtained using the above equations.
[0164] Effective Risk Score of an Abnormal Event: Based on the concept of “effective value,” the “effective risk score” of an abnormal event is defined as a product of actual risk score (of the abnormal event)*the associated relative change, which is proportional to actual risk score divided by its long-term moving average value.
[0165] Effective Number of Chattering Events: In literature, when three or more alarm activations occur in 1 minute, the alarm system is said to be in chattering mode (classic definition). The associated alarms and events are referred as “chattering alarms” and “chattering events,” respectively. Based on the concept of “effective value,” the “effective number of chattering events” in a time period is defined as the product of actual number of chattering events (in the time period) and the associated relative change, which is proportional to actual value of chattering events divided by its long-term moving average value.
[0166] I.E. Notables Analysis: “Notables” refer to noteworthy alarms, which appear in the higher ranks in more than one list of alarms (ranked based on their different risk characteristics). A method AF500 to identify the “Notables” is illustrated in FIG. 21 . The list of “Notables” is prepared periodically (after every shift, day, week, month, quarter, etc.). Further, notables may be prepared for all alarms, as well as for selected smaller groups of alarms. For example, for identifying ‘Notables,’ one or more of the following lists are selected:
(a) List of top M alarms based on total recovery time; (b) List of top M alarms based on average recovery time; (c) List of top M alarms based on frequency of alarms; (d) List of top M alarms based on average inter-arrival time; (e) List of top M alarms based on average neighborhood time; (f) List of top M alarms based on average kick-off time, wherein M varies between 5 to 20—with the typical value being 10.
[0173] Next, for each unique alarm (in the selected group of lists), the number of occurrences in different lists are counted. While coalescing the alarms from the different lists, each list is given a weighting factor, for example, 1:2:1:2:1:0, and the like. And finally, for each alarm, a STAR(*) rating is determined for each alarm as follows, in [Equation 5]:
[0000]
∑
=
i
=
1
n
(
weighting
factor
for
list
i
)
*
(
number
of
occurrences
of
that
alarm
in
list
i
)
[0000] The alarms with highest STAR ratings are identified as “Notables.” The list of Notables is then arranged according to the STAR ratings of the alarms as shown in FIG. 22 .
[0174] Dynamic Alarm Settings: In method AF601 to dynamically set first and second levels of alarms for a variable, the first level of alarms (step AF601a), that is, H1 and L1 alarms, are set at +/−3 sigma limits, determined using its online measurement values, collected at select time interval (1-sec, 2-sec, 5-sec, etc.), based on the rate of change of the value of the variable for a relatively long period of time (with respect to its variation in time). Fast changing variables are preferably sampled more frequently. The “long period of time” means that the time ranges from 30 days to 365 days—typically 60 days. Thus, the 3-sigma limits for a variable, set at 99.865 and 0.135 percentile levels, indicate that 99.73% of the data points fall within the 3-sigma region, assuming normal distribution of data points, which is justified based on the Central Limit Theorem for large number of independent data points.
[0175] In addition, the second levels of alarms (step AF601b), that is, H2 and L2 alarms are placed at +/−4 sigma limits, which are set at 99.99685 and 0.00315, indicating that 99.9937% of the data points fall within the 4-sigma region. Because the 3-sigma and 4-sigma limits are updated periodically, the alarm levels are consequently also updated dynamically as well.
[0176] Long-term moving averages (LTMA) for Time Segments: Two types of long-term moving averages are defined for time segments: (a) long-term exponential moving average (LTEMA), and (b) long-term simple moving average (LTSMA). “Long-term exponential moving average” (LTEMA) for any of the time segments discussed above, refers to exponential-weighted moving average calculated using a given number of time segment values. The number of values is selected depending upon the variable, as well as on the alarm system. For example, recommended LTEMA calculations are made using the last 200 values, ranging up to at least 500 values or more. By comparison; for cases with less than 50 data points identified within 365 days, the recommended LTEMA calculations are made using the last 50 values, ranging down to a few as 25 values.
[0177] LTEMA applies more weight to recent values. The magnitude of weights applied to the most recent values depends on the number of values in the moving time period. For example, in the case of an alarm with a set of 50 recovery time values (which occurred in a period of 60 days), the LTEMA of the alarm's last 50 recovery times is calculated as follows:
[0000] Multiplier=(2/(Number of values+1))=(2/(50+1))=0.0392 [Equation 6]
[0000] LTEMA(50−value)={Current value−LTEMA(previous value)}*multiplier+LTEMA(previous value). [Equation 7]
[0178] “Long-term simple moving average” (LTSMA) for a time segment refers to simple moving average of time segment values that occurred in a given long-term time period. Here, the long-term time period is selected anywhere between 30 to 365 days—typically 60 days. For cases with less than 5 data points in 60 days, the long-term time period is selected to ensure that at least 5 data points are included for calculations.
[0179] LTSMA applies equal weights to all the data pints. For example, consider the above case of alarm with 50 recovery time values in a period of 60 days. The LTSMA of its recovery times in last 60 days is calculated as follows:
[0000]
LTSMA
(
60
-
day
)
=
∑
?
=
?
?
?
recovery
time
50
?
indicates text missing or illegible when filed
[
Equation
8
]
[0180] An additional concept is added of a “rare alarm,” referring to an alarm that occurs very infrequently or rarely in a given time period. This definition requires two quantities to be specified: (a) the maximum number of alarms, N 1 , and (b) the minimum time period, T 1 . The value of N 1 is an integer between [0, 20] and T 1 ranges from 30 to 365 days. A typical qualification for a rare alarm is the occurrence of the given alarm ≦5 times in more than a 60 day time period.
[0181] Rank Variation Charts of Alarms and Variables: A mechanism is provided to compare and assess the changes in the ranks of alarms and/or variables. The rank variations charts (and lists) provide an easy mechanism to quantify and compare the shifts in the ranks of alarms and/or variables. The variations also help identify the alarms and/or variables that experience the maximum change (increase or decrease), to the attention of plant/facility personnel.
[0182] To accomplish this rank variation mechanism, two alarm or variable lists are taken: (1) Current list and (2) Reference list. The “current list” is the list which the user wants to use to compare with the “reference list;” the “reference list” is the list which the user wants to compare against. To demonstrate the concept, if the reference list is list of 10 top alarms based on Average Recovery Time criteria for the most recent week, and if the comparison list is list of alarms based on Average Recovery Time criteria for 3 weeks ago, then the rank variation mechanism permits an assessment of how the ranks of top 10 alarms in the reference list change from the alarms as ranked in the comparison list. For example, if PI-400 (H1 alarm) is ranked at Rank #1 for the most recent week, whereas, 3 weeks ago the same alarm was Rank #50, then the comparison is shown as
[0000]
Rank
Rank
Item
(Current list)
(Reference List)
Change
PI-400, H1 alarm
1
50
49↑
LI-100, H2 alarm
2
1
1↓
Reference List: Average Recorded Time, Aug. 1, 2011
Comparison List: Average Recorded Time, Jul. 1, 2011-Jul. 8, 2011
[0185] The same information is presented as a chart in FIG. 23 , and a chart showing “maximum change” is presented as FIG. 24 , wherein x-axis shows the absolute change, y-axis shows the variable/alarm.
[0186] Risk Arrow: An arrow with changing widths: is used when a list of items is based on change(s) in the risk level. When the list is not arranged according to increasing/decreasing risk levels (e.g., when the items are arranged alphabetically or chronologically), the risk arrow does not appear. However, the utility of the risk arrow is that (a) it shows the direction of increasing (or decreasing) risk for a list of items, and (b) quick identification of high-risk items.
[0187] II. Dynamic Risk Analyzer
[0188] The Dynamic Risk Analyzer system (DRA) assesses operational risks in a plant/facility by characterizing its deviations from long-term behavior of the process. DRA increases the capacity of plant management team, such as plant managers, area supervisors, operators, and anyone else, such as insurance companies, who are interested in continuously assessing the risk level of operations as measured by deviations from the normal operating conditions, to better understand the important issues to be addressed for healthier operations, that is improved safety, operability, and reliability.
[0189] FIG. 25 schematically illustrates the DRA system and its three components, denoted by 1) a Prominent Transitions Analysis (DRA100), including a subsets Grading and Ranking of Transitions, and Prominent Transitions for Discrete Sigma Levels; 2) a Dynamic a Dynamic Risk Index (DRA200); and 3) a Compounded Risk Score (DRA300).
[0190] The DRA calculations are based on analysis of historical alarm data and process data, conducted periodically (daily, weekly, monthly, etc.). “Process data” means data resulting from real-time measurements of both alarm and non-alarm based process variables associated with a plant/facility, including temperature, pressure, and the like, when real time assumes its normal meaning. More specifically, “process data” is the collection of all or at least some of the values of “process parameters” that are measured, and recorded/reported by the DCS (Distributed Control System, below) or any other device that automatically measures the value of one or more variables and reports the date either in-real time or periodically, or both. Process data include, for example, values including temperature measured in a reactor, at an inlet stream or an outlet stream, pressure of a reactor, flow rate of a liquid or gas going into or out of a reactor, liquid level in a reactor or a tank, and the like. In large industrial operations there are about 300 process variables that are measured and reported in the prior art. An industrial manufacturing operation centered around a reactor would have several parameters that are associated with that “reactor unit” (reactor and its associated peripheral equipment). Also there are several parameters associated with a liquid flowing into a reactor: its temperature, pressure, viscosity, etc. Together the values of all these parameters comprise “process data.”
[0191] At least two types of alarms are defined in a plant/facility: ‘H’ alarms and ‘L’ alarms. For any variable, “H alarms” refer to those alarms which are set at thresholds, greater than the median value of the variable in a selected training data (typically 60-90 days). “L alarms” refer to those alarms which are set at thresholds, lesser than the median value of the variable in a selected training data. Often, H alarms include multiple levels of alarms indicated by ‘H1 alarm,’ ‘H2 alarms,’ and so on. Similarly, L alarms also include multiple levels of alarms indicated by ‘L1 alarms,’ ‘L2 alarms,’ and so on. The suffix number for H alarms and L alarms increase as the threshold values increase above or decrease below the median value, respectively. For example, for an H alarm, the threshold for an H2 alarm is greater than the threshold value for an H1 alarm, whereas the threshold for an H3 alarm is greater than the threshold value for an H2 alarm, and so on. Similarly, for L alarms, the threshold for an L2 alarm is less than the threshold value for an L1 alarm, whereas the threshold for an L3 alarm is less than the threshold value for an L2 alarm and so on. Moreover, often H1 alarms and L1 alarms are referred as first level alarms, H2 alarms and L2 alarms are referred as second level alarms, and so on. The thresholds at which each alarm is set is determined by plant/facility personnel during the commissioning of the plant/facility and are updated regularly (typically every 6 months to 1 year).
[0192] II.A. Prominent Transitions:
[0193] The concept of “prominent transitions” is introduced as defined as, identifying the riskiest transitions in the alarm activations, going from one level to the next for a given variable, wherein risk and riskiest were terms defined above in Subsection I. This new concept also enables one to analyze and compare the transitions between alarm levels of different variables, as well as for different time periods. These calculations are done periodically (such as after every shift, every day, every week, etc.), and the results are compared to identify the riskiest (or most prominent) transitions, as explained below. However, briefly, variables having more than one alarm level are measured and recorded, and the transitions from one alarm level to the next are analyzed and prioritized based on risk behavior.
[0194] Definition of Outer and Inner Levels of Alarms: The terms ‘Outer’ and ‘Inner’ levels of alarms are introduced to refer to alarm levels in a relative manner. For example, when the first level of alarms is the reference level, the second, third, and subsequent levels of alarms are referred as “outer levels.” By comparison, when the second level of alarms is the reference level, then the first level of alarms is referred as an “inner level,” whereas, the third, fourth, and subsequent levels of alarms are referred to as “outer levels” relevant to the reference level. By example, if an alarm system has three layers of alarms—when the H1 alarm/L1 alarm is the reference level, then the H2 alarm/L2 alarm and the H3 alarm/L3 alarm are outer levels relevant to the reference level. If the H2 alarm/L2 alarm is the reference level, then the H3 alarm/L3 alarm is an “outer level,” and the H1 alarm/L1 alarm is an “inner level.” If the H3 alarm/L3 alarm is the reference level, then both the H1 alarm/L1 alarm and the H2 alarm/L2 alarm are inner levels.
[0195] Tiers of Transitions: Different tiers of Transitions are defined as follows, wherein tier assumes its recognized meaning of a grade or level of transition:
Tier I transitions are those transitions that occur from first level of alarms (reference level) to second level of alarms (outer level). The transitions are shown as H1->H2, or L1->L2. Tier II transitions are those transitions that occur from second level of alarms (reference level) to third level of alarms (outer level). The transitions are shown as H2->H3, or L2->L3. Tier III and Tier IV transitions are similarly defined. In addition, combo tiers are defined—e.g., Tier I-II transitions are those transitions that occur from first level of alarms (reference level) to third level of alarms (outer level), that is, from H1->H3 or L1->L3.
[0200] However, for the purposes of this invention, only transitions from a reference level to an outer level are considered; more specifically, transitions from a reference level to an inner level are not considered.
[0201] Grading of Transitions in a Given Time Period: A method DRA101 is illustrated in FIG. 26 to grade and rank transitions in a given time period (e.g., days, weeks, months, custom time period), also referred as test period. First, a tier of transition and an appropriate training period for data (ranging from 1 month to 2 years) are selected. The calculations, as next described, are applicable to various different types of tiers of transitions.
[0202] Three criteria, used individually or in combination, are considered to grade the transitions in a “test period,” which refers to a given time period being analyzed These include:
(a) Number of abnormal events crossing the outer level: For each transition, the number of abnormal events that crossed the outer level of alarms relevant to the reference level are considered. For example, for H1->H2 transition for a variable, all of its second stage abnormal events that cross the H2 alarms are counted. Previously discussed FIGS. 12 and 13 show two scenarios, respectively, each representing an abnormal event; and (b) Probability of crossing the outer level: To calculate the probability of crossing the outer level (with respect to reference level), three additional types of calculations are introduced—frequency-based, duration-based, and area-based, which are presented in greater detail below. (c) Average acceleration time to cross the outer level (with respect to reference level): The values of all the acceleration times (associated with the abnormal events) in a given time period are recorded and their average is calculated. In some cases, the median values are considered instead of the average values.
[0206] Thus, for a transition, H1->H2, the acceleration times associated with all of the 2nd stage abnormal events that cross the H2 alarms are taken, and their average value is calculated in this criterion.
[0207] Frequency-based calculations: Frequency-based calculations use the data on the number of abnormal events that cross the outer level and the reference level. Classical statistics and Bayesian statistics are used to calculate the mean probabilities of crossing the outer level with respect to reference level, written as follows: “Let the number of abnormal events that cross the reference level and the outer level be denoted as N 1 and N 2 .” Thus, using classical statistics, probability of crossing the outer level=N 2 /N 1 .
[0208] In Bayesian statistics, any abnormal event that crosses the reference level has one of two possible outcomes: 1) success, when it returns within the reference level, without crossing the outer level; and 2) failure, when it crosses the outer level. Thus, the outcome is modeled as independent and identical Bernoulli trials with probability of crossing the outer level as θ. The prior distribution for θ is assumed to be Beta distribution (conjugate prior) with the shape vector [a 1 , b 1 ]. Terms a 1 and b 1 are calculated based on long-term averages of abnormal events that crossed the outer level and reference level in “training data.” For a given time period, wherein the success and failure counts are equal to (N 1 -N 2 ) and N 2 , the mean posterior value of probability of crossing the outer level is calculated as:
[0000]
N
2
+
a
1
N
1
+
a
1
+
b
1
[
Equation
9
]
[0209] Determining Priors based on Long-term Averages: The above parameters [a 1 , b 1 ] denote shape vectors for prior belief distribution. Herein, a new concept of choosing their values based on long-term averages is introduced. It is claimed that for a given variable or a group of variables, the value of a 1 is chosen as α N 2 , where N 2 denotes long-term average value of abnormal events that cross the outer level, calculated using a training set of data and α denotes a proportionality constant in (0,2]. Similarly, the value of b 1 is chosen as β N 1 −N 2 , where N 1 −N 2 denotes long-term average value of abnormal events that cross the reference level only, calculated using a training set of data and β denotes a proportionality constant in (0,2]. Again, the training set of data ranges between last 30 to 365 days (typically 60 days) and is updated periodically.
[0210] The values of α and β depend upon how much weight one wants to give to the prior belief in the posterior value. A recommended value for both α and β is 0.5 that denotes half as much emphasis on the prior belief as compared to the actual likelihood data (data for the time period in consideration). In summary, this probability value, obtained using Bayesian statistics, with priors based on long-term averages, is referred as “post probability value.” A method for its calculation is illustrated in FIG. 27 . As pointed out above, these probability calculations are done for a single variable as well as for groups of variables.
[0211] Consider a case when N 2 =0 for a time period. According to Classical Statistics, the probability of crossing the outer level=0. But that probability does not mean that the associated risk (of crossing the outer level) in that week is 0, or that the risk going forward is 0. In fact, according to Bayesian statistics, the posterior probability is non-zero, and is determined by a combination of prior belief and actual data in that week. Thus, the utility of determining priors based on long-term averages is that the determination incorporates long-term behavior (indicating ‘inherent risk’) in the posterior estimate, which indicates an updated value of ‘inherent risk.’ This allows plant/facility management to better track the changes in the risk profile, which may happen due to gradual changes in the alarm system, or forced changes in the operations; hence, enabling the plant/facility operators to take actions to prevent future problems.
[0212] Duration-based calculations: Duration-based calculations use the data on the times spent by the variable beyond the outer level, as well as the reference level of alarms in a given time period. Thus, using classical statistics, probability of crossing the outer level is defined in three ways:
[0000] (Total time spent by variable beyond the outer level)/(Total time spent by variable beyond the reference level) [Equation 10]
[0000] (Average time spent by variable beyond the outer level)/(average time spent by variable beyond the reference level) [Equation 11]
[0000] Average of [(time spent by a variable beyond the outer level)/(time spent by variable beyond the reference level)] [Equation 12]
[0213] In Bayesian statistics, the times spent by variable beyond any level are modeled using either of the three different distributions: (a) exponential distribution, (b) Weibull distribution, and (c) log-normal distribution. With an appropriate prior distribution (e.g., gamma distribution, which is conjugate distribution for exponential as well as log normal distribution, or a uniform distribution, etc.), posterior estimates for times spent by variable beyond any level are calculated using Bayesian theory.
[0214] Area-based calculations: Area-based calculations use the data on the total area traced by the variable beyond the outer level as well as the reference level of alarms in a given time period. Thus, using classical statistics, probability of crossing the outer level is defined in three ways:
[0000] (Total area traced by variable beyond the outer level)/(Total area traced by variable beyond the reference level) [Equation 13]
[0000] (Average area traced by variable beyond the outer level)/(average area traced by variable beyond the reference level) [Equation 14]
[0000] Average of [(area traced by a variable beyond the outer level)/(area traced by variable beyond the reference level)] [Equation 15]
[0215] In Bayesian statistics, the areas traced by variable beyond any level are modeled using either of three different distributions: (a) exponential distribution, (b) Weibull distribution, and (c) log-normal distribution. With an appropriate prior distribution (e.g. gamma distribution, which is conjugate distribution for exponential as well as log normal distribution, or a uniform distribution, etc.), posterior estimates for areas traced by variable beyond any level are calculated using Bayesian theory.
[0216] Determination of Criticality Levels for Transitions on an Absolute Scale: Using the categories ‘Δ 3 ’, ‘Δ 2 ’, and ‘Δ 1 ’, the three criticality levels are defined to characterize the transitions on an absolute scale. The corresponding calculations are similar to that of the Alarm Floods and Alarm Attacks section above.
[0217] To calculate the Criticality Levels, first, a training period is selected and transitions in that period are identified. The recommended range for a training period is 1 month to 2 years, typically 6 months. Next, for each transition (in test period), the three criteria defined above are calculated. Then, for each of the three criteria, different percentile levels (e.g., 25th, 50th, 60th, 70th, 75th, 90th, etc.) are determined from the values for all of the transitions during the training period. Thus, the method for determining a criticality level for a transition (in test period) is described in the following steps:
Classify a transition as Δ 3 , if the value of each criterion associated with that transition is above P 1 th percentile of the values for that criterion calculated using the training period (as explained above). Here, the value of P 1 ranges between [50, 100)—typical value is 75. Classify a transition as Δ 2 , if the value of any criterion associated with that transition is above P 2 th percentile of the values for that criterion calculated using the training period. Here, the value of P 2 ranges between [P 1 +10, 100)—typical value is 90. Classify the remaining transitions as Δ 1 transitions.
[0221] Relative Ranking of Transitions within a Given Criticality Level: The following describes the steps to determine the relative ranks of transitions within a given criticality level (‘Δ 3 ’, ‘Δ 2 ’, or Δ 1 ′). First, list all the transitions for a given criticality level. Then, prepare a list of transitions in a decreasing order for each of the three criteria to produce the transitions in decreasing order of their values, as determined per criterion calculations described above. Next assign ranks to the transitions in each list, ranking the top one as #1, as shown in calculations above. The finally, to determine the relative ranking of transitions within a given criticality category, a) obtain the final rank of each transition by adding the three individual ranks, and b) organize the final list in ascending order.
[0222] Prominent Transitions for Discrete Sigma Levels (DRA102): For any variable, a “discrete standard deviation level,” also known as “discrete sigma level,” refers to a threshold value that is a function of its mean and standard deviation value. The threshold value is calculated using “process data” per “training period.” Note that “training period” typically includes several months of “training data” which is typically, sampled every 5-sec, 10-sec, etc.; and which is based on the rate of change of value of the variable (with more rapidly than normal changing variables are sampled more frequently). “Discrete standard deviation level” is often referred as “n standard deviation level” or “n sigma level,” where ‘n’ is a real number, used to represent the level. For a particular value of ‘n’, two types of “n standard deviation level” are reported: ‘+’ value and ‘−’ value. The ‘+’ value of an ‘n-standard deviation level’ is denoted as “+n standard deviation level” or “+n sigma level;” and the ‘−’ value of ‘n-standard deviation level’, denoted as “−n standard deviation level” or “−n sigma level.”
[0223] There are two ways of calculating the “+n standard deviation level” and “−n standard deviation level.” In method (1), typically ‘n’ is chosen in the range [2, 6]. Clearly, as value of n increases, the associated sigma levels move away from the mean value. The calculations are as follows:
[0000] + n standard deviation level’=mean value of variable calculated using “training data”+product of ‘ n ’ and standard deviation value of variable calculated using training data [Equation 16]
[0000] − n standard deviation level’=mean value of variable calculated using training data minus product of ‘ n ’ and standard deviation value of variable calculated using training data. [Equation 17]
[0224] In method 2, a large number, e.g., a million or more, of random samples are simulated from a Gaussian distribution with mean equal to 1, and standard deviation equal to 0. Then for a particular ‘n’, the ‘+n sigma level’ and the ‘−n sigma level’ are calculated for the Gaussian distribution using the steps of Method 1. Note that often “discrete sigma levels” are referred as simply “sigma levels.” Next, the percentage of data points that lie within the ‘+n sigma level’ and the ‘−n sigma level’ is calculated and denoted as ‘r.’ Then, the value of the ‘+n sigma level’ for the “training data” is equal to ‘p’th percentile value for “training data,” where p=(r+(0.5×(100−r))). Similarly, the value of the ‘−n sigma level’ for the “training data” is equal to ‘q’th percentile value for “training data,” where q=(0.5×(100−r)).
[0225] Method DRA101 is applicable for transitions from (a) an alarm level to another (calculated using alarm data), and (b) a “discrete sigma level” to another. The following tiers of transitions for sigma levels (all sigma levels mentioned below apply to both “+” and “−” sigma values) as defined:
Tier I transitions for sigma levels are those transitions that occur from 3-sigma level (reference level) to 3.25-sigma level (outer level). Tier II transitions for sigma levels are those transitions that occur from 3.25-sigma level (reference level) to 3.5-sigma level of alarms (outer level). Tier III transitions for sigma levels are those transitions that occur from 3.5-sigma level (reference level) to 3.75-sigma level of alarms (outer level). Tier IV transitions for sigma levels are those transitions that occur from 3.75-sigma level (reference level) to 4-sigma level of alarms (outer level). Higher tiers of transitions for sigma levels are defined similarly, having a gap of 0.25 sigma level. Combo tiers for sigma levels are defined, e.g., Tier I-II transitions for sigma levels as those transitions that occur from 3-sigma level (reference level) to 3.5-sigma level (outer level). Other types of tiers of transitions can also be defined when variable moves from a discrete sigma level to another. Thus, all steps of method DRA101 remain unchanged for sigma levels. Note that other tiers of transitions can be defined for various discrete sigma levels in a similar way.
[0233] II.B. Dynamic Risk Index
[0234] A method DRA200 to calculate “Dynamic Risk Index (DRI)” of a plant/facility is illustrated in FIG. 28 . “DRI” identifies risk levels of a plant/facility dynamically and provides information to operators, engineers, maintenance, and management on deviations of process from its long-term behavior.
[0235] First, a set of important variables, such as key performance indicators or variables that are associated with input to the process (such as flow rate of a reactant or coolant) is selected and their individual DRIs are calculated. These individual DRIs are used to obtain the DRI for the overall plant. The “important variables” are variables, which are considered to be significant for gauging safety, operability, and for determining risk levels. Note that the “important variables” may or may not be equipped with alarms, but are identified by the plant/facility personnel as being significant (“important”).
[0236] For each variable, the following steps are performed to determine its DRI for a select time period (such as daily, weekly, biweekly, monthly, and quarterly), referred as test period:
[0237] Step 1) Two types of analyses are considered: (i) alarm data analysis, and (ii) process data analysis. As discussed later, when the two analyses differ in their risk level estimates—say, one estimate is “RL3” and other is “RL1” (defined later)—then, the two estimates are combined to obtain the final risk level as the actual risk level associated with that variable. Note that for the variables that do not have alarms, only the process data analysis is performed. Moreover, under alarm data analysis, depending upon the number of alarm levels associated with the variable, the following criteria are considered:
Criteria #1: Number of abnormal events that crossed first level of alarm. Criteria #2: Number of abnormal events that crossed second level of alarm, and so on.
[0240] Next, a specific example (with more than one—in this case two alarm levels) is presented to show the possible criteria. Consider a variable with the following alarm levels: H1/L1 and H2/L2. In this case, the following criteria are considered for alarm data analysis:
(a) Criteria #1: Number of abnormal events that crossed ‘H1’ alarm level. (b) Criteria #2: Number of abnormal events that crossed ‘H2’ alarm level. (c) Criteria #3: Number of abnormal events that crossed ‘L1’ alarm level. (d) Criteria #4: Number of abnormal events that crossed ‘L2’ alarm level.
[0245] Under the process data analysis, the criteria are based on the number of abnormal events that crossed multiple “discrete sigma levels.” For example, the following criteria can be chosen:
Criteria #1: Number of abnormal events that crossed 3 sigma level. Criteria #2: Number of abnormal events that crossed 3.5 sigma level. Criteria #3: Number of abnormal events that crossed 4 sigma level. Criteria #4: Number of abnormal events that crossed −3 sigma level. Criteria #5: Number of abnormal events that crossed −3.5 sigma level. Criteria #6: Number of abnormal events that crossed −4 sigma level.
[0252] Step 2) Next, for both type of analyses (alarm data analysis and process data analysis), the following calculations are performed.
(a) For each criterion, a point value of ‘m’ is assigned. Typically m ranges from [1, 5]. ‘m’ is equal to one (1), when the value of criterion is more than its long-term average (this scenario indicates an increase in risk level with respect to long-term average). ‘m’ is equal to zero, when the value of criterion is less than or equal to its long-term average. (b) For alarm data analysis, the sum of points (for all associated criteria) is obtained, and is denoted M 1 , and for process data analysis, the sum of points (for all associated criteria) is obtained and is denoted by M 2 . In addition, for alarm data analysis, the maximum possible value of M 1 , denoted by M 1,max , is obtained by assuming each associated criterion to be more than its long-term average and summing all the points. Similarly, for process data analysis, the maximum possible value of M 2 , denoted by M 2,max is obtained by assuming each associated criterion to be more than its long-term average and summing all the points. (c) For alarm data analysis, divide, zero to M 1,max , into ‘n’ categories and for process data analysis, divide zero to M 2,max , into ‘n’ categories. Each category refers to a risk level, and referred as RL1, RL2, . . . , RLn. Typically, ‘n’ is 3 and the three risk levels are referred as RL1, RL2, and RL3. Clearly, RL3 indicates a riskier level than RL2, and RL2 indicates a riskier level than RL1. Next, for alarm data analysis, depending upon value of M 1 , a risk level is identified and for process data analysis, depending upon of M 2 , a risk level is identified. A fourth category of risk level “Shutdown,” can also be added and assigned when the variable leads to a shutdown.
[0256] Thus, for each variable, two values of risk levels are obtained—one from alarm data analysis and other from process data analysis. Then, the two risk levels are combined or averaged to obtain value of a single “dynamic risk index” for the variable. Multiple indices may be calculated. Unless the two are the same, typically the worse of the two risk levels is chosen as the final dynamic risk level for the variable. As mentioned above, the steps (a) to (c) are carried out for each of the important variables, generating several DRI values.
(d) Next, all DRIs calculated for the important variables, are pooled and combined or averaged to obtain the DRI for the overall unit. Typically the worst risk level is chosen as the final DRI for overall plant/facility. In case of a production unit shutdown in a given time period, the DRI is reported as “Shutdown.”
[0258] II.C. Compounded Risk Score (CRS):
[0259] “Compounded Risk Score” is one of the leading risk indicators (LRIs) of DRPS that calculates risk associated with a variable, group of variables, unit, interlock, or overall plant/facility over a period of time. It provides a mechanism to quantify the risk profiles based on their associated online measurement data. A method DRA300 to calculate “compounded risk score” is illustrated in FIG. 29 .
[0260] Definition of “Risk Zones” and Discrete Grades within a Risk Zone: For any variable, based on “discrete standard deviation levels,” multiple “risk zones” are defined. For example, considering 3-sigma and 4-sigma levels as boundaries of a “risk zone,” 3 different risk zones are defined. Similarly, considering 2-sigma, 2.5 sigma, 3-sigma, 3.5 sigma, 4-sigma, 4.5 sigma, 5-sigma, 5.5 sigma, and 6-sigma levels as boundaries of different risk zones, 10 different risk zones are defined.
[0261] For any variable, based on these high discrete standard deviation levels, multiple risk zones are defined. For example, considering 3-sigma and 4-sigma levels as boundaries of risk zones, 3 different risk zones are defined. Similarly, considering 2-sigma, 2.5 sigma, 3-sigma, 3.5 sigma, 4-sigma, 4.5 sigma, 5-sigma, 5.5 sigma, and 6-sigma as boundaries of risk zones, 10 different risk zones are defined.
[0262] Herein, a specific example is taken in which three risk zones are defined and referred as: “Z1,” “Z2,” and “Z3,” with 3-sigma and 4-sigma as the separating boundaries respectively. In other words, whenever a variable moves beyond its 3-sigma level (but remains within its 4-sigma level), it enters into its “Z2” zone; when a variable moves beyond its 4-sigma level, then the variable enters the “Z3” zone. For “Z2” and “Z3” zones, several intermediate grades are defined. To assign an appropriate grade within any risk zone, the following four criteria are defined:
1. Number of abnormal events crossing the associated sigma level. 2. Probability of crossing the associated sigma level. 3. Total recovery time for the associated sigma level. 4. Average acceleration time for the associated sigma level.
[0267] For example, for “Z2” zone, the four criteria are: (1) number of abnormal events crossing 3-sigma level, (2) probability of crossing 3-sigma level, (3) average recovery time for 3-sigma level, and (4) average acceleration time for 3-sigma level (from 2-sigma level).
[0268] A select time period is chosen (referred as “test period”) and values of above criteria are calculated. When value of any criteria is higher than its long-term moving average, a select number of up arrows (⇑) are assigned—indicating an increase in risk level with respect to its normal operations/behavior. Similarly, when the value is lower than its long-term average value, a select number of down arrows (⇓) are assigned—indicating a decrease in risk level with respect to its normal operations/behavior. The following rules are used to determine the number of arrows to be assigned in a given case:
(a) For a given criterion, when the magnitude of deviation with respect to normal operations is very high, such as 50% increase or decrease, multiple arrows (e.g., two or three) are used. (b) If a given criterion is considered more important than the others, multiple arrows are used for the former to put more weight on deviations thereof.
[0271] In a specific example, the assignment of the arrows is shown, wherein a single up or single down arrow is assigned to indicate increase or decrease in risk level with respect to normal operations. Consequently, for this example, 5 grades are obtained for each risk zone:
⇑⇑⇑⇑: Grade 5: Values of all four criteria are higher than their LTMAs. ⇑⇑⇑⇓: Grade 4: Values of three criteria are higher and one is lower than the LTMAs. ⇑⇑⇓⇓: Grade 3: Values of two criteria are higher and two are lower than the LTMAs. ⇑⇓⇓⇓: Grade 2: Value of one criterion is higher and three are lower than the LTMAs. ⇓⇓⇓⇓: Grade 1: Values of all four criteria are lower than their LTMAs.
[0277] Compounded Risk Score for a Variable:
[0278] The Compounded Risk Score for any variable is obtained by identifying (a) the maximum risk zone it entered and (b) an associated grade because of that entry. The different possible CRSs in descending order are as follows:
[0000]
Compounded Risk Score
Criteria
Shutdown
Variable crossed ESD level, followed by
a shutdown
Z3 (Grade 5) or (Z3) 5
Variable crossed 4-sigma and ↑↑↑↑
Z3 (Grade 4) or (Z3) 4
Variable crossed 4-sigma and ↑↑↑↓
Z3 (Grade 3) or (Z3) 3
Variable crossed 4-sigma and ↑↑↓↓
Z3 (Grade 2) or (Z3) 2
Variable crossed 4-sigma and ↑↓↓↓
Z3 (Grade 1) or (Z3) 1
Variable crossed 4-sigma and ↓↓↓↓
Z2 (Grade 5) or (Z2) 5
Variable crossed 3-sigma and ↑↑↑↑
Z2 (Grade 4) or (Z2) 4
Variable crossed 3-sigma and ↑↑↑↓
Z2 (Grade 3) or (Z2) 3
Variable crossed 3-sigma and ↑↑↓↓
Z2 (Grade 2) or (Z2) 2
Variable crossed 3-sigma and ↑↓↓↓
Z2 (Grade 1) or (Z2) 1
Variable crossed 3-sigma and ↓↓↓↓
Note that superscripts following “Z2” in the Compounded Risk Score column refer to Grade of Risk within the Z2 zone.
[0279] Organization of Variables Based on their Compounded Risk Score: By organizing the variables according to their Compounded Risk Score, identification of those variables is enabled that deviate most from their normal operations. The Compounded Risk Score for a group of variables is calculated by taking the highest value of compounded risk scores associated with the given group of variables. In both the diagram provided as FIG. 30 and the bar graph in FIG. 31 , an exemplary Compounded Risk Score is provided for Variable A over a period of 6 weeks. As seen the bar at three weeks prior to the current week (designated “last week”), the compounded risk score was Z3 (Grade 5). At 5 weeks prior to the same current week, there was a shutdown, which overrode other risk factors in that week—hence, the compounded risk score is indicated as ‘Shutdown,’ shown as a black bar. Thus, “compounded risk score” calculations are applicable for a variable, group of variables, unit, interlock, or overall plant/facility over a period of time.
[0280] III. Real-Time Leading Signal Generator
[0281] The Real-time Leading Signal Generator system LI (illustrated in FIG. 32 ) informs operators of a plant/facility of the potential of incidents or catastrophe in real-time by issuing warning signals based on process data, obtained in real-time. In addition, the system reports real-time risk status to the plant/facility personnel to depict the health of the operation in real time. The methods presented in Real-Time Leading Signal Generator system increase the capacity of operators to prevent accidents, quality deviations, and unexpected shutdowns, by identifying significant risks as extent of deviations of process variables from normal operating conditions, within a time frame that enables an advanced corrective action to be taken in a timely manner (in most cases).
[0282] “Real-time” as used herein does not refers to the actual time during which a process or event occurs, nor does it relate to a system in which input data is processed within milliseconds, so that it is available virtually immediately as feedback, e.g., in a computerized system; rather in the present context the term refers to calculations that are made and the results are used in a just-in-time manner. In other words the real-time process for the leading signal generator calculates long-term trends over predetermined time periods, but wherein during that time, for every second (or 5 seconds or more in a preset period), when the data is measured, the collected data associated with the variable is compared against the long-term or historical data to determine if the newly collected data significantly deviates (percent deviation) from the long-term data, or not. If it is deviated more than a predetermined value as explained in the method a leading signal alert is automatically issued as a message or symbol with associated information indicating the variable that has deviated, as described in the flag process below.
[0283] The LI system includes the following two methods: 1) Generation of Real-time Leading Signals (LI100); and 2) Real-time Risk Indicator (LI200). A “leading signal” is an alert in the form of a text, symbol, or combination thereof, which indicates that the particular variable with which it is associated, has deviated from normal or long-term plant/facility operations more than the predetermined percent deviation that the plant/facility has previously established as acceptable to their business. As a result, the existence of a leading signal with regard to an operation indicates that there is a potential risk of an adverse incident, accident or unplanned shutdown. “Normal” as used herein therefore, is predetermined by the plant/facility as an acceptable or historically acceptable level of operation or of a variable in the operation, in contrast to an abnormal situation in which the leading signal is applied and risk potential is changed or elevated above normal, or above predetermined critical levels.
[0284] Definition of Pre-flag Limits: For a variable, “pre-flag limits” refer to boundaries that enclose X percent of data points in “training data.” X ranges from [75, 100)—typically value being 98. “Training data” includes several months of data, sampled every 5-sec, 10-sec, etc., and based on the rate of change of value of the variable (more rapidly than normal, changing variables are sampled more frequently). Typically, training data includes 1 month of data, with data points available at every 5-sec or 1-sec. In the case in which the variable is sampled at a frequency higher than 5-sec or 1-sec, interpolation is done to obtain values at those time instants. Two types of “pre-flag limits” are defined: “+ pre-flag limit” and “− pre-flag limit.” Typically, the “+ pre-flag limit” is set at 99th percentile value and “− pre-flag limit” at 1st percentile value, calculated using the training data. The utility of pre-flag limits is that the region that they enclose depicts normal operating conditions.
[0285] Generation of Real-Time Leading Signals: A method LI100 to generate “Real-time Leading Signals” is illustrated in FIG. 33 . These “leading signals” forewarn the operators and personnel at the plant/facility of potential of incidents (including shutdowns). The leading signals are typically calculated for select important variables—which are either specified by plant/facility personnel or depict critical process parameters. The idea is to monitor the trajectory of a variable and determine the deviations from different running averages at select time intervals to identify risky situations and issue leading signals accordingly. The following provides a summary of methodology of calculation of leading signals for a given variable.
[0286] Calculations of Leading Signals: First identify training data, and calculate the “pre-flag limits” using the training data. Next, identify a test period and at a select “frequency,” obtain measurement value. Frequency refers to a time interval (such as 5-sec, 10-sec, etc.) at which a variable measurement value is obtained. At each time instant when a measurement value is obtained, identify whether the value is “qualified” or not by verifying whether it is more than “+ pre-flag limit” or less than “− pre-flag limit.” For each qualified measurement value, calculate (a) running average values over select period of time (including the current value), such as 2-hour, 12-hour, etc. and (b) “percentage deviations” of the current measured value from these averages. A percentage deviation is defined as follows:
[0000] % deviation=100*((Measurement value−running average value)/(running average value)). [Equation 18]
[0287] Notably, the percentage deviations must be calculated for at least two different running averages, e.g., for 2-hour and 12-hour. Whenever any of the percentage deviation values is more than a cutoff value (e.g., 25%), a “violation” tag is assigned and a leading signal is issued. At any instant, the total number of “violation” tags determines the strength of the leading signal. The higher the strength, the more powerful is the leading signal. Moreover, cutoff values can be selected differently for different running averages.
[0288] Music Bar Chart: A novel concept of “Music Bar Chart” is defined to display the number of violations (defined above) associated with select variables. For a given variable, a “bar” is assigned for each violation. For example, in a Music Bar Chart as shown in FIG. 34 , all the bars, associated with the variables, are displayed as a stack. PI-100 and TI-200 are exemplary variables. At any time instant, Music Bar Chart shows the number of violations tags associated with select important variables. For a given variable, a bar represents each violation tag. Because the number of violation tags changes with every time instant, the number of bars in the Music Bar Chart changes with time as well, giving an impression of a traditional Music chart. Thus the chart is an intuitive way of visualizing how violation tags (the bars) change with time, overall creating, that gives an impression of a media music chart.
[0289] Real-time Risk Indicator (RTRI): The concept of “Real-time Risk Indicator” is defined to assess and display how risk associated with various equipments and interlocks/ESDs in a plant/facility changes with time. See, FIG. 35 . For any variable, based on “discrete standard deviation levels,” multiple “risk zones” are defined. For example, considering 3-sigma and 4-sigma levels as boundaries of a “risk zone,” 3 different risk zones are defined. Similarly, considering 2-sigma, 2.5 sigma, 3-sigma, 3.5 sigma, 4-sigma, 4.5 sigma, 5-sigma, 5.5 sigma, and 6-sigma levels as boundaries of different risk zones, 10 different risk zones are defined.
[0290] Herein, a specific example is taken in which three risk zones are defined and referred as: “Z1,” “Z2,” and “Z3,” with 3-sigma and 4-sigma as the separating boundaries respectively. First, for any variable, pre-flag limits are calculated using “training data.” For any variable, the “instantaneous risk status” at each measurement value in test period is calculated as follows. At any instant, when variable is within “+3 sigma level” and “−3 sigma level,” the “instantaneous risk status” is “Z1.” When variable moves beyond its “3 sigma levels,” but lies within its “+4-sigma level” or “−4 sigma level,” the “instantaneous risk status” is “Z2.” When variable moves beyond its “4-sigma levels,” the “instantaneous risk status” is “Z3.”
[0291] Based upon the above criteria, the following describes how RTRI is calculated, which includes all the equipments and interlocks of a plant/facility. At any instant, when any variable associated with an equipment/interlock moves beyond its “3 sigma levels” (but lies within its “4 sigma levels”), the “instantaneous risk status” of the equipment/interlock becomes “Z2.” At any instant, when any variable associated with an equipment/interlock moves beyond its “4 sigma levels,” the “instantaneous risk status” of the equipment/interlock becomes “Z3,” While, at any instant, when all the variables associated with an equipment/interlock is within its 3-sigma levels, the “instantaneous risk status” of the equipment or interlock is “Z1.”
[0292] IV. Near-Miss Surfer
[0293] The Near-Miss Surfer system (NMS; illustrated in FIG. 36 ) automatically identifies process problems, referred as “hidden process near-misses” that can potentially lead to accidents having a major impact on safety, operability, quality, and/or business. A “near-miss” as defined by the Webster Free Dictionary and as used herein means: something narrowly avoided; a lucky escape. A “near miss” for safety purposes is an unplanned event that did not result in actual injury, illness, or damage—but had the potential to do so. Only a fortunate break in the chain of events prevented an injury, fatality or damage; in other words, a miss that was nonetheless very near. Although the label of ‘human error’ is commonly applied to an initiating event, a faulty process or in this case a failed alarm or alarm system invariably permits or compounds the harm, and therefore provides a focus for improvement. Such events may also be considered a “close call.”
[0294] Most safety activities are reactive and not proactive, and as a result many organizations wait for losses to occur before taking preventative steps to prevent a recurrence. Near miss incidents often precede loss producing events, but they have been largely ignored because no injury, damage or loss actually occurred. Thus, many opportunities to prevent an accident or adverse incident are lost. However, recognizing and reporting near miss incidents, particularly measurable near misses, such as by alarms in an alarm-monitored plant/facility or by comparative data, such as the sigma data described herein, can make a major difference to the safety of workers within organizations, and often to the public at large, e.g., in the case of a nuclear-powered facility. History has shown repeatedly that most loss producing events (accidents) were preceded by warnings or near-missed accidents. Yet as disclosed above in alarm-monitored plants/facilities, these problems are identified using both alarm and process data.
[0295] A “process near-miss” is an event or a series of events associated with an operational process, which had the potential of becoming an “accident,” but did not result in one. These events can be treated as precursors to accidents, hence, can be utilized by plant/facility operators as well as management to improve the system performance and prevent potential accidents. Normally process near-misses are observable events which can be reported, recorded and used for system improvement purposes.
[0296] In the prior art, events that caused the near-miss are often subjected to root-cause analysis to identify the defect in the system that resulted in the error and to determine factors that may either amplify or ameliorate the result. However, the present invention extends beyond the observed near misses, and relies upon the discovery that for every accident there are not only near-misses, but much like an iceberg, there are even more “hidden process near-misses” or more simply, “hidden near-misses.” See FIG. 37 . Thus, there is valuable risk information buried in the data that is generated and collected during a process. But the hidden near-misses are not observable in the process data, unless and until extracted and converted into an information format.
[0297] Thus, the present invention defines and identifies hidden process near-misses using pre-determined criteria or algorithms, summarized below and in FIGS. 37 and 38 , which combine various riskiest changes or deviations in process conditions with respect to normal operations, that took place for a given unit in a given time period, and that could only be identified through rigorous calculations using process and or alarm data. As a result, “hidden process near misses” are defined as a deviation (or set of deviations) of a process condition as compared with its long-term or normal values. However, such near-misses are considered to be “hidden” because unlike the observed near misses, the hidden process near miss is not identifiable solely from current (whether normal or not) values of an associated variable or alarm. To the contrary, the current value of the variable or alarm has to be carefully compared against the long-term performance of the same elements to be able to identify the hidden near-misses.
[0298] As a result, most process near-misses are identified using one or more leading risk indicators as defined herein. But rather than providing methods for uncovering alarm or variable data, the present invention identifies and quantifies information within the data in the form of observed or observable near misses, and more particularly in the addition of information regarding hidden process near misses. Although recognizing their important differences, for simplicity of discussion, the sum of the observed or observable near misses, combined with and added to the hidden process near misses, are herein referred to together as “near misses,” and the information extracted from the combined data is “near miss information.”
[0299] Managing near-misses, that is identifying them and taking corrective action to prevent the recurrence of underlying problems, is an important practice in all industries in reduction of accidents and improvement of safety, operability, reliability, and quality. Current practice of near-miss management is limited to identification of near-misses by observation or by experiencing a particular problem. These are denominated generally herein and in FIG. 37 , as “observed near misses.” Near-Miss Surfer system identifies issues that can only be recognized by rigorous calculations explained by the methodologies mentioned herein. These methods help identify issues (generally referred to herein as “hidden process near misses”) before they become visible or observed near-misses, which in some cases can be too late to manage, that is to prevent the undesirable outcome.
[0300] The concept of “near-misses” is of particular value when associated with personal safety, but it can also represent significant economic savings to the plant/facility. In the case of process or operational issues, the associated near-misses (referred as “process near-misses”) are usually identified and reported by individuals, such as plant/facility operators, involved in the day-to-day operations. By comparison, similar reporting of near-misses associated with personal safety is referred to as a “personal near-miss,” but for the purposes of this invention, both personal and process near-misses are referenced together as “process near-misses.”
[0301] Advantageously the presented methodology of identifying, classifying, and reporting “process near-misses,” associated with a given process, occurs automatically—without any human intervention, including the management of far more alarm instances at a given time or over a longer period than could be processed by an individual.
[0302] The NMS system comprises at least the following methods, which will be described in greater detail below: 1) Automatic detection and classification of Hidden Process Near-Misses; 2) Hidden Process Near-Misses based on Alarm Frequency Analysis; 3) Hidden Process Near-Misses based on Abnormal Events Analysis; 4) Hidden Process Near-Misses based on Time Segment Analysis; 5) Hidden Process Near-Misses based on Dynamic Risk Analysis; 6) Hidden Process Near-Misses based on Real-time Leading Signals Calculations; and 7) Hidden Process Near-Misses based on Quality Measurements.
[0303] Automatic detection and classification of Hidden Process Near-Misses: A method NMS100 to detect and classify “hidden process near-misses” automatically is illustrated in FIG. 38 . The following criteria are used to identify and classify “hidden process near-misses” over a given period of time (daily, weekly, monthly, etc.).
[0304] 1. Hidden Process Near-Misses based on Alarm Frequency Analysis: A “hidden process near-miss” is identified when one or more of the following conditions are met.
a) If for a variable, or group of variables, the alarm frequency of any type (1 minute, 10 minute, hourly, daily, weekly, biweekly, monthly, etc.) for any period is more than a cutoff value. The cutoff value is set equal to the boundary between the associated “Moderate Frequency Zone” and “Extreme Frequency Zone” or the boundary between the associated “Normal Operations Zone” and “Moderate Frequency Zone” (as defined for “classified alarm frequency” charts), or at a fixed value defined by plant/facility personnel. b) When a “Δ 3 alarm flood” or “Δ 2 alarm flood” or “Δ 1 alarm flood” occurs. c) When a “Δ 3 alarm attack” or “Δ 2 alarm attack” or “Δ 1 alarm attack” occurs.
[0308] 2. Hidden Process Near-Misses based on Abnormal Events Analysis: A “hidden process near-miss” is identified when one or more of these conditions are met.
a) If any variable crosses its “shutdown limits” without resulting in any shutdown. These abnormal events are defined as “ultimate abnormal events.” “Shutdown limit” refers to the threshold value, which when exceeded either triggers automatic shutdown of an equipment/area of plant/facility, or of entire plant/facility, or activates safety instrumented systems. As indicated, the shutdown limits are specified by plant/facility personnel during the commissioning of the plant. b) When a “1st stage abnormal event,” or “2nd stage abnormal event,” or “3rd stage abnormal event,” or “nth stage abnormal event” occurs for a variable, where ‘n’ is the total number of alarm levels for the variable. c) If for a variable or group of variables, the abnormal event frequency for any period is more than a cutoff value. The cutoff value is set equal to the boundary between the associated “Moderate Frequency Zone” and “Extreme Frequency Zone” or to the boundary between the associated “Normal Operations Zone” and “Moderate Frequency Zone” (defined as above using classified charts for abnormal events frequency), or at a fixed value defined by plant/facility personnel. d) If for a variable, “risk score,” or “effective risk score” associated with any abnormal event is more than a cutoff value. The cutoff value is set at a high percentile value, calculated using a training set of data, for example, 90th percentile calculated using risk scores or effective risk scores based on the “training data” (for example, set for the last 30 days of data), or at a fixed value defined by plant/facility personnel.
[0313] 3. Hidden Process Near-Misses based on Time Segment Calculations: A “hidden process near-miss” is identified when one or more of the following conditions are met.
a) If for a variable, its “recovery time” or “effective recovery time” associated with any alarm level is more than a cutoff value. The cutoff value is set at a high percentile value, calculated using a training set of data, for example, 90th percentile calculated using recovery times or effective recovery times based on a “training data” (for example, 30 days of data), or at a fixed value defined by plant/facility personnel, for example, 2 hours. b) If for a variable, its “inter-arrival time” or “effective inter-arrival time” associated with any alarm level is less than a cutoff value. The cutoff value is set at a low percentile value, calculated using a training set of data, for example, 10th percentile calculated using inter-arrival times or effective inter-arrival times based on a “training data” (for example, last 30 days of data), or at a fixed value defined by plant/facility personnel, for example, 10 seconds. c) If for a variable, its “kick-off time” or “effective kick-off time” associated with any alarm level is less than a cutoff value. The cutoff value is set at a low percentile value, calculated using a training set of data, for example, 10th percentile calculated using kick-off times or effective kick-off times, based on a “training data” (for example, last 30 days of data), or at a fixed value defined by plant/facility personnel, for example, 10 seconds. d) If for a variable, its “acceleration time” or “effective acceleration time” (associated with any two alarm levels, wherein the alarm levels do not have to be consecutive alarms levels) is less than a cutoff value. The cutoff value is set at a low percentile value, calculated using a training set of data, for example, 10th percentile calculated using acceleration times or effective acceleration times based on a “training data” (for example, last 30 days of data), or at a fixed value defined by plant/facility personnel, for example, 10 seconds. e) If for any variable, its “deceleration time” or “effective deceleration time” associated with any two alarm levels (note: the alarm levels do not have to be consecutive alarms levels) is more than a cutoff value. The cutoff value is set at a high percentile value, calculated using a training set of data, for example, 90th percentile calculated using deceleration times or effective deceleration times based on a “training data” (for example, last 30 days of data), or at a fixed value defined by plant/facility personnel, for example, 2 hours. f) If for a variable, its “neighborhood time” or “effective neighborhood time” associated with any alarm level is more than a cutoff value. The cutoff value is set at a high percentile value, calculated using a training set of data, for example, 90th percentile calculated using neighborhood times or effective neighborhood times based on a “training data” (for example, last 30 days of data), or at a fixed value defined by plant/facility personnel, for example, 2 hours.
[0320] 4. Hidden Process Near-Misses based on Dynamic Risk Analysis: A “hidden process near-miss” is identified when one or more of the following conditions are met.
a) When a “Δ 3 transition” or “Δ 2 transition” or “Δ 1 transition” (for any tier of transitions) occurs. b) When “dynamic risk index” of a variable or group of variables or overall plant turns “RL2” or “RL3” or “RLn,” where ‘n’ refers to the total number of risk levels. c) If, for a variable or group of variables, the associated “Compounded Risk Score” is in “Z3” or “Z2” zone (any grade).
[0324] 5. Hidden Process Near-Misses based on Real-time Leading Signals Calculations: A “hidden process near-miss” is identified when one or more of the following conditions are met.
a) When a variable goes beyond certain “discrete standard deviation levels,” such as 3-sigma, 3.5-sigma, 4-sigma, 4.5-sigma, 5-sigma, 5.5-sigma, 6-sigma, etc., calculated using “training data.” b) When “instantaneous risk status” of an equipment or interlock in “Real-time Risk Indicator,” turns “Z2” and/or “Z3.”
[0327] 6. Hidden Process Near-Misses based on Quality Measurements: A “hidden process near-miss” is identified when one or more of the following conditions are met.
a) When an important product quality variable (e.g., viscosity, density, molecular weight, etc.), that is measured online, goes below (or above) a cutoff value that is totally unacceptable for the operation. This value is specified by the plant/facility personnel, e.g., if value goes below “−3-sigma level” (or above “+3 sigma level”) value, calculated using a “training data” (for example, last 90 days of data). b) If the total recovery time for a product quality variable in a given time period exceeds a cutoff value. The cutoff value is specified by the plant/facility personnel, e.g., 2 hours in a day, or similar predetermined periods or ranges of time or other conditions.
[0330] Accordingly most process near-misses are identified using one or more leading risk indicators, defined herein.
[0331] Accordingly, identification and analysis/calculation of observed near-misses together with hidden process near-misses in a plant/facility provide an opportunity to take corrective action to reduce or prevent the recurrence of underlying risks and/or problems as compared to the observed and/or hidden risk levels without such monitoring. Alarm occurrences, or changes in alarm patterns, at an alarm-monitored plant/facility offer an exemplary tool, but not the only tool, for measuring observed near miss and hidden process near-miss occurrences. The product of monitored near-miss/hidden near-miss occurrences results in a measurable reduction in the number of operational or personal accidents at the plant/facility, and improved safety and operability, including both reliability and quality of operation. Although an observed near-miss can be defined in many different ways depending in the criteria used to identify and measure its occurrence, a near-miss analysis provides an opportunity to improve environmental, health and safety practices (together referred to herein simply as “practices”) at a plant/facility based upon one or more observed conditions or changes in condition(s), or to reduce or prevent incident(s) with potential for a more serious consequences at the plant/facility. Added to the near-miss analysis is an analysis of hidden process near-misses, which while unobserved unless determined by the calculations and analyses of process and/or alarm data of the present invention to identify deviations from normal/long-term behavior that have the potential of serious consequences for process safety, reliability, quality and operability, such as an accident and/or an unplanned shutdown of the plant/facility.
[0332] When the hidden process near-misses are combined with observed near-misses in an analysis of process and/or alarm data at a plant/facility, the data provide opportunities to operating teams to improve safety, reliability, quality, and operability by at the plant/facility, by equipping the owners or operators with automatic and advanced information on potential problem areas, which in most cases are not otherwise identified or identifiable by regular process analyses.
[0333] Profilebook: A “profilebook” is utilized when the results of calculations performed by different modules of DRPS are stored as “profile pages” for each individual variable, alarm flood, alarm attack, transition, equipment, interlock, and the overall unit. These profile pages serve as a reporting system and a repository of information obtained from the associated set of calculations, providing easy access to detailed and/or historical information for each component of the System in an organized manner. Therefore, it eliminates the need to provide unnecessary details to the plant/facility operators and management on an ongoing basis, yet still provides them with such information as needed.
[0334] Individual profile pages are provided for a variable, including, but not limited to results for alarms associated with the variable(s) relating to one or more of: an “advanced alarm frequency analysis;” an “abnormal event analysis,” including for an “abnormal events matrix,” “risk scores” for associated abnormal events, and “abnormal events frequency analysis;” a “time segment analysis” and “notables;” “rank variation charts;” “prominent transitions” charts, if any, “dynamic risk index,” including results of “acceleration time” analysis and/or “probability analysis;” “compounded risk score;” “leading signals,” if any; and “real-time risk indicator.” Profile pages regarding alarms relating to equipment, to Interlock/ESD, and to the overall unit/plant or facility, are similarly provided. Regarding an alarm flood and/or alarm attack, profile pages are provided to show one or more of: individual characteristics of alarm floods and/or alarm attacks (e.g., criticality levels, duration, weighted alarms, intensity, share of significant alarms, etc., as defined in Alarm Fitness module; “time segment analysis” and “advanced alarm frequency analysis” for alarms that occurred during the alarm flood and/or alarm attack.
[0335] The disclosure of each patent, patent application and publication cited or described in this document is hereby incorporated herein by reference, in its entirety.
[0336] While the foregoing specification has been described with regard to certain preferred embodiments, and many details have been set forth for the purpose of illustration, it will be apparent to those skilled in the art without departing from the spirit and scope of the invention, that the invention may be subject to various modifications and additional embodiments, and that certain of the details described herein can be varied considerably without departing from the basic principles of the invention. Such modifications and additional embodiments are also intended to fall within the scope of the appended claims. | Provided are methodologies to properly assess and manage operational risks at operations sites, e.g., a manufacturing, production or processing facility, such as a refinery, chemical plant, fluid-catalytic-cracking units, or nuclear energy plant, or a biological or waste management facility, airport or even financial institutions, or at any facility in which operations are often accompanied by risk associated with many high-probability, low-consequence events, often resulting in near-misses. In some operations, processes are monitored by alarms, but the invention operates on either process data or alarm data. The methods are based upon measurement of one or more variables, and/or utilization and management of the concept of “hidden process near-miss(es)” to identify a change or escalation, if any, in probability of occurrence of an adverse incident. The methodologies combine a plurality of subsets (also useful independently) of dynamically calculated leading risk indicators for dynamic risk management. | 6 |
This application is a continuation of International Application Number PCT/ES00/00368 filed Oct. 3, 2000.
OBJECT OF THE INVENTION
The present invention relates to a heater device for active substances meant to heat a wick soaked in a-volatile active substance (such as an insecticide, air freshener, etc.) which is contained in a vessel which can be coupled to the heater device itself, so that by capillary action the active substance rises through the wick which emerges from said vessel into a neck provided in the device, in which are provided heating elements which are actioned by the corresponding plug of the device, which can be plugged into an electric power network.
The object of the invention is to provide a heating device based on electrical resistors, consisting of four single parts and optionally a fifth part, duly coupled to each other without requiring additional means of any sort, neither for attachment nor release of the vessel from the heating device, nor for establishing the direct connection of said contacts to the heating elements, and in turn a direct connection to the jack plug, such that said switch is permanently joined to the device and activation/deactivation of said device is achieved by a rotation of the plug relative to the general body of the device.
BACKGROUND OF THE INVENTION
Devices are known which are plugged into the electricity mains connection of a household or any other premises in order to achieve evaporation of an active substance, whether for an air freshener or to produce vapors to eliminate insects, bacteria, fungi, etc. which devices are based on a jack plug which through contacts provide electrical power to a heater, which may be comprised of resistors, which heat a wick which rises from a vessel containing the active substance, so that heating of the wick and thereby of the substance which flows in it by capillary action will cause the release of the active substance.
Devices of this type, although practical, easy to use and clean, without causing any hindrance, suffer from certain drawbacks and disadvantages such as a complex assembly of their components and the need of a switch for disconnection from the power supply, or disconnection by unplugging directly.
Also worth mentioning is that the leads which establish connection between the corresponding contacts and the resistors require handling in their assembly, stripping of the plastic insulation which coats the leads, cutting excess wire of the resistances themselves which must be arranged around the wick to generate the heat for evaporation of the liquid or active substance which, by capillary action, rises in said wick, and a connection system between each wire and the corresponding electrical power lead.
Also troublesome is the method for attaching the vessel to the device which in most known devices requires a special handling, as although devices exist in which coupling/removal of the vessel is simple, this is in expense of a minimum reliability of the attachment of said vessel as it occasionally releases on its own and falls to the ground due to its weight.
DESCRIPTION OF THE INVENTION
The device disclosed has been conceived to solve the abovementioned problems, as well as to provide additional characteristics as compared to conventional devices.
More specifically, the device of the invention is based on one hand in that it can only comprise four parts, optionally five, thereby providing a great simplicity of assembly, manufacture, reliability and use, which parts consist of an outer casing, an inner part for mounting the corresponding contacts, which contacts are considered as the third part, with the plug-bearing set as well as the plug itself forming the fourth part, while the fifth, optional part is a lid for the inner mount which covers the housing of the heater elements in the second part, with the second part provided with an axial neck which allows the wick to pass and elastic means for retaining and simple release of the corresponding vessel containing the active substance which is to be evaporated.
Both the outer casing and the inner part of body are preferably made of a plastic material, such as a polyolefin of a polyamide type (PA) or polypropylene (PP) or polybutyl terephthalate (PBT) or polyoxymethylene (POM) or polyphenyl sulphur (PPS), such that the casing is hollow and presents a fully open base for assembly of the inner part or body, a lateral projection with a neck for assembly of the corresponding plug carrier, which consists of two pins embedded in a molded part which forms the plug itself, such that this molded part has a pair of projections on its inner face which together with ribs provided for such purpose in the lateral neck of the case, form a means of coupling and retention of said plug on the casing, such that the plug is prevented from separating from the casing yet allowed to rotate about it, with the particular characteristic that the plug pins emerge through their inner part as axial segments, the ends of which stop against the contacts provided for such purpose and duly placed in the inner part or body, which contacts have a special configuration so that each one has an upper part in the form of a bridge for assembly and correct attachment to a wall of the inner part or body, as well as two salient parts staggered respect to each other and elastically deformable, on which may incide the ends of the inner extensions of the plug pins. The contact elements are arranged so that connection to the plug is established at two positions, at 90° to each other, while in an intermediate position the ends of the plug are in an area in-between the contacts, which area is recessed with respect to the salient parts against which stop the ends of the plug tabs, defining an inoperative position where there is no contact at all, therefore providing in this intermediate position which is unaligned with the others a deactivation of the device, that is, a position in which the electrical power supply is cut off without requiring a switch of any kind, nor conducting wires as in conventional systems since the electrical resistors to be placed on the passage neck provided on the inner part or body will make contact and be attached to the pins corresponding to the elements which form the aforementioned contacts.
Also worth mentioning is that the inner part or body is provided, in correspondence with the walls for mounting the contacts, with grooves or depressions in which the excess wire of the heating resistors is folded and straightened, thus avoiding the need to cut said excess wire segments which are suitably positioned as described above.
A further novel characteristic is that the inner part is provided with tabs which are arranged preferably in a diametric opposition which form the means for attachment and securing of said part inside the casing when it is inserted to its maximum penetration position in the casing.
Another novel characteristic is that said inner part is provided on its lower part, that is, in the area where the vessel is placed which contains the active substance to be evaporated, with an elastically deformable ring which in its resting positions tends towards an oval shape in order to retain the vessel in this position, through the latter's neck, while release of said vessel is achieved by pushing inwards an elastic sector of the general casing which incides on the narrowest part of said ring making its sides open and thereby resulting in the release of the vessel retained by these sides.
The fifth optional part is meant to be a lid for the previous part at the place where the heating elements and their wires are housed in the inner body. Its novel characteristic is that it may be used or not, without substantially altering the evaporation performance of the device as a whole. It stands out in that it is positioned self-centered around the inner part or body for the wick, and in that it also covers the heater housing, which may be for example resistors. This optional lid is kept in position by friction of the edge of its circular orifice on three small ribs parallel to the chimney axis made at 120° and in relief on the outer walls of the neck of the chimney of the inner part or body.
DESCRIPTION OF THE DRAWINGS
As a complement of this description and in order to aid a better understanding of the characteristics of the invention, in accordance with a preferred embodiment, a set of drawings is accompanied as an integral part of the description where, for purposes of illustration only and in no way meant as a definition of the limits of the invention, the following is shown:
FIG. 1 .—Shows a general perspective view of the four components or fundamental parts plus an optional part which make up the heating device for active substances in accordance with the object of the present invention, and whose five components are the outer casing, the inner part for mounting the two contacts, also shown in the figure, the corresponding jack plug and the optional lid.
FIG. 2 .—Shows a general perspective view of the inner part of the device for mounting the contacts, which are duly coupled to said part and in which are shown in an exploded view the electrical heating resistors and the two pins of the plug, although the plug body is not shown, with the inner ends of said pins meeting the contacts mounted on the aforementioned inner part.
FIG. 3 .—Shows a bottom perspective view of the device without the plug but revealing the shape of the elastic deformable bottom ring of the inner part meant for attachment and securing of the vessel which contains the active substance, as well as the elastic inner sector of the inner casing by which said inner ring is pressed on to release said vessel.
FIGS. 4 a and 4 b .—Show, finally, a perspective view of the entire device assembled and in an exploded view, clearly showing the case, the plug and in a discontinuous line the inner part which bears the contacts, provided with the passage neck in which is placed the wick which must be heated for evaporation of the active substance contained in the corresponding vessel which can be connected to and retained on the bottom part of the device itself.
PREFERRED EMBODIMENT OF THE INVENTION
As shown in the abovementioned drawings, the device of the invention comprises four fundamental parts or elements and a fifth optional part, the first of which corresponds to a general casing ( 1 ) with a cylindrical shape, the second to a part ( 2 ) which is to be mounted inside the former, the third consists of two elements ( 3 ) and ( 3 ′) which form the device contacts, the fourth component or part consists of the corresponding jack plug ( 4 ) and the fifth optional part ( 27 ) which is circular and flat in shape with edges, is used as a lid for the housing provided for one or more heating elements ( 20 ) and the corresponding attachment elements ( 21 ).
As regards the casing ( 1 ), it is open on the bottom and in correspondence with its lateral surface it is provided with a projection ( 5 ) from which branches a cylindrical body ( 6 ) in which is coupled the jack plug ( 4 ), which casing ( 1 ) in correspondence with the end described as its bottom open end comprises an elastic sector ( 7 ) which is formed between two axial slits ( 8 ) of the general cylindrical body of the casing ( 1 ), such that said elastic sector ( 7 ) is meant to carry out the function which corresponds to releasing the vessel which contains the active substance which is to be evaporated, as described further below.
Inside cylindrical neck ( 6 ) are provided a number of projections ( 9 ) with a length shorter than the height of the cylindrical neck ( 6 ).
Jack plug ( 4 ) consists of a body obtained by molding and in which are embedded the corresponding pins ( 10 ), with outer segments ( 11 ) for contact with the corresponding electrical power supply plug and with emerging internal segments ( 12 ) for contact to contacts ( 3 ) and ( 3 ′). Additionally, the body of the jack plug ( 4 ) has inferior projections ( 13 ) which provide a means for retention when coupling the body of plug ( 4 ) inside neck ( 6 ) of casing ( 1 ), when said projections ( 13 ) pass the inner end of ribs ( 9 ) of neck ( 6 ), thereby retaining plug ( 4 ) in casing ( 1 ) without allowing axial removal but allowing rotation, so that plug ( 4 ) may be positioned as the user wishes but always allowing its rotation and not its axial displacement.
Contacts ( 3 ) and ( 3 ′) are provided on one of their ends with a sort of bridge ( 14 ) in which are established oblique tabs ( 15 ), such that by means of this bridge contacts ( 3 ) and ( 3 ′) are mounted on walls ( 16 ) provided for such purpose in inner part ( 2 ), as said walls ( 16 ) are placed inside bridges ( 14 ) provided at the top end of contacts ( 3 ) and ( 3 ′), with the latter being perfectly retained and placed inside part ( 2 ) as shown clearly in FIG. 2 .
Additionally, contacts ( 3 ) and ( 3 ′) have arced projections ( 17 ) and ( 18 ) which have a configuration and arrangement such that they form pairs of contacts which, depending on the position adopted by jack plug ( 4 ), will contact the inner ends ( 12 ) of pins ( 10 ) of said plug ( 4 ), so that when these inner elements ( 12 ) of the of the plug rest on projections ( 18 ) of contacts ( 3 ) and ( 3 ′), the plug will provide electrical continuity to the device, in adopting a horizontal position, while if the plug ( 4 ) is rotated 90° from such position the inner ends ( 12 ) of pins ( 11 ) of plug ( 4 ) will contact projections ( 18 ), also establishing electrical continuity, and thus the device may be operated in these two positions of the plug ( 4 ), that is, both horizontal and vertical, and thereby adapt to any type of socket currently commercialized.
However, if plug ( 4 ) is placed by rotation about casing ( 1 ) in a position in between the two above described positions, that is at an angle of 45° to them, the ends ( 12 ) of said plug ( 4 ) will be opposite segments ( 19 ) located between projections ( 17 ) and ( 18 ), which segments ( 19 ) are in an inner or more recessed plane, and thus ends ( 12 ) will not reach contacts ( 3 ) and ( 3 ′), thereby attaining the deactivated position without requiring any type of switch.
Naturally, contacts ( 3 ) and ( 3 ′) will be connected to the corresponding electrical resistors ( 20 ) which may be secured by zero, one or two clips ( 21 ), and whose excess wire ( 22 ) by which the corresponding connections are performed are pushed by this special configuration of bridges ( 14 ) and tabs ( 15 ) of contacts ( 3 ) and ( 3 ′) against grooves ( 23 ) provided for such purpose in walls ( 16 ) for mounting contacts ( 3 ) and ( 3 ′), so that these ends of excess wire ( 22 ) of resistors ( 20 ) are folded and straightened in the position corresponding to grooves or slots ( 23 ).
As regards the inner part ( 2 ), in addition to the already described characteristics it is provided with a corresponding passage neck ( 24 ) for placing the wick of the vessel which contains the active substance, which must be mounted on the bottom of the device unit, with said part ( 2 ) secured to the inside of casing ( 1 ) by pins ( 25 ) placed on the inner or top end of part ( 2 ) and which lock inside casing ( 1 ), thereby securing it without the possibility of extraction without breaking the unit.
Lastly, said part ( 2 ) is provided in its bottom end with an elastic ring ( 26 ), oval in shape, between whose proximal or lateral sides is retained, by its neck, the vessel containing the substance to be evaporated, and in which vessel is naturally provided a wick which emerges upwards through a passing neck ( 24 ) of part ( 2 ), so that this wick is heated by resistances ( 20 ) located around it, causing its heating and thereby the evaporation of the liquid or substance which by capillary action rises to the top of the wick placed as mentioned above. In order to release the vessel from ring ( 26 ) it suffices to press inwards from the outside on elastic sector ( 7 ) of casing ( 1 ), which pressure involves the inwards deformation of sector ( 7 ) and thereby pushes on segment ( 26 ′) of ring ( 26 ), separating the sides of the ring and thereby releasing the vessel. | A heater device includes an external casing ( 1 ), an inner part ( 2 ), a pair of contact elements ( 3 ) and ( 3′ ), and a jack plug ( 4 ). Contact elements ( 3 ) and ( 3′ ) define pairs of salient projections ( 17 ) and ( 18 ) which allow connection of the jack plug ( 4 ) in two positions of rotation, at 90° to each other, and prevent connection in an intermediate position. The heater device operates to heat a wick which emerges from a vessel containing an active substance to cause the evaporation of the substance. The vessel is retained on the lower end of the heather device by a ring ( 26 ) provided on inner part ( 2 ). | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to compounds which have excellent insecticidal and acaricidal activities to various insect pests in sanitation as well as agriculture, horticulture and forest.
2. Description of the Prior Art
Recently, structure modifications of natural pyrethrin have been widely studied and various pyrethroids have been developed and used as insecticides. Even today, there is a demand for development of new chemicals having more excellent insecticidal and acaricidal characteristics.
The inventors have studied the syntheses and biochemical activities of various compounds in the development of compounds having insecticidal and acaricidal activities which are superior to the known compounds.
Heretofore, it has been known that certain cyano(6-phenoxy-2-pyridyl) methyl esters of carboxylic acids such as 2,2-dimethyl-3-dichlorovinyl-cyclopropane carboxylic acid (Japanese Unexamined Patent Publication No. 112881/1978) or α-isopropyl-p-chlorophenyl acetic acid (Japanese Unexamined Patent Publication No. 115869/1980 or U.S. Pat. No. 4,228,172) have an insecticidal activity.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide insecticidal and acaricidal compounds which have high insecticidal and acaricidal effects and low toxicity to mammals and fishes.
Briefly, the foregoing and other objects of the present invention have been attained by providing insecticidal and acaricidal compounds of fluorine substituted pyridine methyl esters having the formula ##STR3## wherein R represents ##STR4## in which X is chlorine or difluoromethoxy; Y is chlorine or tert-butyl; and Z is a halogen atom.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The novel compounds of fluorine substituted pyridine methyl esters having the formula (I) have excellent insecticidal and acaricidal effect. As described in the following examples the insecticidal and acaricidal activity of the compounds of the present invention is significantly superior to that of the known compounds which have a similar structure.
It is an unexpected result from the conventional knowledge that the compounds of the present invention have excellent insecticidal and acaricidal activity.
The process for producing these compounds will be illustrated by the following schemes (A) to (D). ##STR5##
In the schemes (A) to (D), R is as defined above and Hal represents a halogen atom and W represents a halogen atom or a sulfonate group and M represents sodium or potassium.
The processes are further illustrated in detail as follows.
In the process (A), an organic tertiary base such as pyridine and triethylamine or an inorganic base such as alkali metal or alkaline earth metal hydroxides is used as the dihydrogen halide agent and the starting materials are reacted in an inert solvent such as benzene.
In the process (B), the starting components are reacted in an inert solvent such as acetonitrile in the presence of a dehydrating agent such as dicyclohexylcarbodiimide. Alternatively, p-toluenesulfonic acid or conc. sulfuric acid used in an esterification can be used as the catalyst.
In the process (C), the starting materials are reacted in a solvent such as dimethylformamide, preferably under refluxing. In the course of the reaction, an alkali metal or alkaline earth metal hydroxide is used for converting an acid to a salt such as potassium or sodium salt etc.
In the process (D), the starting materials are reacted in an aprotic solvent which is not miscible to water such as n-heptane in the presence of water soluble cyan compound such as sodium cyanate and a phase transfer catalyst such as tetra-n-butyl ammonium chloride or trimethyl benzylammonium chloride to obtain the compound of the present invention in high yield.
The starting materials, cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl alcohol and 5-fluoro-6-phenoxy picolinic aldehyde, used in the schemes (A) to (D), are novel compounds which can be prepared according to the following reaction scheme (E). ##STR6##
A diazonium salt is formed by reacting 2-chloro-5-amino- 6-phenoxypyridine with butyl nitrite in the presence of HPF 6 and is decomposed by heating (Baltz-Schiemann reaction) to obtain 2-chloro-5-fluoro-6-phenoxypyridine. The obtained product is reacted with magnesium and then with a formylating agent such as dimethylformamide to obtain 5-fluoro-6-phenoxy picolinic aldehyde. In the case where cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl alcohol is required, it is prepared by reacting the aldehyde with sodiumbisulfite and then with a cyanide compound such as sodium cyanide.
The typical esters of the present invention are given in Table 1.
TABLE 1______________________________________ ##STR7## (I) RefractiveCompound No. R index (n.sub.D.sup.20)______________________________________ ##STR8## 1.5464 2 ##STR9## 1.5329 3 ##STR10## 1.5648 4 ##STR11## 1.5430 5 ##STR12## 1.5600 6 ##STR13## 1.5816 7 ##STR14## 1.5660______________________________________
The serial numbers of the compounds given in Table 1 are referred in the following examples of Preparations, Compositions and Tests.
The esters of the present invention, of course, include optical isomers thereof due to the asymmetric carbon atom at the carboxylic acid moiety and at the alcohol moiety, and geometrical isomers thereof due to the stereochemical structure in some carboxylic acid moieties.
The compounds of the present invention are useful as insecticides for controlling insect pests in sanitation, and various insect pests in agriculture and horticulture which cause damages to rice, vegetable, fruits, cotton, and other crop plants and flowers and insect pests in forest and insect pests in storages.
The typical insect pests which are controlled by the compounds of the present invention are provided for purposes of illustration only.
______________________________________OrthopteraGerman Cockroach (Blattella germanica)Rice Grasshopper (Oxya yezoensis)ThysanopteraRice Thrips (Baliothrips biformis)HemipteraRice Stink Bug (Lagynotomus elongatus)Green Stink Bug (Nezcra antennata)Rice Bug (Leptocorisa chinensis)Bean Bug (Riotortus clavatus)Cotton Bug (Dysdercus cingulatus)Grape Leafhopper (Epiacanthus stramineus)Green Rice Leafhopper (Nephotettix cincticeps)Small Brown Planthopper (Laodelphax striatellus)Brown Rice Planthopper (Nilaparvata lugens)White-backed Rice Planthopper (Sogatella furcifera)Citrus Psylla (Diaphorina citri)Greenhouse Whitefly (Trialeurodes vaporariorum)Cowpea Aphid (Aphis craccivora)Cotton Aphid (Aphis gossypii)Apple Aphid (Aphis spiraecola)Green Peach Aphid (Myzue persicae)Citrus Mealybug (Planococcus citri)Comstock Mealybug (Pseudcoccus censtocki)Red Scale (Aonidiella aurantri)San Jose Scale (Comstockaspis perniciosa)Arrowhead Scale (Unaspis yanonensis)LepidopteraApple Leafminer ((Phyllonorycfer ringoneella)Citrus Leafminer (Phyllocnistis citrella)Diamondback Moth (Plutella xylostella)Pink Bollworm (Pectinophora gossypiella)Potato Tuberworm (Phthorimaea operculella)Peach Fruit Moth (Carposina niponensis)Summer Fruit Tortrix (Adoxophyes orana)Oriental Fruit Moth (Grapholita molesta)Soybean Pod Borer (Leguminivora glycinivorella)Rice Stem Borer (Chila suppressalis)Rice Leafroller (Chaphalocrocis medinalis)Pea Pod Borer (Etiella zinckenella)Oriental Corn Borer (Ostrinia furnacalis)Yellow Rice Borer (Tryporyza incertulas)Cutworm (Agrotis segetum)Cotton Looper (Anomis flava)American Bollworm, Cotton (Heliothis armigera, H. zeaBollworm or Tabacco H. virescens)BudwormCabbage armyworm (Mamestra brassicae)Beet Semi Looper (Plusia nigrisigna)Rice Armyworm (Pseudaletia separata)Pink Borer (Sesamia inferens)Common Cutworm (Spodoptcra litura)Common White (Pieris rapae crucivora)Smaller Citrus Dog (Papilio xuthus)Rice Skipper (Parnara guttata)Codling Moth (Cydia pomonella)ColeopteraCupreous Chafer (Anomala cuprea)Asiatic Garden Beetle (Maladera castanea)Japanese Beetle (Popillia Japonica)Twenty-eight-spotted (HenosepilachnaLady beetle vigintioctopunctata)Cucurbit Leaf Beetle (Aulacophora femoralis)Rice Leaf Beetle (Oulema oryzae)Striped Flea Beetle (Phyllotreta striolata)Rice Plant Weevil (Echinocnemus squameus)Rice Water Weevil (Lissorhoptrus oryzophilus)Vegetable Weevil (Listroderes obliquus)Maize Weevil (Sitophilus zeamais)Bull Weevil (Anthonomus grandis)Corn Rootworms ( Diabrotic spp.)Colorado Potato Beetle (Leptinotarsa decemlineata)HymenopteraFire Ant (Solenopsis geminata)DipteraSoybean Pud Gall Midge ( Asphondylia spp.)Oriental Fruit Fly (Dacus dorsalis)Rice Leafminer (Hydrellia griseola)Rice Stem Maggot (Chlorops oryzae)Rice Leafminer (Agromyza oryzae)Seedcorn Maggot (Hylemya platura)Mediterranean Fruit Fly (Ceratitis capitata)Rice Gall Midge (Orseolia oryzae)House Fly (Musca domestica)Pale House Mosquito (Culex pipiens pallens)IsopteraTermites (Coptotermes formosanus)______________________________________
The insecticidal activity of the compounds of the present invention is imparted not only two young larva but also to old larva directly or in penetration by direct contact or immersion. The compounds of the present invention are also effective to control various acarinas and nematodes.
In the application of the insecticidal composition of the present invention, it is preferable to apply it at a concentration of 0.01 to 10,000 ppm preferably 0.1 to 2,000 ppm of the active ingredient. In order to control aquatic insect pests, the composition having said concentration can be sprayed to the part to control the aquatic insect pests. Therefore, the concentration of the active ingredient in water can be lower.
In the application of the compound of the present invention as the insecticide, it is preferable to prepare a composition by mixing the active ingredient with a desired solid carrier such as clay, talc and bentonite; or a liquid carrier such as water, alcohols (methanol, ethanol etc.), ketones, ethers, aliphatic hydrocarbons, aromatic hydrocarbons (benzene, toluene, xylene etc.), esters and nitriles, if necessary, with an emulsifier, a dispersing agent, a suspending agent, a spreader, a penetrant and a stabilizer so as to form suitable compositions for practical applications in the form of an emulsifiable concentrate, an oil spray, a wettable powder, a dust, a granule, a tablet, a paste, a flowable, a bait poison, an aerosol, a fumigrant, a mosquito-coil and mosquito mat.
It is possible to blend the active ingredient of the present invention to a suitable other active ingredient such as the other insecticides, germicides, herbicides, plant growth regulators, and fertilizers in the preparation of the composition or in the application.
The present invention will be further illustrated by certain Reference examples, examples of Preparations, Compositions and Tests which are provided for purposes of illustration only and are not intended to be limiting the present invention.
REFERENCE EXAMPLE 1
Preparation of 5-fluoro-6-phenoxy picolinic aldehyde as the starting material
Dissolved in 160 ml of ethylalcohol were 45 g of 2-chloro-5-amino-6-phenoxypyridine (prepared by a known method as disclosed in West German Offenlegenschrift 2022024) and 130 g of HPF 6 . While cooling this mixed solution at -10° C., 28 g of butyl nitrite was added dropwise. After the reaction, the formed precipitate was collected by filtration, and washed with ethyl ether until the filtrate became colourless. The crystals thereby obtained were dried in vacuum at 50° C. for 8 hours to obtain 65 g of a product. This compound was transferred to a reaction flask, and gradually heated by means of a burner. Gradual decomposition with generation of a white smoke was observed. After the decomposition, an aqueous potassium carbonate solution was added for neutralization, and then 100 ml of chloroform was added for extraction to obtain a crude product.
The crude product was subjected to alumina column chromatography (developer: benzene) to remove coloured substances, and then distilled under reduced pressure to obtain 12.6 g of 2-chloro-5-fluoro-6-phenoxypyridine having a boiling point of 102° to 105° C./0.3 mmHg. The structure of this compound was confirmed by the nuclear magnetic resonance absorption spectra.
To a reaction flask(300 ml)equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel and a nitrogen supply tube, 1.45 g (0.06 gram-atom) of magnesium was introduced. Added thereto was 10 ml of dried tetrahydrofuran, and the air was replaced by nitrogen, and thereafter, nitrogen was continuously supplied from the nitrogen supply tube. Dissolved in tetrahydrofuran was 11.2 g (0.05 mole) of 2-chloro-5-fluoro-6-phenoxypyridine to obtain 100 ml of a solution, and a 1/10 amount (i.e. 10 ml) thereof was added to the reaction flask. The reaction flask was dipped in an oil bath to bring the temperature to from 35° to 40° C. After the initiation of the reaction, the remaining 9/10 amount (i.e. 90 ml) of the tetrahydrofuran solution was added dropwise while stirring to avoid a vigorous reaction. After the addition, the stirring was continued at 40° C. for further 30 minutes. Then, the reaction flask was immersed in an ice/water bath (0° C.) to cool it down, and then 4.4 g (0.06 moles) of dimethylformamide was added dropwise in 10 minutes. The mixture was stirred for 30 minutes at 40° C. After cooling, the tetrahydrofuran was distilled off under reduced pressure, and the residue was added to 10 ml of concentrated hydrochloric acid and 100 g of ice, thereby decomposing the remaining magnesium, and then neutralized with an aqueous solution of 1N sodium hydroxide to bring the pH to 7 to 8. The solution was transferred to a separating funnel, and after adding 100 ml of ethyl ether, it was adequately shaken. After washing the organic layer with a saturated aqueous sodium chloride solution and water, the organic layer was dried over anhydrous sodium sulfate, and the ethyl ether was distilled off under reduced pressure to obtain a crude product. This crude product was found to contain the desired 5-fluoro-6-phenoxy picolinic aldehyde (retention time 4.1 minutes) and the starting material 2-chloro-5-fluoro-6-phenoxypyridine in a proportion of 3:2, by the gas chromatography (Silicone DCHV 15%/Chromosorb WAW, 60 to 80 mesh, 1 m, the temperature rise from 150° C. at a rate of 20° C./min.).
Then, this crude product was purified by silica gel column chromatography (WAKO GEL Q-23 (trade name) which is available from Wako Chemical Corporation, 100 to 200 mesh, diameter of 4 cm×length of 42 cm, developer: benzene, an eluate of from 2000 ml to 2500 ml was collected), whereupon 3.1 g of the desired 5-fluoro-6-phenoxy picolinic aldehyde was obtained. The melting point was 66.0° to 71.0° C.
The structure of this product was confirmed by the nuclear magnetic resonance absorption spectra (CDCl 3 , δ, ppm; 6.80 to 7.95 (7H, m), 9.64 (1H, s)) and the mass spectrography (m/z; 217 (M + ) and 188 (M + --CHO)).
REFERENCE EXAMPLE 2
Preparation of cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl alcohol as the starting material
A mixture of 2.2 g of 5-fluoro-6-phenoxy picolinic aldehyde and 1.1 g of sodiumbisulfite was stirred vigorously in 10 ml of water until the mixture formed an emulsion. The resulting solution was extracted with 10 ml of ether. To the aqueous layer were added 0.54 g of sodium cyanide and 5 ml of water. After being stirred for 30 minutes, the reaction mixture was extracted with 20 ml of ether. The organic layer was dried over anhydrous sodium sulfate and concentrated to give 2.2 g of cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl alcohol. The structure of this product was confirmed by the nuclear magnetic resonance absorption spectra (CDCl 3 , δ, ppm; 4.20 (1H, bs), 5.34 (1H, s), 7.00-7.80 (7H, m)).
PREPARATION 1
Cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl α-isopropyl-p-chlorophenyl acetate (Compount No. 1)
Into 20 ml of benzene, 2.4 g of cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl alcohol and 0.8 g of pyridine were dissolved. The solution was stirred under cooling with ice and 2.3 g of α-isopropyl-p-chlorophenyl acetic acid chloride was added dropwise to the solution. After reacting them for 1 hour, the reaction product was washed twice with 10 ml of water and the organic layer was dried over anhydrous sodium sulfate and benzene was distilled off under a reduced pressure. The residual oily product was purified by a column chromatography (alumina; developing solvent: benzene)to obtain 4.1 g of the object compound. n D 20 1.5464. NMR spectrum: δ, ppm, CDCl 3 ;
0.70 (3H, d, J=6.0 Hz), 0.90 (1.5H, d, J=6.0 Hz) 0.98 (1.5H, d, J=6.0 Hz), 2.30 (1H, m), 3.18 (0.5H, d, J=10.0 Hz), 3.20 (0.5H, d, J=10.0 Hz), 6.17 (1H, bs), 6.95-7.65 (11H, m)
PREPARATION 2
Cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl trans-2,2-dimethyl-3-(p-t-butylphenyl)cyclopropanecarboxylate (Compound No. 4)
Into 20 ml of n-hexane, 2.2 g of 5-fluoro-6-phenoxy picolinic aldehyde, 2.7 g of trans-2,2-dimethyl-3-(p-tert-butylphenyl)cyclopropanecarboxylic acid chloride, 0.6 g of sodium cyanide, 1 ml of water and 0.1 g of tetra-n-butylammonium chloride were added.
The mixture was vigorously stirred at room temperature to react them for 30 hours. After the reaction, the organic layer was washed with 10 ml of water and dried over anhydrous sodium sulfate and n-hexane was distilled off under a reduced pressure. The residual crude product was purified by a column chromatography (alumina; developing solvent: benzene) to obtain 3.8 g of the object compound. n D 20 1.5430.
NMR spectrum: δ, ppm, CDCl 3 ; 0.98 (3H, bs), 1.28 (1.5H, s), 1.30 (9H, s), 1.39 (1.5H, s), 2.05 (1H, m), 2.70 (1H, m), 6.30 (1H, m), 6.90-7.70 (m, 11H)
PREPARATION 3
Cyano(5-fluoro-6-phenoxy-2-pyridyl) methyl (1R, cis)-2,2-dimethyl-3-(2,2-dibromovinyl)cyclopropane carboxylate (Compound No. 6)
Into 20 ml of hexane, 3.2 g of acid chloride (prepared from (1R, cis)-2,2-dimethyl-3-(2,2-dibromovinyl)cyclopropane carboxylic acid ([α] D 20 +26.3 (C=0.81, C 6 H 6 )) and thionyl chloride), 2.2 g of 5-fluoro-6-phenoxy picolinic aldehyde, 0.6 g of sodium cyanide, 1 ml of water and 0.1 g of tetrabutylammonium chloride were added. The mixture was vigorously stirred at room temperature to react them for 24 hours. After the reaction, 50 ml of ethyl ether and 20 ml of water were added. The organic layer was washed with 10 ml of water and dried over anhydrous sodium sulfate and n-hexane was distilled off to obtain a crude ester. The crude ester was purified by a column chromatography (alumina; developing solvent: benzene) to obtain 4.5 g of the object compound. n D 20 1.5816.
[α] D 20 +7.85 (C=0.48, C 6 H 6 ) and [α] D 20 +9.52 (C=0.52, CHCl 3 ).
NMR spectrum: δ, ppm, CDCl 3 ; 1.25 (6H, bs), 2.10 (2H, m), 6.24 (1H, s), 6.66 (1H, d, J=7.0 Hz), 6.80-7.75 (7H, m).
Certain examples of the compositions of the compounds of the present invention as insecticides are provided for purposes of illustration only and are not intended to be limiting the present invention.
______________________________________Composition 1 Emulsifiable concentrate:Active ingredient______________________________________Compound No. 1: 10 wt. partsXylene: 80 wt. partsSorpol 2680 (Toho Chem.): 10 wt. parts______________________________________
The components were uniformly mixed to prepare an emulsifiable concentrate. The emulsifiable concentrate was diluted with water to 50-100,000 times and it was sprayed in amounts of 10-500 liter/10 ares.
As the active ingredient, other compounds in Table 1 were also used.
______________________________________Composition 2 Oil solution:Active ingredient______________________________________Compound No. 1: 50 wt. partsMethyl cellosolve: 50 wt. parts______________________________________
The components were uniformly mixed to obtain an oily solution.
The oil solution was applied in amounts of 0.1 to 50 ml/m 2 to a drain or puddle or in amounts of 10-100 ml/10 ares by airplain spray. As the active ingredient, other compounds in Table 1 were also used.
______________________________________Composition 3 Wettable powder:Active ingredient______________________________________Compound No. 4: 25 wt. partsZeeklite PFP: 65 wt. partsCarplex #80: 2 wt. partsSorpol 5050: 2 wt. partsSodium ligninesulfonate: 6 wt. parts______________________________________
The components were uniformly ground and mixed to obtain a wettable powder. The wettable powder was diluted with 100 to 250,000 times of water and it was sprayed in amounts of 20 to 500 liter/10 ares.
As the active ingredient, other compounds in Table 1 were also used.
______________________________________Composition 4 Dust:Active ingredient______________________________________Compound No. 6: 3.0 wt. partsCarplex #80: 0.5 wt. partsClay: 95 wt. partsDiisopropyl phosphate: 1.5 wt. parts______________________________________
The components were uniformly mixed to obtain a dust. The dust was applied in amounts of 0.03 to 15 kg/10 ares.
As the active ingredient, other compounds in Table 1 were also used.
The insecticidal activities of the compounds of the present invention are illustrated by the following tests.
As references, the following active ingredients were used. ##STR15##
EXPERIMENT 1
Contact test for killing green rice leafhopper
Stems and leaves of a rice seedling were dipped in each emulsion of each active ingredient of the present invention or a reference compound for 10 seconds and were dried in air. The stems and leaves were covered with a glass cylinder. Adult green rice leafhoppers which are resistant to the conventional organic phosphorus type insecticide were released into the glass cylinder which was covered with a cover having holes and was maintained in a constant temperature room at 25° C. for 48 hours and each percent mortality was determined and median lethal dose (LC 50 ) was calculated in Finny's graphic method.
The results are shown in Table 2.
TABLE 2______________________________________Active ingredient LC.sub.50 (ppm)______________________________________Compound No. 1 0.26Reference Compd. A 1.4Reference Compd. B 5.0Compound No. 2 0.28Reference Compd. C 76.0Reference Compd. D 6.0Compound No. 3 0.7Reference Compd. E 16.0Compound No. 4 1.3Reference Compd. G 32.0Reference Compd. H 6.4Compound No. 5 0.40Compound No. 6 0.31Reference Compd. I 3.7______________________________________
EXPERIMENT 2
Contact test for killing Common cutworm
Leaves of cabbage were dipped in each aqueous emulsion of each active ingredient of the compounds of the invention or the reference for 10 seconds. The leaves were taken up and dried in air and put in a Petri dish. Common cutworms (second instar) were put in the Petri dish which was covered with a cover having many holes. The Petri dish was maintained in a constant temperature room at 25° C. for 48 hours and each percent mortality was determined and median lethal dose (LC 50 ) was calculated in Finny's graphic method.
The results are shown in Table 3.
TABLE 3______________________________________Active ingredient LC.sub.50 (ppm)______________________________________Compound No. 1 0.43Reference Compd. A 3.1Reference Compd. B 1.7Compound No. 2 3.0Reference Compd. C 5.0Reference Compd. D 9.0Compound No. 3 1.3Reference Compd. E 13.0Reference Compd. F 15.0Compound No. 4 4.0Reference Compd. G 12.0Compound No. 5 0.31Compound No. 6 0.24Reference Compd. I 10.0______________________________________
EXPERIMENT 3
Test for killing Green peach aphid
Each emulsifiable concentrate of the compound of the present invention or the reference compound was diluted with water to a predetermined concentration. Green peach aphid were inoculated on leaves in a Petri dish having a diameter of 3 cm and 2 ml of each emulsion was sprayed and it was covered. The Petri dish was maintained in a constant temperature room at 25° C. for 48 hours and each percent of mortality was determined and median lethal dose (LC 50 ) was calculated in Finny's graphic method.
The results are shown in Table 4.
TABLE 4______________________________________Active ingredient LC.sub.50 (ppm)______________________________________Compound No. 2 2.3Reference Compd. D 26.0Compound No. 4 4.6Reference Compd. H 12.0Compound No. 5 1.84Reference Compd. I 34.0______________________________________
EXPERIMENT 4
Test for killing Kanzawa spider mite
Leaves of kidney bean was cut by a leaf-punch in a form of circle having a diameter of 1.5 cm. The leaf-discs were put on a wet filter paper on a polystyrene cup having a diameter of 7 cm. Ten of Kanzawa spider mites were inoculated on the leaf-discs in the cup. Half days after the inoculation, each solution prepared by diluting each emulsifiable concentrate of the present invention or each reference compound with a spreader (Nitten S 4,000 times manufactured by Nissan Chem.) at each predetermined concentration was sprayed by a rotary spray for 2 ml. per each cup.
Numbers of mortalities of mites were measured after 48 hours from the spraying and percent mortaliteis were calculated and median lethal dose (LC 50 ) was calculated in Finny's graphic method.
The results are shown in Table 5.
TABLE 5______________________________________Active ingredient LC.sub.50 (ppm)______________________________________Compound No. 1 6.3Reference Compd. A 100Compound No. 2 12Reference Compd. C >100Compound No. 4 0.32Reference Compd. G 2.0Compound No. 5 5.4Reference Compd. I >100______________________________________
EXPERIMENT 5
Contact test for killing Twenty-eight-spotted Ladybeetle
Leaves of tomato were dipped in each emulsion of each active ingredient of the present invention or the reference for 10 seconds. The leaves were taken up and dired in air and put in a Petri dish. Ten of Twenty-eight-spotted Ladybeetles (second instar) were put in the Petri dish which was covered with a cover. The Petri dish was maintained in a constant temperature room at 25° C. for 48 hours and percent mortality was determined and median lethal dose (LC 50 ) was calculated in Finny's graphic method.
The results are shown in Table 6.
TABLE 6______________________________________Active ingredient LC.sub.50 (ppm)______________________________________Compound No. 1 0.05Compound No. 2 0.5Reference Compd. C 21.0Reference Compd. D 0.9Compound No. 3 0.26Reference Compd. F 2.0Compound No. 5 0.03Compound No. 6 0.02______________________________________ | Fluorine substituted pyridine methyl esters having the formula ##STR1## wherein R represents ##STR2## in which X is chlorine or difluoromethoxy; Y is chlorine or tert-butyl; and Z is a halogen atom, are novel compounds which are useful as insecticides and acaricides. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a new and improved window replacement system for use in remodeling existing buildings and the like wherein the old windows have deteriorated and must be replaced.
2. Description of the Prior Art
Many old buildings exist which are structurally sound and which have ideal locations but which are economically disadvantaged because of the deteriorated condition of the windows and the excessive heat losses and undesirable side effects caused thereby. Because of the increasing energy costs, in order to make the remodeling of a building economically feasible, it is desirable to replace old deteriorated windows therein to reduce energy costs.
Specifically, replacement usually begins by removal of the old window sashes while leaving an existing frame of metal or wood and the outer trim in tact. New windows preferably of the double glazed and heat insulating type, are then installed in the window openings and various types of trim members are thereafter secured in place and sealed around between the peripheral edges of a new replacement window frame and the adjacent edges of the old window opening.
Because such a great variety exists in types of windows, trim and frame arrangements in existing buildings sought to be remodeled and updated for energy corrections, an approach to the problem has not been feasible or realized in the prior art. Moreover, the task of installing tight sealing and nice looking trim elements around a newly installed replacement window has been difficult and costly with often times undesirable consequences such as unsightly appearance and weather leakage.
OBJECTS OF THE PRESENT INVENTION
It is an object of the present invention to provide a new and improved replacement window system for use in existing buildings and more particularly, it is an object of the present invention to provide a new and improved replacement window system wherein trim elements are installed around the peripheral edges of the replacement windows before the installation or mounting of these windows in the openings in an existing building from which openings, the old and/or deteriorated windows have been removed.
Another object of the present invention is to provide a new and improved replacement window system of the character described suitable for use wherein old and/or deteriorated window sashes are removed from an existing building leaving an existing outer window frame and trim intact.
It is another object of the invention to provide a new and improved replacement window system of the character described which includes a replacement window with peripheral trim elements attached and sealed therewith adapted to be mounted in a window opening of an existing building structure having outer window frame and/or trim elements therein covered by the new window trim.
Another object of the present invention is to provide a new and improved method of replacing the deteriorated and/or windows in an existing building with new windows having improved operating characteristics.
Yet another object of the present invention is to provide a new and improved replacement window system employing a novel design for trim element which is easily cut to length and installed on a replacement window frame prior to mounting of the interior frame into an existing opening from which a window to be replaced had been removed.
Still another object of the present invention is to provide a new and improved replacement window system wherein the difficulty of sealing between the replacement window trim elements and the existing wall structure is minimized.
Still another object of the present invention is to provide a new and improved replacement window system wherein a replacement window with a peripheral trim is provided to easily fit into an existing window opening to cover the old trim and/or frame elements of a window that has been removed.
Yet another object of the present invention is to provide a new and improved elongated trim element for use with a replacement window adapted to be pivotally interconnected and sealed against an outer edge portion of the window frame.
Still another object of the present invention is to provide a new and improved trim element for use with a replacement window and adapted to seal around and cover an existing frame and/or trim elements left in place in a building wall structure.
Still another object of the present invention is to provide a new and improved elongated trim element which is especially adapted to interfit around the outer periphery of a replacement window frame and which is readily installed to form a complete peripheral trim around the window for sealing between the window and the surround of an existing window opening.
Still another object of the present invention is to provide a new and improved replacement window system wherein a novel mounting support element is included for rapidly installing and securing a replacement window in an existing window opening.
Still another object of the present invention is to provide a new and improved replacement window system of the character described wherein elongated interior trim elements are provided to interfit and trim around the periphery of the replacement window on the interior side thereof.
Still another object of the present invention is to provide a new and improved replacement window system wherein elongated interior trim elements are provided to snappingly interfit with window supporting elements on the interior side of a replacement window mounted in an existing window opening.
Another object of the present invention is to provide a new and improved replacement window system which permits the original window frame and trim to remain in place for aid in support of a replacement window.
BRIEF SUMMARY OF THE INVENTION
The foregoing and other objects and advantages of the present invention are accomplished in an illustrated embodiment comprising a new and improved replacement window system for installing a replacement window in the opening of an existing building wall structure, from which opening an old or deteriorated window has been removed. The new and improved system includes apparatus for trimming around the periphery on the outside of a replacement window and the trim apparatus includes elongated exterior trim elements having a flange adapted to extend outwardly of a side frame member of the window and an integral fascia portion joining the flange and extending between the flange and an adjacent edge of the opening in the wall that the replacement window is to be mounted in. The exterior trim elements are provided with elongated connector means along an inner edge of the flange for providing a continuous pivotal interlock between the side frame member of the replacement window and the trim element.
In accordance with the method of the present invention, the replacement window is initially trimmed before installation with a plurality of elongated exterior trim elements mounted thereon to form a complete trim frame around the periphery of the window. Weathertight sealing is effected between the trim elements and the window before the window with the attached trim is mounted in place in an existing opening of a building wall structure. The installation of the window is rapid and easy by using clip elements on the inside attached between the window frame and the existing frame of the old window that has been removed. A final peripheral seal is then completed around the exterior trim element and the wall finally, interior trim elements are mounted around the periphery of the replacement window after it is secured in position in the window opening.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference should be had to the following detailed description taken in conjunction with the drawings, in which:
FIG. 1 is an outside elevational view of an existing building wall structure having a plurality of window openings therein and illustrating in somewhat animated fashion the method of the present invention wherein a deteriorated and/or old window is removed leaving intact a peripheral frame or trim element followed by the installation of a replacement window and trim system in accordance with the features of the present invention;
FIG. 2 is an enlarged, fragmentary, horizontal cross-sectional view taken substantially along lines 2--2 of FIG. 1;
FIG. 3 is an enlarged, fragmentary, cross-sectional view taken substantially along lines 3--3 of FIG. 1;
FIG. 4 is an enlarged, fragmentary, cross-sectional view similar to FIG. 2 but illustrating in somewhat animated form a pivotal interconnection between a replacement window frame edge and an elongated trim element in accordance with the features of the present invention;
FIG. 5 is a greatly enlarged, fragmentary, horizontal cross-sectional view similar to FIG. 4 but illustrating in enlarged detail the pivotal interlock between the elongated trim element and the window frame member in accordance with the features of the present invention;
FIG. 6 is a fragmentary, enlarged, exploded perspective view of a lower corner portion of the window replacement system of the present invention as seen from the inside;
FIG. 7 is a fragmentary, enlarged, perspective view of a lower corner section of the window replacement system of the present invention as seen while looking outwardly from the inside of a building in which the replacement window and trim system has been installed; and
FIG. 8 is a greatly, enlarged, fragmentary cross-sectional view taken substantially along lines 8--8 of FIG. 7 and illustrating a mounting clip element in a position ready for permanent attachment to the adjacent window frame member.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more particularly to the drawings, in FIG. 1 is illustrated an elevational view of a wall structure of an existing building referred to generally by the numeral 10. The existing wall structure is formed with a plurality of rectangularly shaped window openings 12a, 12b and 12c, respectively, left to right, and the left-hand window opening 12a is illustrated with an old and/or deteriorating, double hung, wood window 14 mounted therein which is to be replaced with a new, preferably heat insulating and modern type, replacement aluminum frame window such as a window 16, shown mounted in the right-hand window opening 12c of the wall.
In accordance with the present invention, an upper and lower sash 14a and 14b of the old deteriorating window 14 are removed for replacement and preferably, the rectangular supporting framework of the old window comprising a pair of vertical jambs 18, an upper header 20 and an outwardly and downwardly sloping lower sill 22 are left intact in place in the window opening. A pair of outside vertical jamb stops 24, a header stop 26 and a pair of outside brick or trim molding elements 28 adjacent the vertical jambs and a header brick molding 30 adjacent the header 20 are also left in place. In addition, a pair of vertical inside, jamb stops 32 and an inside header stop 34 and inside window sill member 36 may also be left intact in place after the old window sashes 14a and 14b have been removed. This arrangement provides for a rapid and fast conversion or remodeling process in that only the window sash and intermediate stops need be removed.
Preferably, the replacement window 16 is of a modern, heat insulating, aluminum frame type adapted to hold a single pane of double thickness insulating glass or one or more removable or openable operating sashes preferably of the type having insulating type glazing. The support frame of the replacement window is of a generally rectangular shape having a width and height dimension slightly less than the distance or width measurement between the opposite jamb stops 24 and a height distance measurement slightly less than the vertical or height distance between the upper header stop 26 and the sill 22 of the old window frame. If the old window frame and trim members are removed along with the old window sashes 14a and 14b, the size of the new replacement window 16 may be increased slightly if desired.
The rectangular frame of the new or replacement window 16 includes a pair of vertical stiles 38 interconnected adjacent the upper and lower ends by a pair of horizontally extending upper and lower rails 40 which are butt fitted against inside flange portions of the vertical stiles as shown. Preferably, both the stiles and the rails are identical in transverse cross-section and are of the heat insulating type including an outer face member 42 of extruded aluminum, an inner face member 44 of substantially identical cross-section and a continuous interconnecting structural insulating strip 46 between the outer and inner face members. The strip of insulating material 46 is of a cross-shaped transverse cross-section in keyed interconnection with opposite facing grooves provided in the metal face members.
The outer face members 42 of the window frame elements include an outer wall 42a and on the inside surface, spaced closely adjacent an outside edge, there is provided an elongated groove 43 which faces and is opposite to a similar groove 45 on an inside face portion 44a of the inner face member 44. The elongated continuous groove 43 provides for a positive, pivotal, interlocking interconnection between the window frame element and an elongated side trim element 50 of generally angle-shaped, transverse cross-section constructed in accordance with the features of the present invention. A pair of side or jamb trim elements 50 are provided on opposite sides of the window 16 and are generally similar in transverse cross-section to an elongated header trim element 60 and a sill trim element 70 which has a slightly different transverse cross-sectional shape.
In accordance with the present invention, the side trim elements 50 are formed of extruded aluminum and are cut to appropriate length to trim the window 16 from stock lengths of extruded material. The jamb trim element includes a flange portion 52 adapted to project outwardly at right angles to the outer wall 42a of the window frame member when the trim element is attached thereto. Along the inner edge, the flange 52 is formed with a continuous elongated grooved out portion 53 having a base wall 52a along the inside edge of the flange 52 at right angles to the main body portion thereof, a wall 52b generally parallel to the main body and an L-shaped rib 52c having a tongue 54 adapted to seat in the groove 43 of the window frame member. A sharp edged rib 56 is provided on the wall section 52a to engage the outer surface of the window frame wall face 42a as shown in FIGS. 4 and 5, when the trim element 50 is pivotally interlocked and removed into place with the flange 52 substantially at right angles to the wall surface 42a of the window frame member.
As best indicated in FIGS. 4 and 5, the side trim elements 50 are cut to length to run past the butt fitted ends of the upper, header trim element 60 and the lower, sill trim element 70 as illustrated. The side trim elements are attached to the stiles of the window frame by first engaging the tongue 54 within the elongated groove 43 and then pivoting the trim element in a counterclockwise direction as shown by the Arrow "A" in FIG. 4 until the main body of the flange 52 is substantially at right angles to the wall face 42a of the window frame member. In this position, the sharp edged tongue 54 stoppingly engages the outer surface of the window frame member 42a and limits further rotation in a counterclockwise direction. Rotation in the opposite clockwise direction, however, is permitted whenever it is desired to disassemble a side trim element 50 from a stile 38 of the window frame. The cooperating tongue 54 and groove 43 provide a continuous elongated, pivotal interconnection between the window frame and trim elements 50 and the rib 56 and wall 42a provide a limit stop as described so that assembly of the trim elements onto the sides of the window frame is easy and rapid.
The side trim elements 50 also include an outer fascia portion 58 at right angles to the flange portion 52 and generally in parallel with the outer surface wall 42a of the window frame. The fascia portions are adapted to bridge the space or opening between the side edge of the adjacent window frame member and the edge of an opening 12a, 12b, and 12c of the building wall and cover over the jamb elements 18, 24 and 28 of the old window frame which have been left in place after removal of the sash 14a and 14b. After a trimmed window 16 is mounted in a opening 12a, 12b, 12c, etc., a gunned-in bead of sealant or caulking material 59 is applied to provide sealing between an outer edge of the side trim element fascia 58 and the adjacent edge of the window opening in the building wall as shown in FIG. 2. This sealing is accomplished almost anytime after the window 16 with the trim element previously attached thereto has been mounted in place in the window opening of the building wall 10.
It should be noted that an inner edge of the fascia 58 projects inwardly toward the center of the window a slight distance beyond the perpendicular face of the flange 52 as shown in FIG. 2 in order to provide a small retaining rib 58a along the inside edge which aids in assembly of the header and sill trim elements 60 and 70 onto the frame of the window 16. It should also be noted that the flange 52 of the side trim elements 50 is coped away at the upper and lower corners at 55 and 57 in order to accommodate the upper brick molding 30 and the lower, existing sill 22 as shown in FIGS. 3 and 6. In addition, a pair of spaced apart holes 52d are drilled at appropriate upper and lower positions adjacent the coped corners to accommodate pairs of self-tapping fasteners 61 which are used for interconnecting the butt fitted ends of the horizontal trim elements 60 and 70 to the periphery of the window frame.
As indicated in FIG. 3, a pair of holes 52d are drilled in the flange 52 of the side trim elements 50 just below the coped out upper corner 55 in order to accommodate a pair of upper screw fasteners 61 while a similar pair of lower holes 52d as shown in FIG. 6, are drilled in the flange just above the upper level of the lower coped out portion 57 to accommodate the shanks of a pair of lower screw fasteners 61 used to attach the lower sill trim element 70 in butt fitted relation between the flanges 52 of the side trim elements 50.
In accordance with the present invention, the elongated, header trim element 60 is generally similar in transverse cross-section to the side trim elements 50 and includes a flange portion 62 adapted to extend outwardly of the outer face 42a of the upper header frame member of the replacement window 16 at right angles thereto. Along an inner edge, the flange portion 62 has a continuous groove 63 generally similar to the groove 53 and the groove is formed by a wall segment 62a parallel of the outer face member 42a, a segment 62b coextensive with the main body of the flange portion and an L-shaped or angular flange 62c having a tongue 64 adapted to inter-fit within the groove 43 on the wall face 42a of the upper header 40 of the frame of the window 16. A sharp edged tongue or stop 66 similar to the tongue 56 projects from the groove wall segment 62a to engage the outer face 42a of the window frame header and provide a pivot limiting stop engagement.
The flange 62a of the header trim element 60 is attached to the header rail 40 of the window frame in a manner similar to the pivotal, interlocking interconnection between the side trim elements 50 and the vertical stiles 38 of the window frame. As viewed in FIG. 3, after the tongue 64 is seated within the groove 43 in the window frame header 38, the header trim element 60 is then pivoted in a counterclockwise direction until the stop surface of a sharp edged tongue 66 engages the outer wall 42a of the window frame header to maintain the flange 62 normal to the wall and limit further rotation. In this position the flange 62 of the header trim element is substantially perpendicular or normal to the outer face of the window frame and transverse to the flanges 52 of the side trim elements 50. The header trim element 60 is cut to butt fitt between opposite facing flanges 52 of the side trim elements 50 and once in position therebetween, it is secured in place by the upper pair of threaded screw fasteners 61 which include threaded shanks driven through the upper pair of holes 52d to extend into a pair of integrally formed screw splines 67 formed on the inside surface of the flange 62.
The header trim element 60 includes an upwardly extending outer fascia portion 68 integrally joined to an outer edge of the flange portion 62 and the flange is formed with a narrow upwardly offset portion 62d for providing a lower drip edge 68a along the lower edge of the fascia 68. It should also be noted that the outer face of the fascia 68 is dimensioned to seat against the inside edge of the ribs 58a on the side trim elements 50.
The sill trim element 70 is substantially similar in transverse cross-section to the header trim element 60 but includes a downwardly and outwardly sloping flange portion 72 with a groove 73 formed by an upwardly extending wall segment 72a, an inwardly extending wall segment 72b, and an upstanding flange 72c completing the pocket which receives a lower edge of the outer face 42 of the lower rail 40 of the window frame. The pocket also includes an upper wall segment comprising a sharp edge tongue or stop 76 and an inside tongue 74 is adapted to pivotally interfit and interconnect the trim element 70 on the lower rail 40 in the groove 43 formed on the inside face of the wall member 42a.
A pair of integrally formed screw splines 77 are formed on the lower portion of the flange 72 for accommodating the threaded shanks of a pair of lower fasteners 61 projecting through the lower set of holes 52d which are provided in the flange 52 of the window side trim elements 50. The lower sill trim element 70 includes an outer fascia 78 parallel of the fascia 58 of the side trim elements 50 and the lower sill fascia is inset just behind the ribs 58a on the side fascia as illustrated.
In accordance with the present invention, the rectangular frame of stiles 38 and rails 40 of the replacement window 16 is dimensioned to fit freely inside the existing wall opening 12a, 12b, 12c, etc. with the trim members of the original window left in place after the old window sashes 14a and 14b have been removed.
In applying the trim elements to the frame of the window 16, the side trim elements 60 are first cut to length to fit within a window openings 12a, 12b, 12c, etc. and are then coped at the upper and lower ends as at 55 and 57. The flanges 52 are drilled with pairs of upper and lower holes 52d to accommodate the screw fasteners 61. The header trim element 60 and the sill trim element 70 are then cut to butt fit between the opposite side faces of the flanges 52 of the side trim element 50 and all of the trim elements are pivotally interconnected in position upon the respective window frame stile and rail members with the respective tongue and ribs 54, 64, 74, etc. engaged in the grooves 43. The respective trim elements are then rocked into final position as shown and the screw fasteners 61 are driven through the openings 52d into the pairs of screw splines 67 and 77 in the header trim element and sill trim element, respectively, and once these screws are driven home, the window frame of the replacement window 16 is provided with a complete and rigidly secured peripheral trim. A gunned-in-place seal of caulking material 80 is provided around the periphery of the window frame at the junction between the wall members 42a and the respective pockets 53, 63 and 73 of the trim elements 50, 60 and 70 attached thereto. When this seal is completed, the trimmed window 16 is ready for mounting and installation in an opening 12a, 12b, 12c, etc. of the existing wall structure 10.
Mounting and installation of a trimmed window 16 is accomplished by means of a plurality of small clip elements 82 which are preferably formed of short lengths cut from a length of extruded aluminum or other metal having the transverse cross-section as shown. The clip elements are attached to the inner face members 44 of the window frame of the replacement window 16 at appropriate intervals along all sides. Each clip element includes a relatively large base portion 82a and a right angle flange 82b having a rib 83 thereon adapted to interlockingly and pivotally engage the grooves 45 on the inner surface of the inside face members 44a of the window frame, as best shown in FIG. 8. After interlocking engagement is made, the clip elements 82 are pivoted in a counterclockwise direction as shown by the Arrow "B" in FIG. 8, until the base 82a is substantially perpendicular or normal to the inside face portion or walls 44a of the window frame. To finally secure the clip elements in place, threaded screw fasteners 85 are tightened and these fasteners extend through threaded openings formed in an intermediate flange 82c provided on the clip elements. Each clip element is formed with a rib 86 adjacent the outer edge of the intermediate flange 82c, and the rib is designed as a stop to bear against the inside face 44a of the window frame when the screws 85 are finally tightened to hold the clip element securely in place. It will thus be seen that the clip elements may be easily and rapidly attached to the inside face members 44 of the replacement window frame at appropriate intervals on the frame members by first seating and interlocking the ribs 83 of the clip elements in the grooves 45 and finally tightening the fasteners 85. When this is accomplished, the base portions 82a of the clip elements project inwardly at right angles to the side faces 44a of the window frame members in precision alignment.
After clip elements 82 have been attached to a trimmed window frame, the unit is bodily lifted into an awaiting opening 12a, 12b, 12c, etc. in the existing building wall 10. When in place, the base portion 82a of the clip elements are seated on shims or mounting block 88 of wood, which shims have been leveled and plumbed to vertical so that the frame of the window 16 will be properly aligned. Wood screws or other suitable fasteners 89 are then driven home through drilled holes in the clip element flanges 82a and suitable clearance holes in the mounting blocks or shims 88 until the threaded shanks are home in the existing window frame trim elements 20, 22 and 18 as illustrated.
This arrangement provides for a secure and rapid means for mounting a trimmed window frame in an existing opening. After the clips are secured in place to hold the window, the final outer caulking seal 59 is applied around the outer edges of the trim element fascia members 58, 68 and 78 to seal the replacement window into the existing building wall structure.
Once this step is completed, the building is closed in against the weather and interior trim stock may be applied to finish the installation procedure. Appropriate lengths of elongated interior trim elements 90 are cut and are snap fitted into the clip elements 82. The elongated trim elements preferably formed of extruded aluminum or other metal are cut to length to fit with the horizontals butt fitted against the flanged portions of the verticals. In general, the interior trim elements are of angular shaped, transverse cross-section and each includes a flange section 90a adapted to extend normal to the inside wall face 44a of the adjacent window frame member. On the free edge of the flange there is provided a wedge shaped rib 91 adapted to snappingly engage and interlock with a similar wedge shaped ridge 87 formed on the clip element flange 82c. The elongated interior trim elements 90 also include an interior fascia portion 90b perpendicular to the flange position 90a and the fascia portion is formed with a pair of spaced apart ribs on the interior surface thereof adapted to sandwich opposite sides of a thin edge portion of the face segment 82a of the clip elements as shown in FIGS. 2 and 3. The flange portion 90a of the interior trim elements is also provided with an integral L-shaped rib 94 having a free edge portion adapted to engage and slide against a rib 82d formed on the intermediate flange 82c of the clip elements. It will thus be seen that once an exteriorly trimmed replacement window 16 having previously had exterior trim elements 50, 60 and 70 attached thereto, is then mounted in a window opening 12a, 12b, 12c etc., and the clip elements 82 are fastened in place by the screws 89 and shims 88, the the elongated, interior trim elements 90 may then be cut to length and snapped in place onto the clip elements 82 by biasing the trim elements toward the clips until the wedge shaped ridges 87 and 91 snap into interlocking engagement.
Although the present invention has been described with reference to a single illustrated embodiment thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this invention. | A new and improved method and apparatus for replacing old windows in an existing building with new windows and surrounding trim comprises the use of elongated, especially designed trim elements which are cut to length and assembled onto the replacement window frame to trim the periphery thereof. The replacement window frame with the peripheral trim elements bodily attached thereto is then mounted in the opening in the building wall structure to replace an old deteriorated window previously removed therefrom. The novel method of assembly and installation guarantees a good fit between the trim elements and the window frame, and permits the critical seal between the trim elements and the window frame to be formed at a convenient location during the assembly of the trim elements onto the window rather than requiring a trim seal to be effected after the window is installed in the building. | 4 |
This is a continuation, of application Ser. No. 06/680,267, filed Dec. 10, 1984.
FIELD OF THE INVENTION
This invention relates to a process and apparatus for the production of ethylene, and more particularly to a process and apparatus for the production of ethylene by the pyrolysis of heavy hydrocarbon utilizing transfer line reactor techniques.
BACKGROUND OF THE INVENTION
Heater designs for effecting the pyrolysis of naptha to form ethylene have operated on low heat rates where the conversion of naptha to ethylene ranges from about 12 to 26 percent. Such heaters have included two parallel coils and a two zone radiant heating section to permit varying of the heating profile. Horizontal tube type heaters have metallurgical limitations of the tube supports when firing such heaters at intense service conditions as well as presenting serious expansion problems.
In U.S. Pat. No. 3,274,978 to Palchik et al and assigned to the same assignee as the present invention, there is disclosed a short residence heater of the vertical tube type having parallel radiant heating zones with a single convention zone disposed thereabove in fluid communication with the radiant heating zones. By locating high intensity radiant burners on either side of a single row of absorbing surfaces or coils permit the attainment of high heat absorption rates at concomitant low residence times. The coil is designed for residence times of about 0.3 second, generally from about 0.2 to 0.5 second at average heat rates of 20,000 to 30,000 B.t.u./hr./sq.ft. At such low residence times, high outlet temperatures in the order of about 1500° to 1550° F. are required for the decomposition of the feed to form the desired olefins before coke condensation reactions become significant.
The lower limit of residence times in such tubular type heaters is limited by the maximum heat rate allowable and the practical limit of the smallness of the tube diameter. Thus, high pyrolysis temperatures are required for heavy hydrocarbon feeds with vaporization of the feed in the tube resulting in coke build-up, it being understood that high ethylene yields are achieved by high pyrolysis temperatures and short residence times.
Higher pyrolysis temperatures have been achieved utilizing transfer line exchangers wherein pyrolyzing temperatures are achieved by admixing heated solids with the hydrocarbon feed to be pyrolyzed, such as disclosed in U.S. Pat. Nos. 4,057,490 and 4,172,857 to Wynne and Pavilon, respectively. In U.S. Pat. No. 4,057,490 to Wynne, crushed oil shale is heated to a temperature of from 1300° to 2500° F. prior to introduction into the riser, whereas in U.S. Pat. No. 4,172,857 to Pavilon, agglomerated ash particles formed by burning particles of coal or other solid carbonaceous material are introduced into the riser reactor.
In ethylene production, it is most important to stop the reaction within a predetermined time, or to at least substantially rapidly reduce the reaction rate, in order to avoid the formation of by-products and residues resulting from secondary reactions and to thereby maximize the yield of the desired product. Thus, the hydrocarbon feed is introduced into a reaction zone at a very high throughput rate and rapidly brought to reaction temperature, and maintained at this temperature for a time period which may be on the order of a fraction of a second. Under these conditions ethylene is the primary resulting product.
If the reaction products are not cooled immediately, secondary reactions, such as polymerization, takes place with a resulting production of tars and coke and a reduction in ethylene yields. Aside from such evident disadvantages, there is the fact that if such secondary reactions are allowed to take place, the tars and coke which are produced tend to clog and block the pipelines, valves and other components of the apparatus with concomitant complicated maintenance problems and frequent plant shutdown.
OBJECTS OF THE PRESENT INVENTION
An object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydrocarbon.
Another object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydrocarbon with improved ethylene yields.
A further object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydrocarbon of improved ethylene yields utilizing a transfer line reactor and the quenching of the pyrolysis effluent by cooled solids preferably cake particles.
Yet a further object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydrocarbon of improved ethylene yields utilizing transfer line reactor techniques substantially eliminating the attendant problems of coke, tar and other heavy hydrocarbons.
Still another object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydrocarbon of improved ethylene yields utilizing transfer line reactor techniques with solids produced by the combustion of comminuted coke particles.
A still further object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydro carbon of improved ethylene yields utilizing transfer line reactor techniques with solids produced by the combustion of comminuted coal and limestone particles to reduce sulfur oxide pollution.
Yet another object of the present invention is to provide an improved process and apparatus for producing a pyrolysis effluent including ethylene from a heavy hydrocarbon of improved ethylene yields utilizing transfer line reactor techniques of affording substantial economies.
Still another object of the present invention is to provide a novel process and apparatus for producing a pyrolysis effluent including ethylene whereby the pyrolysis effluent is quenched with cooled coke particles to enhance adsorption of tars, coke and other heavy materials.
SUMMARY OF THE INVENTION
These and other objects of the present invention are achieved in a transfer line reactor wherein pyrolysis reaction temperatures are achieved by contact of a heavy hydrocarbon feed with heated solid particles immediately followed by quenching of the pyrolysis gaseous effluent with cooled solid particles in the transfer line reactor. In one aspect of the present invention, the heated solid particles are formed by burning comminuted coal particles in the presence of limestone to fix sulphur oxides as calcium base compounds.
BRIEF DESCRIPTION OF THE DRAWING
A better understanding of the present invention as well as other objects and advantages thereof will become apparent upon consideration of the detailed disclosure thereof, especially when taken with the accompanying drawing of a schematic flow diagram of the process and apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
It is to be understood that certain equipment, such as valves and indicators, and the like have been omitted from the drawing to facilitate the description hereof, and the placment of such equipment at appropriate places is deemed to be within the scope of one skilled in the art.
Referring now to the drawing, there is illustrated a transfer line reactor assembly, generally indicated as 10, and comprised of a transfer line reactor 12, a fluidized coke heater 14, a separator 16 and a cooler 18. The fluidized bed combustion boiler 14 is provided with a recycle solids inlet conduit 20, a fresh solids inlet conduit 22 in solids communication with solids supply conduit 24 for the introduction of comminuted coke particles or like carbonaceous particles for start up procedure and a solids supply conduit 26 for the introduction of comminuted limestone, as more fully hereinafter described. The fluidized coke heater 14 is provided with a gas inlet conduit 28 for the introduction of an oxygen-containing gas, such as air into the boiler 14 via the fluidize bed distribution assembly, generally indicated as 30, and with a gas outlet conduit 32 including cyclone separator 34. Hot solid particles are withdrawn by solids conduit 36 for introduction into the generally vertically-disposed transfer line reactor 12.
A portion of the transfer line reactor 12 below the solids conduit 36 is provided with a feed inlet conduit 38. Above the juncture of the solids conduit 34 with the transfer line reactor 12, there are provided on the transfer line reactor 12, solids conduits 40 and 42 in solids communications by line 44 with the cooler 18, as more fully hereinafter described. The upper portion of the transfer line reactor 12 is in gas-solid communication with the separator 16 including stripper portion 46. The separator 16 is provided with an outlet gas conduit 48 and a solids outlet conduit 50 in gas and solids communication, respectively, with the cooler 18. The stripper portion 46 of the separator 16 is provided with a stripping gas inlet conduit 52 with the lower portion of the stripper portion 46 being in solids communication with the fluidized coke heater 14 via the conduit 20.
The cooler 18 is provided with a fluidized bed grid 54, a solids outlet conduit 56 and a gas outlet conduit 58 including cyclone separator 60, and is in gas and solids communication by conduits 48 and 50, respectively, with the separator 16, as hereinabove described. The cooler 18 is provided with a heat transfer coil 62 in fluid communication with a steam drum 64 by a liquid conduit 66 and a steam conduit 68. The stream drum 64 is provided with a steam outlet line 70.
In operation, solid particles of coke or like carbonaceous material heated to a temperature of from 800° to 1700° F., preferably from 1200° to 1600° F., are introduced by line 36 into the transfer line reactor 12 and contact an atomized heavy hydrocarbon feed at a pressure of from 2 to 10 atmosphere, absolute introduced by line 38 into the transfer line reactor 12 at weight ratios of heated solid particles to heavy hydrocarbon feed of from 25:1 to 1:1, preferably 15:1. The large surface area of the heated solid particles substantially instantaneously heat the heavy hydrocarbon feed to pyrolysis temperatures of from 300° to 1500° F., preferably from 500° to 1400° F., at pressures of 2 to 10 atmospheres, absolute.
Coke is a particularly preferred solid material since direct quench of the effluent from the pyrolysis of heavy hydrocarbons with cooled coke particles enhances the adsorption of tar, coke or other heavy material. The use of coke particles has by far the advantage of being of like material as the absorbed coke and is of a high heat capacity, readily burned in the coke heater.
As hereinabove discussed, elevated pyrolysis temperatures favor ethylene production whereas extended residence times favor secondary reactions including char formation. To substantially arrest or halt the pyrolysis reaction after a desired residence time of from 0.02 to 1 seconds, cooled solid particles at a temperature of from 500° to 1000° F., preferably from 700° to 900° F., are introduced by line 40 and/or line 42 into the transfer line reactor 12. The ratio of cooled solid particles in line 40 and/or 42 to the hot solid particles in line 36 is from 10 to 1 to 2 to 1. Heavier components of the pyrolysis effluent are condensed on the cooled solid particles transported through line 44 and are coked onto the solid particles in the transfer line reactor 12. Generally, lines 40 and/or 42 are positioned at a distance of from 2 to 20 feet, preferably 3 to 15 feet from the juncture between line 36 with transfer line reactor 12.
As is readily apparent to one skilled in the art, the residence time of pyrolysis is readily controlled by the distance between the contact point of the hydrocarbon feed with the hot solids particles and the contact point of the pyrolysis effluent including solids particles with the cooled solid particles. The velocity in the transfer line reactor 12 is from 15 to 60 feer per second with a concentration of solids therein of from 1 to 6 pounds per cubic feet.
The pyrolysis products and solid particles are lifted in the transfer line reactor 12 and are introduced into the separator 16 for separation into a gaseous pyrolysis stream withdrawn by line 48 and passed to cooler 18 with a portion of the separated solids from separator 16 being withdrawn and passed by line 50 to the cooler 18. The remaining portion of the solids particles in separator 16 are contacted with steam in line 52 in the stripper 46 to recover hydrocarbon absorbed on the surface of the solids and those entrapped between the solids prior to withdrawal from the separator 16 by line 20 for passage to fluidized coke heater 14.
The solids particles in line 20 together with solids feed, if any, in line 22 are contacted in the fluidized coke heater 14 with air or an oxygeneous gas in line 28 under conditions to provide the hot solid particles in line 36. If the carbonaceous solids in line 24 contain sulfur compounds in an amount to present environmental problems, the combustion in the fluidized coke heater 14 is effected in the presence of calcined limestone introduced by line 26. Combustion is complete at about 1600° F. with the result that sulfur oxides are reduced by reaction with the calcined limestone.
Use of coal or like carbonaceous material from the boiler 14 to furnish the heat necessary for pyrolysis eliminates extraneous heating liquids or fluids, such as oil and/or gas, it being understood that some of the feed is converted to coke or char deposited on the solid particles for subsequent combustion in the fluidized coke heater 14. Additionally, the use of the fluidized coke heater 14 permits the generation of steam by passage of the combustion gases in line 32 in indirect heat transfer relationship (not shown) for on-site plant use or for preheating air in line 28 by indirect heat exchange with flue gas in line 32.
The pyrolysis effluent including stripped components and stripping steam are withdrawn by line 48 from the separator 16 and introduced into the cooler 18 and contact fluidized solids therein including solid particles withdrawn by line 50 from the separator 16 with the pyrolysis effluent in line 48 provides the fluidizing gas requirements therefor. Generally, there are still additional heavier components of pyrolysis in line 48 which are deposited on the solids in cooler 18 thereby to substantially remove such components therefrom. Thus, lighter components of pyrolysis partially cooled and substantially free from heavy components with fouling tendencies on cooling surfaces are withdrawn by line 58 and passed to a cooling fractionation and purification system (not shown).
Operation of the process and apparatus of the present invention is described in the following specific example which is intended to be merely illustrative and the present invention is intended not to be limited thereto.
EXAMPLE
The system is filled with fluid coke for start-up. The coke in the coke heater 14 is heated and maintained at about 1600° F. by burning a portion of the coke. Heavy oil is atomized with about an equal weight of steam and introduced by line 38 into the transfer liner reactor 12. Hot coke in line 36 in an amount of about 10 times of the oil feed is introduced into the transfer line reactor 14 to contact the steam and oil mixture. The oil begins to pyrolyze in contact with the hot coke particles. The pyrolysis reaction is endothermic. Thus, the temperature of the mixture drops to about 1400° F. as it proceeds along the transfer line reactor 14. The final pyrolysis temperature is determined by the degree of conversion desired and the residence time allowed for the heavy oil. The pyrolysis reaction is arrested by introducing a cooled coke stream at 800° F. from coke cooler 18 through line 40 and/or 42 to cool the pyrolyzed mixture to about 1200° F.
For 100,000 lb/hr ethylene production, the heavy oil feed is about 400,000 lb/hr preheated to about 350° F. and atomized with 400,000 lb/hr of 100 psig steam. About 6,800,000 lb/hr of hot coke at 1600° F. is introduced into the transfer line reactor 14 and maintained at a pressure of about 30 psig. The diameter of the reactor is sized to maintain a velocity of 30 ft/sec. At about 10 ft. from the inlet, about 3,800,000 lb/hr of cooled coke at about 800° F. is introduced to cool the mixture to 1200° F. The residence time of the oil and steam mixture in pyrolysis zone is about 0.3 seconds. The residence time can be varied by introducing the cooled coke at different points into the transfer line reactor 14. The temperature in the pyrolysis zone is varied by the temperature and quantities of the hot coke used. The degree of conversion of the heavy oil is achieved by the combination of the residence time and the temperature in the pyrolysis zone.
The pyrolysis products are separated from the coke in the separator 16 and sent to the cooler 18 through conduit 48 and used as fluidizing gas for the cooler 18. A part of the coke, about 3,800,000 lb/hr, separated from the vapor in separator 16 is recycled to the cooler 18 to be cooled to 800° F. in a fluidized bed cooled by thermosyphon water/steam coils 62. The effluent vapor from separator 16 containing unstable high boiling hydrocarbons is contacted in cooler 18 with a cooled fluidized bed of coke. These high boiling hydrocarbons are absorbed by the coke which is recycled to the reactor 12 and ultimately sent to the coke heater 14 where these hydrocarbons are burned. The vapor effluent 58 from the coke cooler is sent to a steam generating cooler (not shown) to be cooled down to about 600° F. generating about 90,000 lb/hr of 750 psig steam. As most of the high boiling unstable hydrocarbons are removed from the vapor, the fouling of the steam generating cooler is much less than that occurring in a transfer line exchanger cooling the effluent stream from a conventional pyrolysis heater.
The cooled stream from such steam generating cooler is sent to a fractionator (not shown) in which the heavy pyrolysis residual oil is separated from the light pyrolysis products. The overhead from the fractionator is sent to a recovery section to purify and recover all the pyrolysis products. The amount of the heavy residual oil recovered can be adjusted to balance the heating oil required for the coke heater 14. The other portion of the coke, about 6,800,000 lb/hr separated out the separator 16, is sent through a stripper 46 in which the reaction products are stripped-out by steam in conduit 52 and returned to the separator 16. The stripped coke is sent to the coke heater 14 through conduit 20.
The heat required to heat 6,800,000 lb/hr of coke from 1200° F. to 1600° F. is about 1,400 million B.t.u/hr at an efficiency of about 80%. The heat from fuel is about 1,700×10 6 B.t.u/hr. The amount of coke produced by the pyrolysis reaction is about 10,000 lb/hr and is deposited on the circulating coke. The burning of such coke generates about 140 million B.t.u/hr. The balance of the heat requirement is supplied by burning about 84,000 lb/hr of the heavy residual oil recovered from the fractionator.
About 2,500,000 lb/hr of air is required for the combustion in the coke heater 14. The preheated air is introduced through conduit 28 to the sparger 30 located at the bottom of the fluidized bed in the coke heater 14. The flue gas is separated from the coke in the cyclone 34 and is sent to a heat exchanger by line 32 to preheat the air in the conduit 30 to about 1000° F. The remaining heat of about 400 ×10 6 B.t.u/hr in the flue gas in line 32 is recovered in a heat recovery unit generating medium pressure steam (not shown).
While the present invention has been described with reference to a preferred embodiment thereof and in particular the use of coke or like carbonaceous solid particles as the source material for forming hot solid particles at pyrolysis temperatures, it is understood that other solids and/or other sources of energy may be utilized to substantially instantaneously achieve pyrolysis temperatures and that like cooled solids may be utilized as a quenching medium.
In accordance with the present invention, the direct quench of the pyrolysis effluent resulting from the pyrolysis of a heavy hydrocarbon feed enhances the absorption or deposition on the cooled coke particles of tar, coke or other heavy materials of pyrolysis. The thus formed coke has the advantages of being the same material formed during the pyrolysis and of a high heat capacity capable of being burnt as fuel. The resulting gaseous effluent is substantially free of fouling components thus permitting the use of conventional heat transfer equipment downstream of the separator.
While the invention has been described in connection with an exemplary embodiment thereof, it will be understood that many modifications will be apparent to those of ordinary skill in the art; and that this application is intended to cover any adaptations or variations thereof. Therefore, it is manifestly intended that this invention be only limited by the claims and the equivalents thereof. | There is disclosed an improved process and apparatus for the pyrolysis of a heavy hydrocarbon feed utilizing a transfer line reactor wherein pyrolysis reaction temperatures are achieved by contact of the heavy hydrocarbon feed with heated solid particles immediately followed by quenching of the pyrolysis gaseous effluent with cooled solid-particles in the transfer line reactor to maximize ethylene production and minimize the effect of secondary reactions. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority on U.S. Provisional Application No. 61/136,926, filed on Oct. 15, 2008, which is herein incorporated by reference.
FIELD OF THE INVENTION
The present invention generally relates to an apparatus and a method for consolidating a bundle of cables. More precisely, the present invention is concerned with an apparatus and a method for consolidating a harness with a surrounding tape applied over the bundle of cables.
BACKGROUND OF THE INVENTION
Complex products or industrial equipments are using wires to channel power and control signals between various components therein. In modern vehicles, for instance, it is possible to find a significant number of wires or electric cables disposed between various electronic and electrical components. These cables need to be conveniently packaged in a harness to be safely and easily installed.
The harness has a generally arbitrary shape adapted to its unique use. The harness comprises nodes, from which branches of electrical wires project toward connection ends in order to interconnect each components such as lights, electronic boards, actuators and sensors. A harness can be more or less complex depending on the number of systems it has to interconnect.
The wires forming the harness are tied together with a protective layer disposed thereon. The protective layer is commonly a layer of tape that is installed over the group of wires to ensure that all wires routed similarly are joined together. Additionally, the tape can be discontinuously applied on over the wires to leave some desired area uncovered thus leaving direct access to the wires. If the harness provides a number of branches leading to various connection ends the branches are also protected with a layer of tape.
The tape can be manually installed over the bundle of wires. Alternatively, a machine can be used to apply significant amount of tape over the wires.
A prior art taping machine 10 is illustrated on FIG. 1 . The taping machine 10 is a portable taping machine in the sense that it must be manually held by the user. The user grabs the handle 12 , pass the group of wires to be taped together within the safety cover 14 through the aperture 16 . For so doing, the aperture 16 needs to be aligned with the opened door 18 to have access to the central opening 20 .
Once the group of wires is located in the central opening 20 the user press the actuation button 26 to power the motor 22 to rotate the central portion 24 of the taping machine 10 . The central portion of the taping machine 10 accommodates a roll of tape (not visible on FIG. 1 ) to revolve the roll of tape about the group of wires to secure the group of wires together and form a harness of wires.
The illustrated prior art taping device 10 can be suspended by the hook 26 to reduce the weight supported by the user. Once the taping machine 10 is properly held and wires are disposed inside the central opening 20 the user actuates the rotation of the central portion 24 and slowly moves along the cables to wrap the desired portion of cables with tape.
Due to the complexity of certain harnesses having different lengths and number of branches a solution for automating the taping procedure in a sufficiently simple and viable manner has yet to be found. A problem with prior art solutions is the possibility of providing inconsistent quality and, therefore, in certain cases, defects in the harness. Another issue present with the prior art is that they need to be manually manipulated thus increasing the fatigue of the person operating the taping machine. One other downfall of prior art solutions is that the operator moves the machine as opposed to move the harness, which is usually lighter.
It would therefore be desirable to render the harness taping procedure less labor intensive, in a cost effective manner, whilst ensuring flexibility, simplicity and reliability. An improved apparatus and an improved method for taping wires to form a harness are therefore desirable over the existing art.
SUMMARY OF THE INVENTION
In accordance to the present invention, there is provided an apparatus and a method for applying a layer of tape over a group of cables, electric wires, communication wires and/or fiber optic cables to consolidate the group of cables/wires in a harness.
An aspect of the present invention provides a taping machine having a doorless central rotating portion.
Another aspect of the present invention provides a portable taping machine that can be easily disposed on a surface.
An aspect of the present invention provides a battery powered taping machine.
An additional aspect of the present invention provides a rechargeable mechanism adapted to recharge the battery and to selectively draw power from the grid to power the taping machine.
An aspect of the present invention provides a battery powered portable taping machine.
One other aspect of the present invention provides a taping machine having a vented enclosed structure.
Another aspect of the present invention provides a taping machine comprising a counter weight counter balancing the weight of the roll of tape when the roll of tape revolves about the moveable portion axis.
One aspect of the present invention provides a moveable portion held in place by a grooved portion defined therein in conjunction with a series of bearings engaging the grooved portion.
An aspect of the present invention provides a moveable portion that is rotated by at least one driven wheel engaging a grooved portion defined therein.
One aspect of the present invention provides a friction-enhancing surface on the driven wheel to increase the friction between the driven wheel and the grooved portion.
Another aspect of the present invention provides a safety lever laterally disposed from the moveable portion and adapted to influence the movement of the moveable portion when actuated.
One aspect of the present invention provides an array of moveable portion supports from which at least one is a bearing and at least one is a driven wheel adapted to apply motion to the moveable portion.
Another aspect of the present invention provide a tape roll support adapted to receive a tape roll, the tape roll support defining an axis that is not parallel with the axis defined by the moveable portion wherein the angle formed therebetween tend to force the taping motion toward the untaped portion of the wire to be taped. The tape roll support also provides an adjustable tension on the tape roll to provide a desired tension of the tape on the harness.
One additional object of the present invention provides a remote actuator to remotely actuate the taping machine; the remote actuator being preferably a pedal actuator to free the hand of the operator.
An additional objet of the present invention provides a variable speed taping machine wherein the revolving speed of the tape roll is variable.
An aspect of the present invention provides a belt drive mechanism adapted to couple the electric motor to the drive wheels.
One additional aspect of the present invention provides a clutch adapted to couple the electric motor to the drive wheels over a predetermine range of torque.
An other aspect of the present invention provides an apparatus for applying tape on a plurality of wire to form a harness thereof, the apparatus comprising a casing defining a fixed portion adapted to rotatably receive a moveable portion rotatable about a moveable portion axis, the moveable portion being adapted to secure a roll of tape thereon such that the roll of tape revolves with the moveable portion in a fashion allowing unwinding of the tape on the plurality of wires, the fixed portion and the moveable portion defining cooperating indentations encompassing the moveable portion axis, the indentation in the moveable portion being adapted to be selectively aligned with the indentation of the fixed portion to receive and allow positioning of the plurality of wires about the moveable portion axis such that the tape on the rotating moveable portion being unwounded on the plurality of wires to secure the plurality of wires in a harness.
Another aspect of the present invention provides a method for manufacturing a wiring harness, the method comprising aligning an indentation of a moveable portion with an indentation of a fixed portion; inserting a plurality of wires in the aligned indentations; and actuating a rotation of the moveable portion such that a roll of tape attached thereto revolves about the plurality of wires to tapedly secure the plurality of wires into a wiring harness.
An additional aspect of the present invention provides a taping apparatus adapted to apply tape on a plurality of wires to manufacture a wiring harness, the apparatus comprising a rotatable means adapted to rotate a roll of tape about the plurality of wires, the rotatable means further defining a doorless recess therein adapted to receive the plurality of wires therein, the recess being selectively accessible by rotating the rotating means.
The foregoing and other objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of an illustrative embodiment thereof, given by way of example only, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the appended drawings:
FIG. 1 is perspective view of a prior art taping machine;
FIG. 2 is a perspective view of an illustrative example of a taping machine in accordance with the present invention;
FIG. 3 is a perspective view of the taping machine of FIG. 2 with a group of wires;
FIGS. 4-6 are left elevation side views of the taping machine of FIG. 2 illustrated at different stages of the taping process;
FIG. 7 is a perspective view of the taping machine of FIG. 2 ;
FIG. 8 is an exploded view of a portion of the taping machine of FIG. 7 ;
FIG. 9 is a perspective view of the taping machine of FIG. 2 with a removed portion of the casing;
FIG. 10 is a front elevational view of the taping machine of FIG. 2 with a sectional view of the front face of the taping machine;
FIG. 11 is a top elevational view of the taping machine of FIG. 2 with a section of the casing removed to see a portion of the driving mechanism;
FIG. 12 is a right side elevational section view of the taping machine of FIG. 2 ;
FIG. 13 is a perspective view of the taping machine of FIG. 2 partially viewed from behind;
FIG. 14 is a perspective view of the taping machine of FIG. 2 partially viewed from the bottom; and
FIG. 15 is a left side elevational view of the taping machine of FIG. 2 illustrating the movement of the safety arm.
DETAILED DESCRIPTION OF THE INVENTION
An apparatus for taping at lest one wire or a plurality of wires into a harness, and a method thereof, in accordance with a non-restrictive illustrative embodiment of the present invention, will now be described.
An illustrative example of the taping apparatus of the present invention is shown on FIG. 2 . The taping apparatus 50 comprises a casing 52 defining an upper top portion 54 , a lower top portion 56 , an upper front portion 58 , a lower front portion 60 , a right side portion 62 , a left side portion 64 and a bottom portion 66 . All these casing portions are illustratively made of sheet aluminum assembled together to form the casing 52 but could otherwise be made of another material without departing from the scope of the present invention. A fiber filled plastic casing is another option that would provide a reduced weight enclosure to the taping apparatus 50 .
The taping apparatus 50 is transportable using the handle 72 secured to the casing 52 . Other means for holding the taping apparatus 50 can be added to the actual embodiment in accordance with the possible dedicated uses of the taping apparatus 50 . The taping apparatus 50 is also designed to rest on a table or a flat surface. A power pack 68 , not visible on FIG. 2 , is included in the casing 52 to remotely use the taping apparatus 50 . The power pack 68 is a battery 74 in the present embodiment. A 12-Volt battery 74 is electrically connected to the DC motor (that will be discussed later in the description) that powers the taping apparatus 50 . The battery 74 powers the taping apparatus 50 without requiring the taping apparatus 50 to be connected to the electric grid. However, the taping apparatus 50 can be used when the power pack 68 is connected to the electric grid. The taping apparatus 50 can be plugged in to the grid to recharge the power pack 68 with a removable wire removably connected into a connector located on the casing 52 . The taping apparatus 50 can alternatively be powered from the grid if the battery is weak while the battery is recharging. A series of venting holes 70 are disposed on the right side portion 62 to allow air to access the interior of the casing 52 to vent and cool the power pack 68 .
Still referring to FIG. 2 , the casing 52 accommodates a cable receiving portion 80 . The cable receiving portion 80 includes a lower top portion extension 82 . The lower top portion extension 82 extends the lower top portion 56 toward the fixed portion 84 to reduce the gap that can be formed therebetween and help prevent wires to jam therein.
The cable receiving portion 80 further includes a fixed portion 84 , a moveable portion 86 and an array of rollers 88 individually secured to the fixed portion 84 with a nut 90 . The rollers 88 are miniature can follower as they can be found into NTN Corporation's Cam Followers & Roller Followers Catalogue No. 3604-VI/JE. The NTN catalog can be found at www.ntn.co.jp/English/products/pdf/camandroller/pdf/camandror_all.pdf
The rotation of the moveable portion 86 is performed about a moveable portion axis 94 . The moveable portion 86 defines a circumferential guide 92 adapted to receive a portion of the rollers 88 therein to rotatably axially secure the moveable portion 86 to the fixed portion 84 . As best seen on FIG. 3 , whenever a wire or a group of wires is taped with the machine, the wire(s) should ideally be located as close as possible to the moveable portion axis 94 to help ensure a more consistent tape wrapping over the wire(s) 112 . In the present illustrative embodiment the taping apparatus 50 is provided with a cable receiving portion 80 defining an opening with a diameter of about fifty (50) millimeters. A smaller or larger receiving portion 80 is encompassed by the present invention if required by the size of the harness.
Still referring to FIG. 2 the fixed portion 84 defines a fixed portion indentation 96 while the moveable portion 86 defines an axially cooperating moveable portion indentation 98 . Both indentations 96 , 98 are encompassing the moveable portion axis 94 and are adapted to be aligned to receive the wire(s) to be taped therein. The rotation of the moveable portion 86 alternatively close the fixed portion indentation 96 and might need to be aligned in order to insert the wire(s) in the indentations 96 , 98 along the moveable portion axis 94 .
The moveable portion 86 further includes a tape roll support 100 adapted to receive a roll of tape 102 and a counterweight 104 . The roll of tape 102 is disposed in such a way that the tape 114 (not visible on FIG. 2 ) can be unwound on the wire(s) put in the indentations 96 , 98 along the moveable portion axis 94 . The securing of the roll of tape 102 is adjustable to provide the desired tension on the tape when the tape is installed on the harness. The counterweight 104 , disposed on the opposite side of the tape roll support 100 , helps reduce the vibration provided by the weight of the roll of tape 102 when the moveable portion 86 revolves at a significant speed. A safety lever 106 is also visible and will be described in details later in the present description.
Turning now to FIG. 3 illustrating the same taping apparatus 50 as FIG. 2 with the addition of a cable 110 installed thereon. The cable 110 is formed from a plurality of smaller wires 112 that are consolidated into a single bigger cable 110 , or harness, once covered by the tape 114 . The rotational movement of the moveable portion 86 is illustrated by arrow 116 on FIG. 3 .
Referring now to FIGS. 4-6 where is illustrated the rotational movement, still illustrated by arrow 116 , of the moveable portion 86 about the moveable portion axis 94 . It is possible to appreciate the unwinding of the tape 114 from the roll of tape 102 over the plurality of small wires 112 . Each time the roll of tape 102 performs a complete revolution about the wires 112 the tape 114 covers a portion of the length of the wires 112 . The user longitudinally moves the wires 112 at a speed corresponding to the speed at which the tape 114 covers the wires 112 . Once the desired portion of wires 112 is covered with tape 102 the user stop the taping apparatus 50 , cut the tape 102 and remove the wire from the aligned indentations 96 , 98 . A sensor 108 can be mounted to the cable receiving portion 80 to sense the position of a corresponding mark 118 disposed on the moveable portion 86 to stop the motion of the moveable portion 86 when the indentations 96 , 98 are aligned. The sensor 108 is also used for counting the number of revolutions performed by the moveable portion 86 for maintenance purposes.
Additionally on FIGS. 4-6 is depicted a small ventilator 120 used in cooperation with the series of venting holes 70 disposed on the opposite side of the casing 52 . The ventilator 120 helps channel air through the casing 52 to prevent overheating of the power pack 68 and the motor 122 inside the casing 52 , that will be described in further details in Figures to come, that actuates the moveable portion 86 . A switch 124 used to cut the electric current from the power pack 68 and a rotational speed adjustment 128 (not visible on FIG. 4 ) are also seen on the control panel 126 .
Turning now to FIG. 7 where is illustrated the taping apparatus 50 in a different angle so that the cable receiving portion 80 is not hidden by the casing 52 . The cable receiving portion 80 is isolated and illustrated in an exploded view at FIG. 8 .
The driving mechanism of the moveable portion 86 is better seen on the exploded view of FIG. 8 showing the motor 140 , the drive gear 142 , the tensioner 144 , the endless belt 146 and the driven gears 148 . All these parts are contained inside the casing 52 and are cooperating to transfer rotational power from the motor 140 to the moveable portion 86 via two drive wheels 150 . The pair of drive wheels 150 is replacing two rollers 88 and is turning with the driven gears 148 in which they are engaged thereto. The drive wheels 150 preferably have the same size as the rollers 88 to fit in the circumferential guide 92 of the moveable portion 86 . The exterior surface of the drive wheels 150 contacting the moveable portion 86 are preferably equipped with a friction enhancing surface ensuring good gripping to the moveable portion 86 .
The motor 140 , the drive gear 142 , tensioner 144 , the endless belt 146 and the driven gears 148 are mounted to a support 152 to ensure proper interactions among all the parts. The support 152 is spaced apart from the left side portion 64 with a pair of spacers 154 to allow sufficient space for the drive gear 142 , tensioner 144 , the endless belt 146 and the driven gears 148 assembly. The drive gear 142 is mounted to a shaft 156 adapted to fit into a bearing member 158 disposed into the lower portion of the fixed portion 84 thus preventing the drive gear 142 to be in cantilever. Additionally, the driven gears 148 are mounted on bearings 160 secured to the support 152 . The driven gears 148 include a support bearing 162 adapted to engage corresponding openings 164 in the fixed portion 84 . Therefore, when the motor 140 is powered, it turns the driven gears 148 that turn the two drive wheels 150 contacting the moveable portion 86 and rotating the moveable portion 86 .
FIGS. 9-12 illustrate how the motor 140 and the other transmission parts are disposed into the casing 52 . The motor 140 is located under the lower top portion 56 (the lower top portion is removed on FIG. 9 for a better understanding of the layout). It can be appreciated from FIG. 10 that the motor 140 is connected to the drive gear 142 using a coupling 170 helping to reduce vibration transfer between the engine and the rest of the cable receiving portion 80 and to ease removal of the motor 140 for maintenance.
The taping apparatus 50 is optionally provided with a clutch (not illustrated on the Figures) intervening between the motor 140 and the drive wheels 150 . The optional clutch is preferably preset to a maximum torque as a safety measure in case the movable portion 86 is stopped while the taping apparatus 50 is powered. The clutch can be a well known dry friction clutch installed directly at the output of the motor 140 .
Turning now to FIG. 13-15 where the focus is put on the safety lever 106 . The safety lever 106 is adapted to prevent injuries of the user when the user uses his hand to position the wires 112 before the tape 114 is applied. The safety lever 106 pivots about pivot 168 in accordance with the movement indicated with arrow 166 . A safety sensor (not visible) is actuated by the movement of the safety lever 106 to stop the movement of the moveable portion 80 . A lateral movement of the safety lever 106 toward the left side portion 64 could also trigger the safety sensor to stop the taping apparatus 50 .
Although the present invention has been described hereinabove by way of non-restrictive, illustrative embodiments thereof, these embodiments can be modified at will, within the scope of the appended claims, without departing from the spirit and nature of the subject invention. | There is provided an apparatus for applying tape on a plurality of wire to form a harness thereof, the apparatus comprising a casing defining a fixed portion adapted to rotatably receive a moveable portion rotatable about a moveable portion axis, the moveable portion being adapted to secure a roll of tape thereon such that the roll of tape revolves with the moveable portion in a fashion allowing unwinding of the tape on the plurality of wires, the fixed portion and the moveable portion defining cooperating indentations encompassing the moveable portion axis, the indentation in the moveable portion being adapted to be selectively aligned with the indentation of the fixed portion to receive and allow positioning of the plurality of wires about the moveable portion axis such that the tape on the rotating moveable portion being unwounded on the plurality of wires to secure the plurality of wires in a harness. | 1 |
This is a divisional of application Ser. No. 09/091,146, filed Jun. 4, 1998, now abandoned, which is the U.S. National Phase of International Appln. No. PCT/DK96/00513, filed Dec. 5, 1996. The most recent of these prior applications is hereby incorporated herein by reference, in its entirety.
This invention relates to a process of producing DNA consisting of multiple tandem repetitions of an oligonucleotide unit and a cascade nucleic acid amplification reaction producing a great number of partial and complete DNA or RNA copies thereof. The invention also relates to the application of these reactions in a method of detecting a target molecule or group at a specific site and a process for the amplification of a particular DNA sequence.
BACKGROUND OF THE INVENTION
The well-known polymerase chain reaction (PCR) is a process for amplifying any specific nucleic acid sequence contained in a nucleic acid or mixture of nucleic acids. In general, the process involves a chain reaction for producing, in exponential quantities relative to the number of reaction steps involved, any specific nucleic acid sequence given (a) that the ends of the sequence are known in sufficient detail that two oligonucleotide primers can be synthesized which will hybridize to them, and (b) that a small amount of the sequence is available to initiate the chain reaction. The process comprises treating separate complementary strands of the nucleic acid with a molar excess of two oligonucleotide primers, and extending the primers in the presence of a nucleic acid polymerase and the four necessary nucleoside triphosphates to form complementary primer extension products which act as templates for synthesizing the specific nucleic acid sequence. When the complementary strands of the nucleic acid are separated, e.g. by heating, the strands are ready to be used as templates for the synthesis of complementary strands by primer extension thus doubling the number of copies of the specific nucleic acid sequence. The steps of strand separation and extension product synthesis can be repeated as often as needed to produce the desired quantity of the specific nucleic acid sequence. This basic process is described and claimed in U.S. Pat. No. 4,683,202, and variants thereof are described and claimed in the related U.S. Pat. Nos. 4,683,195 and 4,800,159.
Becton Dickinson has described a variant of the PCR technique where the thermocycling is replaced by an enzymatic destruction of the primers, thus freeing the target sequence originally binding the primer to make it able to bind a new primer (EP 0 497 272 A1, EP 0 500 224 A2, EP 0 543 612 A2). After binding of the second primer to the target sequence, the product generated by chain elongation from the first primer is removed by strand displacement as the second primer is elongated. Like PCR, this reaction employs primers annealing to both ends of a biological DNA molecule with the purpose of amplifying the intervening biological sequence. This is unlike the present DNA cascade which relies on primers annealing along the length of a constructed tandemly repeated sequence (referred to as “polymer”).
Strand displacement is also involved in other DNA techniques such as the commonly used random priming labeling of hybridization probes. However, in this approach all DNA present can serve as template for the reaction. This is unlike the present DNA cascade, which is restricted to a specific pre-selected template.
PRINS reactions can also be enhanced by strand displacement DNA synthesis after destruction of already elongated primer, as described by this inventor and patented by Boehringer Mannheim. Like the Becton Dickinson reaction, this produces multiple copies of a biological target sequence, but does not have the characteristics of the present DNA cascade reaction.
J. W. IJdo et al., Nucleic Acids Research, Vol. 19, No. 17, p. 4780 (1991), report the rapid generation of human telomere repeat sequence (TTAGGG) n , with fragment sizes up to 25 kb, using a technique related to the polymerase chain reaction (PCR). The reaction is carried out in the absence of template using primers (TTAGGG) 5 (SEQ ID NO:1) and (CCCTAA) 5 (SEQ ID NO:2). Staggered annealing of the primers provides a single strand template for extension by Taq polymerase. The primers serve as both primer and template in the early cycles, whereas the newly formed sequences serve as primer and template in subsequent stages of the reaction resulting in a heterogeneous population of molecules consisting of repeat arrays of various lengths.
The DNA synthesized is only used as a probe for hybridization, and the approach thus serves as an alternative to other procedures for labeling of hybridization probes (like end-labeling or tailing). Unlike the approach described here, no surplus short primer is added to the resulting polymers to release a cascade reaction.
A commonly used method for randomly amplifying human DNA is called alu-PCR. This approach utilizes the fact that the human genome contains certain interspersed repeated elements called alu-repeats. These closely similar elements are on the average found once every ca. 10 kb of human genomic DNA. Though the actual distance between two neighboring alu-elements differ significantly along the genome, most of these elements are situated close enough to their neighbors to enable amplification by PCR of the intervening non-alu sequence after hybridization of primers to the alu-sequence.
British Technology Group Ltd has described a similar approach for the detection of Bovine Encephalitis viruses by PCR (WO 9304198 A1). In this case the interspersed repeat is comprised of a tandemly repeated sequence containing six base monomers, each having a sequence exhibiting a dyad symmetry. It is consequently possible to amplify the intervening sequences using only one primer (binding to both strands) rather than the two primers normally employed in other types of PCR, such as the alu-PCR. The fact that the naturally occurring repeat, which is detected by this technique, holds a dyad symmetry entity, gives it a possible chance similarity to one variant of the polymer synthesized by the reactions described here. In such cases where the intervening sequences are sufficiently short, the bovine virus DNA should thus be able to serve as the template for a DNA cascade. However, such a possibility is not recognized in the British Technology Group Patent, which only refers to PCR as the resulting amplification reaction. The chance similarities also imply that both the bovine virus test and some variants of the DNA cascade make use of primers with a dyad symmetry. However, whereas these primers in the DNA cascade are used to construct a molecule, and work on the constructed molecule, the primers in the bovine encephalitis test are only thought of as probes for the diagnostic detection of certain naturally occurring DNA molecules.
In the Japanese unexamined Patent Application, publication no. 04-262799, belonging to Toyobo Co. Ltd., Toshiya & Yutaka have described the formation from a circular DNA molecule of a polymer like the one used as starting material for the present DNA cascade. They obtain the DNA circle by circularizing a designed linear DNA molecule onto a biological DNA molecule, using the circularization as a test for the presence of the relevant biological molecule. After circularization of the test molecule, they add a third DNA molecule capable of binding to the part of the test molecule that did not hybridize with the biological molecule. This third molecule then serves as a primer for rolling circle replication of the circularized test molecule, thus forming a tandem repeat polymer derived from this. In this approach it is not envisioned that the polymer thus generated could be used as the starting material for a DNA cascade. Neither is it suggested that the circularization process could be positioned at the 3′-end of the biological molecule, such that this end could be used as a primer for the rolling circle replication, eliminating the need for the addition of a third DNA molecule to prime this, nor that the reaction could be inverted, such that it is the biological molecule, which is circularized.
SUMMARY OF THE INVENTION
Till now, the very successful techniques for the enzymatic amplification of DNA have been designed to amplify nucleic acid sequences of biological origin to enable studies of or with these sequences. The present invention represents a new strategy, termed a “DNA cascade”, which is to amplify synthetic DNA. The amplification on process may then secondarily be used as a marker in biological analyses, and to co-amplify nucleic acid sequences of biological origin.
The DNA cascade is a technique for the production of multiple partial or complete copies of a preformed template. This is obtained after the initial construction (“linear multiplication reaction”, phase 1) of a suitable template which consists of multiple tandem repetitions of an oligonucleotide unit, each of which can per se serve as a specific starting point for the copying process (the “cascade amplification reaction”, phase 2).
The template for the cascade reaction may be built from two complementary oligonucleotides with an internal repetition unit in a manner similar to that described by J.W. IJdo et al., loc. cit.
However, the template is most conveniently produced by a novel process according to the invention from one oligonucleotide comprising at least one and a halt and preferably two units of a nucleotide sequence showing dyad symmetry.
This process involves repeated denaturation and annealing events to enable the oligonucleotide to grow stepwise by primed synthesis catalyzed by a DNA polymerase in the presence of the necessary nucleoside triphosphates.
This repeated denaturation and annealing can be achieved by thermocycling as illustrated in example 1, but could also be achieved by other means. One possibility would be to incubate the oligonucleotide(s) at the melting point of their duplex form (or slightly above this temperature). This would result in a statistical equilibrium, where a fraction of the molecules at any given time could support chain elongation, and thus polymer growth. In such a setup the temperature cycling would be replaced by a temperature gradient forcing the molecules to become longer and longer to accommodate for the increasing incubation temperature. The advantage of the gradient approach is that it does not require incubations at high temperatures, especially not if the DNA sequences chosen are rich in adenine and thymine. The avoidance of high incubation temperatures may be of advantage if the polymer formation is performed while the oligonucleotides are attached to specific detection reagents like avidin or antibodies, as such molecules tolerate high temperatures poorly.
Thus, in a first aspect the present invention provides a process for producing DNA consisting of multiple tandem repetitions of an oligonucleotide unit, wherein an oligonucleotide comprising at least one and a half unit of a nucleotide sequence showing dyad symmetry is copied stepwise by means of a template- and primer-dependent DNA polymerase in the presence of the necessary nucleoside triphosphates during repeated cycles of denaturation and annealing, the chain elongation taking place each time the annealing results in a frame-shifted hybridization giving rise to duplexes with buried 3′ ends.
The sequence of bases in the oligonucleotide could be freely chosen according to the individual needs, but in order to be able to participate in the polymerization process, the oligonucleotide must consist of at least one and a half copy of the sequence intended to be the repeating unit of the polymer. Furthermore, it may be desirable to construct the oligonucleotide such that it consists of repeats of a sequence showing dyad symmetry, since this makes the sequence complementary to itself and eliminates the need for the inclusion of a second (complementary) oligonucleotide in the polymerization process. Thus, the shortest repeating unit showing dyad symmetry would be two complementary bases, for instance the sequence “AT”. One and a half unit of this sequence would be “ATA”, and the shortest oligonucleotide able to serve as a substrate for the polymerization on its own would thus be a three base oligonucleotide like “ATA”. Any repeating dyad symmetry unit larger than two bases and anyone number of dyad symmetry units larger than one and a half could also be chosen, the only limitation being the technical limitations on the size of the oligonucleotide imposed by the process used to produce the oligonucleotide. Preferably, the starting oligonucleotide comprises at least two units of the nucleotide sequence showing dyad symmetry.
In a particular embodiment of the process for producing the template the nucleotide sequence showing dyad symmetry comprises the promoter region for an enzyme capable of template-dependent DNA or RNA synthesis without the need for a primer and the complementary repeat of said region. The presence of such a promoter region in each oligonucleotide unit of the template may be of advantage in the carrying out of the subsequent cascade phase as explained below.
In another particular embodiment of the above process any nucleotide sequence to be amplified is inserted between the copies of the nucleotide sequence showing dyad symmetry in the starting oligonucleotide. If such inserted nucleotide sequence comprises the promoter region for an enzyme capable of template-dependent DNA or RNA synthesis without the need for a primer, the same result is obtained as in the first particular embodiment above.
A nucleic acid template consisting of multiple tandem repetitions of an oligonucleotide unit can also be produced by another novel process according to the invention which involves circularization of one oligonucleotide so that it has no end and thus can act as a template for an endless copying process catalyzed by an enzyme that displaces rather than digests DNA or RNA occupying the part of the circular oligonucleotide which it is about to copy producing a large molecule being a multimer of the oligonucleotide.
Thus, in a second aspect the present invention provides a process for producing nucleic acid consisting of multiple tandem repetitions of an oligonucleotide unit, wherein a circular oligonucleotide comprising at least one copy of said unit is used as a template for an endless copying process by means of a nucleic acid polymerase, which is capable of strand displacement and is substantially without 5′-3′ exonuclease activity, in the presence of the necessary nucleoside triphosphates and, if necessary, a primer capable of binding to some portion of the oligonucleotide.
The circularization process can be of two kinds, as the reaction can be designed to circularize any of the two strands on the other. If using a synthetic sequence and a biological sequence, one could thus choose to circularize the biological sequence on the synthetic or the synthetic on the biological, all depending on the design of the experiment. Likewise, one could either circularize the strand to be circularized at the 3′-end of the template strand, such that this could serve also serve as primer for the polymer formation, or one could do the circularization away from the 3′-end of the template, such that the addition of a separate primer for the rolling circle replication would be necessary.
When a polymerase capable of template- and primer-dependent DNA or RNA synthesis is used, the copying is started from a primer binding to some portion of the circular oligonucleotide.
With a view to a subsequent cascade reaction the polymerase is preferably a template- and primer-dependent DNA polymerase, and it may be of advantage that the circular oligonucleotide comprises a DNA sequence showing dyad symmetry, and the primer has the same DNA sequence.
When a template-dependent RNA polymerase without the need for a primer is used, the copying is started from a promoter region incorporated in the circular oligonucleotide and being recognized by the polymerase.
In that case, if it is desired to carry out a subsequent cascade reaction, it is necessary to produce a DNA multimer from the resulting RNA multimer by means of a reverse transcriptase and a DNA primer.
For purposes of monitoring the linear multiplication reaction and detecting the multimer product it may be useful that the nucleoside triphosphates present are labeled. Such label can for example be an enzyme, a radioactive isotope, a fluorescent compound, a chemiluminescent compound, a bioluminescent compound, a metal chelate or a hapten detectable by a specific secondary reaction.
The cascade amplification reaction comprises a copying of the template in an enzyme catalyzed process that originates from multiple repeating units in the template, thus making it possible to produce multiple copies of any segment of the template. To obtain this it is necessary to use enzymes that displaces rather than digests DNA or RNA occupying the part of the template which it is about to copy. As the sequences of the produced copies are both identical and complementary, they are able to aggregate forming large complexes with a decreased mobility relative to the individual molecules.
Accordingly, in a second aspect the present invention provides a cascade nucleic acid amplification reaction, wherein a great number of partial and complete DNA or RNA copies of a DNA template consisting of multiple tandem repetitions of an oligonucleotide unit is produced by means of a nucleic acid polymerase, which is capable of strand displacement and is substantially without 5′-3′ exonuclease activity, by contacting the template with said nucleic acid polymerase in the preserve of the necessary nucleoside triphosphates and, if necessary, a primer capable of binding to the oligonucleotide unit, the polymerase thus synthesizing DNA or RNA originating from, ideally, each repeating oligonucleotide unit in the template.
If any part of the repeating oligonucleotide unit corresponds to the promoter of an enzyme capable of template-dependent DNA or RNA synthesis without the need for a primer as a starting point for the process, like the T3, T7 or SP6 RNA polymerase, the cascade phase can be induced by the simple addition of this enzyme and the necessary nucleoside triphosphates to the single-stranded or double-stranded template, preferably the double-stranded template.
If this is not the case, a primer capable of binding to the repeating oligonucleotide unit is needed along with a suitable enzyme that can synthesize DNA or RNA from the appropriate nucleoside triphosphates in a template- and primer-dependent reaction and has the aforementioned ability to induce strand displacement. In this case the strands of the template must first be separated so that the primer is able to hybridize to each strand. Suitable DNA polymerases of this kind are e.g. the Klenow fragment of DNA polymerase I, preparations of the Taq polymerase without exonuclease activity or the T4 DNA polymerase.
If the DNA template is produced from a circular oligonucleotide by means of a DNA polymerase starting from a primer binding to some portion of the circular oligonucleotide, the cascade reaction may be carried out simultaneously with the template formation by adding a primer binding to at least a portion of the complementary oligonucleotide units comprising the template.
In this case, as mentioned previously, it is advantageous that the starting circular oligonucleotide comprises a DNA sequence showing dyad symmetry, and the primer has the same DNA sequence, as then both the template formation and the cascade reaction therefrom will take place using the same single primer.
When the nucleic acid polymerase is a DNA polymerase, the synthesized strands displaced from the template are also DNA, and the cascade reaction proceeds further from the repeated oligonucleotide units of the newly synthesized DNA strands.
In a particular embodiment of such a cascade reaction the time of conducting the cascade reaction is adjusted to the number of repeated units in the template and, possibly, the concentration of primer in such a way that the copying of the template and the newly synthesized DNA strands does not proceed to the ends thereof, so that the displaced strands remain attached to the template, forming a large web of interconnected strands.
When the nucleic acid polymerase is a RNA polymerase, the synthesized strands displaced from the template are RNA, and the cascade reaction produces a great number of single-stranded RNA molecules which hybridize to each other forming a large immobile network.
The synthesized RNA molecules will not be copied further by the RNA polymerase, but if further copies are desired, it is possible to proceed as follows: The produced network of hybridized RNA molecules is denatured, annealed to complementary oligonucleotides suitable as primers for cDNA synthesis and copied into cDNA strands by means of a reverse transcriptase, after which the cascade reaction proceeds further from the repeated oligonucleotide units of the cDNA strands.
Also in the cascade reaction it may be useful for purposes of monitoring the reaction or detecting the product or products that the nucleoside triphosphates present are labeled. Again, such label can for example be an enzyme, a radioactive isotope, a fluorescent compound, a chemiluminescent compound, a bioluminescent compound, a metal chelate or a hapten detectable by a specific secondary reaction.
An application aspect of the present invention provides a method of detecting a target molecule or group at a specific site, wherein
a) a detector molecule that binds specifically to the target is attached to an oligonucleotide capable of taking part in a reaction to form a DNA template consisting of multiple tandem repetitions of said oligonucleotide,
b) the oligonucleotide with attached detector molecule is contacted with the target site, and oligonucleotide with attached detector molecule not bound to target is removed,
c) a reaction to form a DNA template consisting of multiple tandem repetitions of the oligonucleotide bound to the detector molecule is carried out, and
d) the target is detected by detection of the bound amplified nucleic acid.
In this method it will often be expedient that further a cascade reaction as previously described is carried out before detecting the target.
In another embodiment of this method
a) a detector molecule that binds specifically to the target is attached to a DNA template consisting of multiple tandem repetitions of an oligonucleotide unit,
b) the template with attached detector molecule is contacted with the target site, and template with attached detector molecule not bound to target is removed,
c) a cascade reaction as previously described is carried out, and
d) the target is detected by detection of the bound amplified nucleic acid.
When the method comprises a cascade reaction, the presence of a large web of nucleic acid strands may be visible or detectable on its own, but usually the nucleoside triphosphates used in the process for producing the DNA template and, possibly, in the cascade reaction are labeled, and the target is detected by detecting the label.
The label on the labeled nucleoside triphosphates can for example be an enzyme, a radioactive isotope, a fluorescent compound, a chemiluminescent compound, a bioluminescent compound, a metal chelate or a hapten such as biotin detectable by a specific secondary reaction.
If the product of the detection reaction shall appear at a certain localization, the target molecules or groups to be detected should be bound to a specific site either before or after the reactions according to this invention take place. For example, they may be fixed to a solid surface, or they may be confined within a narrow space such as an organic cell.
A practical use of this aspect of the invention is the one wherein the target is a specific antigen, and the detector molecule is an antibody to said antigen. Another is the one wherein the target is a specific carbohydrate molecule or group, and the detector molecule is a lectin binding thereto. Yet another is the one wherein the target is a specific nucleic acid sequence, and the detector molecule is a DNA or RNA probe which hybridize specifically to the target sequence.
A further application aspect of the present invention provides a process for the amplification of a particular DNA fragment, wherein a first oligonucleotide is added to both ends of one copy of said DNA sequence and a second oligonucleotide complementary to the first one is added to both ends of another copy of said DNA sequence, and the resulting DNA sequences are copied stepwise by means of a template- and primer-dependent DNA polymarase in the presence of the necessary nucleoside triphosphates during repeated cycles of denaturation and annealing, the chain elongation taking place each time the annealing results in a frame-shifted hybridization giving rise to duplexes with buried 3′ ends.
In another embodiment of this amplification process, a first oligonucleotide is added to the 5′ end and a second oligonucleotide complementary to the first one is added to the 3′ end of one copy of said DNA sequence and vice versa with another copy of said DNA sequence, and the resulting DNA sequences are copied stepwise by means of a template- and primer-dependent DNA polymerase in the presence of the necessary nucleoside triphosphates during repeated cycles of denaturation and annealing, the chain elongation taking place each time the annealing results in a frame-shifted hybridization giving rise to duplexes with buried 3′ ends.
In yet another embodiment of this amplification process, at least one unit of an oligonucleotide showing dyad symmetry is added to both ends of said DNA sequence, and the resulting DNA sequence is copied stepwise by means of a template- and primer-dependent DNA polymerase in the presence of the necessary nucleoside triphosphates during repeated cycles of denaturation and annealing, the chain elongation taking place each time the annealing results in a frame-shifted hybridization giving rise to duplexes with buried 3′ ends.
In each of the above three embodiments it may be expedient that the oligonucleotide units added to the ends of the particular DNA sequence are designed to contain restriction enzyme recognition sites bordering said DNA sequence.
In still another embodiment of the amplification process the particular DNA sequence to be amplified is either circularized or inserted into a circular oligonucleotide, and the resulting circular DNA is used as a template for an endless copying process by means of a nucleic acid polymerase capable of strand displacement and substantially without 5′-3′ exonuclease activity in the presence of the necessary nucleoside triphosphates and, if necessary, a primer capable of binding to some portion of the oligonucleotide.
In this embodiment it may be expedient that the particular DNA sequence is inserted in a site of the circular oligonucleotide producing restriction enzyme recognition sites bordering said DNA sequence.
Each of the above described embodiments of the amplification process will produce by far the largest amplification when the process further comprises a cascade reaction as previously described.
Also in this amplification aspect of the invention it may be useful for monitoring or detection purposes that the nucleoside triphosphates used in the process are labeled.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the perfect match of two copies of one oligonucleotide comprising two units of dyad symmetry as well as the frameshifted annealing of the strands and DNA synthesis after the first denaturation of the double strand.
Similarly, FIG. 2 illustrates the perfect match of an oligonucleotide with internal repetitions and its complementary oligonucleotide as well as the frameshifted annealing of the two strands and DNA synthesis after the first denaturation of the double strand.
FIG. 3 illustrates the co-amplification of a DNA sequence of twelve “irrelevant” bases between two units of a dyad symmetry sequence.
FIG. 4 is a diagram illustrating an endless copying from a circular oligonucleotide. (1) is a linear oligonucleotide; (2) is the circularized oligonucleotide; (3) illustrates the copying of the circular oligonucleotide starting from a primer or a promoter at the 5′ end; and (4) illustrates the strand displacement and continued copying after one turn of the oligonucleotide.
FIG. 5 illustrates a cascade amplification reaction from a DNA template consisting of multiple tandem repetitions of a dyad symmetry oligonucleotide unit using the dyad symmetry unit as a primer. The primer will hybridize to numerous complementary sequences in the template strand, and as the used DNA polymerase is capable of strand displacement and has no significant 5′-3′ exonuclease activity, strand displacement will occur when the DNA synthesis reaches a site already occupied by a synthesized strand. Thus the DNA synthesis continues along the template strand, while more primer sequences bind to the displaced strands giving rise to the synthesis of new strands displacing each other.
FIG. 6 illustrates the attachment of an oligonucleotide comprising repeated units of a dyad symmetry nucleotide sequence to an antibody which binds to a specific antigen fixed to a solid surface with a view to a subsequent multiplication and, optionally, cascade reaction to detect the antibody.
DETAILED DESCRIPTION OF THE INVENTION
The theoretically most productive embodiment of the invention is as follows:
i) The template is produced by polymerization from a dyad symmetry of a short repeating oligonucleotide unit to make it contain as many dyad symmetry sequences as possible.
ii) The cascade phase produces multiple DNA copies of the template. Due to the dyad symmetry nature of the sequence each of the multiple copies will have a sequence composition identical to that of the template and will thus be able to serve as template for the synthesis of multiple new copies that each can serve as a template for the synthesis of multiple new copies (and so on). (If the nucleic acid produced in the process is RNA, it would be necessary with the enzymes available today to convert this to DNA with a second enzyme (a reverse transcriptase) to make it a suitable template for new rounds of copying.)
This embodiment is described in greater detail in the following.
The DNA cascade is a two-phase reaction for the production of large amounts of DNA with a specific base sequence. In phase 1 multimers of a chosen oligonucleotide sequence are generated. In phase 2 this multimer structure (the template) is amplified to an amount several orders of magnitude larger than the amount of starting material. The linking of the two phases results in an effect far beyond what could be achieved with each of the two reactions individually. The DNA synthesized in phase 2 could serve as starting material for a second phase 1 or a second phase 2. The different steps can thus be repeated and combined according to the specific needs. In both phases several variants could be imagined. In the following an account of the principle of each stem will be given, along with a short mention of main variants and a presentation of possible applications.
Formation of Multimers
The multimer template formation by sequential growth from an oligonucleotide of dyad symmetry can be illustrated with the oligonucleotide
GAAATTTCGAAATTTC (or (GAAATTTC) 2 ), (SEQ ID NO:3)
which is a direct repeat of the dyad symmetry GAAATTTC. Two molecules of this oligonucleotide can hybridize either with a perfect match or in a frameshifted position where only half of each molecule basepairs (FIG. 1 ). In the latter situation the duplexes will have either buried or free 3′ ends, representing a frame shift either to the right or to the left. If a DNA polymerase and nucleoside triphosphates are present, buried 3′ ends will be extended resulting in the growth of that DNA strand by half the size of the oligonucleotide employed. Thus, on the average 25% of the oligonucleotides will increase their length by 50%. If successive rounds of denaturation and annealing/chain elongation are performed, the molecules will keep increasing in size at a steadily increasing speed (There are two reasons why the rate of growth will increase. One is that a heterogeneous population of molecules is generated, which increases the frequency of frameshifting. The other is that as the molecules get longer, so do the possible frameshifts and thus the resulting growth.), until a level is reached where the reaction decreases in efficiency due to the fact that DNA polymerases can only synthesize some kilobases of DNA in vitro. By then our original 16mer has grown to a size of several kilobases.
A similar reaction could be obtained with two oligonucleotides having the sequence (GAAA) n and (TTTC) n (FIG. 2 ). Such a polymerization reaction from two oligonucleotides has previously been described by J. W. IJdo et al., loc. cit., and was shown to be able to generate 25 kilobase molecules from short oligonucleotides.
The principle as such should not be affected by the placing of an “irrelevant”πsequence between the initial copies of the growing oligonucleotide. (By “irrelevant” in this context is meant that the sequence on its own would be unable to engage in the reactions according to this invention). Thus, the oligonucleotide
GAAATTTC[“irrelevant” sequence]GAAATTTC
should grow to generate the sequence
(GAAATTTC[“irrelevant” sequence]) n GAAATTTC
(FIG. 3 ).
The advantage of adding the “irrelevant” sequence would be to have it co-amplified along with the amplifying oligonucleotide. The oligonucleotide would thus serve as carrier for the amplification of something else. The cost will of course be that as the size of the amplification unit increases, the number of copies in each polymer decreases since the total size of the polymer is fixed. The lower the number of units per polymer, the less DNA could be generated in the next phase where the maximum degree of amplification is primarily determined by the number of repeating units in each polymer.
In case of multimer template formation from a circular oligonucleotide, the multimer can be generated without repeated denaturation and annealing (FIG. 4 ). This requires the use of a polymerase capable of strand displacement and substantially without 5′-3′ exonuclease activity as described for the cascade phase below and with kinetics identical to those described there. Also, the starting oligonucleotide should be bigger than is needed for multimer template formation from a linear molecule of dyad symmetry. However, the exact minimum size cannot be stated, as it will depend upon the sequence of the oligonucleotide and the size of the enzyme used to copy the circular DNA. The rigidity of the DNA depends upon the sequence of bases, and the more rigid it is, the longer the oligonucleotide needs to be in order to be bent into a circle. Furthermore, this circle must be big enough to enable the DNA polymerase to operate on it. If the original oligonucleotide is not big enough to fulfill these requirements, it can be elongated as described in the previous paragraph, until it has reached a sufficient size. Apart from the size requirements, the circularization variant only requires that the molecule to be circularized has a 5′-phosphate group and a 3′-hydroxy group as well as the addition of a DNA or RNA ligase under suitable reaction conditions including the presence of an energy-rich molecule like ATP to donate the necessary energy for the covalent linking of the ends. If the circular oligonucleotide has to be fixed at a certain site, it must be connected to a detector molecule, contain a detector molecule or contain a moiety capable of attaching to a detector molecule.
The possibility of forming a polymer from a circular template may be used to identify molecules capable of forming circles when complemented with a suitable template, or capable of serving as templates for circularization of the complementing DNA. The existence of a certain biological molecule can thus be detected through its ability to induce circularization of a linear DNA molecule added to it, and the circularization detected through the ability of a third DNA molecule to bind to the circle initiating rolling circle replication as described in the Toyobo patent, loc. cit.
However, the circularization may more conveniently be performed towards the 3′-end of the template, such that this end can serve as a primer for the rolling circle replication. Not only does this approach eliminate the need for the addition of an extra primer, it also keeps circles erroneously formed at cross reacting sites from being copied, unless they by chance coincide with a 3′-end. This approach also has the further advantage that the polymer would be covalently linked to the 3′-end which is detected. Thus, if the circle is formed at a site within a chromosome, the polymer will be a continuation of the chromosomal DNA at that site, and if the circle is formed on DNA captured in a microtitre well, on magnetic beads or otherwise, the polymer will be a continuation of the captured DNA. As a result of this, the polymer is not only specifically synthesized at the relevant site, but also very efficiently retained here.
The formation of the polymer can be directly detected if it is synthesized from labeled nucleotides, but more specificity and sensitivity would be obtained by adding a separate detection step, which could be a DNA cascade on the polymer, or possibly other approaches like PRINS or FISH. A prerequisite for this type of reaction is that the DNA studied has a suitably located 3′-end. If such an end is not naturally available, it may be generated artificially e.g. by digestion with a suitable restriction enzyme.
A further aspect of this assay is that it is not only sensitive to the sequence of the DNA template, but also to the form of it (broken (with a 3′-end) or continuous (no 3′-end)). It should thus be possible to determine not only if and where a certain target sequence is present, but also whether it is broken or not. Such breaks could result from a variety of enzymatic actions (e.g. topoisomerases) and pathological processes (e.g. chromosome breaks in cancer).
Reverting the setup of the assay, such that it is the DNA in the sample that is circularized on the DNA added, has the consequence that it is the DNA in the sample which is copied in the rolling circle replication. Consequently, the sequence composition of the DNA in the polymer will reflect that of the sample and a subsequent cascade reaction on the polymer can be released with primers inside the segments used for circularization, such that any “wrong” circle formed would be undetected, as it could not bind the cascade primers. Furthermore, the DNA synthesized in the cascade reaction would also correspond to the sample, and could on its own be used for analytical purposes (used as probe, sequenced etc.).
A circular oligonucleotide as described above can also be used directly as a template for the cascade phase below, if such is desired.
The Cascade Phase
If the original oligonucleotide is added to the polymers, it will bind at numerous positions along the elongated DNA, since what we have is a long polymer containing up to several thousand tandem copies of the original oligonucleotide. If the annealing occurs in the presence of labeled nucleotides and a DNA polymerase substantially without 5′-3′ exonuclease activity, these hybridizations will result in a similar number of priming events each generating a labeled partial copy of the polymer. Since the DNA polymerase has no significant exonuclease activity, strand-displacement will occur when the DNA synthesis reaches a site already occupied by an oligonucleotide, thus making it possible to produce multiple copies of the same segment of the polymer (FIG. 5 ).
As seen in FIG. 5, the single-stranded DNA that is produced by the strand-displacement also has the potential to bind new oligonucleotides (which give rise to new strands displacing each other). In principle this process could go on for ever (and at a steadily increasing speed, since the number of new single strands generated exceeds the number of strands used to generate them), generating at maximum m n molecules by n rounds of strand displacement from a polymer containing m copies of the amplifying oligonucleotide. In practice the reaction is likely to slow down after some time since the new strands will get shorter and shorter with each generation. However, from one polymer molecule containing a thousand copies of the original oligonucleotide (m=1000), 10 16 new molecules will likely be produced, if the reaction is run to completion (n reaching maximum value).
If the size of the original oligonucleotide is increased by inclusion of an “irrelevant” sequence as mentioned above this will of course also be produced in large amounts, though the total amplification will be decreased, and with very long additions only a few hundred molecules may be generated from each polymer.
In this case the reactions could be repeated, either phase 2 alone using all the new strands as templates for a second cascade reaction, or the complete reaction letting the new strands elongate themselves prior to a new cascade step. Repeating the complete reaction p times would at maximum result in a (m n ) p fold amplification.
Other ways of enhancing the cascade reaction would be by pre-reacting the polymer with the cascade releasing oligonucleotide(s) for a while before the DNA polymerase is added, thus ensuring that all potential binding sites will be used in the first round of DNA synthesis, and use of a degradable primer as described in the Becton Dickinson and Boehringer Mannheim patents (loc. cit.), to obtain a multitude of priming events from each site, or a combination of these approaches.
Alternatively, the recognition site of a RNA polymerase like the T7 RNA polymerase could be included in the amplification unit and the enzyme added at the end of the reaction as cascade amplifier (the T7 RNA polymerase will upon binding generate up to 40 RNA copies of the DNA sequence next to the recognition sequence, so if the original unit is amplified 10 fold during the polymerization phase and another 100 fold during the cascade phase the total amplification would then be 10×100 ×40=4000 fold).
Promoter sequences can be polymerized as illustrated here with the promoter for the T7 RNA polymerase.
The cascade phase can not only be released with a primer-dependent polymerase, but also with a promoter-dependent. polymerase; and the nucleic acid produced may be RNA rather than DNA as illustrated here for the promoter-dependent RNA-producing enzyme T7 RNA polymerase. The sequence of the T7 promoter is
CCCTATAGTGAGTCGTATTA (SEQ ID NO:13).
The shortest dyad symmetry constructed from this sequence is:
CCCTATAGTGAGTCGTATT:AATACGACTCACTATAGGG (SEQ ID NO:14)
(“:” indicates the axis of symmetry). Oligonucleotides containing at least one and a half unit of this dyad symmetry could be polymerized into a double stranded polynucleotide, each strand having the sequence
(CCCTATAGTGAGTCGTATTAATACGACTCACTATAGGG) n (SEQ ID NO: 15).
If, for instance, “n” is 100, this means that each strand contains 100 potential binding sites for the T7 RNA polymerase. To obtain binding of the polymerase it is not necessary that the DNA strands are separated (denatured) by heat or otherwise. It is sufficient to add the polymerase and RNA precursors (nucleoside triphosphates) to the polymer according to one of the many protocols describing RNA synthesis from a T7 promoter. The polymerase will then bind at multiple sites along the DNA strand providing high speed multifocal RNA synthesis.
This type of reaction might be especially suited for applications where it is of particular importance that the nucleic acids produced in the reaction are very precisely retained at the site of synthesis (e.g. gene localization on metaphase chromosomes). The reason for this is that the single stranded RNA molecules produced are self-complementary, just as the DNA strands from which they are copied. Together with the high concentration and the low complexity of these molecules, this will cause the strands to hybridize to each other almost immediately, forming a network with a size and density that would make it unlikely to diffuse away from the site of synthesis. Theoretically, the network could reach such a size and density that it precipitated, which would leave it completely unable to move unless subjected to some mechanical force (like vigorous shaking).
The network formed could not bind the T7 RNA polymerase for the production of further RNA strands as this enzyme only binds to DNA. If such is desired, it is necessary to copy the RNA molecules into cDNA molecules. This can be done from nucleoside triphosphates by a reverse transcriptase and requires that the network is denatured (by heating or otherwise) and annealed to complementary oligonucleotides that can serve as starting points (primers) for the DNA synthesis.
Possible Applications
Amplifications without Added “Irrelevant” DNA
In this situation the oligonucleotide(s) only amplify itself (themselves). Since what is generated is only large amounts of the chosen short oligonucleotide and not some “biological” molecule, the reaction is particularly suited for detection purposes.
A prerequisite for this type of use is that the molecules can be brought to stay at a relevant site. Initially, this can be obtained by fixation of the polymer template for the cascade reaction to a detector molecule capable of binding specifically to the relevant site. This fixation may be obtained either by a chemical reaction between reactive groups on the two molecules or by an affinity reaction where the template contains a moiety that will bind specifically to the detector molecule. Thus, if the detector molecule is avidin or streptavidin, the template can be specifically attached thereto, if it contains a biotin moiety. Similarly, if the detector molecule is an antibody, the template can be attached specifically thereto, if it contains an antigen recognized by that antibody. This binding of the template may take place prior to, concurrently with or after the binding of the detector molecule to the relevant target. If preferable, an oligonucleotide capable of taking part in the formation of the polymer template may be attached instead of the template, and the template may then be formed at the detector molecule.
If the polymer formation starts from a circularized oligonucleotide, the circle can be used to cause the covalent binding of the polymer to the target detected, or serve as an anchoring point for the polymer, with the polymer ending in the circle and the circle encircling the target.
Once the template has been attached to the relevant site, the cascade reaction may be conducted. As can be deduced from FIG. 5, the strand displacement occurring in this phase will generate single-stranded molecules which are either attached directly or indirectly to the polymer template or are attached to other similar molecules in a large network which is unable to move around due to its size. The nucleic acids synthesized during the cascade phase will thus stay with the polymer that was attached to the relevant site. Depending upon the experimental setup this retention of the product can be enhanced by the characteristics of the relevant site. Thus, for instance, if the reaction is performed within a cell, the skeleton and membrane of the cell will serve to increase the retention of the product.
If the substrate for the nucleic acid synthesis is labeled nucleotides, the synthesized nucleic acids will be labeled. Thus, the 10 16 molecules generated from one precursor molecule in the example above could be labeled. This number of labeled molecules is far above the detection limit in most laboratory reactions. Thus, if the initiating oligonucleotides are fixed to a specific detector molecule (like an antibody to an antigen of interest) the presence (binding) of this detector molecule could be visible even if only a single molecule is bound to the target (FIG. 6 ).
We would thus have a detection system with the highest possible sensitivity, since it could detect the existence of single entities. For most applications this level of sensitivity would be meaningless as it would be difficult to tell specific binding of single detector molecules from the unavoidable non-specific binding of these molecules. However, the high level of sensitivity would ensure that the sensitivity would always be sufficient.
It should be noted that the polymerization step is a non-specific reaction in the sense that any oligonucleotide with the ability to participate in such a reaction could do so under the right condition. Thus, a number of different oligonucleotides could be polymerized in one single reaction. By contrast, the cascade step is a specific step dependent on the addition of a specific oligonucleotide (or enzyme) to release the cascade. This could be utilized for differential staining of multiple targets. If a number of different oligonucleotides were attached to a corresponding number of antibodies and these were bound to their corresponding antigens, all the oligonucleotides could be polymerized in one single reaction. Subsequently, each polymer could be used as template for a specific cascade reaction released by the relevant oligonucleotide. Thus, if the first cascade was released with a red label, the second cascade with a green label and the third cascade with a blue label, the first target would appear in red, the second in green and the third in blue.
Co-Amplification of “Irrelevant” DNA
As described previously some other DNA sequence could be placed in the array of annealing DNA. This “irrelevant” DNA could in principle be of any type, as long as the size is not excessive, making the polymerization in phase 1 impossible. Thus, the DNA multiplication and, possibly, cascade could be used for the generation of large amounts of some interesting DNA sequence just as the polymerase chain reaction (PCR) and cloning. The DNA generated could then be used for whatever purposes DNA is used for. It could for instance be labeled during the synthesis and used as a hybridization probe, or it could be characterized by sequencing or otherwise.
To carry out the amplification of this DNA it is of course necessary to add the annealing sequences to the ends of the DNA of interest. This could be done in either of a number of ways. The sequences could be ligated directly to the ends of the DNA by standard ligation procedures, or it could be contained within a vector used for cloning of the DNA, for instance flanking the polylinker found in most modern vectors. Whatever method is chosen, the end result would be a DNA sequence capable of self-amplification through a DNA multiplication and cascade. If it is necessary to release the amplified “irrelevant” DNA from the amplifying sequences after the amplification, the annealing DNA may be designed to contain recognition sites for restriction enzymes.
If multiplication by means of two complementary oligonucleotide sequences is used, this may be done in two different ways. Either a first oligonucleotide, e.g. ATCG, may be added to both ends of one batch of the “irrelevant” DNA to be amplified, and a second oligonucleotide complementary to the first one, in casu CGAT, added to both ends of another batch of the “irrelevant” DNA, the resulting DNA sequences hybridizing and polymerizing as follows:
5′ ATCG[irrelevant]ATCG 3′→←3′ TAGC[irrelevant ]TAGC 5′
Or the first oligonucleotide may be added to the 5′ end and the second oligonucleotide to the 3′ end of the first batch of “irrelevant” DNA, while the first oligonucleotide is added to the 3′ end and the second oligonucleotide to the 5′ end of the second batch of “irrelevant” DNA, the resulting DNA sequences hybridizing and polymerizing as follows:
5′ ATCG[irrelevant]CGAT 3′→←3′ GCTA[irrelevant]TAGC 5′
If multiplication by means of one oligonucleotide showing dyad symmetry is used, this dyad symmetry oligonucleotide, e.g. GAAATTTC, is added to both ends of the “irrelevant” DNA, the resulting DNA sequence hybridizing and polymerizing as follows:
5′ GAAATTTC[irrelevant]GAAATTTC 3′→←3′ CTTTAAAG[irrelevant]CTTTAAAG 5′
In these embodiments of the multiplication reaction the first step of hybridization and polymerization will produce complementary copies of the “irrelevant” DNA; the second step will produce actual copies of the “irrelevant” DNA and so forth. The result will be a template comprising shifting actual and complementary copies of the desired DNA. A subsequent cascade reaction copying both the resulting template and the copies of the template will thus produce a multitude of both actual and complementary copies of the desired DNA.
On the other hand, if the multiplication reaction is carried out by endless copying of a circular DNA incorporating the “irrelevant” DNA, the resulting template will comprise multiple complementary DNA or RNA copies of the desired DNA. If the template is DNA, a subsequent cascade reaction will in the first instance produce actual copies of the desired DNA, in the next instance complementary copies thereof and so forth. If the template is RNA, this may by reverse transcription be copied into cDNA comprising actual copies of the desired DNA, and a subsequent cascade reaction will in the first instance produce complementary copies of the desired DNA, in the next instance actual copies thereof and so forth. In every case the end result will be a multitude of both actual and complementary copies of the desired DNA.
Co-amplification reactions could of course also be used for detection purposes by labeling as described previously. The amount of DNA generated in the cascade step would be much lower, but this may be affordable. Also, the larger size of the amplification unit might increase the retention at the site of synthesis compensating for the lower overall yield.
Furthermore, with the co-amplification of some other DNA it would be possible to release the cascade with an oligonucleotide primer hybridizing to some sequence within this DNA rather than to the oligonucleotide sequence used for the polymerization. This would likely increase the specificity of the reaction further.
Similarly, the detector molecule could be present as an “irrelevant” sequence directing the amplifying construct to a site capable of hybridizing with the “irrelevant” sequence thus binding the cascade reaction to that site.
EXAMPLES
Example 1
Formation of a Polymer From a Tandem Repeat of a dyad Symmetry Sequence.
The sequence
5′-ACAAATTTGT-3′ (SEQ ID NO:16)
has a dyad symmetry. The oligonucleotide
5′-ACAAATTTGTACAAATTTGT-3′ (SEQ ID NO: 17)
contains two repeats of this dyad symmetry and can be elongated to an apparent size of about 20 kb (as estimated by neutral agarose gel electrophoresis) by the reaction described here. In this example the resulting polymer is labeled with digoxigenin, as digoxigenin-labeled dUTP is added to the reaction. The digoxigenin-dUTP can of course be omitted or replaced with dTTP.
A similar elongation is achieved if the oligonucleotide is synthesized with a biotin molecule attached to the 5′-end, making it possible to fix the oligonucleotide or its polymer to avidin, if such is desired.
The 10 μl taken out each ten cycles can be used to monitor the progress of the polymer formation. It appears that most of the elongation occurs in the last incubation, as predicted from the theoretical considerations. It also appears that the polymers vary more in size as they become longer, which is also as expected.
Procedure
Mix the following in a final volume of 20 μl:
1-10 ng (about 1 pmol) oligonucleotide
2 μl glycerol
2 μl 10×Taq-buffer (supplied by the supplier of Taq polymerase)
2 nmol each of dATP, dCTP, dGTP and dTTP
500 pmol dig-11-dUTP (Boehringer Mannheim)
2U Taq polymerase (Boehringer Mannheim)
Water to 20 μl
Incubate in a thermocycler for 10 cycles at:
30° C. for 2 minutes
50° C. for 1 minute
70° C. for 1 minute.
Then transfer 10 μl of the mixture to a new reaction and add the following mixture:
1 μl glycerol
1 μl 10 ×Taq-buffer
2 nmol each of dATP, dCTP, dGTP and dCTP
500 pmol dig-11-dUTP
2 U Tag polymerase
Water to 10 μl.
Incubate in a thermocycler for 10 cycles at:
40° C. for 2 minutes
65° C. for 2 minutes
90° C. for 1 minute.
Then transfer 10 μl of the mixture to a new reaction and add the following mixture:
1 μl glycerol
1 μl 10×Taq-buffer
2 nmol each of dCTP, dGTP, dTTP
4 nmol dATP
500 pmol dig-11-dUTP
4 U Taq polymerase
Water to 10 μl.
Incubate in a thermocycler for 10 cycles at:
50° C. for 2 minutes
70° C. for 10 minutes
90° C. for 1 minute.
After this the polymer had reached a size of about 20 kb in the experiments recited here. Repeating the last incubation twice did not result in any further apparent increase in polymer size.
Example 2
The gene mutated in Cystic Fibrosis can be stained in preparations of metaphase chromosomes and interphase nuclei
In this protocol an oligonucleotide probe is circularized and ligated on the normal variant of the Cystic Fibrosis gene in a preparation of fixed cells from a healthy human donor. After ligation a second primer is added. This primer hybridizes to the part of the circle not hybridizing with the genomic DNA and initiates polymer formation through rolling circle replication of the circle. After this the same primer is added again, but this time together with a non-complementary primer capable of hybridizing with the polymer. Together these two primers then generate a cascade reaction on the polymer. With the inclusion of digoxigenin-labeled dUTP in the reaction mixture, this cascade reaction can subsequently be made visible by incubation with fluorochrome-labeled antidigoxigenin antibody.
At sites where all reactions work optimally the stamina in metaphase chromosomes looks like a little down, situated in the middle of the long arm of chromosome 7 . However, none of the steps works to 100% in all cells, so the appearance will vary from cell to cell. If the first oligonucleotide does not hybridize to the target sequence or if it is not ligated after hybridization, no staining can be generated. The same is the case if the hybridization of the polymer-generating oligonucleotide or the rolling circle replication fails. Where all of these reactions have worked, the cascade can be released. The amount of (labeled) DNA made in these reactions is expected to vary depending on how much the individual polymers increased in the preceding step (the longer the polymer, the more cascade product) and depending on spatial conditions at the individual site (how much DNA can be accomodated). In accordance with this the appearance of individual chromosomes 7 after the reaction varies from no signal to a dot-like signal to a down-like signal; and of the two chromosomes 7 in a single metaphase none, one or both may be stained.
Most interphase nuclei also contain stained sites. However, since the nuclei, unlike the chromosomes, present no morphological features to help determine if the staining is located at the right site, this result is more difficult to interpret.
Procedure
Make a fresh spreading of cells fixed in methanol and acetic acid (3:1) on a microscope slide. To facilitate access to the hybridization sites, it is important that the chromosomes are well spread and not embedded in dense cytoplasm.
Prepare the following mixture for hybridization and ligation of the Cystic Fibrosis probe:
2.5 pmol probe (5′-p-AAGATGATA(T) 4 CTTTAATG(T) 16 ATAATGTTAA GTGACCGGCAGC(A) 4 TG(T) 16 CATCATAGGAAACACCA-3′) (SEQ ID NO:18)
5 μl 10×Tth ligase buffer (1×buffer: 20 mM Tris.HCl pH 9.0, 100 mM KCl 10 mM MgCl 2 , 1 mM EDTA and 0.1% “Triton® X-100”)
10 μl 10 mM NAD
5 μg sonicated and denatured salmon sperm DNA
5 μg BSA
5 μl glycerol
12.5 U Tth DNA ligase
water to 50 μl.
Add the mixture to the slide and spread with a coverslip. Incubate at 92.5° C. for 2.5 minutes (to denature the genomic DNA) and then at 55° C. for 30 minutes (to hybridize and ligate probe).
Then wash in 30% formamide, 2×SSC pH 7.0 (1×SSC: 150 mM NaCl, 15 mM sodium citrate) at 42° C. for 10 minutes and in 2×SSC at 55° C. for 10 minutes to remove both free and unligated probes.
Dehydrate the slide in an ethanol series (70-90-99%) and air dry it.
The slide is now ready for polymer formation.
To perform this, mix the following:
1 pmol primer
(5′-TGCTGCCGGTCACTTAACAT-3′) (SEQ ID NO:19)
5 nmol each of dATP, dCTP, dGTP and dTTP
5 μg BSA
5 μl 10×Φ-29 buffer (1×Φ-29 buffer: 50 mM Tris.HCl pH 7.5, 10 mM MgCl 2 , 20 mM (NH 4 ) 2 SO 4 , 1 mM DTT)
340 ng Φ-29 DNA polymerase
water to 50 μl
Add the mixture to the slide, spread with a coverslip and incubate at 30° C. for 1 hour.
Transfer the slide to washing buffer (4×SSC, 0.05% Tween®-20) and wash for 5 minutes at ambient temperature.
Dehydrate the slide in an ethanol series (70-90-99%) and air dry it.
The slide is now ready for the cascade reaction.
To perform the cascade reaction, mix the following reagents:
4 pmol of the primer used to generate the polymer
4 pmol of a primer complementary to the polymer (in this case:
5′-AAGATGATATTTTCTTTAATG-3′) (SEQ ID NO: 20)
5 nmol each of dATP, dCTP and dGTP
4 nmol dTTP
1 nmol digoxigenin dUTP
5 μl glycerol
5 μl 10×Φ-29 buffer
340 ng Φ-29 DNA polymerase
water to 50 μl.
Add the mixture to the slide, spread with a coverslip and incubate at 37° C. for 1 hour. Transfer the slide to washing buffer and equilibrate in this buffer for 5 minutes.
Then add 100 μl fluorescein-labeled anti-digoxigenin antibody to visualize the digoxigenin-labeled DNA synthesized in situ (spread with a coverslip). The antibody should be in washing buffer supplemented with 5% non-fat dry milk. Incubate for 30 minutes at ambient temperature to 37° C. and away from light. Wash the slide 3×5 minutes in washing buffer at ambient temperature.
The slide is now ready to be analyzed.
22
1
30
DNA
Artificial Sequence
oligonucleotide primer
1
ttagggttag ggttagggtt agggttaggg 30
2
30
DNA
Artificial Sequence
oligonucleotide primer
2
ccctaaccct aaccctaacc ctaaccctaa 30
3
16
DNA
Artificial Sequence
oligonucleotide primer
3
gaaatttcga aatttc 16
4
24
DNA
Artificial Sequence
oligonucleotide primer
4
gaaatttcga aatttcgaaa tttc 24
5
20
DNA
Artificial Sequence
oligonucleotide
5
gaaagaaaga aagaaagaaa 20
6
20
DNA
Artificial Sequence
oligonucleotide
6
tttctttctt tctttctttc 20
7
28
DNA
Artificial Sequence
oligonucleotide
7
gaaagaaaga aagaaagaaa gaaagaaa 28
8
28
DNA
Artificial Sequence
oligonucleotide
8
tttctttctt tctttctttc tttctttc 28
9
28
DNA
Artificial Sequence
amplified oligonucleotide with amplification
of 12 units of irrel evant sequence between units of sequence
with dyad symmetry
9
gaaatttcnn nnnnnnnnnn gaaatttc 28
10
48
DNA
Artificial Sequence
amplified oligonucleotide with amplification
of 12 units of irrel evant sequence between units of sequence
with dyad symmetry
10
gaaatttcnn nnnnnnnnnn gaaatttcnn nnnnnnnnnn gaaatttc 48
11
32
DNA
Artificial Sequence
oligonucleotide primer
11
gaaatttcga aatttcgaaa tttcgaaatt tc 32
12
56
DNA
Artificial Sequence
oligonucleotide
12
tttcgaaatt tcgaaatttc gaaatttcga aatttcgaaa tttcgaaatt tcgaaa 56
13
19
DNA
Artificial Sequence
T7 promoter
13
ccctatagtg agtcgtatt 19
14
19
DNA
Artificial Sequence
dyad symmetry of T7 promoter
14
aatacgactc actataggg 19
15
38
DNA
Artificial Sequence
oligonucleotide
15
ccctatagtg agtcgtatta atacgactca ctataggg 38
16
10
DNA
Artificial Sequence
oligonucleotide
16
acaaatttgt 10
17
20
DNA
Artificial Sequence
oligonucleotide
17
acaaatttgt acaaatttgt 20
18
92
DNA
Artificial Sequence
Cystic Fibrosis probe
18
aagatgatat tttctttaat gttttttttt tataatgtta agtgaccggc agcaaaatgt 60
tttttttttt tttttcatca taggaaacac ca 92
19
20
DNA
Artificial Sequence
polymer primer
19
tgctgccggt cacttaacat 20
20
21
DNA
Artificial Sequence
primer complementary to the polymer
20
aagatgatat tttctttaat g 21
21
40
DNA
Artificial Sequence
oligonucleotide
21
gaaatttcga aatttcgaaa tttcgaaatt tcgaaatttc 40
22
12
DNA
Artificial Sequence
oligonucleotide
22
nnnnnnnnnn nn 12 | A process for generating multiple linear complements of a single strand, circular nucleic acid template containing at least one cleavage site is described. The process consists of combining the single strand, circular nucleic acid template with polynucleotide primers under conditions sufficient for hybridization; extending the polynucleotide primer more than once around the circle to generate a complementary displacement of more than one continguous complement of the single strand, circular nucleic acid template. Also described is a process of synthesizing novel single strand, circular nucleic acids between 30 an 2200 nucleotides. The process consist of synthesizing a linear polynucleotide; combining the linear polynucleotide with a complementary linking oligonucleotide under conditions sufficient for hybridization; and ligating the linear polynucleotide pto produce a single strand, circular nucleic acid. | 2 |
BACKGROUND OF THE INVENTION
This invention relates generally to construction materials, and more particularly, to a stucco coating composition, and method for preparing same, which is easily applied by any of severl known techniques, and which is durable against environmental effects.
Conventional stucco materials and plastering compositions are difficult to apply, using conventional troweling techniques, so as to achieve a durable surface coating which adheres well to the surface on which it is applied and which produces the desired, aesthetically pleasing surface texture. For this reason, highly skilled artisans required if a stucco surface which has the appearance of being professionally applied is to be produced. Known stucco compositions must have a soft, or somewhat watery, texture if good adhesion to the surface on which it is applied is to be achieved. However, a soft textured composition is not easily applied by conventional troweling techniques because it slides off of the trowel before it can be applied to a horizontal surface, such as a wall, and then does not produce the desired surface texture when dry.
As an alternative to the soft textured compositions mentioned above, the prior art has produced acceptable surface textures by using conventional compositions having a firmer consistency. As intimated hereinabove, such a firm composition does not provide adequate adhesive characteristics, thereby requiring a lathing or wire mesh to be applied to the surface prior to the application of the stucco composition. Clearly, this approach requires substantial preparation and is, therefore, quite costly in terms of materials and labor.
It is a further problem with known stucco compositions that they are adversely affected by the weather and environmental conditions. For example, some stucco compositions tend to fade, soften, or crack after a relatively short period of exposure to ultraviolet radiation, elevated temperature, and high humidity. Such known compositions are also adversely affected by salt spray, and tend to absorb excessive amounts of water when subjected to extended periods of rain.
It is, therefore, an object of this invention to provide an inexpensive stucco composition which is easily applied by any of several known techniques, including troweling, spraying, and rolling.
It is a further object of this invention to provide a stucco composition which adheres well to the surface on which it is applied, notwithstanding that it is applied while it has a sufficiently firm consistency to be easily applicable with a conventional trowel.
It is yet a further object of this invention to provide a stucco composition which does not require extensive preparation of the surface to which it is to be applied, such as by coating with a sealant or by applying lathing or wire mesh.
It is another object of the invention to provide a stucco composition which is resistant to the effects of the weather, including freezing during application.
It is still a further object of this invention to provide a coating material which can withstand direct sunlight, elevated temperature, and high humidity for extended periods.
It is still another object of this invention to provide a coating material which is resistant to salt spray.
SUMMARY OF THE INVENTION
The foregoing and other objects are achieved by this invention which provides a coating composition consisting of a latex sealer, a mineral aggregate, filler compounds, and a paste of baking flour.
In a practical embodiment of the invention, a latex sealer sold under the tradename UCAR (Nos. 505/515) (trademark of Union Carbide) has been used. Sand has been used as the mineral aggregate. In a preferred embodiment, a coarse grade of sand is used. As a filler, calcium carbonate (CaCO 3 ) has been used with good results. The mean particle size of the mineral aggregate is therefore substantially larger than that of the filler. In a specific, particularly advantageous embodiment of the invention, a limited quantity of titanium dioxide (TiO 2 ) has been used to enhance the white color of the present composition.
In accordance with a method aspect of the invention, UCAR latex is prepared as a paste. Baking flour is also prepared as a paste, and mixed with the UCAR Nos. 505/515 brank latex paste. A minor proportion of the mineralized aggregate material, illustratively sand, is added to the mixture of latex and flour, and mixed well. Subsequently, at least one filler compound, illustratively calcium carbonate, is added to the mixture of latex, flour and mineral aggregate. In a particularly advantageous embodiment of the invention, a small amount of titanium dioxide is added to the mixture. The remaining sand is added to the mixture and the mixing is continued until a uniform composite is formed. The consistency and texture of the mixture may be adjusted by the addition of more sand or water. It is preferred that the mixing be performed at a relatively slow speed, such as is conveniently achieved by a portable cement mixer.
DETAILED DESCRIPTION OF THE INVENTION
A five gallon mixture of the composition according to the invention can be prepared in accordance with the following specific illustrative embodiment wherein the ingredient amounts are given in the units in which they are most conveniently measured:
______________________________________Ingredient Amount______________________________________UCAR brand latex (Nos. 505/515) 11/4 gal.Baking flour Paste 7 oz.Sand (course grade) 40 lb.Calcium Carbonate 10 lb.Titanium Dioxide 2 lb.Water up to 3 oz., optionalStone 71/2 lb., optional______________________________________
A latex sealer is the base of the protective coating composition according to this invention. Latex sealers are known in the art and are commercially procurable. A latex sealer, manufactured by Union Carbide under the registered tradename UCAR, has been found to give good results. In a preferred embodiment, UCAR Nos. 505/515 brand latex is used. UCAR Nos. 505/515 brand latex each comprises a mixture of vinyl chloride monomer, vinyl acetate monomer, and butyl acrylate monomer, in varying proportions along with surfactants to reduce foaming and increase drying time. The specific proportions are not critical to the practice of the invention.
Regular baking, or wheat-based flour, is prepared as one would prepare a glue of such flour in a mixture of approximately one part flour to four parts water. In a preferred embodiment, a half cup of flour is made into a paste with two cups of water by the following method. The water is brought to a boil and then allowed to stand at room temperature for a few minutes so that it is warm, but not hot (about 150° F., for example). The flour is stirred into the warm water and the mixture is heated to a boil for about 5 minutes. The boiled mixture is cooled slightly before being added to the latex. In the specific illustrative embodiment shown above, about 7 oz. of the prepared flour paste is combined with about 11/4 gal. UCAR Nos. 505/515 brand latex sealer.
I have found that the addition of the baking flour paste is essential to create a composition having the desired workability. In an experimental composition, the absence of the flour paste resulted in a composition having a firmer consistency which would not stay on the trowel and which would not be susceptible to spraying or rolling onto a surface with ease.
A mineral aggregate, typically sand, forms the bulk of the composition. Quartz stone may be added, if desired, to give a pleasing aesthetic effect to the surface. Sand having particle sizes greater than 1/8 inch is generally considered to be coarse grade, and is preferred if a rough surface finish is desired. However, finer grades of sand would be acceptable and would produce different aesthtic effects which may be desired in certain circumstances. It should be noted, however, that the amount of latex sealer must be increased when finer grain sand is used. It should also be noted that the average particle size of the mineral aggregate affects the surface area coverage of the final product. The larger the average particle size, the less area that can be covered with a given quantity of coating composition. In the specific illustrative embodiment described herein, about 40 pounds of sand and about 71/2 pounds of quartz stone were used. The total weight of a five gallon unit of the coating composition in accordance with the invention is approximately 70 pounds.
The quantity and composition of the filler ingredients and pgiments can be varied as required to produce certain results. In the specific illustrative embodiment herein described, a preferred filler is calcium carbonate because it is relatively inexpensive. Zinc oxide can be used, either alone or in combination with calcium carbonate, to retard drying time and to act as a whitening agent or pigment. A whitening agent is necessary to make the composition opaque. Titanium dioxide is the preferred whitening agent. However, I have discovered that it is important not to add too much titanium dioxide as this results in a final composition which is brittle upon drying and which does not exhibit the desired durability against the effects of the weather.
Commercially procurable pigments can be added, in such quantities as required, to give the composition the desired color. Examples of pigments which have been used sucessfully in the composition are: universal tinting colors available from Benjamin Moore and Color Trend pigments available from Tenneco Chemicals.
The mixture is water soluble, and hence, additional water may be added to adjust the consistency of the product. In certain circumstances, such as when application is to occur in very cold weather, another solvent, such a ethylene glycol, may be substituted for water to prevent freezing. To obtain a thicker consistency, additional sand or stone may be added.
The method for preparing this composition basically entails the following procedure. The flour paste is prepared as described above. Then the flour paste is combined with the latex and slowly mixed in a rotatable mixing chamber. A portable cement mixer has been used with good results. About one quarter of the mineral aggregate is added to the latex-flour paste mixture to aid in mixing the dry ingredients. Then, the filler ingredients and pigments are added, one ingredient at a time, while mixing continues; each being thoroughly commingled with the mixture before the addition of the next. Finally, the remainder of the sand is added with continued mixing. Additional water or solvent may be added to obtain the desired consistency. Quartz stone may be added at this point for aesthetic effect.
The proportions of the stone and solvent are adjustable by the processor or the workmen to obtain the consistency required. The consistency of the product can be tested quite simply on a trowel. It is preferred that the composition have a consistency such that it remains on a trowel for at least eight seconds. This affords a sufficient time to apply the composition to a surface to be coated. It is preferrable that the composition remain on the trowel, however, for about 20 to 30 seconds. A thinner consistency is required for spraying or rolling the composition. The composition according to this invention can be applied over any surface, including metal, without any special preparation such as priming with a sealer, and without requiring lathing or a wire mesh framework. The composition typically dries in 3-4 hours depending on the ambient humidity. As discussed above, drying can be retarded by the addition of zinc oxide.
The subject stucco composition has been subjected to a variety of environmental tests. In the first test, the composition was applied as a coating over a number of ceramic tiles. The coating was applied to the unglazed side of the tile, and was allowed to dry at room temperature for approximately forty-eight hours. At the end of the forty-eight hours, the coating was subjected to a weather test which included ultraviolet radiation, and a temperature of 115 degrees Fahrenheit at 80 percent relative humidity for 1000 hours. After the end of 1000 hours, the coating mixture, which had a light tan color prior to the test, showed no color fading, softening, cracking, spalling (chipping or flaking) or crazing (fine hair line cracks). In addition, the environmental stress applied to the coating did not cause any surface degradation.
In a second test, several of the coated tiles were placed in a salt spray chamber and subjected to salt spray for approximately 700 hours. At the end of the 700 hours, the coatings on the tiles did not change color, soften, crack, spall, or craze. Moreover, no surface degradation was evident.
Several of the tiles were immersed in room temperature water for approximately forty-eight hours. Upon being removed from the water, the tiles were blotted dry and it was found that the coating absorbed approximately four percent of water. The tiles were then dried in a circulating hot air oven for sixteen hours at approximately 180 degrees Fahrenheit. The coating showed no evidence of deterioration following either treatment.
The stucco coating was then subjected to a thermal shock test. First, the coated test tiles were immersed in room temperature water for five hours, then three hours at 10 degrees Fahrenheit and then sixteen hours at 140 degrees Fahrenheit. This cycle was repeated five times. At the end of the five cycles, the stucco coating was examined and there was no indication of any change in color, softening, cracking, spalling, crazing, or any other surface deterioration.
The coating was subjected to a flamability test which entailed holding the coating directly in the flame of a Bunsen Burner. There was no evidence of flamability for the first seven minutes. Thereafter, there was evidence of a very slight degree of flamability. More importantly, however, the stucco composition showed a self-extinguishing flamability characteristic.
Although the invention has been described in terms of specific embodiments and applications, persons skilled in the art, in light of this teaching can generate additional embodiments without departing from the spirit or exceeding the scope of the claimed invention. Accordingly, the descriptions herein are to facilitate comprehension of the invention, and should not be construed to limit the scope thereof. | A composition of the type which is applied to a surface for protecting it against environmental influences and for producing an aesthetic effect. The composition is particularly suited for being applied with a trowel to form a textured surface, such as stucco, or for being sprayed onto a surface. Baking flour is mixed into a paste-like mixture with water and added to a latex sealer paste. Sand, preferrably of a coarse grade, is then added to the mixture. The mixture can then be provided with filler compounds, such as calcium carbonate, and a pigment, such as titanium dioxide. The mixture has been shown to be effective against a variety of adverse environmental influences, including ultraviolet radiation, humidity, salt spray, fire, and thermal effects. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
Priority is claimed of U.S. provisional application 60/171,619 filed in the U.S. Patent & Trademark Office on Dec. 23, 1999, the complete disclosure of which is incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided by the terms of F04611-97-C-0053 to the Air Force Rocket Laboratory.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is directed to a process for making elastomer-based insulation for rocket motors and, in particular, to a process in which fragile carbon fibers are mixed with and preferably homogeneously dispersed in ethylene propylene diene monomer (EPDM) without requiring the use of a volatile solvent for dissolution of EPDM during fiber incorporation. The insulation of this invention is especially useful for placement in the nozzle or case, including between a solid propellant grain and a rocket motor case for protecting the case from high temperatures experienced during burning of solid propellant grains.
2. State of the Art
Solid rocket motors typically include an outer case or shell housing a solid propellant grain. The rocket motor case is conventionally manufactured from a rigid, yet durable, material such as steel or filament-wound composite. The propellant is housed within the case and is formulated from a composition designed to undergo combustion and thereby produce the requisite thrust for attaining rocket motor propulsion.
During operation, a heat insulating layer (insulation) protects the rocket motor case from heat and particle streams generated by the combusting propellant. Typically, the insulation is bonded to the inner surface of the case and is generally fabricated from a composition capable of withstanding the high temperature gases produced when the propellant grain bums. A liner layer (liner) functions to bond the propellant grain to the insulating layer and to any noninsulated portions of the case, as well as to inhibit interfacial burning. Liner compositions are generally known to those skilled in the art. An exemplary liner composition and process of applying the same to a case is disclosed in U.S. Pat. No. 5,767,221, the complete disclosure of which is incorporated herein by reference to the extent that it is compatible with this specification.
The combustion of solid rocket propellant generates extreme conditions within the case of the rocket motor. For example, temperatures inside the rocket motor case typically reach 2,760° C. (5,000° F.), and interior pressures may exceed 1,500 psi. These factors combine to create a high degree of turbulence within the rocket motor case. In addition, particles are typically entrained in the gases produced during propellant combustion. Under the turbulent environment, these entrained particles can erode the rocket motor insulation. If the insulating layer and liner are pierced during rocket motor operation, the casing is susceptible to melting or degradation, which can result in failure of the rocket motor. Thus, it is crucial that insulation compositions withstand the extreme conditions experienced during propellant combustion and protect the case from the burning propellant. It is also crucial that insulation compositions possess acceptable shelf life characteristics such that they remain sufficiently pliable, without becoming fully cured, until used in application to the rocket motor casing. This requirement is essential because the production of a given lot of insulation may have to wait in storage for a number of months prior to use. Typically, the insulation may be stored in large rolls in an uncured, or at most a partially cured, state until ready for use. A number of curing agents are well known and are conventionally employed but still must be compatible with the overall EPDM formulation to permit satisfactory shelf life. This in turn requires a balancing of curing agent activity.
In the past, attempts at producing insulating materials that would protect the rocket motor case focused on filled and unfilled rubbers and plastics, such as phenolic resins, epoxy resins, high temperature melamine-formaldehyde coatings, ceramics, polyester resins; and the like. These plastics, however, crack and/or blister as a result of the rapid temperature and pressure fluctuations experienced during combustion.
Elastomeric compositions have also been used as rocket motor insulation materials in a large number of rocket motors. The elastomeric compositions have been selected because their mechanical, thermal, and ablative properties are particularly suited for rocket motor applications. However, the ablative properties of elastomers are often inadequate for rocket motor operation. For example, insulation, whether thermosetting or thermoplastic, is characterized by relatively high erosion rates unless reinforced with a suitable filler. The criticality of avoiding such high erosion rates is demonstrated by the severity and magnitude of the risk of failure due to erosion. Most insulation is, of necessity, “man-rated” in the sense that a catastrophic failure can result in the loss of human life—whether the rocket motor is used as a booster for launch of a space shuttle or is carried tactically underneath the wing of an attack aircraft. The monetary cost of failure in satellite launches is well-publicized and can run into the hundreds of millions of dollars.
In order to improve the ablative properties of elastomeric compositions, it has been proposed to reinforce the elastomeric compositions with fillers, such as organic-based fibers or carbon fibers. For instance, an exemplary carbon fiber-filled rocket motor insulation composed of solid NORDEL® 1040 as the primary terpolymer is commonly known in the industry as the STW4-2868 thermal insulation and has the following composition:
TABLE A
STW4-2868 THERMAL INSULATION FORMULATION
(carbon fiber; parts by weight)
Parts
Ingredient
Function
by Weight
NORDEL ® 1040
Primary EPDM terpolymer base
80
Neoprene FB
Secondary polymer base
20
Zinc oxide
Activator
5
Sulfur
Curative
1
HAF carbon black
Pigment
1
MBT
Accelerator
1
AGERITE ® Resin D
Antioxidant
2
AGERITE ® HPS
Antioxidant
1
Tellurac
Accelerator
0.50
Sulfads
Accelerator
0.75
VCM carbon fibers
Filler
41
Total Parts by Weight
153.25
Although organic-based fibers can be dispersed within the EPDM without too much difficulty, the homogeneous dispersion of carbon fibers in an elastomeric composition presents a difficult processing problem. The mixing process is complicated by the fragility of the carbon fibers. Mixing of carbon fibers into a solid elastomer under high shear physically deteriorates the carbon fibers into smaller particles or shreds, thereby negating the advantageous physical attributes that the carbon fibers would otherwise have contributed to the insulation.
Conventionally, the problem of carbon fiber fragility has been addressed by dissolving the elastomer into a solution with an appropriate organic solvent to lower the viscosity of the elastomer or elastomer mixture. Suitable solvents include, by way of example, hydrocarbons such as hexanes, heptanes, and/or cyclohexane. The frangible graphitized carbon fibers can then be mixed with the solution in, for example, a sigma-blade mixer without significant breakage of or damage to the carbon fibers. The material is then sheeted out and the solvent is allowed to evaporate at ambient atmosphere or in an oven.
The use of solvent in this processing technique presents several drawbacks. For example, solvent processing techniques, such as those conventionally used-to disperse carbon fibers in EPDM rubber, are relatively expensive. Material costs are increased by the use of solvents, as are processing costs, since additional workers and equipment are required to handle and process the solvents. Further, considerable costs and worker safety issues are associated with the disposal of hazardous volatile organic solvents.
Thus, although it has been long recognized that carbon fiber-filled EPDM is an excellent candidate for rocket motor insulation, a low cost and nonhazardous solvent-free synthesis route that produces EPDM insulation having carbon fibers homogeneously dispersed therein, but without being subject to significant breakage or damage would be desirable.
SUMMARY OF THE INVENTION
Therefore, a method of manufacturing ethylene propylene diene monomer (EPDM) rocket motor insulation in which carbon fibers are dispersed and immobilized in the EPDM polymeric matrix, but are not excessively fractured or fragmentized, i.e., broken into smaller fragments, when encountering degrees of shear necessary to homogeneously or otherwise distribute or disperse the carbon fibers in the EPDM polymeric matrix is provided.
The method of the present invention is a substantially solvent-free method in which the insulation is manufactured via distributive/reduced shear mixing to distribute the fragile carbon fibers into a rubber matrix without excessive damage.
In accordance with one embodiment of this substantially solvent-free method, the elastomer composition comprises carbon fibers and EPDM terpolymer, at least 50 wt % of which is introduced as an ingredient into the mixing apparatus as liquid EPDM terpolymer having a sufficiently low molecular weight and high diene content to permit dispersion of the carbon fibers in the EPDM without substantial fragmentation of the fibers. As referred to herein, “liquid EPDM” means EPDM terpolymer that is flowable at room temperature. Suitable mixing apparatuses for this embodiment include sigma-blade and vertical-blade mixers. Certain kneaders, such as discussed below in connection with another embodiment of the inventive method, capable of superimposing a rotational and axial mixing motion to the carbon fibers can also be used.
In accordance with another embodiment of the invention, the elastomer composition is prepared, optionally under substantially solvent free conditions with little or no liquid EPDM terpolymer, by use of a kneader capable of rotating a screw having a discontinuous screw thread about the screw axis while superimposing an axially reciprocating stroke to the screw. This kneader imparts low shear distributive mixing of the carbon fibers in the EPDM terpolymer. The kneader used in this embodiment is especially suitable where little or no liquid EPDM ingredient and no volatile solvent are included in the formulation.
As referred to herein, carbon fibers are fibers having been subject to at least substantial graphitization or carbonization, and preferably have about 98 wt % or more carbon content.
Other aspects and advantages of the invention will be more apparent to those skilled in the art upon reading the detailed description and appended claims which, when read in conjunction with the accompanying drawings, explain the principles of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings serve to elucidate the principles of this invention. In such drawings:
FIG. 1A is a schematic cross-sectional view of a rocket motor assembly in which the insulation is provided;
FIG. 1B is an enlarged schematic cross-sectional view of the area encircled and labeled “SEE FIG. 1 B” in FIG. 1A ;
FIG. 2 is a schematic cross-sectional view of a kneading apparatus suited for use with this invention;
FIG. 3 is a cross-sectional view taken along sectional line III—III in FIG. 2 ;
FIG. 4 is a schematic view of an axial segment of a discontinuous screw barrel of the kneading apparatus of FIG. 2 , with the axial segment section being projected onto a flat plane for explanatory purposes;
FIG. 5 is the schematic view of FIG. 4 , with kneading pins of the kneading apparatus being superimposed onto the illustrated axial segment;
FIG. 6 is the schematic view of FIG. 5 , showing the paths of relative movement of selected ones of the kneading pins relative to the discontinuous screw barrel and, in particular, relative to the screw flights of the barrel; and
FIG. 7 is a schematic, cross-sectional view of a char motor used in testing examples discussed hereinbelow.
DETAILED DESCRIPTION OF THE INVENTION
The present insulation compositions 10 , when in a cured state, are especially suited for disposal on the interior surface of the rocket motor case 12 , as shown in FIGS. 1A and 1B . Typically, a liner 14 is interposed between the insulation composition 10 and propellant 16 . The insulation composition 10 and the liner 14 serve to protect the case 12 from the extreme conditions produced by the propellant 16 as it undergoes combustion reactions and is exhausted through nozzle assembly 18 . Methods for loading a rocket motor case 12 with the insulation composition 10 , the liner 14 , and the propellant 16 are known to those skilled in the art, and can be readily adapted within the skill of the art without undue experimentation to incorporate the insulation composition 10 of this invention.
Unlike conventional techniques that make use of a solvent within a mixing apparatus to achieve adequate distribution of carbon fibers in solid EPDM ingredients without significant fiber fragmentation, the method of this invention achieves distribution of carbon fibers in an EPDM matrix under solvent-free conditions, or at least substantially solvent-free conditions. As referred to herein, “substantially solvent-free” means that the process is performed with a sufficiently small amount of volatile solvent that, even if the volatile solvent is not removed during manufacture of the insulation, the volatile solvent will not be present in a sufficient amount to violate applicable environmental or safety regulations during manufacture, rocket motor storage, or rocket motor operation due to volatilizing of the solvent. Generally, the term “substantially solvent-free” preferably means not more than about 5 wt % of volatile solvent based on the dry ingredients of the insulation. Preferably, the process is conducted completely free of volatile solvent.
In accordance with a first embodiment of this invention, this and other objects are achieved by using liquid EPDM as a significant portion of the EPDM ingredients introduced into the mixing apparatus. The amount of liquid EPDM ingredient used to ensure adequate distribution of the fibers, without accompanying excessive fragmentation of the fibers, depends upon the mixing apparatus used. Generally, where a conventional mixer known in the insulation industry, such as a sigma-blade mixer, is used to disperse the carbon fibers within the EPDM matrix, the insulation composition preferably contains at least about 50% by weight, and more preferably at least about 90% by weight, liquid EPDM as an ingredient, based on the total weight of the EPDM (i.e., both the solid and liquid EPDM ingredients). Where a vertical blade mixer is used to disperse the carbon fibers within the EPDM matrix, the insulation composition preferably contains slightly more liquid EPDM, such as at least about 90% by weight, and more preferably at least about 95% by weight liquid EPDM as an ingredient, based on the total weight of the EPDM (i.e., both the solid and liquid EPDM ingredients). Where a kneader such as the one illustrated in FIGS. 2-6 is used, even less of the liquid EPDM (or even no liquid EPDM, as detailed in the second embodiment below) is required to obtain homogeneous dispersion of the fibers without excessive fragmentation, i.e., all of the EPDM can be in a solid state when introduced into the kneader.
Generally, the EPDM, i.e., both the solid and liquid ingredients, comprises from about 35 wt % to about 90 wt %, and still more preferably from about 45 wt % to about 75 wt %, of the total weight of the rocket motor insulation. The EPDM terpolymer can be formed from 1,4-hexadiene, dicyclopentadiene, and/or an alkylidene norbornene, such as ethylidene norbornene (ENB), as the diene component. Suitable commercially available liquid EPDM terpolymers are TRILENE® 67A and TRILENE® 77, available through Uniroyal Chemical Company of Middlebury, Conn. It is noted, however, that a portion or all of the liquid EPDM can be substituted for another liquid polymer ingredient, such as liquid polyurethanes, so long as the substituted liquid polymer ingredient obtains the same distributive function with regard to the carbon fibers without excessive fragmentation. Suitable solid EPDM terpolymers having a 1,4-hexadiene component for use in this invention include NORDEL® 1040, NORDEL® 2522, and NORDEL® 2722E, made by DuPont Dow Elastomers of Wilmington, Del. Suitable solid EPDM terpolymers having an ENB diene component for use in this invention include, without limitation, and as stated above, KELTAN® 4506, KELTAN® 1446A, KELTAN® 2308, each of which is available from DSM Elastomers of the Netherlands, and NORDEL® IP 4520 and NORDEL® IP 4640, both of which are and continue to be available from DuPont Dow Elastomers.
The curing package can include sulfur curing agents and/or peroxide curing agents for cross-linking and/or chain extending polymers or polymer precursors (e.g., prepolymers). Suitable insoluble sulfur curing agents are AKROSPERSE® IS-70 from Akrochem Corporation of Akron, Ohio, and CRYSTEX® OT-20 available through Charles H. Haynes, Inc. Other forms of elemental sulfur can also be used. Suitable peroxide curing agents include dicumyl peroxide, 2,5-dimethyl-2,5-bis-(t-butylperoxy)hexane, 2,5-dimethyl-2,5-bis-(benzoylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexane, n-butyl-4,4-bis-(t-butylperoxyl)valerate, 4,4′-methyl-bis-(cyclohexylamine)carbomate, 1,1-bis-(t-butylperoxy)-3,3,5-trimethylcyclohexane, α,α′-bis-(t-butylperoxy)-diisopropylbenzene, 2,5-dimethyl-2,5-bis-(t-butylperoxy)hexyne-3, and t-butyl perbenzoate. A commercially available peroxide is available under the trade name DI-CUP® 40KE, which comprises about 40% dicumyl peroxide on a clay carrier (the clay carrier is available from Burgess Pigment Company of Sandersville, Ga). Another suitable curing agent (besides sulfur and peroxide curing agents) is bromomethyl alkylated phenolic resin, available as SP-1056 from Schenectady Int'l, Inc. of Schenectady, N.Y.
In typical formulations, the curing agent comprises from about 0.5 phr to about 8 phr and, more preferably, about 2 phr to about 5 phr. As referred to herein and generally accepted in the art, “phr” means parts by weight per one hundred parts-by weight polymer.
The curing package preferably also includes at least one phosphate cure accelerator. In the case of a sulfur curing agent, the accelerator can be, by way of example, RHENOCURE® AP-5, RHENOCURE® AP-7, RHENOCURE® AP-3, RHENOCURE® ZADT/G, and RHENOCURE® S/G, which are available from Rhein Chemie Corporation of Trenton, N.J., and Accelerator VS, available from Akrochem Corporation. Additional cure accelerators that may be used in combination with the phosphate cure accelerator include butyl zimate; benzothiazyl disulfide (commercially known as ALTAX®); dithiocarbamate-containing blends (such as AKROFORM® DELTA P.M. from Akrochem Corporation); and sulfides such as dipentamethylenethiuram hexasulfide (such as SULFAD® from R.T. Vanderbilt Company, Inc. of Norwalk, Conn.). While the use of Accelerator VS was initially unacceptable in some formulations because of the foul odor problem it generated, it has also been now found that such formulations can be prepared with no-significant odor if about 1.0 phr magnesium oxide is added thereto.
Suitable cure activators for the curing package include metal oxides, such as zinc oxide (e.g., TZFD-88p from Rhein Chemie Corp.), magnesium oxide (e.g., ELASTOMAG® 170 from Morton Chemical Co.), and stearic acid (including palmitic acid), which is available from Harwick Standard Distribution Corp. of Akron, Ohio.
The carbon fibers are fibers which have been subjected to at least partial graphitization or carbonization and preferably have about 98 wt % or more carbon content. The carbon fibers should have lengths suitable for distribution in mixing equipment. Generally, the carbon fibers are preferably noncontinuous and not less than about {fraction (1/16)}of an inch in length and not more than about 6 inches in length, although these ranges are not exhaustive as to the scope of the invention. Carbon fibers are supplied commercially by several companies, including FORTAFIL® fibers (e.g., FORTAFIL® 140 and FORTAFIL® 144) from Akzo Nobel of Knoxville, Tenn., carbon fibers available from Amoco of Charleston, S.C., and PANEX® 33 (¼″×8″ or ¼″×15″), supplied by Zoltek Corporation of St. Louis, Mo. Generally, the carbon fibers are present in an amount of from about 2 wt % to about 50 wt %, more preferably from about 10 wt % to about 30 wt %, based on the total weight of the insulation. The amount of carbon fibers will generally vary depending on the presence of other ingredients, such as char-forming agents, especially phosphate fire retardants, which supplement the carbon fibers by imparting desired physical properties to the insulation.
The carbon fibers can be used alone or in combination with other materials affecting the ablative and mechanical properties of the insulation. By way of example, suitable materials include polybenzoxazole fibers, polybenzimidazole fibers, aramid fibers, iron oxide, milled glass, silica, ceramic clay, and the like. Suitable silica particles include HISIL® 233 available from PPG Industries, Inc. of Lake Charles, La., and hydrophobized silica particles available from Cabot Corporation of Boston, Mass., as CAB-O-SIL® TS-610, CAB-O-SIL® TG-308F, CAB-O-SW® TG-720, CAB-O-SWL® TS-500, CAB-O-SIL ® TS-530, and CAB-O-SWL® TG-810G; Degussa AG of Germany as AEROSIL® R972, AEROSIL® R974, AEROSIL® R812, AEROSIL® R812S, AEROSIL® R711, AEROSIL® R504, AEROSIL® R8200, AEROSIL® R805, AEROSIL® R816, AEROSIL® R711, and AEROSIL® R104; and Tulco Inc. of Ayer, Mass., as TULLANOX® 500.
Suitable additives that may be added as required or desired include one or more of the following, in various combinations: antioxidants, flame retardants, tackifiers, plasticizers, processing aids, carbon black, pigments, and bonding agents.
Representative antioxidants for improving the longevity of the cured elastomer include, by way of example, diphenylamine reacted with acetone, available as BLE®-25 Liquid from Uniroyal Chemical Company; a mixture of mono-, di-, and tri-styrenated phenols, available as AGERITE(® SPAR from B.F. Goodrich Chemical Ltd. of Australia. Other suitable antioxidants include polymerized 1,2-dihydro-2,2,4-trimethylquinoline (AGERITE® RESIN D) and mixed octylated diphenylamines (AGERITE® STATLITES), each of which is available from R.T. Vanderbilt Co., Inc.
Fillers that function as flame retardants, or char-forming additives, can be used, if desired, in lesser amounts than most other additives, which makes it easier to formulate the insulation with good mechanical properties. Both inorganic and organic flame retardants ate expected to be useful in the present invention. Examples of organic flame retardants include: chlorinated hydrocarbon, available as DECHLORANE®, in combination with antimony oxide (optionally with diisodecyl phthalate (DIDP)) or hydrated alumina (such as Hydral 710 aluminum trihydrate); melamine cyanurate; phosphate and phosphate derivatives, available as PHOS-CHEK® P30 (ammonium polyphosphate) produced by Monsanto Chemical Company of St. Louis, Mo., which can be used alone or in combination with pentaerythritol; DECHLORANE PLUS® 25 from Occidental Chemical Corporation of Niagara Falls, N.Y.; and silicone resin, such as DC4-7051 available through Dow Corning. An example of an inorganic flame retardant is zinc-borate, such as FIREBRAKE® ZB from U.S. Borax Inc. of Valencia, Calif.
Examples of suitable tackifiers are WINGTACK® 95 and AKROCHEM® P-133. Other ingredients, such as pigments and extruder processing aids (e.g., ARMEEN® 18-D) well known in the art and/or suitable for use in rocket motor thermal insulation applications and extruder techniques, are intended to be included within the scope of the present invention. A suitable modifying elastomer is chlorosulfonated polyethylene, such as HYPALON®-20 available from DuPont Dow Elastomers. Nonvolatile plasticizers, such as hydrocarbon oil, can also be used.
The casting of the inventive insulation into a case and curing of the inventive insulation may be performed in accordance with techniques known in the art. As referred to herein and in the appended claims, the inventive composition can be, inter alia, either applied by casting into a rocket motor case and then cured, or cured, optionally cut into appropriate geometry and size, and then applied into the rocket motor case.
Referring now more particularly to FIGS. 2-6 , the kneader in accordance with a preferred embodiment of this invention is a Buss® Kneader available through Buss Compounding Systems, AG, a plant engineering group of Georg Fischer Plant Engineering. A representative Buss® Kneader brand kneader is model MDK/E-46. This kneader is commercially available and is currently believed to have been used in the past in various other industries, including the following: construction; electrical and electronic component parts; automotive parts; chemicals; house appliances; foodstuffs, packaging, and consumer goods. Another similar kneader is available from B&P Process Equipment & Systems.
The Buss® Kneader brand kneader has a housing module (or barrel) 20 defining a chamber 22 . A plurality of additional modules (not shown) having respective chambers can be united together to provide an extended chamber. The housing module 20 can be equipped with a jacket or internal fluid passages for heating. In order to allow for ease in maintenance and operation, the housing module 20 can be a split-barrel arrangement to allow opening of the barrel 20 along its length, thereby facilitating access to the chamber 22 .
In the illustrated embodiment, a single rotatable screw 24 is received in the chamber 22 . Generally, the screw 24 is from about 30 mm to about 200 mm in diameter and has a length-to-diameter (L:D) ratio of from about 8:1 to about 20:1, although this invention is not so limited, given the flexibility of uniting a desired number of modules 20 .
As shown in FIGS. 2-6 , the periphery of the screw 24 has a plurality of screw flights 30 . The screw flights 30 each have a rhombic configuration in the illustrated embodiment, although the present invention is not thereby limited in scope. As best shown in FIG. 4 , the screw flights 30 are arranged relative to each other to provide a plurality of screw flight columns 32 . For each of these screw flight columns 32 , the respective screw flights 30 thereof are aligned along the longitudinal axis of the screw 24 , yet spaced from each other by an axial distance. In a preferred embodiment, the screw 24 has three screw flight columns 32 a , 32 b , and 32 c . The circumferential centers C of the screw flights 30 of screw flight column 32 a are positioned about the circumference at intervals of 120° from the circumferential centers of the screw flights 30 of screw flight columns 32 b and 32 c . Defined between each of the adjacent columns 32 a , 32 b , and 32 c are gaps 34 a , 34 b , and 34 c . Whereas the screw of a conventional single-screw extruder has a continuous spiral or helical screw face extending along its length, the screw 24 of the illustrated embodiment has a discontinuous screw face, with the spiral or helical path of the screw face being interpreted by the gaps 34 a-c (collectively referred to as “gaps 34 ”).
The housing module 20 has kneading pins (also referred to as kneading teeth) 40 , which in the illustrated embodiment have diamond-shaped cross sections. Each of the kneading pins 40 extends from an inner periphery thereof along a respective radial direction of the housing module 20 . As shown in FIG. 5 , the kneading pins 40 collectively define three kneading pin columns 42 a , 42 b , and 42 c , each spaced 120 ° from each other about the circumference of the screw 24 and dimensioned so as to be receivable in the gaps 34 . The kneading teeth 40 can be hollow and connected to a supply means for permitting the injection of fluid constituents through the kneading teeth and directly into the melt.
During operation, the screw 24 is rotated about its longitudinal axis while an axial stroke is superimposed on the screw 24 to oscillate the screw 24 back and forth in the axial direction. A gear box (not shown), also available with the Buss® Kneader brand kneader through Georg Fischer Plant Engineering, preferably ensures that each revolution of the screw 24 is accompanied by one full forward and backwards stroke of the screw 24 . At the same time, the housing module 20 and kneading pins 40 remain stationary relative to the rotating/oscillating screw 24 .
The rotating/oscillating movement of the screw 24 causes the kneading pins 40 to traverse across the faces of respective screw flights 30 , thus generating a shear which cleans the faces of the screw flights 30 and effects dispersion and distributive mixing. This relative movement between the screw flights 30 and the kneading pins 40 is explained below in more detail with reference to FIG. 6 , which shows selected pins 40 a and 40 c and their respective paths of movement relative to the screw 24 . As shown in FIG. 6 , the kneading pins 40 move across the faces of the screw flights 30 and across the gaps 34 , thereby cleaning the faces of the screw flights 30 and causing dispersion and distributive mixing to take place.
As mentioned above, a Buss® Kneader model MDK/E46 having a 46 mm single screw with a process ID ratio of 11:1 can be used. This model of kneader can be used in combination with a Reliance 40 HP 1750 rpm DC Motor and Flex Pak 3000 controller.
Vertical feeds can be provided at different axial locations along the length of the housing module 20 . Preferably, the inlet feeders are jacketed vertical screw feeders. Generally, the polymeric ingredients and carbon fiber are introduced into the most upstream feed, fire retardants and other additives are added further downstream (along the axial direction of the housing module 20 ), and the curing package is introduced at the most downstream feed port. In this manner, the insulation composition may be continuously produced. The temperature of the chamber is generally set in the range of from about 66° C. (150° F.) to 93° C. (200° F.) during operation.
An advantage of using the kneader of this second embodiment is that the insulation composition discharged from the kneader can be introduced directly into an extruder for extrusion of the EPDM material. A suitable extruder for use with the kneader of this second embodiment is a discharge extruder GS70. The ability to extrude in this embodiment provides improvements over conventional techniques, in which the insulation composition is calendered into sheets, then cut.
EXAMPLES
The following examples illustrate embodiments which have been made in accordance with the present invention. Also set forth are examples prepared for comparison purposes. The inventive embodiments are not exhaustive or exclusive, but merely representative of the many types of embodiments which may be prepared according to this invention.
TABLE I
(all units in parts by weight)
COMPARATIVE
EXAMPLE
EXAMPLE
Ingredient
1
2
3
4
5
6
A
B
TRILENE ® 67 [liquid
100
100
100
100
100
100
40
EPDM]
DSM KELTAN ® [solid
50
EPDM]
NORDEL ® 1040 [solid
80
EPDM]
Neoprene FB
20
[plasticizer]
HYPALON ® 20
10
[polymer]
PANEX ® 33 × 8 [¼″
26
fibers]
FORTAFIL ® 144
38.5
45
40.5
30
25.7
26.85
[carbon fibers]
VCM [carbon fibers]
41
AKROCHEM ® P-133
5
[plasticizer/tackifier]
AGERITE ® Stalite S
2
2
2
2
2
2
2
1
[antioxidant]
AGERITE ® Resin D
2
[antioxidant]
HISIL ® 233 [fire
5
5
5
5
5
5
3
retardant filler/char-
forming agent]
FIREBRAKE ® ZB [fire
19.5
retardant
filler/char-forming
agent]
Hydral 710 Aluminum
19.5
Trihydrate [filler]
Carbon black [filler]
1
DC4-7051 [fire
5
8.5
5
5
5
retardant/char-forming
agent]
Ferric oxide
1.13
[filler/pigment]
Antimony oxide (4%
18
DIDP) [fire
retardant/filler]
Dechlorane Plus ® 25
45
[fire retardant
filler/char-forming
agent]
Pentaerythritol PE 200
8.5
[fire retardant
filler/char-forming
agent]
PHOS-CHECK ® P/40
30
[fire retardant
filler/char-forming
agent]
Melamine cyanurate [fire
25
25
25
retardant
filler/char-forming
agent]
Zinc oxide [activator]
5
5
Kadox 920C zinc oxide
5
4
4
4
4
5
[activator]
ALTAX ® [accelerator]
1.1
1.5
1.5
1.5
1.5
1.2
Accelerator VS
2.7
AKROFORM ® Delta
0.3
0.3
0.3
0.3
0.25
P.M. [accelerator]
Sulfads [accelerator]
0.82
0.82
0.82
0.82
0.82
0.75
Butyl zimate
0.5
[accelerator]
RHENOCURE ® AP-5
3.5
[accelerator]
CRYSTEX ® OT-20
1.05
1.22
1.22
1.22
1.22
1.22
[curative]
SP-1056 [curative]
1.1
Captax [accelerator]
1
Tellurac [accelerator]
0.5
Sulfur [curative]
1
Total Parts by Weight
172.8
192.3
223.9
202.3
149.8
171.2
178.95
153.25
Examples 1 and 6
All solid ingredients, with the exception of the TRILENE® 67, were blended in a V-shell blender at ambient temperature over several hours. The TRILENE® 67 was separately introduced into a Brabender mixer equipped with a sigma blade operating at 10 rpm and set to 60° C. (140° F.). The TRILENE® 67 was mixed in the Brabender mixer for a sufficient amount of time to warm the TRILENE® 67 to 60° C. Next, the blended material from the V-shell blender was introduced into the Brabender mixer and allowed to mix with the TRIUENE® 67 until the fibers were uniformly dispersed in the TRILENE® 67. The formulation was then dumped from the Brabender mixer to a mill for shaping into sheets before cooling. Each sheet was about 1.27 cm (0.5 inch) in thickness.
Examples 2 through 5
All solid ingredients, with the exception of the TRILENE® 67 and the carbon fibers, were blended in a V-shell blender at ambient temperature over several hours. The TRILENE® 67 was separately introduced into a Brabender mixer equipped with a sigma blade operating at 50 rpm and set to 77° C.(170° F.). The TRILENE(® 67 was mixed in the Brabender mixer for a sufficient amount of time to warm the TRILENE® 67 to 77° C. Next, the blended material from the V-shell blender was introduced into the Brabender mixer and allowed to mix with the TRILENE® 67. The speed of the Brabender mixer was then slowed to 20 rpm, and the fibers were introduced into the Brabender mixer and mixed until the fibers were uniformly dispersed in the TRILENE® 67. The formulation was then dumped from the Brabender mixer to a mill for shaping into sheets before cooling. Each sheet was about 1.27 cm (0.5 inch) in thickness.
Comparative Examples A and B
Comparative Example A was prepared by mixing all of the ingredients, with the exception of the carbon fiber, in a laboratory mixer. The carbon fiber was incorporated into this mixture in a twin screw extruder (containing counter-rotating screws) by adding the mixed polymeric material and the carbon fibers in a single port of the twin screw extruder. Comparative Example B was made by solvent processing with a hydrocarbon solvent.
TABLE II
Comparative
EXAMPLE
Example
1
2
3
4
5
6
A
B
Average
3.29
3.98
4.89
3.96
4.05
3.31
3.37
3.45
Ablation Rate
for Lower
Section (mm/s)
Average
12.34
9.36
12.63
9.97
12.97
11.80
16.96
12.76
Ablation Rate
for Middle
Section (mm/s)
Average
23.44
14.12
12.72
12.79
20.45
17.94
35.23
18.13
Ablation Rate
for Upper
Section (mm/s)
From Table II, it is seen that the inventive examples containing liquid EPDM as their exclusive EPDM ingredient (i.e., no solid EPDM) exhibited comparative and, in some instances, improved ablative properties to Comparative Example A (containing less than half liquid EPDM based on the total weight of EPDM ingredients) and Comparative Example B (containing no liquid EPDM).
Examples 7 to 9 were prepared in accordance with a second embodiment of this invention by kneading the insulation in a Buss® Kneader. The ingredients of the insulation compositions of Examples 7-9 are set forth below in Table III. The ablative properties of Examples 7-9, a comparison of these properties to that of inventive Example 4, are set forth below in Table IV.
TABLE III
(all units in parts by weight)
EXAMPLE
Ingredient
7
8
9
DSM KELTAN ® 1446A [solid
100
100
100
EPDM]
FORTAFIL ® 243 [carbon fibers]
40.52
44.45
55.55
Cure/Filler
14.86
14.88
14.88
Fire Retardant
47.02
62.72
51.62
Total Parts by Weight
202.40
222.05
222.05
TABLE IV
EXAMPLE
7
8
9
4
Average Ablation Rate for Lower
3.68
2.85
3.44
3.35
Section (mm/s)
Average Ablation Rate for Middle
9.41
8.97
9.79
9.40
Section (mm/s)
Average Ablation Rate for Upper
15.42
14.75
13.61
11.64
Section (mm/s)
As shown by Table IV, the insulation prepared in a Buss® Kneader without any liquid EPDM exhibited comparable erosion resistance to Example 4, which was prepared in a sigma mixer with liquid EPDM.
The tests were performed in a char motor, such as the one illustrated in FIG. 7 . Char motors are constructed to evaluate the ablative properties of solid rocket motor case insulation materials. A char motor includes a propellant beaker 70 to provide the combustion gases, evaluation chambers to hold the test materials, and a constricting nozzle to produce the required pressure. The evaluation chamber is divided into three sections. The first one is a “low-velocity” cylindrical region 72 about eight inches long and eight inches in diameter (approximately the same diameter as the propellant beaker 70 ). A short conical transition chamber 74 constricts the gas flow into a diameter of about 2 inches and vents the propellant gases into a 22-inch long conical test chamber. This test chamber is divided into the “mid-velocity” region 76 and “high-velocity” region 78 .
Samples of insulation material to be evaluated are molded, cured, and bonded with epoxy into each of the test chambers. Prior to assembly, the cured length is determined and the thickness of each evaluation material is measured at selected intervals, nominally one inch apart. Each sample is also weighed. The samples are then assembled into the low-velocity section, the mid-velocity section, and the high-velocity section. After firing, the motor is disassembled and each sample is measured again. The ablation rate is determined by subtracting the post-fired thickness of the insulation (i.e., after the char had been removed) at a given point from the prefired thickness and dividing the result by the bum time of the motor. For these tests, more than one section of material was measured, and the average of all of the sections is reported above.
The char motors were fired with RSRM TP-H1148 (polybutadieneacrylic acid acrylonitrile (PBAN-based)) propellant. For Examples 1-3 and comparative Example A set forth in Tables I and II, the motor was fired for 12.10 seconds at an average pressure of 880 psi. For Examples 4-6 set forth in Tables I and II, the motor was fired for 11.56 seconds at an average pressure of 825 psi. Comparative Example B was fired for 11.89 seconds at an average pressure of 885 psi. For Examples 7-9 and 4 set forth in Tables III and IV, the motor was fired for 12.46 seconds at an average pressure of 916.07 psi.
The foregoing detailed description of the invention has been provided for the purpose of explaining the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated. This description is not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Modifications and equivalents will be apparent to practitioners skilled in this art and are encompassed within the spirit and scope of the appended claims. | This method permits manufacturing EPDM rocket motor insulation in which carbon fibers are dispersed and immobilized in the EPDM polymeric matrix but are not excessively fractured or fragmentized, i.e., broken into smaller fragments, when encountering degrees of shear necessary to homogeneously or otherwise distribute or disperse the carbon fibers in the EPDM polymeric matrix. The method is substantially solvent free and is performed via distributive/reduced shear mixing to distribute the fragile carbon fibers into a rubber matrix without excessive damage. According to one embodiment, at least about 50% of the elastomer composition introduced into the mixing apparatus is liquid EPDM terpolymer having sufficiently low molecular weight and high diene content to permit dispersion of the carbon fibers in the EPDM without substantial fragmentation of the fibers. According to another embodiment, mixing takes place in a kneader capable of rotating a screw having a discontinuous screw thread about the screw axis while superimposing an axially reciprocating stroke to the screw. The kneader imparts low shear distributive mixing of the carbon fibers in the EPDM terpolymer. | 5 |
This application is a continuation of application Ser. No. 08/703,320 filed on Aug. 26, 1996 now abandoned.
FIELD OF THE INVENTION
This invention relates in general to refiners which prepare paper pulp fibers prior to their being delivered to a papermaking machine, and in particular to high density disc refiners.
BACKGROUND OF THE INVENTION
During the production of fibers for paper making, wood or another fiber source is ground into chips and/or mechanically treated such that the chips may be broken down further and refined into individual fibers.
Disc refiners are used with high density stock containing forty to sixty percent fiber by weight to break down clumps of fibers into individual fibers. Disc refiners are also used with low density, low consistency pulp of two to five percent fiber dry weight to increase the freeness or bonding capability of the individual fibers.
The refiner disc consists of a disc-shaped steel or steel-alloy casting which has a multiplicity of more-or-more less radially extending bars cast on the surface thereof. One disc is mounted on a rotor for rotation and another disc is held opposed to the first refiner disc, either by rigid mounting or by mounting on an opposing rotating rotor. The refiner discs, as they move past each other, separate and refine the wood pulp as it passes between the opposed discs.
A refiner for high density stock employs an auger which is axially mounted with respect to the rotor on which the refining disks are mounted. Positioned adjacent to the end of the auger is a flinger nut which feeds the stock into a breaker bar section which in turn feeds the stock to the refiner disks where wood chips and clumps of fiber are broken down into individual fibers. Conventional flinger nuts employ radially extending vanes which become worn, necessitating expensive replacement of the flinger nut.
In the manufacture of paper, the cost of the stock or wood fibers used to manufacture the paper is the single largest component in the cost of the paper made. The paper fibers or stock is manufactured from wood chips which are in many aspects an industrial commodity whose price is governed by the market and not easily controlled. Thus, in improving the cost and efficiency of the papermaking process, it is important to focus on reducing the cost of processing the wood chips to produce the stock or furnish from which the paper is made. High density refiners which are used principally with mechanical or semi-chemical pulps are subjected to an intense wear environment. The wood chips which are fed to the refiner can contain sand and grit, which in the environment of the high density stock can produce relatively rapid ware.
What is needed is a flinger nut which can be efficiently maintained for improved wear life.
SUMMARY OF THE INVENTION
The improved high-consistency disc refiner of this invention employs a central ring or flinger nut, wherein radial vanes are releasably mounted to the flinger nut base.
A typical disc refiner employs a rotor mounted on a central axis within a housing. Stock enters the housing and is moved along the axis of the rotor by an auger. Mounted on the face of the rotor, facing the auger, is the central ring or flinger nut of the refiner. The job of the flinger nut is to initiate the radial acceleration of the high consistency stock along a radial plane defined by the rotor. As the stock moves along the rotor plane, the refiner discs mounted on the rotor and oppositely mounted fixed or counter-rotating refiner discs mounted on the housing break up and refine the wood chips and fiber clumps contained in the high-density stock.
In the process of papermaking, where wood in the form of logs is converted into fibers for the manufacture of paper, efforts are constantly made to remove foreign materials from the wood chips and fiber. This is done both to prevent these foreign materials from being incorporated in the finished product and also to prevent the damage that foreign materials cause to the pulp processing equipment. However, in the production of mechanical or semi-chemical pulp where the wood chips are mechanically treated prior to their complete dissolution into individual fibers, it is impossible to remove all sand and dirt which becomes attached or imbedded in the wood chip feed stock. The result is that the mechanical handling of wood chips necessarily results in the abrasion of the equipment employed.
The flinger nut of this invention has a base in which keyways are milled. Matching keys on the bottom of the flinger nut vanes position the vanes in the keyways on the flinger nut base. The flinger nut vanes are held in position by bolts which extend through bolt holes which are parallel to the axis of rotation of the rotor and which pass through the flinger nut vanes and are threadedly engaged with the flinger nut base. Because the flinger nut is often fabricated as a single, integral component, the normal procedure of replacing the entire nut requires extensive disassembly of the refiner, which can result in excessive down time.
The flinger nut of this invention, by employing replaceable vanes, not only reduces the cost of maintenance by allowing the replacement of only a part of the flinger nut, but generally also allow replacement of the vanes without removal of a flinger nut base. This reduces maintenance time and the costs associated with the unavailability of the refiner.
It is a feature of the present invention to provide a refiner employing a flinger nut with reduced maintenance costs.
It is a feature of the present invention to provide a refiner employing a flinger nut which improves the availability of the refiner.
It is a further feature of the present to provide a refiner employing a flinger nut of greater wear life.
Further features and advantages of the invention will be apparent from the following description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary cross-sectional view of a high-density stock disc refiner which is employed with the flinger nut of this invention.
FIG. 2 is an isometric view of the flinger nut with replaceable vanes of this invention.
FIG. 3 is a fragmentary exploded isometric view of the flinger nut of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to FIGS. 1-3, wherein like numbers refer to similar parts, a high-density pulp refiner 20 employing a releasably-mounted-vane flinger nut 24 is shown in FIG. 1. The refiner 20 has a housing 21 with an auger 22 mounted therein which supplies a high consistency pulp or stock from a stock inlet 23. Wood chip feed typically consists of forty to sixty percent wood chips and wood fiber in a medium of water. The auger 22 supplies stock to a center ring or flinger nut 24. The flinger nut 24 in turn passes the chips and fibers to a breaker bar section 26. The breaker bar section 26 leads into first refiner discs 28 and second refiner discs 30. The refiner discs are mounted to a rotor 32 parallel to a radially extending plane 34. The rotor 32 and refining discs 28, 30 rotate about an axis 36.
The auger 22 of the disc refiner 20 is mounted about the central axis 36 about which the rotor 32 rotates. The auger 22 moves high consistency pulp and wood chips from the stock inlet 23 to the central face 38 of the rotor 32. The auger 22 is disposed about a central shaft 40 which abuts the central face 38. Mounted on the central face 38 of the rotor 32, facing the auger 22, is the flinger nut 24 of the refiner 20. The flinger nut 24 initiates the radial acceleration of the high consistency stock along the radial plane 34 defined by the rotor 32. As the stock moves along the radial plane 34, the refiner discs 28, 30 mounted on the rotor 32 and on the housing 21 break up and refine the wood chip and fiber clumps contained in the high density stock.
The flinger nut 24 is composed of an annular base section 42, best shown in FIG. 2, to which are mounted four radially extending and axially protruding vanes 44. The base section 42 has a surface 82 which is approximately frustoconical, with the base section being thicker toward the central axis than away from it. The vanes 44 are spaced at equal angles from one another and extend from the inner circumference 46 to the outer circumference 48 of the base section 42.
Each vane 44, as shown in FIG. 3, is formed with a protruding key section 52 which is releasably mounted to the base section 42 by a key and keyway arrangement. Each vane key section 52 has a lower surface 54 and radially extending side surfaces 56 which are perpendicular to the radial plane. The key section 52 fits within a keyway 58 formed by portions of the base section 42. The keyway 58 has two side surfaces 60 which abut the side surfaces 56 of the key section 52 of the vane 44. The keyway 58 also has a bottom surface 62 which extends between the keyway side surfaces 60 and which engages the bottom surface 54 of the key section 52. Bolts 64 extend through bolt holes 66 in the vane 44. The bolts have threads 68 which are engaged with threaded holes 70 in the keyway bottom surface 62 of the base section 42. The key portion 52 of the vane 44 has a radiused inner circumferential surface 72 which forms part of the inner cylindrical circumference 46 of the flinger nut 24. The inner surface 72 is closely spaced from or abuts the central shaft 40 as shown in FIG. 1.
The vane bolt holes 66 are counter-sunk so that the bolt heads 65 are recessed below the upper surface 67 of the protruding blade 50 of the vane 44. The vane 44 has an outer radiused circumferential surface 74. The flinger nut 24 base section 42 is mounted to the rotor 32 around the central face 38 by bolts (not shown) which pass through holes 76 in the base section 42.
As it rotates, the motion of the flinger nut causes wood chips and wood fibers to press up against the sides 78 of the protruding vane blade 50. To prevent material from becoming jammed between the vane side surface 78 and the key surface 80 which generally conforms to the upper surface 82 of the base section 42 of the flinger nut 24, a curved transition section 84 extends between the key surface 80 and the surface 82 of the base section 42.
In the process of papermaking, where wood chips made from logs or wood wastes are converted into fibers for the manufacture of paper, efforts are constantly made throughout the manufacturing process to remove foreign materials from the wood chips and fibers. This is done both to prevent these foreign materials from being incorporated in the finished paper and to prevent the foreign materials from causing damage to the pulp processing equipment. However, where wood chips are processed, as in the high-density refiner 20, a certain amount of sand and dirt is invariably imbedded in the wood chips. Thus the feed stock supplied to a high-density refiner 20 necessarily creates an abrasive environment for the components of the refiner 20.
In practice, the vanes 44 of the flinger nut 24 experience wear which reduces their efficiency and necessitates periodic replacement. By employing replaceable flinger nut vanes 44, the cost of replacement parts due to flinger nut vane wear is reduced, since only the vanes and not the entire flinger nut 24 must be replaced. A second advantage is that where prior art flinger nuts were generally formed as a continuous section, the replacement of which requires more extensive disassembly of the refiner 20, the present invention allows replacement of the vanes alone. Vane replacement can generally be done without removing the flinger nut from the central shaft 40.
A third advantage is that the vanes 44 can be of varying types and configurations. Thus, they can be optimized more readily by the cost-effective trial of a number of vane designs. Further, in some circumstances, it may be advantageous to employ different vanes with different types of feed stock.
As shown in FIG. 3, secondary vanes 86 may be positioned between the vanes 44. The secondary vanes, while not essential, can improve the through-put of the flinger nut 24. There may be one, two or more secondary vanes 86 between the primary vanes 44. The secondary vanes may be welded in place as they will not necessarily wear as fast as the primary vanes 44. Alternatively, the secondary vanes may be attached by bolts (not shown) in a manner similar to the vanes 44.
It should be understood that the invention is not limited to the particular construction and arrangement of parts herein illustrated and described, but embraces such modified forms thereof as come within the scope of the following claims. | An improved high-consistency disc refiner employs a central ring or flinger nut. The radial vanes mounted on the flinger nut are releasably mounted to the flinger nut base in which keyways are milled. Matching keys on the bottom of the flinger nut vanes position the vanes in the keyways. The flinger nut vanes are held in position by bolts which extend through bolt holes which are parallel to the axis of rotation of the rotor and which are threadedly engaged with the flinger nut base. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 14/216,969 filed Mar. 17, 2014, which claims the benefit of priority to U.S. Provisional Application No. 61/790,771 filed on Mar. 15, 2013, the entirety of each are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The first portion of the background relates to passenger locomotive HEP and prime exhaust merging into a single main SCR system for lower emissions. Passenger locomotives are distinct from freight locomotives in that they have to provide not only tractive power from the prime engine to propel the locomotive, but also have to provide hotel power to provide lights and climate control for the passenger cars. Providing this hotel power is typically done with a second diesel engine and generator called a head-end power (HEP) generator.
[0003] In 2010 Metrolink tested a retrofit selective catalytic reduction (SCR) system on its F59PH locomotive SCAX 865. This system only treated the exhaust gasses from the 3000 hp main engine used for propulsion, the 250 kW HEP generator was not modified to lower its emissions. This demonstration program was funded by several agencies including the South Coast AQMD and CARB. It was designed, built and installed by Engine, Fuel and Emissions Engineering, Inc out of Rancho Cordova, Calif.
[0004] Two particular challenges came up in this testing program. The first challenge was low exhaust temperatures at throttle positions below notch 3 , and the second was the challenge of getting the UREA fluid to mix well with the exhaust gasses.
[0005] SCR systems from this same company will typically have NOx reduction efficiencies above 95%. Two conditions are required to meet this high efficiency level. The catalyst must be above a minimum operating temperature and the urea fluid must be vaporized and well mixed with the exhaust gasses. The base engine in this test program was tested at 9 g/(hp-hr) of NOx and the SCR system was able to reduce that to 2.6 g/(hp-hr), an overall emissions reduction efficiency of 71%. In order to achieve Tier 4 emissions levels of 1.3 g/(hp-hr) it would need an overall efficiency of 85%, which is well within the capabilities of the technology. Typical SCR installations would have a long mixing pipe that the exhaust gas and urea mixture would flow through before reaching the SCR substrates where the NOx reduction happens. A typical mixing duct has a length equal to 10 times its diameter.
[0006] Because of the tight packaging constraints of the locomotive, the SCR system was mounted immediately above the engine turbo charger outlet. At high loads and temperatures, the efficiency of this system was slightly above 80% instead of over 95% typical for an SCR system at operating temperature. These low efficiency numbers at higher operating temperatures illustrate the severity of the urea mixing issue and how it limited the overall efficiency of the SCR system.
[0007] In addition to poor urea mixing, low exhaust temperatures started to significantly affect the SCR system emissions reduction efficiency below throttle notch 4 ; at notch 3 the efficiency was reduced to 73% and by notch 2 it was down to 28%. At notch 1 and at idle the SCR system was inactive due to the SCR catalyst temperature being below the temperature required for thermal dissociation of the urea. The system was programmed to shut off urea injection under these conditions. It is these very low efficiencies at lower temperatures that brought the overall system efficiency down to 71% when at higher loads it was typically over 80%.
[0008] What is needed is an economical retrofit system for existing passenger locomotives that will solve these two system shortcomings so that the system will reduce NOx emissions below future EPA Tier 4 levels. It would also benefit the end user if this system could also help reduce the NOx emissions of the HEP generator.
[0009] The second portion of the background relates to combined cooling systems for PM emissions compliance and thermal efficiency. In the railroad industry, it has been a technique to reduce idling for many years by adding what is called an auxiliary engine to a locomotive to reduce the amount of time the main engine is idling. As far back as 1984, the Locomotive Cyclopedia had an advertisement for a system by Microphor. This reduction in main engine idle time saves wear and tear on the main engine, reduces emissions and saves fuel. When these auxiliary engines are liquid cooled they will transfer heat to the main engine coolant by transferring heat from both the auxiliary engine exhaust and the auxiliary engine coolant. These engines are typically very small, under 25 kW and these have typically been installed on freight locomotives.
[0010] As previously stated, passenger locomotives are distinct from freight locomotives in that they have to provide not only tractive power from the prime engine to propel the locomotive, but also have to provide hotel power to provide lights and climate control for the passenger cars. Providing this hotel power is typically done with a second diesel engine and generator called a HEP generator. Unlike auxiliary engines used for engine heating that are under 25 kW in power, HEP generators used in passenger locomotives are typically 250 kW or more. Currently Metrolink is specifying 600 kW HEP generators for new locomotives as they expect to be pulling longer trains with 10 passenger cars in the future.
[0011] Locomotives emissions requirements under EPA guidelines are different for HEP generators and auxiliary engines. A passenger locomotive engine that only provides hotel power does not fall under the locomotive emissions rules, but falls under off-road rules. If this engine performs any function beyond providing hotel power it will lose this exception and its emissions will somehow have to be combined with the prime engine emissions when emissions testing the locomotive engine. To this day, there has not been a passenger locomotive prime engine and HEP engine certified together; but the EPA regulations clearly acknowledge that a locomotive can be certified under an alternative duty cycle that would be developed for this specific application.
[0012] HEP generators are typically high speed diesel engines as used in class 8 trucks and capable of NOx emissions 85% below the locomotive Tier 4 standard and PM emissions 66% below the locomotive Tier 4 standard with the use of both an SCR system and a particulate filter system.
[0013] Engine, Fuel and Emissions Engineering Inc. has demonstrated a Compact SCR system for the EMD main engine that has the potential to reduce NOx emissions below Tier 4 levels with some further development. This Compact SCR system also has a section that acts as an oxidation catalyst that reduces particulate matter (PM). It is likely that this system with modern low oil consumption piston rings and liners will achieve PM emissions below Tier 3 levels, but not below Tier 4. Because of the scavenging nature of uniflow 2 stroke engines, they are not tolerant of significant increases in exhaust back pressure and it is impractical to put a particulate filter on them. This is a major reason why the 2 stroke truck engines were phased out by Detroit Diesel when the EPA starting imposing emissions limits on diesel truck engines.
[0014] It could be possible to economically retrofit older passenger locomotives to meet Tier 4 PM emissions levels if there was a practical way to combine the very low PM emissions level of the 4 stroke diesel particulate filter (DPF) equipped HEP engine with the slightly higher than Tier 4 PM emissions of an updated EMD 2 stroke prime engine.
[0015] The third portion of the background relates to combined high temperature and low temperature coolant loops with a thermal reservoir. Locomotives consume almost 5% of their fuel when powering the engine cooling fans. This energy could be saved by using ram air cooling, but that solution is not practical in rail applications for several reasons. First, freight trains can be moving slowly at high power for extended periods of time as when climbing a hill or starting from a stop with a very long train. Second, locomotives typically have to travel in either direction so the air ducting system would have to be bidirectional.
[0016] Passenger locomotives in commuter rail service do not have the issue of low-speed high-load operation for extended times. The passenger application is actually a higher speed application with frequent stops. With a high average speed the passenger locomotive would appear to be a good candidate for ram air cooling. But there is one issue. The higher speed operation of the passenger train where adequate ram air cooling is available does not occur when the locomotive is generating the most waste heat. The time when the most engine cooling is needed is when leaving the station after a stop and accelerating up to speed. This opposite timing of high cruising speeds and high engine loading makes using ram air cooling impractical even for this high average speed locomotive application.
[0017] Waste heat recovery is another technology that would be a good fit for passenger locomotives as they consume a lot of fuel and thus have a lot of waste energy to recover. They have steel wheels so the excess weight of the additional waste heat recovery equipment is not as much a detriment as it would be on a rubber tired on-road truck.
[0018] With the coming transition to natural gas and hybridization that will require a tender car, even the space is now available to install the needed ducting for bi-directional ram air cooling which could cool the prime engine and the HEP generator. But the opposite timing of high engine loading versus high speed makes it impractical.
[0019] What the locomotive system needs is a simple and reliable way to decouple the timing of when waste heat is created from when it can be rejected into the atmosphere.
BRIEF SUMMARY OF THE INVENTION
[0020] This application incorporates by reference the entirety of U.S. patent application Ser. Nos. 12/884,162 and 12/884,157.
[0021] The first portion of the summary relates to passenger locomotive HEP and prime engine exhaust merging into a single main SCR system for lower emissions. The basis of this invention is to combine the exhaust gases of both the prime engine and the HEP generator and run them together through a single SCR system. This harnesses the typically high exhaust temperature of the highly loaded HEP generator to keep the single main SCR system at operating temperature. This makes the SCR system effective at reducing the prime engine's emissions even when the prime engine is at idle or very low power.
[0022] The unique operating characteristics of passenger locomotives have the HEP generator continuously operating at 30% or higher engine loading. There will be instances in normal operations where the prime engine is shut down and the HEP generator is running, but there are no standard passenger operations where the prime engine is running and the HEP generator is not. This would typically only happen if the HEP generator failed and the locomotive was traveling to its next stop and then to a repair facility.
[0023] Because the HEP generator is always operating and operating at high exhaust temperatures, the urea needed to treat the prime engine exhaust can be injected first into the HEP engine exhaust and then mixed into the prime engine exhaust when the two exhaust streams converge. Because an HEP generator exhaust pipe will be 8″ in diameter or less, and there will be a long exhaust pipe from the HEP generator to the prime engine exhaust, there can be an effective mixing tube length well over the recommended 10 diameters for the urea to fully mix with the HEP generator exhaust.
[0024] This allows the use of a single urea injector for both engines, which is simpler and has fewer components that can leak, fail or require maintenance. The SCR control system will determine how much urea is needed for NOx reduction in both the prime and HEP engine exhaust streams and will inject that amount into the HEP exhaust stream.
[0025] This also solves the problem of the very short urea mixing pipe between the prime engine and the turbo hatch mounted main SCR. In this case the mixing length is close to one diameter, much less than the recommended 10 diameters.
[0026] With an improved exhaust urea mixture, the SCR system efficiency at high loads should approach its higher efficiency potential of 95-98%. With the continuous source of hot HEP generator exhaust mixed with the lower temperature exhaust of the prime engine, the low load SCR system efficiency should also be much improved.
[0027] In addition to improving the efficiency of the SCR system for the prime engine, the second locomotive engine is now operating at much lower NOx levels without the need to purchase a second SCR system or urea injector.
[0028] This also eliminates the temperature lag of the SCR system when it has been idling for a while. Passenger trains stop every few minutes and total idle time can be up to 3 minutes as a train starts to coast towards a station, decelerates gently as not to topple standing passengers and then sits for a minute as passengers get on and off. As the train pulls away from the station, the power is abruptly brought up to notch 8 to accelerate the train back to cruise speed. For busy commuter trains this could happen 100 times a day. With the current system, the SCR catalyst would take as much as 30 seconds to reach normal operating temperature. At the start of this warm up period the system would not be reducing NOx emissions at all, as the temperature is below the minimum temperature and the SCR controller will not inject urea. During the warm up phase the system would slowly start injecting more urea and the SCR system will start to become more efficient. Unfortunately a good deal of this time where the cold SCR is not working and starting to warm up is when it is needed most as the locomotive is at full power accelerating from a stop. With the HEP generator supplying a constant stream of hot exhaust and urea, the system will remain at or be very close to operating temperature through the entire deceleration, stop, and acceleration cycle.
[0029] Another advantage of the HEP generator keeping the SCR warm is the reduction in thermal cycling. With a commuter locomotive making up to 100 stops a day, the SCR substrates and all the metal structure and piping are being thermally cycled and stressed as they cool down at each stop. Using the HEP exhaust reduces the number of heat cycles to one or two cycles a day when the prime engine and HEP generator are combined. This could offer an order of magnitude increase in life of some of the components.
[0030] With future hybrid commuter locomotive systems on the horizon, this use of HEP generator exhaust heat will be even more important. Under a hybrid system, the need for power from the prime engine will be reduced or eliminated even sooner; and instead of idling the prime engine, it will be shut down. The locomotive will come into the station with the prime engine off and will likely leave the station under hybrid power without starting the prime engine. Instead of idling for 3 minutes, now the prime engine may be completely shut off for 4 minutes, then started back up and brought to high power. Without the heating of the HEP generator exhaust, the SCR system temperature cycle, length of time at high load operation and reduced SCR efficiency would be even greater.
[0031] The second portion of the summary relates to combined cooling systems for PM emissions compliance and thermal efficiency. Due to EPA locomotive regulations for auxiliary engines and hotel power, the HEP generator engine emissions can be combined with the prime engine emissions and be considered for an alternate duty cycle from the EPA. This emissions coupling is a result of using the HEP engine for more than just supplying hotel power which causes it to fall under the emissions requirements of locomotive auxiliary engines.
[0032] By eliminating the HEP engines radiator and redirecting the HEP engine coolant through the prime engine, the HEP engine is used as a heat source for both preheating the prime engine for starting, and also to keep it warm in cold weather so that its coolant won't freeze. This coupling of the coolant systems could be accomplished with just some simple piping modifications and a one-way check valve.
[0033] Without this system in colder climates, passenger locomotives would require an additional electric or diesel burner subsystem to preheat the prime engine or would use an additional heat exchanger and pump circuit to transfer heat from the HEP coolant to the prime engine coolant. These two approaches take up space and add maintenance requirements.
[0034] With the large radiating area of the prime engine and the main locomotive radiator system, it is likely that when the prime engine is idling or off, there will be no need to operate a powered cooling fan to cool the HEP engine. Powered cooling fans for a HEP generator would usually consume 5% or more of the generator output. As a HEP generator can contribute up to 33% of the total fuel consumption, a 5% decrease in HEP generator fuel consumption is a significant fuel and emissions savings.
[0035] The third portion of the summary relates to combined high temperature and low temperature coolant loops with a thermal reservoir. In addition to the thermal reservoir, the waste heat from both the low temperature and high temperature circuits are both rejected in a single radiator.
[0036] If this system only allowed the addition of ram air cooling, it would recover approximately 5% of wasted fuel energy consumed by the powered cooling fans.
[0037] If it additionally allowed waste heat recovery to be implemented it could recover an additional 10% of the fuel energy wasted as heat in the exhaust and jacket water.
[0038] As hybridization encourages turning off the main engine some distance before the locomotive reaches the station, this system will reduce the cold slug of engine coolant that a normal engine would get when first started after a sitting for a while.
[0039] With only one radiator, it will allow a locomotive to have both a low temperature and high temperature cooling circuit. This low temperature capability allows separate circuit aftercooling which increases power and efficiency and lowers emissions. This low temperature coolant circuit typically required an additional radiator.
[0040] Once the air to liquid cooling system has been located on the tender car, the thermal reservoir will allow the locomotive, when disconnected from the tender car, to be operated and moved short distances without the risk of overheating the engine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The drawing figures depict one or more implementations in accord with the present concepts, by way of example only, not by way of limitations. In the figures, like reference numerals refer to the same or similar elements.
[0042] FIG. 1 is a side view of an F59PHI passenger locomotive illustrating the combined exhaust systems feeding a single main SCR unit
[0043] FIG. 2 is a side view of an F59PHI passenger locomotive illustrating the prior art cooling system for the independent HEP and prime engines.
[0044] FIG. 3 is a system diagram for an embodiment of a multi-engine locomotive cooling system where a single radiator cools both engines and the smaller engine uses the bigger engine as a heat sink. This is illustrated as a modification of the cooling equipment in FIG. 2
[0045] FIG. 4 is a prior art passenger locomotive system with both a high and low temperature cooling circuit for both the HEP generator and the prime engine. In this case both the HEP engine and the prime engine have separate circuit aftercooling.
[0046] FIG. 5 is a system diagram of a multi-engine locomotive cooling system that has a single radiator and a thermal transient reservoir.
[0047] FIG. 6 is a side view of an F59 passenger locomotive to an advanced tender that incorporates bidirectional ram air cooling.
[0048] FIG. 7 is a side view of transit bus that incorporates a thermal transient reservoir and ram air cooling.
DETAILED DESCRIPTION OF THE INVENTION
[0049] To facilitate an understanding of the present disclosure, a number of terms and phrases are defined below:
[0050] Diesel particulate filter (DPF): is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine. Wall-flow diesel particulate filters usually remove 85% or more of the soot, and under certain conditions can attain soot removal efficiencies approaching 100%. Some filters are single-use, intended for disposal and replacement once full. Others are designed to burn off the accumulated particulate either passively through the use of a catalyst or by active means such as a fuel burner which heats the filter to soot combustion temperatures. This is accomplished by engine programming to run (when the filter is full) in a manner that elevates exhaust temperature or produces high amounts of NO x to oxidize the accumulated ash, or through other methods. This is known as “filter regeneration” and typically specified as either passive or active.
[0051] Cleaning and removal of accumulated ash is also required as part of periodic maintenance, and it must be done carefully to avoid damaging the filter.
[0052] Modern gasoline engines that use direct injection technology also need particulate filtering. As these units consume gasoline, the common nomenclature for them is a Gasoline particulate filter or GPF. In this document all particulate filtering devices will be generically referred to as a DPF. In any case where a specific type of particulate filter is discussed, it will be specifically named as needed.
[0053] Head End Power (HEP): passenger locomotives need hotel power for the passenger car climate control and lights. This is typically provided by a second diesel generator on a locomotive that outputs 480 volts AC at 60 Hertz in the united states, in Canada and Europe HEP power may be provided at a different voltage and frequency.
[0054] Particulate Matter (PM): Particulate matter is a criteria pollution emitted from many sources. In this document we will commonly refer to it simply as PM. It could include both diesel soot PM that is considered toxic in California or the type of PM created by the consumption and combustion of lube oil from an engine. While still considered PM as a criteria emission, the PM from lube oil consumption is considered less toxic than diesel soot.
[0055] Prime Engine: Locomotives may have several engines. The prime engine is typically the largest engine on the unit and is used mainly for providing tractive power for propelling the train. In a passenger locomotive there is typically a prime engine and an independent HEP engine for providing hotel power. In some cases a passenger locomotive may only have the prime engine and this engine will also provide hotel power in addition to tractive power.
[0056] Thermal Reservoir: A device set aside for thermal energy storage that functions similar to an electric capacitor, temporarily storing heat energy by raising the temperature of a unit of mass, and then dissipating that energy by lowering the temperature. A thermal reservoir could use many types of mass, two examples include a large metallic mass such as an engine block or a body of fluid in a holding tank. In some cases this body of fluid could also perform other functions. In one example the thermal reservoir consists of a tank of water, this water could also be the supply of water for water injection in the engine.
[0057] The first portion of the detailed description relates to passenger locomotive HEP and prime exhaust merging into a single main SCR system for lower emissions. FIG. 1 illustrates one embodiment of this system on an F59PHI locomotive.
[0058] For exhaust system clarity, this drawing has the prime engine 12 reversed with the turbo 6 at the rear end of the engine instead of at the front.
[0059] The F59PHI locomotive 10 , contains a prime engine 12 and a HEP generator 22 . SCR unit 1 is mounted to F59PHI 10 . Inside SCR unit 1 is where the NOx emissions are reduced. Turbo 6 is mounted to and accepts exhaust gases from prime engine 12 before passing them into main exhaust mixing duct 2 . Urea storage tank 7 provides the urea fluid that is injected by injector 4 into the HEP generator 22 exhaust gasses. The HEP generator exhaust gases first flow though DPF 5 and then enter HEP exhaust mixing tube 3 . Injector 4 injects the urea fluid into the HEP exhaust flow after it exits DPF 5 . The HEP 22 exhaust gases and injected urea are thoroughly mixed as they pass along HEP exhaust mixing tube 3 . At the end of HEP exhaust mixing tube 3 the mixture of exhaust gases and urea from HEP generator 22 are injected into the exhaust gases from prime engine 12 . These two exhaust streams are allowed to mix as they flow together along the main exhaust mixing duct 2 into SCR unit 1 .
[0060] In FIG. 1 the HEP generator 22 has a DPF 5 installed, another embodiment of this system would not have a DPF 5 installed and this would not affect the NOx reduction efficiency of the SCR unit 1 . This system with SCR unit 1 but not including DPF 5 would be used on a system that was only concerned with reducing NOx emissions or one that consumed a cleaner alternative fuel like natural gas and did not need to remove diesel particulates from the exhaust.
[0061] One embodiment of this combined exhaust system has the HEP generator exhaust injected into the rectangular turbine exhaust stack that is just above the prime engine turbocharger. The long dimension of the exhaust stack is aligned from side to side on the locomotive. It would be preferable to inject the HEP generator exhaust into the side of this stack. This area is just after the prime engine turbocharger turbine and is an area of high turbulence and swirl. Directing the HEP exhaust gases horizontally into this area will cause even more turbulence and result in very good mixing of the two exhaust streams.
[0062] Another mixing improvement could be to have the nozzle taper down in size where the HEP generator exhaust gasses mix with the prime engine exhaust gases. One embodiment could take a 6 inch exhaust pipe and have it taper down to 4.5 inches, this would almost double the velocity of the incoming HEP generator exhaust flow further increasing turbulence in the mixing area and improving the mixing of the exhaust streams.
[0063] Another embodiment could use multiple holes along the sides of the turbine exhaust stack. By having multiple points across the turbine exhaust stack the HEP exhaust will be injected at multiple different points into different parts of the prime engine exhaust flow stream. This will improve the mixing of the flow streams. It could also do this with less back pressure on either of the two engines.
[0064] The second portion of the detailed description relates to combined cooling systems for PM emissions compliance and thermal efficiency. FIG. 2 shows a prior art F59PHI locomotive 10 with both a prime engine 12 and a HEP generator 22 . The prime engine 12 provides tractive power for propelling the locomotive and the HEP generator 22 provides hotel power for the passenger cars. Heated coolant from prime engine 12 flows through coolant pipe 14 into main radiator 16 where heat is rejected from the coolant to the ambient atmosphere. This cooled coolant now flows back to the prime engine 12 through coolant pipe 20 . Coolant pipe 20 has pump 18 installed along it, pump 18 forces the coolant to recirculate thru this closed loop coolant circuit.
[0065] A second coolant system is installed with heated coolant from HEP generator 22 flowing thru coolant pipe 24 to the HEP radiator 26 . In HEP radiator 26 waste engine heat from the coolant is transferred to the ambient atmosphere. Cooled coolant then flows through coolant pipe 30 back into HEP generator 22 . Installed along coolant pipe 30 is pump 28 which forces the coolant to flow thru the closed loop coolant circuit just described.
[0066] HEP radiator 26 and main radiator 16 would typically have powered cooling fans to enable the heat transfer to ambient atmosphere, they are not illustrated here as they are common in the art and well understood. Also not included in these figures are means for controlling engine coolant temperature by decreasing or bypassing coolant flow as they are also common in the art and well understood.
[0067] FIG. 3 . Illustrates an embodiment of this invention, for clarity F59PHI locomotive 10 is not included in this drawing. Also missing from FIG. 3 is HEP radiator 26 as it is no longer needed with this new plumbing configuration. Added to this system is check valve 34 which is installed along coolant pipe 20 ′ upstream of pump 18 . The coolant flow for prime engine 12 is similar to the prior art in FIG. 1 as it flows in a closed loop thru coolant pipe 14 , main radiator 16 and back to the engine thru check valve 34 and pump 18 along coolant pipe 20 ′.
[0068] With the removal of the HEP radiator, the heated coolant from HEP generator 22 now flows through coolant pipe 24 ′ into coolant pipe 20 ′. At this point the heated HEP coolant mixes with the cooled coolant that is flowing back to prime engine 12 thru coolant pipe 20 ′. These two coolant streams mix together and are forced by pump 18 through prime engine 12 . The coolant leaving prime engine 12 now has the waste heat from both the HEP generator and the prime engine. Since the power output of the HEP engine is usually 10 to 20% of the prime engine, this added HEP waste heat mixing with the cooled coolant from radiator 16 is offset by lowering the temperature of the cooled coolant exiting radiator 16 .
[0069] The cooled coolant exiting radiator 16 flows thru coolant pipe 20 ′. Some of this flow will go through check valve 34 , but a portion of the flow will flow through coolant pipe 30 ′ and pump 28 back to HEP generator 22 . This portion of coolant flow will again absorb waste engine heat from the HEP generator and repeat the previous path through prime engine 12 to the main radiator 16 .
[0070] It is the simple addition of check valve 34 that allows the removal of the HEP radiator and combination of the two coolant systems. Check valve 34 prevents the heated HEP generator 22 coolant that flows through coolant pipe 24 ′ from flowing backwards through coolant pipe 20 ′ and then returning to the HEP generator 22 through coolant pipe 30 ′ without having rejected its waste heat in the main radiator 16 .
[0071] Future passenger trains are looking at HEP generators with power levels in excess of 600 kW. GoTransit currently specifies 720 kW. When the HEP generator power level and corresponding HEP generator coolant flow rate becomes so large that it is not practical to flow all of the HEP generator coolant through the prime engine, a bypass circuit can be installed around pump 18 and prime engine 12 . In this case a only a portion of HEP generator coolant would flow into pump 18 and the remainder would flow from coolant pipe 24 ′ over to coolant pipe 14 .
[0072] There are many ways to control this bypass flow known in the art, a 3 way control valve is one way. A controlled speed pump that forces the desired amount of HEP generator coolant into pump 18 as the remainder of the HEP generator coolant takes the path of least resistance through the bypass around prime engine 12 .
[0073] Another embodiment of this concept could be similar to FIG. 3 but have an added heat exchanger to exchange heat from the HEP generator to the prime engine. This added heat exchanger will keep the two engine coolant systems isolated and may be necessary if the two engines require different cooling fluids. Locomotives typically only use water with a corrosion inhibitor additive where HEP generators typically use a glycol based coolant. Coolant pipe 24 would flow heated HEP generator coolant through one side of this added heat exchanger and coolant pipe 20 would flow cooled coolant from radiator 16 through the other side of the added heat exchanger. This would transfer waste heat from the HEP generator coolant to the cooled coolant flowing into the prime engine. The main benefit of this system is the ability to preheat the prime engine coolant or keep the prime engine warm when it is not running As the prime engine coolant is also cooling the HEP generator, there will be energy savings in the reduction of the amount of power needed in the cooling fan used to cool the HEP generator radiator.
[0074] Another embodiment will have the same added heat exchanger as above, but will eliminate the radiator 26 for the HEP generator. In this case heated coolant will be routed through coolant pipe 24 , one side of the added heat exchanger and then back to the HEP generator through coolant pipe 30 . In this case all of the HEP generator waste heat will have to be absorbed by the prime engine coolant flowing through the opposite side of the added heat exchanger. This system has all of the advantages of FIG. 3 but keeps the two coolant circuits isolated. In this embodiment pump 18 on the prime engine will have to operate even when the prime engine is not operating. In FIG. 3 the pump 18 does not need to operate when the prime engine is off as pump 28 will cause the coolant to flow through pump 18 and the prime engine.
[0075] The third portion of the detailed description relates to combined high temperature and low temperature coolant loops with a thermal reservoir. FIG. 4 is a diagram of a typical prior art passenger locomotive cooling system for both the prime engine 12 and the HEP generator 22 . The prime engine 12 provides tractive power for propelling the locomotive and the HEP generator 22 provides hotel power for the passenger cars. Heated coolant from prime engine 12 flows through coolant pipe 14 into radiator 16 where heat is rejected from the coolant to the ambient atmosphere. This cooled coolant now flows back to the prime engine 12 through coolant pipe 20 . Pump 18 forces the coolant to circulate thru the closed loop formed by prime engine 12 , coolant pipe 14 , radiator 16 and coolant pipe 20 . In FIG. 4 . Pump 18 is mounted in coolant pipe 20 , but it could be mounted anywhere in the closed loop and still function. Control valve 15 acts to control the amount of coolant flow and therefore the temperature of the engine. In FIG. 4 control valve 15 is mounted on coolant pipe 14 , and similar to pump 18 , it could be mounted anywhere in the closed circuit coolant loop and still perform its function. In many instances known in the art, control valve 15 would be part of a bypass loop that allowed heated coolant water to bypass radiator 16 on its way to the inlet of pump 18 .
[0076] Prime engine 12 has a liquid to air aftercooler 42 which has its own cooling radiator 46 . The aftercooler 42 and radiator 46 will use coolant pipes 44 and 48 to form a similar closed loop coolant path as prime engine 12 . Pump 49 functions similarly to pump 18 to cause the coolant to circulate through this loop.
[0077] One engine having two cooling systems is not uncommon in modern high power diesel engines that are subject to emissions regulations. This is referred to as separate circuit aftercooling and is beneficial in reducing emissions. It is also further beneficial for natural gas engines as it reduces detonation and allows a higher compression ratio and thermal efficiency. These two cooling circuits have to be separate as the aftercooler needs cooled coolant that is as close to ambient temperature as possible, hence the low temperature circuit. The engine coolant on the other hand will still be relatively hot even after flowing through the radiator. It will only drop in temperature enough to dissipate the waste heat from prime engine 12 . This circuit is referred to as the high temperature circuit.
[0078] Fan 40 draws ambient air through both radiator 46 and radiator 16 . It is important that the ambient air pass through radiator 46 on its way to radiator 16 so that the low temperature circuit is cooled with the coldest air.
[0079] In a passenger locomotive there will be a second set of high and low temperature cooling systems for the HEP generator 22 . HEP generator 22 , coolant pipe 24 , radiator 26 and coolant pipe 28 form a closed coolant circuit similar to the coolant circuit for prime engine 12 . Pump 28 forces to the fluid to circulate in this closed loop and control valve 23 controls the flow amount and temperature. These components are located and function similar to their counterparts on prime engine 12 .
[0080] HEP generator 22 also has a liquid cooled aftercooler 34 . Aftercooler 34 , coolant pipe 36 , radiator 38 and coolant pipe 39 form a closed loop coolant circuit. Pump 32 forces the coolant to flow in this circuit and could be mounted anywhere in the closed loop circuit. A fan 40 draws ambient air first through radiator 38 and then radiator 26 to reject waste heat to the ambient atmosphere.
[0081] This figure describes what a modern coolant circuit will look like when a Tier 4 passenger locomotive is built with both a prime engine and a HEP generator. The current Tier 4 passenger locomotives being proposed no longer use a HEP generator, and will take hotel power from the main engine and convert it to AC using an inverter. Part of the reason for moving away from the separate HEP design is due to the complexity of having 4 separate cooling systems to allow both diesel engines to meet Tier 4 emissions levels.
[0082] FIG. 5 illustrates an embodiment of the transient thermal reservoir. This system cools both the prime engine 12 and the HEP generator 22 . As in FIG. 4 , each of these also has a low temperature circuit for the aftercooler and a high temperature circuit for jacket water cooling.
[0083] Compared to the system in FIG. 4 , this system has one less pump and eliminated 3 of the 4 original radiators. Added to the system is thermal reservoir 50 which is basically a tank of fluid. If water is used to absorb the thermal energy, 1000 gallons of it would weigh 9000 pounds and would absorb 173 HP continuously for an hour with only a 60 degree F. rise in temperature. Put in perspective, most locomotives carry in excess of 3500 gallons of diesel fuel and most passenger trains have enough clear space below the frame to add an additional 1000 gallon water tank which would be less than 5 feet long.
[0084] This system is one large closed loop low temperature coolant circuit formed by thermal reservoir 50 , coolant pipe 54 , coolant pipe 56 , radiator 16 ′, and coolant pipe 58 . Coolant travels from coolant pipe 54 to coolant pipe 56 through a pair of control valves and four heat exchangers. Coolant pipe 54 forms a pressurized manifold of low temperature coolant that will supply coolant to any of the waste heat sources that need cooling.
[0085] The waste heat sources are prime engine 12 and its aftercooler 42 plus the HEP generator 22 and its aftercooler 34 . Because the thermal reservoir 50 is a low temperature circuit and the jacket water cooling of prime engine 12 and HEP generator 22 need a high temperature circuit. Each will have its own closed coolant loop and a heat exchanger. There is a closed loop coolant circuit between Prime engine 12 and heat exchanger 60 . Pump 18 forces the fluid to circulate in this closed loop circuit. This pump should be the standard mechanically driven engine coolant pump, but it could also be an electric pump added for additional system control. Heat exchanger 60 is an interface between the high temperature coolant circulating in the prime engine 12 coolant circuit and the low temperature coolant being supplied by thermal reservoir 50 . Control of how much waste heat is removed from prime engine 12 is controlled by control valve 62 . As control valve 62 allows more cooled coolant to flow from coolant pipe 54 more waste heat will be removed from the high temperature coolant flowing in the prime engine 12 coolant circuit. After the low temperature coolant passes through heat exchanger 60 it enters coolant pipe 56 where it flows to radiator 16 ′ to reject its waste heat to the ambient atmosphere. Because aftercooler 42 is a low temperature heat exchanger, it will not need an interfacing heat exchanger and will take low temperature coolant directly from coolant pipe 54 . There is no control valve needed for aftercooler 42 as the goal is to have the coldest intake air possible.
[0086] HEP generator 22 has a similar coolant circuit design as prime engine 12 . Aftercooler 34 transfers waste heat to cooled coolant that it receives from coolant pipe 54 . This now heated coolant is sent to radiator 16 ′ to reject the waste heat. Heat exchanger 64 is used to transfer waste heat from HEP generator 22 to the cooled coolant in the low temperature coolant loop. One half of heat exchanger 64 and HEP generator 22 form their own high temperature closed loop coolant circuit. Pump 28 recirculates the coolant in this loop. On the other side of heat exchanger 64 , control valve 66 manipulates the amount of cooled coolant that flows through heat exchanger 64 , thereby controlling how much jacket water waste heat is removed from HEP generator 22 .
[0087] Heat exchanger 64 and HEP generator 22 form one independent closed loop high temperature coolant circuit, heat exchanger 60 and prime engine 12 form another independent high temperature closed loop coolant circuit. Thermal reservoir 50 coolant pipes 54 , 56 , 58 and radiator 16 ′ form an independent low temperature closes loop coolant circuit. This makes it possible to use different fluid compositions in three different closed loops. For most EMD locomotive retrofits is most likely that the low temperature loop and the prime engine 12 high temperature loop will operate with water as the coolant fluid and the HEP generator 22 high temperature circuit will run a glycol water mixture. It will be possible for any two loops operating on the same fluid to share a header supply tank if needed.
[0088] As a technique to reduce the energy consumption of powered cooling fans 40 and thereby save fuel, the powered fans will be operated at reduced power levels, possibly at less than 15% of rated power. When the locomotive is accelerating at full throttle radiator 16 ′ will not be able to reject all of the waste heat at this reduced cooling fan power. This will cause the coolant temperature in thermal reservoir 50 to rise during acceleration. After acceleration when the prime engine is at lower loads this reduced cooling fan capacity will be more than enough to reject the currently produced engine waste heat and at that point the coolant temperature in thermal reservoir 50 will start to drop. When the locomotive is stationary and the prime engine is at idle, the fluid temperature in reservoir 50 will drop even faster. If the distance between stops was long enough, the powered cooling fans may not even operate during the stop. Temperature control in reservoir 50 is controlled by manipulating the power input to the powered cooling fans. If sustained high load operations are happening such as climbing a long grade, the temperature in reservoir 50 may rise excessively. As the control system notices this rise in thermal reservoir 50 temperature it can incrementally increase fan power to keep the peak temperature under a certain threshold where higher thermal reservoir 50 temperatures would negatively impact either the engine emissions or the rated power level of the engines when operating on natural gas.
[0089] The benefits of this system are a possible 2% savings in fuel consumption by reducing the energy consumed by the powered cooling fans. Also this system allows having a low temperature loop and high temperature coolant loop for both engines using only one radiator. The prime engine will no longer be subject to a slug of cold water from the radiator at restart after sitting for a while.
[0090] FIG. 6 illustrates the use of a thermal reservoir system with a tender car which further reduces fuel consumption by using ram air cooling instead of powered cooling fans when the locomotive is as speed. Now that ram air cooling is practical, waste heat recovery can be implemented which further reduces fuel consumption and increases available power. Locomotive 70 is coupled to tender 72 . On locomotive 70 is prime engine 12 , HEP generator 22 and thermal reservoir 50 . Locomotive 70 will have the various configurations of heat exchanger, control valves and piping equipment that were previously described in FIG. 5 except for elimination of radiator 16 ′ and cooling fans 40 . The coolant that would have flown through radiator 16 ′ now flows through radiator 16 ″ on the tender car. To achieve this, coolant pipe 56 would connect to tender car coolant connector 76 taking the heated coolant to radiator 16 ″, and then coolant pipe 77 would return the coolant to coolant pipe 58 on the locomotive thus completing the closed coolant loop. The coolant pipes 76 and 77 on tender car 72 would have a flexible section needed to allow movement between the locomotive 70 and tender car 72 . Only one coolant pipe 76 or 77 is shown as they would be side by side. This version of the tender car is designed for ram air cooling with duct 74 allowing the airstream to flow through radiator 16 ″. Radiator 16 ″ could also be a conventional radiator similar to radiator 16 ′, but mounted in the roof of the tender car. In this case radiator 16 ″ would then need a set of cooling fans 40 to force the cooling air through it. Even in the case of a ram air cooling system configuration, there will likely be some kind of powered fan system for cooling at extended low speed operation or possibly climbing long hills.
[0091] In order to make efficient use of the ram air cooling, it is required to incorporate the combined closed loops as implemented in FIG. 5 . In FIG. 5 the powered fans can pull the ambient air through the radiators in the proper order at all times because the fans always move the air in one direction. In the bidirectional tender car, it both a high temperature and low temperature radiator is used; it is not possible to stack the radiators and insure that the ram air goes through the low temperature radiator first. If the ram air goes through the high temperature radiator first, the low temperature radiator will be less effective because the incoming cooling air will be heated up already. The likely solution would be to put the low temperature and high temperature radiators side by side, in this case the cooling air will only pass through one radiator and therefore twice as much cooling air will be required.
[0092] Another benefit of the combined low and high temperature circuits is only needing one pair of coolant lines between locomotive 70 and tender car 72 . If the high and low temperature circuits were independent then four coolant lines would be needed.
[0093] The installation of powered cooling fans poses a challenge for tender cars that are designed to use ram air cooling. Because locomotives and tender cars can travel in two directions, a ram air cooling system has to be bidirectional. Powered cooling fans designed to be efficient are only efficient in one direction. These fans will suffer poor efficiency if they are spun backwards to reverse the fan flow. Also if these fans are always present in the ducting, when not in use they will reduce the efficiency of the ram air ducting requiring either larger inlets and ducts or higher speeds to get effective cooling.
[0094] One solution is to have the fans installed in a panel that can rotate about its center axis so that its wide dimension is positioned parallel to the cooling air flow when powered fans are not needed. This also allows the fan panel to rotate 90 degrees in each direction so that the powered cooling fans can provide cooling air flow in either direction depending on the tender car direction of travel.
[0095] This method of pivoting the fan panel solves the bidirectional problem and the ram air duct blockage issue when powered fans are not needed. There is still a further problem in that powered fans cannot be used at low speeds to augment ram air cooling flow. There will be a speed range from just above stationary up to the speed where there is enough ram air supplied cooling to absorb the required waste. In this speed range it would be beneficial if the powered fans could be deployed and only use enough power to augment the ram air. Unfortunately when the fan panel rotates into position it will significantly reduce the flow amount of ram air provided by the trains velocity through the air, because of that the fans will have to operate at a much higher power setting than would otherwise be needed just to augment the ram air flow thus reducing the energy savings of the ram air cooling system. This is less an issue for commuter locomotives that will use a thermal reservoir and more an issue for freight locomotives that may travel at lower velocities for a longer period of time at high power such as when climbing a hill.
[0096] There is a novel way to do the powered cooling that eliminates the rotating fan panels for the bidirectional ram air cooling and at the same time allows the powered fan system to augment the ram air supply at lower speeds. Instead of the fans moving all of the air in the duct, the fan supply could be ducting into an air amplifier system. This would function something like a Dyson AM2 air multiplier home fan. This would use pressurized air being forced though small slits in the duct walls to flow over a curved surface using the coanda effective to entrain more air and assist in driving the ram air supply through the duct. In this system smaller fans supply less air mass at a higher pressure to be ejected out of these slits at a high velocity. It is this high velocity air that transfers some of its kinetic energy to the air around it, hence amplifying its own air flow. Using the Dyson AM02 tower fan as an example these slits could be designed into the duct wall, and additional stationary panels that are parallel to the air flow could have additional slits to create multiple air amplifiers across the width of the duct.
[0097] The slits will efficiently work in one direction, and when the airflow is traveling in the opposite direction, the slits will offer negligible resistance to the opposing air flow. This allows the powered cooling system to be efficiently used from very low power up to maximum power. By using air shut off valves to control the flow to individual slits or groups of slits, the slits can be brought into action a few at a time which allows them to run at high velocity, but only use enough fan power to supply the needed number of slits.
[0098] For powered fan cooling in both directions, one set of slits will be designed to amplify air in each direction. A single fan could supply the pressurized air for all of these slits. The direction of effective cooling air flow could then be controlled by one large three way valve that either supplies one cooling direction or the other. It could also be multiple shut off valves with only the particular valves opening for the correct direction and also only the number of valves opening for the number of same direction slits needed for desired total cooling air flow.
[0099] This same multiple slits along the duct walls and additional panels with multiple shut off valves could be used in the ram air ducting on the roof of a transit bus, but this system will only need slits that amplify air in one direction.
[0100] FIG. 7 illustrates the concept of using a thermal reservoir 99 on a transit bus 90 . Transit busses are another stop and go application where a thermal reservoir system could save significant energy by decoupling the time where it is cooling the thermal reservoir fluids at higher speeds while generating more waste heat at lower speeds when accelerating. Because transit busses also have to operate an air conditioning system condenser with a powered fan, the wasted energy for a transit bus can be 10% or higher of the fuel consumed.
[0101] In order to make a thermal reservoir work on a transit bus with ram air cooling, an overhead duct system 92 would be employed with ram air 94 entering from the front of the bus due to forward velocity. The height of this duct system is not a clearance issue for transit busses as they typically store CNG cylinders on the roof. In order to allow airflow through duct system 92 , the CNG cylinders are stored length wise along the direction of the air flow. Typically they are stored from left to right which would block off the air flow. Radiator 98 would be towards the end of the duct system 92 . The thermal reservoir 99 would most likely be mounted under the floor of the bus where it would have the least effect on the bus center of gravity.
[0102] This is another example of where a thermal reservoir makes practical both the application of ram air cooling and waste heat recovery. If the waste heat recovery system had to be cooled by a powered fan it would expend most of its recovered energy in fan power. This combination of ram air cooling and waste heat recovery would be a good fit with a hybrid bus. In a hybrid bus, the engine and the waste heat recovery system would operate at a near constant load and high efficiency with the hybrid system taking care of the transient loading of the bus and the thermal reservoir dissipating the remaining waste heat at higher average speeds.
[0103] This system could also be implemented as a ram air cooling system without the thermal reservoir using the slit cooling system to increase air flow at a stop or low speeds. With the thermal reservoir the powered slit cooling system would be rarely used. Without the thermal reservoir, the powered fan would cycle frequently. A system with a small thermal reservoir would cycle the powered cooling fans less often. In the transit bus without a thermal reservoir, the high temperature and low temperature circuits can have their own radiators because the air flow is always in one direction and the radiators can be stacked appropriately.
[0104] It should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. | A system includes a prime engine connected to a prime engine exhaust stack that receives prime engine exhaust, a mixing duct section connected to the prime engine exhaust stack, a head-end power (HEP) generator connected to an HEP generator exhaust pipe that receives HEP generator exhaust, a single urea injector, and a selective catalytic reduction (SCR) system. The HEP generator exhaust pipe is connected to the mixing duct section, and the single urea injector injects urea into the HEP generator exhaust pipe upstream of the mixing duct section. The HEP generator exhaust and prime engine exhaust merge in the mixing duct section to form a merged exhaust that is received by the SCR system. | 5 |
BACKGROUND OF THE INVENTION
The present invention pertains to a downhole energy absorbing system for generation of electrical power, and more particularly to an apparatus for absorbing at least a portion of the vibrational energy from a drill string and converting such vibrational energy into electrical energy.
The problem of developing effective downhole electrical power supplies has existed in the mining and petroleum industries since the advent of downhole electrically operated devices. To a great extent, the development of electrically operated downhole equipment has been stymied by the lack of an effective power supply which will operate within the restrictive limitations of the downhole environment. In the past, great reliance has been placed on batteries for downhole power but the environment of a wellbore, particularly with respect to high temperatures and pressures, as well as space limitations, all mitigate against the use of batteries, especially where sustained power is required. As a result of the ineffectiveness of battery power for many such operations, most measuring techniques, especially during drilling operations, require the cessation of drilling while electrically operated apparatus is lowered into the borehole on an armored cable having one or more electrical conductors.
With the advent of deeper drilling and increased drilling activity offshore and in hostile surface environments, the costs of drilling have escalated substantially. Therefore, any operation which requires the cessation of drilling in order to be performed, such as lowering a cable into the borehole, is done at a great expense. In addition, because of the great expense of present drilling operations, the need has increased for obtaining real time data concerning downhole conditions, while drilling is progressing.
As a result, a great deal of development activity in the petroleum industry has been directed toward various telemetry systems for transmitting downhole data, relating to parameters measured while drilling, to the surface. Except for special circumstances, current methods of transmitting real time data in measure-while-drilling (MWD) systems have been marginally effective. Examples of important measurements to be made during drilling include rotation rate, penetration rate, torque, borehole fluid invasion, bit wear, formation parameters, etc. Presently in commercial use are mud pulse systems for telemetering data from the bit vicinity to the surface; however, these systems are expensive to use and have a low data rate.
There are basically four types of systems which show promise as communication and transmission systems in a borehole telemetry system. These are mud pressure pulse systems (mentioned above), electromagnetic methods, insulated conductor or hardwire systems, and acoustic methods. Developments in the last three methods have indicated the need to provide repeaters in the system in order to boost the signal as it is attenuated over a long and sometimes resistive conductor path. It appears that acoustic signals for example may travel effectively, under general drilling conditions, for 2 or 3 thousand feet before they are attentuated to unusable levels. The same is true of electromagnetic schemes. A hardwire system disclosed in U.S. Pat. No. 3,090,031 uses induction coupling between joints of pipe and electronic circuitry which necessitates the use of power sources at each coupling. In all of the proposed systems, excepting perhaps the mud pulse system, electrical power generation downhole to operate downhole circuits, including repeaters, presents a particularly difficult problem. The disadvantages of batteries have been discussed above. Present downhole generators typically rely on impellers or turbines stationed in the mud flow path to develop power. This tends to obstruct the full open bore in the pipe string, which may impede the insertion of equipment into the borehole through the drill pipe. In addition, such generators are adversely affected by the abrasive nature of drilling fluids which tend to wear flow channels and blades typically used in such devices and to damage bearings or the like.
In addition to the problem of effectively generating electrical power downhole in MWD systems, the vibrational environment afforded by the drill string is particularly harmful to electrical and mechanical hardwire systems associated with the measuring and telemetering of measured data to the surface in a drilling operation. As the formation is being drilled, an irregularly shaped hole bottom develops which causes the bit to rise and fall with rotation of the bit. This in turn causes the bit loading to vary. The variable load at the bit may be caused by other factors also. Thus conditions exist downhole which make the bit produce irregular demands on power, thus rendering the drill bit as a driver of drill string vibrations.
Additionally, the rotating drill string causes gyrations of the bottom hole assemblies above the drill bit which are transmitted to the bit in the form of load and torque variations. Thus, the drill string itself induces irregular power into the bit and thereby becomes the driver of drill string vibrations. In any event such vibrations cause fatigue forces to develop on the drill string and bit, increasing wear on the system as well as damaging mechanical and electrical components associated with a MWD system.
In order to minimize the effects of vibrational forces on a drill string and associated down hole assemblies, various shock absorbing assemblies have been developed for incorporation in the drill string, usually above the drilling bit, to isolate induced vibration, shock and impact loads from the drill string above the bit. Normally such shock absorbing subassemblies utilize a splined engagement between a mandrel and an elongated body, whereby drilling or rotational torque is transmitted through the splined engagement between the mandrel and the body. The splined section also permits longitudinal movement of the body with respect to the mandrel, to apply impact or longitudinal vibrational loads to a shock absorbing element, such as a spring system, in the subassembly. A shock absorbing subassembly of this type is disclosed in this inventor's U.S. Pat. No. 4,246,765 dated Jan. 27, 1981.
Keeping in mind the dual problems of dampening vibrations in a drill string to prevent fatigue to the drilling and instrumentation hardware in a drilling system and the need for a reliable downhole power supply, it is an object of the present invention to provide a new and improved downhole assembly for absorbing at least a portion of the vibrational energy occurring on a drill string and converting such absorbed energy into electrical energy to power downhole electrical devices.
SUMMARY OF THE INVENTION
With this and other objects in view, the present invention contemplates apparatus for use in a drill string operating in a borehole including a body portion and mandrel portion of a subassembly arranged for longitudinal movement relative to one another and having threaded end portions for assembly in a drill string. The mandrel and body portions are telescopically arranged to provide an annular chamber between which houses an energy absorbing mechanism. Matingly engaging splines on the mandrel and body portions respectively, permit rotational torque to be transmitted between the mandrel and body portions for transmitting unidirectional rotational motion through the drill string. The energy absorbing mechanism housed between the respective portions has means for converting vibrational motion into electrical energy. This electrical energy is then transmitted in usuable form to an electrically operated device.
One aspect of the invention resides in the use of a piezoelectric device as the energy absorbing mechanism and as the means for converting vibrational energy, in the form of cyclic motion, into electrical energy. Such piezoelectric device may be in the form of a stack of piezoelectric elements arranged in an electrically additive configuration. The output of the piezoelectric device may also be rectified and filtered to provide a usuable form of electrical energy to the using electrical apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic elevational view of a drill string incorporating a telemetry system including an energy absorbing and power generating system in accordance with the present invention;
FIG. 2 is an elevational view in cross section of an energy absorbing and power generating subassembly in accordance with the present invention;
FIG. 3 is an elevational view in cross section of an alternative embodiment of a power generating subassembly;
FIG. 4 is an enlarged partial cross sectional view in elevation of a piezoelectric device for converting cyclic mechanical energy into electrical energy; and
FIG. 5 is a schematic electrical equivalent circuit of a piezoelectric element.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 of the drawings, a drill stem 12 is shown suspended in a borehole 13 penetrating earth formations 14. The drill string extends to the surface of the borehole, where it is connected to conventional drilling support apparatus (not shown). The drill string of FIG. 1 includes a bit 16 which may be rotated in the borehole by rotating the drill string or by use of a mud motor, turbine, or the like (not shown) to penetrate into the earth formation. Positioned above the bit is a vibration absorbing and electrical power generating subassembly 17 in accordance with the present invention, which will be described in greater detail with respect to the remaining figures of the drawings. Above the power generating subassembly 17 is a sub 18 for housing electrical controls to modify the output of the power generating sub. Such controls would typically include a rectifier for changing the sinusoidal output of the power generating sub 17 into a direct current. Sub 18 may also include filter and voltage regulator circuits for further modifying the electrical output of the power generator to place such electrical output in a form usable in typical downhole circuitry. The nature of such modifying control circuits will of course depend on the use of the generated electrical power and will be incorporated in the sub 18 accordingly. A sensor subassembly 19 is next positioned in the drill string, typically in a non magnetic drill collar to provide an environment free of magnetic influences in which to operate instruments for measuring borehole parameters or the occurence of events to be telemetered to the surface. Such parameters and events, which it may be desirable to present as real time data at the surface, are too numerous to list fully; however, they would include: bit orientation, bit wear, rotation rate, torque, borehole fluid invasion parameters such as fluid resistivity, formation parameters derived from various formation logging techniques, etc.
A data telemetry system is schematically represented by the sub 21 above the sensors 19 for transmitting data measured by sub 19 to the surface. Such data telemetry may be accomplished by any of the telemetry systems discussed in the background of the invention such as the hardwire telemetry system disclosed in U.S. Pat. No. 3,090,031 to Lord, or an acoustic telemetry system as set forth in U.S. Pat. No. 3,930,220 to Shawhan. In any event, the data telemetry system 21 provides a means for encoding data gathered by the sensors 19 into a transmittable format consistant with the type of telemetry system used, and sending such data uphole by suitable means.
Typically the drill string 12 will include a number of drill collars 22 and intermediate pipe sections (not shown) for adding weight and stiffness to the bottom end of the drill string. Proceeding up the drill string, sections of drill pipe will complete the drill string to the surface, with such sections of pipe normally being approximately 30 or 45 feet in length. Repeater subs 24 may be intermittently stationed in the drill string between sections of pipe, depending on the type of telemetry system in use in the MWD system. Repeaters are typically used in acoustic and electromagnetic telemetry systems as shown in the aforementioned U.S. Pat. No. 3,930,220 and may also be incorporated in a hardwire systems. Such repeater subs are further pertinent to the present invention in that the power generating apparatus disclosed herein may find use as a means for providing electrical power to such repeaters.
Referring next to FIG. 2 of the drawings, the vibration absorbing and power generating subassembly 17 is shown in detail. The subassembly 17 comprises a mandrel 40 and a body 50. Body 50 has a longitudinally extending bore 51 in which mandrel 40 is received, forming an annular chamber 52 between mandrel 40 and body 50.
Mandrel 40 is shown having a threaded box end connection 41 at its upper end for accommodating assemblage of the subassembly in the tool string. Mandrel 40 is prevented from rotating within body 50 by means of a plurality of longitudinally extending splines 45 which are matingly received within longitudinally extending grooves 53 formed on the wall of bore 51 of body 50. Mandrel 40 is also provided with additional splines 46 for cooperation with a split ring 47 and split ring retainer 48. Split ring 47 has a circumferential groove 49 which encloses splines 46 of mandrel 40. Mandrel 40 also includes a removable washpipe 90 threadedly received on the lower end of mandrel 40.
It is seen that mandrel 40 and washpipe 90 are provided with a longitudinally extending bore 92 which allows a suitable drilling mud (not shown) under high pressure to pass downwardly through the drilling string 12, including subassembly 17, and to the bit 16.
Body 50 includes drive sub 60, a main body portion 70, and a bottom sub 80. Drive sub 60 is connected to main body portion 70 by a suitable threaded connection, and bottom sub 80 is likewise connected to main body portion 70 by means of a suitable threaded connection. Bottom sub 80 is provided with internal threads 82 for enabling shock absorbing subassembly 17 to be attached to a suitable tool joint box (not shown). Bottom sub 80 further includes suitable sealing means 83 disposed in interior circumferential grooves of bottom sub 80 for providing a seal between the washpipe 90 of mandrel 40 and bottom sub 80 of body 50. It should be noted that sealing means 83 cooperates with the circumferential outer wall of washpipe 90, and provides for a seal to be effected about the smaller circumference of washpipe 90, rather than about the larger circumference of main mandrel portion 40, thus reducing the amount of hydraulic force action on the mandrel.
Drive sub 60 is provided with interior radial grooves in which sealing means 63 are inserted, thus providing a seal means between mandrel 40 and drive sub 60 of body 50 to seal off annular chamber 52 from the exterior of body 50. Drive sub 60 may further be provided with an oil inspection hole and plug (not shown) to enable annular chamber 52 to be filled with oil, as to be hereinafter described. As previously discussed, drive sub 60 includes the longitudinally extending grooves 53 for cooperation with splines 45 of mandrel 40, whereby mandrel 40 is non-rotatably received in body 50 and allows the transmission of torque to be applied to the subassembly 17 as a rotational force is applied to mandrel 40 via the drill string connected thereabove. Longitudinally extending grooves 53 of drive sub 60 additionally allow a longitudinally sliding engagement between mandrel 40 and body 50, thus limited relative longitudinal movement between mandrel 40 and body 50.
Main body portion 70 is also provided with oil inspection holes and plugs for allowing chamber 52 to be filled with oil as to be hereinafter described, and may also include a plurality of vent holes 55 which communicate with the lower portion of annular chamber 52.
Main body portion 70 is provided with an interior circumferential depending flange 56, the top surface 57 of which forms a load transmitting surface within chamber 52 for transmitting longitudinal thrust loading between mandrel 40 and body 50. Load transmitting surface 57 cooperates with shock absorber element 110, which is disposed between load transmitting surface 57 and its opposed load transmitting surface 58, which is on the lower end of split ring 47 associated with mandrel 40.
The shock absorber element 110 within chamber 52 between opposed load transmitting surfaces 57 and 58 comprises a ring spring assembly 112, thrust ring 113, and spring mandrel 114. The ring springs of ring spring assembly 112 comprise alternating closed out and inner rings with tapered contact surfaces. Spring mandrel 114 provides a means for mounting the ring springs of shock absorber element 110 about mandrel 40, and spring mandrel 114 is slidably mounted about mandrel 40 within annular chamber 52.
Spring mandrel 114 serves the following functions of providing support or stabilization to mandrel 40 in main body portion 70; acts as a centralizer or keeper for the set of ring springs 112; and, in combination with thrust ring 113 and opposed load transmitting surfaces 57 and 58, provides an overload stop, whereby a body 50 slides relative to mandrel 40, thus compressing shock absorber element 110; the maximum amount of compression of shock absorber element 110 is predetermined by the length of spring mandrel 114. Spring mandrel 114 is provided with suitable openings or vents to allow the passage of lubricating oil to fill the entire cavity 52, thus bathing the elements within chamber 52 with oil to lubricate the moving elements therein and to dissipate the effects of heat and friction generated by the compression of the sets of ring springs 112. Thrust ring 113 may likewise be provided with a suitable vent or opening for the same purpose.
Subassembly 17 is provided with a floating seal assembly means 100 in the lower portion of annular chamber 52 for sealing off chamber 52, while still allowing for fluid movement of the lubricating oil in chamber 52 occurring during deflection or relative movement of the mandrel 40 within body 50. The floating seal assembly means 100, or floater, is slidably received between washpipe 90 and main body portion 70, and includes washpipe seals 101 mounted in interior circumferential grooves, and body seals 103 mounted in outer circumferential grooves. Floater 100 may tend to move longitudinally of body 50 with the deflection or relative movement of the mandrel 40 within body 50. The floater 100 also compensates for thermal expansion of the hydraulic fluid, such as oil, within the annular chamber 52 defined between floater 100 and seals 53 between drive sub 60 and mandrel 40.
A top portion of annular chamber 52 above spring mandrel 114 is sized to receive a stack of preassembled piezoelectric elements 111. The piezoelectric assembly 111 will be described in more detail with respect to FIG. 4. The assembly 111 is arranged in the space between spring mandrel 114 and load transmitting surface 58 on the bottom of split ring 47.
To assemble the subassembly 30 of the present invention, washpipe 90 is threadedly connected to mandrel 40. Drive sub 60 of body 50 is then placed onto mandrel 40 with the seals 63 already assembled therein, and with interior grooves 53 of drive sub 60 meshing with splines 45 of mandrel 40. Then split ring 47 is mounted about mandrel 40 with interior groove 49 of split ring 47 enclosing splines 46 of mandrel 40. Split ring retainer ring 48 is then mounted about split ring 47, whereby longitudinal sliding movement of drive sub 60 relative to mandrel 40 is limited. Spring mandrel 114 with the piezoelectric assembly 111 and the set of ring springs 112 is then placed about mandrel 40 and thrust ring 113 is then disposed about the lower portion of mandrel 40. After those elements are in position, main body portion 70 is assembled about mandrel 40 and shock absorber element 110. Main body portion 70 is then threadedly connected to drive sub 60 via threaded connection. Floater 100 is then inserted into main body portion 70 about washpipe 90. Bottom sub 80, with seals 83 already assembled therein, may then be threadedly connected to main body portion 70 via its threaded connection, whereby it is in sliding contact with washpipe 90 of mandrel 40. The subassembly is then filled with oil through the oil plug in drive sub 60 (not shown), and after the subassembly is filled with oil, a vacuum may be applied via the oil plug to ensure that all entrapped air has been removed from chamber 52, and that the chamber 52 is completely filled with oil. The shock absorber element 110 may be provided with a preloaded assembly.
Referring next to FIG. 3 of the drawings, a power generator device, arranged similarly to the subassembly described in detail with respect to FIG. 2, is shown without the provision of the shock absorbing element 110. Instead, the subassembly has been shortened to include the piezoelectric stack 111 arranged between the thrust ring 114 and load transmitting surface 58 on the bottom end of split ring 47. Thrust ring 113 is arranged to rest directly on top of flange 56 thus eliminating that portion of chamber 52 of FIG. 2 for housing the shock absorbing element 110. As in FIG. 2, mandrel 40 is telescopically received within body 50. Mandrel 40 has washpipe portion 90 extending downwardly from its lower end, and bore 92 within the mandrel to provide a mud circulation passage in the drill string. Body 50 includes drive sub 60, main body portion 70, and bottom sub 80 all threadedly connected to one another to comprise the body 50. Drive sub 60 is provided with interior sealing means 63 to provide a sliding sealing surface between drive sub 60 of body 50, and mandrel 40, to seal off the upper end of annular chamber 52.
Drive sub 60 also includes an arrangement of grooves 42 for matingly engaging splines 43 on the mandrel 40. The arrangement of grooves and splines in FIG. 3 may be longitudinally arranged as in FIG. 2 to permit relative longitudinal movement between the mandrel 40 and body 50 or alternatively, they may be helically arranged to permit both longitudinal and rotational relative movement between mandrel 40 and body 50. Also to facilitate such rotational and longitudinal movement, coarse multiple lead threads may be employed between the mandrel and body. Such an arrangement will permit the transmission of torque as well as longitudinal forces when the load bearing surfaces of the assembly are fully engaged while permitting vibrational motion of both a rotational and longitudinal nature to be absorbed by the piezoelectric stack 111 arranged between the load bearing surfaces. The main body portion 70 is again provided with oil inspection holes and plugs (not shown) for filling chamber 52 with oil. Vent holes 55 are also provided in body 70 to communicate with the lower portion of chamber 52. The top surface 57 of flange 56 forms a load transmitting surface for transmitting longitudinal thrust loading between mandrel 40 and body 50. Load transmitting surface 57 cooperates with thrust ring 113 and piezoelectric stack 111 which are disposed between surfaces 57 and its opposed load transmitting surface 58.
Floating seal assembly 100 is also again disposed in the lower portion of chamber 52 for sealing of the lower end of the chamber and at the same time allowing movement of oil in chamber 52. Seal assembly 100 also allows for thermal expansion of the hydraulic fluid in annular chamber 52. The assembly of the parts in FIG. 3 is similar to that described with respect to FIG. 2. Referring next to FIG. 4 of the drawings the piezoelectric evice 111 is shown in detail as being in the form of a cylinder comprising an outer cylindrical housing 64 and inner cylindrical housing 66 spaced inwardly from the outer housing 64 to form an annular chamber 67. The upper and lower ends of chamber 67 are covered by top and bottom end caps 68 and 69 respectively. An inner peripheral groove 71 is formed in the side wall of the upper and lower end cap 68 and 69 for receiving circular O-ring seals 72. Likewise, a peripheral groove 73 is formed on the outer side wall of each of the end caps 68 and 69 for receiving circular O-ring seals 74. The seals 72 and 74 are arranged between the end caps and inner and outer housing 66, 64 respectively to provide a fluid tight environment within the chamber 67. Upper end cap 68 is provided with vertical and radial passageways 76, 77 respectively, connecting the exterior of the end caps with the interior of chamber 67. Each of the end caps has a radially extending outer flange portion 78. When the end cap is assembled on the inner and outer housings 66, 64, a longitudinal clearance 79 is provided between the flange portion 78 and the ends of cylindrical housing 66 and 64. This clearance permits compressive loads to be transmitted from the end caps to piezoelectric cylindrical element 81 which are stacked adjacent one another within the chamber 67, between top and bottom end caps 68 and 69. The seals 72 and 73 permit relative longitudinal movement between the end caps and housings while maintaining a fluid sealed environment. Although four piezoelectric cylinders are shown comprising the stack of FIG. 4, it is readily appreciated that any number of cylinders can be arranged in such a configuration to comprise a stack. In this respect, the cylindrical shape of piezoelectric elements is choosen to provide a high density ratio of piezoelectric material to space available in the confining environment of a borehole sub. Other geometrical configurations of piezoelectric elements and arrangement of stacks may be employed to accommodate specific considerations. One such alternative arrangement of piezoelectric elements is shown in a co-pending U.S. patent application filed on the same date of this application.
An inner insulating cylinder 82 constructed of a suitable insulating material is arranged between the inner cylindrical wall portions of the piezoelectric elements 81 and the outer wall of inner cylindrical housing 66. Similarly, an outer insulating cylinder 83 is arranged between the outer wall portions of the piezoelectric elements 81 and the inner wall of outer cylindrical housing 64. To completely insulate the piezoelectric stack of elements 81 from the sealed housing confines, top and bottom insulating discs 86 and 87, of a circular configuration, are positioned between the end caps and the top and bottom of the piezoelectric stack respectively.
Conductor wires 88 extend from the top and bottom surfaces of each of the piezoelectric elements 81 and are connected in parallel or series-parallel configuration to provide an appropriate additive value of voltage or current to facilitate the particular usage of generated electrical energy in the downhole systems. The conductors 88 are arranged to extend through a plug 89 which seals about the conductors and within the upper end of passage 76, to maintain the sealed integrity of inner chamber 67. In this respect the split ring 47 (FIGS. 2 and 3) may have an appropriate cavity formed therein to facilitate the upward extension of the plug 89 therein and the passage of conductors 88 for connection with the electrical control sub 18 positioned above the vibration absorbing and power generating sub 17.
The principle of operation of the stack of piezoelectric elements 81 as described with respect to FIG. 4 may be explained by considering the behavior of a single piezoelectric disc of area A, thickness T, and specified physical properties. The disc is exposed to a sinusoidal pressure P at angular frequency w. Using a simplified equivalent circuit shown inside the dotted lines of FIG. 5 of the drawings, one can compute the power delivered to a load resistance R when the open circuit voltage generated is V and the piezoelectric disc capacitance is C. The potential across the load resistance is E. Power delivered to load R equals ##EQU1## where V=pg 33 t. g 33 is a constant of the material. There are a number of parameters which can be adjusted to optimize the use of such a device according to the requirements for power and available physical space. With respect to pressure, the open circuit voltage V increases linearly with the driving pressure and the power in turn increases as p 2 . Increasing the frequency w will permit a proportionate decrease in C, thereby reducing the total volume of piezoelectric material to achieve the same value of wRC. As the dielectric constant of the piezoelectric material increases, a smaller volume (total area at given thickness) of piezoelectric material is required to achieve a given value of C. Increasing the pressure constant g 33 has the same effect as increasing pressure. A monolithic layered structure can be built to reduce the volume of piezoelectric material for a given value of C. The limit on thickness reduction may be governed by minimum voltage requirements in some situations. For given material properties the open circuit voltage is controlled by the disc thickness in the FIG. 4 configuration and the overall impedance of the piezoelectric generator is controlled by the number of discs. Many of the design considerations of a piezoelectric stack are covered in detail in U.S. Pat. No. 4,011,474.
In the operation of the apparatus described above, the drill string 12 including the subassembly 17 and bit 16 are caused to rotate through the earth formations 14 to drill to a desired depth. As drilling progresses, various loads and shocks, including those of a vibrational nature, are passed along the drill string, tending to emanate primarily upwardly from the bit through the bottom sub 80 of body 50. These forces are thus transmitted to the main body portion 70 which will be forced upwardly with respect to mandrel 40. In any event whether such forces originate from above or below the sub 17, the relative forces on the sub will cause the mandrel 40 and body 50 to telescope into an alternating open and closed configuration. By means of opposed load transmitting surface 57 on the main body portion 70; and surface 58 of split ring 47, associated with mandrel 40, the longitudinal and/or rotational forces on the drill string will compress absorber element 110 and/or piezoelectric stack 111 to dampen such forces and at the same time generate electrical energy caused by deformation of the elements 81 in the piezoelectric stack 111. At the same time, the required longitudinal loads and rotational forces, necessary to the drilling operation, are transmitted through the sub 17 to the drill bit 16 by means of the engagement of splines 45 on mandrel 40 with interior grooves 53 on drive sub 60. In the embodiment of FIG. 3 involving helical or coarse multiple lead threads, such transfer of drilling forces is accommodated by splines 43 and grooves 42 respectively.
The electrical output of the piezoelectric stack 111 is passed by means of conductors 88 to sub 18 where the output is modified appropriately to be useful in the using electrical device or circuit. For example, the output can be rectified to change the sinusoidal nature of the direct output of the piezoelectric elements 18 into a direct current. This output may also be filtered and regulated, to further refine and stabilize its form for subsequent use in electrical devices.
While particular embodiments of the present invention have been shown and described, it is apparent that changes and modifications may be made without departing from this invention in its broader aspects and it is therefore the aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of this invention. | In a drilling operation fatique producing vibrational motion is produced in the drill string in the form of longitudinal and torsional load variations at the drill bit and throughout the bottom hole assembly. These load variations occur at least partially as a result of the irregularly shaped hole bottom which develops beneath the bit and which in turn cause the bit to rise and fall with rotation, and the bit loading to vary. In addition, the rotating drill string causes gyrations in the drill string which are transmitted to the bottom end of the drill string and drill bit in the form of load and torque variations. These variations in loading appear as longitudinal and torsional vibrations in the drill string. A dampening and shock absorbing mechanism is at least partially comprised of piezoelectric elements which are responsive to the vibrations of the drill string to produce electrical energy which is used to operate downhole electrical circuits. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to a PET industrial yarn melt direct spinning manufacturing method and its device, specifically belonging to the technical field of PET industrial yarn manufacturing.
[0003] 2. Description of Related Art
[0004] Currently, PET industrial yarn manufacturing implements a chip spinning process where PTA and EG are submitted to esterification, pre-polycondensation, final-polycondensation and quenching, and then cut into chips having intrinsic viscosity of 0.63˜0.68 dL/g. The chips are further processed through solid-state polycondensation so as to produce high-viscosity chips of 0.85˜1.05 dL/g. The high-viscosity chips are put into a screw extruder for melt spinning Finally, after drawing performed by heat rollers of multiple stages, the yarn is wound for formation. As mentioned herein, solid-state polycondensation refers to a process where polyester chips are submitted to polycondensation at a temperature that is 30° C. ˜60° C. lower than the melting point thereof in a vacuum environment or in inert atmosphere such as that of nitrogen, so as to make the polyester's molecular weight continuously increase. The process of polycondensation can take as long as 20 some hours. The existing process for manufacturing PET industrial yarn through solid-state polycondensation chip spinning has problems such as long production cycles, large facility investment, and high energy consumption. Hence, liquid tackifyingmelt direct spinning manufacturing has been a desire in the industry
[0005] Though there is technical breakthrough about liquid tackifying of polyester, two more technical problems have to be solved before large-scale melt direct spinning manufacturing of PET industrial yarn becomes possible. The first one is transportation of high-viscosity melt. PET industrial yarn requires melt having intrinsic viscosity of 0.90˜1.05 dL/g or even higher. Such high-viscosity melt has great kinematic viscosity, so it is necessary to properly arrange the piping transportation of the melt from liquid tackifying reactors to spinning boxes in order to prevent excessive viscosity drop and inconsistency.
[0006] The second problem is how to make the manufacturing flexible enough for multiple PET industrial yarns. For manufacturers, it is important to make melt direct spinning PET industrial yarns in a way that provides scale merit of polyester manufacturing and satisfies the market demand for multiple PET industrial yarns.
SUMMARY OF THE INVENTION
[0007] For solving the transportation problem of melt with high viscosity in a way that provides scale merit of polyester manufacturing and satisfies the market demand for multiple PET industrial yarns, the present invention discloses a PET industrial yarn melt direct spinning manufacturing method that is flexible and intensive, and also discloses a device using this method. The technical schemes implemented are described particularly as follows.
[0008] A PET industrial yarn melt direct spinning manufacturing device comprises:
[0000] a polymerizer using a high-capacity continuous polymerizing apparatus and used for preparing base polyester melt that is polyethylene terephthalate (PET) melt having intrinsic viscosity of 0.63˜0.68 dL/g;
2 to 10 liquid tackifying reactors each connected with the high-capacity continuous polymerizing apparatus through a split-flow pipeline, wherein the base polyester melt after tackified by the liquid tackifying reactor has the intrinsic viscosity reaching 0.90˜1.10 dL/g;
multi-head spinning units in a number ranging between 2 and 10 connected with each said liquid tackifying reactor, wherein each of the spinning units is connected with the corresponding liquid tackifying reactor through a melt pipeline and equipped with 2 to 4 spinning boxes.
[0009] The device further has the following configuration.
[0000] The high-capacity continuous polymerizing apparatus refers to a polyester reactor that has single-line capacity high enough to continuously supply material for multiple liquid tackifying reactors for esterification and polycondensation.
[0010] The liquid tackifying reactor is a vertical reactor with capacity of 30˜120 ton/day.
[0011] The spinning units are located below the liquid tackifying reactor and evenly distributed to center around the liquid tackifying reactor.
[0012] The spinning units are evenly distributed around a discharge gate of the liquid tackifying reactor, and all the melt pipelines between the spinning boxes and the discharge gate of the liquid tackifying reactor have an identical length of transportation.
[0013] The melt pipeline between the spinning unit and a discharge gate of the liquid tackifying reactor has a length of transportation not exceeding 15m and has a diameter of 25˜100 mm.
[0014] The spinning units and the liquid tackifying reactor are arranged into a “linear”, “asteroidal” or “symmetrically rectangular” pattern.
[0015] A PET industrial yarn melt direct spinning manufacturing method comprises the following steps:
[0000] (1) preparing base polyester melt: performing esterification and melt polycondensation on terephthalic acid and ethylene glycol in a high-capacity continuous polymerizing apparatus, so as to produce PET (polyethylene terephthalate) base polyester melt having intrinsic viscosity of 0.63˜0.68 dL/g, wherein parameters used include:
molar ratio between ethylene glycol and terephthalic acid of 1˜1.3; for esterification, temperature of 250˜265° C., pressure of 0.12˜0.18 Mpa, and time 3˜5 hours; for pre-polycondensation, temperature of 265˜275° C., pressure of 2500˜3000 Pa, and time of 1˜1.5 hours; and for polycondensation,
temperature of 275˜295° C., pressure of 50˜150 Pa, and time of 1.5˜2.5 hours;
(2) liquid tackifying: transporting the prepared base polyester melt to liquid tackifying reactors through split-flow pipelines respectively for polycondensation, so as to produce high-viscosity polyester melt having intrinsic viscosity of 0.90˜1.10 dL/g, wherein:
the liquid tackifying reactor is a vertical reactor, and parameters used for liquid tackifying include: temperature of 270˜285° C., pressure of 50˜130 Pa, time of 40˜90 min, so that the tackified intrinsic viscosity reaches 0.90˜1.1 dL/g, melt hue (b value) smaller than 4, and terminal carboxyl group content smaller than 30 mol/t;
(3) multi-head spinning: transporting the tackified high viscosity polyester melt to the spinning units through the melt pipelines respectively for multi-head spinning that is intensive spinning with 16˜24 heads, and submitting the high viscosity polyester melt to a process of metering using a metering pump, filtering, spinning at spinnerets, quenching through chimneys, clustering and oiling, drawing and setting, and interlacing and winding formation, thereby completing spinning.
[0016] The method further has the following limitation. The base polyester melt has intrinsic viscosity of 0.63˜0.68 dL/g, with deviation less than ±0.005 dL/g, and has terminal carboxyl group content smaller than 30 mol/t.
[0017] The high-viscosity polyester melt has intrinsic viscosity reaching 0.90˜1.1 dL/g, with melt hue (b value) smaller than 4 and terminal carboxyl group content smaller than 30 mol/t.
[0018] For transporting the high-viscosity polyester melt to the spinning boxes, the pipeline is no longer than 15 m, with diameter of 25˜100 mm, temperature of 290˜298° C., pressure of 25˜30 MPa, shear rate of 10˜18 m/s, retention time no longer than 8.0 min, and viscosity drop within 0.04˜0.08 dL/g.
[0019] For the multi-head spinning, each said spinning unit spins 16˜24 strands of yarn, namely each said spinning unit having 2 spinning boxes, and each said spinning box having 4˜6 spinning members. The spinning member is of a twin-cavity cup type and has two melt passages. Two melting cavities of the spinning member each have an independent melt-filter, and two streams of the melt for the two heads share a common spinneret that has a split structure. Each said spinning member spins two strands of yarn with spinning temperature of 290˜305° C., total denier count of each spinning position up to 20040 dtex, total draw ratio of 5.6˜6.2%, oil pick-up percentage of 0.4˜1.05%. For satisfying the need for multi-head spinning with small pitch and high capacity, said winding is performed using a parallel twin take-up machine running with winding speed of 2600˜3300 m/min.
[0020] The present invention has the following benefits:
[0000] The present invention adopts a flexible, one-head-multi-reactor-multi-tail manufacturing line and intensive melt direct spinning multi-head spinning.
[0021] 1. Flexible, one-head-multi-reactor-multi-tail manufacturing line: a large-scale continuous polymerizing apparatus is used to prepare base melt for benefiting from its efficient energy use and material use and consistent melt quality due to mass manufacturing. The liquid tackifying reactor has manufacturing capacity of a proper range of 30˜120 ton/day. A polymerizing apparatus is downstream connected with 2 or more liquid tackifying reactors. Each of the liquid tackifying reactors supplies material to 2˜10 spinning units. Each of the spinning units is equipped with 2˜4 spinning boxes for spinning. Such configuration provides the benefits of batch polycondensation and is flexible enough to adapt to multiple PET industrial yarns as the market demands. Functional materials can be in-site added into the high-viscosity melt pipeline upstream the spinning system so as to produce various functional PET industrial yarns.
[0022] 2. Intensive melt direct spinning multi-head spinning since the liquid tackifying reactors have proper manufacturing capability, and the spinning process involves intensive spinning with 16˜24 heads, the spinning system following each of the liquid tackifying reactor can have a compact layout where the length of the high-viscosity melt pipeline is limited to 15 m. This compact layout when working with reasonable piping parameter and transportation conditions helps to minimize the viscosity drop. The present invention is highly adaptive to market demand of various PET industrial yarns, and significantly increase spinning capacity. It also helps to significantly reduce investment per unit capacity and energy consumption during manufacturing.
[0023] The invention as well as a preferred mode of use, further objectives and advantages thereof will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS:
[0024] FIG. 1 is a schematic diagram illustrating a flexible manufacturing method according to the present invention involving melt polymerization, liquid tackifying, and melt direct spinning;
[0025] FIG. 2 according to one embodiment of the present invention shows one arrangement of melt pipelines and spinning units for a device composed of one liquid tackifying reactor and two spinning units;
[0026] FIG. 3 according to one embodiment of the present invention shows one arrangement of melt pipelines and spinning units for a device composed of one liquid tackifying reactor and three spinning units;
[0027] FIG. 4 according to one embodiment of the present invention shows one arrangement of melt pipelines and spinning units for a device composed of one liquid tackifying reactor and four spinning units;
[0028] in FIG. 2-FIG . 4 : an elliptic figure denoting a liquid tackifying reactor 20 , an arrow denoting a melt pipeline 50 , a rectangular figure denoting a spinning unit 30 , and a rounded rectangle denoting a spinning box 60 .
DETAILED DESCRIPTION OF THE INVENTION
[0029] Referring to FIG. 1 through FIG. 4 , according to the present invention, a PET industrial yarn melt direct spinning manufacturing device comprises a polymerizer 10 , liquid tackifying reactors 20 and spinning units 30 .
[0030] The polymerizer 10 uses a high-capacity continuous polymerizing apparatus and is used for preparing base polyester melt that is polyethylene terephthalate (PET) melt having intrinsic viscosity of 0.63˜0.68 dL/g.
[0000] Two to ten liquid tackifying reactors 20 are each connected with one said high-capacity continuous polymerizing apparatus through a split-flow pipeline 40 . The base polyester melt after tackified by the liquid tackifying reactor 20 has the intrinsic viscosity reaching 0.90˜1.10 dL/g. The liquid tackifying reactor is preferably a vertical reactor having capacity of 30 to 120 ton/day.
[0031] Two to ten multi-head spinning units 30 are connected with each said liquid tackifying reactor 20 . The spinning unit 30 is connected with the corresponding liquid tackifying reactor 20 through a melt pipeline 50 and equipped with 2 to 4 spinning boxes 60 .
[0032] For achieving high efficiency of melt transportation and providing flexible and intensive production, the spinning units 30 are located below the liquid tackifying reactor 20 and evenly distributed to center around the liquid tackifying reactor 20 . Particularly, the spinning units are evenly distributed around a discharge gate of the liquid tackifying reactor, and all the melt pipelines between the spinning boxes and the discharge gate of the liquid tackifying reactor have an identical length of transportation.
[0033] As proven by experiments, the best transportation efficiency is achieved when the length of the melt pipeline between the spinning unit and the discharge gate of the liquid tackifying reactor is not exceeding 15 m and the diameter of the melt pipeline ranges between 25 and 100 mm. Under these conditions, the melt transported can maintain desirable viscosity and consistency and the transportation speed is good.
[0034] The spinning units and the liquid tackifying reactors may be arranged into a “linear” pattern as shown in FIG. 2 , into an “asteroidal” pattern as FIG. 3 , or into a “symmetrically rectangular” pattern as shown in FIG. 4 . In any of these cases, preferable results can be achieved.
[0035] The following manufacturing examples are provided for further describing the disclosed manufacturing device and the disclosed manufacturing method.
Manufacturing Embodiment 1
[0036] A polymerization device having annual capacity of 50,000 tons is selected to work with two liquid tackifying reactors. Each said liquid tackifying reactor corresponds to two spinning units. Each said spinning unit corresponds to 2-4 spinning positions. The arrangement between the liquid tackifying reactor and the spinning units as well as the design of the melt pipelines are shown in FIG. 3. The specific technical parameters used include:
[0037] (1) Liquid tackifying:
[0000] Low-viscosity polyester melt with intrinsic viscosity of 0.63˜0.68 dl/g is prepared using melt polycondensation and then pressurized by a booster pump and filtered by a filter before transported to tops of the vertical liquid tackifying reactors. The melt in the vertical liquid tackifying reactor falls naturally as an even film by gravity. Such a liquid tackifying process is conducted under temperature of 270˜285° C. and pressure of 50˜130Pa for 40˜90 minutes. After tackified, the melt has its intrinsic viscosity reaching 0.90˜1.1 dL/g, with melt hue (b value) smaller than 4 and terminal carboxyl group content smaller than 30 mol/t.
[0038] (2) Transportation of high-viscosity melt
[0000] During melt transportation, the length of transportation through the pipeline between the discharge gate of the liquid tackifying reactor and each said spinning box is identical and not exceeding 15m. Such pipeline is conducted using pipes having diameter of 25˜100 mm, with temperature of 280˜298° C., pressure of 25˜30 MPa, and shear rate of 10˜18 m/s, for retention time not exceeding 8.0 min, so as to control viscosity drop within 0.10 dL/g. The layout of the melt pipelines is as shown in FIG. 2 .
[0039] (3) Multi-head spinning
[0000] For the arrangement where one liquid tackifying reactor works for two spinning units, each said spinning unit may have 2-4 spinning positions. 16-24 heads of spinning may be achieved at each said spinning position. The total denier count at a spinning position is up to 20040 dtex. The high-viscosity polyester melt after the liquid tackifying process is transported to the spinning boxes at all the spinning positions and held at 290˜300° C. in the spinning boxes. The melt is then measured by a metering pump and filtered and comes out from the spinneret before quenched in the annealing area, clustered and oiled. For the metering pump, the pre- and post-pump pressures are 5˜8 MPa and 15˜20 MPa, respectively. The fineness of the filter is 15˜20 μm. In the annealing area, the temperature is 310˜350° C. For quenching, the air velocity is 0.3˜0.6 m/s, with temperature of 60˜80° C. and moisture of 70%˜80%. Oiling is performed at a site 30˜100 mm below the spinning chimney using two oil nozzles that draw oil form 2 oil pumps simultaneously. The oil pump is 0.05˜0.10 CC and has 1 oil inlet and 16 oil outlets, with oil pick-up percentage of 0.4˜1.05%.
[0040] (4) Drawing and heat setting:
[0000] This step is performed using a heat setting process including two stages of drawing and one stage of relaxation. The first pair of spinning rollers runs at 400˜600 m/min, with total draw ratio of 5.6˜6.2%.
[0041] (5) Winding formation:
[0000] The set fiber is input into an interlacing process for winding formation. Therein, the interlacer pressure is 0.3˜0.4 Mpa. Winding is achieved using a twin-type take-up machine, with winding speed of 2600˜3300 m/min, winding tension of 170˜230 cN, winding angle of 6.5°˜7.5°.
Manufacturing Embodiment 2
[0042] A polymerization device having annual capacity of 100,000 tons is selected to work with three liquid tackifying reactors. Each said liquid tackifying reactor corresponds to two spinning units. Each said spinning unit corresponds to 2-4 spinning positions. The arrangement between the liquid tackifying reactor and the spinning units as well as the design of the melt pipelines are shown in FIG. 4. The specific technical parameters used include:
[0043] (1) Liquid tackifying:
[0000] Low-viscosity polyester melt with intrinsic viscosity of 0.63˜0.68 dl/g is prepared using melt polycondensation and then pressurized by a booster pump and filtered by a filter before transported to tops of the vertical liquid tackifying reactors. The melt in the vertical liquid tackifying reactor falls naturally as an even film by gravity. Such a liquid tackifying process is conducted under temperature of 270˜285° C. and pressure of 50˜130 Pa for 40˜90 minutes. After tackified, the melt has its intrinsic viscosity reaching 0.90˜1.1 dL/g, with melt hue (b value) smaller than 4 and terminal carboxyl group content smaller than 30 mol/t.
[0044] (2) Transportation of high-viscosity melt
[0000] During melt transportation, the length of transportation through the pipeline between the discharge gate of the liquid tackifying reactor and each said spinning box is identical and not exceeding 15 m. Such pipeline is conducted using pipes having diameter of 25˜100 mm, with temperature of 280˜298° C., pressure of 25˜30 MPa, and shear rate of 10˜18 m/s, for retention time not exceeding 4.6˜7.0 min, so as to control viscosity drop within 0.10 dL/g. The layout of the melt pipelines is as shown in FIG. 3 .
[0045] (3) Multi-head spinning
[0000] For the arrangement where one liquid tackifying reactor works for two spinning units, each said spinning unit may have 2-4 spinning positions. 16-24 heads of spinning may be achieved at each said spinning position. The total denier count at a spinning position is up to 20040 dtex. The high-viscosity polyester melt after the liquid tackifying process is transported to the spinning boxes at all the spinning positions and held at 290˜300° C. in the spinning boxes. The melt is then measured by a metering pump and filtered and comes out from the spinneret before quenched in the annealing area, clustered and oiled. For the metering pump, the pre- and post-pump pressures are 5˜8 MPa and 15˜20 MPa, respectively. The fineness of the filter is 15˜20 μm. In the annealing area, the temperature is 310˜350° C. For quenching, the air velocity is 0.3˜0.6 m/s, with temperature of 60˜80° C. and moisture of 70%˜80%. Oiling is performed at a site 30˜100 mm below the spinning chimney using two oil nozzles that draw oil form 2 oil pumps simultaneously. The oil pump is 0.05˜0.10 CC and has 1 oil inlet and 16 oil outlets, with oil pick-up percentage of 0.4˜1.05%.
[0046] (4) Drawing and heat setting:
[0000] This step is performed using a heat setting process including two stages of drawing and one stage of relaxation. The first pair of spinning rollers runs at 400˜600 m/min, with total draw ratio of 5.6˜6.2%.
[0047] (5) Winding formation:
[0000] The set fiber is input into an interlacing process for winding formation. Therein, the interlacer pressure is 0.3˜0.4 Mpa. Winding is achieved using a twin-type take-up machine, with winding speed of 2600˜3300 m/min, winding tension of 170˜230 cN, winding angle of 6.5°˜7.5°.
Manufacturing Embodiment 3
[0048] A polymerization device having annual capacity of 200,000 tons is selected to work with four liquid tackifying reactors. Each said liquid tackifying reactor corresponds to two spinning units. Each said spinning unit corresponds to 2-4 spinning positions. The arrangement between the liquid tackifying reactor and the spinning units as well as the design of the melt pipelines are shown in FIG. 5 . The specific technical parameters used include:
[0049] (1) Liquid tackifying:
[0000] Low-viscosity polyester melt with intrinsic viscosity of 0.63˜0.68 dl/g is prepared using melt polycondensation and then pressurized by a booster pump and filtered by a filter before transported to tops of the vertical liquid tackifying reactors. The melt in the vertical liquid tackifying reactor falls naturally as an even film by gravity. Such a liquid tackifying process is conducted under temperature of 270˜285° C. and pressure of 50˜130 Pa for 40˜90 minutes. After tackified, the melt has its intrinsic viscosity reaching 0.90˜1.1 dL/g, with melt hue (b value) smaller than 4 and terminal carboxyl group content smaller than 30 mol/t.
[0050] (2) Transportation of high-viscosity melt
[0000] During melt transportation, the length of transportation through the pipeline between the discharge gate of the liquid tackifying reactor and each said spinning box is identical and not exceeding 15 m. Such pipeline is conducted using pipes having diameter of 25˜100 mm, with temperature of 280˜298° C., pressure of 25˜30 MPa, and shear rate of 10˜18 m/s, for retention time not exceeding 4.6˜7.0 min, so as to control viscosity drop within 0.10 dL/g. The layout of the melt pipelines is as shown in FIG. 4 .
[0051] (3) Multi-head spinning
[0000] For the arrangement where one liquid tackifying reactor works for two spinning units, each said spinning unit may have 2-4 spinning positions. 16-24 heads of spinning may be achieved at each said spinning position. The total denier count at a spinning position is up to 20040 dtex. The high-viscosity polyester melt after the liquid tackifying process is transported to the spinning boxes at all the spinning positions and held at 290˜300° C. in the spinning boxes. The melt is then measured by a metering pump and filtered and comes out from the spinneret before quenched in the annealing area, clustered and oiled. For the metering pump, the pre- and post-pump pressures are 5˜8 MPa and 15˜20 MPa, respectively. The fineness of the filter is 15˜20 μm. In the annealing area, the temperature is 310˜350° C. For quenching, the air velocity is 0.3˜0.6 m/s, with temperature of 60˜80° C. and moisture of 70%˜80%. Oiling is performed at a site 30˜100 mm below the spinning chimney using two oil nozzles that draw oil form 2 oil pumps simultaneously. The oil pump is 0.05˜0.10 CC and has 1 oil inlet and 16 oil outlets, with oil pick-up percentage of 0.4˜1.05%.
[0052] (4) Drawing and heat setting:
[0000] This step is performed using a heat setting process including two stages of drawing and one stage of relaxation. The first pair of spinning rollers runs at 400˜600m/min, with total draw ratio of 5.6˜6.2%.
[0053] (5) Winding formation:
[0000] The set fiber is input into an interlacing process for winding formation. Therein, the interlacer pressure is 0.3˜0.4 Mpa. Winding is achieved using a twin-type take-up machine, with winding speed of 2600˜3300 m/min, winding tension of 170˜230 cN, winding angle of 6.5°˜7.5°. | A PET industrial yarn melt direct spinning manufacturing method and a device thereof are disclosed. The device includes a polymerizer preparing base polyester melt, liquid tackifying reactors, and multi-head spinning units. The liquid tackifying reactors are connected with the polymerizer through split-flow pipelines respectively and after tackified by the tackifying reactors, the base polyester melt has its intrinsic viscosity reaching 0.90-1.10 dL/g. Each of the liquid tackifying reactors is connected with spinning units, and the spinning units are connected to the liquid tackifying reactors through melt pipelines. Each of the spinning units is provided with spinning boxes. The device solves the transportation problem of melt with high viscosity, combines both scale efficiency of the condensation production and market demand of multiple PET industrial yarns, and has the characteristic of integrating flexible production and intensive production. | 3 |
BACKGROUND OF THE INVENTION
The field of the invention relates generally to removable head attachments for mounting on ends of temporary support poles at a construction or remodeling job site, and more specifically to a head attachment and pole assembly for securing a flexible partition material to erect temporary walls or partitions on a job site.
It is known to provide one or more temporary support poles having removable head attachments on construction and remodeling job sites. The poles and head attachments may serve a variety of purposes such as holding drywall in place for installation, holding cabinets in place for installation, and assembling temporary walls or partitions to control and contain dust accumulation, among other things, on a construction site. Such temporary walls may be assembled, for example, to isolate finished areas from work areas within an existing structure so that the finished areas will not be contaminated by construction dust and by-products. The temporary walls are fabricated from a flexible partition material, such as sheet or curtain materials, that is draped and held in place with the temporary support poles.
BRIEF DESCRIPTION OF THE INVENTION
An embodiment of a head attachment for a temporary support pole is disclosed. The head attachment includes a body having a generally planar upper surface and a lower surface opposing the upper surface, and a pivotally movable retainer element coupled to the body and selectively positionable relative to the upper surface between an open position and a closed position. The pivotal retainer element has an upper side and a lower side opposing the upper side. The upper side of the retainer element is generally parallel with the upper surface of the body when the retainer is in the closed position.
Optionally, the upper side of the retainer element may be recessed from the upper surface of the body when in the closed position. The retainer element may be hingedly attached to the body. The upper surface of the body may define a rim extending around the retainer element. The rim may be U-shaped, and at least one recessed surface may extend adjacent the rim. A gasket may also be applied to the rim, and the gasket may be U-shaped.
The retainer element may also be nested in the upper side of the body when in the closed position, and the retainer element may pivot upwardly and outwardly away from the engagement surface when moved from the closed position to the opened position. The retainer element may also include a latching element. The latching element may include a pointed distal end. The body may include a front side and a rear side opposing the front side, with the front side including a slot, and the distal end of the latching element being received in the slot when the latching element is closed. The retainer element may include an upper surface, and the latching element may be recessed relative to the upper surface of the retainer element.
The body may also include an external side, and the retainer element may be attached to the body along the external side. At least one aperture may be formed in the body, with the aperture providing access to the retainer element so that the retainer element can be raised from the closed position. The head attachment may also include an attachment portion configured for threaded engagement with the support pole. The head attachment may also include a flange configured for connection to the temporary support pole and at least one rib supporting the flange. The rib may have a bowed curvature imparting a variable thickness along an axial length thereof.
An embodiment of a support pole assembly for erecting a temporary partition on a job site with at least one support pole section is also disclosed. The assembly includes a head attachment mountable to the support pole section on one end; the head attachment comprising a body and a retainer element hingedly attached to the body. The retainer element is movable upwardly and outwardly away from a first portion of the body to an open position for draping a flexible partition material over a second portion of the body and a closed position capturing the partition material between the retainer element and the first portion of the body.
Optionally, the head attachment is mountable to the support pole section with threaded engagement. The head attachment may include an upper side formed as a U-shaped rim, the U-shaped rim extending around the retainer element. The head attachment may also include a rear surface that is recessed from the rim. The retainer element may be recessed from the rim when the retainer is in the closed position.
As another option, the head attachment may include an upper side defining a rim, and a gasket applied to at least a portion of the rim. The gasket may be U-shaped.
The retainer element may further include a latching element. The latching element may be configured to pierce the partition material. The partition material may be a curtain. A flange may be provided that is configured for connection to the at least one support pole section. At least one rib may be provided to support the flange. The rib may have a bowed curvature imparting a variable thickness along an axial length thereof.
An embodiment of a support pole assembly for erecting a temporary wall with a curtain on a job site has also been disclosed. The assembly includes: at least one support pole section having a threaded member; a head attachment configured to engage the threaded member, the head attachment defining a recess; and a retainer element hingedly attached to the head surface proximate the recess, the retainer element movable upwardly and outwardly away from the recess to an open position for draping the curtain over a portion of the head attachment and a closed position capturing a portion of the curtain in the recess.
Optionally, the head attachment may define an upper side for engagement with the curtain, and the retainer may be substantially parallel with the upper side when in the closed position. The retainer may also be recessed from the upper side when in the closed position. The head attachment may include a latching element. The threaded element may be one of a threaded stud and an adaptor configured for coupling with a threaded stud.
As further options, the head assembly may also include a flange configured to engage the threaded member, and at least one rib supporting the flange. The rib may include a bowed curvature imparting a variable thickness along an axial length thereof. A gasket may extend on an upper surface of the head attachment, and the gasket may be U-shaped.
BRIEF DESCRIPTION OF THE DRAWINGS
Non-limiting and non-exhaustive embodiments are described with reference to the following Figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
FIG. 1 is a partial top perspective view of a support pole assembly having a head attachment formed in accordance with a first exemplary embodiment of the invention and having a curtain retainer in a closed and unlatched position.
FIG. 2 is a bottom perspective view of the head attachment shown in FIG. 1 .
FIG. 3 is a top perspective view of the head attachment shown in FIGS. 1 and 2 with the curtain retainer in an opened position.
FIG. 4 is a top view of the retainer shown in FIGS. 1-3 with the curtain retainer closed and a latching element in an unlatched position.
FIG. 5 is view similar to FIG. 4 but showing the latching element in a latched position and, in combination with the curtain retainer, securing a curtain material to the head attachment.
FIG. 6 is a partial rear elevational view of the support pole assembly shown in FIG. 1 being engaged to a ceiling on a job site.
FIG. 7 illustrates in front perspective view a plurality of support pole assemblies supporting a temporary partition on the job site.
FIG. 8 is a top perspective view of a head attachment for a support pole assembly formed in accordance with a second exemplary embodiment of the invention.
FIG. 9 is a bottom perspective view of the head attachment shown in FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a partial top perspective view of a support pole assembly 100 for erecting a temporary wall or partition on a job site wherein, for example, construction or remodeling activity is being undertaken.
The support pole assembly 100 generally includes, as shown in FIG. 1 , a support pole 102 including a coupler 104 , and a head attachment 106 that is removably attachable from the support pole 102 via the coupler 104 .
The pole 102 is fabricated from known materials in one or more sections having a generally elongated axial length measured along a longitudinal axis 103 and may be adjustable in length as those in the art will appreciate to accommodate different floor-to-ceiling heights, for example, in use. The pole 102 may be preassembled with multiple sections or may include multiple threaded pole sections that may be assembled on the job site. In a multiple pole section embodiment, the overall length of the combined pole sections may be adjustable, for example, by twisting or sliding one pole section relative to the other to advance the ends of the pole sections toward or away from one another in a telescoping manner, and locking the pole sections in place to maintain a desired axial length of the pole 102 . While fabrication of the pole 102 in sections is beneficial for the reasons stated, it is contemplated that the pole 102 in different embodiments may be a single section elongated pole having a fixed length.
The coupler 104 is attached to the distal end of the pole 102 and in the example shown includes threads with which the head attachment 106 may be securely mated. In one contemplated embodiment, the coupler 104 is provided as an adapter that is fitted with a threaded stud 105 provided on the end of the pole 102 . In such an embodiment, the coupler 104 includes internal threads having a smaller diameter engaging the smaller diameter stud 105 of the pole 102 , and external threads having a larger diameter for engagement with the head attachment 106 . By providing such an adaptor as the coupler 104 , the pole 102 may be used with other attachments and for other purposes that do not require the coupler 104 .
In another embodiment, however, the coupler 104 having the appropriate diameter of threads for coupling with the head attachment 106 , may itself be provided on the distal end of the pole in lieu of the stud 105 . In such an embodiment, the head attachment may be directly attached to the larger diameter coupler 104 without using any type of adapter.
In still another embodiment, the pole coupler 104 and the stud 105 could be configured so that they could each be used interchangeably with the pole 102 . As such, the terminal stud 105 could be removed from the distal end of the pole 102 and replaced with the coupler 104 , or the coupler 104 could be removed from the distal end of the pole 102 and replaced with the stud 105 . Various other adaptations are possible.
Regardless, in the example shown the threaded engagement of the head attachment 106 and the coupler 104 provides a fixed and rigid structural connection between the pole 102 and the head attachment 106 . Once the head attachment 106 is engaged to the threaded coupler 104 , the orientation of the head attachment 106 relative to the pole 102 is not adjustable. In other words, and because of the threaded engagement, the head attachment cannot pivot or tilt relative to pole axis 103 at the end of the pole 102 to change the working angle of the head attachment 106 as it engages a ceiling. In other embodiments, however, it is understood that non-threaded couplers could be used that may allow for pivotal or tilted adjustment of the working angle if desired, including but not limited to ball and socket-type coupling techniques familiar to those in the art.
The head attachment 100 generally includes a rectangular body 108 having an upper side or surface 110 and a lower side or surface 112 opposing the upper side 110 . The body 108 is provided with a curtain retainer element 114 on the upper side 108 and with a cylindrical attachment flange 116 , sometimes referred to as a stem, on the lower side 112 . The curtain retainer 114 secures a curtain material (not shown in FIG. 1 ) to the attachment head 106 , while the flange 116 mates with the coupler 104 on the pole 102 and secures the head attachment 106 to the pole 102 .
The body 108 in the exemplary configuration shown includes a front side 118 , a rear side 120 opposing the front side 118 , and opposing lateral sides 122 , 124 interconnecting the front at rear sides 118 , 120 . The sides 118 , 120 , 122 , 124 extend generally parallel to the longitudinal axis 103 of the pole 102 , are about the same length, and generally impart a square shape to the body 108 . The sides 118 , 120 , 122 , 124 also include rounded corners at their ends where the sides meet one another. Other shapes and geometric configurations of the body 108 are, of course, possible in various other embodiments, including but not limited to rectangular shapes having sides of unequal length, other non-rectangular polygonal shapes, and non-polygonal shapes such as circles or ellipses.
The top side or upper side 110 of the body 108 as shown is generally planar and extends in a generally U-shaped configuration as shown in FIG. 1 . The upper side 110 extends in a plane generally perpendicular to the axis 103 of the pole 102 and generally perpendicular to the front side 118 , the rear side 120 , and the opposing lateral sides 122 , 124 . The upper side 110 in the example shown defines an elongated rim surface extending adjacent the entire front side 118 , and most of the lateral sides 122 , 124 . In the example shown, however, the upper side 110 does not extend along the rear side 120 of the body 108 .
The rear side 120 of the body 108 is formed with a central opening or cutout 126 , and recessed upper surfaces 128 extend between the opening 126 and to the respective lateral sides 122 and 124 . As shown in FIG. 3 , a second recessed surface 130 is formed on the inner periphery of the upper side 110 . The second recessed surface 130 accommodates the curtain retainer 114 such that a top surface 132 of the retainer 114 is recessed from the upper side 110 , and the upper side 110 generally extends around the retainer 114 . When the retainer 114 is in the closed position as shown in FIG. 1 , the upper side surface 110 is elevated from the rear side surfaces 128 and also the top surface 132 of the retainer element 114 in the exemplary embodiment shown. Also, the top surface 132 of the retainer element 114 is generally planar, and in the closed position the retainer top surface 132 is oriented generally parallel to, but spaced from, the plane of the upper side 110 .
The retainer element 114 , as best seen in FIGS. 1 and 3 , is shaped generally complementary to the upper side 110 of the body 108 but at a reduced dimension such that the retainer element 114 is inset in the upper side 110 when the retainer element is in the closed position shown in FIG. 1 . Thus, the retainer element in the illustrated example is generally square in shape and includes the upper side 132 , a lower side 134 ( FIG. 33 ) opposing the upper side 132 , a front edge 136 , a rear edge 138 and lateral side edges 140 and 142 .
The curtain retainer 114 is formed with a pair of hinge arms 144 , 146 extending from the rear edge 138 . The hinge arms 144 , 146 extend to the opening 126 in the rear wall 120 of the body 108 , and the hinge arms 144 , 146 are rotatably attached to the rear side 120 of the body 108 at end walls 145 , 147 ( FIG. 3 ). In contemplated embodiments, one of the end walls 145 , 147 and the hinge arms 144 , 146 are provided with hinge pegs that are received and rotated in apertures formed in the other of the end walls 145 , 147 and the hinge arms 144 , 146 . Other hinge arrangements are possible, however, allowing the curtain retainer 114 to be moved between a closed position ( FIG. 1 ) nested within the body upper side 110 , and an opened position ( FIG. 3 ) creating a receptacle for securing a portion of curtain material between the body 108 and the retainer 114 .
As shown in FIGS. 2 and 3 , apertures 148 , 150 are provided in the body 108 at a location interior to the upper side 110 for one's fingers to push the retainer 114 open from the lower side 134 for rotation about the hinges as shown. Because the retainer 114 is nested in the upper side 110 when in the closed position, it is difficult to open the retainer 114 from the top side of the head attachment 104 , so by accessing the retainer 114 from underneath via the apertures 148 , 150 , the retainer 114 may be relatively easily raised until it can be grasped from the top side and rotated to the opened position.
The retainer element 114 is further provided with a latch element 150 that is movable in a recessed slot 152 formed in the upper side 132 of the retainer 114 . The slot 152 and/or the latching element 152 may be formed with guiding an alignment features to provide a slidable motion of the latch element 152 along a linear path in a direction toward or way from the body front side 118 as explained below. As also shown in FIGS. 5 and 6 , the latch element includes a pointed, triangular leading end 154 that may pierce or penetrate a portion of a curtain material 200 ( FIG. 4 ) that is secured to the head attachment 106 with the retainer 114 . The latch element 152 is generally slidably positionable with a person's thumb, for example, between an unlatched position ( FIG. 4 ) and a latched position ( FIG. 5 ) wherein the leading end 154 of the latch penetrates the curtain material 200 . The combination of the closed retainer element 114 and the latching of the latching element 150 securely holds the curtain material in place. As such, the head attachment 106 does not rely solely upon frictional forces to retain the curtain material.
In the unlatched position, the leading end 154 of the latching element 152 is spaced from the front side 118 and the upper side 110 , and hence does not interfere with or prevent the retainer 114 from being opened. In the latched position, however, the leading end 154 of the latching element 152 extends partly into a slot 160 formed in the front side 160 ( FIG. 1 ) of the body 108 beneath the upper side 110 . The extension of the end 154 of the latching element 152 into the slot 160 locks the retainer 114 closed and precludes an inadvertent opening of the retainer 114 , as well as prevents the retainer 114 from being opened, without first moving the latch element 152 to the unlatched position. Furthermore, in the latched position, the retainer 114 is prevented from inadvertent opening as the head attachment 106 is handled. Thus, positive latching or unlatching of the retainer 114 both enhances the retention of the curtain material and protects the retainer 114 from being inadvertently damaged.
While an exemplary latching element 152 is described, it is recognized that other latching elements are known in the art and may be utilized to retain the door 114 in a closed position and/or to provide further securement of the curtain material in another manner. For example only, magnetic latching features could be utilized in other embodiments.
The lower side 112 of the head attachment 106 includes the generally cylindrical flange 116 as shown in FIG. 2 approximately centered in the body 108 and extending outwardly in a direction perpendicular to the lower side 112 . The flange 116 includes internal threads for mating engagement with the threaded coupler 104 . The head attachment 106 may therefore be quickly and easily mounted to and removed from the pole 102 by threading the flange 116 to the coupler 104 by hand and without tools.
As mentioned above, while threaded engagement of the coupler 104 and the head attachment 106 is shown in the exemplary embodiment depicted, other types of engagement are possible and may be utilized. For example, ball and socket-type connections are known in the art and may alternatively be utilized, as well as other known socket and coupler arrangements, or other fastening methods whether or not involving a socket, may alternatively be utilized in other embodiments with similar effect to removably couple the head attachment 106 to the pole section 102 .
The head attachment 106 , including the body 108 , the retainer 114 and the latching element 152 may be fabricated from durable molded plastic materials according to known techniques in an exemplary embodiment, although other materials may also be utilized if desired.
By virtue of the hinged connection and the aperture 126 at the rear side 120 of the body 108 , the retainer element 114 may pivot or swing upwardly and outwardly away from the upper side 110 of the body 108 from the closed position ( FIGS. 1 and 4 ) to the open position ( FIG. 3 ) and even beyond. In one embodiment, the front side 144 of the retainer element may travel a substantially 270° arcuate path from a fully closed to a fully opened position as the pivot arms 144 , 146 are rotated about the hinged connection with the rear side 120 at the end walls 145 , 147 . That is, the retainer element 114 opens and closes in a door-like manner away from and toward the body 108 . The retainer element 114 is therefore sometimes referred to as a retaining door.
When fully opened, the retainer door 114 beneficially provides clear and unobstructed access to fit the curtain material 200 ( FIG. 4 ) over the upper side 310 of the body 108 . When the retainer 114 is closed with the curtain material in place, the curtain material is trapped between the lower side 134 of the retainer door 114 and the recessed surface 130 ( FIG. 3 ) of the receptacle. The latching element 152 may then be moved to the latched position as shown in FIG. 4 . By penetrating the curtain material as the latching element 152 is latched, further mechanical retention of the curtain material is provided. As seen in FIG. 4 , the curtain material 200 is draped over the upper side 110 , but does not extend over the recessed rear surfaces 128 of the body 108 . In other words, the edge of the curtain material is generally aligned with the inner edge of the surface 128 at the rear side 120 but does not cover the surface 128 . Otherwise, the curtain material 200 would generally interfere with closing of the retainer 114 .
FIGS. 6 and 7 illustrate the curtain material 200 utilized to erect a temporary wall with the curtain material 200 . Curtain material 200 is shown mounted to a plurality of poles 102 via the head attachments 106 . As shown in FIGS. 6 and 7 , as the head attachment engages a ceiling 302 of a room 300 the curtain material 200 is draped from the head attachments 106 and generally extends from the floor 304 to the ceiling 302 and between adjacent poles 102 . The curtain material 200 overlies the upper side 110 of the head attachment 106 , and the curtain material makes direct contact with the ceiling as the head attachment 106 approaches the ceiling 302 .
As can be seen from FIG. 6 , however, the surfaces 128 of the rear side 120 of the head attachment body 108 are recessed from the upper side 110 of the head attachment 106 and also recessed from the curtain material draped over the top of the upper side 110 . As such, the surfaces 128 of the rear side 120 are spaced from the ceiling when the curtain material 200 is in contact with the ceiling 302 . The upper side 132 of the curtain retainer 114 is also recessed from the upper side 110 and the curtain material 200 that covers the upper side 110 , so the retainer 114 is also spaced from the ceiling when the curtain material 200 is in contact with the ceiling 302 . Only the curtain material 200 is actually in contact with the ceiling 302 as the head attachment 106 is used, and because of the shape of the upper side 110 , a relatively small, but effective, contact area between the curtain material 200 and the ceiling 302 is created. This arrangement tends to protect the ceiling from damage when using the poles, provides some protection to the retainer 114 from being inadvertently damaged as the poles are used, and provides some protection for the hinged connection of the retainer 114 at the rear side 120 of the head attachment 106 . The hinged connection of the retainer 114 is mechanically isolated from compression forces when the head attachment 106 is engaged with the ceiling.
A temporary partition or wall with the curtain material 200 may be created between opposing walls 306 and 308 of the room 300 to separate one portion of the room from another as shown in FIG. 7 . As such, a portion of the room 300 on one side of the partition may be isolated from the portion of the room 300 on the other side to contain construction dust, debris, etc. in the portion of the room wherein work is being undertaken. As such, a finished area of the room 300 may be protected or preserved in a clean condition while work is undertaken in another portion of the room 300 . When work is completed, the poles 100 and the partition material 200 are removed from the site.
Many configurations of such temporary partitions are possible involving different numbers of poles, different lengths of poles, and different partition materials such as plastic sheets, fabrics, cloths, drapes, tarps, and the like familiar to those in the art. Such partitions may be assembled to extend between adjacent walls in a room, opposing walls in a room, or to partition an area in a room that is not bordered by an existing wall of the room. Openings may be provided, if necessary in the partitions to allow workers to enter or leave partitioned areas.
FIGS. 8 and 9 are top and bottom perspective views of a second exemplary embodiment of a head attachment 400 that may be utilized in the support pole assembly described above in lieu of the head attachment 106 described above.
Like the head attachment 106 , the head attachment 400 similarly includes a body 108 that in the exemplary configuration shown includes a front side 118 , a rear side 120 opposing the front side 118 , and opposing lateral sides 122 , 124 interconnecting the front at rear sides 118 , 120 . The sides 118 , 120 , 122 , 124 generally impart a square shape to the body 108 . The sides 118 , 120 , 122 , 124 also include rounded corners at their ends where the sides meet one another. As noted previously, other shapes and geometric configurations of the body 108 are possible in various other embodiments, including but not limited to rectangular shapes having sides of unequal length, other non-rectangular polygonal shapes, and non-polygonal shapes such as circles or ellipses.
Also like the head attachment 106 , the top side or upper side 110 of the body 108 of the head attachment 400 as shown is generally planar and extends in a plane generally perpendicular to the axis of the pole (such as the axis 103 of the pole 102 shown in FIG. 1 ) and generally perpendicular to the front side 118 , the rear side 120 , and the opposing lateral sides 122 , 124 . Unlike the head attachment 106 , the upper side 110 of the head attachment 400 in the example shown defines an elongated rim surface extending adjacent the entire front side 118 , the entirety of each of the lateral sides 122 , 124 and a portion of the rear side 120 .
A gasket 402 is applied to the upper side 110 of the head attachment 400 , and in the exemplary embodiment shown, the gasket 402 includes a non-slip upper surface that is elevated from the upper side. The gasket 402 further extends in a U-shaped configuration extending on the upper surface 110 entirely across the front side 118 , most of the lateral sides 122 , 124 , but not across the rear side 120 . As such, the rear side 120 has an upper surface that is recessed from the upper surface of the gasket 402 . As such, when the upper surface of the gasket 402 is engaged to a ceiling or other object in use, the upper surface of the rear side 120 does not engage the ceiling or other object.
As shown in FIG. 9 , the head attachment also includes a plurality of solid support ribs 404 extending about the cylindrical attachment flange 116 , sometimes referred to as a stem, on the lower side 112 . The support ribs 404 connect to the flange 116 at one end, and extend to the rounded corners of the lower side 112 at their opposing ends. As such, and in the example shown, the ribs 404 extend diametrically across the lower side 112 of the head attachment 400 . The ribs 404 as shown further include a bowed or arcuate curvature along their axial lengths, such that the ribs 404 are thicker near the flange 116 than at their ends adjacent the corners of the lower side 112 . The ribs 404 provide additional structural strength and rigidity to the head attachment 400 to better withstand manufacturing processes and rugged use in the field. While four ribs 404 are shown, greater or fewer numbers of ribs having the same or different configuration may alternatively be provided for similar purposes.
The curtain retainer 114 is constructed, installed, and operable in a similar manner for the head attachment 400 as described above for the head attachment 406 , with similar benefits and advantages.
The above-described head attachments and pole assemblies are believed to be particularly advantageous and beneficial over existing head attachments and pole assemblies. The retainer elements described are believed to be easier to use than some conventionally provided retainers, and also are believed to be more durable and may be manufactured at lower cost. The described head attachments and retainers are believed to be particularly advantageous for securing partition materials to the temporary support pole sections, but it is contemplated that other materials, items, and articles may likewise be reliably secured to the head attachments for purposes other than erecting temporary partitions. As such, the invention is not believed to be solely limited in application to securing flexible partition materials. The benefits of the invention are believed to be equally applicable to non-partition applications and the present disclosure is not intended to preclude such possibilities.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. | A temporary support pole assembly including removable head attachment is disclosed. The head attachment includes a pivotally movable retainer selectively positionable relative to the head between an open position and a closed position to retain and secure a flexible partition material thereto. | 4 |
RELATED APPLICATIONS
This application claims priority to Provisional Application No. 60/460,183, filed Apr. 3, 2003, the entirety of which is hereby incorporated by reference.
This application is also related to the following patents and pending applications, each of which is hereby incorporated herein by reference in its entirety:
U.S. Pat. No. 6,418,478, titled PIPELINED HIGH SPEED DATA TRANSFER MECHANISM, issued Jul. 9, 2002, Application Ser. No. 09/610,738, titled MODULAR BACKUP AND RETRIEVAL SYSTEM USED IN CONJUNCTION WITH A STORAGE AREA NETWORK, filed Jul. 6, 2000, Application Ser. No. 09/744,268, titled LOGICAL VIEW AND ACCESS TO PHYSICAL STORAGE IN MODULAR DATA AND STORAGE MANAGEMENT SYSTEM, filed Jan. 30, 2001, Application Ser. No. 60/409,183, titled DYNAMIC STORAGE DEVICE POOLING IN A COMPUTER SYSTEM, filed Sep. 9, 2002, Application Ser. No. 60/460,234, titled SYSTEM AND METHOD FOR PERFORMING STORAGE OPERATIONS IN A STORAGE NETWORK, filed Apr. 4, 2003,
COPYRIGHT NOTICE
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 disclosures, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
The invention disclosed herein relates generally to performing storage operations through a firewall. More particularly, the present invention relates to providing a limited number of ports in a firewall for performing secure storage operations between components in a computer network.
Firewalls reside between components in a computer network and generally function to prevent unauthorized access to the network by evaluating which communications should be allowed to pass between the firewall's network and other networks or network components. A firewall thus divides a network into two parts: a friendly/secure side and a hostile side, wherein computers inside the firewall on the friendly side are protected from computers outside the firewall on the hostile side.
A firewall evaluates whether network traffic such as data streams, control messages, application data, communications packets, and other data meets specified security criteria and should be allowed to pass between components of the network. Data that does not meet the security criteria is generally discarded or otherwise blocked from passing between components. A firewall may comprise hardware elements, software components, or any combination thereof. Exemplary firewalls include packet filters, bastion hosts, application or circuit-level gateways, and proxy servers.
One method used by firewalls to prevent unauthorized communications is to restrict network communications to specified ports. A port is generally used by TCP/IP. UDP, and other communication protocols to represent the logical endpoint of a particular connection. For example, HTTP traffic associated with a particular computer might be routed through port 80 . Various programs, services, and other applications on a computer often run listening processes for network traffic directed to a particular port. Limiting network communications to specific ports and closing all unused ports generally reduces the risk of unauthorized access to a computer since these programs, services, and other applications could be compromised or otherwise exploited by a hacker to gain access to the computer.
Firewalls provide additional security by timing out network sessions beyond a specified time period. Thus, ports do not remain unnecessarily open in the event of network connection failures, slowdowns, or other events which might create vulnerabilities. For example, any network sessions that become idle beyond a preconfigured timeout period are automatically disconnected without warning. Further, after making a new connection, a first packet must be sent within a timeout period or the connection is also disconnected.
Existing storage management systems, however, use many thousands of ports to conduct storage operations through a firewall. Typically, these systems keep large sets of known ports open during backups and restores. Each of the streams of data sent as part of a backup, a restore, or other storage operation must have a port open in the firewall to pass the data. For example, data pieces come through multiple streams, control signals come through other streams, status messages come yet other streams, etc. The head end (sender) and tail end (receiver) of existing systems, however, do not know which ports all of the data is coming through, so they generally reserve large blocks of ports in the firewall to accommodate the various streams of data that they anticipate. Furthermore, these systems also must keep many ports open since slow network connections and other factors may cause a connection to timeout and the firewall to close an intended port thus requiring data to be resent to another port. Opening thousands of ports in this manner, however, renders a firewall more like a switch than a firewall and severely compromises network security.
There is thus a need for systems and methods which reduce the number of open ports required in a firewall to perform storage operations in a computer network.
SUMMARY OF THE INVENTION
In some embodiments, the present invention provides systems and methods for performing storage operations through a firewall.
In one embodiment, the invention provides a method for performing storage operations through a firewall in a networked computer system, including identifying, based on configuration data, whether each of a set of network elements is within a trusted network or not within the trusted network. Traffic between elements within the trusted network and elements not within the trusted network must pass through the firewall. The method further includes, prior to performing a storage operation through the firewall, allocating a specific set of ports, in accordance with at least one security parameter, for use in performing the storage operation.
In another embodiment, the invention provides a method for performing storage operations through a firewall in a networked computer system, including identifying, based on configuration data, a first set of network elements which are within a trusted network and a second set of network elements which are not within the trusted network. Traffic between elements within the trusted network and elements not within the trusted network must pass through the firewall. The invention further includes, prior to performing a storage operation through the firewall, allocating a specific set of ports, according to at least one security parameter, for use in performing the storage operation. The method further includes, during the storage operation, monitoring traffic through each of the specific ports. The method further includes, if, through the monitoring, traffic is determined to be inactive through a first port of the specific ports for a specified time period, sending a packet through the first port.
In another embodiment, the invention provides a system for performing storage operations through a firewall in a networked computer system. The system includes a firewall and a plurality of network elements, including one or more client computers and one or more storage devices. The system further includes a storage manager. The system further includes one or more media agents which conduct data between the one or more client computers and the one or more storage devices under the direction of the storage manager. The storage manager identifies, based on configuration data, a first set of network elements which are within a trusted network and a second set of network elements which are not within the trusted network. Traffic between elements of the trusted network and elements not within the trusted network must pass through the firewall. Further, the storage manager, prior to performing a storage operation through the firewall, allocates a specific set of ports, according to at least one security parameter, for use in performing the storage operation. During a storage operation, the firewall opens ports in accordance with the allocation.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated in the figures of the accompanying drawings which are meant to be exemplary and not limiting, in which like references are intended to refer to like or corresponding parts, and in which:
FIG. 1 is a block diagram of a network architecture for a system to perform storage operations through a firewall according to an embodiment of the invention; and
FIG. 2 is a flow diagram of a method of performing storage operations through a firewall according to an embodiment of the invention.
DETAILED DESCRIPTION
With reference to FIG. 1 embodiments of the invention are presented. FIG. 1 presents a block diagram of a network architecture for a system to perform storage operations on electronic data in a computer network according to an embodiment of the invention. As shown, the system includes a storage manager 115 and one or more of the following: a data agent 100 , a client 105 , an information store 110 , an index cache 120 , a firewall 125 , a media agent 130 , and a storage device 135 . The system and elements thereof are exemplary of a three-tier backup system such as the CommVault Galaxy backup system, available from CommVault Systems, Inc. of Oceanport, N.J., and further described in application Ser. No. 09/610,738 which is incorporated herein by reference in its entirety.
A data agent 100 is generally a software module that is generally responsible for archiving, migrating, and recovering data of a client computer 105 stored in an information store 110 or other memory location. Each client computer 105 has at least one data agent 100 and the system can support many client computers 107 . The system provides a plurality of data agents 100 each of which is intended to backup, migrate, and recover data associated with a different application. For example, different individual data agents 100 may be designed to handle Microsoft Exchange data, Lotus Notes data, Microsoft Windows 2000 file system data, Microsoft Active Directory Objects data, and other types of data known in the art.
If a client computer 105 has two or more types of data, one data agent 100 is generally required for each data type to archive, migrate, and restore the client computer 105 data. For example, to backup, migrate, and restore all of the data on a Microsoft Exchange 2000 server, the client computer 105 would use one Microsoft Exchange 2000 Mailbox data agent 100 to backup the Exchange 2000 mailboxes, one Microsoft Exchange 2000 Database data agent 100 to backup the Exchange 2000 databases, one Microsoft Exchange 2000 Public Folder data agent 100 to backup the Exchange 2000 Public Folders, and one Microsoft Windows 2000 File System data agent 100 to backup the client computer's 105 file system. These data agents 100 would be treated as four separate data agents 100 by the system even though they reside on the same client computer 105 .
The storage manager 115 is generally a software module or application that coordinates and controls the system. The storage manager 115 communicates with all elements of the system including data agents 100 , client computers 105 , firewalls 125 , media agents 130 , and storage devices 135 , to initiate and manage system backups, migrations, and recoveries, as well as perform other storage-related operations.
A media agent 130 is generally a media management software module that conducts data, as directed by the storage manager 115 , between the client computer 105 and one or more storage devices 135 such as a tape library, a magnetic media storage device, an optical media storage device, or other storage device. The media agent 130 is communicatively coupled with and controls the storage device 135 . For example, the media agent 130 might instruct the storage device 135 to use a robotic arm or other means to load or eject a media cartridge, and to archive, migrate, or restore application specific data. The media agent 130 generally communicates with the storage device 135 via a local bus such as a SCSI adaptor. In some embodiments, the storage device 135 is communicatively coupled to the data agent 130 via a Storage Area Network (“SAN”).
Each media agent 130 maintain an index cache 120 which generally stores index data the system generates during backup, migration, and restore storage operations as further described herein. For example, storage operations for Microsoft Exchange data generate index data such as file names, file locations, media identifiers, and other information. Index data provides the system with an efficient mechanism for locating user files for recovery operations. This index data is generally stored with the data backed up to the storage device 135 , and the media agent 130 that controls the storage operation also writes an additional copy of the index data to its index cache 120 . The data in the media agent 130 index cache 120 is thus readily available to the system for use in storage operations and other activities without having to be first retrieved from the storage device 135 .
The storage manager 115 also maintains an index cache 120 . Index data is also used to indicate logical associations between components of the system, user preferences, management tasks, network pathways, data associations, storage policies, user preferences, and other useful data. For example, the storage manager 115 might use its index cache 120 to track logical associations between media agents 130 and storage devices 135 .
Index caches 120 typically reside on their corresponding storage component's hard disk or other fixed storage device. Like any cache, the index cache 120 has finite capacity and the amount of index data that can be maintained directly corresponds to the size of that portion of the disk that is allocated to the index cache 120 . In one embodiment, the system manages the index cache 120 on a least recently used (“LRU”) basis as known in the art. When the capacity of the index cache 120 is reached, the system overwrites those files in the index cache 120 that have been least recently accessed with the new index data. In some embodiments, before data in the index cache 120 is overwritten, the data is copied to an index cache 120 copy in a storage device 135 . If a recovery operation requires data that is no longer stored in the index cache 120 , such as in the case of a cache miss, the system recovers the index data from the index cache 120 copy stored in the storage device 135 .
As previously discussed, firewalls 125 reside between components of the system and generally function to prevent unauthorized access to the system. Thus, for example, a firewall 125 may reside between a client 105 and the storage manager 125 , between the storage manager 125 and a media agent 130 , or between other system components. For example, a remote client 105 across the Internet or other wide area network may pass traffic associated with storage operations and other operations to the system via a firewall 125 . As another example, the system may perform remote storage operations, such as remote disaster recovery operations or other operations, and pass traffic associated with storage operations from the storage manager 125 across the Internet or other wide area network to a remote media agent 130 . These examples are not intended to be limiting and other useful configurations will be readily apparent to those skilled in the art.
In some embodiments, components of the system may reside and execute on the same computer. In some embodiments, a client computer 105 component such as a data agent 100 , a media agent 130 , or a storage manager 115 coordinates and directs local archiving, migration, and retrieval application functions as further described in application Ser. No. 09/610,738. This client computer 105 component can function independently or together with other similar client computer 105 components.
The system increases security of storage operations through a firewall 125 by, among other things, drastically reducing the number of ports required as compared to existing storage management systems. The system negotiates a limited number of ports in advance, so that only certain pre-established ports need be open to storage operation traffic. The system also provides a built-in timeout value which is less than the firewall 125 timeout value to eliminate firewall 125 timeouts requiring further renegotiation to open another port.
A port configuration file specifying the ports to open for each system computer is stored in the index cache 120 or other memory of each machine. In some embodiments, the storage manager 115 index cache 120 also contains a master list of all open ports for all computers in the system which can be accessed by and distributed to other machines in the system as necessary. For example, a port configuration file may specify that only ports 8600 to ports 8620 should be opened for use by the system. System hardware and software modules will thus only listen to those ports and all other available ports will remain closed unless requested by some other application, service, process, etc.
The system reserves and also limits the number of ports used by each system component such as the storage manager 115 , data agents 100 , and media agents 130 . In one embodiment, port limitations are based on the minimal number of ports required to conduct storage operations.
For example, the storage manager 115 is allocated seven ports. Three ports carry control data such as start and stop messages, control checksums, parity blocks, and other control data. Three additional ports serve as reserve ports and may be used to support traffic overflow or additional control signals. The final port is used to conduct traffic associated with a graphical user interface (“GUI”). For example, in some embodiments, users at client computers 105 can remotely access the storage manager 115 control GUI and other GUI interfaces. The final port is used to carry signals associated with remote access to the GUI. As another example, the final port also carries signals associated with a user at the storage manager 115 remotely accessing GUIs at clients 115 and media agents 130 . Media agents 115 and data agents 100 are allocated two ports each: one port sends data upstream from the component to the storage manager 115 and one port receives data sent downstream from the storage manager 115 to the component. In some embodiments, media agents 115 and data agents 100 are allocated two additional ports to communicate upstream and downstream with other media agents 115 or data agents 100 . Additional pairs of ports can be allocated to media agents 115 and data agents 100 to provide increased bandwidth, such as for additional backup streams or restore streams.
A “hostile computer” configuration file specifying a list of “hostile” computers is also stored in the index cache 120 or other memory of each machine. In some embodiments, the storage manager 115 index cache 120 also contains a master list of all “hostile” computers in the system which can be accessed by and distributed to other machines in the system as necessary. In some embodiments, a “friendly computer” configuration file specifying a list of “friendly computers is used instead of or concurrently with a “hostile computer” configuration file.
This second configuration file enables, among other thing, the system to determine which computers should pass traffic through the listed firewall 125 ports in the port configuration file and which computers are exempt from passing traffic through the firewall 125 . For example, computers behind the firewall 125 can pass traffic through any ports since they are within the “trusted” network and thus their network traffic does not need to be evaluated by the firewall 125 . Conversely, when one computer is behind the firewall 125 and one computer is not, then traffic between those computers must pass through the firewall 125 via the ports specified in the ports configuration file.
According to one embodiment of the invention, the “hostile computer” configuration file specifying the list of “hostile” computers lists all computers which are on the other side or “hostile” side of the firewall 125 from the computer on which the second configuration file is stored. Traffic with computers not on the list (e.g.—“friendly” computers) is routed directly, however, traffic with computers on the list (e.g.—“hostile” computers) is routed through the firewall 125 . Thus if the storage manager 115 and a media agent 130 are on the “friendly” side of the firewall 125 and a data agent 100 is on the “hostile” side, the storage manager 125 and the media agent 130 configuration files would each list the data agent 100 , and the data agent 100 configuration file would list both the storage manager 125 and the media agent 130 . Computers identified on the second configuration file list are identified according to a network address, an IP address, a DNS entry, a UNC pathway, or other network identifier known in the art.
At startup, system components, such as data agents 100 , data agents 130 , and the storage manager 115 access their ports configuration files and the “hostile computer” configuration files. Data is thus routed through ports in the firewall 125 as appropriate and according to security parameters set forth in the configuration files.
The system also stores a “keep alive” value or key in the index cache 120 or other memory of each machine. The “keep alive” value is generally a value that is less than the connection timeout value specified in the firewall 125 configuration files. The system uses the “keep alive” value, among other things, to prevent the firewall 125 from timing out connections or otherwise closing ports due to network connection failures, slowdowns, or other events which might create vulnerabilities. The system tracks the time period that a connection between a system component, as a data agent 100 , and a firewall 125 has remained idle. If the connection remains idle for a period of time equal or greater than the “keep alive” value, then the system sends a “dummy” packet or other similar packet to the firewall 125 to refresh the connection and restart the timer on the firewall connection timeout value.
In some embodiments, it may be necessary or desirable that chunk creation time be less than a firewall time-out interval, to prevent firewall time-out from occurring. Therefore, if chunk creation time is greater than the firewall time-out interval, then chunk size may be reduced, such as by the storage manager, as necessary to reduce chunk creation time to less than that of the firewall time-out interval.
FIG. 2 presents a flow diagram of a method of performing storage operations through a firewall according to an embodiment of the invention. The system accesses configuration data, step 200 . For example, in some embodiments, the system loads a configuration file specifying system components as hostile or trusted. The system checks the status of a component, step 205 . If a system component is trusted, then traffic is permitted without having to pass through the firewall, step 210 . For example, trusted components inside the firewall may not be required to pass traffic through the firewall. If a component is not trusted, the system allocates one or more specified ports to that component according to security preferences, step 215 . The system monitors ports allocated to components, step 220 , and determines whether a time period, for example a firewall timeout setting, has been exceeded, step 225 . In some embodiments, the system monitors to determine whether traffic has passed through an allocated port within the time period. If the time period has not been exceeded, control returns to step 220 and the system continues to monitor traffic. Otherwise, if the time period has been exceeded, the system sends a packet, such as a dummy packet to prevent a port closing, through the port, step 230 , and control returns to step 220 .
Systems and modules described herein may comprise software, firmware, hardware, or any combination(s) of software, firmware, or hardware suitable for the purposes described herein. Software and other modules may reside on servers, workstations, personal computers, computerized tablets, PDAs, and other devices suitable for the purposes described herein. Software and other modules may be accessible via local memory, via a network, via a browser or other application in an ASP context, or via other means suitable for the purposes described herein. Data structures described herein may comprise computer files, variables, programming arrays, programming structures, or any electronic information storage schemes or methods, or any combinations thereof, suitable for the purposes described herein. User interface elements described herein may comprise elements from graphical user interfaces, command line interfaces, and other interfaces suitable for the purposes described herein. Screenshots presented and described herein can be displayed differently as known in the art to input, access, change, manipulate, modify, alter, and work with information.
While the invention has been described and illustrated in connection with preferred embodiments, many variations and modifications as will be evident to those skilled in this art may be made without departing from the spirit and scope of the invention, and the invention is thus not to be limited to the precise details of methodology or construction set forth above as such variations and modification are intended to be included within the scope of the invention. | The present invention provides systems and methods for performing storage operations through a firewall. Methods are provided that include, in a networked computer system, identifying, based on configuration data, whether each of a set of network elements is within a trusted network or not within the trusted network. Traffic between elements within the trusted network and elements not within the trusted network must pass through a firewall. The methods also include, prior to performing a storage operation through the firewall, allocating a specific set of ports, in accordance with at least one security parameter, for use in performing the storage operation. Methods are also provided which include monitoring traffic through the specific ports, and, if traffic is determined to be inactive through a first port of the specific ports, sending a packet through the first port. | 7 |
SUMMARY
This invention is designed to eliminate waste, and spillage of salad dressing, gravy and other essentially liquid or creamy type condiments and foods, yet allow passage of chunky type dressings such as blue cheese dressing or tarter sauce. It is an object of this invention to minimize waste and spillage thus enhancing sanitary conditions in public eating places such as restaurants and fast food establishments. It is further an object of this invention to provide a means of controlling the amount of condiments discharged in each operation of the invention. It is a further object of this invention that it be electrically operated thus freeing one's hands for holding food trays or plates. An additional object of this invention is that the invention be easy to assemble and dissassemble for ease of cleaning and sanitizing. Another object of the invention is to provide a means whereby the condiments are protected from dirt, dust, flying glass, flies, human contamination, and the condiments container can easily be removed and refrigerated for longer time of preserving the condiments before use.
DESCRIPTION OF PRIOR ART
1. Field of the Invention
This invention relates to dispensing apparatus; and more particularly to a device for dispensing a predetermined quantity of liquids or semi-liquid foods, soups, dressings, and condiments.
2. Description of Prior Art
This invention is an improvement over, and is directly related to CHRONIS, U.S. Pat. No. 4,232,801. CHRONIS was a complicated hand operated device. The present invention replaces complicated gearing and spring mechanisms with cams, cam followers, and an electric drive mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view with a cutaway of the invention.
FIG. 2 is a diagram of the electrical circuitry.
FIG. 3 is a isometric of the manual mode of operation.
FIG. 4 is an isometric of a dispensing door which slides vertically.
FIG. 5 is an isometric view of another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1 the invention has a chassis 1, a start button 2, piston 3, a slide valve 4, a dispensing door 5, and a motor 6 having a drive shaft 7. The chassis 1 may be made of metal or rigid plastic and may be machined from a solid block or it may be built up; however, for simplicity of description it will be described as machined from a solid block. The chassis 1 has a top 8, a bottom 9, a dispensing end 10, a butt end 11, and two sides 12. Machined into the top 8 of the chassis 1 is an essentially rectangular, shallow opening designated a valve chamber 13. The valve chamber 13 has a lip 14 which retains therein the slide valve 4, said slide valve 4 being sized in width and depth to slideably operate in the valve chamber 13. Toward the rear of the invention, the butt end 11 is hollowed out, forming a wall 50 towards the rear of the valve chamber 13. Between the wall 50 and the slide valve 4 is a cushion 51. The cushion 51, shown as a spring, may be any resilient material and shape so long as it acts as a decelerator and cushions any impact the slide valve 4 may impart to the wall 50. Through the rear of the valve chamber 13 towards the butt end 11, there is drilled a slide valve push arm hole 15. Affixed to the rear of the slide valve 4 is a round slide valve push arm 16 which passes through the slide valve push arm hole 15. The slide valve 4 is generally flat but has a beveled front edge, so that it looks and acts like a knife valve.
In the chassis 1, from the dispensing end 10 toward the butt end 11, is bored a round piston chamber 17. The piston 3 is generally cylindrical and sized to operate slideably within the piston chamber 17. Affixed to the rear of the piston 3 is a piston rod 18. A sufficiently tight seal may be achieved between the piston 3 and the piston chamber 17, usually by close machine tolerances; however the well known practice of rings or seals is obvious, and contemplated in attaining a suitable slide fit.
The dispensing end 10 is machined to accomodate a dispensing door 5. In this description a sliding dispensing door 5 is shown, having a dove tail edge configuration, mating with the dispensing end 10. The dispensing door 5 is shown to travel horizontally, but vertical movement is obvious as shown in FIG. 4; as well as a hinged door not shown. Further, while the piston chamber 3 is shown to exit the dispensing end 10, it is also obvious that the piston chamber 3 could exit on the sides 12 or downward, as a design choice and the dispensing door 5 could be oriented to close any of the selections of orientation of the piston chamber 17.
Connecting the valve chamber 13 and the piston chamber 17 is a feed port 20. A flat top plate 21 is sized to fit and seal the valve chamber 13. A supply port 22 in the top plate 21 provides a support, seal, and access passage for condiment to the valve chamber 13. Condiment is stored in suitable containers 23, refrigerated, thermos, heated or otherwise, said containers 23 mating in any standard manner with the supply port 22. The top plate 21 may be secured to the chassis 1, as by screws 52.
Mounted in or near the bottom 9 is the motor 6. The motor 6 is shown to be an electric motor whose energy source, not shown, is any convenient suitably powered electrical outlet. Rising vertically from the motor 6 is the drive shaft 7. Mounted on the drive shaft 7, are a plurality of cams. The drive shaft 7 passes through a shaft hole 24 in a divider wall 25. The divider wall 25 and the shaft hole 24 provide a moisture seal for the electric motor 6 area by means of a shaft seal 26 mounted in the shaft hole 24 and said shaft seal 26 forming a seal on the drive shaft 7.
Rigidly mounted on the drive shaft 7 is a slide valve cam 27. A slide valve cam follower 28, which is biased against the slide valve cam 27 by means of a slide valve cam spring 29, rides against the slide valve cam 27, and the slide valve cam follower 28 is rigidly connected to vertically mounted slide valve axle 30. The slide valve cam spring 29 is connected to the slide valve cam follower 28 and to the chassis 1. The slide valve axle 30 is pivotally mounted in the chassis 1. Rigidly attached to the slide valve axle 30, near the top of the slide valve axle 30, is a slide valve actuating arm 31. The slide valve actuating arm 31 is pivotally connected to the slide valve push arm 16. Thus, the slide valve cam follower 28 imparts an oscillatory rotating motion to the slide valve axle 30, which inturn imparts an oscillatory motion to the extended slide valve actuating arm 31, and thus a reciprocating motion to the slide valve 3 causing the slide valve to alternately open then close the supply port 22.
Rigidly mounted on the drive shaft 7 adjacent to the slide valve cam 27 is a dispensing door cam 32. A dispensing door cam follower 33, which is biased against the dispensing door cam 32 by means of a dispensing door cam spring 34, rides against the dispensing door cam 32, and the dispensing door cam follower 33 is rigidly connected to a vertically mounted dispensing door axle 35. The dispensing door cam spring 34 is connected to the dispensing door cam 33 and to the chassis 1. The dispensing door axle 35 is pivotally mounted in the chassis 1. As shown, the dispensing door axle 35 is mounted coaxially with and inside of the slide valve axle 30, and the two axles 30 and 35 are separated from each other by bearings, not shown. Rigidly attached to the dispensing door axle 35, near the top of the dispensing door axle 35, is the dispensing door actuator arm 36. The dispensing door actuator arm 36 is pivotally connected to the dispensing door 5. Thus, the dispensing door cam follower 33 imparts an oscillatory rotary motion to the dispensing door axle 35, which in turn imparts an oscillatory motion to the extended dispensing door actuator arm 36, which in turn imparts a reciprocating motion to the dispensing door 5.
It has been found that because some condiments may have particles which tend to jam a sliding type door, that additional biasing of the dispensing door 5 toward its closed position is desirable. Therefore, the door biasing spring 37 is connected between the dispensing door actuator arm 36 and the chassis 1.
Rigidly mounted at the top of the drive shaft 7 is the piston drive wheel 38. The piston drive wheel 38 has a plurality of pin holes 39 which are spaced radially from near the center of the piston drive wheel 38 to near its perimeter. Pivotally mounted to the piston drive wheel 38 in the desired pin hole 39 by means of a pin 40 is a piston actuator rod 41. The other end of the piston actuator rod 41 is pivotally connected to the extremity of the piston rod 18. Thus connected, the rotary motion of the piston drive wheel 38 is converted into reciprocating motion of the piston 3. The length of the stroke of the piston 3 is determined by which of the pin holes 39 the piston actuator rod 41 is connected; and the length of the piston 3 stroke determines the volume of condiment to be dispensed each operation of the invention.
A compartment 53 formed by a divider wall 25, the wall 50, the butt end 11, and the two sides 12 contains all the cams and the upper portion of the drive shaft 7. The compartment 53 is covered with a rear deck plate 54. The rear deck plate 54 is secured to the chassis 1 as by screws 52.
The slide valve cam 27, the dispensing door cam 32, and the piston drive wheel 38 are sized, shaped and oriented on the drive shaft 7 so that the slide valve 4, the dispensing door 5 and the piston 3 are actuated sequentially.
Electrically, the invention is shown to have a non-reversible constant speed electric motor 6, which draws electrical energy from any convenient outlet. One side of the circuit is connected directly to the motor 6. The other side of the circuit is connected to an off-switch selector 42. The off-switch selector 42 is a manually positioned switch, which selects one of two off-switches 43 to be in the circuit. The circuit then continues to the selected off-switch 43. The off-switches 43 are identical to each other and both are spring spring biased switches which have cam follower actuators. The off-switches 43 are positioned at any convenient position in the system where the desired action can be obtained. The function of the off-switches 43 is to shut off power to the electric motor 6 when the piston 3 is either in the full forward position, or in the fully retracted position. Thus the off-switches 43 can be actuated by any of the cams or actuator arms. The circuit continues from the off-switches 43, to the motor 6. Across the circuit from the motor 6 to the other side from the power source is connected a start switch 44. The start switch 44 is spring loaded to the off position. When the starter switch 44 is closed the circuit is completed and the motor 6 begins to turn, and the selected cam actuated off-switch 43 is closed. While the start switch 44 may be released to the off position, the circuit remains complete until the cam operated off-switch 43 selected is opened, shutting off the invention.
In some versions of the invention, the containers 23 may have a small electric motor driven stirrer 45 therein. The stirrer 45 is electrically connected to the main circuit with a timer delay switch 46, such that the stirrer 45 will run for a short period of time, for example four seconds, before the main motor 6 is allowed to start. It is also obvious that the stirrer 45 could be driven by the main motor 6 by a pulley arrangement, not shown, to the stirrer 45.
Some condiments may need to be heated, such as gravies; and it is obvious that a heating element 48 through a thermostat 47 could be connected to the main circuit, the heating elements 48 being inside the container 23.
The off-switches 43 are actuated to shut off the invention when either the piston 3 is in the fully dispensed, forward position, or in the fully retracted position. The two modes of operation are designed for two types of condiments. Thick condiments will take a little longer to feed into the piston chamber 17, and therefore the invention is turned off by an off-switch 43 when the piston is fully retracted, thus allowing the condiment to feed into the piston chamber 17 prior to the next usage. Very little time is needed for thin less viscous condiments to feed into the piston chamber 17 and therefore the invention is shut off by the other off-switch when the piston 3 is in the full forward, having just dispensed position.
As shown, the dispensing door 5 slides horizontally. Because the condiment may collect, and soil the area around the dispensing door 5, an alternative configuration, not shown, would be an obvious extension of the configuration which is shown, to provide the capability of having the dispensing door 5 operate vertically. The design could easily be modified by having the motor 6 and drive shaft 7 as well as the connecting cams, axles, and arms operate in in an orientation perpendicular to that shown. For example, if the drive shaft 7 and the motor 6 rotated about an axis horizontal, yet perpendicular to the line of motion of the piston 3, and the slide valve axle 30 as well as the dispensing door axle 35 were also horizontally mounted, it is easy to visualize a mechanism similar to that depicted such that the slide valve 4 and the piston 3 would operate as shown, yet the dispensing door 5 would operate vertically.
Because of possible residue build up at the dispensing end 10 it is also contemplated that the dispensing door 5 would be equipped with a wiper 49, especially in the vertically sliding dispensing door 5 configuration. The wiper 49, being rubber, or rubber-like resilient material, could be slid into a groove 61 in the dispensing door 5, and it would scrape the dispensing end 10 clean.
Again it is obvious that the valve chamber 13, slide valve 4, slide valve push arm 16, and the top plate 21 could be built as a unit removeable from the chassis 1, and disconnectable from the slide valve actuating arm, as shown in FIG. 5. The whole unit then with one of the containers 23 becomes removable; and the slide valve acts as a lid for the container 23; and the decreased likelihood of spillage, along with the ease with which the whole unit could transfered for refrigeration is desirable.
A manual mode of operation for the invention may be desireable to provide the invention with the capability of being operated when there is no available electricity. This can be accomplished by means of a disengageable gearing system 55 in conjunction with a hand crank 56. The hand crank 56 extends out through the side of the chassis 1. The disengageable gearing system 55 would be such that when the hand crank 56 is used to operate the invention, the motor 6 would be turned by the drive shaft 7, and the drive shaft 7 would be turned by the hand crank 56. This feature, as depicted in FIG. 3, is an optional addition to the basic invention. However it is realized that an unlimited number of different variations will be possible and obvious to one skilled in the art. FIG. 3 shows that when the hand crank 56 is pushed towards the drive shaft 7, a bevel gear 57 mounted on the hand crank 56 engages a mating bevel gear 58 mounted on the drive shaft 7. When the hand crank 56 is turned, the invention is operated and the motor 6 is mechanically turned. When the hand crank 56 is released, the mating bevel gear 58 is disengaged from the bevel gear 57 because the hand crank 56 is biased to disengage by a crank biasing spring 60. | An improved dressing and food dispenser, adjustable for quantity of portion dispensed, which is driven by an electric motor, and cam operated, to apportion, then dispense. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to automatic offset presses in which a series of processes from a printing process through a plate unloading process to a blanket cylinder cleaning process are automatically carried out. More particularly, the invention relates to a plate loading device, a water duct roller mechanism and a form roller mechanism in the automatic offset press.
An offset press is well known in the art in which an automatic plate loading device is provided so that an original plate is conveyed by being held between rollers and is automatically loaded onto a plate cylinder. Then, form rollers are brought into contact with the surface of the plate on a plate cylinder to coat the plate surface with printing ink and a moisture supplying solution, the ink being transferred to the image region.
In the conventional printing machine described above, for an initial period after the plate has been loaded onto the plate cylinder, the plate is not satisfactorily fitted to the plate cylinder using conventional gripper means. Accordingly, portions of the plate, other than those where it is desired to do so, are brought into portions of the plate contact with the form rollers. That is, the ink is undesirably coated onto other than the pattern region.
The portions of the plate surface undesirably coated with ink can be cleaned or the ink stains on the plate surface can be removed while the plate cylinder makes several revolutions. However, since the clearance between the plate cylinder and the rubber blanket cylinder is small, as the plate cylinder is rotated, the ink stains on the portions of the plate which are not satisfactorily fitted to the plate cylinder are brought into contact with the rubber blanket cylinder and transferred onto the cylinder. Accordingly, it is impossible to obtain a satisfactory printing result from the beginning of the printing operation. Therefore, disadvantageously, it is necessary to repeatedly carry out a test printing until a satisfactory printing result is obtained.
SUMMARY OF THE INVENTION
In view of the above-described difficulty, the invention is intended to provide an automatic printing machine with an automatic plate loading device which is so designed that, according to the invention, first the water duct roll mechanism is activated, then the form roller mechanism is operated to cause the form rollers to contact the plate cylinder. Thereafter, the plate loading device carries out the plate loading operation whereby the original plate is closely and completely fitted to the plate cylinder from the beginning thus preventing the plate surface from being contaminated. Accordingly, a satisfactory printing result is obtained with the plate loaded onto the plate cylinder beginning with the first printed sheet.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic longitudinal sectional view of a preferred embodiment of an automatic printing machine according to the invention;
FIG. 2 is a side view of a water duct roller mechanism in the automatic printing machine;
FIG. 3 is an explanatory diagram showing the operation of an operating lever in the automatic printing machine;
FIG. 4 is a front view of an operating lever positioning mechanism;
FIGS. 5 and 6 are side views of a form roller mechanism in the printing machine viewed from the operating side and the opposite side, respectively;
FIG. 7 is a side view of a plate loading device with an operating lever automatic returning device; and
FIG. 8 is a side view of the plate loading device from the opposite direction from FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of an automatic printing machine constructed according to the invention will be described with reference to the accompanying drawings.
In FIG. 1, reference numeral 9 designates an impression cylinder; 10 a water duct roller mechanism composed of a water fountain roller 11, a water duct roller 12 and a distribution roller 13; and 14 an ink duct roller mechanism composed of a fountain roller 15, a duct roller 16 and a distribution roller 17. A plurality of ink rollers 18 are arranged between the distribution roller 17 and form rollers 6 and 6'. Further in FIG. 1, reference numeral 19 designates a plate unloading device, 20 a blanket cylinder cleaning device 21, a sheet feeding device, and 22 a sheet discharging device.
Before the plate loading operation of the plate loading device 1, the water duct roller mechanism 10 is operated after which the form roller mechanism 7 is operated to cause the form rollers 6 and 6' to contact the plate cylinder 5. Thereafter, the plate loading operation is carried out.
The water duct roller mechanism 10 is operated through a cam lever 23 pivotally mounted on a frame (not shown) and a sub-lever 24 coupled to one end portion of the cam lever 23 by rotation of a cam 26 which is fixedly secured to an operating shaft 25 as shown in FIG. 2. An operating lever (described below) is fixedly secured to the operating shaft 25. A lever 29 pivotally mounted on a shaft 28 is rotatably coupled through a link 27 to the cam lever 23. A latch 31 is loosely fitted on the shaft 28 and a spring 30 is connected between the latch 31 and the lever 29 so that the latch 31 is turned as the lever 29 is turned. The engaging portion 31a of the latch 31 is freely movable into and out of engagement with the engaging portion 32a of a rotatable lever 32. Engagement and disengagement are effected as follows: When the roller 34 of the lever 32 is brought into contact with a cam 33, the rotation of the cam 33 will cause the lever 32 to pivot periodically to control the latch.
The lever 32 is coupled to a link 35 which is coupled to an arm 37 having a roller 36 thereon. The arm 37 rotatably supported on secured to the shaft 28. An arm 38 is fixedly mounted on the shaft 28 at one end and has a roller 39 at the other end. A pin 40a fixed to an arm 40 is interposed between the roller 39 and the abovedescribed roller 36 in such a manner that it can be freely moved back and forth. By controlling the amount of movement of th arm 40, the angular disposition of the arm 37 and shaft 28 can be changed thereby to change the angular position of an arm 41 (described below).
The arm 41 is fixedly secured to the shaft 28 at one end and has a pin 42 at the other end. The pin 42 is engaged with a frame 43 holding the water fountain roller 11 and the water duct roller 12. As the lever 32 is turned with rotation of the cam 33, the arm 41 is rocked to cause the water duct roller 12 to supply a suitable quantity of water to the distribution roller 13. In this connection, the position of the arm 40 is controlled to control the rocking position of the arm 41 thereby to adjust the contact time during which the water duct roller 12 is in contact with the distribution roller 13. FIG. 2 shows the water duct roller mechanism 10 in a stopped state with the roller 12 out of contact with the distribution roller 13.
The above-described cam 26 has a protrusion 26a. When the operating lever 44 is turned to the position II in FIG. 3, the sub-lever 24 is turned counterclockwise by a roller 45 pivotally mounted on the sub-lever 24 and the protrusion 26a of the cam 26 whereupon the lever 29 strikes a stop 47 by the elastic force of a spring 46 whereby the water duct roller 12 is operated. When the operating lever 44 turns the operating shaft 25 so that the roller 45 of the sub-lever 24 does not touch the cam 26, the sub-lever 24 is turned clockwise by the elastic force of the spring 48 until it abuts against the 49.
When the operating lever is returned to the position II after the printing operation, the lever 23 is turned counterclockwise through the sub-lever 24 by the cam 26 so that the operation of the water duct roller 12 is stopped.
After completion of the operation of the water duct roller mechanism 10, the form roller mechanism 7 is operated to cause the form rollers 6 and 6' to contact the plate cylinder 5 to apply the moisture supplying solution and the ink thereto.
The form roller mechanism 7 is constructed as shown in FIGS. 5 and 6. An arm 50 is fixedly secured to the abovedescribed operating shaft 25. The arm 50 is coupled through a link 51 to a cam 52 in such a manner that the cam 52 is turned as the position of the operating lever 44 is changed. The rollers 56 and 57 of arms 54 and 55, which are pivotally coupled together at 53, are abutted against the cam 52. The arms 54 and 55 are pivotally coupled to arms 58 and 59 which pivotally support the form rollers 6 and 6', respectively. The cam 52 is coupled through a link 60 to an arm 61. The arm 61 is coupled through a shaft 63 to an arm 62 (FIG. 6) on the opposite side of the plate cylinder 5. The arm 62 is coupled through a link 64 to a cam 65 which is similar to the cam 52. Similarly as in the cam 52, rollers 68 and 69 pivotally mounted on arms 66 and 67, which are pivotally coupled at 53, are abutted against the cam 65, and arms 70 and 71 pivotally support the form rollers 6 and 6', respectively. As the cams 52 and 65 rotate, the form rollers 6 and 6' are brought into and out of contact with the plate cylinder 5 by the rollers 56, 57, 68 and 69 abutting against the cams 52 and 65 as the cams rotate.
The operating lever 44 can be set in any of six positions as shown in FIG. 3. A series of printing operation steps are carried out by changing the position of the operating lever 44.
A mechanism for positioning the operating lever 44 is shown in FIG. 4. A set cam 74 having four engaging recesses 72 and one cam recess 73 is fixedly secured to the operating shaft 25 described above. An arm 75 having an engaging roller 76 at one end is pivotally mounted on the frame in such a manner that the engaging roller 76 is held engaged with one of the engaging recesses 72 of the set cam 74 by the elastic force of a spring 77. As the operating shaft 25 is turned by the operating lever 44, the set cam 74 is turned so that the engaging roller 76 engages with the engaging recesses 72 one after another to hold the operating lever 44 at the positions I, II, III, IV and V successively (FIG. 3). The recess 73 is so designed that, when the operator releases the operating lever 44 when it is at the position VI, the operating lever 44 can be automatically returned to the position V.
The various processes for printing are carried out by moving the operating lever 44 stepwise along the recesses 72. After the completion of a printing operation, the operating lever 44 is automatically returned from the position V through the positions IV, III and II to the position I. For this purpose, an automatic returning mechanism 78 is provided as shown in FIG. 7. An arm 82 is rocked through a link 81 by a crank mechanism 80 coupled to a rubber blanket cylinder shaft 79. A pawl 83 with a pin 84 is pivotally mounted on one end portion of the arm 82 in such a manner that the pawl 83 is reciprocated with the rocking motion of the arm 82. When the solenoid 89 is not activated prior to the completion of the printing, the pin 84 is rocked in the counter-clockwise direction by the edge 85a of a cam 85. As the cam is abutbed against a stop 87 by the elastic force of a spring 86, the pin 84 is maintained in the position illustrated in FIG. 7. Under this condition, the pawl 83 is disengaged from a ratchet 88 secured to operating shaft 25. When a printing completion signal is generated by a counter which performs a subtraction operation by countint sheets as they are printed, a solenoid is energized so as to turn the cam 85 through a link 90 as a result of which the pin 84 is moved downwardly to cause the pawl 83 to engage with the ratchet 88. Thus, under the condition that the pawl 83 is engaged with the ratchet 88, as the rubber blanket cylinder shaft 79 is turned, the ratchet 88, and accordingly the operating shaft 25, are turned to return the operating lever 44 stepwise.
The plate loading mechanism 1, as shown in FIGS. 7 and 8, includes cam 91, 92 and 93 secured to the operating shaft 25 and switches 94, 95 and 96 which are positioned to be operated by the cams 91, 92 and 93. A solenoid 97 is energized by the switch 95. A link 99 is coupled to the solenoid 97. The link 99 is urged in the return direction by a spring 98. A lever 101 is coupled to the link 99 in such a manner that the lever 101 which is secured to a rod 100 is rotated by the energization of the solenoid 97 thereby to operate (open and close) a switch 102.
More specifically, the lever 101 is operated as follows: When the highest point 103a of a cam 103 mounted on one side of the rubber blanket cylinder 8 abuts against a roller 105 which is pivotally supported by a rotatable arm 104 to turn the arm 104 thereby to disengage the pin 106 of the arm 104 from the engaging portion 107a of a latch 107 which is also secured to rod 100 with the elastic force of the spring 98 in association with the operation of the solenoid, the lever 101 is operated. Arm arm 109 is rockably mounted on a shaft 108 in such a manner that it is rocked by rotation of the arm 104 when the roller 105 is engaged with the low point 103b of the cam 103. An arm 110 bearing the roller 3 is fixedly mounted on the shaft 108. The arms 109 and 110 are urged to turn clockwise by a spring 111 so that the roller 3 is caused to contact the roller 4 which is driven by the drive motor. Under this condition, an original plate 2 inserted between the rollers is delivered to the plate cylinder 5.
The plate cylinder 5 has conventional plate gripping means (not shown). When a plate is loaded on the plate cylinder, a switch 113 is opened by the cam 112 fixed to the rubber blanket cylinder shaft 79. The switch 113 is fixedly mounted on a lever 115 which is turned upon energization of the solenoid 97 and returned by a spring 114. Upon closure of the switch 113, the solenoid 97 is deenergized to return the lever 115 thereby to open the switch 113. When the roller 105 comes into contact with the cam 103, the pin 106 engages the latch 107 so that the roller 3 is moved away from the roller 4 thus stopping the plate loading operation. In this operation, when the switch 102 is closed by the solenoid 97, a solenoid (not shown) for operating a gripper mechanism (not shown) is operated.
The above-described water duct roller mechansim 10, form roller mechanism 7 and plate loading device 1 are activated in association with the operating shaft 25 as follows:
When the operating lever 44 is at the position I, the neutral position as shown in FIG. 3, all mechanical operations are in a stopped state. When the operating lever 44 is shifted to the position II, the drive motor (not shown) of the printing machine is operated by the switch 94 so that water is supplied from the water duct roller 12 to the disbribution roller 13 and then from the distribution roller 13 to the form roller 6. When the operating lever 44 is shifted to the position III from the position II, first the form roller mechanism 7 is activated to cause the form rollers 6 and 6' to contact the plate cylinder 5. Then, the plate loading device 1 is operated by the switch 95 with a time delay, starting from the operation of the form roller mechanism 7, to carry out the plate loading operation and the pump motor (not shown) to provide suction for sheet feed device 21 is also operated for preparation of the sheet feeding operation. Thereafter, the operating lever is set at the position IV to force the plate cylinder 5 to contact the rubber blanket cylinder 8 in order to carry out the transferring operation.
When the operating lever is moved through the position V to the position VI, the sheet feeding mechanism 21 is activated to feed printing sheets. If, in this case, the operating lever is released, it will automatically return to the position V so that the printing operation can be carried out. Upon completion of the printing operation, the operating lever 44 is returned by the operating lever returning mechanism 78. When the operating lever 44 returns to the position III, the form rolls 6 and 6' are moved away from the plate surface. When the operating lever 44 reaches the position II, the plate unloading operation and the blanket cylinder cleaning operation are started by the switch 96. With the operating lever 44 at the position II, the operation of the water duct roll mechanism 10 is stopped. When the lever 44 is returned to the position I, all driving operations are halted.
As is clear from the above description, in the automatic printing machine according to the invention, before a plate is loaded onto the plate cylinder 5, the water duct roll mechanism 10 is operated after which the form duct roller mechanism is activated to cause the form rollers to contact the plate cylinder 5. That is, the plate loading operation is effected after the form rollers 6 and 6' have been brought into contact with the plate cylinder 5. Therefore, the contact pressure of the form rollers 6 and 6' causes the original plate 2 to be satisfactorily fitted onto the plate cylinder 5 from the beginning of the loading operation. Accordingly, only the pattern region of the plate can be coated with ink by the form rollers 6 and 6' from the beginning of the printing operation. Even if ink is applied to the plate cylinder 5 before a plate is loaded and the plate is loaded before the ink is removed, the ink applied outside the plate is removed by the form rollers 6 and 6'. Accordingly, if, after ink other than that in the pattern region has been removed, the ink on the pattern region is transferred onto the rubber blanket cylinder 8, the printing operation will be satisfactorily carried out beginning with the first printing sheet after the original plate has been loaded on the plate cylinder.
The form rollers 6 and 6' are brought into contact with the plate cylinder 5 in a manner described above. The water duct roller mechanism 10 is activated to supply water before the form rollers 6 and 6' come into contact with the plate cylinder 5 while the surface of the plate cylinder 5 is hydrophilic, and accordingly inking the surface of the plate cylinder is difficult. Thereofore, there will be little if any contamination with ink of the portion of the plate cylinder which is exposed outside the original plate. However, if any contamination occurs, the ink will be readily and positively removed by the form rollers 6 and 6' so that troublesome ink stains on the plate cylinder are entirely eliminated. Accordingly, the printing operation is carried out satisfactorily beginning with the first printing sheet.
Even if ink is applied to the plate cylinder 5 when the form rollers 6 and 6' contact the plate cylinder 5, such ink will be removed by the form rollers 6 and 6' after the latter have made several revolutions. If the plate is loaded on the plate cylinder 5 thereafter, the above-described advantageous effect will be similarly obtained because, in this case, the rear side of the plate will not be contaminated with ink and the portion of the plate cylinder which is exposed outside the plate will not be stained with the ink. This can be achieved by applying a plate loading signal to the solenoid 97 through a counter or a timer by opening the switch 95. | An automatic printing machine including an automatic plate loading device wherein a water duct mechanism is first activated after which a form roller mechanism is operated to cause form rollers to contact a plate cylinder. After this, the plate loading device forms a plate loading operation in which an original plate is satisfactorily fitted onto the plate cylinder wherein the plate surface is prevented from being contaminated by ink. Satisfactory printing results are obtained as soon as the plate is loaded onto the plate cylinder so that the first printing sheet is satisfactory and there is no waste of printing sheets. | 1 |
This is a Continuation of International Appln. No. PCT/GB95/00964 filed Apr. 27, 1995 which designated the U.S.
FIELD OF THE INVENTION
The present invention relates to the field of biochemistry and molecular biology, and is especially concerned with assays of nucleic acid for detecting and/or locating mutations therein, especially point mutations or insertion/deletion mutations involving the bases of just a few sequential nucleotides in, for example, the DNA of genes coding for proteins. Particularly in connection with this last aspect, the invention can have useful practical applications in biotechnology and medical diagnostics.
BACKGROUND
As is common knowledge, mutations can arise in sections of the nucleotide strands of genomic DNA either by deletion or insertion of part or all of a nucleotide base sequence or by an alteration of one or more nucleotide bases. Transcription from such mutated DNA sections ray then lead to defective protein products. Such defective protein products can be a cause of many genetic diseases or disorders. Such defective protein products that arise in fermentation processes in biotechnology may also be dysfunctional or harmful.
The ability to detect mutations in coding and non-coding DNA is important for the diagnosis of inherited disease. Nucleotide changes in a normal (i.e. wild-type) gene sequence are called gene mutations and can be either harmful or harmless. For example, a harmful gene mutation can be a single base pair change in a gene encoding an essential protein. A single base pair change or small insertion or deletion can result in a frame shift, a stop codon, or a non-conservative amino acid substitution, each of which can result in an inactive protein. A harmless gene mutation can be a gene polymorphism which results in a protein product with no detectable change in normal function. Mutation in non-coding DNA can also lead to disease, as in, for example, mutations in non-coding splice sites (found in certain cases of cystic fibrosis disease for instance) or mutations in transcriptional regulatory elements (found in certain defects of β-globin genes).
It is possible to form four sets of nucleotide mismatches when a mutant and normal DNA segment are annealed together. These sets include: G:A/C:T, C:C/G:G, A:A/T:T, and C:A/G:T. Each nucleotide pair represents eight possible single base pair mismatches which could be found in a DNA heteroduplex. However, DNA:RNA and RNA:RNA heteroduplexes can also be formed. Where a heteroduplex includes RNA, 9 single base pair mismatch sets are possible. DNA:DNA, DNA:RNA and RNA:RNA heteroduplexes can also be created by insertion or deletion of nucleotides in the mutant nucleic acid strand.
One example of a harmful mutation is provided by the well-known case of sickle cell anaemia where a point mutation involving an alteration of but a single nucleotide base, namely the substitution of a specific adenine by thymine in the genomic DNA, is responsible for the defect. In the case of cystic fibrosis the disease can arise from the presence of any one of a number of possible point mutations or small insertions or deletions that have been identified in different parts of the cystic fibrosis transmembrane regulator (CFTR) gene. Mutations in genomic DNA encoding oncogenes and tumour suppressors are also believed to be responsible for cell proliferation that causes many cancers.
Various methods of testing and detecting mutations in nucleic acids are known, many of which use for example a preliminary stage of polymerase chain reaction (PCR) amplification. Many of the existing methods are limited to cases where the precise nature and location of the mutation or molecular change being sought is already known and/or is of a particular kind. However, in many instances of disease-causing mutations the precise nature and location of the mutations are not known. A number of known methods of detecting unknown mutations in nucleic acids, such as SSCP, heteroduplex analysis, RNAse protection and chemical cleavage of heteroduplexes, are discussed in a review article by Markus Grompe entitled "The rapid detection of unknown mutations in nucleic acids" published 1993 in Nature Genetics, 5, 111-117. As yet there is no universal ideal method available and there is a need for more sensitive, rapid and efficient methods of detecting mutations in DNA. Such methods should also be capable of locating in a target nucleic acid or gene the position of point mutations or small mutations involving only a few bases.
When a mutation occurs in normal double stranded DNA of a living organism, initially this will generally affect one strand only of the duplex molecule, causing a mismatch in the base pairing. For example, with the occurrence of a point mutation a nucleotide cytosine base (C) in one strand may be changed so that the complementary quanine base (G) in the other strand becomes opposed to an adenine (A) or to a thymine base (T), producing a base-pair mismatch in the duplex molecule. However, certain proteins and enzymes, referred to as "proof-reading" proteins or enzymes or "DNA mismatch repair proteins or enzymes", are usually present in most living organisms and these enzymes act to detect such base-pair mismatches and to initiate a repair process in the mutated region before the molecules replicate and pass on the defect to subsequent copies of the DNA. One example of a set of such mismatch "repair enzymes", believed to be present in all living organisms, is provided by the Mut series of proteins and homologues thereof. A very well characterised system of these Mut repair enzymes, occurring for example in the bacterium E.coli, has been described by Paul Modrich and colleagues (for Review article, see for example Modrich, P. (1991), Annual Rev. Genet., 25, 229-253), a set of three proteins having been identified and purified which are termed MutS, MutH and MutL. These detect errors in DNA replication by interacting with double-stranded nucleic acid molecules containing mismatched base pairs that arise when errors and new mutations occur. The DNA-repair protein MutS in particular is a highly conserved protein which has the ability to detect and bind to the sites of mismatched bases (other than C:C) or deletions or insertions of up to four bases (see for example paper by Shin-San Su and Paul Modrich, "Escherichia coli mutS-encoded protein binds to mismatched DNA base pairs" (1986) Proc. Natl. Acad. Sci. U.S.A., 83, 5057-5061). MutS then recruits the MutH and MutL enzymes to create a nick at a CATG sequence near the mutation. Other enzymes then repair that region between the mutation and the nick (see also R. S. Lahue et al, "DNA Mismatch Correction in a Defined System" (1989) Science 245, 160-164).
The ability of various known mismatch repair enzymes to seek out and interact with mismatch regions in duplex DNA molecules has already led to some proposals for using such enzymes in assays to detect mutations responsible for such mismatches. Thus, in WO 93/02216 (Upstate Biotechnology, Inc., Lake Placid, N.Y., U.S.A.) a method for detecting mutations such as a single base change or an addition or deletion of about one to four base pairs in duplex nucleic acid molecules or polynucleotides is disclosed which is based on the use of a DNA mismatch-binding protein such as MutS in conjunction with a method using antibody reagents or the like for specifically recognizing or detecting the presence of said protein bound to nucleic acid or polynucleotide molecules. WO 93/20233 (University of Maryland at Baltimore) discloses a method for detecting single base pair mismatches at a preselected site in nucleic acids such as genomic DNA which is also based on the use of enzymes that repair mismatches in nucleic acids. In this latter method, however, mast emphasis is given to the detection of base pair mismatches at particular sites using mismatch repair enzymes having endonuclease activity that specifically cleave nucleic acid strands near to mismatches. Neither of the methods disclosed in the two above-mentioned patent publications, however, appear to be well-suited for determining the location of unknown mutations in nucleic acids, and in WO 93/02216 in particular the method appears to be concerned specifically with determining whether a particular sample of DNA includes a mismatch mutation without consideration of locating any such mutation that may be detected.
In a technique developed by Schmitz and Galas Schmitz, A, and Galas, D. J. (1978) DNaseI footprinting: A simple method for the detection of protein-DNA binding specificity." Nucleic Acids Research, 5, 3157-3170! for the study of sequence-specific binding of proteins to DNA, a DNA fragment is exposed to a sequence-specific DNA binding protein. After such time as to allow for binding, the protein-DNA complex is treated with DNaseI. The bound protein shields that region of DNA to which it is bound from digestion by DNaseI, and after separation of the reaction products by gel electrophoresis, the protected region is seen as a gap in the otherwise continuous background of digestion products.
Footprint analysis has also been accomplished using DNA digesting enzymes which are processive, i.e. act on the DNA in a 3' to 5' fashion. The prototype enzyme which has been used for this type of assay is Exonuclease III. The procedure for such exonuclease footprinting involves binding of sequence specific DNA binding protein to the DNA followed by exonuclease digestion. As with the above-mentioned technique using DNase, the bound protein protects the DNA from digestion. , due to the processive nature of the exonuclease, the reaction products do not consist of a background of randomly cleaved DNA fragments, rather they consist of two single stranded species which overlap and form double standed DNA only in the region of the DNA-protein interaction. Thus, after separation by gel electrophoresis, the region of DNA-protein interaction may be deduced by the lengths of the two single stranded reaction products.
It is to be noted, however, that in none of the afore-mentioned prior art has there been any disclosure of a footprinting or similar technique involving endonucleases or exonucleases being used to detect mutations in DNA.
SUMMARY OF THE INVENTION
Insofar as the present invention in its main aspect concerns assays to detect mutations or base mismatches occurring in nucleic acid molecules, it is based on a principle of forming heteroduplex nucleic acid molecules in which strands derived from an original nucleic acid test sample are paired with non-mutant strands from a corresponding reference sample. Said reference sample may, for example, be provided by the wild-type non-mutated nucleic acid or derivative thereof, for example a cloned DNA or amplified PCR derivative or an equivalent synthetic oligonucleotide. A mismatch-binding protein or repair enzyme, such as the MutS protein or homologues thereof for example, or other mismatch-binding protein(s) as herein disclosed, is then used to seek cut and bind to any relevant mismatch site in the heteroduplex molecule resulting from point mutations or from insertions or deletions of a few sequential nucleotide bases in the strands from the test sample. Upon then digesting the reaction mixture with an exonuclease all the nucleic acid molecules without any mismatches or small insertions or deletions are digested and completely removed. Heteroduplex molecules containing mismatches or small insertions or deletions will be detectable because the bound protein acts to block-the exonuclease and protect the underlying strands from its action. Thus, residual single strand fragments will only be derived from the mismatch-containing hetero-duplex molecules. Analysis of these single strand fragments can then enable the locus of the mismatched bases to be determined.
In a particularly preferred procedure the DNA protected by the bound mismatch-binding protein or repair enzyme is detected by digesting the nucleic acid reaction mixture with an exonuclease enzyme having a specific unidirectional exonuclease activity, under conditions in which the exonuclease enzyme progressively removes or deletes nucleotides from one end of each nucleic acid strand until reaching the site of a base-pair mismatch bound to the mismatch-binding protein or repair enzyme. The latter then blocks and protects against further exonuclease digestion along the strand. For such heteroduplex DNA molecules containing a mutation and mismatch of bases there is therefore no complete degradation by the exonuclease enzyme, and the presence of incompletely degraded relatively large DNA fragments can then be detected by various methods. By then determining the size of the fragments the location of the mismatch region and of the mutation may also be ascertained.
Thus, according to one aspect the invention provides a method for detecting a mutation in a test sample of target nucleic acid, said method comprising
a) providing a control sample of reference nucleic acid capable of hybridizing to strands of the target nucleic acid from said test sample;
b) denaturing if necessary said reference nucleic acid and said target nucleic acid, or replicates thereof, forming single-stranded reference nucleic acid and single-stranded target nucleic acid;
c) annealing said single-stranded reference nucleic acid and said single-stranded target nucleic acid, wherein said annealing is sufficient to form heteroduplex nucleic acid composed of one strand derived from said target nucleic acid hybridized with a second strand derived from said reference nucleic acid;
d) contacting said heteroduplex nucleic acid with a mismatch-binding protein capable of binding selectively to the site of said mutation;
e) treating said annealed nucleic acid material with an exonuclease, the presence of said mismatch-binding protein being sufficient to protect said nucleic acid to which it is bound from digestion by said exonuclease; and
f) detecting the presence of said protected nucleic acid as a indication of the presence of said mutation in said target nucleic acid.
In preferred embodiments the method further comprises determining the length of residual strand fragments of said protected nucleic acid, giving an indication of the location of said mutation. The determination of the length of such residual strand fragments, or size resolution and analysis thereof, is preferably carried out by gel electrophoresis, e.g. polyacrylamide gel electrophoresis (PAGE), of the denatured nucleic acid exonuclease digestion products whereby the nucleic acid fragments are separated according to their relative size. For detecting and visualising the size separated fragments in the gel a suitable label (e.g. a fluorescent dye or radioactive agent) may be incorporated at an earlier stage into the reference nucleic acid molecules, or suitable labelled probes and Southern blotting for example may be used where sufficient sequence information is already available in respect of the expected fragments from particular mutations. Other alternative size separation methods or techniques, however, may also be used if desired, including for example capillary electrophoresis, size exclusion chromatography, high performance liquid chromatography (HPLC) and thin layer chromatography (TLC).
The invention also provides a method for detecting single base mismatches or mutations in nucleic acid comprising the steps of
(a) generating heteroduplex nucleic acid molecules in which single strands derived from a sample of the target nucleic acid under test are hybridized with corresponding non-mutant single strands derived from a reference nucleic acid sample whereby mutant strands present in the original target nucleic acid test sample become paired with non-mutant-strands from the reference nucleic acid sample to form mismatch-containing heteroduplex nucleic acid molecules;
(b) contacting the nucleic acid material generated in step (a) with a mismatch-binding protein effective to seek out and selectively bind to mismatch sites in the heteroduplex molecules;
(c) digesting the nucleic acid material from step (b) with an enzyme having exonuclease activity whereby said enzyme progressively removes or deletes nucleotides from one end of each strand of the heteroduplex molecules until encountering said mismatch-binding protein bound to a mismatch site, said protein then acting to block further deletions and strand degradation by the exonuclease enzyme; and
(d) analysing the nucleic acid digestion products from step (c) to determine the size or sizes of remaining single stranded nucleic acid fragments.
The presently preferred mismatch-binding protein for use in carrying out the invention is a MutS encoded protein such as the commercially available E.coli MutS protein from the Mut repair protein series. This is effective, albeit with somewhat different affinities, to bind to mismatch regions produced by most of the different possible base mismatch pairings within a range of one to about four nucleotides. Other mismatch-binding proteins or repair enzymes, however, may also be used. These may be similar to or homologues of the above-mentioned MutS protein and will have equivalent characteristics insofar as the detection and binding to mismatch regions of interest in heteroduplex DNA molecules is concerned and ability to protect nucleic acid strands to which they are bound against exonuclease digestion. Such other mismatch-binding proteins include, for example, HexA, from Streptococcus pneumoniae, MutS from Salmonella typhimurium, MutS from A. Vinlandii, MSH 1 from Saccharomyces cerevisiae, HMSH2 from humans, MMSH2 from mouse, XMSH2 from Xenopus, and p160 from humans
Various exonucleases or DNA polymerases containing exonuclease activity may be used for the digestion stage, including exonuclease III, T4 DNA polymerase, Vent (Pol-ve) polymerase, bacteriophage lambda exonuclease and T7 DNA polymerase. The presently preferred enzyme, however, is T7 DNA polymerase which has a specific processive 3' to 5' exonuclease activity.
In carrying out the invention, the original target nucleic acid of the test sample and also the reference nucleic acid will usually first be subjected to amplification either by cloning or, more conveniently, by using a conventional PCR amplification technique with appropriate primers and a high fidelity Taq polymerase.
In preferred embodiments, the reaction mixture containing the heteroduplex nucleic acid molecules is treated with the mismatch binding protein such as the MutS protein under slightly alkaline conditions, most preferably in the pH range of 8.0 to 8.5, and in the presence of a divalent cation such as Mg ++ which should normally be at a concentration of at least 7 mM, and preferably at a concentration of about 8 mM. The temperature, however, at which the treatment with the mismatch binding protein is carried out is not usually critical, at least not with MutS, and may be within the range of about 0° C. to about 30° C. for example.
For marketing and practical use, all the basic essential materials and reagents required for carrying out the detection method of the present invention may be assembled together in a self-contained kit. Such kits thus provide another aspect of the invention. Such kits will include one or more mismatch-binding proteins or repair enzymes capable of seeking out and binding to mismatch sites in heteroduplex molecules and an enzyme having specific unidirectional exonuclease activity, each reagent being in a separate container comprised within the kit, together with appropriate buffer and instructions for use. Assuming optional PCR amplification is to be used such kits may also include preselected primers, preferably detectably labelled, for PCR amplification of a particular fragment of a specific nucleic acid sequence or gene, Taq polymerase enzyme, a mix of deoxynucleotides and buffers to provide the necessary reaction mixture for carrying out selective PCR amplification.
The invention also provides a method for screening or testing human or animal subjects for the presence of a suspected genetic defect or mutated gene related disease, said method comprising obtaining nucleic acid from said subject and using that nucleic acid as the target nucleic acid in carrying out a method of detecting and localising a mutation as herein disclosed.
The original target nucleic acid of the test sample will generally comprise double-stranded genomic or cloned DNA or may be cDNA derived possibly from mRNA. The reference nucleic acid providing a control saddle will also frequently be provided by a fragment of double-stranded DNA, particularly non-mutated wild-type genomic DNA, or cloned DNA or cDNA, or even a synthetic oligonucleotide, all of which varieties are to be regarded as being covered by, and included within, the term "nucleic acid" as used herein.
The invention, and an example of the manner in which it may be carried cut in practice to detect mutations in genomic DNA, will now be described in more detail with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an annotated diagram illustrating the general principle involved in using a MutS DNA mismatch-binding protein or repair enzyme to detect and bind to a nucleic acid duplex molecule at the location of a base pair mismatch, and in then digesting the nucleic acid with an enzyme having a specific 3'-5' exonuclease activity in order to enable the MutS binding subsequently to be detected and located by resolving and separating the residual single stranded fragments according to size using, for example, denaturing gel electrophoresis;
FIG. 2 illustrates the nucleotide base sequence (SEQ ID NO: 1) of a fragment of the human cystic fibrosis transmembrane regulator (CFTR) gene containing, between flanking sequences, the CFTR exon 11 (GenBank accession number M55116) in which the locations of four known but different alternative point mutations, designated 1717-1 G>A, S549N, G55lD and R553X respectively, are indicated;
FIG. 3 shows the base sequence of fluorescent labelled synthetic oligonucleotide priers used for PCR amplification of a 492 base pair (bp) sequence of the genomic DNA fragment depicted in FIGS. 2, 3(a) being the sequence (SEQ ID NO: 2) of one primer that is labelled with a blue fluorescent dye (designated FAM) and 3(b) being the sequence (SEQ ID NO: 3) of the second primer which is complementary to the sequence at the other end of the selected 492bp fragment and which carries a label consisting of a green fluorescent dye (designated JOE);
FIGS. 4(a) and 4(b) illustrate the detection of the 1717-1 G>A mutation in the CFTR exon 11 sequence indicated in FIG. 2 after subjecting a PCR amplification product thereof, obtained using the primers of FIG. 3, to a method of mutation detection in accordance with the present invention, this method involving digestion of the PCR product that contains mutation mismatch heteroduplex molecules with a MutS mismatch-binding protein or repair enzyme, followed by degradation with a 3' to 5' exonuclease, size separation of the resulting DNA fragments by denaturing polyacrylamide gel electrophoresis, and then optically detecting the fluorescent dye label of relevant fragments, wherein (a) represents the spectrum obtained in relation to the FAM primer carrying the blue fluorescent label on one strand and (b) represents the spectrum obtained in relation to the JOE primer carrying the green fluorescent label on the complementary strand; and
FIGS. 5(a) and 5(b), 6(a) and 6(b), and 7(a) and 7(b) are each two part diagrams corresponding to FIG. 4 but illustrating respectively the detection of other mutations S549N, G55lD and R553X.
DETAILED DESCRIPTION
In FIG. 1 a MutS mismatch-binding protein or repair enzyme is diagrammatically depicted bound to a mismatch region of a heteroduplex nucleic acid molecule which is suitably labelled at the 5' end of at least one strand, and an enzyme having a specific 3' to 5' exonuclease activity is depicted on each strand while progressively degrading the latter from their 3' ends prior to a subsequent stage of analysis to resolve and separate the nucleic acid strand fragments according to size.
In the specific example to which FIGS. 2 to 7 of the drawings relate, the invention was tested by being used to detect commonly occurring known mutations in exon 11 of the human cystic fibrosis transmembrane regulator (CFTR) gene which provides a test model for evaluating the method.
A 492 base pair DNA amplification product of the CFTR gene was generated first by PCR using synthetic oligonucleotide primers (purchased from Applied Biosystems) having the nucleotide sequences (SEQ ID NO: 2 and SEQ ID NO: 3) shown in FIG. 3 and labelled with blue and green fluorescent dyes, these being designated FAM and JOE respectively. Using the above-mentioned fluorescent primers under standard PCR conditions, as described for example in the paper entitled "Primer-directed enzymatic amplification of DNA with a thermostable DNA polymerase" by Saiki et al (1988) Science 239, 487-91, using 58° C. annealing temperatures and a high fidelity Taq polymerase (Perkin-Elmer Ampitaq™ N801-0060), thirty cycles of amplification were carried out from an initial sample of human genomic DNA made up of wild type reference DNA and target DNA in approximately equal amounts. The wild type reference DNA had a sequence corresponding to FIG. 2 without mutations (standard DA), whilst the target DNA being tested (obtained from human patients afflicted with cystic fibrosis) had a sequence corresponding to FIG. 2 but containing one of the four different mutations indicated therein. This produced samples of amplified DNA labelled with FAM at one end and JOE at the other end of the molecule.
The "standard" PCR conditions referred to above comprised denaturing for 5 minutes at 93° C., then performing 30 cycles each comprising successive temperature levels of 95° C. for 1 minute, 58° C. for 1 minute and 72° C. for 1 minute. Final extension was at 72° C. for 5 minutes. Buffer was Tris (pH 8.4) 10mM, KCl 50mM, MgCl 2 1.5mM, dNTP 200uM. Of the primers, 50 pmoles each were used in a 50 μl reaction mixture. Human genomic DNA used was 50ng in a 50 μl volume of reaction mixture. Taq polymerase was used at 1 unit per 50 μl reaction mixture.
The PCR products were then purified by centrifugal microfiltration or dialysis using Centricon™ 100 tubes (Amicon) which removed excess primers and other reagents. In each case the PCR product (50 μl) was diluted to 2 ml in TE buffer, pH 8, and concentrated to a final volume of 25-30 μl. The final wash used exonuclease buffer (50mM Tris, pH 7.5, 7mM MgCl 2 , 5mM DTT), and the DNA content of the purified PCR product was determined by measurement of the optical density at 260 nm (OD 260). It may be noted that subsequent heteroduplex formation occurs better in the absence of Taq polymerase, so the Centricon step was included to remove this and other PCR reagents. Thus no new DNA synthesis occurs which might interfere with heteroduplex formation.
The PCR product (20 μl to 30 μl) in 100mM NaCl, 10mM Tris (pH 7.5) and 1mM EDTA, was then heated to 95° C. for five minutes, followed by cooling to 65° C. over a 60 minute period so as to promote the formation of heteroduplex molecules by hybridization of one strand of the non-mutant wild type DNA with a strand of the test DNA that contains a mutation. This heteroduplex formation was also carried out in exonuclease buffer, i.e. 50mM Tris, pH 7.5; 7mM MgCl 2 , 5mM dithiothreitol. The reaction mixture containing the heteroduplex molecules thus formed was then either used immediately or stored at -20° C. until use.
2 pmole (1-5 pmole ranges seem to work) of the DNA mixture containing the heteroduplex molecules produced (expected to be 50% heteroduplex, 50% homoduplex) was then treated in the next stage with a preparation of the MutS protein to promote binding of the latter to the heteroduplex molecules at the site of mismatched bases. In more detail, 5 pmoles of MutS protein (purchased from United States Biochemicals Ltd.--catalogue number 71422--and stored at -20° C. until use), 5 μl of dilution buffer (containing 50mM Hepes, 100mM KCl, 1mM EDTA, and 1mM DTT) was mixed and incubated on wet ice for 1 hour with the 2 pmoles of the DNA in 15 μl of buffer (pH 7.5) containing 50mM NaCl, 10mM Tris-Cl, 7mM MgCl 2 and 1mM EDTA made up to a total final volume 20 μl (subsequently, it has been found that a higher pH in the range of 8 to 8.5, preferably 8.5, can be beneficial, and that the Mg ++ concentration may advantageously be increased to 8mM. Also, the MutS binding can be performed if desired at higher temperatures, for example at least up to about 30° C.). After incubation on wet ice for 1 hour, 10 units of T7 polymerase (a processive exonuclease obtained from New England Biolabs--catalogue number 256S) were added and the tube was transferred to a 37° C. waterbath. The actual amount of T7 polymerase used has varied in different experiments between 5 and 10 units, but generally better signal- to-noise ratios have been seen using 10 units. After digestion for 3-5 minutes, this time being judged sufficient to ensure complete degradation of all duplex DNA molecules free of mutations and therefore not bound to the MutS protein, the reaction was stopped by the addition of 10 μl gel loading buffer (deionised formamide containing 10mM EDTA). The samples were heated to 90° C. to denature the DNA and were then loaded, together with reference standards of known size (Applied Biosystems Rox 2500), onto a polyacrylamide sequencing gel (6% concentration, containing 7M Urea) for analysis.
In this example the apparatus used for analysis was a model 373 automated DNA sequencer of Applied Biosystems Inc. using Applied Biosystems 672 Genescanner™ software. This gave the results which are illustrated in FIGS. 4 to 7 and which are summarised in Table 1 at the end of the present description, fragment sizes being estimated using a third order least squares approximation. As will be seen from FIGS. 4 to 7, in this example distinct peak were visible on both strands which were absent in control samples, and a good signal to noise ratio was obtained although some small background peaks were present.
The assay carried out substantially as described above has also been evaluated by testing other known mutations of the CFTR gene and thus far it has been shown to be capable of detecting also the mutations G85E, R75X, R75Q and P67L in CFTR exon 3.
It will of course be appreciated that in modifications of the method as described in the example above autoradiographic or other gel detection techniques could alternatively be used in carrying out the analysis provided they have sufficiently high resolution characteristics. Also, as already indicated, other size separation methods (particularly capillary electrophoresis, but also for example size exclusion chromatography, HPLC and thin layer chromatography) could readily be adapted to carry out the size separation process after the exonuclease treatment, if so desired. In addition, other labelling methods which could be used include the use of radiolabelled primers or PCR products, or instead of labelling the nucleic acid strands before digestion with the exonuclease enzyme silver staining or any other suitable DNA detection methods could be used to detect the DNA fragments after digestion and electrophoresis.
The best exonuclease activity found so far has been seen with the exonuclease activity of T7 DNA polymerase which is the presently preferred enzyme as previously mentioned, but other enzymes with processive, preferably unidirectional, exonuclease activity (either 3'-5' or 5'-3') can also be suitable. In particular it may be found advantageous to use lambda exonuclease or Vent polymerase (Pol-ve) available from New England Biolabs.
Although the MutS enzyme is presently the preferred mismatch-binding protein, other mismatch-binding proteins could also be used which may provide greater stability, including homologues of MutS, for example the human MutS homologue hMSH2, or in some cases it may be found advantageous to use mixtures of Mut proteins or other mismatch-binding proteins. It may also be possible as another advantageous alternative to use proteins which are not necessarily involved in repair of mutations but which nevertheless have a similar strong binding affinity specifically for base pair mismatch regions of nucleic acid molecules, for example the so-called Holiday junction binding RuvC protein from E. coli. If desired, genetic engineering techniques such as site directed mutagenesis may also be employed to modify artificially MutS protein or homologues thereof so as, for example, to increase stability or improve sensitivity and binding characteristics. Also, in a further modification, stability of the heteroduplex molecules carrying the MutS or other mismatch-binding protein bound thereto may be improved by treatment with a chemical cross-linking agent, e.g. formaldehyde, before commencing the treatment with the exonuclease, thereby to cause the protein to be bound even more strongly for resisting and blocking the action of the exonuclease.
Various other modifications are of course also possible within the scope of the invention which includes all novel and inventive features and aspects herein disclosed, either explicitly or implicitly and either singly or in combination with one another. In particular, the scope of the invention is not to be construed as being limited by the illustrative examples or by the terms and expressions used herein merely in a descriptive or explanatory sense.
TABLE 1______________________________________ Observed Distance from Observed Distance fragment primer to fragment from primer size mutation size to mutationMutation (blue) (blue) (green) (green)______________________________________wild type none NA none NA1717-1 G > A 189 184 326 307S549N 253 245 263 246G551D 259 250 256 241R553X 269 256 246 235______________________________________
__________________________________________________________________________# SEQUENCE LISTING- (1) GENERAL INFORMATION:- (iii) NUMBER OF SEQUENCES: 3- (2) INFORMATION FOR SEQ ID NO: 1:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 613 base (B) TYPE: nucleic acid (C) STRANDEDNESS: double (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: DNA (genomic)#1: (xi) SEQUENCE DESCRIPTION: SEQ ID NO:- ATATACCCAT AAATATACAC ATATTTTAAT TTTTGGTATT TTATAATTAT TA - #TTTAATGA 60- TCATTCATGA CATTTTAAAA ATTACAGGAA AAATTTACAT CTAAAATTTC AG - #CAATGTTG 120- TTTTTGACCA ACTAAATAAA TTGCATTTGA AATAATGGAG ATGCAATGTT CA - #AAATTTCA 180- ACTGTGGTTA AAGCAATAGT GTGATATATG ATTACATTAG AAGGAAGATG TG - #CCTTTCAA 240- ATTCAGATTG AGCATACTAA AAGTGACTCT CTAATTTTCT ATTTTTGGTA AT - #AGGACATC 300- TCCAAGTTTG CAGAGAAAGA CAATATAGTT CTTGGAGAAG GTGGAATCAC AC - #TGAGTGGA 360- GGTCAACGAC CAAGAATTTC TTTAGCAAGG TGAATAACTA ATTATTGGTC TA - #GCAAGCAT 420- TTGCTGTAAA TGTCATTCAT GTAAAAAAAT TACAGACATT TCTCTATTGC TT - #TATATTCT 480- GTTTCTGGAA TTGAAAAAAT CCTGGGGTTT TATGGCTAGT GGGTTAAGAA CA - #CATTTAAG 540- AACTATAAAT AATGGTATAG TATCCAGATT TGGTAGAGAT TATGGTTACT CA - #GAATCTGT 600# 613- (2) INFORMATION FOR SEQ ID NO: 2:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 24 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: other nucleic acid (A) DESCRIPTION: / - #desc = "Oligonucleotide"#2: (xi) SEQUENCE DESCRIPTION: SEQ ID NO:# 24ACCA ACTA- (2) INFORMATION FOR SEQ ID NO: 3:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 24 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: other nucleic acid (A) DESCRIPTION: / - #desc = "Oligonucleotide"#3: (xi) SEQUENCE DESCRIPTION: SEQ ID NO:# 24CCCA TAAT__________________________________________________________________________ | A method for detecting and locating mutations in DNA involves forming heteroduplex molecules by hybridizing single strands derived from a sample of target DNA under test with single strands derived from a sample of non-mutant reference nucleic acid so that any mutation causing an alteration in one or more nucleotide bases in the target DNA produces a base pair mismatch in the corresponding heteroduplex molecule. The nucleic acid mixture is then reacted with a mismatch-binding protein such as the mismatch repair enzyme Mut"S" which recognizes and binds to any such resultant mismatch site. Subsequent treatment with an exonuclease having unidirectional activity degrades duplex molecules free of mismatches but mismatch-containing heteroduplex molecules are protected by the mismatch-binding protein bound to the mismatch sited therein and this limits the extent of the exonuclease degradation. The degradation products are then analyzed, e.g. by get electrophoresis, to determine the size of residual single-stranded nucleic acid fragments and hence to establish the location of the mutation. This method has useful applications in medical diagnosis and biotechnology. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a U.S. national phase application under 35 U.S.C §371 of International Patent Application No. PCT/JP2014/057315, filed on Mar. 18, 2014, and claims benefit of priority of Japanese Patent Application No. JP 2013-055771, filed on Mar. 18, 2013. The international Application was published on Sep. 25, 2014, as International Publication No. WO 2014/148484 under PCT Article 21(2). The entire contents of these Applications are hereby incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to a lead frame for mounting semiconductor element, particularly, to the shapes of a semiconductor mounting part and a terminal part of the lead frame.
BACKGROUND OF THE INVENTION
For lead frames on which semiconductor elements are mounted, it is one of the important points for improving the reliability of products to improve adhesiveness of sealing resin to the terminal parts that are connected to semiconductor elements and to the outside. Accordingly, various technologies for improving adhesiveness of resin to prevent the terminal parts from coming out have been proposed. Specifically, these technologies include: a technology of forming a protrusion (eave-shaped portion) on the upper surface of terminal; and a technology of roughening the lateral surface of terminal.
For example, Japanese Patent Kokai No. 2011-151069 discloses a technology of making a lateral surface of a substrate rough by giving an etching treatment from the front and back surfaces of the substrate. This technology is a technology capable of coping with the above-described problem by making a difference between etching masks used for the front and back surfaces in a conventional etching process that has been performed in the prior art. In the technology disclosed in Japanese Patent Kokai No. 2011-151069, its objective is achieved by making a lead frame with etching masks that are formed in such a way that an etching mask used for the front surface is given narrow openings and an etching mask used for the back surface is given wide openings when the etching process is performed by the length substantially equal to or smaller than the thickness of the metal substrate.
Now, in the case where lead frames are made by the prior arts, a protrusion has to be formed in such a way that: the top end of the protrusion is substantially flat; or the cross section of the protrusion has an arc-like profile, because a crack occurs in a sealing resin in the case where the top end of the protrusion is sharp even though the protrusion is formed in order to improve adhesiveness of resin to terminal parts.
In the case of QFN (quad flat non-leaded package) or lead frames for LED in particular, an edge face of a device-mounting plane is designed to overhang an edge face of a plane that is exposed after semiconductor packaging, to function as one of measures for preventing resin from peeling off from a lead frame. However, the trouble which is acknowledged as problem in the present field is that resin inevitably peels off from a lead frame because of influences of: expansion or contraction of resin due to thermal history at high temperatures; and vibration, the expansion or contraction and vibration occurring due to friction between a lead frame sheet and a blade when the lead frame sheet is cut off into strips. Accordingly the marketplace in this field requires better improvement of adhesiveness of resin to lead frame.
Accordingly, the present invention is made in view of the above-described problem. The objective of the present invention is to offer a lead frame for mounting semiconductor element which effectively satisfies adhesiveness of sealing resin to lead frame.
SUMMARY OF THE INVENTION
In order to achieve the above-described objective, a lead frame for mounting semiconductor element according to one of embodiments of the present invention is characterized: in that the lead frame includes a protrusion that is provided on one of or both of lateral sides of at least one of its semiconductor-mounting part and its terminal part and that horizontally projects from edges of upper and lower surfaces of the semiconductor-mounting part or the terminal part; and in that the protrusion is formed in such a way that: the top end of the protrusion is approximately flat or the cross section of the top end of the protrusion has an arc-like profile; and the top end of the protrusion is thick.
Also, a lead frame for mounting semiconductor element according to one of the embodiments of the present invention is characterized in that a protrusion is formed on one of or both of lateral sides of at least one of its semiconductor-mounting part and its terminal part, in that the upper side of the protrusion horizontally projects beyond an edge of the lower surface of the semiconductor-mounting part or the terminal part, in that the protrusion runs slantingly and downward from the lower side of the projecting upper side of the protrusion so that the protrusion horizontally projects beyond an edge of the upper surface of the semiconductor-mounting part or the terminal part and also projects downward from the upper side, and in that the top end of the protrusion is 25 μm or more in thickness and is rounded.
Also, a lead frame for mounting semiconductor element according to one of the embodiments of the present invention is characterized in that a protrusion is formed on a lateral side of at least one of its semiconductor-mounting part and its terminal part, in that the upper side of the protrusion horizontally projects beyond an edge of the lower surface of the semiconductor-mounting part or the terminal part, in that the protrusion horizontally projects on the lower side of the projecting upper side of the protrusion beyond also an edge of the upper surface of the semiconductor-mounting part or the terminal part, and in that the protrusion further includes a portion running downward from a lower-side corner of the top end of the protrusion.
According to one embodiment of the present invention, a protrusion is formed on a lateral surface of the semiconductor-mounting part or the terminal part to run not only horizontally but also vertically, so that the protrusion makes lead frame have high tolerance for stress in all directions and increases a contact area between the metal substrate and resin. As a result, it is possible to prevent the resin from peeling off from the metal substrate due to expansion or contraction caused by thermal history when a lead frame sheet is cut off into strips or due to vibration occurring when the lead frame sheet is cut off into strips.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view for explaining a process of formation of a protrusion through trial example leading to the present invention, while a primary part is being enlarged.
FIG. 2 is a view for explaining the shape and size of the top end of the protrusion formed in the process which is shown in FIG. 1 , while the primary part is being enlarged.
FIG. 3 is an explanatory view for explaining formation of the protrusion according to one embodiment of the present invention.
FIG. 4 is a view for explaining a process of formation of the protrusion according to one embodiment of the present invention, while the primary part is being enlarged.
FIG. 5 is a list showing the relation between: etching conditions for forming the protrusion according to one embodiment of the present invention; and variations in shape and size of the cross section of protrusion.
FIG. 6 is a view for explaining a process of formation of a protrusion according to another embodiment of the present invention, while the primary part is being enlarged.
FIG. 7 is a photograph for explaining the shape and size of a protrusion according to an embodiment 2 of the present invention, while a primary part is being enlarged.
FIG. 8 is a photograph for explaining the shape and size of a protrusion according to an embodiment 3 of the present invention, while the primary part is being enlarged.
FIG. 9 is a photograph obtained by photographing the protrusion from the side of an exposed surface after sealing with resin, more specifically, at an angle at which a camera faces squarely to the top end of the protrusion, in order to show a state of rough surface in one embodiment of the present invention.
FIG. 10 is a photograph obtained by photographing the under-side surface of the protrusion which is roughened and shown in FIG. 9 , from just below the under-side surface of the protrusion (and at an angle perpendicular to the surface of the metal substrate from the exposed-surface side before processing the surface of the metal substrate).
DETAILED DESCRIPTION OF THE INVENTION
A process of forming a pattern of the lead frame according to one embodiment of the present invention is characterized in that the process includes: a step of forming semiconductor-mounting parts and terminal parts on the surface of a metal substrate for lead frame in such a way that a photo sensitive resist layer is put on the metal substrate 1 for lead frame that is given alkaline-acid treatment and the photo sensitive resist layer is exposed with a mask for manufacturing lead frame which includes a pattern for forming protrusions so that the pattern is printed on the surface of the metal substrate; and a step of forming the shapes of lead frames each of which includes a protrusion on one of or both of the lateral sides of the semiconductor-mounting part or the terminal part by giving the metal substrate 1 for lead frame an etching treatment.
Regarding a method of forming the protrusions 4 , for example, the present inventors performed an etching process after forming resist layers with extremely narrow widths in the vicinity of the lateral sides of portions that were given shape patterns of the semiconductor-mounting parts respectively so that portions of the metal substrate for forming protrusions on which the resist layers for forming protrusions were formed were made to dissolve by the etching process slower than portions of the metal substrate for forming another parts except the protrusions did, and then the present inventors tried to form the protrusions after formation of the shapes of another parts expect the protrusions was completed.
In forming the protrusions by the above-described method, as shown in FIG. 1 , the resist layers 2 are formed on surface areas including the semiconductor-mounting parts and the resist layers 3 with extremely narrow widths are formed also on the opposite surface areas, or on the surface areas that are exposed to the outside after sealing with resin, and then the metal substrate having the resist layers is given an etching treatment. As a result, the protrusions 4 running horizontally from the surface areas including the semiconductor-mounting parts (packaging surface) and running vertically (downward) can be formed. However, the thicknesses of the formed protrusions 4 range from 10 μm to 15 μm and are very thin, and even slight difference in etching condition causes large variations in workmanship of the shapes of the protrusions, so that the protrusions may inevitably disappear and it is hard to keep the protrusions. Also, the top ends of the protrusions 4 have sharp shapes, so that there is a large fear that the top ends of the protrusions having sharp shapes might cause crack after sealing with resin (refer to FIG. 2 and the left-side figure of FIG. 3 ).
In order to avoid this matter, so that there is necessity to create condition to stably form the protrusions despite variations in etching conditions so as to make the thicknesses of the protrusions 4 as thick as possible, as shown in the right-side figure of FIG. 3 . As a method for overcoming the above-described problem, the present inventors tried to form the resist layers 3 having extremely narrow widths not only on the surface that is exposed to the outside after sealing with resin but also on the surface on which packaging is performed so that the thicknesses of the protrusions formed after etching treatment become thick, as shown in FIG. 4 . In this case, the conditions of the metal substrate 1 and the etching resist patterns 2 and 3 are same as those in embodiments 1, 4, and 5 which are explained below. As a result, the present inventors could make protrusions of 50 μm in thickness (refer to the middle part of the list shown in FIG. 5 ). In addition, the present inventors increased or decreased an amount of etching intentionally to confirm whether the protrusions disappeared or not. As a result, thick protrusions of 30 μm in thickness could be formed even though an amount of etching was increased (refer to the left part of the list shown in FIG. 5 ).
Also, the top end 5 of each of the protrusions 4 does not have a sharp shape but has a rounded shape (refer to the left-side part or the middle part of the list shown in FIG. 5 ) or an approximately plane-like shape (refer to the right-side part of the list shown in FIG. 5 ), and the present inventors could confirm that such a method made it possible to prevent crack in resin from occurring from the top end 5 of the protrusion after sealing with resin.
The case where the protrusion 4 is formed on one lateral side of each of the semiconductor-mounting parts was explained up to now. However, it goes without saying that protrusions can be formed on the both lateral sides of a semiconductor-mounting part or on one of and/or both of lateral sides of a terminal part in the same manner.
Embodiment 1
A band-shaped cupper material (KLF-194: made by Kobe Steel, Ltd.) having a thickness of 0.2 mm and a width of 180 mm was used as a metal substrate 1 for lead frame, and photo sensitive resist layers (negative-type photo sensitive resist AQ-2058: made by Asahi Kasei E-materials Corporation.) each having a thickness of 20 μm were formed on the both surfaces of this metal substrate respectively. And then, in order to form a protrusion 4 , the both surfaces of the metal substrate 1 that were given the photo sensitive resist layers respectively were exposed to be developed through glass masks (HY2-50P: made by KONIKA MINOLTA ADVANCED LAYERS, INC.), one of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer having a width A of 40 μm on the packaging-surface side and the other of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer having a width B of 80 μm on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ), so that etching resist pattern layers for lead frame each having an etching resist pattern for forming a protrusion 4 (dummy pattern for controlling etching rate) were formed. And then, the metal substrate 1 having been provided with the etching resist pattern layers that had the patterns for forming protrusion was given an etching process. As a result, the extremely thin etching resist layers 3 for forming protrusion which were given on the both surfaces of the metal substrate 1 slowed down progress of etching for the portion, so that a shape of lead frame which included a protrusion 4 having a width E of 70 μm (an amount of the protrusion projecting from the edge of the upper surface in the horizontal direction), a height G of 100 μm (an amount of the protrusion projecting from the upper surface in the downward direction), and a thickness F of 50 μm was formed. Afterward, the etching resist layers were removed from the metal substrate, so that a band-shaped copper lead frame was obtained (refer to the central part of the list shown in FIG. 5 ). In this case, an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width C of 40 μm on the packaging-surface side, and an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width D of 120 μm on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ). Afterward, the band-shaped lead frame was plated with metal as it was, to have extremely thin metal layers. Afterward, the band-shaped lead frame was cut off into fine pieces along its transverse direction, and then resin tapes for fixing sealing resin were stuck on these fine pieces respectively, to obtain finished lead frame sheets.
Embodiment 2
A band-shaped cupper material (KLF-194: made by Kobe Steel, Ltd.) having a thickness of 0.2 mm and a width of 180 mm was used as a metal substrate 1 for lead frame, and photo sensitive resist layers (negative-type photo sensitive resist AQ-2058: made by Asahi Kasei E-materials Corporation.) each having a thickness of 20 μm were formed on the both surfaces of this metal substrate 1 respectively. And then, in order to form a protrusion 4 , the both surfaces of the metal substrate 1 that were given the photo sensitive resist layers respectively were exposed to be developed through glass masks (HY2-50P: made by KONIKA MINOLTA ADVANCED LAYERS, INC.), one of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer 3 having a width B of 90 μm only on the surface side which was exposed to the outside after sealing with resin, so that an etching resist pattern layer for lead frame having an etching resist pattern for forming a protrusion 4 (dummy pattern for controlling etching rate) was formed. And then, the metal substrate 1 having been provided with the etching resist pattern layer that had the patterns for forming protrusion was given an etching process. As a result, the etching resist layers 3 for forming protrusion, which were given on the both surfaces of the metal substrate 1 and each of which had the width B of 90 μm, slowed down progress of etching for the portion, so that a shape of lead frame which included a protrusion 4 having a width E of 10 μm (an amount of the protrusion projecting from the edge of the upper surface in the horizontal direction), a height G of 90 μm (an amount of the protrusion projecting from the upper surface in the downward direction), and a thickness F of 50 μm was formed. Afterward, the etching resist layers were removed from the metal substrate, so that a band-shaped copper lead frame was obtained (refer to FIGS. 6 and 7 ). The width of the protrusion 4 in the embodiment 2 was narrower than that of the protrusion 4 in the embodiment 1 but the protrusion 4 in the embodiment 2 was finished so that the height of the protrusion 4 in the embodiment 2 was approximately equal to that of the protrusion 4 in the embodiment 1. In this case, an opening between the etching resist pattern layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width D of 95 μm. Afterward, the etching resist pattern layers were peeled off, the band-shaped lead frame was plated with metal as it was, to have extremely thin metal layers. Afterward, the band-shaped lead frame was cut off into fine pieces along its transverse direction, and then resin tapes for fixing sealing resin were stuck on these fine pieces respectively, to obtain finished lead frame sheets.
Embodiment 3
A band-shaped cupper material (KLF-194: made by Kobe Steel, Ltd.) having a thickness of 0.2 mm and a width of 180 mm was used as a metal substrate 1 for lead frame, and photo sensitive resist layers (negative-type photo sensitive resist AQ-2058: made by Asahi Kasei E-materials Corporation.) each having a thickness of 20 μm were formed on the both surfaces of this metal substrate 1 respectively. And then, in order to form a protrusion 4 , the both surfaces of the metal substrate 1 that were given the photo sensitive resist layers respectively were exposed to be developed through glass masks (HY2-50P: made by KONIKA MINOLTA ADVANCED LAYERS, INC.), one of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer having a width A of 55 μm on the packaging-surface side and the other of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer having a width B of 100 μm on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ), so that etching resist pattern layers for lead frame each having an etching resist pattern for forming a protrusion 4 (dummy pattern for controlling etching rate) were formed. And then, the metal substrate 1 having been provided with the etching resist pattern layers that had the patterns for forming protrusion was given an etching process. As a result, the extremely thin etching resist layers 3 for forming protrusion which were given on the both surfaces of the metal substrate 1 slowed down progress of etching for the portion, so that a shape of lead frame which included a protrusion 4 having a width E of 30 μm (an amount of the protrusion projecting from the edge of the upper surface in the horizontal direction), a height G of 150 μm (an amount of the protrusion projecting from the upper surface in the downward direction), and a thickness F of 50 μm was formed. Afterward, the etching resist layers were peeled off, so that a band-shaped copper lead frame was obtained (refer to FIGS. 4 and 8 ). In this case, an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width C of 30 μm on the packaging-surface side, and an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width D of 115 μm on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ). Afterward, the band-shaped lead frame was plated with metal as it was, to have extremely thin metal layers. Afterward, the etching resist pattern layers were peeled off, and the band-shaped lead frame was cut off into fine pieces along its transverse direction, and then resin tapes for fixing sealing resin were stuck on these fine pieces respectively, to obtain finished lead frame sheets.
Embodiment 4
A band-shaped cupper material (KLF-194: made by Kobe Steel, Ltd.) having a thickness of 0.2 mm and a width of 180 mm was used as a metal substrate 1 for lead frame, and photo sensitive resist layers (negative-type photo sensitive resist AQ-2058: made by Asahi Kasei E-materials Corporation.) each having a thickness of 20 μm were formed on the both surfaces of this metal substrate 1 respectively. And then, in order to form a protrusion 4 , the both surfaces of the metal substrate 1 that were given the photo sensitive resist layers respectively were exposed to be developed through glass masks (HY2-50P: made by KONIKA MINOLTA ADVANCED LAYERS, INC.), one of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer having a width A of 40 μm (dummy pattern for controlling etching rate) on the packaging-surface side and the other of the glass masks having been given a design for lead frame which included a pattern for forming an etching resist pattern layer having a width B of 80 μm (dummy pattern for controlling etching rate) on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ), so that etching resist pattern layers for lead frame each having an etching resist pattern for forming a protrusion 4 were formed. And then, the metal substrate 1 having been provided with the etching resist pattern layers that had the patterns for forming protrusion was given an etching process. As a result, the extremely thin etching resist layers 3 for forming protrusion which were given on the both surfaces of the metal substrate 1 slowed down progress of etching for the portion, so that a shape of lead frame which included a protrusion 4 having a width E of 70 μm (an amount of the protrusion projecting from the edge of the upper surface in the horizontal direction), a height G of 100 μm (an amount of the protrusion projecting from the upper surface in the downward direction), and a thickness F of 50 μm was formed (refer to the central part of the list shown in FIG. 5 ). Afterward, the etching resist pattern layers were not removed from the metal substrate to be kept on the metal substrate. In this case, an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width C of 40 μm on the packaging-surface side, and an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width D of 120 μm on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ). Afterward, portions of the surface of the band-shaped lead frame which were not covered with the etching resist pattern layers and which included protrusions were roughened with a roughening solution of an organic acid system or a hydrogen peroxide-sulfic acid system so that the portions of the surface of band-shaped lead frame which were not covered with the etching resist pattern layers had a roughness average (Ra) of 0.12 to 0.2 μm, with the etching resist pattern layers not removed from the band-shaped lead frame, to obtain the lead frame having more improved adhesiveness of resin to the lead frame (refer to FIGS. 9 and 10 ). Afterward, the etching resist pattern layers were peeled off, and the band-shaped lead frame was plated with metal as it was, to have extremely thin metal layers. Afterward, the band-shaped lead frame was cut off into fine pieces along its transverse direction, and then resin tapes for fixing sealing resin were stuck on these fine pieces respectively, to obtain finished lead frame sheets.
Embodiment 5
A band-shaped cupper material (KLF-194: made by Kobe Steel, Ltd.) having a thickness of 0.2 mm and a width of 180 mm was used as a metal substrate 1 for lead frame, and photo sensitive resist layers (negative-type photo sensitive resist AQ-2058: made by Asahi Kasei E-materials Corporation.) each having a thickness of 20 μm were formed on the both surfaces of this metal substrate respectively. And, glass masks each having a pattern for plating parts of a lead frame were covered with the front and back surfaces of the metal substrate 1 respectively, with the patterns of the glass masks properly positioned respectively, and then the both surfaces of the metal substrate 1 were exposed to ultraviolet rays through the glass masks. After the exposure to ultraviolet rays, the glass masks were removed from the metal substrate 1 , and then the metal substrate with the light sensitive resist layers was immersed in a developer so that the photo sensitive resist layers were developed. As a result, only portions of the photo sensitive resist layers which had been not exposed to ultraviolet rays, or only portions of the photo sensitive resist layers corresponding to portions which were plated to be a semiconductor-mounting part, a terminal part or the like, were removed from the metal substrate, so that plating resist layers were obtained. Next, the metal substrate with the plating resist layers was put in a plating tank so that the metal portions of the metal substrate which were exposed to the outside were plated with Ag to be given Ag-plating layers having a thickness of 3 μm. Afterward, the plating resist layers were removed from the metal substrate, so that a metal substrate with plating layers was obtained. Besides, in this case, types of plating metals are not limited to the above-described metals, and every type of metals generally applicable to lead frames such as Ni/Pd/Au may be used for the present invention, and, in addition, every composition of plating may be used for the present invention. Next, a photo sensitive resist layers was formed on the whole of each of the front and back surfaces of the metal substrate again. And then, in order to form a protrusion 4 , the both surfaces of the metal substrate 1 that were given the photo sensitive resist layers respectively were exposed to be developed through glass masks (HY2-50P: made by KONIKA MINOLTA ADVANCED LAYERS, INC.), one of the glass masks having had a pattern for forming an etching resist pattern layer having a width A of 40 μm (dummy pattern for controlling etching rate) on the packaging-surface side and the other of the glass masks having had a pattern for forming an etching resist pattern layer having a width B of 80 μm (dummy pattern for controlling etching rate) on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ) and these glass masks having been capable of forming the etching resist pattern layers for lead frame each of which had an outer shape larger than those of the above plating areas by 50 μm so as to be capable of wholly covering the plating areas, so that etching resist pattern layers for lead frame each having an etching resist pattern for forming a protrusion 4 were formed. And then, the extremely thin etching resist layers 3 for forming protrusion slowed down progress of etching for the portion, so that a lead frame which included a protrusion 4 having a width E of 70 μm (an amount of the protrusion projecting from the edge of the upper surface in the horizontal direction), a height G of 100 μm (an amount of the protrusion projecting from the upper surface in the downward direction), and a thickness F of 50 μm was formed (refer to the central part of the list shown in FIG. 5 ). In this case, an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width C of 40 μm on the packaging-surface side, and an opening between the etching resist layer 2 for forming lead frame and the etching resist layer 3 for forming the protrusion 4 was formed to have a width D of 120 μm on the other-surface side which was exposed to the outside after sealing with resin (refer to FIG. 4 ). Also, in forming protrusions by etching in forming the lead frame, the etching resist pattern layers were removed from the metal substrate after the etching. In addition, portions of the surface of the band-shaped lead frame which were not covered with the etching resist pattern layers and which included protrusions were roughened with a roughening solution of an organic acid system or a hydrogen peroxide-sulfic acid system so that the portions of the surface of band-shaped lead frame which were not covered with the etching resist pattern layers had a roughness average (Ra) of 0.12 to 0.2 μm, with the etching resist pattern layers not removed from the band-shaped lead frame (refer to FIGS. 9 and 10 ), and afterward, the etching resist pattern layers were peeled off. As a result, a lead frame which included a lateral-side protrusion for mold-lock and the surfaces of which were rough surfaces with improved adhesiveness to resin was obtained.
Comparative Example
A band-shaped cupper material (KLF-194: made by Kobe Steel, Ltd.) having a thickness of 0.2 mm and a width of 180 mm was used as a metal substrate 1 for lead frame, and photo sensitive resist layers (negative-type photo sensitive resist AQ-2058: made by Asahi Kasei E-materials Corporation.) each having a thickness of 20 μm were formed on the both surfaces of this metal substrate respectively. And then, in order to form a protrusion 4 , the both surfaces of the metal substrate 1 that were given the photo sensitive resist layers respectively were exposed to be developed through a glass mask for etching resist pattern for lead frame (HY2-50P: made by KONIKA MINOLTA ADVANCED LAYERS, INC.), the glass mask having had a pattern for forming an etching resist pattern layer having a width B of 110 μm only on the surface side which was exposed after sealing with resin (refer to FIG. 6 ), so that etching resist pattern layers for lead frame were formed. And then, the metal substrate 1 having been provided with the etching resist pattern layers was given an etching process. As a result, the extremely thin etching resist layer 3 for forming protrusion which was given on the surface side that was exposed to the outside after sealing with resin slowed down progress of etching for the portion, so that a lead frame which included a protrusion 4 was made. In this case, an opening between the etching resist layer 2 for forming lead frame and the resist layer 3 for forming the protrusion 4 was formed to have a width D of 125 μm (refer to FIG. 6 ). However, the thickness of the formed protrusion 4 was 15 μm and thin. Also, the protrusion partially deformed or a part of the protrusion disappeared, and, in addition, the shape of the top end of the protrusion was sharp. Accordingly, there was a large possibility that the shape of the top end of the protrusion in the comparative example caused deficiency of adhesiveness to the lead frame after sealing with resin or became a starting point of a crack in resin (refer to FIG. 2 ). | A lead frame for mounting semiconductor element includes a protrusion that is horizontally projects from edges of the upper and lower surfaces of a semiconductor-mounting part or a terminal part of the lead frame and that is provided on a lateral side of at least one of the semiconductor-mounting part or the terminal part of the lead frame, wherein the top end of the protrusion is substantially flat or the profile of the cross section of the top end is arc-shaped, and the top end of the protrusion is thick. | 7 |
RELATED APPLICATIONS
[0001] The subject invention has widespread utility as illustrated in the co-pending application Ser. No. 11/040,989 (DP-312789); Ser. No. 11/040,321 (DP-311408) and Ser. No. 11/040,988 (DP-311409), all filed on Jan. 21, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] A fluid heat exchanger unit for cooling an electronic device.
[0004] 2. Description of the Prior Art
[0005] Research activities have focused on developing assemblies to efficiently dissipate heat from electronic devices that are highly concentrated heat sources, such as microprocessors and computer chips. These electronic devices typically have power densities in the range of about 5 to 35 W/cm 2 and relatively small available space for placement of fans, heat exchangers, heat sink assemblies and the like. However, these electronic devices are increasingly being miniaturized and designed to achieve increased computing speeds that generate heat up to 200 W/cm 2 .
[0006] Heat exchangers and heat sink assemblies have been used that apply natural or forced convection cooling methods to cool the electronic devices. These heat exchangers typically use air to directly remove heat from the electronic devices. However, air has a relatively low heat capacity. Such heat sink assemblies are suitable for removing heat from relatively low power heat sources with power density in the range of 5 to 15 W/cm 2 . The increased computing speeds result in corresponding increases in the power density of the electronic devices in the order of 20 to 35 W/cm 2 thus requiring more effective heat sink assemblies.
[0007] In response to the increased heat to be dissipated, liquid-cooled units called LCUs employing a cold plate in conjunction with high heat capacity fluids, like water and water-glycol solutions, have been used to remove heat from these types of high power density heat sources. One type of LCU circulates the cooling liquid so that the liquid removes heat from the heat source, like a computer chip, affixed to the cold plate, and is then transferred to a remote location where the heat is easily dissipated into a flowing air stream with the use of a liquid-to-air heat exchanger and an air moving device such as a fan or a blower. These types of LCUs are characterized as indirect cooling units since they remove heat from the heat source indirectly by a secondary working fluid, generally a single-phase liquid, which first removes heat from the heat source and then dissipates it into the air stream flowing through the remotely located liquid-to-air heat exchanger. Such LCUs are satisfactory for moderate heat flux less than 35 to 45 W/cm 2 at the cold plate.
[0008] In the prior art heat sinks, such as those disclosed in U.S. Pat. Nos. 6,422,307 and 5,304,846, the single-phase working fluid of the liquid cooled unit (LCU) flows directly over the cold plate causing cold plate corrosion and leakage problems.
[0009] As computing speeds continue to increase even more dramatically, the corresponding power densities of the devices rise up to 200 W/cm 2 . The constraints of the miniaturization coupled with high heat flux generated by such devices call for extremely efficient, compact, and reliable thermosiphon cooling units called TCUs. Such TCUs perform better than LCUs above 45 W/cm 2 heat flux at the cold plate. A typical TCU absorbs heat generated by the electronic device by vaporizing the captive working fluid on a boiler plate of the unit. The boiling of the working fluid constitutes a phase change from liquid-to-vapor state and as such the working fluid of the TCU is considered to be a two-phase fluid. The vapor generated during boiling of the working fluid is then transferred to an air-cooled condenser, in close proximity to the boiler plate, where it is liquefied by the process of film condensation over the condensing surface of the TCU. The heat is rejected into an air stream flowing over a finned external surface of the condenser. The condensed liquid is returned back to the boiler plate by gravity to continue the boiling-condensing cycle.
[0010] The aforementioned co-pending applications disclose a cooling housing with a partition dividing the cooling housing into a upper portion having an upper wall, with a liquid coolant inlet for receiving liquid coolant from the system and a liquid coolant outlet, and a lower portion. The upper portion defines a coolant passage between the partition and the upper wall for liquid coolant flow from the liquid coolant inlet to the liquid coolant outlet. A refrigerant is disposed in the lower portion of the cooling housing for liquid-to-vapor transformation. An electronic device generates an amount of heat to be dissipated and the heat is transferred from the electronic device to the bottom of the heat exchanger cooling housing. The heat is then conducted from the bottom to the refrigerant in the lower portion. A working fluid mover, such as a pump, moves a coolant liquid through a cooling fluid storage vessel that stores excess coolant. The pump moves the cooling fluid through a heat extractor or radiator to dissipate heat from the coolant. However, in that system the radiator is separate and spaced remotely from the cooling housing, to thereby require separate manufacturing, shipping, handling and installation.
SUMMARY OF THE INVENTION AND ADVANTAGES
[0011] In accordance with the subject invention, heat generated by an electronic device is also transferred to the lower portion of such a cooling housing having a refrigerant therein for liquid-to-vapor transformation as liquid coolant flows above a partition defining a coolant passage in the upper portion of the cooling housing. In addition, a heat rejecter is disposed on and above the upper wall of the cooling housing with a rejecter inlet adjacent and in fluid communication with the liquid coolant outlet of the cooling housing and a rejecter outlet adjacent the liquid coolant inlet of the cooling housing for returning liquid coolant to the system.
[0012] The present invention utilizes a single unit to define both the cooling housing and the air cooled heat rejecter to thereby allow the manufacture of the unit in a single process with the attendant reduction in shipping, handling and installation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
[0014] FIG. 1 is schematic view of the system with the cooling housing and the air cooled radiator being completely separate;
[0015] FIG. 2 is perspective view of the unit of the subject invention;
[0016] FIG. 3 is an exploded perspective view, partially cut away;
[0017] FIG. 4 is a cross sectional view of the unit shown in FIG. 2 ;
[0018] FIG. 5 is another embodiment of the unit of the subject invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] As alluded to above, the fluid heat exchanger unit of the subject invention incorporates a cooling housing 20 of the type disclosed in the aforementioned co-pending patent applications. The cooling housing 20 includes a liquid coolant inlet 22 and a liquid coolant outlet 24 and an upper portion 26 defining a top or upper wall 27 and a lower portion 28 extending between the liquid coolant inlet 22 and the liquid coolant outlet 24 for establishing a direction of flow from the liquid coolant inlet 22 to the liquid coolant outlet 24 . The cooling housing 20 is used to cool an electronic device 30 engaging or secured to the lower portion 28 of the cooling housing 20 . The electronic device 30 or component is preferably adhesively secured in a recess 29 in the bottom 40 of the cooling housing 20 .
[0020] A partition 32 divides the cooling housing 20 into the upper portion 26 and the lower portion 28 for establishing a direction of flow of liquid coolant in a coolant passage 33 defined between the upper wall 27 and the partition 32 from the liquid coolant inlet 22 to the liquid coolant outlet 24 in the upper portion 26 . The cooling housing 20 is hermetically sealed about the partition 32 to contain a refrigerant in the lower portion 28 for liquid-to-vapor transformation. In other words, the partition 32 separates the refrigerant in the lower portion 28 from the liquid coolant in the coolant passage 33 of the upper portion 26 .
[0021] The partition 32 and the upper wall 27 are undulated or corrugated transversely to the direction of flow from the liquid coolant inlet 22 to the liquid coolant outlet 24 to define the flow passage. The partition 32 defines a lower wall of the coolant passage 33 in the upper portion 26 and the upper wall 27 of the upper portion 26 defines a top of the coolant passage 33 , which top or upper wall 27 is also undulated transversely to the direction of flow from the liquid coolant inlet 22 to the liquid coolant outlet 24 to define the coolant passage 33 . Disposed inside the coolant passage 33 are the flow interrupters 34 extending vertically upward into the coolant stream. The purpose of the flow interrupters 34 is to interrupt the thermal boundary layer growing from the upper corrugated wall and the lower corrugated wall of the coolant passage 33 . The interruption of the thermal boundary layer causes the heat transfer coefficient to attain a higher value at the point of interruption.
[0022] A plurality of fins 36 extend from the bottom 40 of the cooling housing 20 for increasing heat transfer from the electronic device 30 to the interior of the lower portion 28 of the cooling housing 20 . The fins 36 extend linearly across the direction of flow under the partition 32 and between the liquid coolant inlet 22 and the liquid coolant outlet 24 in the upper portion 26 . The heat transfer fins 36 are disposed in the lower portion 28 of the cooling housing 20 for transferring heat from the electronic device 30 disposed on the exterior of the lower portion 28 of the cooling housing 20 . The fins 36 vary in height and, more specifically, the fins 36 are of the greatest height midway between the liquid coolant inlet 22 and the liquid coolant outlet 24 and are of progressively lesser height from the midpoint toward the liquid coolant inlet 22 and the liquid coolant outlet 24 respectively. The middle fin 36 may extend all the way to the lower corrugated wall and be brazed to it to provide reinforcement to the vapor chamber below the lower corrugated wall.
[0023] The upper portion 26 of the cooling housing 20 presents a generally rectangular footprint and the lower portion 28 of the cooling housing 20 is coextensive with the upper portion 26 . The entire cooling housing 20 , including the flow passage with upper corrugated wall and lower corrugated wall along with end sections, and the pan-shaped lower portion 28 having integrally formed therewith the fins 36 and the recess 29 for the electronic device 30 , may be extruded as a single or integral piece thereby obviating the need for various brazing operations. Sections of the extrusion are cut and end sheets with braze coating are stamped out of sheet stock and bonded to the edges of the extruded sections, thereby hermetically sealing the upper portion 26 and lower portions 28 of the cooling housing 20 .
[0024] In addition, the spaces between the undulations of the upper wall 27 may be filled in with the metal material of the upper wall 27 or filler material 38 for providing a flat surface for banding to the first fins 54 .
[0025] The upper portion 26 of the housing 20 is generally rectangular and the lower portion 28 of the housing 20 is generally rectangular and generally coextensive with the upper portion 26 . A recess 29 extends into the lower portion 28 of the housing 20 for receiving the electronic device 30 . The entire housing 20 , including the flow passage with upper corrugated wall and lower corrugated wall along with end sections defining a gallery 42 or tank 42 , and the pan-shaped lower portion 28 having integrally formed therewith the fins 36 and the recess 29 for the electronic device 30 , may be extruded as a single or integral piece thereby obviating the need for various brazing operations. Sections of the extrusion are cut and end plates 44 with braze coating are stamped out of sheet stock. During the stamping of the end plates 44 , various grooves are formed in the end plates 44 to receive and facilitate bonding to the edges of the extruded sections, thereby hermetically sealing the upper portion 26 and lower portions 28 of the housing 20 . A simple machining operation is used to drill holes in one end plate 44 and in the gallery 42 or tank 42 that feeds the coolant passage 33 . A refrigerant charge tube 46 is welded to the hole drilled in the end plate 44 , and the tubular coolant is welded to the gallery 42 or tank 42 .
[0026] The liquid cooling system illustrated in FIG. 1 incorporates the heat exchanger cooling housing 20 for cooling an electronic device 30 . As alluded to above, a working fluid mover, such as a pump P, moves a cooling fluid, usually a liquid, through a cooling fluid storage vessel T, that stores excess cooling fluid. The pump P moves the cooling fluid through a heat extractor or radiator unit to dissipate heat from the cooling fluid, the heat extractor or radiator unit including a fan F and radiator R. The radiator R is separate and spaced from the cooling housing 20 .
[0027] In accordance with the subject invention, a heat rejecter 48 is integrally fabricated with the cooling housing 20 whereby liquid coolant flows directly out of the coolant outlet 24 of the cooling housing 20 and into an air cooled heat rejecter 48 . The heat rejecter 48 is disposed on and above the upper wall 27 of the cooling housing 20 with a rejecter inlet 50 adjacent and in fluid communication with the liquid coolant outlet 24 and a gallery 42 or a rejecter outlet 52 adjacent the liquid coolant inlet 22 for returning liquid coolant to the system.
[0028] The heat rejecter 48 includes at least one layer of first air fins 54 and at least one layer of first tubes 56 for conducting liquid coolant from the rejecter inlet 50 to the rejecter outlet 52 for transferring heat from the first tubes 56 to the first air fins 54 . The plurality of first air fins 54 are disposed along the filler material 38 and upper wall 27 to extend between the rejecter inlet 50 and the rejecter outlet 52 . To facilitate the first tubes 56 , the heat rejecter 48 includes a first header 58 extending from the rejecter inlet 50 in a direction transverse to the upper wall 27 and a second header 60 extending from the rejecter outlet 52 in a direction transverse to the upper wall 27 . The first header 58 is defined by a pair of parallel and spaced walls formed integrally with the upper wall 27 of the cooling housing 20 and the bottom 40 wall of the lower portion 26 , 28 and/or the partition 32 . Likewise, the second header 60 is defined by a pair of parallel and spaced walls extending upwardly from the rejecter outlet 52 or gallery 42 . Although there are normally a plurality of laterally spaced first tubes 56 , at least one first tube 56 extends between and in fluid communication with the first header 58 and the second header 60 with the first air fins 54 disposed between the upper wall 27 and the first tube 56 or first tubes 56 . As illustrated in FIGS. 4 and 5 , the rejecter would frequently include a plurality of second air fins 62 disposed above the first tube 56 and at least one second tube 64 is disposed above the second air fins 62 and extends between and in fluid communication with the first header 58 and the second header 60 .
[0029] The heat rejecter 48 includes a tunnel-shaped casing 66 extending from the liquid coolant inlet 22 upwardly with the second header 60 and across the unit and downwardly with the first header 58 to the liquid coolant outlet 24 . The casing 66 and the first air fins 54 and the second air fins 62 extend parallel to one another for air to pass through the casing 66 and the first air fins 54 and the second air fins 62 in a direction transverse to the first tubes 56 and the second tubes 64 . The casing 66 is an inverted U-shape with the legs secured to the cooling housing 20 . A plurality of third air fins 68 are disposed between and parallel to the casing 66 and the first header 58 and are disposed between and parallel to the casing 66 and the second header 60 and extend across the unit between the first header 58 and the second header 60 . In other words, the third air fins 68 extend through the same U-shaped path of the casing 66 .
[0030] Although as shown, the second header 60 includes a separate passage for each of the first tube 56 and the second tube 64 , either one of the first header 58 and the second header 60 may include a separate passage for each of the first tube 56 and the second tube 64 , as illustrated in FIG. 4 .
[0031] The end plates 44 include header plates 70 integral with the end plates 44 and extending upwardly to close and seal the open sides of the first header 58 and the second header 60 . All of the components may be made of metal and wired together and placed in a brazing furnace.
[0032] The liquid coolant inlet 22 to the cooling housing 20 is disposed above the rejecter outlet 52 . The liquid coolant inlet 22 to the cooling housing 20 feeds an inlet gallery 42 and is defined by a tubular liquid coolant inlet 22 . A tubular outlet 72 empties the rejecter outlet 52 . Both tubular members are also brazed into position in spaced and parallel relationship to one another. The rejecter outlet 52 defines an outlet gallery 42 joined to the inlet gallery 42 , as by sharing a common wall.
[0033] The electronic device 30 generates heat that is transferred through the fins 36 to the captive refrigerant sealed in the lower portion 28 of the cooling housing 20 to boil and vaporize the refrigerant. The vaporized refrigerant rises in the lower portion 28 of the cooling housing 20 and into the V-shaped cavities between the crests of the coolant flow passage. The liquid coolant flowing through the undulating coolant passage 33 absorbs heat from the refrigerant vapor thereby condensing the vapor back into liquid refrigerant pooled in the lower portion 28 where it again absorbs heat from the electronic device 30 to repeat the cycle. At the same time, liquid coolant exits the cooling housing 20 and immediately into the first header 58 for distribution to the first tubes 56 , and likely second tubes 64 , whereby the liquid coolant is further cooled by heat transfer with the fist fins 36 , and likely the second fins 36 . The liquid coolant then flows into the rejecter outlet 52 gallery 42 for return to the system. The third fins 36 further enhance the heat transfer, particulary with the first header 58 and the second header 60 .
[0034] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. The invention may be practiced otherwise than as specifically described within the scope of the appended claims, wherein recitations should be interpreted to cover any combination in which the incentive novelty exercises its utility. | A fluid heat exchanger unit cools an electronic device with a cooling fluid supplied to an upper portion of a cooling housing. A refrigerant is disposed in a lower portion of the cooling housing for liquid-to-vapor transformation. A partition divides the upper portion of the cooling housing from the lower portion. A heat rejecter is disposed on and above the upper wall of the cooling housing with a first header extending from and in fluid communication with the liquid coolant outlet. A second header extends upwardly from a rejecter outlet. A plurality of first tubes extend between and in fluid communication with the first header and the second header with a plurality of first air fins disposed between the upper wall and the first tubes. A single unit defines both the cooling housing and the air cooled heat rejecter to thereby allow the manufacture of the unit in a single process with the attendant reduction in shipping, handling and installation. | 5 |
[0001] This application claims the benefit under 35 U.S.C. 119 ( e ) of U.S. Provisional Application No. 60/468,185, filed May 6, 2003.
FIELD OF THE INVENTION
[0002] This invention relates to display devices and particularly to flame simulating devices.
BACKGROUND OF THE INVENTION
[0003] Conventional flame sources require lighting with matches or the like, and when lit, represent a serious fire hazard, especially when unattended as is the case in commercial settings (e.g. restaurants, stores etc.) Furthermore, real flame sources (e.g. candles) present other personal injury and collateral damage challenges (e.g. dripping wax on people and/or upholstery etc.) Finally, real flame sources are easily extinguished (e.g. by air currents etc.) and accordingly cannot be easily setup and maintained without constant monitoring.
[0004] There are a variety of flame imitation novelty products that utilize various methods to simulate a real flame for display purposes such as those disclosed in U.S. Pat. Nos. 6,454,425 and 4,550,363. Specifically, U.S. Pat. No. 6,454,425 discloses a candle flame simulating device that includes a blowing device for generating an air and for directing the air toward a flame-like flexible member, in order to blow and to oscillate or to vibrate the flame-like flexible member and to simulate a candle. U.S. Pat. No. 4,550,363 discloses an electric-light bulb fitted with a light permeable and light-scatting lamp casing. However, such attempts result in flame displays that are relatively poor imitations of a real flame. In addition, such devices require substantial energy and require frequent battery replacement.
SUMMARY OF THE INVENTION
[0005] The invention provides in one aspect, a flame simulating device comprising:
[0006] (a) a substantially translucent shell having a hollow interior and a directional axis;
[0007] (b) a plurality of colored light sources, adapted to be positioned within the hollow interior of said shell;
[0008] (c) a light source driving device for selectively activating each of said plurality of light sources;
[0009] (d) each of said light sources being selectively activated such that the surface of said shell is illuminated and produces an animated flame effect.
[0010] Further aspects and advantages of the invention will appear from the following description taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In the accompanying drawings:
[0012] [0012]FIG. 1 is a cross-sectional view of the flame simulating device of the present invention;
[0013] [0013]FIG. 2 is a schematic drawing illustrating the duty cycles of the yellow, orange and red light sources of FIG. 1;
[0014] [0014]FIG. 3 is a schematic drawing of an example implementation of LED lighting assembly that drives the LED array of FIG. 1;
[0015] [0015]FIG. 4 is a block diagram of an example implementation of control circuit of FIG. 3;
[0016] [0016]FIG. 5 is a flow-chart illustrating the main steps of the MAIN OPERATION routine utilized by the microcontroller to control the output of the LED array of FIG. 4; and
[0017] [0017]FIG. 6 is a schematic drawing of an example implementation of an audio deactivator device that shuts off the light source driving circuit of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Referring to FIG. 1, illustrated therein is a flame simulating device 10 made in accordance with a preferred embodiment of the present invention. Flame simulating device 10 consists of an LED lighting assembly 30 that is incased in a substantially translucent shell 40 . LED assembly 30 consists of an LED array 12 , a power source 16 , light source driving circuit 18 . Light source driving circuit 18 is designed to allow a maximum of one LED from LED array 12 to be on at any particular time. Also as shown, flame simulating device 10 is also adapted to fit within the top of a base 41 . The combination of LED assembly 30 and shell 40 of flame simulating device 10 provides realistic flame lighting effects as will be described.
[0019] Shell 40 is substantially translucent in order to allow a substantial amount of light from LED array 12 to penetrate the surface of shell 40 such that visible lighting effects are provided on the surface of shell 40 . Shell 40 is preferably flame-shaped (FIG. 1) but it should be understood that shell 40 could be any volumetric container that has enough space within to house LED lighting assembly 30 . For example, it is contemplated that shell 40 could have the shape of a pen-shaped tubular body, a spherical ball, a rectangular box, a multisided box, etc. (e.g. adapted to be coupled to a keychain etc.) for application to various novelty items. Other example include yo-yo's, batons, computer mice, lamps, bulbs, night lights, wearable items (e.g. necklaces, broaches, pins, hair accessories, lariats), floral “picks” (longitudinal bodies for use with floral bouquets), picture frames, gearshift knobs and tire lights to only name a few. Finally, while shell 40 is preferably manufactured from plastic, it should be understood that it could be manufactured from other materials.
[0020] As illustrated in FIG. 1, LED array 12 comprises a plurality of LEDs. In order to provide realistic flame effects, it has been determined that it is optimal to use at least one yellow, at least one orange, and at least one red LED within LED array 12 . However, it should be understood that it is also possible to use various color types and combination of LEDs within LED array 12 (e.g. the additional use of white LEDs to add brightness to the array, the additional use of blue LEDs to simulate propane gas flame etc.)
[0021] For illustrative purposes, the present invention will be described in respect of a LED array 12 that comprises one yellow LED 12 a , one orange LED 12 b , and one red LED 12 c as shown in FIG. 1. Also for discussion purposes, it should be noted that yellow, orange and red LEDs 12 a , 12 b and 12 c are arranged at different heights as measured along the longitudinal axis of flame-shaped shell 40 (FIG. 1). This variation in directional axis (i.e. the longitudinal axis of this example embodiment) further enhances the “flame-like” effect produced by flame simulation device 10 since the different colored LEDs are positioned to represent different parts of a flame.
[0022] As conventionally known, LEDs are semiconductor devices that emit a visible light when current biased in the forward direction. Unlike standard bulb type lamps, LEDs are immune to failure conditions such as filament breakage due to sudden shocks or bumps and are well suited for use in articles that may experience sudden impacts from being bounced or shaken such as flame simulating device 10 . In addition, LEDs are highly energy efficient as they only require a small amount of electricity to generate a relatively strong light. For example, a typical incandescent lamp operates on 5 volts and uses a current of 115 milliamps while a LED can operate on 3 volts and draw current on the order of 5 to 20 milliamps.
[0023] Accordingly, LEDs are a particularly desirable lighting source in applications involving small and lightweight devices where the desired size and weight limits the strength of power sources available thereby making energy efficiency important. The LEDs of LED array 12 are preferably 5 mm high intensity wide dispersion color LEDs. However, it should be understood that many other kinds of LEDs could be utilized depending on the particular visual effect desired or the device production economy required, such as 3 mm on surface mounted lens less LEDs. Since the rated lifetime of these LEDs is approximately 15 years, LED array 12 provides flame simulating device 10 with an energy efficient, long lasting, light weight and durable light source.
[0024] Power source 16 is preferably four conventional penlight “AAA” batteries, consisting of two sets in parallel to insure relatively long life. Alternatively, a 6 volt DC adaptor can be used to power a “screw in” bulb version. Power wires 17 are used to connect LED array 12 to power source 16 . It has been determined that four penlight “AAA” batteries will run flame simulating device 10 continually for over several months. This long lifetime is due to the fact that light source driving circuit 18 is designed to only allow maximum one LED from LED array 12 to be on at any particular time as will be further discussed. This results in substantial power savings since power source 16 is only required to power at a maximum one LED at any particular time. The power requirements of flame simulating device 10 is substantially less than those of devices that use multiple LEDs where one or more LEDs must be powered at any particular time (i.e. simultaneously).
[0025] Now referring to FIGS. 1 and 2, FIG. 2 illustrates an example activation protocol for the three example LEDs within LED array 12 that have been discussed. It should be understood that many different types of activation profiles and relative positioning of activation characteristics for the various LEDs could be used for the LEDs within LED array 12 of flame simulating device 10 . As discussed, generally speaking yellow, orange and red LEDs 12 a , 12 b and 12 c are sequentially activated and deactivated in a manner that simulates the color flickering of a real flame. Specifically, yellow, orange and red LEDs 12 a , 12 b and 12 c are sequentially activated according to a set of color transition rules as will be discussed in more detail below.
[0026] The activation characteristics of LEDs within LED array 12 shown in FIG. 2 are represented as follows. For each LED 12 a , 12 b and 12 c , a high level line is used to indicate that an LED is “active” and a low level line is used to indicate that an LED is “inactive”. The LEDs within LED array 12 are activated for periods of time such that the human eye perceives the alternate color of each of said yellow, orange and red LED (i.e. long enough activation periods). At the same time, the user sees the color of a particular LED briefly enough so that the “look” of a flame is produced with the requisite flicker and change of color inherent in a real flame.
[0027] By doing so, it is possible to achieve a realistic color transition effect on shell 40 as the human eye will perceive the resulting visual display from LED array 12 on shell 40 as being mix of color with moving yellow, orange and red hues. In addition the human eye will perceive that at times, more than one LED is “active” due to the well-known after image that the eye sees even after an LED is already off. Accordingly, unlike the conventional flame bulbs that simply light up or have two wire filaments that are used to cause a twinkling effect, this LED-based flame source will appear to flicker much more like a real flame.
[0028] Also, while it is not explicitly shown on the activation characteristics in FIG. 2, each “active” period for a particular LED preferably represents the turning on and off of the LED at a suitable high frequency rate (e.g. 160 times per second per “active” period). It should be understood that it is possible to operate LED assembly 12 during “active” periods without turning on and off (i.e. a steady on for the extent of the “active” period) although power requirements will be higher. The specific high frequency utilized for turning the LED on and off during the “activation” period is selected such that the rapid blinking of an individual LED is not perceptible to the human eye. In practical terms, the LEDs of LED array 12 will be inactive for up to approximately 80% of the time, resulting in substantial power savings and long life for a fixed battery power source 16 . As discussed previously, a typical LED can operate on 3 volts and draw current on the order of 5 to 20 milliamps. However, since the LEDs within LED array 12 are inactive up to 80% of the time, the current draw of LED array 12 is greatly reduced and has been determined to be as low as 5 mA per LED
[0029] In this particular example, light source driving circuit 18 sequentially activates LEDs 12 a , 12 b and 12 c . As shown, the following activation cycle is executed: red (12aON1), orange (12bON2), yellow (12cON3), orange (12bON4), yellow (12cON5), orange (12bON6), red (12aON7), orange (12bON8), yellow (12cON9) etc. It has been determined that it is beneficial to cycle between yellow and orange, between orange and red, but not between red and yellow, in order to minimize the “color” transition difference. Further, since LED array 12 is encased in a translucent shell 40 , the LED colors will mix and blend providing an impression that the shell 40 “glows” much like a true flame glows.
[0030] It has been determined that when using LEDs that emit light at different frequencies (i.e. the frequencies associated with yellow, orange, red etc.), it is preferable to sequentially activate LEDs that emit light at frequencies which are close together in order to minimize the length of the color “steps” (i.e. to minimize the visible difference in color between activated LEDs). Accordingly, the LED lighting sequence steps in the example (i.e. as shown in FIG. 2) follow such transition rules. For example, in the case of the yellow, orange and red LEDs shown in FIG. 2, yellow is never activated before or after red. Rather, since orange is closer in emitted color to yellow and red, activation transitions move between red and orange and between orange and yellow. However, it should be understood, that many other specific lighting sequences could be used.
[0031] [0031]FIG. 3 shows an example implementation of LED lighting assembly 30 . The main component is a light source driving circuit 18 that contains the logic circuitry that controls the output of LED array 12 . Light source driving circuit 18 is most likely a designed chip on board (COB) that can be customized for this application. Light source driving circuit 18 could be adapted to be integrated with the LEDs of LED array 12 to form a single sub-assembly complete with embedded program. The outputs of light source driving circuit 18 are each connected to a separate LED in LED array 12 . LED array 12 itself is connected in series with a load resistor RL that limits the current passing through the LEDs of LED array 12 .
[0032] The preprogrammed sequence controls the output state of the flame simulating device 10 . As discussed above, it is preferred to leave the input unconnected in order to cause the LEDs of LED array 12 to light up in a sequential order. It should be understood that although this exemplary embodiment contains the aforementioned inputs this embodiment is only one example implementation. Other embodiments may contain fewer or greater inputs depending on the specific implementation. Light source driving circuit 18 , its functionality and components are described in greater detail below.
[0033] Now referring to FIGS. 2, 3 and 4 , FIG. 4 illustrates a light source driving circuit 18 in block diagram form. Specifically, light source driving circuit 18 includes a microcontroller 52 , an oscillator 54 , a latch 56 and a driver 58 . Microcontroller 52 is electrically coupled to oscillator 54 , through the SCK line 51 , and to latch 56 , through the RSR line 53 and OFF line 55 . Oscillator 54 is also coupled to the latch 56 through the CK line 57 . In turn, the latch 56 , through information lines 59 , is coupled to the driver 58 which itself is electrically coupled to the LEDs in LED array 12 through output lines 61 .
[0034] Microcontroller 52 determines the output state of the flame simulating device 10 , which could be programmable or off. This unit has three inputs, preprogrammed sequence, S (sleep) and R 2 (resistor 2 ) and three outputs, SK (stop clock), RSR (random or sequential) and OFF. Connecting the S input to Vss causes microcontroller 52 to enable the clock signal and latch 56 by sending the appropriate digital signals over the SCK 51 and OFF 55 lines respectively. The result is that the flame simulating device 10 is activated thereby causing LED array 12 to emit light.
[0035] Flame simulating device 10 continues to function until the unit is turned off, at which point, microcontroller 52 disables the clock signal by sending the appropriate digital signal through the SCK line 51 to oscillator 54 . At this time, microcontroller 52 also disables latch 56 by sending the appropriate digital signal through the OFF line 55 . This causes the output to be disabled and the flame simulating device 10 to shut down. Since the preprogrammed sequence line is unconnected, the LEDs of LED array 12 light up sequentially according to a particular transitional rule (i.e. following a strict color order) as will be further described. Microcontroller 52 sends the appropriate digital signal, through the RSR line 53 to the latch 56 , which in turn generates the appropriate output.
[0036] Oscillator 54 generates the periodic clock signal that is used to control timing within the circuit. The oscillator has two inputs, SCK (stop clock) and R 1 (resistor 1 ), and one output, CK (the clock signal). The clock signal is transmitted to latch 56 along the CK line 57 . The resistor connected to R 1 together with an internal capacitance determines a time constant for the circuit, which in turn determines the period of the clock signal. During normal operation, an appropriate digital signal is received from microcontroller 52 along the SCK line 51 and the clock signal is enabled. When flame simulating device 10 is shut off, microcontroller 52 sends an alternative signal via the SCK line 51 and the CK (clock) signal is disabled.
[0037] While the clock rate of the LED controller can be set at 160 Hz, the actual flash rate of the individual LEDs (i.e. yellow LED 12 a , orange LED 12 b , and red LED 12 c ) can be varied throughout the length of the programmed routine, resulting in a more “flame like” appearance. Individual LED frequencies are set visually and then programmed directly into processor. As discussed before, a maximum of one LED is activated at any given time and even when a LED is activated it is being blinked on and off at a rapid frequency. Even so, a user will not perceive that there are any times when all LEDs are inactive (when in fact up to 80% of the time there will be no activated LEDs). As discussed above, since a maximum of one LED is activated at any given time (i.e. there are times at which all LEDs are inactive for short bursts of time), it is possible to run flame simulating device 10 on a set (i.e. finite such as a battery) power supply 16 for a relatively long time. Specifically, it is possible to run flame simulating device 10 for longer than a device which requires at least one LED to be powered at a given time.
[0038] Latch 56 contains the logic circuitry used to generate the appropriate output sequences. Latch 56 has three inputs, CK, RSR and OFF, and a number of outputs equal to the number of LEDs in LED array 12 . Each output corresponds to a separate LED in LED array 12 . Based on the preprogrammed sequence, latch 56 activates each of the appropriate output signals sequentially. It should be noted that latch 56 can also be programmed to sequence the output in different orders other than sequentially, although it is preferred in this invention to have sequential activation of LEDs in color order.
[0039] Driver 58 is essentially a buffer between latch 56 and the LED array 12 . Driver 58 ensures that sufficient power is supplied to the LEDs in LED array 12 and that the current drawn from the outputs of latch 56 is not too great. During normal operation, the output of the driver 58 tracks the output of latch 56 .
[0040] It should be understood that the above circuit descriptions in FIG. 3 and FIG. 4 are only meant to provide an illustration of how LED assembly 30 may be implemented and configured and that many other implementations are possible. LED assembly 30 is not circuit dependent and therefore neither is flame simulating device 10 . There are many possible circuit configurations that may be used in alternative embodiments to achieve a result substantially similar to that described above.
[0041] Reference is now made to FIG. 5, illustrated therein is the MAIN OPERATION routine 100 utilized by microcontroller 52 to control the output of LED array 12 . The routine commences at step ( 102 ) when the flame simulation device 10 is turned “on”, that is, S switch 20 is manually closed. It is also possible for switch to be closed using various types of activation devices (e.g. a an audio deactivation device as will be described in relation to FIG. 6). At step ( 104 ) microcontroller 20 enables the clock signal and latch 24 by sending an appropriate signal through the SCK 51 and OFF 55 lines respectively.
[0042] At step ( 108 ) microcontroller 52 determines the preprogrammed sequence input and sends the appropriate digital signal to latch 56 through the RSR line 53 . In turn latch 56 generates the appropriate output at step ( 110 ). That is, at step ( 110 ) the LEDs in LED array 12 are turned on in sequential order. Specifically, yellow, orange and red LEDs 12 a , 12 b and 12 c are sequentially activated in a “single LED” and “up/down” sequence according to the color transition rules discussed above.
[0043] As noted, it has been determined that it is beneficial to cycle between yellow and orange, between orange and red, but not between red and yellow, in order to minimize the “color” transition difference. Accordingly, microcontroller 52 is programmed to follow these color transition rules when executing LED lighting sequence steps and activating specific LEDs. Application of these color transition rules is illustrated in the duty cycle graphs of FIG. 2 which indicate the following LED activation sequence: red ( 12 a ), orange ( 12 b ), yellow ( 12 c ), orange ( 12 b ), yellow ( 12 c ), orange ( 12 b ), red ( 12 a ), orange ( 12 b ), yellow ( 12 c ).
[0044] Then at step ( 114 ) microcontroller 52 determines whether or not flame simulation device 10 has been turned “off”. If not, then the routine cycles back to step ( 108 ) and repeats itself. If so, then at step ( 116 ), microcontroller 52 disables the clock and latch 56 by sending the appropriate signals over the SCK 51 and OFF 55 lines respectively. Flame simulating device 10 is then inactive until the switch closes again at step ( 102 ).
[0045] [0045]FIG. 6 illustrates an optional audio deactivation device 150 that can be used to deactivate light source driving circuit 18 . Audio deactivation device 150 allows the user to in effect “blow out” the flame (as a user typically “blows out” a candle) by blowing air close to the LED array 12 as will be described. Specifically, audio deactivation device 150 includes a microphone 152 and another latch 156 . It should be understood that any other sound sensitive device (e.g. a piezo crystal buzzer, etc.) could be utilized instead of microphone 152 . Preferably, microphone 152 is positioned in close proximity to LED array 12 for most intuitive effect.
[0046] When a user blows at LED array 12 , microphone 152 senses the sound increase and a large delta spike in circuit resistance results within circuit resistors (shown as 15 Kohm, 29 Kohm, 4.7 Kohm), capacitor (shown as 104 microfarads) and transistor T 2 . In turn, the trigger input TG of latch 156 is enabled and causes latch 156 to disrupt the voltage being provided at VDD to output Cout which is connected to the power input (not shown) of light source driving circuit 18 .
[0047] In addition, it is contemplated that a photosensor-based turn-off circuit (not shown) could also be utilized to deactivate light source driving circuit 18 and audio deactivation device 150 when a photosensor (not shown) is exposed to light. When the power is removed from light source driving circuit 18 and audio deactivation device 150 , the latches associated with these circuits are reset. Once the light dims, the photosensors will emit an operational signal (i.e. time to turn flame simulating device 10 back on) and the associated latches will then be enabled again to power LED array 12 . The use of such a photosensor-based turn-off circuit results in additional power savings since the unit would be turned off during daylight hours and does not require manual deactivation and activation (i.e. in a restaurant or other hospitality setting).
[0048] Various alternatives to the preferred embodiment of the flame simulating device 10 are possible. For example, the LED array 12 of flame simulating device 10 can be fabricated out of different types of LEDs that may, for example, have different colors, intensities and dispersion angles. Furthermore, it is also possible to implement the LED array 12 with fewer or larger numbers of LEDs. Also, light source driving circuit 18 could be adapted to activate at least one LED at a time although there would be a commensurate rise in the required power from power supply 16 and a reduction in the lifetime of a set (i.e. finite such as a battery) power supply 16 . In addition, the shape, size and material of the shell 40 may be varied. Furthermore, power source 16 can be comprised of any appropriate type of battery. While it is preferred for power source 16 to have an output voltage in the range of 3 to 12 V DC, it is possible to manufacture the decorative display assembly to operate outside this range. In addition, many other circuit configurations may be used to implement the same or similar functionality.
[0049] As will be apparent to persons skilled in the art, various modifications and adaptations of the structure described above are possible without departure from the present invention, the scope of which is defined in the appended claims. | A flame simulating device includes a substantially translucent shell having a hollow interior, a plurality of colored light sources, positioned within the hollow interior of said shell and a light source driving device for selectively activating each of said plurality of light sources. Each of the light sources are alternately and individually activated to have active periods and such that the surface of said shell is illuminated to produce an animated flame effect. In one example implementation, yellow, orange and red LEDs are positioned at varying heights within the flame-shaped shell and activated on and off in a sequence that follows a set of color transition rules in order to provide a close simulation of the flickering of a flame. During their active periods, LEDs are blinked on and off to conserve power. | 5 |
BACKGROUND OF INVENTION
[0001] The present invention relates generally to door handles for automotive vehicles, and in particular to door handles that automatically extend out for use and retract flush to the vehicle when not in use.
[0002] For some automotive vehicles, door handles needed for opening the vehicle doors sometimes detract from the overall aesthetic appearance of the vehicle. This is particularly true for door handles that extend outboard of the outer surface of the door.
[0003] Some have attempted to overcome this by employing a door handle that is partially flush with the outboard surface of the door. That is, the top portion of the handle is actually flush with the outside surface of the door, while the outer door panel adjacent to the bottom portion is recessed inboard (or a handle bezel is recessed inboard) enough to allow ones fingers to slide up behind the door handle. So, in reality, these types of door handles are not really flush with the door all of the way around the periphery of the handle. Consequently, the aesthetic appeal achieved with a door handle that is truly flush all of the way around is not achieved.
[0004] Thus a desire has arisen for a way to provide for a fully flush door handle on a vehicle, while still allowing one to use the handle to open the vehicle door.
SUMMARY OF INVENTION
[0005] An embodiment contemplates a door handle assembly for a vehicle door having an outer door panel with a door outboard surface and a door handle cutout. The door handle assembly may comprise a pivot bracket, mountable in the vehicle door, and having a pivot pin mounting flange; a handle arm pivotally mounted to the pivot bracket pivot pin mounting flange at a first location and having a handle support at a second location spaced from the first location; a handle, mounted on the handle support, and including a handle outboard surface with a periphery alignable with the door handle cutout; and a motor assembly, including a motor, mounted in fixed relation to the pivot bracket, and operatively engaging the handle arm to selectively cause pivoting of the handle arm relative to the pivot bracket.
[0006] An embodiment contemplates a vehicle door comprising an outer door panel having an outboard surface and a door handle cutout, and a door handle assembly. The door handle assembly may include a handle arm mounted inside the vehicle door adjacent to the outer door panel and pivotable relative to the outer door panel, with the handle arm having a handle support; a handle, mounted on the handle support, and including a handle outboard surface with a periphery selectively extendable through the door handle cutout, with the handle outboard surface selectively alignable flush with the outboard surface of the outer door panel; a motor assembly, including a motor mounted in fixed relation relative to the outer door panel, and operatively engaging the handle arm to selectively cause pivoting of the handle arm relative to the outer door panel; and a control module operatively engaging the motor assembly to selectively rotate the motor in a first rotational direction and an opposite second rotational direction, whereby rotation of the motor in the first rotational direction results in the handle outboard surface extending outboard of the outboard surface of the outer door panel and rotation of the motor in the second rotational direction allows the handle outboard surface to be made flush with the outboard surface of the outer door panel.
[0007] An embodiment contemplates a method of operating a door handle assembly mounted in a vehicle door having an outer door panel with a door outboard surface, the method comprising the steps of: detecting a handle extension request for a handle of the door handle assembly; actuating a motor assembly to pivot an outboard surface of the handle outboard of the door outboard surface if the handle extension request is detected; unlatching a door e-latch mounted on the vehicle door; detecting if the door e-latch becomes latched; and actuating the motor assembly to pivot the outboard surface of the handle to a position flush with the door outboard surface if the latching of the door e-latch is detected.
[0008] An advantage of an embodiment is an improved aesthetic appearance for a door and door handle on a vehicle, while still enabling a fully functional vehicle door handle.
[0009] An advantage of an embodiment is that the improved aesthetic appearance is achieved while avoiding clearance concerns between the door handle assembly and a movable window in the door.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a side view looking inboard at a portion of a vehicle door.
[0011] FIG. 2 is a perspective view of a portion of a vehicle door, looking outboard and down.
[0012] FIG. 3 is a perspective view of a door handle in a flush position relative to an outboard surface of a vehicle door.
[0013] FIG. 4 is a side view, looking forward, of a portion of a vehicle door, with a door handle in a flush position relative to an outboard surface of the vehicle door.
[0014] FIG. 5 is a perspective view of a door handle in a depressed position relative to an outboard surface of a vehicle door.
[0015] FIG. 6 is a side view, looking forward, of a portion of a vehicle door, with a door handle in a depressed position relative to an outboard surface of the vehicle door.
[0016] FIG. 7 is a perspective view of a portion of a vehicle door, looking upward and forward, with a door handle in an extended position relative to an outboard surface of the vehicle door.
[0017] FIG. 8 is a perspective view of a portion of a vehicle door, looking inboard and forward.
[0018] FIG. 9 is a partially exploded view, looking outboard at a portion of a door handle assembly.
[0019] FIG. 10 is a perspective view, looking outboard and down, of a portion of a door handle assembly.
[0020] FIG. 11 is a perspective view, looking outboard and aft, of a portion of a door handle assembly.
[0021] FIG. 12 is another perspective view of a portion of a door handle assembly.
[0022] FIG. 13 is another perspective view of a portion of a door handle assembly.
[0023] FIG. 14 is another perspective view of a portion of a door handle assembly.
[0024] FIG. 15 is a perspective view of a handle arm of a door handle assembly.
[0025] FIG. 16 is a perspective view of an eccentric motor pivot of a door handle assembly.
[0026] FIG. 17 is a block diagram of door components in communication with an electronic control module.
[0027] FIG. 18 is a flow chart illustrating the door handle process for opening and closing the door.
[0028] FIG. 19 is a flow chart similar to FIG. 17 , but illustrating a second embodiment.
DETAILED DESCRIPTION
[0029] Referring to FIGS. 1-16 , different portions of a vehicle door, indicated generally at 20 , is shown. The door 20 includes an inner door panel 22 and an outer door panel 24 . Between the inner and outer panels 22 , 24 a window regulator assembly 26 , a door handle assembly 28 , a door e-latch 30 , and a movable window 32 are mounted. The movable window 32 mounts to the window regulator assembly 26 and slides into and out of the door 20 . The door e-latch 30 is an electronically controlled latching assembly that engages and disengages a striker (not shown) to hold the door closed and release the door to allow it to be pulled open.
[0030] The door handle assembly 28 mounts to an inboard surface 34 of the outer door panel 24 via a mounting plate 36 . The door handle assembly includes a pivot bracket 38 mounted to the mounting plate 36 . The pivot bracket 38 includes a motor mount flange 40 , a positive stop mounting flange 42 , and a pair of pivot pin mounting flanges 44 .
[0031] A handle arm 46 pivotally mounts to the pivot pin mounting flanges 44 via a pivot pin 48 . A torsion spring 50 (only shown in FIG. 10 ) mounts on the pivot pin 48 and engages the handle arm 46 and pivot bracket 38 such that the upper portion of the handle arm 46 is biased outboard. The handle arm 46 has a cross member 51 , which includes a positive stop hole 52 adjacent to an extension limit switch pin 53 . The handle arm also includes a limit switch pin support 54 adjacent to the positive stop hole 52 , a cam surface 55 adjacent to the extension limit switch pin 53 , and a handle support 56 on an upper end opposite to the pivot pin 48 .
[0032] A door handle 58 mounts on the handle support 56 . The door handle 58 extends into a door handle cutout 60 in the outer door panel 24 and includes an outboard surface 62 having a periphery 64 . The shape of the periphery 64 preferably matches the shape of the door handle cutout 60 , with a small gap 66 of, for example, two millimeters between the two. The outboard surface 62 , when in a door handle flush position (see FIG. 3 ), is flush with the adjacent outboard surface 68 of the outer door panel 24 . The door handle 58 also includes a handle finger recess 70 accessible from the underside of the handle 58 when the door handle 58 is in a handle extended position (see FIG. 7 ). Within the finger recess 70 is mounted a door latch release switch 72 that is accessible by sliding ones fingers into the finger recess 70 .
[0033] One will note that the handle arm 46 can be relatively long, allowing for significant distance between the pivot pin 48 and the handle support 56 . By allowing the pivot pin 48 , and hence the handle pivot axis, to be much lower in the door than the handle support 56 , the door handle 58 can appear to pop straight out of the outer door panel 24 even though it is actually pivoting about the lower pivot location. Moreover, the low pivot location, being significantly lower in the door 20 than the handle 58 generally allows more room for packaging many of the components of the door handle assembly 28 without interfering with the movable window. An acceptable gap 74 between the handle 58 and handle arm 46 is maintained when the handle 58 is pushed to its door handle depressed position (see FIGS. 5 and 6 ). The gap 741 then, is even larger when the door handle 58 is in its handle flush position (see FIGS. 3 and 4 ).
[0034] The door handle assembly 28 includes a motor assembly 75 . A motor bracket 76 mounts to the motor mount flange 40 of the pivot bracket 38 . A reversible motor 78 is mounted to the motor bracket 76 , with motor mounting bolts 80 , and has a motor shaft 82 extending through the motor bracket 76 . An eccentric motor pivot 84 mounts on the motor shaft 82 . The eccentric motor pivot 84 includes a motor shaft bore 86 , within which the motor shaft 82 is secured, and a parallel but axially spaced roller bore 88 . A roller 90 mounts in the roller bore 88 and has a cylindrical portion 92 that engages the cam surface 55 of the handle arm 46 . The surface contact of the roller 90 against the handle arm 46 maintains the position of the handle arm 46 against the bias of the torsion spring 50 . The eccentric motor pivot 84 also includes a threaded hole 94 within which a stop adjustment bolt 96 is mounted. The stop adjustment bolt 96 is axially adjustable in the hole 94 and is oriented to align with a handle flush button 100 , which is mounted on a flange 98 extending from the motor bracket 76 .
[0035] A limit switch bracket 102 mounts to the pivot bracket 38 and supports a handle depression limit switch 104 adjacent to the switch pin support 54 on the handle arm 46 . A pin 106 extends from the switch pin support 54 in contact with a lever arm 108 extending from the handle depression limit switch 104 . A handle extension limit switch 110 mounts to the positive stop mounting flange 42 of the pivot bracket 38 and includes a lever arm 1 12 extending therefrom engaging the extension limit switch pin 53 .
[0036] A positive stop pin 114 is threaded into a hole 116 in the positive stop mounting flange 42 of the pivot bracket 38 and extends through the positive stop hole 52 in the handle arm 46 . A head 118 on the positive stop pin 114 has a diameter that is larger than the positive stop hole 52 . The positive stop pin 114 is threaded into the hole 116 a sufficient distance so that the head 118 will contact the cross member 51 (preventing any more inboard pivoting of the handle arm 46 and door handle 58 ) before the handle arm 46 or door handle 58 can contact the movable window 32 .
[0037] FIG. 17 is a block diagram of some of the door components that are in communication with an electronic control module 120 . The motor 78 is controlled and can be driven in either direction by the control module 120 . The handle flush button 100 , handle depression limit switch 104 , handle extension limit switch 110 , and door latch release switch 72 each communicate with the control module 120 when actuated. Also, the control module 120 controls the opening and closing of the door latch on the door e-latch 30 .
[0038] An optional key fob portion of the system is also shown in FIG. 17 . A key fob receiver 122 is in communication with the control module 120 and receives wireless signals from a key fob 124 . It is configured so that a push of a certain button 126 (for example a door unlock button) on the key fob 124 will transmit a signal to the key fob receiver 122 that requests a door handle extension. This configuration, then, provides an additional way to request a handle extension (other than pushing on the door handle until the handle depression limit switch is actuated).
[0039] The operation of the vehicle door 20 , with reference to FIG. 18 in view of FIGS. 1-17 ), will now be described. Initially, the outboard surface 62 of the door handle 58 , around its entire periphery 64 , is flush with the outboard surface 62 of the outer door panel 24 , and the door 20 is closed. The control module 120 monitors the handle depression limit switch 104 and key fob receiver 122 (if the particular vehicle is so equipped) to determine it a handle extension is requested, block 200 . If not, then monitoring continues, but if it is requested (as indicated by the handle depression limit switch 104 or key fob button 126 being actuated), the door handle 58 is deployed, preferably after a short delay, block 202 .
[0040] The handle 58 is deployed by the controller 120 actuating the motor 78 , which pivots the eccentric motor pivot 84 . The pivoting of the eccentric motor pivot 84 causes the roller 90 , which is offset from the axis of rotation of the motor shaft 82 , to run along the cam surface 55 . This allows the torsion spring 50 to pivot the handle arm 46 , and hence move the door handle 58 outboard. As the door handle 58 approaches its handle extended position, the extension limit switch pin 53 moves outboard with the pivoting handle arm 46 and actuates the handle extension limit switch 110 , at which point the controller 120 stops the motor 78 . The door handle 58 is now fully deployed.
[0041] The controller 120 now determines if the door latch release switch 72 is actuated, block 204 . This switch 72 can be actuated by one sliding fingers into the handle finger recess 70 and engaging the switch 72 . If not actuated, then monitoring of the switch 72 continues, but if it is actuated, then the controller 120 causes the door e-latch 30 to unlatch, block 206 . The specifics of how the door e-latch 30 unlatches the door will not be discussed in detail herein since electronic door latching and unlatching assemblies for use with automotive vehicles are known to those skilled in the art. With the door 20 unlatched, a user can now open the door 20 .
[0042] Upon a user closing the vehicle door 20 , the door e-latch 30 closes. If the e-latch 30 is in a closed position, block 208 , then handle retraction is initiated, block 210 . Handle retraction is accomplished by the controller 120 rotating the motor 78 in the opposite direction, causing the eccentric motor pivot 84 to push the roller 90 along the cam surface 55 . This causes the roller 90 to pivot the handle arm 46 , and hence the door handle 58 , inboard against the bias of the torsion spring 50 . If the release switch 72 is actuated while the door handle 58 is retracting, then the control module 120 will reverse the motor 78 to redeploy to the handle extended position, block 212 . If not, then the handle 58 will continue retracting until it is in the handle flush position. The handle flush position is detected when the stop adjustment bolt 96 contacts the handle flush button 100 , at which point the controller 120 stops the motor 78 . The outboard surface 62 of the door handle 58 is now again flush with the outboard surface 68 of the outer door panel 24 around its entire periphery 64 .
[0043] FIG. 19 illustrates a method according to a second embodiment, which is applicable to the assemblies illustrated in FIGS. 1-17 . Initially, the outboard surface 62 of the door handle 58 , around its entire periphery 64 , is flush with the outboard surface 62 of the outer door panel 24 , and the door 20 is closed. The control module 120 monitors the handle depression limit switch 104 (and key fob receiver 122 , if so equipped) to determine if a handle extension is requested, block 300 . If not, then monitoring continues, if it is requested, the door handle 58 is deployed, preferably after a short delay, block 302 . The controller 120 automatically causes the door e-latch 30 to unlatch, block 306 . With the door 20 unlatched, a user can now open the door 20 .
[0044] Upon a user closing the vehicle door 20 , the door e-latch 30 closes. If the e-latch 30 is in a closed position, block 308 , then handle retraction is initiated, block 310 . If the release switch 72 is actuated while the door handle 58 is retracting, then the control module 120 will reverse the motor 78 to redeploy to the handle extended position, block 312 . If not, then the handle 58 will continue retracting until it is in the handle flush position.
[0045] As an alternative for the embodiment of FIG. 19 , the door latch release switch 72 may be eliminated. In this case, step 312 accomplishes object detection by monitoring the time taken for handle retraction to the handle flush position. If the time the handle 58 is traveling inboard exceeds a predetermined amount of time and the handle 58 still has not reached the handle flush position, an obstruction is assumed and the controller 120 will automatically re-deploy the handle 58 .
[0046] While certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims. | A handle assembly for a vehicle door and a method of operating the handle assembly is disclosed. The door handle assembly may include a pivot bracket mounted in the vehicle door, a handle arm pivotally mounted to the pivot bracket, a handle alignable flush with a door handle cutout, and a motor assembly operatively engaging the handle arm to selectively cause pivoting of the handle arm relative to the pivot bracket. The door handle assembly may also include a handle depression limit switch, a handle flush button, or a handle extension limit switch in communication with a control module that controls the motor. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. Serial No. 13/789,995, filed Mar. 8, 2013, now U.S. Pat. No. 8,863,460, issued Oct. 21, 2014, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to thermally-coated wall anchors and associated veneer ties and anchoring systems for cavity walls. More particularly, the invention relates to anchoring systems with thermally-isolating coated wall anchors and associated components made largely of thermally conductive metals. The system has application to seismic-resistant structures and to cavity walls requiring thermal isolation.
2. Description of the Prior Art
The move toward more energy-efficient insulated cavity wall structures has led to the need to create a thermally isolated building envelope which separates the interior environment and the exterior environment of a cavity wall structure. The building envelope is designed to control temperature, thermal transfer between the wythes and moisture development, while maintaining structural integrity. Thermal insulation is used within the building envelope to maintain temperature and therefore restrict the formation of condensation within the cavity. The integrity of the thermal insulation is compromised when used in conjunction with the prior art metal anchoring systems, which are constructed from thermally conductive metals that facilitate thermal transfer between and through the wythes. The use of the specially designed and thermally-protected wall anchors of the present invention lowers the underlying metal thermal conductivities and thereby reducing thermal transfer.
When a cavity wall is constructed and a thermal envelope created, hundreds, if not thousands, of wall anchors and associated ties are inserted throughout the cavity wall. Each anchor and tie combination form a thermal bridge perforating the insulation and moisture barriers within the cavity wall structure. While seals at the insertion locations deter water and vapor entry, thermal transfer and loss still result. Further, when each individual anchoring system is interconnected veneer-tie-to-wall-anchor, a thermal thread results stretching across the cavity and extending between the inner wythe to the outer wythe. Failure to isolate the steel components and break the thermal transfer, results in heating and cooling losses and potentially damaging condensation buildup within the cavity wall structure. Such buildups provide a medium for corrosion and mold growth. The use of thermally-isolating coated wall anchors removes the thermal bridges and breaks the thermal thread causing a thermally isolated anchoring system with a resulting lower heat loss within the building envelope.
The present invention provides a thermally-isolating coated wall anchor specially-suited for use within a cavity wall. Anchoring systems within cavity walls are subject to varied outside forces such as earthquakes and wind shear that cause abrupt movement within the cavity wall, requiring high-strength anchoring materials. Additionally, any materials placed within the cavity wall require the characteristics of low flammability and, upon combustion, the release of combustion products with low toxicity. The present invention provides a coating suited to such requirements, which, besides meeting the flammability/toxicity standards, includes characteristics such as shock resistance, non-frangibility, low thermal conductivity and transmissivity, and a non-porous resilient finish. This unique combination of characteristics provides a wall anchor well-suited for installation within a cavity wall anchoring system.
In the past, anchoring systems have taken a variety of configurations. Where the applications included masonry backup walls, wall anchors were commonly incorporated into ladder- or truss-type reinforcements and provided wire-to-wire connections with box-ties or pintle-receiving designs on the veneer side.
In the late 1980's, surface-mounted wall anchors were developed by Hohmann & Barnard, Inc., now a MiTek-Berkshire Hathaway Company, and patented under U.S. Pat. No. 4,598,518. The invention was commercialized under trademarks DW-10®, DW-10-X®, and DW-10-HS®. These widely accepted building specialty products were designed primarily for dry-wall construction, but were also used with masonry backup walls. For seismic applications, it was common practice to use these wall anchors as part of the DW-10® Seismiclip® interlock system which added a Byna-Tie® wire formative, a Seismiclip® snap-in device—described in U.S. Pat. No. 4,875,319 ('319), and a continuous wire reinforcement.
In an insulated dry wall application, the surface-mounted wall anchor of the above-described system has pronged legs that pierce the insulation and the wallboard and rest against the metal stud to provide mechanical stability in a four-point landing arrangement. The vertical slot of the wall anchor enables the mason to have the wire tie adjustably positioned along a pathway of up to 3.625-inch (max.). The interlock system served well and received high scores in testing and engineering evaluations which examined effects of various forces, particularly lateral forces, upon brick veneer masonry construction. However, under certain conditions, the system did not sufficiently maintain the integrity of the insulation. Also, upon the promulgation of more rigorous specifications by which tension and compression characteristics were raised, a different structure—such as one of those described in detail below—became necessary.
The engineering evaluations further described the advantages of having a continuous wire embedded in the mortar joint of anchored veneer wythes. The seismic aspects of these investigations were reported in the inventor's '319 patent. Besides earthquake protection, the failure of several high-rise buildings to withstand wind and other lateral forces resulted in the incorporation of a continuous wire reinforcement requirement in the Uniform Building Code provisions. The use of a continuous wire in masonry veneer walls has also been found to provide protection against problems arising from thermal expansion and contraction and to improve the uniformity of the distribution of lateral forces in the structure.
Shortly after the introduction of the pronged wall anchor, a seismic veneer anchor, which incorporated an L-shaped backplate, was introduced. This was formed from either 12- or 14-gauge sheetmetal and provided horizontally disposed openings in the arms thereof for pintle legs of the veneer anchor. In general, the pintle-receiving sheetmetal version of the Seismiclip interlock system served well, but in addition to the insulation integrity problem, installations were hampered by mortar buildup interfering with pintle leg insertion.
In the 1980's, an anchor for masonry veneer walls was developed and described in U.S. Pat. No. 4,764,069 by Reinwall et aL, which patent is an improvement of the masonry veneer anchor of Lopez, U.S. Pat. No. 4,473,984. Here the anchors are keyed to elements that are installed using power-rotated drivers to deposit a mounting stud in a cementitious or masonry backup wall. Fittings are then attached to the stud which include an elongated eye and a wire tie therethrough for deposition in a bed joint of the outer wythe. It is instructive to note that pin-point loading—that is forces concentrated at substantially a single point—developed from this design configuration. This resulted, upon experiencing lateral forces over time, in the loosening of the stud.
There have been significant shifts in public sector building specifications, such as the Energy Code Requirement, Boston, Mass. (see Chapter 13 of 780 CMR, Seventh Edition). This Code sets forth insulation R-values well in excess of prior editions and evokes an engineering response opting for thicker insulation and correspondingly larger cavities. Here, the emphasis is upon creating a building envelope that is designed and constructed with a continuous air barrier to control air leakage into or out of conditioned space adjacent the inner wythe, which have resulted in architects and architectural engineers requiring larger and larger cavities in the exterior cavity walls of public buildings. These requirements are imposed without corresponding decreases in wind shear and seismic resistance levels or increases in mortar bed joint height. Thus, wall anchors are needed to occupy the same ⅜ inch high space in the inner wythe and tie down a veneer facing material of an outer wythe at a span of two or more times that which had previously been experienced.
As insulation became thicker, the tearing of insulation during installation of the pronged DW-10X® wall anchor, see infra, became more prevalent. This occurred as the installer would fully insert one side of the wall anchor before seating the other side. The tearing would occur at two times, namely, during the arcuate path of the insertion of the second leg and separately upon installation of the attaching hardware. The gapping caused in the insulation permitted air and moisture to infiltrate through the insulation along the pathway formed by the tear. While the gapping was largely resolved by placing a self-sealing, dual-barrier polymeric membrane at the site of the legs and the mounting hardware, with increasing thickness in insulation, this patchwork became less desirable. The improvements hereinbelow in surface mounted wall anchors look toward greater insulation integrity and less reliance on a patch.
As concerns for thermal transfer and resulting heat loss/gain and the buildup of condensation within the cavity wall grew, focus turned to thermal isolation and breaks. Another prior art development occurred in an attempt to address thermal transfer shortly after that of Reinwall/Lopez when Hatzinikolas and Pacholok of Fero Holding Ltd. introduced their sheetmetal masonry connector for a cavity wall. This device is described in U.S. Pat. Nos. 5,392,581 and 4,869,043. Here a sheetmetal plate connects to the side of a dry wall column and protrudes through the insulation into the cavity. A wire tie is threaded through a slot in the leading edge of the plate capturing an insulative plate thereunder and extending into a bed joint of the veneer. The underlying sheetmetal plate is highly thermally conductive, and the '581 patent describes lowering the thermal conductivity by foraminously structuring the plate. However, as there is no thermal break, a concomitant loss of the insulative integrity results. Further reductions in thermal transfer were accomplished through the Byna-Tie® system ('319) which provides a bail handle with pointed legs and a dual sealing arrangement as described, U.S. Pat. No. 8,037,653. While each prior art invention reduced thermal transfer, neither development provided more complete thermal protection through the use of a specialized thermally-isolating coated wall anchor, which removes thermal bridging and improves thermal insulation through the use of a thermal barrier.
Focus on the thermal characteristics of cavity wall construction is important to ensuring minimized heat transfer through the walls, both for comfort and for energy efficiency of heating and air conditioning. When the exterior is cold relative to the interior of a heated structure, heat from the interior should be prevented from passing through the outside. Similarly, when the exterior is hot relative to the interior of an air conditioned structure, heat from the exterior should be prevented from passing through to the interior. The main cause of thermal transfer is the use of anchoring systems made largely of metal, either steel, wire formatives, or metal plate components, that are thermally conductive. While providing the required high-strength within the cavity wall system, the use of steel components results in heat transfer.
Another application for anchoring systems is in the evolving technology of self-cooling buildings. Here, the cavity wall serves additionally as a plenum for delivering air from one area to another. The ability to size cavities to match air moving requirements for naturally ventilated buildings enable the architectural engineer to now consider cavity walls when designing structures in this environmentally favorable form.
Building thermal stability within a cavity wall system requires the ability to hold the internal temperature of the cavity wall within a certain interval. This ability helps to prevent the development of cold spots, which act as gathering points for condensation. Through the use of a thermally-isolating coating, the underlying steel wall anchor obtains a lower transmission (U-value) and thermal conductive value (K-value) and provides non-corrosive benefits. The present invention maintains the strength of the steel and further provides the benefits of a thermal break in the cavity.
In the past, the use of wire formatives have been limited by the mortar layer thicknesses which, in turn are dictated either by the new building specifications or by pre-existing conditions, e.g., matching during renovations or additions the existing mortar layer thickness. While arguments have been made for increasing the number of the fine-wire anchors per unit area of the facing layer, architects and architectural engineers have favored wire formative anchors of sturdier wire. On the other hand, contractors find that heavy wire anchors, with diameters approaching the mortar layer height specification, frequently result in misalignment. This led to the low-profile wall anchors of the inventors hereof as described in U.S. Pat. No. 6,279,283. However, the above-described technology did not address the adaption thereof to surface mounted devices. The combination of each individual wall anchor and tie combination linked together in a cavity wall setting creates a thermal thread throughout the structure thereby raising thermal conductivity and reducing the effectiveness of the insulation. The present invention provides a thermal break which interrupts and restricts thermal transfer.
In the course of preparing this Application, several patents, became known to the inventors hereof and are acknowledged hereby:
Patent
Inventor
Issue Date
2,058,148
Hard
October 1936
2,966,705
Massey
January 1961
3,377,764
Storch
April 1968
4,021,990
Schwalberg
May 1977
4,305,239
Geraghty
December 1981
4,373,314
Allan
February 1983
4,438,611
Bryant
March 1984
4,473,984
Lopez
October 1984
4,598,518
Hohmann
July 1986
4,869,038
Catani
September 1989
4,875,319
Hohmann
October 1989
5,063,722
Hohmann
November 1991
5,392,581
Hatzinikolas et al.
February 1995
5,408,798
Hohmann
April 1995
5,456,052
Anderson et al.
October 1995
5,816,008
Hohmann
October 1998
6,125,608
Charlson
October 2000
6,209,281
Rice
April 2001
6,279,283
Hohmann et al.
August 2001
8,109,706
Richards
February 2012
Foreign Patent Documents
279209
CH
March 1952
2069024
GB
August 1981
It is noted that with some exceptions these devices are generally descriptive of wire-to-wire anchors and wall ties and have various cooperative functional relationships with straight wire runs embedded in the inner and/or outer wythe.
U.S. Pat. No. 3,377,764—Storch—Issued Apr. 16, 1968 Discloses a bent wire, tie-type anchor for embedment in a facing exterior wythe engaging with a loop attached to a straight wire run in a backup interior wythe.
U.S. Pat. No. 4,021,990—Schwalberg—Issued May 10, 1977 Discloses a dry wall construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Like Storch '764, the wall tie is embedded in the exterior wythe and is not attached to a straight wire run.
U.S. Pat. No. 4,373,314—Allan—Issued Feb. 15, 1983 Discloses a vertical angle iron with one leg adapted for attachment to a stud; and the other having elongated slots to accommodate wall ties. Insulation is applied between projecting vertical legs of adjacent angle irons with slots being spaced away from the stud to avoid the insulation.
U.S. Pat. No. 4,473,984—Lopez—Issued Oct. 2, 1984 Discloses a curtain-wall masonry anchor system wherein a wall tie is attached to the inner wythe by a self-tapping screw to a metal stud and to the outer wythe by embedment in a corresponding bed joint. The stud is applied through a hole cut into the insulation.
U.S. Pat. No. 4,869,038—Catani—Issued Sep. 26, 1989 Discloses a veneer wall anchor system having in the interior wythe a truss-type anchor, similar to Hala et al. '226, supra, but with horizontal sheetmetal extensions. The extensions are interlocked with bent wire pintle-type wall ties that are embedded within the exterior wythe.
U.S. Pat. No. 4,875,319—Hohmann—Issued Oct. 24, 1989 Discloses a seismic construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. The wall tie is distinguished over that of Schwalberg '990 and is clipped onto a straight wire run.
U.S. Pat. No. 5,392,581—Hatzinikolas et al.—Issued Feb. 28, 1995 Discloses a cavity-wall anchor having a conventional tie wire for mounting in the brick veneer and an L-shaped sheetmetal bracket for mounting vertically between side-by-side blocks and horizontally on atop a course of blocks. The bracket has a slit which is vertically disposed and protrudes into the cavity. The slit provides for a vertically adjustable anchor.
U.S. Pat. No. 5,408,798—Hohmann—Issued Apr. 25, 1995 Discloses a seismic construction system for a cavity wall having a masonry anchor, a wall tie, and a facing anchor. Sealed eye wires extend into the cavity and wire wall ties are threaded therethrough with the open ends thereof embedded with a Hohmann '319 (see supra) clip in the mortar layer of the brick veneer.
U.S. Pat. No. 5,456,052—Anderson et al.—Issued Oct. 10, 1995 Discloses a two-part masonry brick tie, the first part being designed to be installed in the inner wythe and then, later when the brick veneer is erected to be interconnected by the second part. Both parts are constructed from sheetmetal and are arranged on substantially the same horizontal plane.
U.S. Pat. No. 5,816,008—Hohmann—Issued Oct. 6, 1998 Discloses a brick veneer anchor primarily for use with a cavity wall with a drywall inner wythe. The device combines an L-shaped plate for mounting on the metal stud of the drywall and extending into the cavity with a T-head bent stay. After interengagement with the L-shaped plate the free end of the bent stay is embedded in the corresponding bed joint of the veneer.
U.S. Pat. No. 6,125,608—Charlson—Issued Oct. 3, 2000 Discloses a composite insulated framing system within a structural building system. The Charlson system includes an insulator adhered to the structural support through the use of adhesives, frictional forces or mechanical fasteners to disrupt thermal activity.
U.S. Pat. No. 6,209,281—Rice—Issued Apr. 3, 2001 Discloses a masonry anchor having a conventional tie wire for mounting in the brick veneer and sheetmetal bracket for mounting on the metal-stud-supported drywall. The bracket has a slit which is vertically disposed when the bracket is mounted on the metal stud and, in application, protrudes through the drywall into the cavity. The slit provides for a vertically adjustable anchor.
U.S. Pat. No. 6,279,283—Hohmann et al.—Issued Aug. 28, 2001 Discloses a low-profile wall tie primarily for use in renovation construction where in order to match existing mortar height in the facing wythe a compressed wall tie is embedded in the bed joint of the brick veneer.
U.S. Pat. No. 8,109,706—Richards—Issued Feb. 7, 2012 Discloses a composite fastener, belly nut and tie system for use in a building envelope. The composite fastener includes a fiber reinforced polymer. The fastener has a low thermal conductive value and non-corrosive properties.
None of the above provide a thermally-isolating coated anchoring system that maintains the thermal isolation of a building envelope. As will become clear in reviewing the disclosure which follows, the cavity wall structures benefit from the recent developments described herein that lead to solving the problems of thermal insulation and heat transfer within the cavity wall. The wall anchor assembly is modifiable for use on various style wall anchors allowing for interconnection with veneer ties in varied cavity wall structures. The prior art does not provide the present novel cavity wall construction system as described herein below.
SUMMARY
In general terms, the invention disclosed hereby is a high-strength thermally-isolating surface-mounted anchoring system for use in a cavity wall structure. The wall anchor is thermally-coated and interconnected with varied veneer ties. The veneer ties are wire formatives configured for insertion within the wall anchor and the bed joints of the outer wythe. The veneer ties are optionally compressed forming a low profile construct and swaged for interconnection with a reinforcement wire to form a seismic construct.
The first embodiment of the thermally-isolated wall anchor is a sheetmetal device with a bail type receptor for interconnection with a veneer tie. The wall anchor provides a sealing effect precluding the penetration of air, moisture, and water vapor into the inner wythe structure. The cavity portion and aperture receptor portion and optionally, the attachment portion, the wall anchor mounting surface, the outer surface and the pair of legs receive a thermally-isolating coating. The thermally-isolating coating is selected from a distinct grouping of materials, which are applied using a specific variety of methods, in one or more layers which are cured and cross-linked to provide high-strength adhesion. A matte finish is provided to form a high-strength interconnection. The thermally-coated wall anchors provide an in-cavity thermal break that interrupts the thermal conduction in the anchoring system threads running throughout the cavity wall structure. The thermal coating reduces the U- and K-values of the anchoring system by thermally-isolating the metal components.
The second embodiment of the thermally-isolated anchoring system includes a sheetmetal wall anchor with an L-shaped design having an attachment portion, at least one cavity portion with a receptor portion and a receiving aperture in the receptor portion. A pintle-type veneer tie is interconnected with the wall anchor. The receiving aperture and optionally, the attachment portion and the cavity portion receive a thermally-isolating coating.
It is an object of the present invention to provide new and novel anchoring systems for cavity walls, which systems are thermally isolating.
It is another object of the present invention to provide a new and novel high-strength metal wall anchor which is thermally coated with a thermally-isolating compound that reduces the U- and K-values of the anchoring system.
It is yet another object of the present invention to provide in an anchoring system having an inner wythe and an outer wythe, a high-strength wall anchor that interengages a veneer tie.
It is still yet another object of the present invention to provide an anchoring system which is constructed to maintain insulation integrity within the building envelope by providing a thermal break.
It is a feature of the present invention that the wall anchor hereof provides thermal isolation of the anchoring system.
It is another feature of the present invention that the wall anchor is utilizable with a dry wall construct that secures to a metal stud and is interconnected with a veneer tie.
It is another feature of the present invention that the thermally-coated wall anchor provides an in cavity thermal break.
It is a further feature of the present invention that the wall anchor coating is shock resistant, resilient and noncombustible.
Other objects and features of the invention will become apparent upon review of the drawings and the detailed description which follows.
BRIEF DESCRIPTION OF THE DRAWING
In the following drawing, the same parts in the various views are afforded the same reference designators.
FIG. 1 shows a first embodiment of this invention and is a perspective view of a surface-mounted anchoring system with a thermally isolating wall anchor, as applied to a cavity wall with an inner wythe of dry wall construction with insulation disposed on the cavity-side thereof and an outer wythe of brick interconnected with a veneer tie;
FIG. 2 is a perspective view of the surface-mounted anchoring system of FIG. 1 shown with a thermally-isolating folded wall anchor and a veneer tie threaded therethrough;
FIG. 3 is a perspective view of an alternative design thermally-isolating wall anchor and a veneer tie threaded therethrough;
FIG. 4 is a perspective view of an alternative design thermally-isolating wall anchor with notched tubular legs and a veneer tie threaded therethrough with an interconnected reinforcement wire;
FIG. 5 is a perspective view of a second embodiment of this invention showing a surface-mounted anchoring system with a thermally isolating wall anchor, as applied to a cavity wall with an inner wythe of dry wall construction with insulation disposed on the cavity-side thereof and an outer wythe of brick interconnected with a pintle veneer tie;
FIG. 6 is a perspective view of the anchoring system of FIG. 5 with a low profile pintle veneer tie interconnected therewith; and,
FIG. 7 is a perspective view of an alternative design thermally-isolating wall anchor interconnected with a veneer tie and reinforcement wire, forming a seismic system.
DETAILED DESCRIPTION
Before entering into the Detailed Description, several terms which will be revisited later are defined. These terms are relevant to discussions of innovations introduced by the improvements of this disclosure that overcome the technical shortcoming of the prior art devices.
In the embodiments described hereinbelow, the inner wythe is optionally provided with insulation and/or a waterproofing membrane. In the cavity wall construction shown in the embodiments hereof, this takes the form of exterior insulation disposed on the outer surface of the inner wythe. Recently, building codes have required that after the anchoring system is installed and, prior to the inner wythe being closed up, that an inspection be made for insulation integrity to ensure that the insulation prevents infiltration of air and moisture. Here the term insulation integrity is used in the same sense as the building code in that, after the installation of the anchoring system, there is no change or interference with the insulative properties and concomitantly substantially no change in the air and moisture infiltration characteristics.
In a related sense, prior art sheetmetal anchors and anchoring systems have formed a conductive bridge between the wall cavity and the interior of the building. Here the terms thermal conductivity and thermal conductivity analysis are used to examine this phenomenon and the metal-to-metal contacts across the inner wythe. The present anchoring system serves to sever the conductive bridge and interrupt the thermal pathway created throughout the cavity wall by the metal components, including a reinforcement wire which provides a seismic structure. Failure to isolate the metal components of the anchoring system and break the thermal transfer, results in heating and cooling losses and in potentially damaging condensation buildup within the cavity wall structure.
In addition to that which occurs at the outer or facing wythe, attention is further drawn to the construction at the exterior surface of the inner or backup wythe. Here there are two concerns. namely, maximizing the strength of the securement of the surface-mounted wall anchor to the backup wall and, as previously discussed minimizing the interference of the anchoring system with the insulation and the waterproofing. The first concern is addressed using appropriate fasteners such as, for mounting to metal, dry-wall studs, self-tapping screws. The latter concern is addressed by the flatness of the base of the surface-mounted wall anchor and its thermally-isolating characteristics.
In the detailed description, the veneer reinforcements and the veneer ties are wire formatives. The wire used in the fabrication of veneer joint reinforcement conforms to the requirements of ASTM Standard Specification A951-00, Table 1. For the purpose of this application tensile strength tests and yield tests of veneer joint reinforcements are, where applicable, those denominated in ASTM A-951-00 Standard Specification for Masonry Joint Reinforcement.
The thermal stability within the cavity wall maintains the internal temperature of the cavity wall within a certain interval. Through the use of the presently described thermal-isolating coating, the underlying metal wall anchor, obtains a lower transmission (U-value) and thermal conductive value (K-value) providing a high strength anchor with the benefits of thermal isolation. The term K-value is used to describe the measure of heat conductivity of a particular material, i.e., the measure of the amount of heat, in BTUs per hour, that will be transmitted through one square foot of material that is one inch thick to cause a temperature change of one degree Fahrenheit from one side of the material to the other. The lower the K-value, the better the performance of the material as an insulator. The metal comprising the components of the anchoring systems generally have a K-value range of 16 to 116 W/m K. The thermal coating disposed on the wall anchor of this invention greatly reduces such K-values to a low thermal conductive (K-value) not to exceed 1 W/m K. Similar to the K-value, a low thermal transmission value (U-value) is important to the thermal integrity of the cavity wall. The term U-value is used to describe a measure of heat loss in a building component. It can also be referred to as an overall heat transfer co-efficient and measures how well parts of a building transfer heat. The higher the U-value, the worse the thermal performance of the building envelope. Low thermal transmission or U-value is defined as not to exceed 0.35 W/m 2 K for walls. The U-value is calculated from the reciprocal of the combined thermal resistances of the materials in the cavity wall, taking into account the effect of thermal bridges, air gaps and fixings.
Referring now to FIGS. 1 through 4 , the first embodiment shows an anchoring system with a thermally isolating wall anchor that provides an in-cavity thermal break. This system is suitable for recently promulgated standards and, in addition, has lower thermal transmission and conductivity values than the prior art anchoring systems. The system discussed in detail hereinbelow, has a thermally-isolating wall anchor with a bail opening for interengagement with a veneer tie. The wall anchor is surface mounted onto an externally insulated dry wall structure with an optional waterproofing membrane (not shown) between the wallboard and the insulation. For the first embodiment, a cavity wall having an insulative layer of 2.5 inches (approx.) and a total span of 3.5 inches (approx.) is chosen as exemplary.
The surface-mounted anchoring system for cavity walls is referred to generally by the numeral 10 . A cavity wall structure 12 is shown having an inner wythe or dry wall backup 14 . Sheetrock or wallboard 16 is mounted on metal studs or columns 17 , and an outer wythe or facing wall 18 of brick 20 construction. Between the inner wythe 14 and the outer wythe 18 , a cavity 22 is formed. The wallboard 16 has attached insulation 26 .
Successive bed joints 30 and 32 in the outer wythe 14 are substantially planar and horizontally disposed and in accord with building standards are a predetermined 0.375-inch (approx.) in height. Selective ones of bed joints 30 and 32 , which are formed between courses of bricks 20 , are constructed to receive therewithin the insertion portion 68 of the veneer tie 44 of the anchoring system hereof Being surface mounted onto the inner wythe 14 , the anchoring system 10 is constructed cooperatively therewith and is configured to minimize air and moisture penetration around the wall anchor system/inner wythe juncture.
For purposes of discussion, the cavity surface 24 of the inner wythe 14 contains a horizontal line or x-axis 34 and an intersecting vertical line or y-axis 36 . A horizontal line or z-axis 38 , normal to the xy-plane, passes through the coordinate origin formed by the intersecting x- and y-axes. A folded wall anchor 40 as shown in FIGS. 1 and 2 , is constructed from a sheetmetal plate-like body. Alternative design wall anchors 40 are shown in FIGS. 3 and 4 . The wall anchor 40 has an attachment portion 39 for surface mounting on the inner wythe 14 . The attachment portion 39 is comprised of a mounting face or surface 41 and an outer face or surface 43 . A cavity portion 67 having a receptor or apertured receptor portion 63 is contiguous with the attachment portion 39 . The wall anchor 40 is affixed (as shown in FIGS. 1 , 2 , and 4 ) with a pair of legs 42 extending from the mounting surface 41 which penetrate the inner wythe 14 . The pair of legs 42 have longitudinal axes 45 that are substantially normal to the mounting surface 41 and outer surface 43 . Optionally, as shown in FIG. 3 , the wall anchor 40 is constructed without the pair of legs 42 . The wall anchor 40 is a stamped metal construct which is constructed for surface mounting on inner wythe 14 and for interconnection with veneer tie 44 and affixed to the inner wythe 14 with a pair of fasteners 48 . The receptor 63 is adjacent the outer surface 43 and dimensioned to interlock with the veneer tie 44 .
The veneer tie 44 is a wire formative and shown in FIG. 1 as being emplaced on a course of bricks 20 in preparation for embedment in the mortar of bed joint 30 . In this embodiment, the system includes a wall anchor 40 , a veneer tie 44 , and optionally a reinforcement wire 71 .
At intervals along a horizontal line on the outer surface of insulation 26 , the wall anchors 40 are surface mounted. In this structure, where applicable, the pair of legs 42 sheathe the pair of fasteners or mounting hardware 48 . The wall anchors 40 are positioned on the outer surface of insulation 26 so that the longitudinal axis of a column 17 lies within the yz-plane formed by the longitudinal axes 45 of the pair of legs 42 . Upon insertion in the inner wythe 14 , the mounting surface 41 rests snugly against the opening formed thereby and serves to cover the opening, precluding the passage of air and moisture therethrough. This construct maintains the insulation integrity. In FIGS. 1 , 2 , and 4 , the pair of legs 42 have the lower portion removed thereby forming notches which draw off moisture, condensate or water from the associated leg or hardware which serves to relieve any pressure which would drive toward wallboard 16 . This construct maintains the waterproofing integrity.
Optional strengthening ribs 84 are impressed in the wall anchor 40 . The ribs 84 are substantially parallel to the receptor 63 and, when mounting hardware 48 is fully seated so that the wall anchor 40 rests against the insulation 26 , the ribs 84 are then pressed into the surface of the insulation 26 . This provides additional sealing. While the ribs 84 are shown as protruding toward the insulation, it is within the contemplation of this invention that ribs 84 could be raised in the opposite direction. The alternative structure would be used in applications wherein the outer layer of the inner wythe is noncompressible and does not conform to the rib contour. The ribs 84 strengthen the wall anchor 40 and achieve an anchor with a tension and compression rating of 100 lbf.
A thermally-isolating coating or thermal coating 85 is applied to the receptor 63 to provide a thermal break in the cavity. The thermal coating 85 is optionally applied to the cavity portion 67 , the mounting surface 41 , the outer surface 43 and/or the pair of legs 42 to provide ease of coating and additional thermal protection. The thermal coating 85 is selected from thermoplastics, thermosets, natural fibers, rubbers, resins, asphalts, ethylene propylene diene monomers, and admixtures thereof and applied in layers. The thermal coating 85 optionally contains an isotropic polymer which includes, but is not limited to, acrylics, nylons, epoxies, silicones, polyesters, polyvinyl chlorides, and chlorosulfonated polyethelenes. The initial layer of the thermal coating 85 is cured to provide a precoat and the layers of the thermal coating 85 are cross-linked to provide high-strength adhesion to the veneer tie to resist chipping or wearing of the thermal coating 85 .
The thermal coating 85 reduces the K-value and the U-value of the underlying metal components which include, but are not limited to, mill galvanized, hot galvanized, and stainless steel. Such components have K-values that range from 16 to 116 W/m K. The thermal coating 85 reduces the K-value of the veneer tie 44 to not exceed 1.0 W/m K and the associated U-value to not exceed 0.35 W/m 2 K. The thermal coating 85 is not combustible and gives off no toxic smoke in the event of a fire. Additionally, the thermal coating 85 provides corrosion protection which protects against deterioration of the anchoring system 10 over time.
The thermal coating 85 is applied through any number of methods including fluidized bed production, thermal spraying, hot dip processing, heat-assisted fluid coating, or extrusion, and includes both powder and fluid coating to form a reasonably uniform coating. A coating 85 having a thickness of at least about 5 micrometers is optimally applied. The thermal coating 85 is applied in layers in a manner that provides strong adhesion to the veneer tie 44 . The thermal coating 85 is cured to achieve good cross-linking of the layers. Appropriate examples of the nature of the coating and application process are set forth in U.S. Pat. Nos. 6,284,311 and 6,612,343.
The dimensional relationship between wall anchor 40 and veneer tie 44 limits the axial movement of the construct. The veneer tie 44 is a wire formative. Each veneer tie 44 has an attachment portion 64 that interlocks with the receptor 63 . The receptor 63 is constructed, in accordance with the building code requirements, to be within the predetermined dimensions to limit the z-axis 38 movement and permit y-axis 36 adjustment of the veneer tie 44 . The dimensional relationship of the attachment portion 64 to the receptor 63 limits the x-axis movement of the construct. Contiguous with the attachment portion 64 of the veneer tie 44 are two cavity portions 66 . An insertion portion 68 is contiguous with the cavity portions 66 and opposite the attachment portion 64 .
The insertion portion 68 is optionally ( FIG. 4 ) compressively reduced in height to a combined height substantially less than the predetermined height of the bed joint 30 ensuring a secure hold in the bed joint 30 and an increase in the strength and pullout resistance of the veneer tie 44 . Further to provide for a seismic construct, an optional compression or swaged indentation 69 is provided in the insertion portion 68 to interlock in a snap-fit relationship with a reinforcement wire 71 (as shown in FIG. 4 ).
The description which follows is a second embodiment of the thermally-isolating wall anchor and anchoring system that provides an in-cavity thermal break in cavity walls. For ease of comprehension, wherever possible similar parts use reference designators 100 units higher than those above. Thus, the veneer tie 144 of the second embodiment is analogous to the veneer tie 44 of the first embodiment. Referring now to FIGS. 5 through 7 , the second embodiment of the surface-mounted anchoring system is shown and is referred to generally by the numeral 110 . As in the first embodiment, a wall structure 112 is shown. The second embodiment has an inner wythe or backup wall 114 of a dry wall construction with an optional waterproofing membrane (not shown) disposed thereon. Wallboard 116 is attached to columns or studs 117 and an outer wythe or veneer 118 of facing brick 120 . The inner wythe 114 and the outer wythe 118 have a cavity 122 therebetween. Here, the anchoring system has a surface-mounted wall anchor 140 for interconnection with varied veneer ties 144 .
The anchoring system 110 is surface mounted to the inner wythe 114 . In this embodiment like the previous one, insulation 126 is disposed on the wallboard 116 . Successive bed joints 130 and 132 are substantially planar and horizontally disposed and in accord with building standards set at a predetermined 0.375-inch (approx.) in height. Selective ones of bed joints 130 and 132 , which are formed between courses of bricks 120 , are constructed to receive therewithin the insertion portion 168 of the veneer tie 144 of the anchoring system 110 construct hereof. Being surface mounted onto the inner wythe, the anchoring system 110 is constructed cooperatively therewith.
For purposes of discussion, the insulation surface 124 of the inner wythe 114 contains a horizontal line or x-axis 134 and an intersecting vertical line or y-axis 136 . A horizontal line or z-axis 138 , normal to the xy-plane, passes through the coordinate origin formed by the intersecting x- and y-axes. A wall anchor 140 constructed from a metal plate-like body is shown which has an attachment portion 143 that is substantially planar in form and surface mounted on the inner wythe 114 . A cavity portion 145 is contiguous with the attachment portion 143 and extends from the inner wythe 114 into the cavity 122 . The cavity portion 145 contains a receptor portion 163 with a receiving aperture 165 therewithin disposed horizontally in the cavity 122 for interconnection with a veneer tie 144 . A pair of fasteners 148 secures the wall anchor 140 to the inner wythe 114 . In FIGS. 5 and 6 , the wall anchor 140 contains a single receiving aperture 165 for interconnection with a veneer tie 144 . FIG. 7 provides a variation of the wall anchor 140 having a split cavity portion 145 with two receptor portions 163 for interconnection with a veneer tie.
At intervals along the inner wythe 114 , wall anchors 140 are surface mounted. The wall anchors 140 rest snugly against the inner wythe 114 . Optional strengthening ribs 184 are impressed in wall anchor 140 . The ribs 184 are substantially normal to the apertured receptor portion 163 and when mounting hardware 148 is fully seated, so that the wall anchor 140 rests against the insulation 126 , the ribs 184 strengthen the wall anchor 140 and achieve an anchor with a tension and compression rating of 100 lbf.
The veneer tie 144 is shown in FIG. 5 as being emplaced on a course of bricks 120 in preparation for embedment in the mortar of bed joint 130 . In this embodiment, the system includes a wall anchor 140 and a veneer tie 144 with an optional reinforcement wire 171 to form a seismic construct.
The dimensional relationship between wall anchor 140 and veneer tie 144 limits the axial movement of the construct. The veneer tie 144 is a wire formative. Each veneer tie 144 has an attachment portion 164 that interengages with the apertured receptor portion 163 . As shown in FIGS. 5 through 7 , the attachment portion 164 of the veneer tie 144 is a pintle construct. To further protect against veneer tie 144 pullout, securement portions 181 are formed from the pintle. The apertured receptor portion 163 is constructed, in accordance with the building code requirements, to be within the predetermined dimensions to limit the z-axis 138 movement and permit y-axis 136 adjustment of the veneer tie 144 . The dimensional relationship of the attachment portion 164 to the apertured receptor portion 163 limits the x-axis movement of the construct and prevents disengagement from the anchoring system. Contiguous with the attachment portion 164 of the veneer tie 144 are cavity portions 166 . An insertion portion 168 is contiguous with the cavity portions 166 and opposite the attachment portion 164 .
The insertion portion 168 is (as shown in FIGS. 5 and 6 ) optionally compressively reduced in height to a combined height substantially less than the predetermined height of the bed joint 130 ensuring a secure hold in the bed joint 130 and an increase in the strength and pullout resistance of the veneer tie 144 . Further to provide for a seismic construct, a compression or swaged indentation 169 is provided in the insertion portion 168 (as shown in FIG. 7 ) to interlock in a snap-fit relationship with a reinforcement wire 171 .
A thermally-isolating coating or thermal coating 185 is applied to the receiving aperture 165 to provide a thermal break in the cavity 122 . The thermal coating 185 is optionally applied to the attachment portion 143 , the cavity portion 145 and the receptor portion 163 to provide ease of coating and additional thermal protection. The thermal coating 185 is selected from thermoplastics, thermosets, natural fibers, rubbers, resins, asphalts, ethylene propylene diene monomers, and admixtures thereof and applied in layers. The thermal coating 185 optionally contains an isotropic polymer which includes, but is not limited to, acrylics, nylons, epoxies, silicones, polyesters, polyvinyl chlorides, and chlorosulfonated polyethelenes. The initial layer of the thermal coating 185 is cured to provide a precoat and the layers of the thermal coating 185 are cross-linked to provide high-strength adhesion to the veneer tie to resist chipping or wearing of the thermal coating 185 .
The thermal coating 185 reduces the K-value and the U-value of the underlying metal components which include, but are not limited to, mill galvanized, hot galvanized, and stainless steel. Such components have K-values that range from 16 to 116 W/m K. The thermal coating 185 reduces the K-value of the veneer tie 144 to not exceed 1.0 W/m K and the associated U-value to not exceed 0.35 W/m 2 K. The thermal coating 185 is not combustible and gives off no toxic smoke in the event of a fire. Additionally, the thermal coating 185 provides corrosion protection which protects against deterioration of the anchoring system 110 over time.
The thermal coating 185 is applied through any number of methods including fluidized bed production, thermal spraying, hot dip processing, heat-assisted fluid coating, or extrusion, and includes both powder and fluid coating to form a reasonably uniform coating. A coating 185 having a thickness of at least about 5 micrometers is optimally applied. The thermal coating 185 is applied in layers in a manner that provides strong adhesion to the veneer tie 144 . The thermal coating 185 is cured to achieve good cross-linking of the layers. Appropriate examples of the nature of the coating and application process are set forth in U.S. Pat. Nos. 6,284,311 and 6,612,343.
As shown in the description and drawings, the present invention serves to thermally isolate the components of the anchoring system reducing the thermal transmission and conductivity values of the anchoring system to low levels. The novel coating provides an insulating effect that is high-strength and provides an in cavity thermal break, severing the thermal threads created from the interlocking anchoring system components.
In the above description of the anchoring systems of this invention various configurations are described and applications thereof in corresponding anchoring systems are provided. Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. | Thermally-isolating wall anchors and anchoring systems employing the same are disclosed. A thermally-isolating coating is applied to the wall anchor, which is interconnected with a wire formative veneer tie. The thermally-isolating coating is selected from a distinct grouping of materials, that are applied using a specific variety of methods, in one or more layers and cured and cross-linked to provide high-strength adhesion. The thermally-coated wall anchors provide an in-cavity thermal break that severs the thermal threads running throughout the cavity wall structure, reducing the U- and K-values of the anchoring system by thermally-isolating the metal components. | 4 |
FIELD OF THE INVENTION
This invention relates to a clothing rack that can be used for drying clothes.
BACKGROUND OF THE INVENTION
It is common practice to dry clothes by exposing the recently washed clothes to the atmosphere preferably outdoors. Clothes lines of various types have been proposed from which the garments are suspended, usually by use of clothes pegs. There have also been proposals for portable racks from which the clothes can be suspended. Racks have the advantage that they take up less room than a clothes line and can be used in an indoor environment.
It is considered that there is a need to improve the versatility of a clothing rack by means of increasing its manoeuvrability, rending the rack easy to assemble and disassemble and ensuring good drying efficiency. The rack should be easy to use and durable, capable of resisting damage due to moisture and exposure to sunlight.
It is these issues that have brought about the present invention.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a clothing rack comprising a free standing frame that supports a plurality of rods from which clothing can be suspended, characterised in that each rod has a corrugated exterior to facilitate passage of air between the clothing and the rod.
DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which:
FIG. 1 is the perspective view of a clothing rack in accordance with the present invention supporting an array of clothing,
FIGS. 2A and 2B are perspective views of the clothing rack in a partially collapsed and collapsed configuration,
FIG. 3A is a perspective view of the clothing rack,
FIG. 3B is an enlarged view of a corrugated rod that forms part of the rack,
FIG. 4A is a side elevation of the rack,
FIG. 4B is a plan view of the rack,
FIG. 4C is an enlarged cross-section view of the area inside circle B of FIG. 4A ,
FIG. 5A is an end elevation of the rack,
FIG. 5B has an enlarged cross-sectional view of the area inside the circle C of FIG. 5A ,
FIG. 6A is an end elevation of the rack, and
FIG. 6B is an enlarged view of the area within the circle D of FIG. 6A .
DESCRIPTION OF THE PREFERRED EMBODIMENT
The clothing rack 10 illustrated in the accompanying drawings essentially comprises a series of metal frame members 20 , 30 & 40 that support nine equally spaced parallel rods 50 from which clothing can be suspended as shown in FIG. 1 . The frame members include a lower frame member 20 , a pair of vertical columns 30 and two horizontal upper frame members 40 that support the rods 50 . As shown in FIG. 3B the rods 50 having longitudinal corrugations 51 . The vertical columns 30 can be detached from the upper and lower frame members 40 , 20 to allow the clothing rack 10 to assume a disassembled configuration as shown in FIG. 2B where the upper frame member 40 and lower frame member 20 are placed in abutting parallel contact with the vertical columns 30 extending horizontally. This allows the assembly to be stored in either a vertical or horizontal configuration.
The lower frame member 20 comprises two parallel elongate beams 21 , 22 that have their ends connected to beams 23 , 24 that respectively constitute the feet of the rack. The ends of each foot 23 , 24 have a castor wheel 25 clipped into an aperture on the underside of the beam so that, as shown in the drawings, the whole rack is readily movable about the castor wheels 25 that are free to rotate through 360° about a vertical axis. Each foot 23 , 24 of the lower frame member 20 has an upstanding lug 26 which is adapted to fit into the end of an open rectangular beam that constitutes the vertical column 30 .
The upper frame member 40 has beams 41 , 42 that form the arms and support for the corrugated rods 50 . As shown in FIG. 5B each arm includes a centrally positioned location block 43 that is secured to the underside of the beam 41 or 42 by a pair of spaced rivets 44 , 45 that extend through the beam. The location block 43 is arranged to be a sliding fit into the upper end of the vertical column 30 and a grub screw 46 extends through the column and into the block to secure the assembly together.
As shown in FIG. 4C the connection of the corrugated rod 50 onto the beams or side arms 41 , 42 is by means of an insert 60 that has a corrugated outer periphery 61 so that it is a smooth sliding fit within the internal corrugated surface of the rod 50 . The interface between the corrugations 51 prevents relative axial rotation of the insert 60 in the rods 50 . The projecting cylindrical end 62 of the insert 60 is stepped down to extend through an aperture 63 in the walls of the beam 42 and there is a further stepped down shank 64 that extends through a smaller aperture 66 in the outer wall. The material is then compressed by a riveting technique to provide a riveted head 67 which rests against the outer surface of the beam 42 to prevent removal of the insert 60 from the beams. Thus the location of the corrugated rods 50 on each beam 41 , 42 effectively fixes the rods in a firm and substantially rigid connection to the beams that constitute the upper frame member 40 .
FIG. 3 illustrates the corrugated nature of each rod 50 . The corrugations 51 are elongate and define an air space between the clothing and the rod to improve ventilation and thus the drying function. The air space also ensures against the build up of moisture that might cause corrosion on the exterior surface of the rods 50 . The facility to allow air to be in close vicinity to the contact points to the clothes on the rods improves the drying feature and reduces the likelihood of staining by dampness or corrosion.
The component parts of the clothing rack 10 described above are preferably constructed from aluminium. The frame members 20 , 40 are rectangular cross-sectional aluminium tubing and the corrugated rods 50 would be extruded in aluminium. It is however understood that the components of the clothing rack 10 could be manufactured from other materials such as plastics or steel or even wood. The vertical columns 30 are secured to the upper and lower frames 40 , 20 by use of grub screws that extend through the wall of the column to threadedly engage the location flange or lug on which the column locates. Thus to disassemble the unit it is a simple matter to simply remove the grub screws and pull the upper and lower frames 40 , 20 from the vertical columns 30 . Fold down the columns as shown in FIG. 2 a and place the upper frame 40 on the lower frame 20 to assume the flattened configuration as shown in FIG. 2 b. The absence of welds gives the rack a cleaner image which is considered visually attractive.
The corrugation of the rods 50 also increases the overall strength of the rods and provides the clothing rack 10 with increased rigidity. | A clothes drying rack including a free standing frame that supports a plurality of rods from which articles of clothing can be suspended. Specifically, the clothes drying rack includes a plurality of rods wherein each rod has corrugated exterior to facilitate passage of air between the clothing and the rod. | 3 |
This invention relates to a new process for synthesising ethylenic compounds from aldehydes or ketones and sulphones.
BACKGROUND OF INVENTION
The most widely known process in current use for the production of ethylenic compounds from aldehydes or ketones comprises reacting these carbonyl compounds with a phosphonium halide, for example triphenyl alkyl phosphonium bromide which itself is obtained by reacting triphenylphosphine with an alkyl bromide. Although this reaction takes place satisfactorily, the starting triphenylphosphine is converted into triphenylphosphine oxide which has to be reduced for recycling. Another method of synthesising ethylenic compounds from aldehydes or ketones comprises reacting the aldehydes or ketones with sulphone, for example with phenyl benzyl sulphone, to form an alcohol sulphone (Journal of Chemical Society PERKIN I, page 1166, 1973) which is then converted into an ethylenic sulphone by treatment with a dehydrating agent such as phosphoric acid. The treatment of this sulphone with a reducing agent, such as aluminium amalgam or a metal hydride, results in splitting of the sulphonyl group and liberates the required ethylenic compound (Journal Chemical Communications, page 351, 1973). The advantage of this method, in which hydroxysulphones are formed as intermediate stage, is that it gives high yields, but unfortunately the successive stages of dehydration and desulphonation each necessitate a different agent and, on completion of dehydration, the ethylenic sulphone obtained has to be dehydrated in order to be able to subject it to the reducing splitting treatment.
SUMMARY OF INVENTION
The present invention relates to a simpler process for the preparation of ethylenic compounds corresponding to the formula: ##STR1## in which R 1 and R 3 , which may be the same or different, represent a hydrogen atom or a methyl radical, R 2 represents a hydrogen atom, a saturated or unsaturated, linear or branched aromatic or aliphatic radical, and R 4 represents a saturated or unsaturated, linear or branched ethylenic or polyenic aliphatic radical, the radicals R 3 and R 4 being attachable to one another to form a ring with the ethylenic carbon, wherein an aldehyde or ketone of the formula R 3 -- CO -- R 4 is reacted with a sulphone of the formula R 1 -- CH(R 2 ) SO 2 R, in which R represents an alkyl, aryl or cycloalkyl radical, in the presence of a basic agent, and the product obtained treated with a reducing agent.
The process according to the invention comprising these two stages of preparation can be represented by the following reaction scheme: ##STR2##
In one advantageous variation, the alcohol sulphone its esterified before treatment with the reducing agent. In this way, it is possible to convert the alcohol sulphone into its mesylic or tosylic or even carboxylic esters, such as for example its acetic ester, by the methods normally used for esterifying alcohols.
The starting sulphones are known products such as, for example, methylphenyl sulphone, ethylphenyl sulphone, isopropylphenyl sulphone, dimethylsulphone. They can also be new products prepared by conventional methods, in particular by reacting an alkaline sulphinate with a monohalogenated derivative, for example with an alkyl halide.
The aldehydes and ketones used are known, optionally saturated aliphatic or aromatic products such as acetone, methylethyl ketone, diethyl ketone, methylvinyl ketone, 6-methyl-2-heptenone, cyclohexanone, acetophenone, benzophenone, acetaldehyde, propionic aldehyde, valeric aldehyde, benzaldehyde, cinnamic aldehyde and their homolognes, acrolein, methacrolein, crotonaldehyde, senecioic aldehyde, citral, vitamin A aldehyde, and apocarotenals.
In the first stage of the process, condensation of the sulphone with the carbonyl compound is carried out by keeping these products in contact in a molar ratio of 1:1 in the presence of a basic agent sufficiently active to anionise the sulphone used. This alkaline agent can be selected from the oxides or hydroxides of alkali metals, the hydrides, amides or alcoholates of alkali metals.
It is also possible to use an active metallation agent, such as an organomagnesium, organolithium or organozinc compound. The quantity of alkaline agent can be varied from 1 to 1.2 mol per mol of sulphone. In general, a molar ratio of 1:1 is perfectly suitable.
The reaction can be carried out either at ambient temperature or at lower temperatures down to -80°C, and preferably in a solvent which is inert under the reaction conditions, such as an aliphatic or aromatic hydrocarbon, an alcohol, an ether or a polar solvent.
The first stage of the process yields an alcohol sulphone.
Of the alcohol sulphones that have been prepared, some are already known, whilst others are new products which, independently of the present process, can be used for other organic syntheses, for example in the preparation of α,β-ethylenic sulphones, known more commonly as vinyl sulphones.
To carry out the second stage of the process, the alcohol sulphone may optionally be esterified as indicated above before being treated with a reducing agent.
Reducing agents particularly suitable for converting the alcohol sulphone into an ethylenic compound are amalgams of alkali metals, such as sodium or potassium amalgam. The amalgam is used in such a quantity that the reaction mass contains a molar quantity of alkali metal equal to or greater than that of the alcohol sulphone. The reaction can be carried out at ambient temperature or at lower temperatures down to -50°C. It is carried out in a solvent such as an aliphatic or aromatic hydrocarbon, an alcohol, a linear or cyclic ether.
The ethylenic compound is isolated from the reaction mixture by extraction with a solvent, by distillation or by any other known method.
A sulphinic derivative, for example an alkali phenyl sulphinate, is formed as secondary product during the second stage of the process, and can be reused in the preparation of the starting sulphone.
DESCRIPTION OF PREFERRED EMBODIMENTS
The process according to the invention is illustrated by the following Examples.
EXAMPLE 1
In a flask filled with nitrogen, 1.56 g (10 - 2 mols) of phenylmethyl sulphone were dissolved in 20 cc of tetrahydrofuran previously distilled in a nitrogen atmosphere. The temperature was then reduced to -78°C, followed by the addition over a period of 2 minutes of 0.64 g (10 - 2 mols) of butyl lithium in solution in hexane. White crystals of lithium-containing phenylmethyl sulphone formed after 3 to 5 minutes, the temperature was allowed to rise to 0° - 10°C. The temperature was then reduced to -30°C to -40°C, followed by the rapid addition of 1.06 g (10 - 2 mol) of freshly distilled benzaldehyde in solution in 5 cc of tetrahydrofuran. The lithium-containing phenylmethyl sulphone precipitate disappeared and the solution was stirred for 1 hour at -20° to -30°C. This was followed by the addition of 1.26 g (1.1 10 - 2 mol) of methyl sulphonic acid chloride in 5 cc of tetrahydrofuran and 4 cc of hexamethyl phosphoramide. The reaction mixture was left standing overnight at -20° to -30°C. and was then hydrolysed with an aqueous saturated solution of ammonium chloride, followed by extraction 3 times with ether. The combined ethereal phases were washed with a saturated aqueous solution of sodium chloride. The ether was evaporated in the absence of heat, leaving 3.45 g of crystals deliquescing at ambient temperature which we stored below 0°C.
These crystals were identified by infrared spectrography as being 2-phenylsulphonyl-1-mesyloxy-1-phenyl ethane.
612 mg (1.8 . 10 - 3 mol) of the crystals previously obtained were dissolved in 6 cc of absolute methanol. The solution was stirred with a magnetic stirrer and its temperature reduced to -30°C. 4 g of sodium amalgam were then added overnight. The mixture was then decanted and the upper layer anionised by vapour-phase chromatography at 100°C, showing that 136 mg of styrene had been obtained without even the slightest trace of ethyl benzene.
EXAMPLE 2
Following the procedure of Example 1, the lithium-containing phenylmethyl sulphone was prepared from 1.56 g of phenylmethyl sulphone in hexane. After the temperature had been reduced to -40°C, 0.98 g (10 - 2 mol) of cyclohexanone in 5 cc of tetrahydrofuran were added, followed by the addition at -25°C of 1.26 g of methyl sulphonic acid chloride in 5cc of tetrahydrofuran and 4 cc of hexamethyl phosphoramide. The reaction mixture was treated in the same way as in the preceding Example and 3.4 g of deliquescent crystals were isolated, being identified by infrared spectrography as 1-phenyl sulphonyl methyl-1-mesyloxy cyclohexane.
682 mg (2.08 . 10 - 3 mols) of the crystals previously obtained were dissolved in 6 cc of methanol. The solution was stirred at -30°C, followed by the addition of 4.2 g of 6% sodium amalgam. The mixture was then stirred overnight at -30°C. The decanted upper layer was found by chromatography to contain methylene cyclohexane identical with the product described in Organic Syntheses, Vol. 40, page 67. Yield: 85%.
EXAMPLE 3
8.5 g (5.10 - 2 mols) of phenylethyl sulphone in 100 cc of benzene were added to 5.10 - 2 mols of ethyl magnesium bromide in 50 cc of ethyl ether at ambient temperature. The mixture was heated under reflux for 1 hour, and then cooled to ambient temperature. Following the addition of 4.8 g (5.25 .sup.. 10 - 2 mols) of freshly distilled valeric aldehyde, the mixture was stirred overnight. The reaction mixture was then treated in the same way as in the preceding Examples, giving 13 g of a crude oil which by distillation in vacuo, gives a fraction of 8.5 g of a yellowish oil, b.p. 4 .10.sup. -3 = 187°- 189°C, which was identified by centesimal analysis and infrared spectrography as being 2-phenyl sulphonyl-3-hydroxy heptane which corresponds to the formula:
CH.sub.3 -- CH (SO.sub.2 C.sub.6 H.sub.5) -- CHOH -- (CH.sub.2).sub.3 -- CH.sub.3
nmr analysis indicated the presence of two diastereo isomers in proportions of 50/50.
100 mg (4.10 - 4 mols) of this product were dissolved in 3 cc of absolute methanol, 0.6 g of 6% sodium amalgam added and the mixture stirred overnight. The upper layer was then decanted and analysed by vapour-phase chromatography. It was found to contain a quantity of 2-heptene corresponding to a yield of 63%.
EXAMPLE 4
Following the procedure of Example 1, 0.850 g of phenylethyl sulphone and 0.430 g of valeric aldehyde were condensed with n-butyl lithium. Methyl sulphonic acid chloride was then added and, after standing overnight at -30°C, the reaction mixture was treated in the usual way, giving 1.72 g of a yellow oil which was 2-phenyl sulphonyl-3-mesyloxy heptane. 282 mg of this product in solution in methanol were then reduced by the addition of 1.5 g of 6 % sodium amalgam, followed by stirring overnight at -30°C. The upper decanted layer was analysed by vapour-phase chromatography. 2-Heptene was obtained in a yield of 80 % without any traces either of 1-heptene or of 3-heptene.
EXAMPLE 5
1.70 g of phenylethyl sulphone were condensed with 0.860 g of valeric aldehyde under the conditions of Example 4. 1.02 g of acetic anhydride were added to the reaction mixture which was then kept for 2 hours at -20°C. 3 g of a colourless oil were obtained, being identified by infrared spectrography as being 2-phenyl sulphonyl-3-acetoxy heptane.
When treated with sodium amalgam under the conditions of the preceding Examples, this product was converted into 2-heptene in a yield of 79 %.
EXAMPLE 6
The procedure is as in Example 5, except that, in the first stage, the acetic anhydride was replaced by 2 g of p-toluene sulphonic acid chloride. After standing overnight at -30°C, the reaction mixture was treated in the usual way, giving 3.9 g of a colourless oil identified by infrared spectrography as being 2-phenyl sulphonyl-3-tosyloxy heptane.
4 g of 6 % sodium amalgam were then added to 760 mg of this product in 6 cc of methanol. The upper decanted layer was found to contain 2-heptene in a quantity corresponding to a yield of 64 %.
EXAMPLE 7
Following the procedure of EXAMPLE 1, 1.70 g of phenylethyl sulphone previously treated with n-butyl lithium in tetrahydrofuran were reacted with 1.26 g of 6-methyl-2-heptenone in 5 cc of the same solvent. After the reaction, the product obtained was treated with a saturated aqueous solution of ammonium chloride, extracted with ethyl ether and then dried over magnesium sulphate. Evaporation of the ether left 2.95 g of an oily product identified by centesimal analysis and chromatography in the vapour phase as being 2-phenyl sulphonyl-3, 7-dimethyl-6-octen-3-ol. The NMR-spectrum of this product revealed the presence of the two diastereo isomers in a ratio of 65 : 35. 655 mg of the alcohol sulphone obtained were contacted overnight at ambient temperature with 3.6 g of 6 % sodium amalgam in 6 cc of absolute ethanol. The mercury and the sodium phenyl sulphinate precipitate were separated: the decanted organic layer was analysed by vapour-phase chromatography. The total yield of 3,7-dimethyl-2,6-octadienes is 52 %, 3,7-dimethyl-6-octen-3-ol having been formed in a quantity corresponding to a yield of 16 %.
If, before being treated with sodium amalgam, the prepared alcohol sulphone is converted into its mesylic ester by reaction with methyl sulphonic acid chloride, 3,7-dimethyl-2,6-octadiene is obtained in a yield of 80 % after reduction with amalgam.
EXAMPLE 8
1.84 g (10 - 2 mol) of phenyl isopropyl sulphone in 20 cc of tetrahydrofuran were treated at -78°C with 0.64 g of n-butyl lithium, followed by the addition at -40°C of 0.580 g of acetone in 5cc of tetrahydrofuran. After 1 hour at -30°C, 1.26 g of methyl sulphonic acid chloride were added, followed by the introduction of 4cc of hexemethyl phosphoramide. After standing overnight at -30°C, the reaction mixture was treated in accordance with the preceding Examples, giving 3.2 g of an oily, yellow product identified by centesimal analysis and infrared spectrography as being 2-phenyl sulphonyl-1-mesyloxy-1,1,2,2-tetramethylethane.
Reduction of this product with sodium amalgam under the conditions of the preceding Examples gave tetramethylethylene in a yield of 52 %.
EXAMPLE 9
Reduction of phenylsulphonyl-2-acetoxy-3-dimethyl-3,7-octene-6 of the formula ##SPC1##
by lithium in ethylenediamine.
338 mg (10 - 3 mole) of sulphone acetate and 70 mg (10 - 2 mol) of hammer-wrought lithium are stirred at -30° in 9 cm 3 of propylamine and 1 cm 3 of ethylene diamine.
When the solution becomes blue, 2 cm 3 of tertiobutanol, then 10 cm 3 of water are added (the protonation is very strong), this mixture is poured into 100 cm 3 of iced water, then extracted by 3 times 10 cm 3 of pentane, the gathered organic phases are washed with a 15 % NaOH lye then with a brine to neutrality. The pentanic solution is dried on magnesium sulphate then analysed by column gas chromatography.
The yield calculated by internal gauging (undecane) is 28 % of a mixture of cis and trans dimethyl-3,7-octadiene-2,6 of the formulae ##SPC2## | The invention relates to a process for the preparation of ethylenic compounds and to certain novel ethylenic compounds produced by the process.
The process comprises the reaction of an appropriate carbonyl compound with a sulphone to obtain an alcohol sulphone which is then reduced to obtain the desired ethylenic compound. | 8 |
FIELD OF THE INVENTION
The invention pertains to using liquid print colors during a printing process of a printing machine in which the print color is transferred from one transfer device to another transfer device and/or to a printing medium.
BACKGROUND OF THE INVENTION
Different approaches can be used to transfer liquid print color onto a printing medium, particularly, onto paper. In this regard, the term “print color” is used in its broadest sense, particularly, as color for relief print, intaglio printing, or offset printing, but it is also used to describe the ink used in inkjet printing. In the instant case, however, print color can also mean liquid toner, primarily used in electrophotographic printing. In different printing processes several transfer devices can be used sequentially, specifically, in offset printing and in electrophotographic printing, the print color can be transferred onto a print blanket and from a print blanket.
One possible liquid components of the print color is a liquid solvent, in particular, a polar solvent, preferably water, whereas environmentally friendly solvents must be given preference.
Print color in a liquid form promotes the development of the image to be transferred, as well as the transferability and the correct distribution of the print color, but it can also result in smearing or it can cause adverse effects upon, or changes in, the printing medium. This can happen even more severely if the printing medium is absorbent paper.
SUMMARY OF THE INVENTION
This invention is to improve the handling of the print color, specifically, to optimize such handling and preferably, to avoid adversely affecting transference of the print color while avoiding adverse effects upon the printing medium.
This invention is achieved by reducing at least one liquid component of the print color. This can be done by reducing the component either before or after the transfer, or partly before and partly after the transfer. In particular, the reduction can occur right on the printed form after development of the image to be transferred, and/or before or after transfer onto a print blanket, and/or before or after transfer onto a printing medium. The timing will mainly depend upon the selected printing process, the selected printing medium and the characteristics of the print color. Reduction of the liquid component following transfer to the printing medium, especially when the printing medium is paper, should preferably occur immediately after the transfer and before excess capillary action causes the liquid to be absorbed too deeply into the printing medium. In particular, it is beneficially intended that the reduction of the liquid component be sufficient enough to prevent moisture from undesirably affecting the printing medium, while at the same time, maintain the natural moisture content of the printing medium, so that it does not dry out.
The liquid component is reduced, preferably through its warming or heating, for example with the use of microwaves to accomplish this purpose. Irradiation with microwaves has several benefits. To a certain degree, the process is self-regulating, because the microwaves, in particular, are absorbed by water constituents that are already present. Thus, the greater the constituency, the more effective the heating. In addition, heating with microwaves is both thorough and volume related. For microwave irradiation, at least one resonator is preferred to generate standing microwaves specifically, resonators, of the type TE10N or TE101 may be used.
In addition, provision can be made according to the invention for increasing the capacity of the print color, and/or a liquid component, to absorb microwaves. This can be done by the use of various measures. It should be mentioned, in particular, that the absorption capacity of the print color can be raised by the use of an additive that has an enhanced capacity to absorb microwaves, that the capacity of the print color can be raised by admixing a liquid component that has an enhanced capacity to absorb microwaves, that the admixture or blending can occur azeotropically, i.e., by constant boiling, that an admixture or blend is formed of at least two liquid components having unlike phases, of which at least one liquid component has an enhanced capacity to absorb microwaves, and that one of the liquid components may be emulsified into the other liquid component and/or that the emulsification is supported or promoted by at least one additive.
In addition, or as an alternative to directly heating the print color, the printing medium itself can be heated. Other developments according to the invention provide for at least one physical parameter to be controlled or regulated as a function of a parameter that is correlated with the energy input into the printing medium onto which print color has been transferred. Thus, the invention does not utilize the application of a simple, flat standard, but rather of variable standards based upon the actual, preferably measured, circumstances.
In this regard the aforementioned energy input can correspond essentially to the amount of the microwave output that is absorbed by the entire system, which includes both the printing medium and the print color, so that according to the invention, the output energy can be compared with, and adjusted to, the absorbed energy in accordance with the actual prevailing circumstances. This in turn is consistent with efficiency control and/or adjustment. In this regard consideration can be given to controlling the transmission in the broadest sense of the word and/or the receiving system itself, which includes the color print and the printing medium, or the handling of the receiving system.
In this regard the invention proposes in detail, regulation of the microwave emitter and/or regulation of the printing medium's speed of travel, and/or adjustment of the resonator, and/or adjustment of the frequency of the microwaves. The last two measures would preferably also be used to achieve higher energy absorption directly in the print color in order to more precisely influence its fusion than would be possible to do indirectly and more problematically via the printing medium.
In terms of a measurable parameter to be used to guide the dependent regulation, the invention proposes preferentially that either the temperature of the printing medium be used, or the microwave energy that is reflected from, and thus not absorbed by, the print color/printing medium system be used. Other measurable parameters, without limit, could be the weight, the thickness, or the water content of the printing medium.
Preferably, at least two resonators will be required for the microwaves in order to assure homogeneous heating of the print color. These should be offset from one another by λ/4 in order to offset the maxima of the standing waves in the resonators correspondingly.
A further development of the invention provides in lieu of this approach for the use of only one resonator that oscillates fully or partially. Another further development of the invention provides that whenever more than two resonators are used, the resonators be offset from one another by a length λ divided by twice the number of resonators. This results in a more even distribution of temperature on the substratum than is achievable when the offset is λ/4. In a preferred embodiment of the invention four resonators are used each of which is offset from the next by λ/8.
In principle all of the frequencies in the microwave range from 100 MHz to 100 GHz can be used. Customarily the ISM frequencies approved for industrial, scientific, and medicinal use, preferably 2.45 GHz, are used. However, use of other frequencies within the above-mentioned broad frequency range can advantageously result in the absorption of a greater percentage of radiation energy.
In particular, the mechanism for such reduction of at least one liquid component of the print color can be installed upstream of, downstream of, or both upstream and downstream of a transfer device. The reduction mechanism incorporates advantageously a heating mechanism, in particular, a microwave irradiator, preferably at least one resonator for generating standing microwaves.
A further development of the mechanism according to the invention, is characterized by at least one resonator for microwaves transmitted from the emitter (microwave source), which generates a standing microwave that is approximately perpendicular to the plane of the printing medium.
A resonator that is installed vertically in this manner has the advantage that it distributes the intensity of its electromagnetic field particularly favorably in the plane of the printing medium. That is to say, across an appropriately limited resonator width a very homogeneous intensity of the electromagnetic field is generated in the plane of the printing medium and at right angles to its direction of travel such that the printing medium and the print color on the printing medium are evenly heated across this width, and also along the length of the printing medium, provided the printing medium is being evenly transported along its direction of travel. Thus, with a resonator according to the invention, a band that is as wide as the resonator itself can be heated sequentially and evenly over the length of the printing medium.
A succeeding further development of the invention provides for the use of more than one resonator, whereby the resonators are installed across the width of the printing medium such that the effective widths of the neighboring resonators necessarily and advantageously overlap so that the printing medium and the print color on the printing medium are evenly, completely, and gaplessly heated over the entire surface of the printing medium. And in this process, as already mentioned, care is taken that the resonator delivers the most homogenous electromagnetic field possible, which can be readily assured in a resonator width of up to about 20 cm, whereby a resonator width of about 4 cm to about 8 cm is preferred.
The resonators should preferably be installed in staggered formation, whereby different formations are possible. For example, the resonators could be installed in two rows one behind the other with spaces between them, which would produce a compact, space-saving arrangement. However, the resonators could also be arranged in a step formation or in a V formation. These formations have the advantage that the toner in the overlapping areas of the resonators' working widths does not cool off between passes of the sequentially installed resonators. This, in turn, prevents the possibility of a buildup of a visible boundary layer that could be caused by repeated heating of the print color in the overlapping areas. In addition, the aforementioned formations offer the advantage that sufficient space remains available for the elements that transport the printing medium in the area of the mechanism according to the invention.
In principle all resonators in use can be fed by a single microwave source. In this process the energy can, for example, be distributed to the individual systems by T pieces.
A homogeneous heating of the image that is to be fused can be more reliably assured if each resonator is fed by its own microwave source. Thus, an uneven heating of the image that is to be fused, which is caused by the resonators' dissimilar levels of microwave dispersion, can be compensated by adjusting the microwave energy for each resonator, whereby the microwave energy is adjusted to match the resonator's level of microwave dispersion.
Nevertheless, a reasonable minimization of the number of microwave sources can sometimes be achieved in that the output of a single microwave generator is distributed to two resonators by T pieces, whereby it is preferably to assure that the two resonators have approximately the same level of microwave dispersion. For example, in a row consisting of four resonators, which are installed across the width of a printing medium, the two middle resonators and the two outer resonators could always be operated in conjunction with one another, such that a symmetrical level of microwave dispersion would always exist with reference to a symmetrical axis running between the two inner resonators. In this way, the number of microwave sources or magnetrons can be reduced by half.
In the plane that divides each resonator and through which the printing medium is transported, thus making it the printing medium plane, no, or only a few, cross currents flow on the resonator chamber's inner wall so that no high level of scattered radiation occurs. In order to establish electrical contact between a resonator's divided areas (half shells) a suitable conductive connector can be used. Of course, connectors can, from the standpoint of geometry, be difficult to create, if several resonators are installed next to one another. It can therefore make sense to establish the electrical contact by connectors that are suitably connected to one another. Such interconnecting will not influence the individual resonators. In this process one may need to take care that contact points of branch connections are located at places at which a high current density exists inside of the resonator.
Independently adjusting the individual resonators for maximal absorption could lead in some circumstances to unsatisfactory results. Reduction results could be uneven. Therefore, in order to obtain an even result the absorption of the printing medium could be optimized in the sequentially following resonators while the previous resonators are turned on.
In addition, the radiation scatter that exits from the pass through openings of the resonator may be reduced by constructing so-called chokes and/or by the use of absorbent materials outside the resonator.
The use of at least one resonator which is about 1 to about 20 cm long in the printing medium's direction of travel can be preferred in order to simplify handling the printing medium, but also to make possible a sufficient output (for example, 1 to 10 KW per resonator) without resulting arcing. In this process the width of the resonator should also be matched with the printing medium's speed of travel. What is involved here is a relative speed (for example, up to 100 cm/s), such that the heating mechanism itself could be moved relative to a resting printing medium, or both could move. It is even conceivable that the heating could be accomplished in a completely static environment.
This invention is for use preferably with a digital, multi-color printing machine.
The invention, and its objects and advantages, will become more apparent in the detailed description of the preferred embodiment presented below.
BRIEF DESCRIPTION OF THE DRAWINGS
In the detailed description of embodiments of the invention presented below from which further characteristics according to the invention can result, to which however the invention is not limited, are shown in the accompanying drawings. The drawings are as follows:
FIG. 1 shows a schematic view of an embodiment of a mechanism according to the invention that is for heating a printed image;
FIG. 2 shows the temperature distribution of a sheet of paper, the measurement having been made by a Bartec R2610 line pyrometer immediately after the sheet of paper left the resonators, and whereby the temperature curve across the width of the paper is shown with first one resonator turned on, then the first two resonators, then the first three resonators and then all four resonators and where the pixel size is approximately 3 mm;
FIG. 3 shows a schematic view of another embodiment of a resonator according to the invention that is used to heat a printed image;
FIG. 4 shows an overhead view of a two-row arrangement of eight resonators of a mechanism according to the invention, which is used to heat a printed image;
FIG. 5 shows an overhead view of an arrangement of seven resonators, arranged in a V formation;
FIG. 6 shows an overhead view of an additional staggered arrangement of eight resonators of a mechanism according to the invention that is used to heat a printed image;
FIG. 7 shows a view of a resonator like the one in FIG. 3 along with connectors; and
FIG. 8 shows a schematic side view of an imaging mechanism of an electrophotographic printing machine.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the accompanying drawings:
FIG. 1 shows schematically, and only as an example, a view of a possible embodiment of a mechanism according to the invention that is to heat a printed image, in particular, for the implementation of the process according to the invention. FIG. 1 shows a section of a conveyor belt 1 on which sheets of sheet-shaped printing medium can be placed one after the other and then transported. This conveyor belt 1 passes through a heating mechanism that includes, among other things, two resonators 2 and 3 that are offset one from the other. The resonators have, in a suitable location, a slit 4 , which is approximately 3 mm to 10 mm high and through which the conveyor belt and the printing medium pass.
As indicated in FIG. 1 , standing microwaves 5 are formed in the resonators 2 and 3 , from which field strength maxima are found in the plane of the conveyor belt 1 or in that of the printing medium located thereon and which heat, in particular, the printing medium and the printed image located thereon so that a liquid component of the image's print color is reduced. As can be seen in FIG. 1 the resonators 2 and 3 are installed such that they are offset from one another by one-quarter of the wave length of the microwaves 5 in order to achieve a corresponding offset of the maxima of the microwave 5 and to heat the printing medium and the image relatively evenly. It should be noted that the wave length of this microwave 5 , which will hereinafter be identified by the λ sign and which corresponds to the course of energy input into the printing medium, corresponds to only half the wave length of the original, free microwave that was fed through a wave guide.
For the purpose of forming a microwave field, resonators 2 and 3 are connected via wave guides (represented in the drawing by lines) to a suitable system for generating microwaves 6 . The conveyor belt 1 and the printing medium located thereon move through the resonators 2 and 3 in the direction of the arrow 7 at a speed, for example, of up to one meter per second. The radiation scatter that exits through the pass through openings of the resonators can be reduced by a so-called choke and/or by the use of absorbent materials located outside the resonators.
FIG. 2 makes it clear that the offset arrangement of the standing microwaves or the courses of the field strengths when four resonators are used leads advantageously to particularly even heating of the printing medium. FIG. 2 shows temperature curves for the printing medium across the width of the printing medium (analyzed or measured in terms of pixels) in degrees Celsius (° C.), the first of which when only one resonator is in use, the second of which when two resonators are in use, the third of which when a combination of three resonators are in use, and the fourth of which when four resonators are in use. The last temperature curve in the series is recognizably even across the width of the substratum at approximately 100° C.
FIG. 3 shows a schematic view of a resonator 21 that, in accordance with the invention, is installed perpendicular to the plane of conveyance of a printing medium which is not shown in this drawing, but which is conveyed in the direction shown by the arrow 22 through a dividing slot 23 of the resonator 21 . The resonator 21 is divided into two parts 21 a and 21 b by the dividing slot, which simultaneously defines the plane of conveyance of the printing medium. Microwaves can be fed into the resonator 21 in the direction shown by the arrow 24 from a microwave source that is not shown, whereby a moveable stop valve 25 is indicated in the resonator part 21 a.
Around the resonator in FIG. 3 , a coordinate system with an x, y, and z axis is shown, with the use of which the orientation of resonator 21 is to be shown. The direction of travel 22 of the printing medium coincides with the y axis, the width of the printing medium runs in the direction of the x axis, and the direction of excitation of the standing wave in the resonator 21 runs perpendicularly in the direction of the z axis.
The intensities E x , E y , and E z of the components of the resonator's electromagnetic field are qualitatively plotted along the axes of the coordinate system, which are each a function of the particular coordinate. It thus turns out that the curve showing the intensity of the electromagnetic field E x in the direction of the x axis, therefore in the direction of the width of the printing medium, is almost square, which means that this intensity is essentially constant, i.e., homogeneous, across the width of the resonator 21 . This results in the printing medium on which the print color is located being heated in proportion to the distribution of intensity, that is, the printing medium is homogeneously heated during its travel in the direction of travel 22 across the x width of the resonator 21 . In this regard, of course, the x width of the resonator 21 is limited by the fact that the field distribution changes if the spread is too great. The result of this could be that the heating profile in the x direction would no longer be homogeneous. Consequently, the x width of the resonators 21 should be limited to less than 20 cm, and should preferably be about 4 cm to 8 cm.
Consequently, for the purpose of covering the entire x width of the printing medium, it is necessary to install several resonators that are distributed across the width of the printing medium. In addition, a staggered arrangement of the resonators 21 offers the advantage that the resonators can be arranged such that there is enough room between them for the emplacement of elements needed to convey the printing medium. In this way the printing medium can be kept in physical contact with the means of conveyance. This, in turn, assures a secure conveyance.
FIGS. 4 through 6 each shows a schematic overhead view of a preferred arrangement of resonators 21 that are to heat a printing medium homogeneously across its entire width. A conveyor belt 26 is indicated under the represented work areas of the resonators; the conveyor belt moves in the direction of travel shown by the arrow 22 and it is for the purpose of conveying the printing medium and to carry it through the dividing slot 23 of the resonators 21 .
FIG. 4 shows a particularly compact arrangement. The resonators 21 are located in rows of four and sequentially in columns of two relative to the direction of travel 22 , whereby each of the resonators 21 is arranged to cover a gap. In FIG. 5 the resonators 21 are staggered one behind the other in a V formation, whereby here, too, the resonators 21 as a group cover the entire width of the conveyor belt 26 . In FIG. 6 the resonators are staggered in steps one behind the other, and once again they cover the entire width of the conveyor belt as a group.
In the three drawings, FIGS. 4 through 6 , the longitudinal edges of the resonators 21 , which following one after the other, always cover the next section of the overall width of the conveyor belt 26 , each of which is in alignment with the others. It is, however, better in terms of homogeneous heating of the printing medium when the effective widths of the resonators 21 and the effective areas that are swept by them overlap one another. Such an overlapping area can advantageously be 1 mm to 300 mm wide, but preferably 1 mm to 10 mm. The preferred number of resonators 21 can then be a function of the width of an individual resonator 21 , the size of the overlapping area, and the width of the printing medium or the conveyor belt 26 . For example, using the arrangement shown in FIG. 4 for a sheet of paper (the printing medium) that is maximally 383 mm wide, 8 resonators can be installed in two rows of four resonators 21 each. Each of these resonators can have an effective width of 54 mm at a right angle to the direction of travel. The two rows of resonators 21 can be at a distance of 525 mm from each other in the direction of travel 22 . The resonators 21 in the two rows can be arranged at right angles to he direction of travel so as to cover gaps, i.e., they can be offset from one another by 47 mm. Taking the given effective width into consideration the effective widths of the resonators 21 that run sequentially in the direction 22 will then overlap by 7 mm.
The arrangements shown in FIGS. 5 and 6 have the additional advantage that the print color does not become cold in the overlapping areas of the resonators 21 during the transition from the effective area of one resonator to that of the next resonator 21 as the printing medium is being further conveyed in the direction of travel 22 . Thus the possible formation of a visible boundary layer caused by renewed heating in the overlapping areas of the resonators 21 can be avoided. The arrangements shown in FIGS. 5 and 6 are also optimized to the effect that only a minimal surface is not in contact with the printing medium's means of conveyance.
FIG. 7 once again shows a schematic view of the resonator 21 that is shown in FIG. 3 , but now with an electrically conductive connecting element 27 that is used to connect part 21 a and part 21 b of the resonator 21 . This provides the electrical connection between the resonator parts 21 a and 21 b so that equalizing currents can flow.
FIG. 8 shows a schematic side view of an imaging mechanism of an electrophotographic printing machine that incorporates at least one heating mechanism according to the invention. The imaging mechanism follows the concept found in the disclosure of U.S. Pat. No. 5,561,507. In principle the process according to the invention could naturally be implemented using printing machines that are equipped or retrofitted in accordance with the invention, in particular, with other printing machines that operate electrophotographically, for example, in accordance with U.S. Pat. No. 5,752,142 or PCT Application No. WO 01/92968.
In the mechanism shown in FIG. 8 a printing medium 31 , which can be either in sheet or roll form, is indicated; this printing medium passes an imaging cylinder 32 of a printing machine which, acting as a transfer device, directly transfers a printed image onto the printing medium 31 . For this purpose the imaging cylinder 32 is evenly charged or discharged by a first corona 33 . Subsequently an image is placed on the imaging cylinder 32 by an exposure unit 34 , which selectively either charges or discharges a photo sensitive layer on the imaging cylinder 32 corresponding to the printed image information, depending upon whether the first corona 33 charged or discharged the imaging cylinder 32 . With the aid of an application roller 35 , which can also be referred to as a transfer device, liquid toner 36 from a tank 37 is transferred to the imaging cylinder 32 , whereby this toner 36 selectively adheres to the imaging cylinder 32 commensurate with the imaging previously accomplished with the exposure unit 34 , and the image that is to be transferred is developed in this way. The application and transfer of the toner 36 are controlled with the aid of wipers 38 and 39 . The transfer of the print image from the imaging cylinder 32 to the printing medium is then accomplished with the aid of a second corona 40 that is located under the printing medium.
Heating mechanisms 41 and/or 42 according to the invention can be mounted at different locations where they will be used to reduce the liquid component of the liquid toner 36 on the imaging cylinder 32 after the print image has been developed, on the application roller 35 before the liquid toner 36 is transferred to the imaging cylinder 32 , and/or on the printing medium after the print image has been transferred. In location 41 the printing medium 31 can also be preheated for this purpose even before the print image has been accepted.
As examples only, resonators like those shown in FIG. 1 are indicated at location 42 , while resonators like those shown in FIG. 3 are indicated at location 41 . Such a use is, of course, optional.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. | Using liquid print color in a printing process in which the print color is transferred from one transfer device onto another transfer device and/or onto a printing medium. To improve handling of the print color, in particular, to optimize it, preferably to avoid adversely affecting transference of the print color and at the same time to avoid adverse effects upon the printing medium, at least one liquid component of the print color is reduced. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of International Application No. PCT/EP2010/063376, filed Sep. 13, 2010, which claims priority to German Application No. 10 2009 041 599.8, filed Sep. 15, 2009, and also claims priority to US Provisional Application No. 61/242,620, filed Sep. 15, 2009, the disclosures of which are hereby incorporated herein by reference in their entirety.
TECHNICAL FIELD
[0002] The technical field relates to aircraft technology and in particular a signal transmission device for exchanging signals between systems or devices in an aircraft. Furthermore, the technical field relates to a control device for an aircraft network, a method for controlling an aircraft network, an input/output device for an aircraft network, a method for identifying an input/output device, a connection switching device, a method for identifying an input/output device in a connection switching device and a program element for carrying out the methods.
BACKGROUND
[0003] In an aircraft, for example in an Airbus A380, a network may be installed, which may connect various devices with each other within the aircraft. Such an aircraft network may be denoted as ADCN (Aircraft Data Communication Network). Various devices, which may comprise a processing unit with its own software and its own processor, may be connected to such a network. These devices may be denoted as CPIOM (Core Processing Input Output Module).
[0004] The processing units or CPIOMs may carry out different programs or applications simultaneously. The respective program software for the application may be loaded manually through the network (ADCN) after the installation of the processing unit in the aircraft, i.e., after the processing unit has been integrated into the network. The software which is loaded onto the corresponding CPIOMs may be taken from storage. Alternatively, a processing unit (CPIOM) may be stored with pre-installed software, and the software may be pre-loaded in the workshop or may be loaded into or onto the CPIOM.
[0005] The storage of pre-installed CPIOM modules may make it necessary for a number of different processing units or CPIOMs to stored, which due to the different software may also comprise different item numbers or part numbers. For example, one aircraft may have seven different processing units and thus seven different part numbers. Because of the pre-configuration, the processing units of the CPIOMs may not be interchangeable.
[0006] In view of the foregoing, there may at least a need for providing an efficient operating of an aircraft network. In addition, other needs, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
[0007] According to an embodiment a control device is provided for an aircraft network, a method is provided for controlling an aircraft network, an input/output device is provided for an aircraft network, a method is provided for identifying an input/output device, a connection switching device, a method for identifying an input/output device and a program element are provided in accordance with embodiments.
[0008] According to an embodiment, the control device for an aircraft network may comprise an application determination device and an application provision device. The application determination device may be adapted for detecting an unconfigured input/output device in the aircraft network and for determining at least one application which relates to the unconfigured input/output device or which is connected to the unconfigured input/output device. The application provision device may be adapted for providing a program (software), which corresponds to the at least one application, for uploading the program on the unconfigured input/output device and thereby configuring the substantially unconfigured input/out device.
[0009] In other words, the control device may monitor the input/output device and if the control device establishes that an unconfigured input/output device is connected to the aircraft network, the control device may determine which input/output device it is or which type of input/output device it is. With information on the type of the input/output device, the control device may be in a position to provide the respective input/output device with the corresponding software or the corresponding program. The control device may then automatically upload the program onto an input/output device, such that the input/output device may be used in the aircraft network, substantially without the necessity of any manual intervention.
[0010] According to another embodiment, a method for controlling an aircraft network may be described, which may initially comprise detecting an unconfigured input/output device in the aircraft network and determining at least one application which may relate to the unconfigured input/output device or which may be associated with the unconfigured input/output device. Further, the method may allow for providing a program which corresponds to at least one determined or identified application and for uploading or downloading this program onto the unconfigured input/output device. In this way, the input/output device may be configured and integrated into the operation of the network.
[0011] The application provision device and the application determination device may be arranged in a common housing of the control device. Alternatively, the application provision device and the application determination device may be arranged as separate devices between which devices an exchange of information may take place. In order to detect the association of an application to an input/output device and vice versa, for example an assignment table or a data base may be used. In this table a correlation between one type of an input/output device and an application and vice versa may be stored. However, also a certain input/output device may be interrelated with exactly one or a number of applications. A certain input/output device or an application may be characterised by an individual feature which may allow for an interrelation to be made. Such an individual feature may be a serial number, a key, a name, a reference or a codification. For an application, the individual feature may be an application identifier and for an input/output device the individual feature may be an input/output device identifier.
[0012] Furthermore, according to another embodiment, an input/output device for an aircraft network may be presented, which comprises a first identification device. The first identification device may be adapted for communicating at least one application running on the input/output device or the type thereof to a control device and/or a connection switching device. The communicating may be initiated by a trigger on the input/output device. Alternatively, the application may be communicated, after an external query (polling), which may be directed from the connection switching device or from the control device to the input/output device. The communication is made by the input/output device to the respective device carrying out the query. The detecting of the application may take place in the input/output device.
[0013] According to another embodiment, a method is described for identifying an input/output device. In this method, at least one application or at least one type of an application or at least one reference of an application, which is running on the input/output device, may be communicated to a control device or to a connection switching device. In this way, the control device of the connection switching device may be able to provide the at least one application, which is running or is supposed to run on the input/output device. For determining the application, for example substantially only the individual identifier of the input/output device may be determined and passed to a control device and/or the connection switching device. The individual identifier may be provided by the input/output device. Alternatively, the individual identifier may be provided by a device which may be arranged outside the input/ output device. In another example, the input/output device may determine the application associated with said input/output device and transmit the respective application identifier to the control device.
[0014] According to yet another embodiment, a connection switching device may be indicated, which comprises a second identification device. The second identification device may be adapted for detecting an input/ output device which may be connected to the connection switching device and for determining the type of input/output device and communicating it to the control device. The second identification device may differ from the first identification device.
[0015] According to another embodiment, a method may be described which comprises the detection of an input/output device in a connection switching device. The input/output device may be connected to the connection switching device.
[0016] According to yet another embodiment, a program element may be indicated, which is adapted for carrying out at least one method selected from a group of methods when executed by a processor. The group comprising a method for controlling an aircraft network, the method for identifying an input/output device and the method for identifying an input/output device in the connection switching device.
[0017] According to yet another embodiment, a computer readable storage medium may be described, which comprises a program code, which program code may carry out at least one method when executed by a processor, which method is selected form the group of methods comprising the method for controlling an aircraft network, the method according for identifying an input/output device and the method according for identifying an input/output device in the connection switching device.
[0018] A computer readable storage medium may be a floppy disk, a hard disk, a hard drive, a USB (Universal Serial Bus) storage medium, an RAM (Random Access Memory), an ROM (Read Only Memory) or an EPROM (Erasable Programmable Read Only Memory). A computer readable storage medium may also denote a data communication network, such as for example the Internet, which may allow the downloading of a program code.
[0019] In order to counteract a system failure in an aircraft network, a corresponding redundancy may be available in the aircraft network. A redundancy may be achieved by the availability of several identical components in the aircraft network and by taking over the function of a component that fails by the identical components.
[0020] If the at least one application is separated from the hardware platform or from the hardware component on which it runs, it may be avoided to retain differently configured devices or systems as redundant systems. Thus, it may be avoided to retain a particular hardware configured with an application, for each application which may fail. If necessary, the configuration of the hardware platform may be carried out depending on the failed applications. Thus, a uniform hardware platform with basic equipment may be provided, on which applications which are necessary for the operation of the aircraft may run. Such applications may be control systems or regulation systems for the air conditioning or for the landing flaps. These applications may be associated to a logical level of application.
[0021] By separating the application level from the hardware level, it may no longer be necessary for the same individually configured processing unit or the same CPIOM (Core Processing Input Output Module) with the same software or application to be present several times in the system. In other words, it may no longer be necessary for an individually configured processing unit, that is to say a processing unit on which an application has already been installed or uploaded, to be kept in reserve. The configuration for the replacement components, that is, the uploading of the application, may not take place substantially until a failure occurs, or substantially during installation, after which it may substantially be adapted to the present failure or the present installation of components or of CPIOMs. With the same number of unconfigured components that only are configured in the event of a failure, a larger number of failure combinations may be achieved as compared to the same number of pre-configured components. In the event that all replacement components provided as redundancies are already in use and a further input/output device which may comprise a higher criticality fails, an application which runs on a replacement component and may comprise a lower criticality may be replaced by an application with a higher level of criticality. A separation of the application level and the hardware level may thus make possible the change of application. Thus, the application may be exchanged independently form the hardware platform. A uniform hardware platform may be used for all applications. Before uploading an application, substantially uniform hardware components may be provided as redundant components. Substantially, only with the uploading of the respective application the hardware components may take over the individual function of a failed component or of a failed input/output device. The same may apply for the installation of a component.
[0022] The hardware level can provide an interface, a programming interface or an API (Application Programming Interface), which may be accessed by an application. According to an example, the hardware level may comprise a firmware, a middleware and/or an operating system. The hardware level may also be denoted as a hardware layer and the application level may be denoted as an application layer. In this way, different applications may be loaded onto a hardware component or onto an input/output device, which are set on the same basis or on the same hardware level. The applications may be stored as a program code or a program element, as a result of which they substantially have only a small space requirement however they may be reproduced at least once or several times, even on different input/output devices. For example, a single redundancy may be provided for different input/output devices with just a single hardware component. The same may apply for an n-fold or a multiple redundancy.
[0023] If the system or the device have an individual configuration, the device, the input/output device or the CPIOM would need to be removed after a failure and replaced by a new device of the same type, that is to say with the same software or application. Because of the multiple existence of part numbers needed to indicate the individual configured equipment or CPIOMs, a storage load may increase.
[0024] When the application that is to be configured on an input/output device is detected and the corresponding program is provided through the aircraft network directly from the control device, the loading of the corresponding software via an external data source, such as for example a CD ROM, may be avoided. Uploading of the applications onto the components may take place in a contact-free manner directly with respect to the component. In particular, the manual loading by a technician to load the software or the program may be avoided.
[0025] Thus, according to an embodiment, there may be an unconfigured replacement device connected to the network, particularly to the aircraft network, which device may be configured in such a way that it may assume the functions or the applications of any other device, after this other device may have failed. The function may be uploaded from the control device or from the control center onto the replacement device, which is to say onto the redundant input/output device or onto the unconfigured CPIOM. After the uploading of the respective application or of the at least one application, the replacement device may take over the function of a failed device.
[0026] Thus, the control device may therefore identify the failed configured processing unit or the configured CPIOM and load software that corresponds to this identified configured CPIOM from an internal memory in the control device. As in one example, the CPIOMs may be designed substantially purely digital, the necessity of providing different part numbers for the software and/or the hardware may be avoided. With the use of non-purely digital CPIOMs, for example, 7 different part numbers may be different not only for the software, but also be different for the hardware, as, for example, different sensors etc. may be connected to the CPIOMs or to the hardware, thus making combinations of hardware and software distinguishable by part numbers.
[0027] During the flight, the control device may be able to automatically, i.e., substantially without the intervention of a technician, replace a failed system, for substantially restoring the full functionality of the aircraft. The automatic configuration may be employed not only for error treatment. During the installation, an unconfigured device may also be detected and provided with an application allocated to the device, so that it may be integrated quickly into the network. The uploading of a function of a failed device onto an initially unconfigured device may take place during the flight.
[0028] Depending on their importance or criticality, the applications or programs may run redundantly and in parallel on several configured input/output devices. This may imply for example that a critical application, as for example the landing system or a control system for the landing flaps, may run on three independent, separate input/output devices, for providing a threefold redundancy. With such a threefold redundancy, it may be possible for two devices or applications to fail and the function relating to the application, for example, the landing flap function, yet to be substantially provided. However, the redundancy may be reduced, as it may be present one time instead of being threefold.
[0029] If an application fails or a device onto which a specific application may be installed, the control device may provide the redundantly available, unconfigured system with a copy of the at least one application of the failed device or CPIOM. In this way, despite the failure of a device, the maximum necessary amount of redundancy may be provided for, as for example in the above example, the availability of three redundant applications is provided for. If this maximum predetermined amount of redundancy is present, a failed device or a failed input/output device may not need to be replaced immediately after a flight. Consequently, the standing time between two flights may not additionally be increased and the maintenance expenditure may thus be reduced.
[0030] In other words, in the event of a failure of only one processing unit, the available unconfigured reserve unit or the unconfigured input/output device may take over the function of the failed processing unit and maintain the predetermined redundancy. The control device may be adapted for maintaining the predetermined redundancy by uploading of corresponding applications onto unconfigured components as long as a sufficiently high number of components are available. In one example, not only a single unconfigured input/output device, component, or a single reserve system may be available, but any number of reserve units may be available. For example, the same number of available devices may also be available as a reserve unit. With the use of the control device according to the present invention, the flight operation may be flexible, i.e. the failure of an input/output device substantially may not lead to any limitations in the further flight operation.
[0031] Redundancy can be increased virtually. Redundancy may actually be increased by the parallel presence of a maximum predetermined number of redundant devices or applications. The provision of an unconfigured input/output device may increase the redundancy virtually, as in the event of the failure of a system of the actual redundancy, this too may be replaced. The safety of an aircraft equipped with a control device may be increased. Redundancy may also be increased to a level in excess of that stipulated by the flight authorities.
[0032] Further, the number of available devices may be reduced in order to arrive at the same redundancy as without the use of the control device, which may result in reducing weight and, cost as fewer devices may be used. If a system that is available for ensuring the actual redundancy fails, the redundancy of the entire system would be either lost or reduced, which may lead to a “downgrading” of the aircraft systems. A downgrading would occur, for example, if, after the failure of an application, only a twofold redundancy instead of a threefold redundancy was available.
[0033] According to a further exemplary embodiment, the control device may comprise an error detection device. The error detection device may be adapted for detecting an error in a configured input/output device. A configured input/output device may be understood to be an input/output device that comprises at least one predeterminable application.
[0034] The application determination device may be adapted in such a way that, when an unconfigured input/output device is detected, it determines the applications which are provided for this input/output device. The application determination device may be adapted for determining the at least one predeterminable application on a configured input/output device in the event of an error, in such a way that at least one application is an application affected by the error in the configured input/output device. In other words, the application determination device may identify in the control device the type of the at least one application to be replaced.
[0035] An error detection device enables a detection of the unconfigured system and its commissioning as well as error elimination. The error detection device may identify the available or predetermined applications on the configured input/output device and pass this information to the application determination device, so that the necessary applications may be provided.
[0036] According to another embodiment, the control device further comprises a connection determination device. The connection determination device may be adapted for re-routing a connection leading to the configured input/output device to the originally unconfigured input/output device. For example, a connection may connect an application to a peripheral device and/or to another application. A connection may be a virtual connection.
[0037] A re-routing, i.e., a re-arrangement of connections, may be carried out within the network. In this way, sensors or actuators or general peripheral devices may be connected to the respectively allocated or associated application. As, in the event of an error, a migration of at least one application from a configured system to an unconfigured device may take place, it may also be necessary to re-route the connections leading to the initially configured input/output device to the initially unconfigured and now newly configured input/ output device. In the case of a migration, an application may be carried out on a different hardware component and/or at a different place than prior to the migration. A migration may be linked to the uploading of an application onto a hardware component. With the help of the connection determination device the peripheral devices may again be connected to the respective applications.
[0038] According to yet exemplary embodiment, the re-routing of a connection may be carried out depending on a priority of an application related to the connections. The priority may be determined by at least one of the criteria selected from the group of criteria comprising the criticality of an application, the signal propagation time, the signal delay time or latency and the number of processing stages. When re-routing connections, it may happen that a connection relating to a critical application is routed via heavily loaded or slow nodes. For this reason, taking into account of the load or the latency time of a node, or of the number of intermediary nodes situated between the periphery and the input/output device may allow for providing for a reaction time or quality of service.
[0039] According to yet another embodiment, the connection determination device may be adapted for communicating with a connection switching device for re-routing the connection. For the communication between the connection switching device and the control device, a communication channel may be established between the connection switching device and the control device, through which channel, information, for example relating to the signal propagation time or the loading of a node, may be exchanged.
[0040] According to yet another embodiment, the control device may be adapted for operating at an aircraft-specific infrastructure, such as for example, an aircraft-specific power supply. Furthermore, the device may also be configured for operating an aircraft-specific network, such as for example, an ARINC 429 or an ARINC 629 or an AFDX (Avionic Full Duplex Network). In particular, a digital and/or an analogue connection of peripheral components such as sensors may be distinguished. The control device may be prepared for the connection of aircraft-specific sensors. Therein, the peripheral components may be connected in all possible ways to the control device or to the aircraft network. Therefore all types of data may be supported. The nature of the data transmission, for example, from the sensors may be analogue, digital (ARINC 429, ARINC 629 etc.) or in any other form. The communication of the CPIOMs with the switches, the IOMs, the SSNMS and the other network components may take place via AFDX according to an embodiment. In other words, for example peripheral devices, such as sensors may be connected to the network digitally and/or in analogue form, the internal network communications may take place via AFDX. A power supply for an aircraft may be a 28V direct current supply.
[0041] An Integrated Modular Avionics (IMA) or a next generation IMA may be implemented. IMA may be another name for an aircraft network. The input/output device or CPIOM may comprise a pin programming or a pin coding as an identification device or in an identification device. The pin coding, that is to say an individual arrangement of pins, allows for the type of an input/output device or for input/output device and thus for the related application or an application identifier to be identified. The pin coding or the pin programming, that is to say, programming through a pin code, enables the control device to determine the applications that relate to the unconfigured input/output device. Pin programming may determine an address for an input/output device. A pin coding may constitute an individual labelling for an input/output device.
[0042] According to a further embodiment, the second identification device or the further identification device may comprise a port, through which the connected input/output device may be identified. Through this port, for example, the individual labelling for the input/output device that is connected to the port may be determined
[0043] According to yet another embodiment, the connection switching device may comprise a memory device. The memory device comprises a dynamic memory range for the storage of virtual connections. By separating a dynamic memory range from a fixed memory range, a dynamic routing of virtual connections or of virtual links may be carried out.
[0044] It should be noted that different are described in relation to different subjects. In particular, certain embodiments were described in relation to device-type claims, while other aspects were described in relation to method-type claims. However, from the previous description and from the description that follows, unless it is described differently, a person skilled in the art would understand that in addition to any combination of features relating to one category of subjects also any other combination of features relating to different categories of subjects is disclosed by this text. In particular, combinations of features concerning a device-type claim and features concerning a method-type claim are disclosed.
[0045] This and other embodiments may be described further in relation to the embodiments described below. Below, embodiments are presented with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] The illustrations in the drawings are schematic and are not to scale. In the following description, the same reference numerals are used for the same or corresponding elements.
[0047] FIG. 1 a shows a block diagram of a control device according to an embodiment;
[0048] FIG. 1 b shows a block diagram of an input/output device for an aircraft network according to an embodiment;
[0049] FIG. 1 c shows a block diagram of a connection switching device according to an embodiment;
[0050] FIG. 2 shows an aircraft network system in an error-free condition according to an embodiment;
[0051] FIG. 3 shows the aircraft network system according to FIG. 2 , with three virtual connections according to an embodiment;
[0052] FIG. 4 shows an aircraft network system with a failed input/output device according to an embodiment;
[0053] FIG. 5 shows an aircraft network system after a restoring of the redundancy according to an embodiment;
[0054] FIG. 6 shows a flow diagram for a method for controlling an aircraft network according to an embodiment;
[0055] FIG. 7 shows a flow diagram for a method for identifying an input/output device according to an embodiment; and
[0056] FIG. 8 shows a flow diagram for a method for identifying an input/output device in a connection switching device according to an embodiment.
DETAILED DESCRIPTION
[0057] The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description.
[0058] FIG. 1 a shows a block diagram of a control device 100 , comprising the application determination device 101 and the application provision device 102 . The application determination device 101 and the application provision device 102 are connected by an internal bus 103 and may access the external connection or the interface 104 . Not shown in FIG. 1 a is the aircraft network or AFDX network, with which the control device 100 or the SSNMS 100 (Software Storage and Network Management Server) is connected to the interface 104 . In the event of a new connection of an input/output module (not shown in FIG. 1 a ) or CPIOM, the application determination device allows for a determination of the applications that relate to the respective CPIOM. For this purpose, the application determination device determines the type of the CPIOM and may provide the determined type of application provision device 102 .
[0059] By way of the internal link 105 , the application provision device 102 may access the data base 106 , in which both the allocation of a CPIOM to corresponding applications and the program code of the respective application are stored. That is to say, the data base 106 also provides a program library, which may be read out by the application determination device via the internal link 105 and may be made available via the internal bus 103 and the external interface 104 to the associated CPIOM.
[0060] For identification purposes, the CPIOM may have a distinct address or a distinct identifier, by way of which the control device 100 or the SSNMS 100 may identify the CPIOM and may determine an application associated to it. The application provision device 102 may thus provide a program from the data base 106 , which corresponds to at least one application which was identified as being associated to the CPIOM. The application provision device 102 may actively upload the corresponding programs actively onto the identified CPIOMs by way of program uploading mechanisms, as for example FTP (File Transfer Protocol). Communication between the application determination device 101 and the application provision device 102 is shown by the double arrow 107 .
[0061] The control device 100 may further comprise the error detection device 108 , which is also connected to the internal bus 103 . The control device may also be constructed to be redundant and may for example be present at least in duplicate. Due to the redundant layout of the control device, the failure of one of the at least two control devices may be tolerated.
[0062] With the help of the error detection device does not only an unconfigured input/output device and its associated software may be determined It is also possible to determine a malfunctioning or a defective configured input/output device and identify one or more applications relating to the configured input/output device and upload these as a copy onto a redundant unconfigured input/ output device. In other words, with the error detection device an error may be detected and the application determination device 102 may be controlled in such a way that the application determination device 102 does not just produce a new configuration of an unconfigured input/output device, but also produces a copy of a failed configured input/output device. The applications can be uploaded onto the input/output device in the form of an image.
[0063] Two operating modes may be distinguished inside the control device 100 , which modes may be switchable by a switch (not shown). The first operating mode may provide an intelligent plug-and-play mechanism, in other words it may provide an intelligent configuration service. With this plug-and-play mechanism an intelligent IMA system may be realised. The plug-and-play operating mode or the configuration operation mode may be of interest for maintenance work or also in the case of system failures.
[0064] The plug-and-play mechanism or the automatic CPIOM detection and the automatic software installation may be activated when a new CPIOM is installed in a network and the system is re-started. By way of appropriate trigger mechanisms, an unconfigured CPIOM or an unconfigured input/output device may signalize to the control device 100 , that it is there and that it may be automatically configured by software.
[0065] In a second operating mode, the system may automatically repair and re-configure itself, with the repair and re-configuration being quickly effected. The repair and configuration may be carried out by an operator or by the system itself, in other words it is carried out substantially autarkic.
[0066] As an unconfigured input/output device is employed, which is only configured as the need arises, it may not be necessary for a number of different part numbers to exist for an input/ output device or for a CPIOM. Storage of replacement parts may be reduced by the omitting of several different part numbers for pre-configured CPIOMs and the risk of faulty parts being present in storage may be reduced.
[0067] FIG. 1 b shows an exemplary embodiment of an input/output device 120 or a CPIOM 120 . The CPIOM comprises a first identification device 121 , which is adapted for passing on at least one application (not shown in FIG. 1 b ) running on the input/output device to a control device 100 (not shown in FIG. 1 b ). The identification device 121 may comprise a pin coding. By way of the pin coding, a pin programming may be carried out on the back side or on the back plane of a rack, to which the input/output device 120 is connected by way of the identification device 121 . The identification device 121 may be designed in the form of a plug and act as an interface between the input/output device 120 and a rack, into which the input/ output device is plugged.
[0068] A connection to the aircraft network may be established by the interface 121 , so that the input/output device 120 and the control device 100 may establish contact via the aircraft network. The identification device 121 may be adapted in such a way that, with a restart or a reset of the input/ output device 120 , a trigger, a request notification or a request signal may be sent to a respective control device 100 , so that the system of the SSNMS 100 may detect a newly installed input/output device 120 or a newly installed CPIOM and automatically upload software, in particular an appropriate software, onto the input/output device 120 .
[0069] The identification device 121 may also be connected to a connection switching device 140 , shown in FIG. 1 c , or to an AFDX switch 140 . For the connection, the AFDX switch 140 may provide ports 141 , 142 . The ports 141 , 142 may serve as an interface for the switch 140 . By way of a port 141 , the connection switching device 140 together with a second identification device 143 may determine the type of the input/output device 120 (not shown in FIG. 1 c ). The second identification device 143 may be adapted for determining the type of an input/output device which is connected to the connection switching device 140 . By way of the switching network 144 , the connection switching device may interconnect, for example via virtual connections, a plurality of input/output devices 120 , which are connected to the ports 141 , 142 . Similarly, the switch 140 may establish a connection to a connected SSNMS 100 (equally not shown in FIG. 1 c ). For establishing the connection with the SSNMS either the existing network may be used or a separate data configuration line may be provided between SSNMS 100 and switch 140 . The gates or interfaces 104 , 121 , 141 , 142 may all correspond to the same standard, according to an embodiment. An example for a standard of interfaces may be AFDX.
[0070] The intelligent “plug-and-play” IMA system, which may be built up by the control device 100 , the input/output device 120 and the connection switching device 140 , may allow for an intelligent error treatment while the aircraft is in operation. For example, in the event of the failure of a complete CPIOM 120 or a complete input/output device 120 , the intelligent network 200 , which if formed by at least one switch 140 , may make use of a CPIOM 120 , which, although unconfigured, is already installed in the network.
[0071] The flow of the error recognition and error correction in an aircraft network 200 is shown in FIG. 2 , FIG. 3 , FIG. 4 , and FIG. 5 . FIG. 2 shows the SSNMS 100 , which is connected to the aircraft network 200 or to the AFDX network 200 . The AFDX network 200 comprises the physical AFDX links 201 , which connect the AFDX switches 140 a , 140 b to other components. The AFDX network 200 is a digital network. The AFDX network 200 forms an aircraft control system 200 .
[0072] The AFDX switches 140 a , 140 b are connected to the central SSNMS 100 , the input/output devices 120 a , 120 b , 120 c , 120 d , the micro switch 202 , the cRDCs (Common Remote Data Concentrator) 203 a , 203 b and the IOMs (input/output modules) 204 a , 204 b . The CPIOMs 120 a , 120 b , 120 c , 120 d contain the same basic software, core software or firmware 205 a , 205 b , 205 c , 205 d . The first three CPIOMs 120 a , 120 b , 120 c shown in FIG. 2 are already configured input/output devices 120 a , 120 b , 120 c , each of which contains four applications.
[0073] The applications are numbered in sequence using a numerical code. The numerical code may be regarded an application identifier. For example, CPIOM 1 120 a comprises the applications 1.1, 1.2, 1.3 to 1.n, where n may represent any natural number that corresponds to the number of applications installed on a CPIOM or to the plurality of installed applications. The second CPIOM, CPIOM 2 120 b , correspondingly comprises the four applications 2.1, 2.2, 2.3 and 2.n, the third CPIOM, CPIOM 3 120 c correspondingly comprises the four applications 3.1, 3.2, 3.3 and 3.n.
[0074] The applications of the configured CPIOMs 205 a , 205 b , 205 c may be redundant applications. In this way, for example, the applications 1.1, 2.2 and 3.3 may correspond to each other and in the event of a failure they may replace each other. The use of redundant applications makes possible that, if for example the third CPIOM module 120 c fails, module 1.1, 2.2 is still available several times. An application may for example be the control of a landing flap. The fourth CPIOM, CPIOM 4 120 d , is substantially an unconfigured CPIOM, a replacement CPIOM or a spare CPIOM 120 d . That means that, apart from the basic software 205 d , the reserve CPIOM or the spare CPIOM comprises no application.
[0075] The intelligent sensors 206 or the smart sensors 206 are also connected to the micro switch 202 via digital links, for example AFDX links 201 . By way of analogue lines 207 , ARINC (Aeronautical Radio Incorporated) lines 207 or CAN (Controller Area Network) lines 207 , sensors 208 or sensors 209 or actuators 209 are connected at the cRDCs 203 a , 203 b to the IOMs 204 a , 204 b . The peripheral devices 206 , 208 , 209 may be connected to the AFDX network 200 via the micro switch 202 , the cRDCs 203 a , 203 b and the IOMs 204 a , 204 b.
[0076] FIG. 3 shows three virtual links 301 , 302 and 303 . The first virtual link 301 leads via the physical AFDX link 201 , in parallel to the second and third virtual link, and connects the second CPIOM 120 b via the AFDX switches 140 a , 140 b to a sensor (not shown) or actuator 209 at a second IOM 204 b . The second virtual link is also routed via the two AFDX switches 140 a , 140 b and connects the second CPIOM 120 b with the third CPIOM 120 c and in particular two applications. The third virtual link 303 leads firstly via the first AFDX 140 a and the micro switch 202 to one of the smart sensors 206 . The unconfigured and redundant CPIOM 120 s is not in use and is available in the event of a failure as a so-called 1:N redundancy. Therein, N denotes the number of devices or of applications for which the CPIOM 120 d may act as a replacement.
[0077] FIG. 4 shows the aircraft network system 200 just after the second CPIOM 120 b has failed. The SSNMS identifies the defective second CPIOM 120 b . The smart and intelligent network 200 , and in particular the SSNMS 100 , which administers the network control function, tries to use the redundant replacement CPIOM 120 d , which has already been installed on the aircraft network 200 . The COIOM 120 d is usable because the standard software or the basic software 205 d has already been installed on it. However, the redundant CPIOM 120 d has not been loaded with any application programs. However, the basic software 205 d may provide an interface, which may be used by the application.
[0078] The network 200 , in particular the SSNMS 100 , detects the second CPIOM 120 b , which is affected by the failure, and also detects the software applications 2.1, 2.2, 2.3 and 2.n originally installed on the CPIOM 120 b . As indicated by the arrow 400 , the SSNMS 100 firstly tries to load the identified applications 2.1, 2.2, 2.3 and 2.n of the second CPIOM 120 b onto the still unconfigured CPIOM 120 d . The flexible loading of the applications may increase the reliability of the aircraft system 200 , which comprises the system components 100 , 120 a , 120 b , 120 c , 120 d , 140 a , 140 b , 202 , 203 a , 204 a , 203 b , 204 b and the links 102 .
[0079] Once the applications have been loaded onto the replacement CPIOM 120 d , the SSNMS determines the new connections for the virtual links 301 , 302 and 303 . The SSNMS 100 is connected to the AFDX switches 140 a , 140 b by the control channels 401 , 402 and exchanges routing information, i.e., information on the progress of the new virtual connections 301 ′, 302 ′, 303 ′. A control channel may be designed as a separate line. A control channel may also be understood as being a communication via an AFDX line or a communication in an AFDX network.
[0080] In this way, the new or re-routed virtual connections 301 ′, 302 ′ and 303 ′ shown in FIG. 5 may result, which connections now connect the third CPIOM 120 c to the fourth CPIOM 120 d , the second IOM 204 b to the forth CPIOM 120 d and the smart sensor 206 to the fourth IOM 120 d . The newly configured fourth CPIOM 120 d now comprises the applications 2.1, 2.2, 2.3 and 2.n of the originally second CPIOM. In this way, a re-configuration has taken place, which this has substantially not affected the peripheral devices. An assignment of corresponding sensors or of peripheral devices to the applications 2.1, 2.2, 2.3 and 2.n may still be established.
[0081] In other words, the plug-and-play-IMA architecture may comprise IMA components and the SSNMS 100 . The plug-and-play IMA aircraft network system comprises the cRDC 203 a , 203 b , the CPIOMs 120 a , 120 b , 120 c and at least one replacement CPIOM 120 d . Furthermore, the aircraft network 200 comprises the IOMs 204 a , 204 b , the AFDX switches 140 a , 140 b , the micro switch 202 and the SSNMS 100 . The use of a substantially unconfigured CPIOM 120 d may allow avoiding that different CPIOMs or input/output boards, which are arranged at certain positions and carry out fixed functions of the CPIOM, have to be used. In this way, the number of part numbers for a CPIOM 120 a , 120 b , 120 c , 120 d may be reduced. The plug-and-play CPIOMs 120 a , 120 b , 120 c , 120 d , which may be configured and loaded by an SSNMS 100 , may be realised as digital CPIOMs. Therein, only a single part number (P/N) may exist.
[0082] As the CPIOMs 120 a , 120 b , 120 c , 120 d are substantially completely realised as digital plug-and-play CPIOMs, the IOMs 204 a , 204 b and the RDCs 203 a , 203 b are provided which substantially collect the analogue data from the sensors 208 , 209 and transmit this data digitally to the ADCN (Aircraft Data Communication Network) 200 . The IMA system 200 or the ADCN 200 without plug-and-play functionality and without error correction functionality may function as a conventional IMA system and for being compatible with a conventional IMA system.
[0083] However, if a system error arises on a CPIOM 120 b and is detected by the SSNMS, the SSNMS 100 loads the affected and lost system software 2.1, 2.2, 2.3, 2.n onto the replacement CPIOM 120 d via the ADCN 200 . In parallel with the transfer of the software or the programs by the SSNMS 100 to the unconfigured CPIOM 120 d , the switches 140 a , 140 b are updated or configured with information on the newly to be established virtual links or virtual connections 301 ′, 302 ′, 303 ′. Updating the switches 140 a , 140 b may be carried out in a specific dynamic software area of the switches 140 a , 140 b or in a special dynamic software area of the connection switching devices 140 a , 140 b , which is separate from the static path information or the static routing information.
[0084] The dynamic routes 401 , 402 of the virtual links 301 ′, 302 ′, 303 ′ may be carried out taking into account certain priority requirements. The newly to be established virtual links 301 ′, 302 ′, 303 ′ should be configured in such a way that overload situations are avoided on the individual switches 140 a , 140 b . The traffic load on the switches 140 a , 140 b is established at the design stage. In particular, an upper limit for the maximum acceptable traffic load for each switch 140 a , 140 b is fixed. In the event of a new configuration or a re-configuration because of a system error or a failure of a CPIOM, the network, and in particular the SSNMS 100 , knows value of the free switching capacity of the connection switching device 140 a , 140 b in each of the connection switching devices. This traffic load may be taken into account by the SSNMS 100 when re-routing or re-locating the virtual links so that Mission Critical Application may still be carried out in real-time.
[0085] In addition to the load, also the delay time or the latency time of the virtual links 301 ′, 302 ′, 303 ′ may be in accordance with the requirements of the system concerned. For example, data relating to flight-critical applications, such as the operation of landing flaps, have to use the shortest possible route through the network 200 , in order to enable the data, particularly the speed of exchanging data, within the required response time to be ensured. In other words, the SSNMS may be adapted in such a way that particular criticality requirements of aircraft systems, such as for example, landing flaps, tail unit or chassis may be taken into account.
[0086] Data relating to an application classified as non critical may take a longer path through the network 200 or accept a longer delay time through a greater number of switches 140 a , 140 b than data relating to flight-critical applications. Longer virtual connections or a greater number of switches to be passed or longer delay times may lead to longer response times. The SSNMS 100 may administer a priority list, in which the maximum acceptable response times for the applications 2.1, 2.2, 2.3 2.n are listed. After the re-configuration, the system 200 functions substantially in the same way as before the failure of the CPIOM 120 b . The failure of a single system may substantially imply no limitations of the flight operation.
[0087] The SSNMS may also determine the procedure to be followed for the repair of a defective CPIOM 120 b . It may use the newly configured CPIOM 120 d as a standard CPIOM and then return the repaired CPIOM 120 b or exchanged CPIOM 120 b into the system as a replacement CPIOM. The configuration of a newly installed CPIOM functions substantially in the same way as error correction, wherein the error detection may be omitted. The control device 100 , the input/output device 120 and the connection switching device 140 may be designed as plug-in cards for a rack system for use in an aircraft.
[0088] The criticality may denote how important or how indispensable a certain system may be for the operation of an aircraft. A system, whose failure may lead to serious consequences, may comprise a higher criticality than a system whose failure may lead to less serious consequences. Thus, for example, the failure of an on-board entertainments system is less critical than the failure of a navigation device. The criticality may provide a priority which may be taken into account when uploading replacement applications in the event of a failure of a CPIOM 120 b . Criticality or priority may be provided by a flight safety authority.
[0089] FIG. 6 shows a flow diagram for a method for controlling an aircraft network 100 in according to an embodiment. Instep S 600 the system, for example an SSNMS 100 , is in an idle state. In step S 601 , the control device detects an unconfigured input/output device 120 d in the aircraft network 200 . An unconfigured input/output device 120 d may be detected in the network, because either a new installation has been effected or because a system component has failed.
[0090] The method may then provide for the determination of at least one application that is to be installed on the unconfigured system 120 d . In the event of a new installation, a reference may be established, by addressing, from an input/output device to an associated application. In the event of a re-configuration when a failure occurs, the application may be determined by a failed application and/or its criticality.
[0091] In step S 602 , a program relating to the identified application is provided, which program corresponds to the identified application and which may be uploaded in step S 603 onto the input/output device. In step S 604 , the system is again in an idle mode.
[0092] FIG. 7 shows a method for identifying an input/output device by the input/output device. In step S 700 the input/output device may be in an idle mode. In step S 701 , the input/output device communicates at least one application, which is running or has run on the input/output device, to the control device 100 or to the connection switching device 140 a , 140 b . The communication may be initiated by a query or by an active error or start detection. In step S 702 , the input/output device is again in an idle mode.
[0093] FIG. 8 shows a flow diagram for a method for identifying an input/output device in a connection switching device. The method starts in step S 800 in an idle mode. In step S 801 , the connection switching device 140 detects a connected input/output device. In particular, the connection switching device detects the type of the connected input/output device. For the detection, the connection switching device 140 may carry out a port query, where an association of the port and a respective type of input/ output device 120 are stored in the connection switching device. The connection switching device may communicate the type of the connected input/output device to the control device 100 . In step S 802 , the method is again in an idle mode.
[0094] Additionally, it should be noted that the terms “having” and “comprising” do not exclude other elements or steps and that “a” and “an” does not exclude a plurality. It should also be noted that features or steps, described with reference to one of the above embodiments, may also be used in combination with other features or steps of other embodiments described above. In addition, while at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. | Methods and apparatus are described for an aircraft network that permits an automatic configuring and/or repairing of the network. | 6 |
This application is a continuation-in-part of application Ser. No. 07/051,665, filed May 18, 1987 now abandoned.
BACKGROUND TO THE INVENTION
The present invention relates to certain novel antibiotics, which we have named "mureidomycins A, B, C and D", and also provides a method for preparing them and an antibacterial composition containing at least one of them as the active ingredient.
As resistance to conventional antibiotics becomes increasingly established in common strains of pathogenic bacteria, the need for a wider variety of antibiotics for use in the fight against such bacteria becomes ever more crucial. Although this need can be, and sometimes is, met by chemical modification of existing classes of antibiotic, the discovery of a wholly new class of antibiotic leads to exciting possibilities in the treatment of diseases caused by pathogenic bacteria.
We have now discovered a new class of antibiotics, which we have named the "mureidomycins" and have isolated 4 members of this class, which we have called "mureidomycins A, B, C and D", from the fermentation broth produced by a newly isolated microorganism named strain SANK 60486. This microorganism was isolated from soil and identified to be a strain of the species Streptomyces. We have found that these new antibiotics are particularly effective against gram-negative bacteria, most especially strains of the genus Pseudomonas.
BRIEF SUMMARY OF INVENTION
It is, therefore an object of the present invention to provide, as a new composition of matter, certain new compounds having useful antibacterial activities.
It is a further object of the invention to provide a pharmaceutical composition containing at least one such compound as the active component and a method for the treatment or prophylaxis of bacterial infections employing at least one such compound as the active component.
The new compounds of the present invention are mureidomycins A, B, C and D which are represented by the following structural formula: ##STR1##
For mureidomycin A, R 1 represents a uracil group and R 2 represents a hydrogen atom; mureidomycin B, R 1 represents a dihydrouracil group and R 2 represents a hydrogen atom; mureidomycin C, R 1 represents a uracil group and R 2 represents a glycine group; and mureidomycin D, R 1 represents a dihydrouracil group and R 2 represents a glycine group.
The mureidomycins are further identified and defined by their physico-chemical properties, as follows:
Mureidomycin A has the following physico-chemical properties:
1) Character and appearance: Amphoteric, soluble in water, white powder;
2) Specific rotation: [α] D 25 =+40.9° (c=0.69, 50% v/v aqueous methanol);
3) Elemental analysis: C, 49.73%; H, 5.65%; N, 12.08%; S, 3.40%--measured as the hydrate;
4) Molecular weight: 840 (high resolution mass spectrum), FAB MS: 841.31798 (QM + ) (FAB MS is Fast Atom Bombardment Mass Spectroscopy);
5) Molecular formula: C 38 H 48 N 8 O 12 S 1 ;
6) Products resulting from acid hydrolysis: Uracil, m-tyrosine, 2-amino-3-N-methylaminobutyric acid;
7) Ultraviolet absorption spectrum: λ max nm (E 1 cm 1% ) 260 nm (348) in neutral water; 258 nm (358) in 0.01N aqueous HCl; 240 nm (499), 265 nm (330, shoulder) and 295 nm (78, shoulder) in 0.01N aqueous NaOH; the spectra are shown in FIGS. 1A and 1B of the accompanying drawings;
8) Infrared absorption spectrum (KBr), υ max cm -1 : the spectrum measured in a KBr disk is shown in FIG. 2 of the accompanying drawings;
9) Nuclear magnetic resonance spectrum, δ ppm: the spectrum (400 MHz) was measured in dimethyl sulfoxide using TMS (tetramethylsilane) as an external standard and is shown in FIG. 3 of the accompanying drawings;
10) Solubility: Soluble in water and methanol, slightly soluble in acetone, and insoluble in ethyl acetate, chloroform and benzene;
11) Color reaction: Positive to ninhydrin, sulfuric acid, iodine, ferric chloride and Baeyer reactions;
12) Thin-layer chromatography:
Rf value; 0.36
Adsorbent; Silica gel plate (Merck, Kieselgel 60 F 254 )
Developing solvent: a 4:2:1 by volume mixture of butanol, propanol and water;
13) High performance liquid chromatography:
Column: Aquasil SS 372-N (Senshu Kagaku Co.)
Developing solvent; a 200:100:100:40 by volume mixture of chloroform, isopropanol, methanol and water;
Flow rate: 1 ml/minute;
Retention time; 3.92 minutes.
Mureidomycin B has the following physico-chemical properties:
1) Character and appearance: Amphoteric, soluble in water, white powder;
2) Specific rotation: [α] D 23 =-7° (c=0.3, 50% v/v aqueous methanol);
3) Elemental analysis: C, 50.67%; H, 6.36%; N, 12.62%; S, 3.13%--measured as the hydrate;
4) Molecular weight: 842 (high resolution mass spectrum), FAB MS: 843.33289 (QM + );
5) Molecular formula: C 38 H 50 N 8 O 12 S 1 ;
6) Products resulting from acid hydrolysis: Dihydrouracil, m-tyrosine, 2-amino-3-N-methylaminobutyric acid;
7) Ultraviolet absorption spectrum: λ max nm (E 1 cm 1% ) 255 nm (194) in neutral water; 255 nm (186) in 0.1N aqueous HCl; 245 nm (325) and 295 nm (85, shoulder) in 0.1N aqueous NaOH; the spectrum is shown in FIG. 7 of the accompanying drawings;
8) Infrared absorption spectrum (KBr) υ max cm -1 : the spectrum measured in a KBr disk is shown in FIG. 8 of the accompanying drawings;
9) Nuclear magnetic resonance spectrum, δ ppm: the spectrum (270 MHz) was measured in deuterium oxide using TMS as an external standard and is shown in FIG. 9 of the accompanying drawings;
10) Solubility: Soluble in water and methanol, slightly soluble in acetone and insoluble in ethyl acetate, chloroform and benzene;
11) Color reaction: Positive to ninhydrin, sulfuric acid, iodine, ferric chloride and Baeyer reactions;
12) Thin-layer chromatography:
Rf value; 0.34
Adsorbent; Silica gel plate (Merck, Kieselgel 60 F 254 )
Developing solvent; a 4:2:1 by volume mixture of butanol, propanol and water;
13) High performance liquid chromatography:
Column: Aquasil SS 372-N (Senshu Kagaku Co.)
Developing solvent; a 200:100:100:40 by volume mixture of chloroform, isopropanol, methanol and water
Flow rate: 1 ml/minute;
Retention time; 3.94 minutes.
Mureidomycin C has the following physico-chemical properties:
1) Character and appearance: Amphoteric, soluble in water, white powder;
2) Specific rotation: [α] D 25 =+16.7° (c=0.57, 50% v/v aqueous methanol);
3) Elemental analysis: C, 49.44%; H, 5.50%; N, 12.53%; S, 3.09%--measured as the hydrate;
4) Molecular weight: 897 (high resolution mass spectrum), FAB MS: 898.33687 (QM + );
5) Molecular formula: C 40 H 51 N 9 O 13 S 1 ;
6) Products resulting from acid hydrolysis: Uracil, glycine, m-tyrosine, 2-amino-3-N-methylaminobutyric acid;
7) Ultraviolet absorption spectrum: λ max nm (E 1 cm 1% ) 258 nm (292) in neutral water; 259 nm (312) in 0.01N aqueous HCl; 240 nm (444), 265 nm (276, shoulder) and 295 nm (72, shoulder) in 0.01N aqueous NaOH; the spectra are shown in FIGS. 4A and 4B of the accompanying drawings;
8) Infrared absorption spectrum (KBr) υ max cm -1 : the spectrum measured in a KBr disk is shown in FIG. 5 of the accompanying drawings;
9) Nuclear magnetic resonance spectrum, δ ppm: the spectrum (270 MHz) was measured in deuterium oxide using TMS as an external standard and is shown in FIG. 6 of the accompanying drawings;
10) Solubility: Soluble in water and methanol, slightly soluble in acetone, and insoluble in ethyl acetate, chloroform and benzene;
11) Color reaction: Positive to ninhydrin, sulfuric acid, iodine, ferric chloride and Baeyer reactions;
12) Thin-layer chromatography:
Rf value; 0.29
Absorbent; Silica gel plate (Merck, Kieselgel 60 F 254 )
Developing solvent; a 4:2:1 by volume mixture of butanol, propanol and water;
13) High performance liquid chromatography:
Column: Aquasil SS 372-N (Senshu Kagaku Co.)
Developing solvent; a 200:100:100:40 by volume mixture of chloroform, isopropanol, methanol and water
Flow rate: 1 ml/minute;
Retention time; 6.29 minutes.
Mureidomycin D has the following physico-chemical properties:
1) Character and appearance: Amphoteric, soluble in water, white powder;
2) Specific rotation: [α] D 23 =-30° (c=0.52, 50% v/v aqueous methanol);
3) Elemental analysis: C, 48.79%; H, 5.86%; N, 12.42%; S, 3.26%--measured as the hydrate;
4) Molecular weight: 899 (high resolution mass spectrum), FAB MS: 900.35617 (QM + );
5) Molecular formula: C 40 H 53 N 9 O 13 S 1 ;
6) Products resulting from acid hydrolysis: Dihydrouracil, glycine, m-tyrosine, 2-amino-3-N-methylaminobutyric acid;
7) Ultraviolet absorption spectrum: λ max nm (E 1 cm 1% ) 255 nm (191) in neutral water; 255 nm (184) in 0.1N aqueous HCl; 245 nm (346), and 295 nm (90, shoulder) in 0.1N aqueous NaOH; the spectrum is shown in FIG. 10 of the accompanying drawings;
8) Infrared absorption spectrum (KBr) υ max cm -1 : the spectrum measured in a KBr disk is shown in FIG. 11 of the accompanying drawings;
9) Nuclear magnetic resonance spectrum, δ ppm: the spectrum (270 MHz) was measured in deuterium oxide using TMS as an external standard and is shown in FIG. 12 of the accompanying drawings;
10) Solubility: Soluble in water and methanol, slightly soluble in acetone and insoluble in ethyl acetate, chloroform and benzene;
11) Color reaction: Positive to ninhydrin, sulfuric acid, iodine, ferric chloride and Baeyer reactions;
12) Thin-layer chromatography:
Rf value; 0.26
Adsorbent; Silica gel plate (Merck, Kieselgel 60 F 254 )
Developing solvent; a 4:2:1 by volume mixture of butanol, propanol and water;
13) High performance liquid chromatography:
Column: Aquasil SS 372-N (Senshu Kagaku Co.)
Developing solvent; a 200:100:100:40 by volume mixture of chloroform, isopropanol, methanol and water
Flow rate: 1 ml/minute;
Retention time; 7.24 minutes.
The invention also provides pharmaceutically acceptable salts and esters of the above compounds.
The invention also provides a process for producing mureidomycin A, B, C or D and salts and esters thereof by cultivating a mureidomycin A, B, C or D-producing microorganism of the genus Streptomyces in a culture medium therefor and isolating mureidomycin A, B, C or D or a salt thereof from the cultured broth and optionally salifying, desalifying or esterifying the compound thus isolated.
The invention still further provides a pharmaceutical composition comprising such a mureidomycin A, B, C or D or a salt or ester thereof in admixture with a pharmaceutically acceptable carrier or diluent.
The invention still further provides a method for the treatment or prophylaxis of bacterial infections by administering such a mureidomycin A, B, C or D or a salt or ester thereof to an animal, which may be human or non-human.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows the ultraviolet absorption spectrum of mureidomycin A;
FIG. 2 shows the infrared absorption spectrum of mureidomycin A;
FIG. 3 shows the nuclear magnetic resonance spectrum of mureidomycin A;
FIG. 4 shows the ultraviolet absorption spectrum of mureidomycin C;
FIG. 5 shows the infrared absorption spectrum of mureidomycin C;
FIG. 6 shows the nuclear magnetic resonance spectrum of mureidomycin C;
FIG. 7 shows the ultraviolet absorption spectrum of mureidomycin B;
FIG. 8 shows the infrared absorption spectrum of mureidomycin B;
FIG. 9 shows the nuclear magnetic resonance spectrum of mureidomycin B;
FIG. 10 shows the ultraviolet absorption spectrum of mureidomycin D;
FIG. 11 shows the infrared absorption spectrum of mureidomycin D; and
FIG. 12 shows the nuclear magnetic resonance spectrum of mureidomycin D.
DETAILED DESCRIPTION OF INVENTION
Mureidomycins A, B, C and D and salts thereof are produced by the cultivation of a Streptomyces strain herein identified as Streptomyces sp. SANK 60486, and which has the following mycological properties. These characteristics were determined by cultivation on various media prescribed by the ISP (International Streptomyces Project) or with the media recommended by S. A. Waksman in Volume 2 of "The Actinomycetes", in all cases at a temperature of 28° C., except where otherwise stated.
1. MORPHOLOGICAL CHARACTERISTICS
Generally, on an agar medium, the substrate hyphae of the microorganism branch and elongate well and the aerial hyphae of the microorganism branch simply. The spore chain forms straight to curved lines. It is observed that the number of spores formed on a spore chain are mostly from ten to fifty, but may be more. The spores are elliptoidal and in size range from 0.5-0.8 μm×0.7-1.1 μm; they have a smooth surface. No special organs, such as wheel axle branching of the aerial hyphae, sclerotia, sporangia and the like, were observed.
2. CULTURE CHARACTERISTICS
After culturing on various kinds of culture media at 28° C. for 14 days, the properties are shown in Table 1. Representation of the color tones is shown by using the color tip numbers given in the "Guide to Color Standard" edited by Nippon Shikisai Kenkyusho.
In this Table, the following abbreviations are used: G: growth; AM: aerial mycelium; R: reverse; SP: soluble pigment.
TABLE 1______________________________________Culture medium Item Properties of SANK 60486______________________________________Sucrose nitrate G Limited, flat, yellowishagar grey (1-9-10) AM Well formed, powdery, yellowish grey (1-9-10) R Pale yellowish orange (2-9-9) SP Not producedGlucose asparagine G Good, flat, light brownagar (2-8-9) AM Well formed, powdery, pale yellowish orange (2-9-9) R Yellowish brown (4-7-9) SP Not producedGlycerin asparagine G Good, protuberant, paleagar yellowish orange (2-7-9)(ISP 5) AM Plentiful, powdery, pale yellowish orange (2-9-9) R Yellowish brown (4-7-9) SP Not producedStarch inorganic salt G Very good, flat, paleagar yellowish brown (4-8-9)(ISP 4) AM Plentiful, powdery, pale yellowish orange (2-9-9) R Pale yellowish brown (4-8-9) SP Not producedTyrosine agar G Very good, flat, bright(ISP 2) brownish grey (2-8-8) AM Plentiful. powdery, brownish white (1-8-6) R Yellowish brown (4-7-9) SP Not producedPeptone yeast G Very good. rumpled, paleextract iron agar yellowish brown (4-8-9)(ISP 6) AM Slightly formed, white R Pale yellowish brown (6-7-9) SP Not producedNutrient agar G Very good, flat, pale(Difco) yellowish orange (2-9-9) AM Well formed, powdery, white R Pale yellowish orange (2-9-9) SP Not producedYeast germ wheat G Very good, flat, paleagar yellowish brown (4-8-9)(ISP 2) AM Plentiful, powdery, yellowish grey (2-8-10) R Yellowish brown (8-6-9) SP Not producedOatmeal agar G Good, flat, yellowish grey(ISP 3) (1-9-10) AM Plentiful, powdery, yellowish grey (1-9-10) R Pale yellowish brown (6-7-9) SP Pale yellowish brown (4-7-8 slightly)Water agar G Limited, flat, yellowish grey (1-9-10) AM Limited, powdery, white R Pale yellowish orange (2-9-9) SP Not producedPotato extract G Limited, flat, palecarrot extract agar yellowish orange (2-9-9) AM Well formed, powdery, pale yellowish orange (2-9-9) R Pale yellowish orange (2-9-9) SP Not produced______________________________________
3. PHYSIOLOGICAL PROPERTIES
The physiological properties of strain SANK 60486 are shown in Table 2.
TABLE 2______________________________________Hydrolysis of starch PositiveLiquefaction of gelatin PositiveReduction of nitrate salt PositiveCoagulation of milk PositivePeptonization of milk PositiveTemperature range of growth 6-34° C.(culture medium 1)*Sodium chloride resistance Growth(culture medium 1)* in 7%, no growth in 10%Decomposition of casein PositiveDecomposition of tyrosine PositiveDecomposition of xanthine NegativeProductivity of melanin-like pigment(culture medium 2)* Negative(culture medium 3)* Negative(culture medium 4)* Negative______________________________________ *Culture medium 1; yeast germ wheat agar (ISP 2); *Culture medium 2; tryptone yeast extract broth (ISP 1); *Culture medium 3; peptone yeast extract iron agar (ISP 6); *Culture medium 4; tyrosine agar (ISP 7).
After culturing on Pridham Gottlieb agar medium (ISP 9) at 28° C. for 14 days, assimilability of carbon sources by strain SANK 60486 is shown in Table 3.
TABLE 3______________________________________ .sub.-- D-Glucose + .sub.-- L-Arabinose + .sub.-- D-Xylose + Inositol - .sub.-- D-Mannitol + .sub.-- D-Fructose + .sub.-- L-Rhamnose + Sucrose - Raffinose - Control -______________________________________ In the above Table: + assimilable; - not assimilable.
4. CELL WALL CONSTITUTION
The cell wall of strain SANK 60486 was examined according to the method of B. Becker et al. [Applied Microbiology, 12, 421-423 (1964)]. L,L-Diaminopimelic acid and glycine were detected in it.
Identification of strain SANK 60486 was carried out in accordance with The International Streptomyces Project; Bergey's Manual of Determinative Bacteriology, 8th edition; "The Actinomycetes" edited by S. A. Waksman and other recent literature relating to the Streptomycetes.
On the basis of the above data, the strain was identified as a strain of Streptomyces flavidovirens and is here referred to as Streptomyces flavidovirens SANK 60486 (FERM P-8636).
The strain SANK 60486 has been deposited with the Fermentation Research Institute, Agency of Industrial Science and Technology, Ministry of International Trade and Industry, Japan, on Feb. 4, 1986 under the accession No. FERM P-8636 and was re-deposited in accordance with the conditions stipulated by the Budapest Treaty with said Fermentation Research Institute on Apr. 17, 1987 under the accession No. FERM BP-1347.
It has been established that strain SANK 60486 produces mureidomycins A, B, C and D. However, as is well known, the properties of microorganisms falling within the general category of the actinomycetes can vary considerably and such microorganisms can readily undergo mutation, both through natural causes and as the result of induction by artificial means. Accordingly, the process of the present invention embraces the use of any microorganism which can be classified within the genus Streptomyces and which shares with the strain SANK 60486 the characteristic ability to produce mureidomycins A, B, C and D.
The microorganism employed in the process of the present invention is preferably a strain of the species Streptomyces flavidovirens, and more preferably Streptomyces flavidovirens SANK 60486 (FERM P-8636).
The cultivation of microorganisms of the genus Streptomyces in accordance with the present invention to produce mureidomycins A, B, C and D can be performed under conditions conventionally employed for the cultivation of actinomycetes species, preferably in a liquid culture, and desirably with shaking or stirring and aeration. The nutrient medium used for the cultivation is completely conventional and contains such constituents as are commonly used in the cultivation of the actinomycetes. Specifically, the medium should contain one or more assimilable carbon sources, suitable examples of which include glucose, maltose, sucrose, mannitol, molasses, glycerol, dextrin, starch, soybean oil and cottonseed oil; one or more assimilable nitrogen sources, suitable examples of which include soybean meal, peanut meal, cottonseed meal, pharmamine, fish meal, corn steep liquor, peptone, meat extract, live yeast, pressed yeast, yeast extract, sodium nitrate, ammonium nitrate or ammonium sulfate; and one or more inorganic salts, such as sodium chloride, phosphates, calcium carbonate and trace metal salts. Where cultivation is effected in a liquid medium, it is generally desirable to incorporate an anti-foaming agent (for example, silicone oil, vegetable oil or a suitable surfactant) in the medium.
The cultivation is suitably performed at a substantially neutral pH value and at a temperature of from 20° to 37° C., more preferably at about 22° C.
The production of mureidomycins A, B, C and D as cultivation proceeds may be monitored by a variety of conventional microbiological assay techniques for monitoring the production of antibiotics (when they are produced by microbial culture) and which require little or no elaboration here. A suitable technique might be the paper disc-agar diffusion assay (using, for example, a paper disc of diameter about 8 mm produced by Toyo Kagaku Sangyo Co., Ltd) and using, for example, Pseudomonas aeruginosa as the test organism.
The amount of mureidomycins A, B, C and D produced normally reaches a maximum after cultivation has proceeded for 72-96 hours and it is clearly desirable to separate the mureidomycins from the culture medium no later than the time when this maximum has been reached. However, this period may vary, depending upon the cultivation conditions and techniques, and a shorter or longer period may be appropriate, depending upon the circumstances. The correct cultivation time may readily be assessed for every case by routine experiment, using suitable monitoring techniques, e.g., as described above.
Mureidomycins A, B, C and D are mainly released into the liquid portion of the cultured broth and can thus be recovered by removing solid matter, including the mycelium, for example, by filtration (preferably using a filter aid such as diatomaceous earth) or by centrifugation. They can then be recovered from the separated liquid portion by conventional techniques and, if desired, then purified and/or separated from each other.
The antibiotics, mureidomycins A, B, C and D, may be separated, collected and purified by utilizing their physico-chemical properties. For example, suitable methods include: extraction with solvents; ion-exchange through resins, for example, anion exchange resins such as Dowex SBR-P (Dow Chemical Co.) or cation exchange resins such as Dowex 50 W (Dow Chemical Co.) or IRC-50, CG-50 (Rohm & Haas Co.); chromatography through active carbon as the absorbent or through non-ionic absorption resins such as Amberlite XAD-2, XAD-4 or XAD-7 (Rohm and Hass Co.) or Diaion HP 10, HP 20, CHP 20P or HP 50 (Mitsubishi Chemical Industries, Ltd.); and chromatography through silica gel or alumina. Furthermore, separation, collection and purification of the metabolites may be performed by using any one or more of the following operations, which may be combined in any order or repeated, if desired: partition column chromatography over cellulose such as Avicel (Asahi Chemical Industry Co., Ltd.) or Sephadex LH-20 (Pharmacia Co.); gel filtration using Sephadex G-10, G-25, G-50 or G-100 (Pharmacia Co.) or Toyopearl HW-40 (Toyo Soda MFG Co., Ltd.); crystallization; and recrystallization. "Dowex", "Amberlite", "Diaion", "Avicel", "Sephadex" and "Toyopearl" are all trade marks.
Depending upon the culture conditions, mureidomycins A, B, C and D can exist in the mycelium from the culture broth and can be extracted therefrom by conventional techniques. For example, they can be extracted with a hydrophilic organic solvent (such as an alcohol or acetone), and then the solvent removed from the extract to leave a residue, which is dissolved in an aqueous medium. The mureidomycins can be extracted from the resulting solution and purified as described above.
Mureidomycins A, B, C and D are preferably separated from each other by chromatography.
Mureidomycins A, B, C and D thus obtained have the physical and chemical properties described above.
Since mureidomycins A, B, C and D are amphoteric in character, they form salts and esters and these salts and esters also form part of the present invention. The nature of such salts and esters is not critical, except that, where they are to be used for medicinal or veterinary purposes, they must be medicinally acceptable, i.e. they must not, or must not to a significant extent, either have increased toxicity or have reduced activity, as compared with the free unsalified or unesterified compound.
Examples of suitable acids for the formation of such salts include: inorganic acids, such as hydrochloric acid, sulfuric acid or phosphoric acid; organic carboxylic acids, such as acetic acid, citric acid, tartaric acid, malonic acid, maleic acid, malic acid, furmaric acid, itaconic acid, citraconic acid or succinic acid; and organic sulfonic acids, such as methanesulfonic acid, benzenesulfonic acid, naphthalenesulfonic acid or p-toluenesulfonic acid.
Examples of suitable esters include: C 1 -C 6 , more preferably C 1 -C 4 , alkyl esters, for example the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, t-butyl, pentyl and hexyl esters; aralkyl and diarylalkyl esters, such as the benzyl, p-nitrobenzyl and benzhydryl esters; alkoxycarbonylalkyl esters, in which the alkoxy and alkyl parts are both C 1 -C 4 , especially alkoxycarbonylmethyl esters, such as the ethoxycarbonylmethyl and t-butoxycarbonylmethyl esters; alkoxycarbonyloxyalkyl esters in which the alkoxy and alkyl parts are both C 1 -C 4 , especially 2-(alkoxycarbonyloxy)ethyl esters, such as the 2-methoxycarbonyloxyethyl, 2-ethoxycarbonyloxyethyl and 2-t-butoxycarbonyloxyethyl esters; and other specific esters, such as the phthalidyl, substituted phthalidyl, phenacyl, substituted phenacyl (e.g. p-nitrophenacyl) and (5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl esters. The esters are preferably formed at the carboxy group.
The carboxy group may also form salts with appropriate bases. The nature of such salts is likewise not critical, provided that, where they are to be used for therapeutic purposes, the salts are pharmaceutically acceptable. Examples of salts with base include: salts with metals, especially alkali metals and alkaline earth metals, such as the lithium, sodium, potassium, calcium and magnesium salts; the ammonium salt; salts with organic amines, such as cyclohexylamine, diisopropylamine or triethylamine; and salts with basic amino acids, such as lysine or arginine.
Where the mureidomycin A, B, C or D is isolated in the form of a salt, it may be converted to the free unsalified compound by conventional means, such as the use of ion-exchange resins or of adsorbents for reverse phase chromatography. Equally, the free unsalified compound may be salified by conventional means. Esters may be prepared by conventional esterification procedures.
The minimal inhibitory concentrations (MIC) of mureidomycins A, B, C and D against various gram-positive and gram-negative bacteria were determined by the two-fold agar dilution method, using a Mueller-Hinton agar medium (produced by Difco). The results are shown in Table 4.
TABLE 4______________________________________ MIC (μg/ml)Tested MureidomycinBacterium A B C D______________________________________Staphylo- 200 >200 >200 >200coccusaureusFDA 209PJC-1.sbsp.Esherichia >200 >200 >200 >200coliNIHJ JC-2Proteus >200 >200 >200 >200mirabilisSANK 70461Klebsiella 25 25 12.5 25pneumoniaePCI 602Pseudomonas >200 200 >200 100acidovoransSANK 72782Pseudomonas 6.25 25 1.56 6.25aeruginosaSANK 71873Pseudomonas 6.25 200 1.56 6.25aeruginosaSANK 75775Pseudomonas 25 50 3.13 12.5aeruginosaSANK 75175Pseudomonas 12.5 25 1.56 3.13aeruginosaSANK 70970Pseudomonas 12.5 25 1.56 6.25aeruginosaSANK 73279Pseudomonas 100 200 6.25 50aeruginosaSANK 73379Pseudomonas 25 50 3.13 6.25aeruginosaNRRLB 1000Pseudomonas 25 50 3.13 6.25aeruginosaATCC 13388Pseudomonas 6.25 12.5 1.56 6.25aeruginosaSANK 70479Pseudomonas <0.1 0.2 <0.1 0.2aeruginosaSANK 70579Pseudomonas 12.5 25 3.13 6.25aeruginosaSANK 73375Pseudomonas 0.4 0.8 0.4 1.56aeruginosaNCTC 10490Serratia >200 >200 >200 >200marcescensSANK 73060______________________________________
From the above data, mureidomycins A, B, C and D are active against gram-negative bacteria, particularly against bacteria of the genus Pseudomonas.
No toxicity was observed in mice receiving 400 mg/kg of mureidomycins A, B, C or D intravenously.
From the above findings, it can be seen that mureidomycins A, B, C and D can be used as antibiotics against various diseases caused by bacterial infections. The route of administration can vary widely and may be parenteral (e.g., by subcutaneous, intravenous or intramuscular injection or by suppository) or oral (in which case it may be administered in the form of a tablet, capsule, powder or granule). The dose will, of course, vary with the nature of the disease to be treated, the age, condition and body weight of the patient and the route and time of administration; however, for an adult human patient, a daily dose of from 0.1 to 10 grams is preferred and this may be administered in a single dose or in divided doses.
The invention is further illustrated by the following examples.
EXAMPLE 1
PREPARATION OF ACTIVE METABOLITE
One platinum loopful growth of Streptomyces flavidovirens SANK 60486 was inoculated into a 500 ml Erlenmeyer flask containing 80 ml of medium A, which has the following composition (percentages are by weight):
______________________________________MEDIUM A______________________________________Glucose 3%Pressed yeast 1%Soybean meal 3%Calcium carbonate 0.4%Magnesium sulfate heptahydrate 0.2%Anti-foaming agent 0.01%(Nissan Disfoam CB-442)Water the balance(pH 7.2 before sterilization)______________________________________
The microorganism was then cultured for 84 hours at 22° C., using a rotary shaker at 220 r.p.m.
25 ml of the resulting seed culture were inoculated into each of four 2-liter Erlenmeyer flasks, each containing 500 ml of medium A, which has the composition described above. The microorganism was then cultured at 22° C. for 24 hours, using a rotary shaker at 220 r.p.m.
The resulting cultured broths were combined. 750 ml of this broth were then inoculated into each of two 30 liter jar fermentors, each containing 15 liters of medium A, and the microorganism was then cultured at 22° C. for 96 hours, whilst aerating at the rate of 15 liters per minute and agitating at 150 r.p.m.
At the end of this time, batches of cultured broth separately cultivated as described above were combined to give a total of 30 liters of cultured broth. Celite 545 (a registered trade mark for a product of Johns-Manville Products Corp, New Jersey, U.S.A.) filter aid was added to the cultured broth and the mixture was filtered, to give 30 liters of a filtrate. This filtrate was adsorbed on 3 liters of Amberlite XAD-2 in a chromatography column. The column was washed, in turn, with 15 liters of purified water and then with 12 liters of water containing 15% v/v methanol, after which it was eluted with 15 liters of water containing 40% v/v methanol. The methanol was then removed from the fractions containing active components by distillation under reduced pressure, after which the residual solution was lyophilized, to give 17.4 g of a crude product as a powder.
17 g of this crude powder were dissolved in 3 liters of purified water, and the solution was passed through a column containing 800 ml of Amberlite CG-50 (H + ), to adsorb the active component. The active component was eluted from the column with 0.5M aqueous ammonia. The eluted active fractions (3.5 liters) were collected and concentrated to a volume of 1.0 liter by evaporation under reduced pressure. The concentrate (1.0 liter) was passed through 400 ml of DE-52 ion exchanger (Whatman Ltd.), which had been pre-equilibrated with a 0.1M aqueous solution of ammonium bicarbonate and the active component was adsorbed on the column. The column was eluted with 0.2M aqueous ammonium bicarbonate. The fractions (800 ml) containing the active component were collected and adsorbed on a column containing 200 ml of Diaion HP 20 (Mitsubishi Chemical Industries, Ltd.), after which the column was eluted with 500 ml of 50% v/v aqueous acetone, to give an active component. The fractions containing the active component were concentrated by evaporation under reduced pressure and lyophilized to afford 1.6 g of a crude powdery product containing mureidomycins A, B, C and D.
1.5 g of this crude powder was dissolved in 200 ml of purified water, and the active component was adsorbed on a column containing 500 ml of DE-52 which had been pre-equilibrated with 0.05M aqueous ammonium bicarbonate. The column was washed with 0.05M aqueous ammonium bicarbonate, and then eluted with 0.1M aqueous ammonium bicarbonate, to give fractions, each containing 20 ml of the eluent.
EXAMPLE 2
SEPARATION OF MUREIDOMYCINS A AND C
Fractions No. 80 to 130, from the fractionation described at the end of Example 1, were collected and were adsorbed on a column of Diaion HP 20 in order to desalt them. The desalted eluent was concentrated by evaporation under reduced pressure, and the residue was lyophilized to give 309 mg of a partially purified product, containing mureidomycins A and C, as a powder. 300 mg of this partially purified powder were then subjected to column chromatography through 100 g of silica gel, which was then eluted with a 8:4:1 by volume mixture of butanol, propanol and water, to give fractions, each containing 20 ml of the eluent. The chromatogram showed two peaks due to the presence of two active components.
Fractions No. 13 to 36 were collected, mixed with water and then concentrated by evaporation under reduced pressure and lyophilized to give 33 mg of crude mureidomycin A as a powder.
In a similar manner, 66 mg of crude mureidomycin C were isolated from fractions No. 56 to 75.
EXAMPLE 3
PREPARATION AND PURIFICATION OF MUREIDOMYCIN A
A solution of 30 mg of crude mureidomycin A (prepared as described in Example 2) dissolved in 30% v/v aqueous methanol was adsorbed on a column containing 1000 ml of Toyopearl HW-40, and the column was eluted with 30% v/v aqueous methanol to give fractions, each containing 10 ml of the eluent. Fractions No. 50 to 70 were collected as active fractions, and these were adsorbed on a column containing 10 ml of Amberlite CG50 (H + type), which was then eluted with 0.5M aqueous ammonia. The fractions containing active components were collected, concentrated by evaporation under reduced pressure and lyophilized to afford 24 mg of mureidomycin A having the properties defined above.
EXAMPLE 4
PREPARATION AND PURIFICATION OF MUREIDOMYCIN C
A solution of 60 mg of crude mureidomycin C (prepared as described in Example 2) dissolved in 30% v/v aqueous methanol was adsorbed on a column containing 1000 ml of Toyopearl HW-40, and the column was eluted with 30% v/v aqueous methanol to give fractions, each containing 10 ml of the eluent. Fractions No. 65 to 85 were collected as active fractions, and these were adsorbed on a column containing 10 ml of Amberlite CG50 (H + type), which was then eluted with 0.5M aqueous ammonia. The active fractions were collected, concentrated by evaporation under reduced pressure and lyophilized to afford 49 mg of mureidomycin C having the properties defined above.
EXAMPLE 5
SEPARATION OF MUREIDOMYCINS B AND D
Fractions No. 25 to 60, from the fractionation described at the end of Example 1, were collected and were adsorbed on a column of Diaion HP 20 in order to desalt them. The desalted eluent was concentrated by evaporation under reduced pressure, and the residue was lyophilized to give 510 mg of a partially purified product, containing mureidomycins B and D, as a powder.
500 mg of this partially purified powder were subjected to column chromatography through 100 g of silica gel, after which it was eluted with a 8:4:1 by volume mixture of butanol, propanol and water, to give fractions, each containing 20 ml of the eluent. The chromatogram showed two peaks due to the presence of two active components. Fractions No. 37 to 55 were collected, mixed with water and then concentrated by evaporation under reduced pressure and lyophilized to give 74 mg of crude mureidomycin B as a powder. In a similar manner, 67.5 mg of crude mureidomycin D were isolated from fractions No. 76 to 110.
EXAMPLE 6
PREPARATION AND PURIFICATION OF MUREIDOMYCIN B
A solution of 70 mg of crude mureidomycin B (prepared as described in Example 5) dissolved in 30% v/v aqueous methanol was adsorbed on a column containing 1000 ml of Toyopearl HW-40, and the column was eluted with 30% v/v aqueous methanol to give fractions, each containing 10 ml of the eluent. Fractions No. 55 to 75 were collected as active fractions, and these were adsorbed on a column containing 10 ml of Amberlite CG50 (H + type) and eluted with 0.5M aqueous ammonia. The fractions containing active components were collected, concentrated by evaporation under reduced pressure and lyophilized to afford 45 mg of mureidomycin B having the properties defined above.
EXAMPLE 7
PREPARATION AND PURIFICATION OF MUREIDOMYCIN D
A solution of 65 mg of crude mureidomycin D (prepared as described in Example 5) dissolved in 30% v/v aqueous methanol was adsorbed on a column containing 1000 ml of Toyopearl HW-40, and the column was eluted with 30% v/v aqueous methanol to give fractions, each containing 10 ml of the eluent. Fractions No. 65 to 85 were collected as active fractions, and these were then adsorbed on a column containing 10 ml of Amberlite CG50 (H + type) and eluted with 0.5M aqueous ammonia. The fractions were collected, concentrated by evaporation under reduced pressure and lyophilized to afford 40 mg of mureidomycin D having the properties defined above.
EXAMPLE 8
CAPSULES FOR ORAL ADMINISTRATION
The following powders were mixed:
______________________________________Mureidomycin A 100 mgLactose 100 mgMaize starch 148.5 mgMagnesium stearate 1.5 mg 350 mg______________________________________
and passed through a 30-mesh sieve (Tyler standard). The mixture (350 mg) was sealed into a gelatin capsule No. 2 to yield the desired capsule.
EXAMPLE 9
CAPSULES FOR ORAL ADMINISTRATION
The following powders were mixed:
______________________________________Mureidomycin C 100 mgLactose 100 mgMaize starch 148.5 mgMagnesium stearate 1.5 mg 350 mg______________________________________
and passed through a 30-mesh sieve (Tyler standard). The mixture (350 mg) was sealed into a gelatin capsule No. 2 to yield the desired capsule.
EXAMPLE 10
INJECTION
1.0 g of mureidomycin A was dissolved in 5.0 ml of a 1/15M phosphate buffer solution and the solution was sealed into a 5 ml ampoule. The ampoule was sterilized by a conventional procedure to yield the desired injectible liquid.
EXAMPLE 11
INJECTION
1.0 g of mureidomycin C was dissolved in 5.0 ml of a 1/15M phosphate buffer solution and the solution was sealed into a 5 ml ampoule. The ampoule was sterilized by a conventional procedure to yield the desired injectible liquid.
EXAMPLE 12
CAPSULES FOR ORAL ADMINISTRATION
The following powders were mixed:
______________________________________Mureidomycin B 100 mgLactose 100 mgMaize starch 148.5 mgMagnesium stearate 1.5 mg 350 mg______________________________________
and passed through a 30-mesh sieve (Tyler standard). The mixture (350 mg) was sealed into a gelatin capsule No. 2 to yield the desired capsule.
EXAMPLE 13
CAPSULES FOR ORAL ADMINISTRATION
The following powders were mixed:
______________________________________Mureidomycin D 100 mgLactose 100 mgMaize starch 148.5 mgMagnesium stearate 1.5 mg 350 mg______________________________________
and passed through a 30-mesh sieve (Tyler standard). The mixture (350 mg) was sealed into a gelatin capsule No. 2 to yield the desired capsule.
EXAMPLE 14
INJECTION
1.0 g of mureidomycin B was dissolved in 5.0 ml of a 1/15M phosphate buffer solution and the solution was sealed into a 5 ml ampoule. The ampoule was sterilized by a conventional procedure to yield the desired injectible liquid.
EXAMPLE 15
INJECTION
1.0 g of mureidomycin D was dissolved in 5.0 ml of a 1/15M phosphate buffer solution and the solution was sealed into a 5 ml ampoule. The ampoule was sterilized by a conventional procedure to yield the desired injectible liquid. | Novel compounds, called mureidomycins A, B, C and D, may be prepared by cultivation of a suitable microorganism of the genus Streptomyces, especially Streptomyces flavidovirens SANK 60486 (FERM P-8636, FERM BP-1347). These represent a wholly new class of antibiotics, which are valuable in the treatment of infections caused by a variety of bacteria, notably of the genus Pseudomonas. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is directed generally to a heater apparatus, such as an auxiliary heater for a motor vehicle including one wall of a heat exchanger for separating a heated flammable gas or exhaust gas from a heat exchange medium, a conveyor mechanism for conveying the heat exchange medium along the wall, and a protective mechanism for protecting the heater from overheating. The invention further relates to a process for operating such a heater including the use of a hot-wire anemometer for measuring the hot air mass flow in the heater.
2. Description of the Related Art
Heater apparatus which are used as air heaters for heating hot air in a passenger compartment of a motor vehicle use fresh air and/or circulating air from the passenger compartment as the heat exchange medium. The hot air flow from the heat exchange medium absorbs the heat energy released by the heated exhaust gas to the wall of a heat exchanger and delivers the heat to the passenger compartment. When a passenger closes a flap or the exit openings of the passenger compartment heating system in order to limit the heat output from the heater, the hot air flow from the heater is reduced such that the heat exchange medium can no longer dissipate the heat energy of the flammable gas. Such a case is commonly referred to as “damming.” In such a case, the temperature of the heat exchanger wall increases quickly, and results in the wall becoming leaky and can burn through. If this occurs, there is no longer separation between the exhaust gas and the heat exchange medium, and, in extreme cases, the exhaust can reach the passenger compartment.
In order to reliably prevent the dangerous mixing of the exhaust gas and the hot air flow, attempts have been, in the case of damming of the heater on the hot air outlet side, to promptly and reliably detect the danger of overheating of the wall of the heat exchanger, in order to then turn down or turn off the heater. Published German Patent Application DE 35 17 954 A1 discloses a generic auxiliary motor vehicle heater with a heat exchanger through which a heat exchange medium flows. In order to protect the heater from overheating, two sensors for sensing temperature are provided at the inlet and the outlet of the heat exchanger, the sensors being interconnected for monitoring of the operating state of the heater. The arrangement of two temperature sensors is, however, expensive and maintenance-intensive.
German Patent Publication DE 43 11 080 C1 discloses a motor vehicle heater which is independent of the engine and includes a flame monitor and one temperature sensor adjoining the wall of a heat exchanger for protecting the heat from overheating. Published German Patent Application DE 44 33 210 A1 discloses an auxiliary motor vehicle heater with a heat exchanger in which a temperature sensor is mounted between the combustion chamber and the exit opening of the heat exchange medium such that the sensor is used both as a mechanism protecting against overheating and as a flame monitor.
Temperature sensors for these applications generally have a resistance which can changed depending on temperature, for example, with a PTC characteristic. One disadvantage associated with this is that the shut-off of a PTC temperature sensor is comparatively slow and can only take place at a temperature above the full load temperature of the wall. For example, a full load temperature of 220° C. is conventional, while a shutoff temperature is typically 250° C. Therefore, under certain circumstances, the wall is heavily thermally loaded so that it must have a high wall thickness and other complex structural measures are necessary. Furthermore, to achieve the shutoff temperature, fuel is additionally consumed, with which the efficiency of the heater deteriorates.
Published German Patent Application DE 198 02 906 A1 discloses a fuel-operated air heater for motor vehicles with a burner and a heat exchanger by which hot air serves as the heat exchange medium and is conveyed by a fan, and flame monitor and an overheating sensor on the burner. The overheating sensor is an unencapsulated hot air temperature sensor, i.e., the sensor is located in the hot air flow without contact with the wall, especially in the area of the heat exchanger near the fan. Under certain circumstances, the measurement of the hot air temperature is too slow to reliably preclude overheating of the wall of the heat exchanger. This is due to the fact that when the hot air delivery is dammed, the temperature of the hot air rises very quickly and directly on the wall, but the temperature of the hot air rises more slowly farther away from the wall, for example at the site of the hot air temperature sensor.
Published German Patent Application DE 44 47 286 A1 discloses a motor vehicle heater with a burner (which is supplied by a fuel metering pump) and a combustion air fan. Depending upon the delivered amount of fuel, in order to achieve optimum combustion in the burner, a theoretical combustion air mass flow is determined and then compared to the actual combustion air mass flow. The speed of the combustion air fan is adjusted such that the actual value corresponds to the theoretical value. A combustion air mass flowmeter such as a hot-wire anemometer is placed in the combustion air channel in order to determine the actual combustion air mass flow. These combustion air mass flowmeters are known and are used in the control of combustion in the intake lines of internal combustion engines.
SUMMARY OF THE INVENTION
The object of the invention is to improve a heater of the initially-mentioned type such that the aforementioned disadvantages are surmounted, and especially, the danger of overheating the heater is recognized more reliably when the heat exchange medium delivery is dammed.
This object is achieved in accordance with the invention in that the protective mechanism of a heater of the initially-mentioned type is provided to determine during operation the mass flow of the heat exchange medium delivered by the conveyor mechanism.
The object is furthermore achieved with a process for controlling one such heater in which the protective mechanism, when the heater is activated, determines the mass flow of the heat exchange medium delivered by the conveyor mechanism, then compares the mass flow to the theoretical mass flow of the heat exchange medium stored in the protection mechanism, and at a difference between the current mass flow of the heat exchange medium and the theoretical mass flow of the heat exchange medium which indicates the danger of overheating the heat exchanger, limits the production of heated flammable gas in the heater.
The essence of the invention is that in order to detect the danger of overheating of the heat exchanger, the temperatures are not determined, as is the case in the related art which measures the temperature of the wall of the heat exchanger or the hot air as the heat exchange medium, but another physical quantity, specifically, the mass flow of the heat exchange medium, is determined. When the heat exchange medium inlet or the heat exchange medium outlet is dammed, the conveyor mechanism does not deliver the heat exchange medium in a sufficiently large amount through the heat exchanger, so that the mass flow of the heat exchange medium becomes zero or almost zero. This reduction in mass flow of the heat exchange medium is detected in accordance with the invention by the protective mechanism, and thus, the danger of overheating the heater is detected. The reduction of mass flow of the heat exchange medium occurs immediately upon damming so that the danger of overheating is detected without a skew. The heater in accordance with the invention can, therefore, be turned down or off especially quickly.
Another advantage of the invention is that the wall of the heat exchanger need not be heated beyond the full load temperature. The danger of damage to the wall or other components of the heater is, therefore, eliminated and additional fuel consumption is prevented. In addition, in the heater in accordance with the invention, the protection mechanism immediately and reliably detects failure of the conveyor for the heat exchange medium.
In one advantageous embodiment of the invention, the protective mechanism has a heat exchange medium mass flowmeter which is located in the hot air delivery line. A heat exchange medium mass flowmeter can be economically ordered as a standard component and is offered in various embodiments so that it can be easily incorporated electrically into an existing heater and its control. The heat exchange medium mass flowmeter is located advantageously in the conveyor line between the conveyor mechanism and the heat exchanger. In this section of the conveyor line, the heat exchange medium mass flowmeter can be installed easily since it does not require integration into the heat exchanger. The reaction time of the heat exchange medium mass flowmeter is especially short when it is located on the pressure side of the conveyor mechanism.
Another embodiment of the invention is that the heater includes a burner and the protective mechanism has a control device which is operationally coupled to the burner and the heat exchange medium mass flowmeter. The control device is provided to compare the acquired actual heat exchange medium mass flow to a theoretical heat exchange medium mass flow, and subsequently controls the burner depending upon the comparison, for example, by reducing output from burner or deactivating the burner. The proposed control is based solely on an actual-theoretical comparison, and, can therefore, be done by the control which is present in conventional heaters.
The function of the protective mechanism in accordance with the invention is expanded almost without additional cost by providing the control device with a nonvolatile storage in which, for the theoretical heat exchange medium mass flow, at least one tolerance range is filed which is assigned to one load state of the heater, especially a full load or at least a partial load. Preferably, the theoretical heat exchange medium mass flow values are stored for each load state of the heater. As long as the measured mass flow of the heat exchange medium and thus the delivery performance of the conveyor means is above the lower boundary of the tolerance range, sufficient flow of the heat exchange medium mass through the heat exchanger is ensured. As previously explained, the heat exchanger is protected against overheating. The upper boundary of the tolerance range ensures that the mass flow of the heat exchange medium is not unduly large. This could be the case when control of the conveyor mechanism or of the burner of the heater is defective or the load states of the burner and conveyor mechanism of the heat exchange medium are poorly tuned to one another. If during a certain unit of time relative to the load state of the burner, too much heat exchange medium mass is conveyed by the heat exchange medium, the heat exchange medium mass cannot be heated to the required extent and therefore does not yield the desired heat output in the passenger compartment.
In another embodiment of the invention which is especially well suited for heaters of motor vehicles, the heat exchange medium is air and the heat exchange medium mass flowmeter is a hot-wire anemometer. Mass flowmeters are already used in motor vehicles for controlling combustion in intake lines of internal combustion engines, and, therefore, are especially economical with respect to procurement, implementation and maintenance. Preferably, the hot-wire anemometer is coupled advantageously to a control device of a conventional auxiliary heater for motor vehicles by providing the hot-wire anemometer with a hot wire, such as a PTC hot wire. In operation of the heater, a constant electrical voltage is applied to the PTC hot wire and is cooled by the hot air mass flow so that its temperature, and thus, its resistance change. In this way, the intensity of a current flowing through the hot wire is a measure of the heat exchange medium mass flow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a longitudinal cross section of an air heater in accordance with the invention; and
FIG. 2 shows a schematic of a hot-wire anemometer used in accordance with the air heater of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
The heater 1 shown in FIG. 1 is made as an air heater for a motor vehicle. The heat exchange medium is air which is generally received from the environment of the motor vehicle, and, after heating, is delivered to the passenger compartment of the motor vehicle. A tubular housing 2 on the left end face of the heater 1 has a hot air inlet opening 3 , and, on the opposite right end face, a hot air exit opening 4 . The housing 2 forms a hot air channel 5 , in the middle area of which there are the important components of the heater 1 for delivering and heating the hot air following one another on the longitudinal axis 6 .
Near the hot air inlet opening 3 is a hot air fan 7 which serves as a means for conveying a heat exchange medium such as hot air, and which is driven by an electric motor 8 which is located nearby. The electric motor 8 also drives a combustion air fan 9 which is located next to it, roughly in the center of the heater 1 . The combustion air fan 9 intakes combustion air and delivers the air to the burner 11 by way of a combustion air line 10 which penetrates the housing 2 . The burner 11 is also supplied with liquid fuel by a fuel line 12 , the liquid fuel serving to vaporize in the burner 11 and mix with the combustion air. The mixture burns in a combustion chamber 13 which is surrounded by the heat exchanger 14 . The resulting exhaust gas travels through the exhaust line 15 out of the housing 2 . When burned, the mixture releases heat energy to a wall 16 of the heat exchanger 14 which separates the combustion chamber 13 from the aforementioned hot air channel 5 . The hot air which is delivered by the hot air channel 5 for its part is heated by the wall 16 .
In the heater 1 , in the area of the electric motor 8 , a control device 17 is furthermore mounted which actuates, via lines (not shown), in particular, the electric motor 8 and a fuel metering pump 18 which is located outside the housing 2 . In conventional heaters, a temperature sensor is mounted on the wall 16 which serves as a means for protecting against the overheating of the heat exchanger 14 . One such conventional temperature sensor 19 a is shown by broken lines in FIG. 1 . The heater 1 which is shown on the other hand for protection against overheating has a hot-wire anemometer 19 which is located in the hot air channel 5 radially between the electric motor 8 and the housing 2 . The core of the hot-wire anemometer 19 is a hot wire 20 which extends, freely accessible to the hot air mass flow, pointed tangentially to the longitudinal axis in the hot air channel 5 . The two ends of the hot wire 20 are each attached to a holder 21 which is mounted outside on the control device 17 . Alternatively, the holder 21 can be made in one piece with the housing of the control device 17 . Each end of the hot wire 20 is connected by a line (not shown) to a control circuit (not shown) in the control device 17 .
By mounting the hot-wire anemometer 19 directly on the control device 17 , incorrect installation is precluded and electrical cable need not be laid. The hot-wire anemometer 19 can, alternatively, be mounted in the hot air channel 5 away from the control device 17 . Then attachment to the side of the electric motor 8 , where there is enough installation space available, diametrically opposite the control device 17 is advantageous. In this case, the hot-wire anemometer 19 in the flow direction of the hot air is also located directly behind the hot air fan 7 where fluctuations in the delivery amount of the hot air fan 7 can be detected with special precision and the hot-wire anemometer 19 is located in the area of the heater 1 which is “cooled” by the delivered hot air so that the heater is not exposed to a thermal load and the mass flow measurement is not adulterated by thermal effects.
In operation of the heater 1 , the hot-wire anemometer 19 determines the hot air mass flow delivered by the hot air fan 7 . The value of the current mass flow is compared in the control device 17 to a tolerance range for the theoretical mass flow and the burner 11 is adjusted if necessary. In normal operation of the heater 1 , the value of the delivered mass flow is within a predetermined tolerance range, depending upon the load state. If at this point, the hot air outlet opening 4 is dammed, because a passenger closes the heating in the passenger compartment of the motor vehicle, the delivered hot air mass flow is reduced abruptly. This reduction of the mass flow is immediately detected by the hot-wire anemometer 19 without thermally induced delays or deviations in the measurement occurring. The control device 17 can therefore turn down the burner 11 very quickly.
FIG. 2 illustrates the function of the hot-wire anemometer 19 in interplay with the control device 17 . The hot wire 20 of the hot-wire anemometer 19 with one end connected to the control device by one line at a time is made of a PTC material with a resistance which is dependent on the temperature of the material. In the operation of the heater 1 , on the two ends of the hot wire 20 a constant voltage U is applied so that electrical current with intensity I 1 flows. The hot wire 20 is heated by the current flow and a certain resistance R 1 is established. If at this point, the hot air fan 7 produces a hot air mass flow, this mass flow cools the hot wire 20 . The resistance of the hot wire 20 would, thus, drop to R 2 <R 1 . This tendency is, however, counteracted by a current with a greater intensity I 2 flowing. The magnitude of this current intensity I 2 is thus a measure of the hot air mass flow. If at this point, the aforementioned case arises that the hot air exit opening 4 is dammed, the hot air mass flow on the hot-wire anemometer 19 is slowed down or stopped. The hot wire 20 is, therefore, less cooled or not cooled at all, assumes a higher temperature, and its resistance rises. Thus, in turn the intensity 13 of the current through the hot wire 20 decreases; this is detected by the control device 17 and is compared to the corresponding limits of the tolerance range which is assigned to the instantaneous load range of the heater 1 . If a deviation is determined which indicates the danger of overheating of the heat exchanger, the control device 17 turns down the burner 11 accordingly. | A heating apparatus for a motor vehicle including a heat exchanger having a wall for separating a heated exhaust gas from a heat exchange medium, a conveyor mechanism for conveying the heat exchange medium along the wall, and a protective mechanism for protecting the heater against overheating. The protective mechanism determines the mass flow of the heat exchange medium delivered by the conveyor mechanism when the heater is actuated so that the danger of overheating the heater is reliably detected when the delivery of the heat exchange medium is dammed. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a wall system frame assembly comprising substantially two types of metal sections, by means of which the walls of a building can be erected in a simple manner.
It is conventional to erect building walls of frame structures consisting of metal sections, which have been coupled together. However, in the past, it has not been possible to form a wall system without using a great number of different sections and utilizing special tools and machines. This in its turn, significantly increased the difficulty in transporting materials, as well as requiring relatively large staff of specially trained personnel. Consequently, the overall costs of forming the wall system tended to be exceedingly high.
The present, by comparison, renders it possible in a simple and work-saving manner to erect building wall systems which comprise a relatively few standardized elements.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is described in greater detail in the following, by way of the preferred embodiment and with reference to the accompanying drawing, in which:
FIG. 1 shows a schematic, lateral view of a wall system formed in accordance with the present invention,
FIG. 2 shows a section through the wall system of FIG. 1, taken along the line II--II; in
FIG. 3 shows a section through the wall system taken along the line III--III in FIG. 1; and
FIG. 4 shows an alternative embodiment of the main section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A wall system frame assembly according to the present invention includes a first type of section, generally designated support section 1, and a second type of section generally designated connecting section 2. These sections can be complemented by third and fourth types of sections 3 and 4 respectively. The various types of sections comprising the preferred embodiment are each made of aluminium according a some conventional method.
The support section 1 has a substantially H-shaped configuration formed by two pairs of oppositely directed leg members which are provided with confronting leg surfaces having inwardly directed projections 5 formed on the ends thereof. Each support section 1 is further provided with at least one pair of parallel extending flange members on one outside portion and symmetrically positioned on either side of the section center of support section 1, which flanges support projections 6 directed inwardly toward each other. A web portion 7 of support section 1 is located about 10 mm from the section centre, and a pair of guide edges 8 are arranged about 10 mm on the opposite side of the section centre within the section.
Connecting section 2 has a substantially H-shaped configuration including two pairs of oppositely directed leg members of which opposed, outer leg surfaces formed with are provided with outwardly directed projections 9 in the form of hooks, which are countersunk slightly in relation to the lateral surfaces of connecting section 2. Connecting section 2 further includes a tongue-like locking section 10, which is drawn integral with connecting section 2 and is inclined inwardly to the section centre from a leg end on each side of the web portion 11 (FIG. 3). Owing to the design of the legs, an outer and an inner stop member 12 and 13, respectively, are formed in the respective leg end of section 2.
For a better understanding, the present invention is described in the following as the wall system can be imagined as being erected.
Support sections 1 are cut to predetermined lengths, and are mounted in pairs on parallel to the side of each other. Specific lengths 2 of the second type of connecting section 2 are positioned in suitably-spaced relationship and are attached by snapping between the support sections 1. In the preferred embodiment, the connecting sections 2' have a length of substantially 50 mm. Due to the fact that the projection 6 upon said snap-attachment of the connecting section 2' is located between the hook 9 and the outer stop member 12, the support section 1 is fixed relative to the connecting section 2'. In order to prevent unintentional inward bending of the legs of connecting section 2' after the mounting, and in order to frictionally lock connecting section 2' to support section 1, the tongue-like locking sections 10 are bent upward against the stop member 13 (FIG. 2). For the wall system now being erected, one support section 1 forms the outside of the wall and one further support section 1 forms the inside of the wall.
In order to support and attach the bottom support section or sill 1' (FIG. 1) to the wall system, preferably parts of a third type of section 3, which is generally designated as the attachment section, and which is fixed to the support section and ground 14 at equally spaced, intervals forming a row well leveled in height. This is carried out preferably so, that the fixing portion of the attachment section consists of a threaded metal rod 15, which is cast in the support (ground) and onto which a nut 16 has been screwed to desired levelled height on which rod is the section 3 rests. The shape of the section 3 is shown in FIG. 2 as including a substantially straight middle portion and a pair of L-shaped end portions attached to either end of the middle portion to provide good guidance in the lateral direction of the sill 1'. The sill further can be locked to the attachment section 3 by means of a plate 17 and nut 18, as shown in FIG. 2.
The mounting of upright support sections 1", which are comprised in the wall system and, like the sills 1' are formed of double support sections 1, is carried out in such a manner, that lengths 2" of the connecting section 2 are snappingly attached to the leg ends of the support section 1. Said lengths 2" of the connecting section 2 have in the preferred embodiment shown a length of substantially 20 mm and are attached by snapping in the places to be of the upright support sections 1". The uprights now are moved down over the connecting sections 2", so that these connecting sections are located in the space 19 of the particular support section 1 in question. The space 19, thus, is the one formed between the web portion 7 of the support section 1 and the pair of guide edges 8. The respective tongue-like locking section 10, which is easily accessible between the legs of the support section 1, is bent as stated previously for locking the lengths of connecting sections 22 to the sills 1'. The support section 1 and the lengths 2" of connecting section 2 also can be attached to each other by rivets.
The wall sheets 20 constituting the wall surfaces have such a width, that their edges extend in between the leg members of each of the opposed support sections 1 comprised in two uprights 1" positioned to the side of each other. The sheets 20 are mounted in the wall system by simply being moved down from above between the uprights and the support section leg members thereof before support sections 1 generally indicated by the horizontal girders 1'" of the same type as the sills and uprights are mounted. The sheets 20 are locked in a suitable manner to the sections, and the space between the sheets is filled with some type of insulation (not shown).
A horizontal girder 1'" or a horizontally attached window part 1 IV are mounted as follows.
The horizontal girder 1'" or the horizontal window part 1 IV consist, as mentioned before, of the parallel extending support sections 1, which are coupled together by means of specific lengths of the connecting section 2 having a length of substantially 50 mm. The girder or part is cut to a length corresponding to the distance between adjacently positioned upright support sections 1". At the ends of the support sections forming the girder 1'", the 20 mm long lengths 2" of the connecting sections 2 are inserted into the respective space 19, and the girder 1' is attached between the uprights 1". The lengths 2" of the connecting section 2 now are knocked or pressed against the uprights 1", so that the leg members of the connecting sections 2" snappingly engage with the inwardly directed projections 6 of the respective main section 1. After the girder has been finely adjusted, the locking sections 10 are knocked into locking position. The locking can be completed by riveting or screwing.
A window glass 21 (FIGS. 1 and 3) to be mounted between, for example, the window part 1 IV and the girder 1'", is mounted as follows. The window glass 21, which is slightly wider but slightly smaller in height than the opening formed between the uprights 1" and the girder and, respectively, window part, is moved with one edge in between the legs in the intended support section for one upright 1", brought with the opposite edge into flushing alignment with the corresponding intermediate space between the leg members of the opposite upright 1", and is moved back some distance so that the two vertical edges of the window glass now are between the leg members of the respective support section. The window glass is thereafter lifted so that its upper edge is located between the section legs concerned in the girder 1'". A receiving section 4 with a length corresponding to that of the window part 1 IV thereafter is laid on said part, and the window glass is lowered to rest on blocks 22 laid into the receiving section 4. The section 4 has such a height that with the glass resting on the blocks 22 the upper edge of the glass still is between the legs of the girder 1'". Suitable rubber strips 23 complete the mounting of the window glass 21. As appears from FIG. 3, the receiving section 4 has a substantially U-shaped configuration, the ends of the legs of which are designed in the same manner as the leg ends of the support section 1, so that a uniform type of mounting for the rubber strips 22 is obtained. The receiving section 4 further is provided with a pair of parallel extending guide flanges 24, which together with the projections 5 guide the receiving section 4 so as to prevent its lateral displacement relative to the support section 1.
It should have become apparent from the above description of the wall system according to the invention, that the system is of unique simplicity due to its extremely few parts, rendering the invention subject matter clearly superior to the known art.
The support section 1 also can be given the configuration as shown in FIG. 4, at which the guide edges 8 are replaced by an additional web portion 8'. On one side of the section, between the web portion 7 and the web portion 8', a part has been cut off, forming an opening through the respective leg members to permit access to the space 19 and to form projections 6.
The projections 5, which at this alternative have a simpler shape, and the projections 6 upon onhooking of the section 2 will be located between the hooks 9 and stop members 12 of said section. | An interlocking frame assembly for constructing and supporting a wall system, wherein a plurality of substantially H-shaped support sections are each formed with a pair of flange members extending substantially perpendicularly from a side thereof, with each pair of flange members having a pair of inwardly directed projections and each pair of leg members forming the H-shaped support section also having a pair of inwardly directed projections. A plurality of connecting sections are selectively positionable to engage the inwardly projecting projections of separate support sections to interconnect said support sections in perpendicular or parallel arrangement relative to one another. | 4 |
BACKGROUND OF THE INVENTION
This invention relates generally to integrated circuits and more specifically to an integrated circuit architecture which allows complex integrated circuits to be easily designed.
Integrated circuit technology has advanced in the number of transistors on a chip from fewer than one hundred to many millions. As a result, it is possible to make integrated circuits (ICs or chips) which perform increasingly complex functions and thus to replace a large number of discrete components with one or several ICs, with commensurate benefits in the size, cost, and reliability of electronic systems constructed using ICs. The sizes of electronic systems incorporating these ICs decrease drastically. Since the costs of these ICs are much less than the costs of the replaced discrete components, the costs of manufacturing these electronic systems also decrease. Since the reliability of electronic systems increases as the number of interconnections decrease, the reliability of electronic systems with these ICs increases due to the reduction in the number of discrete components to be connected.
As a result of the above described advantages, many IC manufactures devote a substantial amount of research and development resources to increase the number of transistors that can be deposited on a single chip IC so that more complex circuits can be implemented by the chip. However, the complexity of the circuits and the large number of available transistors make designing ICs more difficult. Consequently, computer-aided IC design tools have been developed to make it easier for the IC designer to synthesize the desired logic and functionality without the need to manipulate transistors or gates.
Two approaches have been developed to help the IC designers: "standard cell" and "gate array." In the standard cell approach, commonly used functional blocks are carefully designed and stored in a cell library. Designers can retrieve and interconnect appropriate blocks to provide desired functions. Typically, these blocks are simple structures which can be interfaced by simply routing interconnect wiring to the appropriate input/output terminals of the blocks.
Gate array technology involves the fabrication of a large number of base wafers containing identical integrated circuit elements (gates) up to but not including the first level of conductive interconnect. The IC designers "customize" the gate array by specifying only the conductive patterns used to interconnect the pre-fabricated gates.
One of the problems of both of these approaches is that it is difficult to use them to design ICs which perform complicated functions. This is because the standard cells and gate arrays are basic building blocks for all types of applications. Consequently, it takes a lot of skill, time and effort to integrate these basic building blocks into useful circuits which perform complicated functions.
As an example, circuits used for communication applications typically perform complex signal processing operations. Such circuits include finite impulse response filters, infinite impulse response filters, PSK demodulators, and correlators. These circuits incorporate complicated mathematical algorithms which could be understood and implemented in silicon only by extremely skilled engineers. Consequently, it is very difficult to design these circuits using the basic building blocks which are available in standard cell library and gate arrays.
Some electronic system manufacturers adopt a completely different strategy to solve the above described problem. Instead of relying on custom designed ICs, they use general purpose processor ICs, such as microcontrollers and digital signal processors. Software is used to customize the function of these ICs.
One of the problems of using these general purpose ICs is that they are typically slower than ICs designed to handle a specific application. In many applications where processing speed is a critical factor, such as high speed communication systems, the performance of general purpose ICs is not acceptable. Further, the use of software does not avoid the requirement that highly skilled engineers are needed to implement the complicated mathematical algorithms.
SUMMARY OF THE INVENTION
Broadly stated, the present invention is a single chip semiconductor device containing a bus for connecting between and among a plurality of "application syntax." The device can process digital and/or analog signals. Further, the device can perform signal and/or data processing functions. The application syntax are selected from a library of application syntax. These selected application syntax communicate via the bus and cooperatively perform a user specified function. The bus can carry commands, data and/or timing signals. Each selected application syntax includes a functional block which performs a predetermined function and an interface block which interfaces the functional block to the bus.
In the architecture of the present invention, an application syntax is preferably designed in a manner which captures a highly complex, but frequently used, type of data transformation into a single functional block. These application syntax can be considered primitive building blocks of an integrated circuit. They are a priori designed, implemented, and optimized for a target technology (for example, a specific microelectronics integration technology, such as CMOS). The collection of application syntax pertaining to a specific application are grouped in a catalog which is distributed to potential users. When it is time to design an integrated circuit that performs a particular user specified function, the appropriate application syntax are selected from the catalog.
The library of application syntax (which is comprised of one or several application specific catalogs) can be used to design a large variety of products. For example, if the catalog contains communication system related application syntax, it can be used to design products for cellular telephones, wireless local area networks, personal communication networks, and digital cable networks. As a result, the costs of designing the application syntax can be spread among many users of the catalog.
From the IC designer's perspective, each application syntax could be considered a "black box," with well defined input and output characteristics. Thus, there is no need for users of the catalog to have an in-depth understanding of how to implement these complex application syntax. The users only need to work with the system level functional building blocks. It is much easier and faster to design systems using these application syntax than to implement the same functionality by selecting, arranging and connecting standard cells or interconnecting thousands of gates. As a result, the costs and time-to-market of a product are significantly reduced.
A common problem encountered by product developers is how to reduce the costs of product enhancement and evolution. If a product is designed using the application syntax of the present invention, it is quite easy to change or add features to the product by removing and inserting application syntax. There is no need to re-design an entire system. Thus, the costs of product enhancement and evolution are reduced.
The interconnection between the application syntax of the present invention allows for loose coupling using a single bus such that a set of application syntax can operate asynchronously. Each application syntax on the bus can be invoked simultaneously (parallel processing) or staggered in time (pipeline processing). In addition, the application syntax can be enabled only at a time when its functionality is needed. Because the power usage of an application syntax depends on whether it is enabled, this feature allows for efficient power management.
The bus is used to carry both commands and data. The commands and data can be paired such that they are transmitted simultaneously by a single access to the bus. The number of words in the bus allocated to the commands and data can vary in each access. This "moving boundary" feature allows maximization of the efficiency of the bus.
The architecture of the present invention allows for distributed control. Each application syntax is capable of generating and sending commands and data to other application syntax. Thus, no central controller is required. This distributed control approach allows efficient implementation of highly time ordered, multi-mode application specific processing. However, the architecture of the present invention also allows an application syntax to control the operation of other application syntax in the integrated circuit. When one application syntax becomes a central controller for a group of other application syntax, the controlled application syntax are designated as an application syntax cluster.
The application syntax and interface architecture of the present invention allow application syntax with wide interface bandwidth needs to be interconnected as a group with a single physical interface which is separate from the above described bus. This application syntax `clustering` allows the interconnect interface bandwidth to be tailored for matching the bandwidth of data flow within the integrated circuit. This feature avoids data flow congestion.
The versatility of the ASP architecture is enhanced by its programmability feature. The adaptability of the application syntax and interface architecture of the present invention to different control mechanisms (distributed, centralized, or hybrid control) and to different interface bandwidth needs is an aspect of the ASP programmability. With the ASP programmability feature, the routing between application syntax, the configuration of application syntax, and the application syntax invocation times are programmable. Application syntax parameters can be set to a fixed value or controlled by a program. The program can be stored in an ASP memory or downloaded from an external entity.
One of the applications of the application syntax is in the area of digital communication. The application syntax contain complicated algorithms, such as digital filtering, correlating, and error correction. In the architecture of the present invention, a communication system designer does not have to understand the details of these algorithms. Complicated communication products, such as a spread spectrum, frequency hopping, time division multiple access modems, can be designed by merely selecting and combining the appropriate application syntax to provide the desired functionality.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the application specific processor (ASP) architecture of the present invention.
FIG. 2 is a block diagram of an interface access logic block in an application syntax of the present invention.
FIG. 3 is a block diagram showing a clock enable logic block in an application syntax of the present invention.
FIG. 4 is a block diagram showing an application syntax logic block in an application syntax of the present invention.
FIG. 5 is a block diagram of a modem implemented using the communication application specific architecture of the present invention.
FIG. 6 is a data flow diagram of the modem of FIG. 5.
FIG. 7 is a timing diagram showing the pipeline processing feature implemented in the modem of FIG. 5.
Other aspects and advantages of the present invention will become apparent from the following description of the invention, taken in conjunction with the accompanying drawings and tables, which disclose, by way of example, the principle of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention involves a processor architecture in which a plurality of functional elements, each designed to performed a specific function, are connected together to cooperatively perform a task. The architectural context in which these functional elements are integrated and the aggregation of the functional elements in order to perform the application dependent processing are referred herein as an application specific processor (ASP). Individual functional elements are called application syntax. An application syntax is typically highly complex, yet frequently used, type of data transformation. These application syntax could implement a digital or a combination of digital and analog functions.
FIG.1 is a schematic diagram of the ASP architecture 100 of the present invention. It shows a Command/Data/Timing bus 110 and a plurality of application syntax, such as application syntax 111, 112, and 113. These application syntax could be different, or some of them could be the same. Communication between the application syntax are carried out through the Command/Data/Timing bus 110.
Each application syntax contains essentially the same circuits for interfacing with the Command/Data/Timing bus 110. Thus, it is sufficient to describe in detail the interface circuits of only one of the application syntax, such as application syntax 111. Application syntax 111 contains a clock enable logic block 121, an interface access logic block 123, and an application syntax logic block 125. The application syntax logic block 125 performs a predefined function. For example, FIG. 1 indicates that the application syntax logic block 125 operates on user data that is supplied to the application syntax 111 through a bi-directional path designated the external interface 131 line. The clock enable logic block 121 and interface access logic block 123 interface the application syntax logic block 125 to the Command/Data/Timing bus 110. The clock enable logic block 121 provides the application syntax logic block 125 with timing signals and enables the application syntax logic block 125 only at the time when its function is needed. The interface access logic block 123 allows application syntax logic block 125 to receive commands and data from, and send commands and data to, other application syntax via the Command/Data/Timing bus 110.
In the ASP architecture 100, the structures of the clock enable block 121 and interface access logic block 123 in each application syntax are substantially the same, although some unique components, such as the application syntax's address, are different. Some of the components in the application syntax block 125 are also common to all the application syntax (e.g., components interfacing with the clock enable block 121 and interface access logic block 123). However, circuits in the application syntax which perform specific data and signal processing functions may be different (e.g., one application syntax functions as a demodulator, another functions as a CRC checker, etc.). Briefly stated, the application syntax may perform different functions, but the portions of the application syntax for interfacing to the Command/Data/Timing bus 110 are substantially the same. As a result, the application syntax can interface to one another using the Command/Data/Timing bus 110.
FIG. 2 shows a detailed block diagram of the interface access logic block 123, shown in FIG. 1. Like numerals in FIG. 1 and 2 denote like elements. The interface access logic block 123 contains an address decoder 140 connected to a command/data in block 142 and the clock enable logic block 121. The address decoder 140 receives address signals from the command/data bus 150 and causes the command/data in block 142 and the clock enable logic block 121 to accept commands and data which are intended for application syntax 111. The command/data bus 150 is a part of the Command/Data/Timing bus 110, shown in FIG. 1. The command and data processed by the command/data in block 142 is sent to the application syntax block 125. The interface access logic block 123 also contains a command/data out block 144 and an address out block 148. These two blocks transmit the command, data, and address information generated by the application syntax logic block 125 to the command/data bus 150. The interface access logic block 123 also contains a bus access circuit 146 which is connected to the command/data out block 144 and address out block 148.
The two command/data blocks 142 and 144 operate on an input/output format which consists of a pair of commands and data, each of varying size. The aggregate size of the commands and data are based on the operational needs of the specific application syntax logic. The described command and data pairing has moving boundaries which allows maximization of the physical interface (i.e., Command/Data/Timing bus 110) efficiency.
Because the structure of the interface access logic block 123 is substantially the same for all the application syntax, it is possible for one application syntax to send commands and data to another application syntax through the Command/Data/Timing bus 110. This "data driven" distributed control approach allows efficient implementation of highly time ordered, multi-mode application specific processing. Thus, in this architecture, there is no need for the control approach to be restricted to a fully centrally controlled approach; rather a distributed control, centralized control or a hybrid control approach can be used to best match the needs of the intended application. The ability of an application syntax to generate commands to other application syntax allows one application syntax to become a central controller for a group of other application syntax, which are designated as an application syntax cluster.
Another advantage of this architecture is that the Command/Data/Timing bus 110 is hidden from the application syntax logic (i.e., the application syntax logic need not know the details of the bus operation) Thus, the designer of the specific function for an application syntax does not have to know the bus operation and as a result, there is a gain in economy.
FIG. 3 shows a detailed block diagram of the clock enable logic block 121, shown in FIG. 1. Like numerals in FIGS. 1, 2 and 3 denote like elements. The clock enable logic block 121 contains a command status register 211 which accepts input from the timing bus 153, the command/data bus 150, and the address decoder 140 of the interface access logic block 123. The timing bus 153 is a part of the Command/Data/Timing bus 110 and typically contains a plurality of clock signals carried on different lines.
The command status register 211 receives time-related commands and data which are addressed to application syntax 111. The command status register 211 uses these commands and data to determine a mux select value and a epoch modulo value. The mux select value is sent to the multiplexer 213 through a set of mux select lines 214 so that the multiplexer 213 can select the desired clock (or epoch) from the timing bus 153. The epoch modulo value is sent to a command logic block 217 and defines the modulo therein (i.e. number of epochs to count before enabling a gated-clock), as explained below.
The output of the multiplexer 213 is connected to an activity timer 215. The activity timer 215 also receives a "count" signal from the command logic block 217 through a line 227. This count signal corresponds to the epoch modulo value, described above, in the command logic block 217. The activity timer 215 uses this count signal to count the epochs (selected by the command status regisgter) and sends a "complete" signal through a line 225 to the command logic block 217. The command logic block 217 then enables a gated-clock and generates a start signal (synchronous to the gated-clock). The start signal and gated-clock are coupled to the application syntax logic block 125 via lines 219 and 221, respectively. The command logic block 217 receives a "done" signal from the application syntax block 125 via a line 220. The command logic block 217 also contains circuits which allow it to enable and disable the gated-clock via commands from the command status register 211.
The clock enable logic block 121 causes the application syntax logic block 125 to be activated at specific occurrences of the specified timing epoch. For example, the clock enable logic block 121 can be configured to activate the application syntax logic block 125 at predefined epochs and disable the gated-clock during idle times, thereby limiting power dissipation of the application syntax 111. Furthermore, the clock enable logic block 121 allows the autonomous operation of the application syntax based on timing epochs distributed throughout the system. Thus, by allowing each application syntax to be enabled only at the time when its function is needed to be invoked, both the time ordering of data processing and efficient power management become inherent aspects of the architecture.
FIG. 4 shows a detailed block diagram of the application syntax logic block 125, shown in FIG. 1. Like numerals in FIGS. 1, 2, 3 and 4 denote like elements. The application syntax logic block 125 contains an application function logic block 256 which performs predefined functions unique to an application syntax, such as transformation of the user data supplied via the external interface 131 line. That is, application function block 256 contains circuits which are not part of the interface structure common to all application syntax. Application syntax logic block 125 also contains a command/data mux/demux block 252 which receives commands and data from the interface access logic block 123 and the gated-clock signal from the clock enable logic block 121. The command/data mux/demux logic block 252 extracts commands (for delivery to a command/decode logic block 254) and data (for bi-directional communication to an application function logic block 256) received from the interface access logic block 123.
The command/decode logic block 254 can be considered the controller of the application logic block 125. It controls the operation of the application syntax function logic block 256 via a line 262. That is, command/decode logic block 254 accepts commands from the interface access logic block 123 via the command/data mux/demux block 252, interprets those commands, and controls the operation of the application function logic block 256. An example of the operations are (i) configuring the application function logic block 256, and (ii) invoking a particular predefined transformation of the user data supplied by the external interface 131 line. Upon completion of a command, the application function logic block 256 sends a "complete" signal to the command/decode logic block 254 via a line 264.
As explained above, the start signal on 219 received by the command/decode logic block 254 is used to synchronize the invocation of the application function logic block 256. The command/decode logic block 254 also generates a "done" signal and transmits it (via line 220) to the clock enable logic block 121, which in turn disables the gated-clock to the command/decode logic block 254, the application function logic block 256, and the command/data mux/demux block 252. Disabling the gated-clock to these blocks essentially turns them off. Conversely, enabling the gated-clock turns them on.
As pointed out above, the application function logic block 256 in the application syntax is specifically designed to perform a predefined function. Each application syntax defines an application specific function which is a priori designed, implemented, and optimized for a target technology (for example, a specific microelectronics integration technology). A set of application syntax which perform different data and signal transformation functions can be put into a catalog. When it is time to design a system for a certain application (e.g., a modem for wireless communication), appropriate application syntax are selected from the catalog and placed on a Command/Data/Timing bus so that they can perform the desired function.
The catalog can be considered a collection of instructions in a programming language. A user can select the appropriate subset of instructions from the catalog to implement a programmable ASP which is matched to the intended application. The instruction set can be tailored to match the specific processing needs of a target application (for example, digital communications). The ASP Architecture is an architecture in which instructions in the instruction set can be combined to work in a cooperative manner to perform a certain application. The individual members of this application specific instruction set is designed in a manner which captures a highly complex, yet frequently used, type of data transformation into a single "syntax" which can be addressed as a primitive instruction at the application level. This type of syntax is referred to as an "application syntax." Examples of the physical embodiment of these syntax are the application syntax 111, 112, and 113, discussed above in connection with FIGS. 1-4.
Within the ASP architecture, an application syntax is invoked with two sets of fundamental arguments, namely, command (C) and time (T). In terminology analogous to software programming, the structure of the syntax is "Syntax (C, T)." Each syntax, when invoked, transforms a designated input array, data structure, and/or commands into an output by applying an application specific transformation or mapping. The command (C) argument of a syntax allows specific control parameters embedded with the application syntax to be set at desired values and hence allows the transformation performed by an application syntax to be varied from one invocation to another without altering the type of functional transformation performed. For example, within a Communication Application Specific Processor (CASP), an application syntax can be defined to be a filter function with the command argument allowing the filter bandwidth to be varied. The time (T) argument of the syntax allows the application syntax to be invoked at specific time epochs, where the value of the argument (T) specifies the time at which the application syntax is to be invoked or the time interval between successive invocations.
In the embodiment presented in FIGS. 1-4, the command arguments are transmitted on command/data bus 150 and processed by the interface access logic block 123 and the clock enable logic block 121. The time arguments are transmitted on the timing bus 153 and processed mainly by the clock enable logic block 121.
The ASP architecture allows a set of application syntax to be invoked simultaneously (parallel processing), staggered in time (pipeline processing), or sequential in time (non-overlapping processing). This capability allows considerable flexibility in the system design choices. Invocations simultaneous in time (parallel processing) allow high processing throughput to be realized. Invocations staggered in time (pipeline processing) or sequential in time (non-overlapping processing) allow one application syntax to act as a preprocessor for another application syntax. The time (T) argument of each application syntax determines the alignment of invocation epochs to realize the most efficient processing relative to another application syntax.
Appropriate application syntax are selected from the library containing the complete set of available application syntax. The architectural design allows any set of application syntax to be interconnected in a fully connected topology, which permits data flow between any two application syntax. This interconnection is based on a loose coupling, whereby a set of application syntax can operate asynchronously.
The versatility of the ASP architecture is enhanced by its programmability feature. The adaptability of the application syntax and interface architecture of the present invention to different control mechanisms (distributed, centralized, or hybrid control) and to different interface bandwidth needs is an aspect of the ASP programmability. With the ASP programmability feature, the routing between application syntax, the configuration of application syntax, and the application syntax invocation times are programmable. Application syntax parameters can be set to a fixed value or controlled by a program. The program can be stored in an ASP memory or downloaded from an external entity (which could be another IC designed using the ASP architecture of the present invention).
The ASP architecture targets implementations incorporating microelectronic integrated circuit technologies as well as board level technologies. Further, it can be implemented in both hardware and/or software. Because the constituent processing and invocation mechanisms are matched to a specific application, the ASP architecture offers the maximum throughput which can be achieved by the target technology with sufficient programming flexibility to realize the low cost benefits achieved by aggregating the production volume of several product markets with common processing needs. For example, it is possible to build a library in which the digital communication signal processing needs for the combined markets of several products, including cellular telephones, wireless local area networks, personal communication networks, digital cable networks, etc., are accommodated. The architecture also enables leveraging the expertise of applications experts to realize lower product design cost and shorter time-to-market advantages and allows system level object oriented programmability, which obviates the need for in-depth understanding of the complex aspects of a specific application processing. The rapid development cycle of efficient application specific circuits with inherent power management capabilities and the programming flexibility for addressing product enhancement and evolution with vastly reduced development cost are major benefits of this architecture.
One application of the ASP architecture of the present invention is a communication application specific processor (CASP). Table 1 shows the names and description of some of the application syntax in a catalog which can be used to design various CASPs.
TABLE 1______________________________________Communication Application Syntax CatalogName Description______________________________________Interleaver Convolutional and block interleaving with selectable row and column sizes.Deinterleaver Convolutional and block deinterleaving with selectable row and column sizes.Encoder Convolutional encoding with selectable rate, constraint length, and taps.Decoder Convolutional decoding with selectable rate, constraint length, and taps.CRC Checker Cyclic Redundancy Code checker with select- able length and taps.Reed-Solomon Reed-Solomon decoding with selectable length.DecoderBCH Decoder BCH decoding with selectable length and syndrome calculation.FIR Filter FIR filter with selectable number of co- efficients and coefficient values.IRR Filter IRR filter with selectable coefficient values.PSK PSK demodulator with selectable type and rate.DemodulatorFSK FSK demodulator with selectable number ofDemodulator tones, tone frequencies, and rates.Correlator Correlator with selectable length and taps.State Machine Generic State Machine with selectable number of states, boundary conditions, and outputs. When used in conjunction with application specific microcode, it provides implemen- tation of a wide variety of application syntax.______________________________________
An exemplary communication system designed using the ASP architecture of the present invention is a modulator/demodulator (modem) implementing a spread spectrum, frequency hopping (SS/FH), time division multiple access (TDMA) signaling scheme. The SS/FH aspect is provided by randomization of the carrier frequency of each burst. The TDMA aspect is provided by dividing time on the channel into TDMA bursts, with the multiple access duty cycle defined as a frame. The time position of an assigned burst within a frame is randomized. The multiple access scheme assigns dynamically on demand a data stream to each burst to support the user data. Each burst is defined by a set of parameters shown in Table 2.
TABLE 2______________________________________SS/FH Burst Parameters of Modem 400______________________________________Carrier Carrier frequency derived using aFrequency specified pseudo random code (PN-Code) generator.Modulation Binary Phase Shift Keying (BPSK) ortype Quatemary Phase Shift Keying (QPSK).Matched Filter Coefficients for matched filter.ParametersData Rate Variable number of symbols per burst.Interleaver Variable number for length and width.ParametersCoding Type None or convolutional encoding/Viterbi decoding.Coding Rate = 1/2, 3/4, 7/8; Constraint Length =Parameters 7, 9.______________________________________
FIG. 5 depicts a top level block diagram of a SS/FH TDMA modem 400 implemented using the CASP. Specifically, the application syntax utilized in the example are shown in Table 3. These application syntax communicate through a command/data/timing bus 499, where each application syntax can be invoked (or activated) at different rates. Bus 499 is a realization of the Command/Data/Timing bus 110 of FIG. 1.
Each application syntax defined in modem 400 accepts an input configuration command which governs the data transformation and an input timing command which governs the invocation time. This command structure has been defined as Syntax (C,T) in the ASP architecture of FIG. 1. An application syntax, upon invocation, sets its parameters to the appropriate values, processes the input data, and gates its input clock off until the next invocation command occurs. Thus, power savings are inherently provided by gating the clock off. The application syntax defined in modem 400 have different application syntax logic (i.e., block 125 of FIG. 1) for performing different signal processing functions. However, all of these application syntax utilize the same interface structure to connect to the command/data/timing bus 499.
TABLE 3__________________________________________________________________________Application Syntax Used to Implement CASP Modem 400Name Description__________________________________________________________________________Downlink De- An autonomous application syntax which performs burst-by-Randomizer burst control of the demodulation cluster and generates downlink burst/frame clocks and downlink synthesizer frequency hopping commands. Implemented using the state machine syntax of Table 1.Uplink An autonomous application syntax which generatesRandomizer uplink burst/frame clocks and uplink synthesizer commands containing the uplink modulation and frequency hopping commands. Implemented using the state machine syntax of Table 1.Matched Part of demodulation cluster configured at the burst rate toFilter perform matched filtering of the received signal.PSK Part of demodulation cluster configured at the burst rate toDemodulator perform BPSK or QPSK demodulation of the filtered signal.Sync Part of the demodulation cluster configured at the burst rateCorrelator to calculate synchronization metrics for time and frequency tracking.Deinterleaver Autonomous application syntax configured dynamically to deinterleave data at the frame rate.Decoder Autonomous application syntax configured dynamically to decode data at the frame rate.CRC checker Autonomous application syntax configured dynamically to check the decoded data stream for errors.Encoder Autonomous application syntax configured dynamically to encode data at the frame rate.Interleaver Autonomous application syntax configured dynamically to interleave data at the frame rate.Shared Autonomous application syntax consisting of a block ofMemory memory with capability to interface with internal Command/Data/Timing Bus.Data/Control Autonomous application syntax designed to connect anInterface external bus to the internal Command/Data/Timing__________________________________________________________________________ Bus.
In modem 400 of FIG. 5, both the centralized as well as the distributed control aspects of the ASP architecture are used to support dynamic modem reconfiguration on a burst-by-burst basis and data processing on a frame-by-frame basis. The centralized control is provided by a downlink de-randomizer 404 and an uplink randomizer 406, which coordinate the downlink and uplink digital signal processing, respectively, on a burst-by-burst basis. The distributed control is provided by autonomous application syntax on a frame-by-frame basis for data processing. Specifically, these autonomous application syntax are the encoder 408, the interleaver 425, the CRC checker 424, the decoder 423, and the deinterleaver 409.
The modem 400 incorporates a shared memory syntax 416, which provides a loose coupling between all application syntax. This eliminates the hardware overhead of multiple separate data and address lines as well as separate memories. Each application syntax performs its particular task(s) on its input data and passes its output to the next application syntax via the shared memory syntax 416.
As illustrated in FIG. 6, data and control are transferred between application syntax via preassigned segments in shared memory syntax 416. Like elements in FIGS. 5 and 6 have like numerals. Associated with each preassigned memory segment (i.e., segments 460, 462, 464, and 472) is a `write` pointer (such as pointer 482), `read` pointer (such as pointer 483), `segment length` value (such as value 484), and the data to be processed (such as deinterleaved data 485). The `write` pointer is maintained by the application syntax writing the data, while the `read` pointer is maintained by the application syntax reading the data. Each application syntax examines the `write` and `read` pointers to determine if enough data is available to process and will shutdown until the next frame clock epoch when data is not available. In addition to providing inherent power saving, this feature allows data to be processed only when available and at the desired throughput.
The operation of the downlink processing performed by modem 400 is now described. The signaling structure on the downlink incorporates a time-division multiplexed, frequency hopped waveform with varying burst data rates multiplexing communication data, access control data, and synchronization information. The synchronization information is demodulated with the sync correlator 428 for acquiring and tracking the received signal. The communication data and the access control data are demodulated with the PSK demodulator 429. Both application syntax 428 and 429 output data into shared memory syntax 416 for further data processing by other autonomous application syntax.
In modem 400, matched filter 427, sync correlator 428 and PSK demodulator 429 are grouped into a demodulation cluster 430. It demodulates the received signal in real-time at the burst rate and places the demodulated data in shared memory syntax 416. Matched filter 427 matches the communication characteristic of the incoming digital signal, thereby providing filtered samples to sync correlator 428 and PSK demodulator 429. To accommodate the high bandwidth of the filtered signal, the components of demodulation cluster 430 are connected by a high bandwidth bus, called the filtered signal bus 431.
In modem 400, centralized control of the demodulation cluster 430 is performed by the downlink de-randomizer 404. Specifically, the downlink de-randomizer 404 performs the following functions:
(1) generates and synchronizes the PN-Code word,
(2) calculates the hopped carrier frequency,
(3) generates the corresponding frequency command and strobe for a downlink synthesizer external to modem 400,
(4) generates all the necessary clocks, including burst clock and frame clock, and
(5) configures the demodulation cluster 430 on a burst-by-burst basis.
Configuration of the demodulation cluster 430 consists of setting up the matched filter 427 to the burst data, and selecting either sync correlator 428 or PSK demodulator 429. Based on a generated PN-Code, the downlink de-randomizer 404 identifies the incoming burst index. Using this identified burst index, the downlink de-randomizer 404 accesses the shared memory syntax 416 to determine the burst configuration parameters contained in the downlink "command template". The command template is effectively the CASP instruction program written specifically for this modem application. The information in the command template (program) defines the modem operation and can be changed according to the changing downlink parameters. Information in the command template (program) defines the signal processing commands as well as data processing commands. The signal processing commands are used to configure the demodulation cluster 430, while the data processing commands are used to configure the autonomous data processing syntax.
The downlink de-randomizer 404 writes a timing command (T) to each of the components of the demodulation cluster 430, which configures the demodulation cluster 430 to be activated at the burst clock epoch. Prior to the burst clock epoch, the downlink de-randomizer 404 writes configuration commands (C) to each component of the demodulation cluster 430. The demodulation cluster 430 activates on the burst clock epoch and processes the data as defined in the configuration command supplied by the downlink de-randomizer 404. This is an example of dynamic reconfiguration at the burst clock epoch.
The demodulated data is further processed by autonomous application syntax. These application syntax are activated at the downlink frame clock epoch, process the data, and then shutdown until the next downlink frame clock epoch. This results in substantial power savings during operation. In modem 400, each autonomous application syntax maintains its input and output in shared memory syntax 416. FIG. 6 shows the data flow among the centralized controlled demodulation cluster 430 and the distributed controlled data processing syntax. Signals received by modem 400 on line 432 are demodulated by demodulation cluster 430. The demodulated data is placed in a demodulation data segment 460 of shared memory syntax 416 via command/data bus 498, which consists of a portion of command/data/timing bus 499. This demodulated data is subsequently processed by deinterleaver 409. The result is stored in a deinterleaver data segment 462 in shared memory syntax 416. The deinterleaved data is subsequently processed by decoder 423. The decoded data is stored in a decoded data segment 464 in shared memory syntax 416. The decoded data is then check for errors by CRC checker 424 and placed in a received user data segment 472. The received user data can then be extracted by an external entity via the data/control interface syntax 426 on the external bus 490.
The configuration commands of the autonomous application syntax are provided as part of the downlink command template (program) in shared memory syntax 416. As described previously, the instructions for each of these application syntax consist of two arguments; namely, the command argument (in this case, the configuration command) and the time argument (in this case, the invocation time). Upon invocation, the application syntax will decode the command argument (C) and configure its parameters accordingly. Each application syntax decodes the time argument (T) to determine the invocation epoch. The time argument can be implemented as a command to select either the burst clock 495 or the frame clock 496 of the timing bus 497, which is a part of command/data/timing bus 499, and use it to establish a periodic invocation epoch.
The pipelining capability of the ASP architecture is used in modem 400, where the time arguments of the CASP command template (program) were chosen to perform the above described operations in a processing pipeline. FIG. 7 shows a programmed downlink processing pipeline implemented in modem 400. The input signal on line 432 is demodulated in real time at the burst rate, while deinterleaving, decoding, and CRC checking are processed in subsequent frames at the frame rate.
The downlink processing pipeline implemented in modem 400 is detailed here. Through programming of the application syntax forming modem 400, the received signal 432 is processed in accordance with time on the channel divided into TDMA bursts, with the multiple access duty cycle defined as a frame. In FIG. 7, the progression of time is illustrated as a sequence of frames having sequentially increasing frame numbers. Specifically, the sequence shown in FIG. 7 is frame (N) 500, followed by frame (N+1) 501, followed by frame (N+2) 502, followed by frame (N+3) 503, where N is an arbitrary integer counting the number of flames. Within any given frame, the progression of time is illustrated as a sequence of bursts having sequentially increasing bursts numbers. Specifically, the sequence shown in FIG. 7 is burst (M) 570, followed by burst (M+1) 571, followed by burst (M+2) 572, where M is an arbitrary integer counting the number of bursts within a frame.
The downlink processing pipeline implemented in modem 400 starts with matched filter/demodulation (N) 510 performed on the received data of frame (N) 500. Specifically, the following programmed sequence of operations is performed:
(a) Matched filter (M) 580 is performed on burst (M) 570 of frame (N) 500.
(b) Demodulation (M) 590 is performed on the matched filter (M) 580 output data.
(c) Matched filter (M+1) 581 is performed on burst (M+1) 571 of frame (N) 500.
(d) Demodulation (M+1) 591 is performed on the matched filter (M+1) 581 output data.
(e) Matched filter (M+2) 582 is performed on burst (M+2) 572 of frame (N) 500.
(f) Demodulation (M+2) 592 is performed on the matched filter (M+2) 582 output data.
(g) Et cetera until all designated bursts within frame (N) 500 have been matched filtered and demodulated.
(h) In the following frame, deinterleave (N) 520 is performed on the demodulation (M) 590, demodulation (M+1) 591, demodulation (M+2) 592, etc., output data.
(i) In the following frame, decode (N) 530 is performed on the deinterleave (N) 520 output data.
(j) In the following frame, CRC check (N) 540 is performed on the decode (N) 530 output data.
(k) In the following frame, received data 550 is extracted from the CRC check (N) 540 output data and passed to an external entity.
Similarly, frame (N+1) is processed as follows:
(a) Matched filter (M) 580 is performed on burst (M) 570 of frame (N+1) 501.
(b) Demodulation (M) 590 is performed on the matched filter (M) 580 output data.
(c) Matched filter (M+1) 581 is performed on burst (M+1) 571 of frame (N+1) 501.
(d) Demodulation (M+1) 591 is performed on the matched filter (M+1) 581 output data.
(e) Matched filter (M+2) 582 is performed on burst (M+2) 572 of frame (N+1) 501.
(f) Demodulation (M+2) 592 is performed on the matched filter (M+2) 582 output data.
(g) Et cetera until all designated bursts within frame (N+1) 501 have been matched filtered and demodulated.
(h) In the following frame, deinterleave (N+1) 521 is performed on the demodulation (M) 590, demodulation (M+1) 591, demodulation (M+2) 592, etc., output data.
(i) In the following frame, decode (N+1) 531 is performed on the deinterleave (N+1) 521 output data.
(j) In the following frame, CRC check (N+1) 541 is performed on the decode (N+1) 531 output data.
(k) In the following frame, received data 550 is extracted from the CRC check (N+1) 541 output data and passed to an external entity.
The downlink processing pipeline continues indefinitely with the same pattern repeating until modem 400 is reconfigured into a different mode or turned off.
The programming capability of the CASP modem 400 allows any application syntax to be commanded by the time argument to select one of the clocks provided on the command/data/timing bus 499 and use the selected clock to generate invocation epochs by counting modulo (N) of the selected epoch or invoke when the selected clock reaches a specific value. For example, the CASP command template (program) defines the specified encoder invocation period to consist of multiple frames. In this example, the encoder input data will accumulate in its designated shared memory segment until processed by the encoder upon invocation.
Because it is obvious for persons skilled in the art to build the uplink portion of modem 400 once the downlink portion is understood, only the downlink portion needs to be described. Consequently, the structure and operation of the uplink portion is not described here.
What is described is the ASP architecture of the present invention. It should be obvious to one of ordinary skill in the art to apply the invention to various types of applications. While only several preferred embodiments of the invention have been presently described in detail herein, many alterations and modifications can be made without departing from the spirit and the scope of the invention. Accordingly, it is intended that the scope of the invention is only limited by the appended claims. | The architecture and design method of an application specific processor ("ASP") is disclosed. The ASP is designed by integrating selected pre-designed application elements contained in a library. These selected application elements can communicate with each other via a bus. Post-synthesis tailoring of the synthesized ASP is accomplished by using an instruction program which sequences the invocation of each application element and provides reconfiguration and data input/output routing commands thereto. A power management design is incorporated within the application elements allowing the majority of the application elements to be turned on only during periods of invocation. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a novel 4,8-dimethylbicyclo[3.3.1]nonane derivative, and more particularly, to a 4,8-dimethylbicyclo[3.3.1]nonane derivative having a unique and strong perfume and hence expected to be useful as perfumery.
The compound of the present invention is a novel bicyclic compound undisclosed in literatures and also a fragrant substance.
SUMMARY OF THE INVENTION
According to this invention, there is provided a novel 4,8-dimethylbicyclo[3.3.1]nonane derivative represented by the formula [I]: ##STR2## wherein one of X and Y represents a hydroxyl group, a straight or branched alkoxy group having 1 to 5 carbon atoms or an acyloxy group having 2 or 3 carbon atoms and the other represents a hydrogen atom, or 57 jointly represent an oxo group (═O ); and a dotted line represents optional presence of a double bond.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a gas chromatogram of the product of Example 1;
FIG. 2 shows an infrared absorption spectrum of the product of Example 1;
FIG. 3 shows a H 1 -nuclear magnetic resonance spectrum of the product of Example 1;
FIG. 4 shows a Newman's projection formula of the product of Example 1; and
FIG. 5 shows a gas chromatogram of the product of Example 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present compound can be prepared by subjecting 3-(4-methyl-3-cyclohexenyl)butyraldehyde (hereinafter referred to briefly as limonene aldehyde) [II] to intramolecular ring closure in the presence of an acid catalyst or further reducing the ring double bond thereof and furthermore by etherification, esterification or oxidation, as illustrated below. In particular, said intramolecular ring closure may proceed with an extremely high stereoselectivity. ##STR3##
In the above formulae, R 1 represents a straight or branched alkyl group having 1 to 5 carbon atoms and R 2 represents a methyl group or an ethyl group. As the straight or branched alkyl group of 1 to 5 carbon atoms and represented by R 1 , there may be mentioned a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a n-amyl group, an isoamyl group, a sec-amyl group, a tert-amyl group and the like.
The (+) and/or (-) limonene aldehyde represented by the above-mentioned formula [II], which may be employed as a starting material in this invention, can be prepared through hydroformylation reaction of limonene as disclosed in Japanese Provisional Patent Publication No. 47638/1980. More specifically, said aldehyde can be prepared by the reaction of (+) and/or (-)-limonene with carbon monoxide and hydrogen. 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol or its reduced product, 4,8-dimethylbicyclo[3.3.1]nona-2-ol, represented by the above formula [IA] or [IA'] can be prepared according to the process as depicted below. Namely, said alcohols can be prepared by subjecting (+) and/or (-)-limonene aldehyde [II]to intramolecular ring closure in the presence of an acid catalyst or by further reduction of the ring double bond. In particular, intramolecular ring closure may proceed with an extremely high stereoselectivity. More illustratively, the six types of the present compound as shown below can be prepared, for instance, from (+)-limonene. ##STR4##
The compounds [IA-a] and [IA-b] are stereoisomers of (1R, 2R,5R)-4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol, while the compounds [IA'-a], [IA'-b], [IA'-c] and [IA'-d] are stereoisomers of (1R,2R,5R)-4,8-dimethylbicyclo [3.3.1]nona-2-ol, respectively.
Similarly, two types of stereoisomers of (1S,2S,5S)-4,8-dimethylbicyclo[[3.3.1]nona-7-en-2-ol and four types of stereoisomers of (1S, 2S, 5S)-4,8-dimethylbicyclo[3.3.1]nona-2-ol, which are in an enantiomerism relationship with the above-mentioned compounds, may be prepared from (-)-limonene aldehyde.
As the acid catalyst which may be employed for intramolecular ring closure reaction of limonene aldehyde, there may be mentioned, for example, an inorganic acid such as sulfuric acid, phosphoric acid or boric acid, an organic acid such as p-toluenesulfonic acid or benzenesulfonic acid and a strongly acidic cation exchange resin. An amount of the acid catalyst employed may be varied over a wide range, but 0.5 to 30% by weight, preferably 3 to 15% by weight, thereof may be usually suitable based on the starting limonene aldehyde.
Said intramolecular ring closure reaction may proceed even in the absence of a solvent, but may proceed more smoothly in the presence of a solvent. As the solvent, there may be mentioned, for example, water, a lower carboxylic acid such as formic acid or acetic acid, a lower alcohol such as methanol or ethanol, an aliphatic or aromatic hydrocarbon such as hexane, benzene or toluene or a mixture thereof. A volume of the solvent employed is suitably 0.5 to 20 times, preferably 1 to 5 times, based on the limonene aldehyde. This reaction may smoothly proceed at a reaction temperature of 0° to 100° C., preferably 10° to 30° C.
The compound [IA'] can be prepared by a conventional catalytic hydrogenation reaction of the compound [IA]. As the catalyst which may be employed, there may be applied any catalysts commonly employed for catalystic hydrogenation such as palladium on carbon, Raney nickel or platinum oxide. An amount of the catalyst to be applied is 0.1 to 20% by weight, preferably 2 to 10% by weight, based on the 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol. This reaction may proceed even in the absence of a solvent, but it is usually and preferably carried out in the presence of a solvent. A lower alcohol such as methanol or ethanol, acetic acid, dioxane or cyclohexane may be preferably employed. A volume of the solvent to be employed is suitably 0.5 to 20 times, preferably 1 to 5 times, based on the 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol. This reaction may smoothly proceed at a reaction temperature of 0° to 150° C., preferably 50° to 100° C. and hydrogen pressure for reaction is 0.1 to 50 atm, preferably 1 to 30 atm.
As illustrative examples of the 4,8-dimethylbicyclo[3.3.1 ]nona-7-en-2-yl alkyl ether represented by the above formula [IB], there may be mentioned 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl methyl ether, 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl ethyl ether, 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl isopropyl ether, 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl isoamyl ether and the like. The compound [IB] may be prepared through intramolecular ring closure etherification reaction or etherification reaction of the limonene aldehyde [II] or 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol [IA] with an alcohol compound [III] of the formula:
R.sup.1 OH [III]
(wherein R 1 is the same as defined above) in the presence of an acid catalyst with removed of the water formed in situ. As the acid catalyst which may be employed for the above reaction, there may be mentioned, for example, an inorganic acid such as sulfuric acid, phosphoric acid or boric acid, an organic acid such as p-toluenesulfonic acid or benzenesulfonic acid and a strongly acidic cation exchange resin. An amount of the acid catalyst employed may be varied over a wide range, but 0.5 to 30% by weight, preferably 3 to 15% by weight, thereof may be usually suitable based on the starting limonene aldehyde [II] or the compound [IA]. An amount of the alcohol compound [III] employed is 2 to 20 times moles, preferably 5 to 15 times moles, based on the starting limonene aldehyde [II] or the compound [IA]. Reaction temperature is usually and preferably in the range of ordinary temperature to a reflux temperature of the alcohol compound [III].
As an alternative process, the compound [IB] may be also prepared by contacting the compound [IA] with an alkali metal or an alkali metal hydride in the presence of a suitable solvent to form the corresponding alkali metal salt and then reacting the salt as such, without isolation, with an alkyl halide. As the alkali metal or alkali metal hydride, there may be employed, for example, sodium, potassium, sodium hydride, lithium hydride and the like. An amount thereof to be used is 1 to 10 times moles, preferably 2 to 5 times moles, based on the compound [IA]. As the solvent, there may be mentioned, for example, benzene, toluene, tetrahydrofuran, dimethylformamide and the like. An amount thereof is 1 to 10 times, preferably 1 to 5 times in volume based on the compound [IA]. Reaction temperature is usually 0° to 100° C., preferably 20° to 80° C.
As illustrative examples of the 4,8-dimethylbicyclo[3.3.1]nona-2-yl alkyl ether having the above formula [IB'], there may be mentioned 4,8-dimethylbicyclo[3.3.1]nona-2-yl ethyl ether, 4,8-dimethylbicyclo[3.3.1]nona- 2-yl isopropyl ether and the like. The compound [IB'] can be prepared by a conventional catalytic hydrogenation reaction of the compound [IB], in the same manner as mentioned in the preparation of the compound [IA'].
The compound [IB'] may also be prepared by etherification of the compound [IA']. This reaction can be effected in the same manner as done in the above-mentioned preparation of the compound [IB] using the acid catalyst, or alkali metal or alkali metal hydride.
As illustrative examples of the 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl esters represented by the above formula [IC'], there may be mentioned 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl acetate, 4,8-dimethylbicyclo[3.3.1]nona- 7-en-2-yl propionate and the like.
Also, as illustrative examples of the 4,8-dimethylbicyclo[3.3.1]nona-2-yl esters represented by the above formula [IC'], there may be mentioned 4,8-dimethylbicyclo[3.3.1]nona-2-yl acetate and the like.
The compound [IC] or [IC'] may be prepared by esterifying the compound [IA] or [IA'] according to a conventional method, respectively. More specifically, the desired product can be easily produced by treating the compound [IA] or [IA'] with, for example, an acid halide such as acetyl chloride or propionyl chloride or an acid anhydride such as acetic anhydride or propionic anhydride. An amount of the acid halide or anhydride to be employed is 1 to 2 times moles, preferably 1 to 1.2 times moles, based on the compound [IA] or [IA']. This reaction can be advantageously carried out in the presence of an organic base such as pyridine, triethylamine and the like. An amount of these organic base to be used is 1 to 2 times moles, preferably 1 to 1.2 times moles, based on the acid halide or anhydride. The reaction may proceed even in the absence of a solvent, but it is usually preferred to use a suitable solvent such as benzene, toluene, tetrahydrofuran or dioxane. A volume of the solvent to be employed is 1 to 10 times, preferably 1 to 5 times based on the compound [IA] or [IA']. Reaction temperature is 0° to 100° C., preferably 20° to 80° C.
4,8-Dimethylbicyclo[3.3.1]nona-7-en-2-one represented by the formula [ID] and 4,8-dimethylbicyclo[3.3.1]nona-2-one represented by the formula [ID'] can be prepared by oxidation of the compound [IA] and [IA'] according to a conventional method, respectively. As the oxidizing agent which may be employed, there may be mentioned, for example, chromic acid, silver oxide, potassium permanganate or potassium dichromate. An amount of the oxidizing agent to be employed is 1 to 10 times moles, preferably 1 to 3 times moles, based on the compound [IA] or [IA']. A solvent may be preferably employed and, as preferred solvents, there may be mentioned, for example, water, acetone, hexane, benzene and the like. An amount of the solvent to be used is 1 to 20 times in volume, preferably 5 to 15 times, based on the compound [IA] or [IA']. Reaction temperature is -10° to 30° C., preferably -5° to 25° C.
This invention will be more fully explained by way of the following examples, but they are not contemplated to be limiting the scope of this invention.
EXAMPLE 1
A mixture of 80 g of (+)-limonene aldehyde [[α] D 25 = +98.3° (c=2.2, CHCl 3 )], 100 ml of water, 30 ml of acetic acid and 7 ml of conc. sulfuric acid was reacted under stirring for 12 hours at a reation temperature of 25°-30° C. After completion of the reaction, an organic layer was separated, neutralized and the water with saturated aqueous sodium hydrogen carbonate, washed with water and then dried over magnesium sulfate. Subsequently distillation under reduced pressure gave 67.9 g of (1R,2R,5R)-4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol, which had a camphor-like smell.
b.p.: 86°-90° C./0.6 mmHg (Yield: 84.9 %)
[α] D 25 =+157.4° (c=2.1, CHCl 3 )
In this compound, there are presumed four types of isomers with regard to steric configuration at the 2- and 4-positions thereof, but analysis of the following analytical results revealed that this compound is an approximately 1:1 equimolar mixture of the compound of the formula [IA-b] having the endo-methyl group at the 4-position thereof and the endo-hydroxyl group at the 2-position thereof and the compound of the formula [IA-a] having the exo-methyl group at the 4-position thereof and the same hydroxyl group.
(1) Gas chromathography (See FIG. 1)
Gas chromatography was effected by using 25 m of a fused silica capillary column coated with polyethylene glycol and having an inner diameter of 0.31 mm under conditions of a hydrogen flame detector of 2.0 cc/min. of a carrier gas flow rate, 150° C. of a column temperature. As a result, two peaks were detected with areas of 48.0 % and 49.9% at 7.84 minutes and 8.26 minutes, respectively.
(2) Gas chromatographic mass spectrometry analysis
Measurement was done under the same condition as in the above gas chromatography and mass spectra of the said two peaks showed molecular ion M + of 166 (C 11 H 18 O). Also, both mass spectral patterns are closely similar, which demonstrates that these compounds are stereoisomers which are difficult to distinguish by their respective mass spectra.
(3) Infrared absorption spectrum (See FIG. 2)
The following characteristic absorption bands were observed:
______________________________________3400 cm.sup.-1 (OH, streching vibration)3020 cm.sup.-1 ##STR5##1660 cm.sup.-1 (CC, streching vibration) 802 cm.sup.-1 (CH, CHC, out-of-plane vibration).______________________________________
Thus, presence of a hydroxyl group and a tri-substituted double bond was confirmed, but no carbonyl group observed.
(4) NMR spectrum
H 1 -NMR spectrum was measured in a deuterochloroform solution at a resonance frequency of 269.65 MHz, while C 13 -NMR spectrum at a resonance frequency of 67.80 MHz. Measurement of pseudo-contact shift in the C 13 -NMR using as a shift reagent tris(dipivalomethane)europium proved a relationship of steric configuration between respective atoms forming a molecule. Also, structure of each carbon atom type (primary, secondary, tertiary and quaternary carbons) was determined by using off-resonance. Because of co-existence of two types of isomers, two chemical shifts in each group except for the methyl group located at the 8-position thereof were observed and a total of 21 peaks was observed.
The H 1 -NMR (See FIG. 3) showed the following absorptions:
______________________________________δ ppm 5.54 olefinic hydrogenδ ppm 4.40 hydrogen adjacent to hydroxyl group (2-position)δ ppm 3.83 hydrogen adjacent to hydroxyl group (2-position)δ ppm 1.78 8-methylδ ppm 1.03 4-methylδ ppm 0.92 4-methyl______________________________________
Steric configuration of the 2-hydroxyl group has been proved to be "endo" from the splitting pattern of the absorption lines in the 2-hydrogen (H 2 ) was spin-bonded to Hax at 10.5 Hz and to Hex and H 1 at 3.9 Hz and thus is "endo" as shown in FIG. 4 according to Karplus' rule.
EXAMPLE 2
Into a 50 cc glass autoclave were charged 5.5 g of the (1R,2R,5R)-4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol obtained in the above Example 1, 1.0 g of 5% Pd/C and 25 ml of ethanol and the reaction was effected by heating under stirring at reaction hydrogen pressure of 3 to 5 atm and a temperature of 70° C. over 3 hours. After cooling, the content was removed from the autoclave, the catalyst was filtered off and the solvent was distilled off from the filtrate under reduced pressure to give 5.3 g of semi-crystalline (1R,2R,5R)-4,8-dimethylbicyclo[3.3.1]nona-2-ol, which had a menthol-like smell.
This compound was proved from the following analytical results to be a mixture of the 4-endo, 8-endo compound of the formula [IA'-a], the 4-endo, 8-exo compound of the formula [IA'-b], the 4-exo, 8-endo compound of the formula [IA'-c] and the 4-oxo, 8-exo compound of the formula [IA'-d].
The (1R,2R,5R)-4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol obtained in the above Example 1 is a 1:1 equimolar mixture of the two isomers and hence the compound obtained from hydrogenation of the former disappeared a double bond and the 8-carbon newly became an asymmetric carbon atom, whereby 4 types of isomers were formed.
(1) Gas chromatography (See FIG. 5)
Gas chromatogram was measured under the same conditions as in the above Example 1 to detect 4 peaks at 7.27 minutes, 7.53 minutes, 8.07 minutes and 8.46 minutes, respectively. Respective area were designated A, B, C and D, respectively, in the order of the corresponding component effusion.
This mixture is in a liquid state at ordinary temperature, but, when dissolved in n-hexane and ice-cooled, it partly crystallizes. As B and C are concentrated in the said crystalline substance, it may be said that the B and C are liable to crystallize easily.
(2) Gas chromatographic mass spectrometry analysis
Each mass spectrum was obtained through maesurement under the same conditions as in the gas chromatography to show a molecular ion M + 168 (C 11 H 20 O) and a closely similar mass spectral pattern in every case. The presence of dehydrated peak M + -18 (M/Z 150) existing when ionized proved the presence of a hydroxyl group.
(3) NMR spectrum
C 13 -NMR spectrum was taken in a deuterichloroform solution in the same manner as in the above Example 1. By corresponding an approximate concentration of each component from gas chromatogram to each peak strength in the C 13 -NMR spectrum, carbon atoms in respective A, B, C and D components were assigned to chemical shift of some peaks. Moreover, assignment to each component became clear from chemical shift of the carbon which the 2-hydroxyl group is particularly attached to, whereby structures of 4 components were confirmed. Namely, where the 4-methyl group is exo and the 8-methyl group is endo, it is believed that γ-effect can be induced by C 13 -chemical shift at the 2-position and thus a high magnetic field of 3 to 6 ppm can be induced. Then, the component D with the highest magnetic field is the 4-exo, 8-endo component of the formula [IA'-b], while the component A with the lowest magnetic field is the 4-endo, 8-exo compound of the formula [IA'-c]. As the compound before hydrogenation was a 1:1 mixture of the 4-exo and 4-endo types, steric configuration at the 4-position should be identical between the component A and the component C or between the component B and the component D. Accordingly, it has been determined that the component B is the 4-exo, 8-exo compound of the formula [IA'-a] and the component C is the 4-endo, 8-endo compound of the formula [IA'-d].
39 Numbers of chemical shift peaks were detected, while two of them were overlapped. With regard to methyl groups located at the 4- and 8-positions, a total of 8 peaks was to be detected, but 3 of them were equivalent. Thus, 5 methyl groups were observed. A sort of carbons was classified according to an INEPT method.
EXAMPLE 3
Following the same reaction procedures as in Example 1 except that 15 g of (-)-limonene aldehyde [[α] D 25 =-48.7° (c=2.1, CHCl 3 )] were employed, there were obtained 12.5 g of (1S,2S,5S)-4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol, which had a camphor-like smell.
b.p.: 83°-84° C./0.4 mmHg (Yield: 83.3%),
[α] D 25 =-84.4° (c=2.0, CHCl 3 ).
This compound is in an enantiomerism relationship with the compound as obtained in Example 1 and analytical results of gas chromatography, gas chromatographic mass spectrometry analysis, infrared absorption spectrum and NMR spectrum of this compound were identical with those of the compound obtained in Example 1.
EXAMPLE 4
Following the same reaction procedures as in Example 2 except that 6.0 g of (1S,2S,5S)-4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol obtained in Example 3 were employed, there were obtained 5.7 g of (1S,2S,5S)-4,8-dimethylbicyclo[3.3.1]nona-2-ol as a semi-crystalline substance, which had a menthol-like smell.
This compound is in an enantiomerism relationship with the compound as obtained in Example 2 and analytical results of gas chromatography, gas chromatographic mass spectrometry analysis, infrared absorption spectrum and NMR spectrum of this compound were identical with those of the compound obtained in Example 2.
EXAMPLE 5
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl isopropyl ether [IB]
To a solution of 10 g (60.2 mmol) of (+)-limonene aldehyde in 40 ml of isopropyl alcohol was added 1 g of Amberlyst 15 (produced by Rohm & Haas Co.) as a strongly acidic cation exchange resin and the resulting mixture was heated under reflux for 15 hours. After cooling, the Amberlyst 15 was filtered off and then the isopropyl alcohol was distilled off. The residue was subjected to column chromatography and eluate with toluene gave 10.4 g of the title compound, which had a sweet, camphor-like smell.
Yield: 83%, n D 23 =1.4747
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.17 (6H, d), 1.1-2.8 (12H, m), 3.5 (1H, m), 3.72 (1H, qq), 5.5 (1H, m).
IR (liquid film) cm -1 ; 2950, 2910, 2870, 1660, 1447, 1374, 1361, 1330, 1170, 1141, 1121, 1095, 1080, 1060, 983, 800.
EXAMPLES 6
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl ethyl ether [IB]
Following the same procedures as in Example 5 except that there were employed 16.6 g (100 mmol) of (+)-limonene aldehyde, there were obtained 16.5 g of the title compound, which had a fresh, refrigerant and pinene-like smell.
Yield: 85%, n D 23 =1.4813
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.18 (3H, t), 1.1-2.8 (12H, m), 3.3 (1H, m), 3.5 (2H, q), 5.5 (1H, m).
IR (liquid film) cm -1 ; 2930, 2900, 2860, 1660, 1442, 1365, 1341, 1105, 1074, 800.
EXAMPLE 7
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl isoamyl ether [IB]
Following the same procedures as in Example 5 except that there were employed 16.6 g (100 mmol) of (-)-limonene aldehyde, there were obtained 19.1 g of the title compound, which had a fresh and camphor-like smell.
Yield: 81%, n D 23 =1.4768
NMR (CDCl 3 ) δ ppm; 0.95 (9H, d), 1.0-2.8 (15H, m), 3.3 (1H, m), 3.45 (2H, t), 5.5 (1H, m).
IR (liquid film) cm -1 ; 2950, 2910, 2880, 1660, 1450, 1362, 1348, 1100, 800.
EXAMPLE 8
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl methyl ether [IB]
To a solution of 10 g (60.2 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol [IA] in 60 ml of tetrahydrofuran were added 1.3 g (56.5 mmol) of sodium and the resulting mixture was heated with stirring at 40° C. After the sodium was dissolved, 12.8 g (90 mmol) of methyl iodide were added dropwise and the resulting mixture was heated with stirring at 40° C. for 10 hours. After cooling, the tetrahydrofuran was distilled off under reduced pressure, the residue was subjected to column chromatography and eluate with toluene gave 7.8 g of the title compound, which had a refrigerant and camphor-like smell.
Yield: 72%, n D 23 =1.4867
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.0-2.8 (12H, m), 3.37 (3H, s), 3.5 (1H, m), 5.5 (1H, m).
IR (liquid film) cm -1 ; 2910, 2870, 2810, 1660, 1445, 1370, 1190, 1100, 798.
EXAMPLE 9
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-2-yl methyl ether [IB']
To a solution of 1 g (5.6 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl methyl ether [IB] in 10 ml of ethanol was added 0.1 g of 5% of Pd/C and the resulting mixture was heated with stirring at a hydrogen pressure of 20 atm and a reaction temperature of 70° C. for 6 hours. After cooling, the Pd/C was filtered off and the ethanol was distilled off under reduced pressure. The residue was subjected to column chromatography and eluate with toluene gave 0.95 g of the title compound, which had a camphor-like smell.
Yield: 94%, n D 23 =1.4751
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.0-2.8 (15H, m), 3.33 (3H, s), 3.5 (1H, m).
IR (liquid film) cm -1 ; 2950, 2910, 2860, 1480, 1450, 1372, 1190, 1105, 990.
EXAMPLE 10
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl acetate [IC]
To a solution of 10 g (60.2 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol [IA] in 40 ml of tetrahydrofuran were added 6.8 g (66.6 mmol) of acetic anhydride and 5.2 g (65.7 mmol) of pyridine and the resulting mixture was heated under reflux for 5 hours. After cooling, the tetrahydrofuran was distilled off, the residue was subjected to column chromatography and eluate with toluene gave 10.9 g of the title compound, which had a woody-like smell.
Yield: 87%, n D 23 =1.4850
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.1-2.3 (10H, m), 2.03 (3H, s), 2.4 (2H, m), 5.0 (1H, m), 5.6 (1H, m).
IR (liquid film) cm -1 ; 3000, 2950, 2920, 2830, 1730, 1450, 1375, 1363, 1245, 1053, 1025, 800.
EXAMPLE 11
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-2-yl acetate [IC']
Following the same procedures as in Example 10, 11.5 g of the title compound were obtained from 10.0 g (59.4 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-2-ol [IA']. This compound had a woody-like smell.
Yield: 92%, n D 23 =1.4754
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.12 (3H, d), 1.1-2.8 (12H, m), 2.01 (3H, s), 5.1 (1H, m).
IR (liquid film) cm -1 ; 2950, 2925, 2870, 1740, 1482, 1450, 1370, 1243, 1025.
EXAMPLE 12
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-yl propionate [IC]
Following the same procedures as in Example 10 except that propionyl chloride was employed in place of acetic anhydride, 6.0 g of the title compound were obtained from 5.0 g (30.1 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-ol [IA]. This compound had a woody-like smell.
Yield: 90%, n D 23 =1.4821
NMR (CDCl 3 ) δ ppm; 0.95 (3H, d), 1.16 (3H, t), 1.1-2.8 (12H, m), 2.02 (2H, q), 5.1 (1H, m), 5.6 (1H, m).
IR (liquid film) cm -1 ; 2930, 2910, 2870, 2825, 1730, 1450, 1372, 1353, 1340, 1180, 1075, 1010, 800.
EXAMPLE 13
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-7-en-2-one [ID]
To a solution of 5 g (30.1 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-2-ol [IA] in 30 ml of acetone was added dropwise a solution of 6 g (60.2 mmol) of chromic acid in 20 ml of 20% sulfuric acid and the resulting mixture was stirred at 0° C. for 3 hours. To the reaction mixture were added 100 ml of water and the resulting mixture was extracted with 30 ml of toluene. The toluene was distilled off under reduced pressure, the residue was subjected to column chromatography and eluate with toluene gave 4.2 g of the title compound, which had a fruity, jasmine-like smell.
Yield: 85%, n D 23 =1.5030
NMR (CDCl 3 ) δ ppm; 1.06 (3H, d), 1.4-3.2 (12H, m), 5.6 (1H, m).
IR (liquid film) cm -1 ; 2940, 2900, 1703, 1660, 1442, 1375, 1270, 1220, 808.
EXAMPLE 14
Synthesis of 4,8-dimethylbicyclo[3.3.1]nona-2-one [ID']
Following the same procedures as in Example 13, 10.0 g (60.2 mmol) of 4,8-dimethylbicyclo[3.3.1]nona-2-ol [IA'] gave 8.0 g of the title compound, which had a floral, menthol-like smell.
Yield: 81%, n D 23 =1.4852
NMR (CDCl 3 ) δ ppm; 0.87 (3H, d), 1.07 (3H, d), 1.0-2.8 (12H, m).
IR (liquid film) cm -1 ; 2940, 2910, 2860, 1770, 1450, 1410, 1374, 1237. | There is disclosed a novel 4,8-dimethylbicyclo[3.3.1]nonane derivative represented by the formula [I]: ##STR1## wherein X and Y have the same meanings as defined in the specification. The compound of the present invention has an unique and strong perfume and hence is expected to be useful as perfumery. | 2 |
RELATED APPLICATION
This application is a national stage entry of PCT/US2012/021989, filed Jan. 20, 2012 which claims priority from provisional application 61/439978, which are incorporated by reference in their entirety
BACKGROUND
1. Field Of The Invention
This invention pertains to a durable anti-wear composition (coating), a method of making the anti-wear composition, and a method of using the anti-wear composition to treat metal components subject to frictional wear such as bearings. The composition and method of use make it possible to selectively optimize the clearances between any bearing surface (ferrous or nonferrous), and to obtain high carbonization of ferrous surfaces by impregnating the surface layers with carbon (by growing monocrystals) during the standard operating process of the mechanism without disassembly or with only partial disassembly.
2. Description of the Related Art
In recent years, a number of metal treatment products have appeared which use solid lubricant additives, including natural magnesium hydro-silicates such as Serpentine and Talc, to form coatings on rubbing surfaces. When these minerals are manufactured into a solid lubricant additive under specific conditions, mixed with binders between the rubbing surfaces, and burnt-in during normal operation causing the formation of a coating on the rubbing metal surfaces, significant changes in the wear of the rubbing surfaces have been observed.
There is also a known method of forming a coating on rubbing surfaces involving a pre-activated mixture of abrasive-like powder in an organic binder placed between the rubbing surfaces of elements of a friction pair. Once placed between the rubbing surfaces, the coating is burned-in during normal operation. The activated mixture contains the following ingredients with a dispersity (size range) of 0.1-2μ:
Serpentinite
0.5-40.0%
mass,
Sulfur
0.1-5.0%
mass, and
Surfactant
1.0-55.0%
mass
Also known is a method of forming a coating on rubbing surfaces consisting of grinding a mixture of raw minerals containing Serpentine, Enstatite and Magnetite or a combination of them, with at least one mineral selected from Amphibole, Biotite, Ilmenite, Pentlandite, Pyrrhotite, Talc, Chalcopyrite or native Sulfur, to a dispersity of 0.01-1.0μ. After the mechanical activation of the resulting solid lubricant additive with a binder is completed, the finished composition is placed between the rubbing surfaces and burnt-in. The composition make-up is:
mineral mixture 3.3% mass and binder 96.7% mass.
This known method makes it possible to increase the mechanical strength of the surface of the metal, reduce the friction coefficient, eliminate surface defects and increase anticorrosive durability. However, this known method does not ensure the formation of a layer firmly bonded to the friction surface.
Thus there remains a need for a metal treatment additive that, when exposed to the heat of friction of metal rubbing surfaces, reacts with the metal surfaces to form a “mono-crystalline metallic” (diamond like) layer which decreases the wear of the rubbing surfaces and minimizes the friction coefficient.
SUMMARY OF THE INVENTION
This invention pertains to a durable anti-wear metal treatment composition (also known as a solid lubricant additive), a method of making a durable anti-wear metal treatment composition, and a method of using the metal treatment composition to form a durable anti-wear coating in friction assemblies. The metal treatment composition makes it possible to selectively optimize the clearances between any bearing surface (ferrous or nonferrous), and to obtain high carbonization of ferrous surfaces by impregnating the surface layer with carbon (monocrystals) during the standard operation of the mechanism without disassembly or with only partial disassembly.
The metal treatment composition includes a binder and a solid additive. In one embodiment the solid additive is made from a variety of natural minerals that are mixed in an elemental consistency in the following amounts:
Silicon (Si)
52.0-58.2%
weight,
Magnesium (Mg)
34.6-38.8%
weight,
Iron (Fe)
1.9-5.2%
weight,
Aluminum (Al)
0.35-3.5%
weight,
Chromium (Cr)
0.35-1.75%
weight,
Nickel (Ni)
0.15-1.75%
weight,
Calcium (Ca)
0.1-0.9%
weight,
Manganese (Mn)
0.04-0.2%
weight, and
Titanium (Ti)
0.04-0.15%
weight.
The method of making the metal treatment composition comprises the steps of grinding raw natural materials such as those listed above into a solid additive, removing impurities and oxides from the solid additive, and mechanically activating the solid additive with a binder. The method creates a powdered solid lubricant additive with a dispersity (size range) of 500 nm-40 microns.
The method of using the metal treatment composition comprises the steps of providing a metal treatment composition as described above; applying the metal treatment composition between the rubbing surfaces of a bearing or other mechanism; and burning-in the metal treatment composition during normal operation of the mechanism or though ultrasonic vibration by raising the temperature of the rubbing surfaces or other mechanical methods.
It is believed that, during the burning-in process, particles and nanoparticles of the solid additive are built up in the voids and depressions of the bearing (wear) surfaces, causing thin layers to merge with the bearing surface at the molecular level. The resulting mono crystalline/metallic surface becomes much harder and smoother than the worn surfaces, resulting is significantly less friction.
The finely dispersed and mechanically activated solid additive is a catalyst for growing mono-crystals on the bearing surfaces of metals in friction pairs, contributing to a change in the crystal lattice of the surface layer, carbonization of the surface layer on ferrous metals, and selectively compensates for clearance gap. In nonferrous metals, the surface hardness does not change but a selective optimization of clearance gaps still occurs.
During testing of the solid lubricant additive of the present invention a decrease in the friction coefficient of rubbing surfaces has been observed. Use of the additive also increased the surfaces' resistance to wear and lengthened service life, allowing for carbonization of the surface layer on cast iron and steel, optimization of clearance gaps in friction pairs, and the ability to repeatedly use the technology with only small amounts of solid lubricant additive added. As a result, a decrease in consumption of electrical power and fuel and an order of magnitude increase in service life of assemblies and mechanisms were seen.
DETAILED DESCRIPTION OF THE INVENTION
While this invention may be embodied in many forms, there will herein be described in detail one or more embodiments with the understanding that this disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the invention to the illustrated embodiments.
The invention pertains to manufacturing, operation of machines and mechanisms, and energy and resource-conservation technologies. In particular, the invention pertains to a durable anti-wear metal treatment composition (also known as a solid lubricant additive), a method of making a durable anti-wear metal treatment composition, and a method of using the metal treatment composition to form a durable anti-wear coating in friction assemblies.
I. Metal Treatment Composition (a.k.a. Solid Lubricant Additive)
In one embodiment the metal treatment composition comprises a solid additive and a binder. More particularly, the metal treatment composition may comprise from about 0.0025% to about 0.5% by weight of a solid additive, and from about 99.9975% to about 99.5% by weight binder.
The binder may comprise one or more of motor oil, industrial oil, fuel, mineral oil, synthetic oils and grease. The solid lubricant additive can be used with any of the following binders: oil (motor, industrial, and other), fuel, mineral oils (liquid mixtures of high-boiling hydrocarbons, with a boiling temperature of 300-600° C.), synthetic oils (silicon-organic liquids, ethers of phosphoric, adipic, polyalkylene glycols, and others), cup grease, and any surfactants used as dispersers during grinding.
The solid additive may comprise from about 85% to about 100% by weight varieties of natural minerals and from about 0% to about 15% by weight surfactant.
The varieties of the natural minerals may comprise:
40-70% Mg 6 [Si 4 O 10 ](OH) 8 by weight, 5-20% Al 2 [Si 4 O 10 ](OH) 2 by weight, 5-10% Amphibole by weight, and 20-40% Mg 3 [Si 2 O 5 ](OH) 4 by weight.
In another embodiment the varieties of natural minerals may comprise the following, and may be mixed in an elemental consistency, according to an x-ray diffraction analysis as follows:
Silicon (Si) 52.0-58.2% weight, Magnesium (Mg) 34.6-38.8% weight, Iron (Fe) 1.9-5.2% weight, Aluminum (Al) 0.35-3.5% weight, Chromium (Cr) 0.35-1.75% weight, Nickel (Ni) 0.15-1.75% weight, Calcium (Ca) 0.1-0.9% weight, Manganese (Mn) 0.04-0.2% weight, and Titanium (Ti) 0.04-0.15% weight.
II. Method of Making the Metal Treatment Composition
A method of making the metal treatment composition is also provided, comprising the steps of grinding of the raw natural materials into a solid additive, removing impurities and oxides from the solid additive, and mechanically activating the solid additive with a binder. The method creates a powdered solid lubricant additive with a dispersity of 500 nm-40μ(microns).
The raw materials are ground to obtain a finely-dispersed powder with a dispersity of 500 nm to 40μ. Experimental data show that the dispersity of the composition is determined by the area of application. Therefore, the grinding of the raw minerals mixture may be done in five variants of dispersity:
1) Nano-powder with a dispersity of up to 500 nm—universal use;
2) Not more than 5μ—for fuel, hydraulic and special precision systems;
3) Not more than 10μ—for internal combustion engines;
4) Not more than 28μ—for circulating lubrication systems and bearings;
5) Not more than 40μ—for gear and chain transmissions and open-type mechanisms (pinion gears, chain transmissions).
Subsequently, the solid additive powder is mechanically activated with the binder. The finely-dispersed, mechanically activated solid additive is a catalyst for:
(1) The process of growing single crystals on the metal surface of friction pairs, contributing to a change in the crystal lattice of the metal's surface layer of friction pairs; (2) Carbonization of the surface layer of ferrous metals (the hardness does not change in nonferrous metals), and (3) Selective optimization of clearances between friction surfaces.
EXAMPLE 1
Method of Making a Metal Treatment Composition
Raw materials were ground into a solid additive and impurities and oxides were removed. The raw materials were a mixture containing modified forms of Ophites, Antigorite, Chrysotile, Orthochrsotile, and a small amount of Clinochrysotile and Lizardite. The resulting composition had an elemental consistency, according to an x-ray diffraction analysis, of:
Silicon (Si)
52.0-58.2%
weight,
Magnesium (Mg)
34.6-38.8%
weight,
Iron (Fe)
1.9-5.2%
weight,
Aluminum (Al)
0.35-3.5%
weight,
Chromium (Cr)
0.35-1.75%
weight,
Nickel (Ni)
0.15-1.75%
weight,
Calcium (Ca)
0.1-0.9%
weight,
Manganese (Mn)
0.04-0.2%
weight, and
Titanium (Ti)
0.04-0.15%
weight.
The components were mixed in an attrition mill under a controlled beating rate. The solid lubricant composition was subjected to mechanical activation by ultrasound or another method with a binder base of various oils or semisolid lubricants in the following ratio of:
solid lubricant additive 0.02% mass and binder 99.98% mass.
III. Method of Use
A method of treating rubbing surfaces is also provided, comprising the following steps:
providing the metal treatment composition described above;
introducing (placing) the metal treatment composition between the rubbing surfaces of a friction assembly; and
burning-in during normal operation of the mechanism or though ultrasonic vibration by raising the temperature of the rubbing surfaces.
The introduction of the activated solid lubricant additive (with a binder) into the friction assembly may be done through the normal lubrication (fuel supply or oil supply) system or by a technique of spray-coating the surface of the contact area at a specific frequency with subsequent brief break-in at normal loads and speeds for even distribution.
The main burn-in process may occur during normal operation of the mechanism.
The metal treatment method results in (1) the formation of an anti-wear coating, (2) selective carbonization of the surface layer, and (3) optimization of clearance gaps between the rubbing surfaces of the fuel, hydraulic, and precision systems, gear and chain transmissions, circulating lubrication systems and rolling and plain bearings. The tri-technical effect of the solid additive is achieved equally with different binders and surfactants due to the qualitative and quantitative compositions of the natural mineral mixture.
Combinations of these processes are accompanied by an intensive cleaning of the surface layer of contaminants and the formation of a clearly expressed regular structure on the surface coat with an obvious improvement in the rheology, load capacity, durability, and a decrease in the coefficient of friction.
The metal treatment composition may be used in internal combustion engines, presses, hydraulic pumps, compressors and other mechanisms used in various sectors of industry and agriculture.
On ferrous alloys, thermal x-ray studies have shown that, under pressure of high loads and temperatures in the bearing contact zones, water of crystallization in the composition of crystal hydrates is replaced by carbon atoms from the hydrocarbon binder penetrating into the surface of the metal. With loss of the water of crystallization, the crystals become simultaneously a catalyst for the process of carbonizing the surface layer and a skeleton for buildup of the surface coat. The saturation of the surface layer of the metal with carbon forms a surface layer coating, which is made up of Mg, Al, Si, S, Sn, K, Cl, Ca.
On nonferrous alloys, the surface geometry changes by forming a super-hard silicon carbide layer, characterized by a gray transparent color being the crystal product of carbon compounds. According to spectral analysis, the silicon carbide surface layer is made up of 25% Sn and 75% Al.
INITIAL TESTS
In a test made using an internal combustion engine of a GAZ-3221 motor vehicle from the Volga Motor Plant, it was found that 0.1-0.2 grams of the solid lubricant additive is sufficient to obtain the necessary results.
Only 2.5-7.5 grams of the solid lubricant additive was needed for the 6 VD 26/20 AL-1 diesel engine on a ship's auxiliary power unit (APU). The dosage is calculated depending on the degree of wear of the power-generating unit. Tests conducted on an SKL 6 VD 26/20 Al-1 auxiliary diesel engine on the ship “N. Chernyshevskiy”, belonging to the company OJSC Volga-Flot, showed that during the navigation period, instead of wear, the condition of the engine and the fuel group improved. Compression on all cylinders increased indicating a process of restoration of the cylinder-piston group. The atomizer spray became sharp, without dripping. Fuel consumption decreased 7.3% at a load of 100 kW.
Similar tests were conducted on the Project 302 passenger ship “Leonid Krasin”, built in 1989, the length of which is 129 m, breadth—16.7 m, depth—5.3 m, and a passenger capacity of 332 people. Compressor No. 13121 on this ship demonstrated a 25% increased efficiency with a decrease in electrical power consumption from 70 to 67 amperes. The tests were conducted by the head of the fleet testing group of OJSC Mosturflot, Certification of Recognition of the Federal State Institution Russian River Registry No. 1349 of 06.09.2005, D. B Kalinin.
The tests conducted on the Central Heating and Power Plant—26 of OJSC MOSENERGO jointly with specialists of RAO EES ROSSII and OJSC Firm ORGRES showed the overall efficiency of their compressor was increased from 67% to 76.8%.
At the Nizhegorod GES (Hydroelectric Power Plan), a similar compressor produced a “thermal wedge” 15 minutes after being turned on. After application of the technology, the nadirs disappeared on the cylinder surfaces, electric power consumption was reduced, and productivity doubled.
According to the results of disk-plate tests to determine the wear on bearing surfaces in machines treated with a small amount of solid lubricant additive, an increase in mass was observed instead of a decrease, as expected during normal wear.
After 30-40 minutes of operating a friction pair under load, a chemical spectral analysis did not find the presence of the solid lubricant additive in the oil. Additionally, according to the results of a spectral analysis, the wear products disappeared from the oil. This indicates that the solid additive is acting as a catalyst during the process of transferring particles at the molecular level.
As a result of all the testing, it was established that an increase of up to 10% in cylinder compression , a reduction in the fuel consumption for the diesel generator up to 2.5 kg/hour at a 100 kW, a decrease in the intensity of vibration at the engine block and support structure of up to 11.3% and 10.6% respectively.
Additional Testing—12 Liter Engine Truck
A truck (Engine Model: E7355380, 12 Liter) was tested to establish a reference baseline of performance. After the baseline test, the solid lubricant additive was added to the fuel system and the crankcase. The truck was put back into normal service. It was tested again after 9486 miles and 260 hours of operation.
Both tests were done in a truck yard and not under load. There were two significant data points taken during each test: at idle (600-650 RPM), and at 1000 RPM. The results are shown below:
Date
26-May
23-Jun
Mileage
906,674
916,160
9,486
Hours
30,427.40
30,687.40
260.0
Engine Temp: ° F.
160
165
Consumption at Idle: Liters/Hour
1.9
1.7
10.5%
Consumption at
4.0
3.4
15.0%
1000 RPM: Liters/Hour
The Estimated Annual Cost Savings was determined to be % 13,271.78 as calculated below:
Miles driven between tests (28 days)
9,486
Pro-rated for one month (30 days)
10,164
Ave mileage of truck (MPG)
5.5
Ave Gallons of fuel per month
1848
Ave cost for gallon of fuel
$3.99
Ave cost of fuel per month
$7,373.21
Estimated % Saving fuel consumption
15.0%
Ave Cost Saving per month
$1,105.98
Ave Cost Saving per year
$13,271.78
The results indicate up to 15% improvement in fuel consumption. This test was done with the truck parked and not on the highway under load. Under full load at peak torque, pulling 20 to 24 tons of load, this engine would likely consume up to 30 liters per hour.
It is believed that the solid lubricant additive works by restoring the geometry of the bearing surfaces by filling the pits and voids and polishing the frictional surfaces. The surfaces become very hard and smooth, thereby reducing friction. The reduction of friction reduces wear and heat, resulting in a smoother running engine with more horsepower. Another benefit of the present method is longer time between overhauls. Any additional power achieved will help the driver by eliminating or reducing downshifting when pulling a load up a grade. Still another benefit is reduced fuel consumption.
Although the solid lubricant additive was only added to the engine fuel system and crankcase, it could also be added to the transmission(s), differential(s), and wheel bearings. In all cases it would restore the bearing surfaces and reduce friction and wear. The truck as a whole would run better, have more power, less heat, less wear, less time between major overhauls, and better mileage.
Additional Testing—1998 Honda Civic
A test was made using a 4 cylinder 1998 Honda Civic automobile. Before adding the solid lubricant additive the car had very poor compression which was different for each cylinder. The solid lubricant additive as applied and measurements were repeated after 756 miles. The results are shown on the following table:
Cylinder
1
2
3
4
Mileage
Compression
PSI
PSI
PSI
PSI
147.7
132.1
129.2
127.8
146,868
149.1
149.1
149.1
149.1
147,624
It is understood that the embodiments of the invention described above are only particular examples which serve to illustrate the principles of the invention. Modifications and alternative embodiments of the invention are contemplated which do not depart from the scope of the invention as defined by the foregoing teachings and appended claims. It is intended that the claims cover all such modifications and alternative embodiments that fall within their scope. | A durable anti-wear coating for friction assemblies, a method of making the same and a method of using the same is provided. The method of use results in the formation of an anti-wear coating and selective carbonization of any ferrous surfaces by impregnating the surface layer with carbon, and makes it possible to selectively optimize the clearances between any bearing surface (ferrous or nonferrous). The method may take place during the standard operating process of the mechanism, without disassembly or with only partial disassembly. | 2 |
1) FIELD OF THE INVENTION
[0001] The present invention relates to a bonded nonwoven having extensible fibers for use in articles such as diapers and other hygienic articles, wipes, interlinings and other articles requiring some degree of elasticity. Specifically it relates to bicomponent fibers where one component is an elastic thermoplastic and another component employed as a binder having a lower melting point than the elastic component. On bonding the binder melts to form bonding points exposing the elastic core.
2) PRIOR ART
[0002] In numerous disposable articles, nonwovens require some extensibility. In diapers an extensible nonwoven provides a more comfortable article with reduced leakage. In sanitary articles that consist of wood pulp and super absorbent polymers (SAP) for absorbency, an extensible nonwoven core allows the absorbent to swell to its full potential without being restricted by an inelastic core, like commercially available nonwovens on the market today. In wipes the presence of extensibility makes the product more drapable and less paper-like. In interlinings a more extensible nonwoven again gives a more textile feel to the product.
[0003] Elastomers used for elastic films often have an undesirable rubbery feel. When the substances are used in composite nonwovens, the user in contact with the fabric has a rubbery or sticky feeling which is undesirable for direct contact with the skin.
[0004] Elastic fabrics usually comprise elastic nonwovens or layers of elastic film. When elastic films are used and the fabric needs to breathe, it is conventional to make holes in the films. These holes may weaken the film and, when stretched, may constitute a site from where tears propagate in the film. Thin films are desirable economically but have limited strength, and this limitation is complicated by the presence of holes.
[0005] One method to meet the need for elasticity and for good contact with the skin, is to place a layer of fibrous nonwoven fabric on the elastic layer, producing a composite fabric having improved properties. The nonwoven fabric gives a surface covering the elastomeric layer a soft hand, that is capable of breathing, and suitable for direct contact with the skin. The nonwoven layer also gives additional strength to composite materials. Solutions of this kind are described in U.S. Pat. Nos. 5,921,973; 5,853,881; 5,709,921; 5,681,645; 5,413,849 and 5,334,446.
[0006] The composite fabric has to be made in a number of operations with expensive equipment and raw material, including the elastic substances, nonwovens and adhesives.
[0007] U.S. Pat. No. 6,541,403 B2 to Billarant et al. discloses the use of a bicomponent fiber having an elastic core surrounded by a non-elastic sheath. The sheath is cut or broken at regular intervals to expose and activate the elastic core.
[0008] U.S. Pat. No. 5,352,518 to Muramoto et al. discloses a composite fiber having an elastic core and a sheath that has numerous ridges rising circumferentially and along the length of the fiber. This elastic fiber is not used as a binder fiber in nonwovens, but as a rough elastic fiber for knitted or woven goods.
[0009] U.S. Pat. No. 6,225,243 to Austin discloses the use of bicomponent filaments containing an elastic core for use in a spunbond or melt blown nonwoven process.
[0010] European Pat. Application 0 454 160 A2 discloses a bicomponent filament comprised of a thermoplastic non-elastomer sheath and a cross-linked polyurethane core. These filaments are used for support type stockings, and no reference is given to their use in nonwoven articles.
[0011] Japan Publication 09-031751 discloses a bicomponent fiber comprised of a lower melting non-elastic sheath and an elastic core. The sheath component comprises more than 50% by weight of the fiber and a side-by-side or eccentric configuration is preferred to form crimps in the fiber. These crimped fibers are carded, needle punched and hot air bonded to form an elastic nonwoven article. This publication does not mention a nonwoven having an absorbent.
[0012] Japan Publication 2000-282331 discloses a bicomponent fiber comprised of a thin sheath (less than 20% by volume) of a lower melting sheath and an elastic core. This was aimed at protecting the elastic core such that it spun and drew easily to a staple product that could be carded and bonded into a resilient cushion.
[0013] Although the dual property of bonding and elasticity in bicomponent fibers with a thermoplastic elastomeric core and a low melting sheath has been disclosed in the Japanese publications, these did not disclose their value in nonwoven structures containing an absorbent such as wood pulp and/or SAP. These publications did not recognize the problem and certainly cannot share in the solution. In addition to the longer fibers required for carded nonwovens there is a need for extensible fibers for use in dry laid and wet laid processes in which short ¼ (0.635 cm) to ½ (1.27 cm) inch fibers are used.
SUMMARY OF THE INVENTION
[0014] The present invention, in its broadest sense, comprises a nonwoven article produced from a blend of an extensible bicomponent fiber, an absorbent and optionally other binder and synthetic fibers. The preferred extensible bicomponent fiber comprises a thermoplastic elastomer as the core, and a thermoplastic sheath having a lower melting point than the core. However a side-by-side bicomponent fiber is also within the scope of the present invention. The present invention, in particular, comprises a nonwoven article or a component thereof, prepared by wet or dry laid processes, utilizing an extensible bicomponent fiber whose sheath melts on heating, thus bonding the nonwoven web and exposes the elastomeric core.
[0015] In the broadest sense, the present invention contemplates a bonded nonwoven article comprising a blend of extensible bicomponent fibers, an absorbent, and optionally nonextensible bicomponent fibers, or synthetic fibers, or both.
[0016] In the broadest sense the present invention also contemplates a method of producing a nonwoven web by mixing the fibers described above, either by the dry laid or wet laid process, and heating the mixture to bond the fibers into a nonwoven web that can be used to produce a nonwoven article or a component thereof.
[0017] In the broadest sense, the present invention also contemplates a diaper that includes as a component a bonded nonwoven web. Such a diaper being an improvement over present day diapers because the extensible fibers allow the diaper to expand as the absorbent swells to its full capacity.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Nonwoven webs of the present invention can be made by either dry laid or wet laid processes. Dry laid webs are made by the airlay, carding, garneting, or random carding processes. Air laid webs are created by introducing the fibers into an air current, which uniformly mixes the fibers and then deposits them on a surface. The carding process separates tufts into individual fibers by combing or raking the fibers into a parallel alignment. Garneting is similar to carding in that the fibers are combed. Thereafter the combed fibers are interlocked to form a web. Multiple webs can be overlapped/stacked to build up a desired weight. Random carding uses centrifugal force to throw fibers into a web with random orientation of the fibers. Again multilayers can be created to obtain the desired web weight. The dry laid components are then bonded together by heating. Wet laid webs are made by a modified papermaking process in which the fibers are suspended in water (or other liquid), the water is separated on a screen to form a web, and the web is dried and bonded by heating.
[0019] The webs are bonded using the low melt component (binder) of the bicomponent fibers. The fibers (bicomponent fibers and optionally synthetic fibers) and absorbent can be bonded together to form a web, by thermal means. Thermal bonding in an oven (hot air, radiant or microwave), or heated calendar roll(s), or by ultrasonic energy, melts the low melt component of the bicomponent fibers. The low melt component flows to and coalesces at the junction of the various fibers. Next, the web is cooled thereby solidifying the melted binder. The web now has a sufficient rigid structure to be useful as a component of nonwoven article, or the article itself.
[0020] Suitable absorbents are natural or synthetic absorbents. Synthetic absorbents are primarily known as super absorbent polymers (SAP). Natural absorbents are hydrophilic materials such as cellulosic fibers, wood pulp fluff (also known as wood pulp fibers), cotton, cotton linters, and regenerated cellulose fibers such as rayon, or a mixture of these. Preferred is wood pulp fluff, which is both inexpensive and readily available. As used herein, the term “super absorbent polymer” or “SAP” refers to a water-swellable, generally water-insoluble material capable of absorbing at least about 10, desirably about 20, and preferably about 50 times or more its weight in water. The super absorbent polymer may be formed from organic material, which may include natural materials such as agar, pectin, and guar gum, as well as synthetic materials such as synthetic hydrogel polymers. Synthetic hydrogel polymers include, for example, carboxymethyl cellulose, alkali metal salts of polyacrylic acid, polyacrylamides, polyvinyl alcohol, ethylene maleic anhydride copolymers, polyvinyl ethers, hydroxypropyl cellulose, polyvinyl morpholinone, polymers and copolymers of vinyl sulfonic acid, polyacrylates, polyacrylamides, polyvinyl pyridine, and the like. Other suitable polymers include hydrolyzed acrylonitrile grafted starch, acrylic acid grafted starch, and isobutylene maleic anhydride copolymers and mixtures thereof. The hydrogel polymers are preferably lightly crosslinked to render the materials substantially water insoluble. Crosslinking may, for example, be by irradiation or covalent, ionic, van der Waals, or hydrogen bonding. Suitable materials are available from various commercial vendors such as the Dow Chemical Company, Allied Colloid, Inc., and Stockhausen, Inc. The super absorbent polymer may be in the form of particles, flakes, fibers, rods, films or any of a number of geometric forms.
[0021] Bicomponent fibers have a low melt component and a high melt component. The fibers can be the side-by-side type or the sheath-core type. Preferable are the sheath-core type. For extensible bicomponent fibers, the high melt component is the elastic thermoplastic, while the low melt component is further described later. For other bicomponent fibers, used as additional binder and/or non-extensible synthetic fiber, the high melt component is the non-extensible synthetic fiber. Again the low melt component is described later. The high melt component (of either the extensible or nonextensible bicomponent fibers) generally comprises from about 35 to about 65 wt. percent of the bicomponent fiber.
[0022] The core or high melt component of the extensible bicomponent fiber can be any thermoplastic elastomer. Elastomeric thermoplastic polymers include polyurethane elastomeric materials such as ELASTOLLAN sold by BASF, ESTANE sold by B.F. Goodrich Company, polyester elastomers such as HYTREL sold by E.I. Du Pont De Nemours Company, polyether-ester elastomeric materials such as ARNITEL sold by DSM; and polyether-amide materials such as PEBAX sold by Elf Atochem Company. Of these polyether-ester thermoplastics are preferred. Heterophasic block copolymers, such as those sold by Montel under the trade name CATALLOY are also advantageously employed in the invention. Other elastomeric polymers suitable for this invention are diblock and triblock copolymers based on polystyrene (S) and unsaturated or fully hydrogenated rubber blocks. The rubber blocks can consist of butadiene (B), isoprene (I), or the hydrogenated version, ethylene-butylene (EB). Thus, S-B, S-I, S-EB, as well as S-B-S, S-I-S, and S-EB-S block copolymers can be used. Preferred elastomers of this type include the KRATON polymers sold by Shell Chemical Company and the VECTOR polymers sold by DEXCO. Thermoplastic polyurethanes, which are obtained by reacting a high molecular weight diol and an organic diisocyanate, can also be utilized. The core can be made of materials such as sequenced copolymers, e.g. poly(ethylene-butene), poly(ethylene-hexene) poly(ethylene-propylene) poly(ethylene-octene), poly(styrene-butadiene-styrene), poly(styrene-ethylene and butylene-styrene), poly(styrene-isoprene-styrene), a poly(ester ether oxide), a poly(ether oxide-amide), poly(ethylene-vinyl acetate), poly(ethylene-methylacrylate), poly(ethylene-acrylic acid), poly(ethylene-butyl acrylate) or mixtures thereof.
[0023] The sheath polymer for the extensible bicomponent fibers should have a melting point at least about 10° C. below that of the core polymer. It is advantageous for the sheath polymer to rapidly flow during the bonding process so that the unmelted elastic core is exposed. Sheath polymers, as the low melt component, include polyolefin, such as polyethylene (PE), polypropylene (PP), polybutylene or a mixture of these. Suitable polyethylene may be high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ultra low density polyethylene (ULDPE); or a mixture of these. These polyolefins may be produced with either Ziegler-Natta or metallocene catalysts. For adhesion to cellulosic fibers such as wood pulp, it is preferred if the polyolefin sheath contains an adhesion promoter or tackifier.
[0024] Adhesion promoters are typically polyolefins grafted with maleic acid or maleic anhydride (MAH), both of which convert to succinic acid or succinic anhydride upon grafting to the polyolefin. The preferred incorporated MAH graft level is 10% by weight (by titration). Also, ethylene-acrylic copolymers, and a combination of this with the grafted polyolefins mentioned are suitable adhesion promoters. Commercially available maleic anhydride grafted polyethylene are known as ASPUN resins from Dow Chemical. Commercially available ethylene-acrylic copolymers are Bynel 2022, Bynel 21E533 and Fusabond MC 190D from DuPont, and the Escor acid terpolymers from ExxonMobil. The ethylene-acrylic copolymer comprises from about 1 to about 20% by weight based on the weight of the polyolefin polymer, and preferably from 5 to 15% by weight. The amount of grafted polyolefin adhesion promoter is such that the weight of incorporated maleic acid or maleic anhydride comprises from about 0.05% to about 2% by weight, and preferably from 0.1 to 1.5% based on the weight of the polyolefin polymer.
[0025] Tackifiers include rosin, rosin esters, and terpene based, piperylene based, and hydrocarbon based compounds. Commercially available rosin based tackifiers are known as Foral 85 made by Hercules, Inc.; Permalyn 2085 made by Eastman Chemicals; or Escorez 5400 made by Mobil Exxon Chemical. Commercially available terpene based tackifiers are Zonarez, Zonatac and Nirez from Arizona Chemical Company. Commercially available piperylene based tackifiers are Picotac and Hercotac available from Hercules, Inc. A commercially available hydrocarbon based tackifier is Escorez 5400 from ExxonMobil. The preferred tackifier is rosin ester, and most preferred is a glycerin ester of tall oil rosin. The tackifier preferably comprises from about 0.1 to about 40% by weight of the sheath polymer, and preferably 0.5 to 10%, and most preferably 1 to 5%.
[0026] Alternatively, the low melt component or sheath polymer can be a low melting polyester such as polybutylene terephthalate (PBT), or polytrimethylene terephthalate (PTT), a low melting copolyester such as copolymers of PET with comonomers such as suitable diol components selected from 1,4-cyclohexanedimenthanol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,2-dimenthyl-1,3-propanediol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, and diols containing one or more oxygen atoms in the chain, e.g., diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, or mixtures of these; or one or more diacid components other than terephthalic acid, (aliphatic, alicyclic, or aromatic dicarboxylic acids) such as isophthalic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, 1,12-dodecanedioic acid, 2,6-naphthalenedicarboxylic acid, bibenzoic acid, or mixtures of these.
[0027] The extensible bicomponent fibers can be of the type in which the low melting portion is adjacent to the high melting portion such as a side-by-side configuration, or a sheath-core configuration where the sheath is the low melting component and the core is the high melting component. The term “sheath” is used to designate the low melting component of the bicomponent fiber. Bicomponent fibers have an average length of from about 3 to about 75 mm, and a denier (decitex (dtex)) of between 1 (1.1) and 10 (11.1).
[0028] Nonextensible bicomponent fibers can be used in addition to the extensible bicomponent fiber. The sheath of these bicomponent fibers is selected from the same classes of polymers as noted for the extensible bicomponent fiber. The core or high melt component may be selected from the class of polyolefins, such as polypropylene, and polybutylene; polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate, and the like; polyamides such as nylon 6, nylon 66, and the like; polyacrylates such as polymethacrylate, polymethylmethacrylate, and the like; as well as mixtures and copolymers of these. The low melting component, in a nonextensible bicomponent fiber melts at a temperature of at least about 10° C. lower than the high melting portion.
[0029] Other synthetic fibers can be used in the preparation of the nonwoven web in addition to the extensible bicomponent fiber, nonextensible bicomponent fiber and absorbent. These fibers can be of any cross-section, for instance round, hollow or multilobal. Suitable synthetic fibers are polyester, polyolefin, nylon, polyacrylates and the like. These fibers are essentially the same as those for the high melt component of the nonextensible bicomponent. Thus an optional nonextensible bicomponent fiber can be a source of both a synthetic fiber, or a low melt binder component, or both. Preferred synthetic fibers are those made from PET.
[0030] The webs are made by merely mixing the bicomponent fibers and optional synthetic fibers with the absorbent in fiber form or otherwise, using dry laid or wet laid techniques. The absorbent is mixed with the bicomponent fiber such that the extensible bicomponent fibers comprises from about 5 to about 50 percent by weight of the total web, with the remainder being substantially the absorbent. The optional synthetic fibers can comprise up to half of the extensible bicomponent fibers (i.e. replace some of the extensible bicomponent fibers with synthetic fibers). When it is desirable to produce a web that requires synthetic fibers, it is usually necessary to add other nonextensible bicomponent fibers to act as the low melt binder and the synthetic fiber component. Thus the extensible bicomponent fiber can be the sole bicomponent fiber or mixed with nonextensible bicomponent fibers. In addition conventional synthetic fibers such as polyester can be mixed with the other fibers. The web compositions of the present invention can be layered until their weight is in the range from about 20 to about 500 grams per square meter (gsm), preferably from about 50 to about 250 gsm. Thereafter, the web may be cut into various lengths and widths for end use applications, namely, wipes, fenestration drapes, dental bibs, eye pads, diapers, incontinent pads, sanitary napkins, wound dressing pads, air filters, liquid filters and fabrics such as drapes, bedding, pillows, cushions and other insulating products.
Test Procedure
[0031] The wet and dry strength of the web was measured according to TAPPI test methods T 456 om-87 and T 494 om-88 respectively. The wet strength was measured after an immersion time of 15 sec. The web strength was tested on a 1 inch (2.5 cm)×8 inch (20 cm) strip. The tests were run at 5 inch (12.5 cm) original separation at a cross-head speed of 12 inch (30 cm) per minute. The strength is reported in units of lb./inch (kg/cm).
[0032] The basis weight was measured according to TAPPI test method T 410 om-93, and reported in g/m 2 .
EXAMPLE 1
[0033] An extensible bicomponent fiber comprising a core of a thermoplastic elastomer (DSM type EM400, melting point 195° C.) and a sheath of linear low density polyethylene (Dow Chemical Company ASPUN 34, melting point 128° C.) with a core:sheath weight ratio of 65:35 was prepared using the method described in U.S. Pat. No. 5,505,899. The fiber had a denier per filament (dpf) of 4.6 (5.1 dtex) and was cut to a 2 inch (5 cm) length.
EXAMPLE 2
[0034] A second extensible bicomponent fiber was prepared in the same manner as Example 1. In this example the sheath polymer was an amorphous copolyester (broad melting range around 110° C.), and the fiber had a dpf of 4.8 (5.3 dtex) and was cut to a 2″ (5 cm) length.
EXAMPLE 3
[0035] A third extensible bicomponent fiber was prepared in the same manner as Example 1. In this case the polyethylene sheath (melting point 128° C.) was grafted with maleic anhydride (MAH) by melt blending 10 weight % of Dow ASPUN 07 with the ASPUN 34. The dpf was 4.3 (4.7 dtex) and the cut length was ½ inch (12.25 cm).
EXAMPLE 4
[0036] A fourth extensible bicomponent fiber was prepared in the same manner as Example 3 to give a dpf of 4.6 (5.1 dtex) and was cut to ¼ inch (0.635 cm).
EXAMPLE 5
[0037] Carded webs were prepared with 40% standard round cross section polyester staple fiber having a dpf of 3 (3.3 dtex) and a cut length of 1.5 inch (3.75 cm) (INVISTA type 224) and 60% by weight of bicomponent fibers. These include the extensible bicomponent fibers of Examples 1 and 2, and a commercially available bicomponent binder fiber: INVISTA Type 256 which is a 3 dpf (3.3 dtex), 1.5 inch (3.75 cm) cut fiber having the same polyethylene sheath as Example 1 and a polyester core in a core:sheath weight ratio of 50:50.
[0038] The carded webs were bonded in an oven at 135° C. for 10 seconds. The webs were cycled between zero and 96% elongation for three cycles, and the total load (lb.) (kg) measured at this 96% elongation on each cycle. The results are set forth in Table 1.
[0000] TABLE 1 Load Bicomponent Basis Load after 1 st Load after 2 nd after 3 rd Fiber type weight g/m 2 cycle lb. (kg) cycle lb. (kg) cycle lb. (kg) T-256 98 9.69 (4.4) 1.75 (0.8) 0.79 (0.36) Example 2 116 3.39 (1.54) 0.5 (0.23) 0.3 (0.14) Example 1 95 2 (0.91) 1.97 (0.86) 1.95 (0.89)
This example illustrates that a carded web containing 60% of the extensible fiber with a polyethylene sheath retained its strength after being stretch approximately 100%, whereas the other bicomponent binder fibers lose over 90% of their strength. It is believed from microscopic examination of webs that the copolyester sheath of the extensible bicomponent fiber of Example 2 did not flow sufficiently to expose the elastic core. The extensible bicomponent of Example 1 will have value in nonwoven articles requiring elastic recovery in addition to extensibility, such as, for example, bonded batts and cushions.
EXAMPLE 6
[0039] Wet laid nonwoven webs were prepared with a mixture of bicomponent fibers at a 30 weight % level with wood pulp (Rayonnier Rayocel HF). The extensible bicomponent prepared in Example 3 was used in conjunction with INVISTA Type 105 uncrimped bicomponent 1.5 dpf (1.65 dtex), ¼ inch (0.635 cm) fiber which has the same grafted polyethylene sheath as the Example 3 and a polyester core in a 50:50 weight ratio. The webs were bonded at 175° C. for 30 seconds. The basis weight of the nonwoven webs was 60-65 g/m 2 . The dry and wet web strengths are set forth in Table 2.
[0000] TABLE 2 Bicomponent blend Dry Wet level, % Strength, Strength, Example 3 T-105 lb./in.(kg./cm.) Elongation, % lb./in.(kg./cm.) Elongation, % 0 30 3.25(0.58) 17 1.9(0.34) 13 10 20 2.9(0.52) 19 2(0.36) 18 15 15 2.1(0.37) 21 1.6(0.29) 22 20 10 1.5(0.27) 24 0.8(0.14) 23 30 0 0.9(0.16) 39 0.5(0.09) 44
The use of the extensible bicomponent fiber increases the elongation of the web. This is an important attribute for nonwovens such as wipes, in which a softer hand and the ability to deform the wipe is important. This more extensible web has value as the absorbent core in diapers and feminine hygiene products since it allows the absorbent, especially SAP, to swell to its full capacity.
EXAMPLE 7
[0040] In this example air laid webs were prepared from a blend of bicomponent fibers with 70 weight % wood pulp (Weyco NF401 fluff pulp). The extensible bicomponent fiber of Example 4 was used, together with a commercial 2 dpf (2.2 dtex), ¼ inch (0.635 cm) crimped bicomponent fiber having the same MAH grafted polyethylene sheath as Example 4 and a polyester core in a 50:50 weight ratio (INVISTA T-255). In addition a 3-layer nonwoven web was prepared. The basis weight was 57-60 g/m2 and the webs were bonded at 175° C. for 7 seconds. The dry and wet web strengths for the homogeneous blends are set forth in Table 3, and those for the layer structure in Table 4.
[0000]
TABLE 3
Bicomponent blend
Dry
Wet
level, %
Strength,
Strength,
Example 4
T-255
lb./in.(kg./cm.)
Elongation, %
lb./in.(kg./cm.)
Elongation, %
0
30
2(0.36)
27
1.2(0.22)
26
10
20
1.9(0.34)
31
1(0.18)
30
20
10
1.2(0.22)
36
0.8(0.14)
38
30
0
0.6(0.11)
37
0.4(0.07)
38
The increase in elongation in the air laid nonwoven web is comparable to that seen in Example 6.
[0041]
[0000]
TABLE 4
Top
Bottom
Layer
Middle Layer
layer
Dry
Wet
Ex.
T-
Wood
T-
Ex.
T-
Str.
Str.
4, %
255, %
pulp, %
255, %
4, %
255, %
lb./in.(kg./cm.)
Elong. %
lb./in.(kg./cm.)
Elong. %
10
—
70
10
10
—
1.6(0.29)
37
0.7(0.13)
45
5
10
70
—
5
10
2.2(0.39)
30
2.2(0.39)
36
10
5
70
—
10
5
1.4(0.25)
35
1.35(0.24)
39
The inclusion of the extensible fiber gives a tougher more extensible nonwoven web.
[0042] Thus it is apparent that there has been provided, in accordance with the invention, an article that fully satisfied the objects, aims and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and broad scope of the appended claims. | The present invention relates to a bonded nonwoven having extensive fibers for use in articles such as diapers and other hygienic articles, wipes, interlinings and other articles requiring some degree of elasticity. Specifically it relates to bicomponent fibers where one component is an elastic thermoplastic and another component employed as a binder having a lower melting point than the elastic component. On bonding the binder melts to form bonding points exposing the elastic core. The present invention contemplates a bonded nonwoven article or a component thereof, comprising a blend of extensible bicomponent fibers, an absorbent, and optionally low melt binder fibers, or synthetic fibers, or both. The present invention also contemplates a method of producing a nonwoven by mixing the fibers described above, either by the dry laid or wet laid process, and heating the mixture to bond the fibers into a nonwoven article or a component thereof. | 3 |
BACKGROUND OF THE INVENTION
The invention relates to a rock drill for rotary and/or percussion stress, in particular for percussion or hammer drilling machines.
The production of feed spirals on rock drills usually takes place by milling or whirling. Special forging processes for the production of the drill have also become known. In the case of all processes, the single or double thread feed spiral runs uniformly around the drill shank to the drill head, the spiral pitch being variable, if appropriate, over the length of the feed spiral.
It has become known from German Patent Specification 2,013,327 to design the feed spiral not smooth but staircase-shaped in order to prevent the drilling dust present in the feed spiral slipping due to feed sections with a slight pitch on the feed spiral. In this case, during percussion drilling, the combined rotary and axial movement of the drilling tool is utilised, the drilling tool spinning underneath the drilling dust after axial movement and the associated raising of the said dust, and the raised particles dropping onto the next higher staircase section. The intention of this is to achieve an improved feed without a tendency to clog, it being possible to increase the pitch angle and thus the feed rate.
SUMMARY OF THE INVENTION
The invention is based on the object of creating a drilling tool, in particular a rock drill for use in percussion or hammer drilling machines, in which the feed spiral can be produced easily due to its design and which produces better results in its feed rate than conventionally designed drilling tools.
Starting from a rock drill of the type referred to at the beginning, this object is achieved according to the invention by the provision of a drill spiral having first and second sections offset by 90° in the direction of rotation of the drill, the first sections having a pitch of zero degrees and the second sections having a pitch which is greater than zero degrees.
The rock drill according to the invention is based on the realisation that it is not necessary for a satisfactory drilling dust feed to design the complete feed spiral staircase-shaped or step-shaped with feed sections of flatter pitch. Rather, it suffices if the drilling dust is loosened from time to time along its path over the feed spiral by a rather stronger axial percussive component, in order that a caking of the drilling dust and thus a tendency to clog is avoided. For this purpose, the invention proposes that the feed spiral includes alternately following horizontal feed sections with a 0° pitch and lead sections, the sections in each case encompassing a 90° angle of rotation. Along a lead or pitch, therefore, a first horizontal feed section is followed by a first rising feed section, which is adjoined by a second horizontal feed section and this in turn is adjoined by a second rising feed section. Therefore, with an angle of rotation of 360°, two horizontal and two rising feed sections are provided with one pitch of the spiral. In this arrangement, the horizontal feed sections serve for the loosening brought about by an axial acceleration and the rising feed sections serve for the drilling dust feed itself.
If a feed spiral is divided up into feed sections alternating in this way, this gives rise to a further feature essential for the invention that the feed spiral does not have any undercuts in side view on the horizontal feed sections. This makes it possible to produce the feed spiral in a simple procedure by forging, in particular drop forging with a two-part forging die. The two-part forging die is designed as a ram-shaped die and the forging operation can take place without a rotational movement of the feed spiral. This is preferably achieved whenever the surface tangents of the horizontal feed section run perpendicular to the vertical plane through the horizontal feed section, i.e. whenever there are no undercuts in this feed section. As a result, an extremely inexpensive production process is obtained, even for heavy, solid drilling tools for use in heavy-duty hammer drilling machines.
Consequently, what is decisive for easy production of the feed spiral from a forged base material is the geometrical shape with straight feed sections without undercuts.
The design of the rock drill according to the invention with a double thread feed spiral is particularly advantageous, the horizontal feed sections which are opposite in each case, being formed by horizontal ring segments. The ring segments themselves serve for good guidance of the drilling tool in the drilling hole, since an optimum lateral support of the drill is ensured by the ring segments over the entire drilling length. The ring segments are interrupted by the flanks, in each case obliquely rising, of the rising feed sections.
It goes without saying that the invention may also take the form of a single thread feed spiral. A double threaded feed spiral is advantageous in the case of a drilling tool with a step drill head with center point (holing-through drill), due to the double drilling dust discharge at the drill head.
In an advantageous embodiment as a holing-through drill, the rock drill according to the invention is therefore equipped with a double thread feed spiral with a correspondingly designed drill head. Since such a drill head is itself generally designed as circular-cylindrical with a center point on top and metal carbide cutting elements arranged at the sides, this drill head is joined by two semicircular incisions to the double thread feed spiral.
In a special embodiment of the invention, the rising feed sections may be provided additionally with staircase-shaped flanks, as described in the patent referred to at the beginning.
Further details essential for the invention are described in the following description with reference to an exemplary embodiment.
BRIEF DESCRIPTION OF
THE DRAWINGS
FIG. 1 shows a perspective view of a rock drill according to the invention,
FIG. 2 shows a side view of the ring segment-like horizontal feed sections with rising feed sections in between,
FIG. 3 shows a side view of the representation according to FIG. 2, and
FIG. 4 shows a diagrammatic representation of the feed sections.
DETAILED DESCRIPTION
OF THE PREFERRED EMBODIMENT
The rock drill 1 represented in FIG. 1 is designed as a holing-through drill with a correspondingly designed drill head 2 with a center point 3 and metal carbide cutting elements 4. The double thread feed spiral 5 is joined by semicircular incisions 6 as drilling dust groove to the drill head 2. The drill shank 7 adjoins in the lower region of the drill spiral 5.
As revealed by FIG. 1 in perspective view and by FIGS. 2 and 3 in the respective side view, the feed spiral 5 consists of alternating horizontal feed sections 8,8' with a 0° pitch and feed sections 9,9' which are designed as rising feed sections, individual feed sections adjoining one another at an angle of rotation of 90°. The pitch α of the rising feed sections is denoted by α, where α=20°-60°, and is preferably 45°. In this arrangement, the first spiral has the feed sections 8,9 and the second feed spiral has the feed sections 8',9'. Each helical feed spiral consequently has within a pitch h two horizontally running feed sections 8 and 8' and two rising feed sections 9 and 9' in between.
The feed spiral of the drill according to the invention is also characterised by the feed spiral having no undercuts in the horizontal feed sections 8. To describe this situation, the first vertical plane 11 running parallel to the plane of the page in FIG. 2 and through the longitudinal axis 10 of the drill, or a second vertical plane 12 perpendicular to the first and likewise running through the longitudinal axis 10 of the drill is used. The first vertical plane 11 is perpendicular to the plane of the page in FIG. 3, passes through the longitudinal axis 10 of the drill and halves the horizontal feed section 8,8'. These two vertical planes 11, 12 are likewise drawn in diagrammatically in FIG. 1.
Each horizontal feed section 8 or 8' is halved by the first vertical plane 11 (see FIG. 3) and each surface tangent in the drilling dust groove of the horizontal feed section 8 or 8' is in each case perpendicular to the first vertical plane 11 and to the second vertical plane 12. In the representation of the feed spiral according to FIG. 2, consequently the horizontal feed sections 8,8' can be produced with a two-part forging die which runs perpendicular to the plane of the page. This is a consequence of the horizontal feed section 8,8', including the arcuate transitions 13 between the individual feed sections 8,8' having no undercuts.
As indicated in FIG. 2 in the upper region, in the case of a double thread feed spiral, two laterally opposite horizontal feed sections 8,8' are in each case formed by horizontal ring disk-shaped segments 14, which are interrupted in each case by a rising feed section 9,9'.
In the case of the rising feed sections 9,9' as well, all surface tangents may run parallel to the first vertical plane 11; however, in terms of tool engineering, this is not absolutely necessary in forging, i.e. these feed sections may also be of profiled design. With respect to the second vertical plane 12, the surface tangents run at the angle of rise of the rising feed spiral section 9 and 9'.
In a preferred embodiment, the rising feed sections 9 and 9' may have a staircase-shaped course 15, as mentioned in the patent described at the beginning. As a result, the loosening of the drilling dust is brought about by a vertical impact component also on the rising feed section in addition to the horizontal feed section.
In FIG. 4, the operating principle of the rock drill according to the invention is represented diagrammatically.
The drilling dust generated in the drilling hole passes via the two incisions 6 and 6' via the first rising feed section 9 (9' concealed in FIG. 1) to the first horizontal feed sections 8 and 8', respectively. In these horizontal feed sections 8, 8', as represented in FIG. 4 as a vertical line 16, no feed takes place during an angle of rotation of 90° but only a loosening of the drilling dust due to the vertical percussive movements of the drill. Once the drilling dust has covered an angle of rotation of 90°, it comes to rest in the rising feed sections 9 or 9' and is transported along this feed flank in the direction of the drill shank 7. This axial feeding operation is identified in FIG. 4 by reference numeral 17. After a further transport of the drilling dust over an angle of rotation of 90°, the rising feed section 9,9' is followed in turn by a horizontal feed section 8,8' with a 0° pitch for the loosening of the drilling dust over a transport angle of 90°. Thereafter there finally follows a rising feed section 9,9' with a corresponding feeding operation. The diagrammatic course represented in FIG. 4 over the feed sections 8, 8' is consequently followed over a lead or pitch h. In FIG. 4, the pitch h is represented on an enlarged scale in comparison with the representation in FIGS. 1 to 3. The angles of 90° indicated in FIG. 4 relate to a rotational movement or a transporting movement of the drilling dust along the feed sections by an angle of rotation of 90°.
The invention is not restricted to the exemplary embodiment described and represented. Rather, it also comprises all further developments and refinements accomplished by a person skilled in the art without inventive content of their own. | A rock drill for rotary and/or percussive stress, in particular for use in percussion or hammer drilling machines, is proposed, which by its geometrical design makes improved efficiency and simplified production possible. For this purpose, the feed spiral 5 is designed alternately with horizontal feed sections 8,8' with a 0° pitch, and adjoining lead sections 9,9', the respective feed sections assuming an angle of rotation of 90° on the drilling tool. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a hemostatic clip applier, and, more particularly, to a pistol-type applier having an elongated tubular jaw assembly able to reach areas inaccessible to conventional forcep-type instruments.
In the course of a surgical operation, it is usually necessary to sever blood vessels which must be quickly clamped or ligated to prevent excessive bleeding which could interfere with the operation and pose unnecessary risks to the patient. While major blood vessels are temporarily clamped and later rejoined when the wound is closed, many severed vessels of the vascular system are permanently closed either because other vessels are available to serve their function, or because that portion of the anatomy being served by the vessel has been surgically removed.
Severed vessels are conventionally closed by either tying with ligatures or clamping with ligating clips. Ligating clips are often preferred, especially for permanent closure because of the ease and speed of placement, and the security of the closure. Clips are conventionally applied by means of a forceps-type applier as described, for example, in U.S. Pat. No. 3,439,522. These appliers work well in most general procedures where the severed vessel is accessible to the instrument. In certain procedures, however, particularly in otologic surgery or neurosurgery, a relatively small hole is made in the skull in order to reach and clip off certain blood or other vessels therein, and the small hole does not admit to the use of the forceps-type applier. In thoracic surgery, fluid ducts deep within the chest cavity are difficult to reach with a forceps-type instrument without disturbing other organs. For these and other specific applications, the surgeon may use a special applier having a long, slender nose such as that described in U.S. Pat. Nos. 3,518,993 or 3,777,538.
The long-nose surgical clip applicators of the prior art have certain disadvantages which are overcome by means of the present invention. In prior art applicators, the angle of the jaws holding the clip are fixed relative to the handles of the instrument so that the entire instrument must be maneuvered to align the clip with the vessel. Moreover, the length of the jaw assemblies of the prior art appliers are either permanently mounted or not readily changed so that the surgeon may often be forced to use a longer and more awkward instrument than necessary.
It is accordingly an object of the present invention to overcome the above and other disadvantages of the prior art instruments by providing a long-nose surgical clip applicator having a fully rotatable jaw member. It is a further object of this invention to provide a ligating clip applier with readily interchangeable jaw members of various lengths, and with jaws set at various angles to the main axis of the instrument. These and other objects of the present invention will be apparent from the ensuing description and claims.
SUMMARY
The surgical clip applier of the present invention comprises a stationary handle member and a movable trigger member pivotally connected thereto, and an elongated tubular jaw assembly comprising tube and rod members rotatably secured to the stationary handle member and having opposing jaws on the distal ends thereof. The tube member is engaged by the upper extremity of the trigger member by means of which the tube member and jaw on the distal end thereof are made to reciprocate in an axial direction. The rod member extends through and is slidable within the tube member. The proximal end of the rod member is rotatably but axially fixed to the stationary handle member so that as the tube member is reciprocated by the action of the trigger member, the rod member is stationary and the jaws at the distal ends of the tube and rod members are made to open and close. Sliding guide means between the tube and rod members are provided in the vicinity of the jaws to maintain the jaws in constant alignment during rotation and opening and closing. A knurled ring secured to the tube member is effectively engaged by a yoke at the upper extremity of the trigger member and provides a convenient means for rotating the tubular jaw assembly in order to orient the position of the jaws.
The trigger member of the applier is biased away from the stationary handle member by spring means which causes the jaws of the applier to be maintained in a normally open 30 position. The spacing between the fully open jaws is adjusted to receive and hold a ligating clip. With the clip in position, the nose of the instrument may be inserted into the surgical field and the jaws rotated to any desired angle relative to the handles of the instrument. When the clip is in position over the vessel to be ligated, the trigger member is squeezed toward the stationary handle member thereby closing the jaws and setting the clip on the the vessel. Relaxing the force on the trigger member allows the jaws to open and the instrument to be withdrawn for reloading with another clip.
The tubular jaw assembly is mounted to the stationary handle member by quick release catches which allow jaw assemblies of different lengths to be easily exchanged with no secondary adjustment to the instrument. The jaw assemblies may be provided in any desirable length, and the jaws at the distal end thereof may be set at right angles to the axis of the tubular jaw assembly or slanted forward or rearward by up to about 20 degrees.
DESCRIPTION OF DRAWINGS
FIG. 1 is a view in perspective from the right forward quadrant of a surgical clip applicator in accordance with the present invention.
FIG. 2 is an exploded, partial view in perspective from the left rearward quadrant of the instrument of FIG. 1 showing the barrel mounting and latching means.
FIG. 3 is a left plan view of the trigger member of the instrument of FIG. 1.
FIG. 4 is a left plan view of the stationary handle member of the instrument of FIG. 1.
FIG. 5 is a foreshortened left plan view in partial cross section of the rearward facing jaw and rod assembly of the instrument of FIG. 1 with the jaw detail enlarged.
FIG. 6 is a foreshortened left plan view in partial cross section of the forward facing jaw and tube assembly of the instrument of FIG. 1 with the jaw detail enlarged.
FIG. 7 is an enlarged end view of the forward facing jaw and tube assembly of FIG. 6.
FIG. 8 is a partial sectional view of the jaw assembly of the instrument of FIG. 1 with a surgical clip engaged therein.
FIG. 9 is a plan view of the jaw assembly of an instrument of the present invention wherein the jaws are slanted forward with a surgical clip engaged therein.
FIG. 10 is a plan view of the jaw assembly of an instrument of the present invention wherein the jaws are slanted rearward with a surgical clip engaged therein.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIG. 1, there is shown a pistol-grip-type surgical clip applicator of the present invention comprising stationary handle member 11 including horizontal tubular jaw mounting section 12 at the upper end thereof, trigger member 13 pivotally mounted to said handle member at said tubular jaw mounting section, and tubular jaw assembly 10 mounted on said tubular jaw mounting section and comprising tube 14 terminating in forward facing jaw 15 at the distal end thereof and rod 16 extending through said tube 14 and terminating in rearward facing jaw 17 at the distal end thereof.
Tubular jaw mounting section 12 includes a pair of spaced-apart cradles 18 and 19 and an intermediate box member 20 adapted to receive the upper extremity of trigger member 13. Trigger member 13 is pivotally mounted by pin 21 to said tubular jaw mounting section 12 with the upper extremity of said trigger member extending within box member 20. The upper extremity of trigger member 13 terminates in yoke 22 which is adapted to engage ring 23 secured to tube 14 at a position approximately centered over box 20 and intermediate cradle members 18 and 19. The lower extremity of trigger member 13 is biased away from handle member 11 by cooperating leaf springs 25 and 26.
Tube 14 is slidably and rotatably mounted in saddles 18 and 19 of barrel mounting section 12 by means best illustrated in FIG. 2. Tubular jaw retainers 27 and 28 are secured to box 20 of tubular jaw mounting section 12 by means of thumb screw 29 which extends through drill hole 46 in one wall of box 20 and is secured in tapped hole 47 in the opposing wall of box 20. Retainers 27 and 28 are provided with slot openings 31 and 32 respectively to receive thumb screw 29 and allow for lateral displacement of the retainers. Retainers 27 and 28 are additionally provided with inverted, U-shaped sections 33 and 34 having an effective open width slightly larger than the outside diameter of tube 14.
Tube jaw assembly 10 is mounted to stationary handle 11 as illustrated in FIG. 1 by positioning tube 14 in V-shaped grooves 35 and 36 of saddles 18 and 19, and positioning the U-shaped sections of retainers 27 and 28 over tube 14. When the retainers are in position, inward facing open slots 37 and 38 of retainers 27 and 28 are aligned with pins 39 and 40 extending from saddles 18 and 19 as illustrated in FIG. 1, and the retainers are locked in position by moving the retainers so that pins 39 and 40 are engaged by slots 37 and 38. The retainers are thereafter secured against further movement by tightening thumb screw 29. Retainers 27 and 28 are offset at 41 and 42 to accommodate the width of box 20 and allow both legs of U-shaped sections 33 and 34 to fit closely against the walls of saddles 18 and 19.
Also illustrated in FIG. 2 is rod retaining bracket 43 having vertical open slot 44 adapted to engage a corresponding circumferential groove in the proximal end of rod 16 when the assembly of rod 16 and tube 14 is mounted on saddles 18 and 19. Bracket 43 is permanently secured to the end of saddle 19 by screw 45. Drill hole 30 further illustrated in FIG. 2 receives trigger pivot pin 21 in a press fit. A corresponding drill hole in the opposite wall of box 20 is visible in FIG. 1.
FIGS. 3 and 4 are detailed views of trigger member 13 and handle member 11 respectively. In FIG. 3, trigger member 13 is shaped for comfortable grasping by the fingers of the surgeon. At the upper extremity of trigger member 13 is yoke 22 and pivot hole 46. Leaf spring 25 is secured to the lower extremity of trigger member 13 by means of screw 47 and drilled and tapped hole 48. The free end of leaf spring 49 is slotted to provide a tongue and groove engagement with free end 50 of cooperating leaf spring 26 as illustrated in FIG. 1.
Referring now to FIG. 4, stationary handle member 11 has drilled and tapped hole 52 at the lower extremity thereof whereby leaf spring 26 is secured to handle member 11 by means of screw 51. Handle 11 is shaped to comfortably fit the heel of the hand of the surgeon, and projection 53 defines the upper limit of the grasping area of the handle.
Integral with the upper portion of handle 11 is tubular jaw mounting section 12 which is illustrated in detail in FIG. 4, and includes, in addition to the features already described, set screws 54 and 55 which are threaded through drilled and tapped holes 56 and 57 in saddles 18 and 19, and extend into the interior of box 20. The set screws function to limit the travel of yoke 22 of trigger member 13 in both directions to control the travel of jaw 15 when opening and closing as explained hereinafter. Drill holes 56 and 57 are countersunk at 58 and 59 to provide access to the heads of set screws 54 and 55.
FIG. 5 illustrates rod member 16 partially sectioned at the distal end to show the construction of jaw 17. Rod 16 is slotted at the distal end to receive horizontal extension 60 of jaw 17 in a tongue and groove relationship. Jaw 17 is secured in the slot of rod 16 by means of pin 61. Rod 16 is keyed to tube 14 by means of flange 62 which extends from the horizontal extension of jaw 17 and, in cooperation with the structure of barrel 14 as hereinafter described, functions to maintain jaw alignment during rotation of the jaw assembly and when opening or closing the jaw.
The proximal end of rod 16 includes circumferential groove 64 which cooperates with slot 44 of bracket 43 illustrated in FIG. 2 to prevent axial movement of rod 16 while permitting free rotation when the tubular jaw assembly is mounted on the instrument as shown in FIG. 1.
Referring now to FIG. 6, there is shown a partially sectioned and foreshortened view of tube 14. On the distal end of tube 14 is mounted outward facing jaw 15 which includes at its base cylindrical section 67 circumscribing tube 14 and permanently secured thereto. Tube 14 is slotted at 66 to accommodate flange 62 of jaw 17 illustrated in FIG. 5, and cylinder 67 is provided with slotted flange guard 68 to enclose flange 62 of jaw 17 in the complete tubular jaw assembly as illustrated in FIG. 8.
Referring further to FIGS. 5 and 6, jaws 15 and 17 are provided with grooves 65 and 63 respectively on the faces thereof to receive and hold a single surgical clip as best illustrated in FIG. 8. Grooves 63 and 65 preferably contain serrations on the distal ends thereof as illustrated in the enlarged views of FIGS. 5 and 6 to enhance the ability of the jaws to grip and hold the clip during manipulation of the instrument and closure of the clip over the vessel being ligated.
The construction of jaw 15 will be more fully understood by reference to FIG. 7 where tube 14 and jaw 15 are shown in end view. Flange guard 68 is an extension of cylinder 67, and contains slot 69 having a width and depth corresponding to the width and depth of flange 62. Tube 14 includes slot 66 aligned with slot 69 and extending a short distance beyond cylinder 67 to accommodate the full travel of flange 62. It should be noted that flange guard 68 is a desirable, but not essential feature of the present invention and might be eliminated for certain applications where it is desirable to reduce the overall diameter of the distal tip of the clip applicator.
Returning now to FIG. 6, ring 23 is secured to tube 14 intermediate saddles 18 and 19 and at a point approximately centered over box 20 when the tubular jaw assembly is mounted on the instrument as illustrated in FIG. 1. Ring 23 is preferably knurled on the outer surface 70 thereof to facilitate rotation of the tube in the assembled instrument.
FIG. 8 illustrates the detail of the tubular jaw assembly comprising rod 16 inserted within tube 14 with jaws 15 and 17 in alignment and with clip 71 retained between the jaws in grooves 63 and 65.
The operation of the surgical clip applier of FIG. 1 is generally as follows: a tube and rod jaw assembly is selected and mounted to the stationary handle member of the instrument as aforedescribed to obtain the instrument as illustrated in FIG. 1. The trigger member biasing springs cause the yoke of the trigger member to urge ring 23 and tubular member 14 in a rearward direction, thereby opening the jaws of the instrument. Set screw 54 is adjusted to obtain the appropriate spacing between jaws 15 and 17 to accommodate clip 71 with a friction fit. The mounted tubular jaw assembly may be freely rotated about 360 degrees by means of knurled ring 23. Flange 62 of jaw 17 in cooperation with slot 66 of tube 14 serves to maintain the jaws in alignment as tube 14 is rotated.
After the jaw assembly has been rotated to place the jaws at the desired angle, the instrument is manipulated to place the clip over the vessel to be ligated, and the trigger member is squeezed to close the jaws and set the clip. As the trigger is urged toward the stationary handle member against the bias of the springs, the yoke of the trigger member urges ring 23 and barrel 14 forward, thereby closing jaw 15 against jaw 17. Rod 16 is restrained against axial travel by circumferential groove 64 cooperating with slot 44 of bracket 43, and jaw 17 accordingly remains stationary as jaw 15 closes toward it.
The forward travel of jaw 15 is limited by set screw 55 abutting yoke 22, and set screw 55 is adjusted before use to provide for complete clip closure without placing unnecessary stress on the jaws of the instrument. After the clip has been set, the pressure on the trigger member is relaxed allowing the biasing springs to move the trigger member forward, thereby opening the jaws of the instrument by moving tubular member 14 and jaw 15 in a rearward direction while jaw 17 remains stationary.
Once set screws 54 and 55 have been adjusted for a given clip, other tubular jaw assemblies of longer or shorter lengths may be mounted on the handle member with no readjustment of the instrument being required for the same 30 size clip. In the event a larger or smaller clip is to be applied, readjustment of the set screws to obtain the appropriate jaw spacing for the new clip may be required.
The rotational freedom of jaw assembly 10 on saddles 18 and 19 is controlled by frictional engagement with nylon-tipped set screw 73 which projects from drill hole 72 into V-shaped groove 35 of saddle 18 as illustrated in FIG. 4. After the jaw assembly is mounted on saddles 18 and 19 and retainers 27 and 28 have been secured as aforedescribed, set screw 73 is adjusted so that the nylon tip abuts the wall of tube 14. Set screw 73 is thereupon tightened until the frictional engagement with tube 14 is sufficient to secure the jaw assembly in any desired position while permitting the intentional rotation thereof with minimal effort.
For certain surgical procedures, it may be desirable to angle the jaws in a forward or rearward direction as illustrated in FIGS. 9 and 10. The jaws may be angled up to about 20 degrees or more from the vertical and still operate in a satisfactory manner. Clips set from angled jaws tend to roll during closure with the result that the legs of the clip are of unequal lengths when closed, but this has no practical consequence in terms of efficacy or performance. Jaws 15 and 17 may be slanted forward or rearward up to about 45 degrees or even more with the understanding that the greater the slant, the greater the roll imparted to the clip during closure.
The preceding description has been directed toward a preferred embodiment of the present invention as illustrated in FIG. 1. Many variations in design and construction will be apparent to those skilled in the art, and are included within the scope of the present invention. For example, the cooperating leaf springs of the handle of the instrument may be replaced by any other means effective to bias the trigger member away from the stationary handle member so that the jaws of the instrument are in a normally open position. In addition, a variety of mechanisms are available for mounting the tubular jaw assembly onto the handle member, the only requirement being that the tubular member is free to rotate with sufficient axial movement to permit the jaws to open and close. Likewise, the rod member of the applier may be mounted in any manner which allows the rod to rotate freely without axial movement.
In other embodiments, jaw 17 may be secured to rod 16 by a pin as shown or may be welded or silver-soldered in place. Likewise, jaw 15 may be secured to tube 14 by any convenient means. The cooperating flange and slot assembly of jaws 15 and 17 may be replaced by any other guide means effective to maintain the jaws in alignment during rotation and closure. | A pistol-type surgical instrument for applying ligating clips to blood vessels and other tubular ducts in remote locations which are substantially inaccessible to conventional forceps-type appliers. Tubular jaw assemblies of various lengths may be mounted on the pistol-grip handle of the instrument, and the mounted jaw assembly is fully rotatable to permit orientation of the clip applying jaws. The jaws are preferably at right angles to the axis of the tubular jaw assembly, but may be slanted forward or rearward up to about 20 degrees. | 0 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This application claims priority to and is a division of U.S. application Ser. No. 11/409,384 filed Apr. 20, 2006, now issued on Apr. 22, 2008 as U.S. Pat.No. 7,361,281, incorporated herein by reference in its entirety; which application claims priority to and is a division of U.S. application Ser. No. 11/085,961, filed Mar. 21, 2005, and now issued on May 9, 2006 as U.S. Pat. No. 7,041,223 incorporated herein by reference in its entirety; which application claims priority to and is a division of U.S. application Ser. No. 10/001,185, filed Oct. 25, 2001, and now issued on Apr. 12, 2005 as U.S. Pat. No. 6,878,286 incorporated herein by reference in its entirety; which is an application claiming the benefit under 35 USC 119(e) U.S. application Ser. No. 60/243,647, filed Oct. 25, 2000, incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
This invention relates to ion exchange systems for removing contaminants from water. More particularly it relates to fixed bed ion exchange systems which are configured to yield the flexibility and efficiency of moving bed systems.
BACKGROUND AND STATE OF THE ART
Ion exchange is a chemical process often used to separate certain contaminant substances from a drinking water supply containing a mixture of several other harmless dissolved substances. For example, common ground water used for drinking water will contain substances such as the ionic forms of calcium, magnesium, sulfate, chloride and bicarbonate. In many cases, the water may also contain contaminants that are known to be detrimental to health. Such ionic substances as nitrite, nitrate, arsenic, antimony, fluoride, selenate, chromate, perchlorate and other similar harmful substances are often found. It is desirable to separate out the contaminants harmful to health by treating the water with an ion exchange system. It is also desirable to separate cations such as calcium and magnesium from this mixture if the water is to be used for industrial processes.
Ion exchange processing systems range in production capacity from 50 gallons per day (GPD), such as is used in home water softeners and water purification devices, to very large plants having a capacity of several million gallons per day (50 to 100 million GPD) for centralized treatment of a public water supply.
Various equipment configurations or systems of vessels, plumbing and valves are used to apply the ion exchange process to the above purpose of treating a water supply to remove undesirable substances. For example, one prior art system is shown in FIG. 1 as system 100 . This system is referred to as a single “fixed bed” design. The water to be treated is pumped from line 10 through a vessel 12 containing a bed 14 of ion exchange resin. Purified water is removed via line 16 . Note that the word “single” indicates that all process streams flow through the vessel 12 only once before continuing flow. Also the term “fixed bed” indicates that all ion exchange vessels are fixed in their positions.) During operation, there is no visible change in the positioning of the vessels or piping or any other component, only the internals of the valves change as they go from open to closed. (In contrast, when a moving bed system is in operation the position of the vessels and piping change and a multiport valve remains in a fixed position.
The vessel 12 containing the bed 14 is equipped with about eight to eleven different valves which control which process stream passes through the ion exchange bed. These are large full capacity valves capable of handling 50 to 100 percent of the peak flow-rate through the plant. Practical flows of 500 to 1000 gallons per minute or more capacity for valve passage are not uncommon. By selecting the proper set of valves to be opened or closed either manually or by electronic controls, the flow of water to be treated by being passed through the vessel 12 and resin bed 14 can be stopped when the resin bed is exhausted. Control valve operations allow a sequence of process steps to be executed involving rinsing, regenerating and back washing and declassification (if required) to restore the adsorptive capacity of the resin. This sequence of steps produces a quantity of waste water that contains waste salt materials. This quantity of waste water is discarded. In FIG. 1 regenerant solution, such as brine, is shown supplied via line 18 and removed via line 20 and rinse liquid is shown being supplied via line 22 and removed via line 24 .
Use of a single fixed bed of the prior art is also similar to a batch operation in that the flow of treated water is stopped completely while the resin goes through the resin regeneration steps. If an uninterrupted flow of treated water is desired, at least two fixed bed units must be used in parallel. Each bed is operated as above. After the first bed is exhausted, the bed is taken off line and regenerated while the second bed is placed into operation.
In general, a fixed bed system is comprised of as few vessels as is economically possible from the cost equipment point of view. Keeping the number of vessels to a minimum also reduces the number of large valves to be maintained or replaced. It also simplifies the valve control system with fewer valves to operate. It is customary therefore for plant designers to minimize the number of vessels to keep the number of valves to a minimum.
There are disadvantages, however, because larger vessels and large valves are required. To maintain or replace vessels or valves on a twelve foot diameter vessel, two or three men are required with the aid of heavy equipment lifting devices. Operation and maintenance costs will rise when first equipment costs are low because of large vessels. A popular design of a fixed bed system uses three vessels. Twenty four to thirty three large valves must be operated and maintained on such a system.
With a fixed bed system it is also often required to declassify the resin bed after regeneration. This step requires time and process water and produces additional waste water. The present invention eliminates this step.
Another prior art ion exchange system is known as a moving bed system or as a “merry-go-round” design. In this system the ion exchange resin is contained in several small vessels containing only an inlet port and an outlet port. Multiport valves communicate with these ports and control which process stream flows through each vessel. FIG. 2 depicts such a system as 200 . These systems eliminate the use of large vessels and the subsequent high maintenance and replacement costs. In these systems multiple vessels 12 , such as eighteen vessels numbered 1 through 18 are mounted on a circular platform 26 near the perimeter of a platform that slowly rotates while the system is in operation. The vessels 12 are each coupled through a line 32 to an upper multiport valve 28 and through a line 34 to lower multiport valve 30 . Valves 28 and 30 can be combined or separate as shown.
The multiport valves are constructed with fixed (in and out) ports corresponding in position to the (in and out) ports of the ion exchange vessels which rotate part. The types of process streams flowing through the various vessels is controlled by the multiport valves 26 and 28 and is dependant on the position of the vessel on the circular platform. Consequently, as the platform rotates, the process stream entering and leaving any of the vessels changes according to a predetermined and difficult to alter process flow, set by the multiport valves.
Returning to FIG. 2 , the system 200 shown therein has eighteen discreet vessels 12 and eighteen discreet positions for a vessel on the circular, rotating platform 26 . The rotation of the platform physically moves each vessel from one position to the next position with all eighteen vessels moving simultaneously. The multiport valves 26 and 28 are positioned in the center of the rotating platform. The main process streams of treated water, regenerant, and rinse are first fed to the central multiport valves that then select the appropriate process stream for each position into which a vessel can be placed.
For example, a single vessel physically moves from position to position as shown in FIG. 2 When a given vessel is in positions 4 through 18 on the merry-go-round, it is fed untreated water from line 10 through valve 26 and line 30 which it purifies and discharge via line 32 , valve 28 and line 16 . As the vessel moves from position 4 through to 18 it continues in water treatment service but at each successive step the resin becomes more and more loaded with contaminant until it is virtually exhausted in position 18 . When the vessel is moved into positions 1 through 2 , a brine stream enters the vessel via line 22 , valve 28 and line 32 to regenerate the resin by displacing contaminant off of it. Spent regenerant is removed via line 34 , valve 30 and line 24 . When the vessel is moved into position 3 , a rinse and/or backwash stream enters the vessel via line 18 , valve 30 and line 34 to displace regenerant solution. Rinse is removed via line 32 , valve 28 and line 20 . After making a complete rotation around the merry-go-round the vessel again enters the adsorption section starting at position 4 and advances step by step again to repeat the cycle.
One result of this configuration is the elimination of the large single port valves which were required for the fixed bed design. Practical designs for the moving bed systems incorporate numerous small vessels as dictated by mechanical stability and weight distribution considerations. The most mechanically stable systems use several (ten to forty) small vessels mounted on the “merry-go-round” to obtain an evenly distributed mechanical load.
These conventional systems present the following disadvantages.
High Wastewater Production
Conventional ion exchange systems are usually designed to keep equipment costs and operator and maintenance costs to a minimum while producing a water suitable for consumption. The generation and disposal of wastewater produced by ion exchange systems is usually a less important consideration. Conventional systems will produce from two to ten percent of the plant production as wastewater. The present invention minimizes waste water production and minimizes those operating costs dealing with the production and disposal of waste water. In many cases, the disposal of waste is a major cost of operation and becomes most important when operation over several years is considered. The invention produces as little as ten to thirty percent of the waste produced by conventional designs.
High Valve Maintenance and Spatial Requirements
Another disadvantage of the fixed bed system is the large number of heavy and bulky automatic valves needed to control the process flows through each vessel and the use of large diameter vessels. The main disadvantage of the moving bed system is that it requires two to three times the space and also requires very large and complex specialized multi port valves and a complex plumbing design. The net result is a far more costly system—approximately three times the cost of its fixed bed counterpart.
Mechanical Instability and Cost
Another disadvantage of the moving bed system is its inherent mechanical instability. It presents a high center of gravity on top of a central mounting pivot. This design is subject to relatively small earthquake forces. Steel girder supports are often required to enhance stability, but cost increases.
Design Inflexibility
Disadvantages common to both systems of the art in comparison to the invention are that the process flow design for each conventional system must be fixed, at design time. Fixed mechanical elements will determine the process stream that enters and leaves each vessel. To alter the process design at run time, the valves built into the rotating platform or the multiport valve, which rotates in unison with the rotating platform, must be mechanically altered or completely redesigned. Run time changes in a fixed bed system will also require physical changes to the system such as re-plumbing a portion or all of the vessels and valves.
The present invention allows flexibility in process design and equipment and optimum placement of vessels and piping to maximize process efficiency and minimize wastewater production. It permits any vessel to be out of service at any time. Other advantages are discussed below.
STATEMENT OF THE INVENTION
This invention provides a special water treatment system comprised of a combination of ion exchange vessels, valves, piping and plumbing, electronic controls and processing sensors. This system is more efficient to construct, maintain and operate than conventional systems. The invention combines features of fixed bed systems with those of moving bed systems.
The invention primarily applies to the treatment of water having typical drinking water components such as calcium, magnesium, sodium and chloride ions but also containing undesirable inorganic contaminants such as nitrate, perchlorate, arsenic, antimony, chromium, selenate and/or vanadium ions.
A particular advantage of the invention is its ability to provide treated water with a markedly reduced amount of waste water being produced.
We now have devised a fixed bed system for ion exchange water purification which embodies the advantages of a moving bed system without the size and cost of a moving bed design. The present design involves employing a substantial plurality (at least ten and preferably from about ten to about twenty-five) of fixed bed vessels which do not move but which can be accessed by the various process flows using a series of controller-actuatable valves, for example microprocessor-controlled valves. The system uses closely clustered, fixed position, multiple vessels combined with valves and piping so arranged to obtain the cost advantages of using small mass-produced vessels and valves, and a combination of easily maintained valves.
The present invention achieves (1) high process efficiency, (2) process flexibility, (3) low wastewater production, and (4) construction compactness and maintenance ease.
The invention uses several relatively small diameter fixed vessels each with two ports, one on each opposite end. These ports are closely associated with small volume headers. These headers are connected to manifolds used to conduct the process fluids to and from the vessels. A nest of small, easily-accessible process control valves is mounted between the headers and the manifolds.
Thus, in one aspect this invention is embodied as a system for continuously removing contaminants from contaminated water. This system includes a plurality of immobile vessels, each containing a resin bed capable of binding the contaminants from the contaminated water and yielding purified water and a contaminated resin bed. The vessels each have a first fluid communication opening (port) at a first end and a second fluid communication opening at a second end. The resin bed is located between the two ports.
Each vessel has two headers directly adjacent to the two ports. These headers are connected to the ports with a minimum of dead volume. Each of the headers is directly connected through automatically-actuatable valves to a series of manifolds which supply the various process feeds and accept the various process products.
The actuatable valves are controlled by a controller to flow contaminated water from a manifold through the resin beds in a first subset of the plurality of vessels. This causes these resin beds to remove contaminant from the contaminated water and deposit the contaminant upon the resin in the beds and yield treated water. This treated water is removed from these vessels to a second manifold. The controller sets other valves to simultaneously flow regenerant solution from a manifold through at least one resin bed in a second subset of the plurality of vessels to regenerate its resin bed and to remove spent regenerant solution from these vessels. The controller also directs other valves to flow rinse water from a manifold through at least one regenerated resin bed in a third subset of the plurality of vessels to rinse its regenerated resin bed and to pass spent regenerant and/or used rinse water from the vessels in this third subset.
In another aspect this invention is embodied as a continuous process for purifying water. This process involves the following steps:
Contaminated water is fed through a first manifold to individually-valved first headers each directly adjacent to a first port of a first subset of a plurality of immobile vessels. Each of these vessels contains a resin bed between this first port and a second port. The resin bed is capable of binding contaminant from the contaminated water and yielding treated water and a contaminated resin bed.
Treated water is removed through the second port from each of the vessels in the first subset, and passed through a second individually-valved header directly adjacent to the second port and through a second manifold to a treated water discharge.
Simultaneously, regenerant solution is fed to an individually-valved header directly adjacent to a first or second port on one or more additional vessels making up a second subset of the plurality. Each of the vessels in this second subset contains a contaminated resin bed. The regenerant solution is passed over the contaminated resin bed so that the regenerant displaces the contaminants off of the contaminated resin bed to yield a regenerated resin bed and spent regenerant solution which is removed from the other port on the vessel and through another individually-valved header directly adjacent to this port.
At the same time that the first subset of vessels is removing contaminants and producing purified water, rinse water is fed to an individually-valved header directly adjacent to a first or second port on one or more additional vessels making up a third subset of the plurality. Each of the vessels in this subset contains a resin bed that has been treated with regenerant. The rinse water is passed over the regenerated resin bed to yield a rinsed, regenerated resin bed and used rinse water which is removed from the other port on the vessel and through the individually-valved header directly adjacent to this opening.
In preferred embodiments, the directions of flow of the water regenerant and rinse are specified and the flows of regenerant and rinse are in series through more than one vessel.
DETAILED DESCRIPTION OF THE INVENTION
Brief Description of the Drawings
This invention will be described with reference being made to the accompanying drawings in which:
FIG. 1 is a schematic side cross-sectional view of a typical single fixed bed ion exchange unit of the prior art;
FIG. 2 is a schematic perspective view of a typical multiple moving vessel ion exchange unit of the prior art showing representative process flows;
FIG. 3 is a schematic top view of a multiple fixed vessel ion exchange unit of the present invention;
FIG. 4 is a schematic side partially cross-sectional view of an ion exchange vessel and associated piping for use in the multiple vessel, fixed vessel, water purification systems of the present invention;
FIG. 5 is a schematic side cross-sectional view of an ion exchange vessel similar to that shown in FIG. 4 with a simplified piping scheme. The vessel is set up for use in the multiple vessel, fixed vessel, water purification systems of the present invention with cocurrent treatment and regeneration;
FIG. 6 is a schematic side cross sectional view of an ion exchange vessel similar to that shown in FIG. 5 but set up for countercurrent regenerant flow.
FIG. 7 is a schematic side elevational view of a multiple fixed vessel ion exchange system 700 of the present invention showing representative process flows;
FIG. 8 is a schematic view of a system 800 corresponding to the system of FIG. 7 but adapted specifically for countercurrent regeneration;
FIG. 9 is a schematic cross-sectional view of an ion exchange vessel used in the systems of the invention showing that preferably the ion exchange resin substantially fills the vessel and illustrating representative distributors for assuring a proper fluid flow through the vessel;
FIG. 10 is a detail of FIG. 9 showing fluid flow distributors;
FIG. 11 is a schematic cross-sectional view of two sets of ion exchange vessels, illustrating a regeneration scheme of the prior art and a regeneration scheme in accord with the present invention;
FIG. 12 is a graph comparing regeneration efficiency of the two regeneration schemes illustrated in FIG. 11 ;
FIG. 13 is a block diagram showing the use of an ion exchange system of this invention in an overall process for removing arsenic from waste water.
DESCRIPTION OF PREFERRED EMBODIMENTS
Definitions
Further explanations of the process and systems of this invention use the following terms:
“Bed volume” refers to a volume of fluid passed through a treatment vessel and passed over a bed of resin. A “bed volume” is the volume of an empty vessel and thus need not take into account the volume of resin present in the vessels or the volume of any piping or distributors present within the vessel. Typically, the resin and piping fill about 70% of a bed volume and the head space above the resin and the voids between the resin particles make up about 30% of a bed volume.
“Directly adjacent” and “directly attached” define the relationship between the ports on the ion exchange vessels and the headers associated therewith and set forth that the headers are positioned very close to the ports to minimize fluid hold up volume. These terms have the same meaning when defining the relationship between the headers and the manifolds and between vessels.
“Header” is a zone in a pipe where several other pipes come together.
“Manifold” is a pipe that conducts a process stream from its source to all of the vessels in the ion exchange system.
“Step” refers to a part of the process that is conducted within an ion exchange vessel. The overall process is defined as the sum of all the steps of the process. Many steps may occur simultaneously in the entire group of working vessels, however, any given vessel progresses in an orderly manner through a sequence of steps.
Design Features
The system and method of this invention employ and embody the following design features:
1. A substantial plurality of ion exchange vessels, for example from about ten vessels to about one hundred vessels, are used.
2. Each vessel is equipped with two fluid entry/exit ports, one on either end of the body of resin contained within the vessel.
3. The vessels are located directly adjacent to one another to minimize hold up volume of interconnecting piping.
4. The vessels have headers directly attached to their fluid entry/exit ports.
5. Manifolds are used to conduct the process fluids from a common supply of each fluid to the headers on each vessel.
6. The headers are directly adjacent to their associated manifolds.
7. Individual valves are present in the lines directly coupling each manifold to each header.
8. Any process fluid can enter and flow through any vessel or selected group of vessels at any time under the control of the individual valves and an automated controller.
9. Process fluids can flow through several vessels consecutively (as in series configuration) or simultaneously (as in parallel connection) under the control of the individual valves and the controller.
10. The vessels are filled as full as possible with resin to further minimize hold up volume within the vessels.
The ion exchange systems of this invention employ a substantial plurality of treatment vessels. FIG. 3 depicts one physical arrangement of the multiple vessels in the system 300 of this invention showing eighteen vessels in two rows of nine vessels each. A piping gallery of manifolds can be located between the two rows directly adjacent to the headers on the vessels. A different configuration could consist of one row of eighteen vessels, three rows of six vessels, or the like with directly adjacent manifold galleries. The number of vessels can vary from about ten to about one hundred vessels but typically from about ten to about thirty vessels and particularly ten to twenty-five vessels.
The vessels are stationary and positioned directly adjacent to each other. Fluid access to the individual vessels is controlled by computer-controlled individual valves between the headers and the manifolds to allow any vessel to be in any step of an ion exchange process. These are generally small, single port valves.
In essence, the invention can be described as consisting of numerous fixed bed vessels closely positioned to each other and to process stream manifolds so as to minimize the process stream piping, whose process stream flows are sequentially controlled and integrated to provide a variety of process designs which are not achievable by conventional systems. The invention uses a cluster of small single port valves located between the headers and the manifolds. The invention uses a programmable logic controller program to regulate and sequence the flows through these valves to and from the vessels. This controller opens or closes the individual valves at each individual vessel to control process streams. The operator, by re-programming the controller, can alter these portions of the process.
The relationship of the fluid flows to a typical vessel is shown as system 400 in FIG. 4 . There a vessel 12 is depicted filled with resin bed 14 . Vessel 12 is equipped with two headers, 40 and 42 . These headers are attached to ports located at opposite ends of vessel 12 with resin bed 14 in between them. For the sake of this description, header 40 is shown as the header through which contaminated water is fed and 42 is the header through which treated (purified) water is removed. It will be appreciated that while this downflow mode of operation is most common it is merely representative and that an upflow or side flow configuration could be used if desired. Although not depicted in detail in FIG. 4 the two headers are mounted close to the two fluid access ports on vessel 12 . That means that lines 44 and 46 are generally as short as is practical. This minimizes the hold up volume in the system and thus minimizes the amounts of excess fluids which are likely to end up in waste.
In one embodiment as shown in FIG. 4 , a series of manifolds, 48 , 50 , 52 , 54 56 and 58 , and optionally 59 and 60 , surround vessel 12 . These manifolds are in valved fluid communication with headers 40 and 42 . Manifold 48 distributes untreated water to all of the vessels. Untreated water flows through line 10 and valve 62 , when open, to header 40 and thence through line 44 to vessel 12 . Again, the distance from valve 62 to header 40 should be as small as possible to minimize fluid hold up. Treated water is removed via line 46 to header 42 and thence though valve 64 , when open, and line 16 to manifold 50 for collection and discharge as purified product water. Multiple vessels will be carrying out the same process step with their valves 62 and 64 set to allow the flow of untreated water from manifold 48 to these vessels and the collection and discharge of treated water out through manifold 50 .
When the resin bed 14 becomes contaminated or otherwise loses efficiency and requires regeneration, the flow of untreated water can be halted and a regenerant solution can be fed from manifold 52 through line 18 and valve 66 to header 40 . In one generalized mode of operation, this flow of regenerant will push treated water out of vessel 12 . This water can be passed out through header 42 and manifold 50 . When regenerant breakthrough is about to occur at the base of resin bed 14 , valve 64 can be closed and spent regenerant can be redirected from header 42 through valve 68 and line 20 to manifold 54 for disposal. Once regeneration is complete, the flow of regenerant from manifold 52 can be halted and rinse water, which is typically treated water, can be fed from manifold 56 through line 22 and valve 70 to header 40 . This rinse water flow can initially push out regenerant such as to manifold 54 . Thereafter, the rinse water flow can either be directed through valve 68 to manifold 54 or be routed through line 24 and valve 72 to manifold 58 for disposal or other use.
After a suitable volume of rinse water has been passed over the resin bed to reduce the amount of regenerant in the effluent, this vessel is ready to be reinstalled in service, purifying water.
One of skill will recognize that there are several variations of the flows during regeneration and rinsing. For example, flows can be cocurrent or countercurrent. Flows can move from vessel to vessel, displacing and pushing vessel contents.
System 400 optionally includes one or two or more additional manifolds. These manifolds are referred to as “intermediate manifolds” or “transfer manifolds”. Two such manifolds are shown as manifolds 59 and 60 which are located in lines 74 and 76 , respectively. Line 74 contains valves 78 and 80 and line 76 includes valves 82 and 84 . Lines 74 and 76 each span headers 40 and 42 . These optional manifolds connect to all of the vessels and by opening and closing valves 78 , 80 , 82 and 84 appropriately make it possible to reroute flows from one vessel to another vessel. This rerouting through the intermediate manifolds makes it possible to achieve upflow or downflow operation in individual steps in individual vessels if desired. It also allows parallel flows to be converted into series flows and vice-versa These variations using intermediate manifolds will be described in further detail with reference to the representative overall process flows depicted in FIGS. 7 and 8 .
Turning to FIG. 5 , a second representative vessel configuration, system 500 , is shown. As compared to system 400 , system 500 is somewhat less complicated and uses somewhat fewer parts and for these reasons is generally preferred, particularly for processes which employ downflow purification and cocurrent (downflow) regeneration.
System 500 has many of the features of system 400 shown in FIG. 4 which need not be repeated. System 500 has two intermediate manifolds 59 and 60 , but both are mounted on a common line 75 / 74 / 76 containing valves 78 and 80 and spanning the two headers 40 and 42 on vessel 12 .
System 500 is further simplified by having a manifold 52 which can be used to supply regenerant cocurrent to the water treatment flow.
Spent regenerant is taken off via manifold 54 and transferred via 3 way valve 86 either to regenerant storage via line 88 or to waste via line 90 . Regenerant can also be routed from header 42 , as it leaves column 12 , through valve 80 , through intermediate manifold 59 or 60 to a second vessel where by opening a valve corresponding to valve 78 or valve 80 the regenerant can be flowed over the resin in this second vessel in cocurrent or countercurrent flow. This flow of regenerant through the intermediate manifolds and lines 74 and 75 can also be directed to the regenerant storage via line 92 and valve 94 .
Rinse water, which is treated water, is available in manifold 50 and can be fed via valve 64 upflow into header 42 and thence to column 12 . This rinse can flow out via line 75 to manifold 59 and then to an adjacent vessel or via line 92 and valve 94 to regenerant storage as make up water. Rinse water can also be routed for downflow feed via intermediate manifolds 59 or 60 .
As shown, the intermediate manifolds 59 and 60 can be used to reroute flows from one vessel to another vessel. For example, regenerant solution, particularly when only partially spent, could be passed from a first vessel through intermediate manifold 60 or 59 to an adjacent vessel where it could pass through that second vessel's valve 78 and thence to header 40 and into that second vessel for additional regeneration duty.
In both of the systems 400 and 500 the water flow and regenerant flow are each downflow and the rinse water is either fed to the top or bottom manifold for cocurrent downflow or countercurrent upflow. While one could, in theory, use intermediate manifold 59 or 60 to reroute the regenerant flow to countercurrent (upflow) if such flow was called for, this would not be practical for continuous operation. In this case, it would be more sensible to connect up the feed and product lines to achieve the desired flow direction.
A representative countercurrent (upflow) regeneration system is shown in FIG. 6 as system 600 . In this system regenerant is fed through manifold 54 and valve 68 to lower header 42 . Rinse water is available from manifolds 50 for upflow feed as well. Effluents can be taken off via line 44 and recycled to a second resin bed via line 75 and valve 78 via transfer manifold 59 or 60 , discharged to waste via three way valve 96 and line 98 or sent to the regenerant tank via valve 96 and line 100 .
In typical operation, vessels configured as shown in FIG. 4 , 5 or 6 spend most of their time in service purifying water and a shorter period being regenerated. The flow rate of water being treated also is substantially greater than the rates needed for regeneration and rinse. Accordingly, the manifolds and piping for the water treatment flows can be of larger size than the piping for regenerant and rinse flows. This is a particular advantage of the present invention in that the individual vessels can be treated individually according to different time cycles at different steps by control of the valves feeding and removing flows. With the prior art moving bed designs, all beds moved simultaneously and the times for each step were locked to the bed movement cycle.
A first embodiment of the overall system of the invention is shown in FIG. 7 as system 700 . System 700 includes eighteen vessels 12 - 1 through 12 - 18 , where eighteen is a representative number in the range of ten to twenty-five or greater. Each vessel is numbered with an identifier “ 1 ”, “ 2 ” . . . “ 18 ” to identify its unique position in the overall system. Each vessel is configured for cocurrent flow of treatment water and regenerant essentially as set out in FIG. 5 and is equipped with headers, manifolds, lines and valves as described with reference to FIGS. 4 and 5 . These elements are numbered in accord with the numbering used in FIGS. 4 and 5 with an added indication if a particular element is associated with a particular vessel. For example, header “ 40 - 1 ” is the “ 40 ” header associated with vessel 1 .
Each of the eighteen vessels contains a bed of ion exchange resin and each has a header 40 - 1 , etc which provides access to the vessel and to contaminated water supplied by feed manifold 48 , via valves 62 - 1 etc. In the view shown, valves 62 - 1 through 62 - 15 are shown with a black dot to indicate that contaminated water is feeding through these valves and through the resin beds in vessels 12 - 1 through 12 - 15 . Purified water is being withdrawn from these fifteen vessels through headers 42 - 1 and valve 64 - 1 , etc and collected in manifold 50 for use. Again, valves 64 - 1 through 64 - 15 all are shown with a dot to show a positive fluid flow.
Vessels 12 - 16 through 12 - 18 are not in service purifying water. The resin beds in vessels 12 - 17 and 18 are undergoing regeneration with a brine solution and the bed in vessel 12 - 16 is being rinsed to remove spent brine prior to being returned to service.
In a very straight forward approach, this regeneration could be carried out by passing fresh brine from tank 102 through beds in vessels 12 - 17 and 12 - 18 with the effluent going to waste via line 90 . Rinse water could be fed to vessel 12 - 16 from manifold 50 and this rinse water could also be passed to waste line 90 via intermediate manifolds 59 , 54 and 60 and lines 74 and 76 . This would lead to large volumes of waste, however, and is not preferred. A more efficient process would minimize the volume of waste generated.
In a representative preferred process, vessel 12 - 18 is taken out of service filled with water. Regenerant brine that has already been partially used by being first passed downflow through vessel 12 - 17 is passed through manifold 60 and 59 to the top of vessel 12 - 18 and passed downflow through that vessel. The volume of this flow of brine is generally from at least about ½ a bed volume to about 3 bed volumes and especially from about 1 to about 2 bed volumes. The first about ⅓ bed volumes of regenerant fed to vessel 12 - 18 displaces the water present in the vessel. This volume of water can be sent to product water via manifold 50 or it can be discarded, or it can be sent to the brine tank 102 via manifold 54 valve 86 and line 88 . This last alternative is preferred. The remaining regenerant passing through vessel 12 - 18 at this stage can be recycled to the brine tank together with the water but preferably up to about one bed volume is sent to waste via manifold 54 , valve 86 and line 90 .
The volume of used regenerant fed to vessel 12 - 18 is equal to a volume of fresh regenerant fed to vessel 12 - 17 via line 53 and manifold 52 . Thus, at the completion of this stage of regeneration, vessel 12 - 18 is full of used regenerant and vessel 12 - 17 is full of fresh regenerant.
Controller 104 then reconfigures the valves associated with vessels 12 - 16 , 12 - 17 and 12 - 18 for the next stage of regeneration. In this stage, fresh rinse water is passed from manifold 50 through valve 64 - 16 upflow through vessel 12 - 16 . Vessel 12 - 16 is full of used rinse water previously added as will be described. The fresh rinse water, ½ to about 1 bed volumes and preferably about ⅔ of a bed volumes, pushes used rinse water from vessel 12 - 16 to manifold 52 where it passes through valves 66 - 16 and 66 - 17 and flows downflow into vessel 12 - 17 now pushing the fresh brine previously added to 12 - 17 before it. This about ⅓ bed volumes of fresh brine followed by some amount of rinse water, typically at least about ⅙ bed volumes to about 1 bed volumes and especially about ⅓ bed volumes, are taken off via manifold 60 and passed though lines 76 , valve 94 and line 92 to brine tank 102 .
The fresh brine employed in the regeneration steps is most commonly common sodium chloride solution. This regenerant solution commonly contains from about 2% by weight to about 15% by weight sodium chloride, especially 4 to 12% and more especially 5 to 10 and particularly about 8% by weight sodium chloride.
At this stage in the regeneration process, vessel 12 - 16 has been completely rinsed and is ready to be placed in service. Vessel 12 - 17 is full of partially used rinse water and vessel 12 - 18 is full of partially used regenerant brine. When the next vessel comes off line, for example vessel 12 - 1 , 12 - 16 will go into service. The regeneration cycle begins anew with fresh brine being fed into vessel 12 - 18 to displace brine into vessel 12 - 1 . Thereafter fresh rinse liquid will be added to vessel 12 - 17 to displace its rinse liquid contents to vessel 12 - 18 .
As can be seen, the one stage where liquid leaves the system during regeneration is when regenerant that has passed though two vessels and is sent to waste. In accord with this process the volume of such liquid lost from the system is made up by the volume of water displaced out of the vessel when it first enters regeneration and by the volume of fresh rinse water added to the system by the final rinse. Accordingly, the volumes of these several flows need to be coordinated to maintain a relatively constant system volume.
All of these valve and pump functions are controlled by a controller. Controller 104 opens and closes the various valves so that individual vessels can function as water purifiers or can be operated in regeneration or rinse modes. Controller 104 can operate on a preset time sequence, sequencing the various vessels through the different stations according to a preset schedule. Alternatively, controller 104 can operate based upon analytical results based on samples fed to it by sample lines 106 and associated analytical equipment which measures the composition of the outflows from individual vessels and cause the system to precess from station to station based on the results of these measurements. The presently preferred method of control processes the vessels based upon the volume of water passed through them and the operator's knowledge of the capacity of the resin beds.
Controller 104 is a programmable logic controller as is marketed by Alan Bradley or by Square D under the Modicon name. This computer-driven controller operates a program which translates a sequence of programmed commands into a series of signals which drive the various valves and pumps in the system in an appropriate sequence to carry out the process.
System 700 is shown with all in service vessels and all vessels in regeneration operating downflow and the vessel in final rinse operating upflow. As the various vessels cycle into these various stations the flow direction is set accordingly, not by repiping but rather by controlling valves and by the passing the flows through intermediate manifolds 59 and 60 , with controller 104 .
System 700 , with the flow directions just described, has proven very effective for treating water having nitrate as a principal contaminant.
A second embodiment of the overall system of the invention is shown in FIG. 8 as system 800 . System 800 includes sixteen vessels 12 - 1 through 12 - 16 . The numbering of elements of the process is in accord with the numbering used with FIG. 7 . Contaminated water is feeding through the resin beds in vessels 12 - 1 through 12 - 13 . Purified water is being withdrawn from these thirteen vessels through headers 42 - 1 and valve 64 - 1 , etc and collected in manifold 50 for use. Again, valves 64 - 1 through 64 - 13 all are shown with a dot to show a positive fluid flow.
Vessels 12 - 14 through 12 - 16 are not in service purifying water. The resin beds in vessels 12 - 15 and 16 are undergoing regeneration with a brine solution and the bed in vessel 12 - 14 is being rinsed to remove spent brine prior to being returned to service. As noted above, this regeneration could be carried out with substantial volumes of regenerant and rinse going to waste. It could also be carried out with substantially reduced waste, for example as follows:
In this representative preferred process, vessel 12 - 16 is taken out of service filled with water. Regenerant brine that has already been partially used by being first passed upflow through vessel 12 - 15 is passed through manifolds 60 and 59 and lines 74 and 76 to the bottom of vessel 12 - 16 and passed upflow through that vessel. The volume of this flow of brine is generally from at least about ½ of a bed volume to about 3 bed volumes and especially from about 1 to about 2 bed volumes. The first about ⅓ bed volumes of regenerant fed to vessel 12 - 16 displaces the water present in the vessel. This volume of water can be sent to product water or it can be discarded via line 90 , or it can be sent to the brine tank 102 via manifold 54 , valve 79 and line 77 . This last alternative is preferred. The remaining regenerant passing through vessel 12 - 16 at this stage can be recycled to the brine tank together with the water but preferably up to about one bed volume is sent to waste via manifold 54 , valve 79 and line 90 .
The volume of used regenerant fed to vessel 12 - 16 is equal to a volume of fresh regenerant fed to vessel 12 - 15 via line 53 and manifold 52 . Thus, at the completion of this stage of regeneration, vessel 12 - 16 is full of used regenerant and vessel 12 - 15 is full of fresh regenerant.
Controller 104 then reconfigures the valves associated with vessels 12 - 14 , 12 - 15 and 12 - 16 for the next stage of regeneration. In this stage, fresh rinse water is passed from manifold 50 through valve 64 - 14 upflow through vessel 12 - 14 . Vessel 12 - 14 is full of used rinse water previously added as will be described. The fresh rinse water, ½ to about 1 bed volumes and preferably about ⅔ of a bed volumes, pushes used rinse water from vessel 12 - 14 to manifold 59 and 60 and line 76 where it passes upflow into vessel 12 - 15 now pushing the fresh brine previously added to 12 - 15 before it. This about ⅓ bed volumes of fresh brine followed by some amount of rinse water, typically at least about ⅙ bed volumes to about 1 bed volumes and especially about ⅓ bed volumes, are taken off via manifold 54 and passed though valve 79 and line 77 to brine tank 102 .
At this stage in the regeneration process, vessel 12 - 14 has been completely rinsed and is ready to be placed in service. Vessel 12 - 15 is full of partially used rinse water and vessel 12 - 16 is full of partially used regenerant brine. When the next vessel comes off line, for example vessel 12 - 1 , 12 - 14 will go into service. The regeneration cycle begins anew with fresh brine being fed into vessel 12 - 16 to displace brine into vessel 12 - 1 . Thereafter fresh rinse liquid will be added to vessel 12 - 15 to displace its rinse liquid contents to vessel 12 - 16 , etc.
System 800 , with the flow directions just described, has proven very effective for treating water having arsenic as its principal contaminant.
Turning to FIGS. 9 and 10 , several details of the vessel 12 preferably employed in the process and system of this invention are shown. Vessel 12 holds resin bed 14 . Resin bed 14 substantially fills vessel 12 , for example filling at least about 85%, and preferably at least about 90% and more especially at least about 93% of the vessel volume. (In all cases these percentage fill values are based upon swollen resin in a ready to use state.) Resins suitable for use in water treatment units have been described in the art and are selected depending upon the nature of the contaminant being removed. Table I lists a variety of available resins which can be used and describes the contaminants which they remove.
TABLE I The ion exchange resins which are presently preferred for use in the process of the invention are strong base resins. These resins are based on various polymer structures such as polystyrene with cross-linkeres and with appropriate active groups such as quaternary ammonium attached: Prolate Strong Base Resins Type 1 and Type 2 Amberlite IRA-400 Amberlite IRA-900 Dowex SBR Ionac ASB-1 Ionac AFP-100 Dowex SBR-P Dowex 11 Duolite A-102-D Ionac ASB-2 Amberlite IRA-93 Amberlite IR-45 Purolite A-400 Purolite A-600 Ionac A-260 Dowex WGR Sybron SR6 Sybron SR7 Reillex ™ HPQ Resins (based on polyvinyl pyridene polymers) Nitrex
Other ion exchange resins which are applicable to the invention such as for treating various cations are strong acid or weak base type resins such as:
Amberlite IR-120 Ionac C-20 Prolate C-100 Ionac C-270 Amberlite-200 Ionac CFS
Generally, the strong base type I resins, particularly those based on polystyrene backbones, give good overall results removing nitrate and perchlorate as well as arsenic and the like and are preferred.
Fluid flows into and out of vessel 12 are through fluid ports 108 and 110 , located at opposite ends of the resin bed. In preferred embodiments of this invention, the fluid flows into and out of the vessel take place through fluid distributors, provided to spread the flow of liquid evenly over the resin bed and to achieve a consistent flow of liquid over the resin bed. This provides maximum efficiency during use in service and also during regeneration.
One approach to fluid distribution is to employ distributors such as 112 and 114 . These distributors may have a plurality of distribution laterals 116 , 118 , 119 and 120 extending radially from a hub 122 . Most commonly there are at least four laterals in each distributor with from four to eight and especially six laterals being most common. The distribution laterals each have a plurality of holes 124 through which liquid can flow. These holes can be essentially evenly spaced over the length of the laterals. It has been found that better results are often achieved if the holes are distributed more heavily on the outer ends of the distribution laterals. This tends to promote a more even and consistent flow over the bed of resin. On the upper distributor 112 the holes 124 are concentrated toward the outer end of the laterals. On the lower distributor 114 the holes 124 are spaced along the laterals but with the spacing between inner holes being greater than between outer holes.
Since the lower laterals may be buried in resin or may come in contact with resin lines during downflow operation, they commonly are shielded by a screen 126 which are closed by cap 128 .
The length of the distribution laterals is typically selected to give a distributor diameter (D D ) which is about 66% to about 75%, and especially about 70% of the inside diameter (D v ) of cylindrical vessel 12 .
The flow rate of fluid through the vessels can play a part in determining the efficiency of the system. Obviously, a very low flow rate would lead to a very low throughput for the system. Conversely, a very high flow rate could lead to inadequate treatment or inadequate regeneration or rinsing. On a commercial scale, the resin beds are from about two feet to about six feet in depth (length). Good results are achieved with such beds if the flow rate of liquid over the resin bed, either upflow or downflow, is from about six gallons per minute per square foot of resin bed area (gpmft 2 ) to about sixteen gpmft 2 . Flow rates of eight to fourteen gpmft 2 and especially about twelve gpmft 2 give very good results particularly, when flowing contaminated water over the resin beds for treatment. While these flow rates may used during each of the process steps, during regeneration and rinse it is generally advisable to keep the flow rates of regenerant and rinse at or about eight gpmft 2 .
A major process advantage of the present is the higher regeneration efficiency, as measured by smaller volumes of brine and rinse being sent to waste, which it achieves.
As illustrated in FIGS. 11 and 12 , with a single fixed bed, during regeneration, the contaminant level in the waste brine is initially quite high but drops rapidly as the regeneration is completed. This means that the overall concentration is not optimal and that the volume of brine is large.
As also shown in FIGS. 11 and 12 with the present invention, it is possible to route a regenerant brine through 2, 3, 4 or more vessels in series, varying the flow upflow and downflow as desired. This allows the brine exiting a first vessel at the end of its regeneration cycle and thus incompletely loaded with contaminant, to pass through one or more additional, more contaminated, vessels and then to become fully leaded before being sent to waste. This multi-vessel regeneration is referred to as a “gradient regeneration”.
The brine savings produced by the system of this invention over that of the fixed bed system is at least 25% and often 50% or greater.
A typical regeneration/rinse cycle, using the present invention generates at most about one bed volume of total waste.
When the regeneration begins, used brine first pushes ⅓ bed volumes of water out of the newest, most contaminated, vessel. This ⅓ bed volume of water is passed to the brine make up tank.
Next one bed volume of used brine is passed through that vessel. This one bed volume of used brine is sent to waste. This is the sole fluid sent to waste during this regeneration cycle. About ⅓ bed volumes of fresh brine have been fed to the preceding vessel during this cycle but this material only leaves the system as used brine exiting the most contaminated vessel.
During the rinse portion of the cycle, no waste is generated, instead the waste from generates ⅔ of a bed volume of spent rinse water which is passed to the brine make up tank as make up. Thus, overall waste levels at least as low as 0.3% are achieved during nitrate removal and as low as about 0.01% or lower with arsenic removal.
The invention will be further described with reference to the following Examples in which the removal of representative contaminants is demonstrated.
EXAMPLE 1
Nitrate Removal
This example shows the removal of nitrate ion from a ground water source as practiced on a continuous, pilot scale basis. A representative analysis of the feed water showed the following:
Typical
Actual
nitrate
45-200
mg/L
52
chloride
35-200
mg/L
44
sulfate
0-300
mg/L
100
bicarbonate
60-200
mg/L
98
The product water contained on average 6 mg/L of nitrate and less than 1 mg/L of sulfate.
The feed water was fed into a purification system substantially as shown in FIG. 7 as 700 . Sixteen to eighteen vessels were used at various times during the run. Each vessel was 36 inches in diameter by 48 inches high. Each contained about 25 ft. 3 of an ion exchange resin. Commercial strong base type I an ion exchange resin having a DVB cross-linked polystyrene matrix and type I quaternary ammonium functional groups was used. This resin was in the form of beds of typical resin bed size 1/16- 1/64 inch diameter. These vessels were placed in service together and removed from service sequentially. Eventually the vessels were cycling so that one vessel placed in service became loaded with contaminant, and thus in need of regeneration about every 35-45 minutes. All 16-18 vessels were regenerated about once every 10-12 hours At most times 13 to 15 vessels were in service with three vessels in regeneration and rinse. The nominal flow rate of the system was 1000 gpm. The vessel regeneration cycle was one recycle every 300 bed volumes of treated water.
Brine (8% by weight NaCl) was used as regenerant.
The flow directions were as follows:
Absorption
all downflow
Regeneration
all downflow (cocurrent) or last stage upflow and
others downflow
Rinse
upflow or downflow with final stage upflow
(countercurrent)
This arrangement gives high nitrate removal efficiency which saves operating costs and minimizes the production of waste.
The regeneration cycle is as described with reference to system 700 in FIG. 7 . At the completion of the adsorption step the ion exchange bed had contaminants distributed as follows: The nitrate contaminant is concentrated at the bottom of the bed and sulfate is concentrated at the top of the bed.
The first stage of regeneration, with used brine, removes sulfate and nitrate. Most of the sulfate will be removed from the column and only a portion of the nitrate will be removed, leaving some nitrate at the bottom of the column. The second stage of regeneration with fresh brine polishes this bed by removing remaining traces of nitrate.
The bed was then rinsed with water as shown in FIG. 7 .
The overall efficiency of the process is very high. Nitrate has been reduced to 6 mg/L. The volume of waste was 0.3%, based on the volume of purified water generated.
EXAMPLE 2
In this case perchlorate (in the range of 10 to 1000 micrograms/liter), a contaminant in addition to nitrate, is present in the water supply. The process must now be able to remove nitrate and perchlorate. The ion exchange beds 14 in vessels 12 which are effective for removing nitrate will remove perchlorate as well. The regeneration set forth in Example 1 is not optimal in the case of a nitrate and perchlorate-loaded resin, however. Typically, perchlorate is bound very tightly to the resin and is often localized at the leading edge of the absorption beds. Regeneration with brine (as described in Example 1) is the regeneration method of choice but cocurrent brine flow (that is downflow when absorption has been downflow) is less effective than is the case following nitrate absorption. Regenerating the bed initially in a downflow (cocurrent) mode, the perchlorate is not entirely removed from the bed but to some extent is only transported downward into the bed.
The invention allows the process to be easily changed to enable it to remove both perchlorate and nitrate from the beds in an efficient manner during regeneration. By reconfiguring the flows with controller 104 , changes can be carried out. First, if a longer regeneration period is needed, the proportion of vessels in regeneration can be increased. For example, instead of 13 vessels in service, two in regeneration and one in rinse, 12 vessels could be left in service while three are in regeneration and one is in rinse. Second, the flow direction of the regenerant brine can be redirected in one or more vessels to achieve countercurrent regeneration favored when perchlorate is present.
In this example, the vessels could be configured as set forth in FIG. 8 with 16 vessels in total and counter current regenerant flow.
As previously described, fresh brine fed to the second regeneration stage displaces spent brine which in turn displaces water present when the vessels are taken out of service. The rinse cycle described in example 1 is used. The typical duty cycle and waste generation levels would be essentially the same as those demonstrated in Example 1.
Nitrate removal would remain at the same high levels shown in Example 1. Perchlorate levels would be significantly reduced, as well.
EXAMPLE 3
Arsenic Removal
The system of the invention is useful for removing arsenic from water. An overall process is illustrated in FIG. 13 .
The ion exchange unit was substantially in accord with system 800 in FIG. 13 . Since this was a test system, the number of vessels was reduced to six, three in absorption, two in regeneration and one in rinse. In a commercial scale unit, additional vessels would be present in service in absorption for a total of at least 10 vessels. The beds were each 36 inches in diameter and about 48 inches deep. Treated water was removed via line 136 .
The water being treated was fed through line 130 to oxidizer 132 and had the following representative composition.
Anions
2.93
mg/L
Ca
20.00
mg/L
Cl
7.60
mg/L
Mg
13.00
mg/L
Mn
79.00
mg/L
NO 3
1.00
mg/L
K
24.00
mg/L
Na
22.00
mg/L
As V
0.012
mg/L
As III
0.011
mg/L
This water feed was treated with chlorine (0.2 mg/L) (0.2 ppm) to oxidize the AsIII to AsV. Any equivalent oxidizer, such as 0.2 to 5 ppm chlorine or the like, can be used. It should be pointed out that this oxidation is a very conventional step in the industry as it is common to treat water with about 0.5 ppm of chlorine during a conventional water purification scheme. It is not necessary to treat the water twice with chlorine.
The water feed, as treated in the oxidizer, was fed to the ion exchange unit at a rate of 10 gpm/ ft .
Arsenic levels were reduced to below the analytical detection limit of 0.001 mg/L after 300 bed volumes of water had been fed per bed. This level of performance was observed in samples taken at 3100 bed volumes and out to beyond 7500 bed volumes. At that time, beds were taken out of service sequentially to verify the efficacy of the regeneration steps.
The regeneration sequence described with reference to system 800 depicted in FIG. 8 was used. The regenerant brine was a 7-8% by weight sodium chloride brine. The volumes and flow sequences described with FIG. 8 were used.
The flow directions were:
Absorption—downflow
First stage Regeneration—upflow
Second stage Regeneration—upflow
Rinse—upflow
The spent regenerant taken off of the first regeneration stage as effluent to waste via line 138 contained high levels of arsenic. The arsenic in this waste was precipitated by adding FeCl 3 solution via line 142 to the effluent. 20 g FeCl 3 was added per gram of total arsenic in the waste. The FeCl 3 converted to Fe(OH) 3 and Fe(H 2 AsO 4 ) 3 which precipitated. The product, including the combined precipitate was passed via line 144 to filter 146 . The solids were recovered in filter 146 and removed as solid toxic waste via line 148 . Spent brine, with its arsenic removed, was discharged via line 150 .
This example demonstrates that arsenic can be removed continuously from water flows to levels below the analytical detection limit using the present invention's ion exchange system. The regeneration cycle is at least 3000 bed volumes, the volume of water treated even at the scale of this example, with 10 to 20 columns in use can range from 1000 to 2000 gpm. The liquid waste effluent can be rendered nontoxic by a simple precipitation process.
The foregoing has described the principles, preferred embodiments and modes of operation of the present invention. However, the invention should not be construed as limited to the particular embodiment discussed. Instead, the above described embodiment should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by worker skilled in the art without departing from the scope of the present invention as defined by the following claims. | The disclosed invention is a fixed bed ion exchange water purification system. It employs a combination of electronically controlled process steps and specific systems configurations to duplicate the effects of moving resin beds from one operating position to another as is required in moving bed ion exchange water purification systems. The invention combines features of single fixed bed ion exchange systems with those of a moving bed system. The invention applies to the treatment of water having typical industrial and drinking water concentrations of various ions. | 1 |
BACKGROUND OF THE INVENTION
My invention relates to skiing accessories, and more particularly to an improved means for protecting, holding, carrying and/or temporarily storing skis in a manner that will respect public safety. Skis tend to be long and they have to be carried with both hands with a cradle-type grip or placed on the shoulders and held with one or two hands. They tend to separate easily. While in transport by ground or air, the skis, particularly the tips, can be damaged.
A major problem is to get the skis from the means of transportation to the ski lift area. Since there are sharp edges and tips on the ski, injury to nearby people and property can occur. There is no satisfactory retaining means that can hold the skis together, protect the skis from damage, minimize injury to others, and allow easy application and removal.
U.S. Pat. No. 4,152,002 discloses a ski boot carrier which uses the skis, themselves, as the lever arm. The skis simply are received within a sleeve 23. The flat portions of the skis are used. While this does provide a means to carry not only the skis, but also the boots, it does not protect other people or property and the ends of the skis, and can not be used for transport nor provides any means of temporary storage.
U.S. Pat. Nos. 1,957,577, 3,051,210 and 3,253,627 are all directed to covers for golf clubs. These were the closest references found that were directed to coverings for odd shapes. The '577 patent shows a double cover with what might be characterized as a form of flexible bridge. However, there is no structure that could support the skis to suggest solutions for the prior mentioned problems. Sometimes straps are used to wrap-tie the skis together, but again it does not solve or suggest a solution for the above problems.
OBJECTS AND ADVANTAGES OF THE PRESENT INVENTION
Accordingly, it is among the principal objects of the present invention to provide an improved ski accessory for holding skis together.
Yet another object of the present invention is to provide an improved ski accessory which will protect the skis while on ground, sea or air transportation.
Yet another object is to provide an improved ski accessory which, when being transported by a person will minimize injury to nearby persons and property.
Still yet a further object of the present invention is to provide an accessory of the character described which is designed for easy engagement and removal.
Yet another object of the present invention is to provide a device of the character described which will make it easy to store skis at least on a temporary basis.
Still another object of the present invention is to provide an improved ski accessory which will fit all skis, regardless of their length and accommodating for variations in width.
A further object of the invention is to provide a protecting and holding accessory which is capable of absorbing shock and punishment to a high degree without being damaged or causing damage to the skis.
A feature of the invention is to provide an invention which will reduce the volume of material used, making this reduction an integral part of the invention.
Yet another feature of the invention is to provide the lowest vertical point of the invention with a drain to prevent water damage occurring when the skis are stored.
Still yet another feature of the invention is to provide a two part accessory in which the bottom part is received within the top part with means to insure a normally non-permanent securement when not in use.
Still yet another object of the present invention is to provide an accessory of the character described which will be simple and economical to manufacture and yet be durable to a high degree in use.
The invention consists of a top sleeve member comprising two symmetrical, outwardly flaring ski shovel receptacle means or wings. They are joined by a flexible bridge member to guarantee that they do not separate. These wings receive the shovel portion of the skis. The fit is designed to be snug. As a result the member is made of a durable but sufficiently flexible plastic, rubber or similar materials. Examples of such materials are rubber, polypropylene and polyurethane.
The outer walls of the receptacle members are provided with rather large openings. The inner walls are provided with smaller openings designed to snugly receive the bottom sleeve member as hereinafter described.
The bottom sleeve member is also made of a flexible material but with a somewhat less resilient bottom portion. The same material can be used; it can just be made thicker than the top member. This member is designed to snugly receive the tails of pair of skis. Once again, they are snugly received. The bottom wall has a drain to allow any water from snow, etc., to leave the interior receptacle and thus eliminate any damage that might otherwise be caused should the skis be allowed to sit for any period of time.
The bottom member also is formed with two vertical, parallel ribs in spaced apart relationship. When the accessory is not in use the two wings of the top member are folded upwardly against themselves around the flexible bridge. The bottom member is then inserted through the openings with one of the ribs forced through the two inner openings. Because of the snug fit the outer surfaces of the inner walls of the wings abut the ribs, thus providing a simple means of retaining the two parts of the accessory in engagement when not in use. By simply pulling at the bottom member, the rib forces the inner walls to yield, causing the two parts to separate for use.
Placing the top member wings over the shovels of the skis and the bottom member over the tails the skis are engaged in a solid, firm manner.
The above description, as well as further objects and advantages of the present invention will be more fully appreciated with reference to the following detailed description of a preferred, but nonetheless illustrative embodiment of the invention, when taken in conjunction with the following drawings wherein:
FIG. 1 is a perspective view of the top sleeve member embodying my new invention;
FIG. 2 is a partial perspective view of the member covering the shovels of the skis;
FIG. 3 is a cross-sectional view taken along the lines 3--3 of FIG. 2;
FIG. 4 is an exploded perspective view of the tails of the skis and a bottom sleeve member for covering the tails;
FIG. 5 is a cross-sectional view of the member engaged on the tail of the ski;
FIG. 6 is a cross-sectional view taken along the lines 6--6 of FIG. 5;
FIG. 7 is a perspective view of the bottom sleeve member inserted into the openings of; the top member for storage purposes; and
FIG. 8 is a cross-sectional view taken along the lines 8--8 of FIG. 7.
DETAILED DESCRIPTION OF THE INVENTION
Turning in detail to the drawings and in particular to FIGS. 1, 4 and 8, there is shown an accessory 10 for protecting and holding skis together broadly comprising a bottom sleeve member 12 and a top sleeve member 14.
This accessory is designed for use with a pair of skis, and more specifically with snow skis. A typical pair of skis (FIG. 3) includes a first or right ski 16 and a second or left ski 18. The first ski as considered from the vertical has an upper end or shovel 20 which is flared outwardly in the well-known shape. The shovel is defined by an outer surface 22 and an inner surface 24. The other or bottom end of the right ski (FIG. 4) the tail 26 is defined by an outer surface 28, a bottom surface 30 and an inner surface 32. Similarly, the left ski 18 has a shovel 34 defined by an outer surface 36 and an inner surface 38. The tail 40 is defined by an outer surface 42, a bottom surface 44, and an inner surface 46.
The top sleeve member includes a right wing or ski shovel receptacle means 48 (FIG. 1) made of a standard flexible plastic or rubber. It is similar in appearance to the shovel and is flared outwardly. It has a receptacle 49 to receive the shovel and has an outer wall 50 defined by an outer surface 52 and an inner surface 54. It further includes a front side wall 56 defined by an outer surface 58 and an inner surface 60. Oppositely disposed is rear side wall 62 defined by an outer surface 64 and an inner surface 66. The side walls meet at tip 68. Completing the enclosure is inner wall 70 defined by outer surface 72, inner surface 74, and bottom surface 75. The inner wall 70 has an inner opening 76 (FIG. 2) with a top wall 78, side walls 80, and a bottom wall 82.
The left wing or ski shovel receptacle means 84 (FIG. 1) has an outer wall 86 defined by an outer surface 88 and an inner surface 90. Secured to it is front side wall 92 defined by outer surface 94 and inner surface 96, as well as rear side wall 98 defined by outer surface 100 and inner surface 102. The side walls come together at tip 104. The receptacle 105 is enclosed by inner wall 106 defined (FIG. 3) by outer surface 108 and inner surface 110 with bottom surface, 111. The inner wall 106 has an inner opening 112 (FIG. 1) with a top wall 114, side walls 116 and a bottom wall 118.
The right wing 48 has an opening 120 (FIG. 1) in its outer wall 50. It is defined by side walls 122 and bottom wall 124. The openings are shown as resembling an isosceles triangle. It is also larger than inner opening 76. In a similar manner the outer wall 86 of left wing 84 has an outer opening 126 (FIG. 2) defined by side walls 128 and bottom wall 130.
The two shovels receptacle means 48, 84 are joined at the bottom surfaces 75,111 of their inner walls 70, 106 by a bridge 132 (FIG. 1) defined by an inner surface 134 (FIG. 3) and an outer surface 136. The bridge joins the inner walls at edges 138, 139. The bridge may have holes 140 to lessen the amount of material required to fabricate the article and to increase the flexibility of the bridge. The purpose of the bridge is to hold the two wings together and thus holding the two skis together. Accordingly, the bridge in addition to being constructed as shown could be any type of connection, made of any appropriate material. For example a single (or multiple) perpendicular strip would be appropriate. An elastic hook could also be used. Furthermore, the bridge could join the wings to each other at their tips or side walls as well as the bottom walls.
The bottom sleeve member 12 (FIG. 4) has a front wall 142 defined by an outer surface 144. Protruding from this surface are two vertical, parallel, spaced ribs 146, 148 for the purpose to be described hereafter. The wall is also defined by an inner surface 150 (FIG. 6). Furthermore, the member has two oppositely disposed side walls (FIG. 5) 152 with inner surface 154, as well as a rear wall 156 with outer surface 158. Again in a similar manner protruding from this surface are two ribs 160, 162 oppositely disposed from and aligned with ribs 146, 148. The rear wall also has an inner surface 164. The bottom wall 166 is defined by an inner surface 168 with a drain hole 170 passing through to an outer surface 172. The walls 142, 156, 166 define a receptacle 173. Alternatively, there may be a plurality of drain holes, or the hole configuration may be replaced by other shapes such as a slit. Furthermore, a hole (or slit) 174 may be positioned in one or both of the side walls 152 to prevent a vacuum pressure from stopping easy draining.
In use the two members 12, 14 are stored together as seen in FIGS. 7 and 8. The wings 48, 84 are pivoted around bridge 132 toward each other as seen in FIG. 7 and member 14 is inserted through openings 76, 112. The dimensions of the openings are the same in configuration to the member 14 except they are slightly larger. As the member 12 is forced through the openings (as well as the larger openings 120, 126) the ribs 146, 148, 160, 162 press against the walls 80, 116 which yield an firmly grasp the ribs 144, 158 of the walls 142, 156. The ribs then are received within the interior space as best seen in FIG. 8, being on the outside of the walls 80, 116. The two members will not separate, since sliding movement is stopped by the ribs.
When it is desired to use the accessory with skis, the members are separated. The top member 14 is then stretched over the shovels of a pair of skis as shown in FIG. 3. The tails of the skis are then held together (FIG. 4) and they are forced into the receptacle in the bottom member 14 (FIG. 6). Since the upper portion 176 of the bottom member 12 is thinner than the bottom portion 178 it is more flexible, making it easier to insert the tails of the skis. The normal bowing in the skis and the resilience in the members cause a reliable and secure fit. The members have a smooth, soft finish which aids in preventing bodily harm to others or personal injury. The user thus has a simple and inexpensive way to protect transport and store skis. Should the skis be placed in the bottom member when there is still snow on the tails, the drain will prevent melting snow water from accumulating within the bottom member 12.
My construction solves all of the problems faced in the prior art. My two part ski accessory holds a pair of skis together in a secure and reliable fit. The top member covers and protects the tips of the skis when they are carried by an individual, transported in a vehicle or on a plane, or sent by United Parcel, for example. By covering the shovels, tails and associated edges injury to nearby people or property is minimized. Finally, the simplicity of placing the members on the skis, or removing them, as well as securing them together when not in use, adds to the pleasure and desire to use the invention.
As can be seen, the present invention provides a significant advance over the state of the technology. As numerous additions, modifications and constructions can be performed within the scope of the invention, such scope is to be measured by the claims herein. | An accessory for protecting and holding skis together which includes a top member and a bottom member. The top member is formed of two flexible wings conforming in shape to the shovel of a ski with a receptacle to receive the shovel. The wings are joined usually at their bottom surfaces of their inner walls by a thin flexible bridge. The walls of the wings have openings which are substantially aligned with each other when the wings are folded against themselves. The bottom member also forms a receptacle to receive the tails of the ski and is sized to be received within the openings of the walls of the wings. | 0 |
BACKGROUND OF THE INVENTION
This application is a continuation in part of Ser. No. 07/135,996, filed 12/21/87.
FIELD OF THE INVENTION
The present invention relates to a device which protects the thumb. In particular the present device restricts and preferably prevents radial deviation of the proximal phalanx and rupture of the metacarpalphalangeal (MP) joint ulnar collateral ligament. Related Art
The injury resulting from radial deviation of the proximal phalanx of the thumb is attenuation or rupture of the ulnar collateral ligament. The condition has been commonly called "gamekeepers thumb", which apparently derived from the English gamekeepers method of breaking the neck of a hare which caused great stress to be placed on the ulnar collateral ligaments; and now the term "skier's thumb" is the more frequent term.
Skier's thumb is a common injury which results from a forward fall by the skier which forces the ulnar aspect of the thumb against the planted ski pole. The thumb is pulled into forced abduction and caught between the pole grip and the strap. This places a tremendous force on the structures around the metacarpalphalangeal (MP) joint. The collateral ligament may be either torn or a portion of the proximal phalanx avulsed at the area of its insertion.
This is a very serious injury, which for some professionals can be career ending, such as surgeon, violinist or pianist. The normal corrective treatment would be an immobilizing cast for a minor case, usually for about four weeks, or in the more severe cases where there is a rupture; surgery is indicated. Generally, recovery is less than 100% of the joint mobility prior to the accident.
The number of cases of skier's thumb has been increasing, due possibly to the crowded slopes, less skilled and able skiers and the so-called "hot dog" techniques.
U.S. Pat. No. 4,445,507 to Eisenberg discloses a glove having a retainer (rigid member) disposed radially to the thumb which is intended to restrict the movement of the thumb portion of the glove radially. Additionally, straps going to the fingers are intended to give further stability. This arrangement, however, will not achieve the desired result. When the thumb is stressed as with a ski pole the retainer will tend to slide out of the way of the force and to dig into the hand but the MP joint will still radially deviate.
In U.S. Pat. No. 4,658,441 to Smith, a thumb support made of a flexible sheet of material which straps around the hand and thumb is described. The specific purpose for the device is not given, other than as a thumb support. It would appear to be a splint to provide isolation from the thumb from index finger. The light weight flexible material used would not provide the rigidity necessary to keep the MP joint from opening up under severe stress. Further, there is no rigid three point fixation.
It is an advantage of the present device that it will restrict (prevent in most situations) the radial deviation of the thumb proximal phalanx and the consequent damage to the ulnar collateral ligament of the MP joint. It is a feature of the present invention that although the thumb metacarpalphalangeal joint is restricted in its flexion (i.e. stabilized at a selected functional flexion) the interphalangeal joint retains most of it flexion. Thus, it is an overall advantage of the present invention that the thumb is truly protected, but the functionality of the thumb, in skiing or other activities is substantially retained.
SUMMARY OF THE INVENTION
Briefly the present invention is a device which is slipped onto the user's thumb and held there by its conforming design (conforming to the user's hand). With the exception of the dorsal slot, the device preferably encompasses and covers the area of the thumb described by that portion of hand (including bones and overlying soft tissues) comprising about the distal 80% of the first metacarpal, the thenar eminence, approximately the radial 50% of the first web space, the metacarpalphalangeal joint, and the proximal thumb phalanx up to but not including the condyles of the proximal phalanx. The dorsal slot extends from the distal end of the proximal phalanx past the MP joint. To seat the device on the user's thumb, the dorsal slot is placed over the ulnar surface of the thumb, rotated approximately 90% (ulnar to dorsal to radial) while pressed toward the hand such that the distal end of the device slips proximal to the proximal phalanx condyles at the interphalangeal joint so that the device comes to rest in a position which stabilizes the thumb metacarpalphalangeal joint in slight flexion (about 25°-35°), where it prevents radial deviation of the MP joint and permits full flexion of the interphalangeal joint. The dorsal slot is necessary and allows the device to slip over the user's thumb, rotate and seat in place.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan view of one embodiment of a stock material corresponding to a device as shown in FIGS. 2-5.
FIG. 2 is a frontal elevational view of the device of FIG. 3.
FIG. 3 is a left side elevational view of one embodiment of a device for the left hand.
FIG. 4 is a top plan view of the device of FIG. 3
FIG. 5 is a dorsal view of a hand with the device of FIGS. 2-4 in place.
FIG. 6 is a plan view of one embodiment of a stock material corresponding to a device as shown in FIGS. 1-9.
FIG. 7 is a front elevational view of the device of FIG. 3
FIG. 8 is a left side elevational view of one embodiment of a device for the left hand.
FIG. 9 is a top plan view of the device of FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 6 represent two embodiments of blanks useful in one method of fabrication of the present device. Both of these blanks are used when the device is molded on a mold of either standard size hands or of a particular person when the device is custom made. The blank of FIG. 1 related to FIGS. 2-5 is a "global" blank, since it can be used for various size of hands with the terminus 10 being allowed to overlay the middle aspect of the metacarpal radial side 8 of the device. The overlap 22 has no effect on the function or usefulness of the device, but is not aesthetically appealing. The terminus 10 has a rounded, i.e., curved configuration, since it is exposed (generally gloves, will be worn over the hands when the device is used) and shape edges are not desirable. Although the drawings and descriptions are shown for a device for use on the left hand, it should be appreciated that the device for the right is the mirror image and in every way a reversed duplicate of the illustrated device.
The terminus 10a of FIG. 6 related to FIGS. 7-9, is cut so that the terminus 10a does not overlap the middle aspect of the metacarpal radial side 8 of the device, but instead abuts the radial side of the 12 of the dorsal slot 2.
The phantom line 32 shows where the terminus 10a abuts radial slot side 12. If the material used to mold the device is sufficiently softened, e.g., by heating, the juncture 32 may not show.
The present device can also be vacuum formed, extrusion molded, or injection molded in which case the junction 32 will not exist.
It is contemplated that device will be formed of a plastic material. Those formed from the blanks of FIG. 1 and 6 will desirably be thermoplastic, at least at the time the device is fabricated. Plastic materials which crosslink after molding or by exposure to ultraviolet light are useful. However, the plastic material may be thermoplastic, so long as it is rigid under the conditions of use and general under ambient temperature, i.e., up to 130° F. Preferably the device is formed from a material, e.g. plastic, which is sufficient rigid to prevent radial deviation of the thumb at the metacarpalphalangeal joint.
The entire device is rigid. The rigidity which it imparts to the MP joint is what makes it useful. Whatever the method of manufacture used, the device is a rigid structure which surrounds and engages the proximal phalanx portion 24 of a thumb, up to but not including the condyles 26 of the proximal phalanx 24 and having a flared lip 20 about the phalanx opening 18. The flared lip is most pronounced between the radial and ulnar aspect which is the flexion direction of the distal phalanx 28. There is a dorsal slot 2 which prevents any structure of the thumb by the lip 20. The dorsal slot 2 is defined by ulnar side 14 and radial side 12.
The ulnar aspect 6 is smaller than the radial aspect 4 of the device, with the radial aspect 4 extending along and over a portion (about 60-90%) the first metacarpal 30. The rigidity of the device provides a specific predetermined flexion of the metacarpalphalangeal joint 32. The predetermined flexion, angle a is one that corresponds to the natural flexion when the hand is at rest, i.e., about 25° to 35°. However, by terminating the device at the flared lip 20 just below the condyles of the proximal joint, substantial fully flexion of the interphalangeal joint 34 is preserved. The MP joint is 32 substantially immobilized by the device when it is placed on the hand by inserting the thumb 36 through the hand side opening 16. The device is mounted by inserting the thumb 36 through opening 16, with the dorsal slot 2 ulnar and rotating the device ulnar to dorsal to radial aspect 90° while depressing the device toward the hand. This allows that lip to seat below the condyles of the proximate phalanx with the slot being positioned dorsal to the thumb. Rigid three point fixation is provided about the metacarpalphalangeal joint.
The device is generally conformed to the shape of the hand so that it is comfortable to wear for extended periods, on both hands. The extended portion which extends over the first metacarpal provides a brace which shifts any force applied to the thumb to the hand 38 and wrist 40, which are far more massive and generally capable of withstanding the force from the gripped ski poles (not shown) as they push against the ulnar aspect of the device. It is contemplated the device is to be made in different sizes in accordance with the standard ring size of the thumb, which will allow the user to measure the thumb with a ring sizer and select the appropriate sized device (± one ring size).
Although not shown the device may be incorporated in a glove or mitten. | A device to encompass and engage with the thumb to substantially immobilize the metacarpalphalangeal joint, thereby preventing radial deviation of the thumb phalanx while leaving the interphalangeal joint with substantially full flexion. | 0 |
FIELD OF THE INVENTION
[0001] The field of this invention is actuating systems for downhole tools and more particularly systems that employ relative movement resulting from longitudinal shrinkage of tubulars on expansion relative to another body that does not longitudinally shrink at the same time.
BACKGROUND OF THE INVENTION
[0002] Setting downhole tools has in the past involved mechanical movements that are actuated by rotation, pulling, setting down weight or by tools that hang onto one component while driving another mounted to it. Other motive forces have been hydrostatic pressure, explosive charges and various forms of stored potential energy that is released at the appropriate time to set a tool.
[0003] More recently downhole tools such as packers have been set with expansion of the underlying mandrel from within. The sealing element is simply pushed out to contact the tubular in the surrounding wellbore or against the formation if it set in an open hole portion of the wellbore. While expansion applies a radial force to push the sealing element into a sealing contact, mere radial expansion simply brings a sealing element into proximity of the surrounding tubular or the wellbore but does not necessarily apply or more specifically maintain a longitudinal compressive force on the sealing element to help it maintain the seal.
[0004] The present invention seeks to take advantage of the longitudinal shrinkage that results from radial expansion. A body is mounted to the radially expanding mandrel that accommodates such expansion while retaining its longitudinal length or at minimum, not shrinking the same amount. The relative movement thus created, in the case of a packer, adds an element of compressive force longitudinally apart from the expansion force that acts radially. The underlying mandrel is then subjected to a residual longitudinal tensile force. As a result the packer can better continue to maintain a seal in cased or open hole. Other tool applications are envisioned beyond packers to take advantage of the relative movement made available between an expanding element and an adjacent sleeve that grows with it radially but does not shrink longitudinally to the same or any degree. Those skilled in the art will appreciate the full scope of the invention better from a review of the description and drawings of the preferred embodiment which appear below, with the understanding that the appended claims define the invention.
SUMMARY OF THE INVENTION
[0005] A downhole tool with a mandrel that is expanded downhole is further actuated due to relative longitudinal movement between the mandrel and a member that accommodates radial expansion without undergoing as much shrinkage as the expanded mandrel or any shrinkage at all. In a packer application, the packer can be set in open hole or cased hole and the relative longitudinal movement that results from mandrel expansion leaves a residual longitudinal compressive force on the sealing element and a tensile reaction force on the underlying mandrel.
DETAILED DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a run in position of a packer embodiment of the present invention; and
[0007] FIG. 2 is the view of FIG. 1 in the set position downhole.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0008] FIG. 1 shows a mandrel 10 with a sealing element 12 surrounding it. The sealing element 12 has a stationary anchor 14 preferably located at a downhole end 16 of the sealing element 12 . There is a releasable restraint 18 at the uphole end 20 of the sealing element 12 . The restraint 18 can be held fixed with a shear pin 22 that fails after expansion of the mandrel in a radial direction takes place, for reasons that will be explained below.
[0009] Mounted adjacent to the restraint 18 is a sleeve 24 that can be one or more pieces. Sleeve 24 abuts restraint 18 at a lower end 26 thereof. At the uphole end 28 there is a restraint 30 secured to mandrel 10 . This restraint can be an open ring or a series of spaced projections, for example, so as to not provide appreciable resistance to expansion of the mandrel 10 . A swage 32 is passed through the mandrel 10 to do the radial expansion.
[0010] In operation, the radial expansion of the mandrel 10 creates longitudinal shrinkage in it as the expansion progresses. This longitudinal shrinkage brings together restraints 14 and 30 . Since in the preferred embodiment the sleeve 24 is split, it accommodates expansion of mandrel 10 without meaningful resistance to such radial expansion. At the same time, however, there is no longitudinal shrinkage of sleeve 24 or at minimum less longitudinal shrinkage than the portions of mandrel 10 that underlie it. As a net result of the radial expansion of the mandrel 10 the sleeve 24 pushes first against the releasable anchor 34 breaking shear pin 36 and thereafter a compressive force is applied in the longitudinal direction by the sleeve 24 against the sealing element 12 to further energize it against the surrounding tubular or the formation (not shown). That longitudinal compressive force on the element 12 is in effect trapped by the setting of the sealing element 12 against the surrounding tubular or formation. The mandrel 10 retains a built in reaction force in tension to counteract the residual compressive force on the sealing element 12 .
[0011] Those skilled in the art can see the advantage of the invention in the context of a packer, as was described above in the discussion of the preferred embodiment. With the added exterior longitudinal force the thickness of the sealing element can be reduced and a good seal still obtained. The ability to use a thinner sealing element allows the assembly the ability to pass through a given drift diameter without getting stuck or damaged and leaves open the maximization of the mandrel inner bore. The reliance on the shrinkage of the tubular mandrel 10 from expansion allows for the design to be simple as no initial force must be stored and released as was done in the past with elements that were pre-stretched longitudinally and required complicated mechanisms to be locked until the point of delivery and then somehow released. These mechanisms took up some of the space that was saved by reducing the diameter of the sealing element in the past by pre-stretching it. The present invention, applied to setting a packer, does away with the complexity of locking arrangements to store potential energy force in stretched elements for insertion downhole. The reliance of differential or relative movement between two elements created as a result of radial expansion gives greater certainty of a sealing contact even when a thinner sealing element is used. The ability to trim the initial thickness of the element without needing to pre-stretch it also allows the use of an apparatus having a slimmer profile, fewer moving parts and enhanced reliability of operation.
[0012] While a split sleeve has been illustrated for 24 as the preferred embodiment, those skilled in the art can appreciate that other devices that will accommodate expansion of the mandrel 10 with little or no longitudinal shrinkage with respect to the mandrel 10 could be employed. Some examples of contemplated alternatives are roll pins, c-rings, a scroll or split sleeves that are solid or that have openings such as a structure made of rods. In essence, item 24 can be any mechanism that retains column strength while presenting low to minimal resistance to radial expansion of the mandrel 10 .
[0013] The releasable anchor 24 is optional and serves to retain the element 12 in position during run in. It can also be configured to be an extrusion barrier for when the element 12 is expanded and its internal pressure is increased.
[0014] While the preferred embodiment is to set a packer, a host of other downhole applications for setting a variety of other tools is contemplated. Anchors, slips and sliding sleeve valves are some possibilities. The invention is adaptable to many downhole applications where relative movement is used to operate the tool. In the context of a tubular expansion downhole, the invention uses the longitudinal shrinkage associated with radial mandrel expansion to create the relative movement for tool operation. Specifically in a packer application, the longitudinal compression of the element 12 leaves a residual tensile stress in the mandrel 10 . Subsequent cooling in the wellbore after expansion that would normally tend to shrink the mandrel 10 longitudinally so as to reduce the external applied compressive loading from the sleeve 24 would be resisted by the built in tensile load on the mandrel 10 between the restraints 14 and 30 . In this manner there is some temperature compensation built into the design that helps to keep the seal of the element 12 against the surrounding tubular or wellbore.
[0015] The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below. | A downhole tool with a mandrel that is expanded downhole is further actuated due to relative longitudinal movement between the mandrel and a member that accommodates radial expansion without undergoing as much shrinkage as the expanded mandrel or any shrinkage at all. In a packer application, the packer can be set in open hole or cased hole and the relative longitudinal movement that results from mandrel expansion leaves a residual longitudinal compressive force on the sealing element and a tensile reaction force on the underlying mandrel. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a transparent substrate with low birefringence, and in particular, relates to a transparent polyimide substrate polyimide having a birefringence below 0.005 for use as a flat panel display substrate.
[0003] 2. Description of the Related Art
[0004] In recent years, development of flat panel displays have trended toward larger and larger sizes, with glass, mainly used as the substrate for fabrication of flat panel displays. Accordingly, as development of flat panel displays trend toward larger and larger sizes, the weight of required glass makes the flat panel display heavier and costly due to increased raw material glass prices. Therefore, in order to meet requirements of lightness and thinness for flat panel displays, plastics is increasingly being substituted for glass, due to the easier processing of plastics and lighter weight.
[0005] Plastic substrates have high flexible and winding property, and may be used as the top and bottom substrates of a flexible flat panel display. Flexible flat panel displays utilizing plastic versus glass substrate have advantages such as a lighter weight, thinnest, having better impact resistant, being harder to break, being easier to carry, an ability to display on curved surfaces, an ability to wind and be dressed, and being able to be fabricated roll-to-roll, thus, reducing costs substantially. Therefore, new generation flexible flat panel displays have trended toward utilizing plastic substrates.
[0006] At present, the plastic substrate material most commonly used commercially contains polyimide, which has high heat-resistance, high chemical-resistance and high mechanical strength. However, the birefringence of polyimide typically used is too high, usually greater than 0.005. A high birefringence substrate reduces black and white contrast and increases color shift at wide viewing angles.
[0007] Therefore, developing a low birefringence polyimide material to be used as a transparent substrate for a flat panel display is desired.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention provides a transparent substrate with low birefringence below 0.005, comprising polyimide having a repeat unit of formula (I):
[0000]
[0000] , wherein each A of the repeat unit, being the same or different, represents an aromatic or aliphatic group, and at least one A is an aromatic or aliphatic group containing sulfonyl functionality; each B of the repeated unit, being the same or different, represents an aromatic or cycloaliphatic group; and n is an integer greater than one.
[0009] Furthermore, the transparent substrate may be used as the top and bottom substrates of a flexible flat panel display.
[0010] A detailed description is given in the following embodiments.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
[0012] Polyimide is characterized as having high heat-resistance, flexibility and high mechanical strength. The polyimide used herein is synthesized by reacting a diamine monomer comprising sulfonyl with a dianhydride monomer to provide a transparent substrate with low birefringence. The transparent substrate thus formed may be used as the top and bottom substrates of a flexible flat panel display.
[0013] The polyimide of the invention may be synthesized by reacting one or more diamine monomer comprising sulfonyl with one or more dianhydride monomer, wherein at least one diamine monomer has an aromatic or aliphatic group containing sulfonyl functionality. The diamine monomer used in the present invention may comprise bis[4-(3-aminophenoxy)phenyl]sulfonyl (3,3-BAPS), 4,4′-diaminodiphenyl sulfonyl (4,4-DDS), 3,3′-diaminodiphenyl sulfonyl (3,3-DDS), 2,2′-bis[4-(4-aminophenoxy)phenyl]propane (BAPP-m) or combinations thereof. The dianhydride monomer used in the present invention may comprise 3,3′,4,4′-diphenylsulfonyl tetracarboxylic dianhydride (DSDA), bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (B1317) or combinations thereof.
[0014] The polyimide is synthesized by a typical polycondensation which may be carried out in two different routes. In the first route, the synthesis is carried out in two stages. First, a diamine monomer is reacted with a dianhydride monomer in a polar solvent to form a precursor of polyimide, poly(amic acid) (PAA). Then the thermal imidization (300-400° C.) or chemical imidization of the precursors is performed to form polyimide. The reaction scheme of the first route is shown in formula (T1), wherein the diamine monomer is 3,3-BAPS, the dianhydride monomer is DSDA and the polar solvent is N-methyl-2-pyrrolidone (NMP):
[0000]
[0015] In the second route, a diamine monomer is reacted with a dianhydride monomer in a phenol solvent, such as m-cresol or Cl-phenol, and then the temperature is raised to reflow temperature to form a poly(amic acid) and simultaneously, imidization of the poly(amic acid) is performed, thus obtaining the polyimide. The reaction scheme of the second route is shown in formula (T2), wherein the diamine monomer is 3,3-BAPS and the dianhydride monomer is DSDA:
[0000]
[0016] In polyimide of formula (I) of the invention, A is an aromatic or aliphatic group containing sulfonyl functionality comprising:
[0000]
[0000] , wherein x and y are independently selected from the group consisting of: H, CH 3 , CF 3 , OH, Br, Cl, I, C 1-18 alkyl and C 1-18 alkoxy.
[0017] Furthermore, B of formula (I) may comprise
[0000]
[0000] , wherein x and y are independently selected from the group consisting of: H, CH 3 , CF 3 , OH, Br, Cl, I, C 1-18 alkyl and C 1-8 alkoxy, Z is O, S, CH 2 , C(CH 3 ) 2 , C(CF 3 ) 2 , SO 2 , Ar—O—Ar, Ar—CH 2 —Ar, Ar—C(CH 3 ) 2 —Ar, Ar—C(CF 3 ) 2 —Ar or Ar—SO 2 —Ar, and Ar is benzene.
[0018] In formula (I), n may be an integer between 10 and 10000.
[0019] In one embodiment, the polyimide of the invention may comprise formula (PI1) or formula (PI2).
[0000]
[0020] Moreover, more than one type of diamine monomer and dianhydride monomer may be used in the reaction for the polyimide. With two types of diamine monomer and two types of dianhydride monomer used, the polyimide thus formed may be represented by formula (II) and as mentioned above, at least one of the diamine monomer is an aromatic or aliphatic group containing sulfonyl functionality.
[0000]
[0000] , wherein C is an aromatic or aliphatic group containing sulfonyl functionality; E is an aromatic or aliphatic group without sulfonyl functionality; D and F are aromatic or cycloaliphatics; and a and b are integers great than 1, preferably between 10 and 10000.
[0021] In formula (II), a molar ratio of C to E may be between 9:1 and 1:9 and a molar ratio of C to E may be between 9:1 and 1:9.
[0022] In one embodiment, C of formula (II) may comprise
[0000]
[0000] , E of formula (II) may be
[0000]
[0000] and D and F may be the same, such as
[0023] A transparent substrate with a birefringence lower than 0.005, preferably 0.001, or more preferably 0.0001 can be achieved by a polyimide synthesized from a diamine monomer comprising aromatic or aliphatic group having sulfonyl functionality and a dianhydride monomer. Moreover, the transparent substrate may be used as top and bottom substrates of a flexible flat panel display. Because the birefringence of the transparent substrate of the invention is at least lower than 0.005, the problems associated with typical polyimide substrates, such as low contrast, color shift and light leakage may be improved.
[0024] The flexible flat panel display mentioned above may comprise a liquid crystal display or an organic electroluminescence display. If the flexible flat panel display is a liquid crystal display, a liquid crystal layer is placed between the top and bottom substrates. If the flexible flat panel display is an organic electroluminescence display, an organic electroluminescence layer is placed between the top and bottom substrates.
[0025] The synthesis procedures and results of relative tests of various examples of the polyimide in accordance with formulas (I) or (II) of the invention will be detailed in the following.
EXAMPLE
Example 1
polyimide PI1 (DSDA/3,3-BAPS)
[0026]
[0027] At room temperature, 5.9 g of 3,3-BAPS diamine monomer and 43.6 g of m-cresol were charged in a three-necked bottle under nitrogen atmosphere. After 3,3-BAPS was completely dissolved in m-cresol, 5 g of DSDA dianhydride monomer was added. After DSDA was completely dissolved, the reaction mixture was stirred for 1 hour to form a sticky polyimide solution. Thereafter, the polyimide solution was heated for reaction at 220° C. for 3 hours, during which time the water produced by the reaction was removed. Then, the reaction solution was dripped into methanol to participate the polyimide and dried in a vacuum oven for 12 hours, thus obtaining DSDA/3,3-BAPS polyimide.
Example 2
polyimide PI2 (B1317/3,3-BAPS)
[0028]
[0029] At room temperature, 17.1 g of 3,3-BAPS diamine monomer and 81 g of m-cresol were charged in a three-necked bottle under nitrogen atmosphere. After 3,3-BAPS was completely dissolved in m-cresol, 9.9 g of B1317 dianhydride monomer was added. After B1317 was completely dissolved, the reaction mixture was stirred for 1 hour to form a sticky polyimide solution. Thereafter, the polyimide solution was heated for reaction at 220° C. for 3 hours, during which time the water produced by the reaction was removed. Then, the reaction solution was dripped into methanol to participate the polyimide and dried in a vacuum oven for 12 hours, thus obtaining B1317/3,3-BAPS polyimide.
Example 3
polyimide P13 (B1317/3,3-BAPS/BPAA-m)
[0030] A molar ratio of 3,3-BAPS to BPAA-m is 8:2.
[0000]
[0031] At room temperature, 13.7 g of 3,3-BAPS diamine monomer, 3.2 g of BPPA-m diamine monomer and 107 g of m-cresol were charged in a three-necked bottle under nitrogen atmosphere. After 3,3-BAPS and BPPA-m were completely dissolved in m-cresol, 10 g of B1317 dianhydride monomer was added. After B1317 was completely dissolved, the reaction mixture was stirred for 1 hour to form a sticky polyimide solution. Thereafter, the polyimide solution was heated for reaction at 220° C. for 3 hours, during which time the water produced by the reaction was removed. Then, the reaction solution was dripped into methanol to participate the polyimide and dried in a vacuum oven for 12 hours, thus obtaining B1317/3,3-BAPS/BPAA-m polyimide.
Example 4
polyimide P14 (B1317/3,3-DDS/BPAA-m)
[0032] A molar ratio of 3,3-DDS to BPAA-m is 6:4.
[0000]
[0033] At room temperature, 5.9 g of 3,3-DDS diamine monomer, 6.5 g of BPPA-m diamine monomer and 90 g of m-cresol were charged in a three-necked bottle under nitrogen atmosphere. After 3,3-DDS and BPPA-m were completely dissolved in m-cresol, 10 g of B1317 dianhydride monomer was added. After B1317 was completely dissolved, the reaction mixture was stirred for 1 hour to form a sticky polyimide solution. Thereafter, the polyimide solution was heated for reaction at 220° C. for 3 hours, during which time the water produced by the reaction was removed. Then, the reaction solution was dripped into methanol to participate the polyimide and dried in a vacuum oven for 12 hours, thus obtaining B1317/3,3-DDS/BPAA-m polyimide.
Comparative Example 1
polyimide CPI1 (DSDA/CHDA)
[0034] At room temperature, 3.1 g of cyclohexanediamine (CHDA) diamine monomer and 50 g of m-cresol were charged in a three-necked bottle under nitrogen atmosphere. After CHDA was completely dissolved in m-cresol, 10 g of DSDA dianhydride monomer was added. After DSDA was completely dissolved, the reaction mixture was stirred for 1 hour to form a sticky polyimide solution. Thereafter, the polyimide solution was heated for reaction at 220° C. for 3 hours, during which time the water produced by the reaction was removed. Then, the reaction solution was dripped into methanol to participate the polyimide and dried in a vacuum oven for 12 hours, thus obtaining DSDA/CHDA polyimide.
Comparative Example 2
polyimide CPI2 (6FDA/TFMB)
[0035] At room temperature, 4.7 g of 2,2′-Bis(trifluoromethyl)-4-4′-diamino biphenyl (TFMB) diamine monomer and 60 g of m-cresol were charged in a three-necked bottle under nitrogen atmosphere. After TFMB was completely dissolved in m-cresol, 10 g of 4-4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) dianhydride monomer was added. After 6FDA was completely dissolved, the reaction mixture was stirred for 1 hour to form a sticky polyimide solution. Thereafter, the polyimide solution was heated for reaction at 220° C. for 3 hours, during which time the water produced by the reaction was removed. Then, the reaction solution was dripped into methanol to participate the polyimide and dried in a vacuum oven for 12 hours, thus obtaining 6FDA/TFMB polyimide.
[0036] Polyimide synthesized by Examples 1-4 and Comparative Examples 1-2 were fabricated into 10×10 cm 3 samples by blade coating. Then the birefringence of the samples was measured by Oji Scientific Instrument Kobra 21ADH and the results were shown in Table 1.
[0000]
TABLE 1
The birefringence of Examples 1-4 and Comparative Examples
1-2
Dianhydride
Birefringence of
monomer
Diamine monomer
polyimide
Example 1
DSDA
3,3-BAPS
0.0001
Example 2
B1317
3,3-BAPS
0.0002
Example 3
B1317
3,3-BAPS/BAPP-
0.0006
m(8:2)
Example 4
B1317
3,3-DDS/BAPP-m(6:4)
0.001
Comparative
DSDA
CHDA
0.005
Examples 1
Comparative
6FDA
TFMB
0.046
Examples 2
[0037] In Table 1, the birefringence of polyimide of Examples 1-4 is significantly lower than that of Comparative Examples 1-2. Specifically the birefringence of polyimide of Examples 1-4 is reduced by 5-500 times as compared to that of Comparative Examples 1-2. This may be attributed to the diamine monomer used in the polyimide of the invention having aromatic or aliphatic group containing sulfonyl functionality. Furthermore, the transparent substrate of the invention may be used as top and bottom substrates of flexible flat panel displays.
[0038] While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. | The invention relates to a transparent substrate with low birefringence. The transparent substrate comprises polyimide having a repeat unit of formula (I) and has a birefringence below 0.005:
, wherein each A of the repeat unit, being the same or different, represents an aromatic or aliphatic group, and at least one A is an aromatic or aliphatic group containing sulfonyl functionality; each B of the repeated unit, being the same or different, represents an aromatic or cycloaliphatic group; and n is an integer greater than one. | 8 |
FIELD OF THE INVENTION
[0001] The invention deals with a pharmaceutical composition comprising lectin KM+ to prevent and heal epithelial wounds. The invention also comprises the use of lectin KM+, obtained from the plant ( Artocarpus integrifolia ) or recombinant (expression heterologue) to prepare medicaments.
BACKGROUND OF THE INVENTION
[0002] Lectins are proteins, or glycoproteins of distribution located in the nature, that if the sugars bind selectively and reversibly. Two lectins had been isolated of seeds of Artocarpus integrifolia (jaca): jacaline and KM+, also called artocarpine. Lectin KM+ is obtained from the saline extract of seeds of Artocarpus integrifolia . The D-manose is leagued selectively being minority in the saline extract of the seeds (0.5% of total proteins), contrasting with the high concentration reached for jacaline (30% of total proteins), ligant lectin of D-galactose, contained in the same saline extract. Related studies to lectin KM+ mention the standardization to it of method for its purification, made from the saline extract of the seeds for chromatography of affinity in columns of immobilized sugar in two stages. In the first extract it is depleted of jacaline for adsortion to the immobilized D-galactose. To follow the depleted extract it with solution of D-manose is cromatographated in column of D-manose, eluded itself on lectin. The method provides homogeneous preparations of the lectin that had been used in the determination of its primary structure and in the attempt of crystal attainment for determination of the structure 3-D of the protein. The crystallization process is made difficult due to the small amounts of lectin provided by the purification method, reason for which the three-dimensional structure is proposal for molecular modeling.
[0003] The attraction of human neutrophils was the first described biological property of KM+, was detected by Saint-of-Oliveira et al. in 1994, through carried through assays in vitro and in alive. The molecular analysis of the phenomenon unchained for the stimulation of neutrophils for the lectin, led to the identification of that KM+ recognizes glicanes of cellular surface and that its linking to such glicanes active the cells, inducing its migration for small farms of bigger concentration of lectin.
[0004] The movement of neutrophil induced for KM+ if gives for haptotaxy, made possible for the fact of the lectin to be tetravalent, the domains of recognition of KM+ sugar form a bridge enter the surface of neutrophil and the laminine glycoprotein of the extracellular matrix. The ideal conditions for an adjusted cellular movement are established thus. This model of interactions revealed applicable for the induction of induced cellular movement for endogenous lectins, as galectin-3 and MNCF, as Dias-Baruffi et al, 1999.
[0005] The observation that the interaction of KM+ with glicanes of neutrofilic surface is capable to unchain dependent answers of cellular signaling, led to the assumption that the lectin could activate other immunitary cells and of this way to correspond to adjuvant an interesting one in immunization processes. It was verified initially that cells of the peritoneal socket of mice produced a great amount of interferon gamma under stimulation of KM+, and that such production was indirectly induced for the secretated I1-12 in high concentrations for the linking of KM+ to the surface of the macrophages, contained in the preparation of peritoneal cells. As such profile of citocines it is compatible with the establishment of imunitary answers of standard TH1, was opted to investigating the benefit eventually brought by the use of KM+ as adjuvant in the immunization against a sensible patogen answers TH1. The chosen model was of infection for Leishmania the major of mice of highly susceptible race to the patogen (BALB/c).
[0006] Previously to the infection the animals had been inoculated with a soluble antigen preparation of Leishmania (SLA) associate, or not it KM+. The study with L. major it showed that the animals that had received KM+ had substituted the standard of susceptibility for a standard of resistance to the parasite, as well as had inverted standard TH2 of citocines produced for a profile TH1. Thus the KM+ administration can intervene in an imunitarie reply of form to become it efficient against certain types of patogens. A time that this independent effect of the concomitant administration of the parasitic antigen, was transferred to consider it that KM+ is endowed with imunomodulator property, instead of adjuvant. As the rigorous purification of KM+ provided low income and that the excellent biological properties of KM+ imposed biotechnological investments that-made possible its application in ample scale, it was opted to proceeding the clonage and characterization from the DCNcA that codifies the lectin, aiming at to arrive the recombinant form of this lectin, through its heterolog expression. Such availability of recombinant lectin makes possible its application as therapeutical agent in injuries for burnings, as well as cicatrizant of injuries of diverse nature, as well as other pharmaceutical and/or biotechnological uses.
[0007] A library of DCNcA from extracted total RNA of jaca seeds was constructed ( Artocarpus integrifolia ). The DCNcAs had been clonated of directional form in the vector pSPORT-P of the Life Technologies. Such library, with approximately 13000 clones was organized in 136 plates of 96 wells (A01 the H12), contends supply in glicerol of each one of clones.
[0008] Based in the amino acid sequence of described lectin KM+ for Rose et al, (1999), and in the alignment of amino acid sequences of jacaline lectins and KM+ ( FIG. 1 , SEQ. ID NO:1), had been defined regions of KM+, distinct of jacaline, for which they had been drawn oligonucleotides depraved (oligo 10, oligo 11 and oligo 12, FIG. 2 ).
[0009] The election of the library of DCNcA of jaca seeds was carried through by PCR of matrix, from the mixture commanded of clones of DCNcA (mixture of the 136 clones in the A01 position, of the 136 clones of the A02 position and thus successively, until the 136 mixture of clones of the H12 position. The first plate I contend 96 136 mixtures of clones in each well, was used as source of DNA for the amplification for PCR. The first amplification for PCR was made with oligonucleotides SP6 (for the present sequence in the vector pSPORT-P) and oligo l2 . Of the result of the 96 amplifications, analyzed for eletroforese in gel of agarose, 28 reactions that had produced a band of equal or superior size the 500 pairs of bases (bp), for one second round of analysis had been selected. The 28 selected mixtures of clones had been used as source of DNA for an amplification using the oligonucleotides T7 (for the present sequence in the vector pSPORT-P) and oligo 10. The result demonstrated the presence of bands, with the waited size (500 bp or more), in 8 of the analyzed mixtures. Three of these mixtures had been chosen for one third round of analysis, of this time through, the re-amplification of the fragments gotten in first and the second rounds, however with different oligonucleotides (oligos 11 and 12). The amplification from the 3 mixtures (position E07, G07 and F08) resulted in the appearance of a band of waited size and confirmed the presence of clones of DCNcA for KM+, in each one of the 3 mixtures.
[0010] Of the 136 original plates, I contend only one clone of DCNcA in each well, had been removed aliquot of the supply in glicerol, that, in turn, they had served to initiate cultures in a new plate of 96 wells. In this stage, only clones in the positions E07 and F07 had been used (F08 was not analyzed to simplify the work). The 136 clones of the E07 position and the 136 clones of the F07 position had been reorganized in new plates that had again served as starting point for the assembly of a new matrix. This second matrix resulted of the mixture of all clones placed in one same line or one same column, in a total of 36 mixtures ( FIG. 3 , SEQ. ID NO:2). These mixtures had been used as source of DNA for amplification for PCR using the oligos T7 and 11. The result of the amplifications allowed to define the position of clones of DCNcA for KM+ (A* 12 or pLL30 and E*01 or pLL29), that they had been removed of the plates of the original library and had been used for the preparation of DNA and sequencing ( FIG. 4 , SEQ ID NO:3, SEQ. ID NO:4, SEQ. ID. NO5). FIG. 5 shows the alignment of 3 distinct amino acid sequences, corresponding the 3 isoforms of KM+ (one of them gotten through the sequencing of the protein and the others two, amino acid sequences deduced from the sequences of nucleotides of clones pLL29 and pLL30). Isoforms of the protein KM+, resultants of such forms of heterolog expression, anti-KM+, the selectivity of linking had kept the antigenicity front to the policlonal antibody the D-manose and to the trimanoside Man alfal-3 [Man alfal-6] Man, when tested front to a panel of sugars. In alive and in had been also capable to induce the migration of neutrophils vitro and to induce murines peritoneal cells to produce citocines of standard TH1.
OBJECTS OF THE INVENTION
[0011] More advantageously the invention understands pharmaceutical composition for imunomodulation holding lectin KM+.
[0012] Still more preferential the invention understands pharmaceutical composition holding lectin KM+.
[0013] Still more advantageously the invention understands insecticidal composition holding lectin KM+.
[0014] Preferential the invention understands medicine holding lectin KM+.
[0015] Advantageously the invention understands insecticide holding lectin KM+.
[0016] Still more preferential the invention understands the use of lectin KM+ in the imodulator medicine preparation.
[0017] Advantageously the invention understands the use of lectin KM+ in the medicine preparation to prevent or to deal with decurrent injuries chemical or physical aggressions.
[0018] More advantageously the invention understands the use of lectin KM+ in the anti-bacterial medicine preparation.
[0019] More preferential the invention understands the use of lectin KM+ in the anti-viral medicine preparation.
[0020] Still more preferential the invention understands the use of lectin KM+ in the anti-parasitic medicine preparation.
[0021] Advantageously the invention understands the use of lectin KM+ in the anti-fungal medicine preparation.
[0022] Still more advantageously the invention understands the use of lectin KM+ in the preparation of insecticide.
[0023] Still more advantageously the invention understands the use of lectin KM+ in the preparation of insecticidal composition.
[0024] Preferential the invention understands the use of lectin KM+ for recognition of manose.
[0025] More preferential the invention understands the use of lectin KM+ for purification of proteins contends manose.
[0026] Still more preferential the invention concerns to the method of expression of lectin KM+ being effected from DCNcA or genomic sequence or synthetic sequence for the native form.
[0027] Advantageously the invention mentions to it method of expression of lectin KM+ being effected in organism from DCNcA or genomic sequence or synthetic sequence in fusing with other proteins and peptides.
[0028] More advantageously the method of expression of lectin KM+ can be effected in organism from DCNcA or genomic sequence or synthetic sequence in fusing with peptides.
[0029] Preferential the method of expression of lectin KM+ can be effected in organism from DCNcA or genomic sequence or synthetic sequence in fusing with part of the original protein.
[0030] Still more advantageously the expression method holds organism understanding procariote or eucariote. Preferential the expression method holds procariote understanding bacteria.
[0031] More preferential the expression method holds bacteria understanding Escherichia coli.
[0032] Still more preferential the expression method holds bacteria understanding Caulobacter.
[0033] Preferential the expression method understands bacteria infectated with recombinant virus.
[0034] Advantageously the expression method holds eucariote understanding Saccharomyces.
[0035] More advantageously the expression method holds Saccharomyces understanding S. cerevisiae.
[0036] Preferential the expression method holds Schizosaccharomyces understanding the S. pombe.
[0037] More preferential the expression method holds eucariote understanding Pichia.
[0038] Still more preferential the expression method holds Pichia understanding the P. pastoral.
[0039] Advantageously the expression method holds Pichia understanding the methanolica P.
[0040] More advantageously the expression method holds eucariote understanding plants.
[0041] Still more advantageously the expression method understanding transgenics plants.
[0042] Preferential the expression method understands plants infectated with recombinant virus.
[0043] More preferential the expression method understands eucariote holding vegetal cells. Still more preferential the expression method holds eucariote understanding animal.
[0044] Advantageously the expression method holds animals understanding transgenics.
[0045] More advantageously the expression method holds animals understanding mammals.
[0046] Preferential the expression method understands the job of mammal cells.
[0047] More preferential the expression method holds animals understanding insects.
[0048] Still more preferential the expression method holds eucariote understanding animal transgenics and cells of mammals.
[0049] Advantageously the expression method holds eucariote understanding cells of insects.
[0050] Preferential the method of expression of lectin in And coli , can be effected from DCNcA subclonado in the vector pDEST14.
[0051] More preferential the vector of relative DNA understands the SEQ. ID. NO: 1-5.
[0052] Advantageously the DNA vector understands relative SEQ. ID. NO: 1-5 P F S G PK.
[0053] Advantageously the DNA vector understands relative SEQ. ID. NO: 1-5 K L P Y KN.
[0054] Advantageously the DNA vector understands SEQ. ID. NO: 1-5 A I G V H M to.
[0055] Still more advantageously the vector I contend the gene of the lectin understands the SEQ. ID NO: 2.
[0056] Preferential the recombinant organism understands the SEQ. ID. NO: 1-5.
[0057] More preferential the recombinant organism contains part of this protein.
[0058] Advantageously the DNA sequence can make pareament with the SEQ. ID NO: 2, can pairing, SEQ. ID NO: 1-5.
[0059] Preferential the sequence of nucleotides can codify one of the amino acid sequences of lectin KM+.
[0060] More preferential the lectin protein of Artocarpus integrifolia mentions the SEQ. ID NO: 1-5.
[0061] These and other objects of the present invention will become apparent to those skilled in the art from a review from the description provided below.
SUMMARY OF THE INVENTION
[0062] The present invention refers it pharmaceutical composition to heal or to prevent epithelial injuries understanding lectin KM+. Advantageously it understands the epithelial injuries holding the cutaneous injuries. Preferential the epithelial injuries understand the injuries of the cornea.
BRIEF DESCRIPTION OF THE INVENTION
[0063] The following figures are part of the present application:
[0064] FIG. 1 is an alignment of the amino acid sequences of lectins KM+ and jacaline, SEQ. ID NO: 1.
[0065] FIG. 2 is an amino acid sequence of the regions of KM+ chosen for the construction of oligonucleotides.
[0066] FIG. 3 is a schematical drawing of the matrix planned, consisting of three plates, SEQ. ID NO: 2.
[0067] FIG. 4 is a sequence of nucleotides of the present DCNcA of KM+ in the plasmid deduced amino acid pLL29, SEQ. ID NO: 3, SEQ. ID NO: 4, SEQ. ID NO: 5.
[0068] FIG. 5 is an alignment of the amino acid sequences deduced from the DCNcAs of the plasmids pLL29 and pLL30 and the gotten one from chemical analyses of the protein and depositing in data base (Pink et al., 1999).
[0069] FIG. 6 is a graphical representation of a resultant membrane of the Western blot showing corresponding bands to the recombinant proteins KM+ and produced Gst-km+ in And coli , and protein KM+ produced in S. cerevisiae.
[0070] FIG. 7 is a graphical that compares the activity of linking with the glycoprotein (peroxidase) exerted by lectin KM+ derived from jaca seeds and by lectin KM+ gotten from the expression in heterologic system (lectin recombinant KM+).
[0071] FIG. 8 is a graphical that shows the specific inhibition for monossacaride D-manose of the linking of KM+ of recombinant plant or KM+ to the glycoprotein (peroxidase).
[0072] FIG. 9 are photographs of decurrent injuries of burnings in the back of rats submitted to the topic application of lectin KM+ or only of the vehicle.
DETAILED DESCRIPTION OF THE INVENTION
[0073] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
[0074] Relative ID to FIGS. 1 the 9 . Advantageously the lectin protein of Artocarpus integrifolia mentions the Seqs to it. Relative ID to cited FIGS. 1 the 9 and any of isoforms. Preferential the lectin protein of Artocarpus integrifolia mentions the Seqs to it. Relative ID to cited FIGS. 1 the 9 and any of isoforms. More preferential the method of expression of lectin KM+ in S. cerevisiae , can be effected from DCNcA subclonado in the vector pYES-DEST52. Advantageously the plasmid of expression can contain as inserto the DNA sequence that codifies for lectin protein KM+ of Artocarpus integrifolia . More advantageously the plasmid of expression can use the relative information to the gene of lectin KM+ of Artocarpus integrifolia . Observing itself that lectin KM+, through the property to induce macrophages to produce I1-12 and to exert protective effect against infection for L. major and knowing itself that the brasiliensis resistance to the infection for Paracoccidioides depends on an efficient Th1 reply, evaluated the effect of the inoculation of KM+ in mice that would be defied with leavenings of P. brasiliensis. Groups of animals had been injected with KM+, associate or not its cell free antigen (CFA) proceeding from isolated Pb 18 of P. brasiliensis. Animals of another group had been injected with alone CFA and a group control received PBS.
[0075] The animals intravenously had been infectated with isolated leavenings of virulent of P. brasiliensis and, in the following period, monitored how much the diverse parameters, including the proliferactive reply of esplenic cells, recovery of formator units of colonies (CFU) in the fabric pulmonary and histopatologye of pulmonary injuries. The depression of proliferactive, proper reply of the infection, was reverted in the animals daily pay-inoculated with KM+. The recovery of formator units of colonies in the fabric pulmonary was carried through and was verified that the proportionate amount of colonies for the lungs of the animals daily pay-inoculated with KM+, was very inferior to the gotten one in the lungs of the animals that had not received the lectin. The pulmonary histopatologye showed that the mice daily pay-inoculated with KM+ showed size and significantly lesser number of granulomes how much to not treated. Such results indicate that KM+ intervenes positively with the course of the infection for P. brasiliensi , and that such imunomodulatory effect if makes independently of any process of immunization with fungic antigen. Lectin KM+ was incorporated in ointment on the basis of petroleum jelly, added or not of acid linoleic and also in formularization the base of propilenoglicol. The incorporation can be made in conventional dermatological bases (remarcably emulsions water in oil, hydrophilic and gel emulsions oil in water, ointment hidrofobics, ointment), as well as in elaborated systems of release more, contends or not promotional substances of the cutaneous absorption (remarcably propilenoglicol, acid oleic, derivatives of pirrolidona, etanol, dimetilsulfoxido, and fosfolipides) as multiple emulsions, micron and nanoemulsion or emulsions sucromicas, lipossomes, transferssomes, ethossomes and other types of vesicles, nanossomes, beyond other micron and nanoparticulados systems, as micron and nanocapsules, micron and nanoespheres and vehicles I contend ceramides, liquid, complex crystals of inclusion as that one with ciclodextrines, supersaturated solutions, formularizations with macro-molecules capable to form gel and films. To improve still more the penetration they could be gotten pro-pharmaceuticals of the substance (as ester remarcably), leaving it with a rocking hidro and adjusted lipophilic more for the penetration in the followed corneo stratum of conversion in the skin for the free pharmaceutical. All these pharmaceutical forms and systems of release of the pharmaceutical can be placed in devices that still more improve the performance of the substance for determined required action, as, remarcably, transdermic powderject (it shoots particles through the corneo stratum for the layers deepest of the skin for supersonic waves of gas shock helium) intraject (uses gas source compressed nitrogen to project doses of formularization through the skin for the fabric subcutaneous), microneedles, iontoforese, eletroporaction and high voltage (100 the 1000 V), sonoforese. The acute influx of inflammatory cells for KM+ based the hypothesis of that the lectin could have anti-microbian action to the being applied in injured cutaneous surfaces that, as well known, correspond the important door of entrance of patogens. The secondary infection corresponds the cause most frequent of death of patients with extensive losses of continuity of the cutaneous surface, as the ones that occur in great burnt. To test the hypothesis of, that the influx of neutrophils provoked by the lectin could diminish the infection incidence, rats had been submitted the thermal aggression in the dorsal region and topically treated with ointment I contend KM+.
[0076] Surprising the action of KM+ if it made to after notice since few hours the application of the ointment one, and it was not related with the combat to the secondary infections, but yes to a precocious regeneration of the fabric injured. The animals dealt with KM+ differentiated themselves of the not treat ones (to which the vehicle was applied only) for the absence of necro-hemorrhagic areas, or deep injuries that they displayed weaved muscular. In contrast regeneration if made quickly, the edges of the injuries was little salient, was come close quickly, having precocious cicatrizaction of the wound, manifest for local reepitelizaction and ressurgiment of pilificaction. Many experiments, of varied characteristics had been repeated, with superficial or deep injuries, different burnings of ample or small diameters, times of exposition to the heat, use of dry or humid heat. In all the experimental circumstances the animals if had benefited of the local application of KM+ In FIG. 9 are the photographs of the dorsal region of two groups of animals, 5 treated topically with lectin KM+ (3 applications), and treated others 5 only with the vehicle (3 applications). All had suffered to thermal injury in the back 24 hours before the photo. The rats dealt with KM+ (inferior photograph series) had had the fabric preserved, while the ones that had received only the vehicle (superior photograph series) present local necro-hemorrhagic injuries. The dramatically beneficial action of the application of KM+ in the fabrics is clear that had suffered thermal aggression. | The invention deals with a pharmaceutical composition comprising lectin KM+ to prevent and heal epithelial wounds. The invention also comprises the use of lectin KM+, obtained from the plant ( Artocarpus integrifolia ) or recombinant (expression heterologue) to prepare medicaments. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 14/054,333, filed Oct. 15, 2013, which is a continuation of U.S. patent application Ser. No. 13/299,661, filed Nov. 18, 2011, which claims the benefit under 35 U.S.C. §119 of Korean Application No. 10-2010-0115160, filed Nov. 18, 2010, which are hereby incorporated by reference in their entirety.
BACKGROUND
[0002] The present disclosure generally relates to a spindle motor.
[0003] A spindle motor performs a function of rotating a disk to enable an optical pickup which linearly reciprocates in an optical disk drive ODD and a hard disk to read a large amount of data recorded on the disk. The ODDs have been recently developed to stably rotate an optical disk at a high speed.
[0004] The ODD includes a spindle motor for rotating an optical disk at a high speed, an optical pickup module for reading out data from a disk rotating at a high speed or recording the data on the disk, and a stepping motor for driving the optical pickup module.
[0005] The spindle motor rotating the optical disk at a high speed includes a bearing rotationally supporting a rotation shaft, a bearing housing accommodating the bearing, a stator secured at a periphery of the bearing housing, a rotor rotationally accommodated on the bearing, a base plate fixing the bearing housing and a circuit substrate arranged at an upper surface of the base plate.
[0006] A gap is formed between an upper surface of the base plate and the stator according to a conventional spindle motor to disadvantageously introduce foreign objects. In order to reduce the gap formed between the stator and the upper surface of the base plate, the circuit substrate arranged on the upper surface of the base plate is unnecessarily extended to a bottom surface of the stator. If the circuit substrate is extended to between the stator and the base plate, inflow of foreign objects into the base plate and the stator may be reduced to a certain degree. However, a problem occurs in which an area of the high-priced circuit substrate disadvantageously increases to increase a manufacturing cost of the spindle motor.
BRIEF SUMMARY
[0007] Exemplary embodiments of the present disclosure provide a spindle motor configured to reduce a manufacturing cost by dispensing with unnecessary extension of a circuit substrate into between a stator and a base plate and by preventing foreign objects from entering the stator and the base plate.
[0008] In one general aspect of the present disclosure, there is provided a spindle motor, comprising: a base plate; a PCB on the base plate; a bearing assembly arranged on the base plate; a stator coupled to a periphery of the bearing assembly; a rotor rotationally coupled to the bearing assembly, the rotor including a yoke and a magnet; and a rotation shaft rotationally coupled to the bearing assembly, wherein the base plate includes a planar portion and a protruding portion arranged along with a periphery of the yoke, the protruding portion being apart from the yoke, wherein the base plate may be partially covered with the PCB in a region where the stator is arranged, and wherein a height from the planar portion to an upper surface of the protruding portion may be smaller than a height from the planar portion to a lower surface of the periphery of the yoke.
[0009] In some exemplary of the present invention, the PCB may include an exposure unit exposing a part of the base plate opposite to the stator, and the protruding portion prevents foreign objects from entering to the exposure unit.
[0010] In some exemplary of the present invention, the base plate may include a first through hole to be coupled to the bearing assembly, and the PCB includes a second through hole formed at a position corresponding to that of the first through hole and partially opened toward the protruding portion.
[0011] In some exemplary of the present invention, the protruding portion may include a shape of a curved line when viewed in a top plane.
[0012] In some exemplary of the present invention, the protruding portion may have the same curvature as that of a core of the stator.
[0013] In some exemplary of the present invention, the height from the planar portion to the upper surface of the protruding portion may be the same as thickness of the PCB.
[0014] In some exemplary of the present invention, the protruding portion may protrude with a right angle relative to the planar portion.
[0015] In some exemplary of the present invention, the height from the planar portion to the upper surface of the protruding portion may be higher than the thickness of the PCB.
[0016] In some exemplary of the present invention, the protruding portion may protrude with an obtuse angle relative to the planar portion.
[0017] In some exemplary of the present invention, the protruding portion may protrude with an acute angle relative to the planar portion.
[0018] In some exemplary of the present invention, the protruding portion may be integrally formed with the planar portion.
[0019] In some exemplary of the present invention, the protruding portion may be integrally formed with the planar portion by bending a part of the base plate.
[0020] In some exemplary of the present invention, the protruding portion may include a semi-circular shape when viewed in a top plane.
[0021] In some exemplary of the present invention, the bearing assembly may include a bearing housing and a bearing inserted into the bearing housing, the stator may include a core including radially formed core pieces and a coil wound on the core pieces, and the rotor may include the magnet opposite to the core pieces and the yoke fixing the magnet and coupled to the rotation shaft inserted into the bearing.
[0022] In some exemplary of the present invention, the PCB may be formed with a through hole through which the bearing assembly passes, and a diameter of the through hole may be larger than that of the bearing assembly, and the through hole may be partially opened.
[0023] In another general aspect of the present disclosure, there is provided a spindle motor, comprising: a base plate; a PCB on the base plate; a bearing assembly arranged on the base plate; a stator coupled to a periphery of the bearing assembly; a rotor rotationally coupled to the bearing assembly, the rotor including a yoke and a magnet; and a rotation shaft rotationally coupled to the bearing assembly, wherein the yoke may include an upper plate and a lateral plate, wherein the base plate may include a planar portion and a protruding portion arranged along with the lateral plate of the yoke, and wherein the protruding portion may be configured to have a gap between the protruding portion and a lower surface of the lateral plate of the yoke.
[0024] In some exemplary of the present invention, the PCB may be partially arranged on the base plate in a region where the rotor is arranged.
[0025] In some exemplary of the present invention, the base plate may include a first through hole to be coupled to the bearing assembly, and the PCB may include a second through hole formed at a position corresponding to that of the first through hole and partially opened toward the protruding portion.
[0026] In some exemplary of the present invention, the protruding portion may include a shape of a curved line when viewed in a top plane.
[0027] In some exemplary of the present invention, the protruding portion may have the same curvature as that of a core of the stator.
[0028] In some exemplary of the present invention, a height from the planar portion to an upper surface of the protruding portion may be the same as thickness of the PCB.
[0029] In some exemplary of the present invention, a height from the planar portion to an upper surface of the protruding portion may be higher than the thickness of the PCB.
[0030] In some exemplary of the present invention, the protruding portion may protrude with an obtuse angle relative to the planar portion.
[0031] In some exemplary of the present invention, the protruding portion may protrude with an acute angle relative to the planar portion.
[0032] In some exemplary of the present invention, the protruding portion may be integrally formed with the planar portion.
[0033] In some exemplary of the present invention, the protruding portion may be integrally formed with the planar portion by bending a part of the base plate.
[0034] In some exemplary of the present invention, the protruding portion may include a semi-circular shape when viewed in a top plane.
[0035] In some exemplary of the present invention, the bearing assembly may include a bearing housing and a bearing inserted into the bearing housing, the stator may include a core including radially formed core pieces and a coil wound on the core pieces, and the rotor may include the magnet opposite to the core pieces and the yoke fixing the magnet and coupled to the rotation shaft inserted into the bearing.
[0036] In some exemplary of the present invention, the PCB may be formed with a through hole through which the bearing assembly passes, and a diameter of the through hole is larger than that of the bearing assembly, and the through hole may be partially opened.
[0037] The spindle motor according to the exemplary embodiments of the present disclosure has an advantageous effect in that an exposure unit is formed at a part of a PCB interposed between a base plate and a core of a stator to reduce a manufacturing cost of the PCB, and foreign objects introduced through the exposure unit is prevented by a foreign object inflow prevention fence formed at the base plate to avoid the spindle motor from being polluted by the foreign objects.
[0038] Additional advantages, objects, and features of the disclosure will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the disclosure. The objectives and other advantages of the disclosure may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
[0039] It is to be understood that both the foregoing general description and the following detailed description of the present disclosure are exemplary and explanatory and are intended to provide further explanation of the disclosure as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] Accompanying drawings are included to provide a further understanding of arrangements and embodiments of the present disclosure and are incorporated in and constitute a part of this application. In the following drawings, like reference numerals refer to like elements and wherein:
[0041] FIG. 1 is a perspective view of a spindle motor according to an exemplary embodiment of the present disclosure;
[0042] FIG. 2 is a cross-sectional view taken along line 1 - 1 ′ of FIG. 1 ;
[0043] FIG. 3 is a plane view illustrating a spindle motor of FIG. 1 removed of a rotation shaft and a rotor;
[0044] FIG. 4 is a partially enlarged perspective view illustrating a spindle motor of FIG. 3 removed of a stator; and
[0045] FIG. 5 is a lateral view of FIG. 1 .
DETAILED DESCRIPTION
[0046] Hereinafter, exemplary embodiments of the present disclosure are described in detail with reference to the accompanying drawings. In the drawings, sizes or shapes of constituent elements may be exaggerated for clarity and convenience.
[0047] Particular terms may be defined to describe the disclosure in the best mode as known by the inventors. Accordingly, the meaning of specific terms or words used in the specification and the claims should not be limited to the literal or commonly employed sense, but should be construed in accordance with the spirit and scope of the disclosure. The definitions of these terms therefore may be determined based on the contents throughout the specification. The meaning will be clear from the context of the description. Like numbers refer to like elements throughout, and explanations that duplicate one another will be omitted.
[0048] As may be used herein, the terms “substantially” and “approximately” provide an industry-accepted tolerance for its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to ten percent and corresponds to, but is not limited to, component values, angles, et cetera.
[0049] Any reference in this specification to “one embodiment,” “an embodiment,” “exemplary embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to affect such feature, structure, or characteristic in connection with others of the embodiments.
[0050] FIG. 1 is a perspective view of a spindle motor according to an exemplary embodiment of the present disclosure, FIG. 2 is a cross-sectional view taken along line 1 - 1 ′ of FIG. 1 , FIG. 3 is a plane view illustrating a spindle motor of FIG. 1 removed of a rotation shaft and a rotor, FIG. 4 is a partially enlarged perspective view illustrating a spindle motor of FIG. 3 removed of a stator, and FIG. 5 is a lateral view of FIG. 1 .
[0051] Referring to FIGS. 1 to 5 , a spindle motor 800 includes a bearing assembly 100 , a stator 200 , a rotation shaft 300 , a rotor 400 , a base plate 500 and a PCB Printed Circuit Board, 700 . In addition, the spindle motor 800 may further include a clamp 600 .
[0052] The bearing assembly 100 includes a bearing housing 110 and a bearing 120 . The bearing housing 110 takes a shape of a hollow hole-formed cylinder, for example, and the bearing housing 110 is formed at an upper corner with a staircase sill 115 for securing a core described later. The bearing housing 110 is protruded at a rear surface with a coupling lug 117 for being coupled with the base plate 500 , described later.
[0053] The bearing housing 110 is arranged at a bottom surface with a support plate 119 for supporting a bottom end of the rotation shaft 300 , described later, and a portion contacting a bottom end of the rotation shaft 300 in the support plate 119 is formed with a thrust bearing 119 a.
[0054] The bearing 120 takes a shape of a cylinder inserted into the bearing housing 110 , and is formed with a rotation shaft hole for being coupled with the rotation shaft. In the exemplary embodiment of the present disclosure, the bearing 120 may include an oil sintered impregnation bearing.
[0055] The stator 200 includes a core 210 and a coil 220 . The core 210 is formed by stacking a plurality of iron pieces each having an opening, and secured to the staircase sill 115 of the bearing housing 100 . In the exemplary embodiment of the present disclosure, the core 210 includes core units 212 , where the core units 212 are formed by being radially protruded, and the core 210 including the core units 212 takes a shape of a disk when viewed in a top plane.
[0056] In the exemplary embodiment of the present disclosure, a part of the core 210 including the core units 212 may be arranged to protrude from an edge of the base plate 500 . The coil 220 is wound on the core unit 212 formed at the core 210 .
[0057] The rotation shaft 300 is inserted into the rotation shaft hole of the bearing 120 at the bearing assembly 100 , and a bottom end of the rotation shaft 300 is brought into contact with the thrust bearing 119 a supported by the support plate 119 .
[0058] The rotor 400 includes a yoke 410 and a magnet 420 . In addition, the rotor 400 may further include a suction magnet 430 . The yoke 410 may include a yoke upper plate 412 and a yoke lateral plate 414 .
[0059] The yoke upper plate 412 , when viewed from a top plane, takes a shape of a disk, and is centrally formed with a cylindrically shaped yoke burring unit 413 towards an upper surface of the yoke upper plate 412 . The yoke burring unit 413 is press-fitted into the rotation shaft 300 .
[0060] The yoke lateral plate 414 is downwardly extended from the yoke upper plate 412 and a void is formed inside the yoke 410 by the yoke lateral plate 414 and the yoke upper plate 412 .
[0061] The magnet 420 is formed along an inner lateral surface of the yoke lateral plate 414 , and a rotational force is generated on the yoke 410 and the rotation shaft 300 by attractive force and repulsive force generated a magnetic field generated by the coil 220 wound on the core unit 212 of the core 210 and a magnetic field generated by the magnet 420 . The yoke upper plate 412 of the yoke 410 is arranged with a clamp 600 for chucking an optical disk.
[0062] Meantime, a suction magnet 430 may be arranged at any one place of an inner lateral surface of the yoke upper plate 412 and an upper surface of the core 210 opposite to the inner lateral surface of the yoke upper plate 412 .
[0063] In the exemplary embodiment of the present disclosure, the suction magnet 430 may be arranged at the inner lateral surface of the yoke upper plate 412 , for example, and the suction magnet 430 arranged at the inner lateral surface pulls the core 210 using the magnetic force to stably rotate the rotor 400 .
[0064] Referring to FIGS. 2 , 3 and 4 again, the base plate 500 is formed by processing a metal plate. The base plate 500 is formed with a through hole 502 corresponding to the hollow hole of the bearing housing 110 at the bearing assembly 100 , as shown in FIG. 2 .
[0065] The base plate 500 is formed with a lug 510 formed in a shape corresponding to the core 210 of the stator 200 , and the lug 510 may take a semi-disk semi-circular shape when viewed in a top plane. Thus, foreign objects can be initially prevented by the lug 510 from entering an interior of the spindle motor through a bottom surface of the core 210 .
[0066] The PCB 700 is arranged at an upper surface of the base plate 500 , and is mounted with a variety of circuit elements, where the PCB 700 is electrically connected to the coil 220 which is a constituent element of the stator 200 . The PCB 700 is formed with a through hole 505 for preventing an interference with the bearing housing 110 . Size of the through hole 505 formed at the PCB 700 is larger than that of a through hole 502 formed at the base plate 505 . The through hole 505 of the PCB 700 is partially opened and the opened portion of the through hole 505 may be formed with a curvature.
[0067] Referring to FIGS. 2 and 5 , a bottom surface of the core 210 coupled to the bearing housing 110 of the bearing assembly 100 coupled to the base plate 500 is discrete from an upper surface of the base plate 500 at a predetermined gap, where various foreign objects such as dust, fine particles, oily dust and the like can be introduced into the base plate 500 and the bottom surface of the core 210 , and the foreign objects can be attached to the core 210 , the coil 220 , the bearing and the magnet 420 , and life of the spindle motor 800 can be greatly reduced by the foreign objects attached thereto.
[0068] In order to prevent the foreign objects from introducing into the gap between the upper surface of the base plate 500 and the bottom surface of the core 210 , a partial area of the PCB 700 may be extended to be arranged on the lug 510 of the base plate 500 .
[0069] In a case the PCB 700 covers the semi-disk lug 510 of the base plate 500 , the gap between the upper surface of the base plate 500 and the bottom surface of the core 210 is reduced as much as thickness of the PCB 700 to decrease inflow of the foreign objects.
[0070] However, in a case the high-priced PCB 700 is unnecessarily extended to cover the lug 510 of the base plate 500 , a manufacturing cost of the spindle motor 800 is inevitably increased.
[0071] In the exemplary embodiment of the present disclosure, the PCB 700 is formed with an exposure unit 710 that exposes the semi-disk lug 510 of the base plate 500 as illustrated in FIG. 5 . The closed through hole 505 formed at the PCB 700 is opened by the exposure unit 710 .
[0072] In the exemplary embodiment of the present disclosure, the frequently used “exposure unit” is defined by a portion exposing the base plate 500 that is formed by removing a part corresponding to a part opposite to the core 210 in the PCB 700 arranged on the base plate 500 .
[0073] A portion corresponding to the semi-disk lug 510 is formed the by exposure unit with a void space not formed with the PCB 700 . In a case the exposure unit 710 exposing a part of the semi-disk shaped lug 510 of the base plate opposite to the core 210 is formed on the PCB 700 , an area of the PCB 700 is reduced whereby a manufacturing cost of the PCB 700 can be decreased but the foreign objects can be introduced in the spindle motor through the exposure unit 710 .
[0074] In the exemplary embodiment of the present disclosure, in order to prevent the foreign objects from entering through the exposure unit 710 of the PCB 700 formed between the upper surface of the base plate 500 and the bottom surface of the core of the stator 200 , a foreign object inflow prevention fence 520 is formed at the base plate 500 .
[0075] The foreign object inflow prevention fence 520 is formed along an edge of the semi-disk shaped lug 510 and takes a shape of curved fence. A distal end of the curvature-shaped foreign object inflow prevention fence 520 is brought into contact with a distal end of the PCB 700 formed by the exposure unit 710 , and the other distal end corresponding to the distal end of the foreign object inflow prevention fence 520 is brought into contact with the other distal end corresponding to the distal end of the PCB 700 formed by the exposure unit 710 .
[0076] In the exemplary embodiment of the present disclosure, a height of the foreign object inflow prevention fence 520 may be substantially same as thickness of the PCB, for example. Alternatively, it should be apparent that the height of the foreign object inflow prevention fence 520 is greater than the thickness of the PCB.
[0077] The foreign object inflow prevention fence 520 may be erected at a right angle relative to the base plate 500 . Alternatively, the foreign object inflow prevention fence 520 may be erected at an obtuse angle or an acute angle relative to the base plate 500 .
[0078] In the exemplary embodiment of the present disclosure, the foreign object inflow prevention fence 520 may be formed by bending an edge of the semi-circular lug 510 of the base plate 500 to a direction facing the core 210 . In the exemplary embodiment of the present disclosure, the foreign object inflow prevention fence 520 formed by bending the edge of the semi-circular lug 510 of the base plate 500 is formed in the shape of a curved plate.
[0079] Although a gap between the base plate 500 and the bottom surface of the core 210 of the stator 200 may increase by the PCB 700 formed with the exposure unit 710 for reducing the manufacturing cost, the foreign objects can be blocked by the foreign object inflow prevention fence 520 formed at the base plate 500 through the formation of the foreign object inflow prevention fence 520 formed at the base plate 500 .
[0080] In the exemplary embodiment of the present disclosure, both distal ends of the foreign object inflow prevention fence 520 are brought into contact with the PCB 700 , whereby inflow of foreign objects are prevented from entering a space formed between the distal end of the foreign object inflow prevention fence 520 and the PCB 700 .
[0081] Although the exemplary embodiments of the present disclosure have illustrated and explained a structure in which a part of the base plate 500 is bent to form the foreign object inflow prevention fence 520 , it should be apparent that the foreign object inflow prevention fence is alternatively formed by a synthetic resin material hardened along an upper edge of the lug 510 of the base plate 500 in a strip shape and coated on the base plate 500 using a dispenser. At this time, it should be apparent that the synthetic resin material has elasticity free from generating a static electricity, such that even if the synthetic resin material is brought into contact with the rotating yoke 410 , no noise and damage can be generated.
[0082] Meanwhile, in order to prevent foreign objects such as dust introduced through the foreign object inflow prevention fence 520 from attaching to essential parts of the spindle motor despite the formation of the foreign object inflow prevention fence 520 , a foreign object attachment member may be arranged at a rear surface of the foreign object inflow prevention fence to which foreign objects introduced into the foreign object inflow prevention fence are attached. The foreign object attachment member may include an adhesive material having viscosity to which foreign objects having passed the foreign object inflow prevention fence 520 are attached.
[0083] Meanwhile, the foreign object inflow prevention fence 520 preventing inflow of foreign objects may be manufactured with a synthetic resin material, and the foreign object inflow prevention fence 520 manufactured with the synthetic resin material may be attached to the base plate by an adhesive.
[0084] As apparent from the foregoing, the spindle motor according to the exemplary embodiments of the present disclosure has an industrial applicability in that an exposure unit is formed at a part of a PCB interposed between a base plate and a core of a stator to reduce a manufacturing cost of the PCB, and foreign objects introduced through the exposure unit is prevented by a foreign object inflow prevention fence formed at the base plate to avoid the spindle motor from being polluted by the foreign objects.
[0085] Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this invention. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawing and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art. | A spindle motor is provided, the motor comprising: a base plate, a PCB on the base plate, a bearing assembly arranged on the base plate, a stator coupled to a periphery of the bearing assembly, a rotor rotationally coupled to the bearing assembly, the rotor including a yoke and a magnet, and a rotation shaft rotationally coupled to the bearing assembly. The base plate includes a planar portion and a protruding portion arranged along with a periphery of the yoke, the protruding portion being apart from the yoke. The base plate is partially covered with the PCB in a region where the stator is arranged. And, a height from the planar portion to an upper surface of the protruding portion is smaller than a height from the planar portion to a lower surface of the periphery of the yoke. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to a vehicle parking apparatus with a lift platform which can be brought to parking boxes provided in different stories of a multi-story car park and also a method for its operation.
A variety of parking systems of this kind are known (DE-PS 11 28 966, GB-PS 11 88 930, DE-AS 11 94 122, CH-PS 520, 852, EP 0 501 935 A1, DE-OS 28 23 585). They have the following disadvantages:
They require a direct control and are dependent on monitoring by personnel stationed in the lift itself.
They are not suited for computerized external control.
They are very complex and have thus not been used in practice.
The recycling of the pallets has not been satisfactorily solved.
SUMMARY OF THE INVENTION
In contrast, an object underlying the present invention is to provide a parking system of the initially named kind which is of low complexity, which is similar to manufacture and operate and which is suitable, in particular when used in a public multi-story car park, both for the use with a centralized and computerized external control and also for self-service operation.
In order to satisfy this object there is provided, in accordance with the present invention, a vehicle parking system comprising at least one lift platform which can be brought to parking boxes provided in rows in different stories of a multi-story car park and on which at least one movable vehicle carrying pallet can be arranged which is formed by two box-like wheel supporting beams which extend in the direction of travel and which have a length corresponding to the wheel base of the vehicle types to be accommodated and also a lateral spacing corresponding to the track widths of the vehicles to be accommodated, with the wheel supporting beams being in the form of an inverse U with outwardly directed angled portions at the lower longitudinal edges and having box section floors preferably consisting of a plurality of plates which connect the lower longitudinal edges as well as means for longitudinal rolling at the front and rear ends and, at the front and at the rear, in each case at least one, and at the front preferably two cross-beams which connect the wheel supporting beams together and are secured on the wheel supporting beams at the top, of which the front cross-beam or the front cross-beams is/are formed as an abutment for the front wheels of the vehicle and the rear cross-beam is formed as an abutment for the rear wheels of the vehicle type having the longest wheel base, and wherein the lift platform carries friction wheels and at least one pallet drive means having a shifting beam carrying the friction wheels by means of which, when the parking box or the loading or unloading spaces on the one side and the lift platform on the other side are aligned with one another, vehicle carrying pallets standing empty on the lift platform can be displaced into the parking box or into the unloading space and vehicle carrying pallets which are present in the parking box or in the loading space can be displaced onto the lift platform.
Accordingly the pallet structure comprises two especially shaped, parallel, wheel supporting beams of thin-walled sheet metal which have a downwardly open U-section with two lower angled portions as runners and also a plurality of connection plates between the latter. The beam which is thus of box-like shape is torsionally stiff and its upper surface is also resistant to denting and avoids the instability which arises with the known open trough shape with a low wall thickness through lateral buckling of the side walls under load.
The wheel supporting beams have a length which only covers the longest wheel base of the vehicles to be accommodated and have an individual width and a spacing from one another which only just accommodates the tread contact patches of the tires of vehicles to be accommodated with the largest and smallest track widths which results, apart from material saving, also in favorable loading conditions through the tires of the heaviest vehicles.
The transverse beams which connect these wheel supporting beams simultaneously serve to indicate to the driver that he has reached the desired position and--after stopping--ensure a reliable retention of the vehicles on their vehicle pallets during their displacement, and indeed even when the handbrake of the parked vehicle has not been engaged.
Through appropriate arrangement the roller a high load carrying ability is achieved even with a relatively thin wheel axle, which also contributes substantially to a light-weight arrangement.
Another particularly expedient aspect of the invention relates to the way in which the load peaks generated by the driving of the front and rear wheels of the vehicle over the entire length of the wheel supporting beams are directly picked up by the support rollers of fixed location. These load peaks are not themselves repeated during the parking movements and the parking itself since the wheel loading points on the wheel supporting beams remain unchanged in the direct vicinity of the pallet support rollers. In this way a considerable reinforcement of the carrying beam structure which would otherwise be necessary, or alternatively a plurality of carrying rollers on all pallets, is avoided. The thereby obtainable material and manufacturing cost savings for the vehicle carrying pallets of the invention are about 50% in comparison to the pallets of known parking systems, which leads to a considerable saving having regard to the fact that there are normally over 100 pallets for each individual vehicle parking system. Since the support rollers are only provided in the loading and unloading spaces the cost and effort of providing them is comparatively low. In a further embodiment of this invention the inner flanks of the inverted U-shaped carriageway carriers are simultaneously used as drive surfaces for the engagement of the frictional wheels.
The present invention further contemplates to provide a central auxiliary rail of the same length as known per se on the vehicle carrying pallet for its transport.
The present invention further advantageously provides that the drive of the vehicle carrying pallets during the acceleration phase automatically enhances the contact pressure of the frictional wheels against the oppositely disposed drive surface during driving, with a resulting reduction of the pressure during braking and in the opposite direction of travel being unproblematic because, in this case, the vehicle carrying pallets have already been accelerated so that they only need to be held against travelling further and braked until they reach their end position.
For the interchanging of empty and full vehicle carrying pallets at the individual parking boxes the present invention employs a design which avoids the use of at least one parking box as an exchange buffer station with longer travelling and turn-around times.
Another aspect of the invention arranges the guide beams to ensure that broad track vehicles and their wheels can be effortlessly aligned and parked even by self-parkers without breakdown or danger on the wheel supporting beams which, in accordance with the invention, are narrow and which each only correspond to the lateral wheel tracks of the vehicles to be accommodated within their outer edges.
The same is provided with reference to the alignment of narrow track vehicles by using liftable inner guide beams. Moreover the plates connected to the guide beams cover the opening which otherwise exists between the wheel supporting beams of the vehicle pallet which has been prepared to accept the vehicle, so that even with extreme driving errors of the incoming driver the dropping of a wheel into the inner opening is prevented.
The prevention or hindering of a loaded pallet being moved away due to firm contact of a tire on one of the compulsorily tracking members is avoided in that, before moving the pallet away, the outer guides are freed and the inner guides are withdrawn. In this manner an overloading or inability of the friction roller drive to function is prevented.
A further advantage provided by the invention is that the friction wheels are brought reliably into force-locked engagement with the drive surfaces associated with them, so that an effective and high acceleration is ensured at the start of the movement of the vehicle carrying pallets as well as reduced wear of the friction wheels.
The above-described features of the present invention and others contribute to the vehicle carrying pallets themselves being of an extremely simple, light-weight but nevertheless adequately stable construction since as many construction elements as possible are kept away from the vehicle carrying pallets and are arranged at another position where they only have to be present once or a few times but not however a hundred times.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of a vehicle carrying pallet of a vehicle parking system made in accordance with the invention,
FIG. 2 is a schematic section taken on line II--II in FIG. 1,
FIG. 3 is a schematic section taken on line III--III in FIG. 1,
FIG. 4 is a schematic side view of FIG. 1,
FIG. 5 is a partial view, corresponding to FIG. 4, of a further embodiment of the front part of the vehicle pallet of FIG. 4,
FIG. 6 is a schematic plan view of a parking box containing a vehicle carrying pallet of a vehicle parking system made in accordance with the invention at the end of the loading procedure or at the start of an unloading procedure,
FIG. 7 is a schematic plan view of a lift platform of a vehicle parking system in accordance with the invention with the shifting beam located in the rest position and with a vehicle carrying pallet indicated in broken lines,
FIG. 8 is a schematic plan view analogous to FIG. 6 of a further embodiment of the invention,
FIG. 9 is a schematic plan view analogous to FIG. 7 of the embodiment of FIG. 8,
FIG. 10 is an enlarged schematic plan view of a part of a parking box and of a lift platform, with the vehicle carrying pallet located in its end position in the parking box and with engagement of the drive means with the vehicle carrying pallet,
FIG. 11 is a somewhat enlarged sectional view in accordance with line XI--XI in FIG. 10,
FIG. 12 is an analogous schematic plan view to that of FIG. 10 of a further embodiment of the invention,
FIG. 13 is a somewhat enlarged schematic sectional view in accordance with line XIII--XIII in FIG. 12,
FIG. 14 is a schematic side view of a lift platform arranged in a lift shaft with a vehicle carrying pallet arranged thereon and in turn carrying a vehicle,
FIG. 15 is a schematic sectional view in accordance with the line XV--XV in FIG. 14,
FIG. 16 is a schematic side view of a vehicle carrying pallet carrying a vehicle in the vehicle loading space,
FIG. 17 is a corresponding side view of the vehicle carrying pallet in the unloading space,
FIG. 18 is a schematic cross-sectional view of the loading space with a vehicle carrying pallet having vehicle wheel tracking elements located therein,
FIG. 19 is a plan view of FIG. 18,
FIG. 20 is an enlarged side view of a buffer provided at the front end of the vehicle carrying pallet in the loading space, and
FIG. 21 is a schematic front view of FIG. 20 in the direction of the arrow XXI in FIG. 20.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In all figures the same reference numerals designate corresponding components.
In accordance with FIGS. 1 to 4 a vehicle carrying pallet 13 of a vehicle parking apparatus in accordance with the invention comprises two wheel supporting beams 14 of thin-walled steel in the shape of an inverted U which are arranged laterally spaced apart parallel to one another with outwardly directed, horizontal, angled portions 15 located at the lower margins of the side flanks of the wheel supporting beams 14. At the front the two wheel supporting beams 14 are connected by two cross-beams 18, 19 which are spaced apart and are secured to the upper side of the wheel supporting beams 14, whereas at the rear end one cross-beam 20 is secured to the upper side of the wheel supporting beams 14 and connects them together. In this manner a frame arises which is rectangular in plan view (FIG. 1).
In accordance with FIG. 3 the lateral spacing and width of the wheel supporting beams 14 is so selected that both the front vehicle wheels 21 of wide track vehicles and also the front wheels 21' of narrow track vehicles find a place thereon, i.e. fit thereon.
Stiffening plates 16 are secured to the lower side of the wheel supporting beams 14 at specific intervals in the longitudinal direction in accordance with FIGS. 1, 3 and 4 and function as a whole to provide a box section which can be seen from FIG. 3 which is particularly resistant to denting, buckling and torsion.
At the front and at the rear roller arrangements are provided at the four corners of the vehicle carrying pallet 13 and each consist of two wheels or rollers 17 having a lateral spacing and a wheel axle 28 connecting them which is journalled in the lower region of the two flanks of the track carriers 14, i.e. of the wheel supporting beams. The wheel axle 28 is either rotatably journalled in the flanks or the wheels are rotatably journalled on the fixed axle 28. It is important that the wheels 17 are located close to the associated flanks of the track carrier 14, whereby the wheel axle 28 can be made relatively weak without this leading to bending of the same.
The arrangement of the wheels 17 and of the wheel axle 28 is such that the vehicle pallet 13 is displaceable on a parking floor 30 or on a lift platform 12, for example as can be seen from FIG. 7, in the longitudinal direction of the track carriers 14.
In accordance with FIG. 4 the cross-beams 18, 20 are preferably made wedge-shaped such that they can serve as an abutment surface for the front vehicle wheels 21, 21' or the rear vehicle wheels 24, with it being assumed that the vehicle wheels 21, 24 belong to a vehicle with the maximum wheel base, the vehicle wheels 21', 24' to a vehicle with a short wheel base.
In order that vehicles with a short wheel base in accordance with the broken-line illustration of the front wheels 21' and of the rear wheels 24' can be retained in trouble-free manner on the vehicle carrying pallet 13, a spacing is provided between the cross-beams 18 and 19 which takes account of the diameter of the front wheels 21, 21' in such a way that vehicle front wheels 21 or 21' located between the cross-beams 18, 19 are reliably held in both directions of travel.
The wheel supporting beams 14 are closed off at the ends with sheet metal heads 93 which contribute further to increasing the stability. For this purpose the sheet metal heads 93 of FIGS. 4 and 5 are also bent over at the lower end towards the vehicle carrying pallet 13 and also secured there to the wheel supporting beams 14 in order to also close the downwardly open U-section in box-like manner at both ends.
In accordance with FIG. 5 the cross-beams 18, 19, 20, can be manufactured from relatively thin bent sheet metal and are advantageously bolted to the wheel supporting beams 14 at 91.
The lower part of the wheel supporting beams 14 is effectively loaded in tensile strain which is above all picked up by the angled portions 15, while the upper support surface picks up both the compressive strains of the load and also the transverse bending strains through the concentrated loads on the part of the tires. In this way a favorable minimum specific material loading arises which is matched to the loads and permits a very small material thickness.
With the eccentric loading cases which necessarily arise, in particular due to heavy wide track vehicles, the torsion or stiffness generated by the box construction also signifies a more uniform load distribution to the individual wheels or rollers 17.
It is of particular significance for the invention that the upper support surface of the wheel supporting beams 14 is free of lateral boundaries. Since the tread of the vehicle tires only amounts to ca. 75% of the tire width the upper width of each wheel supporting beam 14 can be dimensioned to be less than half the difference between the largest outer width and the smallest inner width between the wheel pairs of the vehicle on the same axle. The length of the wheel supporting beams 14 is restricted to the longest wheel base (21-24 in FIG. 4) which arises so that the gross ground area of the vehicle carrying pallet 13 only amounts to approximately 60% of the gross area of the parking box 11 (see for example FIGS. 6, 8) in which it is to be accommodated and to only 30% net.
As a result of the construction of the invention a material saving of circa 50% is achieved in comparison to known embodiments. Even higher are the savings of manufacturing wage costs through a centralized series-wise production of the individual parts of the design. In addition, the type of connection of the cross-beams 18, 19, 20 illustrated in FIG. 5 by means of screw connections at 91 makes it possible to transport the pallets broken down into individual parts, whereby transport with installation on site can be carried out at a particularly favorable cost.
The wheel supporting beams 14 of the invention can be manufactured and produced at favorable price in series by using a largely automated CIM production with essentially two working steps which consist in an automatic stamping of all holes of the pre-cut sheet metal plates and subsequent folding.
In FIG. 6 the vehicle carrying pallet 13 of FIGS. 1 to 5 is illustrated in its parked position in a parking box 11, the boundaries of which are indicated in broken lines at 94. They are aligned approximately with the side edges of an adjoining lift platform 12 (FIG. 7).
In FIG. 7 the vehicle carrying pallet 13 is shown in broken lines in its transport position on a lift platform 12 which can be lifted and raised and can optionally also be horizontally moved in a lift shaft with front and rear lift shaft edges 25, 26.
A shifting beam 23 which extends from one lift shaft edge 25 to the other lift shaft edge 26 in the direction of the vehicle carrying pallet 13 is provided on the lift platform 12 and is axially displaceably arranged in both directions on carrying guide rollers 36 which are illustrated in detail in FIGS. 11 and 13 and are rotatably secured to the lift platform 12 about vertical axes. The shifting beam 23 extends practically from the front to the rear end of the lift platform 12 and is secured against collision at its two ends by wheels 40 with horizontal and transversely extending axes.
At the level of the front and rear regions of a vehicle carrying pallet 13 arranged in its transport position on the lift platform 12 there are provided motor transmission drive groups 32. These are pivotally arranged at the side about vertical hinges 35 on the shifting beam 23 and carry friction wheels 22 with vertical axes at their ends remote from the shifting beam 23, with the wheels 22 being drivable by the motor-transmission drive groups to execute a rotational movement in both directions. The angle α (FIG. 10) is of particular significance for a trouble-free drive, in particular for a hard acceleration of the vehicle carrying pallet 13 to be moved as will be explained further below with reference to FIGS. 10 and 12.
The shifting beam 23 can be displaced from the rest position of FIG. 7 into a parking box 11 into the position evident from FIG. 6 by later described drive means when the lift platform 12 is aligned with the floor 30 of the parking box 11. A corresponding movement is also possible in the reverse direction in the direction of the shaft edge 26, so that the drive means makes it possible to transfer the vehicle carrying pallet 13 in both directions.
A transfer process out of the position of FIG. 7 proceeds for example in such a way that first of all the shifting beam 23 is displaced in the direction of the arrow in FIG. 7 into the parking box 11 with which the lift platform 12 has previously been aligned, with the rear friction wheels 22 in FIG. 7 which, in the same way as the front friction wheels, are not initially driven, transmitting, as a result of the opening angle α of the motor transmission drive groups 32, the drive forces rearwardly onto the flanks of the wheel supporting beams 14. As soon as the shifting beam 23 has reached the position evident from FIG. 6 the front friction wheels 22 take on the further transport as a result of the rotational drive by the motor transmission drive groups 32. Despite the rearwardly opening angle of the front friction wheels 22 a slip-free drive force transmission to the vehicle carrying pallet 13 takes place because the friction wheels 22 are pressed by springs 34 evident from FIG. 10 against the flanks of the wheel supporting beams 14 with a suitable force. Acceleration of the vehicle carrying pallet 13 has already commenced through the rear friction wheel pair of the advancing shifting beam 23. The driven front friction wheels 22 thus also only need to maintain the already prevailing movement until the end position of the vehicle carrying pallet 13 within the parking box 11 evident from FIG. 6 has been reached. The drive of the motor-transmission drive group 32 is then reversed and the shifting beam 23 is simultaneously drawn back into the rest position evident from FIG. 7. The lift platform 12 can now be moved to some other parking box 11 or to a loading space 66 in accordance with FIG. 16 or to an unloading space 67 in accordance with FIG. 17 in order to pick up other pallets 13 there.
With such a transfer of the vehicle pallet 13 from the parking box 11 onto the lift platform 12 the shifting beam 23 stationed on the latter is first extended in the direction of the box 11 with the friction wheels 22 turning with the same peripheral speed in the rearward direction until the front pair of wheels has reached the flanks of the wheel supporting beams 14 and after a short travel stands in force-transmitting communication with them. The shifting beam displacement is then reversed while the friction wheels continue to turn and the vehicle pallet 13 is conveyed to the middle of the lift platform 12 with the sum of the two speeds. The increased drivability of the friction drive necessary during the acceleration is achieved by the automatically arising enhancement of the contact pressure of the friction wheels through the action of the control angle α of the drive groups 32. In the two functional procedures described above the retardation of the loaded pallet is ensured in that the travel resistance of the rolling pallet is increased by the negative acceleration generated by the friction wheels, and indeed as a compensation for the reduction of the contact pressure by the reversal of the action of the control angle α.
FIG. 10 shows an enlarged partial view of a vehicle carrying pallet 13 located in a parking box 11 with the shifting beam 23 however extending away from the lift platform 12 as in FIG. 6 but in precisely the opposite direction. In other respects, the relationship between the shifting beam 23 and the vehicle carrying pallets 13 which is located in its end position is the same as in FIG. 6.
It can be seen from FIGS. 10 and 11 that the shifting beam 23 has a downwardly open, C-shaped cross-section with sigma-like side walls into which the carrying guide rollers 36 engage from the inside. The motor-transmission drive groups 32 are pivotally mounted about the vertical hinge axes 35 on the shifting beam 23 by means of carriers 92. Cranked levers 69 loaded by springs 34 are likewise hinged to carriers 68 secured to the shifting beam and bias the friction wheels 22 secured to the ends of the motor-transmission drive groups 32 remote from the hinges 35 against the inner flanks of the wheel supporting beams 14.
An acute angle α is provided between the straight lines between the hinges 35 and the contact position 33 between the friction wheels 22 and the flanks of the wheel supporting beams 14. In this way, on driving the shifting beam 23 in the direction of arrow B the contact pressure force of the friction wheels 22 against the flanks of the wheel supporting beams 14 correspondingly enhances the acceleration of the drive, whereas when the drive is in the opposite direction the contact pressure of the friction wheels 22 on the flanks is reduced. This effect is exploited in accordance with the invention to increase the drive force transfer during the acceleration phase and to reduce it once the movement of the vehicle carrying pallet has been initiated and only needs to be maintained.
The FIGS. 8, 9 and 12, 13 show the same arrangements as the FIGS. 6, 7, 10 and 11 of another embodiment which operates with a central lower auxiliary rail 31 on the vehicle carrying pallet 13 and with a shifting beam 23' which, in accordance with FIG. 13, has a cross-section corresponding to an upwardly open C with sigma-shaped side walls. The embodiment of FIGS. 8, 9, 12, 13 operates in the same manner as that described with reference to FIGS. 6, 7, 10 and 11 apart from the fact that the shifting beam 23' is guided and held by carrier support rollers 36 which act from both sides from the outside and that the friction Wheels 22 are biased onto a central auxiliary rail 31 and act on this drive-wise.
The wheels arranged at the front and rear ends of the shifting beam 23, 23' serve as security against small differences in level between the lift platform 12 and the floor 30, 30' of the parking box 11 or loading and unloading spaces 66, 67 aligned therewith. In accordance with the invention, when the danger of level differences which are too great is present, an installation is provided with resilient bearings with overload contacts in the rolls or wheels 40, with the contacts being so connected with the control that they switch off the extension movement on responding and thus prevent damage of the different components which are movable relative to one another. In accordance with the invention, with a joint drive of the vehicle carrying pallets 13 by the friction wheels 22 and the shifting beams 23 or 23', respectively, both elements each take on half the effective speed of travel of the vehicle carrying pallet. The two drives preferably start-up sequentially, whereby in the critical first start up phase the correspondingly smaller acceleration favors the security of the vehicle on the pallet 13.
The symmetrical arrangement of the friction wheels 22 and their drives on both sides of the central longitudinal axis of the vehicle carrying pallet 13 is of particular importance.
In accordance with a particularly preferred embodiment of the invention the motor-transmission drive groups 32 are formed for lateral adjustment and fixation in the region of the hinge 35 transverse to the longitudinal direction of the shifting beam 23, 23' (see the double-arrow in FIGS. 10, 12), whereby the angle α can be set to a desired value.
If this angle α is selected in accordance with the illustrations in FIGS. 10 and 12 to be equal to approximately 30° to the longitudinal direction of the shifting beam 23, 23' then, on acceleration of the drive in the direction of the lift platform 12, a greater pressure and force-locked transmission of the friction wheels 22 to their drive surfaces is achieved automatically by the reaction force and without increasing the spring force by ca. the factor 1.7. The reduction of the contact pressure force which arises on driving in the reverse direction to ca. 0.7 times the static pressure does not have a disadvantageous effect since during braking, and with the vehicle carrying pallet 13 travelling, at most half the drive force is required. Thus, as a result of the arrangement of the invention, the static spring force can be reduced by ca. 40% in comparison to customary friction wheel drives, which both facilitates the run-in of the friction wheels onto the contact surface and also reduces the wear.
In FIGS. 14 and 15 the lift platform 12 with a vehicle carrying pallet 13 thereon which in turn carries a vehicle 70 is illustrated in a conveyor shaft with shaft edges 25, 26, with the special feature lying in the fact that the lift platform 12 has two plateaus 41, 42 intended for receiving vehicle pallets 13 of which the one 41 is exclusively associated with the pallets loaded with a vehicle, whereas the other auxiliary plateau 42 arranged closely beneath it, or above it, accommodates exclusively unloaded pallets.
Both said plateaus 41, 42 are equipped with a pallet transfer apparatus in accordance with the invention. These operate independently from one another and consist of shifting beams 23, 23' friction wheel drives 32 and associated parts, with the drive of each shifting beam taking place by a toothed belt 38 which is shown in broken lines and which is guided around deflection rollers 37 at the front and rear ends of the plateaus 41, 42 and is fixedly connected at 39 with the respective shifting beam 23, 23'. By driving one of the deflection rolls 37 the shifting beam 23, 23' can be displaced in this way in the one or other direction. The toothed belt 38 is also schematically illustrated in cross-section in FIGS. 11 and 13.
In accordance with the method of the invention the two plateaus 41, 42 are each alternatively occupied by one exchanged pallet prior to and after a pallet exchange has taken place. Accordingly the transfer drives as shown in FIGS. 6 to 9 are likewise alternatively actuated with a corresponding connection (alignment) of the respective plateau to one parking box or one loading or unloading station.
The drive speed for the transfer of unloaded pallets 13 into or out of the auxiliary pallet 42 is advantageously substantially higher, for example more than twice that of pallets loaded with vehicles into or out of the main plateau 41, whereby the transfer times are approximately halved and the total parking cycle is substantially shortened.
FIG. 16 shows the loading space 66 in which a vehicle carrying pallet 13 in accordance with the invention is arranged with support rolls 29 being located beneath the vehicle loading pallet 13 and engaging from below on the stiffening runners 15 of the wheel supporting beams 14.
The vehicle 70 illustrated in FIG. 16 has been driven onto the pallet 13 from a track 71 which is located at approximately the same level as the upper surface of the vehicle carrying pallet 13. At the front both the pallet 13 and also the vehicle 70 is secured against being advanced by a buffer apparatus 95 described in detail below. The pallet 13 is located in front of the lift door 47 which is opened as soon as the lift platform 12 is located at the correct position in the lift shaft.
The support rollers 29 are also provided at the floor of the discharge space 67, i.e. the unloaded station or space, illustrated in FIG. 17 and relieve the vehicle carrying pallet 13 when the vehicle 70 is driven out.
Guide beams 43 for the vehicle wheels which run up onto the pallet 13 are provided in FIGS. 18 and 19 to the sides at the loading space 66 and are connected via hinges 44 to outriggers 45 which in turn are locally pivotally journalled about vertical axes 46. This ensures breakdown-free and danger-free loading of pallets 13 which stand ready during parking, in particular by self-parkers, bearing in mind the narrow width of the wheel supporting beams 14 which are each restricted to the left- or right-side tire contact track of the vehicle to be parked thereon. During the loading process with the shaft door 47 closed the outriggers 45 are located in the illustrated position at an angle of approximately 20° to 30° to the direction of travel. They are however blocked by a latch 48 actuated by a door abutment 50 and a lever 49. In this way the guide beams 43 are also held at a distance alongside the track carriers 14 such that a trouble-free outer lateral guidance of the vehicle wheels on the wheel supporting beams 14 is ensured.
On opening of the shaft door 47 prior to the transfer process the compulsory position of the guide beams 43 is cancelled by actuation by means of abutments 72 which move in the direction of the arrows in that the towed lever 49 is moved along and so actuates the latch 48 that the outrigger 45 can pivot outwardly somewhat under the action of the vehicle tires which frequently stick somewhat as a consequence of the guide forces that are exerted and only minor non-deleterious, residual friction remains due to the weak return guidance springs 51 which does not prevent the transfer of the loaded pallet.
When closing the shaft door 47 after transfer of the loaded pallet has taken place and after the insertion of an exchanged empty pallet 13 the guide beams 43 are moved by weak return guide springs 51 back into the inner guidance position and are blocked by the latch 48.
In accordance with FIGS. 18 and 19 floor plates 52 are also provided in the free space between the track carriers 14 and are upwardly and downwardly pivotable in the manner which can be seen from FIG. 18 about central hinges 53. At their outer sides the floor plates 52 have downwardly pointing guide beams 54 which in the upwardly pivoted state (to the left in FIG. 18) guide the vehicle wheels 21 and 21' respectively at the inside. The floor plates 52 with the guide beams 54 thus have a double function. On the one hand they act as a closure for the inner space of the vehicle carrying pallets 13 so long as they are located for loading in the loading space 66, and, on the other hand, they also act as an inner guide for the vehicle wheels.
For the drive of the floor plates 52 there is provided an eccentric device 55 arranged in a lower floor recess which acts via push rods 57 on toggle lever mechanisms 56, 58 in such a way that on rotation of the eccentric device 55 the floor plates 52 are lifted out of the horizontal position illustrated to the right in FIG. 18 about the central hinge 53 into the position illustrated in FIG. 18 to the left of the hinge 53.
In accordance with FIG. 19 two eccentric devices 55 are provided which are spaced apart in the axial direction and which can be set in rotational movement via a connection shaft 75 from a common drive 74.
Since, in the deployed position of the floor plates 52 in accordance with the illustration to the left of the hinge 53 in FIG. 18, the toggle lever mechanism 56, 58 is extended, practically no forces caused by eventual riding up of vehicle wheels are transferred back to the drive 74.
In the lowered position of the floor plates 52 these are located beneath the level of the cross-beams 18, 19 and 20 so that the vehicle carrying pallet 13 is displaceable in unhindered manner.
Furthermore, conically divergent in-guiding rollers 59 for the inner flanks of the vehicle wheels are provided in FIG. 19 at the incoming end so that the vehicle wheels are reliably guided onto the wheel supporting beams 14.
FIGS. 20 and 21 show in detail the buffer apparatus 95 for the vehicle 70 and the vehicle carrying pallet 13 which is only schematically illustrated in FIG. 16 and which prevents an unintentional overtravel of the pallet during its loading. The upwardly pivotable buffer apparatus 95 is arranged so that it is of fixed location at the bottom of the loading space 66 and consists of two levers 76 which are upwardly pivotable about a bearing 73 at one end and which are aligned with the wheel supporting beams 14, with the free ends of the levers being provided with a roller 78 which is freely rotatable in a shell 77. The lever 76 can be upwardly pivoted against the direction of travel up to the level of or in direct contact with the front wheels 21, whereupon a centering angle 79 of approximately 60° to the circumference of the front wheel 21 arises which is substantially larger than the centering angle 80 between the front wheel and the front cross-beam 18 of the pallet 13.
The upward pivoting of the lever 76 is brought about by a counter pivoting lever 81 which carries a lifting roller 82 at its free end. The other ends of the levers 81 are rotationally fixedly connected to a drive shaft 83 which can be turned by a drive unit 84. During this the lifting roller 82 moves along the lower side of the lever 76 while lifting the latter up to and into the position illustrated in chain-dotted lines in FIG. 20. In this position the angle between the levers 76, 81 is approximately 90° so that the thrust forces which arise on driving of the vehicle wheel 21 up onto the roller 78 are not transferred to the drive 84 but rather only onto the shaft 83 and/or its bearing.
As a result of the free rotatability of the roller 78 in the shell no danger exists of the vehicle over-travelling the buffer apparatus 95 even when the front wheels 21 are driven because then the abutment rollers 78 can turn with them.
Towards the front the pivot angle of the lever 81 is restricted by an abutment 86 provided at the end of the lever 76 which moreover ensures the approximately 90° angle between the levers in the extended position. The pivoting back of the lever 81 out of the chain-dotted position in FIG. 20 also proceeds, having regard to the lifting roller 82 arranged at its end, with a low expenditure of force, even when in contact with a tire 21, with the likewise 90° angle between the lever 76, 81 having a positive effect in the deployed position.
An abutment 85 is also provided below the roller 78 on the abutment lever 76 which in the upwardly pivoted position illustrated in chain-dotted lines blocks the vehicle carrying pallet 13 in the loaded position against displacement forwardly through the braking reaction of the incoming vehicle.
The entire buffer apparatus 95 is accommodated in the retracted state in a recess 87 of the floor.
The recess 87 is bridged in the direction of travel of the vehicle carrying pallet 13 by rail pairs 88 at each side which have an upwardly open U-section and which accommodate and guide the wheels 17 of the vehicle carrying pallet 13. For the support of the rail pairs 88, beams 89 are laid in the recess which lie on a base plate or a plurality of base beams 90 provided at the base of the recess 87.
The buffer apparatus 95 is rigid in the extended state, i.e. is not a compressible buffer. This is also not necessary since, because of the relatively small diameter of the roll 78, the tires of the front wheels 21 yield on being driven against it and thus themselves act as a buffer. The climbing up of the front wheels which is feared in the known apparatus in similar manner with the nowadays almost universal front wheel drive and unintentional pressing of the accelerator instead of braking is avoided by the buffer apparatus 95 in that, in this case, the loose roller 78 simply turns in the shell 77 and thus prevents the lifting up of the front wheels.
The invention thus provides on the whole a vehicle parking apparatus which is suitable from every point of view for automatic control by means of computers, in particular for self-service operation by the parker and which can also be economically manufactured and used, since all individual components are matched to one another in an ideal manner. | A vehicle parking apparatus comprises at least one lift platform (12) which can be brought to parking boxes (11) provided in rows in different stories of a multi-story car park and on which at least one movable vehicle carrying pallet (13) can be arranged. The vehicle carrying pallet is formed by two box-like wheel supporting beams (14) which extend in the direction of travel and which have a length corresponding to the wheel base of the vehicle types to be accommodated and also a lateral spacing corresponding to the track widths of the vehicles to be accommodated. The wheel supporting beams (14) are in the form of an inverse U with outwardly directed angled portions (15) at the lower longitudinal edges and plates (16) which connect the lower longitudinal edges together as well as longitudinal roller arrangements (17) at the front and rear ends. At least one cross-beam (18, 19, 20) is provided at the front and at the rear of the wheel supporting beams. The cross-beams connect the wheel supporting beams (14) together and form abutments for the front and rear wheels (21, 21') of the vehicle. Furthermore, friction wheels (22) and a shifting beam (23) carrying them are provided on the lift platform and serve to drive the vehicle carrying pallets (13) during transfer thereof from the lift platform (12) to the parking boxes (11) and vice versa. | 4 |
CLAIM OF PRIORITY
[0001] This patent application claims priority under 35 USC 119(e) (1) from U.S. Provisional Patent Application Ser. No. 61/216,275 filed May 15, 2009, of common inventorship herewith entitled, “Dye Stick”
FIELD OF THE INVENTION
[0002] The present invention pertains to the field of fabric dyes, and more specifically to the field of fabric dye application.
BACKGROUND OF THE INVENTION
[0003] The prior art has put forth several designs and methods for the application of dye to fabric. Among these are:
[0004] U.S. Pat. No. 1,337,009 to Foley which discloses a dye stick for inclusion in a vat of dye for dying yarn, cloth or other material. The dye stick of this reference is suspended by its ends into the vat.
[0005] U.S. Pat. No. 2,835,604 to Aronberg discloses a dye stick and process of making it. The dye stick of this reference describes dye compositions and configurations for use by children similar to crayons or chalk that function in a manner akin to paints.
[0006] U.S. Pat. No. 5,879,414 to Milazzo describes hydrous hair dyeing stick compositions useful for coloring hair.
[0007] None of these references describe the present invention.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide a dye stick useful for spot dying clothing, upholstery or other fabric articles to effectively remove unwanted spots, stains or discoloration.
[0009] It is a further object of the present invention to provide a dye stick useful for spot dying fabric wherein the intensity of the color can be adjusted to match the fabric to be dyed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 shows the dye stick of the present invention with the cap on and a second illustration showing the dye stick of the present invention with the cap off.
[0011] FIG. 2 shows a shirt having a spot thereon.
[0012] FIG. 3 shows the application of the dye stick to the spot.
[0013] FIG. 4 shows the shirt having the spot effectively removed by application of the dye stick.
[0014] FIG. 5 shows a diagram indicating the function of pressing, releasing the measured amount and clicker returning to its original position.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Each of us has highly valued, favorite articles of clothing, and upholstered seats in our car and upholstered furniture in our home. All of these articles can be easily ruined by a single spot or stain. Until now, our only recourse to such a situation would be to have the article dyed or to replace it. The present invention provides a far better, more economical alternative, and could thus make the lives of millions of consumers a little better. The present invention provides an inexpensive, practical means of spot-dying stained or spotted clothing or upholstery, aqnd is hereinafter referred to as “the Dye Stick.” The Dye Stick is a marker-type spot applicator for textile dyes, the intent of which is to enable consumers to quickly and easily spot-dye affected fabric clothing and textile upholstery.
[0016] Manufactured by the Chemicals and Chemical Preparations industry, Standard Industrial Code 2899, the Dye Stick is a plastic cylindrical vial or tube, 5 to 6 inches in length and ¾-inch in diameter. The top end of the Dye Stick is sealed with a screw-on cap. The bottom end of the Dye Stick terminates in a chisel-tip felt marker tip, and this applicator tip is covered by a snap-on removable plastic cap.
[0017] The Dye Stick contains a volume of concentrated household fabric dye, and would be produced in a wide variety of colors. These colors would not, however, attempt to match the entire range of hues represented by all existing clothing and upholstery.
[0018] An alternative embodiment provides a means for matching the Dye Stick to the article being dyed. The top cap of the Dye Stick, as mentioned, would be a threaded, screw-on cap. To match the color of the Dye Stick to the article being dyed, the user removes this cap and then adds small volumes of water to the dye in the Dye Stick. The sides of the Dye Stick would be calibrated with levels, such that, having purchased the Dye Stick in a basic color, the user would then add water to the appropriate level to match the color of the article being spot-dyed. A small volume of water would render a dark hue of the dye's color; a medium volume of added water would result in a medium-dark dye; and a high level of water would result in a light hue of the color.
[0019] The dyes in the various colors of the Dye Stick line are colorfast, and will not run, bleed, or be washed away in machine washing of the garment. The Dye Stick can be intended to be a single-use, disposable product, and would lend itself to display with the various colors of the Dye Stick perhaps arranged in a rainbow or spectrum pattern of colors.
[0020] The Dye Stick, a marker-type spot applicator for fabric dyes in a wide variety of colors, presents a number of distinct and significant benefits and advantages. Foremost, the Dye Stick product line enables any consumer to match the color, and dye back to its original appearance, virtually any article of clothing, fabric, or upholstery. Spots and stains on fabrics are an inevitable fact of life, and prior to the invention of the Dye Stick, such spots and stains were either impossible to remove, or too costly to deal with. Now, with the Dye Stick any consumer can quickly select a Dye Stick in the appropriate color to match the article being dyed, prepare the Stick with the simple addition of an appropriate volume of water, and then spot-dye the article back to its original appearance: no mess, no costly dying of the entire article or garment, and no trouble matching the color.
[0021] In an alternative embodiment, the dye stick comprises a compartment at the top of the dye stick that stores a solution of lightener, that is available if needed to produce a lighter hue. In this case, the user presses the retractable clicker and a measured amount of lightener will enter the dye stick and the user shakes the dye stick to mix the dye and the lightener to match the desired color of the fabric being dyed.
[0022] FIG. 5 shows a diagram indicating the function of pressing, releasing the measured amount and clicker returning to its original position. This operation is the only intricate part of the dye stick.
[0023] The Dye Stick enables consumers to reclaim articles of clothing, automobile upholstery, and other fabric or textile articles which in the past would have been irretrievably ruined by a stain or spot. Using the Dye Stick would be far easier and will appeal to all consumers, regardless of their experience or expertise in the arts of sewing or dying, as no experience is necessary. Thus, this cleverly conceived invention will serve to greatly extend the life of clothing and other fabrics, and thereby stretch the always-precious consumer dollar.
[0024] Although this invention has been described with respect to specific embodiments, it is not intended to be limited thereto and various modifications which will become apparent to the person of ordinary skill in the art are intended to fall within the spirit and scope of the invention as described herein taken in conjunction with the accompanying drawings and the appended claims. | The present invention provides a dye stick useful for spot dying clothing, upholstery or other fabric articles to effectively remove unwanted spots, stains or discoloration. Further, the present invention provides a dye stick useful for spot dying fabric wherein the intensity of the color can be adjusted to match the fabric to be dyed. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to rocket motors. More particularly, this invention relates to a solid propellant rocket motor. Additionally, this invention relates to a solid propellant rocket motor which produces mild burning reactions rather than explosions when exposed to external fires.
2. Description of the Prior Art
Navy carrier operations especially provide the potential for aircraft fuel fires to occur in the vicinity of weapons and ordnance. Many rocket motors react after about one minute of exposure to external fires and flames. The reaction can vary from a mild burning to a violent case rupture.
Past efforts to improve the heat resisting capability of ordnance items have included placing a thermal barrier on the exterior of the rocket motor casing or warhead. By thermal insulation of the rocket motor propellant or explosive, the length of time the ordance item can be exposed to fire without reaction is increased. If the fire is not extinguished within a short period of time, the internal temperature will increase and the ordnance item may ignite and explode.
Explosion and violent rupture of a heat weakened motor can occur when the propellant grain is ignited along the central void in the grain. If combustion can be limited to the outside of the grain and properly vented, the severity of the reaction is lessened.
SUMMARY OF THE INVENTION
This invention overcomes the problems of the prior art by providing a rocket motor resistant to violent explosions. While portions of the rocket motor are structurally strengthened and thermally protected, other selected stress points in the casing are left unprotected. This permits buckling of the casing at the unprotected point and a venting of the rocket motor can occur. By proper venting, a violent rupture and explosion can be averted.
OBJECTS OF THE INVENTION
Accordingly, it is an object of this invention to provide an improved solid propellant rocket motor.
A further object of this invention is to provide a fire resistant rocket motor which may be safely used in areas prone to fires. Another object of this invention is to provide a rocket motor which will undergo a small-locus case rupture and produce a mild burning reaction to prevent a dangerous build-up of interior pressure.
These and other objects of the invention will become more readily apparent from the ensuing specification when taken with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view of the device shown in its operational environment;
FIG. 2 is a view of the rocket motor case sector under thermally induced compression showing a pattern of stress "lines"; and
FIG. 3 is a view of the rocket motor.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a rocket motor 10 is seen mounted under an aircraft aboard a ship 8. In this environment, aircraft fuel spillage can result in occasional fires as shown at 7. Rocket motor 10 can then endanger the crew and damage the ship, if it should react violently to a fire.
Referring to FIG. 2, a portion of rocket motor 10 is shown represented by a cylinder. When such a cylinder is subjected to longitudinal loading, as caused by thermal expansion, stress "lines" 11 develop in a criss-cross pattern. The intersections of these stress "lines" produce points 12 at which failure will occur, in the cylinder or rocket motor 10. By emphasizing the thermally induced stresses, a failure point is engineered into the construction of the rocket motor.
Referring to FIG. 3, a rocket motor 10 is shown as including a cylindrical casing 13 constructed from steel or another suitable metal. Along the length of casing 13 run ribs 14 which, preferably, are unitarily constructed therewith as shown in FIG. 3 and are, therefore, fixedly connected to casing 13. Optionally, one large rib can be used in place of several smaller ribs. Ribs 14 are located over a predetermined portion of the rocket motor and serve to structurally strengthen or stiffen that portion of casing 13. As seen in FIG. 3, said portion is segmental in shape and extends axially of casing 13. This stiffening will help provide the compressional stress when thermal expansion results from heating. Other stiffening patterns may also be used. Various attachments and skirts connected to the rocket motor can provide additional stiffening by keeping portions of the metal cooler.
A coating 16 covers portions of the outside of rocket motor 10. The coating may be of an insulating paint or an intumescent material and should be reflective of fuel fire radiation to protect those portions of the motor from external heat. As shown in FIG. 3 a peripheral casing area or bare patch 17 is located opposite of ribs 14 on casing 13 and is, therefore, diametrically opposite of the casing from said portion thereof over which the ribs are located. As is apparent from FIG. 3, area 17 is, in a direction axially of casing 13, disposed centrally of said portion over which ribs 14 are located. It is also apparent from FIG. 3 that ribs 14 stiffen said portion against bending in a plane passing through said portion and patch 17. Area 17 does not receive any thermal coating protection. Alternatively, this area can be coated to be thermally absorptive to radiation to enhance differential heating. Any fire will most likely occur beneath the rocket motor. Bare patch 17 should be situated on the bottom or underneath side.
When rocket motor 10 undergoes external fuel fire heating, the stiffening or strengthening provided by ribs 14 along the top of casing 13, combined with bare patch 17 along the bottom of casing 13 will generate stress at a predetermined stress point.
FIG. 3 shows that casing 13 surround a mass of propellant of grain 21. As is conventional, grain 21 has a central void 22 with a plurality of radially extended slots 23. Four slots 23 are shown in this star grain, but any number of radial or longitudinal extensions may be used in accordance with good motor design techniques. The shape of void 22 controls combustion characteristics of the rocket motor. When ignition occurs along this void in a heat weakened motor, destructive explosion or combustion is likely unless venting is sufficient.
Bare patch 17 is preferably located, circumferentially of the casing, between a pair of the radial slots 23 as is apparent from FIG. 3, so that casing 13 will rupture at a stress point 11 in a small region between the radial slots. Then, grain 21 will be externally ignited on a small area and burn in a manner to torch a large hole in casing 13, before the grain burns through a slot 23 or void 22. The resultant venting can prevent interior pressure from reaching a dangerous level and causing explosive destruction.
The foregoing description taken together with the appended claims constitute a disclosure such as to enable a person skilled in rocket motor arts and having the benefit of the teachings contained therein to make and use the invention. Further the structure herein described meets the objects of the invention and generally constitutes a meritorious advance in the art unobvious to such a person not having the benefit of these teachings.
Obviously many modifications and variations of this invention are possible, and, it is therefore understood that within the scope of the disclosed inventive concept, the invention may be practiced otherwise than specifically described. | In a rocket motor having an insulative coating on selected portions of thexterior casing, one or more ribs are used to structurally strengthen portions of the casing and to reinforce thermal stress patterns which will cause failure venting at a predetermined point of the rocket motor as a cook-off safety feature. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a head position control method and disk storage device for controlling the position of a read head or read/write head on a rotating storage disk, and more particularly, to a head position control method and a disk storage device mounted with two or more heads.
2. Description of the Related Art
A disk storage device has a disk for storing data, a motor for rotating the disk, a head for recording and regenerating information onto the disk, and an actuator for moving the head to a target position on the disk. Typical disk storage devices of this kind are a magnetic disk device (hard disk drive, or HDD), or an optical disk device (DVD-ROM or MO).
FIG. 26 is a compositional diagram of a conventional head position control system, and FIG. 27 is an illustrative view describing the eccentricity of the disk. In a magnetic disk device, a positional signal for detecting the head position is recorded onto the disk. The positional signal is constituted by a servo mark and track number, and offset information. Using the track number and offset information, the present position of the head can be ascertained.
As shown in FIG. 26 , the control system for controlling the head position according to the present position and the target position calculates the positional error (r−y) between the target position r and the present position y, in a calculator 106 , and inputs same to a controller C. The controller C is constituted by a commonly known PID controller or observer, which calculates a current for eliminating the position error and outputs the same to a plant actuator P. The actuator P is driven and the present position y is output from the head provided on the actuator P.
Moreover, in order to follow disk eccentricity, an eccentricity correction current corresponding to the selected head (disk face) is output from a table 108 storing eccentricity correction currents for each head, and is added to the command current of the controller C and supplied to the plant P.
In other words, the controller C determines the differential between the positional information and the target position, performs a calculation according to the amount of positional deviation thereof, and supplies a drive amount for driving the actuator P, for example, a current in the case of a VCM (voice coil motor), or a voltage in the case of a piezo-electric actuator, or the like.
As illustrated in FIG. 27 , in this disk device, eccentricity, in other words, misalignment between the disk center and the motor center causing the disk to rotate, causes a problem. More precisely, a problem is caused by misalignment between the rotational center when recording a servo signal onto the disk 110 , 112 , and the rotational center of the motor of the disk device. A servo signal is recorded respectively onto the disks 110 and 112 . When this signal is recorded, the eccentricity between the two disks is “0”.
However, misalignment of the two disks 110 , 112 may cause these two disks 110 , 112 to deviate from the rotational center of the motor, as illustrated in FIG. 27. A problem then arises in that the amount of such deviation will be different in the respective disks 110 , 112 . The cause of eccentricity of this kind may be from external shocks, thermal deformation, or the like. Moreover, in a system where the recording of the servo signal is performed on individual disks before assembling the device, whereupon the device is then assembled, eccentricity will invariably occur and the differential in eccentricity between disks will be large.
The differential in the eccentricity between disks means that when switching heads, the eccentricity following of the switched head is necessary. Conventionally, various types of techniques has been proposed in order to facilitate the operation of following eccentricity when switching heads.
For example, Japanese Laid-open Patent No. 2000-21104 proposes a method where, in the case of a device having eccentric misalignment between heads, an internal variable for generating an eccentricity correction current within a controller is changed when the head is switched. If an eccentricity correction control system such as that described in this example is applied, then it can be possible to suppress eccentricity, even in the case of a device having large eccentricity, and even if there is a differential in the amplitude and phase of the eccentricity between the inner and outer perimeters of the disk.
Moreover, Japanese Laid-open Patent No. 2001-283543, and others, propose a method for dealing with changes in the eccentricity and phase of the eccentricity correction current at the inner and outer perimeters occurring when the disk eccentricity is large.
Nevertheless, conventional technology, including the proposals described above, has been devised with respect to the current after head switching, or the positional error between heads. However, this technology does not take into account initial velocity or initial current immediately after head switching.
Initial velocity and initial current immediately after head switching are now described with reference to FIG. 28 and FIG. 29 .
FIG. 28 shows an example where there is a differential in the eccentricity trajectory between head 0 and head 2 , and depicts the movement of the servo signal on the face of a head 2 over a separate disk, while controlling the position of a head 0 over a certain track. In order to simplify the explanation, in FIG. 28 , the face of head 0 will be assumed to have “0” eccentricity, and only the face of head 2 will be regarded as having eccentricity. The current, velocity, and position of the face of head 2 are thus depicted.
As shown in FIG. 28 , the servo signal on the face of head 2 follows a sinusoidal trajectory having the same frequency as the rotational frequency, with respect to the servo signal on the face of head 0 . A similar explanation can be used in cases where both sides of the disk have eccentricity. In this state, head switching is performed. As shown in FIG. 29 , after switching heads, the eccentricity correction current is switched from eccentricity correction for the face of head 0 to eccentricity correction for the face of head 2 . Thereby, a step of magnitude u 0 is generated in the relative current U. Moreover, there will be an initial velocity of relative velocity V 0 corresponding to the differential between the sinusoidal trajectories of head 0 and head 2 . The relative position will also change by X 0 .
In the prior art, when switching heads, control of switching is performed by addressing only the relative position X 0 or the eccentricity correction current themselves, as illustrated in FIG. 29 . However, the current u 0 and initial velocity V 0 are not taken into account.
In the present invention, on the other hand, initially the existence of the initial velocity V 0 is investigated. When switching heads, seek control is performed. However, in a conventional control system, it is assumed that the initial velocity at head switching is 0, or that it is the same as the velocity of the previous head. “Seek control” involves performing control in such a manner that the distance to the target position becomes “0” and the speed upon reaching the target position is also “0”. However, since the initial speed is not “0”, then a corresponding disparity occurs. This disparity creates a fluctuation upon arriving at the target position, and since this fluctuation takes time to be absorbed, it causes a lengthening of the seek time.
Next, there is the problem of the step u 0 in the eccentricity correction current. If the differential in the eccentricity trajectory is large, then this step u 0 will also be large. When switching heads, this sudden change in the current stimulates the resonance of the actuator, and is a cause of fluctuation. As a means of suppressing this resonance, a current is output to the actuator via a filter, such as a notch filter, or the like. However, even if several notch filters are used, the resonance frequency component cannot be reduced fully to zero, and the notch filter waveform cannot provide 100% correction of the actuator resonance characteristics. Consequently, if there is a sudden step in the initial current u 0 as illustrated in FIG. 29 , fluctuation may occur, which in turn becomes a cause of delay in the seek time.
Therefore, it is an object of the present invention to provide a head position control method and disk device for reducing lengthening of the seek time due to the initial velocity V 0 upon switching heads.
It is a further object of the present invention to provide a head position control method and disk device for reducing lengthening of the seek time due to the initial current u 0 upon switching heads.
Moreover, it is yet a further object of the present invention to provide a head position control method and disk device for recording or reproducing data by moving an actuator to a target position at higher speed, after switching heads.
SUMMARY OF THE INVENTION
In order to achieve the aforementioned objects, one aspect of the head position control method according to the present invention is a head position control method for driving a plurality of heads by a single actuator in order to at least read different disk faces, having the steps of: calculating a servo control amount in accordance with a positional error between a target position of the head and a present position of the head; controlling the actuator by adding an eccentricity correction current corresponding to a selected head of the plurality of heads to the servo control amount; calculating differential velocity between eccentric trajectories of the respective heads when switching from one of the plurality of heads to another of the plurality of heads; and setting the differential velocity as an initial velocity in the step of calculating the servo control amount.
Preferably, in the present invention, the step of calculating the differential velocity also has a step for calculating the differential velocity on the basis of a difference between the eccentricity correction current for the one head and the eccentricity correction current for the other head.
In this embodiment of the present invention, the initial velocity when switching heads is preferably predicted and supplied to a controller, thereby improving disparity in the response, and hence making it possible to shorten the seek time.
A further aspect of a head position control method according to the present invention is a head position control method for driving a plurality of heads by a single actuator in order to at least read different disk faces, having the steps of: calculating a servo control amount in accordance with the positional error between a target position of the head and a present position of the head; controlling the actuator by adding an eccentricity correction current corresponding to a selected head of the plurality of heads to the servo control amount; calculating a differential velocity between eccentric trajectories of the respective heads when switching from one of the heads to another of the heads; and performing feed forward control for reducing the differential velocity.
More preferably, the feed forward control step also has the steps of: generating a position trajectory and current trajectory for reducing the differential velocity in accordance with the differential velocity; correcting the present position by the position trajectory; and adding the current trajectory to the eccentricity correction current and supplying same to the actuator.
In this embodiment of the present invention, the initial velocity when switching heads is preferably predicted and the correction trajectory for correcting the initial velocity when switching is supplied to a system, thereby making it possible to shorten the seek time.
A further embodiment of a head position control method according to the present invention is a head position control method for driving a plurality of heads by a single actuator in order to at least read different disk faces, having the steps of: calculating a servo control amount in accordance with the positional error between a target position of the head and a present position of the head; controlling the actuator by adding an eccentricity correction current corresponding to a selected head of the plurality of heads to the servo control amount; calculating a differential between the eccentricity correction current for the head before switching and the eccentricity correction current for the head after switching when switching from one of the heads to another of the heads; and performing feed forward control for reducing the differential.
More preferably, the feed forward control step also includes the steps of: generating a position trajectory and current trajectory for reducing the current differential in accordance with the current differential; correcting the present position by means of the position trajectory; and adding the current trajectory to the eccentricity correction current and supplying same to the actuator.
According to this embodiment of the present invention, the switching step in the eccentricity correction current when switching heads is preferably predicted and supplied to a controller, thereby eliminating residual oscillations accompanying the step, and hence making it possible to shorten the seek time.
Another aspect of the present invention is a head position control method for driving a plurality of heads by a single actuator in order to at least read different disk faces, having the steps of: calculating a servo control amount in accordance with a positional error between a target position of the head and a present position of the head; controlling the actuator by adding an eccentricity correction current corresponding to a selected head of the plurality of heads to the servo control amount; calculating a differential between the eccentricity correction currents of the respective heads before and after switching, and a velocity differential between the heads when switching from one of the heads to another of the heads; and performing feed forward control for reducing the current differential and the velocity differential.
Furthermore, it is preferable that the feed forward control step also includes the steps of: generating a first position trajectory and a first current trajectory for reducing the velocity differential in accordance with the velocity differential; generating a second position trajectory and a second current trajectory for reducing the current differential in accordance with the current differential; correcting the present position by means of the first and second position trajectories; and adding the first and second current trajectories to the eccentricity correction current and supplying same to the actuator.
According to this embodiment of the present invention, the initial velocity when switching heads is preferably predicted and a trajectory for correcting the initial velocity when switching is supplied, thereby making it possible to shorten the seek time. Moreover, when switching heads, the switching differential in the eccentricity correction current is eliminated, and therefore residual oscillations accompanying the differential can be eliminated and the seek time can be shortened.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a compositional diagram of a disk storage device according to one embodiment of the present invention;
FIG. 2 is an illustrative diagram of a disk position signal in FIG. 1 ;
FIG. 3 is a detailed illustrative diagram of the position signal in FIG. 2 ;
FIG. 4 is an illustrative diagram of a seek operation of the head in FIG. 1 ;
FIG. 5 is a functional block diagram of a first embodiment of a head position controller in FIG. 1 ;
FIG. 6 is a functional block diagram of a modification of a first embodiment of the head position controller in FIG. 1 ;
FIG. 7 is a functional block diagram of a second embodiment of the head position controller in FIG. 1 ;
FIG. 8 is a functional block diagram of a first embodiment of a correction trajectory generating section in FIG. 7 ;
FIG. 9 is a functional block diagram of a second embodiment of the correction trajectory generating section in FIG. 7 ;
FIG. 10 is a functional block diagram of a third embodiment of the correction trajectory generating section in FIG. 7 ;
FIG. 11 is a design process flow diagram of an initial velocity correction trajectory according to a first embodiment of the present invention;
FIG. 12 is an illustrative diagram of the respective design trajectories in FIG. 11 ;
FIG. 13 is a block diagram of the trajectory design in FIG. 11 ;
FIG. 14 is an illustrative diagram of a design example of an FIR filter in FIG. 11 ;
FIG. 15 is an illustrative diagram of an example of the output of a FIR filter in FIG. 14 ;
FIG. 16 is an illustrative diagram of the trajectory 1 in FIG. 11 ;
FIG. 17 is an illustrative diagram of the trajectory 2 in FIG. 11 ;
FIG. 18 is an illustrative diagram of the trajectory 3 in FIG. 11 ;
FIG. 19 is an illustrative diagram of the trajectory 4 in FIG. 11 ;
FIG. 20 is an illustrative diagram of correction of the differential in eccentricity correction current according to a second embodiment of the present invention;
FIG. 21 is an illustrative diagram of differential correction in a case where two disks have eccentricity as in FIG. 20 ;
FIG. 22 is an illustrative diagram of the operation of an actuator according to the differential correction shown in FIG. 20 ;
FIG. 23 is a design process flow diagram of a current for eliminating current differential according to a second embodiment of the present invention;
FIG. 24 is a further waveform of the differential correction current shown in FIG. 20 ;
FIG. 25 is yet another waveform of the differential correction current in FIG. 20 ;
FIG. 26 is an illustrative diagram of a control system of a conventional magnetic disk device;
FIG. 27 is an illustrative diagram of eccentric misalignment between magnetic disks;
FIG. 28 is an illustrative diagram of eccentricity correction current and the operation of an actuator; and
FIG. 29 is an illustrative diagram of switching of eccentric trajectories.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention are described herein with respect to a disk storage device, a control system according to a first embodiment, a control system according to a second embodiment, an initial velocity correction trajectory, an initial current correction trajectory, and still further embodiments. One skilled in the art will be aware, however, that the present invention is not limited to these embodiments.
FIG. 1 shows a magnetic disk device as a disk storage device. A magnetic disk 10 forming a magnetic storage medium is provided on a rotating shaft 19 of a spindle motor 18 . The spindle motor 18 causes the magnetic disk 10 to rotate. An actuator (VCM) 14 has magnetic heads 12 provided on the front end thereof, and moves the magnetic heads 12 in a radial direction of the magnetic disk 10 .
The actuator 14 is constituted by a voice coil motor (VCM) which rotates about a rotating shaft 19 . In this case, two magnetic disks 10 are installed in the magnetic disk device, and four magnetic heads 12 are driven simultaneously by the same actuator 14 .
Each magnetic head 12 is constituted by a read element and a write element. The magnetic head 12 is preferably formed by layering the read element including a magnetic resistance element onto a slider, and then layering a write element including a write coil thereupon.
A position detecting circuit 20 converts a positional signal (analog signal) read by the magnetic head 12 into a digital signal. A read/write (R/W) circuit 22 controls reading and writing, from and to the magnetic head 12 . A spindle motor (SPM) drive circuit 24 drives the spindle motor 18 . A voice coil motor (VCM) drive circuit 26 supplies a drive current to the voice coil motor (VCM) 14 , thus driving the VCM 14 .
A micro-controller (MCU) 28 detects a present position from the digital positional signal supplied by the position detecting circuit 20 , and calculates a VCM drive command value in accordance with an error between a detected present position and a target position. In other words, the MCU 28 performs position demodulation and servo control. A read-only memory (ROM) 30 stores a control program, or the like, for the MCU 28 . A hard disk controller (HDC) 32 determines the position within the disk 10 circumference by referring to a sector number of a servo signal, and implements data recording or reproduction. A random access memory (RAM) 34 temporarily stores read data and write data. The HDC 32 communicates with a host via an interface IF, such as an ATA or SCSI interface, or the like. A bus 36 connects the elements.
As shown in FIG. 2 , in each track of the magnetic disk 10 , from the outer perimeter to the inner perimeter, a servo signal (positional signal) is placed in each track, in equidistant fashion in the circumferential direction. Moreover, each track is constituted by a plurality of sectors, and the solid lines in FIG. 2 indicate the recording positions of the servo signal. As shown in FIG. 3 , the positional signal is constituted by a Servo Mark, track number (Gray Code), Index, and offset information (PosA, PosB, PosC, PosD).
Using the track number (Gray Code) and the offset information (PosA, PosB, PosC, PosD), it is possible to detect the position of the magnetic head in the radial direction. Moreover, it is also possible to ascertain the position of the magnetic head in the circumferential direction on the basis of the index signal Index. For example, a sector number is set to 0 when the index signal is detected, and each time a servo signal is detected, the sector number is incremented, thereby providing a sector number for each sector in a track.
The sector number in the servo signal is used as a reference when performing data recording or data reproduction. The index signal is generated once per disk revolution, or alternatively, instead of an index signal, it is also possible to provide a sector number.
FIG. 4 is a seek control example for an actuator as implemented by the MCU 28 in FIG. 1 . The MCU 28 confirms the position of the actuator via the position detecting circuit 20 in FIG. 1 , performs a servo calculation, and supplies an appropriate current to the VCM 14 . FIG. 4 illustrates the transition in the control performed after the start of seeking to move the head 12 from a certain track position to a target track position, together with the current of the actuator 14 , the actuator (head) velocity, and the actuator (head) position.
In other words, the seek control operation is able to move the head to a target position by transferring between coarse control, settling control, and following control. Coarse control essentially involves velocity control, and settling control and following control essentially involve positional control. In either case, it is necessary to detect the present position of the head.
In order to confirm a position in this manner, as shown in FIG. 2 (described previously), a servo signal is previously recorded onto the magnetic disk 10 . In other words, as illustrated in FIG. 3 , a signal comprising a servo mark indicating the start position of a servo signal, a gray code indicating a track number, an index signal, and PosA-D indicating an offset, are recorded onto the disk 10 . This signal is read out by the magnetic head 12 , and the servo signal is converted to a digital value by the position detecting circuit 20 . The MCU 28 modulates the head position and controls the actuator 14 by means of the control system described with reference to FIG. 5 below.
The embodiments shown in FIG. 5 and FIG. 6 determine the initial velocity when switching heads and initialize the controller C with the determined initial velocity. According to this embodiment, the deviation in the controller C caused by the initial velocity can be eliminated.
As shown in FIG. 5 , a control system for controlling the position of the head from the present position to a target position is constructed of a computing unit 10 , which calculates the positional error (r−y) between the target position r and the present position y, and inputs same to the controller C. The controller C is constituted by a commonly known PID controller or observer, and calculates a current for eliminating the positional error, which it then outputs to the actuator P forming the plant. The actuator P is driven and the present position y is output from the head 12 provided on the actuator P.
Moreover, in order to follow the eccentricity of the disk 10 , an eccentricity correction current corresponding to the selected head (disk face), Head, is output from a table 44 storing the eccentricity correction current for each head, added to a command current for the controller C by computing unit 42 , and supplied to the plant P.
In other words, the controller C determines the differential between the positional information and the target position, performs a calculation according to the magnitude of this positional deviation, and supplies a drive quantity for driving the actuator P, for example, which is a current in the case of a VCM (voice coil motor), or a voltage in the case of a piezo-electric actuator, or the like.
When switching heads, an initial velocity from an initial velocity predicting section is set in the controller C. This initial velocity predicting section determines an initial velocity V 0 from the eccentricity correction current. The initial velocity predicting section has an eccentricity correction current table 46 , a current differential calculating section 48 for calculating the differential between the eccentricity correction currents of the two heads before and after switching, and a velocity calculating section 50 for calculating an initial velocity when switching heads from the differential in the eccentricity correction current.
Since the eccentricity can be represented by a sinusoidal wave, the eccentricity correction currents are also respective sinusoidal waves. These sinusoidal waves consist of a cosine component and sine component. The eccentricity correction current table 46 stores a cosine component and sine component of the eccentricity correction current for each position (zone) of the disk, and for each head.
When switching heads, the current differential calculating section 48 determines the cosine component and sine component of the head number HeadOld before switching and the head number Head after switching, in the zone of the current track Track from the eccentricity correction current table 46 , and it derives the differentials Ucos, Usin between the cosine components and sine components of the two heads, and hence determines the differential in the eccentricity trajectories, in current units.
If the current is integrated, then the integral value is directly proportional to the velocity, and hence the velocity calculating section 50 integrates the current from the current differential calculating section 48 , calculates the initial velocity V 0 of the switching sector position Sector and sets the same in a controller C.
When switching heads, the controller C is set to this initial velocity V 0 , and it performs the seek control illustrated in FIG. 4 in accordance with the set initial velocity V 0 , and in accordance with the differential between the target position and the present position. In FIG. 5 , the eccentricity correction current tables 44 and 46 are shown to be used in conjunction.
Next, the control system in FIG. 6 is explained. Elements which are the same as those in FIG. 5 are similarly labelled in FIG. 6 . The composition of FIG. 6 is the same as that in FIG. 5 , with the exception that the initial velocity predicting section is composed differently.
The composition shown in FIG. 6 is particularly effective in cases where a servo signal is recorded onto disks externally, and the disks are then assembled into the storage device. First, the positional deviation in the radial direction of two heads is measured in the circumferential direction. The change in the positional deviation in the radial direction is a sinusoidal wave. Therefore, the positional deviation in the radial direction is measured in sequence in sector 0 and sector 1 , and this deviation waveform is subjected to a Fourier transform to determine sine and cosine coefficients, which are stored in a eccentric positional deviation table 52 . A table 52 of this kind is provided for each head. Moreover, measurements are preferably made for a plurality of locations (zones), and not just once for each head.
When switching heads, a positional differential calculating section 54 determines the cosine component and sine component of the head number HeadOld before switching and the head number Head after switching, in the zone of the current track Track from the eccentric positional deviation table 52 . Differentials Pcos, Psin are thus derived between the cosine components and sine components of the two heads, and the differential in the eccentricity trajectories are determined in positional units.
If these positions are differentiated, the differential value will be directly proportional to the velocity, and hence the velocity calculating section 56 differentiates the positional differential from the positional differential calculating section 54 , calculates the initial velocity V 0 of the switching sector position Sector, and sets V 0 in the controller C.
When switching heads, the controller C is set with this initial velocity V 0 and thereafter performs seek control as shown in FIG. 4 , in accordance with the initial velocity V 0 thus set, and in accordance with the differential between the target position and the present position.
In this way, an initial velocity is determined from the positional deviation and eccentricity correction current, and when switching heads, this initial velocity is set and seeking is started after the head has been switched. Therefore, it is possible to shorten the seek time due to the initial velocity of the head when switching heads.
In the embodiment shown in FIG. 7 , the initial velocity and current step when switching heads are determined, a correction position trajectory and a correction current are generated, and the present position and the eccentricity correction current are corrected. According to this embodiment, the state signals are corrected without changing the controller C, and hence deviation upon switching can be eliminated.
In FIG. 7 , elements which are the same as those illustrated in FIG. 5 and FIG. 6 are similarly labelled. A correction trajectory generating section 60 generates a position correction trajectory and a current correction trajectory from the head before switching HeadOld, and the head after switching Head. An adder unit 62 adds the current correction trajectory to the eccentricity correction current determined for the head after switching Head from the eccentricity correction table 44 , thereby eliminating a step when switching heads. A computing unit 64 subtracts the position correction trajectory from the present position y and outputs the same to the computing unit 40 .
In other words, the correction trajectory generating section 60 supplies a trajectory for reducing the initial velocity to zero, externally, to the controller C. The controller C is a conventional type of controller with an initial velocity setting of “0”. By adopting this composition, it is possible to adapt to the initial velocity, while maintaining the same structure as a conventional controller C. Moreover, the correction trajectory generating section 60 calculates a trajectory including the current for eliminating the current step corresponding to the initial current u 0 and corrects the eccentricity correction current accordingly. Therefore, it is also possible to adapt to the initial current, while maintaining the same structure as a conventional controller C.
Next, a first embodiment of the correction trajectory generating section 60 shown in FIG. 7 is described, with reference to FIG. 8 . This correction trajectory generating section 60 determines the initial velocity V 0 and current step U 1 from the eccentricity correction current. Thereupon, the section 60 generates a position correction trajectory and current correction trajectory by multiplying by a normalized correction trajectory which reduces this initial velocity and current differential to zero.
The section generating the difference between the eccentricity correction currents of the two heads is constituted by the eccentricity correction current table 46 and the current differential calculating section 48 which calculates the differential between the eccentricity correction currents of the two heads, before and after switching, similarly to FIG. 5 and FIG. 6 .
As stated previously, eccentricity can be represented by a sinusoidal wave, and the eccentricity correction currents can also be taken as respective sinusoidal waves. This sinusoidal wave consists of a cos component and sin component. The eccentricity correction current table 46 stores a cosine component and sine component of the eccentricity correction current for each location (zone) of the disk, for each head.
When switching heads, the current differential calculating section 48 determines the cosine component and sine component of the head number HeadOld before switching and the head number Head after switching, in the zone of the current track Track from the eccentricity correction current table 46 , and it derives the differentials Ucos, Usin between the cosine components and sine components of the two heads, and hence determines the differential in the eccentricity trajectories, in current units.
An initial velocity and current step calculating section 58 outputs the cosine component and sine component of the differential in the eccentricity correction currents, and therefore the initial velocity and initial current are determined using these two values and the current sector number. In other words, if the current is integrated, then the integral value is directly proportional to the velocity, and hence the calculating section 58 integrates the current from the eccentricity correction current differential calculating section 48 , and calculates the initial velocity V 0 of the switching sector position Sector. Moreover, the step U 1 in the eccentricity correction current is calculated according to the differential between the cosine component and sine component of the respective head at the time of head switching.
Thereupon, two trajectories, one (current, position) for correcting the initial velocity, and another (current, position) for correcting the initial current, are determined by the method described below, and are stored respectively in a velocity correction trajectory table 70 and current differential correction table 76 . The position correction trajectory and the current correction trajectory in the respective tables 70 , 76 are multiplied by the initial velocity V 0 and initial current U 1 , and are respectively added by adder units 72 , 78 . The position trajectory and current trajectory corrected respectively to the magnitude of the initial velocity and initial current from the multipliers 72 , 78 are added by respective adder units 74 , 80 , to obtain a trajectory which corresponds to both the initial velocity and the initial current.
FIG. 9 illustrates a second embodiment of a correction trajectory generating section 60 in FIG. 7 . This correction trajectory generating section 60 determines the initial velocity V 0 from the eccentricity correction current and multiplies this initial velocity by a correction trajectory which reduces the velocity to zero, thereby generating a position correction trajectory and a current correction trajectory corresponding to the magnitude of the initial velocity.
The section generating the difference between the eccentricity correction currents of the two heads is constituted by the eccentricity correction current table 46 and the current differential calculating section 48 which calculates the differential between the eccentricity correction currents of the two heads, before and after switching, similarly to FIG. 5 and FIG. 6 .
As stated previously, eccentricity can be represented by a sinusoidal wave, and the eccentricity correction currents can also be taken as respective sinusoidal waves. This sinusoidal wave consists of a cosine component and sine component. The eccentricity correction current table 46 stores a cosine component and sine component of the eccentricity correction current for each location (zone) of the disk, for each head.
When switching heads, the current differential calculating section 48 determines the cosine component and sine component of the head number HeadOld, before switching and the head number Head after switching, in the zone of the current track Track from the eccentricity correction current table 46 , and it derives the differentials Ucos, Usin between the cosine components and sine components of the two heads, and hence determines the differential in the eccentricity trajectories, in current units.
Since the cosine component and sine component of the differential of the eccentricity correction currents is output by the initial velocity calculating section 50 , the initial velocity is determined using these two values and the current sector number. In other words, when the current is integrated, it is directly proportional to the velocity, and hence the calculating section 50 integrates the current from the eccentricity correction current differential calculating section 48 to calculate the initial velocity V 0 for the switching sector position Sector.
Thereupon, a trajectory for correcting the initial velocity is determined, by the method described below, and stored in a velocity correction trajectory table 70 . A multiplier 72 then multiplies the initial velocity V0 respectively by the corrected position trajectory and corrected current trajectory in table 70 . A trajectory corresponding to the initial velocity is obtained from the position trajectory and current trajectory corrected to the magnitude of the initial velocity output by the multiplier 72 .
In other words, in the present embodiment, a trajectory for reducing the initial velocity to zero is supplied externally to the controller, and the table 76 , adders 74 , 80 , and multiplier 78 in FIG. 8 are eliminated. Therefore, it is possible to use a conventional type of controller C with an initial velocity set to 0, and hence it is also possible to adapt to the initial velocity, while maintaining a conventional controller structure.
Next, a third embodiment of the correction trajectory generating section 60 shown in FIG. 7 is described with reference to FIG. 10 . This correction trajectory generating section 60 determines the current differential U 1 from the eccentricity correction current. Thereupon, it multiplies the current differential U 1 by a correction trajectory which reduces the initial differential to zero, and hence generates a position correction trajectory and a current correction trajectory.
The section generating the difference between the eccentricity correction currents of the two heads is constituted by the eccentricity correction current table 46 and the current differential calculating section 48 which calculates the differential between the eccentricity correction currents of the two heads, before and after switching, similarly to FIG. 5 and FIG. 6 .
As stated previously, eccentricity can be represented by a sinusoidal wave, and the eccentricity correction currents can also be taken as respective sinusoidal waves. This sinusoidal wave consists of a cosine component and sine component. The eccentricity correction current table 46 stores a cosine component and sine component of the eccentricity correction current for each location (zone) of the disk, and for each head.
When switching heads, the current differential calculating section 48 determines the cosine component and sine component of the head number HeadOld before switching and the head number Head after switching, in the zone of the current track Track from the eccentricity correction current table 46 , and it derives the differentials Ucos, Usin between the cosine components and sine components of the two heads, and hence determines the differential in the eccentricity trajectories, in current units.
Since the cosine component and sine component of the differential of the eccentricity correction currents is output, the initial velocity calculating section 50 - 2 , calculates the initial current by using these two values and the current sector number. In other words, the differential U 1 in the eccentricity correction currents is calculated from the differential between the cosine components and sine components of the respective heads involved in head switching, in the switching sector position Sector.
Thereupon, a trajectory for correcting the initial current is determined, by the method described below, and stored in a current correction trajectory table 76 . A multiplier 78 then multiplies the initial current U 1 by the corrected position trajectory and corrected current trajectory in the table 76 . A position trajectory and current trajectory corrected to the magnitude of the initial current are output by the-multiplier 78 .
In other words, in the present embodiment, a trajectory for reducing the initial current to zero is supplied externally to the controller, and the table 70 , and adders 72 , 74 , 80 in FIG. 8 are eliminated from the composition. Therefore, it is possible to adapt to the initial current, whilst maintaining a conventional controller structure.
Next, a trajectory for correcting the initial velocity stored in the initial velocity correction table 70 will be described. For this trajectory definition method, the method described in detail in Japanese Laid-open Patent No. 2000-321037 (Head position control method and device for disk device) can be used. This method is described in simple terms below.
Processing, such as is shown for the following figures, can be executed in a computer using, for example, software such as MATLAB (trade name), or the like. Trajectory definition processing is described below step-by-step in accordance with FIG. 11 .
(S 10 ) A frequency to be suppressed in the current waveform is determined. For example, the resonance frequency of the actuator 14 is selected.
(S 12 ) Thereupon, a FIR (Finite Impulse Response) filter for suppressing this frequency is configured. FIG. 14 is a frequency characteristics graph of the designed FIR filter, and illustrates an FIR filter design example for controlling an actuator having a resonance frequency of 7.6 kHz. Consequently, the FIR filter is preferably configured so as to suppress the frequency components in the region of 7.6 kHz.
(S 14 ) Next, a trajectory design model is created. As shown in FIG. 13 , a model of a FIR filter 90 , current amplifier 92 and plant (actuator) 94 is created. In this model, the output of the current amplifier 92 is a current, and the output of the plant 94 is a position. When the state of the actuator is represented by (position, velocity), then a trajectory 1 for achieving (1,0)→(0,0) is designed.
FIG. 15 is an output waveform in a case where a square waveform is supplied to the FIR filter 90 . FIG. 16 illustrates a case where a current of a magnitude sufficient to move by exactly one track has been derived with respect to the waveform in FIG. 15 . When the state of the actuator is represented by (position, velocity), then the trajectory (0,0)→(1,0). In other words, the current, velocity and position are indicated. This trajectory is equivalent to the trajectory (−1,0)→(0,0), and hence a trajectory 1 is obtained.
(S 16 ) Thereupon, a trajectory 2 for (0,0)→(X,1) is designed. FIG. 17 shows a trajectory for (0,0)→(X,1). A square wave current is obtained via the preceding FIR filter 90 , in such a manner that the velocity becomes exactly one track/sample.
(S 18 ) Thereupon, a trajectory 3 for (0,1)→(X,0) is designed. By passing the current in FIG. 17 in an opposite direction, the trajectory (0,1)→(X,0) as illustrated in FIG. 18 is obtained. Since it is not possible to determine trajectory 3 directly, trajectory 2 is determined and trajectory 3 is derived by passing the current in the opposite direction. As shown in FIG. 18 , at this stage, the position has still not reached “0”.
(S 20 ) Thereupon, a trajectory 4 for (0,1)→(0,0) is designed. In other words, in order to return the position of trajectory 3 in FIG. 18 to “0”, the sum of trajectory 3 in FIG. 18 , and trajectory 1 in FIG. 16 , which cancels out the remaining position of the trajectory 3 in FIG. 18 is performed, thereby yielding the trajectory (0,1)→(0,0) in FIG. 19 . The trajectory in FIG. 19 is thus the trajectory for correcting the initial velocity. In other words, it is a normalized current and position trajectory for reducing the velocity “1” to velocity “0” as shown in FIG. 19 .
(S 22 ) The normalized current trajectory and position trajectory in trajectory 4 is stored in table 70 as a velocity correction trajectory.
FIG. 12 illustrates the relationships between the aforementioned trajectories 1 - 4 . The correction trajectory for reducing the initial velocity to “0” is trajectory 4 . Since this trajectory is not determined directly, trajectory 1 for moving the position only, and trajectories 2 and 3 for changing the position and velocity, are configured and the trajectory 4 for returning the position of trajectory 3 to “0” is then also configured. According to this embodiment, it is possible to correct the initial velocity to “0”.
A method of defining a trajectory for correcting the step differential in the eccentricity correction current when switching heads is now described. FIG. 20 is an illustrative diagram of the correction of eccentricity correction current step differentials. The problem presented by the initial current u 0 in FIG. 29 is the value of u 0 itself. As shown in FIG. 20 , by applying a current in the opposite direction to the original current waveform having the initial current u 0 , in such a manner that the value of u 0 becomes “0”, it is possible to prevent the occurrence of a current differential when switching heads, as illustrated by the synthesized current waveform in FIG. 20 .
In other words, a step differential eliminating current should be applied which has a waveform with an initial value of −u 0 , reducing to 0 after a prescribed time period has elapsed. In the middle diagram in FIG. 20 , a triangular wave is used as an example of this waveform. Consequently, it is possible to eliminate the current step differential, in the manner illustrated by the bottom diagram in FIG. 20 .
FIG. 21 shows the state of an eccentricity correction current when both disks are taken as being eccentric. In a case where both faces are eccentric, then if the heads are simply switched, a step differential will be generated in the current, as illustrated by the middle diagram. However, it is possible to eliminate this step differential by applying a correction current when switching heads.
Using this correction current alone, a problem occurs in that the fact of applying a surplus step differential eliminating current as illustrated by the middle diagram in FIG. 20 causes a corresponding movement in the actuator. FIG. 22 is an illustrative diagram of the actuator operation caused by this step differential eliminating current. FIG. 22 shows the change in position and velocity when the triangular current (differential eliminating current) shown in the middle diagram in FIG. 20 is applied to the actuator. When the triangular current has reached exactly “0”, a deviation of V 1 in the velocity and X 1 in the position occurs.
In order to eliminate this deviation in the velocity and position, a trajectory design is adopted which corrects the initial velocity as illustrated in FIG. 11 and subsequent diagrams. In other words, a correction trajectory is generated using technology which designs a trajectory reducing any position or velocity to “0”. More precisely, a trajectory (X 1 ,V 1 )→(0,0) is designed and used for correction.
FIG. 23 is a design process flow diagram of a step differential eliminating correction current of an eccentric correction current and is described below step-by-step.
(S 20 ) The waveform of a correction current for eliminating the eccentricity correction current step differential is determined. In FIG. 20 , this waveform is shown to be triangular, for example.
(S 22 ) Thereupon, a time period T 1 (see FIG. 22 ) for correcting the eccentricity step differential is determined.
(S 24 ) Next, the movement of the actuator in response to the correction current for eliminating the step differential is calculated by simulation. In other words, values are determined for the position and velocity (−X 1 ,−V 1 ) after the time period T 1 has elapsed from the start of the supply of the correction current.
(S 26 ) A trajectory for shifting the state (−X 1 ,−V 1 ) to (0,0) is configured. For this purpose, the initial position and the initial velocity are considered separately, and two trajectories are designed for (−X 1 ,0)→(0,0) and (0,−V 1 )→(0,0). The design method is similar to that described in FIG. 11 and subsequent diagrams. By synthesizing these two trajectories, the trajectory (−X 1 ,−V 1 )→(0,0) is determined.
(S 28 ) By deriving the sum of the trajectory (current trajectory for eliminating step differential) (0,0)→(−X 1 ,−V 1 ) by applying a triangular current, and the trajectory determined for (−X 1 ,−V 1 )→(0,0), it is possible to obtain a trajectory for achieving (0,0) after a specified period of time has elapsed by applying a triangular current.
(S 30 ) The trajectory (current and position trajectory) thus determined is stored in table 76 .
According to this embodiment, it is possible to eliminate the current step differential without altering the position or velocity of the actuator.
FIG. 24 and FIG. 25 show the shape of a further current for correcting step differentials in the eccentricity correction currents. Rather than triangular, the shape of this correction current may instead be a power function, such as a secondary function or tertiary function as illustrated in FIG. 24 , or a sinusoidal wave as illustrated in FIG. 25 .
As described above, the disk storage device is a magnetic disk device, but the present invention is also applicable to other types of disk storage devices, such as an optical disk device, magneto-optical disk device, or the like. Moreover, the correction method for switching heads may also be used for switching between heads on the front and rear faces of the same disk, and is not limited to a device containing two or more disks. Moreover, the shape of the disk is not limited to being circular, but may also have a card shape, for example.
The present invention has been described with reference to specific embodiments, but one skilled in the art will understand that various modifications are possible within the scope of the present invention, and that these modifications are not excluded from the technical scope of the present invention.
As described above, according to the present invention, when there is a differential between the eccentric trajectories of two heads, then the following beneficial effects can be obtained.
(1) Since the initial velocity at head switching is supplied to the controller and the disparity in the response is improved, it is possible to shorten the seek time.
(2) Since a trajectory for correcting the initial velocity at switching is supplied, it is possible to shorten the seek time.
(3) Since switching step differential in the eccentricity correction current is eliminated when switching heads, it is possible to eliminate residual oscillation accompanying the step differential, and hence the seek time can be further shortened. | A disk device has eccentric misalignment between a plurality of disk surfaces. In order to prevent transient phenomena due to differences in the eccentric trajectories during head switching, a head position control method performs feed forward control for a plurality of disk surfaces by application of the eccentricity correction current of respective heads, and when switching heads, predicts the velocity fluctuation or current step differential between heads from the eccentricity correction current, and thus corrects the control system to eliminate velocity fluctuation and current step differential. | 6 |
RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 114,324, filed Oct. 28, 1987, now U.S. Pat. No. 4,879,168 of McCullough et al, entitled "Flame Retarding and Fire Blocking Fiber Blends".
FIELD OF THE INVENTION
The present invention relates to foam seat cushion coverings and upholstering having flame retarding and fire barrier characteristics. More particularly, the invention is concerned with foam seat cushions with non-woven coverings comprising a blend of carbonaceous fibers with a binder, and structures containing such coverings.
BACKGROUND OF THE INVENTION
Both government and industry have conducted extensive research into developing fabrics for the seat cushions of airplanes that would either be non-flammable or at least retard the propagation of a fire. In conjunction with finding an effective material to act as a fire barrier, consumer considerations require that any such materials be functional, aesthetically acceptable and reasonably priced. Suitable barriers do exist such as needle punched aramids, however, these barriers are difficult to cut and sew, heavy and often provide less than desired comfort.
Unfortunately, past efforts to develop a suitable fire barrier have not been very effective. Thus, even fabrics that will not ignite from a smoldering cigarette and that are considered to be class 1 fabrics under the UFAC upholstery fabric classification test will burn when placed in contact with an open flame. Consequently, this leads to the ignition of an underlying foam cushion.
Inherently, flame-retardant fibers are well-known to those skilled in the art. These fibers, known as matrix fibers, though useful because of their flame-retardant qualities, are not strong enough to form their own fabrics, tend to have a non-uniform composition, are not succeptible of being easily dyed, and, in general, are not alone suitable for production into fabrics to form coverings for seat cushions. On the other hand, conventional natural and synthetic fibers (staple fibers) which are alone suitable for production into seat cushions are not inherently flame-retardant.
Many types of flame resistant fabrics, i.e., fabrics which are self-extinguishing when the ignition source is removed, have been provided by the prior art. For example, fabrics of normally flammable fibers, e.g., cotton, rayon, etc. have been treated with innumerable flame resistant surface coating compositions. More recently, flame resistant fabrics have been prepared from either normally flammable synthetic fibers, e.g., rayon, polyolefins, polyesters, acrylics, etc., which have been spun with flame retardant additives or from other synthetic fibers which are spun from polymers which are inherently flame resistant, PG,4 e.g., polyvinylchloride, polytetrafluoroethylene, polymetaphenyleneisophthalamide. Although such flame resistant fabrics have found substantial application in carpets, draperies, upholstery, etc. and also in garments such as costumes, sleepwear, etc. where flame propagation from inadvertently applied ignition sources is to be avoided, in general, such fabrics are not satisfactory for upholstery or seat cushion covering, especially for airplanes, since they exhibit shrinkage or rapid break open on exposure to intense heat fluxes. The art has provided a limited number of super-high-temperature organic polymeric fibers, e.g., polybenzimidazoles, polyoxadiazoles, polyparaphenylene terephthalamide and certain heat-treated/cyclized acrylic, which in fabric form can survive intense thermal fluxes, at least for a worthwhile interval. However, such fabrics also exhibit one or more negatives, such as limited durability (poor abrasion resistance, low flex life) and poor dyeability. In some instances the polymer used for the fiber of the fabric is inherently highly colored.
It is not sufficient that the fabric merely be flame resistent and possess abrasion resistance. To be completely acceptable, the fabric must also be lightweight, conformable, nonscratchy, durable in normal use, dyeable, etc. in order that the seat covering made therefrom will be sufficiently comfortable and aesthetically attractive.
European Patent Application 0199567 of McCullough, et al discloses non-linear carbonaceous fibers which are used in the structures and fabrics of the present invention.
The carbonaceous fibers of the invention according to the test method of ASTM D 2863-77 have a LOI value greater than 40.
The term "Reversible Deflection" as used herein applies to a helical or sinusoidal compression spring. Particular reference is made to the publication "Mechanical Design--Theory and Practice", MacMillan Publ. Co., 1975, pp 719 to 748; particularly Section 14-2, pages 721-24.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided lightweight flame retarding and flame shielding or blocking non-woven fabric structures for foam seat cushion coverings comprising about 25-75% by weight of linear and/or non-linear carbonaceous fibers having a carbon content of at least 65%, derived from heat set stabilized polymeric fibers or a pitch based fiber and a binder. The seat covering structure advantageously comprises an intimate blend of a suitable binder, preferably polyester, and non-flammable linear or non-linear carbonaceous filaments having a reversible deflection ratio of greater than 1.2:1, preferably greater than 2.0:1, and an aspect ratio (1/d) greater than 10:1. The non-linear fibers have been found more advantageous since they provide considerable porosity which inhibits the spread of fire. Both linear and non-linear carbonaceous fibers have a LOI value greater than 40.
Furthermore, it has been surprisingly found that the carbonaceous fibers when intimately blended with a polyester results in a synergistic effect with respect to fire blocking and fire retarding properties as well as holding back molten urethane of the seat cushion when intense heat and flame is applied to the covered cushion. The fabric structure of the invention is especially used to prevent the sideways propagation of fire.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the invention, it has been surprisingly discovered that a foamed seat cushion can be provided with a non-woven covering comprising carbonaceous polymeric fibers having an LOI value of greater than 40 which are intimately blended with a suitable binder which provides a synergistic improvement in the fire retarding and fire blocking characteristics of the resulting structure. Even more significant results are achieved when the carbonaceous fibers are non-linear fibers, have a reversible deflection ratio of greater than 1.2:1 and an aspect ratio (1/d) greater than 10:1. Both the linear and non-linear fibers can be utilized in connection with the present invention. When the carbonaceous fibers are non-linear the gap between the fibers provides the porosity in the event of fire which suppresses smoldering. It is understood that the greater the amount of non-linear carbonaceous fibers which are utilized, the better will be the reforming and fire retarding characteristics of the structure.
The non-linear carbonaceous fibers which are utilized may have a sinusoidal and/or a coil-like configuration depending upon the ultimate use of the fibers. The acrylic derived carbonaceous fibers have a nitrogen content in which the nitrogen content is between 18 and 20% are especially useful for fabrics making skin contact with the wearer.
The fabrics may comprise a blend of all natural, all synthetic or a combination of both together with the carbonaceous fibers.
The natural fibers wherein the synergistic effect is found when used in a blend with the carbonacecus fibers of the invention include cotton, wool, flax and silk.
The synthetic fibers which can be utilized to form a blend with the carbonaceous fibers of the present invention include polyolefins, for example, polyethylene, polypropylene and the like, polyvinyl chloride, polyvinyl alcohol, polyesters, polyacrylonitrile, polyacrylates, polycarbonate, cellulosic products, ionomers, DACRON (Trademark), KEVLAR (Trademark), and the like. It is to be understood of course, that a blend of natural and/or synergistic fibers with the carbonaceous fibers may be used.
The binders utilized in the present invention comprise any of the conventional thermal bonding fibers such as Kodel 410 of Eastman Chemical, a polyethylene binder having a flow point of 8 denier at 88° C., Dacron D171W of E.I. du Pont de Nemours, PRIMACOR 400 (trademark of The Dow Chemical Company for low melting polyethylene acrylic acid copolymer fibers, and the like.
Exemplary of the products which can be structures of the present invention are set forth in the following examples. It is understood that the percentages referred to herein relate to percent by weight.
EXAMPLE 1
A. Battings were made by blending an appropriate weight percent of each respective opened fiber in a blender/feed section of a sample size 40"Rando Webber Model D manufactured by Rando Machine Corp. of Macedon, N.Y. The battings produced typically were 1 inch (2.54 cm) thick and had bulk densities in a range of from 0.2 to 1 lb/cc ft. The battings were thermally bonded by passing the Rando batting on a conveyor belt through a thermal bonding oven at a temperature of about 200° C. together with a low melting resistant polyester. The result was a fire resistant non-woven fabric which could be utilized for coverings for the foam of airline seat cushions.
EXAMPLE 2
Non-Flammability Test
The non-flammability of the fabric of the invention has been determined following the test procedure set forth in 14 CFR 25.853(b), which is herein incorporated by reference. The test was performed as follows:
A minimum of three 1"×6"×12"(2.54 cm ×15.24 cm ×30.48 cm) specimens comprised of 70% carbonaceous fiber -25% polyester -5% wool were conditioned by maintaining the specimens in a conditioning room maintained at 70 degrees ±5 degrees F. temperature and 50% ±5% relative humidity for 24 hours preceding the test.
Each specimen was supported vertically and exposed to a Bunsen or Turill burner with a nominal I.D. tube adjusted to give a flame of 11/2 inches (3.81 cm) in height by a calibrated thermocouple pyrometer in the center of the flame was 1550 degrees F. The lower edge of the specimen was 3/4 inch (1.91 cm) above the top edge of the burner. The flame was applied to the center line of the lower edge of the specimens for 12 seconds and then removed.
Pursuant to the test, the material was self-extinguishing. The average burn length did not exceed 8 inches (20.32 cm). The average after flame did not exceed 15 seconds and there were no flame drippings.
EXAMPLE 3
A. Battings were made by blending an appropriate weight percent of each respective opened fiber in a blender/feed section of a sample size 12" Rando Webber Model B manufactured by Rando Machine Machine Corp. of Macedon, N.Y. The battings produced typically were 1 inch (2.54 cm) thick and had bulk densities in a range of from 0.4 to 6 lb/cc ft (6.4 cm to 96 kg/cc m 3 ). The battings were thermally bonded by passing the Rando batting on a conveyor belt through a thermal bonding oven at a temperature of about 300° C.
Flammability tests were run in a standard apparatus as cited in FTM 5903 according to the procedure of FAR 25.853b which references FTM 5903. The results are shown in the following Table I:
TABLE I__________________________________________________________________________ Sample Burn After Flame Drop PassSample No. Composition % Wt. Length (in.) Flame (Sec.) Time (Sec.) or Fail__________________________________________________________________________ 1 NCF/PEB/PE 10/20/70 2/1/1 0/0/0 0/0/0 passed 2 NCF/PEB/PE 20/20/60 .75/.75/.75 0/0/0 0/0/0 passed 3 NCF/PEB/PE 25/20/55 .75/.75/.75 0/0/0 0/0/0 passed 4 NCF/PEB/PE 30/20/50 .5/.5/.5 0/0/0 0/0/0 passed 5 NCF/PEB/PE 40/20/40 .5/.5/0 0/0/0 0/0/0 passed 6 NCF/PEB/PE 5/20/75 complete 20 sec. 0/0/0 failed 7 NCF/PEB/PE 50/20/30 0/0/0 0/0/0 0/0/0 passed 8 OPF/PEB/PE 10/20/70 complete 20 sec. 0/0/0 failed 9 LCF/PEB/PE 50/20/30 .25/.25/.25 0/0/0 0/0/0 passed10 NCF/PEB/cotton 10/10/80 .5/.5/.5 0/0/0 0/0/0 passed11 Nomex ™/PEB/PE 20/20/60 complete 38 sec. 0/0/0 failed12 Nomex ™/PEB/PE 50/20/30 complete 30 sec. 0/0/0 failed13 NCF/PEB/Cotton 10/15/75 .75/.75/.5 0/0/0 0/0/0 passed14 NCF/PEB/Cotton 5/15/80 12 14 -- failed15 NCF/PEB/PE 5/20/75 12 195 0/0/0 failed16 NCF/PEB/PE 7.5/20/72.5 2/10/2 0/7/0 0/0/0 borderline17 LFC/PEB/Cotton 25/15/60 1/1.25/1 0/0/0 0/0/0 passed18 OPF/PEB/Cotton 50/15/35 14 3 sec. 0/0/0 failed19 NCF/PEB/Cotton 20/15/65 .75/.75/.75 0/0/0 0/0/0 passed20 NCF/PEB/Wool 5/15/80 10 5 0/0/0 failed21 NCF/PEB/Wool 10/15/75 1.25/1/1 0/0/0 0/0/0 passed22 NCF(sc)/PEB/Cotton 20/15/65 1/1/.75 1/.5/0 0/0/0 passed23 OPF/PEB/PE 50/20/30 12 8/8 0/0/0 failed__________________________________________________________________________
NCF=non-linear carbonaceous fiber
LCF=linear carbonaceous fiber
LCF(SC)=linear carbonaceous fiber with small amplitude crimp
PEB=8 denier polyester binder fiber of 410 KODEL (Trademark)
PP=polypropylene
PE=6 denier 2" staple Dupont DACRON (Trademark) 164 FOB polyester
Cotton=non-treated 11/2" cotton
OPF=stabilized polyacrylonitrile fiber
NOMEX=trademark of an aramid fiber available from E.I. de Pont & Co.
The above table shows surprisingly that use of as little as 7.5% by weight of carbonaceous fibers in the blends resulted in substantially no after flame when the flame source was removed and no flame drippings.
The battings with sufficient binder and under pressure could be made into non-woven fabrics which are suitable for use in the present invention.
Following the procedure of Example 3 a similar tests were performed and the results are shown in the following Table II.
TABLE II__________________________________________________________________________Sample Sample Densification Burn After Flame PassNo. Comp. Composition Method Length (in.) Flame (sec.) Drop (sec) or Fail__________________________________________________________________________1 NCF/PEB/PE 30/20/51 NP 1.5/1.5/1 0/0/0 0/0/0 passed2 NCF/PEB/PE 30/20/50 PS .5/.75.5 0/0/0 0/0/0 passed3 Nomex ™/PEB/PE 20/20/60 NP total 30 sec. 2 sec. failed4 Nomex ™/PEB/PE 50/20/30 NP total 40 sec. -- failed5 NCF/PEB/PE 20/20/60 NP 2/2/2 0/0/0 0/0/0 passed6 NCF/PEB/PE 20/20/60 PS 1.5/1.5/1.5 0/0/0 0/0/0 passed7 NCF/PEB/Cotton 30/15/55 NP 1/1/1 0/0/0 0/0/0 passed8 NCF/PEB/Cotton 30/5/55 -- .5/.5/.5 0/0/0 0/0/0 passed9 NCF/PEB/Cotton 30/15/55 NP .75/.75/.75 0/0/0 0/0/0 passed10 NCF/PEB/Cotton 30/15/15 PS 1.25/1.5/1.25 0/0/0 0/0/0 passed11 Kevlar ™/PEB/PE 50/20/30 -- .5/.5/.5 0/0/0 0/0/0 passed12 Kevlar ™/PEB/PE 50/20/30 NP 3.5/3/3.5 0/0/0 0/0/0 passed13 Kevlar ™/PEB/PE 50/20/30 PS 1.25/1.5/1.5 0/0/0 0/0/0 passed14 Kevlar ™/PEB/PE 20/20/60 -- 12 complete burn failed15 Kevlar ™/PEB/Cotton 50/15/35 -- 15/.5/.5 0/0/0 0/0/0 passed16 Kevlar ™/PEB/Cotton 50/15/35 NP .5/.5/.5 0/0/0 0/0/0 passed17 Kevlar ™/PEB/cotton 50/15/35 PS .75/.75/.75 0/0/0 0/0/0 passed__________________________________________________________________________ NP = needle punched at 100 PS Pin Sonic Thermally Bonded in diamond pattern
EXAMPLE 4
Flammability tests were conducted in accordance with FAA approve, "Airline Fabricare Flame Blocking Test Procedures" dated 9, January 1985.
To pass this test the average percentage weight loss may not exceed 10%; the char length (burn across) must be less than 17 inches; and at least two of the three specimens must pass the tests in all respects.
A. A standard HR fire resistant urethane foam (1,6 lb/ft 3) was covered with a standard blocking layer (4 oz/y.d 2 and a non-woven fabric consisting of 20% carbonaceous fibers of the invention and 80% polyester binder composed of a 3:1 ratio of high melt polyester binder to low melt polyester binder. The cushions were conditioned for 24 hours and the flames were set for 2 minutes.
______________________________________ Test 1 Test 2 Test 3______________________________________initial wt. 21.84 21.83 21.84weight/cushions 26.93 26.98 27.07Initial system wt. 5.09 5.15 5.23Final wt. 26.51 26.80 26.81weight loss 0.42 0.18 0.26% wt. loss 8.25 3.50 4.97char length 15.0 10.0 12.0______________________________________B. Vertical burn test results.Dress Cover Blocking Layer Burn Time Burn Length Burn Time Burn Length______________________________________Test 1 1.4 2.3 0.0 0.0Test 2 1.2 2.3 0.0 0.0Test 3 0.8 2.0 0.0 0.0Average 1.1 2.2 0.0 0.0______________________________________
Conclusions
All specimens passed the test. | A non-linear fire retarding and fire blocking covering for a foam seat cushion structure comprising an intimate blend of a binder and 25-75% by weight of fibers comprising heat set carbonaceous fibers having a LOI value greater than 40, said carbonaceous fibers being derived from heat treated stabilized polymeric fibers or pitch based fibers. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application No. 61/053,581, filed May 15, 2008, which is incorporated herein by reference.
FIELD
This invention relates to positional fixation and more particularly relates to orthopedic fixation devices.
BACKGROUND
The setting and immobilization of bone fractures with simple splints and slings has been practiced since ancient times. Modem biomedical engineering has yielded increasingly advanced orthopedic fixation technology, including various internal and external devices, such as pins, braces, plates, and screws. Many of these devices are temporary, and require removal after surgery or at any of various times throughout the healing process. Some devices such as internal screws are often left in place indefinitely, due to the cost, potential complications, and difficulty of removing them.
Typically, orthopedic hardware is removed at some time following surgery for various reasons. For example, a fastener embedded in bone can act as a stress riser, which may increase the risk of an undesired fracture in the bone proximate the fastener location. Additionally, over time, the position of a fastener can shift away from the initial embedded position, which may result in an infection or other negative side effect. At the very least, an un-removed fastener may simply cause discomfort, such as by conducting cold temperatures, or creating pain and irritation in the tissue surrounding the fastener. Although less likely, tan un-removed fastener may result in the potential inconvenience associated with metal detector false alarms.
In addition to potentially negative consequences caused by leaving hardware fixed in a patient's bone, some negative effects may be caused during the installation of the hardware. For example, a fastener may become damaged during the process of insertion, such as stripping the head or breaking the head off entirely. Such damage to the head can make further insertion and/or extraction of the fastener highly problematic.
The nature of bone itself also presents some challenges. As the bone heals, it tends to encase the fastener more tightly, which can increase the torque required to loosen the fastener from the bone. The bone may also encroach upon the head of the fastener making it difficult to access. Another problem arises from the hollow nature of bones. When removing a screw, once the threaded portion has been unscrewed from the distal cortex of the bone, there may be insufficient resistance offered by the screw head to keep the driver engaged. Moreover, even if the screw can be extracted to the point where the proximal end of the threaded portion comes into contact with the proximal cortex of the bone, the bone may have grown tightly around the shank, which can impede further progress. Accordingly, there may be insufficient resistance to keep the driver engaged in the head for the threads to bite.
Other challenges analogous to those discussed above may also exist in non-medical positional fixation applications, such as applications involving materials such as wood, metal, and plastic, or any applications where a reliable and minimally invasive apparatus, system, or method for insertion and/or removal of a fastener is desired.
SUMMARY
From the foregoing discussion, it should be apparent that a need exists for an apparatus, system, and method for the insertion and extraction of orthopedic fasteners which are problematically positioned or otherwise compromised. Beneficially, such an apparatus, system, and method would also be useful in non-medical applications.
The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available positional fixation instruments. Accordingly, the present invention has been developed to provide an apparatus, system, and method for positional fixation fastener operation, particularly extraction, which overcome at least one, many, or all of the above-discussed shortcomings in the art.
Generally, an apparatus is provided that tightens around a fastener, locks the fastener into position, and unlocks and releases the fastener when the operation is complete. The apparatus can include a collet with a proximal end and a distal end. In some embodiments, the distal end can be compressible or expandable to conform to a proximal end of a fastener. The proximal end of the collet is received by a chuck body. The apparatus can also include a handle configured to receive, such as in a seated arrangement, a proximal end of the chuck body. The apparatus may include a closing mechanism coupled to the handle. The closing mechanism can be operable to cause the collet to be tightened against the handle, which, in some embodiments, causes a compressible distal end of the collet to conform to the proximal end of the fastener.
In one embodiment, the closing mechanism may include a shaft longitudinally disposed within the handle for drawing the collet into the aperture of the chuck body so as to compress the collet around the proximal end of the fastener. A threaded connection between the shaft and a knob at a proximal end of the handle allows the collet to be tightened when the knob is turned in one direction, typically clockwise, and loosened when the knob is turned in an opposite direction.
In certain implementations, the closing mechanism includes a lever connected to a distal end of the handle at a first pivot joint, a locking member including a distal end connected to the lever at a second pivot joint proximal to the first pivot joint, and a shaft longitudinally disposed within the handle. The shaft can be coupled to the proximal end of the collet at a distal end portion of the shaft and coupled to a proximal end of the locking member at a third pivot joint proximal to the second pivot joint.
In a further implementation, the closing mechanism may also include a lever-operated linkage. The linkage may be comprised of a lever connected to a distal end of the handle by a first pivot joint, a locking member having a distal end connected to the lever by a second pivot joint proximal to the first pivot joint, and a proximal end connected through a channel in the side of the handle to the shaft by a third pivot joint. When the lever is depressed toward the handle, a proximal moment of force along the shaft draws the collet into the chuck body in a manner similar to the tightening of the above-described knob. Thus, the closing mechanism may comprise either the lever or the knob or both. When both are present, the knob permits an adjustment of the position of the third pivot joint to optimize the degree of force required to close the lever consistent with the strength of the operator and the structural integrity of the mechanism.
In the fully closed position, the lever causes the second pivot joint to descend deeper into the channel than a line between the first pivot joint and the third pivot joint, thus diverting a small amount of the compression force between the chuck body and the collet to create a downward moment of force locking the lever against the handle. To unlock the mechanism, the lever is lifted away from the handle, relaxing the proximal force along the shaft and loosening the collet by extending it out of the chuck body.
An ergonomic advantage may be obtained by allowing the lever to recess into the channel in the closed position, thereby permitting a more comfortable grip while using the instrument, as well as having the proximal end of the lever extend beyond the proximal end of the handle to facilitate lifting the lever out of the closed position.
According to one implementation, the collet and even the chuck body may be disposable. For example, biological contamination may prevent reuse of these components, even if treated, such as in an autoclave. Moreover, in some implementations, the apparatus may further include a centrally aligned longitudinal bore through all of the apparatus components to admit a wire for purposes of alignment with a cannulated fastener.
The apparatus, in one embodiment, is configured with a plurality of longitudinal slits in the compressible distal end of the collet, thereby forming a plurality of jaws. In some implementations, the jaws are able to flex outward to capture larger fasteners and flex inward under the compression force against the chuck body, thereby enabling a tighter grip on the proximal end of the fastener.
The apparatus is further configured, in one embodiment, with a cutting edge on the distal end of the collet. The cutting edge is able to remove material from around the proximal end of the fastener within a medium composed of the material, such as bone growth that has encroached upon it.
A system of the present invention is presented to operate compatibility with the wide variety of fasteners that exist or may be developed in the future. In particular, the system, in one embodiment, includes a plurality of interchangeable collets, each snugly conforming to the maximum perimeter of proximal end of a corresponding type or size of fastener. A special collet may even be provided to fit the shank of a broken fastener. In one specific implementation, a system for installing and removing fasteners from bone tissue includes a plurality of fasteners each comprising a proximal end portion having a different size. The system also includes a plurality of interchangeable collets each comprising a proximal end portion and a distal end portion. The distal end portion can be conformable to a perimeter of the proximal end portions of the plurality of fasteners. The system also includes a chuck body configured to receive the proximal end portion of each of the plurality of interchangeable collets and a handle configured to receive a proximal end of the chuck body. Additionally, the system includes a closing mechanism coupled to the handle. The closing mechanism includes a first tightening portion operable to partially conform the distal end portion of a respective collet to the perimeter of the proximal end portion of a respective fastener and a second tightening portion operable to further conform the distal end portion of the respective collet to the perimeter of the proximal end portion of the respective fastener.
In certain implementations, the first tightening portion comprises a rotatable knob and the second tightening portion comprises a pivotable lever. Rotation of the knob can cause the chuck body to apply a first force to the distal end portion of the respective collet and pivoting the lever can cause the chuck body to apply a second force to the distal end portion of the respective collet where the second force is greater than the first force
A method of the present invention is also presented for positional fixation. In one embodiment, the method substantially includes the actions necessary to carry out the functions of the apparatus and system described herein. In one particular embodiment, a method for securing a fastener includes removably positioning a chuck body within a handle, removably positioning a proximal end of a collet within the chuck body, and removably positioning a fastener within a compressible distal end of the collet. The method also includes adjusting a tightening portion of a closing mechanism coupled to the handle and collet to urge the distal end of the collet against the chuck body and partially compress the distal end of the collet against the fastener. Further, the method includes adjusting a locking portion of the closing mechanism to further urge the distal end of the collet against the chuck body and further compress the distal end of the collet against the fastener.
In some implementations of the method, the tightening portion includes a knob coupled to the collet via a shaft. Adjusting the tightening portion can then include rotating the knob to urge the collet and shaft in a proximal direction. In other implementations, the locking portion includes a lever coupled to the collet via a shaft. Adjusting the locking portion can then include pivoting the lever toward the handle to urge the collet and shaft in a proximal direction.
In one embodiment, a method includes accessing a material amenable to positional fixation, installing the collet, fitting the fastener into the collet, tightening and locking the fastener into place, extracting the fastener by means of the handle, and then unlocking, loosening, and separating the fastener from the instrument. The method also may include inserting the fastener, particularly if the head is damaged, or if the torque required to fully insert a fastener, such as a screw, might strip the head if a conventional screwdriver were used. In a further embodiment, the method includes discarding the collet if it is not reusable, such as due to biological contamination.
Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.
Furthermore, the features, advantages, and characteristics of the apparatus, system, and method described herein may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.
These features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only certain illustrative embodiments and are not therefore to be considered to be limiting of its scope, further embodiments of the invention will be described and explained with additional specificity and detail through the use of the specification, claims, and accompanying drawings, in which:
FIG. 1 is a perspective view illustrating one embodiment of a positional fixation instrument in accordance with the present invention;
FIG. 2 is a side view further illustrating the instrument of FIG. 1 holding a fastener;
FIG. 3 is an exploded side view of the instrument and fastener of FIG. 2 ;
FIG. 4 is a front view of the instrument of FIG. 1 ;
FIG. 5 is a rear view of the instrument of FIG. 1 ;
FIG. 6 is a cross-sectional side view of the instrument of FIG. 1 taken along the line 6 - 6 of FIG. 4 and showing a closing mechanism in an open position;
FIG. 7 is a cross-sectional side view of the closing mechanism of FIG. 6 in a closed position;
FIG. 8 is a detailed perspective view of a chuck body according to one embodiment;
FIGS. 9A-9C are a detailed perspective view of a plurality of collets according to several embodiments;
FIGS. 10A and 10B are a detailed cross-sectional side view taken along the line 10 A- 10 A of FIG. 10B and a front view, respectively, of a collet according to a first embodiment;
FIGS. 11A and 11B are a detailed cross-sectional side view taken along the line 11 A- 11 A of FIG. 11B and a front view, respectively, of a collet according to a second embodiment;
FIGS. 12A and 12B are a detailed cross-sectional side view taken along the line 12 A- 12 A of FIG. 12B and a front view, respectively, of a collet according to a third embodiment;
FIGS. 13A and 13B are a side view and front view, respectively, of a collet according to a fourth embodiment;
FIGS. 14A and 14B are a side view and front view, respectively, of a collet according to a fifth embodiment;
FIGS. 15A and 15B are a detailed cross-sectional side view taken along the line 15 A- 15 A of FIG. 15B and a front view, respectively, of a collet according to a sixth embodiment; and
FIG. 16 is a flow diagram illustrating one embodiment of a method for employing the instrument in accordance with the present invention.
DETAILED DESCRIPTION
Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. Furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. Additionally, one skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific details described herein, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.
The schematic flow chart diagrams included herein are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of one embodiment of the presented method. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Additionally, the format and symbols employed are provided to explain the logical steps of the method and are understood not to limit the scope of the method. Although various arrow types and line types may be employed in the flow chart diagrams, they are understood not to limit the scope of the corresponding method. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the method. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted method. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown.
Referring to FIG. 1 , one embodiment of a positional fixation instrument 100 in accordance with the present invention is shown having an interchangeable collet 102 or chuck tip. The collet 102 is received by a chuck body 104 which is seated in a handle 106 and held in place by a set screw 108 . The collet 102 may be tightened by adjusting a tightening portion and further tightened or locked in place by adjusting a locking portion. The tightening portion includes a knob 110 and is adjusted by turning the knob 110 in one direction, typically clockwise, to draw the collet 102 into the chuck body 104 . The collet 102 may be opened and loosened by turning the knob 110 in an opposite direction, which extends the collet 102 out of the chuck body 104 . The locking portion includes a lever 112 and locking member 114 . The collet 102 maybe further tightened and locked by depressing lever 112 , causing a locking member 114 to descend into a channel 116 along the side of the handle 106 , and may be unlocked by lifting the lever 112 .
FIG. 2 is a side view further illustrating the instrument 100 holding a fastener 202 . The lever 112 is in a fully closed and locked position, causing the collet 102 to close around and tightly grip the fastener 202 . Note that in this configuration the lever 112 fits within the channel 116 , thus providing an ergonomic handhold for operation of the instrument 100 in positioning the fastener 202 .
FIG. 3 is an exploded side view of the instrument 100 and the fastener 202 . In one embodiment, the fastener 202 is a screw, having a threaded portion 302 connected via a shank 304 to a proximal end 306 . Alternative embodiments of the fastener 202 may include a bolt, a pin, a rivet, a nail, a staple, an anchor, or some other fastener. The proximal end 306 as illustrated is a uniform sized head. Further embodiments of the proximal end 306 may include a non-uniform sized head or a headless fitting. In one embodiment, the threaded portion 302 may have a distal self-tapping or self-drilling end 308 to facilitate insertion of the fastener 202 by turning it in one direction, typically clockwise, and a proximal end 310 opposite the distal self-tapping end.
The collet 102 has a compressible distal end 312 which is designed to fit over and snugly conform in shape to the proximal end 306 of the fastener 202 . In some embodiments, the collet 102 is configured to fit the proximal end 306 of a respectively sized and specific type of fastener. However, in other embodiments, the range of compression of the collet 102 allows the collet to fit several differently sized and/or types of fasteners. For example, in one specific implementation, the collet 102 is configured to fit over and snugly conform in shape to proximal ends 306 of fasteners 202 sized between about 6 mm and about 4.3 mm. Of course, in other implementations, the collet 102 can be sized to conform to proximal ends 306 of fasteners 202 within any of various size ranges. In some instances, larger proximal ends 306 may initially cause the compressible distal end 312 of the collet 102 to expand as the collet is placed about the proximal end to accommodate the larger size of the proximal end. However, tightening of the collet to the hand tool will cause the “expanded” compressible distal end to at least slightly compress to ensure a tight fit around the proximal end. A collet 1022 configured to expand as the collet is tightened to the hand tool is described below in relation to FIGS. 15A and 15B . In another embodiment, a specialized collet 102 may also be provided to fit a specifically sized shank 304 or differently sized shanks of the fastener 202 in the event that the proximal end 306 has broken off of the fastener.
The collet 102 is installed by inserting its threaded proximal end 314 through the chuck body 104 into a shaft 316 and screwing it firmly in place. The chuck body 104 is seated in the handle 106 and held in place by tightening the set screw 108 into a set screw hole 318 (set screw 108 not shown in FIG. 3 ). In the illustrated exploded view, part of the shaft 316 is visible through the set screw hole 318 . As the shaft 316 is retracted into the handle by means of the knob 110 and/or the lever 112 , the collet 102 is in turn drawn into the chuck body 104 , thereby compressing the compressible distal end 312 and tightening its grip around the corresponding proximal end 306 of the fastener 202 .
FIG. 4 is a front view of the instrument 100 , with the chuck body removed to better reveal its internal structure. As shown with the lever 112 in the closed position, the handle 106 is roughly cylindrical in shape, with the lever mount 402 on top. In alternative embodiments, the handle can have any of various shapes, such as ovular, triangular, elliptical, and hexagonal. The chuck seat 404 is countersunk into the handle 106 to receive the chuck body 104 as it encircles the shaft 316 . A threaded hole 406 is provided in the shaft 316 to accept the threaded proximal end 314 of the collet 102 . A central bore 408 runs the length of the instrument 100 to allow passage of a guide wire (not shown) as used in conjunction with a cannulated fastener. Accordingly, the collet 102 , chuck body 104 , handle 106 , shaft 316 , and knob 110 include central bores that collectively define the bore 408 .
FIG. 5 is a rear view of the instrument 100 , providing a clear illustration of the channel 116 in line with the lever 112 . It can be seen that the knob 110 is hollow, being connected to the shaft 316 , thereby retracting or extending the collet 102 via the threaded hole 406 in the shaft 316 when the knob 110 is respectively turned in one direction or another. The central bore 408 is also visible in this view, since it passes all the way through the shaft 316 and emerges into the hollow knob 110 .
As shown in FIG. 6 , the knob 110 of instrument 100 is coupled to the shaft 316 via an extended portion 602 . In the illustrated embodiment, the knob 110 , shaft 316 , and extended portion 602 form a one-piece monolithic construction with each other. The handle 106 includes a central bore 140 having a first proximal portion 142 coaxial with a second distal portion 144 . The first proximal portion 142 is sized to matingly receive the shaft 316 and the second distal portion 144 is sized to matingly receive the extended portion 602 of the knob 110 . The shaft 316 and extended portion 602 are rotatable within the first proximal and second distal portions 142 , 144 , respectively. Preferably, the first proximal portion 142 retains the shaft is substantially coaxial alignment with the first proximal portion and the second distal portion 144 retains the extended portion is substantially coaxial alignment with the second distal portion. The lever 112 is connected to the handle 106 via a first pivot joint 604 . A second pivot joint 606 connects the lever 112 to a distal end of the locking member 114 . A proximal end of the locking member 114 is in turn connected to the extended portion 602 of the knob 110 via a third pivot joint 608 . The chuck seat 404 and central bore 408 are also shown in this view.
The proximal end of the locking member 114 is secured to the third pivot joint 608 via a shackle member 620 coupled to the shaft 316 . The shackle member 620 is configured to ensure that the third pivot joint 608 moves axially when the shaft 316 moves axially, and that the shaft 316 is rotatable relative to the third pivot joint. The shackle member 620 includes two space-apart tabs 622 extending vertically away from the shaft 316 and a sleeve portion 624 wrapped about at least half of the periphery of the shaft. The proximal end of the locking member 114 is positioned between the tabs 622 and secured to the tabs by extending the pivot joint 608 through apertures in the tabs and locking member. When secured to the proximal end of the locking member 114 , the shackle member 620 is configured to retain the third pivot joint 608 in a vertically fixed location (as shown in FIG. 6 ) relative to the shaft 316 , but allow the shaft to rotate relative to the shackle member. The shackle member 620 is prevented from moving axially or horizontally (as shown in FIG. 6 ) relative to the shaft 316 through use of a stop 626 secured to and fixed relative to the shaft and extended portion 602 . More specifically, the shackle member 620 is effectively sandwiched between the stop 626 and the extended portion 602 of the knob 110 . The stop 626 prevents movement of the shackle member 620 in a first axial direction relative to the shaft 316 and the extended portion 602 prevents movement in a second axial direction opposite the first relative to the shaft. The stop 626 transfers collet disengaging thrust loading from the lever 114 to the shaft 316 when releasing a fastener from the collet and the extended portion 602 transfers collet engaging thrust loading from the lever 114 to the shaft 316 when securing a fastener in the collet. In one specific embodiment, the stop 626 is an external snap ring engaged within a recess 628 formed in the outer surface of the shaft 316 .
Referring to FIG. 7 , as the lever 112 is depressed, the second pivot joint 606 is brought directly into line with the first pivot joint 604 and the third pivot joint 608 to drive the shaft 316 and knob 110 in a proximal direction, i.e., distal-to-proximal direction, as indicated by directional arrow 610 . Movement of the shaft 316 and knob 110 in the proximal direction after the collet has been tightened against the chuck body 104 using the knob results in the application of a maximal compression force between the compressible distal end 312 of the collet 102 and the chuck body 104 as described above. When the lever 112 is in the fully closed position as shown, the second pivot joint 606 is substantially aligned with, but slightly below a line between, the first pivot joint 604 and third pivot joint 608 , thus diverting a small amount of the maximal compression force into a downward moment of force which holds the lever 112 down and locks the closing mechanism 600 in the fully closed position. Note that the lever 112 extends proximally beyond the handle 106 , providing convenient access for lifting it to unlock the closing mechanism 600 .
As shown in FIG. 8 , a central bore 806 runs a length of the chuck body 104 from a distal end 810 to a proximal end 812 . The chuck body 104 includes a collet engaging portion 802 extending from the distal end 810 to a location intermediate the distal end and proximal end 812 . The central bore 806 along the collet engaging portion 802 is inwardly tapered in a distal end to proximal end direction. The taper of the central bore 806 approximately corresponds with a distal-to-proximal taper of the outer surface of the compressible distal end of a collet in an uncompressed state (see, e.g., distal end 312 of collet 102 C of FIG. 9C ). When initially assembled, the corresponding tapered surfaces of the central bore 806 and distal end 312 of the collet engage each other such that the distal end 812 of the collet 102 C matingly seats within the central bore. As the lever 112 is closed, the compressible distal end 312 of the collet slides along the central bore 806 of the collet engaging portion 802 in the distal-to-proximal direction relative to the central bore such that the wall of the central bore exerts an inwardly directed force against the compressible distal end of the collet. The inwardly directed force causes the compressible distal end 312 of the collet 102 C to gradually deform and radially compress against the proximal end 306 of the fastener 202 . The tapered nature of the engaging surfaces distributes the inwardly directed force evenly across the distal end 312 of the collet 102 C to facilitate ease in compressing the distal end against the fastener. The tapered surface of the central bore 806 is also configured to engage and facilitate compression of a distal end of a collet having a curved or arcuate shaped outer surface (see, e.g., distal end 312 of collet 102 of FIG. 3 and distal end 312 of collet 102 B of FIG. 9B ).
The chuck body 104 also includes a key or spline 820 extending inwardly from the inner surface of the central bore 806 in a direction parallel to the axis of the chuck body. The key 820 can extend between the distal end 810 to a location intermediate the distal end 810 and the proximal end 812 . The key 820 is configured to engage a keyway or slot 822 formed in the collet and extending in a direction parallel to the axis of the collet (see, e.g., collet 102 C of FIG. 9C ). In other words, as the collet is inserted into the chuck body 104 , the key 820 is positioned and retained within the keyway 822 . Engagement between the key 820 and keyway 822 reduces, restricts, or prevents rotation of the collet relative to the chuck body 104 . Additionally, the key 820 and keyway 822 are axially aligned when the collet is properly seated in the chuck body. The axial alignment between the key and keyway allows for relative movement between the collet and chuck body in the axial or lengthwise direction. Although in the illustrated embodiments, the key 820 is formed in the central bore 806 of the chuck body 104 and the keyway is formed in the collet 102 C, in other embodiments, the key can be formed in the collet and the keyway can be formed in the central bore.
In alternative embodiments, configurations other than a key-keyway or spline configuration can be used to reduce, restrict, or prevent relative rotation between the chuck body and collet. For example, in certain implementations, a portion of the central bore 806 can have an out-of-round cross-sectional shape and the outer surface of the collet can have an out-of-round shape at least approximately matching the out-of-round cross-sectional shape of the central bore. When the collet is inserted into the central bore 806 , the out-of-round portion of the collet can be positioned within and matingly engage the out-of-round portion of the central bore 806 . Because the portions of the central bore 806 and collet are out-of-round, engagement between them at least restricts rotation of the collet relative to the chuck body 104 . In specific implementations, the out-of-round shape can be any of various shapes, such as hexagonal, triangular, rectangular, and ovular.
Also shown is FIG. 8 is a set screw depression 804 formed in an outer surface of the chuck body 104 . The depression 804 is configured to engage the set screw 108 thereby holding the chuck body 104 firmly in place within the chuck seat 404 (see FIG. 6 ).
FIGS. 9A-9C are detailed perspective views of a plurality of collets 102 A- 102 C. Collets 102 B, 102 C include longitudinal slits 902 cut in the compressible distal end 312 thereby forming jaws 904 . The jaws 904 are able to flex inward under the compression force from the chuck body 104 , thereby enabling a tight grip on the proximal end 306 of the fastener 202 . The slits 902 are narrow enough not to compromise the snug conformity or tight fit between the collets 102 B, 102 C and the proximal end 306 of the fastener 202 .
As shown in FIG. 9C , the jaw 904 of collet 102 C may have a cutting edge 906 configured to remove material from around the proximal end 306 of the fastener 202 . For example, the material may be bone which has grown around the edges of the proximal end 306 and must be cut away in order to expose enough of the fastener 202 to achieve a tight grip necessary for extracting the fastener. The collet 102 C can be rotated while applying a force to the collet directed toward the material to be removed. As the collet 102 C is rotated, the cutting edge 906 cuts through the material.
FIGS. 10A and 10B show a detailed side cutaway view and front view, respectively, of a collet 1002 . The collet 1002 is a radial engagement (RE) type collet with longitudinal slits 902 and short clearance cutters each having a cutting edge 906 . FIGS. 11A and 11B show a detailed side cutaway view and front view, respectively, of a collet 1006 . The collet 1006 is an RE type collet with a clearance cutting body 1008 , a cutting edge 906 , and longitudinal slits 902 . FIGS. 12A and 12B show a detailed side cutaway view and front view, respectively, of a collet 1010 . The collet 1010 is an RE type collet with a tor engage screw shank boring body 1012 , a cutting edge 906 , and longitudinal slits 902 . FIGS. 13A and 13B show a side view and front view, respectively, of a collet 1014 . The collet 1014 is a hex drive solid collet without a compressible distal end. FIGS. 14A and 14B show a side view and front view, respectively, of a collet 1018 . The collet 1018 is an “easy-out” type extractor solid collet without a compressible distal end. The distal ends of the collets 1014 , 1018 are not compressible, but include recesses for receiving a standard sized fastener head.
Solid collets, such as collets 1014 , 1018 are usable to insert a fastener having a standard head into bone tissue and to extract the fastener if the head has not broken away from the shank. As discussed above, if the head has indeed broken away from the shank or extracting the fastener by gripping the shank is more desirable, a collet having a compressible distal end may be more desirable.
FIGS. 15A and 15B show a detailed side cutaway view and front view, respectively, of a collet 1022 . The collet 1022 is an expandable tip collet for gripping hollow fasteners and non-fasteners from the inside of the fasteners and non-fasteners, respectively. For example, the tip of the collet 1022 can be inserted into the hollow interior of an embedded fastener. As the threaded proximal end of the collet 1022 is rotated and moved proximally via the hand tool 100 as discussed above, an interior member secured to the threaded proximal end correspondingly rotates and moves relative to an exterior member, which is prevented from proximal movement via the chuck body 104 . The distal tip of the interior member is beveled such that as it moves proximally relative to the exterior member, it causes the exterior member to expand outwardly until it tightly grips an interior surface of the hollow fastener. The embedded fastener can then be removed by pulling or rotating the hand tool 100 .
Like the hand tool 100 , the collets described herein can each have a central bore running the length of the collets to allow for passage of a guide wire as used in conjunction with a cannulated fastener (see, e.g., collets 1002 - 1022 of FIGS. 10A-15B ). In this manner, a guide wire can extend through the bore 408 in the hand tool 100 , the collet, and the fastener.
The components of the instruments 100 can be made from any of various materials. For example, in some embodiments, each of the components is made from a metal or metal alloy, such as steel, stainless steel, and/or aluminum. Also, one or more components can be made from a high-strength plastic or polymer.
FIG. 16 is a flow diagram illustrating one embodiment of a method 1600 for employing a fastener extraction and insertion instrument, such as instrument 100 , in accordance with the present invention. The method 1600 starts 1602 by accessing 1604 material requiring positional fixation or in which a fastener is positionally fixed. The method 1600 proceeds by providing 1606 an instrument (e.g., instrument 100 ) and installing 1608 a collet (e.g., collet 102 ) in the instrument. A proximal end of a fastener (e.g., proximal end 306 of fastener 202 ) is then fitted 1610 into a snugly conforming compressible distal end (e.g., end 312 ) of the collet. The proximal end of the fastener is partially tightened 1612 within the collet by adjusting a tightening portion of a closing mechanism, e.g., turning a knob (e.g., knob 110 ) in a tightening direction. Adjusting the tightening portion urges the distal end of the collet against a chuck body of the instrument and partially compresses the distal end of the collet against the fastener. The proximal end of the fastener is fully tightened and locked 1614 in place by adjusting a locking portion, e.g., depressing a lever (e.g., lever 112 ). Adjusting the locking portion further urges the distal end of the collet against the chuck body and further compresses the distal end of the collet against the fastener.
If the fastener is already embedded in the material, then it is extracted 1618 by operating a handle (e.g., 106 ) of the instrument, such as pulling the handle away from the material. If the fastener 202 is not embedded or only partially embedded in the material, then the fastener is inserted 1620 inserted into the material to completely embed the fastener in the material by operating the handle, such as pushing the handle toward the material. When the extraction 1618 or insertion 1620 of the fastener is complete, then the fastener is at least partially loosened or unlocked 1622 from the instrument by lifting the lever and, if necessary, further loosened by loosening 1624 the collet by turning the knob in a loosening direction opposite the tightening direction. Unlocking 1622 the fastener and further loosening 1624 the collet allows the fastener to be separated 1626 from the collet. The collet is then removed 1628 from the instrument. If the collet can be reused as determined at 1630 , then the method ends 1634 . However, if the collet cannot be reused, such as due to contamination, as determined at 1630 , then the collet may be discarded 1632 prior to the end 1634 of the method 1600 .
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | An apparatus, system, and method are disclosed for positional fixation of a fastener, including but not limited to the extraction of an orthopedic screw. According to one embodiment, an instrument is provided which accepts a collet designed to conform to a proximal end of a variety of types and sizes of fasteners. The collet is installed through a chuck body, which is seated in a distal end of a handle. A closing mechanism within the handle causes the collet to tightly grip and lock onto the proximal end of the fastener. A compressible distal end of the collet may have longitudinal slits that define jaws for improving gripping flexibility. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to apparatus for dyeing or otherwise treating textile materials.
More specifically, the invention is directed to dyeing apparatus employing a perforated cylindrical beam for winding thereon materials to be treated and further including means dewatering or demoisturing the treated materials.
2. Prior Art
There are known a number of dyeing apparatus designed for forcing treatment liquids such as dyeing, bleaching and other media into and through textile materials such as yarns, tapes and other fabrics that are wound on a perforated cylinder commonly known as "beam". The treatment liquid is forced under pressure to penetrate the layers of material radially from inside of the beam on which the material is wound or wrapped. Difficulty has been experienced with many of the prior art apparatus in securing uniformity of treatment in all portions of the material often resulting in different shades or hues both radially and axially of the roll of material.
To eliminate such treatment defects, it has been proposed as disclosed for example in U.S. Pat. No. 3,685,324 to rotate the beam during treatment of the material thereon. Such devices are however disadvantageous in that complicated mechanical arrangements and high power consumption are required.
SUMMARY OF THE INVENTION
It is therefore the primary object of the present invention to provide an improved beam-dyeing apparatus which incorporates structural features tailored to attain uniformity and repidness of treatment of textile materials.
A more specific object of the invention is the provision of means in a beam-dyeing apparatus of maintaining uniform distribution and penetration of treatment liquids in both the radial and the axial direction of the beam on which the material to be treated is wound.
According to the invention, there is provided a dyeing apparatus which comprises a cylindrical vessel of generally circular cross-section extending longitudinally along a generally horizontal axis and having a removable dished end; a perforated hollow beam supported within said vessel and extending longitudinally along said horizontal axis and adapted to wind upon its exterior a material to be treated; anular rim members secured to and extended transversely around said beam at opposite ends thereof and defining therebetween an annular volumetric section for retaining the material; a perforated flow-rectifying panel extending longitudinally of the vessel and overlying the upper portion of said beam; means supplying and circulating treatment liquid through the vessel; a first liquid flow take-out means mounted on the exterior of the vessel adjacent the front end thereof and passing liquid from the upper portion of the vessel to said supplying and circulating means; a second liquid flow take-out means positioned substantially centrally of the vessel and passing liquid from the bottom portion of the vessel to said circulating means; and means controlling the amount of liquid take-out from the vessel through said first and second take-out means.
Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which preferred structural embodiments incorporating the principles of the present invention are shown by way of example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross-sectional, partly schematic, view of a beam-dyeing apparatus provided in accordance with the invention;
FIG. 2 is a longitudinal cross-sectional, partly schematic, view of another beam-dyeing apparatus according to the invention which is capable of performing the dyeing operation at once and subsequent dewatering or demoisturing operation;
FIG. 3 is a transverse cross-sectional view taken on the line III--III of FIG. 2; and
FIG. 4 is a transverse cross-sectional view taken on the line IV--IV of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and FIG. 1 in particular, there is shown a dyeing apparatus 10 having a cylindrical vessel 11 of generally circular transverse cross-section and extending longitudinally along the generally horizontal axis. The vessel 11 has dished ends, one of which designated at 12 is removable for purposes hereafter noted. A perforated hollow beam 13 is supported within the vessel 11 and extending along the horizontal axis thereof. The beam 13 is capable to support material F to be dyed, which material is wound upon the exterior of the beam 12 in the manner of a bobbin. The beam 13 has a multiplicity of perforations 13' formed in and distributed uniformly around the periphery of the beam 13 to allow dye liquid to flow into and through the material F.
The beam 13 has a pair of rollers 14,14' at its opposite ends which are movably mounted on a rail 15 secured to and extending longitudinally of the vessel 11.
A pair of annular rim members or spacers 16,16' are secured to and extended transversely around the beam 13 at opposite ends thereof. The rim members 16,16' define therebetween an annular volumetric section in which the material or fabric F wound on the beam 13 is confined and retained in place.
A lid or cover 17 is provided which is centrally engageable with a rod 18 connected to a handle 19. Rotating this handle in one direction clamps the lid 17 to seal the front end of the beam 13 and in the opposite direction releases the lid 17 to permit removal of the beam 13 when a cycle of dyeing operation has been completed.
A cap 20, which forms the front dished end 12 of the vessel, is threadedly engaged with the handle rod 18 and removably connected to the vessel 11 by suitable means such as a clamping ring 21.
A perforated, flow-rectifying panel 22 is provided within the vessel 11 in a position overlying the upper portion of the beam 13. The panel 22 which extends longitudinally of the vessel 11 has a perforated center portion 22' disposed in coextensive relation with the perforated wall of the beam 13, with one end of the panel 22 secured to the inner wall of the vessel 11 and the other end to the terminal end of a flared conduit connector 23. The other or rear end of the beam 13 is removably fitted circumferentially to the flared portion of the conduit connector 23.
There is provided a first liquid flow take-out means which is in the form of an annular jacket 24 mounted on the exterior of the vessel 11 adjacent the front end of the vessel 11. The jacket 24 has a bottom portion 24' coextensive with and opening into a liquid flow conduit 25.
The upper portion 11a of the vessel 11 which registers with the jacket 24 is perforated to establish liquid communication between the beam 13, the jacket 24 and the flow conduit 25.
A second liquid flow take-out means in the form of a pipe 26 is connected to the bottom of the vessel 11 and ties into the flow conduit 25 and located substantially centrally of the vessel 11. The bottom portion 11b of the vessel which registers with the flow take-out pipe 26 is also perforated so as to establish liquid communication between the beam 13, the pipe 26 and the conduit 25.
The conduit 25 for withdrawing dye liquid from the vessel 11 is connected via valve 27 to a heat exchanger 28 whereby dye or treatment liquid is maintained at a predetermined temperature. A pump 29, preferably of a reversible function, driven by a motor 30 is connected at its suction side to the heat exchanger 28 and at its discharge side to the flared connector 23 via conduit 31.
In the operation of the apparatus thus constructed, dye liquid is supplied from a source not shown through valve 33 and distributed by pump 29 through conduit 31 and through the flared connector 23 whereupon the liquid is introduced into the interior of the beam 13. The liquid is then forced radially outward through the perforated beam 13 and into the layers of fabric F wound thereon, and after soaking fabric F to depth, is withdrawn out of the vessel 11. In such instance, a portion of the liquid is passed upwardly through the flow-rectifying panel 22 and through the upper perforated wall 11a into the first flow take-out means, namely, jacket 24, thence into conduit 25. The remaining portion of the liquid is passed downwardly through the bottom perforated wall 11b and through the second flow take-out means, namely pipe 26 into common conduit 25. Designated at 34 is an outlet valve for draining used treatment liquid.
It has now been found that uniform and efficient treatment of the material F can be achieved by regulating the flow rate of liquid through the second flow take-out means 26 to be preferably in the range of one-third (1/3) to four-fifth (4/5) of the flow through the first flow take-out means 24. As a practical expediency, there is provided in the liquid passage of the flow take-out pipe 26 a control valve 32 whereby the rate of withdrawal of liquid from the vessel can be controlled in the above preferred range.
Referring now to FIGS. 2-4, inclusive, there is shown another form of apparatus according to the invention which is basically the same as the apparatus shown in FIG. 1 in so far as concerns the principles of the invention. Hence, all parts of the apparatus which are common and identical are indicated by the same reference numerals, and the following description will deal with only those apparatus parts which are added.
Designated at 35 is an elongated non-perforated dummy cylinder adapted primarily to reduce the volume within the vessel 11 which must be supplied with treatment liquid. The dummy cylinder 35 is positioned within the hollow portion of the beam 13 to define therewith an annular flow passage for the dye liquid. For dewatering or demoisturing the material F which has been treated, there is provided means generally designated 36 which stores and supplies compressed air to the interior of the vessel 11. The means 36 comprises an air tank 37 installed outside of the vessel 11 for storing compressed air supplied from a suitable source (not shown) via valve 38. To the tank 37 are connected a first piping 39 leading to and communication with the interior of the dummy cylinder 35, a second piping 40 leading to and communicating with the space S 1 at the rear end of the vessel 11 and a third piping 41 leading to and communicating with the space S 2 at the front end of the vessel 11, the arrangement being that a closed circuit is formed for normally maintaining an equalized air pressure therethrough.
A fourth piping 42 is connected at one end to the bottom of the tank 37 and opens at the other end into the vessel 11 at a position overlying the perforated panel 22 for supplying compressed air into the vessel 11 during dewatering of the treated material F.
It will be noted that the above air-store-and supply means 36 serves to establish pressure equalizing communication between a given interior region of the vessel and the hollow portion of the dummy cylinder 35 thereby reducing the structural loading upon the apparatus 10 as a whole.
Designated at 43 is a treatment liquid supply valve and at 44 is a drainage valve. The operation of dewatering or demoisturing treated fabric F is disclosed in the copending U.S. application Ser. No. 957,181 and will require no further description as this part of the disclosure does not constitute positive features of the invention. Designated at 45 are steam traps.
It will be noted that the liquid flow take-out means 24 and 26 provided commonly in the two forms of apparatus above described are located at the respective specified positions and the flow of liquid therethrough is controlled to be in the range of 1/3 to 4/5 such that uniform and sufficient treatment of the material F can be achieved.
If necessary, the operation of the pump 29 may be reversed so that the direction of flow of treatment liquid is changed.
Although various minor modifications may be suggested by those versed in the art, it should be understood that we wish to embody within the scope of the patent warranted hereon, all such embodiments as reasonably and properly come within the scope of our contribution to the art. | A dyeing apparatus is disclosed which has a cylindrical vessel and a perforated hollow beam supported therein. Textile materials such as yarns, tapes and the like are wound upon the exterior of the beam and soaked to depth with treatment liquid forced radially through the perforations of the beam into the layers of wound-up material. Liquid is withdrawn from the vessel for re-circulation through a first take-out means provided adjacent the upper portion of the vessel and through a second take-out means provided centrally of the bottom portion of the vessel. Control means is provided to regulate the flow of liquid through the two take-out means to be in a specified ratio. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. patent application Ser. No. 11/468,565, filed Aug. 30, 2006, which is a continuation of U.S. patent application Ser. No. 11/468,511, entitled “System and Method for Reducing Thrust Acting On Submersible Pumping Components”, filed Aug. 30, 2006, and is hereby incorporated by reference in its entirety.
BACKGROUND
When pumping downhole fluids with an electric submersible pump, a variety of hydraulic forces act on various components. For example, impellers in centrifugal, submersible pumps tend to create large reaction forces that act in a direction opposite to the direction of fluid flow. The large reaction forces are resisted by, for example, a thrust washer in each stage of a floater style pump or by a motor protector thrust bearing in a compression style pump.
The thrust created by the impeller in each stage of a submersible pump can be problematic in a variety of submersible pump types, including pumps with mixed flow stages and pumps with radial flow stages. In some floater style designs, for example, a significant portion of power loss in the pump is due to thrust friction occurring at the outer thrust washer due to relatively high friction induced torque at this radially outlying position. If the outer thrust washer is removed from the floater style stage, however, the lack of any seal functionality increases leakage loss.
SUMMARY
In general, the present invention provides a technique for pumping fluids in a submerged environment. The technique is useful with submersible pumping systems, such as those used in wellbore applications for pumping downhole fluids. A submersible pumping system is designed to utilize thrust control features with the submersible pump to reduce certain thrust loads otherwise acting on submersible pump components.
BRIEF DESCRIPTION OF THE DRAWINGS
Certain embodiments of the invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1 is an elevation view of an embodiment of an electric submersible pumping system deployed in a wellbore, according to an embodiment of the present invention;
FIG. 2 is a partial cross-sectional view of an embodiment of the submersible pump illustrated in FIG. 1 , according to an embodiment of the present invention;
FIG. 3 is a partial cross-sectional view of another embodiment of the submersible pump illustrated in FIG. 1 , according to an embodiment of the present invention;
FIG. 4 is a partial cross-sectional view of another embodiment of the submersible pump illustrated in FIG. 1 , according to an embodiment of the present invention;
FIG. 5 is a partial cross-sectional view of another embodiment of the submersible pump illustrated in FIG. 1 , according to an embodiment of the present invention; and
FIG. 6 is a partial cross-sectional view of another embodiment of the submersible pump illustrated in FIG. 1 , according to an embodiment of the present invention.
DETAILED DESCRIPTION
In the following description, numerous details are set forth to provide an understanding of the present invention. However, it will be understood by those of ordinary skill in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
The present invention relates to a system and methodology for reducing certain effects of thrust loads created while pumping fluids. For example, the system and methodology can be used in submersible pumping systems having centrifugal style, submersible pumps. One or more features are incorporated into the submersible pumping system to manage the hydraulic forces acting on external surfaces of the pump impellers that tend to create large reaction forces acting opposite to the flow direction of the pumped fluid.
Referring generally to FIG. 1 , an embodiment of a submersible pumping system 20 , such as an electric submersible pumping system, is illustrated. Submersible pumping system 20 may comprise a variety of components depending on the particular application or environment in which it is used. Examples of components utilized in pumping system 20 comprise at least one submersible pump 22 , at least one submersible motor 24 , and one or more motor protectors 26 that are coupled together to form the submersible pumping system.
In the example illustrated, submersible pumping system 20 is designed for deployment in a well 28 within a geological formation 30 containing desirable production fluids, such as petroleum. A wellbore 32 is drilled into formation 30 , and, in at least some applications, is lined with a wellbore casing 34 . Perforations 36 are formed through wellbore casing 34 to enable flow of fluids between the surrounding formation 30 and the wellbore 32 .
Submersible pumping system 20 is deployed in wellbore 32 by a deployment system 38 that may have a variety of configurations. For example, deployment system 38 may comprise tubing 40 , such as coiled tubing or production tubing, connected to submersible pump 22 by a connector 42 . Power is provided to the at least one submersible motor 24 via a power cable 44 . The submersible motor 24 , in turn, powers submersible pump 22 which can be used to draw in production fluid through a pump intake 46 . Within submersible pump 22 , a plurality of impellers is rotated to pump or produce the production fluid through, for example, tubing 40 to a desired collection location which may be at a surface 48 of the Earth.
It should be noted the illustrated submersible pumping system 20 is only one example of many types of submersible pumping systems that can benefit from the features described herein. For example, other components can be added to the pumping system, and other deployment systems may be used. Additionally, the production fluids may be pumped to the collection location through tubing 40 or through the annulus around deployment system 38 . The submersible pump or pumps 22 also can utilize different types of stages, such as mixed flow stages or radial flow stages.
Referring generally to FIG. 2 , a cross-sectional view is provided of a portion of one embodiment of submersible pump 22 . In this embodiment, submersible pump 22 comprises a plurality of stages 50 . Each stage 50 comprises an impeller 52 coupled to a shaft 54 rotatable about a central axis 56 . Rotation of shaft 54 by submersible motor 24 causes impellers 52 to rotate within an outer pump housing 58 . Each impeller 52 draws fluid in through an impeller or stage intake 60 and routes the fluid along an interior impeller passageway 62 before discharging the fluid through an impeller outlet 64 and into an axially adjacent diffuser 66 . The interior passageway 62 is defined by the shape of an impeller housing 68 , and housing 68 may be formed to create an impeller for a floater stage, as illustrated in FIG. 2 , or for a compression stage (see FIG. 6 ). Additionally, impeller housing 68 may be designed to create a mixed flow stage, a radial flow stage, or another suitable stage style for use in submersible pump 22 .
In the embodiment illustrated in FIG. 2 , an inner thrust member 70 , such as an inner thrust washer, is positioned to resist thrust loads, e.g. downthrust loads, created by the rotating impeller 52 . In this embodiment, inner thrust washer 70 is positioned in an impeller feature 72 , such as a recess formed in an upper portion of impeller housing 68 . The inner thrust washer 70 is disposed between the impeller 52 and a radially inward portion 74 of the next adjacent upstream diffuser 66 . Instead of a conventional outer thrust washer, however, an axially compliant outer seal member 76 is used. In the embodiment of FIG. 2 , seal member 76 comprises a radial seal 78 positioned in sealing engagement with a generally axially oriented section 80 of impeller housing 68 . Thus, the seal member 76 forms a sealing point with section 80 of impeller 52 , and the sealing point is translatable axially along section 80 . The radial seal 78 may be positioned within a recess 82 formed in a portion of the adjacent diffuser 66 , as illustrated. Accordingly, an outer seal is formed between the impeller and the adjacent diffuser without the creation of unwanted reaction forces on radially outward surfaces within submersible pump 22 .
An alternate embodiment of seal member 76 is illustrated in FIG. 3 . In this embodiment, inner thrust member 70 is similarly positioned at a radially inward position. However, seal member 76 comprises a radially outlying member 84 , such as an outer washer, supported by an axially compliant member 86 . The axially compliant member 86 enables translation of seal member 76 in a generally axial direction by virtue of the compression and expansion of member 86 . By way of example, axially compliant member 86 may comprise a spring member or other type of compliant member made from a variety of materials, including metallic materials, elastomeric materials and composite materials. It should be noted the embodiment illustrated in FIGS. 2 and 3 also can be used with compression stages to eliminate front seal leakage.
In another embodiment of the system for managing thrust loads, the net thrust load, e.g. net downthrust load, can be reduced by pressure balancing a thrust washer area so the impeller discharge pressure rather than the impeller inlet pressure acts on the thrust washer. In this embodiment, a flow passage is formed across a thrust member 88 to pressure balance the thrust member 88 . The flow passage can be routed, for example, between the thrust member 88 and the impeller 52 or between the thrust member 88 and a thrust pad of the adjacent diffuser. In one example, the thrust member 88 , e.g. a thrust washer, is held in a retaining feature 90 of impeller 52 at a position located radially outward of an eye 91 of the impeller, as illustrated in FIG. 4 . The retaining feature 90 may comprise a groove 92 formed in a lower portion of the impeller 52 . A flow passage 94 is routed along a backside of thrust member 88 between thrust member 88 and impeller 52 , as illustrated by arrow 96 in FIG. 4 . The flow path or passage 94 creates a flow of fluid during operation of submersible pump 22 which decreases the thrust load acting on the thrust member 88 . Alternatively, flow passage 94 can be formed between thrust member 88 and the adjacent diffuser 66 (see dashed lines in FIG. 4 ). For example, flow can be directed along radial grooves formed across the thrust member 88 and/or the adjacent diffuser 66 to decrease the thrust load acting on thrust member 88 .
The flow passage 94 may be created by a variety of techniques, including spot facing impeller 52 at several locations in the retaining feature region to create the passage behind thrust member 88 . The thrust member 88 may be press fit into retaining feature 90 to secure the thrust member at a location that forms the desired flow passage 94 . In this embodiment, the net thrust reducing flow is directed from a radially outward region of thrust member 88 , along the backside of thrust member 88 , and out along a radially inward region of thrust member 88 . In some embodiments, the flow of fluid through flow passage 94 is expelled out through a gap between a washer bore and an outside diameter of an impeller front seal. It should be noted that the flow resistance of the balance flow passage 94 should be less than the flow resistance of the front seal gap in each stage.
Another embodiment of the system and methodology for pumping fluids and managing thrust loads is illustrated in FIG. 5 . In this embodiment, the net downthrust load acting on a downthrust member 98 is reduced. Downthrust member 98 may comprise a downthrust pad or thrust washer and may be located at a radially inward position, as illustrated. The downthrust acting on member 98 is reduced by incorporating an upper thrust member 100 , such as an upper thrust pad or washer. Additionally, one or more balance holes 102 are positioned to allow leakage of fluid from interior passage 62 of impeller 52 and across upper thrust member 100 . In the embodiment illustrated, balance holes 102 are formed through an upper portion of impeller housing 68 above the interior passage 62 , and they are oriented in a generally axial direction. However, the positioning and orientation of balance holes 102 can be adjusted as desired for specific applications.
At start up of submersible pump 22 , the impeller 52 of each stage 50 rests on its downthrust member 98 . After startup, impellers 52 rotate and a leakage flow is induced by the discharge of each impeller 52 across upper the thrust member 100 and through balance hole(s) 102 . This leakage flow reduces the pressure in the cavity between thrust members 98 and 100 , causing the impeller 52 to shift upwardly and to contact the upper thrust member 100 . The face seal formed by the upper thrust member 100 also seals off leakage flow through the balance holes 102 . Accordingly, this configuration provides an improved axial balance because the top area of impeller 52 that is located radially inward of upper thrust member 100 is exposed to impeller inlet pressure rather than impeller discharge pressure. Also, the embodiment illustrated in FIG. 5 may utilize seal member 76 to facilitate sealed, axial movement of impeller 52 . For example, seal member 76 may comprise radial seal 78 which allows axial translation of the impeller while maintaining a seal between the impeller and an adjacent diffuser. The embodiment illustrated in FIG. 5 is particularly applicable to radial flow stages and enables the stages to have a compact stage height relative to conventional designs.
Referring generally to FIG. 6 , another embodiment of the system and methodology for pumping fluids and managing thrust loads is illustrated. In this embodiment, submersible pump 22 of submersible pumping system 20 is formed with a plurality of stacked, compression stages 104 having impellers 52 rotated by shaft 54 . With compression stages 104 , the net thrust load, e.g. downthrust load, resulting from rotation of impellers 52 is resisted by a protector bearing 106 (illustrated schematically in dashed lines) located in motor protector 26 . The thrust load on protector bearing 106 is reduced by effectively porting pressure from an inlet 108 of a lower or upstream stage 104 to a balance chamber 110 of an upper or downstream stage 104 . In some embodiments, the upper/downstream stage 104 is the topmost stage, and the lower/upstream stage 104 is a lower or lowermost stage 104 in submersible pump 22 . In other embodiments, the system can be designed such that the inlet 108 is the inlet of the submersible pump.
The pressure may be ported by creating a pressure relief path or fluid passageway 112 from the selected stage inlet 108 to the selected balance chamber 110 . In one embodiment, passageway 112 is routed at least partially through shaft 54 , and the passageway may be routed generally along a central axis of shaft 54 . Additionally, an orifice 114 or other restrictor may be located in the passageway 112 to control the leakage flow rate from the upper/downstream stage 104 to the lower/upstream stage 104 .
Specific components used in submersible pumping system 20 can vary depending on the actual well application in which the system is used. The specific components, component size and component location for managing net thrust loads also can vary from one submersible pumping system to another and from one well application to another. The specific embodiment utilized for controlling the thrust loads acting on certain components within the submersible pumping system is selected based on a variety of factors, e.g. the number and arrangement of submersible pumps, submersible motors, and motor protectors as well as the specific well environment, well application and production requirements. Other components can be attached to, or formed as part of, the electric submersible pumping system.
Accordingly, although only a few embodiments of the present invention have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this invention. Such modifications are intended to be included within the scope of this invention as defined in the claims. | A technique is provided to facilitate pumping of fluids in a well environment. A submersible pumping system having a submersible pump incorporates features that manage thrust loads resulting from rotating impellers. The thrust reducing features cooperate with the action of the impellers in one or more pump stages to reduce forces otherwise acting on certain pump related components. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/030,262, filed on Feb. 21, 2008, which is hereby incorporated in its entirety herein by reference.
FIELD
[0002] The invention relates generally to a multiple speed transmission having a plurality of planetary gear sets and a plurality of torque transmitting devices and more particularly to a transmission configured for a front wheel drive vehicle having eight or more speeds, four planetary gear sets and a plurality of torque transmitting devices.
BACKGROUND
[0003] The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
[0004] A typical multiple speed transmission uses a combination of a plurality of torque transmitting mechanisms, planetary gear arrangements and fixed interconnections to achieve a plurality of gear ratios. The number and physical arrangement of the planetary gear sets, generally, are dictated by packaging, cost and desired speed ratios.
[0005] While current transmissions achieve their intended purpose, the need for new and improved transmission configurations which exhibit improved performance, especially from the standpoints of efficiency, responsiveness and smoothness and improved packaging, primarily reduced size and weight, is essentially constant. Accordingly, there is a need for an improved, cost-effective, compact multiple speed transmission.
SUMMARY
[0006] In one aspect of the present invention, a transaxle is provided having a transmission input member, a transmission output member, a plurality of planetary gear sets, and a plurality of torque-transmitting mechanisms.
[0007] In another aspect of the present invention, a housing having a first wall, a second wall and a third wall extending between the first and second walls is provided. The first, second, third and fourth planetary gear sets are disposed within the housing. The first planetary gear set is adjacent the first wall, the third planetary gear set is adjacent second wall, the second planetary gear set is adjacent the first planetary gear set and the fourth planetary gear set is between the second and third planetary gear sets.
[0008] In yet another aspect of the present invention, each planetary gear set has a sun gear member, a ring gear member, and a planet carrier member supporting a plurality of planet gears each configured to intermesh with both the sun gear member and the ring gear member. The ring gear member of the first planetary gear set is permanently coupled to the sun gear member of the second planetary gear set, the sun gear member of the first planetary gear set is permanently coupled to the sun gear member of the fourth planetary gear set, the ring gear member of the third planetary gear set is permanently coupled to the planet carrier member of the fourth planetary gear set.
[0009] In yet another aspect of the present invention, the output member is permanently coupled with the carrier members of the second and third planetary gear sets. The input member is permanently coupled with the carrier member of the first planetary gear set.
[0010] In yet another aspect of the present invention, the housing has a first area defined radially inward from an outer periphery of the planetary gear sets and axially bounded by the first wall and the first planetary gear set. A second area is defined radially inward from the outer periphery of the planetary gear sets and axially bounded by the first and second planetary gear sets. A third area is defined radially inward from the outer periphery of the planetary gear sets and axially bounded by the second and fourth planetary gear sets. A fourth area is defined radially inward from the outer periphery of the planetary gear sets and axially bounded by the third and fourth planetary gear set. A fifth area is defined radially inward from the outer periphery of the planetary gear sets and axially bounded by the third planetary gear set and the second wall. A sixth area is defined radially inward from the third wall and radially outward from the outer periphery of the planetary gear sets and axially bounded by the first wall and the second wall.
[0011] In yet another aspect of the present invention, the first clutch is disposed in at least one of the first, second, third and sixth areas and is selectively engageable to interconnect the ring gear member of the first planetary gear set with the sun gear member of the third planetary gear set.
[0012] In yet another aspect of the present invention, a second clutch is disposed in at least one of the first, second, third and sixth areas and is selectively engageable to interconnect the planet carrier member of the first planetary gear set with the sun gear member of the third planetary gear set.
[0013] In yet another aspect of the present invention, a third clutch is disposed in at least one of the first, second, third, fourth, fifth and sixth areas and is selectively engageable to interconnect the ring gear member of the second planetary gear set with the sun gear member of the third planetary gear set.
[0014] In yet another aspect of the present invention, a first brake is disposed in at least one of the first, third, fifth and sixth areas and is selectively engageable to interconnect the sun gear member of the first planetary gear set and the sun gear member of the fourth planetary gear set to the housing.
[0015] In yet another aspect of the present invention, a second brake is disposed in at least one of the first, fourth, fifth and sixth areas and is selectively engageable to interconnect the ring gear member of the fourth planetary gear set to the housing.
[0016] In still another aspect of the present invention, the clutches and the brakes are selectively engageable to establish at least eight forward speed ratios and at least one reverse speed ratio between the transmission input member and the transmission output member.
[0017] In still another aspect of the present invention, a power transfer assembly has a first and a second transfer gear and a power transfer member. The first transfer gear is rotatably fixed to the engine output member and the second transfer gear is rotatably fixed to the transmission input member. The power transfer member is rotatably coupled to the first and second transfer gears for transferring rotational energy from the first transfer gear to the second transfer gear.
[0018] In still another aspect of the present invention, a final drive planetary gear set has a final drive sun gear coupled to the transmission output member, a final drive ring gear coupled to the transmission housing and a final drive carrier member rotatably supporting a final drive plurality of pinion gears intermeshed with both the final drive sun gear and the final drive ring gear.
[0019] In still another aspect of the present invention, a differential gear set having a differential housing coupled to the final drive carrier member and has a pair of gears rotatably supported in the differential housing. One of the pair of the gears is rotatably fixed to one of a pair of road wheels and the other of the pair of the gears is rotatably fixed to the other one of the pair of road wheels.
[0020] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
[0021] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
[0022] FIG. 1A is a schematic diagram of a gear arrangement for a front wheel drive transmission, according to the principles of the present invention;
[0023] FIG. 1B is a chart showing the locations of the torque transmitting devices for the arrangement of planetary gear sets of the transmission shown in FIG. 1A , in accordance with the embodiments of the present invention; and
[0024] FIG. 2 is a schematic diagram of a front wheel drive transaxle arrangement incorporating the gear arrangement of the transmission of FIG. 1A and FIG. 1B , according to the principles of the present invention.
DETAILED DESCRIPTION
[0025] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
[0026] Referring now to FIG. 1A , an embodiment of a front wheel drive multi-speed or eight speed transmission is generally indicated by reference number 10 . The transmission 10 is illustrated as a front wheel drive or transverse transmission, though various other types of transmission configurations may be employed. The transmission 10 includes a transmission housing 12 , an input shaft or member 14 , an output shaft or member 16 and a gear arrangement 18 . The input member 14 is continuously connected to an engine (shown in FIG. 2 ) or to a turbine of a torque converter (not shown). The output member 16 is continuously connected with a final drive unit (not shown) or transfer case (shown in FIG. 2 ).
[0027] The gear arrangement 18 of transmission 10 includes a first planetary gear set 20 , a second planetary gear set 22 , a third planetary gear set 24 , and a fourth planetary gear set 26 . The planetary gear sets 20 , 22 , 24 and 26 are connected between the input member 14 and the output member 16 .
[0028] In a preferred embodiment of the present invention, the planetary gear set 20 includes a ring gear member 20 A, a planet carrier member 20 B that rotatably supports a set of planet or pinion gears 20 D (only one of which is shown) and a sun gear member 20 C. The ring gear member 20 A is connected for common rotation with a first shaft or intermediate member 42 . The planet carrier member 20 B is connected for common rotation with input shaft or member 14 and second shaft or intermediate member 44 . The sun gear member 20 C is connected for common rotation with a third shaft or intermediate member 46 . The pinion gears 20 D are each configured to intermesh with both the sun gear member 20 C and the ring gear member 20 A.
[0029] The planetary gear set 22 includes a ring gear member 22 A, a planet carrier member 22 B that rotatably supports a set of planet or pinion gears 22 D and a sun gear member 22 C. The ring gear member 22 A is connected for common rotation with a fourth shaft or intermediate member 48 . The planet carrier member 22 B is connected for common rotation with output shaft or member 16 . The sun gear member 22 C is connected for common rotation with the first shaft or intermediate member 42 . The pinion gears 22 D are each configured to intermesh with both the sun gear member 22 C and the ring gear member 22 A.
[0030] The planetary gear set 24 includes a ring gear member 24 A, a planet carrier member 24 B that rotatably supports a set of planet or pinion gears 24 D and a sun gear member 24 C. The ring gear member 24 A is connected for common rotation with a fifth shaft or intermediate member 50 . The planet carrier member 24 B is connected for common rotation with the output shaft or member 16 . The sun gear member 24 C is connected for common rotation with the sixth shaft or intermediate member 52 . The pinion gears 24 D are each configured to intermesh with both the sun gear member 24 C and the ring gear member 24 A.
[0031] The planetary gear set 26 includes a ring gear member 26 A, a carrier member 26 B that rotatably supports a set of planet or pinion gears 26 D and a sun gear member 26 C. The ring gear member 26 A is connected for common rotation with a seventh shaft or intermediate member 54 . The planet carrier member 26 B is connected for common rotation with the fifth shaft or intermediate member 50 . The sun gear member 26 C is connected for common rotation with the third shaft or intermediate member 46 . The pinion gears 26 D are each configured to intermesh with both the sun gear member 26 C and the ring gear member 26 A.
[0032] The transmission 10 also includes a plurality of torque-transmitting mechanisms or devices including a first clutch 66 , a second clutch 68 , a third clutch 70 , a first brake 72 and a second brake 74 . The first clutch 66 is selectively engagable to connect the first shaft or intermediate member 42 to the sixth shaft or intermediate member 52 . The second clutch 68 is selectively engagable to connect the second shaft or intermediate member 44 to the sixth shaft or intermediate member 52 . The third clutch 70 is selectively engagable to connect the fourth member or intermediate member 48 to the sixth shaft or intermediate member 52 . The first brake 72 is selectively engagable to connect the third shaft or intermediate member 46 to the transmission housing 12 to restrict rotation of the member 46 relative to the transmission housing 12 . Finally, the second brake 74 is selectively engagable to connect the seventh shaft or intermediate member 54 to the transmission housing 12 to restrict rotation of the member 54 relative to the transmission housing 12 .
[0033] The transmission 10 is capable of transmitting torque from the input shaft or member 14 to the output shaft or member 16 in at least eight forward torque ratios and one reverse torque ratio. Each of the forward torque ratios and the reverse torque ratio are attained by engagement of one or more of the torque-transmitting mechanisms (i.e. first clutch 66 , second clutch 68 , third clutch 70 , first brake 72 and second brake 74 ). Those skilled in the art will readily understand that a different speed ratio is associated with each torque ratio. Thus, eight forward speed ratios may be attained by the transmission 10 .
[0034] The transmission housing 12 includes a first wall or structural member 102 , a second wall or structural member 104 and a third wall or structural member 106 . The third wall 106 interconnects the first and second walls 102 and 104 to define a space or cavity 110 . Input shaft or member 14 is supported by the first wall 102 by bearings 112 . Output shaft or member 16 is supported by the second wall 104 by bearings 114 . The planetary gear sets 20 , 22 , 24 and 26 and the torque-transmitting mechanisms 66 , 68 , 70 , 72 and 74 are disposed within cavity 110 . Further, cavity 110 has a plurality of areas or zones A, B, C, D, E, and F in which the plurality of torque transmitting mechanisms 66 , 68 , 70 , 72 and 74 will be specifically positioned or mounted, in accordance with the preferred embodiments of the present invention.
[0035] As shown in FIG. 1A , zone A is defined by the area or space bounded by: the first wall 102 , planetary gear set 20 , radially inward by a reference line “L” which is a longitudinal line that is axially aligned with the input shaft 14 , and radially outward by a reference line “M” which is a longitudinal line that extends adjacent an outer diameter or outer periphery of the planetary gear sets 20 , 22 , 24 and 26 . While reference line “M” is illustrated as a straight line throughout the several views, it should be appreciated that reference line “M” follows the outer periphery of the planetary gear sets 20 , 22 , 24 and 26 , and accordingly may be stepped or non-linear depending on the location of the outer periphery of each of the planetary gear sets 20 , 22 , 24 and 26 . Zone B is defined by the area bounded by: planetary gear set 20 , the planetary gear set 22 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone C is defined by the area bounded by: the planetary gear set 22 , the planetary gear set 26 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone D is defined by the area bounded by: the planetary gear set 24 , the planetary gear set 26 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone E is defined by the area bounded by: the planetary gear set 24 , the second end wall 104 , radially outward by reference line “M”, and radially inward by reference line “L”. Zone F is defined by the area bounded by: the first wall 102 , the second wall 104 , radially inward by reference line “M” and radially outward by the third wall 106 .
[0036] In the gear arrangement 18 of transmission 10 shown in FIG. 1A , the planetary gear set 20 is disposed closest to the first wall 102 , the planetary gear set 24 is disposed closest to the second wall 104 , the planetary gear set 22 is disposed adjacent the planetary gear set 20 , and the planetary gear set 26 is disposed between the planetary gear sets 22 and 24 . The torque-transmitting mechanisms are intentionally located within specific Zones in order to provide advantages in overall transmission size, packaging efficiency, and reduced manufacturing complexity. In the particular example shown in FIG. 1A , the first and second clutches 66 and 68 are disposed within Zone A, the first and second brakes 72 and 74 are disposed within Zone F and the third clutch 70 is disposed within Zone C.
[0037] However, the present invention contemplates other embodiments where the torque-transmitting mechanisms 66 , 68 , 70 , 72 and 74 are disposed in the other Zones. The feasible locations of the torque-transmitting mechanisms 66 , 68 , 70 , 72 and 74 within the Zones are shown in the chart of FIG. 1B . The chart of FIG. 1B lists clutches and brakes in the left most column and the available zones to locate the clutch/brake in the top row. An “X” in the chart indicates that the present invention contemplates locating the clutch or brake in the zone listed in the top row. For example, first brake 72 may be located in zones A, C, E or F, second brake 74 may be located in zones A, D, E or F, first clutch 66 may be located in zones A, B, C or F, second clutch 68 may be located in zones A, B, C or F and third clutch 70 may be located in any of the zones A, B, C, D, E or F.
[0038] Referring now to FIG. 2 , a front wheel drive powertrain 150 incorporating a transaxle 154 is illustrated, in accordance with the embodiments of the present invention. Transaxle 154 includes the transmission 10 having the gear arrangement 18 of FIGS. 1A and 1B . Transaxle 154 is mounted to an engine 156 . Engine 156 produces a driving torque in an engine output shaft 157 that drives the input shaft 14 of transmission 10 , as described below. Engine 156 is generally an internal combustion engine, however, the present invention contemplates other types of engines such as electric and hybrid engines. Further, transaxle 154 includes a transfer chain or belt 158 , a drive sprocket or gear 160 , a driven sprocket or gear 162 , a differential 164 , a final drive planetary gear set 166 and a pair of drive axles 168 and 170 that drive a pair of road wheels 172 and 174 , respectively.
[0039] Transfer chain or belt 158 engages at a first end 180 a drive sprocket 160 and at a second end 182 the driven sprocket or gear 162 . The drive sprocket or gear 160 is coupled to engine output shaft or member 157 . Driven sprocket 162 is rotatably fixed to a drive shaft or rotatable member 159 . Drive shaft or rotatable member 159 is coupled to the input shaft 14 of transmission 10 . The output shaft 16 of transmission 10 is connected to an output sleeve shaft 163 . Output sleeve shaft 163 is coupled to a sun gear of a final drive planetary gear set 166 to achieve the desired gear ratio. A carrier member of final drive planetary gear set 166 supports a plurality of pinion gears which mesh with both the sun gear and a ring gear of final drive planetary gear set 166 . The carrier member of final drive planetary gear set 166 is rotatably coupled to and transfers driving torque to a housing of the differential 164 . Differential 164 transfers the driving torque generated by engine 156 to the two drive axles 168 and 170 through two sets of bevel gears rotationally supported in the differential housing. Drive axles 168 and 170 are rotatably fixed to and independently driven by the bevel gears of the differential 164 to supply the driving torque to the vehicle road wheels 172 and 174 .
[0040] The description of the invention is merely exemplary in nature and variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | A front wheel drive transmission is provided having an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes a sun gear member, a planet carrier member, and a ring gear member. The torque transmitting devices include clutches and brakes arranged within a transmission housing. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of copending International Application No. PCT/EP00/01286, filed Feb. 17, 2000, which designated the United States.
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The present invention relates to a method for operating a telecommunications system containing a plurality of local exchanges in which signaling and traffic data are routed via a network service having routing code recalculation. The method is adapted to provide an integrated services digital network (ISDN) end-to-end supplementary service involving an interaction between two subscribers connected to a local exchange in which knowledge of the subscriber access code used in a called subscriber local exchange is required in the calling subscriber local exchange. The subscriber access code is generated by modification of a called subscriber routing code used by a calling subscriber local exchange. The modification occurs in a transit exchange or a service control point having a translation capability for converting the called subscriber routing code into the subscriber access code. Each local exchange has an application service element for providing the ISDN end-to-end supplementary service.
ISDN end-to-end supplementary services using end-to-end signaling, as defined in ITU-T Recs., e.g. I.253.3, do not work if number translation is required.
A completion of calls to busy subscriber (CCBS) supplementary service is one example of a subscriber service which uses end-to-end signaling, and in which the service is implemented by operations performed in both a calling subscriber local exchange and a called subscriber local exchange. Implementation of a CCBS service requires that the calling subscriber local exchange has knowledge of the called subscriber access code, as used in the called subscriber local exchange.
Completion of calls to a busy subscriber is defined in ITU-T Recommendation I.253.3.
The completion of calls to busy subscribers (CCBSs) supplementary service enables a calling user A, upon encountering a busy destination B, to be notified when the busy destination B becomes free and to have the service provider reinitiate the call to the specified destination B if user A desires. The CCBS supplementary service is applicable to users who are connected to the network via a basic access or a primary rate access. The CCBS supplementary service enables user A, upon encountering a busy destination B, to have the call completed without having to make a new call attempt when destination B becomes free. When user A requests the CCBS supplementary service, the network will monitor for destination B becoming free. When destination B becomes free, then the network will wait a short time as defined in the destination B idle guard timer in order to allow the resources to be reused for originating a call. If the resources are not reused by destination B within this time, then the network will automatically recall user A. When user A accepts the CCBS recall, then the network will automatically generate a CCBS call to destination B.
Global virtual network service (GVNS) is one example of a network service that modifies the routing code (dialed number), with the result that there is no transparency through the network for the called subscriber access code, as used in the called subscriber local exchange.
The global virtual network service is defined in ITU-T Recommendation F.16. The global virtual network service (GVNS) is a multi-network international service that provides private network functions to users at geographically dispersed international locations while minimizing the need for dedicated network resources. It may be offered to customers over the PSTN and/or ISDN. The global virtual network service is a feature-rich communications service. It provides the functions typically associated with the private networks, but utilizing the public switched network(s). The GVNS customer network configuration is defined per customer direction using customer-specific service information resident in multiple networks. The network configurations may be administered by the GVNS customer directly, the GVNS participating service provider(s) and/or the GVNS co-ordinator(s). The GVNS provides the customers with global services as a result of internetworking among the GVNS participating service providers in various countries. GVNS may accommodate this interconnection both via ISDN and non-ISDN facilities.
International Patent Disclosure WO 97/17794 describes a solution to provide CCBS over GVNS for a telecommunications system containing a plurality of local exchanges in which signaling and traffic data are routed between local exchanges via a network service having routing code recalculation. The network service includes a plurality of transit nodes, and a method to provide a supplementary subscriber service involving an interaction between two subscribers. In the method knowledge of a subscriber access code, used in a called subscriber local exchange, is required in a calling subscriber local exchange. The subscriber access code is generated by modification of a called subscriber routing code, used by the calling subscriber local exchange; and the modification occurs in a transit node of the network service.
According to International Patent Disclosure WO 97/17794 the telecommunications system is characterized in that at least some GVNS transit nodes include a relay applications service element (see International Patent Disclosure WO 97/17794, FIG. 3, new completion of calls to busy subscriber application service element (CCBS-ASE)) which is adapted to relay signaling data between local exchanges and which includes translation capabilities for converting a subscriber access code used at a called subscriber local exchange into a called subscriber routing code used by a calling subscriber exchange, and in that signaling data is transmitted between the calling and the called local exchanges via the relay application service element CCBS-ASE in the GVNS transit node.
For the backward direction (local exchange of the called subscriber to local exchange of the calling subscriber) the subscriber access code has to be translated into the called subscriber routing code and signaling data has to be transmitted between the called and the calling local exchanges via the relay application service element CCBS-ASE in the GVNS transit node.
In addition to the requirement of the relay application service element CCBS-ASE in the GVNS transit node the solution requires resources such as transaction IDs (transaction identifiers, see Table 1, positions 24, 25 below). In the GVNS transit node, where two sections of an the end-to-end dialog are connected, all messages being part of the dialog have to pass through the complete protocol stack (up and down) which increases the propagation delay of the messages.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a telecommunications system and a method relating to telecommunications services with number translation which overcome the above-mentioned disadvantages of the prior art devices and methods of this general type.
With the foregoing and other objects in view there is provided, in accordance with the invention, a method for operating a telecommunications system containing a plurality of local exchanges in which signaling and traffic data are routed via a network service having routing code recalculation. The method is adapted to provide an integrated services digital network (ISDN) end-to-end supplementary service involving an interaction between two subscribers each connected to a local exchange in which knowledge of a subscriber access code used in a called subscriber local exchange is required in a calling subscriber local exchange. The subscriber access code is generated by modification of a called subscriber routing code used by the calling subscriber local exchange. The modification occurs in a transit exchange or a service control point each having a translation device for converting the called subscriber routing code into the subscriber access code. Each of the local exchanges is connected to an application service element for providing the ISDN end-to-end supplementary service. The method includes providing the local exchanges supporting the ISDN end-to-end supplementary service with a trigger mechanism for triggering and forwarding a query to the translation device whenever the ISDN end-to-end supplementary service is requested and when the called subscriber routing code is detected. The subscriber access code thus returned from the translation device is forwarded to the application service element, which, based on a received subscriber access code, will establish one and only one end-to-end dialogue with an associated counterpart at the called subscriber local exchange and provide the ISDN end-to-end supplementary service.
The method in accordance with the invention allows a direct, unchained dialogue between the application service element 1 by introducing a trigger mechanism. In a preferred embodiment the trigger mechanism is located in the call control function of the local exchange of the calling subscriber. In a further step the trigger mechanism is equipped with a memory unit, which at least temporarily retains the translated number. The invention also has application to interacting between any network service with routing code (dialed number) recalculation, referred to as number translation and any ISDN end-to-end supplementary service.
With GVNS, as initially defined, there is nothing to prevent a terminating local exchange sending a CCBS possible indicator in the backward release message, since that exchange cannot distinguish between a normal call and a GVNS call. Thus, the CCBS possible indicator is repeated all the way back to the originating exchange. If no solution is found to the problem, all GVNS calls, for which completion of calls to busy subscriber (CCBS) is requested, will lead to unnecessary signaling procedures. The problem created by the interaction between the CCBS and the GVNS will not be solved by simply omitting CCBS for GVNS calls. The CCBS request must either be prevented, or some method for handling it must be provided.
The present invention is based on a telecommunications system containing a plurality of local exchanges in which signaling and traffic data are routed between local (remote) exchanges via a network service having routing code (dialed number) recalculation, referred to as number translation, which network includes a plurality of transit nodes and/or nodes of the intelligent network. The telecommunications system being adapted to provide an ISDN end-to-end supplementary service involving an interaction between two subscribers requires:
knowledge of a subscriber access code, used in a called subscriber local exchange, is required in a calling subscriber local exchange;
the subscriber access code is generated by modification (number translation) of a called subscriber routing code (dialed number), used by the calling subscriber local exchange; and
the modification (number translation) occurs in a transit node or in a service control point of the network service.
According to a first aspect of the present invention the telecommunications system is characterized in:
that a call control function in each local exchange contains a trigger mechanism for providing access to a number translation function to allow for the supplementary service,
that at least some transit nodes or service control points include an application for converting a subscriber routing code (dialed number) used by a calling subscriber local exchange into a called subscriber access code used at a called subscriber local exchange,
that the converted number is sent back to the calling subscriber local exchange, and
that in the calling subscriber local exchange the subscriber routing code (dialed number) is linked to the called subscriber access code.
Preferably the ISDN end-to-end supplementary service is a CCBS service. Preferably the network service having routing code (dialed number) recalculation (number translation) is a GVNS service. Preferably the telecommunications system is a single unitary ISDN system. A CCBS-ASE may be located in each local exchange within the telecommunications system providing CCBS to subscribers connected thereto. Each of the plurality of transit nodes or service control points may be adapted, in use, to receive a request for number translation from a local exchange, providing CCBS to subscribers connected thereto, has an application for number translation located therein. Preferably the application is restricted to the number translation function.
In accordance with an added mode of the invention, there is the step of basing the translation device on a global virtual network service (GVNS) function located in a transit exchange or in a service control point and during the forwarding step the subscriber access code depending from the called subscriber routing code is taken from a database.
In accordance with an additional mode of the invention, there are the steps of locating the trigger mechanism in a call control function of the calling subscriber local exchange; and storing the called subscriber routing code in a memory location of the call control function assigned to the local exchange from which a call was originated is replaced by the subscriber access code and stored in the memory location.
In accordance with a further mode of the invention, there is the step of providing the translation device in the service control point and there is a service switching function contained in the local exchange and during the forwarding step the local exchange acts temporarily as the service switching point.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a telecommunications system and a method relating to telecommunications services with number translation, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a network and protocol architecture for a CCBS;
FIGS. 2 a and 2 b are block diagrams of a network architecture for GVNS, realized as an IN-service (FIG. 2 a ) and realized in a transit exchange supplemented by a GVNS-routing function (FIG. 2 b );
FIG. 3 is a block diagram illustrating a protocol architecture according to the invention, for provision of CCBS over GVNS;
FIG. 4 is a block diagram illustrating the functional entities involved, for provision of CCBS over GVNS; and
FIG. 5 is a flow chart illustrating the adaptation in the call control function part of the existing protocol machine for the access signaling.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is described below with reference to the provision of CCBS over GVNS, but as explained above the invention has application to the interaction between other telecommunications services.
In the specification a number of abbreviations and terms of art are used. Their meanings are briefly explained in Table 1 shown below. In column two of Table 1, reference is made to the document by P. Bocker titled “ISDN Das diensteintegrierende digitale Nachrichtennnetz (ISDN Integrated Services for a Digital Communications Network)” Springer Verlag, Berlin 1990, third edition, hereinafter (P. Bocker) in which the used terms are shown and described in detail (C.: chapter):
TABLE 1
Pos.
P. Bocker
Term
Description
1
FIG.
A-
a calling subscriber
6.14
Subscriber
FIG.
6.19
2
Tab.
A-number
a calling subscriber's E.164 number
4.11
3
FIG.
B-
a called subscriber
6.14
Subscriber
FIG.
6.19
4
Tab.
B-number
a called subscriber's E.164 number.
4.11
5
CCBS
Completion of Calls to Busy Subscriber.
An ITU-T standardization solution is
under development and will be
published as ITU-T Recommendation
Q.733.3. An ETSI solution has been
published as ETS 300 356-18.
6
CCBS-ASE
Application Service Element for CCBS,
is the service handler for CCBS which,
among other things, creates the
signaling contents of the dialogues
between two CCBS-ASES, one on the
A-Subscriber side and one on the
B-Subscriber side.
7
CCNR
Completion of Calls on No Reply
8
DSS1
Digital Subscriber Signaling No. 1; the
signaling protocol used at the access.
9
Tab.
E.164
ITU-T Recommendation E.164
4.11
describes the numbering system scheme
for ordinary telephony. The
B-Subscriber number and the dialed
number are structured, e.g. with
national elements and area code
elements.
10
FIG.
ETSI
The European Telecommunications
1.3
Standards Institute.
11
GVNS
Global virtual network service, as
specified by ITU-T Recommendation
Q.753.6.
12
FIG.
ISDN
Integrated Services Digital Network.
1.2
13
FIG.
ISUP
ISDN User Part, the signaling protocol
6.12
used for inter-exchange signaling. The
signaling protocol is specified in a new
extended edition almost every four
years. These are termed, for example,
“Blue Book ISUP (1988)”, “ISUP92”,
“ISUP-96”. These have been specified
by ITU in Recommendation Q.763.
14
ISUP-96
see ISUP
15
FIG.
LE
Local Exchange
6.13
16
FIG.
MTP
Message Transfer Part; Level 1-3 of SS
6.12
No. 7; ITU-T Recommendations
Q.701-Q.704.
17
Q.763
ITU-T Recommendation Q.763
describing the ISUP signaling protocol
used between Telephone exchanges.
18
Q.931
ITU-T Recommendation Q.931
describing the signaling protocol used in
subscriber access.
19
FIG.
REL
Release message, this is the signal
6.13
message transmitted via ISUP from the
B-Subscriber's exchange when the
physical connection is disconnected, as
occurs in the case of an unsuccessful
connection when the subscriber is busy.
20
Retain
This is a variant of the call completion
option
service which allows for a further call
completion attempt to be performed, at
a later time, if the A-Subscriber is busy
when the A-Subscriber's exchange is
notified, from the B-Subscriber's
exchange, that the B-Subscriber has
become free.
21
FIG.
SCP
Service Control Point; a node of the
6.14
Intelligent Network.
22
FIG.
SSP
Service Switching Point; a node of an
6.14
Intelligent Network.
23
FIG.
SCCP
Signaling Connection Control Part,
6.12
ITU-T Recommendations Q.711-Q.716.
24
FIG.
Transaction
In a TC transaction each separate
6.12
ID
transaction is identified by an identity.
This is called a Transaction Identity.
This facilitates a continuing dialogue
between two user entities, e.g. two
CCBS-ASEs
25
FIG.
TC
Transaction Capability, ITU-T
6.12
Recommendation Q.771-Q.775
26
FIG.
TE
Transit Exchange
6.12
27
TNRN
Terminating Network Routing Number
28
UPT
Universal Personal Telecommunica-
tions. An example of a service which
the B-Subscriber access code is
different from the routing code used at
the A-Subscriber's local exchange LE.
29
VPN
Virtual Private Network
30
PBX
Private Branch Exchange
31
CCF
Call Control Function (see [**], FIG.
6.16)
32
SS7
Signaling System No. 7
33
SCF
Service Control Function (IN) contained
in the SCP
34
SSF
Service Switching Function (IN)
contained in the SSP
35
IEESS
ISDN End-to-End Supplementary
Service (e.g. CCBS)
36
C.
IN
Intelligent Network (see [**], chapter
6.3.6.1
8.4, FIG. 8.4 and FIG. 9.4)
37
INAP
IN Application Part
38
NP
Number Portability
39
SPR
Signaling Point Relay
** Refer to the reference by P. Bocker titled “ISDN Digitale Netze für Sprache-, Text-, Daten, Video-, and Multimediakommunikation (ISDN Digital Net for Speech, Text, Data, Video and Multimedia Communication)” Springer Verlag, Berlin 1997, fourth Edition.
In order to fully understand the present invention, it is necessary to consider the way in which CCBS is provided on the public switched telephone network/ISDN and the way in which GVNS operates. CCBS is an ISDN end-to-end supplementary service in which, when the called subscriber is busy, a new call is established between the called subscriber and the calling subscriber as soon as the terminal of the called subscriber goes from the off-hook condition (busy), to the on-hook (idle) condition. Operation of such a service requires a signaling relation between local exchanges LE, which allows for an “end-to-end” transaction capable based dialogue.
In all the figures of the drawing, sub-features and integral parts that correspond to one another bear the same reference symbol in each case. Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a network and protocol architecture for the provision of CCBS as shown in International Patent Disclosure WO 97/17794. CCBS operates by establishing a dialogue between completion of calls to busy subscriber application service elements (CCBS-ASEs) located in the local exchanges LE of the called and calling parties. Transit exchanges TE which may be, for example, trunk telephone exchanges, are completely transparent to the signaling dialogue established between the two CCBS-ASEs. In other words, the transit exchanges TE do not change the information contained in the signaling data transmitted between the CCBS-ASEs. The signaling system used to establish a call between the two local exchanges LE is in accordance with ISDN user part (ISUP). The signaling system used at the access is e.g. DSS1. For the signaling data transmitted end-to-end a virtual path exists between the two CCBS-ASEs, as shown by the dotted line in FIG. 1 . It should be noted that the signaling connection control part (SCCPs) (see Table 1, pos. 23) in the transit exchanges TE do not effect the signaling data originating from the CCBS-ASEs.
The signaling for the CCBS service is “end-to-end” between the CCBS-ASE containing a CCBS register and the CCBS-ASE containing a CCBS queue. The “end-to-end” signaling is a user of transaction capability (TC) (Table 1, pos. 25), the messages are routed through the network via the SCCPs with normal public E.164 numbers, indicating a subscriber access at the local exchange LE. Interworking with Q.931 accesses, e.g. private branch exchange (PBX), are possible but, in this case, the “end-to-end” information flow will not use TCs all the way. This does not, however, effect the information flow itself, only the medium and coding of the information. CCBS-ASEs do not exist in intermediate exchanges. The CCBS call indicator and the CCBS possible indicator are transmitted via the ISUP.
CCBS request is a direct communication between a CCBS register in the originating CCBS-ASE, normally located in the calling subscriber local exchange LE and the CCBS queue in the destination CCBS-ASE, normally located in the called subscriber local exchange LE. The called party's E.164 number must not be manipulated when signaling data is transmitted between the two CCBS-ASEs, because the signaling is identified by the E.164 number and the CCBS register must know the called party number identifying the called party in the CCBS queue location.
It should be noted that the following CCBS functions, among others, are also handled by the “end-to-end” signaling established between the CCBS register in the calling party's CCBS-ASE and the CCBS queue in the called party's CCBS-ASE:
a) CCBS Cancel;
b) CCBS Suspend;
c) CCBS Resume; and
d) Retain option
None of these functions are dependent on the signaling transparency between the two CCBS-ASEs.
FIG. 2 a shows the network architecture for GVNS. One, or more of the transit exchanges TE may include a GVNS routing function, FIG. 2 b. The GVNS function may alternatively be provided in a service control point SCP, FIG. 2 a. The GVNS routing function operates with database support and modifies the called subscriber routing code (dialed number) to make the call possible.
The CCBS service uses the called party's E.164 number. This number is used in the CCBS register for later CCBS call set-up, and in the CCBS queue for monitoring of the called subscriber and identification of the received CCBS call. If this were not done, the called subscriber in the original call, the CCBS request and the CCBS call cannot be tied to each other. Other signaling information used by the CCBS-ASE has no relevance to routing the CCBS messages through the network and is not affected by GVNS.
The GVNS routing function manipulates the called party number. The GVNS routing function creates, by use of data received from a data base, the terminating network routing number instead of the terminating participating service provider identification. For example, the originating local exchange LE and the destination local exchange LE are not aware of the same called party number.
The basic problem for CCBS is that, for a GVNS call, the functional entities, where the CCBS register and the CCBS queue are located, do not identify the called subscriber with the same E.164 called party number. They are not aware of the number used at the remote (local) location. Since the CCBS service is based on usage of the same number in the CCBS register and the CCBS queue, the service will not work over GVNS without additional procedures in either CCBS, GVNS, or both.
The called party number used at the destination is known only by the terminating local exchange LE and by the GVNS routing function. Since the terminating local exchange LE does not know that the call is a GVNS call, (and, therefore, that special procedures should be applied), the node with the GVNS routing function must send that number back to the originating local exchange LE, (or where appropriate the originating private branch exchange, PBX), when the called user is busy, (or where there is congestion at the interworking point with private networks). The only message sent in this call state is “REL” (Table 1, pos. 19: REL, Release message). A new parameter, or a backward GVNS parameter with the addition of terminating network routing number (TNRN), which amounts to a new parameter, has to be added to the release message REL to carry this number. If the connected number is used, the originating local exchange LE will not know that special CCBS procedures will apply. In any case the connected number is not included in the release message REL.
If the called party number used at the destination local exchange LE can be received by the originating local exchange LE, the number could be used in the CCBS request, instead of the stored called party number, (i.e. the dialed number or the subscriber routing code). The recall would work in these circumstances.
When a CCBS call is set up, the originating local exchange LE may use the stored called party number (i.e. the dialed number) and not the received number (i.e. the number used at the destination and in the CCBS request operation), since the number in the CCBS call set-up should be manipulated, in the same way as for the original call, in the GVNS routing function and the resulting called party number (i.e. subscriber routing code), received by the destination local exchange LE, will be the same as the number stored in the CCBS queue. If the converted number is used for the CCBS call from the originating local exchange LE, no request for number translation will be sent to the GVNS routing function, since the conversion in the GVNS routing function will not work, since it would be the wrong number used as input to the conversion.
The solution to this problem, proposed by the present invention, is illustrated in FIG. 3. A special trigger mechanism is provided in the call control function CCF of the access signaling protocol entity. This mechanism will then initiate a request for a number translation. This will be done using the existing interface to an intelligent network (IN), which can also be used, when the GVNS routing function or a service control function SCF is not provided in the service control point SCP but in a supplement to a transit exchange TE. For the communication between the local exchange LE and the GVNS routing function or the service control function SCF an intelligent network application part (INAP) protocol can therefore be used. Upon receiving the converted number from the GVNS routing function or the service control function SCF the access signaling protocol entity will then inform the CCBS-ASE. From hereon normal CCBS procedures apply. Since the converted number is now available in the CCBS-ASE of the local exchange LE a “direct” end-to-end dialog between the CCBS-ASEs involved can be established and maintained without modification of the ASEs. The use of the trigger mechanism solution results in that no additions need to be made in the signaling protocols for GVNS and CCBS. The CCBS supplementary service realized in the local exchange LE is not affected at all. Thus, the interworking problem can be resolved, in accordance with the present invention, entirely within the access signaling protocol entity, without affecting the existing CCBS implementations.
Until completion of a requested service (e.g. CCBS) the converted number will preferably be kept available by the call control function CCF. In case of a calling subscriber connected to the local exchange LE a further number translation during the CCBS call could be avoided: as soon as the called subscriber has terminated his call (and is therefore no longer busy) the calling procedure can be resumed (execution of the CCBS call: the local exchange LE of the calling subscriber processes the circuit related call) while using the converted number which has been kept available in a memory of the call control function CCF. In case of a calling subscriber connected to the private branch exchange PBX the CCBS call may enter the public switched telephone network (PSTN)/ISDN via a local exchange LE different from the one that was involved in the CCBS dialog: since the converted number is not available in the call control function CCF of the local exchange LE the normal procedure for circuit related call establishment applies.
FIG. 4 illustrates the functional entities involved, for provision of CCBS over GVNS. Process communication is taking place between the call control function CCF and the service switching function SSF contained in the local exchange LE of the calling subscriber, acting temporary as a service switching point SSP on the one hand and between the call control function CCF and the application service element (e.g. for CCBS) on the other hand. The application service element for CCBS, is the service handler for CCBS which, among other things, creates the signaling contents of the dialogue between two CCBS-ASEs, one in the local exchange LE of the A-subscriber and one in the local exchange LE of the B-subscriber. The call control function CCF contains a memory M in which the translated number is stored for future use.
FIG. 5 shows the changes in the protocol entity of the access signaling (described as a finite state machine).
Upon a CCBS request (CCBS req—step 10 ) from a subscriber, whose call reached a busy subscriber, the called number is analyzed in step 20 (nr-check).
In a next step 30 (tr-req) it is decided whether a number translation is required (e.g.: the called number is XX XX which must be converted to 031-322 XX XX).
In the case where the number translation is not required a CCBS-ASE is invoked, step 40 , and the (called) number that is the actual number of the called subscriber, is forwarded to the CCBS-ASE, step 50 .
In case where the number translation is required a query, step 60 , is sent to the GVNS routing function, step 70 .
After a waiting period, step 80 , a new number is provided, step 90 . Upon receipt of the new number it is stored in the memory M, step 100 , the dialed number is replaced with the new number, step 110 , and a CCBS-ASE is requested, step 120 , and the converted number is forwarded to the CCBS-ASE, step 130 .
The inventive concept resides in introducing a mechanism that allows the reuse of existing equipment to query a database and a memory location for the converted number. The invention has application in all connection set-ups in which the following service combinations exist:
a) completion of calls—GVNS;
b) completion of calls—virtual private network (VPN);
c) completion of calls—free number group;
d) completion of calls—personal number service; and
e) completion of calls—intelligent network services having number recalculation in SCP
The invention is not limited to completion of calls, but can be used for any ISDN end-to-end supplementary service using service logic distributed between two local exchanges LE, communicating with transaction capability based dialogs in those cases where the services interact with other services performing B-number recalculation (number translation). | A telecommunications system containing a plurality of local and transit exchanges in which signaling and traffic data are routed between remote exchanges via a network service having routing code recalculation is described. The system is adapted to provide an ISDN end-to-end supplementary service between two subscribers in which a subscriber access code is generated by modification of a called subscriber routing code, used by the calling subscriber local exchange. The local exchanges that have an applications service element for providing the ISDN supplementary service, include a mechanism to trigger a query, which is sent to a translation device whenever the supplementary service is requested and a subscriber routing code is detected. The subscriber access code returned from the translation device is forwarded to the applications service element, which, will establish an end-to-end dialogue with it's counterpart at the called subscriber local exchange and provide the ISDN supplementary service. | 7 |
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